NAT'L INST. OF STAND & TECH R.I.C.

A 11 ID 3 4 3 0 4 5 A

NBSIR 81 -2447 W

Reference

NIST

PUBLICATIONS

447 W

1981 Annual Report

Office of Standard Reference

Materials

U S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Measurement Laboratory

Washington, DC 20234

October 1 981

Final

Issued December 1981

QC

100

U56

81-2447

Prepared for U S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Washington, DC 20234

NBSIR 81-2447

1981 ANNUAL REPORT

OFFICE OF STANDARD REFERENCE

MATERIALS

G. A. Uriano and S. D. Rasberry, Editors

U S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Measurement Laboratory

Washington, DC 20234

October 1 981

Final

Issued December 1981

Prepared for U S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Washington, DC 20234

U S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director

TABLE OF CONTENTS

Page

1. INTRODUCTION

1.1 Program Description 1 1.2 Demand for SRM's and External Trends Affecting

the Program 4

.1 Increased Importance of Measurement

Compatibility in a Technological World 4

.2 Increased Cost of Raw/Processed Materials

and Energy 5 .3 Increased Development of New Materials

in High Performance Applications 5

.4 Increased Development and Implementation of

Government Imposed Health and Safety 6

1.3 Current and Future Need for SRM's 6

.1 Industrial Quality Control 6

.2 Health 7 .3 Environment 7 .4 Science and Metrology 8

2. TECHNICAL ACTIVITIES

2.1 Introduction 10

2.2 Summary of New and Renewal SRM's 10

2.3 FY81 SRM Sales Report 10

2.4 Highlights of Research Projects 10

.1 Succi nonitrile Triple Point Standard 13

.2 Rubidium Melting Point Reference 14

.3 Investigation of Techniques for the Activity

Calibration of 14

C and "Tc 15

.4 Measurement of Absolute Sputtering Yields 17

.5 Variation with Time of the Heat of Combustion

of Coal 18

.6 Modernization of Color Fading Standards 20

.7 Sulfur in Metals by IDMS 23

.8 D.C. Plasma Spectrometry 25

.9 Quantitative Recovery of Iodine from

Biological Matrices 26

l
JO Development of a Radiochemical Separation

Procedure for Tin in Biological SRM's 27

J1 Development of ID/MS for Trace Concentrations

of Vanadium 28

.12 Metal -on-Quartz Filters. ...... 30

.13 Light Elements in Complex Matrices . 30

.14 Two-Dimensional Proton NMR Spectroscopy of

Hydroxyl Proton Coupled a- and 8-D-Glucopyranose 32

.15 Comparison of Two Isotope Dilution Definitive

Methods for the Determination of Glucose in

Serum and Evaluation of the AACC Reference

Method for Glucose 37

.16 Comparison of Two (ID/MS) Methods for

Determination of Total Serum Cholesterol .... 38

.17 Methods Development for the Analysis of

Organic Nutrients in Food. ..... 40

.18 Surface Reactions Related to Instability

of Compressed Gas Mixtures 45

.19 Thin Film Calibration Standards for

Microanalysis 46

.20 Stability Testing of SRM's 48

.21 Eddy Current Standards 49

.22 Abrasive Wear Standard 50

.23 Particle Shape Characterization. 51

.24 Pitting and Crevice Corrosion Standards 52

.25 Crystallite Microsize 52

.26 Glass SRM Research ..... ..... 53

.27 Computer SRM Research 54

.28 Thermal Insulation SRM Research 54

2.5 SRM Production 56

.1 Benchmark Low Alloy Steels —SRM 1 261 a- 1 265a . . . 56

.2 Line Pipe Steel —SRM 1269. . 56

.3 2 1/4 Cr— 1 Mo Low Alloy Steel--SRM 1270 .... 56

.4 Cast Steel—SRM C1173 56

.5 High Alloy Steels-SRM's C1287-C1289 57

.6 Hafnium Certified in Zirconium-4—

SRM's 1234-1239. ........ 57

.7 15% Austenite in Ferrite--SRM 486. 58

.8 Dye Penetrant Test Block--SRM 1850 ....... 58

.9 Obsidian Rock and Basalt Rock--SRM's 278

and 688 •

i i

58
.10 Soda-1 ime-sil ica Glass for Gradient-furnace

Liquidus Temperature— SRM 773 59

.11 Optical Microscope Linewidth Measurement

Standard--SRM 475 59

.12 Silicon Resistivity Standard for Eddy Current

Testers--SRM 1523 60

.13 Polystyrene (narrow molecular weight

distribution)— SRM 1479 60

.14 Butyl Rubber--SRM 1459 60

.15 Potassium Chloride for Solution

Calorimetry--SRM 1655 60

.16 Benzoic Acid, Acidimetric Standard--SRM 350a ... 61

.17 TRIS, Basimetric Standard—SRM 723a 61

.18 Human Serum--SRM 909 61

.19 4-Nitrophenol--SRM 938 61

.20 Sodium Pyruvate—SRM 910 62

.21 Oxygen in Nitrogen, 21 Mole Percent—SRM 2659. . . 62

.22 Sulfur Dioxide in Nitrogen for Stack Analysis. . . 62

.23 Methane and Propane in Air--SRM 1660a 63

.24 Generator Columns for Polynuclear Aromatic

Hydrocarbons—SRM 1644 63

.25 Stabilized Wine--SRM 1590 64

.26 Reflection Step Tablet--SRM 2061 64

.27 Computer Amplitude Reference, Disk

Cartridge—SRM 3210 64

.28 Second Surface Aluminum Mirrors for Specular

Reflectance—SRM' s 2023-2024 65

.29 Plutonium-244 Spike Assay and Isotopic Standard—

SRM 996 65

.30 Environmental Radioactivity, "Rocky Flats Soil

Number 1"—SRM 4353 65

.31 Hydrogen-3 Radioactivity Standard— SRM 4361. ... 66

.32 Low-energy Photon Standard—SRM 4266 66

.33 Mixed-Radionuclide Point-Source Standard 66

Efficiency Calibration of Germanium-Spectrometer

Systems— SRM 4276 66

2.6 Data Base Management System 67

2.7 ASTM Research Associate Programs 67

.1 Metal SRM' s 67

.2 Glass SRM's 67

.3 SRM's for Particle Metrology 68

2.8 AIF Research Associate Program 68

2.9 International SRM Activities 68

.1 International Organization for Standardization . . 68

.2 International Union of Pure and Applied Chemistry. 69

.3 U.S. -Egypt Cooperative Program 69

.4 Royal Society of Chemistry Meeting 69
.5 DoC Trade Exhibits in Ecuador and Columbia. .... 70

.6 Chemical Institute of Canada Meeting. ....... 70

.7 Fourth European Conference on Analytical

Chemistry 70

.8 International Conference on Heavy Metals in

the Environment . 70

.9 U.S. -Italian Cooperative Research on Reference

Materials 70

.10 NBS-WH0 Collaboration 71

.11 Bilateral Activities 71

3. 0SRM STAFF PUBLICATIONS, INFORMATION TRANSFER AND COMMITTEE

ACTIVITIES

3.1 Publications, Journal Articles, and Written Reports

by OSRM Staff in FY81 72

3.2 Technical Lectures/Talks Given by OSRM Personnel ..... 74

3.3 Standards Committee and Other Standards Activities .... 76

3.4 NBS Special Publication 260 Series 77

3.5 FY81 Technical Exhibits with Staffed SRM Displays 78

iv
1. INTRODUCTION

This report summarizes the major operational and technical activities of the Office of Standard Reference Materials (OSRM), National

Bureau of Standards (NBS) for the fiscal year ending September 30, 1981

(FY81). The major technical and operational highlights which occurred

during FY81 are described as well as OSRM personnel and budget resources,

budget initiatives and a number of planning and budgetary issues facing

the SRM program.

1 .1 Program Description

Standard Reference Materials (SRM's) have been produced, certified,

and issued by NBS since 1906. These materials, with specific chemical

or physical properties certified by NBS, have found wide acceptance

especially by industrial users needing to maintain or increase high

levels of productivity. Today, 84 of the 100 largest manufacturers in

the U.S. buy and use SRM's. Together with 10,000 other users, they buy over 40,000 SRM units per year at a total price of about $3,500,000.

The SRM's have a vital role in promoting industrial productivity by

helping companies maintain:

-- Reliability and uniformity of materials in meeting

specifications.

-- Quality control in raw materials and produced goods

or services.

-- Interchangeability of materials and subcomponents.

In addition to the industrial customers, major SRM users also

include federal and state governments, universities, and nonprofit

research establishments, particularly for SRM's used in the areas of

health, environmental protection, metrology, and forensic science.

Approximately 1,000 different SRM's are currently available with a total

inventory market value of over $18 million. Table 1.1 summarizes the

types produced.

1
Tab! e 1 .

1

SRM Types Produced at MBS

Steel

s

Isotopics

Steelmaking alloys Ion activity

Cast irons Mechanical and metrology

Cast steels Superconductive thermometric

Nonferrous alloys Freezing points

Gases in metals Melting points

High purity metals Calorimetric

Electron probe mi croanalytical Vapor pressure

Standard chemicals Thermal conductivity

Cl inicals Thermal expansion

Biologi cal

s

Thermal resistance

Botanical s Thermocouple materials

Environmental

s

Magnetic

Industrial hygiene Optical

Metallo-organic compounds Gas transmission

Ferti 1 izers Permittivity

Ores Reference fuels

Mi neral

s

Resistivity

Refractories Rubber materials

Carbides Computer tapes

Glasses Sizing standards

Cements Color

Trace elements Photographic

Nuclear materials Surface flammability

Radioactivity Smoke density

X-ray diffraction Water vapor permeance

2
The first four standard samples issued by NBS in 1906 helped cast

iron manufacturers improve productivity by increasing their control over

the manufacturing process. Well characterized, certified NBS standard

samples of cast iron chips served as a check on the composition of the

cast iron being produced. One of those original samples has been reissued

thirteen additional times and is still in use today. This fact illustrates

NBS'S commitment to provide continuity of service. As long as a strong

need exists for an SRM and it is not available from another source, the

Bureau strives to continue to provide it.

By 1911, at the request of such organizations as the American Steel

Manufacturers Association and the American Chemical Society, NBS had

available about 25 different reference materials. These materials

included SRM's for determining the composition of steels, brasses, ores,

and sugars and a combustion SRM for calorimetry. Materials research

conducted by the Bureau has always been the central resource for the

Standard Reference Materials effort. SRM's are characterized and certified

largely on the basis of analytical methods developed in the course of

that research. For many years, the NBS analytical chemistry program

served almost exclusively as the basis for SRM development. Today,

however, virtually all major NBS technical areas participate directly,

from radiation research to computer science.

Between the two World Wars, SRM activities grew slowly but steadily.

Industrial needs for materials for chemical analysis were the major--

almost exclusive-impetus. Starting in World War II, the needs for

SRM's began to grow and change. As a primary national laboratory for

materials research, NBS contributed to the Manhattan Project through

pioneering work in the separation of uranium isotopes and developing

SRM's for isotopic composition of materials containing uranium and

plutonium.

After the war, breakthroughs in the fields of nuclear physics,

electronics, and polymer research brought new demands for Standard

Reference Materials. By 1951, there were samples for spectrographic as well as chemical analysis of raw and processed materials (primarily

metals, ores, chemicals, and ceramics) and special hydrocarbon blends

for calorimetry. SRM's had been developed for evaluation of color and

fading characteristics of materials. Samples were being certified for

important physical properties such as pH, melting point and radioactivity.

In the early 1 960 ' s , NBS realized that SRM's were becoming increasingly

important to industry and that industrial demand would continue to grow.

The Bureau also recognized the potential contribution SRM's would have

in solving measurement problems in emerging areas of national need such

as clinical and environmental analysis. Consequently, in 1964, the

Office of Standard Reference Materials (OSRM) was established and given

the responsibility of directing all SRM activities. Previously, the

individual technical divisions had managed the SRM program through the

3
Analytical Chemistry Division. With the establishment of a new office,

a number of new thrusts were developed. New program areas were identified

and initiated, including the start of what was to become a major effort

in developing SRM's for clinical chemistry.

1 . 2 Demand for SRM's and External Trends Affecting the Program

The last fourteen years has seen the NBS-SRM Program greatly expand

the nature and scope of its activities. In 1966, NBS offered 559 different

SRM's for sale, which were intended to serve the measurement needs of

rather limited but important segments of the U.S. economy. At that time,

the majority of SRM's consisted of compositional standards (primarily certi

fied for bulk constituents or purtiy) designed for use in quality control

systems during mining and manufacturing of raw and processed industrial

materials. The SRM inventory primarily consisted of metal bearing ores,

metals and alloys, cement, glass, and inorganic chemicals.

In 1969, SRM development and production activities were involved in

only six NBS technical divisions with over 90 percent of the production

occurring in what was then the Analytical Chemistry Division. At that time

NBS management recognized that SRM's could serve as an important mechanism

for transferring the output of a broad spectrum of NBS measurement programs

including physical and engineering measurements as well as chemical measure

ments to the user community.

By 1981, the SRM Program was considerably strengthened through the

participation of 23 technical divisions and eight program offices within

NBS. This enabled NBS to increase the number of SRM's by over 500 (i.e.,

by nearly 100 percent in the last 14 years). Included were SRM's in many

new areas such as computer technology, fire safety, forensic science, and

radiopharmaceuticals, with particular recent emphasis on the two important areas of environmental and clinical measurements. The expansion of the

SRM Program was accompanied by a corresponding expansion of the customer

base as indicated by SRM sales. In the period 1969-1981, SRM sales more

than doubled to $3.5 million for FY81 , of which approximately $1,400,000

is recovered production capital. The number of units sold each year

also increased steadily over this period. In 1971, NBS sold 29,600 units

of SRM's; and in 1981, approximately 40,000 units were sold.

The considerable expansion in the scale and scope of the NBS-SRM

Program as well as the increased participation of many different technical areas within NBS, has been in response to a number of trends, which have

been and are continuing to occur in the world. The trends are summarized

below:

. 1 Increased Importance of Measurement Compatibility in a Technological

World

The importance of compatible and accurate measurement systems to

international and domestic commerce, to the development and enforcement

of health and safety regulations, and to science and technology continue

to grow.

4
As evidence of the importance of reference materials to assuring

measurement compatibility on a worldwide basis, a number of important

international standards organizations have initiated reference materials

activities in recent years, including the International Standards

Organization (ISO), the Organization for Legal Metrology (OIML), the

International Union of Pure and Applied Chemistry (IUPAC), and the World

Health Organization (WHO). In addition, programs aimed at the development

and certification of Standard Reference Materials have been initiated

(or expanded) in a number of countries including France, Brazil, Korea,

Poland, USSR, and Japan. The nine countries of the European Economic

Community (EEC) have initiated a multi-nation reference material program

under EEC sponsorship. More recently, the People's Republic of China

(PRC) has established an Institute for Reference Materials, which is

associated with the Chinese National Institute of Metrology. The PRC sent

three scientists to NBS for training on reference materials related

projects during FY81

.

During the next decade, international SRM activities are expected

to increase dramatically, including the joint development of multi-national

certified reference materials and increased requirements for the use of

reference materials to meet international standards.

•2 Increased Cost of Raw/Processed Materials and Energy

Recent increases in the cost of raw and processed materials, as well as the cost of energy, have resulted in the development of more

stringent procurement specifications for materials sold in national

and international commerce. Standard Reference Materials are being increasingly used to provide a basis for the arbitration of disputes

between producers and users of materials, as well as for traditional

uses as part of production quality control systems.

•3 Increased Development of New Materials in High Performance

Appl i cations

The development and use of materials for high-performance applications

has increased considerably in recent years. This trend is leading to the

development of a wide variety of new high-performance materials serving

many diverse uses. Examples range from high-temperature corrosion-resistant

alloys used in aircraft turbine blades to plastic foams used in building

construction. Many of these high-performance materials are used in critical

applications where their failure in service could result in serious safety

hazards. This has led to the development of rigidly enforced trade specifications and to the need for reliable production quality control, which in

turn has resulted in increased demand for SRM's.

5
•4 increased Development and Implementation of Government Imposed

Health and Safety Regulation

The trend to greater federal, state and local government regulation

of the environment, health care system, and transportation systems is

also resulting in intense demand for new SRM's. Effective development

and enforcement of regulations depends on the availability of accurate,

reliable, and compatible measurement systems. The NBS response to

this trend has been the establishment of a number of programs aimed

in part at providing a reliable measurement base for regulatory agencies.

These have included the Environmental Measurements Program, Nondestructive

Evaluation Program, Resource Recovery Program, Recycled Oil Program, and

the Nuclear Safeguards Program. All of these programs have required the

development of new SRM's to serve as measurement technology transfer

mechanisms. An increasing number of government regulations in the environmental, health, and nuclear areas are expected to mandate the use of

NBS-SRM's directly or the use of commercial reference materials traceable

to NBS-SRM's.

1.3 Current and Future Need for SRM's

The use of NBS-SRM's by the Nation's primary metals industry illustrates

their importance to the United States economy. For example, NBS steel SftM's are relied upon to verify that the analytical instruments used to measure

the constituents in steels are, in fact, measuring correctly and within

the allowed limits of error. The quality of the steel is dependent on the

quantities of the specific constituents; too little of these critical con- stituents results in poor quality steel, while too much results in waste

of money and natural resources usually with no improvement in the quality

of the steel. For instance, the presence of vanadium in iron produces a tough steel. Similarly, specific amounts of chromium and nickel make the

steel stainless (corrosion resistant). Steel chemists must analyze each

batch of steel for constituents and adjust the mixture when necessary.

They periodically verify the measurements made by their equipment through

the use of certified NBS-SRM's, which correspond to the particular alloy

being produced.

In addition to the example cited above, many new demands for SRM's

have occurred in nonindustrial areas, particularly with respect to

improving the accuracy and reliability of clinical and environmental

measurements. These demands include the following:

. 1 Industrial Quality Control

Over 800 SRM's are currently used directly for establishing and

maintaining measurement quality control in a variety of industries

including metals, glass, ores, rubber, plastics, primary chemicals,

energy generation, measurement instrumentai ton, and computers.

Industrial SRM's are also used in a number of important engineering

applications. For example, SRM's are used to (a) standardize materials;

(b) standardize computer components such as magnetic tapes (GSA

purchase specifications are based in part on these SRM's); and

6
(c) evaluate the quality of electronic components such as integrated

circuits. OSRM projects that 220 new SRM's will be needed to serve

industrial customers by FY86 (Table!. II). These include 80 new metal

compositional SRM's (primarily high-performance alloys), 30 nonmetal

SRM's (including both physical and compositional properties or ores,

glass, and inorganic chemicals), 24 new chemical SRM's (including a series of new synthetic rubber standards), and 46 new engineering

standards; e.g., for evaluation of dimensions of integrated circuits.

Also needed are 40 isotopic, assay, radioactivity, and physical property

SRM's for nuclear applications. During this time period, NBS is also

expected to discontinue 246 industrial SRM's contained in the existing

inventory, including 108 metal compositional SRM's and 58 engineering

SRM's. Thus, the total number of industrial SRM's in inventory is

expected to decrease slightly over the next five years, although the

spectrum of SRM users will continue to broaden.

.2 Health

Over 40 SRM's are now being used to improve the accuracy

of over four billion measurements made annually in hospital laboratories

at an estimated cost of more than $8 billion. NBS SRM's and reference

methods help provide the basis for; (1) the regulation of in vitro diagnostic

products by the Food and Drug Administration (FDA); (2) the proficiency

testing of 7,500 clinical laboratories by the College of American Pathologists

(CAP); (3) the proficiency testing of 1,000 laboratories in the Medicare

network by the Center for Disease Control (CDC); and (4) has begun to provide a critical component of the new National Reference System for Clinical

Chemistry (NRSCC), recently established by the National Committee on Clinical Laboratory Standards.

The 1976 OSRM clinical impact assessment study, recent long-range

planning studies, and other information indicate that 25 new clinical

SRM's will be needed before 1986 (Tablel.II). The most important needs

are for human serum matrix standards characterized for clinically important

constituents and also SRM's for enzyme and enzyme reagent materials,

individual proteins, peptides, hormones, and vitamins.

.3 Environment

Over 80 SRM's are now being used to assure measurement

compatibility in both air and water pollution analyses. A series of 64

gas SRM's provide the accuracy basis for motor vehicle pollution monitoring

and mileage testing, as well as for stationary sources and ambient air

monitoring. Use of many of the gas SRM's is mandated by EPA regulations.

A limited number of trace element standards is also available for use in

water pollution analysis and monitoring of industrial atmospheres.

The Environmental SRM category has been the fastest growing category

during the past five years. However, the rapid growth of environmental

SRM's is expected to slow considerably in the next five years as a result

of expected reductions in resources to support projects in this area. OSRM

estimates that 25 new gas SRM's and 30 new water pollution SRM's will be

needed by FY86. Major emphasis must be placed on the development of SRM's

7
for trace analysis of organics in air and water (e.g., PNA's, PCB's, and

pesticide residues), for quantitative analysis of toxic chemical species

(as opposed to elemental analysis). Also needed are SRM's for chemical

and physical characterization of particulates (including asbestos-like

materials), although it is unlikely that any such SRM's will reach production stage in this five-year period.

.4 Science and Metrology

Currently, over 100 SRM's help to maintain basic measurement

quantities such as temperature. For example, SRM's are used in the

establishment of fixed reference points for the International Practical

Temperature Scale (IPTS), the scale to which all temperature measurements

ultimately must be referred. Recently, SRM's have contributed to improving

the compatibility of thermal conductivity with a worldwide network of

laboratories working through the North Atlantic Treaty Organization and

in cooperation with CODATA.

OSRM projects that 10 new metrology SRM's will be needed by 1986,

including a series of new temperature SRM's (to extend the temperature

range of the IPTS scale), and a number of electrical reference standards.

Summary

Based on well -characterized needs identified through SRM proposals,

various surveys and discussion with key NBS, other agency, and private

sector technical managers, OSRM projects that NBS will have to maintain

an inventory of over 1,000 SRM's during the period FY82-86 to meet customer

demands in an orderly fashion. Table 1 . I I summarizes the projected SRM

production necessary to meet anticipated customer needs in each category.

Over $18 million in production capital will be needed in the FY82-86 period

to produce an expected 537 renewals and 310 needed new SRM's. OSRM also

projects that 316 existing SRM's will be discontinued during this period.

8
OSRM

Projection

of

Demand

for

SRM

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<d fd E E n— •r— •r- •f— •rO r— d) ra o +-> c a) a -o OS > > OO ra •r— +->

CL) o sz ZJ (T3 sz c £= d)

u o 2: ZL c_> zc QC LlJ UJ LU zc 00 1— As

of

July

31,

1981.

Includes a

number

of

multiple

renewals

in

the

Radioactivity,

Engineering,

Environmental

Gases,

and

Health

category.
2. TECHNICAL ACTIVITIES

2.1

Introduction

Section Two is a summary of the technical and related activities

required to research, develop, produce, inventory and sell Standard

Reference Materials. Parts 2.4 and 2.5 provide highlights of specific

technical projects for FY81.

2.2 Summary of New and Renewal SRM's

Table 2.1 summarizes the number of new and renewal SRM's produced

in FY81 as distributed over major program categories. Fifty-nine new

and 139 renewal SRM's were completed with the largest number being in

the metals, radioactivity and environmental categories.

2.3 FY81 SRM Sales Report

Table 2. II summarizes SRM sales in terms of units, production

income and total income for the year ending September 30, 1981. The

$3,472,900 in total and $1,432,000 in production income were both records

for the SRM program and represent one-year increases of 16 percent and

25 percent respectively. The 40,304 units sold is a decrease of one percent relative to last year.

During FY81 , over 10,000 orders and 4,000 technical inquiries were

processed. A comprehensive evaluation of all SRM's in inventory resulted

in $177,176 worth of material being obsoleted, which is less than three

percent of the value of the inventory plus work-in-process. At the end

of FY81 approximately 250,000 sales units of SRM's were carried in

inventory with an asset value of $6,113,000 (including other agency

costs) and a market value of about $18,000,000.

2.4 Highlights of Research Projects

This section describes SRM research highlights during FY81 . Forty

SRM research projects were active during the year in seventeen different

NBS divisions. Rather than provide a complete review, some major highlights are described.

10
Table 2.1

SRM's Produced in FY 1981

Category New Renewal

s

Total

INDUSTRIAL

Metal

s

17 21 38

Nonmetals 1 3 4

Chemicals/Rubber/Plastic 3 4 7

Engineering 1 30 31

Radioactivity 4 27 31

Subtotal 26 85 111

ENVIRONMENTAL

Gases 4 24 28

Liquids/Solids 2 7 9

Subtotal 6 31 37

HEALTH 4 4 8

SCIENCE/METROLOGY 23 19 42

TOTALS 59 139 198

11
Table 2. II FY 1981 SRM Sales by Category

Units

$

Production

Income(NBS)

$

Total

Income*

INDUSTRIAL

Metal

s

14,394 $290,722 $979,490

Nonmetal

s

3,889 37,433 211 ,192

Chemical s/Rubber/Plastic 5,838 95,856 360,402

Engineering 5,749 207,603 412,056

Radi oacti vi ty/Nucl ear 2,024 175,539 305,661

Subtotal

s

31 ,894 807,153 2,268,801

ENVIRONMENTAL 3,537 305,155 586,688

HEALTH 3,100 128,947 294,649

SCIENCE/METROLOGY 1,470 188,077 298,949

GM/RM 303 2,996 23,858

TOTALS 40,304 1 ,432,328 3,472,945

*Includes income collected for other agencies and other factors.

12
.1 Succi noni tril e Triple Point Standard

B. W. Mangum

Temperature and Pressure Measurements

and Standards Division

Center for Absolute Physical Quantities

During FY81 , one relatively large glass cell of succinonitrile (SCN) was obtained and some preliminary measurements were made of its melting

behavior. The cell contained approximately 300 g of SCN. The melting

behavior was observed by means of a standard platinum resistance thermometer (SPRT), used in conjunction with a Cutkosky ac resistance-ratio bridge.

Based on the preliminary testing of this one sample in this cell, two new cell designs have been made and samples in these new cell designs have

been ordered. One of the new cells is to be similar in shape to a triplepoint of water cell and is to contain approximately 750 g of succinonitrile. That sample, when delivered toward the end of 1981, will be very

carefully investigated with an SPRT as to its melting/freezing behavior, the

value of the triple-point temperature on the IPTS-68, and the reproducibility

of the triple-point temperature, both with time and as a function of mantle

preparation.

The second design will incorporate approximately 50 g of succinonitrile

in a glass cell similar to and only slightly larger than SRM 1968 - the

gallium melting-point standard. The thermometer-well of this cell is to

be approximately 0.150 inch in diameter, so that it will accept thermistor

thermometers, thermocouples and small industrial -type platinum resistance

thermometers. It is anticipated that this relatively small sample will be

a very useful temperature fixed point for the clinical laboratory, as well

as for industrial and general laboratory use.

From the preliminary results of our investigation, it appears that

the triple-point temperature of succinonitrile is stable, has a value near

58 °C, and is fairly easy to realize. The melting plateau appears to be

fairly flat, perhaps a few mK melting range at most. This implies that the

material can be highly purified by the zone-refining method used in the

preparation of our sample. Since succinonitrile is an organic compound,

it has two minor disadvantages, a low thermal conductivity and a small heat

of fusion. These disadvantages, however, are not serious ones and certainly

do not preclude in any way the use of this material as a temperature fixed

point.

13
.2 Rubidium Melting Point Reference

B. W. Mangum

Temperature and Pressure Measurements

and Standards Division

Center for Absolute Physical Quantities

During FY81 , we did extensive testing of rubidium in steel cells.

Prior to the testing, however, we encountered several difficulties. A

1- kg sample, supposedly of highest purity, was shipped to us in what we later found out to be an industrial grade container, which caused con- tamination of the rubidium. This then required the procurement of

another sample, of the highest purity material commercially available,

from a different supplier. We had previously constructed an all-stainless

steel handling and transfer system so that we could attempt additional

purification of the rubidium by vacuum distillation. It was extremely

difficult to monitor that system in such a way as to know just where the

rubidium was in the system and how much was at any given place. An even bigger problem occurred after the transfer of the rubidium into steel

cells - that was the clean-up process. The distillation and transfer

system contained small quantities of rubidium throughout and because of

its extreme reactivity, the rubidium was difficult to remove in a controlled

manner. Consequently, we contracted with a producer to transfer under

vacuum, a 1 _ kg sample of pure rubidium into seven stainless steel cells

which we had constructed, cleaned, dried, and then evacuated under high vacuum at elevated temperatures.

The samples of rubidium, in the stainless steel cells, obtained from

the contractor, were investigated with regard to their melting/freezing

behavior, their melting-point temperatures, their freezing-point temperatures, and the reproducibility of the mel ting-/freezing-point temperatures.

The melting behavior and the melting-point temperature of a given

cell was reproducible to within about ±0.01 °C. The maximum temperature

attained after recalescence began during freezing experiments on any given

cell was reproducible to <_ ±0.01 °C. The freezing point or, more specifically, the maximum in the freezing curve may be somewhat easier to

realize in the general laboratory situation than the melting point. The

melting point, on the other hand, enables one to perform numerous calibrations using the same melting experiment. The melting-point temperature,

as used here, refers to the value of the "plateau" of the melting curve. Thus, both melting-point and freezing-point determinations are practical.

Although the melting-point and the freezing-point temperatures for a given cell were reproducible to about ±0.01 °C, the spread among the cells

was greater. The variation of the melting-point or the freezing-point

temperature from cell to cell is thought to be due to different levels of

impurities in the different cells. Since the samples were all taken from

the same lot of rubidium, there must have been different amounts of con- taminants in the different cells. This means that the SRM's cannot be

14
assigned one melting-point and/or freezing-point temperature for all cells,

but that any given SRM will have a melting-point and/or freezing-point

temperature which may or may not be the same as that for another SRM.

The SRM's will begin to be tested and stockpiled next year.

The triple-point temperature was determined to be 39.272 °C for pure

rubidium.

.3 Investigation o^ Techniques for the Activity

Calibration of i4 C and "Tc

B. M. Coursey and A. T. Hirshfeld

Nuclear Radiation Division

Center for Radiation Research

Two projects in the Radioactivity Group involved the measurement of

long-lived radionuclides emitting only beta particles. The nature of beta

spectra, with a finite number of particles with energies too low for

detection, makes an accurate a priori estimate of the efficiency of most

counting systems difficult.

In the case of 14

C, important for dating ancient objects, this

efficiency had been maximized in past measurements by transforming the

material into gaseous

14 C0 2 and mixing it with the counting gas used in

a group of well-characterized proportional counters. (See Method A, in

table 2. Ill), however, a calibration performed in 1973 was disturbingly

discrepant (about 1.4 percent) with a value obtained in 1958. Moreover,

there were even larger discrepancies among the standardizing laboratories

of nations with which we had compared values.

It was first considered that a direct counting of a gaseous

14 C

compound which could also be dissolved directly in a liquid scintillator

for comparison with past measurements should be attempted. This would

eliminate any uncertainty in the transformation to a gas. However,

available funds were not sufficient for this purpose, and two alternative

approaches, both using liquid scintillators, were used. These same methods were also applied to the measurement of "Tc, a significant component of

nuclear waste from power plants and a residue of the most commonly used

radiopharmaceutical. Its very long half life (2xl0 5 y) made the preparation of thin solid sources impossible.

The first technique uses theoretical calculations of beta spectra and

liquid-scintillator response to deduce the 14C and "Tc counting efficiencies

from those determined with other (already calibrated) radionuclides. The

results obtained using this technique are shown in method C of the table.

Data are being taken with the other, more complex, method (see Method D of the table). In this procedure, a known quantity of a radionuclide which

15
Table 2. Ill

Status Report of Intercompari son of Various Counting Methods

for 14 C and "Tc

CARBON - 14 TECHNETIUM - 99

HALF

BETA

A.

LIFE (Years) 5730 213,000

k- RAY ENERGY

(MAX) (keV) 156.48 293.50

(AVE) (keV 49.35 84.60

GAS COUNTING 4tt3( GC)

1958 (NBS) 1.932 x 105 Bq g ’l

+ 2.0% Method not

1973 (NBS) 1.906 x 10 5 Bq 9

"i

1 + 2.0% applicable for

1980 (NPL)* 1.932 x 105 Bq + 2.0% techneti um

EFFICIENCY TRACING 4tt3-Y(LS)

COBALT-60 (NBS) 1.962 x 105 Bq g 'J

+ 2.0% In progress

COBALT-60 (NPL)* 1.960 x 105 Bq r] + 0.5%

NIOBIUM-95 (NPL)* 1.964 x 105 Bq g

- 1 + 0.5%

COMPARATIVE METHOD 4tt3(LS)

USING LITERATURE DECAY

SCHEME DATA (NBS)

COBALT-60 In progress 4.409 x 104 Bq

NICKEL-63 1.926 x 105 + 2.5%

HYDROGEN-3 1.932 x 105 + 2.5% 4.419 xlO4 Bq

SCANDIUM- 46 1.939 x 105 + 2.5%

D. EFFICIENCY TRACING

MUTIPARAMETER FIT

Cesi um-134

Europium-154

In preparation

In progress

NATIONAL PHYSICAL LABORATORY, Great Britain

16
emits gamma rays in coincidence with beta particles is mixed with the

14

C or "Tc, and the counting officiency is varied by selecting* in turn,

lower thresholds for the height of electronic pulses derived from the

liquid scintillator. The counting rates for all selected gamma rays

and for those that are in time coincidence with beta particles can be

used to give a measure of the beta-particle-counting efficiency for that

radionuclide. An extrapolation of the total beta-particle count rate

as a function of efficiency to 100% efficiency is then used to measure

the total activity in the sample. Such extrapolations have given somewhat

inconsistent results in the past (see Method B of the table). The present

experiments include an "efficiency-tracing" radionuclide with several beta

groups for which the counting efficiency (for each) can be measured by

selecting coincidences with corresponding gamma rays. A multi parameter

extrapolation of the total beta count rate is then made to 100% efficiency

for each. The results obtained with multi parameter fitting will then be

checked against those of the first method.

. 4 Measurement of Absolute Sputtering Yields

J. Fine

Surface Science Division

Center for Chemical Physics

The principal aim of this work is to obtain absolute sputtering yields

of 1-5 keV ions on wel 1 -characterized elemental samples in order to improve

the accuracy of depth profiling measurements by current surface analysis

methods. The accuracy of depth profiling measurements is at present limited

by the availability of accurate, reliable, sputtering yield data and by the

lack of knowledge of the topographical and morphological effects produced

by ion bombardment.

a. Sputtering yields: Quartz oscillator weight-loss method

A significant improvement has been made in the method by which in situ , dynamic sputtering yields are measured. The third harmonic in the signal

from a gravity-crystal microbalance has been found to give greater accuracy

and stability than the fundamental in measurements of mass loss due to sputtering. A smaller area of the crystal can be used than before and more uniform incident ion-current densities can be achieved. New electronics for

third-harmonic detection from the oscillator have been designed and tested

and calibration of the system is underway.

b. Sputter depth profiling: Use of combined Auger and x-ray analysis

for determining elemental composition

Low-energy primary electrons (3-10 keV) are being used to excite x-ray

emission in thin metallic films (< 70 nm). These low-energy x rays, primarily

of less than 2 keV energy, have a depth sensitivity limited to about a single

such thin film layer and give information of the type and amount o^ material

contained in this thin surface layer. An ultra-thin windowed energy dispersive

ST ( Li ) detector is used to monitor this x-ray emission simultaneously ith the

17
1

KeV

Ar*

Bombardment oo

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4-> 4-

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to E

x: •<

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-ac e 0 0 4-O

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n3 CO 4-J -— OJ •<-

4-J CO fO O . O CL

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00

(sjmn Ajejnqje) A^sueiui
detection of Auger electrons so that at any point of a sputter depth

analysis it is possible to obtain both the composition of the surface

(Auger) as well as that of the underlying material near the surface.

This new application of the combined technique to a metallic thin film

system is providing new as well as more reliable depth data.

c. Development of SRM's for sputtering rate and depth profile analysis

The objective is to develop SRM's that would allow convenient

determinations of ion-beam sputter-removal rates in commonly used surfaceanalysis instrumentation. Thin film reference materials of known thickness

would be used to calibrate ion-gun current densities for particular operating conditions. This information together with sputtering-yield data for

a range of materials would establish depth scales in the measurement of

depth profiles.

As part of a joint U.S. /Yugoslavia program between J. Fine and NBS and

B. Navinsek at the J. Stefan Institute in Ljubjana, three types of thin-film

structures have been fabricated by sputtering-deposition in Yugoslavia:

1) a thin film oxide of tantalum produced by reactive sputter deposition

onto an in situ sputtered silicon substrate; 2) a multilayered Ni/Cr/Ni/Cr ... thin-film structure where the layers are about the same thickness 70 nm);

and 3) a multilayered Ni/Ag/Ni/Ag ... structure where the Ag layer is con- siderably thinner than the 50 nm Ni layer. These structures were also

deposited onto quartz oscillators so that sputtering yield measurements can

be obtained by the mass-loss method. Sputter depth-profile analysis using

Auger spectroscopy and x-ray fluorescence of the Ni/Cr and Ni /Ag structures

indicate that each layer is completely resolved and that very little degradation in depth resolution is observed in sputtering through all nine layers

of the structure. Results of such a depth profile analysis on the Ni/Cr

system are shown in Figure 2.1; these well-defined repetitive profiles

indicate the suitability of this multilayered material for sputter profile

calibration.

.5 Variation with Time of the Heat of Combustion of Coal

D. R. Kirklin

Chemical Thermodynamics Division

Center for Chemical Physics

Commercial laboratories need a powdered coal sample with a certified

heat of combustion to evaluate their calorimetric techniques and procedures.

SRM 1632a (bituminous coal) and SRM 1635 (sub-bituminous coal) are presently

being employed by commercial laboratories to calibrate their instruments and

to check their analytical techniques and procedures employed in the determination of trace elements in fossil fuels. The heats of combustion of

SRM's 1632a and 1635 are not certified because the long term stability (> 1 yr)

of the heats of combustion have not been rigorously established. Therefore,

the combustion calorimetry laboratory of the Chemical Thermodynamics Division

19
has measured the heats of combustion of SRM's 1632a and 1635 to determine

the variation of this important property with time.

The heat of combustion of SRM 1632a was measured in October 1979,

April 1980, and_June 1981. The mean heat of combustion was 26.388 MJ* kg" 1 (11 345 Btu* 1 b“

1

) _ i n October 1979 and when last measured in June 1981 was only 26.048 MJ* kg" 1 (11 199 Btu* lb" 1 ). This observed decrease of 146 Btu

exceeds the ASTM recommended intralaboratory repeatability of 50 Btu* lb’ 1

. This observed decrease of approximately 1.30 percent is believed to be due

to the slow oxidation of coal samples upon storage at laboratory conditions

The SRM coal samples are being stored under laboratory conditions,

oxidizing atmospheres, and inert atmospheres. The heats of combustion will

be remeasured in fiscal year 1982 to determine further the variation of the

heats of combustion of SRM coals with time.

.6 Modernization of Color Fading Standards

H. Okabe

Molecular Spectroscopy Division

Center for Chemical Physics

The NBS SRM's 702 and 703 are plastic chips containing quinoline

derivative dye. They have been used in the color and fabric industry

as simple and inexpensive standards for measuring the total output of

carbon arc lamps. Calibration has been made, however, in terms of an increase in transmittance as a function of Standard Fading Hours,

arbitrary units of exposure using the NBS master carbon arc lamp. This

project aims at providing an absolute standard for lamp output in terms

of joules*cm" 2 absorbed by the plastic plates.

The results of this work are: ( 1 ) fading rate of the plates measured

by the decrease of absorbance at 420 nm is independent of incident wavelengths, 366, 404.7, and 435.8 nm; (2) the quantum yield of fading is

initially 2 x 10‘ 5 and it decreases with exposure; (3) the fading rate

increases at higher temperature; and (4) the correlation between the

fading by lamp exposure and that by solar exposure is obtained using a filtered 1000 W Xe arc, a simulated solar radiation source. The fading

plates provide simple and inexpensive means to measure the integrated

lamp output and solar energy. More detailed information is contained

in a manuscript submitted to Applied Optics. Typical relationship

between the decrease in absorbance and energy absorbed is shown in the

figure 2. II for (A) 0.06" plate and (B) 0.124" plate.

20
Figure 2. II

21
Graphs (A) and (B) of Figure 2. II correspond to the following:

(A) Decrease in absorbance as a function of energy absorbed

by 0.06" plates; light sources are the filtered

(Corning CS1-75) 1000 W Xe lamp, O, non air cooled

plate, t, air cooled plate, and<] 435.8nm Hg line.

(B) Decrease in absorbance as a function of energy absorbed

by 0.124" plates; light sources are the filtered 1000

W Xe lamp, 0, non air cooled plate, •, air cooled plate,

and A » 366 nm Hg line, , 404.7 nm Hg line, ^ , 435.8 nm Hg

line. The corresponding solar exposure is calculated from

the fractions of solar energy absorbed by the plates.

22
.7 Sulfur in Metals by IDMS

W. R. Kelly and P. J. Paulsen

Inorganic Analytical Research Division

Center for Analytical Chemistry

The objective of this research was to develop an isotope dilution

mass spectrometric method for the determination of sulfur that would be

precise and accurate for copper and iron base materials containing less

than 20 yg/g. Thermal ionization of As 2 S 3 from silica gel was investigated and adopted because it promised to provide both a lower blank

and improved precision compared with the SSMS-ID procedure developed

last year. Classical chemical methods are not applicable at sulfur

concentrations below 50 yg/g. The new instrumental techniques have the

sensitivity to measure microgram amounts of sulfur; however, they rely

on standards of high concentration to determine a calibration curve which is extrapolated to low sulfur values. In this calibration procedure, a small error in the slope or an offset in the curve becomes

greatly magnified at low sulfur values.

In the development of this new technique, advantage was taken of

the knowledge gained from the isotope dilution spark source determinations

of Burke, Paulsen, Maienthal, and Lambert (1982). Techniques for spiking,

sample dissolution, and reduction of sulfate to H2 S were essentially

unchanged. The H 2 S was converted to As 2 S 3 instead of Ag 2 S. The As 2 S 3 was dissolved in NH 3 solution and loaded with silica gel onto single

rhenium

+

fi laments. The altered 32 S/ 34 S ratio was determined by measuring

the AsS ion currents. The measurement precision by this technique is

0.2 percent or better which represents at least a ten-fold improvement

compared to spark source determinations. Of equal importance is the

five-fold reduction in blank to 0.1 yg S. The variability in the blank

constitutes the largest source of uncertainty for samples containing

less than 20 yg/g of sulfur.

For high accuracy determinations of sulfur by isotope dilution, the

isotopic composition of sulfur must be determined in each sample. This

is necessary because the isotopic composition is variable in nature as a result of mass dependent fractionation during biological and geological

processes. The relative range in the 32 S/ 34 S ratio can be as large as

10 percent which could result in a bias of 2 percent in the calculated

sulfur concentration. This potential source of bias was eliminated by

measuring the isotopic composition of sulfur in each Standard Reference

Material. The range for the 32 S/ 34S in these materials was 2 percent.

As a demonstration of the potential of this new technique, the

sulfur content has been determined in two copper base and two pure

copper Standard Reference Materials. Individual values for one gram

replicates as well as the values for chemical blanks are given in

Table 2. IV. The average value of the blanks given in Table 2. IV is

0.14 yg and the range is 0.07 yg. If one were to assume that the range

was an estimate of the blank variability, then the overall uncertainty

would be about one percent for the SRM's containing 20 ppm sulfur and about

23
Table 2. IV. Sulfur Content in Copper Base SRM's as Determined by

Thermal Ionization Mass Spectrometry

Sample PS/2 Blank, ug

SRM 184 0.14, 0.18

2 17.3

3 17.7

4 17.4

5 16.6

Average = 17.3

SRM 52c

S-14 19.5 0.14

S-15 20.1

S-16 19.7

Average = 19.8

SRM 1035 Composite 0.11

1 22.3

2 22.2

3 22.2

Average = 22.2

SRM 1035 Samples from individual cans of 0.12

unpackaged material

Can 1 (top) 22.4

Can 1 (bottom) 22.3

Can 3 (top) 22.5

Can 3 (bottom) 22.5

Average = 22.4

SRM 1034 Composite 0.13

1 2.7

2 2.8

3 2.8

Average = 2.8

24
two percent for SRM 1034. These uncertainties include, in addition to

the blank variability, a 0.2 percent measurement and 0.25 percent spike

calibration uncertainty. This technique in its present form could

determine sulfur in metallic matrices at the 1 ppm level to better than

five percent. At the present time, this new technique stands alone in

its capability to determine accurately and precisely sulfur at the sub20 ppm level. In addition, it also has the capability to determine

sulfur at high concentrations (>0.1 percent sulfur) in biological and

fuel samples to better than one percent.

This new technique is being used to certify the following copper

and iron base Standard Reference Materials for sulfur: C1253, 394, High

Purity Fe Sponge, 131b, and 891.

.8 D.C, Plasma Spectrometry

M. S. Epstein

Inorganic Analytical Research Division

Center for Analytical Chemistry

Research has been directed towards the development of the dc plasma/

echelle spectrometer system as a tool for high accuracy analytical work.

The areas investigated have been:

(a) Characterization of the resolution capabilities of the echelle spectrometer relative to the broadened analyte-element plasma linewidths- - measured plasma linewidths were found to significantly limit the ultimate

resolution capabilities of the echelle.

(b) Thermal equilibration of the echelle spectrometer to promote longterm stabili ty- -spectrometer thermal gradients were correlated with heat

generated by the plasma, room temperature fluctuations, and exhaust

system flow rates to develop procedures which will stabilize the spectrometer throughput to at least ± 10 percent for a typical analysis time of

about four hours.

(c) Determination of low and high concentration noise sources- -b,y

determining the relative contributions of analyte and plasma flicker and

white noise and dark-current shot-noise to the total noise which limits

detection or precision, we have been able to optimize sampling times and

spectrometer slit widths.

(d) Evaluation of an ultrasonic nebulizer for sample introduction- -the

unmodified nebulizer was found to provide detection capabilities equivalent

to a pneumatic nebulizer with a slight degradation in precision. Addition

of a desolvation chamber and/or modification of the plasma sampleintroduction tube should produce a significant enhancement of detection

capability.

25
(e) Development of methods to correct for interelement interferences using

chemical buffers- -a requirement for close matrix-matching of acid concen- trations of standards and samples when lithium buffer solutions are used

was found.

The result of this work has been an understanding of some of the

parameters and mechanisms which influence accuracy using a dc plasma/echel le

spectrometer system. Based on this, procedures have been developed

which will provide better than ten percent accuracy without standard

addition procedures and accuracy to within one to two percent when

standard addition is employed. Results of this research were presented

by M. S. Epstein in an invited talk at the Eighth Annual Meeting of the

Federation of Analytical Chemistry and Spectroscopy Societies, Philadelphia,

PA, in September 1981.

.9 Quantitative Recovery of Iodine from Biological Matrices

T. J. Murphy

Inorganic Analytical Research Division

Center for Analytical Chemistry

The goal of this research has been the development of a quantitative

method for the recovery of iodine from biological matrices. Quantitative

separation is the key step in determining ultratrace levels of iodine in

biological SRM's by isotope dilution mass spectrometry.

A literature search of trace iodine separations was completed and

possible separation methods identified. Most of the effort has been

directed to the separation of iodine by quantitative oxidation of iodide

to iodate during the "wet-ashing" of botanical material. Various "wetashing" methods have been investigated including chloric acid, nitricsulfuric acids, fuming nitric-sulfuric acids, and fuming nitric-sulfuricperchloric acids. The latter two acid combinations proved to be the

most effective.

After destruction of the organic matrix and oxidation of iodide to

iodate, iodine can be separated by reduction to iodide and precipitation

as silver iodide or by reduction to iodine followed by distillation.

Preliminary experiments showed reasonable recovery of 200 to 500 yg

of iodide added to 1-g leaf samples, so attention was directed to recovery

of trace quantities of iodide from strong acid solutions by coprecipitation

of iodide with silver chloride. Experiments with 12

5

1 as a radio-tracer

showed that quantities of iodide as low as that contained in the tracer

(<1 mg I") could be recovered with better than 95 percent efficiency

when coprecipitated (from strongly acidic solutions) with ^4 mg of silver

chloride.

26
The recovery of trace iodide from botanical material was then

investigated. One gram samples of SRM 1572, Citrus Leaves, which con- tained about 2 yg/g I" were spiked with 12

5

1 and "wet-ashed" with fuming

nitric-sulfuric acids. The iodate resulting from this oxidation was reduced to iodide with hydrazine in sulfate, coprecipitated with silver

chloride, and removed from solution by filtration. The results of these

experiments showed that better than 90 percent of the iodide was re- covered by the coprecipitation with silver chloride.

The results of this investigation will be applied to the determination of iodide in SRM 1572 and other botanical SRM's by isotopic

dilution mass spectrometry.

. 1 0 Development of a Radiochemical Separation Procedure for Tin in

Biological SRM's

R. R. Greenberg

Inorganic Analytical Research Division

Center for Analytical Chemistry

Although tin has been shown to be essential for mammalian nutrition [1], it can be highly toxic in some forms [2]. Unfortunately, tin

cannot be readily determined in biological materials because of the

naturally occurring low levels. Relatively little reliable data con- cerning the tin concentrations in human and animal tissues and fluids

exists, and very few biological reference materials with known tin

concentrations are available. None of the eight NBS biological SRM's

issued have certified or "information only" values for tin. Biological

SRM's with certified tin concentrations would be of great value to

analysts wishing to determine tin.

Neutron activation analysis can be used to determine tin in most

biological materials, at the naturally occurring levels, if a radiochemical procedure is used to separate tin from interfering elements and

the background level of radiation (noise) is reduced. Both the 113 Sn

and M7mSn isotopes can be used to quantify tin if the interfering 160 Tb

(for 113 Sn) and 47 Sc (for 11?mSn) isotopes are removed. This has been

accomplished with a separation procedure based on the extraction of Snl 4 into toluene. The sample is initially dissolved with nitric, sulfuric,

and hydrofluoric acids along with hydrogen peroxide, followed by a filtration step to remove precipitated oxides and sulfates from the

final sulfuric acid solution before extraction into toluene. Carriers

are used to assure a quantitative recovery (>99.8 percent) and maximize

the decontamination.

Five samples of SRM 1571 (Orchard Leaves) have been analyzed by the

above procedure. The preliminary concentration value of 290 ± 17 (Is)

ng/g agrees favorably with two of the literature values (294 ± 16, and

290 ± 20, compiled by Gladney [3]. The reduction in background radiation

was better than a factor of 1000, and no Sc or Tb could be detected using

other, more intense, y-rays, indicating decontamination factors of >20,000

for Sc and >1,000 for Tb.

27
Research is continuing to further improve this method. A small

fraction of the selenium, M percent, accompanies the tin through the

separation and can elevate the background around the tin peaks in some matrices. Therefore, efforts will be directed at selenium reduction.

Other SRM's with lower tin concentrations, such as Bovine Liver (SRM 1577),

will be analyzed to evaluate the suitability of this procedure to provide

certification quality data for new SRM's.

References

:

[1]

Schwarz, K. , Milne, D. B., and Vinyard, E., Biochem . Biophys . Res . Commun . , 40 , 22 (1970).

[2] Schroeder, H. A., Environment , 13 , 18 (1971).

[3] Gladney, E. S., "Compilation of Elemental Concentration Data

for NBS Biological and Environmental Standard Reference

Materials," Los Alamos Informal Report LA-8438-MS (1980).

. 1 1 Development of ID/MS for Trace Concentrations of Vanadium

J. W. Gramlich and H. M. Kingston

Inorganic Analytical Research Division

Center for Analytical Chemistry

There have been few SRM's certified for vanadium due to the extremely

low levels of this element in most natural, biological, and environmental

materials (excluding fossil fuels). Many cases of vanadium toxicity

have been reported in connection with the use of fossil fuels. It is

significant that the most concentrated natural sources of vanadium are

fossil fuels such as oil and coal; in oil, it is often the major inorganic

component. Vanadium is also ubiquitous in industry in the form of

ferro-vanadium alloys or other species used in dozens of processes as the major catalyst. The development of an isotope dilution mass spectrometric (ID/MS) procedure to analyze vanadium will enable NBS to

certify this important element in a large variety of requested materials.

The first high accuracy measurement of vanadium by ID/MS was com- pleted during the year on proposed SRM 1634a, Trace Elements in Fuel

Oil. The newly developed chemical and mass spectrometric methods were

applied initially to this SRM because of its relatively high vanadium

concentration (^ 50 ppm). One-half gram samples were analyzed from each

of six different bottles of SRM 1634a. The results, reported below, show

a high degree of precision. Future efforts will be directed at the high

accuracy analysis of vanadium at concentrations below 1 ppm.

28
Vanadium Concentration in SRM 1634a, Trace Elements in Fuel Oil

Sample No. yg V/g

1 55.72

2 55.82

3 55.78

4 55.69

5 55.76

6 55.70

Average = 55.75

Range = 0.13

In developing the chemical procedure for determining vanadium by

isotope dilution, extensive research to decontaminate the spike material

( 50 V) was necessary. The isotope obtained for the spiking was found to

be unsuitable in its initial condition due to contamination by potassium

and other elements. A separation technique was developed to purify the

50 V isotope which also was tested for the removal of isobaric interferences; specifically, the mass 50 isotopes of titanium and chromium.

Before precise isotope ratio measurements were made, a thorough

investigation of the various modes of thermal ionization was completed.

Studies of the ionization patterns and efficiencies of vanadium revealed

distinct differences between several pretreatment methods and between

different molecular forms. The final form chosen for loading the sample

onto the mass spectrometer filaments was vanadium oxychloride; V0C1 3 is

believed to be its major constituent. This is produced by final treatrner

with HC10 4 and HC1 and filament drying with heat, in air.

The chemical separation of vanadium from other metals was based on the formation of the peroxide complex and the use of cation exchange

chromatography. The peroxide complex prevented the ion exchanging of

vanadium while reducing chromium to its tri valent state. The reduced

chromium, along with the other metals, remained bound by the ion ex- change column. The chemical separation, as well as sample preparation

and final vanadium specie adjustment, were done under Class 100 dear- room conditions. This procedure was found to produce blanks below 1 ng

while eliminating the chromium and titanium present at comparable

concentrations. During this separation, approximately 20 specific

elemental components, present at lower concentrations in the fuel oil

matrix were also removed. A series cf oxidative steps, employed as a pretreatment, resulted in a sample having uniform characteristics for mass spectrometric analysis.

29
,12 Metal -on-Quartz Filters

R. W. Burke

Inorganic Analytical Research Division

Center for Analytical Chemistry

This research was initiated as a result of inconsistency observed

in the transmittance of commercially-produced chromium-on-quartz filters

(SRM 2031) intended for use in the verification of the transmittance and

absorbance scales of ultraviolet and visible spectrophotometers. A

potential problem with this SRM was first noted when it was observed

that there was a correlation between the measured transmittance and the

particular filter holder position utilized in the high accuracy spectrophotometer for measurement. This correlation initially suggested

that the chromium film might not be sufficiently uniform since it was

known that the different holder positions did not present exactly the same portion of the filter to the incident radiation in every case. A more significant clue, however, turned out to be the observation that

the filters which exhibited the largest positional transmittance dependence also exhibited the largest differences when the transmi ttances

obtained with a tungsten source were intercompared with the transmittance values obtained with a deuterium source. This information clearly

was not consistent with an inhomogeneity problem and consequently

another explanation was necessary. Since, at a fixed wavelength and

spectral bandpass, these two radiation sources can differ most notably

only in their degree of polarization, it was surmised that the observed

problem could be due to a polarization effect in the filters. A sheet

polarizer was subsequently installed in the high accuracy spectrophotometer and the existence of a definite polarization effect was quickly

verified. Intercomparison of transmittance values obtained with 0 and

90° polarized radiation showed differences as large as 12 percent in the

worst instances. Systematic studies have since confirmed that this

polarization effect, when present, is a characteristic of the chromium

film itself rather than the result of any strains introduced by the

optical contact and related operations used in the assembly of these

"sandwich-type" filters. An alternate commercial laboratory is now being used to perform the metal coating. By spinning the quartz plate

and controlling more carefully the deposition parameters, the percentage

of filters that exhibit a polarization effect has been reduced from

about 50 percent to less than 10 percent.

. 1 3 Light Elements in Complex Matrices

R. M. Lindstrom and G. J. Lutz

Inorganic Analytical Research Division

Center for Analytical Chemistry

The intent of this project was to establish the validity of nuclear

methods of analysis for light elements (H, B, C, N, A1 , Si, and S) in

30
SRM's from natural sources. To accomplish this, it is necessary to show

reproducibility in the analysis of simple substances, detection and

elimination of interelement interferences, and accuracy in the analysis

of known materials of complex composition.

The primary analytical method used is neutron-capture prompt gammaray activation analysis (PGAA), building upon the procedures developed

at the NBS reactor by workers at the University of Maryland and NBS.

Measurements of carbon were also performed by instrumental photon

activation analysis (IPAA) at the NBS Linear Accelerator.

High purity urea (SRM 912 and Ultrex), tris buffer (SRM 922 and

Baker), SRM 17 sucrose, ammonium sulfate (Spex and Johnson Matthey),

graphite, and elemental sulfur were used as standards for C, H, N, and

S. Samples of SRM 1632a and 1635 coal, 1634 fuel oil, n-octyl sulfide,

and a suite of Nigerian coals were analyzed by PGAA. The SRM coals also were analyzed by IPAA, using two different high purity graphites as standards.

The usefulness of the technique is determined by the sensitivity

(in units of counts/second per gram of element) and by the background.

These parameters were evaluated as follows:

Element

Best

Energy

keV

Sensitivity

counts/sec*g

Background

counts/sec

Determination

limit for

10 hr. Irrad.

H 2223.3 688 ± 30 2.578 ± .005 35 yg

B 477.6 418000 0.986 ± .007 0.03 yg

C 1261.9 0.326 ± .008 0.0054 ± .0016 2.8 mg

N 1884.8 2.38 ± .02 0.078 ± .002 1 . 4 mg

S 840.4 40.45 ± .07 0.12 0. 1 mg

Irradiations for these elements in SRM's and other samples have been

completed. Each analytical line in the gamma-ray spectrum may be subject

to interferences from nearly-coincident lines due to another element. A

correction for these interferences can in general be made by observing a clean line of the interfering element. Assessment of the magnitudes and

uncertainties of these corrections are the major task to be concluded in

the final phase of data analysis. Counting of coals for the IPAA

determination of carbon is in progress.

31
.14 Two-Dimensional Proton NMR Spectroscopy of Hydroxyl Proton Coupled

a- and g-D-Gl ucopyranose

B. Coxon

Organic Analytical Research Division

Center for Analytical Chemistry

Solutions of a- and 3-D-glucose in dimethylsulfoxide-cU (DMS0-d_6 ) are of

interest as stable systems for the quantitative analysis of D-glucose (dextrose)

SRM's by proton and carbon-13 NMR. However, inhibition of hydroxyl proton

exchange in these solutions results in complex 12-proton spin systems that are difficult to interpret by conventional techniques. The proton NMR spectra of

the major and minor components of SRM D-glucose (a-D-gl ucopyranose and

3-D-glucopyranose, respectively) in DMS0-d 6 solutions have now been analyzed

completely by application of the two-dimensional, 'J'-resolved technique at

400 MHz. One great advantage of this technique is the separation of chemical

shift and coupling constant information into different dimensions, which

allows complex, overlapping proton signals to be disentangled by cross-sectionshift between these signals.

The complete, two-dimensional proton NMR spectrum of 3-D-glucose in

DMS0-d 6 solution is shown in Figure 2. III. Display of the ' J ' -spectra cross- sections of the 3 anomer (see Figure 2. IV) permits the separation of all spin

multiplets except the doublets due to HO-2 and HO-3, the chemical shifts of

which are accidentally coincident under these conditions. Complete coupling

constant data obtained by measurement of the 'J'-spectra cross-sections for

both a and 3 anomers are shown in Table 2.V.

Table 2.V. Proton Coupling Constants (Hz) of a- and 3-D-Glucopyranoses in

DMS0-d_6 Solutions, Measured by 2-D NMRa at 400 MHz.

Anomer J l,2

J 2,3J 3,4

J

4,5

J 5,6J 5,6‘ J 6,6'

a 3.6 9.7 8.7 9.7 2.3 5.0 11.2

3 7.7 8.9 8.5 9.4 2.2 5.9 11.8

Anomer J 1,H0-1

4!

°2,H0-1

J 2,H0-2 ^3, HO-3J 4,H0-4J 6,H0-4J

6‘ ,H0-6

a 4.8 1.2 6.6 4.8 5.4 5.2 1 6.4

3 6.6 0 4.7 4.8 4.9 5.5 6.3

a Data size: 8K x 128; Digital resolution in 'J' domain: 0.24 Hz/point.

These spectral analyses have been confirmed by other experiments in which

simplified spectra were obtained for a- and 3-D-glucopyranose by addition of one drop of trifluoroacetic acid to the DMSO-dJ solutions. This procedure

greatly increased the rate of hydroxyl proton exchange, and thereby removed

32
Figure

2.

Ill

2D

J-resolved

proton

NMR

spectrum

of

3-D-glucose

in

DMS0-d

6

at

400

MHz.
Figure

2.

IV

2D

NMR

J-spectra

at

400

MHz,

B-D-glucose

in

DMS0-d

6

,

hydroxyl

protons

coupled.
the hydroxyl proton coupling constants from the CH proton spin multi pi ets.

The addition of a catalytic quantity of trifluoroacetic acid also speeded

anomerization, so that for additional confirmation of the spectral assignments

of individual anomers by homonuclear spin decoupling, automated sequences of seven double-resonance experiments were performed, within 7-9 min after the

addition of the acid, before significant anomerization had occurred.

The vicinal CH proton coupling constants indicate that a- and 3 -Q-glucopyranose both adopt the 4 C^ chair' conformation in DMS0-d 6 solution. Specific

evidence for existence of the a-anomer in conformation (A), shown below, in

which H-2, C-2, C-l, 0-1, and HO-1 adopt a planar 'W' -arrangement , is afforded

by observation of the unusual long-range coupling constant, J 0 un , 1.2 Hz.

c , HU- I a-D-GLUCOSE, ‘W’-COUPLING

J2, ho-1 1 -2 Hz

A

0

H

35
This coupling constant is not observed for the 3-anomer, and, in fact, the

planar 'W' -arrangement is sterically impossible in this anomer. The favored

orientation of HO- 1 in the a-anomer may be attributed to steric crowding of

HO- 1 by DMSO-cU molecules hydrogen bonded to HO-2 and HO-3.

The efficiency of data acquisition for both one- and two-dimensional NMR

depends on the proton spin-lattice relaxation times (T i ) of the sample, since

the pulse sequence cannot normally be repeated at intervals of less than 5T i

.

Therefore, the proton Ti values of a- and 3-Q-glucopyranose have been measured

under the conditions used for the two-dimensTonal spectroscopy. The inversionrecovery method was used together with analysis of the data by means of an iterative, three-parameter exponential fit. The Ti results are shown in

Table 2. VI. For solutions of the anomers in DMS0-d 6 , the pyranoid ring protons

show Ti values in the range 0.5-0. 7 s, the methylene protons values of 0.3 s, and the hydroxyl protons, 0.9- 1.1 s. This interesting difference between ring

(CH) protons and hydroxyl protons may be due to either greater mobility of the

hydroxyl protons (shorter correlation time), or to association (by hydrogen

bonding) of the hydroxyl protons with solvent molecules containing deuterium

nuclei that are relatively poor relaxers of protons. Measurements of solutions

of a- and 3-Q-glucose in non-deuterated dimethyl sulfoxide are in progress, to

test these hypotheses. However, the results indicate that the pulse sequence

for two-dimensional NMR should not be repeated more often than once every

5.5 s.

Table 2. VI Proton Spin Lattice Relaxation Times (T x , 3-D-Glucopyranosesa at 400 MHz.

Sec) of a- and

Anomer H-l H-2 H-3 H-4 H-5 H-6 H-6 1 HO- 1 HO-2 HO-3 HO-4 HO-i

a 0.7 0.6 0.6 0.6 0.5 0.3 0.3 0.9 1.1 1.0 0.9 1.0

3 0.6 0.7 0.6 0.6 0.6 0.3 0.3 1.1 1.0 1.0 0.9 1.1

Concentration: 100 mg of a-- or 3-D-glucose in DMS0-d 6 (1.0 mL)

.

36
the hydroxyl proton coupling constants from the CH proton spin multi pi ets.

The addition of a catalytic quantity of trifluoroacetic acid also speeded

anomerization, so that for additional confirmation of the spectral assignments

of individual anomers by homonuclear spin decoupling, automated sequences of seven double-resonance experiments were performed, within 7-9 min after the

addition of the acid, before significant anomerization had occurred.

The vicinal CH proton coupling constants indicate that a- and 3 -Q-glucopyranose both adopt the 4 Ci chair' conformation in DMS0-d 6 solution. Specific

evidence for existence of the a-anomer in conformation (A), shown below, in

which H-2, C-2, C-l, 0-1, and HO- 1 adopt a planar 1 W' -arrangement , is afforded

by observation of the unusual long-range coupling constant, J 0 u « , 1.2 Hz.

c , HU- I a-Q-GLUCOSE, ‘W’-COUPLING

J2, ho-1 1.2 Hz

4

H

A

35
This coupling constant is not observed for the 3-anomer, and, in fact, the

planar 'W -arrangement is sterically impossible in this anomer. The favored

orientation of HO- 1 in the a-anomer may be attributed to steric crowding of

HO- 1 by DMS0-d 6 molecules hydrogen bonded to HO-2 and HO-3.

The efficiency of data acquisition for both one- and two-dimensional NMR

depends on the proton spin-lattice relaxation times (Ti) of the sample, since

the pulse sequence cannot normally be repeated at intervals of less than 5T i

.

Therefore, the proton Ti values of a- and 3-Q-glucopyranose have been measured

under the conditions used for the two-dimensional spectroscopy. The inversionrecovery method was used together with analysis of the data by means of an iterative, three-parameter exponential fit. The Ti results are shown in

Table 2. VI. For solutions of the anomers in DMS0-d^6 > the pyranoid ring protons

show Ti values in the range 0.5-0. 7 s, the methylene protons values of 0.3 s, and the hydroxyl protons, 0.9- 1.1 s. This interesting difference between ring

(CH) protons and hydroxyl protons may be due to either greater mobility of the

hydroxyl protons (shorter correlation time), or to association (by hydrogen

bonding) of the hydroxyl protons with solvent molecules containing deuterium

nuclei that are relatively poor relaxers of protons. Measurements of solutions

of a- and 3-Q-glucose in non-deuterated dimethyl sulfoxide are in progress, to

test these hypotheses. However, the results indicate that the pulse sequence

for two-dimensional NMR should not be repeated more often than once every

5.5 s.

Table 2. VI Proton Spin Lattice Relaxation Times (T ls

3-Q-Glucopyranosesa at 400 MHz.

Sec) of a- and

Anomer H-l H-2 H-3 H-4 H-5 H-6 H-6 ' HO- 1 H0-2 HO-3 HO-4 HO-i

a 0.7 0.6 0.6 0.6 0.5 0.3 0.3 0.9 1.1 1.0 0.9 1.0

3 0.6 0.7 0.6 0.6 0.6 0.3 0.3 1.1 1.0 1.0 0.9 1.1

Concentration: 100 mg of a-- or 3-D-glucose in DMS0-d 6 (1.0 ml).

36
the hydroxyl proton coupling constants from the CH proton spin multi pi ets.

The addition of a catalytic quantity of trifluoroacetic acid also speeded

anomerization, so that for additional confirmation of the spectral assignments

of individual anomers by homonuclear spin decoupling, automated sequences of seven double-resonance experiments were performed, within 7-9 min after the

addition of the acid, before significant anomerization had occurred.

The vicinal CH proton coupling constants indicate that a- and 3 -Q-glucopyranose both adopt the 4 Cj chair' conformation in DMS0-d 6 solution. Specific

evidence for existence of the a-anomer in conformation (A), shown below, in

which H-2, C-2, C-l, 0-1, and HO-1 adopt a planar 'W' -arrangement , is afforded

by observation of the unusual long-range coupling constant, J 0 un , 1.2 Hz.

C , HU- I a-D-GLUCOSE, ‘W’-COUPLING

GH2OH

J2, HO-i 1-2 Hz

35
This coupling constant is not observed for the 3-anomer, and, in fact, the

planar 'W -arrangement is sterically impossible in this anomer. The favored

orientation of HO- 1 in the a-anomer may be attributed to steric crowding of

HO- 1 by DMSO-de molecules hydrogen bonded to HO-2 and HO-3.

The efficiency of data acquisition for both one- and two-dimensional NMR

depends on the proton spin-lattice relaxation times (Ti) of the sample, since

the pulse sequence cannot normally be repeated at intervals of less than 5T X. Therefore, the proton T x values of a- and 3-Q-glucopyranose have been measured

under the conditions used for the two-dimensional spectroscopy. The inversionrecovery method was used together with analysis of the data by means of an iterative, three-parameter exponential fit. The T x results are shown in

Table 2. VI. For solutions of the anomers in DMSO-de* the pyranoid ring protons

show Ti values in the range 0.5-0. 7 s, the methylene protons values of 0.3 s, and the hydroxyl protons, 0. 9-1.1 s. This interesting difference between ring

(CH) protons and hydroxyl protons may be due to either greater mobility of the

hydroxyl protons (shorter correlation time), or to association (by hydrogen

bonding) of the hydroxyl protons with solvent molecules containing deuterium

nuclei that are relatively poor relaxers of protons. Measurements of solutions

of a- and 3-D-glucose in non-deuterated dimethyl sulfoxide are in progress, to

test these hypotheses. However, the results indicate that the pulse sequence

for two-dimensional NMR should not be repeated more often than once every

5.5 s.

Table 2. VI Proton Spin Lattice Relaxation Times (Ti, Sec) of a- and

3-Q-Glucopyranosesa at 400 MHz.

Anomer H-l H-2 H-3 H-4 H-5 H-6 H-6' HO1

H0-2 HO-3 HO-4 HO-6

a 0.7 0.6 0.6 0.6 0.5 0.3 0.3 0.9 1.1 1.0 0.9 1.0

3 0.6 0.7 0.6 0.6 0.6 0.3 0.3 1.1 1.0 1.0 0.9 1.1

Concentration: 100 mg of a- or 3-Q-glucose in DMS0-d 6 (1.0 mL).

36
the hydroxyl proton coupling constants from the CH proton spin multi pi ets.

The addition of a catalytic quantity of trifluoroacetic acid also speeded

anomerization, so that for additional confirmation of the spectral assignments

of individual anomers by homonuclear spin decoupling, automated sequences of seven double-resonance experiments were performed, within 7-9 min after the

addition of the acid, before significant anomerization had occurred.

The vicinal CH proton coupling constants indicate that a- and B-D-glucopyranose both adopt the 4

C_i chair

- conformation in DMS0-d 6 solution. Specific

evidence for existence of the a-anomer in conformation (A), shown below, in

which H-2, C-2, C-l, 0-1, and HO- 1 adopt a planar 'W' -arrangement, is afforded

by observation of the unusual long-range coupling constant, J 0 un , 1.2 Hz.

c. , HU- I a-Q-GLUGOSE, ‘W’-COUPLING

CH2 OH

J2, ho-1 1-2 Hz

35
This coupling constant is not observed for the 3-anomer, and, in fact, the

planar 'W' -arrangement is sterically impossible in this anomer. The favored

orientation of HO- 1 in the a-anomer may be attributed to steric crowding of

HO- 1 by DMSO-de molecules hydrogen bonded to HO-2 and HO-3.

The efficiency of data acquisition for both one- and two-dimensional NMR

depends on the proton spin-lattice relaxation times (Ti) of the sample, since

the pulse sequence cannot normally be repeated at intervals of less than 5Tj.

Therefore, the proton Ti values of a- and 3-Q-glucopyranose have been measured

under the conditions used for the two-dimensional spectroscopy. The inversionrecovery method was used together with analysis of the data by means of an iterative, three-parameter exponential fit. The Ti results are shown in

Table 2. VI. For solutions of the anomers in DMS0-d 6> the pyranoid ring protons

show Ti values in the range 0.5-0. 7 s, the methylene protons values of 0.3 s, and the hydroxyl protons, 0. 9-1.1 s. This interesting difference between ring

(CH) protons and hydroxyl protons may be due to either greater mobility of the

hydroxyl protons (shorter correlation time), or to association (by hydrogen

bonding) of the hydroxyl protons with solvent molecules containing deuterium

nuclei that are relatively poor relaxers of protons. Measurements of solutions

of a- and 3-Q-glucose in non-deuterated dimethyl sulfoxide are in progress, to

test these hypotheses. However, the results indicate that the pulse sequence

for two-dimensional NMR should not be repeated more often than once every

5.5 s.

Table 2. VI Proton Spin Lattic

3-D-G1 ucopyranoses

9 e Relaxation Times (Ti

at 400 MHz.

, Sec) of a- and

Anomer H-l H-2 H-3 H-4 H-5 H-6 H-6' HO- 1 HO-2 H0-3 HO-4 HO-i

a 0.7 0.6 0.6 0.6 0.5 0.3 0.3 0.9 1.1 1.0 0.9 1.0

3 0.6 0.7 0.6 0.6 0.6 0.3 0.3 1.1 1.0 1.0 0.9 1.1

Concentration: 100 mg of a- or 3-Q-glucose in DMS0-d 6 (1.0 mL)

.

36
.15 Comparison of Two Isotope Dilution Definitive Methods for the Deter - mination of Glucose in Serum and Evaluation of the AACC Reference

Method for Glucose

A. Cohen, H. S. Hertz, J. Mandel , R. Schaffer, L. T. Sniegoski, T. Sun,

M. J. Welch, E. White, V

Organic Analytical Research Division

Center for Analytical Chemistry

The measurement of serum glucose levels is one of the most important and

most commonly performed analyses in the clinical laboratory. Clinical chemists

employ many different methods to determine serum glucose levels. When these

methods are compared on serum pools, serious discrepancies are found in the

results. Methods of demonstrated high accuracy and precision are needed to

provide an accuracy base to which the clinical methods can be compared. The

Center for Disease Control undertook the development of a reference method

with which clinical laboratories could evaluate their procedures. To establish the accuracy of the proposed reference method [a modified hexokinase/

glucose-6-phosphate dehydrogenase (HK/G6PDH) procedure], the Standards

Committee of the American Association for Clinical Chemistry asked NBS to

develop an isotope dilution mass spectrometric (ID/MS) definitive method for serum glucose.

A brief description of the first ID/MS method for serum glucose developed

at NBS is as follows: A known weight of uniformly labeled 13 C-glucose is

added to a known weight of serum. After the serum is allowed to equilibrate,

it is freeze-dried. The serum is then treated with acetone under anhydrous

conditions to convert glucose into 1 ,2:5,6-di-0-isopropyl idine-a-D-glucofuranose (DAG). Three thin-layer chromatography steps are employed to

separate DAG from other reaction products including the acetone-condensation

products with other hexoses. For the initial comparison of this method with

the reference method, samples were introduced to the mass spectrometer via the

direct insertion probe. All later work involved sample introduction via

packed column gas chromatography. Measurements are made on a low resolution

magnetic sector instrument operated in the electron impact (El) mode.

Magnetic switching is employed in the sequential monitoring of the (M-15)

ions for the labeled and unlabeled DAG. The measured unlabeled/labeled ratio

from serum samples is compared with the measured ratios of calibration standards, which consist of known weights of SRM glucose and uniformly labeled

13 C-glucose, converted to DAG. For quantitation, each sample measurement is

bracketed by measurements of the two calibration standards whose ratios most

closely bracket that of the sample. Linear interpolation is then used to

calculate the amount of glucose in the sample.

The results of the initial comparison of our ID/MS method with the

HK/G6PDH reference method is summarized in Table 2. VI I. The reference method

results are a composite of the results obtained from twelve laboratories,

including NBS, on five serum pools analyzed in quadruplicate over a five-day

period. The results demonstrate that the methods agree well for all pools

tested. A full report of this study is undergoing review for publication as an NBS 260 report.

37
Table 2. VII Comparison of Candidate Reference Method Results with ID/MS

Target Values. Differences and Standard Deviations in mg/L.

Manual

5

- ID/MS Semi-Automatedb

- ID/MS

Pool Mean Difference S.E.D.

C Difference S.E.D.

C

409.0 4.4 4.5 8.9 2.9

785.8 7.6 5.5 4.1 4.0

1344.4 - 1.1 7.3 - 3.0 6.3

1969.7 -19.2 9.8 -32.2 9.0

2978.7 -36.9 13.9 -48.6 13.6

Candidate reference method with manual pipetting.

Candidate reference method with semi -automated pipetting.

c Standard error of the difference.

A second ID/MS method was devised to provide a much simpler wet chemical

procedure as well as to verify the accuracy of the DAG method. This approach

utilizes the same labeled glucose, but differs markedly otherwise. After

equilibration, the serum is treated with ethanol to precipitate protein and

the deproteinized serum is freeze-dried, treated with 1 -butyl boronic acid in

anhydrous pyridine followed by acetic anhydride to form the derivative, a-Dglucofuranose cyclic 1 ,2:3,5-bis-(butylboronate)-6-acetate (glucose BBA).

Separation of glucose BBA from the BBA derivatives of other monosaccharides is

accomplished by gas chromatography using a 100 m SCOT capillary column.

Measurements are made in the electron impact mode, using the (M-57) ion,

which is a prominent fragment ion for glucose BBA but only a minor fragment

ion in the mass spectra of other hexose BBA's. Bracketing of the samples

with similarly derivatized calibration standards is again used for quantitation. Table 2. VI 1 1 shows the results for the comparison of the two ID/MS methods,

methods, at NBS, with the reference method, performed simultaneously at CDC, on three human serum pools.

Table 2. VI 1 1 Comparison of the Two ID/MS Derivative Methods and the CDC

Reference Method on Three Human Serum Pools Sampled

Simultaneously. Mean Results are in mg Glucose/g Serum.

DAG Glucose BBA HK/G6DH

Pool Mean CV (%) Mean CV (%) Mean CV {%)

A 0.6843 0.29 0.6779 0.19 0.6845 0.51

B 1.803 0.15 1.790 0.17 1.794 0.29

C 2.919 0.24 2.901 0.18 2.912 0.22

The agreement of all three methods is excellent (<1 percent range for

each pool). To check for interferences, samples from each pool were

remeasured under

+ isobutane chemical ionization (Cl) conditions, with monitoring of the (M+l) ions for both DAG and glucose BBA samples. The Cl results

agreed with the El results within the uncertainties of the measurements.

38
Our results have shown that both ID/MS methods are very precise, and

after exhaustive testing, we have found no bias sufficient to interfere with

the intended uses of either method. Therefore, each method satisfies the

requirements for a definitive method. However, when the two are compared on identical serum samples, the DAG results are consistently higher than the

glucose BBA results by a small but statistically significant amount (<1 percent for all pools tested). When compared on an aqueous glucose solution,

the two methods agree within the uncertainties of the measurements. Therefore, the small systematic difference observed is related to the presence of

the serum matrix. The two ID/MS methods have been described in a manuscript

to be submitted to Biomedical Mass Spectrometry . The excellent agreement of

the KH/G6PDH results with the ID/MS definitive method values proves that the

CDC method fulfills the requirements of a reference method.

.16 Comparison of Two ( I DMS ) Methods for Determination of Total

Serum Cholesterol

A. Cohen, H. S. Hertz, J. Mandel , R. Paule, R. Schaffer,

L. T. Sniegoski, M. J. Welch, E. White, V

Organic Analytical Research Division

Center for Analytical Chemistry

Both U.S. and international societies for clinical chemistry recognize

the need for definitive (i.e., essentially bias-free and highly precise)

methods that can serve, along with high-purity SRM's, as the accuracy base for

clinical chemistry. NBS has developed a candidate definitive method for total

serum cholesterol involving ID/MS. Our publication [ Clin . Chem . 26 , 854-860

(1980)] provides data that show the absence of interferences in the ID/MS

measurements involved in the method and the high reproducibility of the

results, thus demonstrating the method's accuracy and precision. To ensure scientific validity, we sought external confirmation by comparison with

another laboratory.

Researchers at the Karol inska Institute (KI), Stockholm, Sweden, who were

the first to report an ID/MS method for total cholesterol [1], used their

method to analyze samples of the same serum pools as were run at NBS. Their

analyses gave results with mean values consistently lower than the NBS values

for those pools. NBS study of the cholesterol used at the KI as primary

standard revealed that it contained lathosterol, an isomer of cholesterol that

interfered with the KI measurement method. When the KI reanalyzed the serum

pools with SRM cholesterol used as the primary standard, the bias was no longer evident, with mean values for the pools ranging from 1.5 percent below

to 1.5 percent above the NBS mean values (Table 2. IX). The imprecision of the

results obtained at the KI was about the same for the two series of analyses

and were from three to ten times larger than the NBS values. Several aspects

of the KI method have been identified as contributing to the imprecision.

39
Although no systematic bias is now apparent between the two methods, the

imprecision of the KI method limits its usefulness for confirming the accuracy

Table 2. IX Total Cholesterol Concentrations as the Mean ± One Standard Deviation of the Mean in mmol/L, for Five Serum Pools, as Determined by

ID/MS in Two Series of Analyses at the Karol inska Institute (KI)

and One at the National Bureau of Standards (NBS).

Laboratory Pool

N

a A B C D E

KI/firstc series 8 3.39 ± . 058b 4.68 ± .036 6.11 ± .046 7.35 ± .054 8.59 ± .088

KI/secondd

series 8 3.39 ± .019 4.73 ± .059 6.15 ± .046 7.57 ± .112 8.85 ± .064

NBS 16 3.43 ± .006 4.72 ± .008 6.15 ± .011 7.47 ± .011 8.79 ± .015

a N is the number of measurements per pool.

h

“Calculated from an analysis of variances [2].

cAnalyses performed without SRM Cholesterol as the primary standard.

rl“Analyses performed with SRM Cholesterol as the primary standard.

of the NBS method as a definitive method. (The KI method was not designed to serve as a definitive method.) Conversely, the NBS method, which has been

rigorously tested for accuracy in-house, does prove that the KI method fulfills

the accuracy requirements of a reference method. The comparison of these

ID/MS methods has been described in a manuscript submitted to Clinical

Chemistry .

References

[1] I. Bjorkhem, R. Blomstrand, and L. Svensson, Clin . Chim . Acta

54, 185 (1974).

[2] J. Mandel and R. Paule, Anal . Chem . 42 , 1194 (1970).

40
.17 Methods Development for the Analysis of Organic Nutrients in Food

J. M. Brown-Thomas and S. A. Margolis

Organic Analytical Research Division

Center for Analytical Chemistry

The primary objective of this program was to develop and evaluate

analytical methods for the analysis of fat and water soluble vitamins in

a food matrix which might in the future be used as a Standard Reference

Material. Our initial investigations have involved the determination of

vitamin D, nicotinic acid, nicotinamide, and thiamin in a nonfat dried

milk sample. The methods developed involved initial isolation of vitamins

from the matrix by solvent extraction, followed by high performance liquid

chromatographic analysis.

a. Vitamin P 2 (Fat-Soluble Vitamin) The method of sample preparation

for the analysis of vitamin D 2 utilized an enzymatic hydrolysis of the

lipid component of the sample at neutral pH. After pH adjustment of the

hydrolysate to 7.7, fatty acids were freed from the matrix by solvent

extraction.

High performance liquid chromatography (HPLC) was used for separation

of the D 2 and D 3 forms of the vitamin. Figure 2.V shows this separation from

a synthetic mixture and Figure 2. VI gives the chromatographic analysis of

vitamin D 2 in a milk extract using the method described above.

Final quantitation analysis of vitamin D 2 has not yet been achieved.

However, the level of concentration of the vitamin has been determined to

be at the low (<50) parts-per-billion level. Further application of the

technique will be the analysis of other selected fat-soluble vitamins in

this matrix.

b. Nicotinic Acid, Nicotinamide, and Thiamin (Water-Soluble Vitamins)

Sample preparation consisted of a 30 min. heat treatment in the presence

of 0.5 mol/L H 3 PO4 or CaOH (sat). The resulting solution was adjusted to

pH 3-4, passed through a small octadecylsilane (C-18) column and analyzed

by HPLC.

Two HPLC systems have been developed for analysis of these extracts.

One system involves the use of a cyano (CN) column and a' phosphate/acetonitrile mobile phase; the other system uses a Cl 8 column in conjunction

with a tetrabutyl ammonium acetate/acetonitrile mobile phase. Figures 2. VI

I

and 2. VIII are chromatograms of the nicotinic acid extracts. Figure 2. VII

is a chromatogram from unspiked milk and 2 . VI I I is a chromatogram from milk

spiked with 50 yg/g of nicotinic acid. These data suggest that the milk

sample did not contain detectable levels of nicotinic acid although microbiological assay showed 10 yg/g nicotinic acid. We are now working to

resolve this discrepancy.

Both chromatographic systems resolve nicotinamide, nicotinic acid, and

thiamin. Future work will be focused on quantitative analysis of these

compounds.

41
JFigure 2.

CM <r O Q

K f

CO O

O K

V Separation of Vitamins D 2 and D 3 using a Varian MCH-10 column.

Mobile Phase -10% methanol in acetonitrile

Detection - UV (267 nm)

42

STOP
INJ

START

Figure 2. VI Analysis of Vitamin D 2 in a milk extract using a Varian MCH-10

column

Mobile Phase - 10% methanol in acetonitrile

Detection - UC (267)

43
26 20

min.

T"

10

Figure 2. VII Acid extracted sample of dried milk powder.

44

261

n

m
Figure 2. VIII Acid extracted sample of dried milk powder + 50 yg of nicotinic

acid.

45

nm
.18 Surface Reactions Related to Instability of Compressed Gas Mixtures

R. Miller and E. Hughes

Gas and Particulate Science Division

Center for Analytical Chemistry

The work during the past six months has been directed primarily toward

an evaluation of the desorption of organic molecules from the inner surfaces

of gas containers. This work is considered of high priority because of a problem with certain SRM's in which the slow desorption of organics has

become evident as the age of the samples increase. These organics probably

were absorbed on valves on cylinder walls at some time prior to filling

with the SRM mixture and become evident only after a long period of time

when the concentration became great enough to measure.

A number of experiments have been performed to isolate the source of

the contaminant organics. The preponderance of evidence is that a significant portion of the organics are halogenated hydrocarbons. Trichloroethylene has been identified as a surface contaminant of several valves which

had not been previously used. The tentative conclusion was that trichloroethylene had been used as a degreasing agent at some time during fabrication.

Attempts to remove all traces from contaminated valves were partially successful and it was found that the valve seat - a small disk of polymeric material - was a major source of the desorbing organic. When the contaminated seat is

replaced with a seat never exposed to organics the concentration of the

contaminant is markedly reduced. However, contaminated seats which were washed with alcohol, rinsed with distilled water and baked at 100 °C for eight

hours still showed evidence of contamination although a significant reduction

occurred.

We plan to continue the experiments with valves in order to prepare a remedy which can be implemented easily by the specialty gas industry. In

addition we expect to begin a series of experiments to define the effect on stability of the container condition prior to filling. We will screen a large number of mixtures - both those known to be stable and those known to

be stable and those known to be unstable - for water content on the preliminary

assumption that the level of water vapor reflects the effort involved in

cleaning and drying the cylinder prior to filling.

46
.19 Thin Film Calibration Standards for Microanalysis

E. B. Steel, E. E. Newbury and P. A. Pella

Gas and Particulate Science Division

Center for Analytical Chemistry

Analytical electron microscopy is a rapidly emerging and highly

important microanalysis technique. Combining aspects of high resolution

microscopy, diffraction, and chemical characterization on a scale of 10 nm or less analytical electron microscopy impacts a vast spectrum of scientific

and technological disciplines, including materials science, biology, medical

studies, semiconductor technology, solid state physics, catalyst analysis,

and chemistry. The AEM chemical analysis methods are, however, limited by

an almost total lack of appropriate standards.

The purpose of this research program is to develop appropriate standards

for the microanalysis techniques of analytical electron microscopy (AEM).

These techniques include energy dispersive x-ray spectrometry (EDS) (for

determining elemental constituents with I >_ 11) and electron energy loss

spectrometry (EELS for l >_ 3). Standards for analytical electron microscopy must be films with a thickness of the order of 100 nm and lateral

dimensions to fit a 3-mm diameter circle. The desired elemental constituents differ depending on the analytical technique in question. For EDS work,

it is desirable to have a standard with six or more elements selected such

that their characteristic x-ray lines span the range of analytical interest,

1-10 keV. For EELS work, it would be useful to have standards containing

lithium, beryllium, boron, carbon, nitrogen, oxygen, and fluorine.

Research activity in FY81 was directed toward producing compositions

with low self-absorption of x rays which are appropriate for energy dispersive

x-ray spectrometry and electron energy loss spectrometry. Three glass sputtering targets, with the bulk compositions listed in Table 2.X have been

prepared. Glass K-411 in Table 2.X is a bulk Standard Reference Material

(SRM 470).

The K-411 glass target has been sputtered to prepare 60 transmission

electron microscope grids as a candidate thin film standard for a round

robin analysis. The glass was sputtered onto a thin (20 nm) carbon film

carried on a copper grid. A layer approximately 80 nm thick, as determined

by double beam interferometry, was deposited. The thickness appears to be

uniform from grid to grid. The thickness was chosen to eliminate the problems

of absorption and fluorescence which were encountered with lead glass samples

prepared in conjunction with P. Pella in FY80. This thickness gives a good

peak-to-background in the EDS spectrum (Figure 2. IX). Aluminum and chlorine were also incorporated into the film due to contamination of the sputtering

system. In the preparation of actual SRM materials, these would be eliminated

by more careful decontamination.

Trial grids are now being distributed to four cooperating laboratories

for evaluation. In addition to AEM analysis, the films will be analyzed by

laser microprobe mass analyzer and by secondary ion mass spectrometry at NBS.

47
If the material passes the tests for homogeneity and stability, a large

scale sputtering run of 250 grids will be made for preparation of an SRM

candidate in FY82.

Table 2 .X Compositions of Bulk Glass Sputtering Targets in Percent Weight

K-line Standards

Glass L i 2 0 MgO A1 2°3 Si O

2 K2° CaO Mn02 FeO

K411 — 15.00 — 55.00 — 15.00 — 15.00

K1732 5.00 — 10.00 65 . 00 12.00 — 8.00 —

L-l ine Standard

Glass SiO^ Ge0

2 In 2°3 BaO ZnO

K1807 30.00 15.00 5.00 35.00 15.00

" - ,

!' C*sat:

f

MU THIN FILM 83 M

Figure 2. IX Spectrum of glass K-411

48
.20 Stability Testing of SRM's

G. J. Olson, W. P. Iverson and F. E. Brinkman

Chemical Stability and Corrosion Division

Center for Materials Science

This project was undertaken to determine the conditions under which

biodeterioration, either by alteration of the matrix or certified concen- tration of elements, of biologically-fragile SRM's may occur and to make

recommendations for certificate revisions necessary to prevent deterioration

of current and projected SRM's by improper storage or handling. Of the SRM's

examined, oyster tissue (1566), brewers yeast (1569), orchard leaves (1571),

river sediment (1645), wheat flour (1567), and freeze-dried urine (2671, 2672), were sterile. Urban particulate (1648) contained over 20,000 viable microorganisms per gram.

When SRM freeze-dried urine was rehydrated with laboratory distilled

water it became contaminated by the resident microbial flora commonly present in distilled water systems. Little or no microbial growth occurred in

the contaminated urine when stored at 1 °C; however, at room temperature

considerable growth and binding and in some cases volatilization of Hg (the

only certified element in 2671) by the contaminants occurred within three days.

Other sterile SRM's can easily become contaminated by bacteria or fungal

spores present in the air or on utensils used for sample removal. This will

not pose a problem as long as the SRM's remain dry. The a (water activity)

of the SRM's, defined as the ratio of the equilibrium pressure of water in the

SRM to that of pure water at the same temperature (numerically identical to

relative humidity), is the best measurement of availability of water to microorganisms [cf. Table 2 . XQ . Microbes will not grow at a < 0.60, and all the

SRM's examined had aif values less than this value. Therefore, as long as these w

Table 2. XI Incubation time (hours) required for 2 g quantities of

wheat flour SRM to attain different a values when stored

at various relative humidities (30 °Cj.

a , attained

w 60% 72%

Incubation Humidity

86% 93% 100%

0.60 46 3/4 1/2 1/4 1/4

0.72 - 7 1/2 1 3/4 1/2

0.86 - - 7 1/2 2 1 0.93 - - - 31 1/2 14

1.00 - - - - 46

49
SRM's are opened only at relative humidities <60% they should not undergo

biodeterioration, even if they are, or become, contaminated with microorganisms.

However, at higher humidities, the biological SRM's rapidly take up water from

the atmosphere and attain a values permitting microbial growth within hours

or even minutes depending orf the relative humidity they are exposed to. For

example, 2-g quantities of brewers yeast or oyster tissue, which both support

heavy fungal growth at a = 0.70, will reach this water potential after 1/2

and 1 3/4 hours, respectively, at 93% relative humidity. The table shows

incubation times required for wheat flour SRM to reach different a values

when incubated at various relative humidities.

Once microbial growth occurs, certified elements may be accumulated or volatilized by the contaminants. Both events occur with mercury in the urine

SRM. Experiments to detect microbial volatilization of certified elements in

other SRM's have not indicated this occurs. Current experimentation using a coupled gas chromatograph-atomic absorption system should improve our sensitivity and may reveal certified element volatilizations by contaminating fungi

and bacteria growing in certain SRM's.

.21 Eddy Current Standards

A. J. McAlister

Metallurgy Division

Center for Materials Science

The eddy current method is widely used in both the ferrous and non-ferrous

metals industries for nondestructive detection of flaws such as cracks, inclusions, and variations in composition and microstructure in metals and metal

parts via local changes in electrical conductivity. Primary conductivity

standards are needed for reliable execution of this work, but to date, this

need has been supplied by industry itself. The necessary range of conductivity for industrial testing is from 5.85 to 58.5 MSm" 1 (1 to 100% IACS). NBS

is currently acting on the provision of A1 alloy standards in the mid-range of

17 to 35 MSm

-1

(29 to 60% IACS). One hundred sets of four aluminum samples

covering this conductivity range have been supplied to the Electrical Measurement and Standards Division for final calibration.

The properties desired in a primary conductivity standard are long term

stability, durability, and low magnetic susceptibility. (In testing of high

susceptibility steels, normal practice has been to apply a saturating magnetic

field to reduce the differential permeability to a value near that of vacuum.)

Hence, elemental metals and alloys of equilibrium phase composition, upon which

stable nonconducting surface layers can be formed, are desirable. The surface

properties are important not only for durability, but for reproducible lift-off

behavior as well

.

50
The overall aim is the selection of metals and alloys suitable for

primary conductivity reference standards in the 5.85 to 14.6 and 35 to

58.5

MSnf 1 conductivity ranges, and the preparation of specifications

for their preparation and fabrication. Nine candidate materials which

appear suitable on the basis of their reported physical properties and

probable homogeneity and phase and surface stabilities have been identified.

The following metals and alloys will display conductivities within

1% IACS of the stated values:

Material (w/o)

OFHC Cu

1.3 Zn + Cu

2.4 Zn + Cu

21.5 Zn, 2.5 A1 + Cu

7 A1 + Cu

1.5 Si + Cu

3.0 Si + Cu

Commercially pure Ti

8 Al, 1 Mo, 1 V + Ti

Conductivity (% IACS)

100%

85%

72%

23%

17%

12%

7%

3.5%

1 %

For these materials we are investigating the likelihood of attaining the

desired metallurgical and surface properties. Questions concerning these

materials and their preparation -- quality of starting materials, conditions

of melting and solidification, heat and mechanical treatment, possible

adverse affects in cutting, machining, and surface preparation -- are being

addressed by search of the literature and inquiry of industrial practitioners

about their experience and methods and by specific research as necessary.

This project is jointly funded by the Metallurgy Division, Office of

Nondestructive Evaluation and OSRM.

.22 Abrasive Wear Standard

L. K. Ives, F. Matanzo and A. W. Ruff

Metallurgy Division

Center for Materials Science

This project is concerned with improving an abrasive wear test that is

widely used in industry. It has been estimated that perhaps 50% of all wear

can be traced to abrasion. Excavating, mining and agricultural machinery as well as a variety of equipment used in processing and handling abrasive

material must be designed to minimize abrasive wear damage. Accurate data

and appropriate test procedures are necessary both for equipment design

purposes and to assist in the development of more economical and improved

materials. The new ASTM standard dry sand/rubber wheel abrasive wear test

(G65-80) is found to yield results that correlate well with service behavior

when the stresses imposed on abrasive particles are relatively small. Project

staff members have made significant contributions to the development of this

standard test and participated in several interlaboratory test series.

51
The value of the standard dry sand/rubber wheel abrasive wear test

method depends critically on an appropriate calibration procedure. Calibration is best accomplished through the use of reference specimens having

consistent and well established wear behavior. Reference specimens of D-2

tool steel have been developed and are ready for issue. The specimen

material was selected on the basis of our own studies and recommendations

of ASTM G-2 committee members employing the dry sand/rubber wheel test. The

reference specimens will be sold by NBS this fall in sets of 3 for use

in standardizing this test. The possibility of developing additional

reference wear test materials having higher and lower wear resistance

than D-2 tool steel is currently under study.

The project to develop Standard Reference Materials for the dry

sand/rubber wheel test has also included an extensive investigation of

the effects of various machine test parameters and conditions. Abrasive

wear data gathered during the past year concerning test variable effects

have been analyzed and tentative conclusions have been reported in a draft

report. Gaps in the information and questionable data will be the subject

of future tests, including the effect of the lapse time or test order,

moisture content of the sand, and sand flow rate. The machine is now operating with an arm that incorporates a load cell to measure the friction

force. An infrared sensor is also in use to measure the surface temperature

of the rubber rim. Both of these measured test parameters are being

recorded on a dual channel recorder. To increase data recording and analysis

capabilities an eight channel digital recorder is being made ready for

operation.

.23 Particle Shape Characterization

P. J. Blau and E. Whitenton

Metallurgy Division

Center for Materials Science

Quantitative image analysis is being employed in another project to

develop meaningful sand particle shape parameters which relate to their

abrasiveness in wear tests. This project, is focused on characterizing

the abrasive specified for the ASTM Dry Sand/Rubber Wheel Abrasion test.

Abrasive shape has been shown to greatly affect abrasive wear and a more quantitative measure for particle shape could result in improved reproducibility. The goal of this study is to produce a standard method to

conventional image analyzing equipment. During the past year a perimeter

ratio method was seen to discriminate between sands with three different

origins: foundry sand, beach sand, and crushed quartz. Future work

involves exploring the variability of the perimeter ratio among batches

of foundry sand, studying instrumental limitations for measuring perimeter

ratios, and generating sampling requirements to obtain statistically significant values of the shape parameters.

52
.24 Pitting and Crevice Corrosion Standards

A. C. VanOrden and A. C. Fraker

Metallurgy Division

Center for Materials Science

This project has dealt with the production of a standard test method

for pitting and crevice corrosion of surgical implant metals. This ASTM

test method is now at the Society Ballot level. Emphasis of the research

this year has been on specimen design and test configuration and procedures.

The test materials have been 316L stainless steel. The NBS laboratory

acquired 316L stainless steel material from the same supplier as the one for the round robin test material. Eight specimens were made and additional

tests were conducted to check various steps in the procedure. Contribution

to the ASTM F-4 Committee on Medical Material and Devices was made including

participation in two separate rounds of round robin testing. As a result

of the first round robin, the specimen design and test configuration were changed to permit more accurate and valid testing. Preceding the second

round robin tests, the passivation treatment used for implant metals was inserted in the procedure. It is probable that after some minor revision,

this ASTM Standard of Test for Pitting or Crevice Corrosion of Metallic

Surgical Implant Materials will be established. It will be the first cor- rosion standard test for surgical implant metals. Work is being done to

refine the test method and also to produce a Standard Reference Material

for 31 6L stainless steel and plans are being made to provide Standard

Reference Materials for other surgical implant metals.

.25 Crystallite Microsize

C. R. Hubbard and A. Dragoo

Ceramics, Glass and Solid State

Sciences Division

Center for Materials Science

The measurement of mean crystallite size by x-ray powder diffraction

techniques is rapid and nondestructive. Crystallite size measurements are often used to characterize catalysts. However, techniques and analysis

methods vary widely from laboratory to laboratory. The goal of this project

is to provide a set of reference materials of well characterized mean crystallite size between 100 and 1000 Angstroms.

Cubic MgO was chosen as a candidate material because two sets of

diffraction planes can be analyzed by the Warren-Averback method of analysis

of diffraction line profiles to provide mean crystallite size values for two

different crystallographic directions. MgO can be prepared either by precipitation followed by calcination or by collection of the smoke due to

controlled burning of magnesium metal. The latter method is being developed to provide a calibration sample where the crystallites are not agglomerated and simultaneously have well developed crystallographic habit.

53
Initial SEM results have shown some, but not all, of the sufficient smoke

particles for parallel diffraction and SEM calibration is being attempted.

Preparation of the large quantities needed for a SRM of MgO will be by

precipi tation/Calcination methods. The precursor used to date is magnesium

oxalate. Calcination at 60Q°Cfor one hour has yielded a sample with mean crystallite size of about 150 Angstroms. As expected the crystallites are extensively agglomerated. The crystallites have poorly developed habit; some even appear as doughnuts. Other precursors are being tested which

hopefully will lead to crystallites with improved habit.

.26 Glass SRM Research

M. J. Cellarosi

Ceramics, Glass and Solid State

Science Division

Center for Materials Science

a. Glass Dielectric Constant SRM

This task was undertaken by NBS after the recommendations of ASTM

Committee C14.04 on Physical and Mechanical Properties of Glass. Glass is

used extensively in electrical/electronic applications, and an SRM for this

property is designed to support the expanding role and sophistication of glass

in this area.

During the year, interlab measurement activities were continued, several

discrepancies in procedures and calibrations were resolved. This work is

almost completed.

Viscosity SRM 711 samples were used over the frequency range 400 Hz to

10 kHz. Statistical analysis of the data indicate that SRM 711 will qualify

for Dielectric Constant SRM status. A new 3-electrode test cell fixture

developed by NBS to minimize errors due to inductance/capacitance and stray

factors was evaluated and accepted by ASTM for inclusion in standard procedures.

b. Glass Viscosity SRM

In anticipation for renewal of SRM 710 (Soda-lime glass), work to build a new precision viscometer was continued. NBS glass viscosity standards are very important in glass manufacture and research. Initial calibrations of

the torque sensor assembly and rotational mechanism were carried out. Data

indicate the need for modifications to insure better precision/reliability.

c. Glass High Temperature Resistivity SRM

Glass resistivities as a function of temperature in the molten range are important parameters for effective utilization of electric power and for

productivity. NBS leads an ASTM task group on interlab testing, and to develop

standard methods. A second round robin is in progress with SRM 711, which is

already certified for electrical resistivity in the lower temperature ranges.

54
SRM 711 will also be certified for dielectric constant and loss characteristics, so this glass will cover a broad range of electrical properties.

NBS statistical analysis of the first round robin indicated serious measurement discrepancies in the very high temperature range. NBS research is

planned for FY82 to help resolve these problems.

.27 Computer SRM Research

S. B. Geller

Systems Components Division

Center for Computer Systems Engineering

The SRM 3210 calibration system was completed and the production and

issuance of the flexible disk cartridge SRM 3210 was successfully initiated.

This effort included the development of the required documentation for the

associated NBS SRM 3210 certificate.

Two members of the Computer Storage Media Group visited the R and D facility

of the Storage Technology Corporation, Louisville, CO. They were given specialized information relative to the STC Very High Density (VHD) magnetic streaming

media development program. It is anticipated that the Media Group will be

requested by the industry to produce a Very High Density (VHD) magnetic streaming

media SRM as soon as they finalize their approach. These VHD streaming media

will perform as important backups to the state-of-the-art Winchester technology

disk systems.

The minicassette SRM program which has been requested by the U.S. magnetic

media industry (see ANSI draft standard X3B5/81 - 1 4 or later edition) was initiated by the Computer Storage Media Group as a secondary effort while awaiting

VHD media decisions. Four reference minicassett transports and an initial lot

of 100 potential minicassette SRM candidates were purchased. A Field Control

Unit was designed in the media laboratory which controls the minicassette tape

motion in both directions at high or low speeds. Read/write control circuits

and a continuously varying write current control system were also designed.

.28 Thermal Insulation SRM Research

J. G. Hust

Thermophysical Properties Division

Center for Chemical Engineering

a. Fiberboard .

Measurements have been completed and an equation has been developed

describing the experimental data to within the uncertainty of the measurements. The measurements and equation include a temperature range from

100 K to 350 K, gas pressures from high vacuum to atmospheric pressure,

55
various specimen densities, and fill -gas species. The results of this

work are now being correlated with Center for Building Technology results

(at ambient conditions) and a special publication and certificate are

in process.

b. High Temperature Insulation .

Various insulations for high temperature use have been considered

during FY-81. A tentative selection of a commercial supplier has been

made. The insulation selected has promising handling characteristics

(similar to fiberboard) and, based on preliminary screening tests, appears

to be adequately homogeneous. Homogeneity is a more serious problem with

most of the high temperature insulations which have been considered.

56
2.5 SRM Production

This section contains selected highlights for SRM production

projects in FY81

.

. 1 Benchmark Low Alloy Steels —SRM 1 261 a-1 265a

Renewals of the "1200 Series," 1 261 a- 1 265a have been prepared from

the same ingots used for the original series, but from adjacent positions

within the ingots. With the exception of sulfur, little or no change in

elemental composition was observed by comparison analysis utilizing

several analytical techniques. For sulfur, analysis was made by the

"definitive" method of spark-source, mass spectrometry- isotope dilution,

by using the chip forms (SRM's 361-365) and comparing these values to

values measured in chips taken from the disk form (SRM's 1 261 a-1 265a

)

by combustion-infrared. The sulfur values that should be used, whether

for the original series or the renewals are: 1261, 1261a, -0.015%; 1262,

1262a-0. 037%; 1263, 1263a-0.005

? %; 1264, 1264a-0.025%; 1265, 1265a0.0055±0.0003%. This certification was a cooperative project undertaken

as part of the ASTM-NBS Research Associate Program.

.2 Line Pipe Steel --SRM 1269

SRM 1269, Low Alloy Steel (AISI 1526, Mod.) has a composition

chosen for the "line pipe" steel industry. In addition, this SRM is

expected to serve as Supplement No. 2 to the "1200 Series" of Irons

and Steels. Twelve elements are certified, with chemical information

given for 25 additional elements. This certification was a cooperative

project undertaken as part of the ASTM-NBS Research Associate Program.

.3 2 1/4 Cr-1 Mo Low Alloy Steel-SRM 1270

SRM 1270, 2 1/4 Cr-1 Mo Low Alloy Steel (A366 F22) - Planning for

this SRM was coordinated through the Task Group on Temper Embrittlement,

American Petroleum Institute. In addition, this SRM is expected to serve

as Supplement No. 1 to the "1200 Series" of Irons and Steels. Eleven

elements are certified, with chemical information given for 18 additional

elements. This certification was a cooperative project undertaken as part of the ASTM-NBS Research Associate Program.

.4 Cast Steel— SRM Cl 1 73

The Composition of SRM Cl 173 was tailored to extend and complement

existing SRM's 1138a, Cast Steel 1, and 1139a, Cast Steel 2. In so doing, a steel was obtained that exhibited unusual hardness properties.

57
For example, the directionally solidified "as cast" material exhibited

a high hardness for the chill-cast surface (HRC 58 to 60). This is

essentially the same as the water quench hardness *HRC 60); however,

the surface opposite the chill-cast surface was relatively soft and

permitted machining and stamping operations. With proper heat treatment,

a very workable material was obtained (HRC 28). The concentration of

twelve elements are certified in SRM C1173 (C-0.453, Mn-0.174, P-0.031,

S-0.092, Si-1.38, Cu-0.204, Ni-4.04, Cr-2.63, V-0.42, Mo-1.46, Co-0.064,

and Ti-0.037; all in % by weight). In addition, information values are given for six elements (A1 , As, B, Pb, Nb, Zr). This certification was

a cooperative project undertaken as part of the ASTM-NBS Research

Associate Program.

.5 High Alloy Steels— SRM's C1287-C1289

SRM's C1287-C1289, High Alloy Steels, supplement the SRM's C1152-

C1154, Stainless Steels, the "C" preceeding a SRM number denotes that

the specimens were chill cast by a rapid unidirectional solidification

technique. SRM C1287, ACI HK (AISI 310 Mod.), is certified for NI 21.16%,

Cr 23.98%, and 13 other elements, with chemical information on 5 additional

elements. SRM C1288, ACI CN-7M (A-743), is certified for Hi 29.3%, Cr

19.55%, Cu 3.72%, and Mo 2.83%, and 9 other elements with chemical information on 5 additional elements. SRM C1289, ACI CA-6NM (AISI 414 Mod.), is

certified for Ni 4.13%, Cr 12.12%, Mo 0.82%, and 10 other elements, with

chemical information on 5 additional elements. This certification was a cooperative project undertaken as part of the ASTM-NBS Research Associate

Program.

. 6 Hafnium Certified in Zirconium and Zircaloy-4--SRM' s 1234-1239

Three zirconium metal and three Zircaloy-4 metal SRM's have been

certified for their hafnium contents. Hafnium was determined by two

independent analytical methods: isotope dilution-spark source mass spectrometry, and neutron activation. The concentrations range from 46 to

198 qg/g in SRM's 1234-1236, and from 31 to 178 qg/g in SRM's 1237-1239.

The concentrations of 22 additional elements present in each SRM are listed for information only. A number of these may be certified at a later date as a result of collaborative testing.

The SRM's are in the form of solids 32 mm square and 19 mm thick. They

are intended for use primarily in validating experimental data and in

calibrating optical emission and other instrumental methods of analysis.

Because of its high capture cross section for neutrons, hafnium

adversely effects the cost of producing nuclear power. Therefore,

hafnium in reactor-grade, zirconium and Zircaloy must be removed down

to parts-per-mil 1 ion levels. However, the difficulty of determining ppm

concentrations of hafnium has led to disagreements between buyer and

seller of reactor-grade zirconium materials. The reliability of hafnium

58
determinations can be improved by analyzing unknowns relative to these

new SRM's.

.7 15% Austenite in Ferrite--SRM 486

SRM 486 is intended for use in the calibration of x-ray diffraction

equipment which is used in determining the amount of retained austenite

in ferrous materials over the range of 10 to 20 percent. X-ray diffraction procedures recommended for these determinations require accurate

measurements of the integrated intensity for a number of selected peaks.

Each specimen was individually certified by determining the nickel

content by x-ray fluorescence. The calibration of the XRF measurements

was based on the austenite content in 12 specially prepared specimens

as measured with a quantitative microscope (QM). The certified value is

believed accurate to within ±0.5 percent austenite. In special cases

SRM 486 may be used as an x-ray fluorescence standard for determining

the nickel content in nickel -iron or nickel -chromium-iron alloys.

.8 Dye Penetrant Test Block--SRM 1850

NBS recently began issuing this novel SRM, which contains accurately

measured surface "cracks." It is intended for use in checking the sen- sitivity and performance of liquid dye penetrants and dye penetrant crack

detection systems, as well as other systems and devices for surface

defect detection.

The SRM test block (a cross section of a laminate of electrodeposited nickel and copper--the copper being electroetched to form the

"cracks") is about 1/2 cm wide and 2-cm long and is mounted in an epoxyresin disk about 5-cm in diameter and 1-cm thick. Each block contains

four cracks approximately 0.2, 0.5, 1, and 2 ym wide with a separation

distance of about 1.5 mm. Crack depth is several times the width--beyond

the critical depth for showing dye penetrants.

The widths of the cracks at the middle of the block were determined

from measurements made on a metal! ographic microscope using a filar micro

meter eyepiece at a magnification of 1200. The accuracy of these measure

ments was checked by measuring the cracks in several test blocks with a scanning electron microscope (SEM) that had been calibrated for magnification accuracy by SRM 484a. Agreement was within 0.1 ym for the widest

cracks to 0.06 ym for the narrowest.

9. Obsidian Rock and Basalt Rock--SRM's 278 and 688

NBS has issued two new geological reference materials, SRM 278,

Obsidian Rock, and SRM 688, Basalt Rock. The two SRM's are intended

for use in evaluating the accuracy of analytical methods and instruments used to analyze geological materials. Both SRM's are extremely

59
homogeneous and offer the advantage of representing an actual geological

material of the type frequently encountered by the mining and metals

industry in geological research.

SRM 278 and SRM 688 are in the form of a fine powder which was crushed and ground to pass a 200 mesh sieve. SRM 278, Obsidian Rock,

is certified for 18 major and trace constituents, with information given

for another 16 trace constituents. SRM 688, Basalt Rock, is certified

for 14 major and trace constituents, with information values given for

another 17 trace constituents.

.10 Soda-lime-silica Glass for Gradient- furnace Liquidus Temperature-

SRM 773

Standard reference material 773 is a soda-lime-silica glass that is

certified for its liquidus temperature and is for use in checking test

methods and in calibrating equipment specified in the ASTM C829-76 standard

practices. Two methods are included in this ASTM standard, differing in

the form of sample, apparatus, procedure for positioning the sample, and

measurement of temperature gradient in the furnace. Certification of the

materials was carried out at NBS by Mr. Mario Cellarosi.

Method A employs a trough-type platinum container (boat) in which

small glass particles are fused together. Method B employs a perforated

platinum plate on which larger glass particles are individually positioned

one per hole, and are therefore melted separately from each other.

Certified values for the gradient- furnace liquidus temperature (allowing 24 hr. to reach equilibrium) are:

Method Liquidus Temperature

A 988 ± 3 °C

B 991 ± 5 °C

SRM 773 is issued as a set of seven pieces, each one about 2.5-cm

square by 0.6-cm thick. Prior to using the material it must be crushed

by the user in accordance with the ASTM recommended procedure.

. 1 1 Optical Microscope Linewidth Measurement Standard--SRM 475

SRM 475 is a reduced version of an earlier linewidth measurement

standard--SRM 474. The new item is the same type photomask except

rows C and D (which are repetitions of rows A and B) have been omitted

to reduce the cost of calibration and certification at NBS.

60
This reduction benefits the customer in that the price for the new unit

is about one- third lower than the earlier configuration.

SRM 475 is certified for measurement of linewidths from 0.5 to

10 y. It continues to be of special interest to producers of integrated

circuits because it is designed to assist measurement of opaque lines and

clear spaces on integrated circuit photomasks in transmitted illumination.

The accuracy of measured linewidths is the same as the earlier SRM which

is equal to ±0.05 ym or better.

• 1 2 Silicon Resistivity Standard for Eddy Curren t Testers--SRM 1523

SRM 1523 is a resistivity scale reference for the semiconductor

industry. It can be used as a reference for semiconductor resistivity

measurements based on the four-probe method (ASTM Method F-84-73) as well

as those made by the eddy current method (ASTM Method F-673-80). The SRM

consists of two slices of boron-doped silicon. One slice of (100) orientation, Czochralski grown with a nominal resistivity of 0.01 ft,/ cm and the

other slice of (111) orientation, float-zone grown with a nominal

resistivity of 1 ft/ cm. Each slice has been individually measured and

certified for resistivity by NBS.

. 1 3 Polystyre ne (narrow molecu lar weigh t distribution)— SRM 1479

SRM 1479 has been certified to have an average molecular weight of

1,050,000 g/mol , with a systematic error not expected to exceed 1 %. The

material is intended for the calibration and checking of instruments used

in polymer technology for the determination of molecular weight and as a characterized sample for measuring other physical properties of polystyrene.

The new material is the third polystyrene to be certified for molecular

weight. The two earlier offerings are SRM 705 (narrow molecular weight

distribution) with an average molecular weight of 179,000 g/mol and SRM 706

(broad molecular weight distribution) having an average molecular weight

of 258,000 g/mol

.

. 1 4 Butyl Rubber--SRM 1495

SRM 1495, isobutylene-isoprene (butyl) rubber has been certified for

Mooney Viscosity Number according to the procedures described in ASTM

Method D1 646-74 . The material is issued in bales of approximately 34 kg

and is intended for checking the performance of Mooney viscometers when

applied to rubber and rubber-like materials. The (ML 1+8) value for the

SRM is 37.3 at 125 °C and 53.0 at 100 °C, while the (ML 1+4) value is

40.4 at 125 °C and 56.3 at 100 °C.

. 1 5 Potass ium Chloride for Solution Calorimetry— SRM 1655

SRM 1655 is for use in verifying or comparing results obtained by

calorimeters measuring enthalpies of endothermic solution processes.

61
Normally, electrical energy calibrations are performed, and deviation

of measured values from the certified value for the enthalpy of solution

may serve as an indication of systematic errors in the calorimetry. If

proper measuring instruments for electrical energy calibration are not

available, the material may be used as a standard for calibrating a calorimeter. The material is certified with respect to the enthalpy of

the endothermic process of solution in water when carried out under

specified conditions. The energy absorbed during the solution of SRM 1655

in distilled water at 298. 15K to form a solution with molality m = 0.111

mol • kg

_1

is ( 235 . 86±0 . 23 ) J-g" 1.

.16 Benzoic Acid, Acidimetric Standard--SRM 350a

This Standard Reference Material consists of highly purified

benzoic acid and is intended for use in acidimetric standardization.

It has a certified acidimetric assay of 99.9958±0.0Q27 weight percent

and is homogeneous within the bounds of the random error uncertainty

of the measurement process. Stereo and polarized light microscopic

examination of the material, revealed no fluid inclusions or particulate contamination.

.17 TRIS, Basimetric Standard--SRM 723a

This Standard Reference Material consists of highly purified

2-ami no-2- (hydroxymethyl )-l ,3-propanediol [tris-( hydroxymethyl ) aminomethane] (referred to as "TRIS"). It is intended for use in basimetric

standardization, with a basimetric assay of 99.9703±0.0028 weight percent.

No evidence was found for variability between samples from different

segments of the lot beyond that accounted for by the random error of

measurement. Thus, the material is considered to be homogeneous within

the indicated uncertainty limits. Stereo and polarized light microscopic

examination of SRM 723a show no significant particulate contamination.

.18 Human Serum--SRM 909

This SRM, the first certified by NBS for constituents normally

found in human serum, was issued about one year ago. At that time it was certified for calcium, chloride, glucose, lithium, potassium, and

uric acid. Subsequently, additional certification has been provided

for cholesterol and magnesium. In addition, the concentrations of the seven enzymes have been determined in this SRM by a collaborative study

using "best available" methods. The enzymes are: acid phosphatase (low

level), alkaline phosphatase, alanine aminotransferase, creatine kinase,

lactic dehydrogenase, and gamma glutamyl transferase.

.19 4-Nitrophenol--SRM 938

SRM 938, 4-Nitrophenol has been certified for use in calibrating

spectrophotometers for clinical analyses in which 4-nitrophenol is the

chromogenic compound that is formed. The certified apparent specific

62
absorbance of the material at 401 nm and 23.5 °C is 131.48 ± 0.33 L*g ^

* cm for solutions containing between 4 and 5 mgM." 1 in aqueous 0.01C mol*!/ 1 sodium hydroxide. Analysis of the material indicates 99.75% purity and no

2- or 3-nitrophenol at a detection limit of 1 part per 1000.

. 20 Sodium Pyruvate- -SRM 910

This Standard Reference Material (SRM) is certified as a chemical of

known purity, especially for use in clinical chemistry. It is intended

primarily for use in the calibration and standardization of procedures

for pyruvate, lactic dehydrogenase, and glutamic-pyruvic transaminase

determinations in clinical analyses, and for critical evaluation of the

routine working or secondary reference materials used in these procedures.

The material is certified as being sodium pyruvate, 98.7%, and parapyruvate, 0.9%.

. 2 1 Oxygen in Nitrogen, 21 Mole Percent— SRM 2659

SRM 2659 supplements the two SRM's previously issued for 2 and 10 mole

percent oxygen in nitrogen. They are intended for use in the calibration

of instruments used for combustion control and respiratory gas analysis.

The nominal concentrations of oxygen in the three SRM's are:

SRM 2657 2 mole % Oxygen

SRM 2658 10 mole % Oxygen

SRM 2659 21 mole % Oxygen

Each cylinder is individually analyzed. The uncertainty in the

certified oxygen concentration at the 95% confidence level does not exceed

1.0% relative. These SRM's were developed primarily for use in U.S.

Environmental Protection Agency Method 20 which requires continuous

source emission monitors for measurements of 0 2 and NO . One of the

procedures for determining the concentrations of 0 2 anci NO in the calibration gases uses SRM's as specified in EPA Protocol No. T (Traceability

Protocol for Establishing True Concentrations of Gases Used for Calibration and Audits of Continuous Source Emission Monitors).

.22 Sulfur Dioxide i n Nitrogen for Stack Gas Analysis

In March 1981, several additional concentrations were made available

in series of SRM’s used in calibrating stack gas analysis The complete

63
range now is as follows:

SRM

Nominal

Concentration

ppm

1693

1694

1661a

1662a.

1 663a

1664

1696

50

100

500

1000

1500

2500

3500

.23 Methane and Propane in Air— SRM 1660a

This new standard reference material is intended for use in calibrating

instruments used to differentiate the methane and nonmethane fractions of

hydrocarbons in the atmosphere. Its nominal composition is 4 ppm methane

and 1 ppm propane, in air, where each cylinder is analyzed and an individual

certificate is issued. The SRM is intended as a primary standard of ambient

air quality to which the concentrations of daily working standards may be

related.

. 24 Generator Columns for Polynuclear Aromatic Hydrocarbo ns--S RM 1644

This SRM was developed to generate known, accurate concentrations of

anthracene, benzo(a)anthracene, and benzo(a)pyrene in water. Accurate

concentrations of these low-solubility compounds, which range from 1 to

50 yg/kg (ppb) are difficult to achieve by other techniques. The certificate for this SRM lists the certified concentrations that are obtained

when the generator columns are used as directed. The SRM consists of

three stainless steel tubes, each packed with sea sand that is coated with

one of the three compounds. In operation, a saturated solution results

when water is flowed through the tube at a flow rate between 0.1 and 5 mL/min.

The aqueous concentrations were determined by methods using high perfor- mance liquid chromatography and fluorescence. These two independent

analytical methods gave concordant results.

Many compounds classified as polynuclear aromatic hydrocarbons (PAHs) are known to be carcinogenic or cocarcinogenic. Their determination in

water samples is necessary to assess the environmental hazards associated

with increased use of coal and the development of synthetic fuels. Anthracene, benzo(a)anthracene, and benzo(a)pyrene were selected to represent

PAHs, because they have a three, four, and five-condensed ring structure,

respecti vely , and are EPA Priority Pollutants.

64
.25 Stabilized Wine--SRM 1590

SRM 1590 is intended primarily for evaluating the accuracy of ethanol

determinations in wine and calibrating the instruments used in these

determinations. Disputes over the ethanol content of wines may be

attributable to discrepant analytical results among laboratories. Because

of the difficulty of validating these results, the American Society of

Enologists suggested the development of this wine SRM to validate

analytical data.

In addition to the certified concentration of ethanol, the certificate

of analysis provides information on the concentrations of copper, iron,

potassium, sodium, volatile acidity, and total acidity. These values,

which are not certified, were obtained as a result of a collaborative study

conducted by the American Society of Enologists. Samples were analyzed at

NBS by two independent analytical methods: gas chromatography and titration

of the ethanol after separation.

. 26 Reflection Step Tablet—SRM 2061

Standard reference material 2061 is a calibrated reflection step

tablet having 12 steps that cover the optical density range from 0 to 2 on gray scale paper from white to black. It is intended primarily for

use in photographic applications requiring color balance or separation.

The new SRM 2061 tablet is calibrated by the NBS Radiometric Physics

Division using methods that conform to conditions specified for American

National Standard Annular 45°; 0° Absolute Visual Reflection Density.

Type 3000 K, in ANSI PH2. 17-1 977.

The step tablet is 35 by 254 mm in dimension and each step is 20 by

35 mm. Measurements were made within a circle 4.76 mm in diameter at the

center of each step. The certified values apply only to these areas. The

densities listed for these areas are the averages of three independent

measurements. The total uncertainty is 0.02 or 2%, whichever is greater.

.27 Computer Amplitude Reference, Disk Cartridge— SRM 3210

SRM 3210 is a reference magnetic flexible disk cartridge recording

and reproducing systems.

At the request of Government procurement agencies, media testing

laboratories, producers of computer magnetic media and producers of

media handling and associated equipment, the National Bureau of Standards

has developed and will supply unrecorded Secondary Standard Flexible Disk

Cartridges (Computer Amplitude Reference) through the NBS Office of Standard

Reference Materials.

65
The new material consists of a 200 mm(8 inch) unrecorded magnetic

flexible disk cartridge whose dimensions conform to the American National

Standards Institute (ANSI) Standards, the International Organization for

Standardization (ISO) Standards, and the European Computer Manufacturers

Association (ECMA) Standards.

Each flexible disk cartridge is calibrated in terms of the 100 percent

signal levels established by the NBS Master Standard Flexible Disk

Cartridge (Computer Amplitude Reference). These signal level calibrations are made at the test recording frequencies of 250,000 flux transitions

per second on track 00 and at 500,000 flux transitions per second on track 76.

.28 Second Surface Aluminum Mirrors for Specular Reflectance--SRM' s 2023-2024

SRM’s 2023 and 2024 are intended for use in calibrating the photometric

scale of specular reflectometers. SRM 2023 is 5.1 x 5.1 cm in size and

SRM 2024 is 2.5 x 10.1 cm in size. The aluminum mirror is vacuum deposited

on the surface of a 2-mm thick fused-quartz plate. This mirror is protected

by a second fused-quartz plate attached to the first plate with epoxy cement.

The specular reflectance of the mirror was measured at 50-nm intervals

from 250 nm to 900 nm, at 100-nm intervals from 900 nm to 1300 nm; and at

250-nm intervals from 1500 nm to 2500 nm. In addition to these wavelengths,

the reflectance was also measured at the laser wavelengths 632.8 nm and

1060 nm. The research and development of the SRM was supported by the DoE

Solar Thermal Program through the Solar Energy Research Institute,

. 29 Plutonium-244 Spike Assay and Isotopic Standard--SRM 996

This SRM is certified for concentration and isotopic composition for

use as a spike for plutonium determination by isotope dilution mass spectrometry (IDMS). It consists of a plutonium residue contained in a Teflon bottle. The residue was formed by evaporating an aliquant of a plutonium nitrate solution (M mg Pu) to dryness at ^90 °C. SRM 996 is

supplied with recommended procedures for reconstitution and use. It was prepared and certified by three national laboratories : the National

Bureau of Standards, the New Brunswick Laboratory of the Department of

Energy, Argonne, Illinois, and the University of California Los Alamos

Scientific Laboratory, Los Alamos, New Mexico.

. 30 Envi ronmental Radioactivity, "Rocky Flats Soil Number 1" —SRM 4353

This Standard Reference Material has been developed in cooperation

with member laboratories of the International Committee for Radionuclide

Metrology and consists of approximately 90 grams of air-dried, pulverized

soil in a polyethylene bottle. The sample was collected from Rocky Flats, CO.

66
It is intended for use in tests of measurements of environmental radioactivity

contained in matrices similar to the sample.

.31 Hydrogen-3 Radioactivity Standard—SRM 4361

This new radioactivity standard is tritiated water in a flame-sealed

glass bottle. It has a radioactivity concentration of 1.31 s -1

g _1

and a half-life of 12.43 years. The instrument used for calibration of each

hydrogen-3 source was a 4tt3 internal gas proportional counter.

. 32 Low-energy Photon Standard--SRM 4266

This new radionuclide SRM for calibrating low-energy photon counting

systems is vanadium-49. It is a point source of dried vanadium-49, as the

chloride, deposited between polyester film and tape, and held in an aluminum

annulus. The radionuclide has a halflife of 302.2 days and is for K x-ray

emission rate per steradian as determined with the NBS low-geometry NaCl

x-ray detector system.

. 33 Mixed-Radionuclide Point-Source Standard Efficiency Calibration of

Germanium-Spectrometer Systems--SRM 4276

This standard is intended for use in measuring the full -energy-peak

efficiencies of spectrometer systems for x and gamma rays from 27 to

1274 keV, provided that the responses to radiations approximately 5 keV

apart can be resolved. Emission rates are specified at 18 energies for

photon radiations from a mixture of antimony-1 25-tel lurium-1 25m, europium-154,

and europium-155. Uncertainties are estimated and combined at a level cor- responding to a standard deviation of the mean, with the intent that the user can propagate this uncertainty along with other uncertainties in the

spectrometer calibration.

67
2 . 6 Data Base Management System

The new Texas Instruments 990/12 minicomputer system was made fully

operational during FY81 . Also installed during the year was a new tape

drive and 100 M Bytes of hard disk memory. The development of the new COBOL programs for use in processing of SRM orders and inventory control

is progressing. The new system is expected to be implemented on a trial

basis (in parallel with the old system) in early 1982. The pending implementation of the new system will result in better service to SRM customers

through more efficient processing of orders, more effective handling of

backorders, quicker and more complete response to customer inquiries, and

improved billing procedures.

2.7 ASTM Research Associate Programs

.1 Metal SRM's

For six years the ASTM has supported a Research Associate Program

at NBS to assist in the certification of metal and metal -related SRM's.

The project is under the sponsorship of ASTM Committees E-2 on Emission

Spectroscopy, E-3 on Chemical Analysis of Metals and E-16 on Sampling and

Analysis of Metal Bearing Ores and Related Materials. Coordinating Committee

S-17, is chaired by Luther Ikenberry of Armco Steel Company -- Mr. James Shultz

and Mr. Rosemond K. Bell are the two Research Associates assigned to this

program by ASTM. Mr. Robert E. Michael is of OSRM is the NBS liaison. During

the last six years, 100 certifications have been completed and a similar

number of projects are underway to provide additional SRM's.

The approach in the metals RAP continues to have NBS emphasize

development and production of new metal SRM's involving more challenging

measurement problems. The burden for certification of renewals is placed

primarily on the Research Associates and cooperating laboratories. NBS

helps by providing oversight to each project and homogeneity testing. NBS

also stands ready to resolve discrepant cooperator data through direct

analysis. Over 225 laboratories throughout the U.S. (and eight foreign

countries) have participated in the metals RAP.

.2 Glass SRM's

In the fall of 1980, ASTM and NBS concluded an agreement whereby ASTM

would sponsor a research associate at the Bureau to develop several new glass SRM's in support of the industry. The new Research Associate is

Dr. August C. Seifert, former research director at Owens-Corning Fiberglass

Corporation, and his liaison at NBS is Mr. Mario J. Cellarosi.

68
Within ASTM the program is under the guidance of Committee C-14.91,

whose chairman is Mr. Henry E. Hagy, of Corning Glass Works. Committee

C-14.91 is a special committee established under Committee C-14 on Glass

and Glass Products. Mr. Hagy has worked with representatives of many glass

companies to develop, by means of ASTM ballot, a priority list of industrial

needs for glass reference materials. The top five priorities on the fourteen

item list are: 1) thermal expansion glass; 2) ferrous- to-ferric ratio in

borosilicate glass; 3) soft borosilicate glass composition; 4) electrical

resistivity glass; and feldspathic ( 3%- 1 0% A1 2 0 3 ) sand.

Work is beginning on the development of SRM's on the priority list.

Prior to initiation of the research associate program, ASTM Subcommittee

C-14. 04, also under the chairmanship of Mr. Hagy, worked together with nine

glass companies and the National Bureau of Standards to produce the new glass SRM for liquidus temperature.

.3 SRM's for Particle Metrology

In Septemoer 1981, OSRM reached agreement with ASTM to establish a third Research Associate Program in the area of SRM's for particle metrology.

A special coordinating committee, S-21 on SRM's for Particle Metrology, has

been established by ASTM under the chairmanship of David W. Johnson, Jr. of

Bell Laboratories. S-21 represents the interests of over 15 different ASTM

parent committees that have an interest in fine particle measurements.

Mr. Russell C. Obbink, formerly with Alcoa Laboratories, has been selected

as the new Research Associate. Mr. R. Keith Kirby of OSRM is MBS liaison

for the program.

2.8 AIF Research Associate Program

During FY81 , the Research Associate Program sponsored by the Atomic

Industrial Forum (AIF) for Radiopharmaceutical SRM's was renewed.

This project has already resulted in the certification of over 20

different short-lived radionuclide SRM's for use in measurement quality

assurance during the manufacturing of radio pharmaceuticals. A cost recovery

agreement has been implemented for this project.

Mr. Daniel B. Golas is the Research Associate assigned to the project

by AIF and Dr. Dale D. Hoppes, Nuclear Radiation Division is serving as NBS liaison.

2.9 International SRM Activities

. 1 International Organization for Standardization

OSRM continues to maintain an important role in international SRM

activities. Within the International Organization for Standardization

69
(ISO), OSRM has been a major contributor to the work of the Council Committee

on Reference Materials (REMCO), since its inception. During FY81, George A.

Uriano was selected by ISO Council to serve as Chairman of REMCO for three

years. Uriano chaired the 7th Meeting of REMCO held in Paris, France during

September 22-24, 1981. At that meeting, the revised International Directory

of Certified Reference Materials, prepared by OSRM Consultant, J. Paul Cali, was accepted for publication as an official ISO Directory. Dr. Keith R. Eberhardt, Statistical Engineering Division, is currently a member of a REMCO taskgroup preparing a statistical guide for the preparation and use

of reference material certificates.

.2 International Union of Pure and Applied Chemistry

During FY81 , George A. Uriano was elected to Titular Member, vicechairman, and secretary of Commission 1.4, on “Physicochemical Reference

Materials and Standards," of the International Union of Pure and Applied

Chemistry (IUPAC). Among the activities of the Commission are: (1) the

preparation of an annotated bibliography on accuracy in measurement,

(2) preparation of monographs describing reference methods for the

realization of physicochemical quantities, and (3) publication of recom- mendations for reference materials used in physicochemical measurements.

.3 U.S. -Egypt Cooperative Program

Stanley D. Rasberry was part of an NBS team sent to Egypt during

September 10-20, 1981 to make arrangements for a cooperative NBS-Egyptian

applied science and technology research program sponsored by the U.S. Agency

for International Development (AID). The maintenance and distribution of

NBS SRM's by the National Institute for Standards of Egypt was discussed.

Mr. Rasberry also consulted with the Egyptian Organization for Standardization

and Quality Control with regard to the aquisition, installation and operation

of a wavelength dispersive, x-ray fluorescence spectrometer intended for

analysis of a wide range of materials, including metals, cement, glass,

petroleum and gasoline.

.4 Royal Society of Chemistry Meeting

Stanley D. Rasberry was invited to present a paper describing NBS SRM

activities before a special meeting on reference materials organized by the

Royal Society of Chemistry in London during February 1981. Invited papers

were also presented by nine other reference material producers in the U.K.

and Europe. Mr. Rasberry met with Dr. Harold Egan, Government Chemist of

the United Kingdom and Dr. Peter Ridsdale, Bureau of Analysed Samples Ltd.

to review the activities of their organizations of interest to NBS.

70
.5 DoC Trade Exhibits in Ecuador and Columbia

In March 1981, Robert Alvarez participated in a U.S. Instrument and

Related Equipment Catalog Exhibition in Ecuador and Colombia, as an industry technical representative. Sponsored by the International Trade

Administration of the Department of Commerce, the exhibition was designed

to test market interest, develop trade leads, and locate agents and

distributors for the exhibitors' products and services. Alvarez responded

to technical inquiries and discussed the use of SRM's in quality control to

calibrate instrumentation and validate measurements.

.6 Chemical Institute of Canada Meeting

In June 1981, Robert Alvarez presented a paper entitled, "Recent

Developments in NBS Chemical Composition Standard Reference Materials for

Quality Control Application," at a Chemical Institute of Canada meeting in

Halifax, Canada. He met with National Research Council of Canada scientists

to discuss their progress in the development of a sea water certified

reference material. This material is to be issued in 1982.

J Fourth European Conference on Analytical Chemistry

At the Fourth European Conference on Analytical Chemistry in Espoo

(Helsinki) Finland, Robert Alvarez gave a talk on "New NBS Certified

Reference Materials for Validating Clinical and Health Related Measurements. The talk highlighted the two NBS human serum SRM's - one certified for concentrations of anti epilepsy drugs; the other for constituents,

such as glucose and cholesterol, commonly found in serum and measured for

diagnostic purposes.

.8 International Conference on Heavy Metals in the Environment

Thomas E. Gills attended the International Conference on Heavy Metals

in the Environment held in Amsterdam in September 1981. This was the third

conference in a series concerned with health effects, pathways and cycling,

waste control, metal speciation and analytical techniques pertaining to

heavy metals in the environment.

.9 U.S. -Italian Cooperative Research on Reference Materials

Thomas E. Gills presented a paper at the University of Pavia (Italy)

entitled, "The Use of Nuclear Methods in Certifying Standard Reference

Materials." He also negotiated a final agreement on specific research

initiatives under the joint NBS-Italian cooperative agreement for the

chemical characterization of reference materials.

71
.10 NBS - WHO Collaboration

NBS continues as a Collaborating Center of the World Health Organization

in the area of clinical chemistry. The OSRM is responsible for reviewing WHO

technical proposals.

. 1 1 Bilateral Activities

Bilateral SRM activities continue to be of interest and use to OSRM.

During FY81 , NBS and the French National Bureau of Metrology (BNM) completed

an intercomparison of measurements on four different sets of gas SRM's for

use in air pollution monitoring. Agreement between the two countries was excellent. The joint NBS/BNM project for certification of octane rating

SRM's is also nearing completion. Negotiations have begun with the National

Physical Laboratory (NPL) of the United Kingdom to initiate cooperative SRM

certification projects.

During FY81 , Mrs. Pan Xiurong, State Bureau of Metrology, Peoples

Republic of China was a guest worker in OSRM for one month. She is one of

the responsible Chinese officials who will be starting a new Chinese Institute

for Reference Materials in Beijing.

72
3. OSRM STAFF PUBLICATIONS, INFORMATION TRANSFER AND COMMITTEE ACTIVITIES

3 . 1 Publications, Journal Articles, and Written Reports by OSRM Staff in FY81

--Alvarez, R., "Report on Reference Materials and Standard Solutions,"

J. Assoc. Off. Anal. Chem . (Vol. 64, No. 2, 1981).

--Kirby, R. K. , "Recent Activities of the National Bureau of Standards and

the American Society for Testing and Materials in Developing Particulate

Standard Reference Materials," Proceedings of the Fine Particle Society

Meeting - 1980, University of Maryland, Sept. 18, 1980.

--Kirby, R. K. , "The NBS Program for Standard Reference Materials,"

Proceedings of the N8S-EPA Asbestos Standards Workshop, NBS, Gaithersburg, MD,

Oct. 1, 1980.

--Michael is, R. E. (coauthored with Shultz, J. I.), "Progress Report-NBS ASTM

Research Associate Program," distributed March 30, 1981, to ASTM Coordinating

Committee S-17 on Reference Materials.

--Michael is, R. E. (with other OSRM staff members), "NBS Standard Reference

Materials, 1980 Status Report, March 1, 1981, distributed at the Pittsburgh

Conference and to ASTM Committees E-02, E-03, E-16, and S-17. —Michaelis, R. E., "Report on the NBS-SRM Program and Other Sources for RM's,"

31st Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy,

Atlantic City, NJ, March 9-13, 1981 (published in minutes of meeting by ASTM

Committee E-2 on Emission Spectroscopy).

--Michaelis, R. E., "Summary Report on NBS SRM Program," Meeting of ASTM Committee E-2 on Emission Spectroscopy, NBS, Sept. 28, Oct. 1, 1981. (Published

in minutes of ASTM Committee E-2, Subcommittee IV on Standard Reference

Materials, Sampling, Electrodes, and other Spectrochemical Materials).

--Rasberry, S. D., ed. , "Reference Materials,"

(10)

, pp. 63-64 (1980).

--Rasberry, S. D. , ed., "Reference Materials,"

(11)

, p. 146 (1980).

-••Rasberry, S. D., ed., "Reference Materials,"

(12)

, p. 84 (1980).

--Rasberry, S. D., ed. , "Reference Materials,"

(1)

, pp. 134-135 (1981).

-•-Rasberry, S. D., ed., "Reference Materials,"

(2) pp. 167-168 (1981).

American Laboratory 1

2

American Laboratory 1

American Laboratory 12

American Laboratory 1

3

American Laboratory 1

3

73
-Rasberry, S. D., ed. s (4) pp. 89-95 (1981).

-Rasberry, S. D., ed. s (6) pp. 79-82 (1981).

-Rasberry , S. D. , ed.

,

(7) p. 83 (1981).

-Rasberry, S. D. , ed.,

(8) p. 104 (1981).

-Rasberry , S. D. , ed. s (9) p. 136-138 (1981)

"Reference Materials,"

"Reference Materials,"

"Reference Materials,"

"Reference Materials,"

"Reference Materials,"

American Laboratory 13

American Laboratory 13

American Laboratory 13

American Laboratory 13

American Laboratory 1

3

-Rasberry, S. D., ed. , "Current Work and Future Plans in Reference Materials,"

extended summary in The Analyst - England (in press).

-Uriano, G. A. and Rasberry, S. D. ,

,[ C1 inical Laboratory Use of SRM 909 - Human Serum," Pathologist (in press).

-Uriano, G. A., "The Certified Reference Materials Program of the United

States National Bureau of Standards," pp. 7 - 24, Proceedings of the

International Symposium on the Production and Use of Reference Materials,

Nov. 13-16, 1979, published by Bundesanstal t fur Material priifung (Berlin),

B. F. Schmitt, editor (1980).

-Uriano, G. A., "Management Considerations for Planning and Operation of a Coal Reference Materials Sample Bank," Proceedings of the Coal Sample Bank

Workshop, March 27-28, 1981, Atlanta, GA (in press).

-Uriano, G. A. (Rasberry, S. D. , editor), "Reference Materials," American

Laboratory 13 (1) p. 134 (1981).

-Uriano, G. A. and Rasberry, S. D. , ed., "Annual Report 1981-Office of

Standard Reference Materials (1981).

-Zeisler, R., Greenberg, R. R., Gills, T. E., and Lindstrom, R. M.

,

"Nuclear Activation Techniques Used for the Determination of 18 Trace

Elements in New Standard Reference Water," Proceedings of the American

Chemical Society.. Division of Environmental Chemistry, Houston, TX,

March 23-28, 1980.

74
3.2 Technical Lectures/Tal ks Given by OSRM Personnel

—Alvarez, R., "The Role of Standard Reference Materials in a Reliable

Measurement System," VII Annual Meeting of the Federation of Analytical

Chemistry and Spectroscopy Societies, Philadelphia, PA, Sept. 28 - Oct. 3, 1980.

--Alvarez, R., "Standard Reference Materials for the Analysis of Food and

Plant Tissue," VII Annual Meeting of the Federation of Analytical Chemistry

and Spectroscopy Societies, Philadelphia, PA, Sept. 28 - Oct. 3, 1980.

--Alvarez, R., "New NBS Standard Reference Materials for AOAC Use,"

Association of Official Analytical Chemists, Washington, D.C., Oct. 20, 1980.

--Alvarez, R., "General Referee's Report on Reference Materials and Standard

Solutions," 94th Annual Meeting, Association of Official Analytical Chemists,

Washington, D.C., Oct. 20, 1980.

--Alvarez, R., "National Bureau of Standards Standard Reference Materials for

Accurate Analysis of Materials," Science and Technology Enrichment Program,

Montgomery County, MD (two talks):

E. B. Wood, Jr. High School, Rockville, MD, Dec. 9, 1980.

E. B. Lee, Jr. High School, Silver Spring, MD, Feb. 2, 1981.

--Alvarez, R., "New Developments in NBS Standard Reference Materials - 75 Years Later," 15th Middle Atlantic Regional Meeting, Amer. Chem. Soc.,

Washington, D.C., Jan. 7, 1981.

--Alvarez, R., "NBS Standard Reference Materials for Validating Nutrient

Element Determinations in Foods," 15th Middle Atlantic Regional Meeting,

Amer. Chem. Soc., Washington, D.C., Jan. 8, 1981.

--Alvarez, R., "National Bureau of Standards Standard Reference Materials for

Industrial Quality Control (in Spanish)," Catalog Exhibition for U.S.

Scientific Instruments and Related Equipment, U.S. Embassy, Quito, Ecuador,

March 12-13, 1981 (talk given each day).

--Alvarez, R., "Recent Developments in NBS Chemical Composition Standard

Reference Materials for Quality Control Application," The 64th

Canadian Chemical Conference and Exhibition, The Chemical Institute of

Canada, Halifax, N.S., Canada, June 1, 1981.

--Alvarez, R., "New NBS Certified Reference Materials for Validating Clinical

and Health-Related Measurements," Fourth European Conference on Analytical

Chemistry, Euroanalysis-IV, Helsinki, Finland, Aug. 24, 1981.

--Gills, T. E., "Status of NBS Nuclear Standards for FY81," Meeting of ASTM

Committee on Nuclear Fuel Cycle, Reno, Nevada, Sept. 1981.

75
--Gi 1 1

s

3 T. E., invited talk "The Use of Nuclear Methods in Certifying

Standard Reference Materials," University of Pavia, Pavia, Italy,

Sept. 22, 1981.

--Kirby, R. K. , "Standard Reference Materials and Quality Assurance of

Chemical Analysis," 1981 Measurement Science Conference, Anaheim, CA,

Jan. 30, 1981.

--Kirby, R. K. , "SRM/Transfer Standards," MBS Measurement Seminar on Thermal

Resistance of Insulating Materials, NBS, Gaithersburg, MD, July 16, 1981.

--Kirby, R. K. , "Standard Reference Materials," 23rd Rocky Mountain Conference,

Denver, CO, Aug. 4, 1981.

--Michael is, R. E., "Testing and Characterization of SRM's," Inorganic

Analytical Research Division Seminar, NBS, Oct. 16, 1981.

--Michaelis, R. E., "Report on the NBS-SRM Program and Other Sources for RM's,"

31st Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy,

Atlantic City, NJ, March 9-13, 1981.

--Michaelis, R. E., "Standard Reference Materials," representatives of National

Research Laboratory of Metrology, Tokyo, Japan, at NBS, April 26, 27, 1981.

--Michaelis, R. E., "Summary Report on NBS SRM Program," Meeting of ASTM

Committee E-2 on Emission Spectroscopy, NBS, Sept. 28, Oct. 1, 1981.

--Rasberry, S. D., invited lecture "NBS: Current Work and Future Plans in

Reference Materials, Royal Society of Chemistry, London, England, Feb. 4, 1981.

--Rasberry, S. D. , "Standard Reference Materials: Present and Future,"

Spectroscopy Society of Pittsburgh, Duquesne University, Pittsburgh, PA,

February 19, 1981

.

--Rasberry, S. D., "X-ray Fluorescence Spectrometry - A Technique for Rapid

Analysis," Egyptian Organization for Standardization and Quality Control,

Cairo, Egypt, Sept. 14, 1981.

--Rasberry, S. D., "Standard Reference Materials in Support of Measurement

Quality," National Institute for Standards, Cairo, Egypt, Sept. 15, 1981.

--Rasberry, S. D., "The Future of the SRM Program," ASTM Committee E-2 Meeting

held at NBS Sept. 28-0ct. 1, 1981.

--Uriano, G. A., "The NBS Standard Reference Materials Program," Seminar,

Dept, of Energy, Div. of Fossil Fuel Research, Germantown, MD, Jan. 21, 1981.

--Uriano, G. A., invited talk "Management Considerations for Planning and

Operation of a Coal Reference Materials Sample Bank," DoE-GRI Coal Sample

Bank Workshop, Atlanta, GA, March 27, 1981.

76
--Uriano, G. A., "The NBS Standard Reference Materials Program," U.S. House

of Representatives, Science and Technology Committee, National Bureau of

Standards, June 8, 1981.

--Uriano, G. A., "A New International Directory of Certified Reference

Material Producers," Council Committee on Reference Materials, International

Organization for Standardization, Paris, France, Sept. 22, 1981.

3.3 Standards Committee and Other Standards Activities

Alvarez, R. - Association for Official Analytical Chemists (AOAC)

AOAC Subcommittee on Reference Materials and Solutions

AOAC General Referee for Reference Materials

American Society for Testing & Materials (ASTM)

E-02 - Emission Spectroscopy

E-02.05 - Copper, Nickel, and High Temperature Alloys

Gills, T. E. - American Society for Testing and Materials (ASTM)

C-26 on Nuclear Fuel Cycle

C-26.05 Test Methods

C-26. 01 Editorial and Terminology

Kirby, R. K. - American Society for Testing and Materials (ASTM)

E-29 on Particle Size Measurement

E-37 on Thermal Measurement

E-37.02 on Standard Reference Materials

E-37. 05 on Thermal Properties

S-21 Coordinating Committee for Standard Reference

Materials for Particle Metrology

C-14 on Glass and Glass Products

C-14.91 on Standard Reference Materials

Michaelis, R. E. - American Society for Testing and Materials (ASTM)

S-17 SRM's for Metals, Metal Bearing Ores, and

Related Materials

E-02 on Emission Spectroscopy

E-02 (Executive Committee)

E-02. 02 on Statistics, Calibration, Standardization,

and Interlaboratory Testing

E-02. 04 on Standard Reference Materials, Sampling,

Electrodes, and other Spectrochemical Materials

E-02.05 on Copper, Nickel; and High Temperature Alloys

E-02. 06 on Lead, Zinc, Tin, and Precious Metals

E-02. 07 on Aluminum, Magnesium and Their Alloys

E-02. 08 on Refractory Metals, Beryllium and Their Alloys

E-02. 09 on Ferrous Alloys

E-02. 10 on Miscellaneous Non-Metal! ic Materials

77
Rasberry, S. D. - American Society for Testing and Materials (ASTM)

E-02 on Emission Spectroscopy

C-14.91 on SRM's for the Glass Industry

U.S. Pharmacopeia (Delegate)

Agency for International Development (Standards

Assistance to Egypt)

Seward* R. W. - American Society for Testing and Materials (ASTM)

E- 1 3 on Molecular Spectroscopy

E-13.01 on UV and Visible Spectroscopy

Uriano, G. A. - American Society for Testing and Materials (ASTM)

E-02 on Emmission Spectroscopy

U.S. Delegate to ISO Council Committee on Reference

Materials (REMCO)

Chairman of ISO/REMCO

Consultant to Standards Committee, American Association

for Clinical Chemistry

Vice Chairman, Secretary and Titular Member of Commission 1.4 on Physico-chemical Reference Materials and Standards,

International Union of Pure and Applied Chemistry

Consultants' Panel on Analytical Quality Control, International

Atomic Energy Agency, United Nations

3 . 4 NBS Special Publication 260 Series

The OSRM is responsible for the publication and dissemination of

information on all phases of the preparation, measurement, certification,

and utilization of SRM's. One of the major mechanisms for carrying out

this responsibility is the publication and distribution of the NBS Special

Publication 260 Series on SRM's. Since 1964 over 70 SP 260 reports--

authored primarily by technical division staff--have been published, describing the preparation and use of a variety of SRM's and associated

measurement methods. In FY81 , the following SP 260 's were published by OSRM:

--Marinenko, R. B., Biancaniel lo, F., Boyer, P. A., Ruff, A. W.,

DeRobertis, L., Standard Reference Materials: Preparation and

Characterization of an Iron-Chromium-Nickel Alloy for Microanalysis,

NBS Spec. Publ . 260-70 (May 1981) $2.50.

--Seward, R. W. and Mavrodineanu, R., Standard Reference Materials:

Summary of the Clinical Laboratory Standards Issued by the National

Bureau of Standards, NBS Spec. Publ. 260-71 (in press).

--Reeder, 0. J., Coxon, B., Enagonio, D., Christensen, R. G., Schaffer, R.,

Howell, B. F., Paule, R. C., Mandel , J., Standard Reference Materials:

SRM 900, Antiepilepsy Drug Level Assay Standard, NBS Spec. Publ. 360-72

(June 1981) $4.25.

78
--Interrante, C. G. and Hicho, G. E., Standard Reference Materials: A

Standard Reference Material Containing Nominally Fifteen Percent Austenite

(SRM 486), NBS Spec. Pub! . 260-73 (in press).

NOTE : To order these publications, send order with remittance (add 25 percent

for other than U.S. mailing) to Superintendent of Documents, U-S. Government

Printing Office, Washington, D.C. 20402.

For further information, contact the Office of Standard Reference Materials,

Room B-311, Chemistry Building, National Bureau of Standards, Washington, D.C.

20234. Telephone (301) 921-2045.

3 • 5 FY81 Technical Exhibits With Staffed SRM Displays

Pittsburgh Conference on Analytical Chemistry and Applied

Spectroscopy, March 9-13, 1981, Atlantic City, NJ.

Western Technology Conference (WESTEC), Los Angeles, CA,

March 23-27, 1981.

American Chemical Society Meeting, Atlanta, GA, March 29 - April 4, 1981.

Air Pollution Control Association Meeting, Philadelphia, PA,

June 23-25, 1981.

American Association for Clinical Chemistry Annual Meeting,

Kansas City, MO, July 19-25, 1981.

Federation of Analytical Chemistry and Applied Spectroscopy

Societies, Philadelphia, PA, Sept. 20-25, 1981.

79
MSS°1MA (rev. 2-80

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

l 1„ PUBLICATION OR

Ij REPORT NO.

2. Performing Organ. Report No. 3. Publication Date

SHEET (See instructions) 1 NBSIR 81 - 2447 January 1982

4. TITLE AND SUBTITLE

1981 Annual Report

Office of Standard Reference Materials

5. AUTHOR(S)

6. A. Uriano and S. D. Rasberry, Editors

§. PERFORMING ORGANIZATION (If joint or other than N BS, see in struction s) 1. Contract/Grant No.

&l&T!©yAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

8. Type of Report & Period Covered

SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City. State , ZIP)

SUPPLEMENTARY NOTES

~| Document describes a computer program; SF-185, FIPS Software Summary, is attached.

II. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here)

This report summarizes the technical activities of the Standard

Reference Materials (SRM) program of the National Bureau of Standards,

Status reports for SRM research and production projects are included

in the areas of electrical properties, thermal properties, radioactivity, chemical composition, chemical stability, mechanical properties and optical properties. Projects covered are carried out by

technical centers in the National Measurement Laboratory, National

Engineering Laboratory, and the Institute for Computer Sciences and

Technology. Also covered are a number of cooperative projects with

other laboratories and SRM activities of a number of industrial

research associates.

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semi colon s) Analytical Chemistry; compositional analysis; physico-chemical properties;

quality assurance; reference methods; Standard Reference Materials

13. AVAILABILITY

12

' Uni imited

[5^] For Official Distribution. Do Not Release to NTIS

221 Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402.

1 | Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

85

15. Price

$10.50

USCOMM-DC 6043-P80

\I