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/NBS research reports QC100 .U57 SP 680-4;1985 C.1 NBS-PUB-R 1

U.S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

NBS SPECIAL PUBLICATION 680-4

n i uo

lib 7

| No. 680-4

198b
Cover photo: Research chemist Susan F. Stone prepares a homogenized human liver sample for chemical analysis

in the clean laboratory of the

NBS environmental specimen

bank, which is being used to preserve hundreds of samples

of human tissue and environmental specimens. See page

22.
'/ —' CONTENTS

NATIONAL E'JREAU OF STANDARDS

iiERAHY

NBS

Research

Reports

Research UpdatG o NBS High-Tech Ceramics Program Geared to Needs of Industry c

j NBS Advanced-Ceramics Expertise,

Facilities Available to Industry 10

Fiber Optics: Lighting the Way to a Communications Revolution 13

New Technique for Measuring Antenna

Performance Pays Off 16

Seven NBS Inventions Picked as Significant

Technological Advances 19

Assets' Frozen as Researchers Put Pollution Problems on Ice 22

New Instrument Allows Observation of Surface

Magnetic Microstructure 24

Open Systems in Software 25

New Publications 30

Conference Calendar 32

U.S. DEPARTMENT OF COMMERCE

Malcolm Baldrige, Secretary

National Bureau of Standards

Ernest Ambler, Director

National Bureau of Standards

Gaithersburg, MD 20899

301/921-1000

National Bureau of Standards

Boulder, CO 80303

303/497-3000

September 1985 NBS Special Publication 680-4 Prepared by the Public Information Division Sharon Shaffer, Editor A903 Administration Building National Bureau of Standards

Gaithersburg, MD 20899

301/921-3181

Library of Congress

Catalog Card Number: 85-600575

CODEN: XNBSAV

Any mention of commercial products

is for information only; it does not imply recommendation or endorsement

by the National Bureau of Standards

nor does it imply that the products mentioned are necessarily the best

available for the purpose.

1
RESEARCH UPDATE

IRST COMMERCIAL SPACEMADE PRODUCTS SOLD

The first sales of a product

manufactured in space were announced July 17 by NBS. Bil- lions of tiny polystyrene spheres made

aboard a NASA space shuttle flight are being offered as an NBS Standard Refer- ence Material. "They will be used to im- prove microscopic measurements made

throughout the economy in electronics,

medicine, and other high-technology ar- eas," NBS Director Ernest Ambler said. The space-made spheres, each 10 mi- crometers (1/2500 of an inch) in di- ameter, are being purchased by producers of finely ground powder products as

well as by technologists who monitor en- vironmental particulate pollution from in- dustrial and chemical plants. They also

will be used by medical researchers who

calibrate instruments to count blood cells and measure their shape and to perform

a wide variety of diagnostic

measurements.

Physicists Thomas R. Lettieri and

Arie W. Hartman (seated) are using

a high-resolution microscope to

photograph strings of 1 0-micrometer polystyrene spheres on glass

slides. They will measure the spacings between dots of light that optically mark the center of each sphere

to determine the average size and

quality of the space-made particles.

The billions of spheres were produced

using a chemical process developed for NASA by Lehigh University. When ASTM

learned about the high quality of the material, this group asked that NBS measure the spheres and make them avail- able to the public as a measurement

standard. Each unit is available in a

5-milliliter vial that contains about 30 million spheres. They are in a 0.4 percent

concentration by weight; the remainder is water. The price of Standard Reference

Material 1960, 1 0-Micrometer Polystyrene Spheres, is $384 per unit. Order

from the Office of Standard Reference

Materials, B311 Chemistry Building, National Bureau of Standards,

Gaithersburg, MD 20899, 301/921-2045.

ULSED-ELECTRON 4-MeV

VAN DE GRAAFF SOURCE

AVAILABLE

NBS has converted its 4-MeV

electron Van De Graaff accelerator to provide pulsed electron beams in addition to continuous beams. The

pulsed beams are useful for research in pulsed radiolysis; chemical kinetics; radi- ation dosimetry; and atomic, molecular,

and nuclear physics. They have energies

between 1.5 and 3 MeV; pulse widths of

5, 15, 50, 500, 1500, and 5000 nano- seconds; and a maximum beam current

of approximately 0.5 ampere. Access to the electron beam itself is available through Kapton, aluminum, or titanium windows. In addition, a number of bremsstrahlung targets for producing photon

spectra are also available. The facility is open to outside users. Interested re- searchers should write or call Dr. Charles

Dick, C216 Radiation Physics Building, National Bureau of Standards,

Gaithersburg, MD 20899, 301/921-2201.

ALIBRATION SERVICE FOR

| CONDUCTIVITY STANDARDS

INTRODUCED

NBS is offering a new special

test service for the calibration

of electrical conductivity standards for eddy current conductivity meters. Such

meters are used widely in the aerospace

and automotive industries for testing and

sorting nonferrous metals and alloys. The

new service provides conductivity cali- brations for standards ranging from 15 to 100 percent IACS (International An- nealed Copper Standard), measured at frequencies between 10 and 100 kHz. Special arrangements can be made for calibrations at user-specified frequencies.

Calibrations are made with an accuracy

of 0.15 percent of stated value and turn- around time is approximately 30 days.

The fee for a single calibration is approximately $100, and standards to be cali- brated must meet certain geometrical

specifications. For further information,

write or call George Free, B146 Metrol- ogy Building, National Bureau of Standards, Gaithersburg, MD 20899,

301/921-2715.

EW GENERATION OF GRAVITY METERS DEVELOPED

Scientists at the Joint Institute for Laboratory Astrophysics

have developed a new generation of portable absolute gravity meters which have been designed for geodetic,

geophysical, geological, tidal, and tec- tonic studies. The instruments use the

free fall method and consist of four parts: a drag-free dropping chamber, a longperiod isolation device, a stabilized laser, and the necessary timing electronics. Special emphasis was placed on making

this latest group of gravity meters durable and easy to use. A copy of a paper

describing the new gravity meters is available from Fred McGehan, Division 360.2, National Bureau of Standards,

Boulder, CO 80303, 303/497-3246.

OT BOX TESTS ENERGY

PERFORMANCE OF WALLS

Full-scale wall sections are being tested in NBS' new "cali- brated hot box" to better understand how heat, air, and moisture

are transferred through them. The tests are also being used in the development

of standard test methods that industry can use to evaluate the energy per- formance of different types of wall sys- tems under varying climate conditions.

Currently, these methods do not exist.
Moreover, NBS researchers plan to put the facility to work developing and veri- fying mathematical models that building

product manufacturers and designers can use to predict thermal performance.

Although there are about two dozen

other hot boxes in the country, this one

is unique because of its size and measurement precision and for the special research that will be conducted using the

facility. The NBS hot box can measure si- multaneously heat, air, and moisture flow

in full-scale building wall sections up to 10 feet high by 15 feet wide. Though the facility is not designed as a

testing service, the NBS researchers

look forward to working with industry on

unique problems. Inquiries regarding the

facility should be directed to Tom Faison,

B114 Building Research Building, National Bureau of Standards, Gaithersburg,

MD 20899, 301/921-3501.

LTRASENSITIVE EDDY CURRENT FLAW DETECTOR

DEVELOPED

NBS researchers have devel- oped an extremely sensitive

tool for characterizing materials and detecting flaws in conducting surfaces. The

novel instrument uses a superconducting

quantum interference device (SQUID) as an amplifier to detect small perturbations

of the electromagnetic field induced on

the surface by an eddy current probe. Current versions of the instrument are about 10,000 times more sensitive than

similar eddy current probes without SQUID's. The increased sensitivity does

not allow detection of flaws 10,000 times

smaller, but it offers the option of in- creasing the spatial resolution (size and

location of flaws) and signal-to-noise ratio (allowing operation in noisier environ- ments.) While the superconducting amplifier must be cooled with liquid helium,

newly developed techniques allow the probe and materials under test to remain

at room temperature. For more details, contact John C. Moulder, Division 430.0, National Bureau of Standards, Boulder,

CO 80303, 303/497-3937.

ATABASE AVAILABLE ON

BEHAVIOR OF SALTS IN SOLUTIONS

Industrial and chemical

engineers—including battery

manufacturers, producers of steam

power, environmentalists and oceanographers, users of soda and potash for

fertilizers, and others concerned with

salts—will be interested in a new NBS

computerized database for quantitatively

determining the physical and chemical

behavior of ions in solutions. GAMPHI

A Database of Activity and Osmotic Coefficients for Aqueous Electrolyte Solutions—written in Fortran 77, contains

information for 350 binary aqueous electrolyte solutions at 298.15 K. The computer codes can be used interactively to retrieve the data at a terminal, or they can be incorporated with in-house pro- grams to calculate values for specified concentrations. The computerized data- base may be purchased for $200 from

the Office of Standard Reference Data,

A323 Physics Building, National Bureau

of Standards, Gaithersburg, MD 20899,

301/921-2228.

EW REFERENCE MATERIALS

DEVELOPED FOR MICROANALYSIS

Analytical laboratories seeking

to ensure the accuracy of mi- croprobe analyses and instruments may

do so with a series of five Standard Ref- erence Materials (SRM's) now available from NBS. Designed for use with tech- niques such as electron-probe microanalysis and secondary-ion mass spectrometry, the SRM's are in the form of

20-milliliter-long glass rods. Each SRM in the new series has three different rods: one with a base composition and each of the other two doped with small amounts

of additional elements. The SRM's, Glasses for Microchemical

Analysis (SRM's 1871 through 1875), are

available for $196 each from the Office

of Standard Reference Materials, B311

Chemistry Building, National Bureau of Standards, Gaithersburg, MD 20899,

301/921-2045.

AP FOR SPECTROPHOTOMETRIC TRANSMITTANCE BEGUN

NBS has established a new

Measurement Assurance

Program (MAP) for laboratories measuring spectral transmittance. The pro- gram makes it possible to check the absolute calibration of spectrophotometers

against the NBS scale over a trans- mittance range of 0.92 to 0.001, as well as the wavelength accuracy of the spec- trophotometers. MAP's are special cali- bration programs developed by NBS that make it possible to evaluate the entire measurement system and procedures of a participating laboratory, rather than

simply the instruments used by that laboratory. The cost of the spectrophotometric transmittance MAP is $1,700. Details of the program are available from

Kenneth Eckerle, B306 Metrology Building, National Bureau of Standards,

Gaithersburg, MD 20899, 301/921-2791.

ITANIUM DENTAL CROWNS

TESTED AS ALTERNATIVE TO

ALLOYS

Titanium could offer dentists a

practical alternative for gold

and imported metals currently used

in dental crowns if the material proves

itself in clinical studies now beginning

at NBS. The first precision casting

of a pure titanium dental crown in the United States was made recently in the dental laboratories of the Paffenbarger

Research Center (PRC) of the American

Dental Association Health Foundation at NBS. "If titanium performs as well as tra- ditional gold alloys, it could replace the more expensive material for dental restorations, as well as the use of imported

nickel, cobalt, and chromium for dental appliances," says Dr. Nelson W. Rupp,

associate director of PRC and the first volunteer patient to receive a titanium dental restoration. Rupp's crown and

those being made for other volunteer patients will be observed by PRC/NBS

scientists for at least 2 years.

3
OTENTIAL SAVINGS IN AUTO INDUSTRY FRACTURE

CONTROL

Economic studies by NBS of the costs of fracture of structural materials indicate that about $3

billion a year (out of some $35 billion total national fracture costs) could be

saved in the automobile manufacturing

industry alone. NBS is joining with Ford Motor Company to study methods of realizing these savings through

modifications of design, materials selection, and manufacturing processes. The

study will consider the effects and capital

requirements of database development

in support of revised and updated codes

and standards, of development of im- proved materials that have less mechanical property variability, and of advanced

inspection systems and automated manufacturing equipment.

The study will be carried out by NBS'

Dr. Bruce Christ, who will spend the next year at Ford as a Commerce Department

Science and Technology Fellow, working

with Ford's economists, database experts, technical experts, and policymakers. The methodology developed

in the study will be published for use

throughout American industry. For more

information, write or call Dr. Bruce Christ,

Research Lab/Room 5 2065, Ford Research and Engineering Center, 2000

Rotunda Drive, P.O. Box 2053, Dearborn,

Ml 48121-2053, 313/323-1423, or Dr. Richard Reed, Division 430.0, National Bureau of Standards, Boulder, CO

80303, 303/497-3870.

EASUREMENTS REDUCE

LIMIT FOR ANISOTROPY

OF SPACE

Is there a preferred reference frame in space? According to Einstein's Theory of General Relativity, the answer is "no," and physicists at NBS have confirmed this with an experiment based on atomic clocks that is 300

times more sensitive than any previous

measurement. In a test of spatial anisotropy, NBS scientists made comparisons

between a hydrogen maser atomic clock and a clock based on laser-cooled beryl- lium ions stored in a magnetic trap. If there were a preferred direction in space,

the hydrogen maser would be relatively unaffected while the rate of the ion- based clock would be dependent on its orientation in space. The experiments,

conducted by Drs. John Prestage, John

Bollinger, Wayne Itano, and Dave Wineland, showed no dependence, within 100

mHz, of the relative clock rates on their orientation with respect to the sun or

fixed stars. This represents about a 300-fold improvement over the 1961

Hughes et al./Drever experiments based

on careful nuclear magnetic resonance measurements.

ATERIALS AIMED AT

BOOSTING ACCURACY OF

LEAD-IN-BLOOD TESTS

To improve the reliability of blood tests for determining

long-term exposure to lead, NBS has

developed a Standard Reference

Material (SRM) for calibrating the

laboratory instruments that measure

minute amounts of lead in blood. Wideranging results—some in error by as much as 200 percent—have been obtained in past studies by NBS and other agencies when blood samples with known lead concentrations were sent to various clinical laboratories for analysis.

Though analyses have improved in re- cent years due to refinements in tech- nology and increased quality control, there is still a need for a lead-in-blood standard as a reference for checking in- strument accuracy and analytical methods. The new SRM should fill this need. Each unit of the SRM contains four bottles of varying lead concentrations in por- cine blood; it sells for $104 per unit. Lead concentrations are 5.7, 30.5, 49.4,

and 73.2 micrograms per deciliter. Order

from the Office of Standard Reference

Materials, B311 Chemistry Building, National Bureau of Standards,

Gaithersburg, MD 20899, 301/921-2045.

HIO WEIGHTS AND MEASURES LAB AUTHORIZED TO

TEST DEVICES

The Ohio State Weights and

Measures Laboratory is the first state laboratory to be authorized by NBS

to test weighing and measuring devices

under the new National Type Evaluation Program (NTEP). The Ohio Department

of Agriculture requested the authorization

after expanding its Columbus facility to meet criteria and test procedures devel- oped by the National Conference on Weights and Measures (NCWM) for eval- uating electronic commercial weighing

and measuring devices. The Ohio laboratory contains an environmental chamber

and specialized equipment for testing the

shielding on equipment against unwanted

electronic interferences such as the ef- fects of CB radio signals on highway

truck scales. NTEP was established in cooperation between NBS and NCWM to offer manufacturers a one-time evaluation of new weighing and measuring de- vices by either NBS or one of the states

that will be accepted by all of the others,

thereby eliminating duplicate tests by

each jurisdiction.

OVEL INVENTION AIMED AT

BETTERING FLOW

MEASUREMENTS

Two NBS researchers have

been granted a patent for in- venting an electronic circuit that can be

used in a flowmeter to determine, among

other things, the volume flowrate or steam flowing in a pipe. James E. Potzick and Dr. Baldwin Robertson have re- ceived patent number 4,520,320 for their "synchronous phase marker and ampli- tude detector." This device has the ability to measure the phase and amplitude

of a sine wave buried in noise. Though

designed as part of an acoustic flow- meter patented last year, the detector can also be used, Potzick and Robertson

claim, for phase and amplitude measurements in other research situations where the frequency of a signal is known

but the signal-to-noise ratio is much less than 1.

4
Program Ge

In the NBS fracture laboratory, Dr. Brian Lawn follows crack

growth on a computer monitor as a ceramic specimen is tested to failure.

odern technology has embarked

on an age-old quest to turn base

materials into "gold." But this time the pursuit is not alchemy; it is the manufacture of advanced

ceramics.

And lead isn't one of the pri- mary candidates for trans- formation, either, but other com- mon constituents of the Earth's

crust are. The starting materials

of the manufacturing process are generally fine powders syn- thesized from such abundant ele- ments as silicon and aluminum,

combined with oxygen, nitrogen, or carbon. Before processing,

these powders are usually

pressed into a mold or otherwise

compacted into the shape of the

final product.

The mechanisms of the final transformation are still somewhat

mysterious, but they generally re- quire more heat than incantation.

If all goes well, the result is an

engineered material whose

"gold" is its special properties.

Such properties might include made-to-order electrical re- sistance or optical birefringence,

among many other electrical/ electronic and optical possibilities.

Applications for electronic and

optical ceramics range from substrate materials, the tiny slabs of raw material for holding semiconductor chips—the most mature and lucrative application for hightechnology ceramics—to the fu- ture integrated optical circuit for switching and processing light signals without repeated conversion from electromagnetic

energy to electricity and back. The range of achievable mechanical properties is also broad. An adamantine hardness could combine with other desirable

properties, like extreme heat, cor- rosion, and wear resistance, to

make a structural ceramic capable of outperforming most other

materials in a hot, chemically

hostile, rugged environment.

Applications for structural ce- ramics are legion. Industrial cutting tools, for instance, could run

at higher speeds and last from 5

to 50 times longer if they were

coated properly with a ceramic

such as silicon nitride. Advanced

gas turbine and diesel engines

could be transformed by ceramics

such as silicon carbide, silicon ni- tride, and partially stabilized zir- conia. Capable of running at temperatures hundreds of degrees

higher than the top-performing

metal alloy engines, they could

deliver up to 50 percent more

miles to the gallon than today's

engines without the need for a water cooling system. Such en- gines could run on a broad class

of fuels, and burn them clean enough that today's hydrocarbon

emissions standards could be- come obsolete. But note that the operative

words in these scenarios are "if" and "would" and "could." Right now, electrical and electronics applications are the mainstay of today's $4.3 billion, free-world,

5
Dr. Stephen Hsu, foreground, and chemical engi- neer Richard Gates are shown in the NBS tribol- ogy laboratory with a 4-ball wear tester and

several ceramic heat-engine components. The wear tester is one of several special or unique

pieces of equipment researchers at NBS use to

study friction, lubrication, and wear.

high-technology ceramics market.

If that market is to grow to $25

billion or more by the year 2000, as some experts predict, many

technical barriers must be overcome.

Technical Problems

"We have found that we can make defect-free ceramics to get

enhanced properties, and we

have learned to vary the composition to get special properties," says Dr. Lyle Schwartz,

head of the Institute for Materials Science and Engineering at the

National Bureau of Standards. "But we don't understand the basic materials and mechanisms

well enough to achieve reliable, reproducible properties on a consistent basis."

Dr. Stephen Hsu, chief of the

institute's Inorganic Materials Di- vision, says this lack of understanding and control breeds "superstitious beliefs about what

practices you have to follow to achieve reliable properties from

the manufacturing process."

Knowledge and understanding

have to replace conventional

practice in the production pro- cess. Only then can hightechnology ceramics realize their potential. And what are the prospects?

Schwartz, who is a materials

scientist as well as director of the NBS materials institute, says, "the likelihood of technical suc- cess is very great, given sufficient

effort to fill in the gaps in ceramic

science and technology." And, he

adds, it is imperative that we do

so."The United States is in an in- ternational race to commercialize

a new generation of ceramic materials," he says, "and a single

example shows what's at stake.

"If the United States could commercialize ceramic engines

and completely dominate the market over the next 20 years, the economy would reap remarkable benefits," Schwartz claims. "Compared to no involvement in this technology, it could mean a

gain of $279 billion dollars in GNP, considering the full impact on the automotive industry,

among others, and 250,000 additional jobs. By the same token,

whatever fraction of the market we lose will, in proportion, erode

those gains. It will also negatively

affect our balance of trade." The prize for winning the ce- ramics competition is well worth an extreme effort on everybody's

part, he concludes. And he has

redoubled the Bureau's efforts in ceramics to meet industry's

needs for materials characterization, measurement and testing

techniques, standards, engineering data, and cooperative

technicai support.

Opportunities for

Cooperation

Special outreach activities complement the basic NBS hightechnology ceramics program be- cause, Schwartz says, "this industry needs more active support from us than just technical

consultation. NBS has one of the more versatile capabilities for ce- ramics research in the world, with a number of unique or special facilities and an extraordinary breadth of expertise [see page

10]. We have to keep in touch

with what is happening in industry

and make sure our program suits

their needs—and that they know

about it." At the present time, individual companies, other government
It Takes a Fine Touch

to Make a Tough Ceramic

Careful preparation and pro- cessing transform the raw materials of common ceramics,

the silicates, and other mineral compounds into highperformance materials vari- ously known as hightechnology, engineering,

advanced, or fine ceramics.

This transformation begins

with the chemical synthesis of powder compounds from ce- ramic precursors. Ideally, the powder, often a mixture of two

or more chemical compounds,

is made up of very fine, maybe

single-crystal, grains uniform in size. Unfortunately, small

grains tend to clump, forming

agglomerates, or larger nonuniform particles.

Usually a powder is doped

with small amounts of chemicals that aid "sintering." Sintering refers to the bonding

processes that occur during

agencies, and universities are working cooperatively with NBS

to exploit NBS expertise and fur- ther their own aims. These cooperative interactions include two

major ongoing data programs in- ternational in scope: one in x-ray powder diffraction and one in ce- ramic phase diagrams. Since di- rect person-to-person communication at the bench level is the most effective way to transfer technology, division chief Hsu

and the entire staff of the NBS In- organic Materials Division encour- age and seek new opportunities

for cooperation.

Researchers from outside NBS

come to Bureau laboratories pri- marily through the Industrial Research Associate Program and

the firing of a "green ceramic,"

which is powder compacted

into the shape of the final product. Heat causes the solid particles of the compact to co- alesce, or density, along their boundaries.

If the powder is free of traces of unwanted chemicals,

if the particles are fine and uni- form enough, evenly distrib- uted, and tightly packed, and if sintering occurs to the max- imum extent, the resulting material will be free of unwanted

inclusions and pores and

therefore totally dense and

flawless. Barring surface defects caused by finishing, this product will exhibit desired

special properties and possess

the maximum strength possible, given the material's specific atomic structures and

microstructure. A defect-free structural ce- ramic can generally withstand

the Guest Worker Program. Results of cooperative efforts are made public. Several unique NBS

facilities may also be used on a

limited proprietary basis by private

organizations, for a fee.* One recent major outreach effort, an NBS cosponsored confer- ence on the future of the U.S. ad- vanced ceramics industry, gave

both perspective and direction to the national effort in hightechnology ceramics. A summary

of that conference is found on page 8.

For more information on cooperative pro- grams in ceramics or the use of ceramic

facilities, call or write Dr. Stephen Hsu, A257 Materials Building, National Bureau

of Standards, Gaithersburg, MD 20899, 301/921-2845.

compressive loads and hostile environments, including corrosive chemicals and extreme

heat, better than any other

material. The microstructure can be engineered, by doping,

to give a ceramic some of the toughness characteristic of metals, but there are tradeoffs. Temperature resistance might be lowered, for instance,

or strength compromised.

Pores or unwanted inclu- sions trapped among the bonded particles, or surface cracks introduced by machining, also weaken the material.

In fact, the strength of a ce- ramic is in inverse proportion

to the size of its largest defect. And when a high-technology

ceramic part is stressed be- yond the limit of its strength, it performs like a crystal chandelier at a Wagnerian opera. It shatters.

Groundwork

The NBS advanced-ceramics pro- gram wasn't built in a day. Plan- ning started in earnest in 1980

when Samuel Schneider, a ce- ramist with 30 years' experience

at NBS, focused on the future prospects of a new generation of ceramic materials. "I wanted to explore the potential of ceramics

for many different applications to meet national needs," Schneider

says. "It was obvious that ce- ramics could be the answer to many advanced technological

questions, especially where high

temperatures or other special re- quirements make metals and

polymers unsuitable. I would say
the majority of high-technology

products in the future will involve ceramics.

"Simultaneously [in the early

1980's], as it so often happens in science, a wave of interest in ce- ramics was growing worldwide,

particularly in Japan. Japan was

beginning to capture many of our

high-tech markets at that time. Looking down the pike, I could

clearly see there should be

advanced-ceramics research at NBS. We have been in ceramics

since 1910 and always at the

forefront." But what should the Bureau's

role be in advanced ceramics? To

answer that question, Schneider

initiated three major studies: a broad technological/economic

study and a study of the scientific aspects of advanced ceramics as

related to technological needs,

both carried out by experts out- side NBS, and a study of the in- dustrial advanced-ceramics envi- ronment, carried out by NBS

technical staff "to give us a firstNBS researchers arebreaking new ground and

upsetting old theories

at the forefront of

ceramic measurement

science and technology.

hand idea of where industry is, where it wants to go, and what it needs from us." The studies revealed that NBS'

expertise is needed most in the areas of: 1) measuring and under- standing how defects develop

and evolve in the microstructures

during powder synthesis, forming

and compaction, firing, and machining; 2) understanding how the microstructure relates to the properties and performance of the fin- ished material under conditions of simulated and actual use; and 3) understanding how the variables

of the production process relate

to the development of the microstructure. Goal of the NBS Program:

Reliability by Design

NBS' Hsu is a leading expert in tribology, the study of friction and

wear. He points out: "Most people are confused about measuring

friction and wear. People measure wear and report the accompanying frictional force. Yet wear

is a cumulative process and fric- tion is an instantaneous quantity.

In ceramics, assumptions that we

take for granted in metal systems

are no longer valid. Entirely differ- ent procedures need to be devel- oped for measuring ceramic fric- tion and ceramic wear."

Dr. Brian Lawn, who is doing

fracture experiments to determine

what makes ceramics tough,

comments: "All the old theories about how cracks in ceramics be- have up to the point of failure need to be reassessed. When we

actually look at cracks growing in in-situ experiments we see someIndustry Must Be More Active

for U.S. to Compete

in Advanced-Ceramics Market

U.S. industry must take the lead and more aggressively exploit the

potential of new advanced, or high-technology, ceramics. That was the consensus of 140 industry, government, and university leaders who attended a confer- ence on the future of advanced

ceramics held by the Commerce

Department at the National Bu- reau of Standards July 10-11. To withstand fierce foreign

competition, "we have to get our

act together," asserted Albert R.C. Westwood, Martin Marietta Corporation's corporate director

of research and development.

Among many recommended actions, Westwood urged industry

managers to "overcome the commitment gap" by identifying and

tackling pivotal technical chal- lenges, targeting market niches

that can be gained early, and de- veloping bold and focused pro- grams with accelerated

schedules. Rep. Don Ritter, R-Pa., told conference participants, "Nowhere is the competition in inter- national trade more evident than

in modern ceramic technology.

There is still today in the United States only a weak U.S. industry

in high-technology ceramics while

the Japanese have made a strong commitment to become

the major world source of these

materials." Like other speakers at the session, Ritter said U.S. industry

"must accept responsibility for the bulk of the work needed to be

a successful competitor in the world marketplace." The govern- ment can help, he said, but "massive government intervention cannot achieve competitiveness in any industry."

Estimates of the value of the ceramic market by the end of the century vary from $10 billion to $50 billion. The current market is about $4.3 billion. Japan's share

of the market is about 45 percent

and growing, while the U.S. share

is near 35 percent and shrinking.

An economic study done by Charles River Associates, Inc., for NBS was reported on at the con- ference by CRA vice president
thing very surprising. Cracks grow

in quantum jumps. Even more

surprising, we're finding that the

critical events responsible for these jumps occur way behind

the crack tip, contrary to what ev- erybody has believed up to this time. We are currently re- formulating the theory of ceramic

toughness. Ultimately, we aim to be able to tell the processing

people who make the ceramics

exactly how they should tailor their materials for optimal

toughness."

NBS researchers like Hsu and

Lawn are breaking new ground

and upsetting old theories at the

forefront of ceranrvc measurement

science and technology. While some researchers are studying

ceramic precursors and examining powders produced by vari- ous techniques, including colloidal and solution chemistry and gas- plasma laser techniques, others

are studying the agglomerates

formed by spray-drying powders

and the porosity in "green"

S.L. Blum. The study showed that though the United States is still ahead in basic research, Japan is quicker to capitalize on research and is ahead in process, or production, technology. Also, "Japan- ese firms already have earned

large market shares in existing electronic ceramic applications

and are well positioned to take advantage of spillover effects from these to other applications,

particularly structural applications," Blum said. Recent cooperative efforts in ceramics, including the formation

of several research consortia at universities, also were applauded

by Westwood of Martin Marietta. He warned, though, that "this re- sponse will not be enough to ensure that U.S. companies win

their 'fair share' of emerging U.S. and world markets...." For this to happen, Westwood asserted, U.S.

(formed but unfired) ceramics.

Still other researchers are applying various traditional and

state-of-the-art processing technologies, including hot pressing

and hot isostatic pressing for structural materials and co- evaporation techniques for electronic/optical thin films, and

investigating the formation of grain boundaries and other sin- tering mechanisms. And, finally, they are investigating totally new

materials and determining the chemical and physical properties

and the performance of the final product.

Hsu has designed this broad- based but carefully focused NBS

program to accomplish some very

specific goals. "We want to deter- mine the critical materials parameters that control the properties

and the in-service performance of high-tech ceramic materials and

develop measurement techniques

and data to monitor these

materials parameters," Hsu

declares.

industrial management must de- velop a long-term commitment to exploit advanced ceramics in a

variety of new and existing markets, spur materials scientists in their ceramics work, and do a

better job of collecting and utiliz- ing technical knowledge about

ceramics generated in this country and abroad. NBS director Ernest Ambler

noted the recent improvement in U.S. industry/government/

university cooperation in a range

of research and development ar- eas and stressed that the federal government had a key part to play in advanced ceramics by being the catalyst for industry inter- actions. Ambler cited NBS cooperative programs that bring

industry researchers to work at NBS laboratories. He also told conference participants that the NBS advanced-ceramics program

has been strengthened to make it

The other aims of the program,

according to Hsu, are to develop

the scientific understanding of how microstructures evolve through various processing

stages, to determine the re- lationship between microstructure and mechanical and electrical properties, to identify the pro- cessing parameters that control the microstructure and other crit- ical phenomena, and to provide

theoretical models, phase dia- grams, measurement methods,

Standard Reference Materials,

and materials property data so

U.S. industry can optimize and

control the effects of hightechnology ceramic design and

processing.

With the information from studies like these rather than superstition and incantation, industry

may be able to turn base materials into products with golden

properties.

by Julianne Chappell

NBS Writer-Editor

more responsive to industry/

university needs for data, measurement methods, and

standards. Conference participants agreed on the most critical areas for re- search and development and on

the necessity for inter- and intra- industry cooperation to encour- age growth, productivity, and

competitiveness for U.S. ad- vanced ceramics. The De- partment of Commerce was

asked to help form an industrial steering committee to encourage

that cooperation by investigating the feasibility of joint research and development efforts. To obtain a complete summary

of the conference, write or call Samuel Schneider, B309 Materials Building, National Bureau of Standards, Gaithersburg, MD

20899, 301/921-2891.
o be successful, the advanced

ceramics industry needs

measurement-related science and

technology such as measurement

methods for ceramic structures and properties, generic materials- property data, and well- characterized reference materials from the National Bureau of Standards. This was the main point

made last spring by Dr. William R. Prindle of Corning Glass Works

when he testified before a sub- committee of the U.S. House of Representatives' Committee on

Science and Technology.

Prindle, Coming's director of administrative and technical ser- vices, was testifying to the Bureau's wisdom in attempting to augment its existing, in his words,

"world-class activities and facili- ties" dedicated to advancedceramics research.

Prindle and other industry lead- ers support NBS because it has

"a proven track record in providDr. Kay Hardman-Rhyne is about to subject a ceramic

specimen to small-angle neutron scattering experiments

at the 20-megawatt NBS re- search reactor.

ing successful technology transfer

that is needed by industry," Prindle told Congress.

Dr. Stephen Hsu, chief of the NBS Inorganic Materials Division,

knows the ingredients of this success: the right facilities, the right programs, the right people, and a

willingness to go more than half way to get the others involved. "The door to every laboratory is open," Hsu says, "and we have

experts in every ceramics area and across all disciplines. Wherever cooperation of mutual benefit is possible, we pursue it. It is the best way we know to make a two-way exchange of knowledge

and technology."

Hsu invites industry managers

and researchers involved in ad- vanced ceramics to visit the NBS

laboratories in Gaithersburg, Md.,

and to meet the staff of the Inor- ganic Materials Division. Visits can be arranged by calling Hsu

on 301/921-2845. In the meantime, here is a brief overview of the research expertise and

facilities. A Wide Range of

Research

Dr. Edwin Fuller, who heads the NBS efforts in sintering science,

says the Bureau addresses all generic, measurement-related areas

of advanced-ceramics science and

technology. Precursors are studied; powders are synthesized,

characterized, and compacted;

green ceramics are characterized and processed; evolution of the microstructure during production

is monitored; and sintering mechanisms are investigated.

Finally, the physical and mechanical properties of finished materials are determined, and

materials are performance tested under conditions of simulated

use. Such tests give researchers

the opportunity to test theories of how ceramics fail, or conversely

to find out what makes them suc- ceed. Results in all areas are

used to revise old or develop new

theories and, most important, to

link performance to basic properties, properties to structure, and

structure to the manufacturing

process. Properties/performance testing also satisfies some of industry's

immediate needs, Fuller says, and thus constitutes a bridge be- tween industrial applications and

NBS' basic studies. "Most of the

finished structural and optical/ electronic ceramics performance

tested at NBS come from manufacturers, and the test results serve their near-term purposes in product development as much as

they do our long-term goals," he

points out. Most companies are pleased

with the expertise they find at the Bureau and with the divergent fo- cuses of their near-term and

NBS' long-term research. "One

senior engineer from an engine

company told me they found our

testing so useful they decided to copy our mechanical properties

and performance lab," Fuller says. "They've even duplicated some of the special purpose

measurement equipment we've

developed here."

Optical/Electronic

Ceramics

The general theme of basic sci- ence and technology for future applications holds true in the

optical/electronic area, according

to Dr. Albert Feldman. Feldman, a

physicist, directs the NBS opticalceramics program. He has in fact been contributing to the future of opticalceramics technology since he

joined NBS in the 1960's. And he

gives one example of how NBS

draws on expertise developed in the past to advance measurement science for the future: "Bismuth silicon oxide is one of the important optical ceramics to- day, but we first looked at it in the
late 1960's, soon after it was de- veloped at Bell labs." BSO, as

the material is called, rotates the

polarization of a beam of light passing through it. In other words,

it makes light particles rotate in one direction only. "We at NBS

developed and characterized a new BSO material with the opposite sense of polarization rotation," Feldman adds. Today BSO is a candidate for optical memories that may be

found in an optical computer of the future. And NBS is again

studying this material. "Exposure

to light changes a basic optica!

property of BSO, and this behavior is desirable," Feldman explains. "But nobody yet under- stands what mediates the

behavior. We think it is caused by

impurities, but we don't yet know

what those impurities are." Of course, BSO is but one of many optical materials NBS is studying. Materials for multi- function devices, also known as

integrated optics, are high on the

priority lists of manufacturers,

who provide sample materials for study. But the Bureau is looking

farther into the future than a hybrid optical circuit made up of both non-ceramic electronic materials and ceramic optical materials. "That will be the next generation," Feldman says. "After that

will probably come a generation

of monolithic [or single-material]

optical circuits made up of nonceramics. But then, we may have

a generation beyond that of monolithic ceramic devices that

will use ceramics for both optical

and electronic functions." Feldman is optimistic because

he and other NBS researchers

are using a relatively new pro- cessing technique, called co- evaporation, to develop totally new thin films, materials that do

not exist in nature and have

never before been produced.

These thin-film materials have

current application in advanced

optical coatings. Other processing

techniques for optical materials in use at NBS include electron- beam and ion-assisted electron- beam deposition and sputtering.

Techniques used for characterizing chemical composition and

structure include: x-ray diffraction and electron microscopy for materials structure; electron spec- troscopy for chemical analysis;

Auger spectroscopy, secondary

ion mass spectroscopy, and

Rutherford backscattering for depth profiling; and Raman spec- troscopy for ionic bonding. For

optical characterization, NBS re- searchers employ channel spectra analysis, m-line spectroscopy,

optical scatter, and optical absorption among other techniques.

Powder Synthesis,

Processing, and

Characterization

In the area of structural ceramics,

Dr. Kay Hardman-Rhyne and Dr. Alan Dragoo, both chemists, head

the groups most directly involved

in powder synthesis and compaction and in the characterization of powders and green

ceramics.

Hardman-Rhyne uses several powder-synthesis techniques, in- cluding the sol-gel method, precipitation, other chemical means, and gas-plasma methods. She

uses the Bureau's 20-megawatt

research nuclear reactor for small-angle neutron scattering

and wide-angle neutron diffraction studies of green ceramics and fin- ished materials to determine crystal structure and characterize microdefects. Dragoo's group is concerned

with characterization, including

crystal structure and physical

properties, of powders after synthesis and prior to compaction. Of

particular interest are powder par950

850

750

650

'

I

I

1 1

1

1

\ y

'Liq. + CoO / 7 + CaO

L. 7ss

|

yss+

3:7 / — /

/ / s*' /

^| /a'ss + 5:7 3Bi2 03 -7CaO -

+CaO

ass /

o

o O

o

oo

'CaO

aBi203 _ +

m

d?m

1

O

o

to

1^o

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in o

CD

1

1

1 0

3i 2 03

20 60

Mol %

::

CaO

This bismuth oxide/calcium oxide phase diagram

comes from a computerized database being developed by NBS and the American Ceramic Society under their jointly funded multimillion-dollar

Phase Diagrams for Ceramists Program.

tides, or agglomerates, produced

by the spray drying of powders.

"We want to know what signa- tures identify a powder as one

that will density," Dragoo says. "Manufacturers will be able to specify what they want in a powder once we determine what

measurements are critical." Fuller studies the transport

mechanisms and the kinetics of sintering and the physical properties of sintered materials. He is interested in techniques that give information on structure and grain boundaries.

Dr. John Hastie leads a group

concerned with high-temperature

chemistry. Hastie's group in- cludes the ceramics phase dia- gram data center at NBS. The

1

1
Research chemist Carl

Robbins is using a computerized image analysis system to

quantitatively analyze an en- larged photograph of ceramic

powders.

program, a joint NBS/American

Ceramic Society effort, is under- going a major expansion: The

American Ceramic Society is working to raise $4 million to support its share of the effort. "There

are about 20,000 phase diagrams

out there in the literature that need to be collected, evaluated,

and published," he says. "That's what we're doing with the help of experts all over the world. And

we're also developing a computerized database that will one day

be accessible through the Ameri- can Ceramic Society to subscribers everywhere."

Phase diagrams are graphic

representations of information about the physical and chemical

states of materials and the ther- modynamic transitions between

phases, with emphasis on the

crystalline phases. Ceramists and

engineers use them to choose

and design materials for particular

applications. The NBS/American

Ceramic Society ceramics phase

diagram program will put about $1

billion worth of research to better use, Hastie claims. NBS facilities for materials

characterization include x-ray dif- fraction equipment; scanning and

scanning-transmission electron microscopes; capacitance/

impedance equipment for measuring complex a.c. properties;

particle-sizing equipment such as an x-ray sedigraph for measuring

the rate of settling of particles out

of a liquid and a photon correlation spectrometer for measuring particle size by light scattering due to the Brownian motion

of particles; a 3-point BET apparatus for surface-area measurement; and a mercury porosi- meter for measuring pores

connected to the outsides of particles. NBS researchers are working on a technique called x-ray

line broadening to measure grain

size, and they are augmenting an

image-analysis technique for determining the size and shape of powder particles and the properties and structure of a finished

material. Sintering is accomplished at NBS by a variety of methods,

ranging from hot pressing to hot

isostatic pressing. A number of conventional tube-type furnaces have been modified for special at- mospheric environments. A

tungsten-mesh furnace can go to 2500 °C. One induction hightemperature furnace operates in a

special enclosure, uses a highfrequency field, and works something like a transformer to achieve

temperatures up to 2600 °C.

Mechanical Properties

and Performance

In mechanical properties and per- formance, NBS researchers study

the processes affecting the structural reliability and performance of ceramics over a range of temperatures and in aggressive environments. Theoretical and experimental work is aimed at understanding fracture and defor- mation mechanisms and their re- lationships to microstructure.

Dr. Sheldon Wiederhorn, a chemical engineer, leads the group primarily responsible for determining mechanical properties at low and high temperatures,

looking at materials performance

under a variety of conditions, and

determining failure mechanisms

and materials durability.

Hsu's group focuses on

tribology—friction and wear

studies. Dr. Stephen Freiman

heads the group concerned with the mechanical properties and

performance of composites. Also,

Freiman's group has developed a thermal-wave nondestructive technique for monitoring the mi- crostructure of a ceramic during

and after sintering. With modifications, the technique may one

day prove useful as part of a production line system for monitoring and controlling the manufacturing process.

Special facilities in these areas

include mechanical test equipment such as general purpose

universal test machines; a hightemperature controlled- environment facility for testing in a fossil-fuel combustion environ- ment; a high-temperature creep

laboratory; a high-temperature,

high-pressure facility with temperatures as high as 1000 °C and

pressures as high as 1000 psi; a green-ceramics laboratory with a high-temperature vacuum facility; hydrothermal test equipment; a unique dynamic hardness tester; and a newly developed and

unique tribometer for testing fric- tion and wear at temperatures up

to 1500 °C. The x-ray facilities for microstructural analysis are being

increased and enhanced to per- mit better characterization, including measurement of residual

stress. J.C.

12
ptical fibers. These hair-thin strands of glass or plastic that conduct light have long been

used for tasks as simple as looking pretty—like the miniature light "trees" with branches that sparkle at their tips. Now they are being used to light the way to a rev- olution in the way we

communicate. That is why re- searchers at NBS are devoting

their energies to help U.S. industry speed the use of optical fibers. Practically everyone in the tele- communications business agrees

that optical fibers are the wave of the future in moving information from place to place. As NBS

physicist Doug Franzen puts it, "The prevailing mood seems to be very upbeat, with some people

suggesting that optical fibers will eventually replace nearly all the

long distance copper communications cable."

Optical fibers are rapidly being

introduced into all kinds of tele- communications applications,

from networks within single build- ings to intercity telephone links. They are used to send data from one computer to another and to send operating signals from a

plane's cockpit to control the engines, flaps, and other systems of the aircraft. There are two main reasons for the sudden growth of applications

using fiber optics: their huge capacity for rapidly moving large

amounts of information and their immunity from electrical inter- ference from outside sources. "Since the information is carried by light waves inside an insulator,

such things as lightning, sparks,

Here electrical engineer Robert Gallawa measures the bandwidth of multimode optical fibers. The measurements are done using three different techniques: frequency domain,

time domain, and pulse spectrum analysis.

motors, and other common

sources of electrical interference have no effect," Franzen says, adding that optical fibers "make

ideal communication links in electrically noisy environments."

Optical fibers also provide highsecurity communications because

the information in the cable can't be tapped without physically at- tacking the cable, "and that al- ways leaves a telltale trace," Franzen says. A rapidly expanding technology

such as fiber optics always has

growing pains of one sort or another, and this is where NBS

comes in. As a non-regulatory re- search agency, NBS' work pro- motes compatibility among components, especially through

uniformity of measurements. Most

basically, when new concepts

and novel terminology are being invented so fast, it is hard for ev- eryone to keep up with and agree on definitions. And when the

state of the art is advancing rapidly, it is difficult for users, re- searchers, and manufacturers to reach a consensus about the best way to measure a given pa- rameter, even if the parameter is well defined.

All this brings a certain amount

of chaos to the marketplace. Buyers and sellers don't understand

and follow each other's specifications, leading to disputes over whether contracts have been satisfied. What's more, when measurements on the optical fiber systems are made independently

using different methods, the re- sults seldom match, leading to further disputes. This was the situation facing the fiber optics industry until the major manufacturers, some im- portant users, and NBS got to- gether to work out these

problems.

One of the first accomplishments was the compilation of

'3
a glossary of terms used in fiber optics communications, which al- ready has been adopted and published by the Institute of Electrical and Electronics Engineers. Drawing on the expert opinions of a

large panel of industry and NBS

representatives, the glossary defines more than 400 terms commonly used in the industry. It pro- motes clearer language and less confusion in contracts, specifications, and technical papers writ- ten about fiber optics. "This may seem like a rather elementary

job," says Franzen, "but we

found that the language differ- ences among optical fiber pro- How Optical Fibers Work

Telecommunications-grade optical fibers are usually made of very pure glass, because impurities tend to absorb and

scatter the light. This scattering weakens the intensity and

reduces the distance the light can travel through the fiber without extra amplification.

Other conditions which dim, or attenuate, the light include

variations in the diameter and

micro-bends in the fiber. There are two basic kinds of

fibers: those with a constant

index of refraction from the center out to the surface and

those with an index that gradually decreases from the center

out. Both kinds usually have a separate low-index covering

that enhances the trans- mission properties. Then the fi- ber is surrounded by a plastic buffer coating for protection.

As light rays pass through

the constant-index fiber, most

of them strike the walls at grazing angles and are totally reflected, so little light escapes

through the wall of the fiber. However, if the surface of the

fiber or covering is uneven or scratched, or if the fiber is bent in a small radius, losses can increase.

In graded-index fibers, light

is guided in a similar fashion except that the gradually

changing index of refraction bends the light instead of reflecting it. Most of the light is confined to the central axial region of the fiber, because if a ray leaves this region, it is bent back toward the center. The main advantage of graded-index fiber is higher

frequency operation.

The higher frequencies are allowed because almost all of the light travels the same path

length through the fiber (single-mode operation) and

the pulses of light that carry the information can be closer together without getting mixed

up. In constant-index fibers, the rays can bounce around in many ways, taking many differ- ent paths, some longer than

others. By the time they reach

the other end, two pulses that started out separately might

arrive at the same time and

get mixed together, destroying the information each carries. This is a result of multimode

operation, and it limits the fre- quency of pulses to a certain value. The pulses of light are generated by light-emitting diodes

or lasers controlled by electronic circuits. The light can be

focused on one end of the fi- ber by a tiny lens, and a similar lens assembly can be at- tached to the opposite end to focus the output beam on a

photodetector. The photodetector turns the light pulses

into electronic impulses which

are interpreted by more computer circuits.

If the distance to be covered

is too great for a single length

of fiber (the present limit is 30

miles or so), several fibers can be alternated with amplifiers.

The amplifier, or "repeater", detects the weak output of one fiber, converts it to an

electronic signal that drives a diode or laser, and retransmits the new strong light pulses to the end of the next length of

fiber. This process can be re- peated as many times as nec- essary to cover the distance

desired. The information is received

at the far end of the fiber by a

photodetector, usually another

kind of diode, that converts

the light pulses into electrical signals that can be processed

by computet circuits or sent on

wires to their ultimate

destination. Each of these transitions from device to fiber to device, as well as the losses in the fi- bers themselves, saps a little of the light's strength, but these losses can be minimized

with careful attention to the

characteristics of all of the components. This requires pre- cise measurement of the opti- cal and electrical properties of each item in the light path, so

that the design of the entire system can be optimized.
ducers and users were an im- portant barrier affecting the

industry."

NBS and the industry, working

through the Electronic Industries Association, have started to de- velop voluntary standards for the methods of measuring the properties of optical fibers so that when

different laboratories measure a

given fiber they obtain comparable results.

In order to carry useful amounts of information over long

distances, the fibers must be

made very precisely. Their di- ameters must be held constant to a few ten-millionths of an inch. Their purity must be extremely

high, and their optical properties

must be controlled so that they

vary in a precise manner over the cross section of the fiber. Once manufactured, the fibers must be tested, or measured, to see that they meet advertised

specifications. For instance, light gets dimmer, or is attenuated, as

it travels down the fiber; the amount of attenuation is one of the most important parameters

measured. Another is the bandwidth, which is a measure of how

much information can be trans- mitted over the fiber in a given

length of time. These and other measurements must be made on

NBS has developed standard measurement techniques or calibration ser- vices for bandwidth, core

diameter, index of refraction profile, and

attenuation.

samples at the factory before customer orders can be filled. Special connectors are used to attach the fibers to each other

and to light-sending and

-receiving devices. Designing the connectors requires knowledge of certain other fiber parameters,

such as the acceptance angle,

which describes the size of the

tiny cone of light leaving the end

of the fiber. Light outside that cone will not travel successfully

along the fiber, and will be

wasted. So measurements must

be made on the fibers and the devices connected to them to obtain optimum results. The difficulty with all this measuring activity is that the measured values too often turn out to depend on the method of measurement used. For example, one company measures its fiber and

certifies the amount of attenuation. Using his own techniques, a customer may measure more

attenuation. This means the cus- tomer may reject the fiber or he

may be led to design his system

to use more power than is needed to transmit over a given

distance, or use more "repeat- ers" or light amplifiers along the way. In any case, his costs are increased. One company estimated that its costs of reaching an agreement

on measurements with a certain large customer included some

400 staff hours of lab time, at least twice that much administrative time, and roughly 50,000

miles of travel. What's more, the customer probably spent a third to half as much time and money

as well. The solution is to use standardized measurement methods. NBS

has developed standard measurement techniques or cali- bration services for bandwidth, core diameter, index of refraction

profile, and attenuation. The Electronic Industries Association and

other standards groups have vol- untarily accepted these standards

for industry and other standards

As a non-regulatory re- search agency, NBS'

work promotes compatibility among components, especially

through uniformity of

measurements.

are being developed as the need

becomes apparent. Standardization brings other economic benefits because it al- lows firms to concentrate their technical activities on innovation,

especially cost-reducing inno- vations. This improves their competitive position in world as well as domestic markets, an im- portant consideration in the fiber- optics market where foreign competition is tough.

In this process of reaching an

industry-wide consensus on measurement standards and methodology, the crucial word is "vol- untary"; NBS has no regulatory powers. "What NBS can do," says Franzen, "is try to make a compelling scientific case for making a measurement in a certain way, so that the industry will agree that everyone's interests are best served by accepting the procedure as a voluntary industry standard. "So far," he adds, "we have

been fairly successful, but there are still substantial measurement

challenges facing NBS and the

industry. We need to work on

standards and measurement

techniques for evaluating such

things as light sources, detectors,

multiplexers, and the whole

gamut of integrated optical cir- cuits just now beginning to be

developed."

by Collier Smith

NBS Public Affairs Specialist

<5
he patience and persistence of National Bureau of Standards sci- entists and engineers have re- sulted in some big savings for U.S. industry.

The NBS researchers devel- oped a revolutionary new way of measuring the performance of ad- vanced microwave antennas that has, for example, saved RCA

over $6 million in building and

testing costs for the Aegis radar antennas which were installed on

16 U.S. Navy cruisers. The origins of the NBS devel- opment go back 25 years to a

project designed to provide an improved measurement of the speed of light. Theoretical calculations for that project, the re- searchers found, could also be

applied to the measurement of performance characteristics of mi- crowave antennas. Until recently,

virtually all antenna measurements were made on large,

outdoor (far-field) facilities. Measurement accuracies were typi- cally no better than plus or minus

Douglas T. Tamura, an electronics technician, aligns an- tennas being calibrated on

the extrapolation range which

is part of the near-field facility.

10 to 20 percent because of the

reflections, interference, and dis- tortions; the older techniques were not suitable for measuring

large, sophisticated satellite an- tennas or a new class of anten- nas called phased arrays. Rising land costs also made new out- door facilities prohibitively

expensive.

Beginning in 1973, NBS constructed a large indoor antenna measurement facility that allowed engineers to measure the phase

and amplitude distribution of the

fields directly in front of an an- tenna and, through the use of

their previously developed mathematical formulas, calculate the

far-field radiating characteristics

of the antenna. This method,

called the planar near-field scanning technique, was found to be

quite useful for satellite antennas and for the phased-array configuration, a grouping of many small antennas whose phases and amplitudes are electronically controlled to produce various beam

configurations and to point the beam in different directions. The new technique had the potential

for speeding up the measurement

process, improving accuracy, pro- viding more complete information,

and reducing both the staff needed and the cost. The next big hurdle was getting the near-field technique accepted

by industry and other government

agencies. "Companies had eco- nomic investments in far-field ranges, they were not going to be

amenable to a new scheme when

they had such a large in- vestment," says Charles K.S.

Miller, chief of the NBS Electro- magnetic Fields Division. "We were very concerned

about transferring the technology

and took advantage of opportunities as they came up," adds

Dr. Ramon C. Baird, leader of the NBS antenna systems metrology

group which developed the technique. Whenever members of his

group visited other government

agencies and private companies

they took the opportunity to explain the advantages of the nearfield technique.

Over the years, Baird's group

has presented 30 papers at national and international confer- ences, offered three courses on

near-field scanning at NBS in Boulder, and put on courses at NASA's Lewis Research Center,

Hughes Aircraft Company, Intel- sat, and TRW Corporation. Staff

...saved RCA over $6 million in building and test- ing costs for the Aegis

radar antennas which

were installed on 16 U.S.

Navy cruisers.

members also lectured at Califor- nia State University and the Technical University of Denmark.

The proselytizing began to pay

off. Gradually large aerospace

and defense firms, such as RCA

and Hughes, constructed nearfield antenna ranges and realized the advantages of this technique.

Hughes found that the near-field technique reduced the time needed to measure complex,

phased-array antennas for the

U.S. Army from 1 month to 12

hours. Dollar savings, often amounting to 1 percent of the value of the antennas, were as much as $22,000 each. "We've been using our nearfield facility for about years,"

says Dr. Robert D. Ward, a senior

project engineer in Hughes'

Space Communications Group at

El Segundo, Calif. "We started

getting good results immediately

and we've been very pleased."

Ward notes that his group is lo- cated in a congested area near

16
Measuring in

the Near Field

The making of near-field an- tenna measurements is a

three-fold process involving a

facility, a mathematical formulation, and a computer pro- gram. At the NBS Boulder lab- oratories, measurements are made in a 30-foot-high bay

which is lined from floor to

ceiling with dark blue, carbon- impregnated microwave ab- sorbing material. These ab- sorbers are designed to ensure the integrity of the measurements by sopping up

any stray microwave radiation and minimizing reflections and

distortions. The antenna to be

measured is mounted on a stand in front of a wall of ab- sorbing material. The antenna

remains stationary while measurements are being made. A

small antenna probe, in front of the absorber wall and

pointed at the antenna being

measured, moves in a plane

taking thousands of measurements at regularly spaced

points near the antenna. The next step—the mathematical manipulation of this near-field data into far-field patterns—was made possible

by the work of Dr. David M.

Kerns, an NBS scientist now

retired. In the 1960's, Kerns developed rigorous mathematical equations that could be used to calculate the farfield characteristics of an an- tenna from measurements

made in the near field. The basic mathematical operation is a

Fourier transformation which

allows a complicated radiation pattern to be expressed as the sum of a number of simple

plane waves. A series of computer programs, developed by

NBS' Allen C. Newell and his colleagues, perform these

computations quickly and per- mit a variety of measurement

parameters to be obtained on

a number of different antenna

configurations and

frequencies.

The far-field pattern, gain,

and polarization are three of the main antenna properties, or parameters, measured by

this technique. The far-field pattern is the angular distribu- tion of the antenna's energy

output at a great distance from

the antenna (in the far field). The far-field pattern of energy

distribution does not change

no matter how far out the measurement is made. Gain is a measure of how the energy

is focused or concentrated in a

given direction; it is analogous

to the focusing of light into a beam in an automobile headlight. In a radar system, for in- stance, the higher the gain of the radar antenna, the farther away an object can be detected. Polarization describes

the direction of the antenna's

electrical field. The near-field measurement

technique has a number of unique advantages: It can be

used at the end of an antenna

production line to evaluate per- formance, align elements, and

diagnose problems; it is especially useful for measuring

phased-array antennas; and it

is the method of choice for measuring many satellite an- tennas. In the case of newly

built antennas, the near-field method can identify deformities in the shape of reflec- tors which, if not corrected, could cause poor antenna per- formance. Similarly for phasedarray antennas (composed of hundreds of small antennas

electronically controlled to function as a single large one),

the near-field technique can

easily and quickly spot one of the small antennas that is out

of adjustment. Satellite anten- nas are often lightweight, unfurlable structures which operate effectively in the very low

or zero gravity environment of space but which pose problems

for ground-based testing as the

lightweight structures deform

easily. Near-field testing

virtually eliminates this problem

because, once mounted, satellite antennas do not have to be

moved for measurement purposes. NBS has tripled the size of

its near-field facility to accom- modate large antennas such

as the 25-foot-long, 4-foot-high

AWACS instrument. Measurements are still taken in a

plane, but researchers are also working to perfect cylindrical

and spherical scanning tech- niques. These new techniques

will permit 3-dimensional measurements and measurement

of sidelobes and backlobes

undesired radiation which

leaks out the sides or rear of the antenna. NBS' Dr. Paul F. Wacker, now retired, devel- oped a method for simplifying the calculations for the spherical technique and NBS elec- tronics engineer Richard L. Lewis developed computer

programs based on Wacker's

method. The Technical University of Denmark is now doing

practical tests using the spherical technique. The cylindrical

technique was first developed

and implemented at the Georgia Institute of Technology.

NBS has also developed computer programs for cylindrical

scanning which are now being

used in several laboratories throughout the world. NBS has

the capability for using all three (planar, cylindrical, and

spherical) measurement

techniques.
Engineering aide David Dean takes readings of phase shifter settings of the large (4 feet by

25 feet) AWACS antenna being measured in the newly enlarged near-field facility. Los Angeles International Airport.

"We can't build an outdoor range

easily. The fact that near-field measurements can be done in a room similar to an anechoic

chamber is a big advantage to us," he adds. The technology transfer efforts by NBS have made the near-field methods the dominant force in the evaluation and testing of

large, complex antennas. Eigh- teen U.S. companies and govern- ment agencies have now constructed about 30 major near-field

facilities. An additional 11 nearfield facilities have been built by

NATO and other allied countries.

In almost all cases, NBS has

been involved in either the design

of these facilities or in supplying

the computer programs. Even af- ter the facilities have been constructed, NBS continues to cali- brate probes used by these

organizations as part of the nearfield technique.

Dr. Alan E. Holley, a technical

staff manager at the Hughes'

Ground Systems Group in Fullerton, Calif., says he uses the

near-field technique as a diagnostic tool to check for flaws in complex phased-array antennas being

built for the U.S. Army. "We find things [flaws] that would never have been found on a far-field range," he explains.

Calling NBS in the "forefront"

of near-field technology, Dr. S.J. Hamada, manager of TRW's An- tenna Systems Laboratory in Redondo Beach, Calif., says his group is using the near-field tech- nique for acceptance testing on

all projects. "Nowadays, you can't

do far-field tests," he adds, noting

that state-of-the-art, highfrequency antennas would require a 7-mile-long outdoor test range. He terms near-field testing "the measurement of choice in the

future." NBS' involvement with the

near-field technique will continue

for some time. Its main near-field

facility at the Boulder laboratories was recently expanded so that large antennas can now be measured and calibrated. This facility

is available for use on a reim- bursable basis by industry, gov- ernment, and academia. Arrangements should be made with Allen

C. Newell, Division 723.05, National Bureau of Standards,

Boulder, CO 80303.

by Fred McGehan

NBS Public Affairs Specialist
Seven

nventions in computer science,

microelectronics, and automated

manufacturing were among seven

entries of the National Bureau of Standards given l-R 100 awards

this year. Those seven awards

represent the highest number

given to any single participant in this year's competition.

I-R 100 awards are given annually by Research & Development

magazine to honor the "100 most

significant" new technical prod- ucts of the preceding year. Presentations were made SepPictured here from the left are Richard J. Linn,

Jr., Jeffrey Gura, Daniel Rorrer, and Wayne

McCoy with (seated) J. Stephen Nightingale who

were presented with an l-R 100 award for developing a transport protocol test system. Not pictured are co-winners Thomas P. Blumer and

John C. Burruss.

George A. Candela (left) and Deane ChandlerHorowitz pose with their computer-controlled

principal-angle ellipsometer.

tember 26 in Chicago and bring

to 44 the number of l-R 100

awards NBS has received since it first started taking part in the competition in 1973.

Descriptions of the awardwinning technological advances

follow.

Transport Protocol Test

System

In July 1984, 14 computer manufacturers and communications

companies demonstrated for the

first time how computers from dif- ferent manufacturers could communicate using international net- working standards. The awardwinning transport protocol

test system developed by an NBS-led team helped make that demonstration possible. The sys- tem, the first of its kind, is a set

of complex software programs

that allows vendors and users to

self-test their computer systems

to make sure they conform to the networking standards. Included in the test system are a reference implementation, tests, a test inter- preter, and an exception or error generator. Until now, implementations of the network stan- dards were verified by using them

and then correcting errors as they were discovered. The test system

has been made available to pri- vate industries and has been

used successfully by major ven- dors and users. The winners of this l-R 100

award are Richard J. Linn, Jr., Wayne McCoy, J. Stephen

Nightingale, Daniel Rorrer, and

Jeffrey Gura, all from the NBS In- stitute for Computer Sciences and

Technology, and Thomas P. Blumer and John C. Burruss from

Bolt, Beranek and Newman, Inc.

Computer-Controlled

Principal-Angle Ellipsometer

Dr. George A. Candela and

Deane Chandler-Horowitz of the NBS Center for Electronics and

Electrical Engineering were hon- ored for developing a fully auto- mated, high-accuracy ellip- someter for measuring the optical

properties of thin films on various

materials. The device—which is modular and built mainly from

commercially available components—can determine the

The device.. .can determine the thickness and

refraction index of thin

films more accurately and

with greater ease than

previously possible.

thickness and refraction index of

thin films more accurately and

with greater ease than previously

possible. This is important to in- dustries such as semiconductor

manufacturers which need accurate ellipsometers to produce

quality products.

Candela and Horowitz' device, unlike commercially sold el- lipsometers, operates automatically at the principal angle.

Because of the instrument's ac- curacy, it can be used to make

reliable measurements on thin- film growth, monolayer surface contamination, surface damage,

or surface crystallography.

The value of thin-film- measuring instruments is well- known in industry, and many sectors of the economy depend on

accurate measurements. The in- tegrated circuit industry, for example, needs such instruments to evaluate and control oxidation or the deposition of metallic and di- electric films. The NBS instrument makes reliable measurements of commercially important films in in- tegrated circuits that are not ac- cessible to existing equipment.

19
Standing with their improved monochromatic

electron gun used in this surface science instrument are (from the left) Robert J. Celotta, Daniel

T. Pierce, and Charles S. Feigerle; co-winner

Alfred Seiler was not present.

Posing with their automated, high-precision ca- pacitance bridge are Robert D. Cutkosky (left) and Lai H. Lee.

Ronald W. Shideler is shown

with his parametric amplifier

electrometer.

High-Current Monochromatic Electron Gun

A team of NBS researchers earned an l-R 100 award for the development of a new type of monochromatic electron gun—

a

device to produce a beam of electrons—that is expected to have wide application in surface

science, electron spectroscopy,

and electron lithography.

Most electron guns make use

of a separate monochromator

stage to narrow the energy

spread of the electrons, but there

is a strict limit on the maximum

beam current that a monochromator can provide at any

given resolution. The new gun cir- cumvents these limits by making

use of a "negative electron affinity" (NEA) photocathode similar

to those used in night-vision de- vices to produce a high-current electron beam with a very narrow

distribution of electron energies.

The device has produced cur- rents in excess of 1 microamp

with an energy spread (FWHM) of 31 meV—five times better than

the closest competitive product.

The high-current monochromatic electron gun was de- veloped by Drs. Daniel T. Pierce,

Robert J. Celotta, Charles S. Feigerle, and Alfred Seiler of the NBS Center for Radiation Research.

Parametric Amplifier

Electrometer

Ronald W. Shideler, an electronics engineer in the NBS Center

for Analytical Chemistry, received

his award for inventing a device

designed to measure extremely

low levels of current through the computer-controlled data col- lection systems of mass

spectrometers.

The new electrometer is an im- provement over existing models

because of its ability to measure

signals at levels close to the theoretical limit of noise. It features

switch-selectable response times

so-the operator can control the

tradeoff between response time and noise level, two important

factors in performing a highly pre- cise and accurate mass spectrometric chemical analysis at low

levels (parts per million or lower). Though Shideler's invention was

designed for use with NBSdesigned thermal ionization mass

spectrometers, it may be used

with all similar types of instru- ments and measurement

systems.

Type 3 Capacitance

Bridge

Robert D. Cutkosky and Lai H. Lee of the NBS Center for Basic Standards earned an l-R 100

award for the design of an auto- mated, high-precision capacitance

bridge.

Capacitance bridges are used

in laboratories around the world

for calibrating standards of electrical capacitance. Their device, now called the NBS type 3 ca- pacitance bridge, is the first fully automatic capacitance bridge ca- pable of the precision and accuracy required by standards laboratories. It operates at a basic

Their device, now called

the NBS type 3 capacitance bridge, is the first fully automatic capacitance bridge capable of

the precision and accuracy required by standards laboratories.

accuracy 1,000 times better than

that of its closest competitor.

The type 3 capacitance bridge can select from and calibrate up

to 16 external capacitors with an

accuracy of 1 part per million and

20
a precision of 1 part per 100 million over a frequency range of 400 to 3000 Hz. At somewhat re- duced accuracy, it can cover a range from 20 to 20,000 Hz. Its greatest range of capacitance is 0 to 1200 picofarads; auxiliary

equipment may be added to ex- tend this range to 100

microfarads.

Error-Compensation

System for Computerized

Machine Tools

As part of their study of measure- ment and control systems for automation, NBS researchers in the Center for Manufacturing

Engineering developed a microcomputer-based error- compensation system for auto- mated machine tools that has

earned an l-R 100 award. Most computer numericalcontrolled (CNC) machine tools have software that automatically

corrects for some positioning er- rors caused by the tool's cutter path drive system. But such cor- rections only account for errors along "one degree of freedom,"

whereas a typical CNC machine

tool may have 20 or more de- grees of freedom that contribute

to geometric errors. The NBS

error-compensation system cal- culates the positioning error associated with a particular location of the cutting tool based on a prere- corded "error map" of static positioning errors. In addition, the temperature of various parts of the machine tool provides a key

to thermal positioning error. The

position of the tool's cutting edge

relative to the machine's coordinate system is provided by an

automatic tool-setting station which is part of the system. All three elements are used by the system to provide real-time error corrections. The system has been tested on

two different commercial machine

tools, in conjunction with two dif- ferent controllers, demonstrating

accuracy enhancements of 8 to 10 times over parts machined with out error compensation. It also makes it possible to eliminate the machine-tool warm-up period—up

to 10 hours of unproductive

operation —that was previously

required for precision machining.

The CNC machine tool error- compensation system was devel- oped by Kang Lee, Thomas

Charlton Jr., Dr. James Shaver,

Ralph Veale, and Bruce Bor- chardt of NBS, Dr. Alkan Donmez

and Professor Richard Liu of Pur- due University, and William Zinn

of Hardinge Brothers.

50-Kilohertz Phase Angle

Standard

Dr. Raymond S. Turgel, a physicist in the NBS Center for Electronics and Electrical Engineering, received an l-R 100 award for his development of a standard for phase meters that improves the speed of calibrations 10 times or more. This device is designed to ensure reliable measurements of phase in applications such as

testing aircraft navigational instru- ments, tracking satellites, and

checking the operation of electrical power lines. Turgel's invention works by cre- ating two precision sine waves

with frequencies from 2 Hz to 50

kHz, which are generated so the phase angle between them is known precisely and is adjustable

in steps of 0.002 degrees up to 5 kHz and in steps of 0.005 de- grees up to 50 kHz. Digital-toanalog converters are used to generate the analog output sig- nals, and the phase angle is de- termined from the sets of calculated values used for the digital signal synthesis, but is not de- pendent on reactive elements or frequency.

The microprocessor-based cali- bration standard is virtually drift

Pictured here from the left are Ralph C. Veale,

Bruce R. Borchardt, James R. Shaver, Alkan

Donmez, Thomas Charlton, Jr., and Kang B. Lee

who received an l-R 100 award for developing an advanced error-compensation system for

computerized machine tools. (Not present are C. Richard Liu and William Zinn.)

The development of an 50-

kilohertz phase angle standard by Raymond S. Turgel

merited an l-R 100 award.

free due to the inherent high stability of the device's crystal- controlled digital synthesis cir- cuitry. The digital synthesis

technology developed for the in- vention forms the basis for further developments in precision waveform generation.

21
t's an idea as old as the hills: Freezing preserves things.

Now scientists at the National Bureau of Standards are putting

this age-old chilling practice to use in the laboratory as they preserve hundreds of human

tissue and environmental speci- mens by freezing them at liquid nitrogen temperatures (about - 1 50 °C). The result is a "bank"

in which frozen "assets" (specimens) are deposited regularly

and withdrawn any time interest accumulates in a particular chemical element or pollutant

compound.

"The bank is especially valuable for determining pollutants

present in the environment at a

given place and time," says Dr. Stephen A. Wise, manager of the NBS specimen bank program. He

adds that by having a frozen specimen on hand—a human

liver donated from an autopsy, for example—scientists can analyze

the organ tissue and construct a "picture" of chemicals the person

had been exposed to until the time of death. The liver is a parti- cularly good indicator of individual exposure to pollutants because it acts as a sponge in which toxic

and beneficial —chemicals collect. The beauty of a cold storage

system like NBS' prototype speci- men bank is that if a new pollu- tant is discovered sometime in the future, specimens gathered

years before can be retrieved and

analyzed for this component.

Researchers then can establish a

"yardstick" that future analyses can be compared to, which would

indicate exposure to that pollutant across the population and over a

period of years. Depending on how long specimens had been

banked, it might even be possible

to determine exactly when and

where a particular pollutant entered the environment.

NBS has banked human livers

yearly since 1980 when its socalled Pilot National Environ- mental Specimen Bank was

launched in cooperation with the Environmental Protection Agency

(EPA). The Bureau gets its human

livers in 200-gram samples

about the size of a fist—from

autopsies conducted by state examiners' offices. Records about

the donor's sex, age, occupation,

and other factors are included whenever possible to give NBS

researchers clues about what to look for in chemical analyses. For example, if a person was a heavy

smoker, this will probably show

up in the liver's chemical

composition.

NBS has developed an elaborate protocol (procedure) for banking liver samples. It begins in

...if a new pollutant is discovered sometime in the

future, specimens gathered years before can be

retrieved and analyzed

for this component.

the autopsy room, where the more common stainless steel knife of the medical examiner is replaced with a special titanium

knife to minimize sample contamination. Livers are then placed

in Teflon bags, again to minimize

the contamination that could bias a chemical analysis, and shipped

to NBS at liquid nitrogen temperatures. Back in the lab, Bureau

scientists use a special "clean room" and Teflon containers to keep any outside impurities to a minimum.

Some aspects of the Bureau's

protocol were initially viewed with skepticism by other researchers,

says Wise. "We got a few laughs

from the scientific community in our early days when we insisted on the use of titanium knives and

Teflon containers. But we've

been so successful with these

materials, other scientists are

starting to use the same

approach."

As NBS researchers have analyzed the livers, they've noticed

certain trends. One of these is that environmental lead contamination appears to be declining. This study, however, is only in its early stages and re- quires further data before any firm conclusions can be made.

Another trend showed up in a recent study of 30 banked liver samples from a broad spectrum

of donors. NBS found traces of eight widely used pesticides, in- cluding the notorious DDT, in all the livers, leading Bureau re- searchers to speculate on just

where these materials came from. "We initially thought we'd find high levels of pesticides for our study in an older farmer who

might have been exposed to them over a number of years when his crops were sprayed,"

Wise says. "But we looked at a farmer's liver and his levels really weren't that high. So we suspect

that the reason all the livers have some degree of exposure is that the pesticides were absorbed

through the food chain." Wise

adds that though some pesticides

have been banned or restricted in this country, the same materials are still used on crops in some

foreign countries, and some of those foods are imported into the United States. Another part of the initial NBS/

EPA specimen bank project was

the storage of several thousand

marine mussels gathered from

the Narragansett Bay area of Rhode Island. Because mussels

collect impurities in the aquatic

environment, they are considered

good indicators of marine

pollution.

The NBS facility also is being

used as a repository for environ- mental samples taken from

coastal areas around the United

States. The National Oceanic and

Atmospheric Administration
(NOAA), which is examining marine pollution through the banking

of fish (croaker), mussels, and

sediment samples, has funded

NBS to develop protocols and to collect and bank some of the samples. One of the goals of the NOAA project, known as the National Status and Trends Pro- gram, is to establish a small bank

of "reference samples" at NBS

that can be compared for accuracy to those stored at NOAA's

own facility. Though the bulk of attention in the last 5 years has been on

banking and analyzing human and

marine samples, the NBS facility was also designed to store speci- mens that are environmental ac- cumulators of food and air pollut- ants. Milk and grain are typical indicators of food contaminants

and moss or lichen are good ab- sorbers of air pollution. Though

these samples have not been

banked yet, a new cooperative

program between NBS and

several other agencies has

opened the door to the banking

and analysis of food samples.

Dubbed the Coordinated Research Program on Human Daily

Dietary Intakes of Nutritionally Im- portant Trace Elements, the

project is a mammoth undertaking

to determine the constituents that make up typical meals in a world- wide cross section of countries. Bringing together NBS with the Department of Agriculture, the

U.S. Food and Drug Administration, and the International Atomic Energy Agency (based in Vienna, Austria), the program

aims to map what's good and bad

in the American diet and those of

11 other countries (Brazil, China,

Iran, Italy, West Germany, Sudan,

Turkey, Spain, Thailand, Canada,

and Sweden).

A typical day's meal including,

for example, a breakfast consisting of bacon, eggs, toast, and

coffee will be blended togetherhomogenized—and then analyzed

for chemical makeup," says Dr. Rolf Zeisler, an NBS chemist who

is a coordinator of the project.

Researchers will be looking for accurate levels of more than 20

nutritionally important elements, as well as for a few of the envi- ronmental pollutants that have

entered the food chain. NBS will contribute to the project by stor- ing some of the food samples in the specimen bank, by devel- oping protocols for handling and

homogenizing the food speci- mens, and by lending the expertise of its chemists to help an- alyze the samples. At a gathering

of the project participants earlier

this year, representatives agreed

that the program, among other

things, will result in confirmation

or revision of the Recommended

Daily Allowance (RDA) of various

nutrients—a list of numbers rep- resented on virtually every packaged food product sold in this country.

Other projects have been dis- cussed for the specimen bank,

such as storage of human ad- ipose (fat) tissue for EPA, which

is interested in levels of such

components as dioxins. NBS also

will be banking samples of human

blood serum to measure nutrients

in a program for the National Cancer Institute that aims to de- termine the role vitamins play in preventing tumors. And a pollu- tion study of the Chesapeake Bay

is in the early planning stages.

The NBS specimen bank is not the only one in the country. In fact, stored samples elsewhere

helped establish when the pesticide kepone first entered Vir- ginia's James River in the 1970's. A 1980 Canadian study used herring gull eggs banked for 9 years

to identify a decrease in dioxin

pollution in the Great Lakes. There also is a huge specimen

bank project under way in West

Germany, one that began about

Kathy Fitzpatrick (left) and Susan Stone load a human liver specimen into a liquid nitrogen stor- age tank.

the same time as the Bureau's. NBS and German scientists get

together regularly to compare

notes on their banking

experiences.

So while the specimen bank

idea is not a new one, the NBS

project was the first national pilot program with the goal of deter- mining the feasibility of such

banks and for establishing the elaborate protocols and handling

procedures for samples.

"One of the problems we had

when we started out," says Wise,

"was getting across the idea that the real benefits of banking speci- mens are way off in the future.

It's not something that has immediate results. But I think we've

shown that these facilities work. And while we'll probably always

serve as a facility for banking

mainly someone else's samples,

we're going to continue to refine our techniques and pass these

ideas on to other specimen bank

users."

by John Henkel

NBS Public Affairs Specialist

23
1

esearchers at the National Bu- reau of Standards have devel- oped a technique for observing

simultaneously—the magnetic

character of a surface and its physical structure over dimensions as small as 100 angstroms.

The new research tool is ex- pected to have important applications in a number of fields, includ- ing the development of high-density magnetic recording

media and small, high-efficiency

electric motors. It was designed

by Drs. John Unguris, Daniel

Pierce, and Robert Celotta of the NBS Center for Radiation Research and Dr. Gary Hembree of the NBS Center for Manufacturing

Engineering.

The technique weds an ultra- high-vacuum, high-resolution

scanning electron microscope

(SEM) with a new, compact elec- How polarization analysis works

Incident Electrons From

Scanning Electron Microscope y\ Spin Polarization / \ Analyzer

Spin-Polarized Secondary Electrons

Magnetization

A scanning-type electron microscope "scans" a

tightly focused beam of electrons across the

surface of the object under study. The actual

magnified image is derived from secondary elec- trons that are emitted from the object under the

action of this beam. The spin orientations of the

electrons in the original beam are random, but

the spins of the secondary electrons reflect those of the electrons in the surface being

probed. (The spins of the secondary electrons are in the opposite direction to the magnetization as a consequence of the mathematical defi- nition of magnetization.)

24

tron spin-polarization detector de- veloped at NBS. By measuring

the secondary electron spin polarization, the resulting instrument images directly the magnitude

and orientation of the magnetic

structure of materials with a resolution far better than the best cur- rent instruments, while simulta- neously producing a conventional SEM image of the surface. The magnetism of an object is essentially a measure of the net electron spin density in the material. Electron spins in non- magnetic materials have random

orientations; in materials with some degree of magnetism, more

spins are oriented in one direction than in the opposite direction

yielding an "electron spin

polarization." Not all of the electrons in a magnetic material are oriented in the same direction, however. Typically, the material contains re- gions or "domains" in which

there is a preferred direction along which the electron spins are oriented; the preferred direc- tions may vary from one domain

to another. An important feature

of this new technique is that, since the SEM beam probes re- gions smaller than the domain

size, it is possible to view the magnetic domains with very high

spatial resolution. Exactly how the domains are magnetized and what relationship the surface topographic and

chemical features bear toward

the arrangement and distribution of the surface magnetic domains

are key factors in a number of important magnetic materials. Examples include high-density

magnetic recording media for computers; new, strongly magnetic alloys for use in small, highefficiency electric motors; and

communications devices. A key element in the new NBS

instrument is a low-voltage elec- tron spin detector. Previous spin detectors (Mott detectors) operate at about 100,000 volts and reShown are magnetic domains

imaged using an SEM fitted with the NBS electron spinpolarization analyzers. The

light and dark regions corre- spond to areas of opposite

magnetization. The material

is an Fe-Si 3 percent single

crystal and the picture dimensions are about 50 micrometers

by 50 micrometers.

quire at least a cubic meter of space and special high-voltage

precautions. The new detectors,

which operate at about 150 volts,

will fit in a cube about 6 cm on a

side and are at least as efficient as an optimized Mott detector. The detector relies on the spindependent scattering of the elec- trons from an evaporated polycrystalline gold film. The polarized SEM is based on

research results reported by NBS

in 1982 which demonstrated that the secondary electrons which

are emitted by targets struck by an electron beam retain the

spin polarization of the region of the surface from which they originate.

NBS would like to set up col- laborative research programs with

industrial and academic labs to exploit the potential of this new

instrument. Interested researchers are invited to contact Dr. Robert Celotta, B206 Metrology

Building, National Bureau of Standards, Gaithersburg, MD 20899,

301/921-2051 for further information.

by Michael Baum

NBS Public Affairs Specialist
Open Sy

nee the excavators, the bricklayers, and the carpenters are fin- ished, they leave behind a framework. Then come the plasterers, the finishers, and the decorators,

and they turn the framework into a house.

Likewise, once the designers of a computer system, or an entire network, have put in place the hardware and procedures—the framework—needed to permit one part to talk to another part, the software people have to give the system something to say.

Structure and Function

The makers of a house or other mechanical/electrical system can

rely on standards, both formal and informal —standard materials, standard design specifications, standard procedures—to help

them with both structure and

function. But when it comes to computer systems, until very re- cently builders have had to go it alone, from cutting and sizing the lumber to figuring out how to drive each nail. That's not very

efficient. And that's why standards for networking and software, the

structural and functional aspects

of integrated computer systems,

are high on the Most Wanted List of three sets of people: systems

builders, like Boeing and TRW,

who assemble integrated and em- bedded computer systems; major

vendors of computer equipment

and software; and large-scale

computer users, like the U.S. gov- ernment. Successful network and

software standardization will re- sult in "open" systems, that is, computer systems which can be

used to exchange information worldwide to facilitate daily commerce.

"The systems builders may

build multimillion-dollar systems,

like a space shuttle, and the hard- ware and software get very complicated very quickly," explains

Helen Wood, head of the National Bureau of Standards' Infor- mation Systems Engineering Di- vision. "They need to solve complex problems, but like many

computer users, they're faced

with the need to use equipment

from one manufacturer that may

be the best hardware solution for the problem, but it won't talk to another piece of equipment made

by somebody else. Then, they

have to have software for, say,

...the Bureau's computer

institute "is uniquely situated to be an effective,

impartial negotiator in the

standards development

process."

navigation, but it won't talk to the software that handles engineseparation systems."

In other words, compatibility, or the lack of it, is two-tiered: It is lo- cated in both the structural tier and the functional tier of the sys- tem. Helen Wood's concern is functional compatibility, the software.* NBS Standards Not

Regulatory

Wood, as a manager in the NBS

Institute for Computer Sciences

and Technology (ICST), directly

represents the federal govern- ment's interests, as a major user

of computer systems, in computer-standards development.

ICST is empowered by Congress

to develop Federal Information Processing Standards, called FIPS, and guidelines for use by

' Others at NBS are concerned with structural compatibility. See NBS Research

Reports on computer networking stan- dards, called "Welcome to the New Computer Age: The Era of Networks," published in February 1985.

government agencies in planning,

purchasing, and using computer

systems. Wood stresses, "We

strive to ensure that FIPS are consistent with voluntary national and international standards wherever possible."

The Bureau's success in getting industry to support its computer standards comes not from

regulatory powers, which it does

not have, but from two other factors: the collective clout of federal purchasing power—government

agencies spend some S14 billion a year on computers and related equipment and services —and

NBS' "leveraged" position in the computer community.

Vico Henriques, president of the Computer and Business

Equipment Manufacturers Association, recently described this position for Congress. Henriques told members of a Senate subcommittee in March that NBS has expertise and facilities for standards development unmatched else- where in the world; that unlike a company with proprietary self- interests, NBS' impartiality can

be—and is —trusted; and that, therefore, the Bureau's computer

institute "is uniquely situated to be an effective, impartial negotiator in the standards devel- opment process. It promotes vol- untary international standards that preserve U.S. industry's competitive positions in the world

market, while supporting users' needs for standards to achieve

increased productivity and deliv- ery of services at reduced cost." NBS Aims: Increased

Productivity, Reduced

Cost

NBS' Helen Wood stresses that software standards can mean

productivity gains and cost savings to government computer us- ers and to the entire computer

community of systems builders,

25
Charles Sheppard, a manger in the NBS computer-graphics area, and summer student Bill Youstra (standing) watch as Ray Youstra, also a student, works with the NBS-developed

logical database design graphics model.

vendors, and users. "Our data- base management standards

alone are expected to save the government some $265 million," she says. "But I'm not talking

about standardizing proprietary

products," she hastens to add.

"I'm talking standards for assuring that every database program

can carry out essential functions and standards for easing integration between one program and

another."

26

In other words, to save time and greatly increase the effi- ciency of human and machine,

both data and trained users should be "portable" from one

database management system to another and conversion from one

such system to another should be

easy. Wood explains: "Database

management systems are pro- grams that define data by classi- fying them and manage data by

storing, recalling, and analyzing

them. When you ask the same

question on two different DBMS's, against the same col- lection of data, you want to get the same answer. If those two DBMS's say they conform to the same standard, that should be

your guarantee that you will get

the same answer.

"Just think. You don't have to

limit yourself to using a single

program or set of programs or even a certain kind of hardware if you have a standard that is widely used. And think of the time and
money to be saved in training.

You should be able to do the same standard operations with

different software and hardware

systems without retraining."

The same sorts of benefits will accrue from the use of standardized approaches to computer

graphics, Wood claims. But not

yet, in either case. Software inte- gration is presently accomplished

only by expensive ad hoc pro- gramming efforts, unless a piece

of software is part of a proprietary

system of integrated programs.

"But in 5 years we should see open systems in all kinds of soft- ware," Wood claims. The Bureau is working to make

this expectation a reality, particularly for data management and

graphics systems. Standards activities currently focus on stan- dard programming-language for- mats for specifying essential data

structures and operations; stan- dard data-description formats into which data structured in proprietary formats can be converted

for transfer to other systems; a standard Data Dictionary System

which specifies the most commonly needed facilities of sys- tems used to describe and define

data; and graphics programming

standards.* Wood points with pride to suc- cesses in each of these areas. "We are particularly pleased with the collaborative work we do with the NBS Automated Manufacturing Research Facility

[AMRF] where we can per- formance test our standards and

work with them on specific data management and graphics

needs," she says. The AMRF is

* A complementary standards activity else- where at NBS involves the Initial Graphics

Exchange Specification, or iGES. IGES

provides a format for the 3-dimensional

parts models typical of computer-aided

design systems. It can be used in conjunction with the standards described in this article.

the Bureau's automated flexible manufacturing facility —a research

center for studying the computercontrolled machine shop. Researchers are developing modular

control systems that can use the same database to accomplish dif- ferent tasks via programmable ro- bots. It is an effort to produce an

efficient standard control struc- ture for flexible automated manufacturing systems of virtually any

type, differences in proprietary

hardware and software

notwithstanding.

The Information Systems Engineering Division and AMRF are

also collaborating on a Defense

Department (DOD) project, Wood

says: "Neither of us could do it alone. It is just a single instance

"Our database management standards alone are expected to save the

government some $265

million."

of the pressing overall need for open-systems software and hard- ware. What DOD needs is a computer-aided logistics support

system. In other words, how do

you move people, supplies, and

equipment around, keep track of

all of it, and manage it all at the same time? That's what they

want to know. If something

breaks, for example, how does

somebody find out how to fix it? Manuals go out of date and must

be updated. That's a lengthy pro- cess. What if, instead, all the in- formation is in computerized form

and instantly available. A change

in a manual, or any other change,

would reverberate through the system immediately. We're working on that project right now."

As Wood emphasizes, NBS is responsible not only for standards

but also for the supporting test methods. "Test methods are needed both during development

of standards and to prove product

conformance once standards are

in use," she says. "That means

you have to develop a testing

program that puts a software package through its 'standard' paces. We're doing that for both data dictionaries and graphics

programming software."

Data Dictionary

David Jefferson manages the NBS database standards pro- grams, including the data dictio- nary standard. "A database man- agement system can support

many different applications, like payroll systems, accounting sys- tems, and so on," he says. "Often those applications have to be

specially programmed [they aren't bought off-the-shelf]. So, you

need a source of information for controlling all the steps in producing and using a database application. A data dictionary is that control. It defines the terms used in a database system, like record, or

set, or price, or whatever, and the semantic relationships among

them.

"Also, like a real dictionary, it may give you synonyms and a

textual explanation of what things mean. Or it may only give you a

very basic meaning. For example,

it may only tell you that a Social Security number is nine digits

and nothing about what it's for or how it's used. But it may also give several definitions for price, such

as base price, sales price, and

the like. You see, one of its major

tasks is to facilitate the use of very precise data among people. This function also resolves conflicts between two programs that use different definitions for the same terms." Another function of a data dic- tionary, Jefferson explains, is a di- rectory function. "This tells you

that a record or whatever is in a

particular place and instructs you

how to get it. When you're

searching for something, this
NBS Wants Software Companies

for Testing Program

Participation Will Help Companies Develop

Standard Software Products

Producers of computer soft- ware are invited to join other software companies and the National Bureau of Standards

in software-testing programs

related to emerging national and international software

standards. The accompanying article reports on developments at NBS in computer software

standards, particularly those

for data dictionary systems

and computer graphics. These

and other standards activities

in the areas of database man- agement systems, pro- gramming languages, operating systems, and document

interchange are complemented

by NBS programs for testing

standardized software.

The testing programs aim at providing techniques that can

ultimately be used in private laboratories to determine

whether a specific software product conforms to a particular software standard. Participating companies will work

with NBS researchers to design, develop, and evaluate

test procedures. NBS will pro- vide available documentation,

prototype implementations,

and laboratory testbeds. For information on how to participate in one or more of these programs, write or call Helen Wood, A255 Technology Building, National Bureau of Standards,

Gaithersburg, MD 20899,

301/921-3553.

saves time. And it can do other

things. It can tell you how data in- teract with other things. Say you

have several zip-code-using pro- grams, like a personnel data sys- tem and a payroll system and

whatever. A data dictionary can

tell you what programs and what

files contain zip codes, so if you

need to change zip codes, you

know where to go. In fact, it can

inventory an entire information re- source, including files, programs,

and hardware."

A data dictionary isn't just a passive tool either. It can limit ac- cess to programs and files. This

function is of major importance,

whether the data in question are

sensitive, as in programs related

to national security, or simply pri- vate, as in medical records. Over the past 3 years, NBS has

worked with computer users and

vendors to develop a standard for a Data Dictionary System; the DDS is now a draft FIPS standard

containing specifications for selecting, evaluating, and procuring data dictionary software. Software

which satisfies the standard will make the contents of database

systems more portable, from pro- gram to program and from one

piece of hardware to another. It will also make skills more portable, because computer personnel- will not have to learn a new

language and procedure every

time they use a different piece of data dictionary software. Such

portability is expected to save the government more than $135

million* over the first 5-6 years of use.The NBS Data Dictionary System has been adopted by The

American National Standards

Institute (ANSI) as the basis for a proposed national standard. In addition, the International Organization for Standardization

(ISO) is considering these specifi- cations as an international stan- dard. One research associate from industry is already at work

helping NBS design and develop

conformance tests for the pro- posed DDS standard (see box).

Computer Graphics

In the NBS Information Systems

Engineering Division, Mark Skall manages the work in graphics

standards. He says his group be- gan a study in June 1983 to find out what federal agencies were

doing as far as the use of computer graphics is concerned and

to determine what they needed

for understanding how to buy and

use graphics programs. As a re- sult of the study, NBS is pursuing

the development of several graphics standards and is working on related conformance testing

and measurement techniques for graphics software. The study revealed a particular

need for a programming standard

for 2-dimensional graphics. Agencies were using different packages to write graphics applications and when they tried to exchange applications, they had

This amount is part of the $265 million mentioned earlier.
to reprogram. Programmers

wanted a 2-dimensional graphics standard for producing portable

graphics applications. Computer

users in the government also wanted to be able to transfer just

pictures, rather than whole

programs.

The first need can be satisfied by an ANSI and ISO proposed

standard known as the Graphical

Kernel System (GKS), which was

developed originally by the GMD,

a German government organization. It is being processed

by ICST as a FIPS. The need for picture transfer will be met by a standard called Computer Graphics Metafile, also being developed

in ANSI and ISO. It, too, is being

processed as a FIPS. NBS has been instrumental in fine-tuning these and other national and international graphics

standards to make them fully functional. For example, in regard

to GKS, "what was missing was a standard way to access graphic

functions from different pro- gramming languages," Skall says. "So I chaired an ANSI subcommittee that developed bindings to the graphics systems from differ- ent programming languages. We

picked the languages most re- quested by the computer users we surveyed. They named FORTRAN, C, PASCAL, and ADA.

The technique we produced is the same for every language, so if someone is trained to use the graphics standard with FORTRAN, his skill is transferable to the other languages."

Additional ANSI/ISO graphics

standards under development,

with NBS support, are a standard

for 3-dimensional graphic functions and a computer graphics in- terface for hardware and soft- ware. ICST intends to process

these standards as FIPS when

they are completed.

Other projects include work

with industry to get the standards

into off-the-shelf products and to develop tests for conformance to the standards. Skall's group is setting up a comprehensive

graphics laboratory for the devel- opment and use of effective test- ing techniques. They have also signed an agreement with the GMD to coordinate U.S. evaluation of the GKS conformance

tests under development in Europe.

Wood says the key feature of NBS' approach to software stan- dards is interaction—interaction with the government community

the computer institute serves,

interaction with domestic computerrelated corporations, and inter- action with the national and inter- national standards-making

community.

"We welcome cooperative re- search efforts with American

Flanking Helen Wood in this picture are Patricia

Konig and Dr. Alan Goldfine, the NBS researchers most directly involved with the NBS data

dictionary system.

companies through such mechanisms as the NBS Research Associate Program, and we bring in standards expertise through the Guest Worker Program," she

says. "We want to see standards used to enhance fair competition

in computer software worldwide.

Right now this country produces

70 percent of the world's soft- ware. Other countries will naturally take a bigger share of that market in the future. But we don't want to lose our competitive edge

by turning our backs on standards

while other nations forge ahead.

We must stay in front in the stan- dards game." J.C.

29
NEW PUBLICATIONS

HELP IN DESIGNING DATABASES

Fong, E.N., Henderson, M.W., Jefferson,

D.K., et al., Guide on Logical Database

Design, Natl. Bur. Stand. (U.S.), NBS

Spec. Pub. 500- 122, 1 15 pages (Febru- ary 1985). Order by stock no. 003-003-02631-0 from GPO, $4.50

prepaid.

An information system is only as good as

the database which supports it; a poorlydesigned database can lead to time- consuming and expensive software re- visions as needs change. To help avoid

this, NBS has developed a guide to en- able managers, systems analysts, and

applications programmers to plan for an

information system that will fulfill both present and future needs. This publication suggests that a database be de- signed in four phases during which all the subsystems within the system, the data flows, data structures, and user needs are described. The guide is in- tended to help design very large, complex information systems which are meant to be used for a long time.

FIELD STRENGTHS IN COMPLEX

ENVIRONMENTS

Kanda, M., Randa, J., and Nahman, N.S., Possible Estimation Methodologies for Electromagnetic Field Distributions in Complex Environments, Natl. Bur. Stand. (U.S.), NBS Tech. Note 1081, 52

pages (March 1985). Order by stock no. 003-003-02638-7 from GPO, $2 prepaid.

Electromagnetic (EM) pollution is a fact

of life today; there is a complex matrix of electronic equipment operating in a complex EM environment. As a result, the es- timation of the maximum EM field strength in a given area is very important

in addressing many interference problems such as the penetration of EM

waves into buildings that house sensitive electronic and ordnance equipment. This

report outlines three approaches to esti- mating EM field distributions in complex

environments: 1) statistical treatment of the spatial distribution of EM field in- tensities; 2) a numerical computation using a finite-element form of the EM action functional; and 3) use of a directional probe to scan a volume.

30

GUIDE TO IMPROVED QUALITY

ASSURANCE

Taylor, J.K., Principles of Quality As- surance of Chemical Measurements,

Natl. Bur. Stand. (U.S.), NBSIR 85-3105,

80 pages (February 1985). Order by

stock no. PB 85- 177947/AS from NTIS, 511.50 prepaid.

This NBS report should help researchers and technicians interested in bettering the precision and accuracy of analytical

chemical measurements—such as those needed in the compositional analysis of materials, process control, and regulatory

enforcement. The publication is a con- densed version of seminars NBS offers chemists, lab supervisors, and quality control professionals in the quality assur- ance (QA) of chemical measurements.

Included are discussions of what QA is, quality control techniques, control charts,

sampling methods, QA programs, protocols, and functions of a reference laboratory. For more information about NBS

quality assurance seminars, contact Dr. John K. Taylor, 301/921-3497.

COMPUTER-AIDED DISPATCH

SYSTEMS

Brenner, D.J. and Cadoff, M.A., Guide to Computer-Aided Dispatch Systems,

Natl. Bur. Stand. (U.S.), NBSIR 84-2991,

42 pages (March 1985). Order by stock

no. PB 85-187565/AS from NT/S, $8.50

(microfiche, $4.50) prepaid.

The NBS Law Enforcement Standards

Laboratory has developed a "user's guide" for public-safety agencies and

other organizations interested in buying

or improving a computer-aided dispatch

(CAD) system. CAD systems support dis- patchers by providing an efficient system

for responding to a citizen's complaint

and tracking the progress of the re- sponding units. Use of a CAD system im- proves the accuracy of information trans- mitted to the patrol officer and provides

automatic database checks (crosschecks on location of incidents, for ex- ample), record-keeping, and reportgeneration. Prepared for the National

Institute of Justice, the NBS guide dis- cusses CAD system operation, hardware

and software components, CAD system

benefits, maintenance and repair, and

the procurement process.

NEW ADDITION TO OPTICAL RADIATION SELF-STUDY MANUAL

Nicodemus, F.E., editor, Self-Study

Manual on Optical Radiation Measurements: Part 1—Concepts, Chapter

12, Natl. Bur. Stand. (U.S.), NBS Tech. Note 910-8, 44 pages (April 1985). Order

by stock no. 003-003-02647-6 from GPO,

$2 prepaid.

NBS has published another section of

this manual, a long-term project to pro- duce a comprehensive guide to the the- ory and practice of making accurate measurements of optical radiation. The new section, "Chapter 12, Blackbodies,

Blackbody Radiation, and Temperature

Scales," by Joseph Richmond and Fred Nicodemus deals with the role of temperature in optical radiation measurements. This is the eighth volume in the Self-Study Manual series. Previous volumes examine a variety of topics in the basic measurement theory of optical

radiometry, the calibration of radiometric instruments, and the specific application

of that theory to some important solar irradiance measurements.

PERFORMANCE OF OSI TRANSPORT

PROCEDURES

Mills, K.L., Gura, J.W., and Chernick,

CM., Performance Measurements of

OSI Class 4 Transport Implementations, Natl. Bur. Stand. (U.S.), NBSIR 85-3104, 52 pages (January

1985). Order by stock no. PB

85- 177657/AS from NT/S, $10 prepaid.

The NBS Institute for Computer Sciences

and Technology has developed a system

to measure whether computer equipment

incorporating the transport protocol layer of the Open Systems Interconnection

(OSI) Reference Model is performing ac- cording to the standards that have been

developed by the International Or- ganization for Standardization. The OSI

Reference Model is a blueprint to make

possible computer-to-computer communication. The transport protocol carries out the data communications function of assuring that data are not lost, duplicated, or corrupted in transit and that they get to their destination in the right order. This report describes the system

and the measurements it can make.
CERTIFICATION PROCEDURES FOR

STATE LABS

Oppermann, H.V. and Taylor, J.K., State Weights and Measures Laboratories,

Natl. Bur. Stand. (U.S.), NBS Hdbk. 143,

82 pages (February 1985). Order from

Office of Weights and Measures, A617

Administration Building, National Bureau

of Standards, Gaithersburg, MD 20899,

301/921-2401.

This publication describes for industrial users of measurement laboratory ser- vices, including nuclear power plant operators and others, the procedures fol- lowed by NBS in certifying state weights

and measures laboratories. A certified laboratory must satisfy general and specific requirements for each competence

area. Competence includes a laboratory's management practices, test pro- cedures, and the facilities that are avail- able for performing reliable measurements, principally mass, volume, and

length. This handbook contains pro- cedures for authorizing certified laboratories to conduct evaluations of weighing

and measuring devices and systems un- der the National Type Evaluation Pro- gram (NTEP), a one-time evaluation for new measuring devices. Under NTEP,

NBS or one of the authorized state laboratories performs an evaluation for ac- ceptance by all of the other states, thereby eliminating costly duplicate tests by each jurisdiction.

ASSESSMENT OF NUCLEAR POWER

INDUSTRY'S MATERIALS DATA

NEEDS

Rumble, Jr., J.R. and Westbrook, J.H. (General Electric Corporation), Computerizing Materials Data—A Workshop

for the Nuclear Power Industry, Natl. Bur. Stand. (U.S.), NBS Spec. Pub. 689,

44 pages (January 1985). Order from Dr. John R. Rumble, Office of Standard Ref- erence Data, A323 Physics Building, National Bureau of Standards,

Gaithersburg, MD 20899, 301/921-3441.

Designers and engineers for the nuclear power industry, which has more than a $100 billion investment in materials, are concerned about the retrofitting of exist- ing facilities and extending the service

life of materials that are in place. This

publication reports on the conclusions

and recommendations by participants at a special meeting sponsored by NBS, the Metal Properties Council, and other leading industry groups. Participants were

asked to identify the types of materials property data that are needed and to de- termine how they will be used. The infor- mation was sought to help develop the National Materials Property Data Net- work, a joint industry/government effort to come up with a computerized "gateway" system for fast and easy access to various databases of validated data on

the engineering properties of materials.

ANNUAL DIRECTORY OF ACCREDITED LABORATORIES

Berger, H.W., editor, 1984 NVLAP Directory of Accredited Laboratories, Natl. Bur. Stand. (U.S.), NBS Spec. Pub. 687,

79 pages (February 1985). Order from

Harvey Berger, Associate Manager, Laboratory Accreditation, A531 Administration Building, National Bureau of Standards, Gaithersburg, MD 20899,

301/921-3431.

The eighth annual directory from the National Voluntary Laboratory Accreditation Program (NVLAP) lists approximately 120

laboratories nationwide that are accredited in one or more areas of testing. It in- cludes a report on current program activities and the new NVLAP program

procedures adopted in late 1984 to in- crease efficiency and reduce costs. Currently, there are voluntary laboratory accreditation programs for thermal

insulation, ready-mixed field concrete,

carpet, solid-fuel room heaters, acoustical testing services, personnel radiation dosimeters, commercial products (paper

and paper products, paints and related coatings and materials, and mattresses),

and photographic film.

FORECAST OF TELECOMMUNICATIONS TECHNOLOGY

Kay, P. and Powell, P., editors, Future

Information Technology— 1984 Tele- communications, Natl. Bur. Stand.

(U.S.), NBS Spec. Pub. 500-119, 337

pages (December 1984). Order by stock

no. 003-003-02626-3 from GPO, $9.50

prepaid.

Telecommunications technology is the focus of this report, compiled and edited by NBS. It includes a telecommunications forecast through 1999, three per- spectives on the divestiture of AT&T, a discussion of how changing technology

will affect computer security, and how

management will be affected by trends in information technology. The report also summarizes an industry workshop held in September 1984 at NBS that discussed

trends in telecommunications technology.

DIRECTORY OF CERTIFIED STATE

WEIGHTS AND MEASURES

Oppermann, H.V., State Weights and

Measures Laboratories—Program Description and Directory, Natl. Bur. Stand. (U.S.), NBS Spec. Pub. 686, 69

pages (January 1985). Order by stock

no. PB 85-137651 from NTIS, $10

prepaid.

Defense contractors, pharmaceutical

manufacturers, nuclear power plant operators, food processors, petroleum distrib- utors, and others who must verify that

their measurements standards are trace- able to NBS will be interested in the new

directory of state weights and measures

laboratories that are certified by the Bureau. As a part of its mission to promote

uniform standards of measurement, NBS

trains state metrologists in test pro- cedures used in NBS laboratories and

conducts a voluntary certification pro- gram for state laboratories. The directory

is in two parts: Part I describes certified areas of measurement and requirements

for laboratory certification; Part II lists state measurement laboratories and the services they provide to state and local weights and measures agencies, as well as those that are available to industry.

ORDERING INFORMATION

To order publications from NTIS, send

request with payment to: National Technical Information Service, Springfield, VA

22161. Publications can be ordered from

GPO by mailing order with payment to: Superintendent of Documents, U.S. Government Printing Office, Washington, DC

20402. 0
CONFERENCE CALENDAR

Workshop on Electrical Measurement

Assurance, Ramada Hotel O'Hare,

Rosemont, IL October 27-November 1, 1985

This intensive 5-day workshop will pro- vide in-depth training for those involved

in d.c. and low-frequency electrical measurements. Participants will receive in- struction based on techniques used in the Electricity and Statistical Engineering

Divisions of NBS. The objective will be

an understanding by participants of how

to establish and maintain rigorous quality control programs in their own laboratories to ensure the accuracy of electrical measurements. Sponsored by NBS. Contact: Dr. Arthur McCoubrey, B160 Physics

Building, NBS, Gaithersburg, MD 20899,

301/921-3301.

Factory Standards Conference, NBS,

Gaithersburg, MD

November 20-21, 1985

Individuals from universities, research

laboratories, and industrial organizations

will discuss the issues associated with the design and implementation of factory

models for automated manufacturing sys- tems. In addition, attempts will be made

to identify potential areas for standardization for these systems. A test run of the Automated Manufacturing Research

Facility will be held in conjunction with the meeting to demonstrate the capabilities of this manufacturing research test- bed. Sponsored by NBS. Contact: Dr. Albert Jones, A127 Metrology

Building, NBS, Gaithersburg, MD 20899,

301/921-2461.

Workshop on Test Procedures for Precision Instrumentation and ATE

Systems, NBS, Gaithersburg, MD

November 5-6, 1985

At this workshop, researchers, users, manufacturers, testing companies, and

calibration laboratories will exchange in- formation on the procedures used in test- ing the performance of precision instru- mentation and ATE systems. Topics to be discussed include first article/ acceptance testing, bid sample testing,

maintenance/calibration testing, test ac- curacy ratios, economic tradeoffs of testing, case histories of specific test pro- grams, optimum calibration strategies,

and recommended practices. Sponsored

by the Institute of Electrical and Electronics Engineers and NBS. Contact: John R. Sorrells or Barry A. Bell, B162 Metrology

Building, NBS, Gaithersburg, MD 20899,

301/921-2727.

Power Semiconductor Devices Workshop, NBS, Gaithersburg, MD

December 5, 1985

Designed for professionals actively working in the field of power semiconductor

devices, this workshop will be held in conjunction with the 1985 IEEE Inter- national Electron Devices Meeting in Washington, D.C. All attendees will be

expected to be active participants and come prepared to help develop re- sponses to specific questions that will address particular topic areas. Sponsored by NBS and the Institute of Electrical and Electronics Engineers Electron Devices Society. Contact: David L. Blackburn, B310 Technology Building,

NBS, Gaithersburg, MD 20899,

301/921-3621 or Sandy Kelley, B344

Technology Building, NBS, Gaithersburg,

MD 20899, 301/921-3541.

Workshop on Measurement of Electrical Quantities in Pulse Power

Systems—II, NBS, Gaithersburg, MD

March 5-7, 1986

The purpose of this workshop is to dis- seminate information on modern measurement techniques, define the state-of- the-art of measurement of electrical quantities in pulse power systems, and

identify areas in which improvements in measurements are required. Papers will be presented on voltage, current, power, and energy measurements; data acquisition and processing; and calibration methods for laboratory and machine use. Organized by NBS. Contact: John R.

Sorrells, B162 Metrology Building, NBS,

Gaithersburg, MD 20899, 301/921-2727

or Dr. Ronald H. McKnight, B344

Metrology Building, NBS, Gaithersburg,

MD 20899, 301/921-3121.

CPEM 86, NBS, Gaithersburg, MD

June 23-27, 1986

CPEM 86 is the world's premier inter- national conference for those in the

fields of electromagnetic metrology and

related fundamental physical constants. Papers describing original work, not pre- viously published or presented, covering

the theory, design, performance, simulation, or application of electromagnetic

standards, measurements, techniques,

instruments, or systems, are sought. The

following fields are considered to be especially appropriate: EM-related funda- mental constants and standards; direct current, low frequency, and RF; time,

time-interval, and frequency; antennae and fields; microwaves and millimeter waves; infrared, visible, and ultraviolet radiation; lasers; electro and fiber optics;

cryo-electronics; automated measurements; and technical calibration ser- vices. Sponsored by the Conference on

Precision Electromagnetic Measurements. Contact: Norman Belecki,

B146 Metrology Building, NBS, Gai- thersburg, MD 20899, 301/921-2715.

32
TWm he National Bureau of Standards was established by an act of Congress on March 3, 1901. The Bureau's overall goal

is to strengthen and advance the nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the nation's physical measurement system; (2) scientific and technological services for industry and government; (3) a technical basis for equity in trade; and (4) technical services to promote public safety. The Bureau's technical work is performed by the National Measurement Laboratory, the

National Engineering Laboratory, the Institute for Computer Sciences and Technology, and the Institute for Materials Sci- ence and Engineering.

THE NATIONAL MEASUREMENT

LABORATORY

Provides the national system of physical

and chemical measurement; coordinates

the system with measurement systems of other nations and furnishes essential ser- vices leading to accurate and uniform

physical and chemical measurement

throughout the nation's scientific community, industry, and commerce; provides

advisory and research services to other government agencies; conducts physical

and chemical research; develops, pro- duces, and distributes Standard Refer- ence Materials; and provides calibration services. The laboratory consists of the

following areas:

• Standard Reference Data

• Measurement Services

• Basic Standards

• Radiation Research

• Chemical Physics

• Analytical Chemistry

THE NATIONAL ENGINEERING

LABORATORY

Provides technology and technical ser- vices to the public and private sectors to address national needs and to solve national problems; conducts research in engineering and applied science in support

of these efforts; builds and maintains competence in the necessary disciplines

required to carry out this research and

technical service; develops engineering

data and measurement capabilities; pro- vides engineering measurement traceability services; develops test methods

and proposes engineering standards and

code changes; develops and proposes new engineering practices; and develops

and improves mechanisms to transfer re- sults of its research to the ultimate user. The laboratory consists of the following centers:

• Applied Mathematics

• Electronics and Electrical Engineering

• Manufacturing Engineering

• Building Technology

• Fire Research

• Chemical Engineering

THE INSTITUTE FOR COMPUTER

SCIENCES AND TECHNOLOGY

Conducts research and provides sci- entific and technical services to aid federal agencies in the selection, acquisition, application, and use of computer

technology to improve effectiveness and

economy in government operations in ac- cordance with Public Law 89-306 (40 U.S.C. 759), relevant Executive Orders,

and other directives; carries out this mission by managing the Federal Information Processing Standards Program, de- veloping federal ADP standards

guidelines, and managing federal participation in ADP voluntary standardization activities; provides scientific and

technological advisory services and assistance to federal agencies; and pro- vides the technical foundation for computer-related policies of the federal government. The institute consists of the

following centers:

• Programming Science and Technology

• Computer Systems Engineering

THE INSTITUTE FOR MATERIALS

SCIENCE AND ENGINEERING

Conducts research and provides measurements, data, standards, reference

materials, quantitative understanding,

and other technical information funda- mental to the processing, structure, properties, and performance of materials; ad- dresses the scientific basis for new

advanced materials technologies; plans research around cross-country scientific themes such as nondestructive evaluation and phase diagram development; oversees Bureau-wide technical pro- grams in nuclear reactor radiation re- search and nondestructive evaluation;

and broadly disseminates generic technical information resulting from its pro- grams. The institute consists of the fol- lowing divisions:

• Nondestructive Evaluation

• Inorganic Materials

• Fracture and Deformation

• Polymers

• Metallurgy

• Reactor Radiation
U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Gaithersburg, MD 20899

OFFICIAL BUSINESS

Penalty for Private Use, $300

BULK RATE

POSTAGE & FEES PAID NBS

PERMIT No G195