NATIONAL INSTITUTE OF STANDARDS &

TECHNOLOGY

Re^^di Mmmtim Center

^Msersborg, MD

On the cover: NIST materials research

engineer Wen Tseng uses molecular

beam epitaxy to grow and study the

properties of thin films of semiconductor compounds such as gallium

arsenide and aluminum gallium

arsenide. For more on NIST semiconductor research, see the article on page 18.
Research Reports

U.S. DEPARTMENT OF COMMERCE

Robert A. Mosbacher, Secretary

National Institute of Standards and Tecfinology

Jotin W. Lyons, Director

National Institute of Standards and Tectinology

Gaittiersburg, MD 20899

301/975-2000

Boulder, CO 80303

303/497-3000

May 1990

NIST Special Publication 783

Prepared by the Public Affairs Division A903 Administration Building

National Institute of Standards and Tecfinology

Gaittiersburg, MD 20899

301/975-2762

Any mention of commercial products

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

by the National Institute of Standards and Technology nor does It imply that the products mentioned are necessarily

the best available for the purpose.

Research Update

Lyons New Head of NIST 5

President Seeks Boost for NIST in '91 9

Looking for 'Good' Vibrations 11

Milestone: 500 Very Good Ideas 14

Measuring in the Lilliputian World of Semiconductors 16

Loma Prieta: A Primer for Public Policy 21

More Than Just for Safety's Sake 24

Stress and Strain on the Railroad Train 28

New Publications 30

Conference Calendar 32
Research Update

Calibrating tlie Space Telescope

NIST researchers provided a suite of

state-of-the-art radiometric calibrations

for the Hubble Space Telescope (HST).

Because everything discovered by

astronomy depends on analyzing light

from distant stars and exotic objects, ex- tremely accurate instrument calibrations are essential to the space telescope mission. NIST scientists aided in the design

of a special optical simulator to test the

HST faint object spectrograph and cali- brated the simulator for brightness. They

then calibrated the special light sources used to test the overall sensitivity of the

telescope's optics and measuring instru- ments. In addition, the researchers pro- vided special wavelength and brightness

calibrations for an on-board standard

lamp, part of the HST high-resolution

spectrograph. The latter will make it possible to identify the particular element

associated with individual spectral lines,

to estimate the speed of the element to

within a kilometer per second, and to ac- count for any changes in instrument cali- brations while in space. NIST is the only source in the world for radiometric cali- brations of short-wavelength vacuum

ultraviolet radiation, which are essential

for space-based astronomy.

Using the Space Telescope

Two NIST scientists at the Joint Institute

for Laboratory Astrophysics (JILA) have

obtained observing time on the Hubble

Space Telescope. Jeffrey Linsky, an

astronomer and co-investigator on the

Goddard high-resolution spectrograph in- strument, will make high-precision measurements of the deuterium-to-hydrogen

ratio for interstellar gas, an important test

of some models of the origin of the uni- verse. He will also study six stars of very

low mass to learn whether they have atmospheres that resemble the Sun's

such stars are too faint to observe from

Earth and can be studied only from

space. David Hummer, an astrophysicist,

will work with colleagues at JILA and the

University of Munich to measure the

ultraviolet spectrum of hot stars in the

Magellanic Clouds, the galaxies nearest

to our own. With these data they will be

able to study the origin and evolution of

these stars which, unlike stars in our own

galaxy, appear to contain a much lower

abundance of elements heavier than hydrogen. JILA is a joint operation of NIST

and the University of Colorado and is lo- cated on the university's campus in Boulder, Colo.

NIST, 3IVI Sign Optical Fiber

Sensor Research Agreement

NIST and the 3M Company have begun

a cooperative program to develop components for optical fiber current sensors. These electric current sensors have

potential applications in the electric

power industry, electromagnetic pulse

and interference testing, and general

electronic instrumentation. Having no

electrical parts, fiber current sensors are

especially attractive in applications

where current must be measured at high

voltage or in the presence of electromagnetic interference. NIST has developed

certain technologies in this field, including methods for improving the properties

of fiber coils for sensing. A guest scientist from the 3M Fiber Optics Laboratory

in St. Paul, Minn., will spend a year working with researchers at the NIST Boulder

laboratories. NIST will share its knowledge with 3M, and the visiting 3M scientist will participate in further developmental work in fabrication, packaging, and

characterization of the coils.

Narrowest Spectral Line Produced

NIST researchers have made the nar- rowest known observation of an optical

spectral line. To do it, they developed the

narrowest linewidth laser ever produced.

Their work represents a big step toward an optical frequency time standard that

would be 10,000 times more accurate

than the best current standard (based on a microwave-range frequency of the

cesium atom). For a variety of reasons, a

time standard in the optical frequency

range would be very useful, and the more narrow the observed line, the more

accurate the standard.

The NIST researchers isolated a

single, laser-cooled mercury ion in an

electromagnetic trap and probed it with

the newly designed laser with an effective linewidth of about 86 Hz at a

wavelength of 563 nanometers. The

frequency observation was more than

10 times narrower than any previous

such attempt. A time standard based on

such a system could be accurate to a

part in 10^^, compared with the current standard, which is accurate to a part in

10^"^. For a copy of paper no. 13-90

describing this work, contact Jo Emery,

Div. 104, NIST, Boulder, CO 80303,

303/497-3237.

Ten Agencies Using NIST,

Treasury System for EFT

A system designed by NIST and the Department of the Treasury now is being

used for electronic funds transfers (EFT)

by 10 federal agencies. The system al- lows federal agencies to request electronically disbursement of funds from the

Treasury and allows the Treasury to

safely and quickly make the payments

requested by the agencies. Previously,

2
requests were mailed from the agencies

to Treasury financial centers. Over the

past several years, NIST researchers

have been working with the Treasury to help protect electronic funds transfers.

They have developed test methods to validate that devices used to authenticate financial messages correctly implement federal and industry standards.

They also developed a test to validate

systems that distribute the keys needed

to scramble or unscramble the electronic

messages. Over the next 2 years, 300

government sites are expected to implement the new disbursement system.

Upgraded Program Aids Police

Veliicle Selection

Police fleet managers seeking economy

and appropriate features can use the

latest version of AutoBid, a computer soft- ware program that grades potential fleet

acquisitions on a variety of performance

parameters. The program incorporates

test scores published annually by the

Michigan State Police Department on the

dynamics, acceleration, speed, braking,

ergonomics, and fuel economy of vehicles. It helps users combine these scores with bid prices to determine the

lowest cost for needed performance.

Developed at NIST, AutoBid (Version

2.0) is the first major upgrade to the original NIST-created AutoBid program now

used in over 450 police departments.

The upgrade has new features such as

bar-graph displays, printed vehicle score data sheets, vehicle hardware comparisons, and access to data from several vehicle model years. AutoBid runs on most

personal computers and can be used

directly from a floppy drive or may be installed on a hard drive. Free copies of

AutoBid are available to interested police

departments from the Law Enforcement

Standards Laboratory, B1 16 Polymer

BIdg., NIST, Gaithersburg, MD 20899,

301/975-2757. Supplies are limited. AutoBid was developed for the National Institute of Justice as part of its Technology

Assessment Program.

NIST Seeks Halon Replacements

NiST researchers are working with the

U.S. Air Force as part of an 1

1 -year program to find replacements for fire suppressants known as halons. Halons are used widely as fire extinguishers be- cause they are safe, effective, and gentle

to expensive and sensitive facilities such

as computers and aircraft. However,

these chemicals, along with chlorofluorocarbons, have been identified as

contributing to the depletion of strato- spheric ozone. Under an international

agreement, their manufacture will be curtailed and possibly eliminated before the

end of the century.

NIST scientists will develop a set of

procedures to screen likely replacement

candidates for a wide variety of properties, such as fire suppression efficiency, ozone depletion and greenhouse warming potential, metals corrosion, stability,

and toxicity. They will identify an initial

set of about 100 compounds to assess and create a database to organize past

and future information about replacement

candidates.

Materials Designed To Help

Monitor Water Pollution

Environmental agencies, as well as

others studying pollution in the nation's

waterways, need materials containing an

accurate composition of various compounds as a check to verify the reliability

of laboratory instruments and methods.

Now NIST has developed a bottled

Standard Reference Material (SRM) for

this purpose. It contains marine sediment

with a wide range of pollutant compounds of interest to environmental scientists. The sediment material, which has

certified values for 1 1 polycyclic aro- matic hydrocarbons (PAH's), was collected from the Chesapeake Bay area

near Baltimore harbor. The material also

contains noncertified values for other

PAH's, polychlorinated biphenyls, and

chlorinated pesticides. It is available

for $241 from the Office of Standard

Reference Materials, Rm. 204, Building

202, NIST, Gaithersburg, MD 20899,

301/975-6776.

New Method To Detect Aluminum

in Blood Substitute

Patients needing emergency blood trans- fusions can be given infusions of albumin

as an initial replacement for blood loss. This practice eliminates the need for blood typing and can reduce the possibility of disease transfer. However, recent

studies have uncovered a problem with

albumin that could prompt other adverse

health effects: trace levels of aluminum.

In the past, aluminum was difficult to measure at these low concentrations. But

now, at the request of the Food and Drug

Administration (FDA), NIST researchers

have developed effective methods for measuring aluminum in albumin that combine several chemical analysis techniques. Laboratories in pharmaceutical

companies and hospitals can adopt

these methods to screen albumin products before they are marketed or used.

3
NIST also has measured aluminum levels

in a number of albumin samples the FDA

and manufacturers will use to ensure measurement reliability.

Concealed Ceilings and Fire

Are a Deadly Mix

A fire in a concealed ceiling space containing combustible materials can produce up to 50 times more carbon monoxide than a fire in an open area, posing a hazard even to those remote from the

fire, reports NIST. NIST experts advise

that where it is impractical to remove

combustible materials from these

spaces, containment, fire stopping, and

automatic suppression techniques need

to be considered. NIST made these rec- ommendations after investigating a fire which killed 16 people in the John Sevier

Retirement Center in Johnson City,

Tenn., last December. Although the fire was confined mainly to the first floor,

most of the deaths were on the upper

floors of the 11 -story building. Tennessee

state investigators reported that either a

love seat or chair was the first major item

to ignite. NIST researchers believe that

wood-fiber tiles hidden by a suspended

ceiling ignited within minutes and the fire spread rapidly, producing large amounts

of carbon monoxide-laden smoke.

PC Database Available

for Biochemists

A new computerized database for biochemists in industrial laboratories and

universities worldwide brings together for the first time all of the published information on the successful crystallization of

proteins and nucleic acids. An important

research tool for the design of new drugs

and chemical processes, the database is designed for personal computers. It contains crystal data and the crystallization

conditions for more than 1 ,000 crystal

forms of over 600 biological macromolecules. For each crystal entry there is a complete description of crystallization

conditions and related crystallographic

data. Also provided are evaluated critical data on the physical characteristics of

known crystals, including unit cell parameters, space group, crystal density,

and diffraction limit. NIST/CARB Biological Macromolecule Crystallization Database, Standard Reference Database 21,

is available for $300 from the Standard

Reference Data Program, A323 Physics

BIdg., NIST, Gaithersburg, MD 20899,

301/975-2208.

Electric-Field Meter Developed

NIST researchers have developed a new

isotropic, photonic electric-field meter

capable of measuring continuous-wave

electric fields from 10 to 15,000 volts-permeter over a frequency range of 10 kHz

to beyond 1 GHz. For pulsed fields, the

minimum detectable field is 1,000 volts- per-meter. The probe uses electro-optic

modulators and optical fiber leads to cause minimum perturbation of the fields

being measured and to ensure immunity

of the probe to electromagnetic interfer- ence. The probe's large bandwidth and

its unusual ability to measure both amplitude and phase are its salient characteristics. Potential applications include

electromagnetic pulse measurement, the

precise measurement of any pulsed field

of suitable intensity, and the measure- ment of fields with multiple frequency

components. For a copy of paper no. 63-69, which describes the probe, contact Jo Emery, Div. 104, NIST, Boulder,

CO 80303, 303/497-3237.

Quantum Zeno Effect Clearly

Demonstrated

Quantum mechanics, the theory and

study of matter and its interactions at the

atomic level, predicts that the very act of

observing a phenomenon influences the

behavior of that phenomenon. NIST re- searchers have confirmed one aspect of

this theory—that measurements of the

state of a system can prevent that system from changing its state. The more

frequent the measurements, the stronger

the effect, they found, confirming predictions by University of Texas theorists

that a continuously observed quantum

system can never change its state. This

is known as the quantum Zeno effect

after the paradox conceived by the ancient Greek philosopher, Zeno. One

consequence of the Zeno effect, which

has yet to be observed, is that a continuously observed unstable system, such

as a radioactive nucleus, will never decay.

The NIST experiments involved observations of a few thousand beryllium ions

contained in an electromagnetic trap. A

radiofrequency field was applied with the

proper frequency and strength to drive

the ions from one quantum state to a sec- ond one. These transitions were strongly

inhibited by observations made every

4 milliseconds; when the time between

observations was increased to 256 milli- seconds, the transitions occurred

readily. A paper describing the findings

is available from Jo Emery, Div. 104,

NIST, Boulder, CO 80303, 303/497-3237.

Ask for paper no. 14-90.

4
Lyons New Head

ofNIST

n February 8, the U.S. Senate confirmed the appointment of

John W. Lyons, a chemist and senior manager at the National

Institute of Standards and Technology, to head the 89-year-old

research agency. Lyons became the ninth director of NIST,

succeeding Ernest Ambler who retired in March 1989. Educated at Harvard and Washington University, Lyons is one of the world's

leading autliorities in fire and fire

chemistry. After working for 18

years in research and development for the Monsanto Company,

he came to the then-National

Bureau of Standards in 1974 to

create the agency's Center for

Fire Research, now internationally

recognized for its work in the computer modeling of fires. Beginning in 1977, he organized and then managed the NIST

National Engineering Laboratory,

the largest research unit in the

agency.

The author of three books and

numerous technical papers,

Lyons is a fellow of the American

Association for the Advancement

of Science and the Washington

Academy of Science. He serves on the Advisory Committee for Engineering; National Science Foundation; and the Board of Visitors,

College of Engineering, University

of Maryland. He served as a member of the Board of Directors,

National Fire Protection Association (1978-84) and ASTM

My top priorities

are: to provide more

services to

industry . . . to provide

teciinical support to

tiealtli and safety

services . . . and to

contribute to progress

in scientific and

engineering

researcii. . . .

(1985-86). Lyons is a member of

the American Chemical Society

and Sigma Xi.

His professional honors include election to the National

Academy of Engineering (1985),

the Presidential Rank Award of

Distinguished Executive (1981),

the Department of Commerce

Gold Medal (1977), and the Presidential Management Improvement Award (1977). He received

the 1986 Edward Uhler Condon

Award for his book. Fire.

Lyons' view of NIST's future as well as its role to help industry

is expressed in the following

questions and answers, which were taken from the confirmation

proceedings conducted by the

Senate Committee on Commerce,

Science and Transportation.

Question: What do you see

as NIST's most important activities and responsibilities in the

1990's? What are your highest

priorities?

Lyons: NIST should continue

its strong research program in measurement technology necessary to support quality assurance programs in industry, but should

increase its emphasis on

"generic" research in newly

emerging technologies. I firmly

believe that a strong developing

relationship between this federal

laboratory and U.S. industry will be all important if we as a nation

are to meet the competitive challenges of the 1990's.

My top priorities are:

to provide more services to

U.S. industry to help improve

5
John W. Lyons, NIST Director

quality, cost, and speed of

market response by focusing on

additional tectnnical support services and looking at different ways

to develop generic aspects of

new technologies;

to provide technical support to a number of efforts in health and

safety services where we have

special capabilities; and

to contribute to progress in

scientific and engineering re- search through both our research

and our supporting services to

the research community.

Question: How do the re- search and technical services

provided by NIST contribute to

U.S. industrial performance and

productivity?

Lyons: The Institute's technical services improve manufacturing practices in a number of

important ways, leading to better

quality and lower costs. Some

examples are:

Better process design. Design

is improved by application of our

reference data on materials and

process fluids. The data enable

the design of more cost-effective

unit processes both by improving

unit efficiency and by eliminating the need for overdesign to overcome the lack of accurate

knowledge.

Improved process control systems. We provide new sensors and sensing techniques, architectures for control systems, and

models and protocols for communications within automated

control systems.

Integrated process automation. We are assisting industry

with integration of automated machines into full systems. Our Automated Manufacturing Research

Facility serves as the public

testbed for new concepts in quality assurance in the automated

factory of tomorrow, new control

hierarchies, new interfaces, new

modular structuring of the auto- mated factory, and new devices

and techniques necessary to enable the integration.

The Institute's technical services speed the movement of discoveries to the marketplace by:

helping industry to characterize new products, for example,

by determining structure of new

molecules; supplying phase diagrams of new compositions, such

as the high-temperature superconductors; and providing new

ways to measure technical

aspects of a new product, such

as microdomains of magnetic

materials.

developing ways to measure

the performance characteristics

of new product families in their in- tended uses. Examples are electrical characteristics of integrated

circuits, patterns and gains for antennas, toughness of advanced ceramics, and the like. developing the needed tests and helping secure consensus on them for establishing fair and

equitable buying and selling of

new products in the marketplace.

We have developed over two

dozen procedures for specifying

optical fibers alone.

Question: What steps can and should NIST take to help U.S. companies improve the quality of

their manufacturing and the

speed with which they turn new

ideas into successful commercial

products?

Lyons: While many U.S. industrial firms are having trouble

competing in the global marketplace, the United States is still extraordinarily creative and continues to build a large fraction of

the first prototypes of new products. Where we are falling down

6
is in using our science and technology in going to market. NIST, as well as other federal technical

agencies, can do something

about these problems.

In general, Institute researchers work on products and proc- ess problems at the generic or precompetitive level where infor- mation is shared within the technical community. The Institute stays

away from proprietary areas be- cause we believe that they are

the private sector's responsibility.

We do try to provide supporting technical services that will help industry develop products

and processes, and some of

these services are useful to industry at all stages of commercial

development. For example, in the area of high-temperature superconductors, NIST researchers are

studying how to make thin films

useful in electronic devices.

Someday this will be a proprietary

matter, but right now we are in

the generic and precompetitive

stages and the community is sharing new knowledge widely.

In another case, improved

process control is needed by the

chemical processing industry.

The processes in general are proprietary, and information is very

closely guarded. The Institute works on the properties of proc- ess fluids, such as steam, and on

improved sensors for measuring

components of the process

stream for more efficient control.

The better the data, the more effective the process design, and

the more efficient the process performance. Closer control in general means higher quality,

fewer rejects, and lower costs.

The Institute's work in auto- mated factory control through

applications of microprocessors

computer-integrated manufacturing—has clearly shown substantial impacts on quality, cost, and

speed. The computer can map

errors in machines and automatically correct for them so no rejects are produced. We believe

that measurements for quality as- surance should be made on the

process (machines), not on the

products.

. . . the Institute

should build on its

strengths and continue

to develop the supporting technical services

it has traditionally

provided to industry.

Keeping the variability of the

machines under continuous control will guarantee quality products. This means quality measures are built into process

sensing and control and will no

longer be separate from the production line. A corollary is that

computerized design followed by

automatic programming of the

computer-controlled machines on

the factory floor for the first time

permits industry to make design

changes in products almost on

the fly and to make lot sizes as

small as one, economically. We

are stressing these types of

programs in our planning. The results should be improved productivity and competitiveness for U.S.

industry.

Question: What specifically

do you believe NIST should do in

the 1990's to help provide the

tools that American industry

needs (a) to spread the commercialization and reliable, costeffective production of new

emerging technologies, such as

high-temperature superconductors and high-resolution displays;

(b) to improve manufacturing

quality; and (c) to make steady in- cremental improvements in both

products and production

processes?

Lyons: I believe the Institute can continue to be helpful as industry strives to improve its competitiveness. First, I believe the

Institute should build on its

strengths and continue to develop the supporting technical

services it has traditionally provided to industry. These services—measurement techniques,

data, reference materials, calibration services, protocols for soft- ware interfaces, formats for data,

and proposed standards and

codes—are essential to the

functioning of industry and must

be maintained. The demand for such services is increasing every

year as the business world becomes more technically complex.

So a top priority will be to continue to strengthen these areas.

For the past decade and

more, we have been tying our new programs to new, advanced

technologies in the belief that

these technologies offer tre- mendous market potential in the

7
future. Thus we have channeled

much of our efforts into such

areas as biotechnology and bioprocessing, semiconductors and

superconductors, optical communications, advanced materials,

automated manufacturing, computer networking, and computer

security. We shall continue to concentrate on these new

technologies.

We have shifted emphasis

somewhat in our work from a

focus on the properties and behavior of products to the manufacturing processes needed to make

products. Thus, in our materials

programs, we are working on how to process rapidly solidified

powders into shapes as opposed

simply to characterizing the

powders, and how to process

composites and advanced ceramics rather than just publishing

data on these new materials.

Our factory automation program is entirely directed to processing. And our work on bioprocess engineering is aimed at

the design problems in scaling

up, from the laboratory to the

factory, processes to make biochemicals such as new genetically engineered drugs. We shall continue to emphasize processing, particularly on those aspects

that are generic to families of

products, and we shall stay out of

specific and proprietary areas. These services are all aimed

at improving the cost and quality

of U.S. products. In addition,

some of our services are aimed at speeding industry's response to

market changes by enabling

concurrent or parallel actions in engineering and production,

thereby shortening turnaround

times. Often speed in responding

to market demand is as important as price.

In addition to supplying technical services from our laboratory

work, we also operate the new external programs assigned to us in

the Technology Competitiveness

Act of 1988, particularly the regional Manufacturing Technology

Centers, set up to transfer manufacturing technology to small and

medium-sized businesses, and

the Advanced Technology Pro- gram, designed to assist U.S.

business in carrying out research

and development on precompetitive, generic technologies with

wide commercial potential.

And we shall continue to operate the Malcolm Baldrige

National Quality Award. The quality award program, which is funded by the private sector but

managed by the Institute, is having a major impact on industry

by increasing the motivation to

look closely at quality programs

and to learn how to do it better. Question: What tools does

NIST use to transfer its technology to industry?

Lyons: The Institute has

worked with industry for almost

90 years. We use a variety of

mechanisms to promote these

interactions.

The cooperative research and

development agreement is one. We have entered into about 70 of

these since 1986; about 50 are in

effect now. We have many other

contractual arrangements covering collaborations. For example,

we have about 200 industrial re- search associates at work at the

Institute under agreements

tailored for this purpose. We have

hundreds of other guest workers

and visiting academicians. We

find all of these arrangements

effective. In fact, we are very flexible in the way in which we deal

with industrial collaborators.

An important point is that the

Institute, unlike most other federal

laboratories, is chartered to work

with industry. It is our job to build

partnerships to define projects

jointly and to hand off the findings

to the industrial clientele. We

have assembled a number of

small consortia of industrial firms as sponsors of specific Institute

laboratory projects. Each participant puts in a few tens of thousands of dollars and gets back

the results of an effort manyfold

larger. This approach builds in both participation in project definition and transfer of the findings.

I believe we shall see in the

years ahead many more joint en- deavors between the Institute and

industry in which staff and re- sources from both sectors are

joined in research projects

some at the Institute, some elsewhere. I think we should do

more—and we will.

8
President Seeks

Boost for NIST in '91

he Administration's FY 1991 budget request includes

$198,408,000 for the National Institute of Standards and Technology, representing a $36.5 million increase over the current

>te NIST appropriation and would be the largest single increase

since the agency's inception. "This budget reflects the growing

awareness of the vital role played by NIST in supporting our nation's

industries and commerce," ac- cording to NIST Deputy Director

Raymond Kammer. "In recent

years, issues of quality and competitiveness have been established as major concerns for the

United states, but they have been

important to this laboratory since

1901.

"These requested increases

also are long overdue. Over the

past 15 years, U.S. industry has

increased its funding of research

and development by about 82

percent, and the government's

R&D funding has increased by

about 57 percent. During that

same period, our appropriated

funding has stayed essentially

flat; we are still operating on a budget from 1975," said Kammer.

Often cited as the only federal

laboratory with the primary mission of aiding U.S. industry, NIST

develops measurement and quality control standards and technology across a broad spectrum

of scientific and industrial fields. The agency was established in

1901 as the National Bureau of

standards and rechartered in 1988 as the National Institute of

Standards and Technology.

The major NIST programs that

would be affected by the pro- posed 1991 budget address four

broad areas of technology: proc- ess and quality control through

chemical measurements, information technologies, electronic technology, and intelligent machines

and processes. Specific areas

include:

Chemical measurements and

standards, which would be in- creased by $4.33 million to develop improved measurement

technology for chemical analysis.

An estimated 250 million analytical chemical measurements are made daily in the United States

for industrial processes or health

and safety at an annual cost of

$50 billion.

Bioprocess engineering, which

would be increased by $2.3 million to develop the engineering

data and procedures necessary

to scale laboratory developments

in biotechnology up to commercially viable manufacturing

processes. The United States

leads the world in biotechnology

research but lags seriously behind Japan and Western Europe

in moving this technology into the

marketplace.

Lightwave measurement

technology, which would be in- creased by $5.5 million to support accelerated development of

the data and standardized measurement methods needed by the

rapidly growing optical fiber and

optoelectronics industries.

Integrated Services Digital

Network (ISDN), which would be

increased by $1 million for work

on this new generation of information technology that combines

voice, video, and data in a single

communications technology.

NIST is leading an industry-wide

effort to coordinate the development of needed standards for commercial products.

9
Computer security, which would

be increased by $2.5 million to support research, standards

development, and technical

assistance programs for costeffective protection of computer

systems and the information they

hold. Under the Computer

Security Act of 1987, NIST is responsible for developing

standards and guidelines for nondefense computer security

throughout the federal

government.

Advanced semiconductors,

which would be increased by

$3.9 million to develop badly

needed measurement support for

the semiconductor industry. The

next generation of integrated circuits will incorporate features with

dimensions less than a micrometer, and measurements for many

aspects of the new processes

cannot now be made at the required accuracy. In the case of

x-ray lithography, entirely new

measurement techniques are needed.

High-temperature superconductors, which would be increased

by $1 .9 million to expand NIST

measurement support needed by

U.S. industry to develop the commercial products using the new

superconductors. With years of

experience in both superconductivity and ceramics research and

an unmatched combination of research facilities, NIST is in an

excellent position to aid industry

in this intensely competitive field.

Atomic-scale electronics, which

would be increased by $1 million

for basic research on the fundamental physical limits on the size

of integrated circuits. The re- search will involve measurement

technology at the quantum limits

of precision to support future

generations of microelectronic devices based on the manipulation

of individual atoms.

Intelligent processing of

.materials, which would be in- creased by $1.25 million to ex- pand collaborative work with U.S.

industry to develop in-process

sensors, process models, and

principles of intelligent control

needed for the efficient production of high-quality materials.

Sntelligent machines, which

would be increased by

$5 million to expand collaborative

research with industry on sensor

technology, product representation technology, and advanced control technologies for

manufacturing.

High-performance composites,

which would be increased by

$1 million to expand the NIST pro- gram in data and measurement

technology for composites, an important area of worldwide competition which is hampered currently by the lack of adequate

materials performance data and

process controls.

The proposed NIST budget

also includes two major items for

the laboratory's facilities:

Scientific computing upgrade, an increase of $3,122 million to upgrade and enhance computing

resources at NIST.

Retrofit of NIST facilities, $1 million to begin work on overhauling

and retrofitting the NIST laboratories in Gaithersburg, Md. (25

years old) and Boulder, Colo.

(35 years old).

The 1991 budget continues

funding for two technology transfer programs. The $10 million

Advanced Technology Program

will provide grants to industryled consortia to support research

in generic, precompetitive technologies. The Regional Manufacturing Technology Centers

program, which provides matching grants to universities and

nonprofit organizations, would

receive $5 million for use in

establishing centers for the transfer of new and innovative manufacturing technology to small and

medium-sized businesses.

The termination of several

smaller NIST programs ear- marked in the FY 1990 appropriations bill will result in savings of

$2 million. These programs in- clude the Boehlert-Rockefeller

Technology Extension Program

($1 .3 million), fire research on

ignition of upholstery ($250,000), a study of alternate refrigerants

($250,000), and the evaluation of

non-energy-related inventions

($150,000).

by Michael Baum

NIST Public Affairs Specialist

10
Looking for

'Good' Vibrations

NIST researchers explore fast chemical reactions

lot can happen in a few trillionths of a second. Billions of gasoline molecules can tear apart in an explosion that runs a car,

or countless trinitrotoluene (TNT) nnolecules can almost simultaneously blast apart to open a mine. Scientists can now seize

a trillionth of a second. Fast-pulsed lasers help them capture a

chemical reaction that zips by within that fleeting moment. NIST scientists

John Stephenson, Michael

Casassa, and Edwin Heilweil use

laser pulses to create play-byplay recaps of virtually instantaneous chemical reactions. Their

techniques reveal a new depth of

detail for the kinds of combustion

reactions that thrust rocl<ets through space and the biological

reactions that express the infor- mation encoded in genes.

The researchers bombard a

reacting sample with laser

pulses, controlling when each

pulse hits the sample within onetrillionth of a second. Each pulse

gives a profile of each of the

chemical players at that instant.

In addition to these quick

"probing" pulses, the researchers

strike their samples with larger

"pumping" bursts that add

energy to the sample molecules.

This energy excites vibrations in bonds holding the molecules together. Like connecting springs,

bonds normally bounce around a

little, but the laser pulses set them off at specific rates, or

frequencies, vibrating like fast- plucked violin strings. A molecule can only accept energy in

quantities that set off preferred

vibrations.

NIST scientists use laser

pulses to create

play-by-play

recaps of virtually

instantaneous

chemical reactions.

After adding energy with a pumping pulse, the researchers

follow up with smaller probing

pulses to disclose the identity of

the molecules present and how

much energy these carry in their

vibrating bonds.

How does the probing pulse

create a picture of the molecules

present and their energy? The

researchers send in probing

pulses containing different light

frequencies—which correspond

to different colors—and measure

those the sample absorbs. They

combine the results from each

frequency to create a profile of

absorbed frequencies called an

absorption spectrum. Scientists use such a spectrum like a fingerprint to identify atoms and

molecules and see how much

energy they carry.

At one time, scientists thought

they could control chemical reactions by shining laser light with

just the right frequencies to vibrate a particular chemical bond.

That vibration would break the

bond the way a bridge can collapse if shaken at its natural

frequency. In general, however,

scientists have found it doesn't

work—exciting just the right vibration has no effect.

11
The reason it fails, explains

Casassa, is that energy in one bond flows out into other bonds

in the molecule. With their quick

laser pulses, the researchers add

energy to chemical bonds and

track how much it dissipates

each trillionth of a second.

In one of their experiments,

they followed the energy dissipation as well as the reaction rate

for a gas of hydrogen azide

(HN3), as it split into an N2 and an HN. Stephenson and his colleagues received funding from

the Air Force to study this reaction because it resembles the

combustion of rocket fuels. The

NIST researchers sent in pumping pulses that vibrated either the

bond that was to break or other

bonds in the molecule. Their result? Pumping different modes at comparable energy had no effect on the rate that bond broke.

Casassa explains that vibrating this bond should speed up its

rate of breakage, if it weren't for one problem—energy vibrating

that critical bond dispersed too

quickly. "The vibration spreads

out to other bonds before any

chemistry takes place," he says.

"Even if you carefully choose

which motion you excite, you find

the initial motion doesn't affect

the rate of reaction because the

vibrational energy sloshes back

and forth between different chemical bonds."

The researchers have found

exceptions. Another molecule

under study, the nitrogen monoxide dimer (ON-NO), breaks

apart faster if they vibrate certain

bonds. This molecule—two NO

molecules hooked together between the two N's—rapidly

breaks into separate NO fragments when sparked with a boost

of energy.

The researchers bombarded

the NO dimer gas with pumping

pulses of two frequencies, each

exciting a different vibration pattern that indirectly stresses the

breaking bond. One frequency

stretched the two N-0 bonds symmetrically, while the other vi- brated those bonds antisymmetrically—so one stretched as the

other compressed.

The researchers

add energy to

chemical bonds and

track how much

it dissipates each

trillionth of a second.

The researchers were surprised to see that when they excited the antisymmetric stretching

mode the molecule broke up 40

times faster than when they set

off the symmetric mode. The result was particularly unexpected

because the less energetic, lower

frequency sped the reaction

most. If the mode of vibration

didn't matter, the higher energy

laser pulse would speed up a reaction more—simply because it

delivered more energy to the

sample.

Why didn't the vibrations in

the NO dimer dissipate too fast

to change the reaction rate, as

happened with HN3? "The bond

holding the NO arms together is weaker than the HN3 bonds,"

explains Casassa. "The vibrations

don't couple as readily through

such a weak bond."

Heilweil and his colleagues

have found even more unfore- seen exceptions in reactions that

take place on surfaces. Surfaces

of metal or glass often act as catalysts, speeding or slowing many

industrial and biological reactions

including those that digest food

or clean up toxic exhaust gases

in a car's catalytic converter.

Scientists don't fully understand how surface catalysts work.

Heilweil first studied one of the

better-understood systems

small glass beads with attached

hydroxyl groups containing an oxygen (O) and a hydrogen (H).

He shined laser light at a solution

of these beads, exciting vibrations in bonds attaching the O's

to the H's. The result surprised

Heilweil. As in the HN3 system, he

expected to see the laser energy

flow from the excited bonds

within a few trillionths of a sec- ond. Instead, the energy stayed

isolated in this bond about 1,000

times longer.

If quick energy leakage prevented the possibility of lasercontrolled reactions in other systems, could scientists make it work on surfaces like the glass

beads, which isolate energy in

the chosen bonds much longer?

Heilweil isn't sure but agrees his

results provoke further study.

He next studied reactions on metal surfaces—the most

12
NIST researchers Edwin Heilweil (right) and IVIichael Casassa adjust the fast-pulsed laser used to study instantaneous

chemical reactions.

common sort of industrial surface

reactions. He first chose models

for surfaces containing just a few

rhodium metal atoms and adsorbed carbonyl molecules with one carbon and one oxygen

each. He discovered these systems acted much like the glass

bead one. The energy he put into

the carbon-oxygen bond lingered

longer than expected before leaking into the metal surface.

This experiment used only six

or fewer rhodium metal atoms. He

got a different result using particles with more than 1 ,000 metal

atoms. Then, energy fed directly

to the carbon-oxygen bond

flowed into the surface 20 times

faster. He explains that metals

act differently when isolated in pieces of just a few atoms than

they do in bulk. In the larger

sample, electrons flow through

the metal and carry the energy

away better than in the smaller

piece.

Heilweil plans to do similar

experiments on components of DNA, the molecule that holds the

genetic code. He will focus on the

actual coding elements, known

as bases. Normally linked in

pairs, the bonds connecting them

must break for the DNA to ex- press or reproduce its genetic

code. Watching how these

molecules react to lasers may

reveal how their reactions work.

Heilweil believes a closer look at

the physics of these reactions

could reveal unknown details of

these reactions that underlie all

life processes.

by Faye Flam

Washington, D.C.-area

science writer

13
Milestone: 500

Very Good Ideas

Anewtechnique for finding oil deposits that promises to be more

sensitive than conventional survey methods is the 500th invention to be recommended by the National Institute of Standards

and Technology to the Department of Energy (DOE) for

possible assistance in development and marketing. Through

the Energy-Related Inventions Program, conducted jointly by NIST and

DOE, individual inventors and

small businesses can receive

practical assistance in developing and commercializing new

energy-related technology. At no

cost to the individual or business,

NIST provides evaluations of

energy-related inventions and rec- ommends to DOE those it considers promising. In turn, DOE

can provide financial support or help in moving the technology

closer to the marketplace.

The 500th invention to receive

NIST's recommendation is the

idea of John F. Clauser of Livermore, Calif. Clauser, a research

physicist, has developed a more

accurate way to measure variations in gravity. This is one of the

techniques geophysicists use to

find rock formations that can trap

oil and gas. Hydrocarbon

deposits normally are found in

light, porous formations, such as sandstone or limestone, that have

a very different gravitational pull

than heavier, denser rocks.

Clauser's gravity sensor is based upon an interferometer

that uses two beams of atoms to

measure gravity variations over a

certain area. When the beams re- combine, an interference pattern

of light and dark regions is created. The gravitational pull produced by the surrounding rock

will deflect this pattern depending

At no cost to the

individual or business,

NIST provides evaluations of energy-related

inventions and recommends to DOE those it

considers promising.

upon the density of the rock. By

analyzing the deflections, geophysicists can infer information

concerning the underlying layers

of rock formations.

"We anticipate that this pro- posed instrument will be 10,000

times more accurate than gravity sensors currently on the market,"

says George P. Lewett, chief of

the NIST Office of Energy-Related

Inventions. "As a result, hydrocarbon deposits that previously went

undiscovered could be identified

and developed," he adds.

Of the 26,906 inventions submitted to NIST since the program

started in 1975, NIST has recom- mended 500 for DOE assistance.

For the past several years, some

100 ideas have been submitted

each month. Out of these, an average of 3 to 4 have been rec- ommended to DOE.

Another recently recom- mended invention is that of Vlad

Hruby. His idea will help reduce

the amount of particulates re- leased into the air by processing

plants such as coal-fired powergenerating boilers, trash burning

plants, and smelters. Hruby, president of J. Busek Co., Inc., a small

research and development company in Needham, Mass., uses

static electricity to form large agglomerates of dust particles that

are collected more easily than individual particles.

Hruby's invention should

make it economical to remove

14
much smaller particles than currently possible. According to

Lewett, if the system performs as

predicted, the invention could ad- vance air cleaning ability significantly beyond what can now be

achieved with current technology.

Many of the inventions going

through the program have been

introduced successfully into the

market. As of December 1988, a

survey of the recommended in- ventors showed that, at some

point, 88 had sold products

based on their inventions. An esti- mated 25 percent of the supported inventors achieve sales.

Cumulative sales among this group since the start of the program exceed $400 million.

For example, Schenectady,

N.Y., inventor Ronald Brandon designed a packing ring that re- duces wear and allows a tighter

seal during normal operation of

steam turbines that drive electrical generators in power plants.

Damaged packing rings can cause energy losses of 1 to 3

percent. In 1987, Brandon

entered into an exclusive worldwide licensing agreement with

Quabbin Industries for manufacturing and marketing the packing

rings. Recent figures show multimillion dollar sales.

Karakian Bedrosian's invention makes it possible to ship

fresher-tasting produce, such as

tomatoes, long distances without

refrigeration. Conventional shipping in refrigerated vehicles is

energy-intensive and can cause

deterioration in taste and nutrition. Bedrosian, of Alpine, N.J., uses controlled atmosphere packaging to keep oxygen at a minimum and water vapor and car- bon dioxide at desired levels. Marketed under the trade name

"TomAHtoes," 909,000 boxes were shipped in 1988, with $42.4

million in retail sales.

Cumulative sales among

this group since the

start of the program

exceed $400 million.

An invention that passes an

initial review undergoes a

rigorous evaluation by the NIST

staff in conjunction with a national

network of hundreds of expert

consultants from government, industry, and universities. Typically,

NIST evaluators obtain written

opinions from at least two consultants on each invention evaluated.

Three key questions must be

answered: Is the invention technically feasible? Will it have a significant impact on the energy situation? Does it have a reasonable

chance of becoming a commercial success?

If the answers to all three

questions are "yes," NIST for- wards it to DOE for financial support and/or other help in further

development and commercialization. The one-time DOE grants

typically have ranged between

$50,000 and $200,000, with an average of $72,000 per invention.

Inventions that are not recom- mended to DOE do get the benefit of a free evaluation by NIST. If an invention does not warrant

further review, the key reasons

are identified and reported to the

submitter of the evaluation request, who frequently continues

development and tries again. "We

are always willing to reconsider our position if the inventor or company can provide further details

or new information," says Lewett. The assistance the program

gives to individuals and small

businesses does not stop at evaluations and financial and commercialization assistance. For the

past 10 years, the program has

sponsored a series of National Innovation Workshops held nationwide. The 2-day workshops give

practical guidance and information to inventors and entre- preneurs through lectures and

panel discussions. Advice is given on turning ideas into inventions and getting help from both

public and private sources.

In addition, NIST is working

with individual states in their efforts to stimulate technological innovation and industrial development. In one pilot project, Small

Business Development Centers

(SBDC's) in 15 states are seeking

out small businesses with ideas

for energy-related products to submit to NIST for evaluation. If NIST finds the new technology

lacks the required energy-saving

potential but still has commercial

promise, it is referred back to the

originating SBDC with guidance

to the company and the SBDC on

further development.

For more information on these

programs, contact the Office of

Energy-Related Inventions, NIST,

A115 Building 411, Gaithersburg,

MD 20899,

by Jan Kosko

NIST Public Affairs Specialist

15
Measuring in the

Lilliputian Worid of

Semiconductors

Nobigger than a fingernail, no thicker than a snowflal<e, senniconductor chips bring to life all kinds of electronic wonders,

from connputers to television sets to automobile ignition

systems. These chips endow machines with the power to

calculate and to remember—enabling automatic teller

machines to compute your account balance, or the subway ticket reader

to judge whether you've paid

enough fare.

Picture the structure on one of

these chips as the streets of all

the cities in the United States

crowded onto a postage stannp.

Unlike the clogged traffic of the

cities, electric charges glide

along the chip's corridors in a

controlled flow that does the work

of the chip. The chip (also called an integrated circuit) will work

only if the manufacturers construct everything just right, like a

network of streets—each with just

the right width, containing just the

right composition of materials,

lined with just the right shapes

and sizes of buildings.

On this chip cityscape, the individual streets elude the human

eye, even with the aid of a conventional microscope. Manufacturers must grope through this invisible world, not knowing the

dimension or composition of the

circuit they produce. So many

things can go wrong that chipmakers sometimes must throw

away 95 percent of their finished

product.

The defective chips waste

chipmakers' time and money as

they roll on through the 100-step

production process. For manufacturers, the key to saving money is

to measure the critical properties

and dimensions of chips during

production, pulling bad ones out as soon as possible. The better

they measure, the greater the percentage of good chips. "Measurement provides the underpinning

for our ability to manufacture reliable, high-quality chips," says

NIST's Semiconductor Electronics

Division Chief Frank Oettinger.

Measurement figures so prominently in the chip industry that

companies spend about a quarter of their production costs on measurement.

NIST provides companies with

the methods to measure dimensions and properties of chips.

The diminishingly small dimensions on the chips challenge

Measurement figures

so prominently in

tlie chip industry

tliat companies spend

about a quarter

of tlieir

production costs

on measurement.

NIST scientists to develop new

ways to describe and measure

their intricate structure. "The

detail on chips today has become

so small that we are measuring

things today that were almost

unmeasurable just a few years

16
ago," says Robert Scace, Deputy

Director of NIST's Center for Electronics and Electrical Engineering.

The chip itself might fit onto

the little fingernail of the NIST

engineer trying to measure the

thicknesses, widths, compositions, or electrical properties of

the individual devices. The re- searcher might send in small messengers—electrons or light

waves—to obtain information on

the chip's dimensions.

Their quest for more accurate

measurement in increasingly

small dimensions often brings

NIST semiconductor researchers

into the realm of new technology.

Many of their measurement techniques help NIST and industry re- searchers understand and har- ness new developments, such as

chips made from compounds

other than silicon, for example, or ones that replace electric current

with light waves. NIST re- searchers sometimes mal<e experimental versions of such chips

and other times perform measure- ments on ones from outside

sources. When NIST researchers

develop a successful measure- ment technique, they often produce a certified "yardstick" called a Standard Reference Material

that companies can use to check

their own measurements. Companies need these Standard Refer- ence Materials to calibrate their

instruments so that a reading of a

millionth of a meter or a part per

billion concentration means the

same thing on one company's

instrument as on the next.

NIST devotes an entire division to semiconductor electronics. This division consists of four

closely related groups—materials, processes, devices, and in- tegrated circuit technology. NIST

researchers in other areas also

contribute their expertise to the

semiconductor arena. Through

collaborative research agreements, private companies donate

equipment, researchers, and

money to NIST's efforts. In addition, NIST works with SEMATECH,

a government-industry consortium set up to boost U.S. competitiveness through researching

chipmaking technology. NIST

also collaborates with the Semiconductor Research Corporation, an industry consortium set up to

fund research and to train future

employees of the U.S. electronics

industry.

The Stuff of Chips

Researchers in the NIST materials

technology group study the substances from which semiconductor chips are made. The materials of the chip, in the form of

transistors, do the actual work,

controlling the flow of electric current and using this current to re- member information and do

calculations.

To make paths of doped material into useful circuits, the chipmakers need to put just the right

amounts of impurities into just the

right patches. Therefore, they

need to be able to measure dopant concentrations and the

NIST researchers use this prober for deep-level transient spectroscopic

studies of defects in electronic thin films.

17
electrical properties of doped regions. Manufacturers must also

know about the accidental impurities and structural defects that

creep into the chip during production. "As integrated circuits become more sophisticated, they

require more and more exact impurity concentrations," says

group leader David Seller. "Just a

bit too much or too little and the

circuit won't work."

teriai's chemical composition and

crystal structure. One of NIST's instruments, an

ellipsometer, measures thin layers of semiconductor materials.

Numerous such layers stack up

on a chip, with structure carved

out through them.

The ellipsometer sends light

into a thin layer of material and

reads the reflected light to determine the material's index of refracAt the request of industry, electronics engineer Harry Schafft and his colleagues developed the

technical basis for three test methods for evaluating electromigration, a serious failure mechanism

in semiconductor integrated circuits.

Some materials researchers use tiny electrical probes to measure how easily electric current can flow through stretches of

the chip's circuitry. Other re- searchers shine light on silicon

samples and read the light scattered back off to see into the mation (how much it bends light waves passing through) as well as the thickness of a layer. "Both

these properties are fundamental

for determining quality," says

Seller. The ellipsometry team

has issued a set of Standard Ref- erence Materials, in this case samples having layers with welldefined thicknesses and indices

of refraction.

A Hundredth of the Width

of a Hair

In NIST's Precision Engineering

Division, researcher Robert

Larrabee pursues the width of the

streets, buildings, and bridges

criss-crossing the chip and connecting its parts. These structures can be smaller than a millionth of a meter wide or 100 times thinner

than a hair. Companies need to know

the width of these electrically

conducting lines to prevent the

lines from connecting in the

wrong places and allowing the

current to take a disastrous short

cut, or short circuit. But these

widths elude sight even with the

help of ordinary microscopes,

since the wavelength of light

exceeds their dimensions.

Larrabee shows how light reflected from a chip structure produces an erratic line with no

definite edge from which to begin

or end the width measurement.

While use of an electron microscope—one that substitutes electrons for light—solves some of

these problems, other problems

are introduced.

Even perfect magnification

would reveal boundaries that jut

in and out like jagged sea cliffs. "How can you measure the edge

when there is no definite edge?"

he asks. Larrabee explains that

he can more easily measure the

distance between the right edges

of two similar lines because he

18
can define the edge of one line and measure to the corresponding point on the other. But the

width of any one line depends on where he defines edges within

the jagged contours of the structure. "Maybe we ought to call our work edge determination instead

of width measurement," he adds.

Larrabee says most major

semiconductor companies have

asked him to deliver Standard

Reference Materials that determine widths as narrow as onetenth of a millionth of a meter with

greater than 1 percent accuracy.

"They are asking for a measure- ment accurate to within a few

atoms," says Larrabee. "Right

now, it's an impossible measurement." Though faced with such an insurmountable task today, he

envisions a way to tackle these

problems using better theoretical

prediction. A computer will act as

sleuth, taking in the available information and using scientific

theory to estimate the unknown

dimensions.

About a decade ago, NIST re- searchers achieved a major tri- umph over small dimensions

when they developed the first accurate measurements of the

widths of structures on a photomask—a tool for etching circuits on chips. The photomask works

like a stencil, allowing light

through certain spaces to help

etch a pattern in light-sensitive

chemicals. NIST, then NBS, sold

companies special photomasks

with slits of standard, premeasured widths, and many companies greatly improved the ac- curacy of their chip dimensions

as a result.

The Making of a Chip

Researchers in NIST's own Semiconductor Processing Research

Laboratory fabricate many of the

semiconductor structures and devices that other NIST groups use

to investigate, measure, and sell

to private companies as Standard

Reference Materials. In the processing laboratory, NIST re- searchers construct the intricate

circuitry on semiconducting chips

using the same principles that private companies use.

"As integrated circuits

become more

sopliisticated, tiiey

require more and more

exact impurity

concentrations.

Chipmaking can take more

than 100 steps. First, manufacturers must prepare a mirror-finish

disk, or "wafer" of crystalline sili- con a few inches across, which

will contain many copies of the

chip. On the wafer's surface, they

grow very thin layers of other materials. Then they etch the wafer

with the delicate pattern of circuitry. They carve out precisely

delineated spaces for dopants,

with a technique akin to photography called photolithography. To

do the photolithography, they

must deposit layers of lightsensitive chemicals. Then, the re- searchers shine a light on the

wafer through a photomask that

lets light through certain spaces

to impart the pattern. The unex- posed regions protect underlying

layers, while in the exposed regions, the chip manufacturers can etch away some of these layers. They can then deposit

patches of dopants to the etchedout spaces. Finally, the manufacturers divide the wafer into individual chips.

To grow very precisely controlled thin layers of semiconducting materials, researchers use

molecular beam epitaxy (MBE) to

build up a thin layer by shooting narrow beams of molecules,

slowly growing the layer over a semiconductor surface.

NIST researchers Joseph

Pellegrino and Wen Tseng say

they are now using MBE to grow

thin layers of the semiconducting

materials gallium arsenide (GaAs)

and aluminum gallium arsenide

(AIGaAs). These materials sometimes replace the more abundant

silicon for certain specialized

uses. Unlike silicon, these other

compounds can convert electrical signals to light and back to

electricity again. This conversion

ability may lead to optical computers and other fast-acting devices

that use swifter light waves to

transmit signals. By testing different GaAs and AIGaAs structures,

Pellegrino and Tseng strive to help find better techniques for

controlling the recipe for devices

prepared from these compounds.

Checking the Result

Inevitably, defects and manufacturing errors creep into semiconductor devices in the many-stage

chipmaking process. Semiconductor makers expect to produce

19
some fraction of chips that worl<

(the "yield") and to throw away

the rest, never l<nowing what went

wrong. NIST's integrated circuit technology group works to improve the yield by identifying the

roots of defects.

The group diagnoses chip

flaws using test structures—small

samples of integrated circuit components that sit off to the

side of the worl<ing parts. The

researchers check these sample

circuit elements and, with the

NIST electronics engineer David Berning developed an

instrument that nondestructively tests electronic switctiing

components found in control systems for applications

ranging from the main engines of the space shuttle to automobiles.

help of a computer, produce data

revealing which parts of the proc- ess have gone awry.

However, measuring test

structures can generate mountains of data, according to group

leader Loren Linholm. "The per- son on the assembly line doesn't

want ten zillion bits of data," he

says, "He wants to know what's

wrong." To condense the over- abundant data into a more usable

form, he and his colleagues,

Dheeraj Khera and Michael Cresswell, are collaborating with IBM

on a computer system that absorbs a pile of data, weighs probabilities, and estimates the most

likely causes of a processing

problem. Linholm's vision of this

"expert system" will digest stacks

of pages of numbers and produce plain English statements

like, "Your oxide layer is too thick"

or "Your light exposure was

uneven."

Improving the Finished

Devices

How do the chips work when they

are incorporated into devices?

How can the devices work better?

The device technology group fo- cuses on these questions. Some

of the researchers delve into the

inner workings of semiconductors

to create theories about the ways

electric charges propagate

through the devices. Others study

better ways for industry to "package" chips into saleable devices.

Still others work with "power" devices that regulate the electrical

power channeled into homes and

industries. Unlike computer

chips, power devices generally

carry large electric currents. Though power devices normally handle large currents and

voltages, too much electricity can

destroy them. A NIST device

team has devised a new way to

test the limits of power devices.

Normally, in such a test, the re- searcher sacrifices the device.

The NIST testing apparatus, however, warns of the first signs of

failure and then very quickly

shuts off the current before the

device fails and burns out.

Beating the Competition

All these NIST projects are

helping to bolster U.S. industry in

the face of formidable Japanese

and European competition. In

1980, Japan captured the U.S. lead in the integrated circuit busi- ness and now threatens to take over more of the market. According to Scace, the Japanese have

broken ahead by constantly striving to improve their production

and by risking short-term losses

to achieve future advances.

NIST's measurement techniques help U.S. companies fight

back by improving production

and cutting costs. In supporting

this work, NIST research has re- vealed some of the underlying

physics and chemistry of semiconductor chips. With a deeper

scientific understanding, manufacturers can get at the root of

problems and can engineer better integrated circuits. But as technology advances,

old measuring methods grow obsolete, says Scace. With new

technology come new measure- ment problems, which the semiconductor researchers agree

should keep them busy far into

the future. F.F.

20
Loma Prieta: A Primer

for Public Policy

nexpectedly severe damage to buildings in the San Francisco

Bay area during last October's Loma Prieta earthquake underscores the lesson that structures sited on deep soil deposits

need to be assessed to determine their earthquake safety, according to a study by the National Institute of Standards and

Technology. "Lifelines," such as bridges, highways, and water and gas

pipelines, also are vulnerable to earthquakes and should be

assessed as well, according to the NIST report.

The earthquake provided significant lessons for public policies

and construction practices in the

United States, said NIST. "While it was the largest earthquake to

strike northern California since

the great San Francisco earthquake of 1906, earthquakes of

similar or larger magnitude are expected to affect 46 of the 50

states, Puerto Rico, and the Virgin

Islands," the report noted.

NIST conducted the investigation at the request of Congress,

bringing together a team of civil,

fire safety, geotechnical, and

structural engineers from various

federal agencies representing the

Interagency Committee on

Seismic Safety in Construction.

Many of the findings reflect lessons already learned from previous quakes and research, said

Richard Wright, director of the

NIST Center for Building Technology, but they are important be- cause in many earthquakethese damages

occurred to structures

located on deep

unstable soil

deposits.

susceptible parts of the country

structures are not designed and

constructed in accord with modern seismic safety practices.

Not surprisingly, NIST found

that older wood-framed dwellings

and unreinforced masonry buildings which had not been

strengthened sustained substantial damage. In addition, notes

the NIST report, "... many modern buildings also have these

vulnerabilities in seismically hazardous areas of the United States

which have not yet, or only recently have, adopted and enforced seismic design and construction provisions in their

building codes." Most structures designed in accordance with

modern codes and standards

performed well without serious

structural damage, said NIST.

Somewhat unexpected, however, was that many structures in

the Bay area of San Francisco, 60

to 70 miles away from the earthquake's epicenter, suffered severe damage, included were some buildings constructed using

modern seismic safety practices.

"At such distances, for this size

earthquake, current seismic design and construction practices were expected to be capable of

preventing structural damages,"

said the NIST report.

To a large extent, these damages occurred to structures lo- cated on deep unstable soil

deposits, noted the NIST researchers. Most buildings on

firmer ground sustained little or no damage.

During an earthquake, deep

soil deposits over bedrock amplify some frequencies of ground

motion causing the soil to act like

gelatin. Such sites are common in

other areas of the country that are

subject to earthquake hazards.

"We have seen this occurrence

21
before, most recently in the

Mexico City eartlnqual<e in 1985,"

said Wright, "but this amount of

damage at this distance from the

earthquai<e was not anticipated in

current seismic provisions for

buildings and lifelines." Another lesson reiearned is

the importance of lifelines to a community's safety and econ- omy. But, until recently, most

research on earthquake performance of structures and development of relevant design and construction practices concentrated on building construction. Im- proved design, assessment, and

retrofit practices are needed for

lifelines, said the NIST report.

The Loma Prieta earthquake

caused severe damage to the

area's highway network, most notably to Interstate 880 and the

San Francisco-Oakland Bay

Bridge, as well as to its water and

gas distribution systems. As with

damage to buildings, unstable

soil may have played a part in damage to lifelines, said NIST.

Like much of the U.S. highway

system, 1-880 was built in the

1950's and was not designed to withstand earthquake forces, said

NIST. While many questions re- main about precisely how 1-880

failed, NIST concluded that at

Unstable soil played a major role in the damage of buildings and "lifelines"—bridges, highways,

and water and gas pipelines—during the October 1989 Loma Prieta earthquake in the San

Francisco Bay area. These figures, from the NIST report, show the surface geology of the area (below) and the correlating damage (right).

• Contour of 60m (200 ft) depth of unconsolidated deposits i> ^ i Alluvium, 0-30m thick

] Shallow bedrock

22
least two different factors could

have contributed to its failure:

strong vibrations possibly

caused by amplified ground

motion and inadequate confining

steel in the support columns.

Also, NIST determined the structure was "nonredundant," meaning a failure of a single structural

component could have led to wider failure. Except for major or

partial collapses at three bridge

sites, including the collapse of a span of the San FranciscoOakland Bay bridge, most of the

1 ,500 bridges in the area sur- vived the earthquake with relatively minor damage. During the

past 15 years, most bridges

and viaducts had been

strengthened in the California

Department of Transportation

seismic retrofit program.

As part of the National Earthquake Hazards Reduction Pro- gram, established by Congress in 1977, NIST conducts research

and provides technical support to

the private sector and government agencies that are working to improve the performance of buildings and other structures subjected to earthquakes. Since

1971, NIST has participated in

nine earthquake investigations, including those in Mexico City in 1985 and in Armenia in 1988.

A copy of the NIST report.

Performance of Structures

During ttie Loma Prieta Earthquake of October 17, 1989

(NIST Special Publication 778),

may be purchased from the

National Technical Information

Service, Springfield, VA 22161 for $31 .00 (order by PB #90-184599)

or from the Superintendent of

Documents, U.S. Government

Printing Office, Washington, DC

20402 for $1 1 .00 (order by stock

no. 003-003-02988-2 ). U.K.

Golden Gats'

8rid$e

Outer limit of bay mud deposits

Contour of 60m (200 ft) depth of unconsolidated deposits

Area of damage concentration

® Major damage to highway structures O Minor damage to highway structures A Major damage to buildings

A Minor damage to buildings

23
More Than Just for

Safety's Sake

Ithough safety is a motivating factor beliinci much of the building and fire research at the National Institute of Standards and

Technology, it is not the only one. The other driving force is

economics—both in helping industry to save dollars and to

remain competitive in an ever-growing world market. The U.S.

construction industry is losing ground to foreign competitors in both the

international and domestic

markets. According to the Commerce Department's 1989 U.S.

Industrial Outlook, awards to U.S.

contractors in overseas markets

declined by 60 percent from 1982

to 1987. This year's edition of the

Outlook reports that foreignowned construction firms won

$12.7 billion in U.S. construction

contracts in 1988—up from $3.6

billion in 1982. Almost everyone

will agree that technical leadership is essential to the competitiveness of this country's construction industry.

NIST research, primarily in the

Centers for Building Technology

and Fire Research, is helping the

building industry in the United

states regain its technical leadership in construction and improve

its standing in the international

market. "It's our job to make sure

the building industry in this country is equipped with the technical tools and knowledge

needed not only to produce safer

structures but also to help improve the quality of construction

products and services, and, in

turn, economic competitiveness,"

says Samuel Kramer, acting head

of the NIST National Engineering

Laboratory.

Building Open Systems

A key element for economic

strength in the international building market is "open systems" for

construction products and services, says Richard N. Wright,

director of the NIST Center for

Building Technology. For instance, an open system permits an improved thermostat made by one firm to be used in an existing

temperature control system supplied by another vender.

As the building community

increasingly relies on computers, an open system allows computers from different manufacturers

to communicate. In this country,

it is common for a construction

team to be unique for each project. Each member of the team

may have a different system of

hardware and software, making it time-consuming and difficult, or even impossible, to exchange

information.

At NIST, research has fo- cused primarily on developing

standards to allow specific construction-related information to be

exchanged among different computers. Once completed, these

standards will help make it easier

to pass information among the

various members of a team. Both

time and money will be saved as team members can more quickly

come to decisions regarding their

particular construction project.

Better Building Blocks

In another area, NIST researchers

are developing new techniques

and tools to help improve the performance, strength, and durability

of building materials such as concrete. In the United States alone,

billions of dollars are invested annually in millions of tons of concrete used to construct buildings,

highways, dams, and bridges.

The longer these last, the more

the country gets for its investment. But many of these structures are deteriorating years

before they should, according to a National Research Council report. That drains dollars that

24
could be spent elsewhere in the

econonny.

The NIST researchers are

using connputer technology conn- bined with sophisticated techniques, such as electron microscopy and computer image

analysis, to learn more about the

behavior of concrete and the factors that control its strength and

durability. Armed with this knowledge, they are developing computer models that ultimately may

be used to predict the characteristics of concrete, such as

strength and durability.

Another tool being developed

at NIST uses an old technique in a new way to find flaws in concrete. Known as "impact-echo,"

the technique works on the same

principle as the sonar pings used

to locate and determine the depth

of a submarine. It can be used on

plain or reinforced concrete to determine where flaws are and to estimate their sizes. The research

will form the basis for a simple,

easy-to-use method for routine

evaluation of concrete, thereby in- creasing the safety of concrete

structures and decreasing the dollars spent on major repairs.

Building for Eartliqual<es

Strength of concrete is a major

consideration when building,

especially when designing structures to resist earthquakes. As

part of their work to improve the

performance of buildings and

other structures subjected to earthquakes, NIST researchers

subjected several full-scale concrete bridge columns to earthquake-like stresses. "These tests,

which are the first of their kind in

the United States, are giving us

knowledge about how very large

concrete structures perform

during earthquakes," says Wright.

Since the test setup at NIST is unique and would be costly for in- dustry to duplicate, a companion

series of tests on smaller versions

of the columns has been con- ducted to determine if research on small specimens can be extrapolated to the large sizes. In

addition, the researchers are developing computer models

which can be used to predict how

these structures will hold up

during an earthquake. This infor- mation will result in bridges that

not only are safer but also less

costly to build if it is determined

that current standards require

them to be overdesigned. The

National Science Foundation, Federal Highway Administration, and

the California Department of

Transportation helped fund this program. (See article on page 21.)

Tlie Race for CFC Substitutes

in another area, NIST is working

closely with U.S. industry to help

in the search for alternative

chlorofluorocarbons—better

known as CFC's—by developing

data on the properties of likely

candidates. "This information is

vitally needed by industry to help

As part of a collaborative research project at NIST, whicli is sponsored by the Electric Power Research Institute, mechanical engineer Mark Kedzierski studies the effects of new atmospherically

safe refrigerants and refrigerant mixtures on refrigeration systems.

25
Vytenis Babrauskas, head of the NISTfire toxicity measurement group, monitors a sample in the NIST cone

calorimeter, which is used to determine how furniture burns.

evaluate possible replacements,"

says Wright.

Damage to the Earth's ozone

layer by CFC's has industries

worldwide racing to develop commercially viable substitutes as

well as equipment that use them

effectively. In the United States

alone, more than $100 billion worth of products rely on CFC's,

including refrigerators and home

insulation.

The American Society of

Heating, Refrigerating and Air- Conditioning Engineers, the

Environmental Protection Agency,

the Department of Energy, and

the Air Conditioning and Refrigeration Institute are helping

to fund the NIST research. In addition, the Air Conditioning and Refrigeration institute is encouraging its 170 member companies to provide refrigerant data to NIST.

The long-standing refrigerant

research program at NIST also

has shown that the efficiency of

heat pumps and air conditioners can be increased markedly by

using a mix of refrigerants.

Other NIST research includes

studies on structural reliability,

which can reduce design and

construction costs, and on the interaction of lighting and heating,

ventilating, and air-conditioning

systems—research that could

result in millions of dollars being

saved on lighting and airconditioning costs. Also being

looked at are techniques to predict thermal performance, which can be used as the basis for com

mercial computer programs for

building design, and the service

lives of building materials. In add!

tion, NIST economists have devel

oped numerous methods to help

building owners and designers

make economically sound

26
decisions. TInese methods are now standard practices for the

industry.

Reducing Fire Losses

In an adjoining building, other

NIST researchers are worl<ing to provide the scientific and engineering knowledge needed to re- duce this country's fire losses

both hunnan and economic. "Compared to other countries, the

United States ranks number one

in a lot of different areas," says

Jack E. Snell, director of the NIST

Center for Fire Research, "but

when it comes to fire safety, we're near the bottom." Each year fires

in the United States result in over 6,000 deaths, over 28,000 injuries, and $7.1 billion in direct property losses; the total cost to the

nation is close to $40 billion. To help minimize these losses

and to help U.S. industry stay

competitive in the world market,

better tools are needed for predicting and controlling the risk of

fire. For example, the loss of

unique software, data, and equipment through fires could lead to economic disaster for U.S. hightechnology firms competing in world markets.

Computer Models

NIST, through its Center for Fire

Research, is a world leader in developing computer models to

simulate fires. These models give

engineers, architects, building

owners, and others the knowledge to improve fire safety at a reduced cost. The NIST models

make it possible to duplicate real

fires without having to burn a

room or building. Several models

are available and some can be

used on personal computers.

"These advances have launched a revolution in how fire is thought

about, planned for, and confronted," says Snell. One such model, known as HAZARD I, makes it possible to

predict—under a limited set of

scenarios—^the spread of smoke,

toxic gases, and heat from a

fire in a room to other parts of a building. Among other uses, HAZARD I enables product

manufacturers to examine fire scenarios that include their products. It also allows builders, architects, engineers, and fire investigators to assess fire behavior in

specific building types. The NIST

scientists and engineers use the

models, along with other techniques, to help analyze and reconstruct fires. Recent cases in- clude the Dupont Plaza Hotel in San Juan, a board and care resi- dence in Sharon, Pa., the First Interstate Bank building in Los Angeles, and a retirement center in Johnson City, Tenn.

IVIaterials Testing

Other tools are being developed

to help replace time-consuming

and expensive full-scale tests that

drive up the costs of the finished

products. Traditionally, manufacturers conduct full-scale burn

tests on a new piece of furniture

to determine its burning behavior.

As a more efficient and less

costly alternative, NIST is developing small-scale measuring

methods that provide even more

information than the full-scale ones and at a reduced cost. For

example, an instrument known as

the NIST cone calorimeter provides the data critical to predicting the fire hazard of a product

from a small sample of material.

The U.S.-based ASTM has

adopted a voluntary fire hazard

test method based on the instrument. It also is being considered as a standard test method by the

International Organization for

Standardization. Commercial

units now are sold by five manufacturers in the United States and

abroad, and a rapidly growing

number are in use worldwide.

Other research includes work

to develop better test methods for carpet flammability and drapery

material. In addition, basic re- search in areas such as soot for- mation and polymer flammability

will lead to safer materials. While

much of the work emphasizes

ways to prevent fires, research on

sprinklers and other extinguishment systems is finding better,

less expensive ways to put out

fires. In work for the U.S. Department of the Interior, the NIST re- searchers are finding that it is

possible to extinguish hazardous,

costly oil well blowout fires with

extraordinarily small amounts of

water properly applied.

"While NIST cannot singlehandedly put the U.S. building

industry back on top," says

Kramer, "our research, often in

collaboration with industry, does

contribute by improving not only

building safety, but also the

quality of products and services to make them more

competitive." J.K.

27
stress and Strain on

the Railroad Train

rlickety-clack, clickety-clack, clickety-clack. ... For some of

us, that hypnotic rhythm is a nostalgic reminder of train trips in

our youth; for others, it's still a significant part of daily life, commuting to and from work. But think about the source of that

pulsing cadence: the impact of steel wheels on steel rail joints,

135 times a mile, mile after mile, day after day.

That's a lot of impacts, and for every passenger car, there are

nearly 600 freight cars crisscrossing the continent. That makes

nearly 12 million clacking steel wheels clicking along 260,000

miles of track in the United

States. It all adds up to a lot of

stress on the wheels: stress from

loads being carried, stress from

impacts on rail joints, and stress from heat.

Despite the inroads made by

automobiles, trucks, and planes,

the railroads remain a major component of our national transportation system, hauling coal, grain,

machinery, and other goods

more than a third of the total

freight moved each year by all

carriers.

Most of us take the sound

and the soundness—of the

wheels for granted, but not the re- searchers at the National Institute

of standards and Technology.

NIST is working with the Federal Railroad Administration (FRA)

to develop more reliable and efficient ways to detect high stress

levels and cracks in railroad

wheels. A team of scientists and

engineers from the Materials Reliability Division at the NIST

Boulder, Colo., laboratories, is studying the use of sound waves

to determine the type and direction of stress, and the location

and size of cracks.

NIST is working

to develop more

reliable and efficient

ways to detect

high stress levels

and cracks in

railroad wheels.

Some cracks form in the sur- face of the treads of railroad

wheels. If the stress at a tread

crack grows too large, the tread can literally peel off. NIST is developing an instrument to detect and measure these cracks.

using an electromagnetic acoustic transducer, or EMAT.

Basically, an EMAT is a device that sends ultrasonic waves

into the wheel and then detects

them when they return. The EMAT

generates the waves electromagnetically, rather than mechanically, giving it an advantage over most other kinds of ultrasonic

transducers used to detect flaws:

It does not have to be in direct

contact with the material being

tested. The device also lends itself to situations where the material is rough or dirty.

One kind of EMAT is designed

to produce a wave that travels

along the surface of the tread,

making up to 14 trips around the

wheel. When the waves en- counter a crack or other flaw,

they are reflected back to the

EMAT. The time it takes for the

echo to return indicates the location of the crack, and the amplitude of the echo indicates its

size.

The NIST team has developed

a version of the EMAT sensor that can be mounted right in the rail.

28
That would permit each wheel to be inspected on the move, as it

rolls over the sensor. Tests at the

FRA facility near Pueblo, Colo.,

showed that the system works on

trains traveling up to 15 miles per

hour. Work continues on the system to improve its ruggedness for long-term use in exposed rail

yards.

The NISTteam has

developed a version

of the EMAT sensor

that can be mounted

right in the rail.

A similar problem is that the

heat of braking also can cause

stress which adds to the residual

tensile stresses from manufacturing, and eventually tiny cracks in

the rim may grow and cause the

wheel to fracture.

It's the job of railroad inspectors to see that wheels are in- spected regularly and, if necessary, removed from service

before they break and cause an

accident. Despite the inspectors'

efforts, according to the FRA, rail- road wheel failures caused 134

accidents totaling $27.5 million in damages over the past 4 years.

Visual inspection can spot

characteristic rust patterns on the

sides of wheels that indicate the

wheel has been overheated by

heavy braking—a condition that

may result in high stress levels. But this visual rust-pattern

method has a very high error rate;

Dragan Mitrakovid (left), a guest researcher from the University of Belgrade, and NISI physicist

Raymond Schramm inspect railroad wheels using an EMAT sensor mounted in a typical rail.

about half the wheels removed

from service turn out to have ac- ceptably low stress levels when

tested in the shop. This means

that a lot of money is wasted in removing safe wheels.

When cracks in the tread, the

part of the wheel that touches the

rail and bears the weight of the

train, are large enough, they too can be seen. But visually inspecting for such cracks is tedious, difficult, and not totally reliable

inspectors can miss some cracks

that, while apparently small, actually have reached a dangerous

size.

To detect this condition,

polarized sound waves, which vibrate in certain directions and not

in others, are passed through the

wheel's rim. The velocity of the waves changes in proportion to

the amount of residual stress in

the rim. Measuring the sound

velocity in different directions

through the wheel can give an indication of the relative amounts of

stress both across the rim and

around the circumference. NIST

is developing an EMAT system

for this task, as well. When the work is done, the nation's railroads will have two new

tools to increase safety and

decrease costs.

by Collier Smith

NIST Public Affairs Specialist

29
NewPublications

Cooperative Research

Opportunities at NIST

Natl. Inst. Stand. & Tech. (U.S.), NIST

Spec. Pub. 763, 56 pages (October

1989). Order by sending a self- addressed mailing label to Office of Technology Commercialization, A343 Physics

BIdg., NIST, Gaithersburg, MD 20899.

Almost from the day its doors

opened in 1901 as the National

Bureau of Standards, NIST scientists and engineers have been working

with their counterparts in industry, trade

associations, universities, and other

government agencies to come up with

real-world solutions for real-world problems. The research partnerships with

NIST can take many forms ranging from one scientist working with another on a

specific problem to hundreds of organizations collaborating to develop new technology that will benefit many. Some of

these joint programs last years, others

months or weeks. The goal is to solve a problem efficiently, effectively, and as

quickly as possible. NIST is willing to work with any organization that has a

stake in helping U.S. business compete

more effectively. This brochure describes briefly a sampling of almost 200

NIST research projects in which NIST

would welcome collaboration with scientists and engineers from industry, universities, and other government agencies.

Directory of U.S. Private Sector

Product Certification Programs

Breitenberg, M., editor, Natl. Inst. Stand.

& Tech. (U.S.), NIST Spec. Pub. 774, 235

pages (December 1989). Order by stock

no. 003-003-02984-0 from GPO, $12

prepaid.

The programs and activities of 132

private-sector groups that provide

product certification services are cataloged in this new revision. The directory is designed to serve the needs

of federal agencies and standards writers, as well as product manufacturers,

engineers, purchasing agents, distributors, and others concerned with productrelated certification procedures. The

listings describe type and purpose of

each U.S. -based group, products

certified, standards used, certification re- quirements, any accreditation or recognition by a U.S. or foreign private-sector or government agency, availability of sen/-

ices, and method used to determine cost

of services. Information is indexed by or- ganizational name, acronyms and initials, and by products certified.

NIST Standard Reference

Materials Catalog 1990-91

McKenzie, R.L., editor, Natl. Inst. Stand.

&Tech. (U.S.), NIST Spec. Pub. 260, 161

pages (January 1990). Order by sending a self-addressed mailing label to Office

of Standard Reference Materials, Rm.

204 BIdg. 202, NIST, Gaithersburg, MD

20899.

This catalog lists approximately

1 ,100 Standard Reference Materials (SRM's) available from the

Institute. Materials certified for their

chemical and physical properties include

cements, ores, metals, glass, plastics,

food, and environmental standards. Also

certified are nutrition and clinical health

standards to calibrate instruments that measure marijuana and cholesterol in human urine and serum, fat-soluble vi- tamins and cholesterol in food products,

and levels of the enzyme aspartate

aminotransferase (AST) to detect heart

attacks. The catalog contains an alphabetical index and a complete numerical

listing of the latest renewal SRM's and

their certificate dates. Prices for the

SRM's are published separately in annual supplements.

Standard Reference Data

Publications 1987-1989

Sauerwein, J.C., Natl. Inst. Stand. &

Tech. (U.S.), NIST Spec. Pub. 708,

Suppl. 2, 52 pages (December 1989).

Order by sending a self-addressed mailing label to Standard Reference Data

Program, A323 Physics BIdg., NIST,

Gaithersburg, MD 20899.

The Standard Reference Data Pro- gram, which evaluates data on the

physical and chemical properties

of substances, is an important part of

NIST's measurement services program

for science and industry. This publication

updates the 1964-1984 directory of publications and computerized databases

prepared through the National Standard

Reference Data System (NSRDS) established in 1963. The supplement contains

new information on reprints and supplements from the Journal of Physical and

Chemical Reference Data, other NSRDS

data compilations, critical bibliographies

and indexes from other publishers, and

databases available in printed form, on

magnetic tape, disks, and through online computer networks.

Quick Response Sprinklers in

Chemical Laboratories:

Fire Test Results

Walton, W.D., Natl. Inst. Stand. & Tech.

(U.S.), NISTIR 89-4200, 55 pages

(November 1989). Order by stock no. PB

#90-151 721/AS from NTIS, $17 prepaid.

During a fire in a chemical laboratory, lives and property as well as

critical scientific experiments are

at risk within seconds. Researchers at NIST conducted a series of full-scale fire

tests in chemical labs to examine the

potential of quick response sprinklers to improve life safety and protect property.

The tests were part of a project to help

the National Institutes of Health develop

sprinkler design criteria for its chemical

30
labs. In an unsprinklered laboratory, the

NIST researchers found that within 38

seconds all of the combustible material

in the lab was burning, creating lethal conditions and extensively damaging the

laboratory. In contrast, both the standard

and quick response sprinklers effectively

controlled the fires and reduced temperatures as well as carbon monoxide and

carbon dioxide levels.

Intelligent Processing

for Primary Metals

Cramb, A., Eckhart, Jr., W.E.,

Watanapongse, D., et al., editors, Natl.

Inst. Stand. & Tech. (U.S.), NIST Spec.

Pub. 772, 40 pages (November 1989).

Order by sending a self-addressed mailing label to James Early, B309 Materials

BIdg., NIST, Gaithersburg, MD 20899.

This report summarizes the re- search agenda for the intelligent

processing of steel, which was

developed at a workshop sponsored by

NIST, the Department of Energy, and the

American Iron and Steel Institute (AISI).

The agenda was developed after officials from industry, universities, and

government defined the key elements

producers need for the intelligent processing of steel, assessed the status of

available technologies, and outlined

strategies for implementing their use. Experts at the workshop recommended applying intelligent processing concepts in three generic areas: production and refining of primary metal (iron, steel, and

aluminum), production of near-net shape

products, and the finishing and coating

of metals to yield final properties. The

findings have been reviewed by an AISI

advisory committee, which recom- mended that priorities be determined

and a long-term research program be

established with an industry consensus.

NIST Reactor: Summary

of Activities—July 1988 Through

June 1989

O'Connor, C, editor, Natl. Inst. Stand. &

Tech. (U.S.), NIST Tech. Note 1272, 324

pages (December 1989). Order by stock

no. 003-003-02980-7 from GPO.

The NIST reactor serves the needs

of NIST, other government agencies, universities, and industries as a national center for the application of

neutron methods to a broad range of

problems of national interest. Operating

at 20 MW, the reactor supports over 25

research facilities, with an additional 15

becoming available over the next 3 years as part of the cold neutron project.

During the period covered by this report, over 1,160 irradiations were performed,

and more than 350 researchers used the

facilities. Programs range from the use of

neutron beams to study the structure and

dynamics of materials through nuclear

physics and neutron standards to sample irradiations for activation analysis, isotope production, neutron radiography, and nondestructive evaluation.

Mr iiriifBllflMii^^

1990 Directory of NVLAP

Accredited Laboratories

Trahey, N.M., Horlick, J., and White, V.R.,

Natl. Inst. Stand. & Tech. (U.S.), NISTIR

90-4280, 69 pages (March 1990). Order

by stock no. PB #90-198920/AS from

NTIS, $17 prepaid ($8 microfiche).

This publication lists nearly 900

domestic and foreign laboratories

that are accredited by the NIST

National Voluntary Laboratory Accreditation Program (NVLAP) for specific test methods as of March 1 , 1990. The current fields of testing are acoustics; asbestos fiber analysis; carpet; commercial

products—paint, paper, plastic, and

seals and sealants; computer applications; construction testing services—concrete, cement, aggregates, soil and rock,

admixtures, geotextiles, road and

paving; electromagnetic compatibility

and telecommunications; personnel

radiation dosimetry; solid fuel room

heaters; and thermal insulation.

Integrating Knowledge for the

Identification of Cracks in

Concrete Using an Expert System

Shell and Extensions

Kaetzel, LJ., Clifton, J.R., and Bentz,

D.P., Natl. Inst. Stand. & Tech. (U.S.),

NISTIR 89-4206, 34 pages (December

1989). Order by stock no. PB #90-

151234/AS from NTIS, $15 prepaid.

Remember the children's ditty,

"Step on a crack, break your

mother's back?" While that's not

true, cracks in concrete structures are nothing to sing about. To help diagnose

the causes of cracks in concrete, NIST

researchers have developed a prototype

expert system known as "CRACKS." An

expert system is a computer program

that incorporates facts along with experts' opinions and guidelines. In addition, CRACKS includes a database for maintaining information describing a

structure and an "image base" for storing

digitized photographs and drawings of

cracking. CRACKS also can be used to measure the rate of deterioration of a

structure by comparing observations over time. While CRACKS is not yet available commercially, it is available for re- view and comment. This report

describes the system.

Ordering Information

To order publications from NTIS, send

the request with payment to: National

Technical Information Service, Springfield, VA 221 61 . Publications can be

ordered from GPO by mailing the order

with payment to the Superintendent of Documents, U.S. Government Printing

Office, Washington, DC 20402.

31
Conference Calendar

July 23-25, 1990

Conference on Advances

in Cementitious Materials

NIST, Gaithersburg, MD

Enhancing the performance of concrete can make it a more predictable material.

The purpose of this conference is to ad- vance understanding of cementitious materials to provide a rational approach to the design of new cementitious materials

and composites. The fundamental

science underlying the behavior of all cementitious materials will be addressed;

however, to limit the scope of the conference, degradation processes will not be

included. Session topics include characterization of particulate starting materials

and of resultant microstructure; physical

and chemical phenomena in the flow of

cementitious materials prior to hardening; relationships between microstructure

and physical and mechanical uehavior;

and interactions of water with the hardened cement paste matrix. Participants

will be able to visit the laboratories of the

NIST Center for Building Technology.

Sponsored by NIST and the American

Ceramic Society. Contact: Geoffrey

Frohnsdorff, B368 Building Research

BIdg., NIST, Gaithersburg, MD 20899,

301/975-6706.

August 6-9, 1990

North American ISDN Users'

Forum (NIU-Forum)

NiST, Gaithersburg, MD

Integrated Services Digital Network

(ISDN) is a telecommunications technology which can be used to send and

receive voice, data, and pictures simultaneously over digital telephone lines. But, for this technology to develop, user- defined applications, implementation

agreements for the existing standards,

and tests are needed to allow for a transparent, ubiquitous, and user-driven

ISDN. NIST has formed—with private in- dustry (both manufacturers and prospective users of ISDN technology)—a forum

to find ways to promote the implementation of ISDN standards in interoperable

products and services, and to identify

potential ISDN applications. This meeting

of the forum will consist of tutorials, lab

tours, demonstrations, seminars, and

joint workshops for the users and implementors of ISDN technology. Sponsored

by NIST. Contact: Dawn Hoffman, B364

Materials BIdg., NIST, Gaithersburg, MD

20899, 301/975-2937.

August 17-22. 1990

International Conference

on the Chemistry of Electronic

Ceramic Materials

Sojourner Inn, Teton Village, Jackson, WY

Materials chemistry has evolved from the more identifiable disciplines of inorganic

and solid state chemistry, ceramics, and

materials science. This conference will bring together major national and inter- national researchers to bridge the gap

between those primarily interested in the

pure chemistry of inorganic solids and

those interested in the physical and electronic properties of ceramics. One of the

primary goals of the conference will be to evaluate the current understanding of the

chemistry of electronic ceramic materials

and to assess the state of a field that has

become one of the most important areas

of advanced materials research. Sponsored by NIST, the Office of Naval Research, and NASA. Contact: Robert Roth,

B126 Materials BIdg., NIST, Gaithersburg, MD 20899, 301/975-6116.

September 18-20, 1990

Electronic Publishing '90

NIST, Gaithersburg, MD

This will be the third in a series of inter- national conferences established to bring

together researchers in all areas of electronic publishing systems. EP90 will adopt a broad definition of "electronic

publishing," encompassing all aspects of

computer-assisted preparation, presentation, transmittal, storage, and retrieval of

documents. The scope of the conference

also includes the design of the related

computer systems, the design of their

components, and the theory that underlies such systems. The proceedings will be published in book form and will be

available at the conference. Sponsored

by NIST. Contact: Lawrence A. Welsch,

B252 Technology BIdg., NIST, Gaithersburg, MD 20899, 301/975-3345.

October 1-4, 1990

13th National Computer Security

Conference

Omni Shoreham Hotel, Washington, DC

This conference provides a forum for the

government and the private sector to share current information that is useful

and of general interest to the conference

participants on technologies, present

and future, that are designed to meet the

ever-growing challenge of telecommunications and automated information

systems security. The focus of the confer- ence will be on: systems application

guidance; awareness, training, and education; ethics; evaluation and certification; innovations and new products;

management and administration; and

disaster prevention and recovery. Sponsored by NIST and the National Computer Security Center. Contact: Irene

Gilbert, A21 6 Technology BIdg., NIST,

Gaithersburg, MD 20899, 301/975-3360.

32

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