Technology at a Glance is a quarterly newsletter from the National Institute of Standards and Technology reporting on research results, funding programs, and manufacturing extension and technology services. If you have comments or general questions about this newsletter or if you would like to receive the four-page, color newsletter in hard copy, please email your mailing address to Gail Porter, editor, or call (301) 975-3392. About Technology at a Glance.
rings suddenly have new cachet, and it has nothing to do with the
price of gold or trends in marriage. Moreover, in this case, smaller
rings are better.
NIST scientists and collaborators have demonstrated that when a gold ring has a radius of about 60 nanometers, it acquires special properties that could make it a useful container for nanoscale experiments that would provide unusually clear results. Such experiments would be of interest to the drug industry and biochemical researchers, among others.
nanoparticles are attracting research interest because they
and emit certain types of light very efficiently, depending on particle
size and shape. In a recent paper, NIST physicists and collaborators
in Sweden and Spain documented that gold nanorings have unique optical
and electromagnetic properties that can be tuned by
varying the ratio of the ring radius and wall thickness.
light is directed at the ring, it excites the electrons at the metal
and creates a wave that oscillates in certain ways depending on the
wavelength of light and ring geometry. The effect is similar to that
of wind hitting a swimming pool, where the resulting wave movement
depends on wind velocity and pool shape. The NIST team determined
how to synchronize the energy of the incoming light and the pool of
electrons, so that they resonate on the same wavelength.
resonance creates a strong and spatially uniform electromagnetic field
that oscillates inside the ring cavity. The figure above depicts the
field within and around a ring with a radius of 60 nm and a wall thickness
of 10 nm. The colors indicate the field strength, ranging from blue
(weak) to green and yellow (strong and uniform) to red (very strong).
The arrows indicate the direction of the field created by the pool
of excited electrons.
field inside a ring with these dimensions is optimized for the near-infrared
part of the electromagnetic spectrum. The ring cavity could, therefore,
be a useful container for experiments in which molecules are tested
with light, because it would amplify infrared signals. For example,
researchers study the chemical bonds in biomolecules like proteins
by probing them with lasers and detecting how much of the light is
absorbed and re-emitted at specific frequencies. By conducting such
experiments inside a nanoring, researchers could obtain amplified
infrared signals and clearer results.
Contact: Javier Aizpurua, (301) 975-8560, firstname.lastname@example.org.
NIST has launched
an investigation into the tragic fire at The Station nightclub in
West Warwick, R.I. The work is being conducted under the authorities
of the National Construction Safety Team (NCST) Act. NIST is working
with a team of public and private-sector fire and safety experts to
carry out the
Under the act,
NIST is responsible for conducting fact-finding investigations of
building-related failures that result in substantial loss of life.
The teams primary objectives are to:
The NIST investigation
is being conducted in close cooperation with other federal and private-sector
agencies, as well as state and local fire and law enforcement agencies.
The decision to
launch the NIST investigation was made following an onsite evaluation
conducted by two NIST fire researchers and discussions with other
investigators on the scene in Rhode Island.
The NIST investigation
could result in recommendations for specific changes to building codes,
standards, and practices.
with the NCST Act, any report resulting from the investigation can
not be admitted as evidence or used in any suit or action for damages
related to the nightclub fire. In addition, NIST employees are not
permitted to serve as expert witnesses.
For more on the NCST, go to www.nist.gov/public_affairs/factsheet/constructionact.htm.
smaller and ever faster. The pursuit of nanotechnologychips,
sensors, pumps, gears, lasers, novel materials, and an unending assortment
of other useful things with features on the scale between
one-billionth of a meter (about 10 hydrogen atoms across) and 100-billionths
of a meteris driving science and engineering to extremes.
A recently launched
Web site, www.nist.gov/nanotech,
details work under way at NIST, where research truly is pushing the
limits of technology. NIST scientists and engineers are building atom
and electron counters, single-photon turnstiles, ultracold ion and
atom traps, and lasers that generate uniform pulses of light that
last only a few trillionths of a second.
Web site explains how NISTs seven major laboratories are developing
measurements, standards, and data crucial to private industrys
development of products for a nanotechnology market that could reach
$1 trillion during the next decade. Topics covered on the Web site
include: NIST and the National Nanotechnology Initiative; fundamental
science and basic measurement capabilities; characterization of nanostructured
materials; nanoscale electronics, optoelectronics and magnetics; nanochemistry
and nanobiotechnology; and quantum computing and communications. Theres
even a just-for-fun quiz, Whats
Your Nano IQ?
A separate Web
features a more in-depth look at NIST research on quantum information
Contact: Barbara Goldstein, (301) 975-2304.
oceans may look a bit bluer than they did before in satellite imagesmeaning
there may be less carbon or biomass in the oceans than previously
thoughtas a result of recent measurement corrections made possible
by a unique NIST-designed instrument.
instrument, called the traveling SIRCUS, was transported
to Hawaii last year to calibrate marine buoys that measure the color
and magnitude of light reflected from and within the ocean. Data from
these buoys are used to calibrate instruments on satellites that map
the color of the Earths oceans. Ocean color is important in
climate research because variations in the visible light region of
the spectrum reflect the concentration of microscopic marine plants,
which absorb carbon from the ocean and atmosphere for photosynthesis.
These phytoplankton absorb blue light and reflect predominantly green
light, whereas pure water reflects predominantly blue light.
traveling SIRCUS (a miniature version of NISTs Spectral
Irradiance and Radiance Calibrations with Uniform Sources facility)
resolve discrepancies in the buoys measurements of blue light
and corrected errors caused by stray light. The stray light corrections
resolved a major measurement problem in the buoy systems and increased
confidence in the overall results. The laser-based instrument offers
unique calibration capabilities, not only because it is portable
but also because it can be tuned to produce intense light of any
color (or wavelength), across the ultraviolet, visible, and near-infrared
parts of the spectrum.
are having an impact on scientists calculations of the
biomass and carbon concentrations in the oceans, which will
provide a more
accurate understanding of Earths carbon balance and its effect
on climate. Initial estimates using SIRCUS results suggest that
biomass (as measured by chlorophyll concentrations) may be about
6 percent lower than previously thought.
was a collaboration between NIST and the National Oceanic and Atmospheric
Administration, with additional funding from the National Aeronautics
and Space Administration.
Contact: Steven Brown, (301) 975-5167.
FY 2003 Funding Approved
in the FY 2003 budget are: $351.9 million for the NIST Laboratories;
$5.2 million for the Baldrige National Quality Program; $178.8 million
for the Advanced Technology Program; $105.9 million for the Manufacturing
Extension Partnership; and $65.7 million for Construction of Research
Facilities. The last category includes high priority safety, capacity,
maintenance and major repair projects; construction and renovation
projects at NISTs Boulder, Colo., laboratories; and moving costs
and final lab adjustments for the nearly complete NIST Advanced Measurement
Laboratory in Gaithersburg, Md.
For more information see: www.nist.gov/public_affairs/budget.htm.
Mixing ingredients for a cake or a batch of cookies is a pretty simple matter. Mixing in industry is often more difficult. For example, mixing a gas into a liquid is typically a complicated procedure. Now, NIST researchers have developed a new device that can do the job in a matter of seconds rather than hours. Developed to improve measurements for the gas industry, the new mixer uses a hollow rotor shaped like a double helix. The rotor is placed in a closed container filled with the desired liquid and gas is pumped through it. An external magnetic field spins the rotor and the gas circulates through strategically placed holes, allowing quick distribution throughout the liquid. The new mixer also has been used for facilitating chemical reactions and for extractions such as removing heavy metals from water, an application with important environmental implications. The research team will continue to develop new applications for the mixer. A patent is pending. Contact: Thomas Bruno, (303) 497-5158, email@example.com.
Theres a relatively new weapon in the battle against illicit drug usehair. Unlike urine or other body fluids, hair tissue retains traces of cocaine and other drugs for at least 90 days (not just two or three). Hair also is easier to collect and harder to switch or contaminate. As a result, hair analysis increasingly is used to screen job applicants, athletes, and others for illicit drug use. The accuracy of such tests now can be checked through the use of two new NIST Standard Reference Materials (SRMs). The standards consist of human hair segments that have been soaked in solutions containing target drugs and then carefully measured for drug concentrations. SRM 2379 is designed for calibrating tests of stimulants (uppers) such as cocaine and PCP, while SRM 2380 helps check tests for depressants (downers), such as codeine and THC (the active ingredient in marijuana). Drugs usually are not detectable in hair samples until 10 days after use, so hair analysis is likely to complement rather than completely replace traditional screening methods. Contact: Michael Welch, (301) 975-3100.
When the 150-year-old dome of the U.S. Capitol began leaking during heavy rainstorms a few years ago, the Office of the Architect of the Capitol asked NIST welding experts for help. Their daunting request: return the cast-iron supporting structure of the domes outer shell to its original condition without replacing the cracked castings or losing any of the iron works historical integrity. An initial attempt in 1998 failed when the test welds cracked. NIST engineers went back to the drawing board (and the lab) to develop and test other options. The best-working technique turned out to be oxyacetylene braze welding (a flame repair process where the filler metal melts at a temperature below that of the casting) combined with a copper-zinc alloy called low-fuming bronze. The bronze forms joints that are very similar in strength to the original castings. NISTs experts have submitted their recommendation to the Architects office. Contact: Thomas Siewert, (303) 497-3523, firstname.lastname@example.org.
Pulsed lasers are like middle schoolers at a dance. You can put them in the same physical space, but they still dont pair up very well. Recently, however, NIST researchers at JILA (a joint institute of NIST and the University of Colorado) have coaxed ultrafast pulsed lasers with different wavelengths not only to match the timing of their pulses but also to lock into the same phase, or cycle of peaks and troughs. To extend the analogy, theyve made unruly, ultrafast lasers do the equivalent of two middle schoolers moving in perfect synchrony like Olympic ice dancers. The technique provides an important new tool for studying the motions and vibrations of atom groups within molecules. By synchronizing and locking the wave forms of two sub-picosecond lasers together, they have made a well-controlled, tunable source of infrared radiation that can be used to precisely break specific bonds or produce specific rotational or vibrational changes in large molecules. The technique also may be useful for transmitting ultraprecise frequency signals or for mapping the chemical composition of living cells with pulses so quick they dont damage the living tissue. Contact: Jun Ye, (303) 735-3171, Ye@jila.colorado.edu.
Fire SafetyCarelessly dropped cigarettes are the largest single cause of U.S. fire deaths. To help combat this problem, New York soon will become the first state to require that cigarettes sold in the state meet a standard that limits their ability to start furniture or bed fires. The test method, issued by ASTM International, was developed by NIST in 1993 and refined in 2002. ASTMs standard test method is available at www.astm.org. The NIST report, Test Methods for Quantifying the Propensity of Cigarettes to Ignite Soft Furnishings, is available at http://fire.nist.gov/bfrlpubs. Contact: Richard Gann, (301) 975-6866.
Health InformationNIST information security experts are teaming up with URAC, also known as the American Accreditation Health Care Commission, to identify best practices for information security in health care. The Security Health Care Certification and Accreditation Workgroup is reviewing draft security guidelines recently published by NIST and the new security rules being phased in under the Health Insurance Portability and Accountability Act of 1996. Ultimately, the group hopes to develop a common set of health care security standards that will cover security policies, procedures, controls and auditing practices. Contact: Arnold Johnson, (301) 975-3247.
Cancer DetectionResearchers from NIST and the University of Wisconsin-Madison are developing technology that may lead to more accurate methods of detecting and diagnosing breast tumors. The team is using a characterized coaxial probe to measure the electric and magnetic properties of healthy human breast tissue. The development of this technology is an important first step toward the future use of such probes to distinguish between healthy tissue and malignancies based on these properties. Contact: Christopher Holloway, (303) 497-6184, email@example.com.
NIST is an agency of the US Department of Commerce's Technology Administration. NIST develops and promotes measurement, standards, and technology to enhance productivity, facilitate trade, and improve the quality of life. Technology at a Glance is produced by Public and Business Affairs, NIST, 100 Bureau Dr., Stop 3460, Gaithersburg, Md. 20899-3460. Any mention of commercial products is for information only; it does not imply recommendation or endorsement by NIST. Technology at a Glance Editor: Gail Porter, (301) 975-3392, email: firstname.lastname@example.org. For patent information, call (301) 975-3084.