NIST Tech Beat - May 25, 2006

This week the National Institute of Standards and Technology (NIST) awarded grants totaling $4.5 million to five organizations affiliated with NIST’s Hollings Manufacturing Extension Partnership (MEP) to assist manufacturers in Gulf Coast regions hard hit by last year’s hurricanes.

“Smaller manufacturers are critical to the competitiveness of the entire manufacturing sector and to the health of the U.S. economy. This funding to MEP-affiliated centers in the Gulf Coast region will help manufacturers whose businesses were affected by last year’s hurricanes recover and rebuild,” said Roger Kilmer, director of NIST’s MEP at the 2006 MEP National Conference in Orlando, Fla., on May 23.

The funding is going to the Mississippi Technology Alliance and Manufacturing Extension Partnership of Louisiana ($2.2 million for a joint project), the Alabama Technology Network ($750,000), the Texas Manufacturing Assistance Center ($800,000) and the Florida Manufacturing Extension Partnership ($750,000). A top priority for the five MEP centers is to help manufacturers find workers and restore operations to pre-hurricane levels. Other goals are to help manufacturers locate and obtain private-sector resources to help with facility reconstruction, provide financial and contingency planning, and incorporate technology and automation into the workplace. The centers will collaborate with each other and with numerous other partners, including universities and economic development agencies.

MEP is a nationwide network of resources transforming manufacturers to compete globally, supporting greater supply chain integration, and providing access to technology for improved productivity.

Researchers at the National Institute of Standards and Technology (NIST) have developed an improved method for measuring basic properties of complex fuel mixtures like gasoline or jet fuel. The new apparatus for measuring distillation properties produces significantly more detailed and accurate data needed to better understand each fuel and its sample-to-sample variation. The data are valuable in tailoring fuels for high-performance and low emissions, and in designing new fuels, engines and emission controls.

Petroleum-based fuels, with few exceptions, are highly complex mixtures of hundreds of distinct components from light butanes to increasingly heavy oils. For decades, distillation curves have been one of the most widely accepted ways of characterizing a fuel. The curve charts the percentage of the total mixture that has evaporated as the temperature of a sample is slowly heated. The curve holds a wealth of information—not just the basic makeup of the fuel, but also indicators as to how it will perform. Engine starting ability, fuel system icing, vapor lock, fuel injection scheduling, fuel auto-ignition, hot- and cold-weather performance, and exhaust emissions all have been correlated with features of the distillation curve. The data are important both for quality control at refineries and the design of specialty high-performance fuels.

For all its utility, there are serious problems with the common method for measuring a distillation curve in industry, based on an old ASTM standard called D-86. The method is subject to large uncertainties and systematic errors that make it difficult or impossible to relate the test results to thermodynamic theory used in developing modern fuels and engines. NIST researchers added an additional temperature sensor and made other modifications, decreasing the random uncertainty in the temperature measurement and control from a few degrees to 0.05 degree and eliminating a number of systematic errors. They also added the capability to do a composition analysis of each boiling “fraction,” which can provide vital insights into fuel behavior and pinpoint batch-to-batch differences to help diagnose production problems.

The nano world is getting brighter. Nanowires made of semiconductor materials are being used to make prototype lasers and light-emitting diodes with emission apertures roughly 100 nm in diameter—about 50 times narrower than conventional counterparts. Nanolight sources may have many applications, including “lab on a chip” devices for identifying chemicals and biological agents, scanning-probe microscope tips for imaging objects smaller than is currently possible, or ultra-precise tools for laser surgery and electronics manufacturing.

Researchers at the National Institute of Standards and Technology (NIST) are growing nanowires made of gallium nitride alloys and making prototype devices and nanometrology tools. The wires are grown under high vacuum by depositing atoms layer by layer on a silicon crystal. NIST is one of few laboratories capable of growing such semiconductor nanowires without using metal catalysts, an approach believed to enhance luminescence and flexibility in crystal design. The wires are generally between 30 and 500 nanometers (nm) in diameter and up to 12 micrometers long. When excited with a laser or electric current, the wires emit an intense glow in the ultraviolet or visible parts of the spectrum, depending on the alloy composition.

A paper in the May 22 issue of Applied Physics Letters* reports that individual nanowires grown at NIST produce sufficiently intense light to enable reliable room-temperature measurements of their important characteristics. For example, the peak wavelength of light emitted with electric field parallel to the long axis of a nanowire is shifted with respect to the peak wavelength emitted with electric field perpendicular to the wire. Such differences in emission are used to characterize the nanowire materials and also may be exploited to make sensors and other devices.

NIST has grown a variety of nanowires and extensively characterized their structural and optical properties, finding few defects, strains or impurities, which results in high light output compared to the bulk material.** The wires also can be transferred from the silicon crystal to other substrates, such as sapphire, and arranged using electric fields. The NIST team has used the nanowires to make a number of prototype devices, including light-emitting diodes, field-effect transistors, and nanowire “bridge” structures that may be useful in sensors and nanoscale mechanical resonators.

*J.B. Schlager, N.A. Sanford, K.A. Bertness, J.M. Barker, A. Roshko and P.T. Blanchard. 2006. Polarization-resolved photoluminescence study of individual GaN nanowires grown by catalyst-free MBE. Applied Physics Letters. May 22.

An improved technique for culturing cells, developed at the National Institute of Standards and Technology (NIST), may enable new, fundamental insights into the behavior of neuronal cells.

Culturing particular types of cells in isolation is a basic technique for measuring how they respond to various stimuli, testing new drugs, and similar cell biology tasks. Neuronal cells, which make up the central nervous system in mammals, are both particularly important and particularly hard to culture. They are highly specialized and choosy about their environment—normally they only survive and develop when cultured on a layer of non-neuronal “glial” cells that provide cellular support services. There are usually far more glial cells than neuronal cells, which makes it hard to image neuronal cells and measure their activity against the glial background.

In a paper in the American Chemical Society’s journal Langmuir*, NIST researchers detail a microfluidics technique to culture neuronal cells in relative isolation on a variety of cell-culture surfaces, and to pattern the cells on the surface to study the effects of geometry on cell development. The trick is to mask the substrate with multiple alternating layers of positively and negatively charged polymers, building up a so-called polyelectrolyte multilayer (PEM). Properly selected, the PEM coating convinces the neuronal cells that they’re in a good environment to attach, develop and produce the characteristic neuron projections and synapses, all without a glial layer.

Even better, according to the NIST team, microfluidic channels can be used to lay down the PEM coating in patterned lines just a few micrometers wide. Neuronal cells will largely confine themselves to the pattern, enabling a variety of cell-geometry experiments, such as measuring the maximum gap between lines that can be bridged by neural axons and dendrites.

The research is part of a multidisciplinary NIST program to develop biochemical measurement technologies based on microfluidics.

*S.P. Forry, D.R. Reyes, M.Gaitan, and L.E. Locascio. Facilitating the culture of mammalian nerve cells with polyelectrolyte multilayers. Langmuir, ASAP Article Web Release Date: May 19, 2006. Available at: http://pubs.acs.org/cgi-bin/abstract.cgi/langd5/asap/abs/la053244b.html.

The National Institute of Standards and Technology (NIST) will host a national Options for Action Summit to devise ways to strengthen U.S. efforts that help developing nations build their economies and, in tandem, foster their adoption of standards that ensure fair market access for U.S. exports.

Co-sponsored by NIST and the American National Standards Institute (ANSI), the conference is open to representatives of industry, standards organizations and government. It will be held July 18-19, 2006, at the NIST campus in Gaithersburg, Md.

First-day sessions will include trading partners’ assessments of U.S. standards-setting activities, provided by government or industry representatives from China, Egypt, the European Union, Japan and Mexico. Panelists will give their views on how the United States has performed in efforts to advance a global standards agenda.

The opening session will review the U.S. Standards Strategy, the National Export Strategy and the Commerce Department’s Standards and Competitiveness Initiative. Speakers also will survey relevant outreach, education, and technical assistance efforts sponsored by federal agencies and by U.S. businesses and trade organizations.

Besides NIST and ANSI, other organizations invited to participate in conference sessions include the National Association of Manufacturers, U.S. Trade Representative’s Office, International Trade Administration and World Bank.

Breakout sessions will concentrate on current U.S. outreach and capacity-building initiatives in specific regions. Discussions will focus on identifying best practices, “do’s and don’t’s,” and activities that deserve more attention. These sessions will yield recommendations for steps intended to coordinate and improve standards harmonization, ensure market access for U.S. goods and services, and increase the effectiveness of capacity building and technical assistance efforts. The objective is to achieve consensus on a consolidated set of “options for action.”

The registration deadline is July 7. To register or for more information on the Options for Action Summit, go to www.ansi.org/events.

Three Nobel Laureates from the National Institute of Standards and Technology (NIST), William Phillips (1997), Eric Cornell (2001), and John Hall (2005), testified on their physics research and their personal views on science policy on May 24 at a hearing before the House Science Subcommittee on Environment, Technology, and Standards. Copies of their prepared remarks are available at http://www.nist.gov/testimony/06index.html.

Registration is now open for the Biometrics Consortium Conference 2006, one of the nation’s largest conferences featuring the latest advances in research, development, testing, standardization and application of biometric technologies. The conference will be held Sept. 19-21, 2006, in Baltimore, Md. More than 1,000 people attended last year’s conference which featured more than 100 speakers and more than 70 exhibits. For more information and to register online, go to http://www.nist.gov/public_affairs/confpage/060919a.htm.

Non-profit organizations considering applying for the Malcolm Baldrige National Quality Award in 2007 or using the Baldrige criteria for performance excellence may be interested in an application for the award from a fictitious government organization, the “Flagstaff District of the U.S. Water Resource Agency.” Starting in 2007, non-profit organizations—including charities, trade and professional associations, and government agencies—will be eligible to apply for the Baldrige Award.

The application was developed to help non-profit organizations better understand the Baldrige criteria for performance excellence and how it applies to them and to illustrate what an application for the award might look like. It also will be used to help train members of the private-sector board of examiners who review applications for the Baldrige Award. The application and evaluation process for the Baldrige Award is rigorous and thorough and has been called one of the most cost-effective and comprehensive performance assessments available anywhere. The application is available at http://baldrige.nist.gov/Flagstaff.htm.

Researchers at the National Institute of Standards and Technology (NIST) recently added 150 new methods—nicknamed “recipes”—to a database already containing 255 procedures for analyzing specific synthetic polymers using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The recipes provide data critical to the industrial design, manufacture and application of synthetic polymers. They have been collected from the peer-review scientific literature and included in the NIST Synthetic Polymer MALDI Methods Online Database, http://www.nist.gov/maldi, a unique resource for the mass spectroscopy community. The recipes Web page has been extremely successful—it is listed as the most popular mass spectrometry site on the Web by Websbiggest.com and has been cited as a key chemistry resource by the Journal of the American Chemical Society.

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Editor: Michael Baum

Date created: 5/24/06
Date updated: 5/24/06
Contact: inquiries@nist.gov