Journal of Research of the National Institute of Standards and Technology articles from July 2003

Journal of Research of the National Institute of Standards and Technology archives from July 2003

Note to readers.(Editorial)
July 1, 2003... Dear Reader, With this issue, we begin a new feature in the Journal of Research of the National Institute of Standards and Technology. The article, "Review of Instrumented Indentation," by Mark VanLandingham is the first in a series of...

Review of instrumented indentation.
July 1, 2003... Instrumented indentation, also known as depth-sensing indentation or nanoindentation, is increasingly being used to probe the mechanical response of materials from metals and ceramics to polymeric and biological materials. The additional levels...

Towards high accuracy reflectometry for extreme-ultraviolet lithography.
July 1, 2003... Currently the most demanding application of extreme ultraviolet optics is connected with the development of extreme ultraviolet lithography. Not only does each of the Mo/Si multilayer extreme-ultraviolet stepper mirrors require the highest...

Virtual environment for manipulating microscopic particles with optical tweezers.
July 1, 2003... In this paper, virtual reality techniques are used to define an intuitive interface to a nanoscale manipulation device. This device utilizes optical methods to focus laser light to trap and reposition nano-to-microscopic particles. The...

On the stability of exponential backoff.
July 1, 2003... Random access schemes for packet networks featuring distributed control require algorithms and protocols for resolving packet collisions that occur as the uncoordinated terminals contend for the channel. A widely used collision resolution...

A link-level simulator of the cdma2000 reverse-link physical layer.
July 1, 2003... The cdma2000 system is an evolutionary enhancement of the IS-95 standards which support 3G services defined by the International Telecommunications Union (ITU). cdma2000 comes in two phases: 1XRTT and 3XRTT (1X and 3X indicates the number of...

NIST-developed wideband sampling voltmeter provides increased accuracy to calibration laboratory customers.(General Developments)(Brief Article)
July 1, 2003... A wideband (10 Hz to 1 GHz) sampling voltmeter (WSV) has been developed that greatly improves NIST's ability to perform accurate measurements of various electrical waveform parameters. Three replicas of this instrument have been delivered to...

Simplified approach to calculating global warming potentials developed.(General Developments)(Brief Article)
July 1, 2003... NIST scientists, in collaboration with researchers from the Institute of Energy Problems of Chemical Physics, Russian Academy of Sciences, have developed a simplified method of calculating global warming potentials (GWPs) of halogenated...

Research progresses toward critical molecular electronics measurements.(General Developments)(Brief Article)
July 1, 2003... Research at NIST and a private company is progressing toward reliable methods for measuring the electrical behavior of molecular electronic devices, an emerging nanotechnology eyed for future integrated circuits. Using a crossbar test...

NIST/SEMATECH collaboration leads to breakthrough on interface state density extraction.(General Developments)(Brief Article)
July 1, 2003... A NIST scientist, in collaboration with researchers at International SEMATECH, recently completed a study of the proper use of capacitance-voltage measurements to extract interface state density of high dielectric-constant (alternate) gate...

Optimal vector-network-analyzer calibration algorithm developed by NIST staff.(General Developments)(Brief Article)
July 1, 2003... NIST and PTB staff have completed StatistiCAL[TM], a software algorithm that combines a decade of experience in applying orthogonal distance regression and other iterative techniques to solving vector network analyzer (VNA) calibrations with an...

NIST researchers demonstrate 120-element focal-plane array for concealed weapons detection.(General Developments)(Brief Article)
July 1, 2003... Millimeter wavelength imaging is a natural approach for concealed weapons detection (CWD) because of the transparency of clothing and the spatial resolution achievable in this spectral region. However, large-format arrays of mm-wave detectors,...

Source of decoherence in Josephson qubits indentified by NIST researchers.(General Developments)(Brief Article)
July 1, 2003... Josephson junctions are good candidates for a quantum computer with recent experiments demonstrating reasonably long coherence times, state preparation, manipulation and measurement, and coupling of qubits for even-tual gate operations. Since a...

NIST researchers develop microcalorimeter arrays using surface micromachining.(General Developments)(Brief Article)
July 1, 2003... The single-pixel superconducting transition-edge sensor (TES) x-ray microcalorimeters developed at NIST enable x-ray spectroscopy with energy resolution that is 10 to 100 times better than conventional semiconductor detectors. This high-energy...

NIST researchers measure the single electron spectrum of InAs quantum dots.(General Developments)(Brief Article)
July 1, 2003... Quantum dots (QD)--nanometer-scale semiconductor islands--are being investigated for a variety of optoelectronic applications, including use as single photon-on-demand sources. Such a source operates by tunneling a single electron and hole onto...

NIST researchers develop new microwave characterization tools for thin film circuits.(General Developments)
July 1, 2003... As the speed of modern electronics increases, thin film dielectric materials are becoming increasingly important circuit elements for integrated electronics, communications, and computing applications. It is important to characterize thin-film...

Phase sensitive neutron reflectometry describes the structure of a membrane-mimetic biomaterial.(General Developments)
July 1, 2003... Scientists at the NIST Center for Neutron Research (NCNR) and the Department of Surgery at Emory University in Atlanta, GA, are using phase-sensitive neutron reflectometry to characterize the structure of a medically relevant membrane-mimetic...

Publication available on Korea's standards and conformity assessment system.(General Developments)
July 1, 2003... A NIST guest researcher from the Korean Agency for Technology and Standards (KATS), prepared a comprehensive report on "Standardization and Conformity Assessment in the Republic of Korea" (NISTIR 6960). The publication describes the national...

Measurements completed for 20 RM 8240 standard bullets.(General Developments)
July 1, 2003... Scratches on a bullet recovered at a crime scene can be as incriminating as fingerprints. Unfortunately, methods for analyzing these tell-tale forensic "signatures" still entail manual comparisons, making firearms-ballistics databases...

AFM probe developed for [M.sup.3].(General Developments)(Brief Article)
July 1, 2003... A new type of probe has been developed for the molecular measuring machine ([M.sup.3]) that allows the imaging of non-conductive samples. [M.sup.3], a one-of-a-kind instrument designed to measure to nanometer accuracy the positions of features...

NIST security specialists publish role-based access control book.(General Developments)
July 1, 2003... NIST scientists recently published a new book, entitled Role-Based Access Control. Designed for software developers, security administrators, and students, the book covers all aspects of role-based access control (RBAC), an advanced access...

NIST collaborates on study of adaptive characterization of jitter noise in sampled high-speed signals.(General Developments)(Brief Article)
July 1, 2003... Researchers at NIST have developed an adaptive functional data analysis method to characterize random timing errors in high-speed sampled signals measured by sampling oscilloscopes. On average, jitter noise blurs a measured signal and reduces...

NIST studies extending the scope of electron-beam tomography.(General Developments)(Brief Article)
July 1, 2003... Tomography is the science of reconstructing three-dimensional structures from a set of two-dimensional images--for example, a set of absorption photographs of the same object taken from different angles, using penetrating radiation such as...

Single atoms delivered on demand.(General Developments)(Brief Article)
July 1, 2003... Scientists at NIST have demonstrated a novel source of atom flux that can provide one, and only one, atom essentially whenever it is needed--the first time such control over neutral atom delivery has been achieved. Reporting in the May 5, 2003...

Scientists study whirlpools in fermion superfluids.(General Developments)
July 1, 2003... The structure of vortices and vortex rings in Bose-Einstein condensates (BECs) has been a subject of intense interest during the past few years and has been studied experimentally at JILA and theoretically in Gaithersburg. Vortices in BECs are...

Data available on atomic spectral tables for the Chandra X-Ray Observatory.(General Developments)(Brief Article)
July 1, 2003... Spectral tables for four cosmically abundant elements (Ne, Mg, Si, and S) in the wavelength region of interest for the Chandra X-Ray Observatory, which is roughly 2 nm to 17 nm, have been critically compiled with partial support from the...

Handbook of basic atomic spectroscopic data available online.(General Developments)
July 1, 2003... NIST has made a handbook of basic atomic spectroscopic information available at physics.nist.gov/ Handbook. The handbook is designed to provide a selection of the most important and frequently used atomic spectroscopic data in an easily...

NIST releases natural ventilation design and analysis tool.(General Developments)(Brief Article)
July 1, 2003... NIST has developed a software tool to assist designers of natural ventilation systems in buildings. The tool, Loop Design and Analysis (LoopDA), is integrated with NIST's existing multizone airflow analysis program, CONTAMW. Prior to this...

First principles calculations of Pb and O vacancies in perovskite compounds performed.(General Developments)
July 1, 2003... Theorists at NIST have performed first principles calculations that have demonstrated that Pb-O vacancy pairs can be a significant source of "random" electric fields in Pb-based perovskite compounds, materials under development for...

NIST hosts workshop on language recognition.(General Developments)
July 1, 2003... NIST hosted the 2003 NIST Language Recognition Workshop at NIST in April 2003. Held in cooperation with Department of Defense (DoD) sponsors, the workshop reviewed the recent evaluation of language recognition research systems in this area. Six...

NCNR'S user-friendly rietveld software has wide impact on structure analysis.(General Developments)
July 1, 2003... Rietveld refinement allows crystallographic analyses to be performed by profile fitting of powder diffraction data. It is widely applied in chemistry, geology, materials science, condensed-matter physics, engineering, and most recently in the...

Phase equilibria data for electronic ceramics published.(General Developments)
July 1, 2003... The first volume of a collection of phase diagrams focused on the increasingly important field of electronic ceramics was presented to the American Ceramic Society (ACerS) at its annual meeting in April 2003. The new volume details the phase...

NIST writes first MEMS standards.(General Developments)
July 1, 2003... The first microelectromechanical systems (MEMS) standards in the world will be published in the Annual Book of ASTM Standards this summer. The three-standard test methods are for measuring in-plane lengths, residual strain, and strain gradient....

Researchers use new method for in situ tip regeneration in vacuum.(General Developments)(Brief Article)
July 1, 2003... Using the NIST-developed molecular measuring machine ([M.sup.3]), NIST researchers have implemented a method for in situ tip regeneration without having to break vacuum to change the tip. By scanning a blunt tip at 0.1 [micro]m/s over the tops...

Sensitive microsensors recognize chemical warfare agents.(General Developments)
July 1, 2003... Researchers at NIST have developed microsensors that detect nmol/mol quantities of chemical warfare agents (CWAs), including sarin (GB), tabun (GA) and sulfur mustard (HD). The recent results represent a significant step forward in the...

NIST develops high-resolution technique for characterization of nanoscale patterns with Small Angle X-Ray Scattering.(General Developments)
July 1, 2003... NIST has demonstrated the application of Small Angle X-ray Scattering (SAXS) as a new measurement method for the non-destructive characterization of nanoscale pattern size and shape at length scales needed for future technology nodes in the...

Overview of the U.S. approach to standards, conformity assessment, and metrology available.(Brief Article)
July 1, 2003... NIST provides assistance to U.S. government agencies and industry in order to overcome or eliminate technical barriers to trade. Since these barriers are often due to differences in standards and conformity assessment practices between the...

NIST develops a Standard Reference Material for peanut butter.(Standard Reference Materials)
July 1, 2003... The Nutrition Labeling and Education Act of 1990 requires that information for selected nutrients be provided on labels for processed foods. In response, NIST has been working to provide food-matrix Standard Reference Materials (SRMs) with...

NIST plays role in keeping tin cans lead-free.(Standard Reference Materials)
July 1, 2003... When steel mills manufacture tin-plated sheet steel for food cans, they must test the tin (Sn) and the electroplating bath for lead (Pb) content. If lead is allowed to accumulate in the tin or the bath, it will become part of the tin coating...