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Jessen, Poul. S. (Optical Sciences/U AZ) Anderlini, M. . (Guest/842) ( ). Sebby-Strabley, Jennifer. Porto, J. (ATOMIC PHYSICS DIVISION 842).
A Lattic of Double-Wells for Manipulating Pairs of Cold Atoms
To be submitted for publication in: To Be Determined

We describe the design and implementation of a 2D optical lattice of double wells suitable forisolating and manipulating an array of individual pairs of atoms in an optical lattice. Atoms inthe square lattice can be placed in a double well with any of their four nearest neighbors. Theproperties of the double well (the barrier height and relative energy offset of the paired sites) canbe dynamically controlled. The topology of the lattice is phase stable against phase noise impartedby vibrational noise on mirrors. We demonstrate the dynamic control of the lattice by showing thecoherent splitting of atoms from single wells into double wells and observing the resulting double-slitatom diffraction pattern. This lattice can be used to test controlled neutral atom motion amonglattice sites and should allow for testing controlled two-qubit gates.
Keywords: cold atoms , optical lattices , quantum computation , quantum information
Approved: January 25, 2006.

Jackson, C. M. Wielgosz, R. I. ( ). May, W. E. (CHEMICAL SCIENCE AND TECHNOLOGY LABORATORY OFFICE 830).
A New Opportunity to Participate in an International Effort for Achieving Comparability of Test Results Used in Laboratory Medicine
To be submitted for publication in: In Vitro Diagnostics Technology

Globalization in the in vitro diagnostics (IVD) industry is occurring in the same way as it is being experienced in other industries. However, one extremely important difference distinguishes health related industries from consumer product producers; medical products are subject to regulatory requirements almost unimaginable in other industries. Professionals from laboratory medicine, the IVD industry and chemical metrology organizations have come together to address the challenges of globalization in the production of medical products, laboratory needs for quality and uniformity of the results of laboratory tests, and regulatory requirements and the demands of regulators throughout the world. The Joint Committee for Traceability in Laboratory Medicine, JCTLM has been formed to aid laboratory medicine, patients and physicians by providing services to IVD manufacturers and regulators of IVDs. Descriptions of the JCTLM and its activities have been presented in IVD Technology.
Keywords: Certified Reference Materials , comparability , in vitro , JCTLM , laboratory medicine , Reference Measurement Procedures
Approved: January 25, 2006.

Kucklick, J. R. Dodder, N. G. Peck, Aaron. Sander, L. C. (ANALYTICAL CHEMISTRY DIVISION 839).
Analysis of Hexabromocyclododecane Diastereomers and Enantiomers by Liquid Chromatography Tandem Mass Spectrometry: Chromatographic Selectivity and Ionization Matrix Effects
To be submitted for publication in: Journal of Analytical Chemistry

Hexabromocyclododecane (HBCD) is a flame retardant that is undergoing environmental risk assessment. The liquid chromatographic retention and electrospray ionization matrix effects were investigated for HBCD methods of analysis for environmental matrices. Column selectivity towards HBCD diastereomers was evaluated for C30 and C18 stationary phases under different mobile phase conditions and column temperatures. The HBCD elution order was dependent on the shape selectivity of the stationary phase and the mobile phase composition. Greater resolution of B-HBCD and y-HBCD was achieved with the use of an acetonitrile / water (compared with a methanol / water) mobile phase composition. A liquid chromatography / electrospray ionization tandem mass spectrometry (LC / ESI-MS/MS) method for the analysis of HBCD in biological tissues was evaluated for potential matrix effects. The influence of extracted matrix components on HBCD diastereomer and enantiomer analysis was investigated using a postextraction addition approach. Although the analysis of HBCD diastereomers was relatively unaffected by the sample matrix, HBCD enantiomers in tissue samples were significantly influenced by extracted matrix components. The use of racemic 13C-labeled HBCD diastereomers as internal standards for enantiomer fraction measurements corrected for the changes in the mass spectrometer response.
Keywords: electrospray ionization , enantiomer fraction , hexabromocyclododecane , liquid chromatography , matrix effects , shape selectivity , stable isotope internal standard , tandem mass spectrometry
Approved: January 25, 2006.

Foecke, Tim. . Banovic, S. W. Gayle, F. W. (METALLURGY DIVISION 855).
Assessment of Structural Steel From the World Trade Center Towers. Part I: Recovery and Identification of Critical Structural Elements
To be submitted for publication in: Journal of Failure Analysis and Prevention

In response to the events of September 11, 2001, the National Institute of Standards and Technology (NIST) conducted a 3 year, $16 M investigation of the World Trade Center (WTC) disaster. A primary goal of the WTC investigation was to explore the building materials and construction and the technical conditions that contributed to the outcome of the tragedy. This series of papers describes facets of the investigation involving the recovery and identification efforts of the structural components and the evaluation of the steel with regard to damage and degradation as a result of the events of the day. The present paper covers unique aspects concerning the recovery of the structural elements and their subsequent identification with respect to their original as-built locations within the towers. A total of 236 pieces of WTC steel were cataloged, including several exterior and core columns from the impact and fire floors of WTC 1 and WTC 2.
Keywords: identification , recovery , structural steel , World Trade Center Towers
Approved: January 25, 2006.

Ahrens, M. T. (UNC Charlotte) Stokes, E. B. (UNC Charlotte) Motayed, A. (UMD) Harris, T. R. (UNC Charlotte) Morton, S. T. (General Dynamics) ( ). Schenck, P. K. (CERAMICS DIVISION 852). Davydov, A. V. (METALLURGY DIVISION 855).
Combinatorial Study of Nickel-Gold P-Contacts for Blue Indium Gallium Nitride Light-Emitting Diodes
To be submitted for publication in: Electrochemical Society

Although the efficiency of the Gallium Nitride (GaN) Light Emitting-Diode (LED) has improved in the past decade, a great opportunity for further efficiency improvement lies in the optimization of the Nickel-Gold composition of the p-type GaN metal contacts. The work described here will analyze the properties and performance of LED p-type contacts with varying Nickel-Gold (Ni-Au) compositions. In this work, during the electron-beam deposition of the Ni and Au onto an LED wafer, the relative thicknesses of the two metals were spatially varied to provide a combinatorial array of Ni an Au compositions on a single LED wafer. Each Ni-Au composition on the LED wafer was then analyzed for optical transmittance before and after annealing. LED devices were finally fabricated from the wafer, and the resultant overall power efficiencies of the fabricated LED devices were evaluated as a function of Ni and Au thickness.
Keywords: combinatorial study , gallium nitride , indium nitride , light emitting diode , nickel-gold contacts
Approved: January 25, 2006.

Fong, Terrance. (NASA/Ames) Schultz, Alan. (NRL) Steinfeld, Aaron. (Cranegie-Mellon U) Kaber, David. (NC State U) Lewis, Michael. (U/Pittsburgh) Goodrich, Michael. (Brigham Young U) ( ). Scholtz, J. C. (INFORMATION ACCESS DIVISION 894).
Common Metrics for Human-Robot Interaction
To be submitted for publication in: Human Robot Interaction (HRI)

This paper describes an effort to identify common metrics for task-oriented human-robot interaction (HRI). We begin by discussing the need for a toolkit of HRI metrics. We then describe the framework of our work and identify important biasing factors that must be taken into consideration. Finally, we present a case study. Preparation of a larger, more detailed toolkit is in progress.
Keywords: Human-robot interaction , metrics , unmanned ground vehicles
Approved: January 25, 2006.

Brock, Joel. D. (Cornell Univ) ( ). Pomeroy, J. M. (ATOMIC PHYSICS DIVISION 842).
Critical Nucleus Phase Diagram for the Cu(100) Surface
To be submitted for publication in: Physical Review B

An experimental exploration of island nucleation dynamics during epitaxial film growth on the Cu(100) surface is presented that connects previous results from other groups at low temperatures with the room temperature regime. The steady-state balance of various atomistic processes during the island nucleation process has direct impact on the physical properties of epitaxial films, e.g. greater nucleation densities allow layer-by-layer growth to be achieved at lower temperatures. Within many theoretical frameworks, the critical nuclei size i (the largest assembly of atoms with a higher probability for decay than growth) plays a major role in determining island nuclei densities, and, by extension, the physics of film growth. This paper presents island density and distribution results from recent STM studies and analysis that allows for accurate determination of the critical nuclei size at various deposition rates and temperatures near room temperature and the i=1 to i=3 boundary (dimer to tetramer). This is accomplished by using the scaling behavior of coarsening to develop statistical weight by rescaling individual distributions and summing them. The results of this study are then combined with previously published results from other researchers to empirically determine the structure of the phase boundary from i=1 to i=3 as a function of temperature and deposition rate. At low temperatures and fluxes, the position of the phase boundary agress with expected position when only adatom mobility is considered. Deviations at higher temperatures suggest that the mobility of dimers and other small islands may be important in determining the effective critical nucleus near room temperature.
Keywords: nucleation dynamics , homoepitaxy , mean-field , scanning tunneling microscope , coarsening , critical island size , diffusion , thin films
Approved: January 25, 2006.

Walton, A. J. (UK) Shulver, B.J.R.. (U/Edinburg/UK) Bunting, A. S. (U/Edinburgh/UK) Gundlach, A. (U/Edinburgh/UK) Haworth, L. I. (U/Edinburgh/UK) Ross, A.W.S.. (U/Edinburgh/UK) Snell, A. J. (U/Edinburgh/UK) Stevenson, J.T.M.. (U/Edinburgh/UK) ( ). Cresswell, M. W. Allen, R. A. (SEMICONDUCTOR ELECTRONICS DIVISION 812).
Design and Fabrication of a Copper Test Structure for Use as an Electrical Critical Dimension Reference
To be submitted for publication in: IEEE International Conference on Microelectronic Test Structures

Keywords: Chemical Mechanical Polishing (CMP) , copper , Critical Dimension (CD) , interconnect , reference material
Approved: January 25, 2006.

Douglas, J. F. VanderHart, D. L. Anopchenko, O. Psurek, Tatiana. Obrzut, J. (POLYMERS DIVISION 854).
Dielectric Study of the Anti-Plasticization of Trehalose by Glycerol
To be submitted for publication in: Physics Review E

Recent measurements have suggested that the antiplasticizing effect of glycerol on trehalose can significantly increase the preservation times of proteins stored in this type of preservative formulation. In order to better understand the physical origin of this phenomenon, we examine the nature of antiplasticization in trehalose-glycerol mixtures by dielectric spectroscopy. These measurements cover a broad frequency range between 40 Hz to 18 GHz (covering the secondary relaxation range of the fragile glass-former trehalose and the primary relaxation range of the strong glass-former glycerol) and a temperature (T) range bracketing room temperature (220 K to 350 K). The Havrilak-Negami function precisely fits our relaxation data and allows us to determine the temperature and composition dependence of the relaxation time t describing a relative fast dielectric relaxation process appropriate to the characterization of antiplasticization. We observe that increasing the glycerol concentration at fixed T increases t (i.e., antiplasticization) until a T dependent critical ‘plasticization concentration’ xwp is reached where it then decreases precipitouslyAt a fixed concentration, we find a temperature at which antiplasticization first occurs upon cooling and we designate this as the ‘antiplasticization temperature’, Tant. The ratio of the t values for the mixture and pure trehalose is found to provide a useful measure of the extent of antiplasticization and we explore other potential measures of antiplasticization relating to the dielectric strength.
Keywords: bio-preservation , dielectric relaxation , glassy dynamics , trehalose
Approved: January 20, 2006.

Halleck, P. M. (PA S Univ) Grader, A. S. (PA S Univ) ( ). Bentz, D. P. (MATERIALS AND CONSTRUCTION RESEARCH DIVISION 861). Roberts, J. W. (CONVERGENT INFORMATION SYSTEMS DIVISION 894).
Direct Observation of Water Movement During Internal Curing Using X-Ray Microtomography
To be submitted for publication in: Concrete International

The goal of internal curing of concrete, via the utilization of saturated lightweight fine aggregates (LWA) for example, is to provide internal reservoirs of water that are readily available to supply the hydrating cement paste with the water needed to maintain saturation within its capillary porosity throughout the first days or weeks of hydration. It has been suggested that this water availability is especially critical during the first day of hydration in high-performance concretes, as without it, significant autogenous shrinkage and possibly cracking can occur. In this paper, water movement during the internal curing of a high-performance mortar containing saturated LWA is directly observed using three-dimensional x-ray microtomography with a voxel dimension of about 20 micrometers (8x10-4 in.). With this technique, the emptying of individual “pores” within the LWA can be readily observed. For the mixture proportions employed in this study, much of the LWA reservoir water was removed within the first 24 h of hydration at 30 oC (86 oF). The observations of water movement are supported by more conventional measures of performance including degree of hydration based on loss-on-ignition measurements and compressive strength of mortar cubes.
Keywords: building technology , hydration , internal curing , lightweight aggreates , x-ray microtomography
Approved: January 25, 2006.

Gentile, C. . (ADVANCED NETWORK TECHNOLOGIES DIVISION 892).
Distributed Sensor Location Through Linear Programming With Triangle Inequality Constraints
To be submitted for publication in: To Be Determined

Interest in dense sensor networks due to falling prices and reduced size has motivated research in sensor location in recent years. To our knowledge, the algorithm which achieves the best performance in sensor location solves an optimization program by relaxing the quadratic geometrical constraints of the network to render the program convex. In recent work we proposed solving the same program, however by applying convex geometrical constraints directly, necessitating no relaxation of the constraints and in turn ensuring a tighter solution. This paper proposes a distributed version of our algorithm which achieves the same globally optimal objective function as the decentralized version. We conduct extensive experimentation to substantiate the robustness of our algorithm even in the presence of high levels of noise, and report the messaging overhead for convergence.
Keywords: simplex method , primal-dual method , quadratic programming , semi-definite programming
Approved: January 25, 2006.

McMichael, R. D. Maranville, B. B. (METALLURGY DIVISION 855).
Edge Saturation Fields and Dynamic Edge Modes in Ideal and Non-Ideal Magnetic Film Edges
To be submitted for publication in: Physical Review B

This paper describes modeling of the micromagnetic behavior near edges of ferromagentic thin films when uniform fields are applied in plane and perpendicular to the edge.
Keywords: dynamics edge modes , magnetic film edge , ferromagnetic thin films
Approved: January 25, 2006.

Han, Charles. C. (Chinese Acad./Science) Yao, Yonghua. (Chinese Acad./Science) Zhang, Ruoyu. (Chinese Acad./Science) ( ). Hobbie, E. K. (POLYMERS DIVISION 854).
Effect of Shear Flow on Multi-Component Polymer Mixtures
To be submitted for publication in: Polymer

There is considerable interest in the phase behavior of multi-component polymer mixtures, the so-called polymer blends, due to their broad technological importance in the plastics industry. Traditionally, quiescent conditions have been adopted for characterizing the phase behavior of polymer blends, with the majority of past work emphasizing two different but related aspects. In contrast, the response of polymer blends and solutions to shear flow, a key factor in polymer processing, has only very recently been studied in a systematic manner. We present an experimental review of the shear-induced phase behavior of polymer blends and solutions. Special attention is given to the flow-structure relationship near a critical point of unmixing.
Keywords: polymer blends , shear flow , mixing , demixing
Approved: January 25, 2006.

Govorov, A. O. (Ohio U) Zhang, Wei. (Ohio U) Skieni, T. (Ohio U) Lee, J. (U/MI) Kotov, N. A. (U/MI) Slocik, Joseph. M. (WPAFB) Naik, Rajesh. R. (WPAFB) ( ). Bryant, G. W. (ATOMIC PHYSICS DIVISION 842).
Exciton-Plasmon Interaction and Hybrid Excitons in Semiconductor-Metal Nanoparticle Assemblies
To be submitted for publication in: Nanoletters

We describe physical properties of excitons in hybrid complexes composed of semiconductor and metal nanoparticles. The interaction between individual nanoparticles is revealed as an enhancement or suppression of emission. Enhanced emission comes from electric field amplified by the plasmon resonance whereas emission suppression is a result of energy transfer from semiconductor to metal nanoparticles. The emission intensity and energy transfer rate strongly depend on the geometrical parameters of the superstructure and the physical and material properties of the nanoparticles. In particular, the emission enhancement effect appears for nanoparticles with relatively small quantum yield and silver nanoparticles have stronger enhancement compared to gold ones. Using realistic models, we review and analyze available experimental data on energy transfer between nanoparticles. In hybrid superstructures conjugated with polymer linkers, optical emission is sensitive to environmental parameters such as, for example, temperature. This sensitivity comes from expansion or contraction of a linker. With increasing temperature, emission of polymer-conjugated complexes can decrease or increase depending on the organization of a superstructure. The structures described here have potential as sensors and actuators.
Keywords: bioconjugates , energy transfer , excitons , nanooptics , nanoparticles , plasmons , quantum dots
Approved: January 25, 2006.

Lawn, B. R. Chai, H. (MATERIALS SCIENCE AND ENGINEERING LABORATORY OFFICE 850).
Failure of Glass Layers on Polymeric Substrates From Vickers Indentation
To be submitted for publication in: Scripta Materialia

A study is made of median crack evolution in brittle coatings subjected to sharp contacts. A model bilayer system consisting of a glass plate bonded to a polycarbonate base, with a Vickers pyramid as indenter, is used to demonstrate the evolution in situ. Newly initiated median cracks have the geometry of subsurface pennies containing the indentation axis and an indenter diagonal. The median cracks undergo a phase of stable downward growth with increasing load. Beyond the coating mid-plane, flexural stresses (coupled with the local contact field) elongate and accelerate the median cracks downward through the lower half of the brittle plate, causing unstable failure. Critical loads corresponding to this failure state diminish with decreasing layer thickness until, at small thicknesses (˜ 300 µm in our bilayer system), failure occurs spontaneously at initiation, i.e. without any stable growth phase. The highly deleterious nature of the median failure mode in a broad spectrum of brittle coatings and films is emphasized.
Keywords: bilayers , brittle coatings , glass , median cracks , Vickers indentation
Approved: January 25, 2006.

Kim, J. (POSTECH U/Korea) Lee, J. (Korea Advance Tech.&Std.) Snack, P. (AIAG) Cho, H. . (POSTECH University-Korea) ( ). Woo, J. Kulvatunyou, B. . (Pennsylvania State Univer) Ivezic, N. . (Oak Ridge National Labora) (MANUFACTURING SYSTEMS INTEGRATION DIVISION 826).
Information Mapping Conformance Test Tools
To be submitted for publication in: International Conference on Software Enterprise and Application

As data exchange standards can hardly be created without ambiguity and potential for differing interpretations, conformance and interoperability tes-ting capabilities are increasingly important to enable and maintain interopera-bility between e-business partners. Typically, testing of e-business system fol-lows e-business systems architectures that identify key modular stacks such as communication protocol stack, interaction/business protocol stack, and mes-sage/content protocol stack. This paper describes test development and execu-tion tools and procedures for a class of conformance tests in the mes-sage/content protocol stack corresponding to a data exchange specification called information mapping test. The tools are designed to increase automation of the testing processes and significantly decrease costs of test cases develop-ment and execution. These tools are under development to support self-testing capability in a B2B interoperability project within the auto industry. The in-formation mapping conformance test seeks to ensure that the semantics of the message elements are implemented and interpreted according to the intended meaning. A testing execution tool has been developed as an extension to the ebXML Interoperability, Implementation, and Conformance (IIC) test frame-work specification, originally defined to test the communication protocol stack. This extension not only maintains the original testing architecture but also al-lows the information mapping test to be modular to the communication proto-col (i.e., the information mapping test can be performed using any communica-tion protocol).
Keywords: mapping test , data exchange integration , Business Object Document , conformance testing , interoperability testing , content-level test
Approved: January 25, 2006.

Van Workum, Kevin. (Naval Academy) ( ). Douglas, J. F. (POLYMERS DIVISION 854).
Lessons From Simulation Regarding the Control of Synthetic Self-Assembly
To be submitted for publication in: Materials Research Society

We investigate the role of the particle potential symmetry on the form of self-assembly by Monte Carlo simulation with the particular view towards synthetically creating structures of prescribed form and function. We establish a general tendency for the potential rotational symmetries to be locally preserved in the self-assembled structure. We also show that the introduction of seeds provides an effective method for controlling the structure of the sheet-like polymers and their growth kinetics. The physical significance of these distinct modes of polymerization is illustrated by constructing an artificial centrosome structure derived from particles having continuous and discrete rotational symmetries.
Keywords: polymer melt , glass transition , antiplasticer additives , nanoparticles , fragility , shear modulus , film imprinting , biomaterial preservation
Approved: January 25, 2006.

Ford, Chris. (U/Western Australia) Malament, Kenneth. (Tufts U) Hu, X. Z. (Australia) Bush, M. (Australia) Qasim, T. . (U/Western Australia) ( ). Lawn, B. R. (MATERIALS SCIENCE AND ENGINEERING LABORATORY OFFICE 850).
Margin Failures in Brittle Dome Structures: Relevance to Failure of Dental Crowns
To be submitted for publication in: Journal of Biomedical Materials Research

Margin cracks in loaded brittle dome structures are investigated. Dome structures consisting of glass shells filled with polymer resin, simulating the essential features of brittle crowns on tooth dentin, provide model test specimens. Disk indenters of diminishing elastic modulus are used to apply axisymmetric loading to the apex of the domes. Previous studies using hard indenters have focused on fractures initiating in the near-contact region of such specimens, including radial cracks at the glass undersurface directly below the contact axis. Here we focus on fractures initiating at the remote support margins. Margin cracks can become dominant when loading forces are distributed over broad contact areas, as in biting on soft matter, here simulated by balsa wood disks. Cracks preinitiated at the dome edges during the specimen preparation propagate under load around the dome side into segmented, semi-lunar configurations reminiscent of some all-ceramic crown failures. Finite element analysis is used to determine the basic stress states within the dome structures, and to confirm a shift in maximum tensile stress from the near-contact area to the dome sides with more compliant indenters.
Keywords: all-ceramic crowns , crown failure , lunar cracks , stress analysis
Approved: January 25, 2006.

Francis, M. H. Wilson, P. . Guerrieri, J. J. (ELECTROMAGENETICS DIVISION 818). Stroup, D. W. Bryner, N. P. (FIRE RESEARCH DIVISION 866). Miller, L. E. Klein-Berndt, Luke. (ADVANCED NETWORK TECHNOLOGIES DIVISION 892).
RFID-Assisted Indoor Localization and Communication for First Responders
To be submitted for publication in: Advanced Radio Technologies

An indoor localization and communication project is described that proposes to use RFID tags, placed in the building beforehand, as navigation waypoints for an inertial navigation system carried by a first responder. The findings from the first year of the planned three-year project are summarized.
Keywords: RFID , homeland security , indoor localization , wireless communication , public safety , dead reckoning
Approved: January 25, 2006.

Sales, B. . (ORNL) Mandrus, D. . (ORNL) Jin, R. . (Oak Ridge NL) Lumsden, M. D. (ORNL) Stone, M. B. (ORNL) Nagler, S. E. (ORNL) ( ). Qiu, Yiming. . (NIST CENTER FOR NEUTRON RESEARCH 856).
Temperature Dependent Bilayer Ferromagnetism in Sr3Ru^d2^O^d7^
To be submitted for publication in: Physical Review B

The Ruthenium based perovskites exhibit a wide variety of interesting collective phenomena related to magnetism originating from the Ru 4d electrons. Much remains unknown concerning the nature of magnetic fluctuations and excitations in these systems. We present results of detailed inelastic neutron scattering measurements of Sr3Ru2O7 as a function of temperature, probing the ferromagnetic fluctuations of the bilayer structure. A magnetic response is clearly visible for a range of temperatures, T = 3.8 K up to T = 100 K, and for energy transfers between ??? = 2 and 14 meV. These measurements indicate that the ferromagnetic fluctuations manifest in the bilayer structure factor persist to surprisingly large temperatures. This behavior may be related to the proximity of the system in zero magnetic field to the metamagnetic/ferromagnetic transition.
Keywords: Sr3Ru^d2^O^d7^ , bilayer ferromagnetism
Approved: January 25, 2006.

Radack, S. M. (COMPUTER SECURITY DIVISION 893).
Testing and Validation of Personal Identity Verification (PIV) Components and Subsystems for Conformance to Federal Information Processing Standard 201
To be submitted for publication in: ITL Bulletin

This bulletin provides information about testing and validation of personal identity verification (PIV) components and subsystems for conformance to Federal Information Processing Standard 201, Personal Identification Verification of Federal Employees and Contractors. The bulletin discusses requirements for federal organizations to issue identification cards to their employees and contractors who require access to federal facilities and information systems, and the NIST technical publications that specify the administrative procedures and technical specifications for incorporating an individual’s identity credentials on smart cards. The bulletin advises agencies and vendors about the requirements for testing and validation of the Personal Identification Verification (PIV) components and subsystems that use the electronically stored data on the cards to carry out automated identity verification of the individual. References and sources of information on personal identification and on conformance testing are provided.
Keywords: accreditation , biometric data , certification , cryptographY , FIPS , Homeland Security , identification standard , Personal Identification Verification , PIV
Approved: January 25, 2006.

Poskrebychev, G. (Oak Crest Inst/CA) Kurylo, M. (NASA/WDC) ( ). Orkin, V. L. Kozlov, S. N. (Russian Academy of Scienc) (PHYSICAL AND CHEMICAL PROPERTIES DIVISION 838).
The Rate Constant for the Reaction of OH With H^d2^ Between 200 K and 480 K
To be submitted for publication in: International Conference on Characterization and Metrology for ULSI Technology

The rate constant for the reaction of OH radicals with molecular hydrogen was measured using the flash photolysis resonance-fluorescence technique over the temperature range 200 K to 479 K. The Arrhenius plot was found to exhibit a noticeable curvature. Careful examination of all possible systematic uncertainties indicates that this curvature is not due to experimental artifacts. The rate constant can be represented by the following expressions over the indicated temperature intervals: cm3 molecule-1 s-1 above T = 250 K and cm3 molecule-1 s-1 below T = 250 K. No single Arrhenius expression can adequately represent the rate constant over the entire temperature range within the experimental uncertainties of the measurements. The overall uncertainty factor was estimated to be These measurements indicate an underestimation of the rate constant at lower atmospheric temperatures by the present recommendations. The global atmospheric lifetime of H2 due to its reaction with OH was estimated to be 10 years.
Keywords: hydroxyl radical , hydrogen , H2 , atmospheric lifetime
Approved: January 25, 2006.