NIST Technicalendar January 12 to January 16, 2009 The NIST Technicalendar is issued each Friday. All items MUST be submitted electronically from this web page by 12:00 NOON each Wednesday unless otherwise stated in the NIST Technicalendar. The address for online weekly editions of the NIST Technicalendar and NIST Administrative Calendar is: http://www.nist.gov/tcal/.

In this Issue: Meetings at NIST Meetings Elsewhere Announcements Talks by NIST Personnel NIST Web Site Announcements NIST Administrative Calendar (current)   NIST Vacancy Announcements (current)

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No Scheduled Events

10:30 AM - Spins in Quantum Dot Molecules
10:30 AM - Present and Future Plans for Biomass Research at DOE
2:30 PM - What's New at TIP?

10:30 AM - Relationship Between Structure and Dynamics of Complex Fluids
10:30 AM - Building the Bio-Device Interface: Electro-Addressing with Stimuli-Responsive Polysaccharides
11:00 AM - Measurement Performance Issues in Microarray Gene Expression Images and Spike-in Experiments

10:30 AM - Correlation of Microstructure and Magnetotransport in Organic Semiconductor Spin Valve Structures
10:30 AM - "Green Ideas" at the National Science Foundation (NSF)
10:45 AM - Investigation of Hydrogen Adsorption in Different Nanoporous Materials over Wide Ranges of Pressure and Temperature

No Scheduled Events

1/12 -- MONDAY

No Scheduled Events

1/13 -- TUESDAY

10:30 AM - ATOMIC PHYSICS DIVISION SEMINAR: Spins in Quantum Dot Molecules
Quantum dots are often described as artificial atoms because the three dimensional confinement leads to discrete energy states analogous to atomic energy levels. In recent years there has been a flurry of research on quantum dots motivated largely by proposals to use spins confined in quantum dots for quantum information processing. One of the major challenges for these quantum information schemes is the mechanism for controllably coupling separate quantum dots. In order to study the physical interactions that could be used to control coupling between separate dots, we have used MBE growth techniques to create coupled pairs of quantum dots. We call these coupled pairs of dots "quantum dot molecules" because they exhibit molecular wavefunctions. In this talk, I will describe the growth of quantum dot molecules and present the characteristic photoluminescence patterns that allow us to understand the coupling mechanisms. We find that the combination of spin exchange interactions and tunneling lead to complex photoluminescence spectra that can be understood with relatively simple models of the molecular states. We also find that there are uniquely molecular spin properties. For example, the formation of delocalized molecular states for a single hole leads to a very large resonant enhancement or reduction of g-factor that can be controlled with an applied electric field. Using this effect to identify the symmetry of the wavefunction, we have now found that the energetic order of the bonding and anti-bonding molecular states goes through a reversal as a function of tunnel barrier thickness. This non-intuitive effect arises from the spin-orbit interaction.
Matt Doty , Department of Materials Science and Engineering, University of Delaware.
Physics Building, Room B145. (NIST Contact: Neil Zimmerman, 301-975-5887, neil.zimmerman@nist.gov)

10:30 AM - CHEMICAL SCIENCE AND TECHNOLOGY LABORATORY OFFICE SEMINAR: Present and Future Plans for Biomass Research at DOE
Joyce Yang , AAAS Science Fellow, Office of the Biomass Program, DOE, Washington, DC.
227 Bldg, Rm. A302. (NIST Contact: Wing Tsang, 301-975-2507, wing.tsang@nist.gov)

2:30 PM - DIRECTOR'S OFFICE, ADVANCED TECHNOLOGY PROGRAM SEMINAR: What's New at TIP?
TIP's first competition and results? Plans, expectations, and critical national need topics for 2009? The launching of the exciting new TIP Associates program? These and related topics will be the subject of this informational briefing open to all NIST staff. To accommodate schedules, the event will be repeated on three dates. Please RSVP to Michelle Beddow, x8910, in advance of each event.
Thomas Wiggins , Director, Selection Management Office, TIP. Michael Schen , Senior Scientific Advisor to the Director, TIP.
Administration Bldg, Lecture Rm. B. (NIST Contact: Thomas Wiggins, 301-975-5416, thomas.wiggins@nist.gov)
Special Assistance Available


1/14 -- WEDNESDAY

10:30 AM - PHYSICAL AND CHEMICAL PROPERTIES DIVISION SEMINAR: Relationship Between Structure and Dynamics of Complex Fluids
Dynamical processes of fluids and their mixtures lie at the heart of chemical engineering practice and research, and technological applications increasingly rely on understanding them in the context of systems that show complex behaviors. For example, the mobility of suspended colloidal particles can paradoxically increase if their interparticle attractions increase, while the viscosity of aqueous solutions can anomalously decrease under compression. For simple liquids, dynamics track, at least qualitatively, the degree of interparticle correlations, or structural order, between the fluids constituent particles. Does this fact also hold for more complex fluid systems? In this talk, we investigate via simulation the dynamical properties for a host of complex fluid systems in terms of there underlying structural order. We show that structural order provides a simple unifying framework to understand a diverse range complex behavior.
William Krekelberg, Ph.D , Department of Chemical Engineering/The University of Texas, Austin, TX.
Physics Building, Room A366. (NIST Contact: Vincent Shen, 301-975-2461, vincent.shen@nist.gov)

10:30 AM - BIOCHEMICAL SCIENCE DIVISION SEMINAR: Building the Bio-Device Interface: Electro-Addressing with Stimuli-Responsive Polysaccharides
There is considerable interest in coupling the capabilities of biology for molecular recognition with the capabilities of microelectronics for high speed signal processing and wireless communication. A key limitation is the effective integration of the labile biological components into the device. Our group is examining the potential for biofabricating the bio-device interface using materials and mechanisms from biology. Specifically, we are enlisting stimuli-responsive polysaccharides that can be induced to undergo reversible sol-gel transitions in response to locally-imposed electrical signals. Chitosan is an aminopolysaccharide that is soluble at low pH but undergoes gel formation as the pH approaches its pKa (» 6.3). Chitosan can be electrodeposited at a cathode surface in response to the localized high pH generated by electrochemical reduction reactions. Once electrodeposited, the chitosan film can be electrochemically activated by anodic oxidation. Spectroscopic evidence indicates that anodic oxidation generates carbonyl moieties (presumably aldehydes) that can react with proteins. The combination of electrodeposition and electrochemical conjugation provides a reagentless method to quantitatively assemble proteins at electrode addresses. Alginate is an acidic polysaccharide that can undergo gel formation in the presence of calcium ions. Recent studies demonstrate that alginate can be induced to undergo gel formation at the anode. Experimental results show that E. coli cells can be co-deposited with calcium alginate and the cells are entrapped within the hydrogel network. Further, these cells were able to multiply within the gel and could respond to their environment (i.e., be induced). Finally, the entrapped cells could be released from the alginate network by adding compounds (e.g., sodium citrate) that bind calcium ions. Our results suggest that the electrodeposition of stimuli-responsive, gel-forming polysaccharides could offer important opportunities for microarray and lab-on-a-chip devices.
Gregory Payne , Director of the Center for Biosystems Research, University of Maryland Biotechnology Institute.
ACSL Bldg, Rm. A202. (NIST Contact: Wyatt Vreeland, 301-975-8513, wyatt.vreeland@nist.gov)

11:00 AM - STATISTICAL ENGINEERING DIVISION SEMINAR: Measurement Performance Issues in Microarray Gene Expression Images and Spike-in Experiments
Microarray platforms have been widely used in multiplexed biological measurements. Measurement performance evaluation involves quantitative assessment of several stages of data collection and algorithmic summarization processes, including image analysis, background correction, and statistical modeling. I will review work from NIST Gene Expression Metrology Project in the area of image analysis for microarray gene expression scanner experiments, and multiphase regression statistical modeling for measurement input-output relationships in spike-in microarray experiments. In particular, I will discuss a probabilistic procedure for background correction for data near detection limit and the implications of taking the log-transformation on the data after background correction.
John Lu , Mathematical Statistician.
222 Bldg, Rm. A326. (NIST Contact: John Lu, 301-975-3208, john.lu@nist.gov)


1/15 -- THURSDAY

10:30 AM - CNST ELECTRON PHYSICS GROUP SEMINAR: Correlation of Microstructure and Magnetotransport in Organic Semiconductor Spin Valve Structures
There is currently a rapidly increasing interest in spin-dependent electronic transport in organic semiconductors (OSC). At its heart, this is based on the expectation that weak spin-orbit coupling in these light-element-based materials will lead to long spin relaxation times and long spin coherence lengths that may ultimately enable their use in magnetoelectronic devices. However, while there are several reports of observation of magnetotransport effects in multilayer OSC spin valve structures, the origins are still under debate, and both spin polarized tunneling and spin-coherent diffusive transport mechanisms have been invoked to explain the observed results. We have studied magnetotransport in several Co/OSC/Fe systems, using Alq3, CuPc, PTCDA and CF3-NTCDI as the spin transport layers. Magnetoresistance (MR) was observed up to room temperature in Alq3 and CuPc based devices. Focusing on the Alq3 system, we studied the devices' microstructure by X-ray reflectometry, Auger electron spectroscopy, and polarized neutron reflectometry. Our study shows evidence for spin-coherent diffusive transport and reveals the correlation between microstructure and magnetotransport in these organic devices. In particular, larger MR effects are associated with smaller average roughness at both the Alq3/Co and Fe/Alq3 interfaces. The PNR results show that the chemical and magnetic scattering length depth (SLD) profiles are different at the Alq3/Fe interface. The sample with larger MR has a relatively sharp magnetic interface, indicating there is a better separation between the bulk Fe layer (with bulk-like magnetization) and the interfacial Fe/Alq3 mixed layer (with significantly reduced magnetization). Our studies indicate the importance of detailed control and understanding of interfaces in these systems.
Yaohua Liu , Ph.D. Candidate, Department of Physics and Astronomy, Johns Hopkins University.
Bldg. 217, Rm. H107. (NIST Contact: John Unguris, 301-975-3712, john.unguris@nist.gov)

10:30 AM - ITL SEMINAR: "Green Ideas" at the National Science Foundation (NSF)
Adam D. Silverman is spearheading "Green Ideas" that is taking place in Directorates for both Computer and Information Science and Engineering CISE) and The Mathematical and Physical Sciences (MPS) at NSF. Since it is pretty clear that green ideas are very important to our world and it needs science, we in ITL, and member of other labs of NIST should be interested. Bio: Adam Silverman is currently in the position of Deputy Director for Administrative Services at the National Science Foundation and Chairman of the U.S. Federal Government Small Agency Council Administrative Services Committee. He was previously the Assistant Inspector General for Management and the Director of Program Evaluations at the Department of Treasury. Before moving to the Treasury Headquarters, he served at the former U.S. Customs Service in a series of positions that culminated in a pinnacle job as the Executive Officer to the Commissioner of Customs. He returned to government in 1993 as a Presidential Management Intern after several years as an epidemiology research, education amd consulting programs director for a private consulting firm in Boston, Massachusetts, while attending graduate school at night. Former U.S. Army intelligence officer, emergency medical technician, police dispatcher, and probably the most challenging position ever held, "shopping mall Santa."
Adam Silverman , Deputy Division Director, Administrative Services, NSF, Arlington, VA.
Administration Bldg, Green Auditorium. (NIST Contact: Larry Reeker, 301-975-5147, larry.reeker@nist.gov)

10:45 AM - NIST CENTER FOR NEUTRON RESEARCH SEMINAR: Investigation of Hydrogen Adsorption in Different Nanoporous Materials over Wide Ranges of Pressure and Temperature
Experimental investigations of hydrogen adsorption on different nanoporous materials over wide ranges of pressure and temperature are presented. In a first part, rigorous gravimetric and volumetric methods developed to measure hydrogen adsorption on single-walled carbon nanotubes (SWNTs) are presented. These systems were especially adapted for measurements on small masses and in-situ conditioning. Cross-checked measurements using these methods showed that SWNTs adsorb hydrogen according to mechanisms comparable to other forms of carbons. In a second part, experimental and theoretical methods implemented to study hydrogen adsorption thermodynamics on different metal-organic frameworks (MOFs) are presented. It was found that the best material, MOF-177, can adsorb up to 12.6 wt% at 10 bar and 50 K. This capacity decreases, however, with increasing temperature as a result of weak solid-gas interactions (.H~3-4 kJ/mol). For the lowest measured temperatures, the near-saturation regions of the excess isotherms were used to calculate the adsorbed phase density and volume, two usually eluding quantities. In all tested materials, the adsorbed phase density was found to behave like an incompressible fluid and to reach a density comparable to that of the bulk liquid hydrogen. This conjunction of liquid state properties, exceptional above the critical temperature, could be explained by a traditional micropore filling model. These properties suggest that repulsive interactions and quantum effects could be important limiting factors for the molecular storage of hydrogen under nanoscale confinement.
Eric Poirier , General Motors Corporation, Purdue University. ,.
235 Bldg, Rm. E100. (NIST Contact: Taner Yildirim, 301-975-6228, taner.yildirim@nist.gov)


1/16 -- FRIDAY

No Scheduled Events

ADVANCE NOTICE

1/21/09 11:00 AM - STATISTICAL ENGINEERING DIVISION SEMINAR: Computer Experiments for an Alternative Approach to Mass Measurement
In anticipation of the redefinition of the kilogram and to avoid a parallel non-SI dissemination system for mass, an alternative approach to mass measurement is being developed by constructing a magnetically levitated balance for direct comparison of masses in vacuum versus in air. To build such a balance is extremely challenging due to the requirement of a strong and stable magnetic flux providing rigid link between air and vacuum, a proper electromagnetic shielding to eliminate the stray field, and a minimum uncertainty (highest accuracy) in measurement. Clearly, an optimal design solution can be the key between a success and a failure in achieving these requirements. To aid this process of finding an optimal solution, we have resorted to computer-aided modeling and design. Most electromagnetic computer models are solved using finite element based solvers. The commercially available software package that we use to model the forces on the the magnetically levitated body components and the effect of electromagnetic shielding is a typical example of such an application. One of the features of this software package is the ability to automate the model design process through the use of scripts. This functionality, along with the ability to directly parametrize models, forms the basis for computer experiments. A computer experiment is a number of runs of the computer model (or codes) with various model parameter inputs. In this talk we will describe our computer model including its inputs and response; and we will discuss how we design, implement, and analyze computer experiments to predict the response at untried model parameters and to optimize a functional of the response. Issues concerning the verification and validation of our computer model will also be addressed.
Hung-kung Liu , Statistical Engineering Division, NIST.
Building 222, Rm. A326. (NIST Contact: John Lu, 301-975-3208, john.lu@nist.gov)

1/22/09 10:30 AM - OPTOELECTRONICS DIVISION SEMINAR: Novel Transport Properties of Ga1-xMnxAs and Graphene
Spintronics, a spin-based electronics that takes advantage of electron spin rather than electron charge, has shown remarkable impact in technologies to store and process information. With the discovery and successful commercialization of metal-based spintronics like hard disk, the question has turned to whether it is possible to utilize the spin degree of freedom in semiconductor for superior performance. In response, a key material, Ga1-xMnxAs, has emerged recently and attracted extensive interests because it provides combination of both spin and capabilities of semiconductor, which therefore offers opportunities for a new generation of devices combining microelectronics with spin-dependent effects. As an emergent electronic material and model system for fundamental physics, graphene has become a subject of intense focus, owing to its unusual electronic spectrum and potential applications. In the field of spintronics, graphene is also a rapidly rising star due to its ideal environment for spin-transport, and has been experimentally demonstrated as the first semiconductor spintronics device operated at room temperature. In these two candidate materials for semiconductor spintronics, we have observed many novel transport phenomenon through atomic-scale control of sample growth, nanofabrications, optics measurements, electric transport measurements and a new approach for spintronics research: thermoelectric transport measurements. In this talk, I will introduce: 1. spin-dependent transports in Ga1-xMnxAs, including spin-valve like giant planar Hall effect and planar Nernst effect, anisotropic magneto-thermopower, dissipationless anomalous charge current and heat current; 2. anomalous electric and thermoelectric transports of Dirac particles in single layer graphene, including Quantum Hall effect, diverging behavior in thermopower and anomalously large Nernst signal at the Dirac point under high magnetic field.
Yong Pu , Graduate Student, University of California-Riverside.
Metrology Building, Room B165. (NIST Contact: David Newell, 301-975-4228, david.newell@nist.gov)

1/23/09 10:30 AM - NIST COLLOQUIUM SERIES: Is God a Mathematician?
For centuries, mathematical theories have proven uncannily accurate at describing - and predicting - the physical world. What is it that gives mathematics such powers? In "Is God A Mathematician?" this question will be thoroughly reviewed. The talk will span such fields as mathematics, cosmology, physics, and the cognitive sciences, and will attempt to offer an accessible and lively account of the lives and thoughts of some of the greatest mathematicians and scientists in history, from Archimedes to Galileo and Descartes, and from Newton to Hilbert and Gödel, on up to the present day. Along the way I will discuss another question with which mathematicians, philosophers, and neuroscientists have struggled for centuries: Is mathematics ultimately invented or discovered? Dr. Mario Livio is the acclaimed author of "The Equation That Couldn't Be Solved" and "The Golden Ratio." His new book, "Is God a Mathematician?" will be available for review and purchase before and after the talk. A popular lecturer, he last spoke at NIST in 2004 (Beauty in a Dark Universe).
Mario Livio , Senior Astrophysicist, Space Telescope Science Institute.
Administration Building, Green Auditorium. (NIST Contact: Kum Ham, 301-975-4203, kham@nist.gov)
Special Assistance Available

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MEETINGS ELSEWHERE


1/12 -- MONDAY

11:00 AM - CARNEGIE INSTITUTION OF WASHINGTON/GEOPHYSICAL LAB. SEMINAR: REDUCED COHN VOLATILES IN SILICATE MELTS: IMPLICATIONS FOR THEIR CHEMICAL AND ISOTOPIC EVOLUTION IN THE SILICATE EARTH
B. Mysen , GL.
Bldg, Rm..
Greenewalt Bldg., GL-DTM Grounds, Carnegie Institution of Washington, DC. (NIST Contact: M. Fogel, 202-478-8900, seminar@lists.ciw.edu)



1/13 -- TUESDAY

No Scheduled Events

1/14 -- WEDNESDAY

No Scheduled Events

1/15 -- THURSDAY

No Scheduled Events

1/16 -- FRIDAY

No Scheduled Events

ADVANCE NOTICE

No Scheduled Events

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TALKS BY NIST PERSONNEL

SIMMON, E. : ROHS/REACH DATA EXCHANGE STANDARDS UPDATE.
Department of Commerce, Washington, DC USA, 1/13.

CLARK, C. : RELATIVITY AT A BILLIONTH OF THE SPEED OF LIGHT.
Physics Dept., Univ. of Maryland, College Park, MD, 1/13.

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ANNOUNCEMENTS

SIXTEENTH ANNUAL SIGMA XI POSTDOCTORAL POSTER PRESENTATION (PPP) CALL FOR POSTERS
The NIST Chapter of Sigma Xi invites all Post-Doctoral Fellows to present a poster on their scientific research to their NIST coworkers and friends. Guest Scientists who have received their advanced degree in the last five years are also welcome. There will be two sessions – Session I from 9 am until noon and session II – from 1 pm until 4 pm. Both sessions will take place on February 11, 2009 in Lecture Rooms A and B and the adjoining hallway in the Administration Building and will be accompanied by refreshments. All the participating Post-docs and Guest Scientists will be invited to a special reception in the Employees Lounge on February 20 when the awards for the most outstanding posters will be announced. Registration this year is $10. To participate, please register by sending a check payable to the NIST Chapter of Sigma Xi or cash to Dr. Darwin Reyes (NIST Chapter of Sigma Xi, Mail Stop 8120) and send an abstract of your poster in MS Word and the author information listed below to yuqin.zong@nist.gov Please format your abstract as follows: (TITLE all caps, followed by full authors' names, underline all authors who are postdocs and/or eligible guest workers followed by the text – not more than 300 words). The author information should be on another page and must include: Your Name, Mentor's name, Division, Laboratory, Room and Building address, Mail Stop, Telephone #, FAX #, email and whether you and/or your mentor are Sigma Xi members. You must choose a category that best describes your poster: Biology, Biotechnology, Chemistry, Engineering, Materials, Mathematics, or Physics. A template will soon be available on the Sigma Xi Web page where abstracts from previous years can also be seen (http://www.nist.gov/sigmaxi). THE DEADLINE FOR ABSTRACTS IS JANUARY 15, 2009. Posters in each session will be numbered according to the time of their receipt. Space this year is even more limited than last year, so please sign up early.
NIST Contact: Jason Gardner, 301-975-8391, jsg@nist.gov

NCNR SEMINAR ON HYDROGEN STORAGE
Speaker: Eric Poirier Institute: General Motors Corporation/ Purdue University Title: Investigation of Hydrogen Adsorption in Different Nanoporous Materials over Wide Ranges of Pressure and Temperature Place: NCNR, Bldg. 235, Room E100 Date: Jan. 15, 2009 Time: 10:45 am Abstract: Experimental investigations of hydrogen adsorption on different nanoporous materials over wide ranges of pressure and temperature are presented. In a first part, rigorous gravimetric and volumetric methods developed to measure hydrogen adsorption on single-walled carbon nanotubes (SWNTs) are presented. These systems were especially adapted for measurements on small masses and in-situ conditioning. Cross-checked measurements using these methods showed that SWNTs adsorb hydrogen according to mechanisms comparable to other forms of carbons. In a second part, experimental and theoretical methods implemented to study hydrogen adsorption thermodynamics on different metal-organic frameworks (MOFs) are presented. It was found that the best material, MOF-177, can adsorb up to 12.6 wt% at 10 bar and 50 K. This capacity decreases, however, with increasing temperature as a result of weak solid-gas interactions (DeltaH~3-4 kJ/mol). For the lowest measured temperatures, the near-saturation regions of the excess isotherms were used to calculate the adsorbed phase density and volume, two usually eluding quantities. In all tested materials, the adsorbed phase density was found to behave like an incom¬pressible fluid and to reach a density comparable to that of the bulk liquid hydrogen. This conjunction of liquid state properties, exceptional above the critical temperature, could be explained by a traditional micropore filling model. These properties suggest that repulsive interactions and quantum effects could be important limiting factors for the molecular storage of hydrogen under nanoscale confinement.
NIST Contact: Taner Yildirim, 301-975-6228, taner@nist.gov

CALL FOR NOMINATIONS NIST GALLERY OF DISTINGUISHED SCIENTISTS, ENGINEERS, AND ADMINISTRATORS
The NIST Portrait Gallery of Distinguished Scientists, Engineers and Administrators honors NBS/NIST alumni for outstanding career contributions to the work of NBS/NIST. Portraits and biographies of those selected are displayed in the corridor of the NIST cafeteria at Gaithersburg. Portraits of at most ten additional persons will be added to the Portrait Gallery in 2009. Any current or former NIST staff member may make a nomination. Nominations are welcome for alumni who were administrators of either programmatic or support units. SAA also encourages nominations of distinguished female and minority alumni, as well as of outstanding NBS staff members who retired before 1963. For the latter, it is understood that some requested data may no longer be available. For persons who were nominated last year, but not selected, a new nomination may be submitted. If a nominee is not selected after two successive years of nomination, the nominee will not be considered in the following year. Nomination instructions are available from the Standards Alumni Association (SAA), Room A-42 Admin, Mail Stop 0952, NIST, Gaithersburg, MD 20899-0952; telephone 301-975-2486; by email: alumni@nist.gov; or from the SAA website: www.nist.gov/director/saa. Nominations shall be received by the Standards Alumni Association on or before February 13, 2009, by mail or by email to the above addresses. No exceptions will be made to this deadline.
NIST Contact: Hans Oser, 301-975-2486, hans.oser@nist.gov

VISITOR REGISTRATION FOR NIST EVENTS
Because of heightened security at the NIST Gaithersburg site, members of the public who wish to attend meetings, seminars, lectures, etc. must first register in advance. For more information please call or e-mail the "NIST Contact" for the particular event you would like to attend.
NIST Contact: . ., ., .

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NIST WEB SITE ANNOUNCEMENTS

No Web Site announcements this week.

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For more information, contact Ms. Sharon Hallman, Editor, Stop 2500, National Institute of Standards and Technology, Gaithersburg MD 20899-2500; Telephone: 301-975-TCAL (3570); Fax: 301-926-4431; or Email: tcal@nist.gov.

All lectures and meetings are open unless otherwise stated.

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