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Portions of the Hf-Pd phase diagram have been reinvestigated in an attempt to resolve contradictions that occur between two previous studies. Techniques employed include Rietveld refinement using x-ray and high-temperature neutron diffraction data to
Jeffrey S. Nico, Kevin J. Coakley, Maynard S. Dewey, Thomas R. Gentile, Hans P. Mumm, Alan Keith Thompson, M J. Bales, R. Alarcon, C. D. Bass, E J. Beise, H Breuer, Jim Byrne, R L. Cooper, B. O'Neill, F E. Wietfeldt, T E. Chupp
The theory of quantum electrodynamics predicts that a continuous spectrum of photons is emitted in the beta decay of the free neutron in addition to a proton, an electron, and an antineutrino. We report the first precision test of the shape of the photon
Arunima Singh, Kiran Mathew, Joshua Grabriel, Kamal Choudhary, Susan B. Sinnott, Albert Davydov, Francesca M. Tavazza, Richard G. Hennig
A Materials Project based open-source python tool, MPInterfaces, has been developed to automate the high throughput computational screening and study of interfacial systems. The framework encompasses creation and manipulation of interface structures for
Neutron imaging applications exploit the power of neutrons to penetrate through metals and measure small concentrations of hydrogen and lithium with high sensitivity. The recent advances made in digital imaging devices have enabled many novel neutron
Vivek M. Prabhu, Vytautas Reipa, Adam Rondinone, Peter V. Bonnesen, Eric Formo
An in situ electrochemical small-angle neutron scattering (eSANS) method was developed to measure simultaneously the redox properties and size, shape and interactions of solution-dispersed nanomaterials. By combining multi-step potentials and
The Feynman relation 1, a much celebrated condensed matter physics gemstone for more than 70 years, predicts that the density excitation spectrum and structure factor of a condensed Bosonic system in the phonon regime drops linear and continuously to zero
Andrew J. Luhmann, Benjamin Tutolo, Brian C. Bagley, David F. Mildner, Jr. Seyfried, Martin O. Saar
Four reactive flow-through laboratory experiments (two each at 0.1 ml/min and 0.01 ml/min flow rates) at 150 °C have been conducted on intact basalt cores to assess changes in porosity, permeability, and surface area caused by CO 2-rich fluid-rock
Michael G. Huber, Muhammad D. Arif, David G. Cory, R. Haun, B. Heacock, Joachim Nsofini, Dimitry A. Pushin, P Saggu, C.B Shahi, William M. Snow, A.R. Young
The physical origin of the dark energy which causes the accelerated expansion rate of the universe is one of the major open questions of cosmology. One set of theories postulates the existence of a self-interacting scalar eld for dark energy coupling to
T.J. Langford, E J. Beise, H Breuer, Craig Heimbach, G Ji, Jeffrey S. Nico
We present the development of a segmented fast neutron spectrometer (FaNS-2) based upon plastic scintillator and He-3 proportional counters. It was designed to measure both the flux and spectrum of fast neutrons in the energy range of few MeV to 1 GeV
Vivek M. Prabhu, Shrinivas Venkataraman, Yi Yan Yang, James Hedrick
Summary: ABA-type oligo fluorene-carbonate end-functionalized polyethylene glycols form micelles with star-like correlations in dilute solutions where water solvates the middle (B) poly(ethylene oxide) block. Using small-angle neutron scattering (SANS)
Huagen H. Peng, Vikram Daga, Ying Lin, J J. Watkins, Wen-Li Wu, Christopher Soles
The addition of linear poly (acrylic acid) (PAA) to a disordered low molecular mass poly (ethylene oxide)-poly (propylene oxide)-poly (ethylene oxide) triblock copolymer host (PEO-b-PPO-b-PEO) is known to induce an ordering transition. Small angle neutron
A closed-atmosphere, solvent-recirculating, large diameter wafer washer was fabricated for neutron reflectivity research at the National Institute of Standards and Technology. Manufacturing feasibility for the public sector was increased by simplicity in
Vivek M. Prabhu, Shrinivas Venkataraman, Yi Yan Yang, James Hedrick
Small-angle neutron scattering and static and dynamic light scattering have characterized the hierar-chical structure and dynamics of clusters of self-assembled star-like micelles formed by oligocarbonate-fluorene func-tionalized polyethylene glycol
J L. Blasic, David L. Worcester, Klaus Gawrisch, Philip A. Gurnev, Mihaela Mihailescu
Water-filled hydrophobic cavities of channel proteins serve as gateways for transfer of ions across membrane. However, functional implications of hydration-dehydration transitions remain elusive due to difficulties to detect and quantify water in channel
Xiaohang NMN Zhang, Peter J. Lowell, Brandon L. Wilson, Galen C. O'Neil, Joel N. Ullom
In this paper, we demonstrate a general-purpose macroscopic refrigerator based on the transport of hot electrons through superconducting tunnel junctions. Our refrigerator is intended to provide access to temperatures below those accessible using pumped
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
Ultra-pure, carrier-free 209Po solution standards have been prepared and standardized for their massic alpha-particle emission rate. The standards, which will be disseminated by the National Institute of Standards and Technology (NIST) as Standard
Daniel S. Hussey, Christoph W. Brocker, David L. Jacobson, Thomas R. Gentile, Wangchun Chen, Elias M. Baltic, DV Baxter, J. Doskow, Muhammad D. Arif
The NIST neutron imaging program will build a new imaging instrument in the NCNR guide hall at the end of the neutron guide NG-6, beginning operation in summer of 2014. The NG-6 guide has a spectrum that is strongly peaked at a neutron wavelength of 5 Å
Neutron reflectometry is uniquely positioned in structural biology, because of its ability to characterize biomimetic interfacial architectures like lipid membranes and membrane-associated proteins non-destructively and in their native environment
Andrew J. Allen, Laura Espinal, Winnie K. Wong-Ng, Wendy Queen, Craig Brown, Steven R. Kline, Kristi L. Kauffman, Jeffrey T. Culp
Results from in situ experiments are presented to correlate carbon capture with dynamic structural changes in two flexible metal-organic framework (MOF) materials: porous coordination polymers (PCPs) exhibiting promising carbon dioxide adsorption
Rick L. Paul, Rabia Oflaz, Jan Kucera, J W Bennett, E. A. De Nadai Fernandes, M. Kubesova, M. A. Bacchi, A. J. Stopic, R. E. Sturgeon, P. Grinberg
Instrumental neutron activation analysis with both relative and k0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube certified reference material (CRM) SWCNT-1. Results obtained
Rick L. Paul, Dagistan NMN Sahin, Jeremy C. Cook, Christoph W. Brocker, Richard M. Lindstrom, Donna J. O'Kelly
A new instrument for cold neutron prompt gamma-ray activation analysis (CNPGAA) has been designed and constructed as part of the recent expansion of the cold neutron guide hall at the NIST Center for Neutron Research (NCNR). Located on neutron guide NGD
As part of an international project to benchmark facilities for measuring the strain dependence of critical current in ITER Nb 3Sn strands, direct measurement of local strain exerted on Nb 3Sn filaments was attempted at cryogenic temperature by means of
Ana Trapote-Barreira, Lionel Porcar, Jordi Cama, J. M. Soler, Andrew J. Allen
Flow-through experiments were conducted to study the calcium-silicate-hydrate (C-S-H) gel dissolution kinetics under a CO2-free atmosphere at room temperature (22 ± 2) ºC in the pH range from 10 to 13 relevant to cement media. During C-S-H gel dissolution
Lee L. Yu, Rolf L. Zeisler, Rabia Oflaz, Wei Chao, Junting Tong, Haixia Bao, Jun Wang
The National Institute of Standards and Technology is developing a kelp standard reference material (SRM) in support of dietary supplement measurements. Edible seaweeds such as kelp and laver consumed as diet or dietary supplement contain tens of mg/kg
Prasad S. Sarangapani, Steven D Hudson, Ronald L. Jones, Jack F. Douglas, Jai A. Pathak
Recent studies of globular protein solutions have uniformly adopted a colloidal view of proteins as particles, a perspective that neglects the polymeric primary structure of these biological macromolecules, their intrinsic flexibility and their ability to