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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
Andrew J. Allen, Janos Hajdu, Anke R. Kaysser-Pyzalla
It is now one year since all International Union of Crystallography (IUCr) journals became online only, and this is just one of the developments during the International Year of Crystallography, IYCr 2014. Perhaps, most conspicuously, IUCrs new flagship
Dagistan Sahin, Vladimir Radulovic, Richard M. Lindstrom, Andrej Trkov
It has been difficult to characterize the thermal to epithermal neutron flux ratio (f) and the measure of the nonideal epithermal neutron flux distribution (α) for the RT-2 pneumatic rabbit facility at the NIST National Bureau of Standards Reactor (NBSR)
E. Talik, L. Lipinska, A. Guzik, Pawel Zajdel, M. Michalska, M. Szubka, M. Kadziolka-Gawel, Rick L. Paul
The Pechini sol-gel method was applied to obtain LiMn 2-xT xO 4 (T=Ni, Fe; x = 0.1 to 0.5) nanopowders. Crystal and electronic structures, chemical composition and magnetic properties of the materials were characterized by X-ray diffraction, XPS, SEM/EDX
Allan D. Carlson, V G. Pronyaev, R. Capote, G M. Hale, F. J. Hambsch, T Kawano, S. Kunieda, W Mannhart, R O. Nelson, D. Neudecker, P Schillebeeckx, S Simakov, P Talou, X Tao, D. L. Smith, W Wang, A. Wallner
A number of national cross section libraries are planning new versions of their libraries including ENDF/B and JEFF. The first step in producing these new libraries is evaluating the neutron standards. A new evaluation of the standards is now underway
Allan D. Carlson, V G. Pronyaev, R. Capote, G M. Hale, F. J. Hambsch, T Kawano, S. Kunieda, R O. Nelson, D. Neudecker, P Schillebeeckx, S Simakov, D L. Smith, X Talou, A Wallner, W Wang
A new version of the ENDF/B library has been planned. The first step in producing this new library is evaluating the neutron standards. An evaluation is now underway with support from a Data Development Project of the IAEA. In addition to the neutron cross
Thomas R. Gentile, M J. Bales, H Breuer, T E. Chupp, Kevin J. Coakley, R L. Cooper, Jeffrey S. Nico, B. O'Neill
We present measurements of nonproportionality in the scintillation light yield of bismuth germanate (BGO) for gamma-rays with energies between 6 keV and 662 keV. The scintillation light was read out by avalanche photodiodes (APDs) with both the BGO
Jeffrey S. Nico, T J. Langford, Christopher D. Bass, H Breuer, Craig Heimbach, D. K. Erwin
A fast neutron spectrometer consisting of segmented plastic scintillator and He-3 proportional counters was constructed for the measurement of neutrons in the energy range 1 MeV to 200 MeV. We discuss its design, principles of operation, and the method of
Maynard S. Dewey, V. Gressier, A. C. Bonaldi, David M. Gilliam, H. Harano, A. Masuda, T Matsumoto, N. Moiseev, Jeffrey S. Nico, R. Notle, S. Oberstedt, N. J. Roberts, S. Rottger, D. J. Thomas
To ensure the validity of their national standards, National Metrology Institutes, NMIs, participate regularly in international comparisons. In the area of neutron metrology, Section III of the Consultative Committee for Ionizing Radiation is in charge of
The deterioration of stone and brick architecture or sculpture often involves damage caused by moisture. The feasibility of a non-destructive testing (NDT) method based on prompt gamma neutron activation (PGNA) for measuring the element hydrogen as an
Michael G. Huber, Muhammad D. Arif, Christopher Wood, D G. Cory, M. O. Abutaleb, Dimitry A. Pushin
We investigate quantum coherences in the presence of noise by entangling the spin and path degrees of freedom of the output neutron beam from a noisy three-blade perfect crystal neutron interferometer. We nd that in the presence of dephasing noise on the
Matthew N. Martin, Andrew J. Allen, Robert I. MacCuspie, Vincent A. Hackley
Little is understood about the impact coating molecules have on nanoparticle dissolution kinetics and intermediate agglomerate formation in a dilute nanoparticle dispersion. Dissolution and agglomeration processes compete in removing isolated nanoparticles
Thomas R. Gentile, T G. Walker, E Babcock, Qiang NMN Ye, Wangchun Chen
Using diode bar lasers spectrally narrowed with chirped volume holographic gratings (VHGs), we have obtained an improvement in the 3He polarization achievable by spin-exchange optical pumping (SEOP). As compared to our past results with lasers narrowed
Antonio Faraone, Emiliano Fratini, Somenath Garai, Achim Muller, Madhu Sudan Tyagi, Timothy Jenkins, Eugene Mamontov, Rick L. Paul, John R. Copley, Piero Baglioni
The single particle relaxation dynamics of hydrogen atoms in different oxomolybdate Keplerate type nanocages characterized by a (metal) 30 icosidodecahedron and a size of {approximately equal}25 A were studied using Incoherent Quasielastic Neutron
In a previous work Sims and Hagstrom [Phys. Rev. A 83,032518(2011)] reported Hylleraas-configuration-interaction (Hy-CI) method variational calculations for the singlet S ground state of neutral beryllium with an estimated accuracy of a tenth of a
Alan K. Thompson, Jacob McComb, Charles W. Clark, Michael A. Coplan, Mohamad Al-Sheikhly, Robert E. Vest
Far-ultraviolet (FUV) scintillation signals have been measured in heavy noble gases (argon, krypton, xenon) following boron-neutron capture (10B(n,α)7Li) in 10B thin films. The observed scintillation yields are comparable to the yields from some liquid and
After a brief introduction, the Neutron Resonance Spin Echo (NRSE) principle is discussed classically in Sec. 2. In Sec. 3, two idealized 4-coil NRSE spectrometers are discussed (one using single π coil units and one using paired "bootstrap" coils), some