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Katarzyna E. Bielska, Daniel K. Havey, Gregory E. Scace, D Lisak, Allan H. Harvey, Joseph T. Hodges
The vapor pressure of hexagonal (Ih) ice was measured over the temperature range 175 K to 253.4 K and referenced to the value at the triple point of water. This experiment combined a highly accurate humidity generation system containing an ice-coated
Jeffrey S. Nico, A. T. Yue, Maynard S. Dewey, David M. Gilliam, G L. Greene, A. Laptev, William M. Snow, F. E. Wiefeldt
The most precise determination of the neutron lifetime using the beam method was completed in 2005 and reported a result of tau_n = (886.3 ± 1.2 [stat] ± 3.2 [sys]) s. The dominant uncertainties were attributed to the absolute determination of the fluence
Arsenic has been measured in food and food supplement Standard Reference Materials by neutron activation analysis for the purpose of value-assigning As mass fractions and assessing homogeneity. Instrumental neutron activation analysis (INAA) has been used
Thomas H. Gnaupel-Herold, Mark A. Iadicola, Adam A. Creuziger, Timothy J. Foecke, Lin Hu
Biaxial yield behavior is determined in-situ through X-ray lattice strain measurements. The distributions of d-spacings in different sample directions is affected both by the changes in diffraction elastic constants (DEC) from evolving texture and by the
Jason M. Simmons, Jeremy Cook, Richard M. Ibberson, Charles Majkrzak, Dan Neumann
A design for a continuous source, polychromatic beam powder neutron diffractometer based on an energy-dispersive detection methodology is proposed. Such an instrument would offer significantly higher incident neutron flux, with an attendant increase in
Sebnem Inceoglu, Nicholas P. Young, Andrew J. Jackson, Steven Kline, Stephane Costeux, Nitash P. Balsara
Small-angle neutron scattering was used to study a binary blend of styrene-acrylonitrile copolymer (SAN) and deuterated poly(methyl methacrylate) (dPMMA), as wellas a multicomponent mixture of SAN, dPMMA, and supercritical carbon dioxide (scSO 2). The
Thomas R. Gentile, M E. Hayden, P.J. Nacher, A K. Petukhov, B Saam, T G. Walker
H.H. Chen et al [1] claim that adding 4He to spin-exchange optical pumping (SEOP) cells confines 3He atoms to a diffusion-limited region, which effectively reduces the wall relaxation factor X. Here X is a phenomenological parameter used to characterize
Daniel S. Hussey, Elias M. Baltic, Kevin J. Coakley, David L. Jacobson
This in-situ study examines the water content in polymer electrolyte fuel cells (PEFCs) using neutron radiography. Various conditions such as different polytetraflouroethylene (PTFE) loadings in the gas diffusion media including the micro-porous layer (MPL
Sangcheol Kim, Joseph A. Dura, Kirt A. Page, Christopher L. Soles
We quantify the interfacial structure and corresponding water transport kinetics in thin films of Nafion using neutron reflectivity (NR) and quartz-crystal microbalance (QCM) by integrating these measurements with in-situ, controlled relative humidity
Vivek M. Prabhu, Shrinivas Venkataraman, Ashlynn Lee, Yi Yan Yang, James Hedrick, Hareem Maune
In this study, a cholesterol functionalized aliphatic cyclic carbonate monomer, 2-(5-methyl-2-oxo-1,3-dioxane-5-carboxyloyloxy)ethyl carbamate (MTC-Chol) was synthesized. The organo-catalytic ring opening polymerization of MTC-Chol was accomplished by
We present a general theoretical framework on light-wave mixing and scattering in quantum gases. We show that all such processes that originate from elementary excitations are stimulated Raman or hyper-Raman in nature. In the forward direction, the third
First principles density functional theory DFT+U calculations and experimental neutron diffraction structure refinements were used to determine the low-temperature crystallographic and magnetic structure of bixbyite a-Mn2O3. The energies of various
Rick L. Paul, Hsiu-Wen Wang, David J. Wesolowski, Thomas E. Proffen, Lucus Vicek, Wei Wang, Lawrence F. Allard, Alexander I. Kolesnikov, Mikhail Feygenson, Lawrence M. Anovitz
The structure of SnO2 nanoparticles (avg. 5 nm diameter) with a few layers of water on the surface has been elucidated by atomic pair distribution function (PDF) methods using in situ neutron total scattering data and molecular dynamics (MD) simulations
Qiang NMN Ye, Thomas R. Gentile, Jeffrey R. Anderson, Collin L. Broholm, WangChun Chen, Z DeLand, Ross W. Erwin, C. B. Fu, John E. Fuller III, Aaron V. Kirchhoff, J. A. Rodriguez-Rivera, V. Thampy, T G. Walker, Shannon Watson
We report substantial improvements in a compact wide angle neutron spin filter system that was recently employed on the Multi-Axis Crystal Spectrometer at the Center for Neutron Research at the U.S. National Institute of Standards and Technology. The
Daniel S. Hussey, D. Liu, M. V. Gubarev, D Ramsey, David L. Jacobson, Muhammad D. Arif, D. E. Moncton, B. Khaykovich
An achromatic cold-neutron microscope with magnification 4 is demonstrated. The image-forming optics is made of nested coaxial mirrors of full figures of revolution, so-called Wolter optics. The spatial resolution, field of view, and depth of focus are
Sodium dodecyl sulfate (SDS) surfactants form micelles when dissolved in water. These are formed of a hydrocarbon core and hydrophilic ionic surface. The small-angle neutron scattering (SANS) technique was used with deuterated water (D 2O) in order to
Michael G. Huber, M. O. Abutaleb, Dimitry A. Pushin, Charles F. Majkrzak, Muhammad Arif, D G. Cory
We introduce a design of a neutron spin rotator for applications with space and temperature constraints. These passive devices employ remnant magnetization Fe- CoV thin films and can be tuned experimentally to achieve arbitrary rotation of an incident
Jeffrey S. Nico, T J. Langford, Christopher D. Bass, E J. Beise, D. K. Erwin, Craig Heimbach
We present a straightforward method for particle identification and background rejection in He-3 proportional counters for use in neutron detection. By measuring the risetime and pulse height of the preamplifier signals, one may define a region in the
Jeffrey S. Nico, C. D. Bass, E J. Beise, Craig Heimbach, T. Langford
We present the characterization of a liquid scintillator incorporating an aqueous solution of enriched lithium chloride to produce a scintillator with 0.40% 6Li. We report on its performance in terms of optical properties and neutron response. We
Leticia S. Pibida, Craig Heimbach, Bruce R. Norman, Alan Keith Thompson, Maynard S. Dewey
Initial neutron measurements and calculations were performed to investigate the response of handheld radionuclide identifiers (RIDs) to neutron sources with different moderators/scattering conditions
James A. Bartz, Cynthia J. Zeissler, V. V. Fomenko, Mark S. Akselrod
Fluorescent Nuclear Track Detector (FNTD) technology was tested as an imaging and spectroscopic tool for radionuclide analysis. This investigation intended to distinguish between characteristic α-particles of 239Pu (5.2 MeV), 234U (4.8 MeV) and 238U (4.2
Kushol Gupta, Joseph E. Curtis, Susan N. Krueger, Young Hwang, Peter Cherepanov, Frederic Bushman, Gregory D. Van Duyne
The recently determined crystal structures of prototype foamy virus integrase (PFV IN) in complex with viral DNA and target DNA reveal the first high-resolution insights into the nucleoprotein intermediates involved in retroviral integration. Using small