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Eric P. Vetter, Liwei Geng, Priya Ghatwai, Dustin A. Gilbert, Yongmei Jin, William A. Soffa, Jerrold A. Floro
The Co-Pt nanochessboard is a quasi-periodic, nanocomposite tiling of Ll 0 and Ll 2 magnetic phases that offers a novel structure for the investigation of exchange coupling, relevant to permanent magnet applications. Periodicity of the tiling is controlled
In this study, the attraction between the large hard polystyrene (PS) spheres is studied by using three types of small microgels as bridging agents. One is purely soft poly(N-isopropylacrylamide) (PNIPAM) microgel, the other two have an indeformable PS
Hui Wu, Wan Si NMN Tang, Wei Zhou, Jacob Daniel Tarver, Vitalie Stavila, Craig Brown, Terrence J. Udovic
Two ordered phases of the novel solid superionic conductor sodium 1-carba-closo-decaborate (NaCB 9H 10) were identified via synchrotron x-ray powder diffraction in combination with first-principles calculations and neutron vibrational spectroscopy. A
Ryan Poling-Skutvik, Katrina Irene S. Mongcopa, Antonio Faraone, Suresh Narayanan, Jacinta C. Conrad, Ramanan Krishnamoorti
We investigate the structure and dynamics of silica nanoparticles and polymer chains in semidilute solutions of high molecular weight polystyrene in 2-butanone to determine the effect of long range interparticle interactions on the coupling between
Methane adsorption onto the model mesoporous silica materials in the size range characteristic of shale is studied by small-angle neutron scattering (SANS). Size effect on the temperature-dependent gas adsorption is investigated by SANS using MCM-41 and
Jing Yu, Jun Mao, Guangcui Yuan, Sushil K. Satija, Zhang Jiang, Wei Chen, Matthew Tirrell
Polyelectrolyte brushes are of great importance to a wide range of fields, ranging from colloidal stabilization to responsive and tunable materials to lubrication. We synthesized high-density polystyrene sulfonate (PSS) brushes using surface force
Danyal J. Turkoglu, Robert G. Downing, Wangchun Chen, Dagistan Sahin, Jeremy C. Cook
Prompt gamma-ray activation analysis facilities with high neutron currents (≥109 s-1) generate triton-induced fast neutrons from 6Li-loaded collimators and beam stops at rates that soon damage gamma-ray detectors. We develop an alternative beam stop design
M. L. Taheri, Eric Stach, Ilke Arslan, Peter A. Crozier, Kabius Bernd, Thomas LaGrange, Andrew Minor, Seiji Takeda, Mihaela M. Tanase, Jakob B. Wagner, Renu Sharma
This review article discusses the current and future possibilities for the application of in situ transmission electron microscopy to reveal synthesis pathways and functional mechanisms in complex and nanoscale materials. The findings of a group of
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