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Brian J. Kirby, Joseph E. Davies, Kai Liu, Shannon Watson, G. T. Zimanyi, Robert D. Shull, Paul A. Kienzle, Julie A. Borchers
It has been theoretically predicted that depth-grading the magnetic anisotropy in perpendicular magnetic media should reduce the field required to write data, without affecting the thermal stability. To study this prediction, we have produced a series of
Benjamin Ueland, Jason S. Gardner, A. J. Williams, M. L. Dahlberg, J.G. Kim, Yiming Qiu, John R. Copley, P. Schiffer, R J. Cava
Neutron scattering and magnetization measurements have been performed on the stuffed pyrochlore system Tb 2+xTi 2-2xNb xO 7. We find that despite the introduction of chemical disorder and increasingly antiferromagnetic interactions, cooperative
Jong Keun Park, Paul J. Jones, Chris Sahagun, Kirt A. Page, Daniel S. Hussey, David L. Jacobson, Sarah E. Morgan, Robert B. Moore
While ionic polymer metal composites (IPMCs) have been studied for more than 10 years, the specific actuation mechanism is still unclear. In this work, neutron imaging, applied potential (AP) and current sensing (CS) atomic force microscopy (AFM) methods
Xiaohua Zhang, Kevin G. Yager, Shuhui Kang, Nathaniel J. Fredin, Bulent Akgun, Sushil K. Satija, Jack F. Douglas, Alamgir Karim, Ronald L. Jones
We utilize neutron reflectometry (NR) to probe the amount of residual solvent inside thin polystyrene (PS) and poly(methyl methacrylate) (PMMA) films spin-coated from deuterated toluene polymer solutions onto silicon substrates . The effect of thermal
Matt S. Munson, James Spotts, Antti Niemisto, Jyrki Selinummi, Jason G. Kralj, Marc L. Salit, Adrian Ozinsky
We have developed a fully automated control system to distribute user-defined numbers of antibody-functionalized fluorescent beads (scalable from tens to hundreds) to addressable assay chambers within a microfluidic PDMS device. We report an automated bead
E Babcock, Stephen Boag, Maria Becker, W.C. Chen, T E. Chupp, Thomas R. Gentile, G L. Jones, A K. Petukhov, Torsten Soldner, T G. Walker
Polarized 3He produced by spin-exchange optical pumping (SEOP) has potential as a neutron spin filter for polarization and polarization analysis in many neutron scattering and neutron particle physics applications. The advantage of the SEOP method is its
Rick L. Paul, Elizabeth A. Mackey, Rolf L. Zeisler, Rabia Oflaz, Bryan E. Tomlin
A combination of instrumental neutron activation analysis (INAA) and prompt gamma-ray activation analysis (PGAA) was used to value assign 35 elements in SRM soil 2709a (San Joaquin Soil). INAA with counting of short-lived radioisotopes was used for
The National Institute of Standards and Technology (NIST) developed new gamma-ray and neutron emitting sources for testing radiation detection systems. These sources were developed for testing of detection systems in maritime applications. This requires
Michael A. Hickner, Nathan P. Siegel, Ken S. Chen, Daniel S. Hussey, David L. Jacobson
The generation and transport of water in both the liquid and gas phases during device operation is an important area of study to understand both steady-state and transient performance of proton exchange membrane fuel cells. Specifically, localized high
Instrumental neutron activation analysis (INAA) as carried out at the National Institute of Standards and Technology (NIST) is inadequate for de-termining Al, Ni, and V at the levels found in the newly prepared Standard Reference Material (SRM) 1577c
R Cooper, Christopher D. Bass, E Beise, H Breuer, Jim Byrne, T E. Chupp, Kevin Coakley, Maynard S. Dewey, B Fisher, Changbo Fu, Thomas R. Gentile, M. McGonagle, Hans Pieter Mumm, Jeffrey S. Nico, Alan Keith Thompson, F E. Wietfeldt
The neutron typically beta decays into a proton, electron, and antineutrino. In some decays, it can be accompanied by a high energy photon. We recently performed the rst observation of the radiative beta decay branch for the free neutron with photons of
Thomas R. Gentile, E Babcock, Stephen Boag, C. Becham, T E. Chupp, Gordon L. Jones, A K. Petukhov, T G. Walker
Prior studies revealed neutron beam-induced alkali-metal spin relaxation in 3He cells polarized in-situ by spin-exchange optical pumping. These effects are minor for neutron beams of low to moderate intensity, but become important at the highest neutron
Andrew J. Allen, Jan Ilavsky, Fan Zhang, Gabrielle G. Long, Pete R. Jemian
Absolute calibration of small-angle scattering (SAS) intensity data (in units of differential cross-section per unit sample volume per unit solid angle) is essential for many important aspects of quantitative SAS analysis, such as obtaining the number
Nathaniel J. Fredin, Brian Berry, Kevin G. Yager, Alamgir Karim, Sushil K. Satija, Deanna Pickel, Ronald L. Jones
The development of methods that permit control over the long-range order and orientation of microdomains in block copolymer (BCP) thin films for bottom-up approaches to nanoscale surface patterning is of great interest for many applications, including
I. Cabrera, M. Kenzelmann, Wangchun Chen, Ross Erwin, Thomas R. Gentile, Juscelino Leao, Jeffrey W. Lynn, N. Rogado, R. J. Cava, C. Broholm, G. Lawes, Ying Chen
Electric control of spin chirality in a magnetically frustrated multiferroic is demonstrated through polarized magnetic neutron diffraction. Cooling to the cycloidal multiferroic phase of Ni ^ d3 ^ V ^ d2 ^ O ^ d8 ^ in an electric field causes the
Christine He, S. El-Khatib, J. Wu, Jeffrey Lynn, H. Zheng, J. F. Mitchell, C. Leighton
In recent years it has become clear that complex oxides provide an exceptional platform for the discovery of new physics as well as a considerable challenge to our understanding of correlated electrons. The tendency of these materials to display nanoscale
Robert D. Horansky, James A. Beall, Kent D. Irwin, Joel N. Ullom
Improving the resolution of gamma-ray detectors is important for many fields, including determinations of the Lamb shift in atoms with high atomic numbers , nuclear treaty verification , and environmental monitoring. High-purity germanium detectors are
Raymond Cao, Jason Hattrick-Simpers, Richard Bindel, Bryan E. Tomlin, Rolf L. Zeisler, Rick L. Paul, Leonid A. Bendersky, Robert G. Downing
Cold neutron prompt gamma activation analysis (PGAA) was used to determine the amount of hydrogen in thin film Mg hydrides with varying hydrogenation times. The results suggest that the hydrogenation in the Mg thin films remains unsaturated even after 48
M Huber, F.E. Weitfeld, Thomas R. Gentile, Wangchun Chen, Muhammad D. Arif, Dmitry Pushin, L Yang, T. Black
There is strong theoretical interest in the study of few-body nucleon systems. Experimental measurements of neutron scattering lengths are able to perform precise tests of nucleon-nucleon models. Neutron interferometry provides some of the most precise
Tae-Hwan Kim, Shin-Hyun Kang, Changwoo Doe, Jun-Bo Sim, Jehan Kim, Steven Kline, Sung-Min Choi
Self-assembly of 1D nanoparticles such as carbon nanotubes or nanorods into highly ordered superstructures using various interactions has been of great interest as a route toward materials with new functionalities. However, the phase behavior of 1D
R. G. Moore, M. D. Lumsden, M. B. Stone, Jiandi Zhang, Ying Chen, Jeffrey Lynn, R. Jin, D Mandrus, E. W. Plummer
Inelastic neutron scattering is used to measure the temperature-dependent phonon dispersion in Ca2−xSrxRuO4(x=0.4,0.6). The in-plane Σ4 octahedral tilt mode softens significantly at the zone boundary of the high-temperature tetragonal (HTT) I41/acd
J. A. Janik, H. D. Zhou, Y.-J. Jo, L. Balicas, G. J. MacDougall, G. M. Luke, J. D. Garrett, K. J. McClellan, E. D. Bauer, J. L. Sarrao, Yiming Qiu, John R. Copley, Z. Yamani, W. J. Buyers, C. R. Wiebe
By means of neutron scattering we show that the high-temperature precursor to the hidden order state of the heavy fermion superconductor URu 2Si 2 exhibits heavily damped incommensurate paramagnons whose strong energy dispersion is very similar to that of
Maynard S. Dewey, David M. Gilliam, Jeffrey S. Nico, G.L. Green, A. Laptev, A. Yue
The 6LI(N,T) and 10B(N,A) cross sections are important neutron cross section standards. Precise knowledge of these cross sections is essential because they are often used as reference standards for obtaining the neutron fluence in investigations of the
A new evaluation of the half-life of 241Pu has been made by developing earlier methods and techniques and employing further measurements of the isotopic ratio of an initially enriched 241Pu material. A correction to the previous value has had to be made