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CreatorTitleDescriptionSubjectDate
126 Rogachev, AndreyAdmittance spectroscopy study of polymer diodes in small magnetic fieldsWe performed a systematic study of bipolar and unipolar organic diodes based on the p-conjugated polymer, 2-methoxy-5-(20-ethylhexyloxy) (MEH-PPV), using electronic and magneto-transport measurements with magnetic field in the range 0-180mT and admittance spectroscopy in the frequency range 1 Hz<f<1...2012-01-01
127 Gondolo, PaoloCosmic ray positron excess and neutralino dark matterUsing a new instrument, the HEAT Collaboration has confirmed the excess of cosmic ray positrons that they first detected in 1994. We explore the possibility that this excess is due to the annihilation of neutralino dark matter in the galactic halo. We confirm that neutralino annihilation can produ...Neutralinos; Supersymmetric models; Positron flux; Annihilations2002-02
128 Bohs, Lynn A.ITS phylogeny of Balsamorhiza and Wyethia (Asteraceae: Heliantheae)The relationships among the species of Balsamorhiza and Wyethia (Asteraceae: Heliantheae) were examined using data from the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA. The ITS sequences were obtained from nine species of Balsamorhiza and 14 species of Wyethia as well as se...Asteraceae; Balsamorhiza; Heliantheae; Internal transcribed spacer; ITS; Molecular phylogeny; Wvethi2003
129 Adler, Frederick R.; Liou, Theodore G.Use of lung transplantation survival models to refine patient selection in cystic fibrosisLung transplantation in cystic fibrosis may improve survival for patients with low 5-year predicted survival. Identifying characteristics that affect post-transplantation survival may improve patient selection and survival benefit. Using Cystic Fibrosis Foundation Patient Registry and United Network...Lung transplation; Survival; Burkholderia cepacia2005
130 DeTar, CarletonQCD thermodynamics with two flavors at Nt=6The first results of numerical simulations of quantum chromodynamics on the Intel iPSC/860 parallel processor are presented. We performed calculations with two flavors of Kogut-Susskind quarks at Nt = 6 with masses of 0.15T and 0.075T (0.025 and 0.0125 in lattice units) in order to locate the crosso...Kogut-Susskind quarks; Crossover temperature; Chiral symmetry; Polyakov loop; Phase transitions1992-05
131 Miller, Joel Steven; Epstein, Arthur J.Ferrimagnetic resonance in films of vanadium [tetracyanoethanide]x, grown by chemical vapor depositionFerrimagnetic resonance (FMR) measurements in thin films of V[TCNE]x grown by chemical vapor deposition exhibit a series of sharp lines at 300 K. The orientational dependence of these lines is a result of the sample geometry provided the magnetization tracks the applied magnetic field. The FMR inten...Spin; Anisotropy; Magnetization2004
132 Saam, Brian; Laicher, GernotNuclear spin relaxation of 129Xe due to persistent xenon dimersWe have measured longitudinal nuclear relaxation rates of 129Xe in Xe-N2 mixtures at densities below 0.5 amagats in a magnetic field of 8.0 T. We find that intrinsic spin relaxation in this regime is principally due to fluctuations in the intramolecular spin-rotation (SR) and chemical-shift-anisot...Nuclear spin relaxation; Xe129; Xenon dimmers2006-12
133 Capecchi, Mario R.Male fertility is dependent on dipeptidase activity of testis ACE.Testis angiotensin-converting enzyme (ACE) is an isozyme exclusively expressed by developing sperm. This protein has only a single catalytic domain containing the HEXXH consensus-site motif typical of zinc metallopeptidases. The exact role of testis ACE is unknown, but male mice lacking the protein ...Amino Acid Motifs; Blotting, Western; Catalytic Domain; Comparative Study; Isoenzymes; Protein Structure, Tertiary2005-11-11
134 Miller, Joel Steven; Epstein, Arthur J.Proton spin-lattice and spin-spin relaxation times of (N(CH3)3)H)(I)(TCNQ)Proton spin-lattice T(1) and spin-spin T(2) relaxation times are reported for (N(CH(3))(3)H)(I)(TCNQ) in the temperature range 150 to 5OOK. The overall relaxation process of the system can be described by contributions from rotation of the N(CH3)3H+ group about its symmetry axis, tumbling of that g...Transition; Reorientation; Conductivity1978
135 Ailion, David CharlesStudy of utraslow atomic motions by magnetic resonanceMagnetic resonance has been widely used to study phenomena such as atomic diffusion and molecular reorientation. It is applicable when the mean time, r, between atomic jumps is either (a) sufficiently short to narrow the resonance line width or (b) of the correct magnitude to produce spin-lattice ...Atomic motion; Magnetic resonance; Ultraslow atomic motion1964
136 Sokolsky, PierreBackward production in π-p→pπ+π-π- at 8 GeV/c*We have studied backward baryon and meson production in π'p → pπ+pπ +π-π- at 8.0 GeV/c using a streamer chamber triggered by the detection of a fast forward proton. Our data sample (1227 events) displays prominent N*p and N*f quasi-two-body production. These states are investigated with rega...1976-01
137 Sperry, John S.Size and function in conifer tracheids and angiosperm vesselsThe wide size range of conifer tracheids and angiosperm vessels has important consequences for function. In both conduit types, bigger is better for conducting efficiency. The gain in efficiency with size is maximized by the control of conduit shape, which balances end-wall and lumen resistances.Ecological wood anatomy; vascular structure and function; water transport2006
138 Miller, Joel Steven; Epstein, Arthur J.Effect of disorder on the linear and nonlinear magnetic susceptibilities of two manganeseporphryin-based magnetsWe analyze the effects of disorder on the magnetic properties of two manganeseporphyrins, [MnTPP][TCNE] •. x(o-DCB) and [MnTPP][TCNE] . • y(o-Xy) and (TPP=meso-tetraphenylporphyrinato, TCNE=tetracyanoethylene, o-Xy=o-xylene, o-DCB=o-dichlorobenzene, x<_3,y<_1). We present data for the in- ...Magnetization; Ferrimagnetic; Spins1997
139 Lupton, John MarkMechanisms of spin-dependent dark conductivity in films of a soluble fullerene derivative under bipolar injectionWe report room-temperature pulsed electrically detected magnetic resonance measurements of the dark conductivity of films of the fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) under bipolar (electron-hole) and unipolar (electron-rich) injection conditions. Directly after mate...2014-01-01
140 Williams, Clayton C.Two-dimensional scanning capacitance microscopy measurements of cross-sectioned very large scale integration test structuresScanning probe technology, with its inherent two-dimensionality, offers unique capabilities for the measurement of electrical properties on a nanoscale. We have developed a setup which uses scanning capacitance microscopy (SCM) to obtain electrical information of cross-sectioned samples while simul...Oxide capacitance; Dopant profile; Scanning capacitance microscopy1996-01
141 Miller, Joel Steven; Epstein, Arthur J.Decamethylchromocenium tetracyanoethenide, + [Cr(C5Me5)2]:.+[TCNE].-: a molecular ferromagnet with Tc=3.65 KThe electron-transfer salt 4[Cr(C5Me5)2] + [TCNE].-(TCNE = tetracyanoethylene) has been prepared and structurally characterized by single-crystal X-ray diffraction. It possesses a solid-state motif of parallel 1D chains of alternating radical cations and anions similar to, but not isostructural to, ...Magnetic; Electron transfer; Coupling1993
142 Miller, Joel Steven; Epstein, Arthur J.Specific heat of decamethylferrocenium tetracyanoethanide (DMeFc)(TCNE)We report the specific heat C(T) of (DMeFc)(TCNE) for temperatures 3 K < T < 50 K. We observe an anomaly at Tc-4.82 K corresponding to a transition to a three-dimensional (3D) macroscopic ferromagnet. A broad maximum at = 15 K corresponds to an exchange interaction of J = 35 K along the chain axis. ...Temperature; Ferromagnetic; Magnetic1989
143 Kieda, David B.Observation of the shadows of the moon and sun using 100 TeV cosmic raysThe Chicago Air Shower Array (CASA) is a large ground-based scintillation detector [1-4]. It is located at the Dugway Proving Ground is west central Utah, latitude 40°N and mean atmospheric depth 870 g / c m 2. A schematic aerial view of CASA is shown in Fig. 1. Each dot represents one scintil...Chicago Air Shower Array; Scintillation detectors; Ultrahigh energy cosmic rays1994-02
144 Adler, Frederick R.Effect of 1918 PB1-F2 expression on influenza A virus infection kineticsRelatively little is known about the viral factors contributing to the lethality of the 1918 pandemic, although its unparalleled virulence was likely due in part to the newly discovered PB1-F2 protein. This protein, while unnecessary for replication, increases apoptosis in monocytes, alters viral po...2011
145 Adler, Frederick R.Effect of 1918 PB1-F2 expression on influenza A virus infection kineticsAbstract Relatively little is known about the viral factors contributing to the lethality of the 1918 pandemic, although its unparalleled virulence was likely due in part to the newly discovered PB1-F2 protein. This protein, while unnecessary for replication, increases apoptosis in monocytes, alter...2011
146 DeTar, CarletonRecent MILC spectrum results*We report on results from three spectrum calculations with staggered quarks: 1) a quenched calculation with the standard action for the gluons and quarks; 2) a quenched calculation with improved actions for both the gluons and quarks; and 3) a calculation with two flavors of dynamical quarks using...Staggered quarks; Hadron spectrum1997-02
147 DeTar, CarletonResults for light pseudoscalars from three-flavor simulationsWe compute pseudoscalar meson masses and decay constants in partially quenched QCD with three dynamical flavors of improved staggered quarks. Fitting the lattice data to staggered chiral perturbation theory (SX_x001F_PT) forms and extrapolating in quark mass and lattice spacing, we find: frr = 129...Pseudoscalars; Decay constants; Staggered quarks2005-03
148 Armentrout, Peter B.Endothermic reactions of uranium ions with N2, D2, and CD4The assessment of new technology for isotope separation has revived an interest in the spectroscopy, properties, and reactions of uranium and its compounds. Newer methods which have been demonstrated include the use of lasers to selectively excite a particular uranium isotope with subsequent chemic...Uranium ions; Nitrogen1977
149 Armentrout, Peter B.Reaction of Cr+, Mn+, Fe+, Co+, and Ni+ with O2 and N2O. Examination of the translational energy dependence of the cross sections of endothermic reactionsReactions of Cr+, Mn+, Fe+, Co+, and Ni+ with 02 and N20 to yield metal oxide ions are examined using an ion beam apparatus. Reaction cross sections a as a function of ion translational energy E are reported. With one exception, Fe+ + N20, the cross sections exhibit an energy threshold E0.Metal oxides; Endothermic reactions; Translational energy; Bond energy; Threshold energy1982
150 Golden, Kenneth M.Broad spectral, interdisciplinary investigation of the electromagnetic properties of sea iceThis paper highlights the interrelationship of research completed by a team of investigators and presented in the several individual papers comprising this Special Section on the Office of Naval Research (ONR), Arlington, VA, Sponsored Sea Ice Electromagnetics Accelerated Research Initiative (ARI).Scattering; Radiation; EM1998
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