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Abbasi RU Abu-Zayyad T Amann JF Archbold G Bellido JA Belov K Belz JW Bergman DR Cao Z Clay RW Cooper MD Dai H Dawson BR Everett AA Fedorova YA Girard JH Gray RC Hanlon WF Hoffman CM Holzscheiter MH Hüntemeyer P Jones BF Jui CC Kieda DB Kim K Kirn MA Loh EC Manago N Marek LJ Martens K Martin G Matthews JA Matthews JN Meyer JR Moore SA Morrison P Moosman AN Mumford JR Munro MW Painter CA Perera L Reil K Riehle R Roberts M Sarracino JS Sasaki M Schnetzer SR Shen P Simpson KM Sinnis G Smith JD 《Physical review letters》2004,92(15):151101
We have measured the cosmic ray spectrum above 10(17.2) eV using the two air-fluorescence detectors of the High Resolution Fly's Eye observatory operating in monocular mode. We describe the detector, phototube, and atmospheric calibrations, as well as the analysis techniques for the two detectors. We fit the spectrum to a model consisting of galactic and extragalactic sources. 相似文献
24.
A. Bremner R. Calderbank P. Hanlon P. Morton J. Wolfskill 《Journal of Number Theory》1983,16(2):212-234
This paper determines the parameters of all two-weight ternary codes C with the property that the minimum weight in the dual code C⊥ is at least 4. This yields a characterization of uniformly packed ternary [n, k, 4] codes. The proof rests on finding all integer solutions of the equation y2 = 4 × 3a + 13. 相似文献
25.
Phil Hanlon 《Journal of Algebraic Combinatorics》1996,5(3):245-250
Let S be a signed poset in the sense of Reiner [4]. Fischer [2] defines the homology of S, in terms of a partial ordering P (S) associated to S, to be the homology of a certain subcomplex of the chain complex of P (S).In this paper we show that if P (S) is Cohen-Macaulay and S has rank n, then the homology of S vanishes for degrees outside the interval [n/2, n].Research partially supported by the National Science Foundation and the John Simon Guggenheim Foundation. 相似文献
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M Pattabiraman G Rangarajan Kwang-Yong Choi P Lemmens G Guentherodt G Balakrishnan DMcK Paul MR Lees 《Pramana》2002,58(5-6):1013-1017
We report polarized Raman scattering in single crystals of Nd0.7Sr0.3MnO3. The temperature dependence of the MnO6 octahedral bending and stretching modes observed in the XX spectra points to the existence of local lattice distortions,
possibly polarons. The XY spectra have been analyzed using a collision-dominated model, which allows the extraction of the
carrier scattering rate. 相似文献
28.
George M. Janini Gary M. Muschik Carol M. Hanlon 《Molecular Crystals and Liquid Crystals》2013,570(1-2):15-27
The synthesis, phase transition temperatures and thermodynamic data (enthalpies and entropies) are reported for the methoxy through n-octyloxy (and n-decyloxy) homologues of the liquid crystal series represented by N,N′-bis[p-alkoxybenylidene]-α, aα′-bi-p-toluidine. The trends in transition temperatures are more or less analogous to previously-studied liquid crystal series. Nematic-isotropic enthalpy values are appreciably higher than average values for other series. Entropy values show the usual odd-even effect, but in contrast to observed trend for other series, they decrease with increasing terminal substituent chain length. Di-Schiff' s bases with various terminal substituents that showed interesting linear correlation between nematicisotropic transition temperatures and the anisotropy of polarizability of the substituent were also synthesized. A simple gas-liquid chromatographic method for the investigation of the selectivity of nematic stationary phases and its dependence on the degree of molecular order in the nematic state is also presented. 相似文献
29.
Corinne Hanlon Shaun Frape Rhys Gwynne 《Isotopes in environmental and health studies》2017,53(5):446-465
This study provides the first characterization of the variability of bromine and chlorine stable isotopic composition in evaporites, associated residual brines, and shoreline gases in terrestrial evaporative saline lakes. The lakes investigated here are groundwater discharge locations, and include both potash-rich alkaline lakes and sodic-dominated neutral pH lakes at a variety of salinities and evaporative stages. The chlorine and bromine isotope systems behave consistently different during evaporative salt precipitation, with 37Cl more enriched in the salt than in the fluid, but 81Br more enriched in the fluid compared with the precipitated salt. The 81Br concentration of shore off-gassing was even smaller than mineral precipitate compositions. The trends observed for bromine isotopes are surprising compared with published laboratory studies, indicating that a process besides inorganic mineral precipitation is affecting δ81Br. Additional processes explored include diffusion, salt deflation, microbial and photolytic conversion to the gas phase, and oxidative bromination of organic matter.
Dedicated to Professor Peter Fritz on the occasion of his 80th birthday 相似文献
30.
A new antibiotic, pseudomonic acid C (2a), has been isolated from fermentations of the strain of which produces the known and structurally similar antibiotics pseudomonic acids A (1a) and B (1c). 相似文献