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21.
In this work we obtain positive singular solutions of where is a sufficiently small perturbation of the cone where has a smooth nonempty boundary and where satisfies suitable conditions. By singular solution we mean the solution is singular at the ‘vertex of the perturbed cone’. We also consider some other perturbations of the equation on the unperturbed cone Ω and here we use a different class of function spaces. 相似文献
22.
Cowan ML Anache-Ménier D Hildebrand WK Page JH van Tiggelen BA 《Physical review letters》2007,99(9):094301
Temporal fluctuations in the phase of waves transmitted through a dynamic, strongly scattering, mesoscopic sample are investigated using ultrasonic waves, and compared with theoretical predictions based on circular Gaussian statistics. The fundamental role of phase in diffusing acoustic wave spectroscopy is revealed, and phase statistics are also shown to provide a sensitive and accurate way to probe scatterer motions at both short and long time scales. 相似文献
23.
Photocatalytic Water Oxidation by a Pyrochlore Oxide upon Irradiation with Visible Light: Rhodium Substitution Into Yttrium Titanate 下载免费PDF全文
Borbala Kiss Dr. Christophe Didier Timothy Johnson Dr. Troy D. Manning Dr. Matthew S. Dyer Dr. Alexander J. Cowan Dr. John B. Claridge Prof. James R. Darwent Prof. Matthew J. Rosseinsky 《Angewandte Chemie (International ed. in English)》2014,53(52):14480-14484
A stable visible‐light‐driven photocatalyst (λ≥450 nm) for water oxidation is reported. Rhodium substitution into the pyrochlore Y2Ti2O7 is demonstrated by monitoring Vegard′s law evolution of the unit‐cell parameters with changing rhodium content, to a maximum content of 3 % dopant. Substitution renders the solid solutions visible‐light active. The overall rate of oxygen evolution is comparable to WO3 but with superior light‐harvesting and surface‐area‐normalized turnover rates, making Y2Ti1.94Rh0.06O7 an excellent candidate for use in a Z‐scheme water‐splitting system. 相似文献
24.
D. O. Cowan R. Gleiter O. Glemser E. Heilbronner J. Schuublin 《Helvetica chimica acta》1971,54(6):1559-1564
The photoelectron spectrum of thiazyl fluoride has been recorded. An assignment of the first five bands has been attempted, using semi-empirical calculations. 相似文献
25.
An aluminum reflection grating made holographically was found to display polarization anomalies when illuminated with p-polarized light. Additional anomalies were detected for both p- and s-polarizations after the grating was coated with a layer of dielectric (410 nm of photoresist). These new anomalies have been interpreted in terms of the optical guided modes of a thin film dielectric waveguide bounded on one side by metal and on the other by vacuum. 相似文献
26.
The low temperature (125K) X-ray crystal structures of (TMTSF)2X, X=C104-, PF6-, and AsF6- reveal decreases in the intermolecular interand intrastack Se-Se contact distances upon cooling (298K to 125K) which are highly anisotropic and different from one salt to another. The changes in the interstack distances, which are normal to the stacking direction, are approximately twice those involving intrastack Se-Se interactions. These observations establish that the anisotropic structural changes which accompany decreased temperature are common to numerous (TMTSF)2X radical cation conducting salts. 相似文献
27.
James Cowan 《Acoustical Physics》2005,51(4):484-485
Chronicle
In memory of V.I. Zaborov (March 16, 1927–August 30, 2004) 相似文献28.
Background
Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH. 相似文献29.
Abe K Abe K Abe T Adam I Akimoto H Aston D Baird KG Baltay C Band HR Barklow TL Bauer JM Bellodi G Berger R Blaylock G Bogart JR Bower GR Brau JE Breidenbach M Bugg WM Burke D Burnett TH Burrows PN Calcaterra A Cassell R Chou A Cohn HO Coller JA Convery MR Cook V Cowan RF Crawford G Damerell CJ Daoudi M de Groot N de Sangro R Dong DN Doser M Dubois R Erofeeva I Eschenburg V Fahey S Falciai D Fernandez JP Flood K Frey R Hart EL Hasuko K Hertzbach SS Huffer ME Huynh X Iwasaki M Jackson DJ 《Physical review letters》2003,90(14):141804
We present an improved direct measurement of the parity-violation parameter A(b) in the Z boson-b-quark coupling using a self-calibrating track-charge technique applied to a sample enriched in Z-->bb events via the topological reconstruction of the B hadron mass. Manipulation of the Stanford Linear Collider electron-beam polarization permits the measurement of A(b) to be made independently of other Z-pole coupling parameters. From the 1996-1998 sample of 400,000 hadronic Z decays, produced with an average beam polarization of 73.4%, we find A(b)=0.906+/-0.022(stat)+/-0.023(syst). 相似文献
30.
Gomez L Slutzky C Ferron J de La Figuera J Camarero J Vazquez De Parga AL de Miguel JJ Miranda R 《Physical review letters》2000,84(19):4397-4400
Generic computer simulations using empiric interatomic potentials suggest a new, collective mechanism that could be responsible for mixing at heteroepitaxial interfaces. Even if single adsorbate atoms diffuse by hopping on the substrate surface and do not mix at the terraces, two-dimensional islands formed by nucleation may become unstable above a certain critical size and explode upwards forming clusters of several atomic layers. This process is accompanied by strong distortions of the underlying atomic layers, and on soft materials it can result in surface etching and incorporation of substrate atoms into the islands. 相似文献