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101.
Deeney C Apruzese JP Coverdale CA Whitney KG Thornhill JW Davis J 《Physical review letters》2004,93(15):155001
Nested-wire array experiments have been conducted at the 7 MA level with 150 ns implosion times from an outer diameter of 40 mm. Analysis of spectral data indicates that material from the outer array preferentially occupies the high temperature core of the stagnated pinch independent of the interwire gap in the range of 1.1 to 4.5 mm. 相似文献
102.
We say that a subset of Cn is hypoconvex if its complement is the union of complex hyperplanes. We say it is strictly hypoconvex if it is smoothly bounded
hypoconvex and at every point of the boundary the real Hessian of its defining function is positive definite on the complex
tangent space at that point. Let Bn be the open unit ball in Cn.Suppose K is a C∞ compact manifold in ∂B1 × Cn, n > 1, diffeomorphic to ∂B1 × ∂Bn, each of whose fibers Kz over ∂B1 bounds a strictly hypoconvex connected open set. Let K be the polynomialhull of K. Then we show that K∖K is the union of
graphs of analytic vector valued functions on B1. This result shows that an unnatural assumption regarding the deformability of K in an earlier version of this result is
unnecessary. Next, we study an H∞ optimization problem. If pis a C∞ real-valued function on ∂B1× Cn, we show that the infimum γρ = infƒ∈H
∞ (B1)n ‖ρ(z, ƒ (z))‖∞ is attained by a unique bounded ƒ provided that the set (z, w) ∈ ∂B1 × C n|ρ(z, w) ≤ γρ has bounded connected strictly hypoconvex fibers over the circle. 相似文献
103.
This review consolidates biological activity data reported for pyridoacridine 1 molecules in the literature from 1983-2003 into several tables with brief discussions of assays used and results obtained. This review summarizes recent progress in structure activity relationships for analogues of amphimedine 2 and ascididemin 3 classes of pyridoacridines and correlates reported molecular mechanisms of action with biological activities. 相似文献
104.
Towards quantum superpositions of a mirror 总被引:1,自引:0,他引:1
We propose an experiment for creating quantum superposition states involving of the order of 10(14) atoms via the interaction of a single photon with a tiny mirror. This mirror, mounted on a high-quality mechanical oscillator, is part of a high-finesse optical cavity which forms one arm of a Michelson interferometer. By observing the interference of the photon only, one can study the creation and decoherence of superpositions involving the mirror. A detailed analysis of the requirements shows that the experiment is within reach using a combination of state-of-the-art technologies. 相似文献
105.
Håkansson K Hudgins RR Marshall AG O'Hair RA 《Journal of the American Society for Mass Spectrometry》2003,14(1):23-41
We report electron capture dissociation (ECD) and infrared multiphoton dissociation (IRMPD) of doubly protonated and protonated/alkali metal ionized oligodeoxynucleotides. Mass spectra following ECD of the homodeoxynucleotides polydC, polydG, and polydA contain w or d "sequence" ions. For polydC and polydA, the observed fragments are even-electron ions, whereas radical w/d ions are observed for polydG. Base loss is seen for polydG and polydA but is a minor fragmentation pathway in ECD of polydC. We also observe fragment ions corresponding to w/d plus water in the spectra of polydC and d(GCATGC). Although the structure of these ions is not clear, they are suggested to proceed through a pentavalent phosphorane intermediate. The major fragment in ECD of d(GCATGC) is a d ion. Radical a- or z-type fragment ions are observed in most cases. IRMPD primarily results in base loss, but backbone fragmentation is also observed. IRMPD provides more sequence information than ECD, but the spectra are more complex due to extensive base and water losses. It is proposed that the smaller degree of sequence coverage in ECD, with fragmentation mostly occurring close to the ends of the molecules, is a consequence of a mechanism in which the electron is captured at a P=O bond, resulting in a negatively charged phosphate group. Consequently, at least two protons (or alkali metal cations) must be present to observe a w or d fragment ion, a requirement that is less likely for small fragments. 相似文献
106.
Hyperuricosuria has long been documented as a predisposing factor to calcium oxalate (CaOx) stone pathogenesis. However, its mechanism is still without sound scientific foundation. Previously, we showed that hyperuricosuria, simulated by the addition of dissolved sodium urate, promotes the crystallization of CaOx. In the present study, we demonstrate that the urate's effect on the crystallization is attributable to its salting out CaOx from solution. Furthermore, analysis of urines revealed that their metastable limit decreased with increases in the product of the prevailing concentrations of calcium and urate: this has implications for CaOx stone genesis. We also outline anti-salting out strategies for future research for the prevention and/or treatment of CaOx calculi. 相似文献
107.
[reaction: see text] Treatment of 1-iodomethyl-1,5-bis-epoxides with zinc in refluxing ethanol affords cis or trans 2-vinyl-5-(1-hydroxyethy)-substituted tetrahydrofurans stereospecifically in high yield. 相似文献
108.
Congreve MS Ladlow M Marshall P Parr N Scicinski JJ Sheppard T Vickerstaffe E Carr RA 《Organic letters》2001,3(4):507-510
[reaction: see text] An analytical construct resin, designed to aid the analysis of solid-phase chemistry, has been mixed in a small proportion with a conventional resin. The analytical construct ("reporter resin") contains two orthogonal linkers that allow cleavage of either the synthetic intermediates (at linker 2) or their analytically enhanced derivatives (at linker 1). The convenient and rapid monitoring of each step in the syntheses of representative library compounds was possible using small resin aliquots. 相似文献
109.
Porcelli TA Adamczak A Bailey JM Beer GA Douglas JL Faifman MP Fujiwara MC Huber TM Kammel P Kim SK Knowles PE Kunselman AR Maier M Markushin VE Marshall GM Mason GR Mulhauser F Olin A Petitjean C Zmeskal J;TRIUMF Muonic Hydrogen Collaboration 《Physical review letters》2001,86(17):3763-3766
Measurements of muon-catalyzed dt fusion ( d(mu)t-->4He + n + mu(-)) in solid HD have been performed. The theory describing the energy dependent resonant molecular formation rate for the reaction (mu)t + HD-->[(d(mu)t)pee](*) is compared to experimental results in a pure solid HD target. Constraints on the rates are inferred through the use of a Monte Carlo model developed specifically for the experiment. From the time-of-flight analysis of fusion events in 16 and 37 microg x cm(-2) targets, an average formation rate consistent with 0.897+/-(0.046)(stat)+/-(0.166)(syst) times the theoretical prediction was obtained. 相似文献
110.
J. Marshall Ash Sh. T. Tetunashvili 《Proceedings of the American Mathematical Society》2000,128(9):2627-2636
A uniqueness theorem is proved for trigonometric series and another one is proved for multiple trigonometric series. A corollary of the second theorem asserts that there are two subsets of the -dimensional torus, the first having a countable number of points and the second having points such that whenever a multiple trigonometric series ``converges' to zero at each point of the former set and also converges absolutely at each point of the latter set, then that series must have every coefficient equal to zero. This result remains true if ``converges' is interpreted as any of the usual modes of convergence, for example as ``square converges' or as ``spherically converges.'