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41.
The oxygenation reaction of cholesteryl acetate 1 was examined with the Fe(III)(PA)(3)/O(2)/MeCN system using an electrochemical method. The constant potential technique gave mainly the 7-hydroxylated product stereoselectively, along with the 7-oxo product. This oxygenation system is mechanistically unique, requiring iron catalyst, dioxygen, and both cathode and anode.  相似文献   
42.
Summary We introduce a martingale problem to associate diffusion processes with a kind of nonlinear parabolic equation. Then we show the existence and uniqueness theorems for solutions to the martingale problem.Research partially supported by the Air Force Office of Scientific Research Contract No. F4962082C0009  相似文献   
43.
In this paper we introduce a new consistency condition and provide characterizations for several solution concepts in TU cooperative game theory. Our new consistency condition, which we call the random reduction consistency, requires the consistency of payoff vectors assigned by a solution concept when one of the players is removed with some probability. We show that the random reduction consistency and other standard properties characterize the Weber set, the convex hull of the marginal contribution vectors. Another salient feature of random reduction consistency is that, by slightly changing its definition, we can characterize the core and the anti-core in a parallel manner. Our result enables us to compare the difference between the three solution concepts from the viewpoint of consistency.  相似文献   
44.
For near-future applications of REBa2Cu3O7 (REBCO) coated conductors to electric power cables, transformers and Superconducting Magnetic Energy Storage (SMES), the long taped wires with high performance in the transport properties have been designed and fabricated. Moreover, in order to drastically reduce AC losses in perpendicular field configuration, advanced multifilament YBCO coated conductors (MFYCCs) fabricated with technique of a laser scribing process have been also developed. In the present study, from engineering viewpoints to utilize such advanced conductors, we evaluated the transport and AC loss properties of short MFYCCs with a repaired part or a joint by a diffusion joint technique with the saddle-shaped pickup coil method.  相似文献   
45.
The normalized elimination of the small component (NESC) theory, recently proposed by Filatov and Cremer, is extended to include magnetic interactions and applied to the calculation of the nuclear magnetic shielding in HX (X=F, Cl, Br, I) systems. The NESC calculations are performed at the levels of the zeroth-order regular approximation (ZORA) and the second-order regular approximation (SORA). The calculations show that the NESC-ZORA results are very close to the NESC-SORA results, except for the shielding of the I nucleus. Both the NESC-ZORA and NESC-SORA calculations yield very similar results to the previously reported values obtained using the relativistic infinite-order two-component coupled Hartree-Fock method. The difference between NESC-ZORA and NESC-SORA results is significant for the shieldings of iodine.  相似文献   
46.
47.
[2.n](2,6)Pyridinocrownophanes (3a-e) were efficiently prepared by intramolecular [2 + 2] photocycloaddition of vinylpyridine derivatives under irradiation using a 400-W high-pressure mercury lamp through a Pyrex filter. They were of cis-configuration with respect to the cyclobutane ring, which was proven by the specific methine proton NMR resonances at delta 3.98-4.08. From ESI-MS analysis 3a-e were found to form 1:1 complexes with Ag+ cation. In a liquid-liquid extraction, 3 showed the highest affinity toward Ag+ cation among several heavy metal nitrates. In this series, 3c possessing four ethereal oxygen atoms was found to show the highest Ag+ affinity, according to the liquid-liquid extraction and determination of stability constant with the cation. The photoreactivity of precursor vinylpyridines is discussed by the predictor gamma(r(c)) proposed by Caldwell.  相似文献   
48.
49.
We consider a linear heat equation on a half line with an additive noise chosen properly in such a manner that its invariant measures are a class of distributions of Lévy processes. Our assumption on the corresponding Lévy measure is, in general, mild except that we need its integrability to show that the distributions of Lévy processes are the only invariant measures of the stochastic heat equation.  相似文献   
50.
In this paper we characterize a value, called a marginalistic value, for monotonic set games, which can be considered to be the analog of the Shapley value for TU-games. For this characterization we use a modification of the strong monotonicity axiom of Young, but the proof is rather different from his.  相似文献   
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