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111.
M Mitsukuchi T Ikemoto M Taguchi S Higuchi S Abe H Yasui K Hatayama K Sota 《Chemical & pharmaceutical bulletin》1989,37(12):3286-3293
A series of 21-thio derivatives of 9 alpha-fluoro-11 beta,17 alpha-dihydroxy-16 beta-methyl-1,4-pregnadiene-3, 20-dione 17-esters and related compounds were synthesized and evaluated as topical antiinflammatory agents. These compounds were prepared by the reaction of 9 alpha-fluoro-11 beta,17 alpha,21-trihydroxy-16 beta-methyl-1,4-pregnadiene-3, 20-dione (betamethasone, I) 17-ester derivatives and various mercapto compounds. A structure-activity relationship study revealed that the structural combination of a thio group at the 21-position and an ester group at the 17-position contributed to vasoconstrictive activity. Among these compounds, the 21-methylthio 17-propanoate compound (6) was found to have the most potent activity, being more potent than betamethasone 17-valerate (BV). 相似文献
112.
We study a matrix model obtained by dimensionally reducing Chern–Simons theory on S3. We find that the matrix integration is decomposed into sectors classified by the representation of SU(2). We show that the N -block sectors reproduce SU(N) Yang–Mills theory on S2 as the matrix size goes to infinity. 相似文献
113.
The existence of strong solutions of Cauchy problem for the following evolution equation du(t)/dt+∂?1(u(t))-∂?2(u(t))∋f(t) is considered in a real reflexive Banach space V, where ∂?1 and ∂?2 are subdifferential operators from V into its dual V*. The study for this type of problems has been done by several authors in the Hilbert space setting.The scope of our study is extended to the V-V* setting. The main tool employed here is a certain approximation argument in a Hilbert space and for this purpose we need to assume that there exists a Hilbert space H such that V⊂H≡H*⊂V* with densely defined continuous injections.The applicability of our abstract framework will be exemplified in discussing the existence of solutions for the nonlinear heat equation: where Ω is a bounded domain in RN. In particular, the existence of local (in time) weak solution is shown under the subcritical growth condition q<p* (Sobolev's critical exponent) for all initial data This fact has been conjectured but left as an open problem through many years. 相似文献
114.
New techniques to determined the localized-state density in chemically vapour deposited amorphous silicon over a wide energy range by the field-effect method are presented. The density is measured for the first time as 1018 ~ 1020 cm?3 eV?1 in the range ±0.4~±0.5 eV around the Fermi level. From the results it is suggested that the silicon atom network of CVD a-Si has a similar randomness to that of glow discharge a-Si, providing a density of tail states of about 1019 ~ 1020 cm?3 eV?1 and native defect states of about 1018 cm?3 eV?1. 相似文献
115.
Compacts of 7075 aluminum have been produced from rapidly solidified powders by optimizing spark sintering parameters, such as pulse discharge time, fixed maximum temperature, holding time at this temperature, and method of cooling to room temperature after the sintering. High-grade compacts can be obtained by a short process (40-50 s) consisting of heating to 773 or 873 K at a heating rate of 9.6 K/s and holding this temperature for 10 s. The rapidly cooled compacts show the same supersaturated state at room temperature as the received as-atomized powder. Compacts quenched in water just after spark sintering at 873 K for 1.2 ks show the same age-hardening behavior as solution-heat treated compacts. Compacts that are quenched in water and aged after sintering at 873 K for 1.2 ks show the same elongation and flow stress as compacts aged after solution heat treatment. Elongation data suggest that compacts produced with longer holding time at a higher temperature and rapid cooling show a large amount of main alloying elements in solid solution and sufficient promotion of sintering. 相似文献
116.
We have demonstrated the generation of the reflected four-wave mixed light in the energy region from 3.185 eV to 3.320 eV including the highly absorptive region due to the Z3 and Z1,2 exciton bands of CuCl at 1.6 K. The mixed light signal is concluded to be due to the one-photon resonant contribution of the respective exciton level, from its polarization characteristics. The corresponding third order non-linear susceptibility is estimated from the data by the correction with the Fresnel factors which are calculated on the basis of the Pekar's Additional Boundary Condition. 相似文献
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118.
Let , let , where g2 and g3 are coefficients of the elliptic curve: Y2 = 4X3 ? g2X ? g3 over a finite field and Δ = g23 ? 27g32 and let . Then the p-adic cohomology theory will be applied to compute explicitly the zeta matrices of the elliptic curves, induced by the pth power map on the free -module . Main results are; Theorem 1.1: X2dY and YdX are basis elements for ; Theorem 1.2: YdX, X2dY, Y?1dX, Y?2dX and XY?2dX are basis elements for , where is a lifting of X, and all the necessary recursive formulas for this explicit computation are given. 相似文献
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