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71.
Renaud Beaudegnies Alain De Mesmaeker Aurélie Mallinger Myriam Baalouch André Goetz 《Tetrahedron letters》2010,51(20):2741-3222
We report the design and the efficient synthesis of novel spirocyclopropyl cyclohexane-1,3-dione and -1,3,5-trione units to be incorporated into potent HPPD inhibitors. New routes involving original combinations of synthetic equivalents of α-cyclopropyl ketone-α-anion and α-cyclopropyl ester-β-cation are described. 相似文献
72.
73.
V.E. Panin V.S. Pleshanov S.A. Kobzeva S.P. Burkova 《Theoretical and Applied Fracture Mechanics》1998,29(2):99-102
Studied is the mesoscale behavior of plastic deformation and fracture of weld joints for austenic steels. Large-scale rotational modes of deformation in heat affected zones are identified with the first stage of formation of band structures; it is related to the “traveling neck” phenomenon in the base metal. The second stage is connected with crack generation and the state of affairs in the heart-affected zone. 相似文献
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75.
We shall determine the 20 families of irreducible even triangulations of the projective plane. Every even triangulation of the projective plane can be obtained from one of them by a sequence of even‐splittings and attaching octahedra, both of which were first given by Batagelj 2 . © 2007 Wiley Periodicals, Inc. J Graph Theory 56: 333–349, 2007 相似文献
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77.
Martin Ochsner Thomas Fleck Peter Kernen David A. Deranleau Josef Pfeilschifter 《Journal of fluorescence》1992,2(1):37-45
The intracellular free Ca2+ concentration ([Ca2+]i) could be correlated with the contractile response in rat mesangial cells using an apparatus which measured both biochemical processes simultaneously. Long-term pretreatment of mesangial cells with 12-O-tetradecanoly-phorbol 13-acetate (24 h, 500 nM) increased the (20 nM) angiotensin II-induced mobilization of Ca2+ and led to an enhanced and sustained contraction of the cells. The contractile response was delayed by approximately 3.5 s with respect to the intracellular increase in Ca2+ concentration. The simultaneous registration of Ca2+ transients and cell contractions confirms that [Ca2+]i is the major determinant of the angiotensin II-mediated mesangial cell contraction.Dedicated to Professor Horst H. A. Linde on the occasion of his 60th birthday. 相似文献
78.
用概率断裂力学方法预测管状接头的疲劳寿命 总被引:1,自引:1,他引:0
本文研究了T型管状接头在面内和面外弯曲循环载荷作用下的疲劳强度问题,通过将材料常数和初始裂纹尺寸作为随机变量,采用MonCarlo模拟方法对疲劳寿命进行了统计分析.同时,对计算结果进行了线性回归,并与实验结果作了比较。 相似文献
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80.
In this paper, we study mixed non-linear fractional delay differential equations with integral boundary conditions. We obtain an equivalence result between the proposed problem and non-linear Fredholm integral equation of the second kind. Further, we establish existence and uniqueness of positive solutions for the problem using Guo-Krasnoseleskii''s fixed point theorem and Banach contraction principle. 相似文献