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151.
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153.
空中爆炸冲击波对生物目标的超压-冲量准则 总被引:1,自引:0,他引:1
针对空中爆炸冲击波对生物目标的毁伤准则问题,超压-冲量毁伤准则可弥补单一毁伤准则的缺陷。首先,根据空中爆炸冲击波特征参量的一般形式,提出一种归一化毁伤准则形式,给出基于毁伤律的毁伤准则与判据的获取方法。其次,在不同爆炸条件对生物目标进行毁伤效应实验,依据生物整体的损伤情况确定出毁伤等级,对应获得的离散的实验数据确定连续性的超压-冲量曲线,继而拟合出不同毁伤等级的超压-冲量准则的表达式,所得到的超压-冲量准则可以评估生物目标的毁伤问题。 相似文献
154.
155.
Water-in-oil (w/o) microemulsions of methyl methacrylate (MMA), acrylic acid (AA), sodium acrylamidostearate (NaAAS), and water were investigated. MMA, AA, and NaAAS could be terpolymerized in these microemulsions. For a composition of 54% MMA, 34% AA, 2% NaAAS, and 10% H2O, polymers of high molecular weights of about 1,000,000 were obtained between 3.5 to 24% polymer conversion. The system became a transparent gel when conversion exceeded 36%. Transparent solid terpolymer containing water up to 16% were also obtained after fully polymerizations of certain compositions. 相似文献
156.
Peirong Chen Ly May Chew Aleksander Kostka Kunpeng Xie Martin Muhler Wei Xia 《天然气化学杂志》2013,(2):312-320
Oxygen-and nitrogen-functionalized carbon nanotubes (OCNTs and NCNTs) were applied as metal-free catalysts in selective olefin hydrogenation. A series of NCNTs was synthesized by NH3 post-treatment of OCNTs. Temperature-programmed desorption, N2 physisorption, Raman spectroscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy were employed to characterize the surface properties of OCNTs and NCNTs, aiming at a detailed analysis of the type and amount of oxygenand nitrogen-containing groups as well as surface defects. The gas-phase treatments applied for oxygen and nitrogen functionalization at elevated temperatures up to 600 C led to the increase of surface defects, but did not cause structural damages in the bulk. NCNTs showed a clearly higher activity than the pristine CNTs and OCNTs in the hydrogenation of 1,5-cyclooctadiene, and also the selectivity to cyclooctene was higher. The favorable catalytic properties are ascribed to the nitrogen-containing surface functional groups as well as surface defects related to nitrogen species. In contrast, oxygen-containing surface groups and the surface defects caused by oxygen species did not show clear contribution to the hydrogenation catalysis. 相似文献
157.
Shuxiang Wang Wenhao Chu Yuechai Wang Siyuan Liu Jinchao Zhang Shenghui Li Haiying Wei Guoqiang Zhou Xinying Qin 《应用有机金属化学》2013,27(7):373-379
Eight novel Pt(II), Pd(II), Cu(II) and Zn(II) complexes with 4’‐substituted terpyridine were synthesized and characterized by elemental analysis, UV, IR, NMR, electron paramagnetic resonance, high‐resolution mass spectrometry and molar conductivity measurements. The cytotoxicity of these complexes against HL‐60, BGC‐823, KB and Bel‐7402 cell lines was evaluated by MTT assay. All the complexes displayed cytotoxicity with low IC50 values (<20 μm ) and showed selectivity. Complexes 3 , 5 , 7 and 8 exerted 9‐, 5‐, 12‐ and 7‐fold higher cytotoxicity than cisplatin against Bel‐7402 cell line. The cytotoxicity of complexes 3 , 5 , 6 , 7 and 8 was higher than that of cisplatin against BGC‐823 cell line. Complexes 3 , 7 and 8 showed similar cytotoxicity to cisplatin against KB cell line. Complex 7 exhibited higher cytotoxicity than cisplatin against HL‐60 cell line. Among these complexes, complex 7 demonstrated the highest in vitro cytotoxicity, with IC50 values of 1.62, 3.59, 2.28 and 0.63 μm against HL‐60, BGC‐823, Bel‐7402 and KB cells lines, respectively. The results suggest that the cytotoxicity of these complexes is related to the nature of the terminal group of the ligand, the metal center and the leaving groups. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
158.
The development of an interactive simulation program generator which is available on micro and mainframe computers is outlined. The generator forms part of a simulation environment being researched into and constructed by a group of researchers at the London School of Economics. The generated programs are written in Pascal, using a suite of routines which assume a three-phase structure for simulation programs. Experiences of modelling using such a simulation modelling environment are outlined, as well as details of related research and future research plans. 相似文献
159.
A New Differential Lattice Boltzmann Equation and Its Application to Simulate Incompressible Flows on Non-Uniform Grids 总被引:1,自引:0,他引:1
A new differential lattice Boltzmann equation (LBE) is presented in this work, which is derived from the standard LBE by using Taylor series expansion only in spatial direction with truncation to the second-order derivatives. The obtained differential equation is not a wave-like equation. When a uniform grid is used, the new differential LBE can be exactly reduced to the standard LBE. The new differential LBE can be applied to solve irregular problems with the help of coordinate transformation. The present scheme inherits the merits of the standard LBE. The 2-D driven cavity flow is chosen as a test case to validate the present method. Favorable results are obtained and indicate that the present scheme has good prospects in practical applications. 相似文献
160.
In vivo sodium-23 magnetic resonance surface coil imaging: Observing experimental cerebral ischemia in the rat 总被引:2,自引:0,他引:2
Michael E. Moseley Ph.D. Wil M. Chew B.S. Merry C. Nishimura B.S. Todd L. Richards Ph.D. Joseph Murphy-Boesch Ph.D. Gregory B. Young Ph.D. Thomas M. Marschner Ph.D. Lawrence H. Pitts M.D. Thomas L. James Ph.D. 《Magnetic resonance imaging》1985,3(4):383-387
Sodium-23 magnetic resonance imaging can be used to detect and assess experimental cerebral ischemia in the rat. An imaging technique utilizing a surface coil is described to produce sodium magnetic resonance images of good quality and resolution within 10 min. A novel method of hemispheric occlusion showed edema in the right brain of the rat head within 3 hr after injury. The edema was especially pronounced by 12 hr with effects in the right brain, eye and surrounding muscle evident. 相似文献