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41.
Heterophase Photocatalysts from Water‐Soluble Conjugated Polyelectrolytes: An Example of Self‐Initiation under Visible Light 下载免费PDF全文
Saman Ghasimi Dr. Simon Prescher Zi Jun Wang Prof. Katharina Landfester Dr. Jiayin Yuan Dr. Kai A. I. Zhang 《Angewandte Chemie (International ed. in English)》2015,54(48):14549-14553
We herein report a new design route to stable, heterophase photocatalysts, which function as highly dispersible conjugated polymer nanoparticles and porous monoliths under visible light in aqueous medium. They were constructed by attachment of the ionic‐liquid species 1‐alkyl‐3‐vinylimidazolium bromide onto the side chains of a photoactive polymer. The structure configuration allows not only photocatalysis in aqueous environment but also a unique self‐initiation radical cross‐linking process to transform the water‐soluble photoactive polymer into a heterophase system, either as nanoparticles or a porous monolith. High photocatalytic activity and reusability of the heterophase system were demonstrated in the degradation of organic dyes and reduction of CrVI into CrIII in water under visible‐light irradiation. 相似文献
42.
本文报告了对常用高强材料30CrMnSiA的双边V型缺口疲劳门槛值进行的实验测量。通过测试结果分析,证实了对不同缺口半径的试样(△K1/√P)th基本一致的结论。 相似文献
43.
40Cr材料动态起裂韧性KId()的实验测试 总被引:4,自引:0,他引:4
描述了利用Hopkinson压杆技术加载三点弯曲试样测试40Cr,材料动态起裂韧性KId()的试验方法。试样上的动态载荷历程由Hopkinson杆直接测得,并分别代入动态有限元程序及近似公式求得动态应力强度因子历史;由贴在试样裂尖附近的应变片确定起裂时间,最终确定起裂时的动态应力强度因子值,即动态起裂韧性KId()。试验结果表明:利用Hopkinson压杆技术加载三点弯曲试样测试材料动态起裂韧性的方法是可行的,起裂时,动态有限元的位移法、应力法及近似公式法求得的动态应力强度因子值比较吻合;在本文的载荷速率下,40Cr材料动态起裂韧性KId()与准静态裂韧性KId()相比,降低了约28%。 相似文献
44.
A. D. Savel’ev 《Fluid Dynamics》2007,42(6):907-913
Supersonic laminar flow past a two-dimensional “flat-plate/wedge“ configuration is numerically investigated. The pressures at the boundary layer separation and reattachment points are calculated over wide Mach and Reynolds number ranges. The minimum angles of the wedge surface inclination at which a return flow occurs are determined. The results are presented in the form of generalized Mach-number-dependences of the theoretical pressure on the wedge surface initiating boundary layer separation and the pressure at the boundary layer reattachment point. 相似文献
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The use of numerical models has greatly increased our understanding of the electrical and microphysical process within electrified clouds. We use the University of Washington, 1.5-dimensional thunderstorm model to examine the effects of including a runaway electron based lightning initiation mechanism. We find that this mechanism can significantly alter the electrification history of modeled storms and produce vertical electric field profiles that are very similar to those of observed storms. To cite this article: R. Solomon et al., C. R. Physique 3 (2002) 1325–1333. 相似文献
49.
宽带泵浦激光的聚焦位置对SRS发生过程的影响 总被引:2,自引:0,他引:2
结合SRS实验,重点研究了聚焦位置对Raman介质中的物理过程、Stokes光的输出特性的影响,比较了SRS阈值和转换效率的实验结果与理论预期。 相似文献
50.
The thermal behavior of metal, oxide, and oxidizer mixtures, some with fluorine compound additions, has been studied in order to examine the influence of thermal properties on the initiation conditions for chemical reaction of pyrotechnic powders under dynamic loading conditions. The autoignition energies of the mixtures obtained from thermal analyses were compared with shock initiation energies, determined from planar shock measurements. Although some mixtures showed an approximate equivalency between the energies obtained from the two different experiments, the experimental results indicated that any comparison should be made with great care.We thank A. J. Lindfors and S. Pockrandt for the planar shock measurements. 相似文献