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61.
此文报道了H+、H+2和H+3离子通过碳膜后,在其中产生的各种微量产物的测量结果.讨论了离子与碳膜作用中的电荷交换过程.分析了这些微量产物的形成机理.实验证明在产物的形成中电荷交换过程起关键作用.研究了离子与碳膜作用中的团簇效应和尾流效应. 相似文献
62.
气溶胶前向散射大气能见度测量系统传递系数的标定及校准方法 总被引:4,自引:0,他引:4
分析了气溶胶的前向角散射特性,利用标准的大气透射仪标定前向散射大气能见度测量系统的传递系数。当系统结构发生变化时,传递系数也随之改变,为保证系统测量的准确性和简化系统传递系数的标定过程,提出了一种利用标准漫透射板校准系统传递系数的方法。该方法使用了两块具有相同透射系数的漫透射板,使气溶胶粒子团在前向半球上产生漫散射,此时探测器的测量值即为包含了仪器常数的定值。当系统结构改变时,这个测量值相对于原测量值的变化率作为比例系数代入系统传递系数的计算,实现校准。 相似文献
63.
在常利率环境下,研究当索赔时间间隔为Erlang(2)分布且保费收取为两步保费的风险模型,推导出该模型Gerber-Shiu罚金折现期望函数所满足的微积分方程. 相似文献
64.
Two New Compounds from Lindera chunii Merr. 总被引:1,自引:0,他引:1
Mian ZHANG Chao Feng ZHANG Qi Shi SUN Zheng Tao WANG 《中国化学快报》2006,17(10):1325-1327
The root of Lindera chunii Merr. is a noble traditional Chinese medicine and frequently used as a substitute for L. aggregata to cure the chronic disease of rheumatoid arthritis1. In our previous paper, we have reported some components from the roots of L… 相似文献
65.
The bipolar phase-shift-keying (BPSK) optical orthogonal codes (OOCs) are inserted into the optical packet format of bit-serial label. The ultra-fast separation of the label and payload is performed through the auto-correlation pulses indicating the time position at which the optical switch changes the state.The insertion of the new label can also be realized by detecting the auto-correlation pulse at the line rate. Especially, the scheme can be adapted to the asynchronous separation and insertion and realize the variable-length packet switching. The results of simulation verify the feasibility of the scheme. 相似文献
66.
本文提出一个用Rankine涡模型模拟对称和非对称台风的方法·考虑到台风和Rankine涡之间物理性质的相似性,从定性上分析了这一方法的可行性·参照Yancy台风的观测数据,给出模拟某一时刻台风内部结构的Rankine涡模型的涡参数·这一结果是进一步用等值线动力学方法研究台风运动的基础 相似文献
67.
Song Guanbin Yu Weiqun Liu Baoan Long Mian Wu Zezhi Wang Bochu 《Colloids and surfaces. B, Biointerfaces》2002,24(3-4):327-332
Having made use of the micropipette aspiration technique, we here investigated the viscoelastic properties of hepatocellular carcinoma (HTC) cells from the view of cell cycle. The synchronous G1 and S phase cells were achieved through thymine-2-desoryriboside and colchicine sequential blockage method and double thymine-2-desoryriboside blockage method, respectively. The synchronization results detected with flow cytometer showed that it could meet the requirements of the experiments nicely. Experimental results were analyzed with a standard linear solid viscoelastic model, in which an elastic element, K1, is in parallel with a Maxwell element composed of another elastic element, K2, in series with a viscous element, μ. The results indicated that high K1, K2 values and low μ value was the general characteristics of the cells; G1 phase cells had higher K1 values and low μ value than S phase cells, which endowed G1 phase cells with higher elasticity and faster passive deformability than S phase cells. The results maybe also reflected the difference of cytoskeleton between G1 and S phase cells, and suggested that G1 phase cells were more suitable for surviving and metastasis in blood circulation than S phase cells. 相似文献
68.
MianZhou YiFu WenXu XiXu 《高分子科学》2005,(1):17-21
The mechanical properties of ozonized high density polyethylene (HDPE) blended with sericite-tridymite-cristobalite (STC) were studied in this paper. The experimental results show that some oxygen containing polar groups are introduced on the molecular chain of HDPE through ozonization, the compatibility between HDPE and STC is thus improved, the mechanical properties of the blend are markedly enhanced. Compared with untreated HDPE/STC (60/40) blend, the yield strength and notched impact strength of ozonized HDPE/STC (60/40) blend are increased from 27.0MPa to 29.5MPa and from 2.8kJ/m^2 to 13.3kJ/m^2, respectively, the notched impact strength is close to that of HDPE (13.6kJ/m^2),the yield strength is in excess of 3.9MPa of that of HDPE. The yield strength and notched impact strength will be further increased to 30.7MPa and 32.4kJ/m^2 in case the ozonized HDPE is blended with STC pretreated with silane coupling agent. 相似文献
69.
Wen‐Xiu Ni Mian Li Ji Zheng Shun‐Ze Zhan Yu‐Min Qiu Seik Weng Ng Dan Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(50):13720-13720
70.
Yun‐Heng Shen Yong‐Qing Su Jun‐Mian Tian Sheng Lin Hui‐Liang Li Jian Tang Wei‐Dong Zhang 《Helvetica chimica acta》2010,93(12):2393-2396
A novel alkaloid with a unique indolo‐[1,7]naphthyridine nucleus, incargranine B, was isolated from the whole plant of Incarvillea mairei var. grandiflora (Wehrh.) Grierson . Its structure was determined by means of spectroscopic methods. 相似文献