An analytical study on nonequilibrium dissociating gas flow behind a strong bow shockwave under rarefied conditions

In this paper, an explicitly analytical shock mapping relation is approximately deduced based on the theoretical modeling of the chemical nonequilibrium stagnation flow towards a slightly blunted nose. Based on the relation, the complex reacting stagnation flow problem can be discussed under the framework of the simplest normal shockwave flow. Therefore, a quantita- tively meaningful criterion for dissociation nonequilibrium flow, that is a specific Damk hler number Da d , is naturally intro- duced as the ratio of the mapping length of the stagnation streamline and the characteristic nonequilibrium scale. Da d is found to be dependent on the flow’s rarefaction criterion W r , that is a specific Knudsen number. Then, based on Da d , a normalized analytical formulation is obtained to quantitatively predict the actual degrees of dissociation at the outer edge of the stagnation point boundary layer (SPBL). At last, the direct simulation Monte Carlo (DSMC) method is employed to validate the analytical results, and the related flow mechanism is discussed. The present study not only shows nonequilibrium features of the flow problem, but also provides an indispensable basis for the following study on the nonequilibrium SPBL heat transfer.     

荧光光谱法研究除草剂扑草净和扑灭通与过氧化氢酶的相互作用

应用荧光光谱法研究了水溶液中三嗪类除草剂扑草净和扑灭通与过氧化氢酶分子间的相互作用。结果表明,除草剂对过氧化氢酶的荧光均有较强的猝灭作用,且静态猝灭是引起CAT荧光猝灭的主要原因。从荧光猝灭结果求出除草剂和CAT的结合常数及结合位点数。扑灭通:K=6.17×10~6 L·mol-1,n=1.45;扑草净:K=2.12×10~5 L·mol-1,n=1.19。并依据能量转移机制,求出了扑灭通、扑草净和CAT相互结合时,其给体-受体间距离r分别为0.140和0.155 nm。由此可见,扑灭通与CAT的结合作用要强于扑草净,并推测出除草剂与CAT的Tyr214发生结合作用。     

GaAs电阻的压电调制效应

木文提出了GaAs电阻的压电调制概念。用悬臂梁的例子,从理论和实验上研究了GaAs电阻的压电调制效应,并指出该效应与应力梯度有关。     

强激光场阈上电离理论

本文提出一种统一的阈上电离理论。根据该理论,可以定量描述较真实的原子阈上电离过程并能清楚地阐明实验观测的阈上电离现象。该现象可理解为前后相继的两个过程:(1)先从无场的初态吸收N个光子而到场缀末态的量子跃迁过程。(2)欲定量描述实验测量,还需考虑光电子逃离光场时与光场相互作用的“后作用效应”。该“后作用效应”是由非均匀激光场所形成的无质动力所引起的经典物理过程。 关键词：     

Pr0.2Yb0.8-xLaxBa2Cu3O7-δ体系的超导电性和磁性

本文研究了Pr_0.2Yb_0.8-xLa_xBa₂Cu₃O_7-δ体系的晶体结构,超导电性和磁性。结果表明,在Pr含量不变的条件下,超导转变温度随稀土离子半径增大而降低,当x≈0.65时,T_c=0;电子比热和费密能级上的态密度也随稀土离子半径增大而降低。并讨论了稀土离子半径与杂化的关系。 关键词：     

Simultaneous Space and Time Synchronization Using Shared Entangled Qubits

This paper generalizes the quantum clock synchronization protocol of Josza, et al., [Richard Jozsa, et al.,Phys. Rev. Lett. 85 (2000) 2010] to synchronize space and time simultaneously.     

A Novel Cu(II) Complex with 2,2′-Bipyridyl and L-Methioninate──Synthesis, Characterization, Molecular Structure and Stability

ＩｎｔｒｏｄｕｃｔｉｏｎＭａｎｙｅｎｚｙｍｅｓｒｅｑｕｉｒｅａｃｔｉｖａｔｉｏｎｂｙｍｅｔａｌｉｏｎｓａｎｄｔｈｕｓｔｈｅｙｏｆｔｅｎｉｎｖｏｌｖｅａｔｅｒｎａｒｙｅｎｚｙｍｅ/ｓｕｂｓｔｒａｔｅ/ｍｅｔａｌｉｏｎｃｏｍ ｐｌｅｘ .1Ｉｎｒｅｃｅｎｔｙｅａｒｓｃｏｎｓｉｄｅｒａｂｌｅａｔｔｅｎｔｉｏｎｈａｓｂｅｅｎｐａｉｄｔｏｔｈｅｔｅｒｎａｒｙｍｅｔａｌｃｏｍｐｌｅｘｅｓｉｎｖｏｌｖｉｎｇａｎａｒｏｍａｔｉｃａｍｉｎｅａｓｔｈｅｐｒｉｍａｒｙｌｉｇａｎｄａｎｄｖａｒｉｏｕｓｂｉｏｍｏｌｅｃｕｌｅｓ…     

论"一氧化氮的分子行为特性及其在生命科学中之重要意义"

基于分子聚集理论本文对一氧化氮(NO)的分子聚集行为特性作了研究,理论预计结果表明,一氧化氮具有特别强的分子聚集活性,也即它是一种很强的生物活性分子,实验研究工作已经证实,一氧化氮在人体的心血管系统,神经系统,以及免疫系统中起到很重要的生理功能作用.这就表明,本文所研究的内容对生命科学有其极重要的意义.     

Single Alternating Group Explicit（SAGE） Method for Electrochemical Finite Difference Digital Simulation

The four different schemes of Group Explicit Method (GEM):GER,GEL,SAGE and DAGE have been claimed to be unstable when employed for electrochemical digital simulations with large model diffusion coefficient DM.However,in this investigation,in spite of the conditional stability of GER and GEL,the SAGE scheme,which is a combination of GEL and GER,was found to be unconditionally stable when used for simulations of electrochemical reaction-diffusion and had a performance comparable with or even better than the fast Quasi Explicit Finite Difference Method(FQEFD) in some aspects.Corresponding differential equations of SAGE scheme for digital simulations of various electrochemical mechanisms with both uniform and exponentially expanded space units were established.The effectiveness of the SAGE method was further demonstrated by the simulations of an EC and a catalytic mechanism with very large homogeneous rate constants.     

强迫布鲁塞尔振子中混沌行为的控制

应用周期轨道确定技术找出了强迫布鲁塞尔振子的混沌吸引子中的不稳定周期轨道.应用Ott,Grebogi和Yorke的参数微调方法,使系统的运动状态由混沌变成所希望的周期运动.并且研究了这种控制的稳定性.最后提出了改进的控制方案,得到了更稳定、更好的结果. 关键词：