Analytical self-similar solutions of the Ginzburg-Landau equation with three-order dispersion effect

Based on the technique of the symmetry reduction, we find the asymptotic self-similarity analytical resolutions from the constant coefficient Ginzburg-Landau equation considering both influences of the thirdorder dispersion and gain dispersion on the evolution of pulses. We have obtained the self-similar pulse amplitude function, phase function, strict linear chirp function, and the effective temporal pulse width. Numerical simulations show qualitative agreement with these theoretical results.     

高阶色散效应常系数Ginzburg-Landau方程自相似脉冲演化的解析分析

采用自相似分析方法,基于常系数高阶色散的Ginzburg-Landau方程,通过分离变量法得出了高阶色散效应自相似脉冲演化的解析解,给出了自相似脉冲的振幅、相位、啁啾以及脉冲宽度的一般表达式.研究表明,在增益光纤的二阶正常色散区域,同时考虑高阶色散和增益色散双重效应影响下演化的自相似孤子脉冲仍然保持线性啁啾;振幅解析解的三阶色散效应显著.这与数值计算的结果非常一致. 关键词： 三阶色散 Ginzburg-Landau方程 自相似脉冲 二阶正常色散     

二维渗流最低水平开穿透的宽度

在二维渗流中,设rn是矩形[O,n]2的最低水平开穿透,令ξn=max｛y：（xy）∈rn｝．本文证明了在临界状态p＝pc时,存在常数0＜C1＜C2＜1,当n充分大时有存在,而在上临界状态p＞pc时,有存在］＝0.     

Microwave interrogation cavity for the rubidium space cold atom clock

The performance of space cold atom clocks(SCACs) should be improved thanks to the microgravity environment in space.The microwave interrogation cavity is a key element in a SCAC.In this paper,we develop a microwave interrogation cavity especially for the rubidium SCAC.The interrogation cavity has two microwave interaction zones with a single feedin source,which is located at the center of the cavity for symmetric coupling excitation and to ensure that the two interaction zones are in phase.The interrogation cavity has a measured resonance frequency of 6.835056471 GHz with a loaded quality factor of nearly 4200,which shows good agreement with simulation results.We measure the Rabi frequency of the clock transition of the rubidium atom in each microwave interaction zone,and subsequently demonstrate that the distributions of the magnetic field in the two interaction zones are the same and meet all requirements of the rubidium SCAC.     

二氧化铈的氯化反应机制研究

通过考察反应温度,时间及ＮＨ４Ｃｌ用量对ＣｅＯ２氯化的影响以及ＣｅＣｌ３．７Ｈ２Ｏ的热分解行为的研究,对ＣｅＯ２的氯化机制进行了探讨。结果表明,ＣｅＯ２在空气氛下采用ＮＨ４Ｃｌ氯化,在３００℃下其氯化率达到８０％左右,更高的温度反而不利于ＣｅＯ２的氯化,这主要是由于ＣｅＣｌ３．７Ｈ２Ｏ的热分解造成的。同时ＣｅＯ２的氯化并不是ＮＨ４Ｃｌ产生ＨＣｌ发生氰化,而是ＮＨ４Ｃｌ直接参与反应,生成中间化合物ＣｅＯＣｌ,然后转化为ＣｅＣｌ３．ＣｅＣｌ３．７Ｈ２Ｏ的热分解及热分析研究进一步说明了ＣｅＯＣｌ的存在,因此采用ＮＨ４Ｃｌ氯化ＣｅＯ２时,一方面应控制反应温度及反应时同,同时,过量的ＮＨ４Ｃｌ有利于ＣｅＣｌ３形成。     

镍钴助催化剂对环烷酸钼催化煤沥青悬浮床加氢反应活性的影响

合成了钼、镍、钴的五种分散型油溶性均相催化剂,选用高压釜反应器进行悬浮床加氢催化反应,控制反应条件在370℃、10 MPa氢压,反应时间4 h,考察环烷酸钼加入量、钼-镍、钼-钴双金属等比例对加氢反应的影响.通过反应结果的液体收率来衡量催化体系的煤沥青加氢催化效果.综合运用了元素分析、ICP-MS、透射电镜、X射线光电...     

RUIN PROBABILITY IN THE CONTINUOUS-TIME COMPOUND BINOMIAL MODEL WITH INVESTMENT

This article deals with the problem of minimizing ruin probability under optimal control for the continuous-time compound binomial model with investment.The jump mechanism in our article is different from that of Liu et al[4].Comparing with[4],the introduction of the investment,and hence,the additional Brownian motion term,makes the problem technically challenging.To overcome this technical difficulty,the theory of change of measure is used and an exponential martingale is obtained by virtue of the extended generator.The ruin probability is minimized through maximizing adjustment coefficient in the sense of Lundberg bounds.At the same time,the optimal investment strategy is obtained.     

MoO3表面分散作用对丝光沸石晶体结构的影响

将晶相MoO_3与丝光沸石充分研磨混合后,在一定高温下加热,MoO_3在丝光沸石上自发分散。当分散量较少时,丝光沸石的晶休结构无明显变化,加热时间的延长,MoO_3分散量增加。沸石结晶度降低;当分散量相同时,加热时间延长,沸石结晶度不变。结果表明,丝光沸石晶体结构的破坏,是由于分散的表面层钼与沸石骨架强烈相互作用的结果。MoO_3分散量越多,这种相互作用越强,沸石结晶度越低。     

用流动注射法研究巯基化合物—铈（IV）—氢化可的松的化学发光反应

采用流动注射法研究了巯基化合物－铈（Ⅳ）－氢化可的松（ＨＣＲｓ）体系的化学发光行为，对影响化学发光强度的诸因素进行试验和探讨，建立了流动注射化学发光法检测谷胱甘肽（ＧＳＨ），半胱氨酸（Ｃｙｓ）等含巯基化合物的新方法。检测ＧＳＨ和Ｃｙｓ和线性范围分别为２．０×１０＾－６￣１０．０×１０＾－５ｍｏｌ／Ｌ和１．０×１０＾－６ｍｏｌ／Ｌ￣１０．０×１０＾－５ｍｏｌ／Ｌ；检测限分别为２．０×１０＾－７ｍｏｌ