NEPCⅡ新电子枪热结构分析与测试

北京正负电子对撞机重大改造工程(BEPCⅡ)要求其直线注入器提供更高的能量和流强, 为此必须设计大电流和小发射度的新电子枪, 以提高正电子的产额. 利用ANSYS对BEPCⅡ新电子枪的温度场分布及结构的热变形进行了模拟分析. 对于电子枪复杂的内部结构形态以及能量转换方式, 分析了传导传热方式对温度场的影响. 在此基础上进行了温度场与结构变形的耦合分析, 利用EGUN对电子枪形变前后束流光学特性进行模拟分析, 并对模拟结果与试验 测试结果进行了分析比较.     

多周期公用工程系统运行的模型,优化方法与应用

针对多周期公用工程系统的运行优化问题，考虑了设备的启停费用的情况下。建立了混合整数非线性规划模型并证明了最优解的存在性。针对该运行优化问题本将其分解成若干子问题，然后利用改进的Hooke-Jeeves优化算法求解每个子问题。应用于具体实例，其数值结果与其它方法得到的相比。运行时间短，且更适合多周期公用工程问题的求解。     

常规投资项目的外部收益率研究

揭示了常规投资项目外部收益率的实质 ,明确了常规投资项目外部收益率的缺陷 .研究表明 ,在实际工作中 ,不宜用外部收益率替代内部收益率进行常规投资项目的经济性分析评价     

Photo-induced effect in the layered perovskite manganite La<Subscript>1.2</Subscript>Sr<Subscript>1.8</Subscript>Mn<Subscript>1.8</Subscript>Co<Subscript>0.2</Subscript>O<Subscript>7</Subscript>

It is helpful to study the photo-induced effect in the perovskite manganites not only for elucidating the mechanism of colossal magnetoresistance (CMR) effect but also for potential applications in technology. The laser-induced effect in the Co doping layered perovskite manganites La_1.2Sr_1.8Mn_1.8Co_0.2O₇, is studied in this paper and the obtained results are also compared with that gained in the Nd-doping manganites with cubic perovskite structure.     

Tokamak Experiment and Tokamak Engineering——Development of the Plasma Diagnostics on HL-2A Tokamak

The main mission the HL-2A tokamak is of the experiments on to explore the divertor physics and to investigate the plasma confinement, transport and instabilities with high power auxiliary heating and advanced fuelling, it is necessary to develop more new diagnostics and increase the spatial and temporal resolutions of the measurements for exist system. Up to now, about 30 diagnostic systems have been moved from HL-1M to HL-2A tokamak. Other 10 diagnostic systems are being designed and installed on the device. In developed in last 2 years, will be presented.     

Time-Resolved Femtosecond Degenerate Four-Wave Mixing in LiNbO3：Fe,Mg Crystal

Forward degenerate four-wave mixing （DFWM） processes are investigated with a femtosecond pulsed laser in lithium niobate crystal doubly-doped with magnesium and iron （LiNbO3：Fe, Mg）. The pulse energy dependence reveals a pure third-order nonlinear response, and the third-order nonlinear susceptibility x^（3） in the material is evaluated to be 4.96 × 10^-13 esu. The time-resolved DFWM process shows a response time of x^（3） shorter than 100fs, which is due to the nonresonant electronic nonlinearities. Our results indicate that LiNbO3 crystals have potentials for ultrafast real-time optical processing systems, which require a large and fast x^（3） optical nonlinearity.     

J/ψ Dissociation in QGP via Multi-gluon Absorption

We propose that the suppression of J/ψ production in relativistic heavy ion collisions may be explained by that J/ψ dissociates via absorbing multi-gluons in the environment of quark-gluon-plasma (QGP) where abundance of gluons is expected.     

一些包含Lucas数的恒等式

利用第一类Chebyshev多项式的性质以及其与Lucas数的关系得到了关于Lucas数立方的一些恒等式.     

关于"惯性秤"实验的思考

介绍了惯性秤的基本原理，分析了惯性秤不同放置情况的测量结果。     

邻苯二甲酸酐与季戊四醇缩聚反应模型的统计处理

首次用统计方法对邻苯二甲酸酐与季戊四醇缩聚反应进了严格处理，获得了缩聚物的数量分布和重量分布函数，数均和重均分子量的表达式。同时还用环形处理法获得了邻苯二甲酸酐与季戊四醇缩聚反应的凝胶化条件。