盐生盐杆菌灭活原生质体融合的研究

通过双亲灭活方法将二株具不同遗传学特性的盐生盐杆菌Ｊ７（含质粒，不产紫膜）和Ｒ１（产紫膜，不含质粒）进行原生质体融合试验．结果表明，在以３０％ＰＥＧ６００为助融剂，加２５ｍｍｏｌ·Ｌ－１ＥＤＴＡ条件下，４０℃保温１ｍｉｎ，获得融合率为０．７６×１０－５的融合子．这些融合子具有双亲菌株的某些特征，其中２２％的融合子既含有质粒又产紫膜，这些融合子对于进一步研究质粒与紫膜的关系，以及筛选高产紫膜的优良菌株，均有十分重要的价值．     

罗素悖论与弗协调逻辑

本文以胡世华教授建立的自然推理系统为基础,构造了一个弗协调逻辑H.在以H为逻辑的弗协调集合论S_H中,罗素(B.Russell)命题是可证的.     

Si含量对高锰硅化合物相组成及热电性能的影响研究

采用高频感应熔融、退火结合放电等离子烧结方法制备高锰硅(HMS)化合物MnSi1.70+x(x=0,0.05,0.1,0.15),系统研究了Si含量变化对材料相组成、微结构和热电性能的影响规律.结果表明,当x0.1时,样品由HMS和贫Si的MnSi金属相两相组成,随着Si含量x的增加,MnSi相相对含量减小;当x=0.1时,所得样品为单相HMS化合物;当x0.1时,样品由HMS和过量Si两相组成.随着x的增加,由于样品中高电导的金属相MnSi含量逐渐减少,样品的电导率逐渐下降,而Seebeck系数随之增加.室温下样品载流子浓度和有效质量随x增大逐渐减小,而迁移率逐渐增加.MnSi和Si杂相与HMS相比均为高热导相,因此当x=0.1时,由于样品为单相HMS,从而表现出最低热导率和最高ZT值.MnSi1.80样品在800K时热导率最小值达到2.25W·m-1K-1,并在850K处获得最大ZT值(0.45).     

Beam emittance investigation in high brightness injector using different driver laser profiles

Beam emittance plays an important role in any accelerator, and it is a main parameter to judge the performance of an accelerator. Emittance optimization is an indispensable part in conditioning and operation of the facility. For a laser-driven high brightness injector, different time structure of the laser pulse has different effects on transverse emittance. In order to compare Gaussian and flat-top laser pulse, systematic simulations of 500 pC have been done. From the simulation results, one can see that flat-top pulse laser will yield smaller minimal transverse beam size and transverse beam emittance than Gaussian pulse laser.     

A new type of Lie symmetrical non-Noether conserved quantity for nonholonomic systems

For a nonholonomic system, a new type of Lie symmetrical non-Noether conserved quantity is given under general infinitesimal transformations of groups in which time is variable. On the basis of the invariance theory of differential equations of motion under infinitesimal transformations for t and q_s, we construct the Lie symmetrical determining equations, the constrained restriction equations and the additional restriction equations of the system. And a new type of Lie symmetrical non-Noether conserved quantity is directly obtained from the Lie symmetry of the system, which only depends on the variables t, q_s and \dot{q}_s. A series of deductions are inferred for a holonomic nonconservative system, Lagrangian system and other dynamical systems in the case of vanishing of time variation. An example is given to illustrate the application of the results.     

两种测试高温超导薄膜微波表面电阻方法的讨论

介绍两种工作在12GHz附近的高温超导薄膜微波表面电阻Rs测试系统,并分析各自的特点.同时简介电子科技大学在提高Rs测试精度上所作的一些改进.     

Pose estimation for UAV aerial refueling with serious turbulences based on extended Kalman filter

In recent years, many pose estimation algorithms were developed, and have been successfully applied to solve unmanned aerial vehicle (UAV) aerial refueling pose estimation problems. This paper mainly focuses on solving this problem under serious turbulences circumstance. The extended Kalman filter is a set of mathematical equations to estimate the state of a process, which is able to support estimations of past, present, and even future states. In reference to previous papers and some simulations, we build up the noise models of refueling boom and atmospheric turbulence. Then, an extend Kalman filter is adopted to solve the pose estimation problem in UAV aerial refueling with serious turbulences. The experimental results demonstrate the feasibility and effectiveness of our proposed approach.     

Experimental characterization and correction of non-equivalence of Solar Irradiance Absolute Radiometer

We experimentally evaluate and correct the non-equivalence between electrical and radiative heating of solar irradiance absolute radiometer to compensate the systematic error of radiant power measurement at ambient pressure. A relative difference of the order of 0.08%-0.27% between electrical and radiative heating sensitivities is shown, and the resulting non-equivalence correction factor is calculated. The radiant power measurement equation is modified using the non-equivalence correction factor, a systematic deviation of 0.19% of radiant power measurement is hence eliminated.     

W波段回旋行波管输入输出段的改进设计

在回旋行波放大器的设计中,输入输出段的性能直接影响到整管输出功率、效率及增益。设计了一种采用渐变过渡段的输入耦合器来减少电子注在前端的截获,而且略微地提高了耦合特性,有效带宽达到4.06 GHz。采用二级切比雪夫渐变波导作为输出结构的耦合输出段,从仿真结果得到,在整个工作频段内,该结构中TE01工作模式的反射低于-20 dB,TE01模向杂模TE02和TE03的耦合分别在-20 dB和-30 dB以下。