Derivation of O(3) Electrodynamics from the Einstein–Sachs Theory of General Relativity

General relativity is reduced to O(3) electrodynamics by consideration of the irreducible representations of the Einstein group and through a particular choice of basis. The photon is shown always to possess a scalar curvature R, and so the origin of quantization is found in general relativity.     

用白炽灯作光源测量普朗克常量--第36届国际奥林匹克物理竞赛实验题分析

介绍了第36届国际奥林匹克物理竞赛“用白炽灯测量普朗克常量”实验,该题利用白炽灯作为辐射源并配合波长滤波器、减光板以及光敏电阻等装置,测量普朗克常量.文章对该实验进行了分析并给出解答.     

完善当期分配制度与建立延期分配制度有机结合——高校薪酬制度设计改革方向之探究

薪酬(compensation)是对雇员劳动和贡献的全部补偿，包括劳动的当期价值和长期价值的补偿．因此。薪酬包括当期分配和延期分配．当期分配旨在补偿已经付出的劳动。建立短期激励机制；延期分配旨在补偿风险损失，建立社会风险分担机制和长期激励机制．本文首先针对当期分配制度存在的缺陷，提出了完善当期分配制度的具体措施；其次，在论证建立延期分配制度之根据的基础上，积极探索建立适合高校自身特色的延期分配制度；最后，笔者认为，只有把当期分配和延期分配、短期激励和长期激励有机结合起来。高校才能吸引优秀人才、稳定优秀人才和培养出优秀人才．     

区间上单峰扩张自映射周期轨道的超旋转对

设f是区间I=[0,1]上的单峰扩张自映射, k ∈N,m≥2,λm,k是方程x(k-1)m(xm- 1)Q(x,m 1) (x(k-1)m-1)Q(x,m)=0在(1, ∞)上的唯一实根,其中Q(x,m)=(xm- 2xm-1 1).本文证明:若f的扩张常数λ≥λm,k,则f有超旋转对为(k,km 1)的周期轨道. 此外,还指出,当1<λ<λm,k时,在区间上存在单峰扩张自映射具有扩张常数λ却无超旋转对为(k,km 1)的周期轨道.     

用串联谐振微带元件测量射频介质的特性

介绍了利用微带电路来确定一组高性能、高频印刷电路板材料的介电常数和损耗角正切的方法，且给出了一组印刷电路板材料的特性测量值。     

A General Random Walk Model of Molecular Motor

A general random walk model framework is presented which can be used to statistically describe the internaldynamics and external mechanical movement of molecular motors along filament track. The motion of molecular motorin a periodic potential and a constant force is considered. We show that the molecular motor‘s movement becomesslower with the potential barrier increasing, but if the forceis increased, the molecular motor‘s movement becomesfaster. The relation between the effective rate constant and the potential barrier‘s height, and that between the effectiverate constant and the value of the force are discussed. Our results are consistent with the experiments and relevanttheoretical consideration, and can be used to explain some physiological phenomena.     

A Nd: YAG laser with a flat-top beam profile and constant divergence

An active resonator designed especially for Nd: YAG lasers is proposed. The expected performance of this resonator is the generation of a laser beam with a flat-topped distribution and a divergence invariant under the thermal lensing effect, such that it could be applied to surface treatment without special optical or mechanical elements. The beam quality and efficiency of such a resonator are presented and discussed in comparison with a parallel-plane resonator as adopted by most industrial Nd: YAG lasers.     

带电粒子在有心力场中运动时的两个守恒矢量

证明了带电粒子在有心力场中运动时有两个守恒矢量．其中之一存在于任意的有心力场中，另一个仅存在于与距离平方成反比的有心力场中．     

没有热效应的新型磁光测试装置

介绍了一种新型的磁光测试装置.根据法拉第磁致旋光效应,使用永磁片代替以往通电螺线圈产生磁场,不会产生热量,可以消除热效应对磁光介质费尔德常量的影响.通过实验测出这种磁场的分布特点,给出该装置的调节方法,并测出292 K温度下LaK2,LaK3,Tb20,Tb25,ZF6玻璃的费尔德常量.本实验为地磁成像技术提供了实验数据,并推动了该研究的进展.     

A New General Equation of the Polarographic Waves

A new general equation of the polarographic waves that improves the accuracy of the analysis has been obtained. The theoretical approach has been developed for Current Sampled DC Polarography or TAST Polarography, and can be used to study reversible, irreversible and quasi‐reversible waves. In order to facilitate the use of the new equation proposed, we have developed a computer program, TOP v1.0. This version works on Windows 32 bits systems (95/98/NT/Xp).