铸膜液溶剂体系的物理参数与BCA不对称膜的透气性

铸膜液的溶剂体系（溶剂和非溶剂）对不对称膜形态的形成有重要作用。为了探索溶剂和透气性间的关系，本文考虑到了制备ＢＣＡ梯度密度不对称膜的各种溶剂的一系列物理参数，得到了一些定性结果，并指出了更全面、明确、解释两者关系的研究方向。     

快电子与原子分子碰撞实验

 仅由原子分子体系本身的物理量决定.1935年,Bethe证明广义振子强度与光学振子强度之间有如下关系:f（E_j,q）=f⁰（E_j）+Aq²+Bq⁴+…,df（E,q）/dE=df⁰（E）/dE+Aq²+Bq⁴+…当q→0即高入射电子能量（T>>E）和0°散射角情况下,不管玻恩近似是否成立,都有:方程右边各物理量实验上都能测量.于是用快电子碰撞测量0°散射微分截面,即通过能量损失谱测量可得光学振子强度.     

电光晶体补偿位相测量微小位移及其应用

介绍一种应用电光晶体补偿位相测量微小位移的方法,着重分析其测量精度,并应用这种方法校正压电陶瓷的线性,精度优于1%波长。     

统一混沌系统的耦合同步

对线性耦合的两个统一混沌系统同步进行研究.基于线性时变连续系统的稳定性理论，得到初始值不同的两个统一混沌系统全局渐进同步的一种新的充分条件.另外，与已经提出的判定统一混沌系统同步的方法进行比较，发现这里得到的充分条件的约束关系少、缺少保守性，而且满足的耦合系数范围更广.将该方法应用于统一混沌系统，数值仿真表明了该法的有效性与可行性. 关键词： 统一混沌系统 耦合同步 线性时变连续系统     

基于空气焓差法空调制冷量的不确定度评定

介绍了空气焓差法测量空调制冷量的基本原理,并指出了目前空调制冷量的不确定度评定中存在的问题.考虑到风量、空调出风口焓值、喷嘴前焓湿量等中间变量存在明显的相关性,文中提出了采用直接测量量对空调制冷量求偏导来计算各分量的灵敏系数的方法.并且在明确各分量的标准不确定度的基础上,运用误差传递的原理,全面系统地分析了各分量对空调...     

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.     

巧用简谐运动的对称性解题

简谐运动的特点是具有往复性，相对平衡位置对称的两点，加速度、回复力、位移、均为等值反向，速度可能相同也可能等值反向，动能、势能一定相同．在实际问题中利用这些特点分析问题，往往会收到事半功倍的效果．     

不均匀垂直磁场中偏压AA堆积双层石墨中的朗道能谱

本文从量子力学的基本概念出发,在对称规范变换下,借助特殊函数方程理论,研究了不均匀磁场和垂直电场联合作用下AA堆积双层石墨的朗道能级结构.结果表明该体系中的朗道能级是高度简并的,特别是在狄拉克点处,而且该体系中偶然简并的零能朗道能级能够被垂直电场有效地调控.     

Supercontinuum generation in a standard single-mode fiber by a Q-switched Tm,Ho:YVO4 laser

Broadband mid-infrared(IR) supercontinuum laser is generated in standard single-mode fiber-28 directly pumped by a 2054 nm nanosecond Q-switched Tm,Ho:YVO4 laser. The average output powers of 0.53 W in the ~1.95–2.5 μm spectral band and 0.65 W in the ~1.97–2.45 μm spectral band are achieved at pulse rate frequencies of 7 and 10 kHz, and the corresponding optic-to-optic conversion efficiencies are 34.6% and 42.4% by considering the coupling efficiency. The output spectra have extremely high flatness in the range 2060–2400 and 2060–2360 nm with negligible intensity variation(2%), respectively. The output pulse shape is not split, and pulse width is reduced from 29 to ~15.4 ns. The beam quality factor M2 is 1.06, measured using traveling knife-edge method, and the laser beam spot is also monitored by an IR vidicon camera.