The second harmonic resonance for the shallow water surface-wave in a rectangular trough

By using the perturbation method of multiple scales, this paper deals with the phenomenon of the second harmonic resonance for shallow water surface-wave in a rectangular trough. The results show that the envelope of the wave only depends on slow-variables of time. Eqs. of wave envelope are strictly solved and the results are discussed.Project Supported by the Natural Science Fund of China.     

尼可刹米与牛血清白蛋白相互作用及共存金属离子的影响

在优化的实验条件下,运用光谱法研究牛血清白蛋白（BSA）与尼可刹米（NI）的相互作用及共存金属离子的影响。研究表明:NI对BSA的荧光有猝灭作用,属于动态猝灭。BSA能运输NI,是一个自发过程,其作用力类型主要为疏水作用力。BSA的亚螺旋域ⅡA是主要结合位置,离酪氨酸残基更近,无药物协同作用。NI对BSA构象产生影响。Mg²⁺、Cu²⁺对PDS与BSA结合产生竞争作用,增强药效。Mn²⁺、Cr³⁺和Co²⁺对PDS与BSA结合产生促进作用,延长药效时间。该实验对揭示药物动力学问题及新药的研发提供了理论依据。 更多还原     

Effect of passive plates on vertical instability in the EAST tokamak

The effect of passive plates on vertical displacement control in the EAST tokamak is investigated by open loop experiments and numerical simulations based on a rigid displacement model.The experiments and simulations indicate that the vertical instability growth rate is reduced by a factor of about 2 in the presence of the passive plates,where the adjacent segments are not connected to each other.The simulations also show that the vertical instability growth rate is reduced by a factor of about 10 if all adjacent segments on each passive plate loop are connected to each other.The operational window is greatly enlarged with the passive plates.     

有机电光晶体4-(4-二甲基氨基苯乙烯基)甲基吡啶对甲基苯磺酸盐的太赫兹光谱研究

采用色散校正的密度泛函理论(dispersion-corrected density functional theory,DFT-D2)对有机电光晶体4-(4-二甲基氨基苯乙烯基)甲基吡啶对甲基苯磺酸盐(4-N,N-dimethylamino-4′-N′-methyl-stilbazolium tosylate,DAST)进行结构优化和太赫兹光谱计算,通过逐步提高精度进行几何优化的方法寻找DAST收敛的基态稳定结构,获得与DAST初始结构相一致的基态稳定结构.在此结构的基础上,在0—4 THz范围的太赫兹计算光谱与实验测量结果一致,说明采用DFT-D2进行优化的合理性.重要的是,首次通过计算的太赫兹光谱对DAST在0—4 THz范围的太赫兹吸收峰的振动模式进行了详细归属.结果表明:1.12 THz处的振动是DAST阴阳离子的光学声子模式,1.46 THz和1.54 THz两处的振动主要与磺酸盐有关,而2.63 THz和3.16 THz两处的振动则分别源于阳离子的扭转振动和阴离子的转动.该结果不仅很好地说明了阴阳离子分别在太赫兹响应中的贡献,而且为今后通过取代阴阳离子基团获取具有更高二阶非线性效应的DAST衍生物的新合成提供了重要的参考和指导.本文结果说明密度泛函理论在太赫兹光子学上的重要应用,对探究有机电光晶体的太赫兹响应物理原理、性能控制等具有重要的指导价值.     

新一代光谱仪器：Leeman ICP／Echelle

引言自十九世纪中叶火焰光度计面世后,发射光谱便成为一种被普遍采用的分析方法。二十世纪四十年代出现的电弧/火花光电直读光谱仪,提高了分析速度,直至二十世纪七十年代电感耦合等离子体(ICP)激发光源,以其稳定性好、激发温度高,分析浓度范围宽和化学干扰少等优点,开拓了发射光谱分析应用的领域。目前,等离子发射光谱     

充满流体的圆形管道上应力波包络孤子

本文应用多重尺度约化微扰方法研究了充满流体的圆形弹性管壁上应力波的弱非线性调制问题。得到单模情形下波振幅所满足的非线性Schrodinger方程及其包络孤子解。     

Coupled Optical Solitons for Pulse Propagation in Multi-Level Media

We investigate the shape-preserving propagation of N optical pulses in an （N ＋ 1）-level medium. We solve Maxwell-Schroedinger equations exactly and provide several types of explicit coupled soliton solutions, which are temporally amplitude- and group-velocity-matched multi-mode slow-optical pulses of the system.     

非线性传输线中的包络孤波

本文应用多重尺度微扰方法研究了双线或同轴传输线中传播波的非线性调制,导出了波振幅所满足的非线性schrodinger方程,并给出了包络孤波解,这对于电力传输问题的研究是有帮助的。