真空条件下LiCl溶液蒸发量随浓度变化规律研究

除湿溶液再生是除湿空调系统的核心过程,为了提高除湿溶液再生效率,以蒸发量作为评价标准,在不同的真空度下对不同浓度LiCl溶液进行再生。对不同再生条件下,溶液的再生情况进行数学模拟及实验研究,并将模拟结果与实验结果进行对比分析,结果表明,实验结果同模拟结果具有相同的变化趋势。在6 kPa和8 kPa的压强下,LiCl溶液的蒸发量随浓度的增大先上升后下降,而在1 kPa的压强下,LiCl溶液的蒸发量随浓度的增大呈现出先下降再升高接着又下降的趋势。     

激光惯性约束聚变中光学汤姆逊散射研究进展

当前,激光惯性约束聚变在越来越接近点火的极端能量密度条件下,实验与模拟的偏离逐渐增大,一个关键原因是缺乏对黑腔等离子体状态及其影响黑腔能量学和内爆对称性的细致研究和判断。光学汤姆逊散射主动式、诊断精确、参数完备的优点,使之成为激光惯性约束聚变黑腔等离子体状态参数精密诊断的标准方法。中国面向激光惯性约束聚变研究的光学汤姆逊散射实验技术的发展与神光系列激光装置的建设和在其上开展的物理实验紧密相关。近年来,四倍频汤姆逊散射实验技术在神光III原型和100 kJ激光装置上相继建立,部分实验结果不仅加深了对激光惯性约束聚变靶物理的认识,还反映了实验条件对汤姆逊散射诊断的影响,促进了实验技术的精密化发展。在未来,还需要进一步发展多支路汤姆逊散射、五倍频汤姆逊散射和超热相干汤姆逊散射等新技术,面向点火黑腔条件,大幅提升激光等离子体状态参数的诊断精度,开展新物理机制的探索和研究,在激光惯性约束聚变和其他高能量密度物理科学领域发挥更重要的作用。     

Effects of doping on the surface energies of nanocrystals and evidence from studies at high pressure

Zn_1−XMn_XS (X=0.85% and 1.26%) nanoparticles have been synthesized using a specially designed equipment and we have studied the influence of doping Mn²⁺ on the surface energy of ZnS. The high pressure behaviors of ZnS nanocrystals with different dopant contents have been investigated using angle-dispersive synchrotron X-ray powder diffraction up to 45.1 GPa. Theoretical calculations show that doping with Mn²⁺ increases the surface energy of the nanocrystals. The theoretical result has been further corroborated by our experimental observation of an increase in the phase transition pressure of Mn²⁺ doped ZnS nanocrystals in diamond-anvil-cell studies.     

Thermal conductance in quantum wire with two obstacles

Based on the scattering-matrix method, the influence of obstacles on the thermal conductance in quantum wire was investigated. Three types of obstacles are employed in our calculation. We present a detailed study of the thermal conductance as a function of distance between two obstacles and temperature. The results show that there is qualitative difference in the dependence of the thermal conductance versus width between two obstacles for different temperatures. We also find that the calculated thermal conductance increases with the width W of quantum wire in all cases.     

Signaling-based path-segment protection in mesh optical networks

Path protections have become increasingly important for current mesh optical networks because fast restorations in generalized multiprotocol label switching(GMPLS) networks are uncertain.However,setting up additional disjoint paths to protect connections leads to more path setup blocking and signaling collisions.We analyze signaling collisions,path blocking and blocking probability,as well as calculate node-to-node blocking probabilities.A signaling-based path-segment protection(PSP) is proposed,which integrates segment protections and path protections as well as enhances the performance of path protections and ring protections.The setup of PSP connections causes less blocking probability than the setup of path protection connections in the simulations.     

干涉高斯光诱导的表面等离子激元驻波场的分析

考虑到实际入射光强的空间分布不均匀,基于Kretschmann模型并采用角谱方法分析模拟了两束高斯光干涉诱导表面等离子激元(SPP)驻波场。与理想平面波不同,高斯光诱导的SPP干涉条纹幅值大小不等,分布复杂,这表明光强空间非均匀程度会严重地影响到曝光深度的分布。还分析了金属薄膜的厚度、损耗以及光刻胶的介电常数对SPP驻波场的影响,并得出不恰当的金属板厚和细微损耗都会极大削弱SPP驻波场,而如果光刻胶的介电常数过大则有可能产生不了表面等离子体共振的结论。     

Z箍缩驱动器与丝阵负载耦合特性研究

以丝阵内爆零维模型为基础,采用Pspice模拟行为建模方法,建立了丝阵内爆动态电感与Z箍缩驱动器耦合的全电路模型,实现驱动器放电过程与丝阵内爆过程的自洽求解,并研究了丝阵参数、电路参数对内爆过程的影响.结果表明:丝阵负载与驱动器存在强耦合关系,丝阵参数、电路参数对丝阵峰值箍缩电流、内爆时间、内爆动能影响很大;在驱动器参数不变,内爆时间不超过电路固有放电周期1/4的前提下,峰值箍缩电流、内爆时间、内爆动能随丝阵质量的增加而增大,内爆时间随丝阵初始半径的增加而增大;在丝阵参数不变时,随着驱动器等效电容的增大,内爆时间减小,丝阵内爆动能增大,但驱动器储能转化为内爆动能的效率却先增大后减小.对于特定的驱动器,优化的丝阵参数应使内爆过程充分利用驱动器固有放电周期的上升沿,使丝阵快速收缩的时间起点接近电路固有放电周期的四分之一,以获得最大的动能效率. 关键词： Z箍缩驱动器 零维内爆模型 模拟行为建模 耦合特性     

基于计算机视觉的蜂窝陶瓷在线检测系统研究

研发了一种基于计算机视觉的蜂窝陶瓷智能在线检测系统;设计了系统的体系结构,4台高速摄像机在线获取蜂窝陶瓷图像,研究了改进型加权中值滤波处理,论述了基于Fisher评价函数的图像阈值分割算法;最后进行亚像素测量,判断产品尺寸是否在允许范围内,实验验证了系统的有效性和检测算法的可行性,可以很好地代替人工检测。     

Long-period-grating-assisted optical add-drop filter based on mismatched twin-core photosensitive-cladding fiber

A noninterferometric optical fiber add-drop channel filter based on a mismatched twin-core photosensitive-cladding fiber and long-period fiber grating is demonstrated. With assistance from the fiber grating, co-directional spectrally selective cross coupling between the two cores can be realized with an efficiency of 90%.     

Nonlinear optical properties of nanometer-size silver composite azobenzene containing polydiacetylene film

Diacetylene monomer containing p-nitrophenyl azobenzene moiety (NADA) was synthesized. Silver nanoparticles with different concentrations were adulterated in the above polymerized NADA (PNADA) films and the third-order nonlinear optical properties were investigated in detail. UV–vis spectra and transmission electron microscopy were used to confirm the formation of PNADA/Ag nanocomposite films. The silver nanoparticles (average size of 10 nm) were well dispersed in the polymer films. The value of the nonlinear refractive index n ₂ for PNADA films (8.48×10⁻¹⁵ cm²/W) was much higher than that of pure polydiacetylene films. Further, the introduction of silver nanoparticles into the PNADA polymer films led to the further enhancement of nonlinear optical properties. The maximum value of n ₂ for PNADA/Ag nanocomposite films could be 11.6×10⁻¹⁵ cm²/W. This enhancement should be ascribed to the surface plasmon resonance of silver nanoparticles.