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光泵NH3分子远红外激光研究 总被引:6,自引:0,他引:6
运用量子系统的密度矩阵理论,采用迭代法计算了光泵NH3分子远红外超辐射和腔式激光的频谱特性和相应的最佳工作气压。理论计算表明相对于超辐射方式,光泵腔式NH3分子远红外激光具有宽带辐射以及纵向调谐特性,且总的输出光强在一定条件下得到提高,最佳工作气压也较低。在实验上对TEACO2-10R(8)和9R(16)泵浦的N 红外超辐射和腔式激光器产生的远红外辐射进行了测量。结果表明理论计算与实验结果相符。 相似文献
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小型光泵NH3分子远外激光器的模式竞争 总被引:1,自引:0,他引:1
通过求解四能级系统的半经典 密度矩阵方程迭代法计算了CO2-10R泵浦小型超辐射光泵NH3分子远红外激光器的P埃Q支跃迁输出光强的增量比。计算表明在超辐射小型NH3光泵远红外激光器中,V2:α→sP(5,4)和α→sQ(5,4)模式竞争结果,Q支跃迁占优势,使P支被抑制。理论计算与实验结果一致。 相似文献
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本文针对CO2减排,讨论了辐射致冷理论的相关问题。由于高层大气或外宇宙空间温度极低,可以此作为冷源,利用8~13μm的大气远红外窗口进行辐射散热,以降低能源消耗和CO2的排放,削弱温室效应。在量化分析过程中,大气中气体辐射特性与气溶胶粒子辐射特性对其散热效果起到决定性作用。本文对0.2~20μm波段的辐射通过大气层时,由于气溶胶粒子散射和吸收造成的衰减进行了米氏散射模型计算,验证了8~13μm大气远红外窗口在辐射致冷中的关键作用,并针对辐射致冷理论应用于CO2减排进行了相关理论性分析。 相似文献
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用区域分解算法结合蒙特卡罗法求坦克温度场和红外辐射出射度 总被引:3,自引:0,他引:3
本文将区域分解算法和蒙特卡罗法相结合,求坦克温度场和红外辐射出射度.采用蒙特卡罗法计算辐射传递系数,可以考虑界面的复杂辐射特性,如:镜反射、各向异性发射、各向异性反射等;可直接考虑界面的复杂几何特性,如:相互遮挡、太阳入射方向上的投影面积等.引入辐射传递系数,分离了计算的难点,使得在时间域(计算步骤)上能把整个问题分解为若干个子问题并行处理、在空间域(计算区域)上将坦克分解为若干个子区域,缩小计算规模,并可使用多个处理器并行计算;同时减轻了蒙特卡罗法编程的难度,缩短了计算时间. 相似文献
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在FEL实验中,电子束通过摇摆器,一方面由于周期性磁场作用,电子束轨迹要周期性的摆动,另一方面还要辐射同FEL辐射波长一致的自发辐射,该辐射谱反映电子束、摇摆器集成后的参数。在CAEP(Institute of China Academic Engineering Physics)远红外100 μm FEL实验中,自发辐射谱通过Ge∶Ga低温探头和远红外100 μm光栅谱仪测量。文章侧重从实际摇摆器磁场分析了远红外100 μm FEL的自发辐射谱。 相似文献
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开展了带楔块二维面阵脉冲超声相控阵辐射声场特性的研究。将安装在一定角度斜楔块上二维面阵相控阵换能器声场问题简化为液固界面情况进行讨论。以单阵元在液固平界面条件下的辐射声场为基础,推导了聚焦偏转法则,给出了带楔块二维面阵超声相控阵声场计算方法。以检测材料为钢板,安装在倾斜角为36°有机玻璃楔块上的频率为5 MHz、8×8二维面阵相控阵的辐射声场计算为例,分析了在不同偏转角和不同聚焦深度下检测材料中的辐射声场特性。计算结果表明该方法可有效的分析带楔块二维面阵超声相控阵声场特性并用于指导二维超声面阵角束探头的设计。 相似文献
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The ratio of amplitudes of waves generated by different interfaces in stratified inhomogeneous liquid is analytically studied. The amplitudes of waves generated by the second interface depend on the initial conditions and can be greater or less than the amplitudes of waves generated by the third interface. The amplitude ratio of the external and internal waves significantly depends on the ratio of liquid densities and layer thicknesses. Substantial effect of the initial conditions is manifested as a variation in the ratio of the amplitudes of external and internal waves and the amplitude ratio of waves generated by different interfaces. 相似文献
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Le Bas PY Ulrich TJ Anderson BE Guyer RA Johnson PA 《The Journal of the Acoustical Society of America》2011,130(4):EL258-EL263
A nonlinear scatterer is simulated in the body of a sample and demonstrates a technique to locate and define the elastic nature of the scatterer. Using the principle of time reversal, elastic wave energy is focused at the interface between blocks of optical grade glass and aluminum. Focusing of energy at the interface creates nonlinear wave scattering that can be detected on the sample perimeter with time-reversal mirror elements. The nonlinearly generated scattered signal is bandpass filtered about the nonlinearly generated components, time reversed and broadcast from the same mirror elements, and the signal is focused at the scattering location on the interface. 相似文献
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用光伏效应研究有机薄膜电致发光器件中的接触性质 总被引:2,自引:0,他引:2
首次发现了有机薄膜电致发光器件的光生伏特效应,通过对器件的光电流响应谱的详细研究,分析了不同结构的有机发光器件中的有机半导体之间,以及有机半导体与电极材料之间的半导体接触性质,发现有机发光材料Alq3,有机空穴传输材料daimine与金属铝电极之间形成阻挡接触,是电致发光器件发光和产生光电效应的根本原因;而双层器件中有机层Alq3与diamine之间的结是双层器件产生高发光效率的原因,正是这种结在双层器件中起了局限载流子和激子的作用,使发光亮度大为提高,结合分区掺杂实验结果,给出了较完善的能带模型. 相似文献
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An experimental study is performed to measure temperature variation of a carbide insert during metal cutting by means of fine thermocouples connected to a data acquisition system. A semiempiriad equation is developed based on transient conduction solutions combined with experimental data to predict temperature-time history in the cutting tool during operation. The governing parameters in the equation are derived, using AISI 1045 steel as the workpiece, to be the cutting speed, feed rate, and depth of cut at fixed rake and lead angles. Emphasis is placed on analyzing effects of the important factors on the cutting process, such as frictional heat generated at the tool-workpiece interface and wear of the tool. Dynamic behavior of the metal cutting process as predicted by the direct thermocouple measurement agreed with phenomenological observations reported in the existing literature. 相似文献
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A thermodynamic model of the formation of unbonded areas or bubbles generated at the interface of bonded silicon wafers in the temperature range of 200–800°C is presented. Within this model it is assumed that the desorption of hydrocarbon contamination at the silicon wafer surfaces leads to small hydrocarbon molecules which are mobile at the bonding interface. When the vapor pressure generated by these molecules overcomes the interface bonding strength, interface bubbles are nucleated. These bubbles grow by incorporating further hydrocarbon and also possible hydrogen molecules. The model semiquantitatively explains all the essential features of interface bubble formation observed experimentally. 相似文献
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Problems of acoustic wave propagation near the interface between media are discussed. The processes that occur at a liquid-gas interface are considered, and their characteristic features related to the effect of inhomogeneous waves are pointed out. The transmission factors of spherical and cylindrical waves incident on the aforementioned interface are calculated with allowance for the contribution of the inhomogeneous component. Experimental dependences of the transmission factor on frequency and source depth measured with respect to the interface are presented. It is shown that the lower the frequency generated by the source and the closer the source to the water-air interface, the higher the acoustic transparency of the interface. 相似文献
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采用平面冲击压缩方法产生密度和温度都均匀的氩等离子体,根据光谱辐射强度随时间的变化测量了氩等离子体在可见光区几个波长通道的辐射不透明度,等离子体温度在1.4—2.2eV范围,密度在0.0083—0.015gcm3之间.测量值和理论计算结果符合较好,说明平均原子模型可以较好地描述该热力学条件下氩等离子体的光子输运行为.基板表面的光反射率在确定辐射不透明度时是一个重要参数.采用简化的自洽方法求解基板表面的光反射率.结果表明,基板/氩气界面的光反射率R在0.4附近,与Erskine专门实验
关键词:
物态方程
不透明度
氩 相似文献