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This paper proposes a novel one-colour Xe-Kr laser induced collisional ionization system. Considering the level scheme of the system, it finds that the initial state of the reaction--the four 4f levels with even J of Xe-can be prepared through method of four-photon resonant excitation by dye laser with wavelength of -440 nm. Absorption of an additional photon (the transfer laser) of the same wavelength will complete the laser induced collisional ionization process. The resonance enhanced ionization spectrum of Xe by four laser photons at -440nm is measured through time-of-flight mass spectrometry, this aims at the preparation of the initial state of the system proposed. The Stark broadening of the measured spectrum is observed and consistent with the previous study. Analysis of the measured resonance ionization spectrum implies the feasibility of -440 nm four-photon resonant excitation of the initial 4f state of the Xe Kr system proposed in this paper, which prepares for a further experiment of laser induced collisional ionization.  相似文献   
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陈德应  张洪英  樊荣伟 《中国物理 B》2010,19(5):53402-053402
The four-level model of laser-induced collisional energy transfer(LICET) for the ion-ion collision system is established based on the time-dependent Schro¨dinger equation for the electron dynamics,through which the equations of motion of the probability amplitudes and cross section of the collision system are obtained.Numerical calculations are performed for the Ca+-Sr+ system,with the results showing that the peak of the LICET spectrum appears at a resonant frequency of the transfer laser.The magnitude of the obtained collision cross section is in the order of 10 16 cm2,and is comparable to that obtained in atomic systems,which indicates the validity of the established four-level model.  相似文献   
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设计一种基于STC89C51单片机的无线收发系统,本设计采用频率合成技术、FM调制技术及超外差解调技术,单片机对锁相环本振频率(发射43MHZ、接收53.7MHZ)锁定并通过液晶显示,本振频率在一定的范围内可调。将音频信号、咪头信号和数字英文字母信号作为调制信号,最后实现了音频、数字、英文字母等信号的重现。  相似文献   
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大鼠眼球的高场磁共振成像研究   总被引:1,自引:0,他引:1  
该文旨在研究微型磁共振(MRI)对大鼠眼球的成像效果和应用.通过对10只SD大鼠的20只眼球进行7.0 T MRI检查,应用常规T1WI和T2WI序列高分辨率扫描;观察MRI图像上大鼠眼球的结构,并比较MRI测量与组织学显微镜下测量视网膜厚度结果.磁共振扫描清楚地显示了所有受试大鼠眼球的主要结构,包括角膜、晶状体、玻璃体、视网膜、巩膜、虹膜、睫状体、视神经.球壁结构磁共振图像层次与组织学结构层次有良好对应性;磁共振视网膜厚度测量值与显微镜下视网膜厚度测量数据进行配对t检验,P0.05,二者无显著差异.由此得出的结论是小动物MRI可以对大鼠眼球细微解剖结构进行无创性的成像,为我们提供了一个研究大鼠眼科疾病模型的形态学及功能变化的手段.  相似文献   
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以现有的激光感生碰撞能量转移的四能级理论模型为基础,通过直接积分态振幅的运动方程,对弱场、强场两种情况下Ba-Sr系统的激光感生碰撞能量转移过程进行了数值计算,得到了两种情况下的激光感生碰撞跃迁概率和碰撞截面的谱线线型.在弱场情况下的数值计算结果与近似解析解的计算结果符合很好.对强场情况下的数值积分计算结果表明:激光感生碰撞作用随转换激光强度的增大而增强;强场时激光感生碰撞截面谱线的峰值位置明显偏离了共振频率并向紫端移动,且碰撞截面谱线的半宽度(即调谐范围)较之弱场明显变小. 关键词: 激光感生碰撞能量转移 碰撞截面 Ba-Sr系统 强场  相似文献   
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