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941.
942.
李凯潘清肖德鑫王汉斌 《强激光与粒子束》2013,(B05):161-163
采用氧过量YOYO激活工艺对经高温清洁的砷化镓(GaAs)晶片进行激活,测量其量子效率和在激光及背景光照射下的使用寿命,得到了4.66%的量子效率;在电子枪中的实验获得了平均流强大于1mA的束流。分析了真空度、高温清洁温度、铯氧激活工艺等因素对GaAs光阴极初始量子效率和使用寿命的影响。 相似文献
943.
We investigate the applicability of the independent atom model (IAM) to elastic electron scattering from complex polyatomic molecules, namely C4H10 and C6H6, in the energy range 100-1000eV. The cross sections of the elastic electron scattering are calculated by employing the IAM together with the relativistic partial waves. The incorporation of both the modified absorption potential and the extended structural factor in the IAM makes the elastic differential cross sections and momentum transfer cross sections have a good agreement with the available experimental data. The present simple model seems to be insensitive to the complexity of the target molecules so that the proposed procedure can be quite useful for calculation of electron scattering from bio-molecules. 相似文献
944.
Fifth-order phase-sensitive detection of ultrafast polarization beats in cascade four-level system 下载免费PDF全文
We study the colour-locked twin-noisy-field correlation effects in the fifth-order nonlinear susceptibility of ultrafast polarization beats in a cascade four-level system. More importantly, the fifth-order phase-sensitive heterodyne detection of ultrafast polarization beats has been exploited. The fifth-order nonlinear optical response can be controlled and modified through the colour-locked correlation of twin noisy fields. Thus, this method with the phase dispersion information is a good way to measure the real and imaginary parts of the fifth-order nonlinear susceptibility. 相似文献
945.
946.
Some experimental techniques and theoretical analysis on unbound nuclei structure study are briefly introduced in this article. The unbound nuclei structure investigation can inspect the reliability of theoretical calculation, and is also important to extend the modern nuclear structure model to exotic nuclear regions. With the recent development of radioactive Ion Beam (RIB) facility and some new experimental methods, the structure of unbound nuclei near drip line can be studied in experiment. 相似文献
947.
食用花卉中可溶性锌无机态、有机态分离与分析 总被引:1,自引:1,他引:1
采用0.45 μm微孔滤膜、XAD-2大孔网状树脂将3种常见食用花卉菊花、金银花、芙蓉花的水煎液中锌的形态分为无机态与有机态,得出了分离无机态与有机态的最佳操作条件:上柱液pH 3.0,上柱液流速5.0 mL·min-1,无机淋洗液流速为5.0 mL·min-1,淋洗液为1.0% HNO3。Zn有机态洗脱剂丙酮的流速水平为6.0 mL·min-1,丙酮用量30 mL。利用原子吸收分光光度计测定了花卉中锌的总量、可溶有机态和无机态的含量。结果表明花卉中Zn的总量与形态分布有一定相关性,可溶性Zn无机态分布为64%~68%,有机态分布为32%~36%;另外,花卉品种不同,对补充无机态Zn的效果不同,但对补充有机态Zn效果相近,这为食用花卉作为第三代功能食品基料的开发提供了一定的理论依据。 相似文献
948.
Synthesis and Field Emission of ZnO Nanostructures on CuO Catalyzed Porous Silicon Substrate 下载免费PDF全文
Mass production of ZnO nanobelts and hexagonal nanorods has been successfully synthesized on CuO catalyzed porous silicon (PS) using a simple vapour-solid (VS) growth method. A comparison of their morphologies is investigated by scanning electron microscopy (SEM). The transmission electron microscopy (TEM) confirms that ZnO nanobelts and nanorods are single crystalline with the growth direction of (0110) and (0001), respectively. Field emission tests indicate that the ZnO nanostructures on porous silicon have low turn-on field of about 3.6 V/μm (at 1.0μA/cm^2) and the threshold field of about 8.3 V/μm (at 1.0mA/cm^2), high emission site density (ESD) of approximately 104 cm^-2. 相似文献
949.
介绍适用于机敏材料与结构状态监测和损伤估计的三种简单的强度调制型准分布式光纤传感阵列,并比较其各自的优缺点 。 相似文献
950.
Investigation on the deformation of Ne and Mg isotope chains within relativistic mean-field model 下载免费PDF全文
Ne and Mg isotope chains are investigated based on constrained calculations in the framework of a deformed relativistic mean-field (RMF) model with the NL075 parameter set. The calculated quadrupole deformation and binding energy are compared with other theoretical results as well as the available experimental data. It shows that the calculated deformations of Ne and Mg with the NL075 are more accurate than those obtained with the NL-SH. It is predicted that ^19,29,32Ne and ^20,31Mg maybe have a triaxial deformation and ^25-28Ne and ^27-30Mg exhibit a shape coexistence probably. The closure effect of neutron number N=8 for ^20Mg is predicted to be very weak. 相似文献