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981.
The effects of vacuum-induced coherence (VIC) on the properties of the absorption and gain of the probe field in an equispaced three-level ladder atomic system are investigated. It is found that lasing without inversion (LWI) is remarkably enhanced due to the effect of VIC in the case of the small incoherent pump rate. 相似文献
982.
用正交光路全息干涉CT技术重建电弧等离子体三维温度场 总被引:3,自引:3,他引:0
本文利用正交光路全息干涉技术和计算机有限角层析算法,借助电弧等离子体物理方程,对非对称电弧等离子体三维温度场的诊断进行了研究. 相似文献
983.
弹簧的弹力是由于弹簧的形变产生的,要它恢复形变或产生形变就需要时间,于是有的学生认为在剪断弹簧的一瞬间,弹力不能够突变.这种说法对吗?请看下面的例题. 相似文献
984.
本文新合成了荧光素单磷酸酯,通过元素分析、红外、热谱确定了其结构,探讨了其生成机理,并将其应用到酸性磷酸酯的荧光分析,深入研究了它与酸性磷酸酯酶之间反应的条件、检测此酶的线性范围、检测限和米氏常效. 相似文献
985.
区间判断的凸锥模型与排序方法 总被引:5,自引:2,他引:3
本文用凸锥模型对层次分析法中区间判断条件下的排序问题进行研究,给出了权重向量的合理算法.并对区间判断下权重向量的合理位置,产生逆序的可能性等重要问题进行了探讨和研究,给出了计算实例. 相似文献
986.
Kuanping Gong Yiming Yan Meining Zhang Lei Su Shaoxiang Xiong Lanqun Mao 《Analytical sciences》2005,21(12):1383-1393
This review addresses recent developments in electrochemistry and electroanalytical chemistry of carbon nanotubes (CNTs). CNTs have been proved to possess unique electronic, chemical and structural features that make them very attractive for electrochemical studies and electrochemical applications. For example, the structural and electronic properties of the CNTs endow them with distinct electrocatalytic activities and capabilities for facilitating direct electrochemistry of proteins and enzymes from other kinds of carbon materials. These striking electrochemical properties of the CNTs pave the way to CNT-based bioelectrochemistry and to bioelectronic nanodevices, such as electrochemical sensors and biosensors. The electrochemistry and bioelectrochemistry of the CNTs are summarized and discussed, along with some common methods for CNT electrode preparation and some recent advances in the rational functionalization of the CNTs for electroanalytical applications. 相似文献
987.
988.
In a Λ-type system employing a two-photon pump field, a four-wave mixing field can be generated simultaneously and, hence, a closed-loop system forms. We study theoretically the effect of the relative phase between the two incident fields on the generated four-wave mixing field and the electromagnetically induced transparency. It is found that the phase of the generated four-wave mixing field is the sum of the incident relative phase and a fixed phase that is irrelative to the incident relative phase. Hence, the total phase of the closed-loop system is independent of the incident relative phase. As a result, the incident relative phase has no effect on the electromagnetically induced transparency, which is different from the case of a Λ-type loop system closed by a third incident field. 相似文献
989.
Field analysis of a general chiral planar waveguide 总被引:1,自引:0,他引:1
Jianguo Xiao Keqian Zhang Lian Gong 《International Journal of Infrared and Millimeter Waves》1997,18(4):939-948
The propagation characteristics of general chiral planar waveguides are presented. This is the first time the eigen equation
is given in a simple formulation. The results indicate that there are two types of field distribution which is related to
the working wavelength and chiral admittance. When the chiral admittance is larger than a certain value, the fields of one
kind of circularly polarized wave in the core become exponentially damping in the transverse direction.
This work was supported by the “Foundations for the Ph.D Programs of China” 相似文献
990.
Tsao George T. Zheng Yizhou Lu Jean Gong Cheng S. 《Applied biochemistry and biotechnology》1997,63(1):731-741
Applied Biochemistry and Biotechnology - Phytic acid (myoinositol hexaphosphate) or its calcium salt, phytate, is an important plant constituent. It accounts for up to 85% of total phosphorus in... 相似文献