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81.
82.
直流稳压电源可以将交流电压变换为直流电压,并使之稳定,在我们现实生活中应用很广泛,在实验中我们利用的电学知识,设计制造了一种直流稳压电源。本文简要介绍了这种直流稳压电源波形演示器的设计目的和电路原理,重点阐述了它的制作流程、滤波和稳压原理以及性能测试输出波形。 相似文献
83.
We consider the effects of quantum dot radius, confinement potential depth and controllable effective mass on the optical rectification coefficient (ORC) in spherical quantum dots, which is confined with Modified Kratzer–Coulomb Potential (MKCP). Using the Nikiforov–Uvarov method and compact density matrix theory, the ground state energy, ORC and wave function of electrons under the combined action of many factors are calculated. The results show that they affect the optical rectification response from different angles, including the position of peak and formant. 相似文献
84.
S. Marchetti P. Sandri R. Simili 《International Journal of Infrared and Millimeter Waves》1997,18(7):1395-1409
In this work we report a complete theory of the metal-insulator-metal, antenna coupled, mm and sub-mm detectors. The voltage-power
responsivity is simply derived from the geometrical antenna proprieties and the electrical junction characteristics. The calculated
responsivity simply foresees our experimental results in the sub-mm — mm range and well fits all the previously reported data 相似文献
85.
Romain Lecaque Samuel Grésillon Nicolas Barbey Romain Peretti Jean-Claude Rivoal Claude Boccara 《Optics Communications》2006,262(1):125-128
A new THz imaging system based on a local illumination by a near-field source is presented. Model object is imaged, and sub-wavelength spatial resolution is demonstrated for the first time to our knowledge with this configuration. The contrast and the resolution are confirmed by a theoretical study based on the diffraction in near-field zone. 相似文献
86.
Tyrosinase is an important enzyme in the metabolism of melanin and catecholamine, as well as an important antigen in autoimmunity of vitiligo. However, it is still a challenge to develop a selective and sensitive sensing approach for monitoring of tyrosinase in cell environment. In this work, a sensing strategy based on ion current rectification induced by nanochannels was established to electrochemically detect inactive tyrosinase. Functionalized alumina nanochannels were decorated by tyramine as an electrochemical platform to selectively determine tyrosinase via chemically specific reaction between phenolic hydroxyl groups of tyramine and tyrosinase. On the other hand, Fe2+ was further bonded with dihydroxyl groups generated by tyrosinase in nanochannels to amplify charge changes, resulting in the enhancement on the detection sensitivity for tyrosinase. Based on this principle, the developed electrochemical sensor showed a good linearity towards tyrosinase from 2 to 50 U/mL with a detection limit down to 0.83 U/mL, which can fulfil the requirement for detection of tyrosinase in cells. Eventually, the present electrochemical sensor was successfully employed in the selective and sensitive determination of tyrosinase in cell lysates. The results suggested that the activity of tyrosinase in B16 cells was 1.7-fold higher than that of Hela cells. 相似文献
87.
88.
In this paper, Cassava dregs are an outgrowth produced during starchy production which uses cassava as raw material. It is usually dropped out or used as cheap feedstuff. In order to make the best use of cassava dregs, increase industries' benefits and reduce castoffthis study developed a 'new technique which used cassava dregs as raw material to produce distilled spirits based on cassava dregs characteristics. The technique adopt solid-ferment procedure. At first, the ferment is processed by solid-state distilling, and then rectification extra care refinement; at last the tequila was produced with characteristics of simple and elegant fragrance and mellow-tasting. 相似文献
89.
CS1 PLC在乙醇精馏控制系统中的应用研究 总被引:1,自引:1,他引:0
乙醇精馏控制系统是将纯度为95%的乙醇经三重精馏生成无水乙醇.本文采用OMRON公司CS1 PLC及其内置回路控制板与模拟量单元构建过程控制系统,利用CX-Process Tool 软件完成模块流程图组态后下载到回路控制板中运行,实现了对精馏塔温度、液位及流量的自动控制.结果表明:该系统使用方便,具有良好的动态调整性能,极大提高了系统的稳定性、可靠性. 相似文献
90.
以探讨精馏的教学方法为目的,用定性分析方法,案例教学法,问题方法与对比法将精馏原理在精馏操作中的核心地位显现出来,从而增加学生理解,强化教学内容。 相似文献