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991.
KLTS-2型矿用电缆综合探伤仪的使用与改进 总被引:1,自引:0,他引:1
琚翠萍 《科技情报开发与经济》2004,14(3):233-234
介绍了电缆故障的种类,阐述了KLTS-2型电缆探伤仪的工作原理与结构特点,指出了KLTS-2型电缆探伤仪在使用过程中的优缺点,对其故障原因进行了简要分析并提出了改进措施。 相似文献
992.
本文用几何光学基本定律对两种不同外形发光管的光学性能作了一般性的分析和探讨。通过具体的计算,从等效发光点、可被利用光能、聚光性能和使用场合等方面对它们进行了比较,用以指导光路设计,并提出了改进建议 相似文献
993.
Near infrared spectroscopy (NIR) was used to characterize the nature of specific interactions in blends of lightly sulfonated polystyrene ionomers (M‐SPS where M = Zn+2, Mn+2, or Li+) and polycaprolactam (PA6). The assignments of the NIR overtone bands that arise due to the interactions between the cation of the ionomer, and the amide groups were made using spectra of model compounds. The relative populations of the different environments of the N? H groups were qualitatively determined by deconvoluting the NIR spectra into five absorbances representing hydrogen‐bonded N? H in crystalline and amorphous phases and an ion‐amide complex. The ion‐amide complex was specific for the blends. The interpolymer interactions were sensitive to composition and temperature, but qualitatively the behavior was the same for all three ionomer salts investigated. © 2008 Wiley Periodicals, Inc. JPolym Sci Part B: Polym Phys 46: 1602–1610, 2008 相似文献
994.
G. J. de Jong N. Lammers F. J. Spruit U. A. Th. Brinkman R. W. Frei 《Chromatographia》1984,18(3):129-133
Summary A peroxyoxalate chemiluminescence detection system for liquid chromatography is described. The excitation of fluorophores is generated by the reaction of bis-(2,4,6-trichlorophenyl)oxalate or bis(2,4-dinitrophenyl)oxalate and hydrogen peroxide, which are added to the column effluent. The influence of the solvents and the concentrations of the reagents have been investigated. The influence of the flow cell volume on sensitivity and on band broadening have also been studied and a chemical band narrowing effect has been observed. Different types of apparatus have been compared for detection of the emitted light. The system has been used for the detection of the dansyl derivative of a drug with a secondary amine functional group in serum samples. The detection limits are in the 1–10pg range. 相似文献
995.
996.
997.
A liquid chromatography system with a potentiometric microelectrode at the exit end of an open-tubular LC column of 3.5m i. d. nearly shows the theoretically [2, 10] predicted performance of 980 000 theoretical plates for non-retained components at a retention time of a few minutes. Possibilities of controlling the position of the microelectrode tip are given. A distance of one column i. d. between detector and column leads to a loss in column performance of about 15%. 相似文献
998.
V. V. Ammosov E. M. Gushchin S. V. Somov M. K. Timofeev V. A. Ryabov G. I. Tipografschik 《Radiation measurements》1995,25(1-4):183-184
The new type of a solid state track detector is described. The detector consists of the fibre or capillary target and the multistage image intensifier. The standard microchannel plate filled with liquid scintillator and the input fibre plate of the image intensifier was investigated as the targets. 相似文献
999.
The crystallization process of the thermoplastic polyimide derived from 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) and 2,2-dimethyl-1,3,-(4-aminophenoxy) propane (DMDA) is studied at the molecular level by utilizing infrared spectroscopy's sensitivity to local molecular environment. Assignments of the unique spectral features appearing upon crystallization are made with additional verification from crystalline model imide compounds. A direct comparison of an annealed polyimide film studied by both infrared spectroscopy and x-ray diffraction shows fairly close agreement in the amount of crystallinity obtained. The unique crystalline infrared spectral features provide insight into the molecular mechanism involved with the crystallization process. Spectral shifts occurring upon crystallization reflect intramolecular rotations toward increased coplanarity as well as intermolecular chain packing of certain molecular groups at specific sites of the chain backbone. The site specific information is then used to study the relative kinetic behavior of the intramolecular and intermolecular effects occurring during crystallization. © 1994 John Wiley & Sons, Inc. 相似文献
1000.