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91.
Complex scattering amplitudes are used to calculate the phase contrast of colloidal gold particles. Comparison of measurements of the phase contrast intensity at the centre of the gold particle as a function of defocus for unfiltered and zero-loss filtered images demonstrates the increase in phase contrast achieved by zero-loss filtering even for a thick carbon substrate film. The granulation of amorphous germanium films is measured by the spatial rms (root mean square) values of image intensity in a defocus series. 相似文献
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开发了以Ti4+为桥联剂制备无机-有机复合膜的新方法以自制的硅藻土多孔陶瓷为基膜(支撑体),使用浸涂法-热致相转化法相结合制备了TiO2-聚乙烯复合膜,并用红外光谱表征了复合膜层与层之间的结合方式和强度,支撑体中的SiO2通过Ti4+与聚乙烯的分子之间形成了新的化合物型膜层 相似文献
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Hironori Oda 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,63(3):223-228
Fluorans are given considerable attention as functional dyes for heat-and/or pressure-sensitive recording media. Numerous potential metal complexes were synthesised to prolong the life of coloured species. The protecting effect of these compounds against the photofading was examined on cellulose. It was found that the zinc or nickel salts of 3,5-dihydroxy-2-naphthoic acid and its derivatives can be applied as effective stabilisers against the fading of fluoran dyes. 相似文献
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Construction of the La Grande Complex in Eastern Canada called for complete or partial diversion of six rivers, the mean annual discharge of which varied from 60 to 1600 m3 s?1, and the transfer of water from two adjoining watersheds (1586m3 s?1) into La Grande Rivière. Three of these rivers with reduced flow, Eastmain (from 700 to 95m3 s?1), Opinaca (from 260 to 35m3 s?1), and Caniapiscau (from 1708 to 960m3 s?1) and the waterways with increased flows, Boyd-Sakami (from 1 to 811m3 s?1) and La Grande Rivière (from 1760 to 3400m3 s?1) were intensively monitored from 1978 to 1988, while the others were surveyed sporadically. Very few modifications were observed, compared to previous conditions, in banks stability, water quality, and aquatic fauna of the affected rivers: those which appeared can be explained by the water level fluctuations, the water quality of the tributaries of the residual drainage basin, and/or by the direct influence of the reservoirs. In James Bay, the areal extent of the Eastmain River and La Grand Rivière plumes varied with discharge in an exponential relation, mostly under ice cover; resources from the coastal environment had not yet undergone any major changes. Because of the very small population dwelling in the area, less than 3000 inhabitants, modifications in the hydrological regime of these rivers did cause relatively few impacts, the main being greater banks instability in specific locations, reduction of the thickness and ice cover on La Grande Rivière, enhancement of navigation constraints on Eastmain River, and higher mercury levels in fish related to operation of the reservoirs. 相似文献