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71.
本文针对房屋分层分户面积测算特点,设置三个级别功能模块及流程,运用灵活方便的绘图与编辑功能,采集面积自动校验功能及合理的分摊方法、步骤,科学合理地开发出一套方便实用,面积分摊计算和管理系统。 相似文献
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-The reclamation rate formula for concentrating tritium by the addition of "regular and quantitative aqueous sample" is advanced.Effects of different adding modes on reclamation rate and the reclamation rate reappearance are studied; and the analytic program of tritium in seawater is also proposed. By using Fe-Ni electrodes and the electrolysis temperature of 2± 0. 5℃, β value reaches 20. Reclamation rates reach 83% and 76% when 250 cm3 and 500 cm3 seawater is concentrated to 8 cm3.The relatively appropriate toluene/Trition ratio for counting aqueous sample under the normal temperature is proposed.The computer program of different addition electrolytic concentrations for measuring tritium is coded, and the tritium data base is established. 相似文献
74.
闽江口底沙运动的放射性示踪法研究 总被引:2,自引:0,他引:2
本文报道了在福建省首次进行的应用放射性示踪法观测闽江口底沙运动的研究结果。详细叙述了放射性示踪沙的实验方法,结合水文和地质资料具体分析了实验结果,为外沙抛泥区的选择和内沙航道增深工程提供了科学依据。 相似文献
75.
本文报道了我们在应用放射性示踪沙观测闽江口底沙运动的实验过程中,同时进行的现场辐射剂量监测和实验区周围环境的放射性污染监测方法和结果,并进行了辐射安全分析和环境污染评价。 相似文献
76.
ZENG Xianzhang QIU Manhu YIN Mingduan ZENG Wenyi HE Jianhu WAN Xueguo CHEN Hengliang LI Jing TAN Baozeng 《海洋学报(英文版)》2007,26(3):73-83
A low-level β counting-α spectrum apparatus used for the detection of the β radiation of thorium-234 and α spectrum of thorium-228 simultaneously and an easy operating procedure for the enrichment, radiochemical separating, sampling and measurement of thorium-234 and uranium-238 in the ocean are developed based on the requirements of analyzing export productivity in the euphotic zone via thorium-234-uranium-238 radioactivity disequilibrium. The detecting efficiency both of β and α radiation is higher than 20%. The background of β radiation is less than 0.5 min-1, and the energy resolution of α detector is better than 1%. Total recycle ratio of thorium-234 is about 75%. Using the above apparatus and procedure, the radioactivities of dissolved thorium-234 and uranium-238, particle thorium-234 and uranium-238 in seawater of the South China Sea, the Southern Ocean and the Arctic Ocean were analyzed. 相似文献
77.
JIN Ruoshi MIAO Peisen SIMA Xianzhang LI Jianguo ZHAO Hualei ZHAO Fengqing FEN Xiaoxi CHEN Yin CHEN Lulu ZHAO Lijun ZHU Qiang 《《地质学报》英文版》2016,90(6):2104-2116
In Northern China, sandstone-type uranium (U) deposits are mostly developed in Mesozoic-Cenozoic basins. These U deposits are usually hosted in unvarying horizons within the basins and exhibit typical U-forming sedimentary associations, which is referred to as U-bearing rock series. This study describes the structural features of U-bearing rock series within the main Mesozoic-Cenozoic U-producing continental basins in Kazakhstan, Uzbekistan, and Russia in the western segment of the Central Asian Metallogenic Belt (CAMB), and Northern China in the eastern segment of the CAMB. We analyze the basic structural conditions and sedimentary environments of U-bearing rock series in Northern China and classify their structural styles in typical basins into river valley, basin margin, and intrabasin uplift margin types. The intrabasin uplift margin structural style proposed in this study can be used to indicate directions for the exploration of sandstone-type U deposits hosted in the center of a basin. At the same time, the study of structural style provides a new idea for exploring sandstone-type U deposits in Mesozoic-Cenozoic basins and it is of great significance to prospecting of sandstone-type uranium deposits. 相似文献
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本文介绍了光学相衬显微术的基本原理、方法和应用。光学相衬显微术能够观察到用普通显微术无法观察到的透明活体微生物的细微结构,50年代应用到矿物晶体微形貌学中,进行晶体表面生长的动态观察。笔者主要用来观察透明矿物晶体的结晶状态及显微构造。观察的结果表明,运用这种方法在地学研究中将会发现一些未曾开发的新内容。 相似文献
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