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161.
The C and H isotopic compositions of the methane in more than 160 gas samples from 10 basins in China are presented in this paper.The natural gases are classified as four types: biogenic gas ,bio-thermocatalytic transitional gas, gas associated with condensate oil ,and coal-type gas. The isotopic compositions of these gases closely related to the depositional basins, the types of organic matter,the stages of thermal evolution and the genetic characteristics of different gas reservoirs.Studies of the C and H isotopic compositions of terrigenous natural gases will provide valua-ble information on the prospecting and development of natural gases of different genetic types. 相似文献
162.
Information on fatalities from lightning strikes has been extracted from a specially compiled database on natural hazards in Australia. Records dating from 1803–1991 indicate that at least 650 persons have been killed by lightning strikes. Maps and charts show the percentages of victims with respect to age, sex, locality, activity, and other circumstances of the strike. The majority of the 650 fatalities recorded have occurred along the more populous southeastern coast. The overall death rate, from 1910–1989, is 0.08 per 100 000 population. The annual number of lightning fatalities has decreased with time, from a death rate of 0.21 in 1910–1919 to 0.01 in 1980–1989. This trend is more pronounced when population figures are taken into account. The group that has been most at risk in Australia is that of males aged 15–19, followed by males aged 20–34. The male:female ratio of victims has decreased with time but is not approaching equality, being 11.6 in 1910–1919 and 5.3 in 1980–1989. The diurnal and monthly occurrences of lightning fatalities peak at 12.00–18.00 hours and November-February respectively. About 86% of fatalities have occurred outdoors and 14% have occurred indoors. Approximately three-fifths of fatalities have been work-related, and the group of workers that has traditionally been most at risk is that of land-workers. Approximately one-fifth of fatalities have been recreation-related, although this proportion has been increasing with time. The recreational activities of water sports, golf, and cricket have had the greatest number of lightning fatalities. Comparisons are made between these data and the results of other similar studies, both in Australia and overseas. 相似文献
163.
韩凤财 《华北地质矿产杂志》1994,9(4):365-368
经勘察评价和国家级评审鉴定,天镇县城关T_(67)井属锂-锶-偏硅酸三项达标的复合型优质饮用天然矿泉水。矿泉水产于近东西向挽近断裂带上,马圈痒地热田边部,地势平坦,环境无污染,交通便利,水质独特,水量丰富,具有综合开发优势,适宜建厂开发。 相似文献
164.
孙富国 《华北地质矿产杂志》1994,9(4):476-480
王村矿泉水为松散岩类孔隙水和碎屑岩裂隙水的混合水。它受深循环远源补给。矿泉水的动态稳定、水质优良、口感纯正,属锶—偏硅酸饮用天然矿泉水,是山西较好的饮用矿泉水源之一,有良好的开发前景。稷山南阳矿泉水是一个含锶—锌—偏硅酸等多种微量元素的重碳酸硫酸钠型饮用天然矿泉水。该矿泉水处于侯马断陷盆地内次一级断裂的复合部位,赋存于中更新统中下部的中细砂层中。水量丰富,涌水量可达800m ̄3/d。此矿泉水动态稳定,口感纯正,产地环境优美,无任何污染。自1988年发现,1989年开发利用至今,该矿泉水、矿泉饮料畅销不衰,是一处具有发展远景的优质矿泉水。 相似文献
165.
魏文革 《华北地质矿产杂志》1994,(4)
东亢矿泉水处于临汾断陷盆地边缘山前地带。矿泉水赋存于石炭系、奥陶系及侵入岩体的裂隙中。单井涌水量达71.4m ̄3/h,水位埋深51.09m。矿泉水中锌、锶、偏硅酸分别为0.289mg/L,1.28mg/L,33.28mg/L,属锌锶偏硅酸-重碳酸·硫酸-钠型优质矿泉水,具有良好的开发前景。 相似文献
166.
本文对1987—1993年间,山西50个矿泉水点101份饮用天然矿泉水细菌总数和总大肠菌群进行了检验,其中64份合格,合格率为63;37%。表明山西饮用天然矿泉水源受微生物的污染较为严重,污染程度与水源出露形式和季节变化关系不明显,而主要与矿泉水出露环境的防护措施有密切关系。 相似文献
167.
168.
中国主要自然致灾因子的区域分异 总被引:34,自引:2,他引:34
依据102种自然致灾因子分布图,以县域为统计单元,建立了全国自然致灾因子数据库。在此基础上,绘制出中国自然致灾因子多度、相对强度、被灾指数图,进而分析了它们的区域分异,为进行中国自然灾害区划提供依据。 相似文献
169.
Derek L Smith 《The Australian geographer》1995,26(1):61-70
This paper compares pastoralists in South Australia in the nineteenth century with Australian mining companies in the twentieth century as they resist the efforts of government to extract a greater proportion of the wealth created in the exploitation of natural resources. In effect, in both cases the struggle relates to the allocation of economic rent between private and corporate capital on the one hand, and the owners of the resources, the people of Australia, on the other. It is difficult not to be impressed by the similarities in the ideologies, objectives and strategies of these two groups of resource exploiters, separated though they are by over one hundred years. 相似文献
170.
本文利用EXAFS方法对镁铝榴石、几种锰矿和不同铁含量的闪锌矿中有关阳离子的近邻结构进行了研究,得到了有关阳离子在相应矿物中的近邻结构参数.对闪锌矿的研究,得到了杂质Fe绝大部分以六配位的形式存在的结果,这与传统的观点不同;提出了闪锌矿不仅可作为地质温度计,还可能作为地质温度、压力变化记录仪的设想。 相似文献