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381.
382.
太原台1985年至1991年的地应力、地倾斜、连通管和地电阻率4种前兆手段的月均值具有明显的正弦形年变规律,且在年变背景上出现年变幅度的增大或减小。前3种手段还叠加有趋势性上升或下降。用差值法定量地消除年变以后,无震时段变化平稳,有震时段异常突出,较好地反映了大同一阳高地区的中强地震。 相似文献
383.
安可士 《华北地质矿产杂志》1994,9(4):341-346
本文主题为饮用天然矿泉水。碳酸矿泉水,硅酸矿泉水,锶矿泉水是我国饮用天然矿泉水的主要类型,约占全国已发现矿泉水的95%。矿泉水主要生产国及消费国都在欧洲。亚洲的日本、韩国等国的矿泉水的产量也在大幅度增长。而我国矿泉水产量近年也以较大的速度增长,但只有名牌产品才有可观的经济效益。 相似文献
384.
利用底部剪力法对太原市(基本烈度为8度)一幢5层砖体结构的宿舍楼进行了抗震验算。根据计算结果,对该宿舍楼进行了震害预测,并对其结构的抗震性能给予了定性评价。 相似文献
385.
An Keshi 《GeoJournal》1980,4(6):507-513
Since the founding of the New China, the development and utilization of thermal spring resources in China have made rapid progress. Efforts were mainly devoted to the utilization of thermal springs in medical services before the end of the sixties. Since the 70's development of geothermal resources directed to multipurpose use in industry and agriculture has emerged with great vigour, with investigation and prospection of thermal springs undertaken in over two thirds of the provinces in China. Special geothermal exploration have been carried out in big cities where there are no natural thermal springs, and geothermal water has been found in city areas such as Beijing, Tianjin, Xian and Kunmin. In addition, hundreds of drill wells have tapped thermal water in the course of exploration and development of oil-gas fields.The present paper discusses the distribution and formation of thermal springs in China on the basis of the enormous data, unpublished data in particular, accumulated in the course of the above-mentioned effort.The author of this article wishes to express his sincere gratitude to the many organizations and colleagues for their numerous data and valuable suggestions and comments provided during the preparation of this article. 相似文献
386.
One hundred and seventeen oriented specimens of loess (in the form of cubes with an edge of 4 cm) were collected from the Wucheng loess section in Xixian County, Shanxi Province. After magnetic cleaning in an alternating field the remanent magnetization of specimens was measured with an astatic magnetometer (sensitivity 4×10?3 emu/cm3). The normally magnetized zone of the Brunhes normal epoch is recorded in upper Pleistocene Malan loess and middle Pleistocene Lishi loess which contain typical Zhoukoudian fauna. The reversely magnetized zone of the Matuyama reversed epoch is observed in lower Pleistocene Wucheng loess, whose fossils are found corresponding to Villafranchian Nihowan fauna. 相似文献
387.
The geography information system of the 1303 Hongton M=8 earthquake has been established. Using the spatial analysis function of GIS, the spatial distribution characteristics of damage and isoseismal of the earthquake are studies. By comparing with the standard earthquake intensity attenuation relationship, the abnormal damage distribution of the earthquake is found, so the relationship of the abnormal distribution with tectonics, site condition and basin are analyzed. In this paper, the influence on the ground motion generated by earthquake source and the underground structures near source also are studied. The influence on seismic zonation, anti-earthquake design, earthquake prediction and earthquake emergency responding produced by the abnormal density distribution are discussed. 相似文献
388.
Six species of more than 20-year-old desert woody plants in the oasis-desert ecotone were selected for study. The results showed that: (1) in different growing seasons δ13C values of assimilating organ varied between -14%. and -16%. for Haloxylon ammodendron (HA),-14%. - -15%. for Calligonum mongolicum (CM) and -25%. - -28%. for Caragana korshinskii (CK), Nitraria sphaerocarpa (NS) and Hedysarum scoparium (HS). (2) The net photosynthetic rate (Pn) of HA and CM was significantly higher than those of the other species. With the decrease in Pn for the six species, their intercellular CO2 concentration increased, but stomatal limitation value decreased under the intensive light. At the same time, the photochemical efficiency of PS II dropped to different degrees. (3) The CO2 enrichment experiment demonstrated that, Pn of HA and CM increased to different extent under 450 μmol/mol, but their Pn reduced or approximated to the current condition under 650 μmol/mol. Under 450 μmol/mol the efficiency for solar energy utilization of CK and HS significantly reduced and under 650 μmol/mol their respiration rate exceeded photosynthesis rate. It can be concluded that HA and CM have some function of pathway for C4 but the other three species have the function for C3. The decline in their Pn is mainly caused by non-stomatal factors. HA, CM, CK and HS exhibited photoinhibition, which disappeared in a short time. This is a kind of positive readjustment to adapting to the desert environment. HA and CM can adapt to the high CO2 environment, but CK and HS cannot. With the rise in atmospheric CO2 concentration and climate warming, the latter two species in the oasis-desert ecotone may be gradually degraded or even disappear. 相似文献
389.
东北亚地区夏季850 hPa南风异常与东北旱涝的关系 总被引:12,自引:3,他引:9
利用东北地区均匀分布的80个测站40年(1961~2000年)夏季月降水资料和同一时期北太平洋海温及NCEP/NCAR月平均再分析等资料,首先分析了东北亚地区夏季850 hPa南风异常特征,然后讨论了这种异常与东北降水的关系及其物理意义,最后给出了东北亚地区夏季南风异常的某些前兆特征.结果表明,东北亚地区夏季南风的强弱变化不仅与东北旱涝存在着十分密切的关系,而且对大范围大气环流异常也具有非常敏感的反应,东北亚地区南风异常的出现还具有前冬和前春北太平洋海温和500 hPa大气环流异常的前兆信号. 相似文献
390.