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91.
根据国内12个大中城市的12个气象站实际测量的2008年5月份31天的天气最低温度和最高温度共744个数据,结合曲线图对其特征进行对比研究,表明:①南宁市和广州市的低温,北京市和济南市的高温、低温,该月最低值都出现在5月12日汶川地震当天;②其他城市该月低温最低值出现的时间为:哈尔滨市9日,西宁市10日,西安市、郑州市... 相似文献
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壳内部分熔融低速层及其研究意义 总被引:5,自引:0,他引:5
实验岩石学,岩石地球物理学,地质学及理论分析均表明,至少在具有高热流值的区段部分熔融作用可能是造成壳内低速带的主要原因,我们将由部分熔融作用所形成的壳内低速层称之为壳内部分熔融低速层,它是许多深部地质作用的发源和汇聚地,并影响和制约着地球物理场特征,因此,研究了壳内部分熔融低速带的形成及其地质意义无颖将深化人们对深部地质作用发生和发展过程的认识。 相似文献
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YUE Lixi MA Chunling and CHI Zhenming* UNESCO Chinese Center of Marine Biotechnology Ocean University of China Qingdao P.R.China 《中国海洋大学学报(英文版)》2006,5(4)
1IntroductionWater co-produced with oil and gas recovery istermed oil-field produced water.This water is consid-ered to be of the largest volume in the waste streamfromoil and gas production processes.The volume ofproduced water can be more than10ti mes t… 相似文献
95.
Guihua Wang Qinhua Fang Luoping Zhang Weiqi Chen Zhenming Chen Huasheng Hong 《Estuarine, Coastal and Shelf Science》2010,86(3):363-368
Hydropower development brings many negative impacts on watershed ecosystems which are not fully integrated into current decision-making largely because in practice few accept the cost and benefit beyond market. In this paper, a framework was proposed to valuate the effects on watershed ecosystem services caused by hydropower development. Watershed ecosystem services were classified into four categories of provisioning, regulating, cultural and supporting services; then effects on watershed ecosystem services caused by hydropower development were identified to 21 indicators. Thereafter various evaluation techniques including the market value method, opportunity cost approach, project restoration method, travel cost method, and contingent valuation method were determined and the models were developed to valuate these indicators reflecting specific watershed ecosystem services. This approach was applied to three representative hydropower projects (Daguan, Xizaikou and Tiangong) of Jiulong River Watershed in southeast China. It was concluded that for hydropower development: (1) the value ratio of negative impacts to positive benefits ranges from 64.09% to 91.18%, indicating that the negative impacts of hydropower development should be critically studied during its environmental administration process; (2) the biodiversity loss and water quality degradation (together accounting for 80–94%) are the major negative impacts on watershed ecosystem services; (3) the average environmental cost per unit of electricity is up to 0.206 Yuan/kW h, which is about three quarters of its on-grid power tariff; and (4) the current water resource fee accounts for only about 4% of its negative impacts value, therefore a new compensatory method by paying for ecosystem services is necessary for sustainable hydropower development. These findings provide a clear picture of both positive and negative effects of hydropower development for decision-makers in the monetary term, and also provide a basis for further design of environmental instrument such as payment for watershed ecosystem services. 相似文献
96.
The marine yeast strain N13d, producing an extracellular amylase, was isolated from the deep sea sediments of the Pacific
Ocean. This strain was identified to be Aureobasidium pullulans by 18S rRNA gene sequence analysis and routine yeast identification methods. The optimal sea water medium for amylase production
by this yeast strain was 1.0% peptone and 1.0% soluble starch with pH 4.0. The optimal conditions for amylase production by
this yeast strain were with temperature 28 °C, aeration rate 6 Lmin−1 and agitation speed 250 rmin−1. Under these conditions, 58.5 units of amylase activity per mg protein were produced within 56 h of fermentation. 相似文献
97.
Characteristics of ground motion at permafrost sites along the Qinghai-Tibet railway 总被引:1,自引:0,他引:1
Lanmin Wang Zhijian Wu Junjie Sun Xinfu Liu Zhenming Wang 《Soil Dynamics and Earthquake Engineering》2009
Based on 14 typical drilling holes distributed in the permafrost areas along the Qinghai-Tibet railway, the distribution of wave velocities of soils in the permafrost regions were determined. Using results of dynamic triaxial tests, the results of dynamic triaxiality test and time histories of ground motion acceleration in this area, characteristics of ground motion response were analyzed for these permafrost sites for time histories of ground accelerations with three exceedance probabilities (63%, 10% and 2%). The influence of ground temperature on the seismic displacement, velocity, acceleration and response spectrum on the surface of permafrost were also studied. 相似文献
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动态部分熔融作用及其地球物理意义 总被引:7,自引:1,他引:7
本文着重阐述了上地幔动态部分熔融动力学的几个基本问题:(1)初始熔融物的产生;(2)渗透和萃取;(3)运移和聚集;(4)研究方法、内容及其地球物理意义。笔者强调指出,在初始熔融阶段,两面角是控制上地幔熔融物的几何分布、渗透性和连通性能的关键参数,少量熔融物(2%~5%)不仅会使软流圈中地震波速下降、导电率增加,而且还引起上地幔非弹性衰减现象。 相似文献