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131.
全国重要矿产总量预测方法   总被引:11,自引:0,他引:11  
全国重要矿产资源评价涉及25种重要矿产的近百种矿床类型,需要在1∶20万尺度水平圈定成矿预测远景区,并科学估算各远景区资源量,为国家矿产资源战略勘查和战略部署提供技术支撑。为了保证预测成果在同一层面上进行全国汇总,制定了全国一致的、标准的技术要求和方法。通过对中国以往一轮、二轮区划预测方法、全国矿产资源总量预测方法及国外最新预测方法的分析和总结,结合近年来预测理论的新发展,确定了全国重要矿产总量预测的理论基础是成矿系列理论、现代成矿动力学理论和综合信息矿产预测理论,采用的预测思路是矿床模型综合地质信息预测方法。文章陈述了总量预测的方法流程和预测技术要求,有关方法思路可供资源评价人员参考。  相似文献   
132.
区域数字地震台网实时速报系统研究   总被引:8,自引:2,他引:6  
根据我国地震监测台网的发展趋势,提出了区域数字地震台网实时速报系统的发展目标,研究了实现这一目标应解决的实时数据流接收、震相自动识别、震相可靠性处理、实时地震定位、震相到时等值线实时绘制、地震震级的实时计算、地震动强度分布图的实时绘制等问题.我们编制了一套实时地震速报软件,实现了上述功能,并用福建数字地震台网记录的地震事件进行软件功能测试.测试结果表明:对于网内地震,软件处理结果基本达到中国地震局地震速报评比满分的要求,速报时间缩短至30~50 s.此外,通过实时仿真技术,系统可给出实际观测到的PGA、PGV、PGD等值线图,可以为应急救灾确定重灾区和有感范围提供帮助.  相似文献   
133.
Modern meteorological observations in South China from 1960 to 2009 show a strong correlation between winter temperatures and two snowfall parameters, the southern boundary of the snow and the number of snowy days. Based on this relationship, the variation in annual winter mean temperature in South China from 1736 to 2009 was reconstructed using data acquired from Chinese historical documents dating from the Qing dynasty, such as memos and local gazettes. The reconstructed time series were used to analyse variations in winter temperature in South China. Significant interannual and interdecadal changes were found. The maximum temperature difference between neighbouring years was 3.1 °C for 1958–2009 and 3.0 °C for 1736–1957, whereas the maximum temperature difference between adjacent decades was 0.8 °C for the 1960s–2000s and 0.6 °C for the 1740s–1950s. The 2000s was the warmest decade; the mean temperature was 1.6 °C higher than that of the 1870s, which was the coldest decade between the 1740s and the 2000s. The mean winter temperature was warmer in the 18th and 20th centuries and coldest in the 19th century.  相似文献   
134.
This paper presents an analytical solution for the lateral dynamic response of a pipe pile in a saturated soil layer. The wave propagations in the saturated soil and the pipe pile are simulated by Biot's three‐dimensional poroelastic theory and one‐dimensional elastic theory, respectively. The governing equations of soil are solved directly without introducing potential functions. The displacement response and dynamic impedances of the pipe pile are obtained based on the continuous conditions between the pipe pile and both the outer and inner soil. A comparison with an existing solution is performed to verify the proposed solution. Selected numerical results for the lateral dynamic responses and impedances of the pipe pile are presented to reveal the lateral vibration characteristics of the pile‐soil system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
135.
The Integrated Biosphere Simulator is used to evaluate the spatial and temporal patterns of the crucial hydrological variables [run‐off and actual evapotranspiration (AET)] of the water balance across China for the period 1951–2006 including a precipitation analysis. Results suggest three major findings. First, simulated run‐off captured 85% of the spatial variability and 80% of the temporal variability for 85 hydrological gauges across China. The mean relative errors were within 20% for 66% of the studied stations and within 30% for 86% of the stations. The Nash–Sutcliffe coefficients indicated that the quantity pattern of run‐off was also captured acceptably except for some watersheds in southwestern and northwestern China. The possible reasons for underestimation of run‐off in the Tibetan plateau include underestimation of precipitation and uncertainties in other meteorological data due to complex topography, and simplified representations of the soil depth attribute and snow processes in the model. Second, simulated AET matched reasonably with estimated values calculated as the residual of precipitation and run‐off for watersheds controlled by the hydrological gauges. Finally, trend analysis based on the Mann–Kendall method indicated that significant increasing and decreasing patterns in precipitation appeared in the northwest part of China and the Yellow River region, respectively. Significant increasing and decreasing trends in AET were detected in the Southwest region and the Yangtze River region, respectively. In addition, the Southwest region, northern China (including the Heilongjiang, Liaohe, and Haihe Basins), and the Yellow River Basin showed significant decreasing trends in run‐off, and the Zhemin hydrological region showed a significant increasing trend. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
136.
张正奇  丁义平 《岩矿测试》1990,9(3):169-172
本文研究了钴(Ⅱ)-5-Br-PADNm络合物的光度性质。在pH5.0缓冲溶液中,有TritonX-100存在时,Co~(2 )与5-Br-PADNm形成1:2红色络合物,λ_(max)为547nm,ε为1.35×10~5l·mol~(-1)·cm~(-1)。所提出的方法用于矿石及茶叶中Co的测定,得到满意结果。  相似文献   
137.
本文以中国主要河流(100多条河流,177个站)年径流资料为基础,采用近代随机水文学方法,并结合年径流的成因分析,探讨了中国主要河流年径流序列的趋势性、近似周期性、相依性和持续性特点。还研究了它们的分区变化规律。  相似文献   
138.
Climatic study on the summer tropical easterly jet at 200 hPa   总被引:2,自引:0,他引:2  
The low latitude easterlies at 200 hPa in summer (May-October) is analysed climatically during the 13-year period from 1968 to 1980, with a special emphasis on the relationship between the anomalous tropical easterly jet stream over South Asia and the low latitude atmospheric circulation, and also the summer monsoon precipitation in India. The compositing analysis shows that the tropical easterly jet stream over South Asia has five anomalous patterns at 200 hPa i.e. the western pattern, middle pattern, eastern pattern, two-branch pattern and multi-core pattern. Evidence has shown that the precipitaion in India anomalously increased during the anomalous period of the western pattern and the middle pattern, but reverse case is true in the eastern pattern. Some different anomalies of the precipitation in different area of India were found during the other two anomalous pattern.  相似文献   
139.
By the use of space-time spectral analysis and band-pass filter, some of the features of the medium-range Oscillations in the summer tropical easterlies (10oS-20o) at 200 hPa are investigated based on a two-year (1980 and 1982) wind (u, v) data set for the period from May to September. Space-time power spectral analysis shows that the total energy of the westward moving waves was the largest and that of the standing waves and eastward moving waves was relatively small in the 200 hPa easterlies; the total energy of the eastward moving waves was at minimum at 10oN. Three kind of the medium-range oscillations with about 50 day, 25 day and quasi-biweekly periods were found in the easterlies, which all show a remarkable interannual variation and latitudinal differences in these two years. The wave energy of zonal wind is mainly associated with the planetary waves (1-3), which all may make important contributions to the 50 day and 25 day oscillations in different years or different latitudes. The quasi-biweekly oscillation is mainly related to the synoptic waves (4-6). In equatorial region, the 50 day oscillation was dominant with a eastward phase propagation in 1982 while the dominant oscillation in 1980 was of 25day period with a westward phase propagations in 1980. Both of them are of the mode of zonal wavenumber 1. Strong westward 50 day oscillation was found in 10oN-20oN in these two years. Regular propagations of the meridional wind 50 day oscillation were also found in the easterlies.The 50 day and 25 day oscillation of zonal wind all demonstrate southward phase propagation over the region of the South Asia monsoon and northward phase propagation near interational date line, where are the climatic mean position of the tropical upper-tropospheric easterly jet and the tropical upper tropospheric trough (TUTT), respectively.  相似文献   
140.
本文用近13年200hPa高空风资料得到了夏半年(5—10月)逐月平均全球热带风场,发现如下一些主要结果: (1)在亚洲地区对流层上部反气旋存在两个中心;一个在青藏高原上空;一个在伊朗和阿富汗地区。两者的演变不同。伊朗高压的北推和撤退都比青藏高原上的早。北美墨西哥高压的变化在时间上与伊朗高压很相似。 (2)北太平洋中部高空槽(TUTT)出现在5—10月,8月份最强,位置最北;北大西洋中部高空槽出现在5—9月,7—8月最强。 (3)南半球冬季有三个主要的长波脊和长波槽,分别位于大陆以西和以东海区。  相似文献   
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