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71.
Zhu Qian Luo Yulin Zhou Dongyang Xu Yue-Ping Wang Guoqing Tian Ye 《Natural Hazards》2021,105(2):2161-2185
Natural Hazards - Droughts have caused many damages in many countries and might be aggravated around the world. Therefore, it is urgent to predict and monitor drought accurately. Soil moisture and... 相似文献
72.
Acta Geotechnica - Suffusion is a typical form of internal erosion for gravel soils in which fine particles are detached by seepage and transport by water through pores. The prediction of erodible... 相似文献
73.
大地形上空偶极子东移对热带气旋路径的影响 总被引:1,自引:0,他引:1
With a quasi-geostrophic barotropic model on the β-plane with a topography term, 16 experiments were performed with an integration period of 6 days. The interaction between tropical cyclone tracks and 500 kin-scale vortices originating from the western part ora large-scale topography is investigated. It is suggested that this kind of interaction may have a significant impact on the moving speed and direction of tropical cyclones. Under certain conditions, this interaction may be a factor in causing an abnormal tropical cyclone track. Furthermore, the effect of large-scale topography plays an important role in the formation of unusual tropical cyclone tracks. 相似文献
74.
降雨及地下水对边坡稳定性动态影响的初步研究 总被引:8,自引:0,他引:8
论述了降雨及地下水对边坡稳定性的动态影响及作用特征。这种影响特征具有典型的周期性和滞后性,通过对坡体地下水位的动态模拟,取得了边坡稳定性随时间而变化的规律认识。 相似文献
75.
As the two large developing and populous countries, China and India face the dual challenges of economic development and climate change. Both of them are active in carbon emissions reduction, while India also bears the pressure of being “benchmarked” against China. With taking China and India as the sample of a comparative analysis, and the statistical value of a long sequence as the basic analysis data, based on the detailed analysis and comparison of carbon emissions history, the carbon emissions situation of the two countries from various dimensions including economic development, energy reserves and consumption, etc. were comparatively analyzed. The carbon intensity and energy structure after achieving the objectives were measured and compared by focusing on the carbon emissions reduction targets in China and India. The comparative results show that: China’s total carbon emissions are greater than India’s, but the growth rate of emissions, per capita emissions are significantly lower than India’s, while the carbon intensity decreases significantly faster than that of India. China has taken more efforts to make commitments to carbon reduction than India. With India’s energy structure adjustment, the situation will be gradually better than that in China. 相似文献
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78.
Luo Yan Liu Yongsheng Hu Shenghong Gao Shan Open Laboratory of Constitution Interaction Dynamics of the Crust Mantle System Ministry of National Lands Resources China University of Geosciences Wuhan Lin Shoulin Faculty of Material Sc 《中国地质大学学报(英文版)》2001,12(3)
INTRODUCTIONLaserablationinductivelycoupledplasmamassspectrome tryisanincreasinglydevelopedanalyticaltechniqueforsolidsampleanalysis.LA ICP MSoffersattractivecharacteristicsofhighsensitivity ,lowdetectionlimits,minimalsampleprepara tion ,lessoxidesinterfe… 相似文献
79.
The accurate and precise determination of Li isotopic composition by MC‐ICP‐MS suffers from the poor performance of traditional column chromatography. Previously established chromatographic processes cannot completely remove Na in complex geological samples, which is currently interpreted to be a result of Na breakthrough. In this study, Na breakthrough during single‐column purification was found to differ between simply artificial Na‐containing sample solutions, where a little Na residue was found, and silicate rocks, where a large amount of breakthrough occurred. A revised two‐step column purification for Li using 0.5 and 0.3 mol l?1 HCl as eluents was designed to remove the Na. This modified method achieves high‐efficiency Li purification from Na and consequently avoiding high Na/Li ratio interference for subsequent MC‐ICP‐MS analyses. The proposed method was validated by the analysis of a series of reference materials, including Li2CO3 (IRMM‐016, ‐0.10‰), basalt (BCR‐2: 2.68‰; BHVO‐2: 4.39‰), andesite (AGV‐2: 6.46‰; RGM‐2: 2.59‰), granodiorite (GSP‐2: ?0.87‰) and seawater (CASS‐5, 30.88‰). This work reports early Na appearance prior to the elution curves in chromatography and emphasises its influence for subsequent Li isotope measurement. Based on the findings, the established two‐step method would be more secure than single‐column chemistry for Li purification. 相似文献
80.
为了准确模拟预测地下水源热泵系统运行期间的地下水渗流场与温度场的变化规律,避免未来地下水源热泵系统运行期间出现的冷热贯通现象与堆积问题,科学合理地设计地下水源热泵系统。以江苏南通益兴集团地下水源热泵示范工程为例,建立了地下水渗流与热量运移三维耦合数值模型,并结合地下水源热泵系统的设计运行方案,预测分析了未来地下水源热泵系统的热平衡发展趋势。结果表明,该工程按设计方案运行,整个区域地下水温度逐渐升高,出现热堆积问题。采用春秋季与冬季多加热生活用水增加制热负荷量的方法,可有效缓解热堆积问题。 相似文献