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11.
霍山窗与华东中强地震关系研究   总被引:10,自引:0,他引:10  
分析了1972 ̄1997年霍山窗小震的资料,研究了小震月频次、小震空间分布、P轴取向、P波初动等特征。认为当霍山窗小震月频次增高超过40次时应注意3个月内华东地区在佛子岭东北或西南方向500km内可能发生中强地震。未来地震的大小、距离和方位与震群中的最大震级及佛子岭台记录到的P波初动符号的一致性和空间特征有关。  相似文献   
12.
In this paper, the research progress of the Operational Earthquake Forecasting (OEF) is introduced from the major areas of concern, the concept of probability gain, hybrid model development,and the application to earthquake disaster reduction.Due to the development of OEF based on the global "Collaboratory for the Study of Earthquake Predictability (CSEP)" plan, it provides a significant technical foundation for earthquake forecast modeling and a practical foundation for solving the actual problems in earthquake preparedness and disaster mitigation.Therefore, related research and technical ideas provide inspirational and referential significance for earthquake forecasting/prediction.  相似文献   
13.
构建中国自然灾害防灾减灾新体系   总被引:1,自引:0,他引:1       下载免费PDF全文
在全面建成小康社会的决胜阶段即“十三五”时期,我国进一步加大了防灾减灾科技投入,以防灾减灾业务需求为导向,围绕国家战略部署和防灾减灾业务链、创新链实施了一批重大科技项目,形成了成灾理论研究、关键技术研发、仪器装备研制、应用示范、专业队伍建设等综合防范体系,为“十四五”我国新时期自然灾害防治创新体系的构建打下了坚实的基础,并促进了中国特色防灾减灾事业的持续稳固发展。  相似文献   
14.
As an important anthropogenic volatile organic compound(VOC), m-xylene has attracted numerous attentions due to its potential in secondary organic aerosol(SOA) formation. In this study, effects of aluminium dust seeds(boehmite and alumina) on SOA yield and aerosol size in m-xylene/NOx photo-oxidation were investigated in a 2 m3 smog chamber at 30°C and 50% relative humidity. Compared to the seed-free system, the presence of aluminium seeds resulted in an increase in the SOA yield, and also enhanced the O3 concentration in the chamber. The photolysis of O3 is a major source of OH radical, which is the most important oxidant of m-xylene. The increase in O3 concentration could result in the generation of more OH radicals, and finally contribute to the SOA formation. Seed particles influence the SOA size mainly by acting as condensation nuclei. Semi-volatile organic compounds(SVOCs) were condensed onto these nuclei, resulting in the increase in SOA size. However, when aluminium seeds with high concentrations were introduced into the system, SVOCs that had been condensed onto each particle were dispersed by these seeds, leading to the reduction in aerosol size.  相似文献   
15.
Three importantphysical processes occurringin contact binarysystems are studied. The first one is the effect of spin, orbital rotation and tide on the structure of the components, which includes also the effect of meridian circulation on the mixing of the chemical elements in the components. The second one is the mass and energy exchange between the components. To describe the energy exchange, a new approach is introduced based on the understanding that the exchange is due to the release of the potential, kinetic and thermal energy of the exchanged mass. The third is the loss of mass and angular momentum through the outer Lagrangian point. The rate of mass loss and the angular momentum carried away by the lost mass are discussed. To show the effects of these processes, we follow the evolution of a binary system consisting of a 12M and a 5M star with mass exchange between the components and mass loss via the outer Lagrangian point, both with and without considering the effects of rotation and tide. The result shows that the effect of rotation and tide advances the start of the semi-detached and the contact phases, and delays the end of the hydrogen-burning phase of the primary. Furthermore, it can change not only the occurrence of mass and angular momentum loss via the outer Lagrangian point, but also the contact or semi-contact status of the system. Thus, this effect can result in the special phenomenon of short-term variations occurring over a slow increase of the orbital period. The occurrence of mass and angular momentum loss via the outer Lagrangian point can affect the orbital period of the system significantly, but this process can be influenced, even suppressed out by the effect of rotation and tide. The mass and energy exchange occurs in the common envelope. The net result of the mass exchange process is a mass transfer from the primary to the secondary during the whole contact phase.  相似文献   
16.
STUDY ON UNIFIED INTER-SPHERICAL ACTING OF CONTINENTAL COLLISION OF TIBET PLATEAU  相似文献   
17.
I~ODWrIONExtraction of DNA from Porphyra po~nsis is very difficult due tO its high content ofpolysaccharides. TO avoid the interference Of POlysaccharides, HOng et al. (1992) used LiCI tosoften Porphyra thalli cells to release DNA directly without lysing the thalli, hoWever, the procedure is problematic in the isolation of high-quality DNA. Kitade et al. (1996) established a complicated procedure which includes the grindiflg of material in liquid nitrogen, lysing of material inextra…  相似文献   
18.
氧与铁分别为地球上丰度最高的元素与占地球质量最大的元素,它们所形成的化合物遍布我们的星球,具有-2价的氧控制着地球的氧逸度,随着深度的增加氧逸度逐渐降低,与铁所形成的氧化物中铁的价态也逐渐降低,O/Fe逐渐增加,近些年来科学家们发现深部地球条件下铁的一系列氧化物,其中具有高压黄铁矿结构的铁超氧化物FeO2具有最高的O/Fe,并且它还能够携带一定量的H(表示为Py-FeO2H,, x=0-1)。  相似文献   
19.
浙江方岩组之研究   总被引:2,自引:1,他引:1  
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20.
The modern change and evolution tendency of sand coast in the eastern area of Liaodong GulfMiaoFengmin;BiZhaoqi;LiShuyuan;Xia...  相似文献   
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