检索结果-南通市图书馆

Episodes 2005年第1期28卷 59-60页

作者： pasava, j Czech Geol Survey Prague 11821 1 Czech Republic

It has been a tradition to organize very successful UNESCO Postgraduate Courses on Geochemical Prospecting Methods in the former Czechoslovakia from mid 70's. The first certificated course-GEOCHIM PRAHA UNESCO 1975 was launched on September 5, 1975 and lasted till October 25,1975. Since that time this course has been organized biannually by the Czech Geological Survey in Prague together with the Dionyz SEtúr Geological Survey in Bratislava and sponsored by the Division of Earth Sciences (UNESCO/Paris) and the International Association of Geochemistry and Cosmochemistry (IAGS). The course was specialized on both theoretical and practical training in classical geochemical prospecting methods.

关键词：研究生毕业训练课程地球化学开发方法环境应用

波希米亚地块黑色页岩与其他地区黑色页岩中铂族元素分布的对比

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

四川地质科技情报 1996年第3期 33-36页

作者： pasava,j

波希米亚黑色页岩与其它地区黑色页岩中铂族元素分布的对比

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

国外地质（成都） 1992年第3期 33-37页

作者： pasava,j 刘家军

Geochemistry and origin of tin-polymetallic sulfide deposits hosted by the Devonian black shale series near Dachang,Guangxi,China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geochemistry and origin of tin-polymetallic sulfide deposits...

中国科学院地质与地球物理研究所2004学术年会

作者： j.pasava B.Kribek P.Dobes I.Varrin K.Zak Czech Geological Survey Klarov 131.118 21 Praha 1Czech Republic

Two tin-polymetallic sulfide deposits hosted by the Devonian black shale series of the Guangxi Zhuang Autonomous region occur in the Dachang ore *** Upper Devonian(Frasnian Epoch) black shale series contains the giant Tongkeng-Changpo deposit,and the Middle Devonian(Givetian Epoch) reef limestone contains the giant Longtoushan *** rocks occur at Lame and the western part of *** occur as stratified bodies,large veins,stockworks and zones of *** are massive,banded,laminated and *** ores contain more than 180 different minerals,the most important of which are cassiterite,sulfides and *** laminated sedimentary sulfide ores occur at *** mean ratio of SiO/AlO for shale-marl is 3.5,but values averaging 56 and 67,respectively,for ore and chert suggest a biogenic or hydrothermal source for *** and country rocks are rich in Sb,Pb,*** and Cu;granites are rich in Sb,W. Zn and *** elements,such as Te,Cd,Se ***,are abundant in ores,country rocks and granites,implying contributions of sedimentary and intrusive activities to the ore *** Y/Ho values for the black shale series(28) and granite(31) are similar to most shales and most volcanic rocks;the Y/Ho value for reef limestone is *** to sea *** black shale series are slightly LREE-enriched on chondrite-normalized plots and show small negative Eu anomalies:meanδEu(0.56),δCe(0.9) and Ce(- 0.07) values suggest a shallow-water deposition near the redox boundary. TheδS values of sulfides from various deposits of Dachang vary with theδS values for Lame ranging from - 2‰to + 2‰, and values for Tongkeng-Changpo ranging from - 4.9‰to + 2.6‰.The highly negativeδS values(- 9.5‰to - 11.3‰) of Huile and Kengma sulfides suggest the important role of biogenic *** meanδC value of organic matter of Devonian black shale series is - 24.6‰.TheδSi values of Upper Devonian black chert are 0.2 -0.3‰,indicating a sedime

关键词： Giant tin polymetallic sulfide deposits Dachang Devonian Black shale series Geochemistry Origin

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

波希米亚地块黑色页岩与其他地区...

国外地质（北京） 1992年第6期 43-46页

作者： pasava,j 贺连顺

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

黑色页岩中的金——IGCP研究新成果

黄金科技动态 1989年第9期 15-18页

作者： j.pasava 吴志勇捷克斯洛伐克地质调查局中国科学院兰州地质研究所

在世界许多地区富有机质陆源沉积型页岩中都发现了异常高含量的金,这种在沉积作用过程中形成的原生金可能来源于碎屑金或化学吸附金的聚集。尽管黑色页岩中的金含量与页岩中有机质的含量是正相关的,但是与有机质没有直接的联系,金颗粒... 详细信息

在世界许多地区富有机质陆源沉积型页岩中都发现了异常高含量的金,这种在沉积作用过程中形成的原生金可能来源于碎屑金或化学吸附金的聚集。尽管黑色页岩中的金含量与页岩中有机质的含量是正相关的,但是与有机质没有直接的联系,金颗粒依附在石英,铝硅酸盐矿物或黄铁矿等硫化物中。一、黑色页岩中金矿化类型和成因根据矿体中矿物的结构和形态特征。

关键词：黑色页岩金含量 IGCP研究

维普期刊数据库

Error field penetration in j-TEXT tokamak based on two-fluid drift-MHD model

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j-TEXT team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly jumps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

维普期刊数据库

Storing Freshwater Versus Storing Electricity in Power Systems with High Freshwater Electric Demand

在线全文

学校读者我要写书评

暂无评论

journal of Modern Power Systems and Clean Energy 2024年第2期12卷 323-333页

作者： Mubarak j.Al-Mubarak Antonio j.Conejo Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOHUSA Department of Electrical Engineering Kuwait UniversityP.O.Box 5969Safat 13060Kuwait Department of Integrated Systems Engineering and the Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOH 43210USA IEEE

We consider a power system whose electric demand pertaining to freshwater production is high(high freshwater electric demand),as in the Middle East,and investigate the tradeoff of storing freshwater in tanks versus storing electricity in batteries at the day-ahead operation *** storing freshwater and storing electricity increase the actual electric demand at valley hours and decrease it at peak hours,which is generally beneficial in term of cost and ***,to what extent?We analyze this question considering three power systems with different generation-mix configurations,i.e.,a thermal-dominated mix,a renewable-dominated one,and a fully renewable *** generation-mix configurations are inspired by how power systems may evolve in different countries in the Middle *** production uncertainty is compactly modeled using chance *** draw conclusions on how both storage facilities(freshwater and electricity)complement each other to render an optimal operation of the power system.

关键词： Power system operation freshwater production and transportation coordination day-ahead scheduling

维普期刊数据库

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

关键词：

Global weirding at mass extinction horizons

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2024年第1期11卷 10-12页

作者： Gregory j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

关键词：