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某些大陆拉斑玄武岩微量元素地球化学

地球与环境 1985年第6期 46-49+76页

作者： C.Dupuy j.dostal 梁晓中科院北京地质所

前言同大洋玄武岩相比,大陆拉斑玄武岩(CT)的特点是某些不相容元素的含量高,变化大,同位素比值的变化也大。大陆和大洋玄武岩的这种地球化学差异已讨论过多年,提出了几种不同的假说,以解释大陆拉斑玄武岩的这种地球化学特点。这些假说... 详细信息

前言同大洋玄武岩相比,大陆拉斑玄武岩(CT)的特点是某些不相容元素的含量高,变化大,同位素比值的变化也大。大陆和大洋玄武岩的这种地球化学差异已讨论过多年,提出了几种不同的假说,以解释大陆拉斑玄武岩的这种地球化学特点。这些假说包括:由“地幔羽”产生母岩浆;由不均匀富集的上地幔产生母岩

关键词：拉斑玄武岩相容元素岩石拉斑玄武质岩石地壳混染作用大陆地壳大陆型地壳地球化学地球科学微量元素痕量元素

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某些大陆拉斑玄武岩微量元素的地球化学

宝石和宝石学杂志(中英文) 1985年第2期 92-100页

作者： C.Dupuy j.dostal 李昌年

引言与大洋玄武岩相比,大陆拉斑玄武岩(CT)以具有高的且变化的不相容元素含量及变化的同位素比值为特征.大陆和大洋玄武岩之间的地球化学差异已讨论许多年了,并提出了几种假说来解释CT的地球化学特征,包括:地幔柱成因的母岩浆、不均一... 详细信息

引言与大洋玄武岩相比,大陆拉斑玄武岩(CT)以具有高的且变化的不相容元素含量及变化的同位素比值为特征.大陆和大洋玄武岩之间的地球化学差异已讨论许多年了,并提出了几种假说来解释CT的地球化学特征,包括:地幔柱成因的母岩浆、不均一的富集上地幔形成的母岩浆、地幔围岩反应、原生苦橄岩浆中榴辉岩的高压分离结晶及地壳混染作用.这些假说解释了CT成因的复杂性.

关键词：拉斑玄武岩大陆壳型式拉斑玄武质岩石地壳混染作用相容元素地球化学地球科学大陆地貌

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非洲西北部晚元古代安山岩中的金矿化

地质科技通报 1988年第2期 75-79页

作者： j.dostal C.Dupuy 曹新志

火山岩的变质作用常被人们公认是形成众多的金矿床的一个主要成矿作用(Boyle,1979)。但是,有关火山岩的背景含金量及金自围岩中活化迁移确切机制的数据资料却是非常缺乏的。本文的目的就是确定Hosggar(非洲西北部)晚元古代女山岩内金的... 详细信息

火山岩的变质作用常被人们公认是形成众多的金矿床的一个主要成矿作用(Boyle,1979)。但是,有关火山岩的背景含金量及金自围岩中活化迁移确切机制的数据资料却是非常缺乏的。本文的目的就是确定Hosggar(非洲西北部)晚元古代女山岩内金的背景值,评价低级变质作用对金在岩石中的分布的影响以及这种低级变质作用在金矿床的形成中所起的作用。

关键词：安山岩含金量化学成分化学组成岩石低级变质作用新元古代晚元古代非洲

基武南部(扎伊尔)与裂谷有关的火山岩的地球化学及岩石成因

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国外火山地质 1989年第1期 49-60页

作者： A.Auchapt C.Dupuy j.dostal M.Kanika 吴志勤

基武湖(Lake Kivu)南部(扎伊尔东南部)两个火山岩带是东非裂谷西支的一部分。两个火山岩带在三个火山旋回期间形成,这三个火山旋回一个是前裂谷阶段(70—7百万年)和两个同裂谷阶段(分别为7.0—1.9百万年和1.4万年一近期),并且火山岩带... 详细信息

基武湖(Lake Kivu)南部(扎伊尔东南部)两个火山岩带是东非裂谷西支的一部分。两个火山岩带在三个火山旋回期间形成,这三个火山旋回一个是前裂谷阶段(70—7百万年)和两个同裂谷阶段(分别为7.0—1.9百万年和1.4万年一近期),并且火山岩带从前裂谷阶段的石英拉斑玄武岩演化为裂谷阶段的碱性玄武岩。玄武质岩石数量占绝对优势,其成分接近于其它与裂谷有关的玄武岩及洋岛玄武岩。本区大多数玄武岩经历了十分有限的分离结晶(约5—10%),结晶矿物以橄榄石和单斜辉石为主。即使主要元素相近的岩石,其不相容元素也有明显变异,这暗示玄武质岩石来源于由于不同程度的熔融造成的不均匀源岩。推断的源岩成分与碱性玄武岩中交代橄榄岩捕虏体的成分十分接近。

关键词：裂谷玄武岩碧玄岩基性岩火山带火山岩带岩石刚果(金,利) 扎伊尔地球科学地球化学

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非洲西北部晚元古代火山岩中的铀和钍

世界核地质科学 1985年第3期 21-25页

作者： j.dostal C.Dupuy M.Chikhauoi M.Zentilli 周德安

非洲西北部晚元古代钙-碱性火山岩经受了低程度变质作用,其U和Th含量变化很大。英安岩和流纹岩的U、Th含量比基性岩要高些,尽管U、Th与SiO2的相关关系不明显,在酸性岩石中,U和Th与K的关系密切,而且基性和大多数中性熔岩中,这两种元素与... 详细信息

非洲西北部晚元古代钙-碱性火山岩经受了低程度变质作用,其U和Th含量变化很大。英安岩和流纹岩的U、Th含量比基性岩要高些,尽管U、Th与SiO2的相关关系不明显,在酸性岩石中,U和Th与K的关系密切,而且基性和大多数中性熔岩中,这两种元素与惰性的不相容的元素如Zr、Nb、La和Ce有相关关系。酸性火山岩与等量新鲜的近代岩石相比,其U和Th含量较低。如低U/K和Th/K比所示,在这些岩石中U和Th的减少也与K有关。U和Th的减少可能与次生作用有关,这表明非洲西北部的酸性火山岩可能是矿床中放射性元素富集的一个重要来源。

关键词：火山岩 Th 酸性喷出岩火成岩岩石放射性元素放射元素晚元古代新元古代非洲

Time evolution of stimulated Raman scattering and two-plasmon decay at laser intensities relevant for shock ignition in a hot plasma

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High Power Laser Science and Engineering 2019年第3期7卷 142-155页

作者： G.Cristoforetti L.Antonelli D.Mancelli S.Atzeni F.Baffigi F.Barbato D.Batani G.Boutoux F.D'Amato j.dostal R.Dudzak E.Filippov Y.j.Gu L.juha O.Klimo M.Krus S.Malko A.S.Martynenko Ph.Nicolai V.Ospina S.Pikuz O.Renner j.Santos V.T.Tikhonchuk j.Trela S.Viciani L.Volpe S.Weber L.A.Gizzi National Institute of Optics CNRPisa and FlorenceItaly York Plasma Physics Institute University of YorkHe slingtonYorkUK Universite de Bordeaux CNRSCEACELIATalenceFrance Donostia International Physics Center(DiPC) Donostia/San SebastianBasque CountrySpain Dipartimento SBAI Universita di Roma La SapienzaRomaItaly National Research Nuclear University MEPhl MoscowRussia CEA DAMDIFArpajonFrance Department of Radiation and Chemical Physics Institute of Physics of the CASPragueCzech Republic Laser Plasma Department Institute of Plasma Physics of the CASPragueCzech Republic joint Institute for High Temperature RAS MoscowRussia ELI-Beamlines Institute of Physics of the CASPragueCzech Republic FNSPE Czech Technical University in PraguePragueCzech Republic Universidad de Salamanca Ctr Laseres PulsadosSalamancaSpain Centro de Laseres Pulsados(CLPU) VillamayorSalamancaSpain

Laser–plasma interaction(LPI)at intensities 1015–1016 W·cm^-2 is dominated by parametric instabilities which can be responsible for a significant amount of non-collisional absorption and generate large fluxes of high-energy nonthermal *** a regime is of paramount importance for inertial confinement fusion(ICF)and in particular for the shock ignition *** this paper we report on an experiment carried out at the Prague Asterix Laser System(PALS)facility to investigate the extent and time history of stimulated Raman scattering(SRS)and two-plasmon decay(TPD)instabilities,driven by the interaction of an infrared laser pulse at an intensity^1.2×1016 W·cm^-2 with a^100μm scalelength plasma produced from irradiation of a flat plastic *** laser pulse duration(300 ps)and the high value of plasma temperature(~4 ke V)expected from hydrodynamic simulations make these results interesting for a deeper understanding of LPI in shock ignition *** results show that absolute TPD/SRS,driven at a quarter of the critical density,and convective SRS,driven at lower plasma densities,are well separated in time,with absolute instabilities driven at early times of interaction and convective backward SRS emerging at the laser peak and persisting all over the tail of the ***-scattering SRS,driven at low plasma densities,is also clearly *** results are compared to fully kinetic large-scale,two-dimensional ***-in-cell results,beyond reproducing the framework delineated by the experimental measurements,reveal the importance of filamentation instability in ruling the onset of SRS and stimulated Brillouin scattering instabilities and confirm the crucial role of collisionless absorption in the LPI energy balance.

关键词： plasma simulations shock ignition stimulated Raman scattering two-plasmon decay

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Surface Geophysical Methods used to Verify the Karst Geological Structure in the Built-up Area:A Case Study of Specific Engineering-Geological Conditions

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1763-1770页

作者： Rene PUTISKA Marian MARSCHALKO Isik YILMAZ Dominik NIEMIEC CHENG Xianfeng Ivan dostal jan KUBAC Comenius University Faculty of Natural SciencesDepartment of Applied and Environmental GeophysicsIlkovičova 6BratislavaSlovakia VSB-Technical University of Ostrava Faculty of Mining and GeologyInstitute of Geological Engineering17 listopadu1570833OstravaCzech Republic Cumhuriyet University Faculty of EngineeringDepartment of Geological Engineering58140 SivasTurkey Yunnan Land and Resources Vocational College Kunming 652501China

This article presents a research study of complex limestone karst engineering-geological conditions in the municipality Valaskanear Banska Bystrica in *** aim of the study is to demonstrate the impossibility of spatial identification of cave spaces using surface geophysical methods due to the specific engineering-geological conditions of a thick surface layer of anthropogenic fill containing highly heterogeneous anthropogenic *** maximum thickness is 3 *** specificific condition of the study area is its location in the built-up area,due to which the applicability of geophysical methods was *** article contains methodological recommendations to be used in analogous geological conditions with karst structures topped with anthropogenic fill,which complicates the identification of cave *** recommended solution herein is the identification of the cave system using underground mapping of the karst and its projection onto the surface for which surface geophysical methods have been combined.

关键词： karst engineering geology limestone dolomite anthropogenic fill complicated engineering-geological conditions geophysical study

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A detailed reconstruction of changes in the factors and parameters of soil erosion over the past 250 years in the forest zone of European Russia(Moscow region)

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International Soil and Water Conservation Research 2022年第1期10卷 149-160页

作者： Andrey Zhidkin Daria Fomicheva Nadezhda Ivanova Tomas dostal Alla Yurova Mikhail Komissarov josef Krasa V.V.dokuchaev soil science institute pyzhevskiy pereulok 7moscow119017russian federation Faculty of geography lomonosov moscow state universityleninskie gorygsp-1moscow119991russian federation Department of landscape water conservation faculty of civil engineeringczech technical university in praguethakurova 7prague16629czech republic Ufa institute of biology ufrc russian academy of sciencespr.oktyabrya 69ufa450054russian federation

Accelerated soil erosion is a major threat to soil,and there are great variations in the rate of soil erosion over time due to natural and human-induced *** temperate forest zone of Russia is character-ized by complex stages of land-use history(*** urbanization,agricultural development,land abandonment,etc.).We have for the first time estimated the rates of soil erosion by the WaTEM/SEDEM model(rainfall erosion)and by a regional model(snowmelt erosion)over the past 250 years(from 1780 to 2019)for a 100-km2 study site in the Moscow region of *** calculations were made on the basis of a detailed historical reconstruction of the following factors:the location of the arable land,crop rotation,the rain erosivity factor,and the maximum snow water *** area of arable land has decreased more than 3.5-fold over the past 250 *** the end of the 20th century,the rates of gross erosion had declined more than 5.5-fold(from 28×10^(3) to 5×10^(3) t·ha^(-1)yr^(-1))in comparison with the end of the 18th *** in the boundaries of arable land and also the relief features had led to a significant intra-slope accumulation of *** a result of sediment redeposition within the arable land,the variation in net soil erosion was significantly lower than the variation in gross soil *** changes in arable land area and in crop composition are the factors that have to the greatest extent determined the changes in soil erosion in this territory.

关键词： Anthropogenic soil erosion Soil erosion history Crop rotation Magnetic tracer method WaTEM/SEDEM

汽车电子技术走向系列3 具备高效休眠模式的车用开关DC-DC稳压器

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电子与电脑 2008年第4期8卷 83-85页

作者： Frederik dostal 美国国家半导体

即使是在车辆停泊或者暂停开动时,许多车用配备必须持续保持在待命执行状态。像是保存记忆内容的内存、持续运转的时钟,以及不断运行的车用传感器等系统。这些装置在"休眠"状态下只需要很少的耗电。而汽车制造商在设计时必须做出最大耗... 详细信息

即使是在车辆停泊或者暂停开动时,许多车用配备必须持续保持在待命执行状态。像是保存记忆内容的内存、持续运转的时钟,以及不断运行的车用传感器等系统。这些装置在"休眠"状态下只需要很少的耗电。而汽车制造商在设计时必须做出最大耗电预估,,5V状态下的150μA电流必须包括实际负载以及12V车载电池电压转换损耗。这将确保在汽车长时间停泊情形下,电池电量不会被耗尽。为了减少特定应用的组件数量和降低成本,可采用一个在低输出负荷模式(休眠模式)下具有高效率,又同时能为系统正常操作供电的电源。本文将提出车用系统使用的应用解决方案,列举达到高效休眠模式的不同方法,并说明怎样有效测量效率,以及效率测量对静态电流和对整个耗电预算的重要性。本文列举了启动接脚的问题实例:根据实现方式的不同,在开启或关闭状态,将会有一些电流消耗。

关键词：车用传感器休眠模式汽车电子技术 DC-DC 稳压器开关测量效率静态电流

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