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缺氧沉积岩——PGE富集的重要环境

国外铀金地质 1994年第4期11卷 326-333页

作者： j.paava 刘家军成都理工学院地化教研室 610059

近几年来,缺氧沉积岩和变质岩已作为铂族元素(Platinum Group Elements,PGE)富集的容矿环境。在许多文章中报道了中国、加拿大和波兰海相富金属黑色页岩中PGE的大量工业富集,含矿层厚度很薄,但有时在横向上分布很广,与陆内裂谷的构造演... 详细信息

近几年来,缺氧沉积岩和变质岩已作为铂族元素(Platinum Group Elements,PGE)富集的容矿环境。在许多文章中报道了中国、加拿大和波兰海相富金属黑色页岩中PGE的大量工业富集,含矿层厚度很薄,但有时在横向上分布很广,与陆内裂谷的构造演化有联系,但无任何岩浆活动。根据分析,作者提出了PGE的复杂组合形式。研究表明,缺氧沉积岩中的PGE富集特征与其他热液PGE矿床的特征具有很多共同点。然而,捷克和芬兰两地产于火山裂谷中的海相富金属黑色页岩中的PGE含量较低,矿化层厚度大,但水平延伸不远,表明其与火山活动中心有密切联系。低Ni/Cu比值和(PGE+Au)的球粒陨石标准化模式与某些镁铁质、超镁铁质岩中的岩浆PGE矿床类似。在裂谷和火山裂谷中,有机质对富金属黑色页岩中PGE的富集起了很重要的作用。

关键词：缺氧环境碳质岩石铂族元素矿床沉积岩

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重构现场:新闻报道的空间叙事策略

四川大学学报（哲学社会科学版） 2011年第3期 42-48页

作者：操慧四川大学文学与新闻学院四川成都610064

新闻报道的空间建构是新闻报道有效叙事之重点环节,聚焦于现场的报道,是一种立足于深刻认知新闻现场和现场新闻之内在关联的选择性重构,现场既代表新闻报道的语境与情境还原,同时也是实现传受双方互动理解的一种审美超越。现场的报道空... 详细信息

新闻报道的空间建构是新闻报道有效叙事之重点环节,聚焦于现场的报道,是一种立足于深刻认知新闻现场和现场新闻之内在关联的选择性重构,现场既代表新闻报道的语境与情境还原,同时也是实现传受双方互动理解的一种审美超越。现场的报道空间建构不仅体现出新闻报道的时效要求对叙事策略选择的必然,更通过叙事设计的结构化、进入化策略来实践传受双方知觉场的共建,尤其在当代新媒体环境下,新闻报道的空间叙事策略将伴随社会空间的心灵感知而不断创新发展。重视并有效发掘、应用那些能够激发受众感知的想象力的空间要素,才是新闻报道未来创新的方向,空间的重构也绝非是媒介技术提供的拟态逼真,而是构建合乎受众认知需求与审美体验的空间实践,是叙事的社会参与,也是其心灵对话空间的共建。

关键词：新闻现场现场新闻空间叙事策略

The supernova remnant CTB 37B and its associated magnetar CXOU j171405.7-381031:evidence for a magnetar-driven remnant

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Research in Astronomy and Astrophysics 2011年第6期11卷 625-630页

作者： j.E.Horvath M.P.Allen Instituto de Astronomia Geofísica e Ciências Atmosféricas-Universidade de So PauloRua do Mato122605508-900 Cidade Universitria So Paulo SPBrazil CEFET So paulo Rua Pedro Vicente 62501109-010Caninde'So Paulo SPBrazil

We discuss the association between the candidate magnetar CXOU j171405.7-381031 and the supernova remnant CTB *** recent detection of the period derivative of the object allowed an estimation of a young characteristic age of only ～ *** value is too small to be compatible even with the minimum radius of the remnant being ≥ 10 pc,the value corresponding to the lower limit of the estimated distance of 10.2 ± 3.5 kpc,unless the true distance happens to be even smaller than the lower *** argue that a consistent scenario for the remnant＇s origin,in which the latter is powered by the energy injected by a young magnetar,is indeed more accurate to explain the young age,and demonstrates its non-standard（***-driven） nature.

关键词： stars:supernova — stars:neutron

Safe mining practices under wide spans in underground non-caving mines——case studies

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International journal of Mining Science and Technology 2019年第4期29卷 535-540页

作者： j.j.Ran Kinross Gold Corporation

Mining under wide span is of concern as it increases the probability of back caving causing personnel injury and equipment damage in underground mines in open stoping and underhand drift-and-fill *** restricting personnel access to well supported lateral development is commonly practiced,it is not always possible to implement this requirement due to various factors such as ore loss control,drilling equipment limitations,availability of remote operating capacity and consideration of *** with rules implemented to limit personnel entry into openings with wide spans,the hazards of equipment damage and back caving still *** the years,different practices have been reported and adopted to minimize risks associated with exposure to large spans in various underground *** from these practices are beneficial to current and future mines with challenges of safe extraction of thick deposits in a non-caving *** paper briefly summarizes practices in mining wide orebodies using the open stoping method without personnel access and underhand mining using the drift-andfill method with personnel exposure in the industry and presents cases from Kinross mines where the hanging pillar design was tested,and stope backs were naturally and artificially supported for extraction under wide spans using the open stoping method.

关键词： Mine safety Wide span Back stability Underhand mining Hanging pillar

Numerical Determination of Stress Fields of and Forces on Line Dislocations in Anisotropic Multilayer Structures

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电子显微学报 1997年第4期 183-184页

作者： Marun j.Abbudi \ L.Y.pang\ David M.Barnett (Division of Applied Mechanics, Department of Mechanical Engineering, Stanford University, Stanford, ca 94305 4040, USA)

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关键词： Stress Fields Determination

A Study on Solid/Melt Interfaces and the Formation of<100> Texture in Solidified FCC Metals

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journal of Materials Science & Technology 1997年第6期13卷 457-461页

作者： D.Y.Li(Dept. of Mater. Sci & Eng., The Pennsylvania State University, University park, pa 16802, USA )B.Debray and j.A.Szpunar(Dept. of Metall. Eng., McGill University, 3450 Uuiversity Street, Molitreal, PQ, canada H3A 2A7) Dept. of Mater. Sci and Eng. Pennsylvania State University University Park PA 16802 United States Dept. of Metall. Eng. McGill University Montreal PQ H3A 2A7 3450 University Street Canada

The (100) texture of solidified fcc metals, caused by the preferential (100) dendrite growth, could be closeIy related to solid/melt interfaces which behave differently along different crystallographic orientation. The stability and roughness of {111} and {100} solid/melt interfaces of fcc metals were investigated using a modified Temkin multi-layer model. It is demonstrated that {100}crystal/melt interface is more unstable and rougher than {111} interface. The effect of the stability of crystal/melt interface on the (100) texture formation in solidified fcc metals has been analysed and discussed.

关键词： FCC A Study on Solid/Melt Interfaces and the Formation of<100 Texture in Solidified FCC Metals

Geochemistry and mineralogy of platinum-group elements(PGE)in chromites from CentralnoyeⅠ,Polar Urals,Russia

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Geoscience Frontiers 2011年第1期2卷 81-85页

作者： jan paava Ilja Knésl Anna Vymazalová Ivan Vavrín Ludmila Ivanovna Gurskaya Leonid Ruslanovich Kolbantsev Czech Geological Survey Geologicka 6152 00 Praha 5Czech Republic All Russia Geological Research Institute(VSEGEI) 74 Srechy Pr.199 106 St.PetersburgRussia

The Polar Urals region of northern Russia is well known for large chromium （Cr）-bearing massifs with major chromite orebodies, including the Centralnoye I deposit in the Ray-Iz ultramafic massif of the Ural ophiolite belt. New data on platinum （Pt）-group elements （PGE）, geochemistry and mineralogy of the host dunite shows that the deposit has anomalous iridium （Ir） values. These values indicate the predominance of ruthenium--osmium--iridium （Ru--Os--Ir）-bearing phases among the platinum-group mineral （PGM） assemblage that is typical of mantle-hosted chromite ores. Low Pt values in chromites and increased Pt values in host dunites might reflect the presence of cumulus PGM grains. The most abundant PGM found in the chromite is erlichmanite （up to 15 μm）. Less common are cuproiridsite （up to 5 μm）, irarsite （up to 4--5 μm）, and laurite （up to 4 μm）. The predominant sulfide is heazlewoodite, in intergrowth with Ni--Fe alloys, sporadically with pentlandite, and rarely with pure nickel. Based on the average PGE values and esti- mated Cr-ore resources, the Centralnoye I deposit can be considered as an important resource of PGE.

关键词： Platinum-group elements Platinum-group minerals Chromite Ophiolites Centralnoye I deposit Polar Urals

Gas Line Pressure Fluctuation Analysis of a Gas-Liquid Reactor

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journal of Thermal Science 2005年第3期14卷 267-271页

作者： j.j.j. CHEN j.C. ZHAO Chemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand ProfessorChemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand

To ensure efficient operation of metallurgical gas-liquid reactors, the gas bubbles must be uniformly distributed. For high temperature metallurgical reactors, it is impractical and unsafe to carry out visual observations. An air-water model was used to study the relationship between the bubble flow patterns and the pressure fluctuation signals. The fluctuation signals captured in the time domain were transformed into the frequency domain. Various parameters obtained from the transformed data were analysed for their suitability for delineating the bubble flow patterns observed. These parameters and the flow patterns were found to be well-correlated using the gas flow number.

关键词： gas liquid reactors bubble distribution signal analysis

Computational study on influence of RF shielding box on inductance of coil

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Plasma Science and Technology 2019年第6期21卷 23-28页

作者： S j KIM j j LEE Y S LEE j H KIM S j YOU Applied Physics lab for PLasma Engineering(APPLE) Department of Physics Chungnam National University Daejeon 34134 Republic of Korea Korea Research Institute of Standards and Science(KRISS) Daejeon 34113 Republic of Korea

Despite the fact that a radio frequency (RF) shielding box affects a coil inductance used in matching network,RF engineers have used a coil inductance measured in open space on designing matching networks since it is difficult to precisely measure the coil inductance within the RF shielding *** this work,we investigate the influences of the RF shielding box on the coil inductance via a 3D full electromagnetic wave *** results shows that the coil inductance decreases from-6.0% to-11.9% compared with its ideal inductance depending on coil positions within the RF shielding *** inductive and capacitive coupling between the coil and surfaces of the RF shielding box contribute to the reduction of the coil *** expect that these results would be useful for those who design RF matching networks.

关键词： 3D full EM wave simulation RF matching component RF shield inductive and capacitive coupling