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Experimental Study on the Leaching of Gold from Greenstone

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Acta Geologica Sinica(English Edition) 1993年第2期67卷 211-221页

作者： Liu Yushan, Zhang Guilan institute of Mineral Deposits, chinese {2. of Geological {3., Beijing and Tian Jun Changchun College of Geology, Changchun, Jilin institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

Experiments were conducted on the leaching of gold from greenstone by chloride solution under the temperature of 2.0—550℃ and the pressure of 60 MPa. During part of the experiments, the oxygen fugacity was controlled. The results show that the leaching rate of gold is related to temperature, composition of the solution, pH and oxygen fugacity. In the experiment with oxidative acidic solution, the leaching rate was up to 50％ or more. It is known that the leaching of gold is restricted by the reaction in which the gold is dissolved from the rock to form gold chloride complex. Therefore, the authors hold that the acidic chloride solution derived from granite magma has caused the remobilization-migration of gold from greenstone and its enrichment into ore.

关键词： leaching gold deposits greenstone

Planar cubic hybrid hyperbolic polynomial curve and its shape classification

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Progress in Natural Science:Materials International 2004年第1期14卷 42-47页

作者： WANG Guozhao 1,2. * and YANG Qinmin 1,2. (1. institute of Computer Graphics and Image Processing, 2. Department of Mathematics, Zhejiang University, Hangzhou 3.002., china) Zhejiang Univ Inst Comp Graph & Image Proc Hangzhou 310027 Peoples R China Zhejiang Univ Dept Math Hangzhou 310027 Peoples R China

The planar cubic hybrid hyperbolic polynomial curves and cubic H Bézier curves are presented. The conditions leading to inflection points and singularities (cusps and loops) are investigated and the shape of these curves is classified. The conclusions enable us to detect inflection points and singularities and get an idea of how to preserve the fair shape when designing such curves.

关键词： hybrid hyperbolic polynomial curve H-Bézier curve shape classification inflection points singularities

Improvement of refrigerant capacity of La_(0.67)Ca_(0.3.)MnO_(3. single crystal with a few percent Fe doping

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Science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 809-812页

作者： LI GuoKe, ZHANG XiangQun, KOU ZhiQi, LI QingAn, SUN Young & CHENG ZhaoHua State Key Laboratory of Magnetism, Beijing National Laboratory of Condensed Matter Physics and institute of Physics, chinese academy of sciences, Beijing 100190,{2. State Key Laboratory of Magnetism Beijing National Laboratory of Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing China

Large low-field-induced magnetic entropy changes, ΔSM, are observed in La0.67Ca0.3.MnO3.and La0.67-Ca0.3.Mn0.96Fe0.04O3.single crystals. The peaks of ΔSM broadened asymmetrically to high temperatures under higher magnetic fields for two materials should be attributed to the first-order magnetic phase transition at Tc. A small amount of iron doping results in an increase in the refrigerant capacity of the material though the magnetic entropy change decreases. The discovery of excellent magnetocaloric features of these single crystals in the low magnetic field can provide some ideas for exploring novel magnetic refrigerants operating under permanent magnet rather than superconducting one as magnetic field source.

关键词： single crystal magnetic entropy refrigerant capacity

INTRODUCTION OF NEW ANTICORROSIVE DESIGN FOR REACTORS EXPOSED TO HIGH TEMPERATURE AND HIGH PRESSURE HYDROGEN

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 932-935页

作者： J.L. Li 1,2. , K.F. Wong 3. and G.H. Zhu 3. 1) Fushun Petroleum institute,Fushun 113.01,china 2. State Key Laboratory for Corrosion and Protection of Metal,institute of Corrosion and Protection of Metals, The chinese academy of sciences,S

This paper integrates the characteristic of structure design and manufacture and maintenance for chinese flat steel band wound pressure vessel(UCWPV) with the problems existing in current in service high temperature and pressure vessel exposed to hydrogen. In view of economy and safety it is suggested that it be practicable for UCWPV to act as reactors for platreating, hydrogenating, and catforming. UCWPV has not only potential advantages, but also removes shortages present in in-service reactors for hydrogen.

关键词： design pressure vessel hydrogen attack

Sensitivity of soils to acid rain in South china

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Journal of Environmental sciences 1990年第1期2卷 49-53页

作者： Huang Runhua, Yang Rong and Cao Hongfa1Peking University,Beijing 100871,china2.eijing institute of Environmental Protection,Beijing 10003.,china. 3.4} research academy of Environment Science,Beijing 100012.china.

This paper deals with the sensitivity of soils to acid rain in 5 provinces, South china. Based on field work and literature, and taking soil pH, CEC, and the types of residua into account, the authors classified the sensitivity into 4 categories: highly sensitive, sensitive, slightly sensitive, and non-sensitive. By overlapping the maps of soil pH, CEC, and types of residua, the map of soil sensitivity in South china has finally *** authors try to summarize the regularity of soil sensitivity to acid rain in this area. The sensitivity of different soil types in the studied area has also *** seriousness and its prospects of acid rain in this area have been pointed out in order to draw the attention of relevant authorities.

关键词： acid rain sensitivity of soils soil buffer capacity South china.

中国大陆地壳“镶嵌与叠覆”的结构特征及其演化

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地质通报 2004年第9期23卷 986-1004页

作者： LI Jinyi(institute of Geology, chinese {2. of Geological {3., Beijing 10003., china) 中国地质科学院地质研究所北京10003.

初步探讨了中国大陆地壳“块带镶嵌多层叠覆”的结构特征和多阶段的构造演化过程。中国大陆地壳新元古代中期以来的一级构造单元有中朝、塔里木、扬子、敦煌4个陆块和中央、西北、东北、西南、东南5个造山区(带)。中朝陆块的形成源于古... 详细信息

初步探讨了中国大陆地壳“块带镶嵌多层叠覆”的结构特征和多阶段的构造演化过程。中国大陆地壳新元古代中期以来的一级构造单元有中朝、塔里木、扬子、敦煌4个陆块和中央、西北、东北、西南、东南5个造山区(带)。中朝陆块的形成源于古元古代期间发生的古大陆裂解;扬子、塔里木和敦煌陆块的形成源于新元古代早期发生的古大陆裂解。西北造山区的形成源于古生代晚期洋盆关闭、大陆碰撞并叠加新生代陆内再造山;东北造山带的形成过程包括古生代碰撞造山及中生代增生、碰撞造山;中央造山带至三叠纪大陆碰撞才最后形成并叠加有新生代再造山;东南造山带的形成经历了古生代至新生代的多次造山作用;西南造山带主要是中—新生代造山作用的产物。这些单元都具有“块带镶嵌多层叠覆”的结构特征和多阶段构造演化的特点。中国大陆地壳的形成与演化可以划分为太古宙—古元古代、中元古代—新元古代早期、新元古代中期—古新世和始新世以来4个构造阶段,每个阶段都对应不同的超大陆裂解-聚合旋回。其中新元古代中期以来的地壳形成演化与全球洋陆格局中的古亚洲洋、古特提斯洋、古太平洋、特提斯洋和太平洋5个动力学体制有关,相应地可以归结为古亚洲、古特提斯、古太平洋、特提斯和太平洋5个造山域。

关键词：中国大陆地壳块带镶嵌多层叠覆超大陆裂解-聚合旋回动力学体制造山域

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基于LAN的语音通讯软件设计

计算机工程与应用 2003年第4期39卷 137-138,177页

作者：李宁溪张峡中国科学院近代物理研究所兰州730000

文章介绍了网络语音通信的原理、关键技术和实现方法,详细叙述了基于LAN的语音通信软件的开发过程,给出了相应的实例。该软件在音质和时延上都达到了IP电话的效果。

关键词：软件设计语音通讯软件 LAN IP电话通话服务质量网络音频传输

Technical development of proteomics

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chinese Science Bulletin 1999年第16期44卷 1441-1447页

作者： WAN Jinghong and HE Fuchu1.Chongqing Medical University, Chongqing 400046, china 2. Beijing institute of Radiation Medicine, Beijing 100850, china Corresponding author Chongqing Medical University Chongqing China Beijing institute of Radiation Medicine Beijing China

Proteome research is an important complementarity for the genome research, which uses quantitative protein-level measurements to characterize biological process. Proteome techniques include two aspects. One is two-dimensional electrophoresis, which is the unique technology to separate the components of proteome. The other is identification of the

关键词： proteome two-dimensional electrophoresis image analysis peptide-mass fingerprinting database.

Relationship Between Water-Stable Aggregates and Nutrients in Black Soils After Reclamation

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Pedosphere 2007年第4期17卷 538-544页

作者： MA Qiang YU Wan-Tai ZHAO Shao-Hua ZHANG Lu institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）.

Water-stable aggregates, which are an index for the evaluation of the structural properties of the soil, are affected by many factors. Zhaoguang Farm, Longzhen Farm, and Jiusan Farm were chosen as the representative study sites in the region of black soils, a typical soil resource in Northeast china. The variation in the content of 〉 0.2. mm water-stable aggregates and its relationship with the nutrients in black soil were investigated after different years of reclamation. The results showed that the 〉 0.2. mm water-stable aggregates were more in the surface than in the subsurface soil and they changed in the following order： Longzhen Farm 〉 Zhaoguang Farm 〉 Jiusan Farm. The water-stable aggregates decreased sharply at the initial stage of reclamation and then became stable gradually with time. They were significantly correlated with the contents of organic C, total N, total P, and CEC in black soil, with the correlation coefficients r being 0.76, 0.68, 0.61, and 0.81 （P 〈 0.01）, respectively; however, their relationships with available P, available K, and total K were unclear. These showed that organic matter was the cementation of soil water-stable aggregates. Increasing decompositions and decreasing inputs of organic matter after reclamation were responsible for the amount of reduction of the water-stable aggregates. Thus, to maintain good soil aggregate structure, attention should be paid to improvement of soil nutrient status, especially the supply of organic C and N.

关键词： black soils nutrients reclamation water-stable aggregates