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REE and C-O Isotopic Geochemistry of Calcites from the World-class Huize Pb-Zn Deposits,Yunnan,China:Implications for the Ore Genesis

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Acta Geologica Sinica(English Edition) 2010年第3期84卷 597-613页

作者： HUANG Zhilong li xiaobiao ZHOU Meifu li Wenbo JIN Zhongguo State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry the Chinese Academy of Sciences Guiyang 550002 China Department of Earth Sciences University ofHong Kong Hong Kong China Graduate School the Chinese Academy of Sciences Beijing 100039 China MOE Key Laboratory of Orogenic Belts and Crustal Evolution Peking University Beijing 100871 China

The world-class Huize Pb-Zn deposits of Yunnan province,in southwestern China,located in the center of the Sichuan-Yunnan-Guizhou Pb-Zn polymetallic metallogenic province,has Pb＋Zn reserves of more than 5 million tons at Pb＋Zn grade of higher than 25%and contains abundant associated metals,such as Ag,Ge,Cd,and *** deposits are hosted in the Lower Carboniferous carbonate strata and the Permian Emeishan basalts which distributed in the northern and southwestern parts of the *** is the only gangue mineral in the primary ores of the deposits and can be classified into three types,namely lumpy,patch and vein calcites in accordance with their *** is not intercalated contact between calcite and ore minerals and among the three types of calcite,indicating that they are the same ore-forming age with different stages and its forming sequence is from lumpy to patch to vein calcites. This paper presents the rare earth element（REE） and C-O isotopic compositions of calcites in the Huize Pb-Zn *** lumpy to patch to vein calcites,REE contents decrease as LREE/ HREE ratios *** chondrite-normalized REE patterns of the three types of calcites are characterized by LREE-rich shaped,in which the lumpy calcite shows（La）_N〈（Ce）_N〈（Pr）_N≈（Nd）_N with Eu/Eu~＊〈1,the patch calcite has（La）_N〈（Ce）_N〈（Pr）_N≈（Nd）_N with Eu/Eu~＊〉1,and the vein calcite displays（La）_N〉（Ce）_N〉（Pr）_N〉（Nd）_N with Eu/Eu~＊〉*** REE geochemistry of the three types of calcite is different from those of the strata of various age and Permian Emeishan basalt exposed in the ***δ^（13） C_（PDb） andδ^（18）O_（Smow） values of the three types of calcites vary from-3.5‰to-2.1‰and 16.7‰to 18.6‰,respectively,falling within a small field between primary mantle and marine carbonate in theδ^（13）C_（PDb） vsδ^（18）O_（Smow） diagram. Various lines of evidence demonstrate that the three types of calcites in the deposits are produced from the same source with different *** ore-forming f

关键词： gangue calcite REE geochemistry C-O isotope ore-forming fluid Huize Pb-Zn deposits

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Trace Elements and Rare Earth Elements of Sulfide Minerals in the Tianqiao Pb-Zn Ore Deposit,Guizhou Province,China

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Acta Geologica Sinica(English Edition) 2011年第1期85卷 189-199页

作者： ZHOU Jiaxi HUANG Zhilong ZHOU Guofu li xiaobiao DING Wei BAO Guangping State Key Laboratory of Ore Deposits Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Trace elements and rare earth elements（REE） of the sulfide minerals were determined by inductively-coupled plasma mass *** results indicate that V,Cu,Sn,Ga,Cd,In,and Se are concentrated in sphalerite,Sb,As,Ge,and Tl are concentrated in galena,and almost all trace elements in pyrite are *** Ga and Cd contents in the light-yellow sphalerites are higher than that in the brown and the black *** contents of Ge,Tl,In,and Se in brown sphalerites are higher than that in light-yellow sphalerites and black *** shows that REE concentrations are higher in pyrite than in sphalerite,and *** sphalerites,the REE concentration decreases from light-yellow sphalerites,brown sphalerites,to black *** ratios of Ga/In are more than 10, and Co/Ni are less than 1 in the studied sphalerites and pyrites,respectively,indicating that the genesis of the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis associated with hydrothermal *** relationship between LnGa and LnIn in sphalerite,and between LnBi and LnSb in galena,indicates that the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed *** on the chondrite-normalized REE patterns,δEu is a negative anomaly（0.13-0.88）,andδCe does not show obvious anomaly（0.88-1.31）;all the samples have low total REE concentrations（〈3 ppm） and a wide range of light rare earth element/high rare earth element ratios（1.12-12.35）.These results indicate that the ore-forming fluids occur under a reducing *** REE compositions and parameters of sphalerites,galenas,pyrites,ores,altered dolostone rocks,strata carbonates,and the pyrite from Lower Carboniferous Datang Formation showed that the ore-forming fluids might come from polycomponent systems,that is,different chronostratigraphic units could make an important contribution to the ore-forming *** with the tectonic setting and previous isotopic geochemistry evidence,we conclude that

关键词： trace element rare earth element sphalerite galena pyrite deposit genesis Tianqiao PbZn ore deposit

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Sulfur isotopic composition of the Tianqiao Pb-Zn ore deposit,Northwest Guizhou Province,China:Implications for the source of sulfur in the ore-forming fluids

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Chinese Journal Of Geochemistry 2010年第3期29卷 301-306页

作者： ZHOU Jiaxi HUANG Zhilong ZHOU Guofu li xiaobiao DING Wei BAO Guangping The State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China The Graduate University Chinese Academy of Seiences Beijing 100049 China

The Tianqiao Pb-Zn ore deposit of Guizhou Province, China, is located in the mid-east of the Sichuan-Yunnan-Guizhou Pb-Zn-Ag multi-metallic mineralization area, which is representative of the Pb-Zn ore de-posits in this area. It consists of three main orebodies, whose Pb+Zn reserves are more than 0.2 million ton. This paper analyzes the sulfur isotopic composition of these orebodies. The data show that the ore minerals (galena, sphalerite, pyrite) in these orebodies are enriched in heavy sulfur, with δ34SV-CDT values varying between 8.35‰ and 14.44‰, i.e. the δ34SV-CDT values of pyrite are between 12.81‰ and 14.44‰, the mean value is 13.40‰; the δ34SV-CDT values of sphalerite are range from 10.87‰ to 14.00‰, the mean value is 12.53‰; the δ34SV-CDT values of galena are range from 8.35‰ to 9.83‰, the mean value is 8.84‰, and they have the feature of δ34Spyrite>δ34Ssphalerite>δ34Sgalena, which indicates the sulfur isotope in ore-forming fluids has attained equilibrium. The δ34S V-CDT values of the deposit are close to those of sulfates from carbonate strata of different ages in the ore-field (15‰), which suggests that the sulfur in the ore-forming fluids should be derived from the thermo-chemical sulfate reduction of sulfates from the sedimentary strata.

关键词：硫同位素组成成矿流体来源铅锌矿贵州省天桥中国西北部硫酸盐还原

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整体叶盘柔性磨头自适应抛光实现方法

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航空学报 2011年第5期32卷 934-940页

作者：段继豪史耀耀李小彪张军锋西北工业大学现代设计与集成制造技术教育部重点实验室陕西西安710072

基于整体叶盘使用性能和寿命影响因素分析,以整体叶盘结构与材料特性为依据,结合整体叶盘人工抛光工艺方法,提出了适合整体叶盘表面抛光的自适应柔性磨头实现方案。对实现柔性磨头工作原理和自适应区域进行了分析计算,并对其控制技术进... 详细信息

基于整体叶盘使用性能和寿命影响因素分析,以整体叶盘结构与材料特性为依据,结合整体叶盘人工抛光工艺方法,提出了适合整体叶盘表面抛光的自适应柔性磨头实现方案。对实现柔性磨头工作原理和自适应区域进行了分析计算,并对其控制技术进行了研究,对柔性抛光方法可行性进行验证,最终实现了整体叶盘自适应柔性抛光。初步抛光实验表明,较之人工抛光方法,柔性磨头自动抛光效率提高50%以上,显著缩短了整体叶盘生产周期,抛光后表面粗糙度达到Ra0.4以内,满足表面一致性、稳定性、型面质量等要求,并且可以减小劳动强度,降低生产成本。

关键词：整体叶盘抛光自适应柔性磨头航空发动机

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文化资本对旅游经济增长的结构性影响

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管理世界 2018年第11期34卷 184-185页

作者：李晓标解程姬内蒙古财经大学旅游学院北京大学城市与环境学院旅游研究与规划中心内蒙古建筑职业技术学院

本文在对文化资本进行分类的基础上分析了其对于中国旅游经济增长影响的结构性差异。研究发现文化产业和文化遗产对于旅游经济的促进作用最明显,但是文化产业的促进作用既可以通过促进物质资本积累来实现,也可以通过促进人力资本积累来... 详细信息

本文在对文化资本进行分类的基础上分析了其对于中国旅游经济增长影响的结构性差异。研究发现文化产业和文化遗产对于旅游经济的促进作用最明显,但是文化产业的促进作用既可以通过促进物质资本积累来实现,也可以通过促进人力资本积累来实现,而文化遗产的促进作用则主要通过影响物质资本的积累来实现。与之相反,文化体制对于旅游经济增长的影响是不明显的,这主要是因为现行的文化体制虽然能够促进物质资本积累,但是却不利于人力资本的积累,而且还在一定程度上直接挤出了旅游收入的提高。

关键词：文化资本旅游经济结构性影响

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航空发动机叶片柔性抛光技术

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航空学报 2012年第3期33卷 573-578页

作者：段继豪史耀耀张军锋董婷李小彪西北工业大学现代设计与集成制造技术教育部重点实验室陕西西安710072

基于发动机叶片结构特点及其抛光工艺要求,为实现叶片型面及阻尼台自动化抛光,满足其型面及进排气边尺寸、粗糙度等质量要求,消除叶片型面波纹对抛光工艺的影响,对砂带柔性抛光工艺装备技术进行研究,提出基于抛光力控制的砂带柔性磨头... 详细信息

基于发动机叶片结构特点及其抛光工艺要求,为实现叶片型面及阻尼台自动化抛光,满足其型面及进排气边尺寸、粗糙度等质量要求,消除叶片型面波纹对抛光工艺的影响,对砂带柔性抛光工艺装备技术进行研究,提出基于抛光力控制的砂带柔性磨头抛光工艺方法,并对其抛光工艺过程、抛光力控制进行研究,通过对叶片自动化抛光编程及抛光轨迹路径规划技术研究,最终实现发动机叶片高效柔性抛光工艺。抛光试验结果表明,柔性自动化抛光后叶片型面尺寸精度可达±0.06mm,粗糙度低于Ra0.4,与传统手工抛光方法相比,大大提高其抛光效率及表面质量稳定性,降低劳动强度,且减少粉尘污染。

关键词：发动机叶片柔性抛光工艺砂带自动化

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Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

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Science China(Technological Sciences) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2, WANG Shijie2, FENG Junming2, li Chunlai1, OUYANG Ziyuan1,2, liU Jianzhong1 & li xiaobiao2 1. National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China 2. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China National Astronomical Observatories Chinese Academy of Sciences Beijing China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2+Fe2O4 and Fe2O3 type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 10.0, μ ′ = 1.2-1.5, μ ″ = 1.0-1.2, respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

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内河限制性航道船舶下沉量研究

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中国科技论文 2021年第8期16卷 902-905,918页

作者：缪吉伦吴俊李晓飙重庆交通大学西南水运工程科学研究所重庆400016 重庆西科水运工程咨询中心重庆400016

为了研究内河限制性航道中船舶航行下沉量,建立了室内概化物理模型,开展试验研究。模拟测试了1000~3000 t级船舶在不同渠道宽度、水深及航速条件下船舶航行的下沉量,分析了影响下沉量的主要因素,比较了实测下沉量与常用经验公式计算值... 详细信息

为了研究内河限制性航道中船舶航行下沉量,建立了室内概化物理模型,开展试验研究。模拟测试了1000~3000 t级船舶在不同渠道宽度、水深及航速条件下船舶航行的下沉量,分析了影响下沉量的主要因素,比较了实测下沉量与常用经验公式计算值的误差及相关系数,提出了以船舶方形系数、航速、阻塞比为变量的下沉量计算改进公式,并进行了验证。研究结果表明,所提改进公式可用于内河限制性航道的水深计算及航道断面设计。

关键词：船舶内河下沉量航道

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A REVOCATION SCHEME FOR THE CLOUD COMPUTING ENVIRONMENT

A REVOCATION SCHEME FOR THE CLOUD COMPUTING ENVIRONMENT

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2011 IEEE International Conference on Cloud Computing and Intelligence Systems(CCIS2011)

作者： xiaobiao li,Qiaoyan Wen State Key Laboratory of Networking and Switching Technology,Beijing University of Posts and Telecommunications,Beijing,China

In order to meet the authentication requirement of the revoking frequently and dynamic network environment,a revocation scheme for the cloud computing environment is *** entering,leaving,revoking and authentication of entities are implemented based on the public key cryptography and the secure dynamic one-way accumulator,and the cross-domain property is also *** results show that the proposed scheme is provable secure to realize the identity authentication,session key agreement and key update with entity secrecy and perfect forward secrecy *** the cloud computing environment,compared with the existing schemes,this solution has a higher level of security,better performance and more comprehensive problem solving for revocation.

关键词： cloud computing revocation authentication cross-domain

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基于多传感器时频分布的机械故障信号欠定盲源分离方法

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武汉科技大学学报 2018年第6期41卷 453-458页

作者：李小彪吕勇易灿灿武汉科技大学冶金装备及其控制教育部重点实验室湖北武汉430081 武汉科技大学机械传动与制造工程湖北省重点实验室湖北武汉430081

结合多传感器时频分布(multisensor time-frequency distributions,MTFD)和盲源分离(blind source separation,BSS)的特点,提出一种针对机械复合故障信号的欠定盲源分离方法。首先利用Wigner-Ville分布将观测信号转化为MTFD矩阵;然后对该矩阵进行白化处理和噪声阈值处理,并对其自动项进行选择,对其特征向量进行集群处理,从而得到源信号TFD的估计;最后对源信号进行重建,得到源信号的估计。仿真及试验结果表明,本文所提出的方法在处理非平稳复合信号的欠定盲源分离方面具有很好的效果。

关键词：多传感器时频分布欠定盲源分离故障诊断 Wigner-Ville分布故障信号

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