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Geology and mineralization of the supergiant Shimensi granitic-type W-Cu-Mo deposit(1.168 Mt)in northern Jiangxi,South China:A Review

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China Geology 2022年第3期5卷 510-527页

作者： Zhi-hui Zhang Da Zhang Xin-kui Xiang Xin-you Zhu Xiao-long He Development and research center of China Geological Survey Ministry of Natural ResourcesBeijing 100037China China University of Geosciences Beijing 100083China Geological team 916 of Jiangxi Geology&Mineral Exploration Bureau Jiujiang 332100China beijing institute of Geology and Mineral Resources Beijing 100012China College of Environment and Resources Xiangtan UniversityXiangtan 411105China

The Shimensi deposit is a recently discovered W-Cu-Mo polymetallic deposit located in the Jiangnan porphyry-skarn W belt in South China.The deposit has a resource of 0.74×10^(6)t of WO_(3)accompanied by 0.4×10^(6)t Cu and 28000 t Mo and other useful components like Ga,making it one of the largest W deposits in the world.This paper is aimed to reveal the ore-controlling mechanisms of the Shimensi deposit,involving the role of the ore-related granites,the tectonic background for its formation,and the metallogenesis model.The systematic geological survey suggests multi-types of alteration are developed in the deposit,mainly including greisenization,potassic-alteration,sericitization,chloritization,and silicification.Drilling engineering data and mining works indicate that the Shimensi deposit consists of two main orebodies of I and II.Therein,the W resource has reached a supergiant scale,and the accompanied Cu,Mo,Au,Bi,Ga,and some other useful components are also of economic significance.The main ore-minerals consist of scheelite,wolframite and chalcopyrite.Disseminated mineralization is the dominant type of the W-Cu-Mo polymetallic orebodies,and mainly distributes in the inner and external contact zone that between the Neoproterozoic biotite granodiorite and the Yanshanian granites.The main orebody occurs at the external contact zone,and the pegmatoid crust near the inner contact zone is an important prospecting marker of the W mineralization.Of them,the disseminated W ores within the wall rock of the Neoproterozoic biotite granodiorite is a new mineralization type identified in this paper.Combining previous geochronological and isotopic data,we propose that the mineralization of the Shimensi deposit is closely related to the intruding of the Yanshanian porphyritic biotite granite and granite porphyry.Geochemical data suggest that the biotite granodiorite is rich in Ca and had provided a large amount of Ca for the precipitation of scheelite in this area.Thus,it is a favorable wall rock type for W mineralization.The

关键词： Tungsten deposit Granitic-type deposit Metallogenesis Lower Yangtze metallogenic belt Porphyry-skarn W belt Mineral exploration engineering Shimensi Dahutang ore field South China

Strategies of Removing Residual Lithium Compounds on the Surface of Ni-Rich Cathode Materials

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Chinese Journal of Chemistry 2021年第1期39卷 189-198页

作者： Yuefeng Su Linwei Li Gang Chen Lai Chen Ning Li Yun Lu Liying Bao Shi Chen Feng Wu beijing Key Laboratory of Environmental Science and engineering Schoo of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China beijing Institute of Technology Chongqing Innovation center Chongqing 401120China

Ni-rich cathode materials have become one of the most promising cathode materials for advanced high-energy Li-ion batteries(LIBs)owing to their high specific capacity.However,Ni-rich cathode materials are sensitive to the trace H2O and CO2 in the air,and tend to react with them to generate LiOH and Li2COg at the particle surface region(named residual lithium compounds,labeled as RLCs).The RLCs will deteriorate the comprehensive performances of Ni-rich cathode materials and make trouble in the subsequent manufacturing process of electrode,including causing low initial coulombic efficiency and poor storage property,bringing about potential safety hazards,and gelatinizing the electrode slurry.Therefore,it is of considerable significance to remove the RLCs.researchers have done a lot of work on the corresponding field,such as exploring the formation mechanism and elimination methods.This paper investigates the origin of the surface residual lithium compounds on Ni-rich cathode materials,analyzes their adverse effects on the per-formance and the subsequent electrode production process,and summarizes various kinds of feasible methods for removing the RLCS.Finally,we propose a new research direction of eliminating the lithium residuals after comparing and summing up the above.We hope this work can provide a reference for alleviating the adverse effects of residual lithium compounds for Ni-rich cathode materials'industrial production.

关键词： Materials science Rechargeable battery Lithium Ni-rich cathode material Residual lithium compounds

Improving utilization of nests and decreasing mislaid eggs with narrow width of group nests

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International Journal of Agricultural and Biological engineering 2018年第1期11卷 83-87页

作者： Hongya Zheng Baoming Li Gang Chen Chaoyuan Wang College of Water Resources and Civil engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Agricultural engineering in Structure and Environment Ministry of AgricultureBeijing 100083China beijing engineering research center for Livestock and Poultry Healthy Environment Beijing 100083China

Provision of nest boxes is necessary for laying hens,especially in non-cage systems.This study investigated the effects of nest width on nest utilization and mislaid eggs.Hy-Line Browns hens were transferred from conventional cages to perchery pens at 12 weeks of age.Two experiments were conducted to mutually verify the hypothesis that narrowing group nests would improve nest utilization and reduce mislaid eggs.In experiment 1,group nests of 150 cm wide in two pens were partitioned at intervals of 50 cm and 37 cm,respectively.In experiment 2,partition panels were removed after acclimation.The number of mislaid eggs and nest eggs in each pre-set section were compared.Results indicated that narrowing group nests had positive effects on improving usage uniformity and efficiency of group nests.Nest eggs were more evenly distributed on the egg belt in both narrowed group nests,which was indicated by the significant decrease of variance among different sections(p<0.001).The proportion of mislaid eggs decreased by 3.5%in 37 cm treatment(p<0.05)and 4.7% in 50 cm treatment(p<0.001),respectively.As expected,reuse of the 150 cm group nests after removal of partition panels lowered the usage uniformity of group nests.A growth of three percentage points was found for the proportion of mislaid eggs after removing the partition panels in 50 cm treatment.The present results indicated that it is the width of the nest box that works for a better use of group nests.In conclusion,adding partition panels at intervals of 50 cm and 37 cm in group nests both are effective on nest usage and decreasing the occurrence of mislaid eggs.

关键词： group nest nest width utilization mislaid eggs hen house non-cage system bird welfare

Controlled Growth of Multidimensional Interface for High-Selectivity Ammonia Production

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CCS Chemistry 2023年第7期5卷 1653-1662页

作者： Xuchen Zheng Yurui Xue Chao Zhang Yuliang Li CAS Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190 School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100190 Science center for Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringInstitute of Frontier and Interdisciplinary ScienceJinan 250100

The efficient production of ammonia by reducing nitrates at room temperature and ambient pressure is a promising alternative to the Haber-Bosch process and can effectively overcome the attendant water pollution issues.Herein,a new idea has been realized for rational and selective construction of the sp-carbon-metal-carbon interface,comprised of electronic-donating triple bonds in graphdiyne and electron-withdrawing iron carbides,for a highly efficient nitrate reduction reaction.The as-prepared sp-carbon-metal-carbon interfacial structures greatly increase the charge transfer ability and electrical conductivity of the system.The proposed concept of incomplete charge transfer has demonstrated significantly high selectivity,activity,and stability in catalytic system.The catalyst exhibits high Faradaic efficiency of over>95%and a NH3 yield rate up to 205.5μmolNH_(3) cm^(-2) h^(-1) in dilute nitrate conditions without any contaminant.

关键词： graphdiyne donor-acceptor interface incomplete charge transfer high selectivity ammonia production

Discovery of Cosmic Spherules from the Mesoproterozoic Strata and its Significance——in Case of the Ming Tombs Area, beijing

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 38-56页

作者： SONG Tianrui ZHENG Ning LIU Yongqing KUANG Hongwei PENG Nan LI Chao TANG Jigang YAN Qinggao GAO Linzhi ZHU Zhicai XIA Xiaoxu WANG Yuchong Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China National research center of Geoanalysis Beijing 100037China Faculty of Land Resource engineering Kunming University of Science and TechnologyKunming 650093YunnanChina beijing General research Institute of Mining and Metallurgy Beijing 100044China

This study covers cosmic spherules derived from the Mesoproterozoic Dahongyu Formation in the Ming Tombs area, beijing. The cosmic spherules include iron oxide cosmic spherules, carbonaceous chondrites, and atomic iron "steely bead"-shaped cosmic spherules. The mineral assemblage of silicon carbide, forsterite, zircon, and glass spherules and fragments were picked from melt-silicified carbonate of the Mesoproterozoic Dahongyu Formation(ca. 1625 Ma). Cosmic spherule assemblages are solely discovered from sedimentary rocks in China. Platinum group elements(PGE) were determined for the first time in cosmic spherules and associated minerals. PGE comparative observation between meteorite and cosmic spherules is presented in this study. It is recognized that an extraterrestrial meteorite impact event might have occurred in the Dahongyu Stage. The main evidence is a large number of iron cosmic spherules in silicified oncolitic limestone, and associated cosmic silicon carbide, glass spherules, and fragments, as well as the presence of forsterite. The impact-volcanic crater is characteristic of a big black shale block dropped into the bended silicified limestone.

关键词： cosmic spherules carbonaceous chondrite meteorite PGE Proterozoic strata beijing impact event

The problem of fluid-dynamics in semicircular canal

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Science China Mathematics 2000年第5期43卷 517-526页

作者：徐明瑜谭文长 Institute of Mathematics and Systematical Science Research Center for Biomedical Engineering Shandong University Jinan 250100 China Department of Mechanics and engineering Science Peking University Beijing 100871 China

An analytical solution with high accuracy which holds for any values of E for fluid-dynamics model eguation in a single semicircular canal presented by Buskirk and his co-workers has been ob-tained. it not only includes ali of the results of Buskirk et al. but also covers three possible kinds of dy-namical response modes in practice. The theoretical results are in betler agreement with those of ex-perimental observations. This investigation has laid a reliable theoretical foundation for quantitatively understanding fluid-dynamics in semicircular canal, especially fluid dynamical response. The distribu-tion of the velocity of the endolymph in semicircular canal is given. A nonstandard method of the in-verse Laplace transform is presented.

关键词： semicircular canal fluid dynamics analytical solution frequency response impulse response non-standard inverse Laplace transform.

Unexpected sedimentation patterns upstream and downstream of the Three Gorges Reservoir:Future risks

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International Journal of Sediment research 2019年第2期34卷 108-117页

作者： Yifan Huang Jinsheng Wang Mei Yang College of Water Sciences Beijing Normal University engineering research center of Groundwater Pollution Control and Remediation Ministry of Education National Geomatics center of China

This paper summarizes the latest developments,future prospects,and proposed countermeasures of reservoir sedimentation and channel scour downstream of the Three Gorges Reservoir(TGR)on the Yangtze River in China.Three key results have been found.(1)The incoming sediment load to the TGR has been significantly lower than expected.(2)The accumulated volume of sediment deposition in the TGR is smaller than expected because the overall sediment delivery ratio is relatively low,and the deposition in the near-dam area of the TGR is still developing.(3)River bed scour in the river reaches downstream of the Gezhouba Dam is still occurring and channel scour has extended to reaches as far downstream as the Hukou reach.Significantly,sedimentation of the TGR is less problematic than expected since the start of operation of the TGR on the one hand;on the other hand,the possible increases in sediment risks from dependence on upstream sediment control,deposition in the reservoir,and scour along middle Yangtze River should be paid more attention.(1)Sediment trapped by dams built along the upper Yangtze River and billion tons of loose materials on unstable slopes produced by the Wenchuan Earthquake could be new sediment sources for the upper Yangtze River.More seriously,possible release of this sediment into the upper Yangtze River due to new earthquakes or extreme climate events could overwhelm the river system,and produce catastrophic consequences.(2)Increasing sediment deposition in the TGR is harmful to the safety and efficiency of project operation and navigation.(3)The drastic scour along the middle Yangtze River has intensified the down-cutting of the riverbed and erosion of revetment,it has already led to increasing risk to flood control structures and ecological safety.It is suggested to continue the Field Observation Program,to initiate research programs and to focus on risks of sedimentation.

关键词： Yangtze River Three Gorges Reservoir Sedimentation Risk

Applications of structural efficiency assessment method on structural-mechanical characteristics integrated design in aero-engines

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Chinese Journal of Aeronautics 2020年第4期33卷 1260-1271页

作者： Jie HONG Tianrang LI Huaqiang ZHENG Yanhong MA School of Energy and Power engineering Beihang UniversityBeijing 100083China Collaborative Innovation center of Advanced Aero-Engine Beijing 100083China AECC Hunan Aviation Powerplant research Institute Zhuzhou 412002China

In the design process of advanced aero-engines,it is necessary to carry out an effective analysis method between structural features and mechanical characteristics for a better structural optimization.Based on the structural composition and functions of aero-engines,the concept and contents of structural efficiency can reflect the relation between structural features and mechanical characteristics.In order to achieve the integrated design of structural and mechanical characteristics,one quantitative analysis method called Structural Efficiency Assessment Method(SEAM)was put forward.The structural efficiency coefficient was obtained by synthesizing the parameters to quantitatively evaluate the aero-engine structure design level.Parameterization method to evaluate structural design quality was realized.After analyzing the structural features of an actual dual-rotor system in typical high bypass ratio turbofan engines,the mechanical characteristics and structural efficiency coefficient were calculated.Structural efficiency coefficient of high-pressure rotor(0.43)is higher than that of low-pressure rotor(0.29),which directly shows the performance of the former is better,there is room for improvement in structural design of the low-pressure rotor.Thus the direction of structural optimization was pointed out.The applications of SEAM shows that the method is operational and effective in the evaluation and improvement of structural design.

关键词： Aero-engines Integrated design Mechanical characteristics Structural efficiency Structural optimization

A new synthetic route to MgO–MgAl2O4–ZrO2 highly dispersed composite material through formation of Mg5Al2.4Zr1.7O12 metastable phase: synthesis and physical properties

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 332-341页

作者： Peng Jiang Guo-xiang Yin Ming-wei Yan Jia-lin Sun Bin Li Yong Li School of Materials Science and engineering University of Science and Technology Beijing Beijing 100083 China Collaborative Innovation center of Steel Technology University of Science and Technology Beijing Beijing 100083 China

Mg_5Al_(2.4)Zr_(1.7)O_(12) metastable phase was successfully synthesized from analytical-grade Mg O,α-Al_2O_3,MgAl_2O_4,and ZrO_2 under an N_2 atmosphere.The sintering temperature was varied from 1650 to 1780°C,and the highest amount of Mg_5Al_(2.4)Zr_(1.7)O_(12) appeared in the composite material when the sintering temperature was 1760°C.According to our research of the formation mechanism of Mg_5Al_(2.4)Zr_(1.7)O_(12),the formation and growth of MgAl_2O_4 dominated when the temperature was not higher than 1650°C.When the temperature was higher than 1650°C,MgO and ZrO_2 tended to diffuse into MgAl_2O_4 and the Mg_5Al_(2.4)Zr_(1.7)O_(12) solid solution was formed.When the temperature reached 1760°C,the formation of Mg_5Al_(2.4)Zr_(1.7)O_(12) was completed.The effect of Mg Al_2O_4 spinel crystals was also studied,and their introduction into the composite material promoted the formation and growth of Mg_5Al_(2.4)Zr_(1.7)O_(12).A highly dispersed MgO–Mg Al_2O_4–ZrO_2 composite material was prepared through the decomposition of the Mg_5Al_(2.4)Zr_(1.7)O_(12) metastable phase.The as-prepared composite material showed improved overall physical properties because of the good dispersion of MgO,MgAl_2O_4,and ZrO_2 phases.

关键词： metastable phases formation mechanisms composite materials refractory materials synthesis physical properties