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The Characteristics of Ore-Controlling Structure in Baoshan Cu-Pb-Zn Polymetallic Deposit,Hunan Province 被引量:3
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作者 QI Fan-yu1,ZHANG Zhi1,2,LI Yong-sheng1,ZHEN Shi-min1,JIA De-long1,GONG Fan-ying1,GONG Xiao-dong1,HE Peng1(1.School of Earth & Resources,China University of Geosciences Beijing,Beijing 100083,China 2.Development and Research Center,Beijing 100037 China) 《矿物学报》 CAS CSCD 北大核心 2011年第S1期823-824,共2页
The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part ... The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part of Nanling polymetallic deposit belt.The outcropping stratas consist of upper Devonian Shetianqiao,Xikuangshan Formation,Lower Carboniferous Menggong’ao,Shidengzi,Ceshui,and Zimenqiao Formation.Igneous rocks in the Baoshan ore area mainly comprise granodiorite porphyry.Furthermore,the radio isotopic age ranges from 123 Ma to 183 Ma,belonging to the early to middle Yanshanian. 展开更多
关键词 PB The Characteristics of ore-controlling structure in Baoshan Cu-Pb-Zn Polymetallic Deposit Hunan Province ZN CU
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Analysis of Ore-controlling Structure in the Qifengcha-Detiangou Gold Deposit,Huairou County,Beijing 被引量:1
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作者 CHEN Bailin LI Zhongjian DONG Faxian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第1期94-100,共7页
The Qifengcha-Detiangou gold deposit is a medium-sized deposit recently found in Huairou County, Beijing. It belongs to the altered mylonite type with superimposed quartz vein type and is related to the early Yanshani... The Qifengcha-Detiangou gold deposit is a medium-sized deposit recently found in Huairou County, Beijing. It belongs to the altered mylonite type with superimposed quartz vein type and is related to the early Yanshanian magmatic activity. Characterized by multiperiodic activity, the NE-trending Qifengcha fault is a regional ore-controlling structure in the area, and gold mineralization develops only in its southeastern part. Meanwhile, gold mineralization is controlled by the Yunmengshan metamorphic core complex. The nearly N-S- and E-W-trending low-angle detachment faults, reformed by the Qifengcha fault in the northwestern part of the core complex, are the main ore-bearing faults. All discovered gold deposits are located within an area 1.5–4.0 km away from the boundary of the upwelling centre. The N-S- (NNE-) and E-W-trending ore-bearing faults are ductile-brittle structural zones developing in shallow positions and subjected mainly to compressive deformation. The structural ore-controlling effects are as follows. (1) The attitude, shape, and distribution of gold orebodies are controlled by faults. (2) There is a negative correlation between the gold abundance and the magnetic anisotropy (P) of the altered mylonite samples from the deposit, which shows that the gold mineralization is later than the structural deformation. (3) Quartz vein type mineralization is superimposed on altered mylonite type mineralization. (4) In mineralized mylonite, the stronger the ductile shear deformation, the easier the late-stage gold mineralization to occur and the higher the gold abundance. The richest gold mineralization occurs only around the centre of the fault subjected to the strongest deformation. 展开更多
关键词 analysis of ore-controlling structure Qifengcha-Detiangou gold deposit BEIJING
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Structural transformation of metal–organic framework with constructed tetravalent nickel sites for efficient water oxidation 被引量:1
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作者 Weijian Wu Zhen Gao +6 位作者 Qun Li Zhiya Wang Shiyin Liu Hongbo Wu Yuanchun Zhao Yalong Jiao Xiaojia Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第11期404-411,I0011,共9页
A mixture of Ni and Fe oxides is among the most commonly active catalysts for the oxygen evolution reaction(OER)during the water oxidation process.In particular,Ni oxide incorporated with even a small amount of Fe lea... A mixture of Ni and Fe oxides is among the most commonly active catalysts for the oxygen evolution reaction(OER)during the water oxidation process.In particular,Ni oxide incorporated with even a small amount of Fe leads to substantively enhanced OER activity.However,the critical role of Fe species during the electrocatalytic process is still under evaluation.Herein,we report nickel(oxy)hydroxide incorporated with Fe through the surface reconstruction of a bimetallic metal-organic framework(NiFe-MOF)during the water oxidation process.The spectroscopic investigations with theoretical calculations reveal the critical role of Fe in promoting the formation of highly oxidized Ni^(4+),which directly correlates with an enhanced OER activity.Both the geometric and electronic structu res of the as-reconstructed Ni_(1-x)Fe_(x)OOH electrocatalysts can be delicately tuned by the Ni-Fe ratio of the bimetallic NiFe-MOF,further affecting the catalytic activity.As a result,the Ni_(1-x)Fe_(x)OOH derived from Ni_(0.9)Fe_(0.1)-MOF delivers low overpotentials of 260 mV at 10 mA cm^(-2)and 400 mV at 300 mA cm^(-2). 展开更多
关键词 structural transformation Bimetallic metal-organic framework Oxygen evolution reaction In-situ Raman spectroscopy High-valence metal sites
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Analysis of Ore-Controlling Structures of the Xincheng-Hexi Gold Deposit,Shandong Province,China
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作者 LEI Shibin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期548-553,共6页
Based on quantitative and semi-quantitative mathematical and mechanical analysis of the shape, motion, structural factors, stress field and deformation field of the ore-hosting faults in the Xincheng-Hexi gold deposit... Based on quantitative and semi-quantitative mathematical and mechanical analysis of the shape, motion, structural factors, stress field and deformation field of the ore-hosting faults in the Xincheng-Hexi gold deposit, the ore-controlling features of faults and mineralization mechanism are discussed. It is concluded that the mineralization is controlled by the main faults, subsidiary fractures, joint density, mechanical features and deformation of the faults. The ore bodies are mainly located in the lower part of the convex crest and upper part of the concave trough of the main undulating fault surface. Mineralization is positively correlated to the development of subsidiary fractures and joints, which correspond to zones of low internal stress and high body strain and shear strain. They are favourable positions for mineralization and alteration. 展开更多
关键词 SHANDONG gold deposit ore-controlling structure
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Structural reconstruction of Sn-based metal-organic frameworks for efficient electrochemical CO_(2) reduction to formate
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作者 Yachen Deng Shifu Wang +1 位作者 Yanqiang Huang Xuning Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第3期353-359,共7页
MOF-based materials have been widely explored in electrochemical CO_(2)reduction reactions for the production of valuable chemicals.Understanding the reconstruction of those catalysts under working conditions is cruci... MOF-based materials have been widely explored in electrochemical CO_(2)reduction reactions for the production of valuable chemicals.Understanding the reconstruction of those catalysts under working conditions is crucial for the identification of active sites and clarification of reaction mechanism.Herein,a series of six N coordinated Sn-based metal-organic frameworks(Sn-N6-MOFs)are newly developed for electrochemical CO_(2)reduction(CO_(2)RR).2%Sn-N6-MOF achieves the optimal catalytic performance with a formate Faradaic efficiency of~85%and a current density of 23 mA·cm^(-2) at-1.23 V vs.RHE.In-situ Raman results combined with ex-situ ^(119)Sn Mössbauer measurements reveal the structural reconstruction of Sn-N6-MOFs during CO_(2)RR,generating tin nanoclusters as the real active sites for CO_(2)electroreduction to HCOOH. 展开更多
关键词 structural reconstruction Metal-organic frameworks Mössbauer spectroscopy Electrochemical CO_(2)reduction
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Ore-controlling Regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District
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作者 Gong Hongsheng Han Runsheng +2 位作者 Li Ziteng Ren Tao Wang Jiasheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期202-203,共2页
1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is ... 1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is strictly controlled by fault structures.It has developed to one of the famous production bases of lead&zinc and germanium in China. 展开更多
关键词 PB ore-controlling Regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District Zn
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GEOCHEMICAL REASERCH ON ORE-CONTROLLING STRUCTURE IN LIAODONG LUOQUANBEI-BAIYUN GOLD MINERAL BELT
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作者 LI Pei zheng, TIAN Shu hai, WANG Qian cheng (College of Resource, Environment and Civil Engeneering, Central South University, Changsha 410083, China) 《Geotectonica et Metallogenia》 2001年第1期159-161,共3页
In recent2 0 years,because of the finding ofmany large- superlargegold deposits,we re- new the theories for prospecting and gain many things and conceptions.The current geo- chemical and gold- forming theories underli... In recent2 0 years,because of the finding ofmany large- superlargegold deposits,we re- new the theories for prospecting and gain many things and conceptions.The current geo- chemical and gold- forming theories underline the importance of the early submarine volcano- sedimentation,metamorphic differention,sedimentation of terrigenous clastics,thermal spring and it’s sedimentation,syngenesis process and other hypergene supplying the source for metallogenic materials.According to the study for source bed(rock) and depsitional for- mation of gold,we find that gold will be gradually enriched and mineralized in source bed (rock) ,because of variousgeologicprocesses,such as regional metamorphism ormigmatiza- tion,geothermal bittern,volcanism. The ore- control of deep and giant fault and ductile shear beltand tectono- flash space is emphasized,especially,we should notice the long- term, succession and multistage of the 展开更多
关键词 rock SE GEOCHEMICAL REASERCH ON ore-controlling structurE IN LIAODONG LUOQUANBEI-BAIYUN GOLD MINERAL BELT ORE
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A Zinc(Ⅱ) Coordination Framework Based on Terpyridine and 5-Nitroisophthalic Acid Mixed Ligands: Synthesis, Crystal Structure and Fluorescence Property 被引量:7
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作者 陈勇强 田源 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第11期1587-1592,共6页
A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determin... A new coordination framework, {[Zn(L1)(5-nipc)]·H2O}n(1, L1 = 4ˊ-(4-pyridyl)-4,2ˊ:6ˊ,4ˊˊ-terpyridine, 5-nipc = 5-nitroisophthalic acid), has been prepared under hydrothermal conditions, and determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR and powder X-ray diffraction. Complex 1 crystallizes in monoclinic, space group C2/c with a = 29.983(9), b = 13.709(3), c = 14.391(3)A, β = 114.93(4)°, V = 5364(2) A3, Dc = 1.493 g/cm^3, C28H19N5O7 Zn, Mr = 602.85, F(000) = 2464, μ(Mo Kα) = 0.972 mm^-1, Z = 8, R = 0.0935 and w R = 0.1509 for 4724 observed reflections(I 〉 2σ(I)). The structure of 1 exhibits a three-dimensional(3D) network with a layer-pillar structure. The fluorescence property of 1 is also investigated. 展开更多
关键词 coordination framework mixed-ligand approach crystal structure property
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Hydrothermal Synthesis,Structure and Properties of a 3D Pillar-layered Metal-organic Framework Based on Amino-arenedisulfonate Ligand 被引量:6
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作者 关磊 罗贯华 王莹 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第11期1795-1804,共10页
One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antip... One novel metal-organic framework(MOF), [Ba(L)(HO)](1, HL =aniline-2,5-disulfonic acid), has been synthesized by hydrothermal method. Each barium atom is eleven-coordinated into a distorted monocapped pentagonal antiprismatic arrangement. Compound 1 shows an interesting 3 D pillar-layered structure constructed from 2 D inorganic layers[Ba(SO)(HO)]and organic pillars of phenyl moieties of L2-linkages. The inorganic layers are supported by the organic pillars, generating a novel 3 D open framework structure with {3, 4~6, 5~5, 6~5,7~4}2{3}{5} topology. The result of fluorescence measurement can reveal that the decayed emission band centered at 492 nm may be caused by the interactions of the ligands and the metal ions.Compound 1 exhibits selective toward the adsorption of COover Nat 273 K. 展开更多
关键词 hydrothermal synthesis metal-organic framework pillar-layered structure coordination polymer
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Multi-objective Optimization Design of Wing Structure with the Model Management Framework 被引量:3
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作者 安伟刚 李为吉 苟仲秋 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第1期31-35,共5页
Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance un... Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance unmanned aviation vehicle(UAV). In order to improve efficiency it is proposed to construct a model management framework to perform the multi-objective optimization design of wing structure. The sufficient accurate approximation models of objective and constraint functions in the wing structure optimization model are built when using the model management framework, therefore in the evolutionary algorithm a number of finite element analyses can he avoided and the satisfactory multi-objective optimization results of the wing structure of the high altitude long endurance UAV are obtained. 展开更多
关键词 wing structure UAV multi-objective opti-mization model management framework SM- MOPSO
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Synthesis and Crystal Structure of a Zeolite-like Metal-organic Framework Based on the Triazole Ligand 被引量:4
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作者 李东平 梁小强 +2 位作者 许岩 李承辉 游效曾 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第11期1708-1714,共7页
A novel zeolite-like metal-organic framework, [Cd12(trz)12'F10'(SiF6)3]·(H3O)4 (Htrz = 1,2,4-triazole), has been synthesized under solvothermal conditions using 1H-l,2,4-triazole-3- carboxylic acid and ... A novel zeolite-like metal-organic framework, [Cd12(trz)12'F10'(SiF6)3]·(H3O)4 (Htrz = 1,2,4-triazole), has been synthesized under solvothermal conditions using 1H-l,2,4-triazole-3- carboxylic acid and CdF2 as the starting materials. The complex has been characterized by elemental analysis, IR, SEM-EDS, gas adsorption, powder and single-crystal X-ray diffraction analyses. The title complex crystallizes in the cubic 1-43m space group, with a = 14.6436(8), V= 3140.1(3)A3, Z = 2, Mr = 2857.96, D,.= 3.023 g/cm3 and F(000) = 2668. The final R = 0.0653 and wR = 0.1880 for 586 observed reflections with 1 〉 2σ(I). In the title complex, three adjacent Cd(ll) centers are connected by three p3-bridging triazole ligands to form triagonal secondary building units (SBUs), which are further interconnected to form a three-dimensional skeleton with tetrahedral cages. 展开更多
关键词 TRIAZOLE crystal structure zeolite-like framework Cd(ll) complex
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Land Use Structure Optimization Under Systematic Framework 被引量:2
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作者 LIU Yanfang HUANG Liangprofessor,School of Resource and Environment Science,Wuhan University,129 Luoyu Road,Wuhan 430079,China. 《Geo-Spatial Information Science》 2002年第3期46-52,共7页
This paper puts forward the concept of land use structure optimization under space_time coupling through analyzing the systematic characteristic of land use structure optimization.It mainly expounds the construction o... This paper puts forward the concept of land use structure optimization under space_time coupling through analyzing the systematic characteristic of land use structure optimization.It mainly expounds the construction of land use structure optimization model at different levels.Lastly,this paper explains the practicableness of land use structure optimization under systematic framework through the example of Qionghai city. 展开更多
关键词 LAND USE structurE OPTIMIZATION systematic framework model CONSTRAINTS
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Precambrian Geochronology, Chronotectonic Framework and Model of Chronocrustal Structure of the Zhongtiao Mountains 被引量:10
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作者 Sun Dazhong Li Huimin +3 位作者 Lin Yuanxian Zhou Huifang Zhao Fengqing Tang Min Tianjin Institute of Geology and Mineral Resources, Chinese Academy of Geological Sciences, Tianjin Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1992年第1期23-37,共15页
The Zhongtiao Mountains, a typical exposure area of Precambrian rocks, are a concentration area of vari-ous types of copper deposit. The rocks were dated using several dating methods. Based on the age data ob-tained b... The Zhongtiao Mountains, a typical exposure area of Precambrian rocks, are a concentration area of vari-ous types of copper deposit. The rocks were dated using several dating methods. Based on the age data ob-tained by means of three methods, several aspects are dealt with: (1) the dating results obtained by differentmethods and their geological implications have been compared; (2) a chronotectonic framework has been con-structed by means of these reliable ages, which indicates that the ages of the rocks of the Proterozoic mobilebelt fall in a time span of 2400 to 2000 Ma during which global magmatic records are lacking and reflects theages of important events in the mobile belt; (3) according to the ages of inherited zircons, neodymium modelage of the depleted mantle sources (T_(DM)) and geochemical and geological data, a model of Precambrianchronocrustal structure has been constructed, representing a typical for the North China craton. 展开更多
关键词 Precambrian Geochronology Chronotectonic framework and Model of Chronocrustal structure of the Zhongtiao Mountains
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Construction of all-organic low dielectric polyimide hybrids via synergistic effect between covalent organic framework and cross-linking structure 被引量:3
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作者 Wanjing Zhao Zhaoyang Wei +6 位作者 Chonghao Lu Yizhang Tong Jingshu Huang Xianwu Cao Dean Shi Robert KYLi Wei Wu 《Nano Materials Science》 EI CAS CSCD 2023年第4期429-438,共10页
Polyimide(PI)is a promising electronic packaging material,but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the monomer.Herein,a series of... Polyimide(PI)is a promising electronic packaging material,but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the monomer.Herein,a series of allorganic PI hybrid films were successfully prepared by introducing the covalent organic framework(COF),which could induce the formation of the cross-linking structure in the PI matrix.Due to the synergistic effects of the COF fillers and the cross-linking structure,the PI/COF hybrid film containing 2 wt%COF exhibited the lowest dielectric constant of 2.72 and the lowest dielectric loss(tanδ)of 0.0077 at 1 MHz.It is attributed to the intrinsic low dielectric constant of COF and a large number of mesopores within the PI.Besides,the cross-linking network of PI prevents the molecular chains from stacking and improves the fraction of free volume(FFV).The molecular dynamics simulation results are well consistent with the dielectric properties data.Furthermore,the PI/COF hybrid film with 5 wt%COF showed a significant enhancement in breakdown strength,which increased to 412.8 kV/mm as compared with pure PI.In addition,the PI/COF hybrid film achieve to reduce the dielectric constant and thermal expansion coefficient(CTE).It also exhibited excellent thermal,hydrophobicity,and mechanical performance.The all-organic PI/COF hybrid films have great commercial potential as next-generation electronic packaging materials. 展开更多
关键词 POLYIMIDE Covalent organic framework All-organic Cross-linking structure Dielectric property Hybrid film
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[(n-C_4H_9)_3SnO_2C(CH_2)_2CO_2Sn(C_4H_9-n)_3]: A Novel Three-dimensional Framework Structure of Organotin Complex 被引量:2
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作者 尹汉东 王传华 +2 位作者 马春林 王勇 房海霞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第4期387-390,共4页
The bis(tributyltin) ester of succinic acid was synthesized by the reaction of disodium salt of succinic acid with tributyltin chloride in a molar ratio of 1:2. The crystal structure was determined by X-ray single-cry... The bis(tributyltin) ester of succinic acid was synthesized by the reaction of disodium salt of succinic acid with tributyltin chloride in a molar ratio of 1:2. The crystal structure was determined by X-ray single-crystal diffraction. It belongs to orthorhombic with space group Pccn, a = 20.949(3), b = 17.470(3), c = 20.345(3) Angstrom, V = 7446(2) Angstrom(3), Z = 8, D-c = 1.242 g/cm(3), mu = 1.365 mm(-1), F(000) = 2864, R = 0.0544 and wR = 0.1417. The tin atom is of five-coordination in a trigonal bipyramidal structure by bridging two carboxylate groups in different directions and the resulting structure which contains straight twist large ring channels along the axes of a, b and c is a three-dimensional framework polymer containing two different tin atoms. 展开更多
关键词 TRIBUTYLTIN glutaric acid crystal structure three-dimensional framework structure
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Tuning the electronic structure of a metal-organic framework for an efficient oxygen evolution reaction by introducing minor atomically dispersed ruthenium 被引量:3
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作者 Yuwen Li Yuhang Wu +5 位作者 Tongtong Li Mengting Lu Yi Chen Yuanjing Cui Junkuo Gao Guodong Qian 《Carbon Energy》 SCIE CSCD 2023年第2期61-71,共11页
The establishment of efficient oxygen evolution electrocatalysts is of great value but also challenging.Herein,a durable metal–organic framework(MOF)with minor atomically dispersed ruthenium and an optimized electron... The establishment of efficient oxygen evolution electrocatalysts is of great value but also challenging.Herein,a durable metal–organic framework(MOF)with minor atomically dispersed ruthenium and an optimized electronic structure is constructed as an efficient electrocatalyst.Significantly,the obtained NiRu_(0.08)-MOF with doping Ru only needs an overpotential of 187 mV at 10 mA cm^(-2) with a Tafel slop of 40 mV dec^(-1) in 0.1M KOH for the oxygen evolution reaction,and can work continuously for more than 300 h.Ultrahigh Ru mass activity is achieved,reaching 56.7 Ag^(-1)_(Ru) at an overpotential of 200 mV,which is 36 times higher than that of commercial RuO_(2).X-ray adsorption spectroscopy and density function theory calculations reveal that atomically dispersed ruthenium on metal sites in MOFs is expected to optimize the electronic structure of nickel sites,thus improving the conductivity of the catalyst and optimizing the adsorption energy of intermediates,resulting in significant optimization of electrocatalytic performance.This study could provide a new avenue for the design of efficient and stable MOF electrocatalysts. 展开更多
关键词 ELECTROCATALYSIS electronic structure metal-organic framework oxygen evolution reaction
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A New 3-Fold Interpenetrating 3D Zn(Ⅱ) Metal-organic Framework: Synthesis,Structure and Luminescent Property 被引量:2
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作者 苗少斌 李召好 +1 位作者 许春莺 吉保明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第12期1960-1966,共7页
A new Zn(Ⅱ) coordination polymer,namely {[Zn_(1.5)(1,3,5-btc^(3-))(dtb)(H_2O)](H_2O)_2}_n(1)(1,3,5-H_3btc = 1,3,5-benzenetricarboxylic acid,dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene),has been hydr... A new Zn(Ⅱ) coordination polymer,namely {[Zn_(1.5)(1,3,5-btc^(3-))(dtb)(H_2O)](H_2O)_2}_n(1)(1,3,5-H_3btc = 1,3,5-benzenetricarboxylic acid,dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene),has been hydrothermally synthesized and structurally characterized. X-ray single-crystal diffraction determination reveals that 1 crystallizes in the monoclinic C2/c space group with a = 33.811(12),b = 8.406(2),c = 17.296(4) ?,β = 120.593(2)°,V = 4232(2) ?~3,Z = 4,Mr = 1142.88,Dc = 1.794 Mg/m^3,μ = 1.783 mm^(-1),F(000) = 2320,the final R = 0.0338 and wR = 0.0827 for 3043 observed reflections with I 〉 2σ(I). Compound 1 exhibits 1D Zn(Ⅱ)-carboxylate chains,which are connected into a 3D porous framework with large channels by dtb,and then three identical 3D networks are interpenetrated with each other. In addition,the luminescence property of the complex has also been investigated. 展开更多
关键词 metal-organic framework 1 3-di-(1 2 4-triazole-4-yl)benzene crystal structure luminescence
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Auxiliary Ligand Oriented CdⅡ-flexible Dicarboxylic Acid Coordination Frameworks:Syntheses, Structures and Properties 被引量:1
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作者 CHEN Yong-Qiang ZHAI Jia-Xin +1 位作者 TIAN Yuan LIU Xiu-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第8期1311-1319,共9页
Two different CdⅡ coordination frameworks [Cd(L1)(L2)]∞(1) and [Cd(L1)-(L3)(H2O)]∞(2) based on a flexible dicarboxylic acid ligand were obtained by introducing two different nitrogen heterocyclic auxiliary ligands(... Two different CdⅡ coordination frameworks [Cd(L1)(L2)]∞(1) and [Cd(L1)-(L3)(H2O)]∞(2) based on a flexible dicarboxylic acid ligand were obtained by introducing two different nitrogen heterocyclic auxiliary ligands(L1 = 3,3’-[1,3-benzenebis(carbonylimino)]bi(benzoate), L2 = 1,3-bi(4-pyridyl)propane, L3 = 4,4’-bipyridine). Complex 1 crystallizes in triclinic, space group P■ with a = 8.7415(5), b = 12.2247(7), c =16.2415(10) ?, β = 95.6790(10)°, V = 1525.11(16) ?3, Dc = 1.553 mg·m-3, C35H28CdN4O6, Mr = 713.02, F(000) = 724, μ(MoKα) = 0.770 mm–1, Z = 2, R/wR(I > 2σ(I))a = 0.0302/0.0773. However, complex 2 crystallizes in monoclinic, space group P21/n with a = 11.4986(7), b = 23.0911(14), c = 11.9943(8) ?, β = 115.9500(10)°, V = 2863.6(3) ?3, Dc = 1.598 mg·m-3, C32H24CdN4O7, Mr = 688.96, F(000) = 1392, μ(MoKα) = 0.820 mm–1, Z = 4, R/wR(I > 2σ(I))a = 0.0283/0.0631. The structures of two complexes were characterized. Complexes 1 and 2 have different one-dimensional(1D) chain structures. In addition, we have also made a preliminary study on the properties of the two complexes. 展开更多
关键词 COORDINATION framework AUXILIARY LIGAND structure PROPERTY
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Mineralization and Ore-controlling Implications of Low-angle Faults 被引量:1
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作者 CHEN Bailin LIU Jianmin +1 位作者 ZHANG Da WU Jianshe 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第4期438-446,共9页
Abstract Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own par... Abstract Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own particularities. The low-angle fault plays an important role in controlling over some endogenetic metallic ore deposits. Based on studies of the Xiaoban gold deposit, Xinzhou gold deposit, and Longfengchang polymetallic ore deposit, and comparisons with other mines, the authors conclude the ore-controlling implications of low-angle faults as follows. (1) Because of high temperature and high pressure, as well as strong ductile deformation, the internal energy of the elements rises in the large-scale deep ductile low-angle faults, which causes the elements to activate and differentiate from the source rocks, forming ore-bearing hydrothermal solution, and bring mineralization to happen. (2) When rising from depths and flowing along the low-angle faults, the ore-bearing hydrothermal solution will alter and replace the tectonites in the fault zone. The rocks of the hanging side and the heading side differ in lithology, texture and structure, which results in changes or dissimilarities of the physical-chemical conditions. This destroys the balance of the hydrothermal solution system and causes the dissolved ore-forming elements to precipitate; as a result, a deposit is formed. Therefore, the meso-shallow ductile-brittle low-angle faults play the role of a geochemical interface in the process of mineralization. (3) Low-angle faults are often one of the important host structures. 展开更多
关键词 low-angle fault ore-controlling structure structural metallogenesis geochemical interface of mineralization host structure
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Synthesis and Crystal Structure of a Magnesium Metal-organic Framework 被引量:1
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作者 吴兆锋 冯美玲 +2 位作者 胡冰 黄小荥 赵玉宝 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1585-1590,共6页
A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 ... A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 crystallizes in the trigonal system, space group R-3, with a = 11.3427(3), c = 41.5662(18) A, V = 4631.3(3) A^3, Z = 3 and the final R = 0.0457. Its structure features a pillared-layered three-dimensional network with 8.21 A cavities, in which cationic [NH2(CH3)2]^+ or [N(CH3)4]^+ and lattice water molecules are located. Thermal stability of the title compound has also been investigated. 展开更多
关键词 solvothermal synthesis MAGNESIUM metal organic framework crystal structure
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