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Damage and deterioration mechanism and curing technique of concrete structure in main coal cleaning plants 被引量:10
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作者 LV Heng-lin ZHAO Cheng-ming +2 位作者 SONG Lei MA Ying XU Chun-hua 《Mining Science and Technology》 EI CAS 2009年第6期750-755,共6页
Concrete structures in main coal cleaning plants have been rebuilt and reinforced in the coal mines of the Shanghai Datun Energy Sources Co. Ltd., the first colliery of the Pingdingshan Coal Co. Ltd. and the Sanhejian... Concrete structures in main coal cleaning plants have been rebuilt and reinforced in the coal mines of the Shanghai Datun Energy Sources Co. Ltd., the first colliery of the Pingdingshan Coal Co. Ltd. and the Sanhejian mine of the Xuzhou Mining Group Co. Ltd. In these projects, the operating environment and reliability of concrete structures in the main plants of the three companies were investigated and the safety of the structures inspected. Qualitative and quantitative analyses were made on the special natural, technological and mechanical environments around the structures. On the basis of these analyses, we discuss the long-term, combined actions of the harsh natural (corrosive gases, liquids and solids) and mechanical environments on concrete structures and further investigated the damage and deteriorating mechanisms and curing techniques of concrete structures in the main coal cleaning plants. Our study can provide a theoretical basis for ensuring the reliability of concrete structures in main coal cleaning plants. 展开更多
关键词 main coal cleaning plants concrete structure operating environment reliability detection and inspection damage anddeteriorating mechanisms curing technique
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Two New Main Group Metal Coordination Polymers Based on 2,5-Furandicarboxylic Acid: Syntheses and Crystal Structures 被引量:2
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作者 王浩 刘洋 +2 位作者 陈飞 郭雨萌 章应辉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第4期585-593,共9页
By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid (H2FDA) ligand, [Sr2(FDA)E(H2O)5]n (1) and [Ba4(FDA)4(H2O)10]n (2), were produced and char... By using solvothermal method, two new main group metal coordination polymers based on 2,5-furandicarboxylic acid (H2FDA) ligand, [Sr2(FDA)E(H2O)5]n (1) and [Ba4(FDA)4(H2O)10]n (2), were produced and characterized by single-crystal X-ray diffraction analyses, elemental analyses, IR, and powder X-ray diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a = 13.454(3), b = 13.426(3), c = 20.166(4) A, β = 107.06(3)°, V = 3482.4(13)A^3, Dc = 2.188 g/cm^3, CIEH14Sr2O15, Mr = 573.47, F(000) = 2256,μ(MoKα)= 6.21 mm^-1, Z = 8, R = 0.0522 and wR = 0.1229 for 2493 observed reflections (I〉 2σ(I)), and R = 0.0689 and wR = 0.1324 for all data. Compound 2 crystallizes in triclinic, space group el with α = 6.8382(14), b = 10.932(2), c = 25.571(5) A,α = 94.64(3), β= 95.41(3), γ = 107.83(3)°, V= 1799.4(6) A3, Dc = 2.484 g/cm^3, C24H28Ba4O30, Mr = 1345.82, F(000) = 1272,μ(MoKa) = 4.43 mm^-1, Z = 2, R = 0.0485 and wR = 0.0906 for 5020 observed reflections (I〉 2σ(I)), and R = 0.0706 and wR = 0.0991 for all data. In 1, the trinuclear clusters Sr3 are connected with adjacent four clusters by a carboxylate group to produce a two-dimensional (2D) sheet, which is extended by a FDA-based pillar into a 3D framework. In 2, neighbouring trinuclear clusters Ba3 are linked through two -O-C-O- of FDA^2- ligands to form one-dimensional (1D) chains, which are connected by a FDA-based pillar to construct a 2D framework. The thermal stabilities of 1 and 2 are also investigated. 展开更多
关键词 2 5-furandicarboxylic acid main group crystal structure
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Structure of the Intermetallic Compound Ni_3Al Synthesized under Compression of the Powder Mixture of Pure Elements Part Ⅰ: Phase Composition and Microstructure of Main Phase 被引量:4
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作者 M. V. Fedorischeva, V.E.Ovcharenko, O.B.Perevalova and E. V. Kozlov(Institute of Strength Physics and Materials Science, Russian Academy of Sciences, Siberian Branch, Tomsk, Russia) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第6期531-535,共5页
It was shown by TEM and X-ray analysis that there are four types of grains of the main Ni3Al phase in the structure of the intermetallic obtained by the self-propagation high temperature method (SHS). Every type of gr... It was shown by TEM and X-ray analysis that there are four types of grains of the main Ni3Al phase in the structure of the intermetallic obtained by the self-propagation high temperature method (SHS). Every type of grains has its own domain and dislocation structure. There are mono- and polydomains with and without dislocations. The grains of the main phase of monoand polydomains without dislocations and polydomains with dislocations were formed by diffusion in the solid phase. In these conditions NiAl3 phase is located on the grain boundary of the main phase. The Ni2Al3 phase is located at the triple joints of the main phase. 展开更多
关键词 In Al structure of the Intermetallic Compound Ni3Al Synthesized under Compression of the Powder Mixture of Pure Elements Part Phase Composition and Microstructure of main Phase Ni
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STRUCTURE OF MAIN COMPONENT IN PERFUME "ISO-E-SUPER"
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作者 You Zhu YUAN Shu Jing PENG 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第7期507-510,共4页
Addition of myrcene and 3-methyl-3-penten-2-one followed by cyclization afforded perfume 'Iso-E-Super' with 2(?)-acetyl-2β,3β,8,8-tetramethyl-1,2,3,4,5,6,7,8-octalin as main component on the basis of its spe... Addition of myrcene and 3-methyl-3-penten-2-one followed by cyclization afforded perfume 'Iso-E-Super' with 2(?)-acetyl-2β,3β,8,8-tetramethyl-1,2,3,4,5,6,7,8-octalin as main component on the basis of its spectroscopic data. 展开更多
关键词 EU structure OF main COMPONENT IN PERFUME ISO-E-SUPER
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FORMATION OF MESOPHASE MONO-DOMAINS AND MICRO-STRUCTURES IN THIN FILMS OF A SERIES OF COPOLYETHERS CONTAINING BOTH ODD-NUMBERED METHYLENE UNITS
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作者 Feng-chao Xie Jie-ping Liu +3 位作者 Dong-hang Yan Tian-bai He Ru-qing Zheng Er-qiang Chen State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China Department of Polymer Science and Engineering College of Chemistry Peking University Beijing 100871, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2001年第4期391-397,共7页
The structural and morphological evolution of mono-domains in thin films has been investigated for a series of liquid crystalline (LC) copolyethers. The copolyethers studied were synthesized by the reaction of 1-(4-hy... The structural and morphological evolution of mono-domains in thin films has been investigated for a series of liquid crystalline (LC) copolyethers. The copolyethers studied were synthesized by the reaction of 1-(4-hydroxy-4 ' -biphenylyl)-2-(4-hydroxyl-phenyl)propane (TPP) with 1,7-dibromoheptane and 1,11-undecane at different compositions (coTPPs-7/11). In contrast to the solution-cast thin films without annealing, which exhibit the isotropic homogeneous molecular orientation, mono-domains with a homeotropic alignment were found in coTPP-7/11(5/5) after the thin films were annealed in the high-temperature columnar phase (Phi '). Similar to the nucleation process in polymer crystallization, transmission electron microscopic observations show that small mono-domains appear in the initial stage of annealing, where molecules form a uniaxial in-plane chain orientation. With increasing annealing time, the molecular orientation gradually became tilted with respect to the substrate surface, and finally, a uniaxial homeotropic molecular orientation was achieved after a prolonged annealing time. The lateral size of mono-domains was found to increase continuously with annealing time and grew into a circular shape, indicating an isotropic lateral growth scheme which implies a hexagonal molecular packing proved by the electron diffraction experiments. 展开更多
关键词 main-chain liquid crystalline polymer structure morphology
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Testing Technology of the Main Structure of the Housing Construction Project
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作者 JIANGFu 《外文科技期刊数据库(文摘版)工程技术》 2022年第2期153-156,共4页
When the construction of housing construction project, the quality control of the main structure is very important, only the quality optimization of the main structure, can reduce the variety of accidents caused by st... When the construction of housing construction project, the quality control of the main structure is very important, only the quality optimization of the main structure, can reduce the variety of accidents caused by structural stability, lack of firmness and other reasons. With the progress of technology in the field of housing construction engineering, the main structure testing technology is becoming increasingly mature. In the actual construction process, the main structure testing technology can find structural defects in time and ensure the timeliness and effectiveness of the treatment of structural problems. In the implementation of housing construction projects, each engineering enterprise should choose the appropriate main structure testing technology starting from the requirements and characteristics of the main structure construction of the main structure, so as to ensure the construction quality of the main structure to the greatest extent. 展开更多
关键词 construction engineering main structure TESTING
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Building Main Structure Engineering Construction Technology
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作者 ZHANG Hao 《外文科技期刊数据库(文摘版)工程技术》 2021年第6期267-269,共5页
The construction project in the actual construction process, in order to comprehensively ensure the construction quality, we should strengthen the importance of the main design of the building, and through the applica... The construction project in the actual construction process, in order to comprehensively ensure the construction quality, we should strengthen the importance of the main design of the building, and through the application of standardized construction technology, reasonable control of the construction progress and quality, to ensure the smooth progress of the follow-up work. Based on this, this paper mainly around the importance of the construction of the main structure of the building to launch an analysis, elaborated the technical application countermeasures. 展开更多
关键词 BUILDING main structure engineering construction technology
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Analysis on Construction Technology of Leakage Treatment for Main Structure Engineering of Open-cut Subway Station
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作者 LUOXiaojian 《外文科技期刊数据库(文摘版)工程技术》 2022年第1期049-052,共4页
With the continuous development of urbanization construction, rail transit has received more and more attention. For the current subway station, the main structure of open-cut subway station plays an important role in... With the continuous development of urbanization construction, rail transit has received more and more attention. For the current subway station, the main structure of open-cut subway station plays an important role in it. Therefore, the leakage problem with high frequency should be analyzed in time and dealt with reasonably. In this paper, the construction technology of leakage treatment for the main structure of open-cut subway station is analyzed for reference. 展开更多
关键词 open-cut subway stations main structure engineering water leakage treatment construction technique
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Construction Technology of Rope Saw Cutting in Main Retaining Structure of Some Metro Stations
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作者 LUO Changjiang 《外文科技期刊数据库(文摘版)工程技术》 2021年第5期153-156,共7页
After the construction of the main enclosure of subway station is completed, some concrete structures need to be removed. The traditional construction method is used to solve the problem of damage and noise pollution ... After the construction of the main enclosure of subway station is completed, some concrete structures need to be removed. The traditional construction method is used to solve the problem of damage and noise pollution caused by the finished products of the main structure easily. The construction quality of other main enclosure structures is guaranteed. The technological principle, construction process and safety quality control points of rope saw cutting construction of main retaining structure of subway station are introduced emphatically. 展开更多
关键词 main body of subway station removing enclosure structure cutting of rope saw
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Spatial structural analysis of main saddle for single tower spatial cable self-anchored suspension bridge
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作者 李建慧 李爱群 +1 位作者 袁辉辉 李喜平 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期372-375,共4页
Based on the engineering background of the Jiangxinzhou Bridge in Nanjing, issues related to the spatial main saddle of the self-anchored suspension bridge are studied. The refinement finite element model is establish... Based on the engineering background of the Jiangxinzhou Bridge in Nanjing, issues related to the spatial main saddle of the self-anchored suspension bridge are studied. The refinement finite element model is established by the secondary development technology based on the platform of the general finite element program, and a reasonable load pattern is used in its spatial structural analysis, by which its path of force transference and stress distribution are obtained. Matched with the spatial main cable, the tangency point correction method is also discussed. The results show that the lateral wall stress of the saddle groove is higher than the stress within the wall due to the role of lateral forces in the finished bridge state; the horizontal volume force of the main cable can generate a gradient distributed vertical extrusion pressure on the saddle clamping device and the main saddle body; the geometric nonlinear effect of the self- anchored suspension bridge cable system in the construction process is significant, which can be reflected in the spatial tangent point position of the main cable with the main saddle changes a lot from free cable to finished cable. 展开更多
关键词 self-anchored suspension bridge finite element main saddle spatial cable structural design
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The Design of Water-reusing Network with a Hybrid Structure Through Mathematical Programming 被引量:4
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作者 刘永忠 段海涛 冯霄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期1-10,共10页
A new design method for a water-reusing network, with a hybrid structure, to reduce the complexity of the network and to minimize freshwater consumption, is proposed. The unique feature of the methodology proposed .i... A new design method for a water-reusing network, with a hybrid structure, to reduce the complexity of the network and to minimize freshwater consumption, is proposed. The unique feature of the methodology proposed .in this article is to control the complexity of the water network by regulation of the control number in a water-reusing system. It combines the advantages of a conventional water-reusing network and a water-reusing net work with internal water mains. To illustrate the proposed method, a single contaminant system and a multiple contaminant system serve as examples of the problems. 展开更多
关键词 water-reusing network internal water main hybrid structure OPTIMIZATION
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Structural,Kinematic and Geochronological Study of the Main Tianshan Shear Zone in the Borohoro Ranges,NW China 被引量:1
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作者 LIU Tianlun CHEN Siyu +5 位作者 ZHANG Bo CAI Keda HAN Baofu QU Junfeng GUO Lei WANG Meng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第5期1431-1455,共25页
The western segment of the Main Tianshan shear zone(MTSZ)branches into three major dextral strike-slip shear zones in the Borohoro Ranges,northwestern China.Mylonitic rocks within these zones exhibit vertical foliatio... The western segment of the Main Tianshan shear zone(MTSZ)branches into three major dextral strike-slip shear zones in the Borohoro Ranges,northwestern China.Mylonitic rocks within these zones exhibit vertical foliations,subhorizontal lineations,and dextral kinematics.The microstructures and CPO patterns of calcite and quartz in the tectonites suggest shearing at temperatures of 200℃ to 500℃ or above.The amount of dextral displacement along the zones is less than 100 km.LA-ICP-MS U-Pb dating of zircons from some pre-kinematic granites gave ages of 364-325 Ma and 316 Ma,and zircons from a syn-kinematic leucogranite gave an age of 291 Ma.We propose that dextral shearing along the MTSZ started in the earliest Permian.Our data indicate that collision between the Yili and Junggar plates might have finished before 325 Ma or 316 Ma,with a tectonic transformation from 325 Ma to 300 Ma,resulting in intracontinental transpression from 300 Ma or 291 Ma.We suggest that the formation of the Kazakhstan orocline(KO)took place in two stages,with the early stage of bending driven by convergence related to oblique subduction,and the late stage possibly associated with lateral disarticulation as a result of the dextral strike-slip shear zones. 展开更多
关键词 structural geology geochronology dextral shearing CPO pattern Late Paleozoic main Tianshan Shear Zone Yili-North Tianshan
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Pore structure characteristics of the relative water-resisting layer on the top of the Ordovician in Longgu Coal Mine 被引量:3
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作者 Rong Huren Bai Haibo 《International Journal of Mining Science and Technology》 SCIE EI 2014年第5期657-661,共5页
In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture a... In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture and pore structure features of the strata, and identified the main channels which govern the permeability and water-resisting ability of the strata. The permeability of the upper, central and lower strata shows as 2.0504 × 10^-3-2.782762× 10^-3, 4.1092 × 10^-3 -7.3387 × 10^-3 and 2.0891 ×10^-3-3.2705 × 10-3 μm^2, respectively, and porosity of that is 0.6786-0.9197%, 0.3109-0.3951% and 0.9829-1.8655%, respectively. The results indicate that: (I) the main channels of the relative water-resisting layer are the pore throats with a diameter more than 6 μm; (2) the major proportion of pore throats in the vertical flow channel and the permeability first increases and then sharply decreases; (3) the fractures occurring from the top to 20 m in depth of the strata were filled and there occurred almost no fracture under the depth of 40 m; and (4) the ratio of turning point of the main flow channel in the strata on top of Ordovician can be used to confirm the thickness of filled water-resisting lavers. 展开更多
关键词 Relative water-resisting layer Filling effect main channels of seepage Pore structure
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Pore-throat structure characteristics and its impact on the porosity and permeability relationship of Carboniferous carbonate reservoirs in eastern edge of Pre-Caspian Basin 被引量:1
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作者 LI Weiqiang MU Longxin +8 位作者 ZHAO Lun LI Jianxin WANG Shuqin FAN Zifei SHAO Dali LI Changhai SHAN Fachao ZHAO Wenqi SUN Meng 《Petroleum Exploration and Development》 2020年第5期1027-1041,共15页
Carboniferous carbonate reservoirs at the eastern edge of the Pre-Caspian Basin have undergone complex sedimentation,diagenesis and tectonism processes,and developed various reservoir space types of pores,cavities and... Carboniferous carbonate reservoirs at the eastern edge of the Pre-Caspian Basin have undergone complex sedimentation,diagenesis and tectonism processes,and developed various reservoir space types of pores,cavities and fractures with complicated combination patterns which create intricate pore-throats structure.The complex pore-throat structure leads to the complex porosity-permeability relationship,bringing great challenges for classification and evaluation of reservoirs and efficient development.Based on the comprehensive analysis on cores,thin sections,SEM,mercury intrusion,routine core analysis and various tests,this paper systematically investigated the features and main controlling factors of pore-throats structure and its impact on the porosity-permeability relationship of the four reservoir types which were pore-cavity-fracture,pore-cavity,pore-fracture and pore,and three progresses are made.(1)A set of classification and descriptive approach for pore-throat structure of Carboniferous carbonate reservoirs applied to the eastern edge of the Pre-Caspian Basin was established.Four types of pore-throat structures were developed which were wide multimodal mode,wide bimodal mode,centralized unimodal mode and asymmetry bimodal mode,respectively.The discriminant index of pore-throat structure was proposed,realizing the quantitative characterization of pore-throat structure types.(2)The microscopic heterogeneity of pore reservoir was the strongest and four types of pore-throat structures were all developed.The pore-fracture and pore-cavity-fracture reservoirs took the second place,and the microscopic heterogeneity of pore-cavity reservoir was the weakest.It was revealed that the main controlling factor of pore-throat structure was the combination patterns of reservoir space types formed by sedimentation,diagenesis and tectonism.(3)It was revealed that the development of various pore-throat structure types was the important factor affecting poroperm relationship of reservoirs.The calculation accuracy of permeability of reservoirs can be improved remarkably by subdividing the pore-throat structure types.This study deepens the understanding of pore-throat structure of complicated carbonate reservoirs,and is conducive to classification and evaluation,establishment of precise porosity-permeability relationship and highly efficient development of carbonate reservoirs. 展开更多
关键词 Pre-Caspian Basin CARBONIFEROUS carbonate reservoir pore-throat structure main controlling factors porosity-permeability relationship
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Modeling of 3D-structure for regular fragments of low similarity unknown structure proteins
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作者 彭志红 Chen Jie Lin Xiwen Sang Yanchao 《High Technology Letters》 EI CAS 2007年第4期431-435,共5页
Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular ... Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular fragments (α-Helices, β-Strands) of such proteins by the protein secondary structure prediction software, the Basic Local Alignment Search Tool (BLAST) and the side chain construction software SCWRL3. First, the protein secondary structure prediction software is adopted to extract secondary structure fragments from the unknown structure proteins. Then, regular fragments are regulated by BLAST based on comparative modeling, providing main chain configurations. Finally, SCWRL3 is applied to assemble side chains for regular fragments, so that 3D-structure of regular fragments of low similarity unknown structure protein is obtained. Regular fragments of several neurotoxins are used for test. Simulation results show that the prediction errors are less than 0.06nm for regular fragments less than 10 amino acids, implying the simpleness and effectiveness of the proposed method. 展开更多
关键词 low similarity unknown structure regular segment 3D-structure modeling main chain confonnation side chain assembly
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Basic Structural Forms of Main Roof
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《岩石力学与工程学报》 EI CAS CSCD 1995年第S1期425-437,共13页
BasicStructuralFormsofMainRoofByJiangFuxing;SongZhenqiandSongYang(ShandongInstituteofCoalMiningandTechnology... BasicStructuralFormsofMainRoofByJiangFuxing;SongZhenqiandSongYang(ShandongInstituteofCoalMiningandTechnology,Taian271019)SUMM... 展开更多
关键词 Basic structural Forms of main Roof
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Analysis of Design Points and Development Trend of Prefabricated Building Structure System
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作者 XUEJing ZHANGDonghui 《外文科技期刊数据库(文摘版)工程技术》 2022年第7期040-043,共4页
Nowadays, China is promoting the urbanization construction in an all-round way, which puts forward higher requirements for the quality and structure of construction projects. In the past, the control methods caused gr... Nowadays, China is promoting the urbanization construction in an all-round way, which puts forward higher requirements for the quality and structure of construction projects. In the past, the control methods caused great pollution to the natural environment, and extensive control also caused various problems in the quality of construction projects. In recent years, many new technologies and methods have been applied to the architectural design industry in China, especially the application of BIM technology in the design of prefabricated buildings, which has attracted the general attention of technical experts and staff. It can not only improve the efficiency of architectural design, but also ensure the quality of architectural engineering. This paper explores the design and application of prefabricated buildings, hoping to provide reference for practitioners. 展开更多
关键词 prefabricated buildings structure design TREND main points
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Discussion on Key Points of Building Steel Structure Construction Technology
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作者 ZHAOChengwei 《外文科技期刊数据库(文摘版)工程技术》 2022年第6期144-148,共5页
Scientific and reasonable application of steel structures in construction projects can not only promote the rapid development of the construction industry, but also help to improve the economic benefits of other indus... Scientific and reasonable application of steel structures in construction projects can not only promote the rapid development of the construction industry, but also help to improve the economic benefits of other industries in our country. Therefore, relevant construction engineering units must fully grasp the technical points of steel structure construction. 展开更多
关键词 house building steel structure construction technology main points
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顺北—顺南地区深层碳酸盐岩走滑断裂结构特征及其形成的主控因素分析
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作者 吴孔友 杨言军 +2 位作者 刘寅 洪梅 汪必峰 《浙江大学学报(理学版)》 北大核心 2026年第1期97-108,共12页
塔里木盆地顺北—顺南地区的深层碳酸盐岩走滑断裂发育对下古生界碳酸盐岩具有明显的控藏作用。由于碳酸盐岩岩性脆且致密,走滑断裂水平错动作用必然导致其形成独特的结构特征。针对顺北—顺南地区的深层碳酸盐岩走滑断裂体系,基于现有... 塔里木盆地顺北—顺南地区的深层碳酸盐岩走滑断裂发育对下古生界碳酸盐岩具有明显的控藏作用。由于碳酸盐岩岩性脆且致密,走滑断裂水平错动作用必然导致其形成独特的结构特征。针对顺北—顺南地区的深层碳酸盐岩走滑断裂体系,基于现有研究成果,通过野外相似露头踏勘,结合地震、岩心等资料,利用高精度三维地震数据体走滑断裂精细刻画、地震属性体走滑断裂体系识别、物理模拟实验、应力场数值模拟等技术方法,分析了走滑断裂的结构特征,并对其形成的主控因素进行了归纳总结。研究发现,顺北—顺南地区深层走滑断裂的空间结构主要表现为“平面沿走向分段、剖面分层变形”的特征,在平面上主断裂可划分为张扭段、压扭段、直立段,三者交替出现,在剖面上以中下奥陶统顶界面(T74)为界,将断裂分为深层和浅层系统,深、浅层断裂纵向叠置,分层特征明显。将内部结构划分为“滑动破碎带—诱导裂缝带”二元结构,二者差异明显,特征相异。多期构造活动、应力分布、断裂活动强度、地层岩性和后期的胶结充填作用均可影响断裂带的二元结构。 展开更多
关键词 塔里木盆地 碳酸盐岩 走滑断裂 结构特征 控制因素
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基于着生藻类完整性指数的汉江干流健康评价
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作者 郑紫岳 闫龙 +3 位作者 张尚弘 王乐 吴雪 方青青 《人民长江》 北大核心 2026年第1期131-138,共8页
为调查汉江干流着生藻类群落现状并评价汉江流域水生态系统的健康状况,基于2023年5月(春季)和2024年11月(秋季)在汉江干流的采样数据,通过冗余分析(RDA)法研究汉江干流着生藻类群落结构特征,应用着生藻类生物完整性指数(P-IBI)进行河流... 为调查汉江干流着生藻类群落现状并评价汉江流域水生态系统的健康状况,基于2023年5月(春季)和2024年11月(秋季)在汉江干流的采样数据,通过冗余分析(RDA)法研究汉江干流着生藻类群落结构特征,应用着生藻类生物完整性指数(P-IBI)进行河流健康评价,并利用Pearson相关性法分析影响河流健康的相关环境因子。结果显示:(1)两次采样共采集到着生藻类159种,其中硅藻门98种,占比61.63%。(2)春季着生藻类群落的主要影响因子为总磷、总氮、化学需氧量和电导率,秋季主要影响因子为总氮、pH和流速。(3)春季汉江流域P-IBI平均得分为3.923,健康状况为中等;秋季平均得分为5.679,健康状况为良好。(4) Pearson相关性分析表明,春季P-IBI值与总氮呈极显著正相关,与电导率呈显著负相关,与pH和流速呈显著正相关;秋季P-IBI值与流速呈显著正相关。(5)汉江上游健康状况较好,中下游较差,两者存在较大差异。 展开更多
关键词 着生藻类 河流健康评价 生物完整性指数 冗余分析 群落结构 汉江干流
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