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Nonlinear Analysis of Structures by Total Potential Optimization Using Metaheuristic Algorithms (TPO/MA)
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作者 Yusuf Cengiz Toklu 《Journal of Civil Engineering and Architecture》 2023年第3期152-160,共9页
Structural analysis problems can be formulized as either root finding problems,or optimization problems.The general practice is to choose the first option directly or to convert the second option again to a root findi... Structural analysis problems can be formulized as either root finding problems,or optimization problems.The general practice is to choose the first option directly or to convert the second option again to a root finding problem by taking relevant derivatives and equating them to zero.The second alternative is used very randomly as it is and only for some simple demonstrative problems,most probably due to difficulty in solving optimization problems by classical methods.The method called TPO/MA(Total Potential Optimization using Metaheuristic Algorithms)described in this study successfully enables to handle structural problems with optimization formulation.Using metaheuristic algorithms provides additional advantages in dealing with all kinds of constraints. 展开更多
关键词 TPO/MA structural analysis NONLINEAR TRUSS metaheuristics algorithms
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Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation 被引量:1
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作者 Jingjing Liang Meina Zhang +6 位作者 Xiaohan Li Yuan Yue Xiaowei Wang Mengzhen Han Tianli Yue Zhouli Wang Zhenpeng Gao 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期421-433,共13页
Plant-based fermentations provide an untapped source for novel biotechnological applications.In this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus edodes.Polysaccharides were... Plant-based fermentations provide an untapped source for novel biotechnological applications.In this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus edodes.Polysaccharides were extracted from fermented and non-fermented L.edodes and purified via DEAE-52 and Sephadex G-100.The components designated F-LEP-2a and NF-LEP-2a were analyzed by FT-IR,HPGPC,HPAEC,SEM,GC-MS and NMR.The results revealed that probiotic fermentation increased the molecular weight from 1.16×10^(4) Da to 1.87×10^(4) Da and altered the proportions of glucose,galactose and mannose,in which glucose increased from 45.94%to 48.16%.Methylation analysis and NMR spectra indicated that F-LEP-2a and NF-LEP-2a had similar linkage patterns.Furthermore,their immunomodulatory activities were evaluated with immunosuppressive mice.NF-LEP and F-LEP improved immune organ indices,immunoglobulin(Ig G and Ig M)and cytokines concentrations;restored the antioxidation capacity of liver;and maintained the balance of gut microbiota.F-LEP displayed better moderating effects on the spleen index,immunoglobulin,cytokines and the diversity of gut microbiota than NF-LEP(200,400 mg/kg).Our study provides an efficient and environment-friendly way for the structural modification of polysaccharides,which helps to enhance their biological activity and promote their wide application in food,medicine and other fields. 展开更多
关键词 Lentinus edodes polysaccharide Lactobacillus fermentum fermentation structural analysis Immunoregulatory activity Nuclear magnetic resonance
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Seismic response of a mid-story isolated structure considering SSI in mountainous areas under long-period earthquakes
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作者 Wan Feng Qin Shengwu +7 位作者 Liu Dewen Zhao Tiange Zheng Yanping Shan Hang Li Zhiang Peng Fusong Xu Jingran Lei Min 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期151-161,共11页
At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is es... At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures. 展开更多
关键词 SSI in mountainous areas long-period earthquakes mid-story isolated structure structural dynamic analysis
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Early Cretaceous Thrust and Nappe Tectonics in North Qilian Shan,Northern Tibetan Plateau:Evidence from Field Mapping,Geochronology,and Deep Structural Analysis 被引量:1
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作者 HAN Lele DING Weicui +9 位作者 CHEN Xuanhua SHAO Zhaogang ZHANG Da XIAO Yongjun HE Chengguang WANG Zengzhen LI Bing ZHANG Yiping XU Shenglin WANG Ye 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第4期1058-1077,共20页
The North Qilian Shan fold and thrust belt,located at the northern Tibetan Plateau and southern margin of the Hexi Corridor,is a key tectonic unit to decode the formation and expansion of the plateau.Previous studies ... The North Qilian Shan fold and thrust belt,located at the northern Tibetan Plateau and southern margin of the Hexi Corridor,is a key tectonic unit to decode the formation and expansion of the plateau.Previous studies emphasize the Cenozoic deformation due to the far-field response to the Indo-Asian collision,but the Mesozoic deformations are poorly constrained in this area.We conducted detailed field mapping,structural analysis,geochronology,and structural interpretation of deep seismic reflectional profiling and magnetotelluric(MT)sounding,to address the superposed results of the Mesozoic and Cenozoic deformation.The results recognized the North Qilian thrust and nappe system(NQTS),the root and the frontal belt are the North Qilian thrust(NQT),and the Yumu Shan klippe(YK),respectively.The middle belt is located between the NQT and the YK.Monzonitic granite zircon U-Pb dating from the middle belt yields an age of ca.415 Ma,which is similar to south NQT.The thrusting displacement is estimated at ca.48 km by structural interpretation of deep profiles.The timing is constrained in the early stage of the Early Cretaceous by the formation of simultaneous growth strata.We suggest that the NQTS has resulted from the far-field effect of the Lhasa-Qiangtang collision,and the Yumu Shan is uplifted by the superposed Cenozoic deformation. 展开更多
关键词 GEOCHRONOLOGY structural analysis seismic reflectional and MT profiling Early Cretaceous North Qilian thrust and nappe system Tibetan Plateau
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An Educational GUI-Based Software for Dynamic Analysis of Framed Structural Models
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作者 Claudio H. B. Resende Pedro C. Lopes +2 位作者 Rafael L. Rangel Luis F. Paullo Muñoz Luiz F. Martha 《Journal of Software Engineering and Applications》 2023年第7期265-286,共22页
This paper introduces a new version of the open-source educational software, LESM (Linear Elements Structure Model), developed in MATLAB for structural analysis of one-dimensional models such as frames, trusses, and g... This paper introduces a new version of the open-source educational software, LESM (Linear Elements Structure Model), developed in MATLAB for structural analysis of one-dimensional models such as frames, trusses, and grillages. The updated program includes dynamic analysis, which incorporates inertial and damping effects, time-dependent load conditions, and a transient solver with multiple time integration schemes. The software assumes small displacements and linear-elastic material behavior. The paper briefly explains the theoretical basis for these developments and the reorganization of the source code using Object-Oriented Programming (OOP). The updated Graphical User Interface (GUI) allows interactive use of dynamic analysis features and displays new results such as animations, envelope diagrams of internal forces, phase portraits, and the response of degrees-of-freedom in time and frequency domain. The new version was used in a structural dynamics course, and new assignments were elaborated to improve students’ understanding of the subject. 展开更多
关键词 structural analysis structural Dynamics Educational Software MATLAB Graphical User Interface
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Suboptimal Rayleigh damping coefficients in seismic analysis of viscously-damped structures 被引量:7
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作者 Pan Danguang Chen Genda Wang Zuocai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第4期653-670,共18页
An optimization method for the consistent evaluation of two Rayleigh damping coefficients is proposed. By minimizing an objective function such as an error term of the peak displacement of a structure, the two coeffic... An optimization method for the consistent evaluation of two Rayleigh damping coefficients is proposed. By minimizing an objective function such as an error term of the peak displacement of a structure, the two coefficients can be determined with response spectral analysis. The optimization method degenerates into the conventional method used in current practices when only two modes of vibration are included in the objective function. Therefore, the proposed method with all significant modes included for simplicity in practical applications results in suboptimal damping coefficients. The effects of both spatial distribution and frequency content of excitations as well as structural dynamic characteristics on the evaluation of Rayleigh damping coefficients were investigated with a five-story building structure. Two application examples with a 62-story high-rise building and a 840 m long cable-stayed bridge under ten earthquake excitations demonstrated the accuracy and effectiveness of the proposed method to account for all of the above effects. 展开更多
关键词 Rayleigh damping response spectral analysis structural dynamics structural analysis optimization method
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LOCAL FLEXIBILITY BEHAVIOR OF TUBULAR JOINTS AND ITS EFFECT ON GLOBAL ANALYSIS OF TUBULAR STRUCTURES 被引量:3
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作者 Yang, Lixian Chen, Tieyun Wu, Shuiyun 《China Ocean Engineering》 SCIE EI 1990年第4期371-384,共14页
In the tubular frames with simple joints, the joints may show considerable local flexibility, which causes excessive deformation and affects internal force distributions. It is useful and important to study turbular j... In the tubular frames with simple joints, the joints may show considerable local flexibility, which causes excessive deformation and affects internal force distributions. It is useful and important to study turbular joint flexibility as well as the effect of joint local flexibility on the global behavior of tubular structure for the design and building of offshore platforms. A new method for computing the stiffness coefficients of simple tubular joints is developed in this paper based on two previous computing models. According to this method, the local flexibility of T, Y, TY tubular joints are computed. This method has merits of clear physical sense, simplicity of computations and less c.p.u. time. The effect of flexibility of tubular joints on the global behavior of framed tubular structures is investigated by comparing the computed results of tubular structures with flexible tubular joints with those with rigid connections. The comparison shows that the consideration of local flexibility of tubular joints and its effect on the stress analysis of offshore structures has its practical significance. 展开更多
关键词 Offshore structures structural analysis Stresses COMPUTATION
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Genetic diversity and population structure analysis of 161 broccoli cultivars based on SNP markers 被引量:3
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作者 Jingjing Huang Yumei Liu +8 位作者 Fengqing Han Zhiyuan Fang Limei Yang Mu Zhuang Yangyong Zhang Honghao Lv Yong Wang Jialei Ji Zhansheng Li 《Horticultural Plant Journal》 SCIE CSCD 2021年第5期423-433,共11页
To better understand the genetic diversity and population structure of broccoli cultivars planted in China,a total of 161 representative broccoli cultivars in the past 25 years were collected and analysed based on sin... To better understand the genetic diversity and population structure of broccoli cultivars planted in China,a total of 161 representative broccoli cultivars in the past 25 years were collected and analysed based on single nucleotide polymorphism(SNP)markers.Ten pairs of primers with good polymorphism and high resolution were screened from 315 pairs of SNP primers by 3 broccoli accessions(inbred lines)with different phenotypes and maturity.The 10 pairs of SNP primers were selected,producing 78 alleles.The diversity analysis indicated that the polymorphism information content(PIC)of SNP primer ranged from 0.64 to 0.90.The observed number of alleles(Na)was 2.00,the effective number of alleles(Ne)was 1.11–2.00,the Nei’s gene diversity(H)was 0.10–0.50,and Shannon information index(I)was 0.20–0.70 using PopGene32 software.The clustering results showed that the 161 broccoli cultivars could be divided into 4 major subgroups(A,B,C and D),foreign cultivars were all assigned to subgroup A,and domestic cultivars were assigned to 3 subgroups of B,C,and D.This study indicated that some domestic cultivars and foreign cultivars were similar in genetic background,but most domestic cultivars were still different from the Japanese cultivars.When K=2,the population structure result presented that 161 broccoli cultivars could be divided into 1 simple group(2 groups)and 1 mixed group.When Q≥0.6,143(88.82%)broccoli cultivars belonged to the simple groups.In simple groups 68(42.24%)broccoli cultivars of group 1 were derived from Japan,the United States,Switzerland,the Netherlands,China-Taiwan,and China-Mainland;75(46.58%)broccoli cultivars belonged to group 2;when Q<0.6,18(11.18%)broccoli cultivars belonged to the mixed groups.This study is helpful to understand the diversity and resolution of broccoli cultivars from worldwide,which is beneficial to plant breeding and materials innovation.And meanwhile,this result is also used for construction of broccoli fingerprint serving for cultivar identification. 展开更多
关键词 BROCCOLI Genetic diversity Population structure analysis FINGERPRINT SNP
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Structure Analysis of the Complete Mitochondrial Genome in Cultivation Variety ‘Rongfu’ 被引量:2
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作者 ZHANG Jing LI Ning ZHANG Zhifeng LIU Tao 《Journal of Ocean University of China》 SCIE CAS 2011年第4期351-356,共6页
In this report,complete mitochondrial genome sequences of Laminaria cultivation variety 'Rongfu' were obtained.The results showed the length of circular molecule of mtDNA was 37 638 bp(64.7% A+T),encoding thre... In this report,complete mitochondrial genome sequences of Laminaria cultivation variety 'Rongfu' were obtained.The results showed the length of circular molecule of mtDNA was 37 638 bp(64.7% A+T),encoding three rRNAs(23S,16S and 5S),25 tRNAs,35 known mitochondrial proteins and 3 ORFs.Sequence alignment indicated its mtDNA genome was very similar to that of Laminaria japonica.Phylogenetic trees inferred from concatenated 30 mitochondrial genes showed that 'Rongfu',Laminaria japon-ica,Laminaria longipedalis,Laminaria diabolica,Laminaria religiosa and Laminaria ochotensis clustered together.In addition,compared with mitochondrial genome of L.japonica,'Rongfu' mtDNA lacked a non-coding region of 19 nucleotides,which was located between rRNA small subunit gene 3(rps3)and rRNA small subunit gene 9(rps9).Seven cultivation varieties of China were divided into two groups based on this non-coding region which was absent in 'Rongfu','Fujian' and 'Sanhai' while present in 'Ailunwan','Dongfang No.2','Dongfang No.3' and 'Zaohoucheng'.So this variation can be used in germplasm identification of cultivation variety. 展开更多
关键词 LAMINARIA mitochondrial DNA structure analysis phylogenetic relationship germplasm identification
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PHASE EXTENSION AND STRUCTURE ANALYSIS BY THE MAXIMUM ENTROPY METHOD 被引量:1
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作者 G.B.Hu and Q.B.Yang (Department of Physics, Xiangtan University, Xiangtan 411105, China)(Beijing Laboratory of Electron Microscopy, Center for Condensed Matter Physics, The Chinese Academy of Sciences, P. O. Box 2724, Beijing 100080, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第4期241-254,共14页
Excellent results are obtained in structure analysis with jew phases of structure factors by the maximum-entropy method (MEM) for CaGaN PbCO3 and ReBe22 single crystals. The computation time and memory space are minim... Excellent results are obtained in structure analysis with jew phases of structure factors by the maximum-entropy method (MEM) for CaGaN PbCO3 and ReBe22 single crystals. The computation time and memory space are minimized by symmetry operations so that structure analysis by the MEM can be carried out with a personal computer. 展开更多
关键词 maximum entropy method structure analysis phase extension symmetry
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Automatic Persian Text Summarization Using Linguistic Features from Text Structure Analysis 被引量:1
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作者 Ebrahim Heidary Hamïd Parvïn +2 位作者 Samad Nejatian Karamollah Bagherifard Vahideh Rezaie 《Computers, Materials & Continua》 SCIE EI 2021年第12期2845-2861,共17页
With the remarkable growth of textual data sources in recent years,easy,fast,and accurate text processing has become a challenge with significant payoffs.Automatic text summarization is the process of compressing text... With the remarkable growth of textual data sources in recent years,easy,fast,and accurate text processing has become a challenge with significant payoffs.Automatic text summarization is the process of compressing text documents into shorter summaries for easier review of its core contents,which must be done without losing important features and information.This paper introduces a new hybrid method for extractive text summarization with feature selection based on text structure.The major advantage of the proposed summarization method over previous systems is the modeling of text structure and relationship between entities in the input text,which improves the sentence feature selection process and leads to the generation of unambiguous,concise,consistent,and coherent summaries.The paper also presents the results of the evaluation of the proposed method based on precision and recall criteria.It is shown that the method produces summaries consisting of chains of sentences with the aforementioned characteristics from the original text. 展开更多
关键词 Natural language processing extractive summarization linguistic feature text structure analysis
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FUNDAMENTAL OF DYNAMICAL ANALYSIS OF THE BLAST-RESISTANT UNDERGROUND STRUCTURES 被引量:1
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作者 赵玉祥 宋熙太 钱尔旋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第5期407-415,共9页
In this paper, the generalized variational principle of dynamic analysis for the blast-resistant underground structures is established, and the corresponding generalized functional of elastoplastic analysis for underg... In this paper, the generalized variational principle of dynamic analysis for the blast-resistant underground structures is established, and the corresponding generalized functional of elastoplastic analysis for underground structures is derived, and the generalized variational principle of nonconservative system is given, thus the fundamental of dynamical analysis for underground structures to resist blast is proposed. Finally, for the underground cylindrical structure to resist blast, dynamical calculations are made, and compared with the test results. 展开更多
关键词 generalized variational principle dynamical analysis of structure elastoplastic analysis blast-resistant underground structure
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Analysis of the Ore-Controlling Structure of Ductile Shear Zone Type Gold Deposit in Southern Beishan Area, Gansu, Northwest China 被引量:3
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作者 陈柏林 吴淦国 +3 位作者 叶德金 刘晓春 舒斌 杨农 《Journal of China University of Geosciences》 SCIE CSCD 2007年第1期30-38,共9页
The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beisha... The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt. The controls of the ductile shear zone on gold deposits are as follows. (1) The regional distribution of gold deposits (and gold spots) is controlled by the ductile shear zone. (2) The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and control the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. (3) Compresso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. (4) Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R'-type and T-type ones. (5) Dynamic differen- tiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming materials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. (6) There is a negative correlation between the gold abundance and susceptibility anlsotropy (P) of the altered mylonlte samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits. 展开更多
关键词 analysis of ore.controlling structure gold deposit ductile shear zone Beishanarea of Gansu Northwest China
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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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One Novel 2D Co(Ⅱ) Polymer with 1,2,3-Triazole Derivative: Crystal Structure, Fluorescence and Hirshfeld Surface Analysis 被引量:1
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作者 冯超 黄欢欢 +1 位作者 张舵 赵红 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第9期1376-1382,共7页
One new polymer [Co(L)(H2O)2]n(1) was synthesized by 4-(ethoxycarbonyl)-5-methyl-1H-1,2,3-triazole-1-carboxylic acid(Emtc) under the in situ solvent thermal reaction(H2L = 1-(carboxymethyl)-5-methyl-1H-1,... One new polymer [Co(L)(H2O)2]n(1) was synthesized by 4-(ethoxycarbonyl)-5-methyl-1H-1,2,3-triazole-1-carboxylic acid(Emtc) under the in situ solvent thermal reaction(H2L = 1-(carboxymethyl)-5-methyl-1H-1,2,3-triazole-4-carboxylic acid). The title complex performs a wave-like 2D framework and the ligand H2L demonstrates the coordination mode as μ4-η-2:η-1η-1:η-1. The crystal structure has been established by single-crystal X-ray diffraction, and characterized by FT-IR. Fluorescent property was investigated in this work. Hirshfeld surface analysis has also been carried out on 1, and obvious main intermolecular interactions are observed. 展开更多
关键词 1H-1 2 3-triazole acid derivative crystal structure fluorescence Hirshfeld surface analysis
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ANALYSIS OF DYNAMIC STABILITY OF SUBMERGED STRUCTURE 被引量:2
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作者 Qu Naisi , Yang Chunqiu and Tao Zhengguo Associate Professor, Dalian University of Technology, Dalian, Engineer, Wuxi 706 Research Institute, Wuxi 《China Ocean Engineering》 SCIE EI 1990年第2期209-220,共12页
The submerged structure is basically a large three-dimensional structure of few statically redundant members. The structure is subjected to vertical dead and live loads in addition to the wave forces. An analysis of d... The submerged structure is basically a large three-dimensional structure of few statically redundant members. The structure is subjected to vertical dead and live loads in addition to the wave forces. An analysis of dynamic stability of the submerged structure without damping has been made by J. Thomas and Abbas (1980). In this paper the analyses of dynamic stability of the sumberged structure with damping are conducted. The case structure with damping is more complicated 'than the case without it. According to the principle of perturbation, a new model for dynamic stability calculation in consideration of damping effect is developed. In this paper, the formulas are deduced, the computational program is compiled, the practical examples are analysed, and this problem is solved very satisfactorily. The computational results show that the shape and value of the regions of dynamic instability can be changed significantly by damping. So only by considering damping can the property of dynamic stability of the submerged structure be reflected correctly. 展开更多
关键词 analysis OF DYNAMIC STABILITY OF SUBMERGED structure
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Test analysis of detection of damage to a complicated spatial model structure 被引量:2
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作者 Long-He Xu Zhong-Xian Li Jia-Ru Qian 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第3期399-405,共7页
A two-stage damage detection approach is proposed and experimentally demonstrated on a complicated spatial model structure with a limited number of measurements. In the experiment,five known damage patterns,including ... A two-stage damage detection approach is proposed and experimentally demonstrated on a complicated spatial model structure with a limited number of measurements. In the experiment,five known damage patterns,including 3 brace damage cases and 2 joint damage cases,were simulated by removing braces and weakening beam鈥揷olumn connections in the structure. The limited acceleration response data generated by hammer impact were used for system identification,and modal parameters were extracted by using the eigensystem realization algorithm. In the first stage,the possible damaged locations are determined by using the damage index and the characteristics of the analytical model itself,and the extent of damage for those substructures identified at stage I is estimated in the second stage by using a second-order eigen-sensitivity approximation method. The main contribution of this paper is to test the two-stage method by using the real dynamic data of a complicated spatial model structure with limited sensors. The analysis results indicate that the two-stage approach is ableto detect the location of both damage cases,only the severity of brace damage cases can be assessed,and the reasonable analytical model is critical for successful damage detection. 展开更多
关键词 Damage detection. Complicated structure. Two-stage approach - Eigen-sensitivity analysis. Joint dam- age
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PHYSICAL VALUE MAPPING ALGORITHM OF MESH IN FINE CAE ANALYSIS OF AUTOMOBILE BODY STRUCTURE 被引量:2
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作者 Hu Ping Gong Kejia Bao Yidong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期338-341,共4页
A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from... A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from the mesh of the product to the mesh of the stamped part will be adopted. At the same time, the search process is divided into two steps: entire search (ES) and local search (LS), which improve the searching efficiency. The searching area is enlarged to avoid missing projection elements in ES process. An arc-length method is introduced in LS process. The validity is confirmed by the results of the complex industry-forming product. 展开更多
关键词 Fine CAE analysis of auto body structure Finite element mesh Arc method Physical value mapping
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Complex Seismic Focus Structure and Earthquake-Triggered Landslide Distribution:Analysis of the 2014 Ludian M_w6.1 Earthquake in Yunnan 被引量:3
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作者 CHEN Xiaoli LIU Chunguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期733-734,共2页
Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Becau... Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Because the suspected seismogenic faults on the surface, distribution of aftershocks and focal mechanism solutions are not consistent, it remains difficult to determine what is the real causal fault or seismogenic structure for this event. Actually, it may imply the complicity of the seismic source at depth. In addition, the distribution of the co- seismic landslides also exhibits some diffusion that is different from general eases, likely associated with the seismic focus structure. 展开更多
关键词 Complex Seismic Focus structure and Earthquake-Triggered Landslide Distribution:analysis of the 2014 Ludian M_w6.1 Earthquake in Yunnan
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Characterization and structure analysis of the heterosolvate of erythromycin thiocyanate
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作者 Yuanjie Li Qiuxiang Yin +5 位作者 Meijing Zhang Ying Bao Baohong Hou Jingkang Wang Jiting Huang Ling Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第4期268-274,共7页
Erythromycin thiocyanate is widely used for the production of other macrolide antibiotics. In this work, a novel heterosolvate of this pharmaceutical compound has been obtained and characterized for the first time, wh... Erythromycin thiocyanate is widely used for the production of other macrolide antibiotics. In this work, a novel heterosolvate of this pharmaceutical compound has been obtained and characterized for the first time, which was transformed from the dihydrate form in the acetone solvent through evaporation crystallization. Thermal behavior together with compositional analysis revealed that both water and acetone molecules participated in the formation of the crystal lattice which is rarely reported before. The general chemical name of the heterosolvate may be defined as erythromycin thiocyanate sesquihydrate hemiacetonate. Furthermore, studies on solid-state spectral analysis provided strong evidence of intermolecular hydrogen bonds in heterosolvate crystals. According to the crystal structure determined by single crystal X-ray diffraction, the formation mechanism of the heterosolvate is proposed in which strong multihydrogen bondings between water and solute molecules form the layer structure. While acetone molecules form single-hydrogen bonds with solutes and reside in channels between layers. This well explains why acetone solvent is easy to escape from the crystal structure during desolvation. 展开更多
关键词 Erythromycin thiocyanate Heterosolvate structure analysis CRYSTALLIZATION Thermodynamic properties TRANSITION
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