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Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation 被引量:2
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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 被引量:1
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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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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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Analysis of the Protein Structure and Function of HpaG_(Xoo) 被引量:2
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作者 任秀艳 冯雪 +1 位作者 侯志敏 张倩倩 《Agricultural Science & Technology》 CAS 2010年第2期12-14,75,共4页
[Objective] The study was to analyze the structure and function of HpaGXoo and the relationship between the two.[Method] Some related bioinformatics analysis software on internet such as NPSA,Swiss-Model,SAPS and Inte... [Objective] The study was to analyze the structure and function of HpaGXoo and the relationship between the two.[Method] Some related bioinformatics analysis software on internet such as NPSA,Swiss-Model,SAPS and InterPro Scan were adopted to analyze the structure and predict its function.[Result] HpaGXoo consists of 139 amino acids,and has many alpha-helical and coiled structure,no signal peptide on N-terminal and no transmembrane structure.It locates in bacterial cytoplasm.[Conclusion] The study will lay ... 展开更多
关键词 HpaGXoo BIOINFORMATICS structure analysis Function prediction
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Analysis on Apple Tree Structures by Free Spindle Pruning Mode
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作者 郝婕 索相敏 +3 位作者 李学营 王献革 鄢新民 冯建忠 《Agricultural Science & Technology》 CAS 2016年第10期2238-2241,共4页
To determine the correlation between the stem taperingness and central shaft by free spindle pruning mode on different apple cultivars, the central shaft growth data of three cultivars of free spindle short shoot "F... To determine the correlation between the stem taperingness and central shaft by free spindle pruning mode on different apple cultivars, the central shaft growth data of three cultivars of free spindle short shoot "Fuji", free spindle long shoot "Fuji", free spindle "Huaguan" were investigated in Xingtang County of Hebei Province by SPSS analysis. The results showed that the stem taperingness on free spindle short shoot "Fuji" was in negative correlation with central shaft, but the correlation was not significant. While the stem taperingness on free spindle long shoot "Fuji" was in positive correlation with central shaft, but the correlation was not significant either. The stern taperingness on free spindle "Huaguan" was in negative correlation with central shaft, and the correlation between the stem taperingness and the central shaft total length was significant at the level of 0.01. The results.provided scientific theoretical basis for guiding the dwarfing rootstocks close planting apple tree pruning technology. 展开更多
关键词 APPLE Free spindle pruning mode structure analysis
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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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Genetic diversity and population structure analysis of 161 broccoli cultivars based on SNP markers 被引量:4
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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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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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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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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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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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Contrastive analysis and crashworthiness optimization of two composite thin-walled structures 被引量:4
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作者 谢素超 周辉 +1 位作者 梁习锋 任鑫 《Journal of Central South University》 SCIE EI CAS 2014年第11期4386-4394,共9页
For the safety protection of passengers when train crashes occur, special structures are crucially needed as a kind of indispensable energy absorbing device. With the help of the structures, crash kinetic-energy can b... For the safety protection of passengers when train crashes occur, special structures are crucially needed as a kind of indispensable energy absorbing device. With the help of the structures, crash kinetic-energy can be completely absorbed or dissipated for the aim of safety. Two composite structures(circumscribed circle structure and inscribed circle structure) were constructed. In addition, comparison and optimization of the crashworthy characteristic of the two structures were carried out based on the method of explicit finite element analysis(FEA) and Kriging surrogate model. According to the result of Kriging surrogate model, conclusions can be safely drawn that the specific energy absorption(SEA) and ratio of specific energy absorption to initial peak force(REAF) of circumscribed circle structure are lager than those of inscribed circle structure under the same design parameters. In other words, circumscribed circle structure has better performances with higher energy-absorbing ability and lower initial peak force. Besides, error analysis was adopted and the result of which indicates that the Kriging surrogate model has high nonlinear fitting precision. What is more, the SEA and REAF optimum values of the two structures have been obtained through analysis, and the crushing results have been illustrated when the two structures reach optimum SEA and REAF. 展开更多
关键词 contrastive analysis crashworthiness optimization composite structure Kriging surrogate model finite element analysis
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Seismic design and analysis of nuclear power plant structures 被引量:2
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作者 Pentti Varpasuo 《Engineering Sciences》 EI 2013年第3期10-19,共10页
The seismic design and analysis of nuclear power plant (NPP) begin with the seismic hazard assessment and design ground motion development for the site. The following steps are needed for the seismic hazard assessment... The seismic design and analysis of nuclear power plant (NPP) begin with the seismic hazard assessment and design ground motion development for the site. The following steps are needed for the seismic hazard assessment and design ground motion development:a. the development of regional seismo-tectonic model with seismic source areas within 500 km radius centered to the site;b. the development of strong motion prediction equations; c. logic three development for taking into account uncertainties and seismic hazard quantification;d. the development of uniform hazard response spectra for ground motion at the site;e. simulation of acceleration time histories compatible with uniform hazard response spectra. The following phase two in seismic design of NPP structures is the analysis of structural response for the design ground motion. This second phase of the process consists of the following steps:a. development of structural models of the plant buildings;b. development of the soil model underneath the plant buildings for soilstructure interaction response analysis;c. determination of instructure response spectra for the plant buildings for the equipment response analysis. In the third phase of the seismic design and analysis the equipment is analyzed on the basis of in-structure response spectra. For this purpose the structural models of the mechanical components and piping in the plant are set up. In large 3D-structural models used today the heaviest equipment of the primary coolant circuit is included in the structural model of the reactor building. In the fourth phase the electrical equipment and automation and control equipment are seismically qualified with the aid of the in-structure spectra developed in the phase two using large three-axial shaking tables. For this purpose the smoothed envelope spectra for calculated in-structure spectra are constructed and acceleration time is fitted to these smoothed envelope spectra. 展开更多
关键词 seismic hazard assessment design ground motion development analysis of structural response
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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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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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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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Finite element analysis of dynamic response and structure borne noise of gearbox 被引量:4
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作者 LIU Wen LIN Teng-jiao LI Run-fang DU Xue-song 《Journal of Chongqing University》 CAS 2007年第2期119-124,共6页
A dynamic finite element method combined with finite element mixed formula for contact problem is used to analyze the dynamic characteristics of gear system. Considering the stiffness excitation, error excitation and ... A dynamic finite element method combined with finite element mixed formula for contact problem is used to analyze the dynamic characteristics of gear system. Considering the stiffness excitation, error excitation and meshing shock excitation, the dynamic finite element model is established for the entire gear system which includes gears, shafts, bearings and gearbox housing. By the software of I-DEAS, the natural frequency, normal mode, dynamic time-domain response, frequency-domain response and one-third octave velocity grade structure borne noise of gear system are studied by the method of theoretical modal analysis and dynamic response analysis. The maximum values of vibration and structure borne noise are occurred at the mesh frequency of output grade gearing. 展开更多
关键词 aear system finite element method: modal analysis response analyses structure borne noise
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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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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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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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