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A Simplified Method for the Stress Analysis of Underground Transfer Structures Crossing Multiple Subway Tunnels
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作者 Shen Yan Dajiang Geng +2 位作者 Ning Dai Mingjian Long Zhicheng Bai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2893-2915,共23页
According to the design specifications,the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock layer.To address this challenge,a subterranean transfer str... According to the design specifications,the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock layer.To address this challenge,a subterranean transfer structure spanning multiple subway tunnels was proposed.Deliberating on the function of piles in the transfer structure as springs with axial and bending stiffness,and taking into account the force balance and deformation coordination conditions of beams and plates within the transfer structure,we established a simplified mechanical model that incorporates soil stratification by combining it with the Winkler elastic foundation beam model.The resolved established simplifiedmechanicalmodel employed finite difference technology and the Newton-Simpsonmethod,elucidating the mechanical mechanism of the transfer structure.The research findings suggest that the load carried by the upper structural columns can be transferred to the pile foundation beneath the beams through the transfer structure,subsequently reaching the deep soil layer and ensuring minimal impact on adjacent tunnels.The established simplified analysis method can be used for stress analysis of the transfer structure,concurrently considering soil stratification,pile foundation behavior,and plate action.The pile length,pile section size,and beam section size within the transfer structure should account for the characteristics of the upper load,ensuring an even distribution of the beam bending moment. 展开更多
关键词 Crossing tunnels transfer structure force mechanism simplify analysis layered soil mass
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Static and Thermal Analysis of Aluminium (413,390,384 and 332) Piston Using Finite Element Method
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作者 Offei David Inusah Jacob Kwaku Nkrumah Vincent Akolbire Atindana 《Modeling and Numerical Simulation of Material Science》 2024年第1期1-38,共38页
The main objective of this research was to examine the suitability of aluminium alloy to design a piston of an internal combustion engine for improvement in weight and cost reduction. The piston was modelled using Aut... The main objective of this research was to examine the suitability of aluminium alloy to design a piston of an internal combustion engine for improvement in weight and cost reduction. The piston was modelled using Autodesk Inventor 2017 software. The modelled piston was then imported into Ansys for further analysis. Static structural and thermal analysis were carried out on the pistons of the four different materials namely: Al 413 alloy, Al 384 alloy, Al 390 alloy and Al332 alloy to determine the total deformation, equivalent Von Mises stress, maximum shear stress, and the safety factor. The results of the study revealed that, aluminium 332 alloy piston deformed less compared to the deformations of aluminium 390 alloy piston, aluminium 384 alloy piston and aluminium 413 alloy piston. The induced Von Mises stresses in the pistons of the four different materials were found to be far lower than the yield strengths of all the materials. Hence, all the selected materials including the implementing material have equal properties to withstand the maximum gas load. All the selected materials were observed to have high thermal conductivity enough to be able to withstand the operating temperature in the engine cylinders. 展开更多
关键词 Von Mise stress total deformation Aluminium alloy thermal analysis. PIStoN Static structural Heat fux
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Analysis of Urban Agglomeration Network Structure Based on Baidu Migration Data: A Case Study of the Guangdong-Hong Kong-Macao Greater Bay Urban Agglomeration
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作者 XIA Yuan WANG Bin 《Journal of Landscape Research》 2024年第4期47-50,共4页
The inter-city linkage heat data provided by Baidu Migration is employed as a characterization of inter-city linkages in order to facilitate the study of the network linkage characteristics and hierarchical structure ... The inter-city linkage heat data provided by Baidu Migration is employed as a characterization of inter-city linkages in order to facilitate the study of the network linkage characteristics and hierarchical structure of urban agglomeration in the Greater Bay Area through the use of social network analysis method.This is the inaugural application of big data based on location services in the study of urban agglomeration network structure,which represents a novel research perspective on this topic.The study reveals that the density of network linkages in the Greater Bay Area urban agglomeration has reached 100%,indicating a mature network-like spatial structure.This structure has given rise to three distinct communities:Shenzhen-Dongguan-Huizhou,Guangzhou-Foshan-Zhaoqing,and Zhuhai-Zhongshan-Jiangmen.Additionally,cities within the Greater Bay Area urban agglomeration play different roles,suggesting that varying development strategies may be necessary to achieve staggered development.The study demonstrates that large datasets represented by LBS can offer novel insights and methodologies for the examination of urban agglomeration network structures,contingent on the appropriate mining and processing of the data. 展开更多
关键词 Baidu migration data Social network analysis Urban agglomeration network structure Greater Bay Area urban agglomeration
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Nonlinear Time History Analysis for the Different Column Orientations under Seismic Wave Synthetic Approach
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作者 Mo Shi Peng Wang +1 位作者 Xiaoyan Xu Yeol Choi 《World Journal of Engineering and Technology》 2024年第3期587-616,共30页
The significant impact of earthquakes on human lives and the built environment underscores the extensive human and economic losses caused by structural collapses. Over the years, researchers have focused on improving ... The significant impact of earthquakes on human lives and the built environment underscores the extensive human and economic losses caused by structural collapses. Over the years, researchers have focused on improving seismic design to mitigate earthquake-induced damages and enhance structural performance. In this study, a specific reinforced concrete (RC) frame structure at Kyungpook National University, designed for educational purposes, is analyzed as a representative case. Utilizing SAP 2000, the research conducts a nonlinear time history analysis to assess the structural performance under seismic conditions. The primary objective is to evaluate the influence of different column section designs, while maintaining identical column section areas, on structural behavior. The study employs two distinct seismic waves from Abeno (ABN) and Takatori (TKT) for the analysis, comparing the structural performance under varying seismic conditions. Key aspects examined include displacement, base shear force, base moment, joint radians, and layer displacement angle. This research is anticipated to serve as a valuable reference for seismic restraint reinforcement work on RC buildings, enriching the methods used for evaluating structures through nonlinear time history analysis based on the synthetic seismic wave approach. 展开更多
关键词 Nonlinear Time History analysis Nonlinear Dynamic analysis Seismic Wave Synthetic Seismic Restraint RC Frame structure Column Orientation
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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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THE SATELLITE STRUCTURE TOPOLOGY OPTIMIZATION BASED ON HOMOGENIZATION METHOD AND ITS SIZE SENSITIVITY ANALYSIS 被引量:2
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作者 ChenChangya PanJin WangDeyu 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第2期173-180,共8页
With the development of satellite structure technology, more and more design parameters will affect its structural performance. It is desirable to obtain an optimal structure design with a minimum weight, including op... With the development of satellite structure technology, more and more design parameters will affect its structural performance. It is desirable to obtain an optimal structure design with a minimum weight, including optimal configuration and sizes. The present paper aims to describe an optimization analysis for a satellite structure, including topology optimization and size optimization. Based on the homogenization method, the topology optimization is carried out for the main supporting frame of service module under given constraints and load conditions, and then the sensitivity analysis is made of 15 structural size parameters of the whole satellite and the optimal sizes are obtained. The numerical result shows that the present optimization design method is very effective. 展开更多
关键词 satellite structure topology optimization homogenization method size optimization sensitivity analysis
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Analysis of the Spatial Structure of Tourism Resources in Ji'an City 被引量:2
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作者 ZHU Jian SONG Juan 《Journal of Landscape Research》 2013年第Z3期35-38,共4页
This paper analyzed characteristics of tourism resources in Ji'an City,and carried out quantitative analysis of local tourism resources based on agglomeration effect of resources,connectivity analysis,and accessib... This paper analyzed characteristics of tourism resources in Ji'an City,and carried out quantitative analysis of local tourism resources based on agglomeration effect of resources,connectivity analysis,and accessibility analysis. The results showed that the city has poor loop of tourism network,major scenic areas(spots) have moderate network accessibility,in view of this,suggestions for the optimum development of local tourism industry were proposed. 展开更多
关键词 Ji’an CITY toURISM resources Spatial structure AGGLOMERATION effect CONNECTIVITY analysis ACCESSIBILITY analysis
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STRUCTURE FEATURES AND COMPOSITE ANALYSIS OF CONVECTIVE CELLS IN A WARM SECTOR HEAVY RAINFALL EVENT OVER SOUTHERN CHINA 被引量:1
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作者 QIAN Lei DING Zhi-ying +1 位作者 ZHAO Xiang-jun XIA Fan 《Journal of Tropical Meteorology》 SCIE 2017年第3期245-258,共14页
This paper uses the ARW-WRF model to carry out a numerical simulation of a warm-sector heavy rainfall event over southern China on the 22-23 May, 2014. A composite analysis method was used to analyze the evolution pro... This paper uses the ARW-WRF model to carry out a numerical simulation of a warm-sector heavy rainfall event over southern China on the 22-23 May, 2014. A composite analysis method was used to analyze the evolution process and structural features of the convective cells on a convection line during this rainfall event. This analysis identified three stages:(1) Stage of activation: the equivalent potential temperature surfaces as lower layers start to bulge and form warm cells and weak vertical convective cloud towers which are subject to the impact of low-level warm moist updrafts in the rainfall sector;(2) Stage of development: the warm cells continue to bulge and form warm air columns and the convective cloud towers develop upwards becoming stronger as they rise;(3) Stage of maturity: the warm air columns start to connect with the stable layer in the upper air; the convective cloud tower will bend and tilt westward with each increasing in height, and the convection cell is characterized by a "crescent-shaped echo" above the 700 h Pa plane. During this stage the internal temperature of the cell is higher than the ambient temperature and the dynamic structural field is manifested as intensive vertical upward movement. The large-value centers of the northerly and westerly winds in the middle layer correspond to the warm moist center in the cells and the relatively cold center south of the warm air column. Further analysis shows that the formation of the "crescent-shaped" convective cell is associated with horizontal vorticity. Horizontal vorticity in the center and west of the warm cell experiences stronger cyclonic and anticyclonic shear transformation over time; this not only causes the original suborbicular cell echo shape to develop into a crescent-like shape, but also makes a convection line consisting of cells that develop to the northwest. 展开更多
关键词 convective cells structural features horizontal vorticity composite analysis
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DIGITAL IMAGE ANALYSIS OF PHASE STRUCTURE IN THE BLEND OF POLY(BUTYLENE TEREPHTHALATE-COCAPROLACTONE) WITH POLYCARBONATE
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作者 马德柱 贺丽玲 +3 位作者 邹应芳 罗筱烈 Takafumi Hayashi Toshio Nishi 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第1期44-48,共5页
The digital image processing technique was used for the extraction of physical information from the temporal image of phase structure in the process of phase separation in the blend of poly (butylene terephthalate-co-... The digital image processing technique was used for the extraction of physical information from the temporal image of phase structure in the process of phase separation in the blend of poly (butylene terephthalate-co-caprolactone )with polycarbonate. The power spectrum images of the two-dimensional Fourier transformation (2DFT) of the temporal image of phase structure reflect the change of the phase size with time. 展开更多
关键词 Digital image analysis Phase structure Fourier transformation Wave vector BCL copolymer
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Factor Decomposition and Regression Analysis of the Energy Related Carbon Emissions in Shandong, China: A Perspective of Industrial Structure
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作者 Weifeng Gong Baoqing Zhu +3 位作者 Chuanhui Wang Zhenyue Fan Mengzhen Zhao Liang Chen 《Energy Engineering》 EI 2021年第4期981-994,共14页
An in-depth study of the energy related carbon emissions has important practical significance for carbon emissions reduction and structural adjustment in Shandong Province and throughout China.Based on the perspective... An in-depth study of the energy related carbon emissions has important practical significance for carbon emissions reduction and structural adjustment in Shandong Province and throughout China.Based on the perspective of industrial structure,the expanded KAYA equation to measure the energy related carbon emissions of the primary industries(Resources and Agriculture)and secondary industries(Manufacturing and Construction)and tertiary industries(Retail and Service)was utilized in Shandong Province from 2011 to 2017.The carbon emissions among industries in Shandong Province were empirically analyzed using the Logarithmic Mean Divisia Index decomposition approach.The results were follows:(1)Under the three industrial dimensions,the energy structure effect and the energy intensity effect have a restraining influence on the carbon emissions of the three industries.(2)The development level effect and the employment scale effect play a pulling role in carbon emissions.(3)From the perspective of the employment structure effect of the primary industry,there is a restraining effect on carbon emissions,while the employment structure effects of the secondary and tertiary industries play a pulling role in carbon emissions,and the employment structure effect of the tertiary industry has a greater pulling effect on carbon emissions than the secondary industry. 展开更多
关键词 Carbon emissions industrial structure expanded KAYA equation LMDI decomposition regression analysis
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3D characterization and analysis of pore structure of packed ore particle beds based on computed tomography images 被引量:12
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作者 杨保华 吴爱祥 +1 位作者 缪秀秀 刘金枝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期833-838,共6页
Methods and procedures of three-dimensional (3D) characterization of the pore structure features in the packed ore particle bed are focused. X-ray computed tomography was applied to deriving the cross-sectional imag... Methods and procedures of three-dimensional (3D) characterization of the pore structure features in the packed ore particle bed are focused. X-ray computed tomography was applied to deriving the cross-sectional images of specimens with single particle size of 1-2, 2-3, 3-4, 4-5, 5-6, 6-7, 7-8, 8-9, 9-10 ram. Based on the in-house developed 3D image analysis programs using Matlab, the volume porosity, pore size distribution and degree of connectivity were calculated and analyzed in detail. The results indicate that the volume porosity, the mean diameter of pores and the effective pore size (d50) increase with the increasing of particle size. Lognormal distribution or Gauss distribution is mostly suitable to model the pore size distribution. The degree of connectivity investigated on the basis of cluster-labeling algorithm also increases with increasing the particle size approximately. 展开更多
关键词 packed ore particle bed 3D pore structure X-ray computed tomography image analysis
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Characteristic Analysis of the Village and Town Structure——A Case of Jinhu County in Jiangsu Province,China 被引量:1
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作者 LUO Ya-li,ZHANG Chang-xin Huaiyin Institute of Technology,Huai’an 223001,China 《Asian Agricultural Research》 2010年第5期45-48,52,共5页
This thesis gives overview of the connotation of rural spatial structure,indicating 4 kinds of elements,namely nodus,passage,region and flow.Their spatial arrangement and interaction lead to the corresponding rural sp... This thesis gives overview of the connotation of rural spatial structure,indicating 4 kinds of elements,namely nodus,passage,region and flow.Their spatial arrangement and interaction lead to the corresponding rural spatial structure.This thesis also offers panorama of the related theoretical progress of intra-county and rural areas,indicating that the research theories of regional spatial structure at present,mainly focus on macroscopic region or urban space,but there is shortage of researches on county spatial structure,especially microscopic rural spatial structure.On such basis,4 kinds of theoretical models and characteristics of regional spatial structure have been introduced.We build analysis index system of rural structural elements on the basis of 4 elements,and conduct rural spatial structural analysis,taking Jinhu County as an example.The result shows that rural spatial structure in Jinhu County is still at stage of nucleus-cluster development and rural system is not so sound.In addition,the passage network system of infrastructure has not taken shape,and county economy presents diseconomy of scale.The spatial interaction and association among towns in Jinhu County are weak.The characteristic analysis model of spatial structure in this research can objectively reflect regional characteristic of spatial structure. 展开更多
关键词 the VILLAGE and toWN spatial structure Characteris
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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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Computational analysis of genetic loci required for amphid structure and functions and their possibly corresponding microRNAs in C. elegans 被引量:1
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作者 胡亚欧 孙阳 +1 位作者 叶波平 王大勇 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第1期9-20,共12页
Objective To examine the important roles of microRNAs (miRNAs) in regulating amphid structure and function, we performed a computational analysis for the genetic loci required for the sensory perception and their po... Objective To examine the important roles of microRNAs (miRNAs) in regulating amphid structure and function, we performed a computational analysis for the genetic loci required for the sensory perception and their possibly corresponding miRNAs in C. elegans. Methods Total 55 genetic loci required for the amphid structure and function were selected. Sequence alignment was combined with E value evaluation to investigate and identify the possible corresponding miRNAs. Results Total 30 genes among the 55 genetic loci selected have their possible corresponding regulatory miRNA(s), and identified genes participate in the regulation of almost all aspects of amphid structure and function. In addition, our data suggest that both the amphid structure and the amphid functions might be regulated by a series of network signaling pathways. Moreover, the distribution of miRNAs along the 3' untranslated region (UTR) of these 30 genes exhibits different patterns. Conclusion We present the possible miRNA-mediated signaling pathways involved in the regulation of chemosensation and thermosensation by controlling the corresponding sensory neuron and interneuron functions. Our work will be useful for better understanding of the miRNA-mediated control of the chemotaxis and thermotaxis in C. elegans. 展开更多
关键词 microRNA cilia structure sensory neuron INTERNEURON computational analysis C. elegans
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Analysis on Fuji Apple Tree Structures and Related Factors under Different Pruning Modes 被引量:1
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作者 郝婕 索相敏 +4 位作者 李学营 魏亮 王献革 鄢新民 冯建忠 《Agricultural Science & Technology》 CAS 2017年第12期2528-2531,2535,共5页
To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and sl... To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and slenderspindle short shoot in Xingtang County of Hebai Province were investigated, then by SPSS anal- ysis, the correlations between the taperingness and each growth factor of inserted small branch were compared. The results showed that the taperingness of central trunk of free spindle dwarf-shoot Fuji apple treeshad negative correlations with each factor of inserted small branch, while the taperingness of central trunk of free spin- dle long-shoot Fuji apple treeshad positive correlations with each factor of inserted small branch, the taperingness of central trunk of slenderspindle short-shootFuji ap- ple treeshad negative correlation with total thickness of inserted small branch, but had positive correlations with other factors. This study can provide a scientifictheo- retical basis for the pruning technology of high-density planting trees grafting by dwarfing self-rooted rootstock. 展开更多
关键词 PRUNING Fuji apple Tree structures analysis of related factors
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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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Research on the Agriculture Production Structure in Shandong Province Based on the Grey Relational Dynamic Analysis 被引量:1
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作者 侯修升 张娥娥 《Agricultural Science & Technology》 CAS 2016年第7期1753-1756,共4页
In accordance with grey relational dynamic analysis, overall structure and inner structure of agriculture were analyzed and the grey relational sequence inte- grals were concluded of Shandong agriculture during 2003-2... In accordance with grey relational dynamic analysis, overall structure and inner structure of agriculture were analyzed and the grey relational sequence inte- grals were concluded of Shandong agriculture during 2003-2014. Besides, the re- search analyzed the contributions by specific agricultural sectors and Shandong a- gricultural structure from natural endowments, policy, and agricultural modernization. Finally, the development countermeasures and suggestions were proposed. 展开更多
关键词 Grey dynamic analysis Agricultural industry structure OPTIMIZATION
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Mapping theme trends and knowledge structures for human neural stem cells:a quantitative and co-word biclustering analysis for the 2013-2018 period 被引量:5
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作者 Wen-Juan Wei Bei Shi +3 位作者 Xin Guan Jing-Yun Ma Ya-Chen Wang Jing Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第10期1823-1832,共10页
Neural stem cells,which are capable of multi-potential differentiation and self-renewal,have recently been shown to have clinical potential for repairing central nervous system tissue damage.However,the theme trends a... Neural stem cells,which are capable of multi-potential differentiation and self-renewal,have recently been shown to have clinical potential for repairing central nervous system tissue damage.However,the theme trends and knowledge structures for human neural stem cells have not yet been studied bibliometrically.In this study,we retrieved 2742 articles from the PubMed database from 2013 to 2018 using "Neural Stem Cells" as the retrieval word.Co-word analysis was conducted to statistically quantify the characteristics and popular themes of human neural stem cell-related studies.Bibliographic data matrices were generated with the Bibliographic Item Co-Occurrence Matrix Builder.We identified 78 high-frequency Medical Subject Heading(MeSH)terms.A visual matrix was built with the repeated bisection method in gCLUTO software.A social network analysis network was generated with Ucinet 6.0 software and GraphPad Prism 5 software.The analyses demonstrated that in the 6-year period,hot topics were clustered into five categories.As suggested by the constructed strategic diagram,studies related to cytology and physiology were well-developed,whereas those related to neural stem cell applications,tissue engineering,metabolism and cell signaling,and neural stem cell pathology and virology remained immature.Neural stem cell therapy for stroke and Parkinson’s disease,the genetics of microRNAs and brain neoplasms,as well as neuroprotective agents,Zika virus,Notch receptor,neural crest and embryonic stem cells were identified as emerging hot spots.These undeveloped themes and popular topics are potential points of focus for new studies on human neural stem cells. 展开更多
关键词 nerve REGENERATION human NEURAL stem cells PubMed bibliometric analysis biclustering analysis co-word analysis strategic diagram analysis social network analysis hot research topics mapping theME TRENDS knowledge structures NEURAL REGENERATION
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Vector-intensity measure based seismic vulnerability analysis of bridge structures 被引量:8
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作者 Li Zhongxian Li Yang Li Ning 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第4期695-705,共11页
This paper presents a method for seismic vulnerability analysis of bridge structures based on vector-valued intensity measure (viM), which predicts the limit-state capacities efficiently with multi-intensity measure... This paper presents a method for seismic vulnerability analysis of bridge structures based on vector-valued intensity measure (viM), which predicts the limit-state capacities efficiently with multi-intensity measures of seismic event. Accounting for the uncertainties of the bridge model, ten single-bent overpass bridge structures are taken as samples statistically using Latin hypercube sampling approach. 200 earthquake records are chosen randomly for the uncertainties of ground motions according to the site condition of the bridges. The uncertainties of structural capacity and seismic demand are evaluated with the ratios of demand to capacity in different damage state. By comparing the relative importance of different intensity measures, Sa(T1) and Sa(T2) are chosen as viM. Then, the vector-valued fragility functions of different bridge components are developed. Finally, the system-level vulnerability of the bridge based on viM is studied with Duunett- Sobel class correlation matrix which can consider the correlation effects of different bridge components. The study indicates that an increment IMs from a scalar IM to viM results in a significant reduction in the dispersion of fragility functions and in the uncertainties in evaluating earthquake risk. The feasibility and validity of the proposed vulnerability analysis method is validated and the bridge is more vulnerable than any components. 展开更多
关键词 bridge structure seismic vulnerability analysis vector-valued intensity measure components' correlation system vulnerability
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