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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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Genetic Diversity and Population Structure Analysis of Barley Landraces from Shanghai Region Using Genotyping-by-Sequencing
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作者 Luli Li Nigel G.Halford +5 位作者 Huihui Wang Yingjie Zong Zhenzhu Guo Ruiju Lu Chenghong Liu Zhiwei Chen 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第4期1275-1287,共13页
Barley(Hordeum vulgare L.)is an important economic crop for food,feed and industrial raw materials.In the present research,112 barley landraces from the Shanghai region were genotyped using genotyping-by-sequencing(GB... Barley(Hordeum vulgare L.)is an important economic crop for food,feed and industrial raw materials.In the present research,112 barley landraces from the Shanghai region were genotyped using genotyping-by-sequencing(GBS),and the genetic diversity and population structure were analyzed.The results showed that 210,268 Single Nucleotide Polymorphisms(SNPs)were present in total,and the average poly-morphism information content(PIC)was 0.1642.Genetic diversity and population structure analyses suggested that these barley landraces were differentiated and could be divided into three sub-groups,with morphological traits of row-type and adherence of the hulls the main distinguishing factors between groups.Genotypes with similar or duplicated names were also investigated according to their genetic backgrounds and seed appearances.This study provided valuable information on barley landraces from the Shanghai region,and showed that all these barley landraces should be protected and used for future breeding programs. 展开更多
关键词 Hordeum vulgare L cluster analysis population structure SNP markers
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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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Structure variety and its effects on biological activity of tea polysaccharides 被引量:3
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作者 Ting Hu Peng Wu +5 位作者 Jianfeng Zhan Weixin Wang Junfeng Shen Meiyan Wang Chi-Tang Ho Shiming Li 《Food Science and Human Wellness》 SCIE 2022年第3期587-597,共11页
Tea polysaccharides(TPSs),one of the major bioactive ingredients in tea,have been widely studied due to their variety of biological activities,including antioxidant,cancer prevention,hypoglycemia,anti-fatigue,anti-coa... Tea polysaccharides(TPSs),one of the major bioactive ingredients in tea,have been widely studied due to their variety of biological activities,including antioxidant,cancer prevention,hypoglycemia,anti-fatigue,anti-coagulant,anti-obesity and immunomodulatory effect.The biological effectiveness of TPSs has direct relation with their structures such as monosaccharide composition,molecular weight,glycosidic linkages,conformation and others,which can be influenced by tea materials,processing methods,extraction and purification procedures among others.Comparing to the study of tea polyphenols,the exploration of TPSs in structural elucidation and biofunctionality is very preliminary.Yet several factors affecting the structural change of TPSs have been studied and identified.Consequently,the variation of some TPS biological activity brought by the change of TPS structures has been evaluated and preliminary correlation of structure activity relationship of TPSs has been performed.Therefore,this review aims to serve as a summary research report regarding the influencing factors on TPSs structures and consequential effects on the biological activities of TPSs.We hope to provide updated information and systematic references for future study and functional food development of TPSs. 展开更多
关键词 Tea polysaccharides structure variety BIOACTIVITIES RELATIONSHIP Influencing factors
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Effects of Yupingfeng Polysaccharides on the Spleen Tissue Structure of Acute and Chronic Immunocompromised Mice 被引量:1
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作者 Hua DENG Hong YANG 《Medicinal Plant》 CAS 2018年第5期93-96,共4页
[Objectives] To study the protective and recovery effects of Yupingfeng polysaccharides( YPF-P) on spleen tissue structure of acute and chronic immunocompromised mice. [Methods]First,90 mice in the protective group we... [Objectives] To study the protective and recovery effects of Yupingfeng polysaccharides( YPF-P) on spleen tissue structure of acute and chronic immunocompromised mice. [Methods]First,90 mice in the protective group were injected with cyclophosphamide to replicate the chronic immunosuppressive model,and observe the protective effects of different doses of YPF-P on the spleen; 120 mice in the recovery group were injected with cyclophosphamide continuously to replicate the acute immune injury model,to observe the effects of YPF-P on spleen recovery. Besides,YPF-P positive control group was established to observe its effects on the spleen structure and function of normal mice. Testing indicators include spleen morphology and tissue structure,body mass,and spleen index. [Results]In the protective group and the recovery group,the spleen volume of the mice with different YPF-P doses increased significantly,and lymphocytes proliferated,showing obvious structural compensation and repair,and showing a dose-effect relationship. In the positive control group,the spleen function of the normal mice was significantly enhanced,and the spleen lymphoid tissue showed significant orderly proliferation. [Conclusions]Yupingfeng polysaccharides can effectively protect the function and structure of spleen,improve acute and chronic immune damage induced by cyclophosphamide,greatly promote the recovery of spleen structure and function after immune injury,and also can significant enhance the spleen structure and function of normal mice. 展开更多
关键词 YUPINGFENG polysaccharides Low immunity SPLEEN Tissue structure MICE
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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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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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Genetic diversity and population structure analysis of 161 broccoli cultivars based on SNP markers 被引量:1
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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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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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Influence of X-ray Powder Diffraction Instrument Error on Crystalline Structure Analysis
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作者 HUANGQing-Ming YUJian-Chang WANGYun-Min WUWan-Guo 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第6期691-695,共5页
Standard mica was used to correct the X-ray powder diffraction instrument error and mathematic methods were employed to find the correction equation. By analyzing mullite sample and comparing the corrected and uncorre... Standard mica was used to correct the X-ray powder diffraction instrument error and mathematic methods were employed to find the correction equation. By analyzing mullite sample and comparing the corrected and uncorrected analysis results we found the former is obviously more reasonable. So the conclusion is that the X-ray powder diffraction instrument error greatly affects the crystalline structure analysis, and the above method is convenient and effective for the correction of instrument error. 展开更多
关键词 instrument error structure analysis polycrystalline diffraction
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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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Structure Analysis of Beta-alumina Synthesized by Solid State Reaction
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作者 吉光辉 朱承飞 常凤真 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第8期1227-1233,共7页
The crystal structure of a solid electrolyte, beta-A12O3, was investigated by XRD analysis and demonstrated by Diamond software. Its chemical formula was verified by the Ag ion molten salt exchange method and X-ray fl... The crystal structure of a solid electrolyte, beta-A12O3, was investigated by XRD analysis and demonstrated by Diamond software. Its chemical formula was verified by the Ag ion molten salt exchange method and X-ray fluorescence analysis (XRF). The chemical formula of β- A12O3 is Na2O·8.52A12O3, and its crystal is of hexagonal, space group P63/mmc, with a = 5.5941 A and c = 22.5300 A. The chemical formula of β-Al20 is Na2O·6.03A12O3, and its crystal is of trigonal, space group R3m, with a = 5.6017 A and c = 33.6219 A. The maximum span in the sodion migration of β-phase (2.4283 A) is only about a third of that for the β-phase (6.9037 A), so the β-phase has higher ionic conductivity than the r-phase. 展开更多
关键词 beta-Al2O3 structure analysis solid state reaction
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Local Structure Analysis of Lead Zinc Niobate-Barium Titanate Ceramic by X-Ray Absorption Spectroscopy and Density Functional Calculation
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作者 Kanokwan Kanchiang Phakkhananan Pakawanit Rattikorn Yimnirun 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第8期113-116,共4页
The local structure of an alternative Pb(Zn1/3Nb2/3)O3-based perovskite ceramic is investigated. The 0.07BaTiO33-0.93Pb(Zn1/3Nb2/3)O3 ceramic is synthesized using a combination of Zn3Nb2O8 B-site precursor and BaT... The local structure of an alternative Pb(Zn1/3Nb2/3)O3-based perovskite ceramic is investigated. The 0.07BaTiO33-0.93Pb(Zn1/3Nb2/3)O3 ceramic is synthesized using a combination of Zn3Nb2O8 B-site precursor and BaTiO33 perovskite phase stabilizer. Then, x-ray absorption spectroscopy and density functional theory are employed to calculate the local structure configuration and formation energy of the prepared samples. Ba2+ is found to replace Pb2+ in AA-site with Zn2+ occupying BB-site in Pb(Zn1/3Nb2/3)O3, while in the neighboring structure, Ti4+4+ replaces Nb5+5+ in BB-site with Pb2+2+ occupying AA-site. With the substitution of BaTiO33 in Pb(Zn1/3Nb2/3)O3, the bond length between Zn2+ and Pb2+ is longer than that of the typical perovskite phase of Pb(Zn1/3Nb2/3)O3. This indicates the key role of BaTiO33 in decreasing the steric hindrance of Pb2+ lone pair, and the mutual interactions between Pb2+ lone pair and Zn2+ and the formation energy is seen to decrease. This finding of the formation energy and local structure configuration relationship can further extend a fundamental understanding of the role of BaTiO33 in stabilizing the perovskite phase in PbZn13Nb23O3-based materials, which in turn will lead to an improved preparation technique for desired electrical properties. 展开更多
关键词 PB Local structure analysis of Lead Zinc Niobate-Barium Titanate Ceramic by X-Ray Absorption Spectroscopy and Density Functional Calculation EXAFS BA XANES Zn
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Structure Analysis for Hydrate Models of Ethyleneimine Oligomer by Quantum Chemical Calculation 被引量:1
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作者 Minoru Kobayashi Hisaya Sato 《Pharmacology & Pharmacy》 2010年第2期60-68,共9页
Structure analyses for hydrate models of ethyleneimine oligomer (5-mer as model of PEI) were investigated by quantum chemical calculations. Conformation energies and structures optimized for hydrate models of (ttt)5 a... Structure analyses for hydrate models of ethyleneimine oligomer (5-mer as model of PEI) were investigated by quantum chemical calculations. Conformation energies and structures optimized for hydrate models of (ttt)5 and (tgt)5 conformers were examined. Hydrate ratio, h [h = H2O/N (mol)], was set from 0.5 to 2. In anhydrates, (tg+t)5 conformer was more stable (?1.8 kcal/m.u.) than (ttt)5. In hydrates, (ttt)5 conformers were more stable (?0.7 - ?4.3) than (tg+t)5. These results corresponded to experimental results that anhydrous linear PEI crystal changes from double helical to single planar chain in hydration process. Structures calculated for (ttt)5 agreed in those observed for hydrates of PEI. In all (tg+t)5 conformers, O???H bonds between waters were found with the decreases of N???H bonds between imino group and water. The O???H bonds in (tg+t)5 conformer resulted in its high chain torsion, and strongly related with instability and structure change (large swelling). 展开更多
关键词 structure analysis CONFORMATION HYDRATE Poly(Ethyleneimine) OLIGOMER QUANTUM Chemical Calcu-lation
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GAP STRUCTURE ANALYSIS OF FOREST TRANSECT USINGTHE 1-D DISCRETE WAVELET TRANSFORM
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作者 何伟国 祖元刚 +2 位作者 朱虹 陈力 孙娟 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1996年第3期40-43,共4页
Wavelets is a very effective technique for time-frequency analysis with the ability of preserving loeal information, applied to many areas such as nonlinear science, information processing.quantum physics etc.. In thi... Wavelets is a very effective technique for time-frequency analysis with the ability of preserving loeal information, applied to many areas such as nonlinear science, information processing.quantum physics etc.. In this paper. from the view of ecology spatial pattern, the authors try to process the sample data of Larix forest transects to identify the canopy gap structures by wavelet analysis. The caleulation of wavelet variance, derived from the transtform facilitates comparison based on dominant scale of pattern between multiple datasets such as the stands described. 展开更多
关键词 WAVELET TRANSFORM Spatial analysis CANOPY gap structure
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FINE STRUCTURE ANALYSIS OF DEFORMED STEEL 1Cr18Ni9
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作者 TENG Feng’en WANG Yuming XU Yue Jilin University,Changchun,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第4期266-268,共3页
X-ray diffraction profiles of various deformed steel 1Cr18Ni9 through stepped scanning were obtained.By profile analysis,some structure parameters such as effective domain size D_(eff), dislocation density in domain,d... X-ray diffraction profiles of various deformed steel 1Cr18Ni9 through stepped scanning were obtained.By profile analysis,some structure parameters such as effective domain size D_(eff), dislocation density in domain,distribution parameterand bulk stored energy densiy (E/V),etc.,were obtained.The results were compared with those of TEM observation.The true domain sizes D_e are comparable,but the minimum and characteristics of width of stack- ing fault are different.This may be resulted from the large fluctuation in width of stacking fault. 展开更多
关键词 austenitic stainless steel fine structure X-ray analysis
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Robot Structure Analysis在山岭高速公路施工中的应用
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作者 赵远华 罗礼华 《建材与装饰》 2019年第20期255-256,共2页
随着BIM理念发展,BIM技术的应用开始从设计走向实践,越来越多的被运用在施工中。BIM也不再是单纯的模型展示,更多被实际运用在计算方面,BIM不仅仅是算量,碰撞检查等,在结构校核方面也开始有了更多的运用。计算机运用在结构分析方面并不... 随着BIM理念发展,BIM技术的应用开始从设计走向实践,越来越多的被运用在施工中。BIM也不再是单纯的模型展示,更多被实际运用在计算方面,BIM不仅仅是算量,碰撞检查等,在结构校核方面也开始有了更多的运用。计算机运用在结构分析方面并不是新的应用,计算机辅助很早就出现在设计中,但在施工中很少涉及。BIM技术的发展带来了改变,现今的结构分析能非常简单的在计算机中实现,Autodesk给用户提供了一个简易的结构分析软件——Robot Structure Analysis。 展开更多
关键词 BIM structure analysis ROBOT
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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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Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells
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作者 Mingzhe Huang Mi Xiao +3 位作者 Liang Gao Mian Zhou Wei Sha Jinhao Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2479-2505,共27页
Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method ba... Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is proposed.This method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell elements.The geometric and analysis models of thin shells are unified by isogeometric analysis(IGA)to avoid geometric approximation error and improve computational accuracy.The topological configurations of thin-shell structures are described by constructing the effective density field on the controlmesh.Local volume constraints are imposed in the proximity of each control point to obtain bone-like cellular structures.To facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global constraint.Several numerical examples are provided to demonstrate the effectiveness of the proposed method.After simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness. 展开更多
关键词 Cellular thin-shell structures isogeometric analysis full-scale topology optimization Kirchhoff–Love shells
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Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments
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作者 He-xiang Wu Jia Qu Lin-zhi Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期312-325,共14页
In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of fragments.Attention is paid to eluc... In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of fragments.Attention is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of fragments.The results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural parameters.In this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances. 展开更多
关键词 Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis
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