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Early Cretaceous Thrust and Nappe Tectonics in North Qilian Shan,Northern Tibetan Plateau:Evidence from Field Mapping,Geochronology,and Deep structural analysis

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Acta Geologica Sinica(English Edition) 2023年第4期97卷 1058-1077页

作者： HAN Lele DING Weicui CHEN Xuanhua SHAO Zhaogang ZHANG Da XIAO Yongjun HE Chengguang WANG Zengzhen LI Bing ZHANG Yiping XU Shenglin WANG Ye School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China SinoProbe Center Chinese Academy of Geological Sciences and China Geological SurveyBeijing 100037China Exploration and Development Research Institute Shengli Oilfield CompanySinopecDongyingShandong 257000China Henan Institute of Geological Survey ZhengzhouHenan 450001China

The North Qilian Shan fold and thrust belt,located at the northern Tibetan Plateau and southern margin of the Hexi Corridor,is a key tectonic unit to decode the formation and expansion of the plateau.Previous studies emphasize the Cenozoic deformation due to the far-field response to the Indo-Asian collision,but the Mesozoic deformations are poorly constrained in this area.We conducted detailed field mapping,structural analysis,geochronology,and structural interpretation of deep seismic reflectional profiling and magnetotelluric(MT)sounding,to address the superposed results of the Mesozoic and Cenozoic deformation.The results recognized the North Qilian thrust and nappe system(NQTS),the root and the frontal belt are the North Qilian thrust(NQT),and the Yumu Shan klippe(YK),respectively.The middle belt is located between the NQT and the YK.Monzonitic granite zircon U-Pb dating from the middle belt yields an age of ca.415 Ma,which is similar to south NQT.The thrusting displacement is estimated at ca.48 km by structural interpretation of deep profiles.The timing is constrained in the early stage of the Early Cretaceous by the formation of simultaneous growth strata.We suggest that the NQTS has resulted from the far-field effect of the Lhasa-Qiangtang collision,and the Yumu Shan is uplifted by the superposed Cenozoic deformation.

关键词： geochronology structural analysis seismic reflectional and MT profiling Early Cretaceous North Qilian thrust and nappe system Tibetan Plateau

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structural analysis OF PEKEKK(T/I) USING WAXD, IMAGING PLATES AND SAXS

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Chinese Journal of Polymer Science 2004年第4期22卷 379-387页

作者：莫志深 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

Structures and crystal form transition of the novel aryl ether ketone polymer containing meta-phenylene linkage: PEKEKK(T/I) were investigated by wide angle X-ray diffraction (WAXD), imaging plates (IPs) and small angle X-ray scattering (SAXS). The energy of activation of the decomposition reaction and degree of crystallinity of PEKEKK(T/I) were determined by WAXD and thermo-gravimetric analysis (TGA), respectively. Results obtained from WAXD and IPs show that crystal forms coexist in the PEKEKK(T/I) samples isothermally cold crystallized in the temperature range from 180'C to 240T? and only form occurs in PEKEKK(TTI) samples isothermally cold crystallized at 2701C. The radius of gyration (Rg), thickness of microregions with electron-density fluctuations (E) and distribution of particle sizes were investigated by SAXS.

关键词： PEKEKK WAXD Imaging plates SAXS structural analysis

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structural analysis AND ENVIRONMENTAL STABILITY OF POLYFLUORINATED GROUP SUBSTITUTED POLYTHIOPHENES

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Chinese Journal of Polymer Science 1996年第4期14卷 330-337页

作者：张旭庆沈学明杨士勇陆伟张景云 Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200232

Electrochemical polymerization of 3-fluoroalkoxy and 3-fluoroether thiophenes gives polymers with relatively high molecular weights and good processibility. Investigation of these polymers by means of GPC indicates that an increase in the number of fluorine atoms in the fluorinated group results in a decrease in degree of polymerization of the polymers in the same polythiophene series. As shown by NMR and FTIR, the polyfluorinated group substituted polythiophenes have regular 2, 5-coupling in their main chains. The SEM micrographs of the polymer films exhibit that polymer (1)-poly [3-2, 2, 3, 3-tetrafluoro-propoxy) thiophene] possesses more regular structure than the other polymers do. Substitution of polythiophenes by fluorinated groups leads to the polymers with high electric, electrochemical and thermal stability.

关键词： structural analysis environmental stability polyfluorinated substituent polythiophene

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structural analysis of Eu_2Mn_(2/3)Ta_ 4/3O_7 with a Pyrochlore-Related Structure

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Journal of Rare Earths 2004年第1期22卷 172-174页

作者：陈刚 Satoh Hirohisa Kamegashira Naoki Department of Applied Chemistry Department of Materials Science

Eu 2Mn 2/3Ta 4/3O 7 specimen was synthesized from Eu 2O 3, MnO and Ta 2O 5 in a reducing atmosphere. Structure analysis was carried out by Rietveld method from X-ray diffraction data. The X-ray diffraction profile calculated with monoclinic C2/c model was in a good agreement with the observed X-ray diffraction patterns since several small peaks of super lattice could be also assigned with C2/c symmetry in addition to fundamental reflection peaks. Eu 2Mn 2/3Ta 4/3O 7 has two kinds of distorted (Mn, Ta)O 6 octahedra and HTB layers, which deviates from the regular forms. Europium atoms coordinate to eight or seven oxygen atoms and lead to two kinds of polyhedra, EuO 8 and EuO 7 in this compound.

关键词： complex oxide structural analysis X-ray diffraction rare earths

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structural analysis of Water-soluble Polysaccharide PIP_1 Extracted from the Cultured Mycelium of Phellinus igniarius

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Chemical Research in Chinese Universities 2006年第6期22卷 708-711页

作者： WU Ming-jiang JIANG De-zhi LIU Tie-mei ZHANG Li-ping School of Life Science Northeast Normal University Changchun 130024 P. R. China School of Life and Environment Science Wenzhou University Wenzhou 325035 P.R. China

Water-soluble crude polyseccharide（PIP） was extracted from cultured mycelium of the fungus Phellinus igniarius. After ethanol precipitation and sepharose CL-6B gel filtration, the fraction of PIP1 was obtained, which was shown to be a homogeneous polysaccharide by means of high-performance liquid chromatography. The structure of PIPt was determined by using several methods. C.,C analysis indicates that PIP1 is composed of the monosaccharides of glucose, galactose, and mannose. Their malar ratio is 3. 70： 4. 06： 1.00. The molar weight was estimated to be 17 kd via HPLC. IR, GC, partial hydrolysis with acid, pefiedate oxidation, Smith degradation, methylation, and GC-MS analysis were used for the structural analyses of PIP1. The results show that PIP1 has a small quantity of branch structure, The main glycosidic linkage of PIP1 has a β-configurafion. The main chain is made up of a large mass of glucose （ 1→3 ） and few mannose （ 1→4 ） ; the side chain is composed of glucose （ 1 →3 ） and galactose （ 1→6 ） ; the nonreduced end is composed of galactose and glucose. The side chains are branched at 6-0 of glucose（ 1→3,6） and mannose（1→4,6）. On an average, there are three branches among 20 residues. It is presumable that the existence of 1,3-linked Glc in the main and side chains is the main reason for its higher antitumor activity.

关键词： Phellinus igniarus Cultured mycelium Polysaccharide structural analysis

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structural analysis and Electrical Property of Tungsten BronzePrepared by Rare Earth Gaseous Permeation

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Journal of Rare Earths 2004年第6期22卷 749-751页

作者：李中华李昕陈刚苏铭汉韦永德 Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China

The cubic sodium tungsten bronzes, Na_xWO_3(x=0.854 and 0.814)were prepared by rare earths gaseous permeation method. structural analysis was carried out by Rietveld method from powder X-ray diffraction data. The X-ray diffraction profile calculated with cubic P32 models are in good agreement with the observed X-ray diffraction patterns. There is only a little difference in W-O bond and Na-O bond between Na_(0.854)WO_3 and Na_(0.814)WO_3. Conductivity measurements indicate that Na_xWO_3 show anomalous semiconducting behavior and percolation model was used to interpret it.

关键词： sodium tungsten bronze rare earths gaseous permeation structural analysis conductivity rare earths

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structural analysis of a RC Shear Wall by Use of a Truss Model

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Open Journal of Civil Engineering 2022年第3期12卷 320-352页

作者： Panagis G. Papadopoulos Periklis E. Lamprou Division of structural Engineering Department of Civil Engineering Aristotle University of Thessaloniki Thessaloniki Greece

Purpose of present work is to develop a reliable and simple method for structural analysis of RC Shear Walls. The shear wall is simulated by a truss model as the bar of a truss is the simplest finite element. An iterative method is used. Initially, there are only concrete bars. Repeated structural analyses are performed. After each structural analysis, every concrete bar exceeding tensile strength is replaced by a steel bar. For every concrete bar exceeding compressive strength, first its section area is increased. If this is not enough, a steel bar is placed at the side of it. For every steel bar exceeding tensile or compressive strength, its section area is increased. After the end of every structural analysis, if all concrete and steel bars fall within tensile and compressive strengths, the output data are written and the analysis is terminated. Otherwise, the structural analysis is repeated. As all the necessary conditions (static, elastic, linearized geometric) are satisfied and the stresses of ALL concrete and steel bars fall within the tensile and compressive strengths, the results are acceptable. Usually, the proposed method exhibits a fast convergence in 4 - 5 repeats of structural analysis of the RC Shear Wall.

关键词： Reinforced Concrete Shear Wall structural analysis Truss Model Iterative Method Computer Program Boundary Columns and Beam Grid of Horizontal and Diagonal Reinforcing Steel Bars

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structural analysis on cutting notch of tea stalk by X-ray micro-computed tomography

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Information Processing in Agriculture 2020年第2期7卷 242-248页

作者： Zhe Du Yongguang Hu Wenye Wu Yongzong Lu Noman Ali Buttar School of Agricultural Equipment Engineering Institute of Agricultural EngineeringJiangsu UniversityChina School of Electrical and Information Engineering Jiangsu UniversityChina School of Agricultural Equipment Engineering Institute of Agricultural EngineeringJiangsu UniversityChina and Department of LandAir and Water ResourcesUniversity of CaliforniaDavisUnited States

Quantitative analysis on cutting notch of tea stalk is one method to better understand shear resistance and mechanical properties of the stalk,which could improve cutting performance and efficiency for tea harvesting.Optimal design of the cutter might be achieved through structural analysis of cutting notch by X-ray micro-computed tomography(micro-CT).The third inter-node of the stalks were sampled and scanned by micro-CT after they were cut at different cutting depths(0.7,1.5,2.3 mm)and cutting edge angles of cutter(30,35,40).The structural change of the cutting notch and cutting force was observed.Grey-scale histogram analysis and bimodal segmentation method were used to extract the information about cutting notch from 2D slice images.A 3D model of the stalk was established with reconstruction and volume rendering.Besides,maximum crosssectional area ratio of cutting notch(MCSARCN)and volume ratio of cutting notch(VRCN)were calculated.The results show that MCSARCN and VRCN had a closely relationship with the cutting force,cutting depth and cutting edge angle according to 3D tomographic images and 2D slice images.Both MCSARCN and VRCN increased with cutting depth,despite of cutting edge angle.For cutting edge angle of 30,35and 40at different cutting depths,MCSARCN increased from 4.89%to 9.47%,from 8.51%to 22.83%and from 4.30%to 16.87%,respectively.Meanwhile,VRCN increased from 1.59%to 2.13%,from 2.98%to 5.76%and from 3.04%to 5.01%,respectively.When cutting depth was 1.5 mm,cutting force increased but VRCN present a decreased trend with cutting edge angle.X-ray micro-CT could be used to analyze the structure on cutting notch of tea stalks which is helpful in optimizing the structural parameters of the cutter.

关键词： Tea stalk Cutting notch X-ray micro-computed tomography structural analysis

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structural analysis of Platforms with the Effect of Joint Flexibility

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China Ocean Engineering 1993年第3期8卷 243-252页

作者： Mu, Yang Zhang, Shengkun Shanghai Jiao Tong Univ Shanghai China

A modified space beam element is presented in this paper to consider the local joint flexibility of T, Y tubular joints subjected to axial forces and in-plane bending moments for analysis of platforms. Two numerical e... 详细信息

关键词： Bending (deformation) Joints (structural components) Loads (forces) Mathematical models Ocean engineering structural analysis Welds

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Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation

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Food Science and Human Wellness 2024年第1期13卷 421-433页

作者： Jingjing Liang Meina Zhang Xiaohan Li Yuan Yue Xiaowei Wang Mengzhen Han Tianli Yue Zhouli Wang Zhenpeng Gao College of Food Science and Engineering Northwest A&F UniversityYangling 712100China Xi'an GaoXin No.1 High School Xi'an 710065China

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.

关键词： Lentinus edodes polysaccharide Lactobacillus fermentum fermentation structural analysis Immunoregulatory activity Nuclear magnetic resonance

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