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The classification and assessment of freeze-thaw erosion in Tibet

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Journal of Geographical Sciences 2007年第2期17卷 165-174页

作者： ZHANG Jianguo LIU Shuzhen YANG Siquan School of Geography Nantong University Nantong 226007 China institute of Mountain Hazards and Environment CAS Chengdu 610041 China National Disaster Reduction Center MCA Beijing 100053 China

Freeze-thaw erosion is the third largest soil erosion type after water erosion and wind erosion. Restricted by many factors, few researches on freeze-thaw erosion have so far been done at home and abroad, especially those on the assessment method of freeze-thaw erosion. Based on the comprehensive analysis of impact factors of free-thaw erosion, this paper chooses six indexes, including the annual temperature range, annual precipitation, slope, aspect, vegetation and soil, to build the model for relative classification of freeze-thaw erosion using weighted and additive methods, and realizes the relative classification of the freeze-thaw erosion in Tibet with the support of GIS software. Then a synthetic assessment of freeze-thaw erosion in Tibet has been carried out according to the relative classification result. The result shows that the distribution of freeze-thaw eroded area is very extensive in Tibet, accounting for 55.3% of the total local land area; the spatial differentiation of freeze-thaw erosion with different intensities is obvious; and the difference in distribution among different regions is also obvious.

关键词： Tibet freeze-thaw erosion GIS classification and assessment

Landslide susceptibility assessment of the region affected by the 25 April 2015 Gorkha earthquake of Nepal

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山地科学学报（英文） 2016年第11期13卷 1941-1957页

作者： Amar Deep Regmi Megh Raj Dhital ZHANG Jian-qiang SU Li-jun CHEN Xiao-qing Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentCASChengdu 610041China Central Department of Geology Tribhuvan UniversityKirtipur 44613Nepal

Nepal was hit by a 7.8 magnitude earthquake on 25^(th) April,*** main shock and many large aftershocks generated a large number of coseismic landslips in central *** have developed a landslide susceptibility map of the affected region based on the coseismic landslides collected from remotely sensed data and fieldwork,using bivariate statistical model with different landslide causative *** the investigation,it is observed that most of the coseismic landslides are independent of previous *** of 3,716 mapped landslides,we used 80% of them to develop a susceptibility map and the remaining 20% were taken for validating the model.A total of 11 different landslide-influencing parameters were *** include slope gradient,slope aspect,plan curvature,elevation,relative relief,Peak Ground Acceleration(PGA),distance from epicenters of the mainshock and major aftershocks,lithology,distance of the landslide from the fault,fold,and drainage *** success rate of 87.66% and the prediction rate of86.87% indicate that the model is in good agreement between the developed susceptibility map and theexisting landslides ***,lithology,slope angle and elevation have played a major role in triggering the coseismic mass *** susceptibility map can be used for relocating the people in the affected regions as well as for future land development.

关键词：地震 Himalaya Coseismic 山崩危险性 bivariate 统计模型尼泊尔

BOUNDARY ELEMENT METHOD FOR SOLVING DYNAMICALRESPONSE OF VISCOELASTIC THIN PLATE(II)──-THEORETICAL ANALYSIS

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Applied Mathematics and Mechanics(English Edition) 1998年第2期19卷 101-110页

作者：丁睿朱正佑程昌钧 Mechanical Postdoctoral Station Southwestern Jiaotong University Chengdu P. R. China Shanghai institute of Applied Mathematics and Mechanics Shanghai P. R. China

In this paper, the necessary theoretical analysis for the approximation boundary element method to solve dynamical response of viscoelastic thin plate presented in [1] ***. The theorem of existence and uniqueness of the approximate solution andthe error estimation are also obtained. Based on these conclusions , the principle forchoosing the mesh size and the number of truncated terms in the fundamental solution are given. It isshown that the theoretical ana analysis in this paper are consistent with thenumerical results in [1].

关键词： dynamic response viscoelasticity approximate boundary elementmethod error estimation

Determination of bilocal field in GCM theory and calculation of some properties of mesons

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Science China Mathematics 1997年第8期40卷 860-867页

作者：吕晓芙刘玉鑫赵恩广 Department of Physics Sichuan UniversityChengdu 610064China institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080China Department of Physics Peking UniversityBeijing 100871China

Through theoretical derivation,the vacuum configuration of the bilocal field in GCM is equivalent to dynamical mass of *** the approximation of instanton dilute liquid,an analytical expression for the vacuum configuration is *** on it,the decay constants and masses of π and σ mesons are *** results are much more improved than those given by the previous GCM calculations.

关键词： quantum chromodynamics GCM theory bilocal field vacuum configuration meson property.

A Semi-Blind Method to Estimate the I/Q Imbalanc of THz Orthogonal Modulator

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China Communications 2021年第5期18卷 202-209页

作者： Juan Liu Ge Liu Qiuyu Wu Ying Wang He Yue Changxing Lin Xianjin Deng Microsystem and Terahertz Research Center China Academy of Engineering Physics(CAEP)Chengdu 610200China institute of Electronic Engineering China Academy of Engineering Physics(CAEP)Mianyang 621900China

In terahertz communication,the direct frequency conversion structure in which orthogonal mixer is the main frequency conversion unit,makes engineers get into trouble of in-phase(I)branch and quadrature(Q)branch imbalance,carrier wave leakage,*** damages result in system performance tremendous *** proposed a semiblind method to estimate the I/Q imbalance of THz orthogonal modulator,based on predefined preamble and pilot symbols for quadrature amplitude modulation(QAM).In this paper,a transmitter with Y band quadrature mixer and 20Gbps base-band signal has been *** bandwidth of the baseband signal was 7GHz,and the modulation type was *** this method,7dB improvement of the system’s symbol Mean Square Error(MSE)has been *** means the proposed method can be used to eliminate the I/Q imbalance effectively.

关键词： terahertz communication quadrature modulator I/Q imbalance correction digital signal processing

Illite Crystallinity Mapping of Very Low Grade Metamorphism of Triassic Metapelites in the Zoigê Area,Western China

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 96-105页

作者： TANG Yan SANG Longkang YUAN Yanming YU Jishun ZHANG Yunpeng QI Xianmao YANG Yunlong Faculty of Earth Sciences China University of GeosciencesWuhan 430074China College of Earth Science and Resources Chang'an UniversityXi'an 710054China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China Xi'an Center of Geological Survey China Geological SurveyXi'an 710054China chengdu institute of Geology and Mineral Resources Chengdu 610082China Sinopec Exploration Southern Company Chengdu 610082China

X-ray diffraction methods for estimating the metamorphic grade of diagenetic, anchizone and epizone in metapelites are reviewed and applied to samples from a 7000 m＋ borehole in western China and surface samples from the surrounding Zoige area. Kiibler＇s illite crystallinity （IC） measurements provide more consistent results than calculated values of percentage of illite in the I/S mixed layers and percentage of I/S mixed layers. Down-borehole IC values display a typical burial metamorphic relationship between stratigraphic level and IC. A method for preparing very low grade metamorphic maps is described, and isograds plotted on a regional geological map at selected values of IC, delineating a high temperature diagenetic zone, an anchizone, and an epizone. The map shows that IC values are controlled by stratigraphic level in the north of the study area （i.e. burial metamorphism）, and proximity to an igneous intrusive body in the south （i.e. contact metamorphism）.

关键词： X-ray diffraction metapelitic zone illite crystallinity percentage of illite in I/S mixed layers percentage of I/S mixed layers the metamorphic map

The spatial distribution characteristics of shallow fissures of a landslide in the Wenchuan earthquake area

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Journal of Mountain Science 2016年第9期13卷 1544-1557页

作者： XU Xing-qian Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of SciencesChengdu 610041China institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Shallow fissures, being the main infiltration paths of fluid on the surface of a slope, played an important role in the whole process of a landslide. However, the spatial distribution characteristics of fissures in the slope are difficult to be determined. In this study, we attempted to characterize the variation pattern of slope fissures along depth in the Wenchuan earthquake area in Sichuan Province by combining engineering geological investigation, geomorphologic analysis and geophysical investigation. The geophysical methods that were used in this study include Multichannel Analysis of Surface Wave(MASW), Ground Penetrating Radar(GPR) and Electrical Resistivity Tomography(ERT). The results suggested that geophysical parameters(shear wave velocity, electromagnetic signals attenuation and resistivity) could provide valuable information for the spatial network of shallow fissures. Through the verification by engineering geological survey and geophysical sensitivity analysis, this work highlighted that MASW was the most appropriate technique to delineate the propagation of shallow fissures in a gravel soil slope.

关键词：空间分布特征裂缝扩展地震区浅层滑坡汶川电阻率层析成像地球物理方法

Reef-controlled Mineral Deposits in Southern China

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Acta Geologica Sinica(English Edition) 1989年第3期63卷 241-252页

作者： Zeng Yunfu and Tian Hongjun chengdu College of Geology, chengdu chengdu College of Geology Chengdu 1This paper was based on the related research results achieved in recent years by the institute of Sedimentology of chengdu College of Geology. Besides the authors Zhang Jinquan Zheng Rongcai Xu Xinhuang Tang Dezhang Geng Aiqin Yang Weidong and Chen Zhihong also made large amounts of work. The authors also used the data of Zhou Huailing Shi Huanqi and Hu Chunsheng of the Guangxi Bureau of Geology and Mineral Resources.

Reef-controlled mineral deposits in southern China are divided into three types in this paper based on the relative importance of organic reefs in the ore-forming processes; they are: the direct type, indirect type, and passive type. The case histories of several typical deposits are discussed. In studying reef-controlled deposits, more attention should be paid to the function of synsedimentary faults in reef construction and mineralization and the importance of oil-gas palaeoreservoirs in reef rocks for the formation of sulfide deposits, in addition to analysing the favourable sedimentary facies of mineralization.

关键词： Reef-controlled Mineral Deposits in Southern China

Protective effects of sodium butyrate on rotavirus inducing endoplasmic reticulum stress-mediated apoptosis via PERK-eIF2αsignaling pathway in IPEC-J2 cells

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Journal of Animal Science and Biotechnology 2021年第4期12卷 1543-1554页

作者： Ye Zhao Ningming Hu Qin Jiang Li Zhu Ming Zhang Jun Jiang Manyi Xiong Mingxian Yang Jiandong Yang Linyuan Shen Shunhua Zhang Lili Niu Lei Chen Daiwen Chen College of Animal Science and Technology Sichuan Agricultural UniversityHuimin Road 211#ChengduSichuan Province 611130P.R.China institute of Animal Nutrition Sichuan Agricultural UniversityHuimin Road 211#ChengduSichuan Province 611130P.R.China Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education Sichuan Agricultural UniversityChengduSichuan 611130P.R.China

Background:Rotavirus(RV)is a major pathogen that causes severe gastroenteritis in infants and young *** reticulum(ER)stress and subsequent apoptosis play pivotal role in virus ***,the protective mechanisms of intestinal damage caused by RV are poorly defined,especially the molecular pathways related to enterocytes ***,the aim of this study was to investigate the protective effect and mechanism of sodium butyrate(SB)on RV-induced apoptosis of IPEC-J2 ***:The RV infection led to significant cell apoptosis,increased the expression levels of ER stress(ERS)markers,phosphorylated protein kinase-like ER kinase(PERK),eukaryotic initiation factor 2 alpha(eIF2α),caspase9,and *** PERK pathway using specific inhibitor GSK subsequently reversed RV-induced cell *** SB treatment significantly inhibited RV-induced ERS by decreasing the expression of glucose regulated protein 78(GRP78),PERK,and eIF2α.In addition,SB treatment restrained the ERS-mediated apoptotic pathway,as indicated by downregulation of C/EBP homologous protein(CHOP)mRNA level,as well as decreased cleaved caspase9 and caspase3 protein ***,siRNA-induced GPR109a knockdown significantly suppressed the protective effect of SB on RV-induced cell ***:These results indicate that SB exerts protective effects against RV-induced cell apoptosis through inhibiting ERS mediated apoptosis by regulating PERK-eIF2αsignaling pathway via GPR109a,which provide new ideas for the prevention and control of RV.

关键词： Apoptosis IPEC-J2 PERK-eIF2α Rotavirus Sodium butyrate