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Quaternary Stratigraphic Division and Paleoenvironmental Evolution Observed from Core LZK1 on Hengsha Island, Shanghai

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Acta Geologica Sinica(English Edition) 2020年第4期94卷 1167-1177页

作者： ke Xue XIE Jianlei ZHANG Zongyan zou Yarui WANG Guoquan Institute of Geological Survey China University of GeosciencesWuhan 430074China State key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China Shanghai Institute of Geological Survey Shanghai 200072China Wuhan Center China Geological SurveyWuhan 430205China Hubei Institute of Geosciences Wuhan 430034China Department of Earth and Atmospheric Sciences University of HoustonHoustonTX 77204USA

The Quaternary sediments in the Yangtze delta are loose and lack precise stratification marks in the lithology. Moreover, due to the limitations of dating methods, it is difficult for Quaternary cores to deliver accurate age constraints. Thus, it is a challenge to establish the Quaternary stratigraphic framework. Gravity core LZK1 was drilled on Hengsha Island, Shanghai, in the Yangtze delta, in 2012. The core was terminated at 403.83 m below the local land surface, the uppermost 291.2 m comprising a thick sequence of Quaternary sediments. This study investigated the stratigraphic subdivision and paleoenvironmental change of the Quaternary sediments. From bottom to top, the Quaternary stratigraphic sequence can be subdivided into the lower Pleistocene Anting Formation, Middle Pleistocene Jiading Formation, Upper Pleistocene Chuansha Formation and Nanhui Formation, Holocene Loutang Formation, Shanghai Formation, and Rudong Formation. According to this study, the Hengsha Island area was dominated by a freshwater lacustrine environment during the early Pleistocene, an alternation of shallow lake and shore lake environment during the Middle Pleistocene, a delta plain to lagoonal environment during the early Upper Pleistocene, a fluvial channel to floodplain environment from the LGM(Last Glacial Maximum) to the end of the Upper Pleistocene, and a delta environment during the Holocene.

关键词： chronostratigraphic framework paleoenvironmental evolution marine transgression Quaternary Yangtze delta

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Inhibition of Abnormal Grain Growth in Stir Zone via In‑Situ Intermetallic Particle Formation During Friction Stir Welding of AA6061

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Acta Metallurgica Sinica(English Letters) 2023年第4期36卷 597-610页

作者： Xin zou Cunli Liu Muyang Deng Ji Chen Lanting Zhang ke Chen School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai key Laboratory of Material Laser Processing and Modification Shanghai Jiao Tong UniversityShanghai 200240China Shanghai-FANUC Robotics CO. LTDShanghai 201906China

Abnormal grain growth(AGG)has been widely observed in many friction stir welded(FSWed)joints during post-weld heat treatment(PWHT).The coarse grain structure not only reduces the strength of the joint but also limits its usage in superplastic *** methods have been reported in previous studies to inhibit AGG,but all of them can only mitigate *** inhibition of AGG was not *** the current research,AGG was widely observed during the PWHT of friction stir welded ***-pass FSW enhanced the thermal stability of the as-welded grain structure but did not eliminate the occurrence of AGG.A new welding method was developed with the ball-milled Al–Ti powder mixture introduced into the stir zone and proved effective in inhibiting AGG in FSWed AA6061 during *** adoption of 5-pass FSW with an alternate rotation mode succeeded in producing an AGG-free *** characterizations conducted in the stir zone showed an evolution of Al–Ti powder mixture into different particle formations and Al3Ti new *** analysis of the second phase particles(SPPs)in the stir zone confirmed the increases in both particle number and average *** quantitative results fit well with Humphreys’grain growth model,which theoretically explains the mechanism for AGG inhibition,i.e.,the significantly enhanced particle pinning effect.

关键词： Abnormal grain growth Friction stir welding AA6061 Second phase particle Particle pinning

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Comparison of surface water extraction performances of different classic water indices using OLI and TM imageries in different situations

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Geo-Spatial Information Science 2015年第1期18卷 32-42页

作者： ke ZHAI Xiaoqing WU Yuanwei qin Peipei DU Yantai Institute of Coastal Zone Research Chinese Academy of Sciences17 Chunhui RoadYantai264003China Department of Microbiology and Plant Biology Center for Spatial AnalysisUniversity of OklahomaNormanOklahomaUSA University of Chinese Academy of Sciences 19 Yuquan RoadBeijing100049China

Recently,water extraction based on the indices method has been documented in many studies using various remote sensing data *** them,Landsat satellites data have certain advantages in spatial resolution and *** the successful launch of Landsat 8,the Operational Land Imager(OLI)data from the satellite are getting more and more attention because of its new *** this study,we used the OLI imagery data source to study the water extraction performance based on the Normalized Difference Vegetation Index,Normalized Difference Water Index,Modified Normalized Water Index(MNDWI),and Automated Water Extraction Index(AWEI)and compared the results with the Thematic Mapper(TM)imagery *** test sites in Tianjin City of north China were selected as the study area to verify the applicability of OLI data and demonstrate its advantages over TM *** found that the results of surface water extraction based on OLI data are slightly better than that based on TM in the two test sites,especially in the city *** AWEI and MNDWI indices performs better than the other two indices,and the thresholds of water indices show more stability when using the OLI ***,it is suitable to combine OLI imagery with other Landsat sensor data to study water changes for long periods of time.

关键词： water extraction operational land imager(OLI)data threshold stability water indices

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Origin of singlet self-trapped exciton and enhancement of photoluminescence quantum yield of organic–inorganic hybrid antimony(III)chlorides with the[SbCl_(5)]^(2)−units

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Nano Research 2023年第11期16卷 12680-12688页

作者： Tao Huang ke Li Jinyu Lei Quan Niu Hui Peng Bingsuo zou State key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures School of ResourcesEnvironmental and MaterialsGuangxi UniversityNanning 530004China State key Laboratory of Luminescent Materials and Devices School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640China

Sb-based organic–inorganic hybrid metal halides(OIHMHs)with[SbCl5]2−units have been widely reported due to high photoluminescence quantum yield(PLQY)and occasional multiple self-trapped exciton(STE)emission bands mainly out of singlet and triplet states,and their multi-band emission is important in white light-emitting diode(WLED).However,not all these OIHMH compounds can produce both emissions out of singlet STE and triplet STE at room temperature *** is crucial to consider how the singlet STE generates and retains to emit light at room temperature for this material’s design and ***,a strategy is proposed that can significantly lift Sb halide PLQY by synthesizing two Sb-based OIHMHs using organic amine cations of different-sized and-quantity,which modulate the distance of neighboring emission ***,the occurrence of singlet STE emission is found to be closely related to the distance of[SbCl_(5)]^(2)−units and local unit distortion in the *** larger distance can produce smaller local distortions,favoring the formation of the singlet STE emission band at higher *** is the first work to reveal the relationship between the local structure and the origin of the singlet STE emission band,providing new insights into the modulation of the Sb-based OIHMH’s emission.

关键词： antimony halide self-trapped exciton M-Xn cluster separation structure distortion

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New perspective on the natural course of chronic HBV infection

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Frontiers of Medicine 2014年第2期8卷 129-134页

作者： Yong-Yuan Zhang ke-qin Hu Zhongping Duan HB Vtech LLC 13901 Lullaby RD Germantown MD 20874 USA Division of Gastroenterology and Hepatology University of California Irvine School of Medicine Orange CA 92868 USA You An Hospital Capital Medical University Beijing 100069 China

Chronic hepatitis B virus （HBV） infection is a significant threat to public health and an enormous burden on society. Mechanisms responsible for chronic HBV infection remain poorly understood. A better understanding of the natural course of chronic HBV infection may shed new light on the mechanisms underlying this disease and help in designing new antiviral strategies. Natural course of chronic HBV infection is conventionally viewed as an uninterrupted process that is usually marked by HBV e antigen （HBeAg） seroconversion or characterized by different phases associated with assumed host responses to HBV infection. However, none of these descriptions captures or highlights the core events that determine the natural course of chronic HBV infection. In this review, we briefly present the current knowledge on this subject and explain the significance and implication of events that occur during infection. A pre-core mutant becomes predominant in the viral population following elimination of the wild-type virus in duck hepatitis B virus-chronically infected animals. The coupled events in which first there is viral clearance that clears wild-type virus and then there is the reinfection of wild-type virus cleared livers with mutant virus are highly relevant to understanding of the natural course of chronic HBV infection under both treated and untreated conditions. In our new perspective, a general natural course of chronic HBV infection comprises cycles of viral clearance and reinfection, and such cycles prolong the chronic HBV infection course. Reviewing published data on the natural course of chronic HBV infection can reduce the possibility of missing important points in the initial data interpretation.

关键词： hepatitis B virus chronic HBV infection natural course hepatitis B seroconversion

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Oblique and Herringbone Buckling Analysis of Steel Strip by Spline FEM

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Journal of Iron and Steel Research International 2011年第9期18卷 21-26页

作者： qin Jian ZHANG qing-dong HUANG ke-fu College of Engineering Peking University Beijing 100871 China Mechanical Engineering School University of Science and Technology Beijing Beijing 100083 China

The tilted waves in steel strip during rolling and leveling of sheet metal can be classified into two different types of buckling, oblique and herringbone buckling, respectively. Numerical considerations of oblique and herringbone buckling phenomena are dealt with by the spline finite element method （FEM）. It is pointed out that the shear stress due to residual strains caused by the rolling process or applied non-uniform loading is the main reason of oblique and herringbone buckle. According to the analysis of stress distribution in plane, the appropriate initial strain patterns are adopted and the corresponding buckling modes are calculated by the spline FEM. The developed numerical model provides an estimation of buckling critical load and wave configuration.

关键词： steel strip spline FEM initial strain oblique buckling herringbone buckling

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Gauss Sum of Index 4:(2)Non-cyclic Case

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Acta Mathematica Sinica,English Series 2006年第3期22卷 833-844页

作者： Jing YANG Shi Xin LUO ke qin FENG Department of Mathematical Science Tsinghua University

Assume that m ≥ 2, p is a prime number, （m,p（p - 1）） = 1,-1 not belong to 〈p〉 belong to （Z/mZ）^＊ and [（Z/mZ）^＊：〈p〉]=*** this paper, we calculate the value of Gauss sum G（X）=∑x∈F^＊x（x）ζp^T（x） over Fq,where q=p^f,f=φ（m）/4,x is a multiplicative character of Fq and T is the trace map from Fq to *** our assumptions,G（x） belongs to the decomposition field K of p in Q（ζm） and K is an imaginary quartic abelian unmber *** the Galois group Gal（K/Q） is cyclic,we have studied this cyclic case in anotyer paper：＂Gauss sums of index four：（1）cyclic case＂（accepted by Acta Mathematica Sinica,2003）.In this paper we deal with the non-cyclic case.

关键词： Gauss sum Stickelberger Theorem Davenport-Hawse formula class number of imaginary quadratic field

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Denoising Graph Inference Network for Document-Level Relation Extraction

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Big Data Mining and Analytics 2023年第2期6卷 248-262页

作者： Hailin Wang ke qin Guiduo Duan Guangchun Luo School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China School of Computing and Artificial Intelligence Southwestern University of Finance and EconomicsChengdu 611130China

Relation Extraction(RE)is to obtain a predefined relation type of two entities mentioned in a piece of text,e.g.,a sentence-level or a document-level *** existing studies suffer from the noise in the text,and necessary pruning is of great *** conventional sentence-level RE task addresses this issue by a denoising method using the shortest dependency path to build a long-range semantic dependency between entity ***,this kind of denoising method is scarce in document-level *** this work,we explicitly model a denoised document-level graph based on linguistic knowledge to capture various long-range semantic dependencies among *** first formalize a Syntactic Dependency Tree forest(SDT-forest)by introducing the syntax and discourse dependency ***,the Steiner tree algorithm extracts a mention-level denoised graph,Steiner Graph(SG),removing linguistically irrelevant words from the *** then devise a slide residual attention to highlight word-level evidence on text and ***,the classification is established on the SG to infer the relations of entity *** conduct extensive experiments on three public *** results evidence that our method is beneficial to establish long-range semantic dependency and can improve the classification performance with longer texts.

关键词： Relation Eextraction(RE) document-level denoising linguistic knowledge attention mechanism

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Influence of splanchnic vascular infusion on the content of endotoxins in plasma and the translocation of intestinal bacteria in rats with acute hemorrhage necrosis pancreatitis

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World Journal of Gastroenterology 2000年第4期6卷 577-580页

作者： qin RY zou SQ Wu ZD Qiu FZ Tongji Med Univ Tongji Hosp Dept Surg Wuhan 430030 Hubei Province Peoples R China

The main reason for the death of the patient with acute hemorrhage necrosis pancreatitis (AHNP) is pancreatic infection and multi-organ failure caused by endotoxemia and intestinal bacterial translocation[1-7]. However, the pathogenesis of endotoxemia and intestinal bacterial translocation remains a question[8-10]; moreover, no effective method of prevention and cure for it has been found till now[11 -15] In the present study, we infused low dose dopamine and low molecular weight dextran through the catheters to abdominal aorta and portal vein, and observed its influence on the endotoxin concentration in plasma and the rate of translocation of intestinal bacteria in AHNP rats.

关键词： acute hemorrhage necrosis pancreatitis microcirculation/splanchnic organ endotoxins/plasma intestinal bacterial translocation

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Gauss Sum of Index 4:(1)Cyclic Case

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1425-1434页

作者： ke qin FENG Jing YANG Shi Xin LUO Department of Mathematical Science Tsinghua University Beijing 100084 P. R. China

Let p be a prime, m ≥ 2, and （m,p（p - 1）） = 1. In this paper, we will calculate explicitly the Gauss sum G（X） = ∑x∈F＊qX（x）ζ^Tp^（x） in the case of [（Z/mZ）＊：（p）] = 4, and -1 （不属于）（p）, wher... 详细信息

Let p be a prime, m ≥ 2, and （m,p（p - 1）） = 1. In this paper, we will calculate explicitly the Gauss sum G（X） = ∑x∈F＊qX（x）ζ^Tp^（x） in the case of [（Z/mZ）＊：（p）] = 4, and -1 （不属于）（p）, where q P^f, f =φ（m）/4, X is a multiplicative character of Fq with order m, and T is the trace map for Fq/Fp. Under the assumptions [（Z/mZ）＊：（p）] = 4 and 1（不属于）（p）, the decomposition field of p in the cyclotomic field Q（ζm） is an imaginary quartic （abelian） field. And G（X） is an integer in K. We deal with the case where K is cyclic in this oaDer and leave the non-cvclic case to the next paper.

关键词： Gauss sum Stickelberger theorem Davenport-Hasse formula cyclic quartic number field

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