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Journal of Geographical Sciences 2022年第4期32卷 605-616页

作者： CAO Liguo ZHOU Zhengchao WANG Ning xiao shun School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China

Due to the atmospheric nuclear weapon tests carried out,terrestrial environments have been extensively contaminated by global fallout of plutonium(Pu)***^(239+240)Pu inventories in soil profiles from undisturbed and flat forest or grasslands(reference sites)mainly from Europe and Asia are considered as important background for evaluating soil ***,we conducted a literature survey over an area extending from 2.6°W to 148.9°E and from 53.2°S to 76.6°N,with the purpose of analyzing the spatial distribution of^(239+240)Pu inventories and possible controlling *** aim of this work was to derive an empirical model of^(239+240)Pu inventory based on currently available^(239+240)Pu data,precipitation and *** results show that,in general,the latitudinal distribution of^(239+240)Pu inventory was consistent with the UNSCEAR ***,the^(239+240)Pu inventories are higher than the UNSCEAR data,especially in the Northern *** addition,close relationships(at the 0.01 significance level)were identified between^(239+240)Pu inventories and annual precipitation and *** empirical formula was therefore developed to estimate^(239+240)Pu inventories in soils based on latitude and precipitation ***,future research may require more data of measured^(239+240)Pu inventories in soil profiles that can be used to compare,validate and improve upon the accuracy of the inferred empirical equation.

关键词： spatial distribution plutonium global fallout precipitation

Efficient tensor decomposition method for noncircular source in colocated coprime MIMO radar

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Chinese Physics B 2020年第5期29卷 333-345页

作者： Qian-Peng Xie xiao-Yi Pan shun-Ping xiao National University of Defense Technology Changsha 410073China

An effective method via tensor decomposition is proposed to deal with the joint direction-of-departure(DOD)and direction-of-arrival(DOA)estimation of noncircular sources in colocated coprime MIMO *** decomposing the transmitter and receiver into two sparse subarrays,noncircular property of source can be used to construct new extended received signal model for two sparse *** new received model can double the virtual array aperture due to the elliptic covariance of imping sources is *** further exploit the multidimensional structure of the noncircular received model,we stack the subarray output and its conjugation according to mode-1 unfolding and mode-2 unfolding of a third-order tensor,***,the corresponding extended tensor model consisted of noncircular information for DOA and DOD can be ***,the higher-order singular value decomposition technique is utilized to estimate the accurate signal subspace and angular parameter can be automatically paired via the rotational invariance ***,the ambiguous angle can be eliminated and the true targets can be achieved with the aid of the coprime ***,a closed-form expression for the deterministic CRB under the NC sources scenario is also *** results verify the superiority of the proposed estimator.

关键词： colocated coprime MIMO radar noncircular signal tensor decomposition DOD and DOA estimation

Biocompatible in situ-forming glycopolypeptide hydrogels

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Science China(Technological Sciences) 2020年第6期63卷 992-1004页

作者： SHI shun YU ShuangJiang LI Gao he ChaoLiang CheN XueSi CAS Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China College of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Jilin Biomedical Polymers Engineering Laboratory Changchun 130022China

A lack of biological activity hinders the application of synthetic hydrogels in tissue engineering and regenerative ***,the use of glycopolypeptides in hydrogel synthesis may provide the materials with the desired biological ***,we prepared three in situ-forming hydrogels from various phenol-functionalized *** gelation time,mechanical properties,degradation properties,and biocompatibility of the hydrogels were *** time ranged from 11 to 380s,depending on the concentration of horseradish *** galactose-modified polypeptide hydrogel showed the highest storage modulus with an obvious stress relaxation *** prepared hydrogels exhibited good degradation properties and compatibility to cells and ***,the rate of immune cell accumulation around the mannosemodified polypeptide hydrogel was the fastest among the hydrogels.

关键词： in situ-forming hydrogels glycopolypeptide tissue engineering horseradish peroxidase

Synthesis and Structural Characterization of Chiral [(n-Bu)_4N]_2[Mo_2O_5(OC_(10)H_6O)_2]

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Chemical Research in Chinese Universities 2002年第2期18卷 228-232页

作者： LU xiao-ming ZHOU Yin-zhaung LIU shun-cheng MAO Xian BU Xian-he Wuhan Institute of Physics and Mathematics Chinese Academy of ScienceWuhan 431714.P.R.China Department of Chemistry Capital Narmal UniversityBeijing 100037P.R.China Department of Chemistry Nankai UniversityTianjin 300071P.R.China

The expension of the coordination chemistry of polyoxomolybdates is attributed to the solubility of the polyoxometallic anions in organic solvents and coordination ability of them as characteristic metal ligands in organo-metallic reactions, for example, the study of catalysis mechanism based upon organo-polyoxomolybdate derivatives~[1-3]. Various coordination modes have been reported for binuclear molybdenum-oximate complexes, such as [ Mo_2O_3 ]~(4+), [ MoA ]~(2+), [ Mo_2O_6 ]~° and [Mo_2O_5]~(2+[4-6]). But it is rarely to find the report on binuclear molybdate dinegative anion with the geometry of two face-shared MoO_6 octahedra coordinated with the oxomate ligand.

关键词： 2.3-Dihydroxynaphthalene Binuclear Tetranuelear Organo-molybdate derivative Crystal

Chemical characteristics of PM_(2.5) during dust storms and air pollution events in Chengdu,China

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Particuology 2013年第1期11卷 70-77页

作者： Qiyuan Wang Junji Cao Zhenxing Shen JunTao shun xiao Lei Luo Qingyang he Xinying Tang Department of Environmental Science and Engineering Xi'an Jiaotong University Key Lab of Aerosol Science & Technology SKLLQGInstitute of Earth EnvironmentChinese Academy of Sciences Institute of Global Environmental Change Xi'an Jiaotong University South China Institute of Environmental Sciences SEPA Meteorological Bureau of Baoji Municipality Climate Center of Shaanxi Meteorological Bureau Institute of Plateau Meteorology CMA Institute of Plateau Meteorology CMAChengdu

Daily fine particulate （PM2.5） samples were collected in Chengdu from April 2009 to February 2010 to investigate their chemical profiles during dust storms （DSs） and several types of pollution events, including haze （HDs）, biomass burning （BBs）, and fireworks displays （FDs）. The highest PM2.5 mass concentrations were found during DSs （283.3 μg/m^3）, followed by FDs （212.7 μg/m^3）, HDs （187.3 μg/m^3 ）, and BBs （130.1 μ g/m^3）. The concentrations of most elements were elevated during DSs and pollution events, except for BBs. Secondary inorganic ions （NO3^- , SO4^2-, and NH4^＋） were enriched during HDs, while PM2.5 from BBs showed high K^＋ but low SO4^2- , FDs caused increases in K^＋ and enrichment in SO4^2-. Ca^2＋. was abundant in DS samples, Ion-balance calculations indicated that PM2.5 from HDs and FDs was more acidic than on normal days, but DS and BB particles were alkaline. The highest organic carbon （OC） concentration was 26.1 μg/m^3 during FDs, followed by BBs （23.6 μg/m^3 ）, HDs （19.6 μg/m^3 ）, and DSs （18.8 μg/m^3 ）. In contrast, elemental carbon （EC） concentration was more abundant during HDs （10.6μg/m^3） and FDs （9.5 μg/m^3） than during BBs （6.2μg/m^3） and DSs （6.0 μg/m^3）. The highest OC/EC ratios were obtained during BBs, with the lowest during HDs. SO4^2＋ /K^＋ and TCA/SO4^2- ratios proved to be effective indicators for differentiating pollution events. Mass balance showed that organic matter, SO4^2-, and NO3^- were the dominant chemical components during pollution events, while soil dust was dominant during DSs.

关键词： PM2.5 Chemical species Pollution events Mass balance

Oscillation quenching and physical explanation on freeplay-based aeroelastic airfoil in transonic viscous flow

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Chinese Journal of Aeronautics 2023年第10期36卷 124-136页

作者： Yayun SHI shun he Gaowei CUI Gang CheN Yan LIU State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Beijing Institute of Structure and Environment Engineering Beijing 100076China Shenyang Aircraft Design Institute Shenyang 110036China

Limit Cycle Oscillation(LCO)quenching of a supercritical airfoil(NLR 7301)considering freeplay is investigated in transonic viscous *** Fluid Dynamics(CFD)based on Navier-Stokes equations is implemented to calculate transonic aerodynamic forces.A loosely coupled scheme with steady CFD and an efficient graphic method are developed to obtain the aerodynamic *** quenching phenomenon is observed from the nonlinear dynamic aeroelastic response obtained by using time marching *** the airspeed increases,LCO appears then quenches,forming the first LCO *** the quenching region,LCO occurs again and sustains until the divergence of the response,forming the second LCO *** quenching of LCOs was addressed physically based on the aerodynamic preload and the linear flutter ***“island”of stable region is observed in the flutter boundary,*** flutter speed versus the mean Angle of Attack(AoA).The LCO quenches when the aerodynamic preload crosses this stable region with the increasing of *** LCO quenching of this model in transonic flow is essentially induced by destabilizing effect from aerodynamic preload,since the flutter speed is sensitive to AoA due to aerodynamic nonlinearity.

关键词： Freeplay Nonlinear aeroelasticity Supercritical airfoil Transonic flutter Unsteady flow

Experiencing winter for spring flowering: A molecular epigenetic perspective on vernalization

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Journal of Integrative Plant Biology 2020年第1期62卷 104-117页

作者： xiao Luo Yuehui he National Key Laboratory of Plant Molecular Genetics & Shanghai Center for Plant Stress Biology Center for Excellence in Molecular Plant Sciences The Chinese Academy of Sciences

Many over-wintering plants, through vernalization, overcome a block to flowering and thus acquire competence to flower in the following spring after experiencing prolonged cold exposure or winter cold. The vernalization pathways in different angiosperm lineages appear to have convergently evolved to adapt to temperate climates. Molecular and epigenetic mechanisms for vernalization regulation have been well studied in the crucifer model plant Arabidopsis ***, we review recent progresses on the vernalization pathway in Arabidopsis. In addition, we summarize current molecular and genetic understandings of vernalization regulation in temperate grasses including wheat and Brachypodium, two monocots from Pooideae, followed by a brief discussion on divergence of the vernalization pathways between Brassicaceae and Pooideae.

关键词： winter spring temperate

Combined liver and kidney transplantation in Guangzhou,China

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hepatobiliary & Pancreatic Diseases International 2007年第6期6卷 585-589页

作者： Zhu, xiao-Feng he, xiao-shun Chen, Gui-Hua Chen, Li-Zhong Wang, Chang-Xi Huang, Jie-Fu Sun Yat Sen Univ Affiliated Hosp 1 Organ Transplantat Ctr Guangzhou 510080 Peoples R China Sun Yat Sen Univ Affiliated Hosp 3 Organ Transplantat Ctr Guangzhou 510080 Peoples R China

BACKGROUND: When liver or kidney transplant can respectively cure end-stage liver or kidney disease, neither hepatic graft nor renal transplant alone can be used as a radical therapy for diseases which involve both liver and kidney. Combined liver and kidney transplantation commenced late in China, and the number of transplants has been limited. This study was designed to assess the effects of simultaneous combined liver and kidney transplantation (SLKT) on end-stage liver and kidney diseases. METHODS: Fifteen patients who had received SLKT from 1996 to 2006 in the First Affiliated Hospital of Sun Yat-Sen University were reviewed. They included 5 patients with polycystic liver and kidney, 5 patients with hepatic cirrhosis and renal failure, and 5 patients with fulminant hepatic failure and hepatorenal syndrome (11 men and 4 women; average age 43.5 years). All patients had combined liver and kidney transplantation. RESULTS: The 5 patients with polycystic liver and kidney have survived for more than one year after SLKT, and the longest survival has been 5 years. Three of the 5 patients with hepatic cirrhosis and renal failure have survived more than two years; one died perioperatively and the other died from recurrence of hepatitis B 18 months after the operation. Three of the 5 patients with fulminant hepatic failure and hepatorenal syndrome have survived for two years, and 2 died of multiple organ failure during the operation. CONCLUSIONS: SLKT is an effective therapy for end-stage liver and kidney disease but the indications of SLKT for hepatorenal syndrome should be strict. SLKT may immunologically protect the renal graft.

关键词： combined liver and kidney transplantation polycystic liver and kidney hepatorenal syndrome fulminant hepatitis

Implementation of Enterprises Interoperation Based on Ontology

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International Journal of Automation and computing 2010年第3期7卷 303-309页

作者： xiao-Feng Di Yu-shun Fan Department of Automation Tsinghua University Beijing 100084 PRC

The interoperation among enterprises in e-business could block the ambient semantic collaboration and cause a big problem since varying information descriptions and different data models may be used in different enterprises＇ information systems. Ontology is an important tool to overcome the above mentioned syntax and semantic misunderstanding problem. Our goal is to provide a user-friendly environment supporting syntax and neutral format data model for business information. In this paper, two scenarios are discussed and a unified description of data model is developed to solve the gap in interoperation through mapping from logical data of enterprise＇s information system. It provides the methods to realize the mapping among different types of data or information. First, database and other types of information are transformed into neutral format that are described by web ontology language （OWL）. Second, the neutral format can be mapped into the semantic entities and semantic linking through the process of extraction and annotation and added into ontology and then described in a standard format that makes the collaboration be understood easily.

关键词： Interoperation semantic ontology mapping web ontology language (OWL).

La_2Zr_2O_7 TBCs toughened by Pt particles prepared by cathode plasma electrolytic deposition

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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 704-715页

作者： shun-jie Deng Peng Wang Ye-dong he Jin Zhang Institute for Advanced Materials and Technology University of Science and Technology Beijing

La2Zr2O7 thermal barrier coatings（TBCs） with dispersed Pt particles were prepared by cathode plasma electrolytic deposition（CPED） with ceramic balls added to the cathode region. Compared with the conventional CPED, when ceramic balls are used in the cathode region, the plasma discharge ignition current density decreases approximately 62-fold and the stable plasma discharges occur at the whole cathode surface. Such TBCs with a thickness of 100 μm exhibit a crack-free surface and are composed of pyrochlore-structured La2Zr2O7. Cyclic oxidation, scratching, and thermal insulation capability tests show that such TBCs not only exhibit high resistance to oxidation and spallation but also provide good thermal insulation. These beneficial effects are attributed to the excellent properties of TBCs, such as good thermal insulation because of low thermal conductivity, high-temperature oxidation resistance because of low-oxygen diffusion rate, and good mechanical properties because of the toughening effect of Pt particles.

关键词： thermal barrier coatings platinum oxidation resistance toughening electrolytic deposition