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INTEGRATED RISK ASSESSMENT OF MAJOR METEOROLOGICAL DISASTERS WITH PAPRIKA PEPPER IN HAINAN PROVINCE

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Journal of Tropical Meteorology 2017年第3期23卷 334-344页

作者： ZHANG lei HUO Zhi-guo ZHANG Li-zhen HUANG Da-peng Chinese Academy of Meteorological Sciences Beijing 100081 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science ＆ Technology Nanjing 210044 China National Meteorological Center Beijing 100081 China China Agricultural University Beijing 100083 China National Climate Center Beijing 100081 China

Paprika pepper, as one of the main vegetable crops, is originated in the tropics and now widely planted in the world for its dietary therapy and medicinal functions. For its typical physiological properties referring to low tolerances to flood, drought and cold, paprika pepper often suffers from one or several disasters during its growing period,especially under tropical climate. Paprika pepper in Hainan, as a typical region of tropical climate in China, sustains flood, chilling and drought disaster risks induced by varied weather systems. This study was to develop and employ appropriate indices to assess hazard, sensitivity, vulnerability and prevention capability for major disasters during paprika pepper growth period, using long-term meteorological data from 1998 to 2011, actual disasters record from 1999 to 2011, production and socioeconomic statistics from 2002 to 2011 at 18 weather stations. Based on the Analytic Hierarchy Process and Entropy method, the combined weight was given to each disaster factor, thus an integrated disaster risk assessment model was developed and applied at regional level. High flood hazard mainly occurred in eastern Hainan, high chilling hazard in north and central mountain areas, and high drought hazard in the western part of Hainan. Drought and chilling sensitivity had a similar spatial distribution which decreased from central to coastal regions while flood sensitivity was the opposite. High vulnerability of the disasters mainly occurred in central regions,similar to low prevention capability. Eastern Hainan suffered from high integrated damage risk. The predicted damage occurrence showed a good agreement with the occurrence of actual disasters. We concluded that an integrated damage risk assessment model could provide a new tool to assess major meteorological disasters and help farmers and policy makers to alleviate the risks of major meteorological disasters for paprika pepper, which seems also suitable for other crops.

关键词： flood chilling drought integrated risk assessment paprika pepper

A Compositive Information Collection Platform System Based on Web Service

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 217-220页

作者： LIU zhen-peng NIU Xiao-xia XU Jian-min SHI lei XUE Yu-qian School of Management Tianjin University Tianjin 300072 China School of Mathematics and Computer Science Hebei University Baoding 071002 Hebei China

The aim is to solve the problem that how to share dispersive and heterogeneous data inside business information system or some other information source. On the basis of Web service, this paper adopts the notion of Data As ,Service to build service-oriented data integration architecture. According to this architecture, we develop data collection system which effectively integrates data from heterogeneous informa tion source and present a uniform data view to end users by implementing sharing data from heterogeneous systems and information source . At last, this paper gives an example of a compositive information collection platform system.

关键词： Web service information collection platform data integration

Probes of axial and nonaxial hexadecapole deformation effects in nuclei around^(230)U

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Communications in Theoretical Physics 2023年第2期75卷 133-143页

作者： Zhuo Song Hua-lei Wang zhen-zhen Zhang Min-Liang Liu School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

The structure properties for even–even nuclei around^(230)U,located on the hexadecapoledeformation island,are investigated using the potential-energy-surface calculation within the framework of the macroscopic-microscopic *** impact of different deformation degrees of freedom(including axial and nonaxial quadrupole and hexadecapole deformations)on total energy,shell,and pairing contributions is analyzed,based on the projected energy maps and *** single-particle structure is presented and briefly *** a large extent,a much better agreement with experimental data and other theoretical results is obtained if the hexadecapole deformations,especially the axial one,are taken into *** results could provide useful insights into understanding the effects of different quadrupole and hexadecapole deformations.

关键词： hexadecapole deformation triaxial deformation even-even nuclei potential-energysurface calculation macroscopic−microscopic model

Graphite dust resuspension in an HTR-10 steam generator

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Particuology 2014年第6期12卷 149-157页

作者： Wei peng Tianqi Zhang Yanan zhen Suyuan Yu Institute of Nuclear and New Energy Technology of Tsinghua University Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Center for Combustion Energy Key Laboratory for Thermal Science and Power Engineering of Ministry of EducationsDepartment of Thermal EngineeringTsinghua University

Graphite dust has an important effect on the safety of high-temperature gas-cooled reactors（HTR）.The flow field in the steam generator was studied by the computational fluid dynamics（CFD） method,with the results indicating that the friction velocity in the windward and the leeward of the heat transfer tubes is relatively low and is higher at the *** analysis of the resuspension of graphite dust indicates that the resuspension fraction reaches nearly zero for particles with a diameter less than 1 μm,whereas it will increases as the helium velocity in the steam generator increases for particle size larger than 1 μ***,the resuspension fraction increases as the particle size *** results also indicate that resuspension of the particles with sizes larger than 1 μm exhibited obvious differences in different parts of the steam generator.

关键词： Graphite dust High-temperature gas-cooled reactor(HTR) Steam generator Resuspension

A compact streamfunction-velocity scheme for the 2-D unsteady incompressible Navier-Stokes equations in arbitrary curvilinear coordinates

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Journal of Hydrodynamics 2019年第4期31卷 827-839页

作者： Jian-xin Qiu Bo peng zhen-fu Tian Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China

A streamfunction-velocity formulation-based compact difference method is suggested for solving the unsteady incompressible Navier-Stokes equations in the arbitrary curvilinear coordinates, in which the stream function and its first derivatives as the unknown variables are utilized. Numerical examples, involving the boundary layer problem, a constricted channel flow, driven polar cavity flow and trapezoidal cavity flow problem, are solved by the present method. Numerical results demonstrate the accuracy of the proposed scheme and exhibit the numerical capability to simulate the flow problems on geometries beyond rectangular. For driven polar cavity flow problem, the results show that the flow for Re = 5 000 is not steady but time-periodic, and the critical Reynold number (Rec) for the occurrence of a Hopf bifurcation is given.

关键词： Streamfunction-velocity formulation arbitrary curvilinear coordinates compact scheme unsteady incompressible flow

Influence of relative phase on the nonsequential double ionization process of CO_(2) molecules by counter-rotating two-color circularly polarized laser fields

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Communications in Theoretical Physics 2021年第7期73卷 121-126页

作者： Mian peng Li-Hua Bai zhen Guo Department of Physics College of SciencesShanghai UniversityShanghai 200444China

We investigate the nonsequential double ionization(NSDI) of linear triatomic molecules by the counter-rotating two-color circularly polarized(CRTC) laser fields with a classical ensemble method. The results of the simulation reveal that NSDI yield strongly connected with the relative phase. The trajectory tracking method shows that the return time of the electron is controlled by the relative phase. In addition, when we change the CRTC laser wavelengths, the relative phase of the maximum and minimum yield of NSDI also changes. This shows that the influence of the Coulomb potential in the triatomic molecules on the electron return process cannot be ignored. This work will effectively promote the electronic dynamics study of NSDI for the triatomic molecule.

关键词： linear triatomic molecules relative phase two-color laser fields nonsequential double ionization

Recent advances of allenes in the first-row transition metals catalyzed C-H activation reactions

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Chinese Chemical Letters 2019年第8期30卷 1495-1502页

作者： Xiang-lei Han peng-peng Lin Qingjiang Li School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100191China

Transition-metal-catalyzed C–H activation reaction has proven to be a powerful and efficient tool for the formation of diverse C-C and C–X bond and construction of functional complex *** the viewpoint of sustainable chemistry,the first-row transition metals,such as Mn,Fe,Co,Ni and Cu,have been recognized as cheap,environmentally friendly and reactively effective catalysts for a number of C-H functionalization ***,compared with the commonly used alkenes and alkynes in the first-row transition-metal-catalyzed C–H activations,considerable achievements have just been made by the use of structurally unique and reactively rich allenes as coupling partners in recent *** review summarizes the recent progress of the first-row transition-metal-catalyzed C–H activations with allenes.

关键词： Allene C-H functionalization First-row transition metal Annulation Regioselectivity

Graphite dust deposition in the HTR-10 steam generator

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Particuology 2013年第5期11卷 533-539页

作者： Wei peng Yanan zhen Xiaoyong Yang Suyuan Yu Institute of Nuclear and New Energy Technology of Tsinghua University The Key Laboratory of Advanced Reactor Engineering and SafetyMinistry of Education

Graphite dust has an important effect on the safe operation of a high-temperature gas-cooled reactor （HTR）. The present study analyzes temperature and flow field distributions in the HTR-10 steam genera- tor. The temperature and flow field distributions are then used to study thermophoretic deposition and turbulent deposition. The results show that as the dust diameter increases, the thermophoretic deposition decreases, while the turbulent deposition first decreases and then increases. The thermophoretic deposi- tion is higher at higher reactor powers, with turbulent deposition growing more rapidly at higher reactor power. For small particles, the thermophoretic deposition effect is greater than the turbulent deposition effect, while for large particles, the turbulent deposition effect is dominant.

关键词： Graphite dustHigh-temperature gas-cooled reactorSteam generatorDeposition

Denitrification potential enhancement by addition of external carbon sources in a pre-denitrification process

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Journal of Environmental Sciences 2007年第3期19卷 284-289页

作者： peng Yong-zhen MA Yong WANG Shu-ying School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering Beijing University of Technology Beijing 100022 China

The aim of this study is to investigate the denitrification potential enhancement by addition of external carbon sources and to estimate the denitrification potential for the predenitrification system using nitrate utilization rate （NUR） batch tests. It is shown that the denitrification potential can be substantially increased with the addition of three external carbon sources, i.e. methanol, ethanol, and acetate, and the denitrification rates of ethanol, acetate, and methanol reached up to 9.6, 12, and 3.2 mgN/（g VSS.h）, respectively, while that of starch wastewater was only 0.74 mgN/（g VSS,h）. By comparison, ethanol was found to be the best external carbon source. NUR batch tests with starch wastewater and waste ethanol were carried out. The denitfification potential increased from 5.6 to 16.5 mg NO3-N/L owing to waste ethanol addition. By means of NUR tests, the wastewater characteristics and kinetic parameters can be estimated, which are used to determine the denitrification potential of wastewater, to calculate the denitrification potential of the plant and to predict the nitrate effluent quality, as well as provide information for developing carbon dosage control strategy.

关键词： predenitrification process external carbon addition ethanol denitrification potential