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Analysis on Relationship between Overcast and Rainy Weather, Drought, Flood and Wheat Yield

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Meteorological and Environmental Research 2011年第9期2卷 47-48,80页

作者： YU Li-jie wang xiu-fang LIU Jing-jing Jiyuan Meteorological Bureau in Henan Province Jiyuan 459000China Anyang Meteorological Bureau in Henan Province Anyang 455000China

[Objective] The research aimed to study influence of meteorological factor in late growth stage of wheat. [Method] Based on precipitation, sunshine and yield per unit of wheat in Anyang City in May of 1979-2008, the positive and negative influences of meteorological condition in late growth stage of wheat (May) on wheat yield in Anyang City were analyzed by using agricultural climatic statistical method. Moreover, the reason and defense measure of green-dry hazard in late growth stage of wheat in the city were studied. [Result] When the sunshine percentage in May > 55%, and rainfall 80 mm, and monthly sunshine percentage < 55%, the wheat yield generally reduced. The overcast and rainy weather, flood in late growth stage of wheat were easy to cause green-dry yield reduction. The rainless weather even drought weren’t obviously unfavorable for good harvest of wheat. In May, when precipitation was too more, or duration was too long, and the air humidity was too big, the normal water supply and inorganic nutrient transmission were affected. Meanwhile, when the overcast and rainy weather was longer, the sunshine was shorter, and the sunshine intensity weakened in late stage, it wasn’t favorable for accumulation of photosynthetic product, and the normal implementing of grouting process was affected. The measures should be used to prevent and control green-dry yield reduction of wheat, such as discharging water and preventing flood, breeding good seed, scientific planting and reasonable irrigation. [Conclusion] The research provided scientific basis for studying variety improvement, scientific plantation, reasonable irrigation, good quality and high yield of wheat.

关键词： Wheat yield Meteorological factor Late growth stage Influence analysis China

A bifunctional POM-based Cu-viologen complex with mixed octamolybdate clusters for rapid oxidation desulfurization and effective photogeneration of hydrogen

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Rare Metals 2024年第1期43卷 236-246页

作者： Lin Yang Zhong Zhang Chao-Nan Zhang xiu-Li wang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar Cell Bohai UniversityJinzhou 121013China

The design and synthesis of catalysts for the oxidation desulfurization and production of hydrogen are extremely important for solving environmental pollution and energy ***,a novel bifunctional [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)-based Cu-viologen complex H_(4)[Cu_(2)~ⅠCl_(2)(Hbcbpy)_(4)] [α-Mo_(8)O_(26)] [β-Mo8O_(26)]·H_(2)O(BHU-2,Hbcbpy=1-(4-carboxybenzyl)-4,4'-bipyridinium) was synthesized and characterized by single-crystal X-ray diffraction(XRD),infrared radiation spectra,powder X-ray diffraction(PXRD) and X-ray photoelectron spectroscopy(XPS) *** structural characteristic of BHU-2 is the presence of two types of octamolybdate clusters [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)and a new binuclear Cu~Ⅰ-Hbcbpy complex linked by Cl-bridges[Cu_(2)ⅠCl_(2)(Hbcbpy)_(4)]^(4+).BHU-2 as a heterogeneous catalyst exhibits excellent activities to the oxidation desulfurization and photocatalytic hydrogen *** room temperature,BHU-2 can catalyze 96% conversion of methyl phenyl sulfide with 98% selectivity,and the process obeys the pseudo-first-order reaction kinetic with the half-life of9.6 *** notorious 2-chloroethyl ethyl sulfide can achieve 99% conversion with 98% selectivity within only1 min at the presence of BHU-2,and the turnover frequency(TOF) is up to 7400 h^(-1).BHU-2 also exhibits high catalytic activity for the oxidation of other aromatic and aliphatic thioethers within short time at room ***,BHU-2 shows a high catalytic activity for visible-light-driven hydrogen evolution with an H_(2) evolution rate of 1677.85 μmol·g^(-1)·h^(-1) within 10 ***,the catalytic activities do not decrease evidently after three cycles,revealing the prominent structural stability and recyclability.

关键词： Polyoxometalate Metal-organic complex Viologen Oxidation desulfurization Photocatalytic hydrogen production

On the superconvergence of a WG method for the elliptic problem with variable coefficients

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Science China Mathematics 2024年第8期67卷 1899-1910页

作者： Junping wang Xiaoshen wang xiu Ye Shangyou Zhang Peng Zhu Division of Mathematical Sciences National Science FoundationAlexandriaVA 22314USA Department of Mathematics University of Arkansas at Little RockLittle RockAR 72204USA Department of Mathematical Sciences University of DelawareNewarkDE 19716USA College of Data Science Jiaxing UniversityJiaxing 314001China

This article extends a recently developed superconvergence result for weak Galerkin(WG)approximations for modeling partial differential equations from constant coefficients to variable *** superconvergence features a rate that is two orders higher than the optimal-order error estimates in the usual energy and L^(2)*** extension from constant to variable coefficients for the modeling equations is highly *** underlying technical analysis is based on a sequence of projections and *** results confirm the superconvergence theory for second-order elliptic problems with variable coefficients.

关键词： weak Galerkin finite element methods superconvergence second-order elliptic problems stabilizerfree

A novel triple periodic minimal surface-like plate lattice and its data-driven optimization method for superior mechanical properties

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 217-238页

作者： Yanda wang Yanping LIAN Zhidong wang Chunpeng wang Daining fang State Key Laboratory for Turbulence and Complex Systems&Center for Applied Physics and Technology College of EngineeringPeking UniversityBeijing 100871China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

Lattice structures can be designed to achieve unique mechanical properties and have attracted increasing attention for applications in high-end industrial equipment,along with the advances in additive manufacturing(AM)*** this work,a novel design of plate lattice structures described by a parametric model is proposed to enrich the design space of plate lattice structures with high connectivity suitable for AM *** parametric model takes the basic unit of the triple periodic minimal surface(TPMS)lattice as a skeleton and adopts a set of generation parameters to determine the plate lattice structure with different topologies,which takes the advantages of both plate lattices for superior specific mechanical properties and TPMS lattices for high connectivity,and therefore is referred to as a TPMS-like plate lattice(TLPL).Furthermore,a data-driven shape optimization method is proposed to optimize the TLPL structure for maximum mechanical properties with or without the isotropic *** this method,the genetic algorithm for the optimization is utilized for global search capability,and an artificial neural network(ANN)model for individual fitness estimation is integrated for high efficiency.A set of optimized TLPLs at different relative densities are experimentally validated by the selective laser melting(SLM)fabricated *** is confirmed that the optimized TLPLs could achieve elastic isotropy and have superior stiffness over other isotropic lattice structures.

关键词： lattice structure triple periodic minimal surface(TPMS) plate lattice structural optimization machine learning

Hypoglycemic effect and the mechanism of action of a polysaccharide from sweet corncob in a high-fat diet and streptozotocin-induced diabetic mice

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Food Science and Human Wellness 2024年第3期13卷 1543-1555页

作者： Xin wang Weiye xiu Ye Han Zhili wang Yu Luo Yongqiang Ma Heilongjiang Provincial Key Laboratory of Cereals and Comprehensive Processing of Cereal Resources College of Food EngineeringHarbin University of CommerceHarbin 150028China

Type 2 diabetes mellitus(T2DM)is a metabolic disease caused by a glycolipid metabolism disorder and isletβ-cell ***-80-I is a biologically active water-soluble polysaccharide isolated from sweet corncob,an agricultural *** hypoglycemic effects of SCP-80-I on T2DM mice and its mechanisms were investigated in this ***-80-I was found to significantly reduce blood glucose and lipid deposition levels in T2DM mice,as well as decrease serum leptin and increase adiponectin ***,real time-polymerase chain reaction(RT-PCR)and Western blotting results revealed that SCP-80-I could regulate the expression of several glycolipid metabolisms and insulin secretion genes and proteins,including 5'-AMP-activated protein kinase(AMPK),carnitine palmitoyltransferase I(CPTI),and acetyl coenzyme A carboxylase(ACC)in the liver and AMPK,sirtuin1(Sirtl),peroxisome proliferator-activated receptorycoactivator-1(PGC-1α),and uncoupling protein 2(UCP2)in the *** have a hypoglycemic effect,SCP-80-1 regulated glycolipid metabolism and islet cell function in the liver by regulating the AMPK/AC C/CPT1 signaling pathway and the AMPK/Sirt1/PGC-1αand AMPK/Sirtl/UCP2 signaling *** findings improve our understanding of polysaccharides derived from sweet corncob and the use of SCP-80-I in the production of hypoglycemic foods.

关键词： Sweet corn cob polysaccharide Type 2 diabetes Signal pathway 5’-AMP-activated protein kinase(AMPK)

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地形图点状符号的自动提取和识别

自动化学报 2007年第10期33卷 1074-1080页

作者：陈飞王秀芳王坤农宇武汉大学资源与环境科学学院武汉430079 武汉大学遥感信息与工程学院武汉430079

针对扫描地形图的点状符号,提出了一种基于距离变换进行提取和识别的新方法.首先优化分版图的提取结果,根据弯曲密度和线划密度过滤掉非点状符号的线划,利用加壳变换和蜕皮变换进行点状符号的图文分离.然后根据加权距离函数来度量符号... 详细信息

针对扫描地形图的点状符号,提出了一种基于距离变换进行提取和识别的新方法.首先优化分版图的提取结果,根据弯曲密度和线划密度过滤掉非点状符号的线划,利用加壳变换和蜕皮变换进行点状符号的图文分离.然后根据加权距离函数来度量符号的全局特征,由骨架线的一致性米度量符号的几何形状特征,并结合这两个特征来识别点状符号.最后,提出了错切文字注记和线状要素注记的识别方法.

关键词：地形图点状符号距离变换线划弯曲度符号骨架线

A disk I/O optimized system for concurrent graph processing jobs

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Frontiers of Computer Science 2024年第3期18卷 13-29页

作者： Xianghao XU fang wang Hong JIANG Yongli CHENG Dan FENG Peng fang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Department of Computer Science&Engineering University of Texas at ArlingtonArlingtonTX 76019USA College of Computer and Data Science Fuzhou UniversityFuzhou 350108China Zhejiang Lab Hangzhou 311121China

In order to analyze and process the large graphs with high cost efficiency,researchers have developed a number of out-of-core graph processing systems in recent years based on just one commodity *** the other hand,with the rapidly growing need of analyzing graphs in the real-world,graph processing systems have to efficiently handle massive concurrent graph processing(CGP)***,due to the inherent design for single graph processing job,existing out-of-core graph processing systems usually incur unnecessary data accesses and severe competition of I/O bandwidth when handling the CGP *** this paper,we propose GraphCP,a disk I/O optimized out-of-core graph processing system that efficiently supports the processing of CGP *** proposes a benefit-aware sharing execution model to share the I/O access and processing of graph data among the CGP jobs and adaptively schedule the graph data loading based on the states of vertices,which efficiently overcomes above challenges faced by existing out-of-core graph processing ***,GraphCP adopts a dependency-based future-vertex updating model so as to reduce disk I/Os in the future *** addition,GraphCP organizes the graph data with a Source-Sorted Sub-Block graph representation for better processing capacity and I/O access *** evaluation results show that GraphCP is 20.5×and 8.9×faster than two out-of-core graph processing systems GridGraph and GraphZ,and 3.5×and 1.7×faster than two state-of-art concurrent graph processing systems Seraph and GraphSO.

关键词： graph processing disk I/O concurrent jobs

Thermo-hydro-mechanical (THM) coupled simulation of the land subsidence due to aquifer thermal energy storage (ATES) system in soft soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1952-1966页

作者： Yang wang Fengshou Zhang fang Liu Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai200092China Shanghai Engineering and Technology Research Center of Shallow Geothermal Energy Shanghai200072China

Aquifer thermal energy storage(ATES)system has received attention for heating or cooling ***,it is well known that land subsidence becomes a major environmental concern for ATES ***,the effect of temperature on land subsidence has received practically no attention in the *** paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,*** water wells were installed for seasonal heating and cooling of an agriculture *** target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with *** level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring *** by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive *** effectiveness of the numerical model was validated by field *** model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land *** results show that the maximum thermoinduced land subsidence accounts for about 60%of the total *** thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well *** study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils.

关键词： Aquifer thermal energy storage(ATES) Land subsidence TOUGH-FLAC3D Thermo-elastoplastic constitutive model

Unusual Single Electron Transfer Reactions between Alkenes and Iodine Electrophiles

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Chinese Journal of Chemistry 2024年第5期42卷 471-477页

作者： Zhengzhao Lou Jingyu Hu Chuanfa Ni xiu wang Jinbo Hu Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Ling Ling RoadShanghai200032 China School of Physical Science and Technology ShanghaiTech University100 Haike RoadShanghai201210 China

The electrophilic addition to an alkene with an electrophile has been widely studied and applied in organic *** organic chemistry textbook describes the classical reaction between an alkene and an iodine electrophile(such as elemental iodine and N-iodosuccinimide(NIS))as a typical ionic reaction,in which an iodonium ion is formed and then attacked by a ***,in this article,we report a new and unusual reaction mode between an alkene and NIS;that is,a single electron transfer(SET)process occurs between these two reactants by forming an electron-donor acceptor *** only does this unusual single electron transfer reaction between an alkene and NIS add fundamentally important knowledge to organic chemistry,it also provides a valuable synthetic method as the new SET reaction mode with opposite regioselectivity as compared with the traditional ionic mode.

关键词： Electrophilic addition Radical ions Reaction mechanisms Alkenes Fluorine