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Precipitation Distribution of the Extended Global Spring-Autumn Monsoon and Its Possible Formation Mechanism

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Journal of Ocean University of China 2021年第5期20卷 1027-1036页

作者： QIN ling huang Fei XU Shibin Key Laboratory of Physical Oceanography Ocean University of ChinaQingdao 266100China Laboratory for Ocean and Climate Dynamics Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266100China Ningbo Collaborative Innovation Center of Nonlinear Hazard System of Ocean and Atmosphere Ningbo UniversityNingbo 315211China

The global monsoon(GM)comprises two major modes,namely,the solstitial mode and equinoctial asymmetric *** this paper,we extend the GM domain from the tropics to the global region and name it the global spring-autumn monsoon(GSAM),which mainly indicates a spring-autumn asymmetrical precipitation pattern exhibiting annual *** distribution and possible formation mechanisms are also *** GSAM domain is mainly distributed over oceans,located both in the midlatitude and tropical regions of the Pacific and *** the GSAM domains of both the Northern and Southern Hemispheres,more precipitation occurs in local autumn than in local *** formation mechanisms of GSAM precipitation vary according to the different *** precipitation in the tropical domain of the Eastern Hemisphere is influenced by the circulation differences between the onset and retreat periods of the Asian summer monsoon,while tropical cyclone activities cause precipitation over the South China Sea(SCS)and western North Pacific(WNP).GSAM precipitation in the tropical domain of the Western Hemisphere is influenced by the tropical asymmetrical circulation between the Northern and Southern Hemispheres and the variation in the intertropical convergence zone(ITCZ)driven by the intensity of the sea surface temperature cold tongues over the equatorial eastern Pacific and eastern *** precipitation in the midlatitude domain is influenced by the differences in water vapor transportation and convergence between spring and *** addition,GSAM precipitation is also affected by extratropical cyclone activities.

关键词： global monsoon equinoctial asymmetric mode monsoon precipitation mechanism

A voltammetric sensor for simultaneous determination of lead,cadmium and zinc on an activated carbon fiber rod

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Chinese Chemical Letters 2018年第1期29卷 111-114页

作者： Wei-Jie Wang Yan-ling Cai Bai-Chuan Li Jun Zeng Zhi-Yong huang Xiao-mei Chen College of Food and Biological Engineering Jimei University

In this work, a simple, low cost and sensitive voltammetric sensor was developed for the simultaneous detection of lead （Pb2＋）, cadmium （Cd2＋）, and zinc （Zn2＋） ions based on a disposable carbon fiber rod （CFR）. The important factors to enhance the sensing property were creation of a clean surface by dealing with CFR at a high potential and electrochemical deposition of bismuth （Bi） film to improve the accumulation of heavy metal ions. The morphology and conductivity of such activated CFR was characterized by scanning electron microscopy and electrochemical impedance spectroscopy, respectively. In terms of application, differential pulse anodic stripping voltammetry （DPASV） was employed for the simultaneous detection of Pb2＋, Cd2＋, and Zn2＋ on Bi film-coated activated CFR. Experimental parameters, such as the pH value of buffer solution, stirring speed and enrichment factors were optimized. Under optimal conditions, the DPASV peak currents showed good linear relationships with Pb2＋, Cd2＋ and Zn2＋ concentrations in the range of 0.5-2.25 μg/L, 0.5-4.0 μg/L and 1.0- 4.0 μg/L with detection limits of 0.1, 0.3 and 1.0 μg/L （SIN = 3）, respectively. Finally, the proposed analysis system was successfully utilized for the simultaneous detection of Pb2＋, Cd2＋, and Zn2＋ contents in rice samples. This study indicated that Bi film-coated activated CFR based DPASV sensor can be a promising and reliable tool for rapid analysis of emergency Dollution affairs of heavv metal ions in food.

关键词： Carbon fiber rodBismuth filmDifferential pulse anodic stripping voltammetryHeavy metal ionsSensor

NUMERICAL BOUNDARY CONDITIONS FOR THE FAST SWEEPING HIGH ORDER WENO METHODS FOR SOLVING THE EIKONAL EQUATION

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Journal of Computational Mathematics 2008年第3期26卷 336-346页

作者： ling huang Chi-Wang Shu Mengping Zhang Department of Mathematics University of Science and Technology of China Hefei Anhui 230026 China Division of Applied Mathematics Brown University Providence RI 02912 USA Department of Mathematics University of Science and Technology of China Hefei 230026 China

High order fast sweeping methods have been developed recently in the literature to solve static Hamilton-Jacobi equations efficiently. Comparing with the first order fast sweeping methods, the high order fast sweeping methods are more accurate, but they often require additional numerical boundary treatment for several grid points near the boundary because of the wider numerical stencil. It is particularly important to treat the points near the inflow boundary accurately, as the information would flow into the computational domain and would affect global accuracy. In the literature, the numerical solution at these boundary points are either fixed with the exact solution, which is not always feasible, or computed with a first order discretization, which could reduce the global accuracy. In this paper, we discuss two strategies to handle the inflow boundary conditions. One is based on the numerical solutions of a first order fast sweeping method with several different mesh sizes near the boundary and a Richardson extrapolation, the other is based on a Lax-Wendroff type procedure to repeatedly utilizing the PDE to write the normal spatial derivatives to the inflow boundary in terms of the tangential derivatives, thereby obtaining high order solution values at the grid points near the inflow boundary. We explore these two approaches using the fast sweeping high order WENO scheme in [18] for solving the static Eikonal equation as a representative example. Numerical examples are given to demonstrate the performance of these two approaches.

关键词： Fast sweeping method WENO scheme Boundary condition

Numerical investigation of filling transients in small-scale pipelines with submerged outlet

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Journal of Hydrodynamics 2019年第1期31卷 145-151页

作者： ling Wang Fu-jun Wang Jing huang College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing 100083China Zhuzhou Southern Valve Co. Ltd Zhuzhou 412007China

An elastic model that combines the dead-end and the orifice at the downstream end is proposed in order to study the hydraulic transients during the rapid filling in small-scale pipelines with submerged *** this model,the unsteady water flow is solved by the method of characteristics,the water-air interface is traced by a shock fitting method,and the air phase is controlled by the polytropic *** model is validated by a filling test in a pipeline with *** the proposed model is applied to the filling transient analysis in a small-scale pipeline with submerged ***,the effects of the submerged depth of the downstream reservoir on the filling transients are *** model provides a reasonable approximation of the submerged outlet boundary condition in small-scale pipelines.

关键词： Small-scale pipelines rapid filling submerged outlet elastic model hydraulic transients

Maximum two-dimensional (u×v,4,1,3)-OOCs

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Applied Mathematics(A Journal of Chinese Universities) 2013年第3期28卷 279-289页

作者： huang Yue-mei CHANG Yan-xun Institute of Mathematics Beijing Jiaotong University Mathematics Science college Inner Mongolia Normal University

Let Ф（u ×v, k, Aa, Ac） be the largest possible number of codewords among all two- dimensional （u ×v, k, λa, λc） optical orthogonal codes. A 2-D （u× v, k, λa, λ）-OOC with Ф（u× v, k, λa, λc） codewords is said to be maximum. In this paper, the number of codewords of a maximum 2-D （u × v, 4, 1, 3）-OOC has been determined.

关键词： maximum two-dimensional optical orthogonal code orbit.

Theoretical Studies on the Intermonomer Interaction of F^(-)·(H_(2)O)_(n)(n=1,2)

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Chinese Journal of Structural Chemistry 2005年第5期24卷 561-567,491页

作者： WANG Yong-Cheng Lüling-ling GENG Zhi-Yuan DAI Guo-Liang WANG Dong-mei Department of Chemistry Northwest Normal UniversityLanzhou 730070China Department of Chemistry Tianshui Normal UniversityGansu 741009China

Five optimized geometries of F-?(H2O)n (n = 1, 2) were obtained with ab initio calculation at the B3LYP/6-311++G** level. The accurate intermonomer interaction energy was calculated using the MP2 electron correlation correction as well as the basis set superposition error correction by the Boys-Bernardi “counterpoise” protocol. Natural bond orbital (NBO) theory was applied to quantify the relative strength of these interactions and account for their effects on the stability, structural and vibrational parameters of Fˉ?(H2O)n (n = 1, 2). It is shown that the charge transferring from the lone pair of F-1 to the σ?OH(…F) antibonding orbital is important. The results indicate the occupancy of σ?OH(…F) is increased (denoted ?σ?OH(…F)) and the σOH(…F) bond is leng- thened (denoted ?ROH(…F)), leading to the red-shift and the red-shift values have linear correlation with both ?σ?OH(…F) and ?ROH(…F).

关键词： F^(-)·(H_(2)O)_(n)(n=1,2) interaction energy red-shift linear correlation

Prediction of carbon exchanges between China terrestrial ecosystem and atmosphere in 21st century

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Science China Earth Sciences 2008年第6期51卷 885-898页

作者： JI JinJun huang mei LI KeRang Chinese Ecosystem Research Network Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

The projected changes in carbon exchange between China terrestrial ecosystem and the atmosphere and vegetation and soil carbon storage during the 21st century were investigated using an atmos-phere-vegetation interaction model (AVIM2). The results show that in the coming 100 a, for SRES B2 scenario and constant atmospheric CO2 concentration, the net primary productivity (NPP) of terrestrial ecosystem in China will be decreased slowly, and vegetation and soil carbon storage as well as net ecosystem productivity (NEP) will also be decreased. The carbon sink for China terrestrial ecosystem in the beginning of the 20th century will become totally a carbon source by the year of 2020, while for B2 scenario and changing atmospheric CO2 concentration, NPP for China will increase continuously from 2.94 GtC·a?1 by the end of the 20th century to 3.99 GtC·a?1 by the end of the 21st century, and vegetation and soil carbon storage will increase to 110.3 GtC. NEP in China will keep rising during the first and middle periods of the 21st century, and reach the peak around 2050s, then will decrease gradually and approach to zero by the end of the 21st century.

关键词： carbon cycle AVIM2 climate change B2 scenario China terrestrial ecosystems

High-Speed EMU TCMS Design and LCC Technology Research

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Engineering 2017年第1期3卷 122-129页

作者： Hongwei Zhao Zhiping huang Ying mei China Academy of Railway Sciences Beijing 100081 China Beijing Zongheng Electro-Mechanical Technology Development Co. Beijing 100094 China

This paper introduces the high-speed electrical multiple unit （EMO） life cycle, including the design, manufacturing, testing, and maintenance stages. It also presents the train control and monitoring system （TCMS） software development platform, the TCMS testing and verification bench, the EMU driving simulation platform, and the EMU remote data transmittal and maintenance platform. All these platforms and benches combined together make up the EMU life cycle cost （LCC） system. Each platform facilitates EMU LCC management and is an important part of the system.

关键词： Electrical multiple unit Train control and monitoring system Train communication network Life cycle cost Development platform Testing bench Simulation Remote data transmittal

Colour modulation and enhancement of upconversion emissions in K_(2)NaScF_(6):Yb/Ln(Ln=Er,Ho,Tm) nanocrystals

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Journal of Rare Earths 2021年第12期39卷 1477-1483,I0001页

作者： Yangbo Wang Huaiyong Li Hui Ma ling huang School of Materials Science and Engineering Liaocheng UniversityLiaocheng 252059China Institute of Advanced Materials Nanjing Tech UniversityNanjing 211816China

Effective colour modulation of upconversion emissions in lanthanide-doped nanomaterials becomes even more important for fundamental and applied ***,on the one hand,by raising the content of doped Yb^(3+)from 10 mol%to 50 mol%,a significant increase of the red/green emission ratio from 4.0 to 68.2 is observed in K_(2)NaScF_(6):Yb/Er *** yellow to red colour change is attributed to the increased cross relaxation between Er^(3+)and Yb^(3+)caused by the increased Yb^(3+)amount,^(4) S_(3/2)(Er^(3+))^(+2) F7/2(Yb^(3+))→4 I13/2(Er^(3+))^(+2) F5/2(Yb^(3+)).On the other hand,the upconversion green and red emission of K_(2)NaScF_(6):Yb/Er(20/2 mol%)nanocrystals are intensified 10.6 and 8.8 folds,respectively,after an active shell(K_(2)NaScF_(6):Yb)is epitaxially grown,which are more effective than the7.4-and 6.4-fold enhancement from an inert shell(K_(2)NaScF_(6))***,the shell thickness from2.85 to 9.5 nm through controlling the molar ratio of shell-precursor to core from 1:2 to 3:1 can be easily *** study will provide more opportunities for the application of K_(2)NaScF_(6):Yb/Ln nanoparticles in varied fields such as theranostics,photovoltaics,and photocatalysis.

关键词： Upconversion Emission modulation Core-shell K_(2)NaScF_(6) Rare earths