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Local Well-posedness for Linearized Degenerate MHD Boundary Layer Equations in Analytic Setting

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Acta Mathematica Sinica,English Series 2019年第8期35卷 1402-1418页

作者： ya Jun LI Wen Dong wang School of Mathematical Sciences Dalian University of Technology

In this note we derive MHD boundary layer equations according to viscosity and resistivity coefficients. Especially, when these viscosity and resistivity coefficients are of different orders, it leads to degenerate MH... 详细信息

关键词： MHD equations degenerate boundary layer equations local well-posedness analytic spaces

Interdecadal Variations of the South Asian Summer Monsoon Circulation Variability and the Associated Sea Surface Temperatures on Interannual Scales

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Advances in Atmospheric Sciences 2017年第7期34卷 816-832页

作者： ya GAO Huijun wang Dong CHEN Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Key Laboratory of Meteorological Disaster/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology

We investigate the interannual variability of the South Asian summer monsoon（SASM） circulation, which has experienced a significant interdecadal change since 2000. This change is primarily influenced by sea surface temperatures（SSTs）in the tropical Pacific and North Atlantic oceans. During the pre-2000 period examined in this study（1979-99）, the SASM is negatively correlated with eastern Pacific SSTs（the canonical ENSO mode） and positively correlated with the negative phase of the North Atlantic SST tripole（NAT）. During the post-2000 period（2000-14）, the SASM is negatively correlated with central Pacific SSTs and positively correlated with the positive phase of the NAT pattern. The associated Pacific SSTs change from the eastern to central region, leading to the rising（subsiding） branch of the Walker circulation moving westwards to the Maritime Continent in the latter period, which can impact the interannual variability of the SASM through modulating the wind field in the troposphere. In addition to Pacific SSTs, the NAT SSTs can propagate energy from the North Atlantic to the South Asian High（SAH） region through the wave activity flux, and then further impact the SASM via the *** the SASM is intimately related with precipitation over the Asian region, we briefly discuss the features of the precipitation patterns associated with the SASM during the two periods. The westward shifting Walker circulation leads to the shrinking and weakened anomalous westerlies of the SASM in the lower level, inducing the Maritime Continent rainfall location to move westwards and more moisture to arrive in southern China from the Pacific Ocean in the latter period.

关键词： interannual Atlantic ENSO anomalous equatorial tropical monsoon troposphere experienced eastern

A Method for Rapidly Determining the Optimal Distribution Locations of GNSS Stations for Orbit and ERP Measurement Based on Map Grid Zooming and Genetic Algorithm

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Computer Modeling in Engineering & Sciences 2018年第12期117卷 509-525页

作者： Qianxin wang Chao Hu ya Mao NASG Key Laboratory of Land Environment and Disaster Monitoring China University of Mining and TechnologyXuzhou221116China School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou221116China Mathematical and Geospatial Sciences RMIT UniversityMelbourne 3001Australia.

Designing the optimal distribution of Global Navigation Satellite System(GNSS)ground stations is crucial for determining the satellite orbit,satellite clock and Earth Rotation Parameters(ERP)at a desired precision using a limited number of *** this work,a new criterion for the optimal GNSS station distribution for orbit and ERP determination is proposed,named the minimum Orbit and ERP Dilution of Precision Factor(OEDOP)*** quickly identify the specific station locations for the optimal station distribution on a map,a method for the rapid determination of the selected station locations is developed,which is based on the map grid zooming and heuristic *** the minimum OEDOP criterion and the proposed method for the rapid determination of optimal station locations,an optimal or near-optimal station distribution scheme for 17 newly built BeiDou Navigation Satellite System(BDS)global tracking stations is *** verify the proposed criterion and method,real GNSS data are *** results show that the minimum OEDOP criterion is valid,as the smaller the value of OEDOP,the better the precision of the satellite orbit and ERP *** to the exhaustive method,the proposed method significantly improves the computational efficiency of the optimal station location *** the case of 3 newly built stations,the computational efficiency of the proposed method is 35 times greater than that of the exhaustive *** the number of stations increases,the improvement in the computational efficiency becomes increasingly obvious.

关键词： Global Navigation Satellite System(GNSS) optimal distribution of station network map grid zooming genetic algorithm.

Cloud point extraction coupled with HPLC-UV for the determination of phthalate esters in environmental water samples

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Journal of Environmental Sciences 2007年第7期19卷 874-878页

作者： wang Ling JIANG Gui-bin CAI ya-qi HE Bin wang ya-wei SHEN Da-zhong School of Chemistry and Chemical Engineering Shah Dong University Jinan 250100 China. State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Scienees Beijing 100085 China

A method based on cloud point extraction was developed to determine phthalate esters including di-ethyl-phthalate （DEP）, di- （2-ethylhexyl）-phthalate （DEHP） and di-cyclohexyl-phthalate （DCP） in environmental water samples using high-performance liquid chromatography separation and ultraviolet detection （HPLC-UV）. The non-ionic surfactant Triton X-114 was chosen as extraction solvent. The parameters affecting extraction efficiency, such as concentrations of Triton X-114 and Na2SO4, equilibration temperature, equilibration time and centrifugation time were evaluated and optimized. Under the optimum conditions, the method can achieve preconcentration factors of 35, 88, 111 and detection of limits of 2.0, 3.8, 1.0 ng/ml for DEP, DEHP and DCP in 10-ml water sample, respectively. The proposed method was successfully applied to the determination of trace amount of phathalate esters in effluent water of the wastewater treatment plant and the lixivium of plastic fragments.

关键词： phthalate esters cloud point extraction Triton X-114 non-ionic surfactant, HPLC-UV

Simulating Alpine Vegetation Net Primary Productivity by Remote Sensing in Qinghai Province,China

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Journal of Mountain Science 2014年第4期11卷 967-978页

作者： WEI ya-xing wang Li-wen Center for Marine Economic and Sustainable Development Liaoning Normal University Liaoning Key Laboratory of Physical Geography and Geomatics Liaoning Normal University College of Urban and Environmental Science Liaoning Normal University

Primary productivity of ecosystem is important indicator about ecological assessment. Remote sensing technology has been used to monitor net primary productivity （NPP） of ecological system for several years. In this paper, the remotely sensed NPP simulation model of alpine vegetation in Qinghai Province of Tibet Plateau was set up based on the theory of light use efficiency. Firstly a new approach based on mixed pixels and Support Vector Machine （SVM） algorithm were used to correct simulated NPP values derived from Moderate Resolution Imaging Spectroradiometer （MODIS） data. Finally, spatial distribution and monthly variation characteristics of NPP in Qinghai Province detail. The result showed in 2006 were analyzed in that NPP of vegetation in Qinghai Province in 2006 ranged from o to 422 gC/m2/a and the average NPP was 151 gC/m2/a. NPP gradually increased from northwest to southeast. NPP of different vegetation types were obviously different. The average NPP of broad-leaved forest was the largest （314 gC/m2/a）, and sparse shrub was the smallest （101 gC/m2/a）. NPP in Qinghai Province significantly changed with seasonal variation. The accumulation of NPP was primarily in the period （from April to September） with better moist and heat conditions. In July, the average NPP of vegetation reached the maximum value （43 gC/m2）. In our model, the advantage of traditional LUE models was adopted, and our study fully considered typicalcharacteristics of alpine vegetation light use efficiency and environmental factors in the study area. Alpine vegetation is the most important ecological resource of Tibet Plateau, exactly monitoring its NPP value by remote sensing is an effective protection measure.

关键词： Net primary productivity Remotesensing Light use efficiency model Contexturalapproach Support Vector Machine

The effect of drug position on the properties of paclitaxel-conjugated gold nanoparticles for liver tumor treatment

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Chinese Chemical Letters 2021年第3期32卷 1041-1045页

作者： Huaisong wang Lin wang Yueyuan Gao ya Ding Key Laboratory of Drug Quality Control and Pharmacovigilance Ministry of EducationChina Pharmaceutical UniversityNanjing 210009China

Structure-efficacy effect of small molecular drug attracts wide attentions,but it has always been ignored in nanomedicine *** reveal the efficacy modulation of nanomedicine,we developed a new type of paclitaxel(PTX)-conjugated gold nanoparticles(PTX-co njugated GNPs)to investigate the influence of drug position in controlling their in vitro properties and in vivo *** therapeutic ligands(TA-PEG-NH-N=PTX and TA-PTX=N-NH-PEG)were synthesized to conjugate PTX on the surface of GNPs at different positions,locating on the surface of gold conjugate and inserting between GNPs and polyethylene glycol(PEG,molecular weight 1000 Da),*** was found that PEG-PTX@GNPs with PTX located between GNP and PEG exhibited higher aqueous solubility,biocompatibility,and *** addition,an acid sensitive hydrazone bond has been inserted between PTX and PEG in both ligands for drug release of PTX and PTX-PEG segment,respectively,at the tumor *** release of PTX from PTX-PEG segment is based on the esterase hydrolysis of an ester bond between PTX and *** two-step drug release mechanism offers PEG-PTX@GNPs effective and sustained release behavior for desirable anticancer activity,enhanced therapeutic efficacy,and lower systematic toxicity in Hepsbearing animal models.

关键词： Gold nanoparticles Paclitaxel Drug release Tumor therapeutic efficacy Effect of drug position

Linear Biseparating Maps between Vector-valued Little Lipschitz Function Spaces

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Acta Mathematica Sinica,English Series 2010年第6期26卷 1005-1018页

作者： A. JIMENEZ-VARGAS ya-Shu wang Departamento de Algebra y Andlisis Matemdtico Universidad de Almerla 04120 Almerla Spain Department of Applied Mathematics National Sun Yet-Sen University 804 Kaohsinug Taiwan

In this paper we provide a complete description of linear biseparating maps between spaces lip0（X^a, E） of Banach-valued little Lipschitz functions vanishing at infinity on locally com-pact HSlder metric spaces X^a=（X,dx^a） with 0〈a〈***, it is proved that any linear bijection T ： lip0（X^a,E）→lip0（Y^a,F）satisfying that ｜｜Tf（y）｜｜F｜｜Tg（y）｜｜F= 0 for all y ∈ Y if and only if ｜｜f（x）｜｜E｜｜g（x）｜｜E=0 for all x E X, is a weighted composition operator of the form Tf（y） = h（y）（f（φ（y）））, where φ is a homeomorphism from Y onto X and h is a map from Y into the set of all linear bijections from E onto F. Moreover, T is continuous if and only if h（y） is continuous for all y ∈ Y. In this case, φ becomes a locally Lipschitz homeomorphism and h a locally Lipschitz map from Y^a into the space of all continuous linear bijections from E onto F with the metric induced by the operator canonical norm. This enables us to study the automatic continuity of T and the existence of discontinuous linear biseparating maps.

关键词： linear biseparating map little Lipschitz function Banach-Stone theorem automatic continuity

Busemann–Petty Problems for General L_p-Intersection Bodies

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Acta Mathematica Sinica,English Series 2015年第5期31卷 777-786页

作者： Wei Dong wang ya Nan LI Department of Mathematics China Three Gorges University

For 0 〈 p 〈 1, Haberl and Ludwig defined the notions of symmetric Lp-intersection body and nonsymmetric Lp-intersection body. In this paper, we introduce the general Lp-intersection bodies. Furthermore, the Busemann... 详细信息

关键词： General Lp-intersection body Busemann-Petty problem

Weak WT_2-class of differential forms and weakly A-harmonic tensors

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Applied Mathematics(A Journal of Chinese Universities) 2010年第3期25卷 359-366页

作者： GAO Hong-ya wang yan-yan College of Mathematics and Computer Science Hebei University Baoding 071002 China Hebei Provincial Center of Mathematics Shijiazhuang 050016 China

In this paper, we give the definition of weak WT2-class of differential forms, and then obtain its weak reverse Holder inequality. As an application, we give an alternative proof of the higher integrability result of ... 详细信息

关键词： Weak WT2-class of differential forms weak reverse HSlder inequality weakly A-harmonic tensor,higher integrability.