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Evaluating the photovoltaic properties of two conjugated polymers synthesized by Suzuki polycondensation and direct C–H activation

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Science China Chemistry 2015年第2期58卷 286-293页

作者： Hedi wei heng Lu Tao Fang Zhishan Bo Beijing Key Laboratory of Energy Conversion and Storage Materials Key Laboratory of Theoretical and Computational PhotochemistryMinistry of Education College of Chemistry Beijing Normal University

Two conjugated polymers HXS-1 and PDFCDTBT were prepared by direct C–H activation and Suzuki polycondensation and their chemical structures were characterized by 1H NMR *** molecular weight of conjugated polymer synthesized by direct C–H activation is lower than the corresponding polymers prepared by Suzuki *** polymers synthesized by direct C–H activation have considerable solubility in common organic solvents and form amorphous *** photovoltaic property of conjugated polymers synthesized by direct C–H activation is inferior to the corresponding polymers synthesized by Suzuki polycondensation.

关键词： polymer solar cells Suzuki polycondensation direct C-H activation conjugated polymers donor materials

Droop Control Method to Achieve Maximum Power Output of Photovoltaic for Parallel Inverter System

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1636-1645页

作者： wei Zhang zhong Zheng Hongpeng Liu School of Electrical Engineering Northeast Electric Power UniversityJilin 132012China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China

In general,the power distribution of a parallel inverter is achieved by the use of droop control in a microgrid system,which consists of PV inverters and non-regeneration energy source inverters without energy storage devices in an islanded *** the shared load power is no more than the available maximum PV inverter output power,then there is a power waste for the PV *** addition,due to the intermittency of PV sources,the system may become unstable if the shared load power is more than the available maximum power output of the PV(MPO-PV)***,in order to avoid power waste and potential instability caused by insufficient PV power by traditional droop control,this paper recommends an improved droop control scheme to maximize the power output of PV *** required by the load,the remaining power is composed of the other inverters,which can effectively improve the utilization rating of renewable energy sources and system *** the same time,according to the system stability analysis based on small signal modeling,it has been designed around the droop coefficients of the improved droop control *** the end,the simulation and experimental results show that the suggested scheme has a varied validity and robustness.

关键词： Improved droop control maximum power output of the PV(MPO-PV) parallel inverter system PV cells small signal modeling

Correction Model for Stall Delay on Rotating Blades

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第1期33卷 60-66页

作者： zhong wei Wang Tongguang Jiangsu Key Laboratory of Hi-Tech Research for Wind Turbine Design Nanjing University of Aeronautics and Astronautics

Stall delay is an important phenomenon on wind turbine *** makes the maximum aerodynamic load of a rotating blade much higher than the one predicted without a correction.A new stall delay model is established here based on the investigation of the flow around a rotating *** investigation results indicate that the shrink of separation vortex caused by centrifugal force is the major reason for the stall *** factors related to the rotational effects are considered in the proposed model,such as rotating speed,inflow velocity,local chord length and radial ***,the model are validated on the NREL PhaseⅣ blade and the results demonstrate that the accuracy of the aerodynamic prediction for the blade is significantly improved as the model is applied.

关键词： wind turbine rotational effects stall delay computational fluid dynamics(CFD)

An Efficient Mapped WENO Scheme Using Approximate Constant Mapping

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Numerical Mathematics(Theory,Methods and Applications) 2022年第1期15卷 1-41页

作者： Ruo Li wei zhong CAPT LMAMPeking UniversityBeijing 100871China School of Mathematical Sciences Peking UniversityBeijing 100871China Northwest Institute of Nuclear Technology Xi’an 710024China

We present a novel mapping approach for WENO schemes through the use of an approximate constant mapping function which is constructed by employing an approximation of the classic signum *** new approximate constant mapping function is designed to meet the overall criteria for a proper mapping function required in the design of the WENO-PM6 *** WENO-PM6 scheme was proposed to overcome the potential loss of accuracy of the WENO-M scheme which was developed to recover the optimal convergence order of the WENO-JS scheme at critical *** new mapped WENO scheme,denoted as WENOACM,maintains almost all advantages of the WENO-PM6 scheme,including low dissipation and high resolution,while decreases the number of mathematical operations remarkably in every mapping process leading to a significant improvement of *** convergence rates of the WENO-ACM scheme have been shown through one-dimensional linear advection equation with various initial *** results of one-dimensional Euler equations for the Riemann problems,the Mach 3 shock-density wave interaction and the Woodward-Colella interacting blastwaves are improved in comparison with the results obtained by the WENO-JS,WENO-M and WENO-PM6 *** experiments with two-dimensional problems as the 2D Riemann problem,the shock-vortex interaction,the 2D explosion problem,the double Mach reflection and the forward-facing step problem modeled via the two dimensional Euler equations have been conducted to demonstrate the high resolution and the effectiveness of the WENO-ACM *** WENOACM scheme provides significantly better resolution than the WENO-M scheme and slightly better resolution than the WENO-PM6 scheme,and compared to the WENOM and WENO-PM6 schemes,the extra computational cost is reduced by more than 83%and 93%,respectively.

关键词： WENO approximate constant mapping hyperbolic problems high resolution low computational cost

Detecting Intensity Evolution of the Western North Pacific Super Typhoons in 2016 Using the Deviation Angle Variance Technique with FY Data

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Journal of Meteorological Research 2019年第1期33卷 104-114页

作者： Meng YUAN wei zhong Institute of Meteorology and Oceanography National University of Defense Technology

This paper analyzes the complete lifecycle of super typhoons in 2016 in the western North Pacific(WNP) using the deviation angle variance technique(DAV-T). Based on the infrared images from Fengyun(FY) satellites, the DAV-T enables quantification of the axisymmetry of tropical cyclones(TCs) by using the DAV values; and thus, it helps improve the capability of TC intensity estimation. Case analyses of Super Typhoons Lionrock and Meranti were performed to explore the distribution characteristics of the DAV values at the various stages of TC evolution. The results show that the minimum DAV values(i.e., map minimum values: MMVs) gradually decreased and their locations constantly approached the circulation center with enhancement of the TC organization; however, when a ring or disk structure was formed around a TC, significant changes in MMV locations were no longer observed. Nonetheless,when large-scale non-closed deep convective cloud clusters appeared at the early stage or the dissipation stage of the typhoon, the axisymmetry of the TC was poor and the MMV locations tended to lie in the most convective region rather than in the TC circulation center. Overall, the MMVs and their locations, respectively, exhibited a strong correlation with the TC intensity and circulation center, and the correlation increased as the TCs became stronger. Combined with the China Meteorological Administration BestTrack dataset(CMA-BestTrack), statistical analysis of all research samples reveals that the correlation coefficient between the MMVs and maximum surface wind speeds(Vmax) was –0.80; the root mean square error(RMSE) of relative distance between the MMV locations and TC centers was 140.3 km; and especially, when the samples below the tropical depression(TD) intensity were removed, the RMSE of the relative distance decreased dramatically to 95.0 km. The value and location of the MMVs could be used as important indicators for estimating TC intensity and center.

关键词： deviation angle variance technique(DAV-T) axisymmetry super typhoon Fengyun(FY) satellites

Nanomedicine strategies for sustained,controlled,and targeted treatment of cancer stem cells of the digestive system

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World Journal of Gastrointestinal Oncology 2016年第10期8卷 735-744页

作者： Fang-Yuan Xie wei-heng Xu Chuan Yin Guo-Qing Zhang Yan-Qiang zhong Jie Gao Department of Pharmacy Shanghai Eastern Hepatobiliary Surgery Hospital Department of Pharmaceutical Sciences School of Pharmacythe Second Military Medical University Department of Biochemical Pharmacy School of Pharmacythe Second Military Medical University Department of Gastroenterology Changzheng HospitalSecond Military Medical University

Cancer stem cells(CSCs) constitute a small proportion of the cancer cells that have self-renewal capacity and tumor-initiating *** have been identified in a variety of tumors,including tumors of the digestive *** exhibit some unique characteristics,which are responsible for cancer metastasis and ***,the development of effective therapeutic strategies against CSCs plays a key role in increasing the efficacy of cancer *** potential approaches to target CSCs of the digestive system have been explored,including targeting CSC surface markers and signaling pathways,inducing the differentiation of CSCs,altering the tumor microenvironment or niche,and inhibiting ATP-driven efflux ***,conventional therapies may not successfully eradicate CSCs owing to various problems,including poor solubility,stability,rapid clearance,poor cellular uptake,and unacceptable *** strategies,which include drug,gene,targeted,and combinational delivery,could solve these problems and significantly improve the therapeutic *** review briefly summarizes the ongoing development of strategies and nanomedicine-based therapies against CSCs of the digestive system.

关键词： Nanomedicine Cancer stem cells Digestive system Drug delivery Gene delivery

Sequential maneuvering decisions based on multi-stage influence diagram in air combat

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Journal of Systems Engineering and Electronics 2007年第3期18卷 551-555页

作者： zhong Lin Tong Ming'an zhong wei Zhang Shengyun Dept. of Electronic Information Northwestern Polytechnical Univ. Xi'an 710072 P. R. China School of Electronic Science Jiangxi Univ. of Finance and Economics Nanchang 330013 P. R. China

A multi-stage influence diagram is used to model the pilot＇s sequential decision making in one on one air combat. The model based on the multi-stage influence diagram graphically describes the elements of decision process, and contains a point-mass model for the dynamics of an aircraft and takes into account the decision maker＇s preferences under uncertain conditions. Considering an active opponent, the opponent＇s maneuvers can be modeled stochastically. The solution of multistage influence diagram can be obtained by converting the multistage influence diagram into a two-level optimization problem. The simulation results show the model is effective.

关键词： multi-stage influence diagram air combat maneuvering decision hierarchical optimization.

Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies

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Neural Regeneration Research 2025年第3期20卷 779-793页

作者： Guangyong Zhang Qing Yao Chubing Long Pengcheng Yi Jiali Song Luojia Wu wei Wan Xiuqin Rao Yue Lin Gen wei Jun Ying Fuzhou Hua Department of Anesthesiology the Second Affiliated Hospital of Nanchang UniversityNanchangJiangxi ProvinceChina Key Laboratory of Anesthesiology of Jiangxi Province NanchangJiangxi ProvinceChina

Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.

关键词： blood–brain barrier macrophages monocytes multiple sclerosis neuroinflammation review therapy

Numerical Approximation of Stochastic Theta Method for Random Periodic Solution of Stochastic Differential Equations

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 689-701页

作者： Rong wei Chuan-zhong CHEN School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China School of Science Hainan UniversityHaikou 570228China

In this paper,we make use of stochastic theta method to study the existence of the numerical approximation of random periodic *** prove that the error between the exact random periodic solution and the approximated on... 详细信息

关键词： Stochastic theta method random periodic solution numerical approximation