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Effect of nutrient level on phytoplankton community structure in different water bodies

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Journal of Environmental Sciences 2010年第1期22卷 32-39页

作者： Wei Zhu lei wan Lianfang Zhao College of Environmental Science and Engineering Hohai University Nanjing 210098 China College of Environmental Engineering Xuzhou Institute of Technology Xuzhou 221008 China

Increasing levels of pollution within water bodies can cause eutrophication and an associated rapid growth in and reproduction of phytoplankton. Although most frequently occurring in bodies of water such as lakes and dams, in recent years an increasing number of river systems in China have suffered serious algal blooms. The community structure of phytoplankton may differ, however, dependent on the hydrodynamic conditions and nutrient levels within the water body. The field investigation results obtained from a stagnant river in Suzhou City and Taihu Lake, China, showed that in water with higher concentrations of nitrogen and phosphorus, Chlorophyta became the predominant species and in water with lower concentrations of nitrogen and phosphorus, Cyanobacteria became the predominant species. Growth experiments with competitive species, Microcystis aeruginosa Kutz and Scenedesmus quadricauda （Turp.）, were conducted at three different nutrient levels. The biomass of algae in pure and mixed cultures was measured under conditions of different N/P ratios at oligotrophic, eutrophic and hypertrophic nutrient levels. The results indicated that the most suitable state for the growth and reproduction of M. aeruginosa and S. quadricauda were eutrophic conditions in both pure and mixed cultures. Under competition, however, the lower medium nutrient levels favoured M. aeruginosa, while the higher medium nutrient levels better suited S. quadricauda. Under similar hydrodynamic conditions, the community structure of phytoplankton in the water body was determined by the dominant species in competition for nutrients.

关键词： phytoplankton community structure nutrients level N/P ratio

Reactive-sintering B_4C matrix composite for armor applications

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Rare Metals 2020年第5期39卷 529-544页

作者： Chao Wu Yun-Kai Li Chun-lei wan Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing Institute of TechnologyNanjing 211167China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

The B4C matrix composite intended for armor applications still presents restrictions,such as low sintering density,production of large parts and inherited brittleness Herein,research on this topic is discussed in *** the material outlook of armor applications is organized from the development of composite armor and ceramic materials for armor to the B4C matrix composite and reactive-sintering *** the second section,the technologies are reviewed for reactive pressureless sintering reactive hot-pressing sintering,reactive discharge plasma sintering and self-propagating high-temperature sintering Thereafter,our previous works on the TiB2/SiC/B4C composite and laminated Ti/B4C composite are employed to illustrate their microstructural evolution,phase transformation and fracture *** studies provide a potential method for producing tough and high-strength ceramic composites for armor *** the fina section,the mechanism,evaluation method and influencing factors of anti-penetration for ceramic armor and B4C matrix composite are reviewed.

关键词： Composite armor B4C matrix composite Reactive sintering Mechanical properties

Effect of Xinfeng capsule on nuclear factor kappa B/tumor necrosis factor alpha and transforming growth factor beta 1/Smads pathways in rats with cardiac injuries induced by adjuvant arthritis

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Journal of Traditional Chinese Medicine 2016年第1期36卷 92-100页

作者： Huang Chuanbing wan lei Liu Jian Department of Rheumatism Immunity The First Affiliated Hospital Anhui University of Chinese Medicine

OBJECTIVE: To investigate effects of Xinfeng capsule(XFC) on cardiac function in rats with adjuvant arthritis(AA) and explore the mechanism of these ***: Forty-eight rats were randomly divided into normal control(NC), model control(MC), methotrexate(MTX) and XFC groups of equal size. In all groups except for the NC group, 0.1 m L Freund's complete adjuvant(FCA) was intracutaneously injected in the right rear vola pedis to induce inflammation. Drugs were applied beginning 19 days after induction of inflammation. Normal saline was administered to the NC and MC groups and 1 mg/100 g MTX(weekly) and 0.12 g/100 g XFC(daily) to the MTX and XFC groups, respectively. Rats were sacrificed after 30 day of treatment. Toe swelling degree(TSD), arthritis index(AI), cardiac function and expression of nuclear factor kappa B(NF-κB) / tumor necrosis factor alpha(TNF-α) and transforming growth factor beta 1(TGF-β1)/Smads pathway proteins were ***: In the MC group, TSD and AI were greatly increased, while parameters of cardiac function were decreased and morphological analysis showed myocardial cell damage. Expression of TNF-α, NF-κB, Smad2, P-Smad2, Smad4 and TGF-β1 proteins were elevated in cardiac tissue, while Smad7 expression was *** and AI values closely correlated to parameters of cardiac function and to levels of proteins in the NF-κB/TNF-α and TGF-β1/Smads pathways. Certain correlations were identified among TGF-β1 and NF-κB, Smad2, P-Smad2 and *** XFC intervention, both TSD and AI were decreased and parameters of cardiac function and ultrastructure of myocardial cells *** of NF-κB, Smad2, and Smad4 proteins were greatly decreased and Smad7 expression was elevated, as compared with levels in the MC and MTX ***: XFC regulates expression of proteins in the NF-κB/TNF-α and TGF-β1/Smads pathways, decreases immune complex deposition in cardiac tissue and improves cardiac function in AA rats via upregulation o

关键词： Arthritis, Experimental Heart functiontests Xinfeng capsule NF-kappa B Tumor necrosisfactor-alpha Transforming growth factor-β

Energy leakage in OFDM sparse channel estimation:The drawback of OMP and the application of image deblurring

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Digital Communications and Networks 2024年第5期10卷 1280-1288页

作者： Gang Qiao Xizhu Qiang lei wan Hanbo Jia Acoustic Science and Technology Laboratory Harbin Engineering University Key Laboratory of Marine Information Acquisition and Security (Harbin Engineering University) Ministry of Industry and Information Technology College of Underwater Acoustic Engineering Harbin Engineering University School of Informatics Xiamen University Key Laboratory of Underwater Acoustic Communication and Marine Information Technology (Xiamen University) Ministry of Education

In this paper,in order to reduce the energy leakage caused by the discretized representation in sparse channel estimation for Orthogonal Frequency Division Multiplexing(OFDM) systems,we systematically have analyzed the optimal locations of atoms with discrete delays for each path reconstruction from the perspective of linear fitting ***,we have investigated the adverse effects of the non-ideal inner product function on the iteration in one of the most widely used channel estimation method,Orthogonal Matching Pursuit(OMP).The study shows that the distance between the selected atoms for each path in OMP can be larger than the sampling interval,which prevents OMP-based methods from achieving better *** overcome this drawback,the image deblurring-based channel estimation method,in which the channel estimation problem is analogized to one-dimensional image deblurring,was proposed to improve the large compensation distance of traditional *** advantage of the proposed method was validated by the results of numerical simulation and sea trial data decoding.

关键词： Sparse channel estimation Orthogonal matching pursuit (OMP) Orthogonal frequency division multiplexing (OFDM) Linear fitting Image deblurring

Cobalt-catalyzed reductive alkynylation to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds

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Chinese Chemical Letters 2024年第7期35卷 253-258页

作者： lei wan Yizhou Tong Xi Lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： Cobalt-catalysis Cross-electrophile coupling Carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

Editorial for advanced structural ceramics technology and characteristics

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Rare Metals 2020年第5期39卷 460-462页

作者： Jing Feng Guang-Hua Liu Chun-lei wan Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

It is our great pleasure as Guest Editors of the journal‘‘Rare Metals’’to present the special issue on‘‘Advanced Structural Ceramics Technology&Characteristics.’’It provides the most recent research developments in advanced structural ceramics technology and characteristics and their applications in the potential industrial *** the twenty-first century and the following decade,industrial ceramics have made significant contributions to various fields,including electronics,communications,transports,aeronautics,astronautics,environment,and energy.

关键词： pleasure communications application

Penetrating power characteristics of half-wavelength AC transmission in point-to-grid system

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Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 123-130页

作者： Hanqing LIANG Yadong LIU lei wan Gehao SHENG Xiuchen JIANG Department of Electrical Engineering Shanghai Jiao Tong University Global Energy Interconnection Development and Cooperation Organization

With the proposed concept of global energy interconnection, half-wavelength alternating current transmission(HWACT) technology becomes of more *** lines can be adopted to establish a pointto-grid system, in which the penetrating power(PP) is produced between receiving terminals, having a significant effect on the power flow *** order to investigate this phenomenon, the PP characteristics of the HWACT system are researched in this ***, the mathematical relationship between the transmission power and terminal bus voltages of a single HWACT line is derived using the equations of a distributed parameter *** research indicates that the relationship between power and terminal voltages shows ‘‘reverse characteristics"opposite to those of regular short transmission ***, the concept and definition of PP in a point-to-grid system with two receiving terminals are proposed, and the corresponding relationship between PP and the terminal bus voltages is *** are carried out to validate the theory under different conditions, so that the accuracy and adaptiveness of the theoretical analysis can be *** addition, the results demonstrate that selecting the location for a HWACT system has demanding requirements in order to control the value of PP.

关键词： Half-wavelength alternating current transmission(HWACT) Ultra-high voltage Synchronous power grids Penetrating power(PP)

Adaptive PID control system for an autonomous underwater vehicle

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High Technology Letters 2011年第1期17卷 7-12页

作者：王波 Su Yumin wan lei Sun Yushan State Key Laboratory of Autonomous Underwater Vehicle Harbin Engineering University Harbin 150001 P. R. China

The control system of an autonomous underwater vehicle （AUV） is introduced. According to control requirements of the AUV, a simple but practical adaptive PID control method is designed The semi-physical simulation is done to test the feasibility of the control system. The neural network idea and the structure of PID controller are referred to design the adaptive PID controller. An intelligent integral is introduced to improve control precision. Compaed with traditional PID con- trollers, the adaptive PID controller has simple structure, good online adjusting ability, fast convergence and good robustness. The simulation experiments also show that the adaptive PID control system has high precision and fine antijamming ability.

关键词： autonomous underwater vehicle ( AUV) control system adaptive PID control semi-physical simulation

Visible-light induced generation of bifunctional nitrogen-centered radicals:a concise synthetic strategy to construct bicyclo[3.2.1]octane and azepane cores

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Science China Chemistry 2021年第2期64卷 274-280页

作者： wan-lei Yu Hao-Wen Jiang lei Yan Zhi-Tao Feng Yong-Chun Luo Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China Department of Chemistry University of California-DavisOne Shields AvenueDavisCA95616USA

A photocatalytic tandem cyclization of o-alkenylbenzaldehydes using pyridinium salts as the amination reagent is described.A variety of valuable seven-membered nitrogenous heterocyclic skeletons are prepared in modest to excellent yields in concise *** transformation features mild reaction conditions and exceptional functional group *** addition,combining control experiments and density functional theory(DFT)calculations on the mechanism can explain the reaction selectivity.

关键词： photoredox catalysis nitrogen-centered radicals bicyclo[3.2.1]octane azepane 1,5-hydrogen atom transfer