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Seasonal dependency of controlling factors on the phytoplankton production in Taihu lake, China

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Journal of Environmental Sciences 2019年第2期31卷 278-288页

作者： Qiaohua Zhao Jing wang Jianjian wang Julian X.l.wang College of Hydrometeorology Nanjing University of Information Science and Technology Air Resources laboratory National Oceanic and Atmospheric AdministrationCollege Park

In this study, 44 profiles of gross primary productivity(GPP) and sunlight, along with water temperature, Chlorophyll-a(Chla) and nutrients, were observed in Meiliang Bay of Taihu lake, China, in the spring, summer, and fall seasons. Effects of water temperature, light,and nutrient concentration were examined in relation to the GPP-unit-Chla(GPP of algae per Chla). The results showed that the optimum temperature for the GPP of phytoplankton was 27.9°C, the optimal PNA-unit-Chla(photon number absorbed by phytoplankton per Chla) was 0.25(mol), and the HSCN-unit-Chla and HSCP-unit-Chla(half-saturation constants of nitrogen and phosphorus of algae per Chla) were 0.005(mg/l) and 0.0004(mg/l), respectively. The seasonal dependency of the effect of different factors on the GPP was analyzed. Compared with temperature and nutrients, light was found to be the most important factor affecting the GPP during the three seasons. The effect of temperature and nutrients on the GPP of phytoplankton has obvious seasonal change. In spring, temperature was the secondary factor affecting the GPP of phytoplankton, and the effect of nutrients may be negligible in the eutrophic lake on account of temperature limit, which showed that the GPP of algae was only affected by the physical process. In summer and fall, temperature didn't affect the GPP of algae, and the presence of nutrients was the secondary factor affecting the GPP of phytoplankton. From summer to fall, effect of phosphorus was weakened and effect of nitrogen was enhanced.

关键词： Temperature limited effect Gross primary productivity Eutrophication light limit Optimum temperature Half-saturation constants

New generations of dihydropyridines for treatment of hypertension

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Journal of Geriatric Cardiology 2017年第1期14卷 67-72页

作者： Angela l wang Costantino Iadecola Gang wang Premed Program Washington University in St. Louis St. Louis MO USA Feil Brain and Mind Research Institute Weill Cornell Medicine New York NY USA

Since the calcium channel blocker （CCB） has become one of the most prescribed agents for antihypertensive monotherapy in the world, this brief review will focus on the recent research and development of the dihydropyridine （DHP） CCB, addressing pharmacological mecha- nisms for the clinical efficacy of the third and fourth generations of the DHP CCBs, especially on their possible central mechanisms underlying lowering blood pressure.

关键词： Central nervous system Dihydropyridine Hypertension Voltage-gated calcium channel blocker

Three-dimensional dynamics of supported pipes conveying fluid

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Acta Mechanica Sinica 2017年第6期33卷 1065-1074页

作者： l.wang T.l.Jiang H.l.Dai Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China Hubei Key laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074 China

This paper deals with the three-dimensional dynamics and postbuckling behavior of flexible supported pipes conveying fluid, considering flow velocities lower and higher than the critical value at which the buckling instability occurs. In the case of low flow velocity, the pipe is stable with a straight equilibrium position and the dynamics of the system can be examined using linear theory. When the flow velocity is beyond the critical value, any motions of the pipe could be around the postbuckling configuration(non-zero equilibrium position) rather than the straight equilibrium position, so nonlinear theory is required. The nonlinear equations of perturbed motions around the postbuckling configuration are derived and solved with the aid of Galerkin discretization. It is found, for a given flow velocity,that the first-mode frequency for in-plane motions is quite different from that for out-of-plane motions. However, the second-or third-mode frequencies for in-plane motions are approximately equal to their counterparts for out-of-plane motions, keeping almost constant values with increasing flow velocity. Moreover, the orientation angle of the postbuckling configuration plane for a buckled pipe can be significantly affected by initial conditions, displaying new features which have not been observed in the same pipe system factitiously supposed to deform in a single plane.

关键词： Pipe conveying fluid Three-dimensional dynamics Instability Natural frequency Postbuckling configuration

Repair of spinal cord injury by neural stem cells transfected with brain-derived neurotrophic factor-green fluorescent protein in rats A double effect of stem cells and growth factors?

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Neural Regeneration Research 2010年第17期5卷 1303-1307页

作者： Yansong wang Gang lü Department of Orthopedics First Affiliated Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

Brain-derived neurotrophic factor（BDNF）can significantly promote nerve regeneration and *** expression of the BDNF-green fluorescent protein（GFP）gene persists for a long time after transfection into neural stem ***,little is known about the biological characteristics of BDNF-GFP modified nerve stem cells in vivo and their ability to induce BDNF expression or repair spinal cord *** the present study,we transplanted BDNF-GFP transgenic neural stem cells into a hemisection model of *** with BDNF-GFP stem cells exhibited significantly increased BDNF expression and better locomotor function compared with stem cells *** therapy with BDNF-GFP transgenic stem cells can improve outcomes better than stem cells alone and may have therapeutic potential for spinal cord injury.

关键词： neural stem cells brain-derived neurotrophic factor transplantation green fluorescent protein spinal cord injury neural regeneration

Knoevenagel Condensation of Acetylacetone with AldehydesCatalyzed by a New Catalyst Indium Trichloride

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Chinese Chemical letters 1998年第2期9卷 123-124页

作者： wang, l Zhang, YM Hangzhou Univ Dept Chem Hangzhou 310028 Peoples R China

The Knoevenagel condensation of acetylacetone with aldehydes catalyzed by indium trichloride was carried out at room temperature in acetonitrile to give aryl- or alkylideneacetylacetones in moderate to good yields.

关键词： Knoevenagel condensation indium trichloride acetylacetone aldehyde

Plausible cloth animation using dynamic bending model

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Progress in Natural Science:Materials International 2008年第7期18卷 879-885页

作者： Charlie C.l. wang Department of Mechanical and Automation Engineering The Chinese University of Hong Kong Hong Kong China

Simulating the mechanical behavior of a cloth is a very challenging and important problem in computer animation. The models of bending in most existing cloth simulation approaches are taking the assumption that the cloth is little deformed from a plate shape. Therefore, based on the thin-plate theory, these bending models do not consider the condition that the current shape of the cloth under large deformations cannot be regarded as the approximation to that before deformation, which leads to an unreal static bending. [This paper introduces a dynamic bending model which is appropriate to describe large out-plane deformations such as cloth buckling and bending, and develops a compact implementation of the new model on spring-mass systems. Experimental results show that wrinkles and folds generated using this technique in cloth simulation, can appear and vanish in a more natural way than other approaches.]

关键词： Cloth animation Physically based animation Bending

Stabilization of discrete nonlinear systems based on control lyapunov functions

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Journal of Systems Engineering and Electronics 2008年第1期19卷 131-133页

作者： Cai Xiushan wang Xiaodong lü Ganyun Coll. of Mathematics Physics and Information Engineering Zhejiang Normal Univ. Jinhua 321004 P.R. China

The stabilization of discrete nonlinear systems is studied. Based on control lyapunov functions, a sufficient and necessary condition for a quadratic function to be a control lyapunov function is given. From this condition, a continuous state feedback law is constructed explicitly. It can globally asymptotically stabilize the equilibrium of the closed-loop system. A simulation example shows the effectiveness of the proposed method.

关键词： control lyapunov functions discrete systems stabilization

A review on the application of modified continuum models in modeling and simulation of nanostructures

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Acta Mechanica Sinica 2016年第1期32卷 83-100页

作者： K.F.wang B.l.wang T.Kitamura Graduate School at Shenzhen Harbin Institute of Technology Department of Mechanical Engineering Kyoto University

Analysis of the mechanical behavior of nanos- tructures has been very challenging. Surface energy and non- local elasticity of materials have been incorporated into the traditional continuum analysis to create modified continuum mechanics models. This paper reviews recent advancements in the applications of such modified continuum models in nanostructures such as nanotubes, nanowires, nanobeams, graphenes, and nanoplates. A variety of models for these nanostructures under static and dynamic loadings are men- tioned and reviewed. Applications of surface energy and nonlocal elasticity in analysis of piezoelectric nanomateri- als are also mentioned. This paper provides a comprehensive introduction of the development of this area and inspires fur- ther applications of modified continuum models in modeling nanomaterials and nanostructures.

关键词： Surface elasticity Nonlocal continuum Nanotubes Nanobeams Nanoplates Modeling andsimulations

Active metal brazing of SiO2–BN ceramic and Ti plate with Ag–Cu–Ti＋BN composite filler

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Journal of Materials Science & Technology 2017年第11期33卷 1392-1401页

作者： Z.W.Yang C.l.wang Y.wang l.X.Zhang D.P.wang J.C.Feng Tianjin Key lab of Advanced Joining Technology School of Materials Science and Engineering Tianjin University Tianjin 300072 China State Key lab of Advanced Welding andJoining Harbin Institute of Technology Harbin 150001 China

SiO2–BN ceramic and Ti plate were joined by active brazing in vacuum with Ag–Cu–Ti＋BN composite *** effect of BN content,brazing temperature and time on the microstructure and mechanical properties of the brazed joints was *** results showed that a continuous Ti N–Ti B2reaction layer formed adjacent to the SiO2–BN ceramic,whose thickness played a key role in the bonding *** Ti–Cu compound layers,Ti2Cu,Ti3Cu4,Ti Cu2and Ti Cu4,were observed to border Ti substrate due to the strong affinity of Ti and Cu compared with *** central part of the joint was composed of Ag matrix,over which some fine-grains *** added BN particles reacted with Ti in the liquid filler to form fine Ti B whiskers and Ti N particles with low coefficients of thermal expansion（CTE）,leading to the reduction of detrimental residual stress in the joint,and thus improving the joint *** maximum shear strength of 31 MPa was obtained when 3 wt%BN was added in the composite filler,which was 158%higher than that brazed with single Ag–Cu–Ti filler *** morphology and thickness of the reaction layer adjacent to the parent materials changed correspondingly with the increase of BN content,brazing temperature and holding *** on the correlation between the microstructural evolution and brazing parameters,the bonding mechanism of SiO2–BN and Ti was discussed.

关键词： SiO2–BN ceramic BN particles Microstructure Mechanical properties