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61.
针对某种小型轿车,基于计算流体力学(CFD)方法研究了不同轮拱罩充满率时旋转车轮对整车气动特性的影响,并与现有理想模型的试验结果对比.结果表明:在其他参数不变的情况下,随着轮拱罩充满率的下降,整车阻力系数上升,升力系数下降,当充满率下降27%时,阻力系数上升接近20%,升力系数下降接近30%.阻力上升主要是由于轮拱罩中的气流量增加,并且受轮拱罩结构的影响,内部流动分离加剧,导致尾流区的涡量均上升,车辆背压下降;升力下降主要是因为下车身气流速度加快,导致下车身压力减小. 相似文献
62.
This paper describes a simple method of generating concentration gradients with linear and parabolic profiles by using a Christmas tree-shaped microfluidic network.The microfluidic gradient generator consists of two parts:a Christmas tree-shaped network for gradient generation and a broad microchannel for detection.A two-dimensional model was built to analyze the flow field and the mass transfer in the microfluidic network.The simulating results show that a series of linear and parabolic gradient profiles were generated via adjusting relative flow rate ratios of the two source solutions(R_L~2≥0.995 and _PR~2≥0.999),which could match well with the experimental results(R_L~2≥0.987 and _PR~2≥0.996).The proposed method is promising for the generation of linear and parabolic concentration gradient profiles,with the potential in chemical and biological applications such as combinatorial chemistry synthesis,stem cell differentiation or cytotoxicity assays. 相似文献
63.
Zhigang Feng 《Mathematical Methods of Operations Research》2013,77(3):445-457
Overlapping generations models may have a continuum of equilibria. Previous studies have been largely confined to the local analysis that linearizes the model around the steady state. However, what is true of the linearized system only applies for an unknown-sized open neighborhood of the steady state. In this paper I develop a method to diagnose the indeterminacy in overlapping generations models by computing the set of all equilibria. I also provide a procedure to simulate the economy with indeterminate equilibrium. 相似文献
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66.
Ailong Wu Zhigang Zeng 《Communications in Nonlinear Science & Numerical Simulation》2013,18(2):373-385
In this paper, we formulate and investigate a class of memristive recurrent neural networks. Two different types of anti-synchronization algorithms are derived to achieve the exponential anti-synchronization of the coupled systems based on drive–response concept, differential inclusions theory and Lyapunov functional method. The proposed anti-synchronization algorithms are simple and can be easily realized. The analysis in the paper employs results from the theory of differential equations with discontinuous right-hand side as introduced by Filippov. The obtained results extend some previous works on conventional recurrent neural networks. 相似文献
67.
Zhigang Xue Zhen Wang Dan He Xingping Zhou Xiaolin Xie 《Journal of polymer science. Part A, Polymer chemistry》2016,54(5):611-620
Cationic emulsions of triblock copolymer particles comprising a poly(n‐butyl acrylate) (PnBA) central block and polystyrene (PS) outer blocks were synthesized by activator generated by electron transfer (AGET) atom transfer radical polymerization (ATRP). Difunctional ATRP initiator, ethylene bis(2‐bromoisobutyrate) (EBBiB), was used as initiator to synthesize the ABA type poly(styrene‐b‐n‐butyl acrylate‐b‐styrene) (PS‐PnBA‐PS) triblock copolymer. The effects of ligand and cationic surfactant on polymerizations were also discussed. Gel permeation chromatography (GPC) was used to characterize the molecular weight (Mn) and molecular weight distribution (MWD) of the resultant triblock copolymers. Particle size and particle size distribution of resulted latexes were characterized by dynamic light scattering (DLS). The resultant latexes showed good colloidal stability with average particle size around 100–300 nm in diameter. Glass transition temperature (Tg) of copolymers was studied by differential scanning calorimetry (DSC). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 611–620 相似文献
68.
Shaoyong Ke Zhigang Zhang Ya-Ni Zhang Liqiao Shi Ronghua Zhou Aibing Jiang Ying Liang Ziwen Yang 《Research on Chemical Intermediates》2012,38(8):1827-1837
A novel series of ether functionalization of spiro-tetronic acid derivatives have been designed and conveniently synthesized via three steps, including esterification, one-pot heterocyclization, and etherification reactions. The target molecules have been identified on the basis of analytical spectra data. All newly synthesized compounds have been screened for their potential insecticidal activity against Heliothis armigera and Plutella xylostella compared with spirodiclofen by standard method. 相似文献
69.
Manqi Ruan Hang Zhao Gang Li Chengdong Fu Zhigang Wang Xinchou Lou Dan Yu Vincent Boudry Henri Videau Vladislav Balagura Jean-Claude Brient Peizhu Lai Chia-Ming Kuo Bo Liu Fenfen An Chunhui Chen Soeren Prell Bo Li Imad Laketineh 《The European Physical Journal C - Particles and Fields》2018,78(5):426
After the Higgs discovery, precise measurements of the Higgs properties and the electroweak observables become vital for the experimental particle physics. A powerful Higgs/Z factory, the Circular Electron Positron Collider (CEPC) is proposed. The Particle Flow oriented detector design is proposed to the CEPC and a Particle Flow algorithm, Arbor is optimized accordingly. We summarize the physics object reconstruction performance of the Particle Flow oriented detector design with Arbor algorithm and conclude that this combination fulfills the physics requirement of CEPC. 相似文献
70.