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991.
Wen-Rui Shan Bo Tian 《Communications in Nonlinear Science & Numerical Simulation》2012,17(12):4559-4564
Variable-coefficient nonlinear evolution equations have occurred in such fields as plasma physics, arterial mechanics, nonlinear optics and Bose–Einstein condensates. This paper is devoted to giving some transformations to convert the original nonlinear evolution equations, e.g., the variable-coefficient nonlinear Schrödinger, generalized Gardner and variable-coefficient Sawada–Kotera equations to simpler ones or even constant-coefficient ones. Based on some constraints, we simplify the original equations and derive the associated chirp solitons, Lax pairs, and Bäcklund transformations from the original equations by means of the aforementioned transformations. 相似文献
992.
Haitao Zhang Zaihang Zheng Xuejun Cui Hongyan Wang Mei Han 《Journal of mathematical chemistry》2010,48(3):720-732
In order to quantify and predict the water resistance of membrane, a multi-scales association model was built up based on
the Fick’s second law. Two water resistance indexes, balance time and seepage velocity, were put forward and calculated by
the model for measuring the property of membrane water resistance. The association model linked macro-scale factors and micro-scale
parameters together. The influence of macro-scale factors, environmental temperature and membrane thickness, and micro-scale
parameters, water molecules diffusivity, membrane saturated water absorption rate and water escape concentration, were discussed.
The properties of water resistances for two groups including 10 waterborne acrylate membranes samples were measured for validating
the indexes calculated by the model. The well consistency between the results of calculations and experiments proved that
the method of multi-scales association modeling for quantifying and predicting the membrane water resistance was feasible. 相似文献
993.
Bis(imino)pyridine palladium(II) complexes 3 and 4 of type [PdCl(L)PF6] are found to be efficient catalysts for Suzuki–Miyaura reactions of aryl halides and arylboronic acids. The reactions proceed smoothly to generate the corresponding biaryl compounds in moderate to excellent yields. The synthesis of various fluorinated biphenyl derivatives was successfully achieved by the complex 4 catalyzed the Suzuki–Miyaura reaction in the presence of surfactants bearing a long alkyl chain. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
994.
Mei Wan Zhenjing Zhuang Jianyuan Dai Dan Xiao 《Russian Journal of Electrochemistry》2011,47(1):96-101
An amperometric sensor using foam nickel electrode as the working electrode for the measurement of ethanol in alkaline solution
has been developed. Cyclic voltammetry and chronoamperometry are employed to analyze electrochemical behavior of the electrode.
The results show that the oxidation of ethanol is more efficient on the foam nickel electrode than that on the nickel foil
electrode. The sensor exhibits a good linear relationship between response current and ethanol concentration in the range
of 4 to 1400 ppm with a detection limit of 0.8 ppm. The sensitivity and the response time of the sensor are 4.63 μA/ppm and
10 s respectively. Additionally, the sensor has 60 days shelf-life time at least. 相似文献
995.
996.
Orazio Attanasi Paolino Filippone Amedeo Mei Franco Serra-Zanetti 《Journal of heterocyclic chemistry》1986,23(1):25-28
The direct synthesis of a new class of unknown 1-heterocyclamino-3-carbonylpyrroles and 1-heterocyclamino-3-carboxypyrroles by copper(II) chloride-catalyzed reaction of heterocyclic conjugated azoalkene derivatives with β-diketones and β-ketoesters is reported. 相似文献
997.
实验研究发现抽运功率密度(或抽运能量)的波动引起的受激布里渊散射(SBS)反射率的不稳定程度受实验参数(抽运能量、介质气压和透镜焦距)的影响.当抽运能量、介质气压和透镜焦距这三个参数同时满足下列条件时可以获得稳定的输出:抽运能量超过5倍的SBS阈值,介质气压在16×105Pa和透镜焦距在15—50cm的范围内;同时还发现当改变实验参数时SBS反射率与稳定性的变化规律完全一致,反射率越高稳定性越好.通过理论分析得到 SBS反射率的相对稳定度实际上是受GIL因子的影响,理论计算与实验符合得很好.
关键词:
KrF激光
受激布里渊散射
反射率
稳定度 相似文献
998.
Ke Min Mei Li Krzysztof Matyjaszewski 《Journal of polymer science. Part A, Polymer chemistry》2005,43(16):3616-3622
Spontaneous gradient copolymers were prepared in both bulk and miniemulsion systems via Atom Transfer Radical Polymerization (ATRP) utilizing a Simultaneous Reverse and Normal Initiation (SR & NI) process. Both instantaneous and cumulative compositions were used to characterize the gradient copolymers. The gradient copolymers were obtained with an array of gradient compositions ranging from a subtle to strong variation in monomer distribution along the polymer backbones, depending on the ratio of comonomers initially added to the copolymerization system. The compositions of the gradient copolymer produced in miniemulsion systems were similar to those generated in bulk. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3616–3622, 2005 相似文献
999.
1000.
1,1’-联-2-萘酚硼烷的辛可宁和麻黄碱衍生物的合成单自兴,孙杰,段标,杨洗,赵德杰(武汉大学化学系,武汉,430072)关键词1,1’-联-2-萘酚,硼烷,辛可宁,麻黄碱,硼烷配合物,合成中国法分类号O627·31l,l’一联一2一条酚在大环化学... 相似文献