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MODIFICATION OF SODIUM SALT OF PARTIALLY CARBOXYMEThYLATED TAMARIND kERNEL POWDER ThROUGh GRAFTING WITh ACRYLONITRILE: SYNThESIS, ChARACTERIZATION AND SWELLING BEhAVIOR

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Chinese Journal of Polymer Science 2013年第12期31卷 1670-1684页

作者： J.h.Trivedi J.R.Jivani k.h.Patel h.C.Trivedi P.G.Dept.of Chemistry Sardar Patel UniversityVallabh Vidyanagar Amneal Phamaceuticals

A graft copolymer of polyacrylonitrile （PAN） with sodium salt of partially carboxymethylated tamarind kernel powder （Na-PCMTkP, DS ^-= 0.15） was synthesized by using ceric ammonium nitrate （CAN） as a redox initiator in an aqueous medium. The optimum reaction conditions for affording maximum percentage of grafting were established by successively varying reaction conditions such as concentrations of nitric acid, CAN, monomer （AN） as well as reaction time, temperature and amount of substrate. The influence of these reaction conditions on the grafting yields was discussed. The kinetic scheme of free radical graft copolymerization was proposed and the experimental results were found to agree very well with the proposed kinetic scheme. The graft copolymer （Na-PCMTkP-g-PAN, percentage of grafting G = 413.76% and percentage of grafting efficiency GE = 96.48%） sample synthesized under the established optimized reaction conditions was hydrolyzed by 0.7 mol-L l NaOh solution at 90-95 ℃ to yield the superabsorbent hydrogel, h-Na-PCMTkP-g-PAN. The swelling behavior of the hydrogel was studied by carrying out its absorbency measurements in low conductivity water, 0.15 mol·L^-1 salt （NaCl, CaCl2 and AlCl3） solutions and simulated urine （SU） solution at different timings. FTIR, TGA and SEM techniques were used to characterize the products.

关键词： Sodium salt of partially carboxymethylated tamarind kernel powder Acrylonitrile Graft copolymerization Superabsorbent hydrogels Swelling behavior.

Impact of wind power generating system integration on frequency stabilization in multi-area power system with fuzzy logic controller in deregulated environment

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Frontiers in Energy 2015年第1期9卷 7-21页

作者： Y. k. BhATEShVAR h. D. MAThUR h. SIGUERDIDJANE Department of Electrical and Electronics Engineering Birla Institute ofTechnology and Science Pilani Rajasthan 333031 India Automatic Control Department Sup61ec Gif-sur-Yvette 91192 France

Among the available options for renewable energy integration in existing power system, wind power is being considered as one of the suited options for future electrical power generation. The major constraint of wind power generating system （WPGS） is that it does not provide inertial support because of power electronic converters between the grid and the WPGS to facilitate frequency stabilization. The proposed control strategy suggests a substantial contribution to system inertia in terms of short-term active power support in a two area restructured power system. The control scheme uses fuzzy logic based design and takes frequency deviation as input to provide quick active power support, which balances the drop in frequency and tie-line power during transient conditions. This paper presents a comprehensive study of the wind power impact with increasing wind power penetration on frequency stabilization in restructured power system scenario. Variation of load conditions are also analyzed in simulation studies for the same power system model with the proposed control scheme. Simula- tion results advocates the justification of control scheme over other schemes.

关键词： two area power system automatic generationcontrol wind power generating system (WPGS) deregu-lated environment fuzzy logic controller (FLC)

REVISED k-ε TURBULENCE MODEL IN ELECTROMAGNETIC CONTINUOUS CASTING OF MELT

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Acta Metallurgica Sinica(English Letters) 2003年第5期16卷 395-400页

作者： h.F. huo and B.k. LiDepartment of Thermal Engineering, School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China. Dept. of Thermal Eng. Sch. of Mat. and Metall. Northeastern Univ. Shenyang 110004 China

The research is motivated by the ongoing the electromagnetic continuous casting of molten metal. The revised k-ε model considering the effect of magnetic field application was derived. The specific model equations for the electromagnetic braking were used to calculate the velocity distribution in the continuous casting mold of steel. The results show that the revised k-ε model considering the effect of magnetic field application tends to suppress the production of turbulence and difference between the conventional and revised k-e model is small.

关键词： revised k-ε turbulence model electromagnetic continuous casting magnetic field

ThE -PROBLEM FOR holOMORPhIC (0,2)-FORMS ON PSEUDOCONVEX DOMAINS IN SEPARABLE hILBERT SPACES AND D.F.N. SPACES

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Chinese Annals of Mathematics,Series B 2002年第1期23卷 67-74页

作者： J.LEE k.h.ShON DepartmentofMathematicsEducation AndongNationalUniversityAndong760-749Korea DepartmentofMathematics PusanNationalUniversityPusan609-735Korea

This paper shows that the 8-problem for holomorphic (0, 2)-forms on hubert spaces is solv-able on pseudoconvex open subsets. By using this result, the authors investigate the existence of the solution of the -equation... 详细信息

关键词： -prob1em Pseudoconvex domain Nuclear operator D.F.N. space

Review of micromachining of ceramics by etching

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中国有色金属学会会刊：英文版 2009年第B9期19卷 1-16页

作者： h.T.TING k.A.ABOU-EL-hOSSEIN h.B.ChUA School of Engineering and Science Curtin University of Technology (Sarawak Campus) Department of Mechatronics Nelson Mandela Metr opolitan University

In the last two decades, there has been an enormous surge in interest in ceramic materials and, as a result, there have been significant advances in their development and applications. Their inherent properties, such as capability of operating at temperatures far above metals, high level of hardness and toughness, low coefficient of thermal expansion and high thermal conductivity rendered ceramics to be one of the leading engineering materials. Many research works have been conducted in the past few years on machining of advanced ceramics using different processing methods in order to obtain a better surface roughness, higher material removal rate and improved tool life. Micromachining using chemical etching is one of those methods that do not involve the problem of tool life and direct tool-work piece contact. however, only a few research works have been done on micromachining of ceramics using chemical etching. hence, study of chemical machining of advanced ceramics is still needed as the process has found wide application in the industry because of its relative low operating costs. In this work, we summarize the recent progresses in machining of different types of advanced ceramics, material processing methods such as wet etching and dry etching, and finally the prospects for control of material removal rate and surface quality in the process of ceramic micromachining.

关键词：陶瓷材料化学蚀刻表面粗糙度机械加工过程陶瓷加工刀具寿命材料去除率高温作业

Entanglement and Other Nonclassical Properties of Two Two-Level Atoms Interacting with a Two-Mode Binomial Field: Constant and Intensity-Dependent Coupling Regimes

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Communications in Theoretical Physics 2015年第10期64卷 439-446页

作者： M.k.Tavassoly h.hekmatara Atomic and Molecular Group Faculty of Physics Yazd University Photonic Research Group Engineering Research Center Yazd University The Laboratory of Quantum Information Processing Yazd University

In this paper, we consider the interaction between two two-level atoms and a two-mode binomial field with a general intensity-dependent coupling regime. The outlined dynamical problem has explicit analytical solution, by which we can evaluate a few of its physical features of interest. To achieve the purpose of the paper, after choosing a particular nonlinearity function, we investigate the quantum statistics, atomic population inversion and at last the linear entropy of the atom-field system which is a good measure for the degree of entanglement. In detail, the effects of binomial field parameters, in addition to different initial atomic states on the temporal behavior of the mentioned quantities have been analyzed. The results show that, the values of binomial field parameters and the initial state of the two atoms influence on the nonclassical effects in the obtained states through which one can tune the nonclassicality criteria *** intensity-dependent coupling function equal to 1 reduces the results to the constant coupling case. By comparing the latter case with the nonlinear regime, we will observe that the nonlinearity disappears the pattern of collapse-revival phenomenon in the evolution of Mandel parameter and population inversion(which can be seen in the linear case with constant coupling), however, more typical collapse-revivals will be appeared for the cross-correlation function in the nonlinear case. Finally, in both linear and nonlinear regime, the entropy remains less than(but close to) 0.5. In other words the particular chosen nonlinearity does not critically affect on the entropy of the system.

关键词： Jaynes–Cummings model atom-field interaction two-m

Order Environments of Topological Spaces

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Acta Mathematica Sinica,English Series 2004年第5期20卷 943-948页

作者： J.h.LIANG k.kEIMEL Department of Mathematics Sichuan Univ.Chengdu 610064P.R.China Department of Mathematics Darmstadt Univ.Germany

In this paper it is proved that a space may be realized as the set of the maximal elementsin a continuous poset if and only if it is Tychonoff.

关键词： Domain environment Weakly complete Tychonoff space

high-cycle Fatigue Life Extension of Glass Fiber/Polymer Composites with Carbon Nanotubes

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 167-173页

作者： Christopher S Grimmer C k h Dharan Berkeley Composites Laboratory University of California 5135 Etcheverry Hall Berkeley CA94720-1740 USA

The present work shows that the addition of small volume fractions of multi-walled carbon nanotubes （CNTs） to the matrix results in a significant increase in the high-cycle fatigue life. It is proposed that carbon nanotubes tend to inhibit the formation of large cracks by nucleating nano-scale damage zones. In addition, the contribution to energy absorption from the fracture of nanotubes bridging across nano-scale cracks and from nanotube pull-out from the matrix are mechanisms that can improve the fatigue life. An energy-based model was proposed to estimate the additional strain energy absorbed in fatigue. The distributed nanotubes in the matrix appear to both distribute damage as well as inhibit damage propagation resulting in an overall improvement in the fatigue strength of glass fiber composites.

关键词： glass fiber composites carbon nanotubes fatigue strain energy

A cellular automata traffic flow modeling of desired speed variability

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Chinese Physics B 2013年第1期22卷 574-577页

作者： k. Bentaleb k. Jetto h. Ez-Zahraouy A. Benyoussef Laboratoire de Magnétisme et de Physique des hautes Energies associéau CNRST (URAC 12) Département de physique B.P. 1014 Facultédes sciences Université Mohammed V Agdal Rabat Morocco Ecole hassania des Travaux Publics km 7 Route d'El Jadida BP8108 Oasis Casablanca Morocco Institute of Nanomaterials and Nanotechnologies INANOTECH MACsIR Rabat Morocco hassan II Academy of Science and Technology Rabat Morocco

The satisfaction rate of desired velocity in the case of a mixture of fast and slow vehicles is studied by using a cellular automaton method. It is found that at low density the satisfaction rate depends on the maximal velocity. however, the behavior of the satisfaction rate as a function of the coefficient of variance is independent of the maximal velocity. This is in good agreement with empirical results obtained by Lipshtat [Phys. Rev. E 79 066110 （2009）]. Furthermore, our numerical result demonstrates that at low density the satisfaction rate takes higher values, whereas the coefficient of variance is close to zero. The coefficient of variance increases with increasing density, while the satisfaction rate decreases to zero. Moreover, we have also shown that, at low density the coefficient variance depends strongly on the probability of overtaking.

关键词： traffic celluar automata satisfaction coefficient desired speed