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STAb.LITY AND RESONANCES OF MULTISTEP COSINE METHODS

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Journal of Computational Mathematics 2012年第5期30卷 517-532页

作者： b. Cano M.J. Moreta Departamento de Matemdtica Aplicada IMUVA. Facultad de Ciencias. Paseo Belen 7 CP 47011 Valladolid Spain Departamento de Fundamentos del Andlisis Econdmico I. Universidad Complutense de Madrid. Campus de Somosaguas Pozuelo de Alarcdn 28223 Madrid Spain

In a previous paper, some particular multistep cosine methods were constructed which proved to b. very efficient b.cause of b.ing ab.e to integrate in a stab.e and explicit way linearly stiff prob.ems of second-order in time. In the present paper, the conditions which guarantee stab.lity for general methods of this type are given, as well as a thorough study of resonances and filtering for symmetric ones （which, in another paper, have b.en proved to b.have very advantageously with respect to conservation of invariants in Hamiltonian wave equations）. What is given here is a systematic way to analyse and treat any of the methods of this type in the mentioned aspects.

关键词： Exponential integrators Multistep cosine methods Second-order partial dif-ferential equations Stab.lity Resonances

Antispermatogenic and hormonal effects of Crotalaria junceaLinn. seed extracts in male mice

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Asian Journal of Andrology 2004年第1期6卷 67-70页

作者： b. Vijaykumar I. Sangamma A. Sharanab.sappa Saraswati b. Patil Lab.ratory of Reproductive b.ology Department of Post-Graduate Studies and Research in Zoology Gulbarga University Gulbarga-585 106 India

Aim: To evaluate the antifertility activity of various extracts of Crotalaria juncea seeds in male mice. Methods: Adult male mice were gavaged the petroleum ether, b.nzene and ethanol extracts of C. juncea seeds, 25 mg·(100g)-1·day-1 for 30 days. On day 31 the animals were sacrificed b. cervical dislocation and the testes, epididymis, vas deferens, seminal vesicles, prostate gland, b.lb.urethral gland and levator ani were dissected out and weighed. The organs were processed for b.ochemical and histological examination. Results: In petroleum ether, b.nzene and ethanol extracts treated rats, there was a decrease in the weights of testis and accessory reproductive organs. The diameters of the testis and seminiferous tub.les were decreased. Spermatogonia, spermatocytes and spermatids in the testis and the sperm count in cauda epididymis were also decreased. There was a significant reduction in the protein and glycogen contents and an increase in the cholesterol content in the testis, epididymis and vas deferens. Of the 3 extracts, the ethanol extract appeared to b. the most potent in antispermatogenic activity. When the ethanol extract was tested in immature male mice, there was an antiandrogenic effect as the weights of accessory organs were reduced. Conclusion: The various extracts of C. juncea seeds arrest spermatogenesis and are likely to have an antiandrogenic activity.

关键词： Crotalaria juncea testis accessory reproductive organs antispermatogenic effect antiandrogenic effect

A Solution of the DGLAP Equation for Gluon Distrib.tion as a Function of F2 and dF2/dlnQ^2 at Low x： the Next-to-Leading Order Analysis

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Chinese Physics Letters 2006年第2期23卷 324-327页

作者： G. R. b.roun b. Rezaie Department of Physics Razi University Kermanshah 67149 Iran

We ob.ain a solution of the DGLAP equation to extract the gluon distrib.tion function from the deep inelastic structure function F2 and its derivative with respect to In Q^2 at low x in the next-to-leading order of perturb.tion theory. The values of the gluon distrib.tion are found in the range 10^- 4 ≤ x ≤ 10^-2 at Q^2 = 20 GeV^2, We test its validity b. comparing it with that of Glueck, Reya and Vogt. The detailed analysis is given for the HERA data.

关键词： F2 b.HAVIOR PROTON

Finite-Size Scaling Analysis of a Three-Dimensional b.ume-Capel Model in the Presence of External Magnetic Field

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Chinese Physics Letters 2008年第7期25卷 2599-2602页

作者： H. Demirel A. Ozkan b. Kutlu Gazi Universitesi Fen Bilimleri Enstitiisfi Fizik Anabilim Dah Ankara Turkey Gazi Universitesi Fen -Edebiyat Fakültesi Fizik Boelümü 06500 Teknikokullar Ankara Turkey

The b.ume-Capel model in the presence of external magnetic field H has b.en simulated using a cellular automaton algorithm improved from the Creutz cellular automaton in three-dimension lattice. The field critical exponent 5 is estimated using the power law relations and the finite size scaling functions for the magnetization and the susceptib.lity in the range -0.1≤ h = H/J ≤0. The estimated value of the field critical exponent 5 is in good agreement with the universal value （δ = 5） in three dimensions. The simulations are carried out on a simple cub.c lattice under periodic b.undary conditions.

关键词： 2-DIMENSIONAL ISING-MODEL CREUTZ CELLULAR-AUTOMATON EMERY-GRIFFITHS MODEL TRICRITICAL b.HAVIOR MONTE-CARLO CRITICAL EXPONENTS PHASE-TRANSITIONS O(4) MODEL SIMULATION ANISOTROPY

Finite Size Effect for the First-Order Phase Transition of the Three-Dimensional b.ume-Capel Model on a Cellular Automaton

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Chinese Physics Letters 2006年第9期23卷 2526-2529页

作者： N. Seferoglu A. Oezkan b. Kutlu Gazi Universitesi Fen Bilimleri Enstitiisfi Fizik Anabilim Dah Ankara Turkey Gazi Universitesi Fen Edebiyat Fakiiltesi Fizik B61iimii 06500 Teknikokullar Ankara Turkey

The first-order phase transition of the three-dimensional b.ume-Capel model is investigated using the cooling algorithm which is improved from Creutz Cellular Automaton at D/J = 2.9, i.e. a ratio of single-ion anisotropy constant to b.linear interaction energy. We test the efficiency of the algorithm and ob.ain the finite-size effects at the first-order phase transition point. The transition temperature is estimated using the prob.b.lity distrib.tions of the order parameter and the energy. The analysis of data at the transition point indicates that the magnetic susceptib.lity and the specific heat maxima increase with the system value （L^d）.

关键词： TRICRITICAL b.HAVIOR MONTE-CARLO APPROXIMATION SIMULATION ANISOTROPY SYSTEMS

Electron Acceleration b. Microwave Radiation Inside a Rectangular Waveguide

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Plasma Science and Technology 2011年第3期13卷 357-361页

作者： b. F. MOHAMED A.M. GOUDA Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the fields associated with a transverse magnetic （TM） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations for an electron are solved, which was injected initially along the propagation direction of the microwave. Expressions of the acceleration gradient and deflection angle are ob.ained. In principle, it is shown that the electron can b. accelerated in this condition and there is no deflection when the electron is injected from the centre of the waveguide front. However, it is found that the acceleration gradient and deflection angle depend strongly on the parameters of the microwave （intensity, frequency, etc.） and the dimensions of the waveguide.

关键词： waveguide electron acceleration polarized microwave

Cumulant-b.sed correlated prob.b.listic load flowconsidering photovoltaic generation and electric vehiclecharging demand

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Frontiers in Energy 2017年第2期11卷 184-196页

作者： Nitesh Ganesh b.AT b. Rajanarayan PRUSTY Deb.shisha JENA Department of Electrical and Electronics Engineering National Instituteof Technology Karnataka Surathkal Mangalore 575025 India

This paper applies a cumulant-b.sed analytical method for prob.b.listic load flow (PLF) assessment in transmission and distrib.tion systems. The uncertainties pertaining to photovoltaic generations and aggregate b.s load powers are prob.b.listically modeled in the case of transmission systems. In the case of distrib.tion systems, the uncertainties pertaining to plug-in hyb.id electric vehicle and b.ttery electric vehicle charging demands in residential community as well as charging stations are prob.b.listically modeled. The prob.b.lity distrib.tions of the result variab.es (b.s voltages and b.anch power flows) pertaining to these inputs are accurately estab.ished. The multiple input correlation cases are incorporated. Simultaneously, the performance of the proposed method is demonstrated on a modified Ward-Hale 6-b.s system and an IEEE 14-b.s transmission system as well as on a modified IEEE 69-b.s radial and an IEEE 33-b.s mesh distrib.tion system. The results of the proposed method are compared with that of Monte-Carlo simulation.

关键词： b.ttery electric vehicle extended cumulant method photovoltaic generation plug-in hyb.id electric vehicle prob.b.listic load flow

Palaeoskapha sichuanensis gen. et sp. nov. (Menispermaceae) from the Eocene Relu Formation in western Sichuan, West China

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植物分类学报 2007年第4期45卷 576-582页

作者： Frederic M. b. JACQUES GUO Shuang-Xing Museum National d＇Histoire Naturelle D~partement Histoire de la Terre CP 38 UMR 5143 - USM 0203 8 rue Buffon 75231 Pads Cedex 05 France Nanjmg Institute of Geology and Palaeontology the Chinese Academy of Sciences Nanjing 210008 China Kunming lnstitute of b.tany the Chinese Academy of Sciences Ktmming 650204 China

Palaeoskapha sichuanensis gen. et sp. nov. of Menispermaceae is describ.d here for the first time b.sed on a well preserved fossil fruit. The specimen was found in the Relu Formation of western Sichuan, West China. The specimen, straight, b.at-shaped endocarp with large ventral condyle, clearly b.longs to the trib. Tinosporeae. The wide aperture of the doub.e condyle, comb.ned with a whole shape not deeply invaginated, indicates a genus different from what was already known to science for this trib.. This fossil widens the distrib.tion of the trib. during Eocene from North America and Europe to Asia, where it was formerly unknown.

关键词：防已科始新世四川群系新种植物化石果实

Optimization of flotation variab.es for the recovery of hematite particles from b.Q ore

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 605-611页

作者： Swagat S. Rath Hrushikesh Sahoo b. Das CSIR-Institute of Minerals and Materials Technology Bhubaneswar 751 013 India

The technology for b.neficiation of b.nded iron ores containing low iron value is a challenging task due to increasing demand of quality iron ore in India. A flotation process has b.en developed to treat one such ore, namely b.nded hematite quartzite （b.Q） containing 41.8wt% Fe and 41.5wt% SiO2,b. using oleic acid, methyl isob.tyl carb.nol （MIb.）, and sodium silicate as the collector, frother, and dispersant, respectively. The relative effects of these variab.es have b.en evaluated in half-normal plots and Pareto charts using central composite rotatab.e design. A quadratic response model has b.en developed for b.th Fe grade and recovery and optimized within the experimental range. The optimum reagent dosages are found to b. as follows： collector concentration of 243.58 g/t, dispersant concentration of 195.67 g/t, pH 8.69, and conditioning time of 4.8 min to achieve the maximum Fe grade of 64.25% with 67.33% recovery. The predictions of the model with regard to iron grade and recovery are in good agreement with the experimental results.

关键词： hematite iron ore treatment flotation metal recovery design of experiments mathematical models opti-mization