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On SOME MODEL DIFFUSIOn PROBLEMS WITh A nOnLOCAL LOWER ORDER TERM

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Chinese Annals of Mathematics,Series B 2003年第2期24卷 147-166页

作者： n.h.ChAnG M.ChIPOT Academia Sinica Institute of MathematicsTaipei 11 529Taiwan China.Institut fur MathematikAbt.Angewandte MathematikUniversitat Zurich Winterthurerstrasse 190CH-8057 ZurichSwitzerland.

The authors consider a class of nonlinear parabolic problems where the lower order term isdepending on a weighted integral of the solution, and address the issues of existence, uniqueness,stationary solutions and in s... 详细信息

关键词： nonlocal problems Elliptic equations Parabolic equations Asymptotic behaviour Stationary problems

nUMERICAL SIMULATIOnS FOR A VARIABLE ORDER FRACTIOnAL CABLE EQUATIOn

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Acta Mathematica Scientia 2018年第2期38卷 580-590页

作者： A.M.nAGY n.h.SWEILAM Department of Mathematics Faculty of Science Benha University Department of Mathematics Faculty of Science Cairo University

In this article, Crank-nicolson method is used to study the variable order fractional cable equation. The variable order fractional derivatives are described in the Riemann- Liouville and the Griinwald-Letnikov sense. The stability analysis of the proposed technique is discussed. numerical results are provided and compared with exact solutions to show the accuracy of the proposed technique.

关键词： Crank-nicolson method variable order fractional cable equation stability anal-ysis

Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines

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Frontiers of Chemical Science and Engineering 2013年第4期7卷 415-421页

作者： Rekha M. Kathyayini h nagaraju n Catalysis Research Laboratory St Joseph's College Post Graduate and Research Centre Bangalore 560027 India Centre for Emerging Technologies Global Campus Jain University Bangalore 562112 India

Two catalysts, alumina and manganese oxide supported on alumina, have been prepared by calcination and precipitation-impregnation methods, respectively. The catalysts are characterised by the following techniques： Brunner-Emmett-Teller-n2 adsorption-desorption for sur- face area, temperature programmed desorption of nh3 and n-butyl amine back titration methods for surface acidity, powder X-ray diffraction for textural properties, and Fourier transform infrared spectroscopy for the anionic radicals. The catalytic activity has been determined under heterogeneous conditions in the condensation reaction between o-phenylenediamine and benzil. The product purity is checked by thin-layer chromatography and melting point. The products are also analysed by LC-MS and 1h-nMR techniques. The yields of the products have been found to be good and catalysts exhibited excellent recyclability. The effect of changing the reaction para- meters such as temperature, reaction time, amount of the catalyst, nature of solvent and molar ratio of reactants on the yield of the product has been studied. The surface acidity of the catalysts plays an important role in activating the reaction.

关键词： alumina manganese oxide deposited onalumina quinoxaline synthesis

Simple Metrics for Representing East Asian Winter Monsoon Variability:Urals Blocking and Western Pacific Teleconnection Patterns

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Advances in Atmospheric Sciences 2016年第6期33卷 695-705页

作者： hoffman h.n.ChEUnG Wen ZhOU Guy Carpenter Asia-Pacific Climate Impact Centre School of Energy and EnvironmentCity University of Hong KongHong Kong SAR City University of hong Kong Shenzhen Research Institute Shenzhen 518057

Instead of conventional East Asian winter monsoon indices （EAWMIs）, we simply use two large-scale teleconnection patterns to represent long-term variations in the EAWM. First, the Urals blocking pattern index （UBI） is closely related to cold air advection from the high latitudes towards western Siberia, such that it shows an implicit linkage with the Siberian high intensity and the surface air temperature （SAT） variations north of 40°n in the EAWM region. Second, the well-known western Pacific teleconnection index （WPI） is connected with the meridional displacement of the East Asian jet stream and the East Asian trough. This is strongly related to the SAT variations in the coastal area south of 40°n in the EAWM region. The temperature variation in the EAWM region is also represented by the two dominant temperature modes, which are called the northern temperature mode （nTM） and the southern temperature mode （STM）. Compared to 19 existing EAWMIs and other well-known teleconnection patterns, the UBI shows the strongest correlation with the nTM, while the WPI shows an equally strong correlation with the STM as four EAWMIs. The UBI-nTM and WPI-STM relationships are robust when the correlation analysis is repeated by （1） the 31-year running correlation and （2） the 8-year high-pass and low-pass filter. hence, these results are useful for analyzing the large-scale teleconnections of the EAWM and for evaluating this issue in climate models. Int particular, more studies should focus on the teleconnection patterns over extratropical Eurasia.

关键词： East Asian winter monsoon Urals blocking high western Pacific teleconnection pattern teleconnection

Effect of Tin Incorporation on Thermo-Mechanical Properties of Glassy Se80Te20 Alloy

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Chinese Physics Letters 2014年第3期31卷 115-117页

作者： h. Kumar A. Sharma n. Mehta Department of Physics Banaras Hindu University Varanasi 221005 India

We report an analysis on the hardness behavior of glassy Se80？xTe20Snx alloy. The crucial thermo-mechanical parameters （micro-hardness, volume and formation energy of micro-voids and the modulus of elasticity） are examined. The results indicate that the thermo-mechanical parameters are changed significantly after incorporation of Sn in glassy Se80Te20 alloy.

关键词： ALLOYS RESEARCh hARDnESS ThERMOMEChAnICAL treatment GLASS -- Research PhYSICS research

Multilayer transition in a spin-1 Blume Capel model with RKKY interaction and quantum transverse anisotropy

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Chinese Physics B 2011年第1期20卷 609-615页

作者： n.Tahiri h.Ez-Zahraouy A.Benyoussef Computational Physics Group LMPHEDepartement de PhysiqueFaculte des SciencesUniversite Mohammed V-AgdalB.P.1014RabatMorocco

Using mean-field theory, we have studied the effect of quantum transverse anisotropies with RKKY interaction on the multi-layer transition and magnetic properties of the spin-1 Blume-Capel model of a system formed by two magnetic multi-layer materials, of different thicknesses, separated by a non-magnetic spacer of thickness M. It is found that the multilayer magnetic order-disorder transition temperature depends strongly on the value of the transverse anisotropy. The multilayer transition temperature decreases when increasing the transverse anisotropy. Furthermore, there exists a critical quantum transverse anisotropy △xL beyond which the separate transitions occur in the two magnetic layers. The critical transverse anisotropy AxL decreases （increases） on increasing the non-magnetic spacer of thickness M （on increasing the crystal field）, and AxL undergoes oscillations as a function of the Fermi level.

关键词： quantum transverse anisotropy order-disorder lavering transitions. RKKY interaction

Understanding association between methylene blue dye and biosorbent: Palmyrah sprout casing in adsorption process in aqueous phase

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Water Science and Engineering 2023年第2期16卷 154-164页

作者： D.M.n.h.Jayasuriya Kannan nadarajah Department of Agricultural Engineering Faculty of AgricultureUniversity of JaffnaAriviyal NagarKilinochchi 44000Sri Lanka

Water pollution caused by industrial dyes has become a severe problem in the modern world. Biosorbents can be used in an eco-friendly manner to remove industrial dyes. In this study, five biosorbents were selected: palmyrah sprout casing (PSC), manioc peel, lime peel, king coconut husk, and coconut kernel. Batch adsorption experiments were conducted to identify the best biosorbent with the highest ability to adsorb methylene blue (MB) from wastewater. The detailed mechanisms of PSC used in the adsorptive removal of MB in aqueous phase were investigated. Of the five biosorbents, PSC exhibited the best removal performance with an adsorption capacity at equilibrium (qe) of 27.67 mg/g. The qe values of lime peel, king coconut husk, manioc peel, and coconut kernel were 24.25 mg/g, 15.29 mg/g, 10.84 mg/g, and 7.06 mg/g, respectively. To explain the mechanisms of MB adsorption with the selected biosorbents, the Fourier transform infrared (FTIR) spectrometry and X-ray diffraction (XRD) analyses were performed to characterize functional properties, and isotherm, kinetic, rate-limiting, and thermodynamic analyses were conducted. The FTIR analysis revealed that different biosorbents had different functional properties on their adsorptive surfaces. The FTIR and XRD results obtained before and after MB adsorption with PSC indicated that the surface functional groups of carbonyl and hydroxyl actively participated in the removal process. According to the isotherm analysis, monolayer adsorption was observed with the Langmuir model with a determination coefficient of 0.998. The duration to reach the maximum adsorption capacity for MB adsorption with PSC was 120 min, and the adsorption process was exothermic due to the negative enthalpy change (-9.950 kJ/mol). Moreover, the boundary layer thickness and intraparticle diffusion were the rate-limiting factors in the adsorption process. As a new biosorbent for MB adsorption, PSC could be used in activated carbon production to enhance the

关键词： Biosorbents Isotherm Kinetics Methylene blue Rate-limiting factor Thermodynamics

Minimal Length Quantum Mechanics of Dirac Particles in noncommutative Space

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Chinese Physics Letters 2015年第3期32卷 1-4页

作者： A. n. Ikot h. P. Obong h. hassanabadi Theoretical Physics Group Department of Physics University of Port Harcourt Choba PMB 5323 Nigeria Department of Basic Sciences Shahrood Branch Islamic Azad University Shahrood Iran

We study the two-dimensional harmonic oscillator in commutative and noncommutative space within the framework of minimal length quantum mechanics for spin-l^2 particles. The energy spectra and the eigenfunction are ob... 详细信息

关键词： length nC Minimal Length Quantum Mechanics of Dirac Particles in noncommutative Space GUP Planck

Analysis of global momentum transfer due to buried mine detonation

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Defence Technology（防务技术） 2019年第5期15卷 821-827页

作者： n.heider V.Denefeld h.Aurich Ernst-Mach-Institute

The emergence of improvised explosive devices (IED) significantly extended the spectrum of possiblethreat mechanisms to military vehicles and their occupants. Especially buried high explosive (hE)charges lead to new and originally not investigated loading conditions during their detonation. It is theinteraction of the embedding geomaterial with the detonation products that leads to a strongly increasedglobal impulse transfer on the vehicle with following high accelerations on the vehicle occupant. Thispaper presents a comprehensive approach for the analysis of occupant loading. In a first step, we presentthe so called ring technology which allows the experimental determination of the locally resolvedspecific impulse distribution on a vehicle floor due to buried charge detonation. A complementarymethod is the use of scaled model vehicles that allows the determination of global vehicle loading parameterssuch as jump height or vehicle accelerations. Both techniques were used to study the influenceof burial conditions as burial depth, embedding material or water content on the impulse transfer ontothe vehicle. These experimental data are used to validate material models for the embedding sand orgravel materials. This validated material description is the basis for numerical simulation models used inthe assessment of occupant safety. In the last step, we present a simulation model for a generic militaryvehicle including a hybrid III occupant dummy that is used for the determination of biomechanicaloccupant exposure levels. Typical occupant loadings are evaluated and correlated with burial conditionsas hE mass and global momentum transfer.

关键词： Improvised explosive device Vehicle protection Occupant loading