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Analytical and approximate solutions of nonlinear schrödinger equation with higher dimension in the anomalous dispersion regime

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Journal of Ocean Engineering and science 2022年第2期7卷 143-154页

作者： Lanre Akinyemi Mehmet senol M.s.Osman Department of Mathematics Lafayette CollegeEastonPAUSA Nev¸s ehir HacıBekta¸s Veli University Department of MathematicsNev¸s ehirTurkey Department of Mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt

The generalized Riccati equation mapping method(GREMM)is used in this paper to obtain different types of soliton solutions for nonlinear schrödinger equation with higher dimension that existed in the regimes of anomalous ***,we use the q-homotopy analysis method combined with the Laplace transform(q-HATM)to obtain approximate solutions of the bright and dark optical *** q-HATM illustrates the solutions as a rapid convergent *** addition,to show the physical behavior of the solutions obtained by the proposed techniques,the graphical representation has been provided with some parameter *** findings demonstrate that the proposed techniques are useful,efficient and reliable mathematical method for the extraction of soliton solutions.

关键词： q-homotopy analysis method Generalized Riccati equation mapping method Laplace transform

A Finite and Instantaneous screw Based Approach for Topology Design and Kinematic Analysis of 5-Axis Parallel Kinematic Machines

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 66-75页

作者： Tao sun shuo-Fei Yang Tian Huang Jian s.Dai Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University school of Engineering The University of Warwick Centre for Robotics Research School of Natural Sciences and Mathematics King’s College London University of London

Unifying the models for topology design and kinematic analysis has long been a desire for the research of parallel kinematic machines(PKMs). This requires that analytical description, formulation and operation for both finite and instantaneous motions are performed by the same mathematical tool. Based upon finite and instantaneous screw theory, a unified and systematic approach for topology design and kinematic analysis of PKMs is proposed in this paper. Using the derivative mapping between finite and instantaneous screws built in the authors’ previous work, the finite and instantaneous motions of PKMs are analytically described by the simple and non?redundant screws in quasi?vector and vector forms. And topological and parametric models of PKMs are algebraically formulated and related. These related topological and parametric models are ready to do type synthesis and kinematic analysis of PKMs under the unified framework of screw theory. In order to show the validity of the proposed approach, a kind of two?translational and three?rotational(2T3R)5?axis PKMs is taken as example. Numerous new structures of the 2T3R PKMs are synthe?sized as the results of topology design, and their Jacobian matrix is obtained easily for parameter optimization and performance evaluation. some of the synthesized PKMs have outstanding capabilities in terms of large workspaces and flexible orientations, and have great potential for industrial applications of machining and manufacture. Among them, METROM PKM is a typical example which has attracted a lot of attention from global companies and already been developed as commercial products. The approach is a general and unified approach that can be used in the innovative design of different kinds of PKMs.

关键词： Innovative design Parallel kinematic machines screw theory Finite screw Instantaneous screw

Novel kinetic model for the simulation analysis of the butanol productivity of Clostridium acetobutylicum ATCC 824 under different reactor configurations

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Chinese Journal of Chemical Engineering 2018年第4期26卷 812-821页

作者： Hugo I.Velázquez-sánchez Ricardo Aguilar-López Center of Research and Advances studies of the National Polytechnic Institute (CINVEsTAV) Biotechnology and Bioengineering DepartmentAv. National Polytechnic Institute 2508 Col. San Pedro Zacatenco

Acetone–butanol–ethanol(ABE)fermentation process can be exploited for the generation of butanol as biofuel,however it does need to overcome its low volumetric solvent productivity before it can commercially compete with fossil fuel *** this regard,mathematical modelling and simulation analysis are tools that can serve as the base for process engineering development of biological *** this work,a novel phenomenological kinetic model of Clostridium acetobutylicum ATCC 824 was considered as a benchmark system to evaluate the behaviour of an ABE fermentation under different process configurations using both free and immobilized cells:single stage batch operation,fed-batch,single stage Continuous stirred Tank Reactor(CsTR)and multistage CsTRs with and without biomass *** proposed model achieved a linear correlation index r^2=0.9952 and r^2=0.9710 over experimental data for free and immobilized cells *** predicted maximum butanol concentration and productivity obtained were 13.08 g·L^(-1)and 1.9620 g·L^(-1)·h^(-1)respectively,which represents an increase of 1.01%and 990%versus the currently developed industrial scale process reported currently into the *** results provide a reliable platform for the design and optimization of the ABE fermentation system and showcase the adequate predictive nature of the proposed model.

关键词： Biofuels Butanol Clostridium acetobutylicum Mathematical modelling Process configurations

Compton profiles of NiO and TiO_2 obtained from first principles GWA spectral function

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Chinese Physics B 2016年第6期25卷 407-415页

作者： s M Khidzir M F M Halid W A T Wan Abdullah Department of Physics Universiti of Malaya

In this work,we first use momentum density studies to understand strongly correlated electron behavior,which is typically seen in transition metal *** observe that correlated electron behavior as seen in bulk NiO is due to the Fermi break located in the middle of overlapping spectral functions obtained from a GW（G is Green’s function and W is the screened Coulomb interaction） approximation（GWA） calculation while in the case of TiO2 we can see that the origin of the constant momentum distribution in lower momenta is due to a pile up of spectra before the Fermi *** observations are then used to compare our calculated Compton profiles with previous experimental studies of Fukamachi and *** calculations for NiO are observed to follow the same trend as the experimental profile but it is seen to have a wide difference in the case of TiO2 before the Fermi *** ground state momentum densities differ significantly from the quasiparticle momentum density,thus stressing the importance of the quasiparticle wave function as the input for the study of charge density and the electron localization *** we perform a calculation of the quasiparticle renormalization function,giving a quantitative description of the discontinuity of the GWA momentum density.

关键词： elastic and Compton scattering density functional theory local density approximation gradient and other corrections elements oxides nitrides borides carbides chalcogenides

A New Process for Titanium Aluminides Production from TiO_2

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Journal of Materials science & Technology 2007年第3期23卷 367-372页

作者： A.R.Kamali H.Razavizadeh s.M.M.Hadavi Department of Materials and Metallurgy Engineering IUsT University Department of Chemical and Materials Engineering Maleke Ashtar University

This paper describes a new process for producing titanium aluminides, in particular TiAl, from TiO2 raw material. On the basis of obtained results, the non-completed reaction of TiO2 with Al and Ca in a special reaction vessel results in the production of granulates of titanium aluminides especially Ti3Al and other Ti- Al phases as the metallic product and Ca12Al14O33 as the non-metallic product. By adding KClO4 in the mixture, a nearly completed reaction can be carried out. The products of this reaction are titanium aluminide particularly TiAl as the metallic part and CaAl4O7 （grossite） as the non-metallic slag part. Both product and slag are produced in a separated form. This process, called KRH-method is described in this article. The scanning electron microscopic microstructure of metallic part of the product shows different phases： the matrix phase is TiAI, where the needle form precipitation is TiAl2 and the plate form precipitation includes TiAI and Ti3Al phases. The microstructure of the remelted metallic part indicates dendritic phase with a lamellar structure comprising of TiAl and Ti3Al phases. The interdendritic phase of TiAI is also seen.

关键词： Titanium aluminide Titanium dioxide Grossite KRH process

Analysis and formulation of spur gear stresses with different tip modifications

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Journal of Central south University 2019年第9期26卷 2368-2378页

作者： A.MAPER s.KARUPPANAN s.s.PATIL Department of Mechanical Engineering Universiti Teknologi PETRONASBandar Seri Iskandar 32610Perak Darul RidzuanMalaysia Department of Mechanical Engineering Manipal University JaipurJaipur 303007RajasthanIndia

spur gears are widely used in the power transmission mechanism of several *** to the transmitted torque,spur gears experience high stresses which could cause gear tooth failure by surface pitting or root *** relief and other gear profile modification have been considered for reducing the induced stresses in the gear *** this work,the influence of tip relief on stresses on a pair of identical spur gear was analyzed using commercial FEA software ANsYs,and formulae for estimating contact and bending stresses were *** cases of gear sets were analyzed;a non-modified pair and another two sets with linear and parabolic tip relief *** non-modified gear set frictionless contact stress was validated against the calculated AGMA pitting resistance,Hertzian contact stress and a reported contact stress value in the *** four methods agreed well with each ***,bending stress was also compared with the AGMA bending strength and Lewis bending stress for ***,friction coefficient was varied from 0.0 to 0.3 with increment of *** gear contact stress increased up to 11%relative to the frictionless case,whereas bending stress decreased by 6%.Linear tip relief modification was carried out for increasing normalised tip relief values of 0.25 to 1.0 with increment of *** gear frictionless contact and bending stresses decreased by a maximum of 4%and 2%,*** contact stress increased by up to 7.1%and the bending stress is almost identical with the frictionless *** tip relief was also carried out with similar normalised tip relief *** contact stress decreased by 5%while frictional contact stress increased by up to 11.5%and the bending stress is also almost identical with the frictionless ***,four formulae were introduced for estimating the contact and bending stresses for a tip modified spur gear.

关键词： gear stresses friction linear tip relief parabolic tip relief

Development of magnesium composite alloy by a new method combining B_2O_3 addition and melt stirring

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中国有色金属学会会刊：英文版 2006年第A3期16卷 1870-1874页

作者：卜乐平 s.TANAKA M.TsUsHIDA s.ANDO H.TONDA Graduate school of science and Technology Kumamoto University2-39-1 KurokamiKumamoto 860-8555Japan Machinery and Electronic Engineering Institute Inner Mongolia University of AgricultureHohhot 010018China Department of Materials science and Engineering Faculty of EngineeringKumamoto University2-39-1 KurokamiKumamoto 860-8555Japan

For developing high performance magnesium alloys, a new method in combination of B2O3 addition and melt stirring was applied. When 0, 3%, 6% and 12%( mass fraction) B2O3 was added into pure Mg, many twins were produced in each alloy. The average grain size of Mg was about 200μm. In Mg-6Al alloy, the grain size is decreased from 50 to 35μm by B2O3 addition. In Mg-6RE (rare earth) alloys, the grain size is decreased from 35 to 15μm. The grain size of Mg-9Al- 6Ti-3B2O3 alloy is about 5μm. The hardness of pure Mg does not change by B2O3 addition. In Mg-6Al alloy, the hardness is increased by addition of 3% B2O3, however, the hardness of Mg-6RE alloy is decreased by B2O3 addition. Addition of B2O3 into Mg-Al, Mg-RE and Mg-Al-Ti alloys makes the fine grain structures, the hardness of Mg-RE alloy is decreased. This strange behavior may be interpreted with existence of many fine pores in the alloy. The mechanical properties of composite Mg-9Al-6Ti with 3%B2O3 are higher than those of AZ91C. The present results demonstrate the potential of this new method for developing high performance magnesium alloys.

关键词：镁合金金属熔炼有色金属金属加工

Enthalpy of formation of quasicrystalline phase and ternary solid solutions in the Al-Fe-Cu system

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Rare Metals 2006年第5期25卷 608-613页

作者： I.A.Tomilin s.D.Kaloshkin V.V.Tcherdyntsev Moscow state Institute of steel and Alloys (Technologycal University) 119049 Leninsky prosp.4MoscowRussia

standard enthalpies of formation of quasicrystalline phase and the ternary solid solutions in the Al-Fe-Cu system and the intermetaUic compound FeAI were determined by the means of solution calorimetry. The quasicrystalline phase was prepared using two different methods. The first method （I） consisted of ball milling the mixture of powders of pure aluminum copper and iron in a planetary mill with subsequent compacting by hot pressing and annealing. The second method （Ⅱ） consisted of arc melting of the components in argon atmosphere followed by annealing. The latter method was used for preparing the compound FeAl and the solid solutions. The phases were identified using the XRD method. The enthalpy of the formation was determined for the quasicrystalline phase of the composition Al62Cu25.5Fe12.5 and the temary BCC solid solutions Al35Cu14Fe51, Al40Cu17Fe43, and Al50.4Cu19.6Fe30. The measured enthalpy of formation of the intermetallic compound FeAl is in good agreement with the earlier published data. The enthalpies of formation of the quasicrystalline phases prepared using two different methods are close to each other, namely, -22.7±3.4 （method I） and -21.3±2.1 （method Ⅱ） kJ/mol.

关键词： enthalpy of formation calorimetry quasicrystals Al-Fe-Cu

Wien Effect in suspensions of Electrodialyzed soil Particles and Its Influencing Factors

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Pedosphere 2002年第3期12卷 235-242页

作者： LICHENGBAO s.P.FRIEDMAN 等 Instituteofsoilscience theChineseAcademyofSciencesP.O.Box821Nanjing210008（China） Instituteofsoil WaterandEnvironmentalSciencesAgriculturalResearchOrganizationtheVolcaniCenterBe

The electrical conductivity of suspensions and their supernatants from theelectrodialyzed clay fractions of latosol, yellow-brown soil and black soil equilibrated withnitrate solutions were determined at different field strengths using a short high-voltage pulseapparatus to demonstrate the Wien effect in soil suspensions and to investigate factors affectingit. It was found that Wien effect was much stronger in suspensions with a clay content of 30 gkg^(-1) from the soils equilibrated with a 1 X 10^(-4) KNO_3 solution than in their *** threshold field strength (TFs), at which the relative conductivity is equal to 1.05, i.e., theWien effect begins to be obvious, of the yellow-brown soil suspensions (clay content of 30 gkg^(-1)) equilibrated with different nitrate solutions of a concentration of 1 X 10^(-4)/z molL^(-1), where z is the valence, varied with the type of nitrates, being lowest for NaNO_3 (47 kVcm^(-1)) and highest for Ca(NO_3)_2 (98 kV cm^(-1)). At high field strengths (larger than 130 kVcm^(-1)), the relative conductivities of yellow-brown soil suspensions containing different nitratesdiminished in the order: NaNO_3 > KNO_3 > Mg(NO_3)_2 > Zn(NO_3)_2 > Ca(NO_3)_2. The rates andintensities of the Wien effect in the suspensions of the three soils equilibrated with 5 X 10^(-5)mol L^(-1) Ca(NO_3)_2 solution were in the order of the yellow-brown soil > the latosol > the blacksoil. The results for the yellow-brown soil suspensions (clay concentration of 30 g kg )equilibrated with KNO_3 solutions of various concentrations clearly demonstrated that the moredilute the solution, the lower the TFs, and the larger the relative conductivity of the suspensionsat high field strengths. The results for yellow-brown soil suspensions with different clayconcentrations indicated that as the clay concentration increased, the low field electricalconductivity, EC_0, also increased, but the TFs decreased, and the Wien effect increased.

关键词： electrical conductivity high field strength soil suspension wien effect