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An approximate solution of the DKP equation under the hulthén vector potential

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Chinese Physics C 2013年第2期37卷 1-4页

作者： s.Zarrinkamar A.A.Rajabi b.h.Yazarloo h.hassanabadi Department of Physics Shahrood University of Technology

Using the analytical NU technique as well as an acceptable physical approximation to the centrifugal term, the bound-state solutions of the Duffin-Kemmer-Petiau equation are obtained for arbitrary quantum numbers. The solutions appear in terms of the Jacobi Polynomials. Various explanatory figures and tables are included to complete the study.

关键词： Duffin-Kemmer-Petiau equation hulthén potential NU technique

smart computing approach for design and scale-up of conical spouted beds with open-sided draft tubes

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Particuology 2021年第2期19卷 179-190页

作者： M.Karimia b.Vaferi s.h.hosseini M.Olazar s.Rashidi Laboratory of separation and Reaction Engineering(LsRE) Associate Laboratory(LSRE/LCM)Department of Chemical EngineeringFaculty of EngineeringUniversity of PortoRua Dr.Roberto FriasS/N4099-002 PortoPortugal Department of Advanced Calculations ChemicalPetroleumand Polymer Engineering Research CenterShiraz BranchIslamic Azad UniversityShirazIran Department of Chemical Engineering Ilam UniversityIlam 69315-516Iran Department of Chemical Engineering University of the Basque Country UPV/EHUP.O.Box 644E48080 BilbaoSpain Department of Petroleum Engineering Omidiyeh BranchIslamic Azad UniversityOmidiyehIran

Open-sided draft tubes provide an optimal gas distribution through a cross flow pattern between the spout and the annulus in conical spouted *** design,optimization,control,and scale-up of the spouted beds require precise information on operating and peak pressure *** this study,a multi-layer perceptron(MLP)neural network was employed for accurate prediction of these hydrodynamic characteristics.A relatively huge number of experiments were accomplished and the most influential dimensionless groups were extracted using the buckingham-pi ***,the dimensionless groups were used for developing the MLP model for simultaneous estimation of operating and peak pressure *** iterative constructive technique confirmed that 4-14-2 is the best structure for the MLP model in terms of absolute average relative deviation(AARD%),mean square error(MsE),and regression coefficient(R^(2)).The developed MLP approach has an excellent capacity to predict the transformed operating(MsE=0.00039,AARD%=1.30,and R^(2)=0.76099)and peak(MsE=0.22933,AARD%=11.88,and R2=0.89867)pressure drops.

关键词： Conical spouted beds Open-sided draft tubes Operating pressure drops Peak pressure drop smart modeling Design guidelines

Multiple scales method for analyzing a forced damped rotational pendulum oscillatorwithgallows

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Communications in Theoretical Physics 2024年第5期76卷 58-67页

作者： haifa A Alyousef Alvaro h salas b M Alotaibi s A El-Tantawy Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of Mathematics and statistics Universidad Nacional de ColombiaFIZMAKO Research GroupColombia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversityAl-Baha 1988Saudi Arabia

This study reports the analytical solution for a generalized rotational pendulum system with gallows and periodic excited *** multiple scales method(MsM)is applied to solve the proposed *** types of rotational pendulum oscillators are studied and talked about in *** include the forced damped rotating pendulum oscillator with gallows,the damped standard simple pendulum oscillator,and the damped rotating pendulum oscillator without *** MsM first-order approximations for all the cases mentioned are derived in *** obtained results are illustrated with concrete numerical *** first-order MsM approximations are compared to the fourth-order Runge-Kutta(RK4)numerical ***,the maximum error is estimated for the first-order approximations obtained through the MsM,compared to the numerical approximations obtained by the RK4 ***,we conducted a comparative analysis of the outcomes obtained by the used method(MsM)and he-MsM to ascertain their respective levels of *** proposed method can be applied to analyze many strong nonlinear oscillatory equations.

关键词： rotational pendulum system multiple scales method approximate solution damped oscillations forced pendulum with gallows he-multiple scales method

Effect of si Content on Mechanical Properties of a Mo and V Free Low Alloy Cast steel for Automobile Cold Pressing Die

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Journal of Materials science & Technology 2008年第3期24卷 313-316页

作者： b.h.Kim J.s.shin s.M.Lee b.M.Moon h.D.Kim s.Y.Ju O.Y.Choi Advanced Materials R＆D Division Korea Institute of Industrial Technology Incheon 406-840 Korea Tooling Center GM Daewoo Auto ＆ Technology Co. Incheon 403-714 Korea

The effects of si content on combinations of important properties such as hardness, hardenability, and weldability in addition to strength increment were systematically investigated to develop a Mo and V free low alloy cast steel for automobile cold pressing die insert. For the evaluation of the applicability as the die insert, the mechanical properties were measured after spheroidization annealing （sA）, quenching and tempering （Q/T）, and flame hardening （Fh） treatments, respectively. The developed 0.8%-1.6%si containing Mo and V free alloy cast steels showed excellent matrix strengthening effect, hardenability, and weldability, fulfilling the industrial criterion of the mechanical properties for the die insert.

关键词： Low alloy cast steel Cold pressing die Die insert Matrix hardening Flame hardening

Novel insight into dry sliding behavior of Cu-Pb-sn in-situ composite with secondary phase in different morphology

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Journal of Materials science & Technology 2020年第5期40卷 158-167页

作者： b.w.Dong s.h.wang Z.Z.Dong J.C.Jie T.M.wang T.J.Li school of Material science and Engineering Dalian University of TechnologyDalian 116024China

The Cu-24 Pb-x sn(wt%)(x=0,2,4,6)alloys with Pb-rich second-phase particles(sPPs)in different shapes show obviously differently mechanical and self-lubricating *** influence of the sPPs’shape difference on the alloys’mechanical and self-lubricating properties was ***-24 Pb alloy with continuously netty sPPs shows much more intensive stick-slip phenomenon during dry sliding than the other three alloys with independently rodlike *** is mainly due to insufficient lubrication resulted by the netty sPPs’splitting *** the sPPs transforming from netty to rodlike shape under the addition of sn,the stick-slip phenomenon was notably weakened,which was proven to be related to the higher self-lubricating property of alloys with rodlike ***,the simultaneous increase of ductility and tensile strength was observed in the Cu-24 Pb-x sn alloys with increasing sn content,which is because the netty sPPs’splitting behavior will be weakened with them replaced by the rodlike sPPs.

关键词： second-phase particles Netty shape Rodlike shape stick-slip Mechanical property self-lubricating property

Nanotube-based Chemical and biomolecular sensors

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Journal of Materials science & Technology 2008年第4期24卷 578-588页

作者： J.Koh b.Kim s.hong h.Lim h.C.Choi Department of Physics and Astronomy Seoul National University Shillim-Dong Kwanak-Gu Seoul 151-747 Korea Department of Chemistry Pohang University of Science and Technology San 31 Hyoja-Dong Nam-Gu Pohang 790-784 Korea

we present a brief review about recent results regarding carbon nanotube （CNT）-based chemical and biomolecular sensors. For the fabrication of CNT-based sensors, devices containing CNT channels between two metal electrodes are first fabricated usually via chemical vapor deposition （CVD） process or ＂surface programmed assembly＂ method. Then, the CNT surfaces are often functionalized to enhance the selectivity of the sensors. Using this process, highly-sensitive CNT-based sensors can be fabricated for the selective detection of various chemical and biological molecules such as hydrogen, ammonia, carbon monoxide, chlorine gas, DNA, glucose, alcohol, and proteins.

关键词： Chemical vapour deposition Carbon nanotubes sensors biological molecules surface programmed assembly

Fabrication of sAw sensor for Detecting Chemical Agent

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稀有金属材料与工程 2006年第A03期35卷 433-435页

作者： J h Lee b s Joo J s huh D D Lee school of Electronic & Electrical Engineering Kyungpook National UniversityKorea Dept.of Materials science and Metallurgy Kyungpook National UniversityKorea

sAw sensors using five different types of polymer to detect of chemical agents(DMMP,Ch_3CN,Ch_2Cl_2,DCP) have been fabricated and its gas response characteristics were extensively *** polymers used as the sensing material are polyisobutylene(PIb),polyepichlorohydrin(PECh),polydimethylsiloxane(PDMs),polyisoprene(PIP)and polybutadiene(PbD).Their thin films were coated on quartz substrate by spin coating *** types of simulants gases,dimethylmethylphosphonate(DMMP),acetonitrile(Ch_3CN)and dichloromethane(Ch_2Cl_2),dichloropentane(DCP)were used as target gases,instead of the real nerve,blood,choking and vesicant *** spin coating of PIb and PECh,the substrates were heated to 65℃with N_2 flow for 1 h to remove the cyclohexane and ethylacetate which was used as solvent. PDMs was heated to 75℃with N_2 flow for 2 h to remove the ethylacetate which was used as *** and PIP on the substrate were heated to 60℃with N_2 flow for 1 h to remove the benzen which was used as *** sensing characteristics of the sAw sensors were measured by using E-5061A network analyzer.

关键词： sAw DMMP Ch3CN Ch2Cl2 DCP polymer film

Improving cyclic oxidation resistance of Ni_(3)Al-based single crystal superalloy with low-diffusion platinum-modified aluminide coating

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Journal of Materials science & Technology 2020年第19期54卷 132-143页

作者： h.Liu M.M.Xu s.Li Z.b.bao s.L.Zhu F.h.wang Institute of Metal Research Chinese Academy of SciencesWencui Road 62#Shenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaJinzhai Road 96#Hefei 230026China shenyang National Laboratory for Materials science Northeastern UniversityWenhua Road 3#Shenyang 110819China

A low-diffusion Ni Re Pt Al coating((Ni,Pt)Al outer layer in addition to a Re-rich diffusion barrier layer)was prepared on a Ni_(3)Al-base single crystal(sC)superalloy via electroplating and gaseous aluminizing treatments,wherein the electroplating procedures consisted of the composite deposition of Ni-Re followed by electroplating of *** order to perform a comparison with conventional Ni Al and(Ni,Pt)Al coatings,the cyclic oxidation performance of the Ni Re Pt Al coating was evaluated at 1100 and 1150℃.we observed that the oxidation resistance of the Ni Re Pt Al coating was significantly improved by the greater presence of the residualβ-Ni Al phase in the outer layer and the lesser outward-diffusion of Mo from the *** addition,the coating with the Re-rich diffusion barrier demonstrated a lower extent of interdiffusion into the substrate,where the thickness of the second reaction zone(sRZ)in the substrate alloy decreased by 25%.The mechanisms responsible for improving the oxidation resistance and decreasing the extent of sRZ formation are discussed,in which a particular attention is paid to the inhibition of the outward diffusion of Mo by the Re-based diffusion barrier.

关键词： Ni_(3)Al-base superalloy Pt-modified aluminide coating Re-rich diffusion barrier Cyclic oxidation Interdiffusion second reaction zone

wildland fires and moist deciduous forests of Chhattisgarh, India: divergent component assessment

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Journal of Forestry Research 2014年第4期25卷 857-866页

作者： b.h.Kittur s.L.swamy s.s.bargali Manoj Kumar Jhariya Department of silviculture & Agroforestry College of Forestry Kerala Agriculture University Vellanikara Thrissure Kerala India Department of Forestry College of Agriculture Indira Gandhi Krishi Vishwavidyalaya Raipur (C.G.) 492006 India Department of botany DSB Campus Kumaun University Nainital–263001 (Uttarakhand) India

we studied moist deciduous forests of Chhattisgarh, India （1） to assess the effect of four levels of historic wildland fire frequency （high, medium, low, and no-fire） on regeneration of seedlings in fire affected areas during pre and post-fire seasons, （2） to evaluate vegetation struc- ture and diversity by layer in the four fire frequency zones, （3） to evalu- ate the impact of fire frequency on the structure of economically impor- tant tree species of the region, and （4） to quantify fuel loads by fire fre- quency level. we classified fire-affected areas into high, medium, low, and no-fire frequency classes based on government records. Tree species were unevenly distributed across fire frequency categories. shrub density was maximum in zones of high fire frequency and minimum in low- frequency and no-fire zones. Lower tree density after fires indicated that regeneration of seedlings was reduced by fire. The population structure in the high-frequency zone was comprised of seedlings of size class （A） and saplings of size class （b）, represented by Diospyros melanoxylon, Dalbergia sissoo, shorea robusta and Tectona grandis. Younger and older trees were more abundant for Tectona grandis and Dalbargia sis- soo after fire, whereas intermediate-aged trees were more abundant pre- fire, indicating that the latter age-class was thinned by the catastrophic effect of fire. The major contributing components of fuel load included duff litter and small woody branches and twigs on the forest floor. Total fuel load on the forest floor ranged from 2.2 to 3.38 Mg/ha. The netchange in fuel load was positive in high- and medium-frequency fire zones and negative under low- and no-fire zones. Repeated fires, how- ever, slowly reduced stand stability. An ecological approach is needed for fire management to restore the no-fire spatial and temporal structure of moist deciduous forests, their species composition and fuel loads. The management approach should incorporate participatory forest ma

关键词： forest fire diversity fuel load vegetation structure