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Applied mathematics and mechanics(English Edition) 2024年第2期45卷 373-388页

作者： m.RAHmAN m.TURKYILmAzOGLU z.mUSHTAQ Department of mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan Department of mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity *** system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c mATLAB *** outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower *** the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom *** ranges of various parameters taken into account are Pr=6.2,Re=2,m=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number

Flow of Eyring-Powell liquid due to oscillatory stretchable curved sheet with modified Fourier and Fick’s model

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Applied mathematics and mechanics(English Edition) 2021年第10期42卷 1461-1478页

作者： m.ImRAN z.ABBAS m.NAVEED Department of mathematics The Islamia University of BahawalpurBahawalpur 63100Pakistan Department of mathematics Khwaja Fareed University of Engineering&Information TechnologyRahim Yar Khan 64200Pakistan

This study deals with the features of the mass and heat transport mechanism by adopting a modified version of Fourier and Fick’s model known as the CattaneoChristov double diffusive *** time-dependent magnetohydrodynamic(mHD)flow of the Eyring-Powell liquid across an oscillatory stretchable curved sheet in the presence of Fourier and Fick’s model is *** acquired set of flow equations is transformed into the form of nonlinear partial differential equations(PDEs)by applying appropriate similarity variables.A convergent series solution to the developed nonlinear equations is accomplished with the help of an analytical approach,i.e.,the homotopy analysis method(HAm).The consequences of diverse parameters,including the dimensionless EyringPowell liquid parameter,the radius of curvature,the Schmidt/Prandtl numbers,the ratio of the oscillatory frequency of the sheet to its stretchable rate constant,the mass and thermal relaxation variables involved in the flow,and the heat and mass properties,are displayed through graphs and *** is noted from this study that the amplitude of the pressure distribution rises for the high parametric values of the Eyring-Powell parameter.

关键词： oscillatory stretchable curved surface magnetohydrodynamic(mHD) Eyring-Powell liquid Cattaneo-Christov double diffusion analytical technique

Preliminary performance analysis and optimization based on 1D neutronics model for Indian DEmO HCCB blanket

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Plasma Science and Technology 2020年第8期22卷 184-191页

作者： D AGGARWAL C DANANI m z YOUSSEF Institute for Plasma Research GandhinagarGujarat 382428India Homi Bhabha National Institute(HBNI) AnushaktinagarMumbai 400094India University of California-Los Angeles Los AngelesCA 90095United States of America

India,under its breeding blanket R&D program for DEmO,is focusing on the development of two tritium breeding blanket concepts;namely the lead-lithium-cooled ceramic breeder and the helium-cooled ceramic breeder(HCCB).The study presented in this paper focuses on the neutronic design analysis and optimization from the tritium breeding perspective of the HCCB *** Indian concept has an edge-on configuration and is one of the variants of the helium-cooled solid breeder blanket concepts proposed by several partner countries in *** Indian HCCB blanket having lithium titanate(Li2TiO3)as the tritium breeder and beryllium(Be)as the neutron multiplier with reduced-activation ferritic/martensitic steel structure aims at utilizing the low-energy neutrons at the rear part of the *** aim of the optimization study is to minimize the radial blanket thickness while ensuring tritium self-sufficiency and provide data for further neutronic design and thermal-hydraulic layout of the HCCB *** is found that inboard and outboard blanket thicknesses of 40 cm and 60 cm,respectively,can give a tritium breeding ratio(TBR)>1.3,with 60%6Li enrichment,which is assumed to be sufficient to cover potential tritium losses and associated *** results also demonstrated that the Be packing fraction(PF)has a more profound impact on the TBR as compared to 6Li enrichment and the PF of Li2TiO3.

关键词： DEmO helium-cooled ceramic breeder blanket neutronic optimization study tritium breeding ratio

Antioxidative Responses and metal Accumulation in Invasive Plant Species Growing on mine Tailings in zanjan, Iran

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Pedosphere 2011年第6期21卷 802-812页

作者： m.m.A.BOOJAR z.TAVAKKOLI Department of Biology Tarbiat Moalem University

Tailings of a Pb and zn mine as a metal-contaminated area （zone 1） with two pioneer plant species, Peganum harmala and zygophyllum fabago, were investigated and compared with a non-contaminated area （zone 2） in the vicinity. Total concentrations of Pb, zn, and Cu in the soil of zone 1 were 1 416, 2 217, and 426 mg kg-1, respectively, and all exceeded their ranges in the normal soils. The soil pH was in the neutral range and most of the physical and chemical characteristics of the soils from both zones were almost similar. The species z. fabago accumulated higher Cu and zn in its aerial part and roots than the normal plants. On the other hand, their concentrations did not reach the criteria that the species could be considered as a metal hyperaccumulator. The species P. harmala did not absorb metals in its roots; accordingly, the accumulation factor values of these metals were lower than 1. The contents of chlorophyll, biomass, malondialdehyde, and dityrosine in these two species did not vary significantly between the two zones studied. In zone 1, leaf vacuoles of z. fabago stored 35.6% and 43.2% of the total leaf Cu and zn, respectively. However, in this species, the levels of phytochelatins （PCs） and glutathione （GSH） and antioxidant enzyme activities were significantly higher in zone 1 than in zone 2. In conclusion, metal exclusion in P. harmala and metal accumulation in z. fabago were the basic strategies in the two studied pioneer species growing on the metal-contaminated zone. In response to metal stress, elevation in antioxidant enzyme activities, increases in the PCs and GSH levels in the aerial parts, and metal storage within vacuoles counteracted each other in the invasion mechanism of z. ]abago.

关键词： accumulation factor antioxidant enzymes glutathione metal stress phytochelatins

Shearfree Spherically Symmetric Fluid models

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Chinese Physics Letters 2012年第5期29卷 41-44页

作者： m.Sharif z.Yousaf Department of mathematics University of the PunjabQuaid-e-Azam CampusLahore-54590Pakistan

We attempt to discover some exact analytical models of the spherically symmetric spacetime of collapsing fluid under shearfree *** types of solution are considered:one is to impose a condition on the mass function,while the other is to restrict the *** obtain five exact models in total,and some of them satisfy the Darmoie conditions.

关键词： conditions. exact satisfy

Computation of the Fractal Pattern in manganese Dendrites

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Chinese Physics Letters 2005年第8期22卷 2112-2115页

作者： z.merdan m.Bayirli DepartmentofPhysics GaziosmanpasaUniversityTokatTurkey

The images of manganese flowers (clusters) on the surface of the naturalmagnesium silicate substance are scanned and the pictures of them are transferred to computeratmosphere. By using these scanning parameters, the exponents of density correlation function andfractal dimension values are calculated. For all different groups between the least and the mostdense in the samples, the correlation function exponents may range from 0.141 to 0.178 and thefractal dimension values may vary between 1.61 and 1.88. In addition, the manganese flowers aredivided into seven different groups according to their smallest- and largest-density features. Theformation of the natural manganese clusters (flowers, dendrites) on the surface of the magnesiumsilicate substance can be defined by using the deposition, diffusion and aggregation model.

关键词： DIFFUSION-LImITED AGGREGATION mODEL

A prediction model for the effective thermal conductivity of nanofluids considering agglomeration and the radial distribution function of nanoparticles

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Acta mechanica Sinica 2018年第3期34卷 507-514页

作者： z.m.zheng B.Wang School of Physics Sun Yat-Sen UniversityGuangzhou 510275China Instimt Franco-Chinois de l'Energie Nucleaire Sun Yat-Sen UniversityZhuhai 519000China

Conventional heat transfer fluids usually have low thermal conductivity, limiting their efficiency in many applications. many experiments have shown that adding nanosize solid particles to conventional fluids can greatly enhance their thermal conductivity. To explain this anomalous phenomenon, many theoretical investigations have been conducted in recent years. Some of this research has indicated that the particle agglomeration effect that commonly occurs in nanofluids should play an important role in such enhancement of the thermal conductivity, while some have shown that the enhancement of the effective thermal conductivity might be accounted for by the structure of nanofluids, which can be described using the radial distribution function of particles. However, theoretical predictions from these studies are not in very good agreement with experimental results. This paper proposes a prediction model for the effective thermal conductivity of nanofluids, considering both the agglomeration effect and the radial distribution function of nanoparticles. The resulting theoretical predictions for several sets of nanofluids are highly consistent with experimental data.

关键词： Nanofluid Thermal conductivity modeling Agglomeration Radial distribution function

Predicting the response of continuous RC deep beams under varying levels of differential settlement

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 686-700页

作者： m.z.NASER R.A.HAWILEH Glenn Department of Civil Engineering Clemson UniversityClemsonSC 29634USA Department of Civil Engineering American University of SharjahSharjahUnited Arab Emirates materials Science and Engineering Research Institute American University of SharjahSharjahUnited Arab Emirates

This paper investigates the effect of differential support settlement on shear strength and behavior of continuous reinforced concrete(RC)deep beams.A total of twenty three-dimensional nonlinear finite element models were developed taking into account various constitutive laws for concrete material in compression(crushing)and tension(cracking),steel plasticity(i.e.,yielding and strain hardening),bond-slip at the concrete and steel reinforcement interface as well as unique behavior of spring-like support *** models are first validated by comparing numerical predictions in terms of load-deflection response,crack propagation,reaction distribution,and failure mode against that of measured experimental data reported in *** the developed models were successfully validated,a parametric study was designed and *** parametric study examined number of critical parameters such as ratio and spacing of the longitudinal and vertical reinforcement,compressive and tensile strength of concrete,as well as degree(stiffness)and location of support stiffness to induce varying levels of differential *** study also aims at presenting a numerical approach using finite element simulation,supplemented with coherent assumptions,such that engineers,practitioners,and researchers can carry out simple,but yet effective and realistic analysis of RC structural members undergoing differential settlements due to variety of load actions.

关键词： concrete continuous beams deep beams finite element modeling support settlement

Evaluating ultrasound signals of carbon steel fatigue testing using signal analysis approaches

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Journal of Central South University 2014年第1期21卷 232-241页

作者： m.m.Padzi S.Abdullah m.z.Nuawi S.m.Beden z.m.Nopiah Department of mechanical and materials Engineering Universiti Kebangsaan Malaysia

The application of ultrasound techniques to monitor the condition of structures is becoming more prominent because these techniques can detect the early symptoms of defects such as cracks and other *** early detection of defects is of vital importance to avoid major failures with catastrophic *** assessment of an ultrasound technique was used to investigate fatigue damage *** tests were performed according to the ASTm E466-96 standard with the attachment of an ultrasound sensor to the test *** 1045 carbon steel was used due to its wide application in the automotive industry.A fatigue test was performed under constant loading stress at a sampling frequency of 8 *** sets of data acquisition systems were used to collect the fatigue strain signals and ultrasound *** of the signals were edited and analysed using a signal processing *** methods were used to evaluate the signals,the integrated Kurtosis-based algorithm for z-filter technique(I-kaz) and the short-time Fourier transform(STFT).The fatigue damage behaviour was observed from the initial stage until the last stage of the fatigue *** results of the I-kaz coefficient and the STFT spectrum were used to explain and describe the behaviour of the fatigue damage.I-kaz coefficients were ranged from 60 to 61 for strain signals and ranged from 5 to 76 for ultrasound signals.I-kaz values tend to be high at failure point due to high amplitude of respective *** spectrogram displays the colour intensity which represents the damage severity of the strain signals.I-kaz technique is found very useful and capable in assessing both stationary and non-stationary signals while STFT technique is suitable only for non-stationary signals by displaying its spectrogram.

关键词： fatigue ultrasound signal analysis integrated Kurtosis-based algorithm for z-filter technique short-time Fouriertransform

Environmental impact of radionuclide migration in groundwater from a low intermediate level radioactive waste repository

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Journal of Environmental Sciences 2001年第2期13卷 180-184页

作者： J S Wang z F Yang S S Li z m Wang Institute of Environmental Sciences Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875 China.

The radionuclide migration from a certain Chinese repository with low-intermediate level radioactive solid waste is studied. The migration in groundwater is analyzed and computed in detail. Under presumption of normal releasing, or the bottom of the repository has been marinated for one month with precipitation reaching 600 mm once and a 6 m aerated zone exists, a prediction for 7 radionuclides is conducted. It shows that the aerated zone is the primary barrier for migration. The migration for radionuclides 60Co, 137Cs, 90Sr, 63Ni, etc. will be retarded in it within 500 years. The concentration of 239Pu will be decreased by amount of 6 order. Only 3H and 14C can migrate through the aerated zone. The radionuclides that go through the aerated zone and enter the aquifer will exist in spring, stream and sea. Based on this, the intake dose by residents in different age group resulting from drinking contaminated spring water, eating seafood is calculated. The results showed that the impact of the repository to the key resident group is lower than the limit in national repository regulation standard. This complies with the repository management target.

关键词： intermediate level radioactive waste repository Environmental impact of radionuclide migration in groundwater from a low