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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 444-448页

作者： A.K.Chaubey b.b.jha b.K.Mishra Institute of Minerals and Materials Technology (IMMT)

Mg-7.6% Al （in mass fraction） alloy matrix composites reinforced with different volume fractions of nano- crystalline Al3Cas particles were synthesized by powder metallurgy, and the effect of the volume fraction of reinforcement on the mechanical properties was studied. Room temperature compression test reveals considerable improvement on mechanical properties as compared to unreinforced matrix. The compressive strength increases from 683 MPa for unre- inforced alloy matrix to about 767 and 823 MPa for the samples having 20 and 40 vol% of reinforcement, respectively, while retaining appreciable plastic deformation ranging between 12 and 24%. The specific strength of the composites increased significantly, demonstrating the effectiveness of the low-density AlaCas reinforcement.

关键词： Intermetallics Consolidation Dispersion strengthening Powder metallurgy Mechanicalproperty Electron microscopy

Influence of in-flight particle state diagnostics on properties of plasma sprayed YSZ-CeO_(2) nanocomposite coatings

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International Journal of Smart and Nano Materials 2014年第3期5卷 207-216页

作者： S.Mantry b.b.jha A.Mandal D.K.Mishra b.K.Mishra M.Chakraborty CSIR-Institute of Minerals&Materials Technology Bhubaneswar 751013OdishaIndia School of Minerals Metallurgical and Materials EngineeringIndian Institute of Technology BhubaneswarBhubaneswar 751007OdishaIndia Department of Physics Institute of Technical Education and ResearchSiksha‘O’Anusandhan UniversityKhandagiri SquareBhubaneswar 751030OdishaIndia Department of Physics College of ScienceEngineering and TechnologyUniversity of South AfricaJohannesburgSouth Africa

This article describes the influence of controlling in-flight hot particle characteristics on properties of plasma sprayed nanostructured yttria stabilized zirconia(YSZ)*** article depicts dependence of adhesion strength of as-sprayed nanostructured YSZ coatings on particle temperature,velocity and size of the splat prior to impact on the metallic *** temperature measurement is based on two-color pyrometry and particle velocities are measured from the length of the particle traces during known exposure *** microstructure and adhesion strength of as-sprayed nano-YSZ coatings were *** emission scanning electron microscopy results revealed that morphology of coating exhibits bimodal microstructure consisting of nano-zones reinforced in the matrix of fully melted *** coating adhesion strength is noticed to be greatly affected by the melting state of *** adhesion strength of 42.39 MPa has been experimentally found out by selecting optimum levels of particle temperature and *** enhanced bond strength of nano-YSZ coating may be attributed to higher interfacial toughness due to cracks being interrupted by adherent nano-zones.

关键词： CeYSZ nano-zones spray diagnostics adhesion plasma spraying

Time-dependent MHD Couette flow of rotating fluid with Hall and ion-slip currents

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Applied Mathematics and Mechanics(English Edition) 2012年第4期33卷 399-410页

作者： b.K.jha C.A.APERE Department of Mathematics Ahmadu Bello University

The unsteady magnehydrodynamics （MHD） Couette flow of an electrically conducting fluid in a rotating system is investigated by taking the Hall and ion-slip currents into consideration. The derived fundamental equations on the assumption of a small magnetic Reynolds number are solved analytically with the well-known Laplace transform technique. The unified closed-form expressions axe obtained for the velocity and the skin friction in the two different cases of the magnetic field being fixed to either the fluid or the moving plate. The effects of various parameters on the velocity and the skin friction axe discussed by graphs. The results reveal that the primary and secondary velocities increase with the Hall current. An increase in the ion-slip paxameter also leads to an increase in the primary velocity but a decrease in the secondary velocity. It is also shown that the combined effect of the rotation, Hall, and ion-slip parameters determines the contribution of the secondary motion in the fluid flow.

关键词： magnehydrodynamics (MHD) Couette flow rotating system Hall andion-slip currents accelerated motion

Unsteady generalized Couette flow in composite microchannel

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Applied Mathematics and Mechanics(English Edition) 2011年第1期32卷 23-32页

作者： M.L.KAURANGINI b.K.jha Department of Mathematical Sciences Kano University of Science and Technology Department of Mathematics Ahmadu Bello University

A numerical study is reported on the fully developed unsteady laminar fluid flow in microchannel parallel-plates partially filled with a uniform porous medium and partially filled with a clear fluid. The flow is induced by the movement of one of the plates and the pressure gradient. The brinkman-extended Darcy model is utilized to model the flow in the porous region, while the Stokes equation is used in the clear fluid region. A theoretical analysis is also presented for the fully developed steady flow to find closed- form expressions for the interracial velocity and the velocity and skin frictions at the bounding plates. Numerical computations shows excellent agreement between the closedform solutions for fully developed steady flow and the numerical solution to unsteady flow at large values of time.

关键词： unsteady flow composite microchannel

Unsteady natural convection Couette flow of heat generating/absorbing fluid between vertical parallel plates filled with porous material

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Applied Mathematics and Mechanics(English Edition) 2012年第3期33卷 303-314页

作者： b.K.jha M.K.MUSA Department of Mathematics Ahmadu Bello UniversityZaria 234Nigeria Mathematics Unit School of Basic and Remedial StudiesAhmadu Bello UniversityFuntua 6007Nigeria

The extended brinkman Darcy model for momentum equations and an energy equation is used to calculate the unsteady natural convection Couette flow of a viscous incompressible heat generating/absorbing fluid in a vertical channel （formed by two infinite vertical and parallel plates） filled with the fluid-saturated porous medium. The flow is triggered by the asymmetric heating and the accelerated motion of one of the bounding plates. The governing equations are simplified by the reasonable dimensionless parameters and solved analytically by the Laplace transform techniques to obtain the closed form solutions of the velocity and temperature profiles. Then, the skin friction and the rate of heat transfer are consequently derived. It is noticed that, at different sections within the vertical channel, the fluid flow and the temperature profiles increase with time, which are both higher near the moving plate. In particular, increasing the gap between the plates increases the velocity and the temperature of the fluid, however, reduces the skin friction and the rate of heat transfer.

关键词： heat generating/absorbing fluid natural convection flow porous material acceleration motion

Interplay of conducting and non-conducting walls on hydromagnetic natural convection flow in a vertical micro-channel with Hall current

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Propulsion and Power Research 2021年第2期10卷 155-168页

作者： basant K.jha Peter b.Malgwi Department of Mathematics Ahmadu Bello UniversityZariaNigeria Department of Mathematics Air Force Institute of TechnologyKadunaNigeria

Theoretical investigation on the interaction between conducting and nonconducting walls on hydromagnetic natural convection flow of viscous incompressible and electrically conducting fluid through a vertical micro-channel taking into account the effects of induced magnetic field in presence of Hall current is *** coupled equations responsible for the flow are obtained when either the micro-channel walls are electrically conducting or are electrically *** the method of undetermined coefficients,exact solution are obtained and presented in dimensionless form subject to relevant boundary *** for fluid velocity,induced magnetic field,skin friction,volume flow rate and induced current density in both primary and secondary flow directions are also *** of some governing parameters like Hall current parameter,rarefaction parameter and Hartmann number on the different flow situations are given using the aid of line graphs and *** main conclusion of the present analysis is that,in the existence of rarefaction parameter,primary fluid velocity could be enhanced with the increase in Hall parameter when the micro-channel walls are either insulated or when the left micro-channel wall is electrically *** obtained in this work are relevant in many magnetically controlled devices and could also be used as a benchmark in checking the accuracies of result obtained in some empirical experiments.

关键词： Magnetohydrodynamic(MHD) Hall current Micro-channel Velocity slip Temperature jump

A Multi-Conditional Proxy broadcast Re-Encryption Scheme for Sensor Networks

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Computers, Materials & Continua 2020年第12期65卷 2079-2090页

作者： Pang Li Lifeng Zhu brij b.Gupta Sunil Kumar jha Nanjing Vocational College of Information Technology Nanjing210044China State Key Laboratory of bioelectronics Jiangsu Key Laboratory of Remote Measurement and ControlSchool of Instrument Science and EngineeringSoutheast UniversityNanjing210096China Department of Computer Engineering National Institute of TechnologyKurukshetra136119India Department of Computer Science and Information Engineering Asia UniversityTaichung41449Taiwan IT Fundamentals and Education Technologies Applications University of Information Technology and Management in RzeszowRzeszow Voivodeship100031Poland

In sensor networks,it is a challenge to ensure the security of data exchange between packet switching nodes holding different private *** order to solve this problem,the present study proposes a scheme called multi-conditional proxy broadcast re-encryption(MC-PbRE).The scheme consists of the following roles:the source node,proxy server,and the target *** the condition is met,the proxy can convert the encrypted data of the source node into data that the target node can directly *** allows the proxy server to convert the ciphertext of the source node to a new ciphertext of the target node in a different group,while the proxy server does not need to store the key or reveal the *** the same time,the proxy server cannot obtain any valuable information in the *** paper formalizes the concept of MC-PbRE and its security model,and proposes a MC-PbRE scheme of ciphertext ***,the scheme security has been proved in the random oracle.

关键词： Proxy re-encryption sensor network security broadcast re-encryption

Characterization of Ion Contents and Metabolic Responses to Salt Stress of Different Arabidopsis AtHKT1;1 Genotypes and Their Parental Strains

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Molecular Plant 2013年第2期6卷 350-368页

作者： Camilla b. Hill Deepa jha Antony bacic Mark Tester Ute Roessner Australian Centre for Plant Functional Genomics School of Botany University of Melbourne Victoria 3010 Australia Australian Centre for Plant Functional Genomics University of Adelaide Waite Campus Glen Osmond 5064 SA Australia Metabolomics Australia School of Botany University of Melbourne Victoria 3010 Australia bio21 Molecular Science and biotechnology Institute University of Melbourne Victoria 3010 Australia ARC Centre of Excellence in Plant Cell Walls School of Botany University of Melbourne Victoria 3010 Australia

Plants employ several strategies to maintain cellular ion homeostasis under salinity stress, including mediat-ing ion fluxes by transmembrane transport proteins and adjusting osmotic pressure by accumulating osmolytes. The HKT （high-affinity potassium transporter） gene family comprises Na^＋ and Na^＋/K^＋ transporters in diverse plant species, with HKT1,1 as the only member in Arabidopsis thaliana. Cell-type-specific overexpression of AtHKT1;1 has been shown to prevent shoot Na^＋ overaccumulation under salinity stress. Here, we analyzed a broad range of metabolites and elements in shoots and roots of different AtHKT1;1 genotypes and their parental strains before and after salinity stress, revealing a reciprocal relationship of metabolite differences between an AtHKT1;1 knockout line （hktl;1） and the AtHKT1;1 overex- pressing lines （E2586 UASGAL4：HKT1;1 and J2731＊UASGAL4：HKT1;1）. Although levels of root sugars were increased after salt stress in both AtHKTI,1 overexpressing lines, E2586 UASGAL4：HKT1;1 showed higher accumulation of the osmopro-tectants trehalose, gentiobiose, and melibiose, whereas J2731＊UASGAL4：HKT1;1 showed higher levels of sucrose and raffinose, compared with their parental lines, respectively. In contrast, the knockout line hktl,1 showed strong increases in the levels of the tricarboxylic acid （TCA） cycle intermediates in the shoots after salt treatment. This coincided with a significant depletion of sugars, suggesting that there is an increased rate of carbon influx into the TCA cycle at a constant rate of C-efflux from the cycle, which might be needed to support plant survival during salt stress. Using correlation analysis, we identified associations between the Na^＋ content and several sugars, suggesting that regulation of sugar metabolism is important in plant responses to salinity stress.

关键词： abiotic stress salinity salt tolerance HKT sodium transporter, metabolomics enhancer trap system.

Soaking Induced Changes in Chemical Composition, Glycemic Index and Starch Characteristics of basmati Rice

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Rice science 2015年第5期22卷 227-236页

作者： S.J.KALE S.K.jha G.K.jha J.P.SINHA S.b.LAL Division of Food Science and Post Harvest Technology Indian Agricultural Research Institute Division of Agricultural Economics Indian Agricultural Research Institute Division of Agricultural Engineering Indian Agricultural Research Institute Division of Computer Applications Indian Agricultural Research Institute

An attempt was made to determine the qualitative changes in basmati rice （Pusa basmati 1121, Pbl121） during soaking at 40 ℃ to 80 ℃. Soaking temperature had significant effect （a = 0.01） on chemical composition, glycemic index and starch characteristics of rice. Starch content, apparent amylose content, crude protein content and crude fat content in un-soaked rice were found to be 73.24%, 27.26%, 8.79% and 2.56%, respectively, but differences in these traits were observed after soaking. Amylose to amylopectin ratio （Am/Ap） decreased from 0.59 to 0.52 （soaked at 80 ℃）. Crude fibre and crude ash contents increased after soaking. The mineral composition （K, P, S, Ca, Mg, Mn, Fe, Cu and Zn） in soaked rice was found to be 16.46% higher than un-soaked rice at the same degree of polishing. Glycemic index of un-soaked rice was found to be 58.41, but decreased to 54.31 after soaking at 80 ℃. Pasting properties, scanning electron microscope images, and X-ray diffractograms suggested partial gelatinization of starch in the temperature range of 60 ℃ to 80 ℃. based on qualitative changes in rice （apparent amylose content, Am/Ap ratio and crystallinity rate）, it was concluded that intermediate soakincl temperatures （60 ℃ to 70 ℃） would be useful for soaking of Pb1121.

关键词： basmati rice soaking glycemic index starch characteristic temperature chemicalcomposition crystallinity

Refractive Index and Electronic Polarizability of Ternary Chalcopyrite Semiconductors

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Chinese Physics Letters 2015年第12期32卷 147-151页

作者： KUMAR V. SINHA Anita SINGH b.P. SINHA A.P. jha V. Department of Electronics Engineering Indian School of Mines

Simple models are proposed for the calculation of refractive index n and electronic polarizability α of AⅠbⅢC2Ⅵ and AⅡbⅣC2Ⅴ compounds of groups of chalcopyrite semiconductors from their energy gap data. The values family and 12 compounds of AⅡbⅣC2Ⅴ family are calculated for the work. The proposed models are applicable for the whole range of energy gap materials. The calculated values are compared with the available experimental and reported values. A fairly good agreement between them is obtained.

关键词： Te In Refractive Index and Electronic Polarizability of Ternary Chalcopyrite Semiconductors