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journal of rare Earths 2015年第8期33卷 837-845页

作者： radha Velchuri Suresh Palla G.ravi Naveen Kumar Veldurthi j.r.reddy M.Vithal Department of Chemistry Osmania University

rare earth ortho-oxomolybdates of composition Ln2/aMoO4 （Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er and Y） were prepared by metathesis reaction. All these materials were characterized by powder X-ray diffraction, Fourier transform-infrared spectroscopy （FT-Ir） and UV-Vis diffuse reflectance spectra. The rietveld analysis of all the samples was carried out to obtain the unit cell parameters and reliability factors. All the materials were crystallized in tetragonal lattice with I41/a space group. The infrared spectra of all the samples were characterized by bands due to MoO42 units. The bandgap energies of all the samples were obtained from UV-Vis DrS spectra. The luminescence spectra of Ln2/3MoO4 （Ln=Pr, Eu and Dy） showed characteristic transitions of the rare earth ions. The visible light photocatalytic activity of all the samples was studied against degradation of methylene blue.

关键词： metathesis X-ray diffxaction Ir spectroscopy UV-Vis spectroscopy photodegradation rare earths

A comparative analysis of unsteady and steady Buongiorno’s Williamson nanoliquid flow over a wedge with slip effects

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Chinese journal of Chemical Engineering 2020年第7期28卷 1767-1777页

作者： r.Chandra Sekhar reddy P.Sudarsana reddy Department of Mathematics Rajeev Gandhi Memorial Collge of Engineering&TechnologyNandyalA.P.India

Comparison between unsteady and steady MHD Buongiorno’s model Williamson nanoliquid flow through a wedge with slip effects,chemical reaction and radiation is made in this *** and Brownian motion are also considered in this *** similarity variables are presented to transmute the governing PDEs into the set of non-linear *** most widely authenticated finite element method is implemented to analyze these set of ODEs *** behavior of concentration,temperature and velocity sketches for varied values of relevant parameters is numerically calculated and the outcomes are plotted through *** numerical values of dimensionless rates of mass transfer,heat and velocity are also evaluated and depicted through *** is noted that with upsurging values of angle of wedge parameter,the distributions of temperature of the liquid intensify in both steady and unsteady cases.

关键词： Finite element method Chemical reaction Williamson nanoliquid Thermophoresis Thermal radiation Brownian motion

Thermal radiation effect on unsteady threedimensional MHD flow of micropolar fluid over a horizontal surface of a parabola of revolution

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Propulsion and Power research 2022年第1期11卷 129-142页

作者： S.r.r.reddy P.Bala Anki reddy Center for Nonlinear Systems Chennai Institute of TechnologyChennai600069T.N.India Department of Mathematics S.A.S.Vellore Institute of TechnologyVellore632014T.N.India

This paper explores the time-dependent magnetohydrodynamics(MHD)micropolar fluid flow over a three-dimensional variable stretching surface in the occurrence of radiation *** model time-dependent partial differential equations(PDE’s)in three independent variables are transformed into ordinary differential equations(ODE’s)by the suitable selfsimilarity *** perturbation method(HPM)and runge-Kutta(rK)4^(th) order method along with shooting technique are used in the present *** also,HPM results are compared with runge-Kutta(rK)4^(th) order method along with the shooting *** velocity,micro rotation in x and y directions,temperature,skin friction factor and heat transfer rates are examined for the emerging *** velocity profiles and momentum boundary layer thickness intensification with increasing values of the vortex viscosity *** higher value of a magnetic parameter declines the skin friction *** type of investigation may be profitable to the polymer fluids,exotic lubricants,electronic chips,artificial fibers,drawing of copper wires,etc.

关键词： radiation parameter Magnetohydrodynamics Micropolar fluid Variable thickness sheet Homotopy perturbation method(HPM)

Microwave synthesis and spectroscopic characterization of manganese oxalate nanocrystals

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Particuology 2013年第3期11卷 340-345页

作者： S.Lakshmi reddy G.Udayabashkar reddy r.ramasubba reddy G.Siva reddy ray L.Frostc Tamio Endo Department of Physics Sri Venkateswara Degree College Department of Chemistry Sri Venkateswara University School of Chemistry Physics and Mechanical EngineeringScience and Engineering FacultyQueensland University of Technology Faculty of Engineering Mie University

The microwave synthesis of MnC204.2H2O nanoparticles was performed through the thermal double decomposition of oxalic acid dihydrate （C2H204.2H20） and Mn（OAc）2.4H2O solutions using a CATA-2r microwave reactor. Structural characterization was performed using X-ray diffraction （XrD）, particle size and shape were analyzed using transmission electron microscopy （TEM）. The chemical in the structures was investigated using electron paramagnetic resonance （EPr） as well as optical absorption spectra and near-infrared （NIr） spectroscopies. The nanocrystals produced with this method were pure and had a distorted rhombic octahedral *** oxalate

关键词： Lindbergite Electron paramagnetic resonance Optical absorption and NIr spectra Mn(ll) Water fundamentals

Mathematical modelling of couple stresses on fluid flow in constricted tapered artery in presence of slip velocity-effects of catheter

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Applied Mathematics and Mechanics(English Edition) 2014年第8期35卷 947-958页

作者： j.V.r.reddy D.SrIKANTH S.K.MUrTHY Department of Applied Mathematics Defence Institute of Advanced Technology Deemed UniversityPune 411025MaharastraIndia

This paper explores the mathematical model for couple stress fluid flow through an annular region. The above model is used for studying the blood flow be-tween the clogged （stenotic） artery and the catheter. The asymmetric nature of the stenosis is considered. The closed form expressions for the physiological parameters such as impedance and shear stress at the wall are obtained. The effects of various geomet-ric parameters and the parameters arising out of the fluid considered are discussed by considering the slip velocity and tapering angle. The study of the above model is very significant as it has direct applications in the treatment of cardiovascular diseases.

关键词： blood flow couple stress fluid stenosed artery tapered artery catheter

Major geologic events of the Cauvery Basin,India and their correlation with global signaturese——A review

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journal of Palaeogeography 2017年第1期6卷 69-83页

作者： r.Nagendra A.Nallapa reddy Department of Geology Anna UniversityChennai600025India

The present review is aimed at correlating major geologic events of the Cauvery Basin with analogous global episodes. The Cauvery Basin came into existence due to Gondwana break up during Late jurassic-Early Cretaceous by taphrogenic rift process. The first marine transgression close to Aptian/Albian boundary at the western margin of the basin terminates the syn-rift tectonic phase, which is also precise in adjoining Krishna-Godavari （KG） Basin. Two regional tectonic episodes are well documented in the basin which have global significance viz. （1） A major basinal uplift during late Turonian caused by Marion hot mantle plume resulted in widespread subaqueous volcanism in the southern part of the Cauvery Basin. This uplift also ted to relative sea level （rSL） fall of about 100 m in Cauvery and KG Basins and an unconformity of a magnitude of 2.3 Ma. The rSL fatt closely correlates with global sea level faU. This volcanic episode also resulted in Madagascar detachment from India. （2） The reunion hot mantle plume that ted to Deccan volcanism in central India resulted in E-SE tilt of the Cauvery Basin during upper Maastrichtian （CFI-CF3 zones）. This tilt caused a sea level fall of about 80 m and lateral withdrawal of sea by about 50 km developing a major erosional unconformity ranging in magnitude of -1.8-30 My. The magnitude of rSL correlates wetl with global sea level fall. This sea level fall caused widespread development of canyon features in the Cauvery Basin resulting in differential subaqueous erosion. The globally significant ocean anoxic events viz. OAE-Ib, OAE-1d, OAE-2 and OAE-3 are fairly discernible in the Cauvery Basin. The new isotopic palaeotemperature data suggests that southern India and Madagascar were located apparently in middle latitudes within the tropical-subtropical climatic zone during Atbian and early Maastrichtian. The magnitude of hiatus across K-Pg boundary varying from 0 to 30 Ma is estimated based on ptanktic foraminifera for subsurface sec

关键词： Cauvery Basin Correlation Geologic events Global episodes

Numerical simulation of self-similar thermal convection from a spinning cone in anisotropic porous medium

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journal of Hydrodynamics 2016年第2期28卷 184-194页

作者： O. Anwar BEG M. j. UDDIN T. BEG r. reddy GOrLA Spray research Group Petroleum and Gas Engineering Division Room G77 Newton Building School of Computing Science and Engineering (CSE) University of Salford M54WT UK Department of Mathematics American International University-Bangladesh Dhaka Bangladesh Engineering Mechanics Associates Dickenson Road Manchester M 16 England UK Department Mechanical Engineering Cleveland State University Cleveland Ohio USA

Self-similar steady natural convection thermal boundary layer flow from a rotating vertical cone to anisotropic Darcian porous medium is investigated theoretically and numerically. The transformed non-dimensional two-point boundary value problem is reduced to a system of coupled, highly nonlinear ordinary differential equations, which are solved subject to robust surface and free stream boundary conditions with the MAPLE 17 numerical quadrature software. Validation with earlier non-rotating studies is included, and also further verification of rotating solutions is achieved with a variational finite element method （FEM）. The rotational （spin） parameter emerges as an inverse function of the Grashof number. The influence of this parameter, primary Darey number, secondary Darcy number and Prandtl number on tangential velocity and swirl velocity, temperature and heat transfer rate are studied in detail. It is found that the dimensionless tangential velocity increases whilst the dimensionless swirl velocity and temperature decrease with the swirl Darcy number, tangential Darcy number and the rotational parameters. The model finds applications in chemical engineering filtration processing, liquid coating and spinning cone distillation columns.

关键词： self-similarity spinning cone finite element method (FEM) anisotropic porous medium heat transfer MAPLE FEM

Brain targeted delivery of paclitaxel using endogenous ligand

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Asian journal of Pharmaceutical Sciences 2016年第3期11卷 427-438页

作者： Sanjeev r.Acharya Padmanabha r.V.reddy Department of Pharmacognosy Nirma University Department of Pharmacy Institute of Pharmacy Nirma University

The objective of the present investigation was to formulate nanoparticles constructed using PLGA polymer for the effective targeted delivery to brain via nasal route. The PLGA nanoparticles were optimized using novel design of experiment technique by 23 full factorial design. Drug: polymer ratio（X1）, surfactant concentration（X2） and stirring speed（X3） were identified as critical process parameters, and its impact on particle size（Y1） and % entrapment efficiency（Y2） was studied. The optimized nanoparticle formulation was conjugated with glutathione as an endogenous ligand by using carbodiimide chemistry using(1-Ethyl-3-（3-dimethylaminopropyl）carbodiimide)（EDAC） as linker molecule. From Ellman's assay,it was found that a total of 691.27 ± 151 units of glutathione were conjugated upon each PLGA nanoparticle. The in vitro release studies as well as ex vivo studies revealed biphasic pattern of drug release with initial burst release followed by slow exponential release of drug over a period of 24 h. The in vivo biodistribution studies were conducted on rat following nasal administration of the nanoparticle formulation（conjugated and unconjugated）and were compared with plain paclitaxel suspension. The results clearly demonstrated that the brain targeting efficiency was enhanced with the glutathione conjugated formulation（387.474%） as compared to the unconjugated nanoparticle formulation（224.327%）. Further,the in vitro in vivo correlation studies revealed good relationship（r2> 0.95） as obtained from the levy plot. Glutathione proves to be an efficient vector for the successful transport of poor bioavailable drug to the brain.

关键词： Glutathione Biodistribution PLGA nanoparticles In vitro in vivo correlation (IVIVC)

Solvent-free aerobic oxidation of ethylbenzene over supported Ni catalysts using molecular oxygen at atmospheric pressure

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journal of Natural Gas Chemistry 2008年第3期17卷 293-297页

作者： G.raju P.Shiva reddy j.Ashok B.Mahipal reddy A.Venugopal Catalysis & Physical Chemistry Division Indian Institute of Chemical Technology

We investigated the aerobic oxidation of ethylbenzene in the absence of solvent or any additive carried out over Ni on different types of supports namely SiO2, hydroxyapatite, SBA-15, and USY Zeolites. The oxidation of ethylbenzene activities was measured in a round bottom flask immersed in oil bath at known reaction temperature. The physicochemical characteristics of the catalysts were examined by BET surface area, XrD, FT-Ir and the oxidation activities were correlated with the acidities of the catalysts obtained by TPD of NH3. It was observed that both hydroxyapatite and USY （13% Na2O） supported Ni catalysts displayed higher ethylbenzene conversion and 80% selectivity towards acetophenone.

关键词： nickel SBA-15 zeolites hydroxyapatite ethylbenzene oxidation TPD of NH3

Substrate Temperature Dependent Properties of Cu Doped NiO Films Deposited by DC reactive Magnetron Sputtering

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journal of Materials Science & Technology 2013年第7期29卷 647-651页

作者： Yarraguntla Ashok Kumar reddy Akepati Sivasankar reddy Pamanji Sreedhara reddy Department of Physics Sri Venkateswara UniversityTirupathi 517502India Division of Advanced Materials Engineering Kongju National UniversityBudaedongCheonan CitySouth Korea

The NiO-Cu composite films were deposited on a glass substrate at various substrate temperatures by DC reactive magnetron sputtering technique. The effect of substrate temperature on the structural, optical, morphological and electrical properties of the films was mainly investigated. X-ray diffraction studies revealed that when the substrate temperature increased to above 200 ℃, the preferred orientation tended to move to another preferred site from （220） to （111） and had a band gap values increased with increasing substrate observed that the grain size and root mean square stable cubic structure. The optical transmittance and temperature. From the morphological studies, it was roughness were increased with increasing substrate temperature. The electrical resistivity of the film decreased to 0.017 Ωcm at high substrate temperature of 400 ℃.

关键词： Sputtering NiO-Cu composite films Substrate temperature Crystallite size Electrical resistivity