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Open Journal of Applied Sciences 2017年第9期7卷 458-484页

作者： Abdul Rauf shah Hajira tahir Hafiz muhammad Kifayat Ullah Asma Adnan Department of Chemistry University of Karachi Karachi Pakistan

The study was useful for the treatment of Reactive red 223 (R223) and Coomassie brilliant blue R250 (CBBR250) binary dye system by electrocoagulation process (EC). moreover, the Al and Fe electrode were used as an anode and cathode, respectively. The response surface methodology (RSm) was adopted by utilizing central composite design to plan the experimental runs. The EC process was preceded under the effect of operating parameters including pH, NaCl, voltage and electrolysis time. The % color and COD removals were examined as response variables. The removal efficiency of RR223 and CBBR250 dye at optimum values was 89% and 94% and COD removal was 100%. The kinetic study was performed to determine the rate and rate constant. First and second order kinetic models were studied to figure out the exact mechanism of the dye removal using EC process. The estimated cost of the experimental design about 4.486 US$/dm3 was also determined. This study showed that EC process is an economical way for the treatment of waste water.

关键词： Electrocaogulation Central Composite Design Kinetic Study FTIR Color COD

Computational aerodynamic analysis on perimeter reinforced(PR)-compliant wing

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Chinese Journal of Aeronautics 2013年第5期26卷 1093-1105页

作者： N.I.Ismail A.H.Zulkifli m.Z.Abdullah m.Hisyam Basri Norazharuddin shah Abdullah Faculty of mechanical Engineering Universiti Teknologi MARA40450 Shah AlamSelangorMalaysia School of mechanical Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia School of materials and mineral Resources Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia

Abstract Implementing the morphing technique on a micro air vehicle （mAV） wing is a very chal- lenging task, due to the mAWs wing size limitation and the complex morphing mechanism. As a result, understanding aerodynamic characteristics and flow configurations, subject to wing structure deformation of a morphing wing mAV has remained obstructed. Thus, this paper presents the investigation of structural deformation, aerodynamics performance and flow formation on a pro- posed twist morphing mAV wing design named perimeter reinforced （PR）-compliant wing. The numerical simulation of two-way fluid structure interaction （FSI） investigation consist of a quasi- static aeroelastic structural analysis coupled with 3D incompressible Reynolds-averaged Navier- Stokes and shear-stress-transport （RANS-SST） solver utilized throughout this study. Verification of numerical method on a rigid rectangular wing achieves a good correlation with available exper- imental results. A comparative aeroelastic study between PR-compliant to PR and rigid wing per- formance is organized to elucidate the morphing wing performances. Structural deformation results show that PR-compliant wing is able to alter the wing＇s geometric twist characteristic, which has directly influenced both the overall aerodynamic performance and flow structure behavior. Despite the superior lift performance result, PR-compliant wing also suffers from massive drag penalty, which has consequently affected the wing efficiency in general. Based on vortices investigation, the results reveal the connection between these aerodynamic performances with vortices formation on PR-comoliant wing.

关键词： Aerodynamics Aeroelasticity Fluid structure interaction micro air vehicle (mAV) morphing wing

Evaluation of Various modification methods for Enhancing the Performance of Recycled Concrete Aggregate

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Journal of Renewable materials 2022年第10期10卷 2685-2698页

作者： Xiaoyan Liu Li Liu Junqing Zuo Pingzhong Zhao Xian Xie Shijie Li Kai Lyu Chunying Wu Surendra P.shah College of mechanics and materials Hohai UniversityNanjing210098China Shanghai Construction Group Co. Ltd.Shanghai200080China College of Civil and Transportation Engineering Hohai UniversityNanjing210098China Jiangsu Transportation Institute Co. Ltd.Nanjing210017China Center for Advanced Cement-Based materials(ACBm) Northwestern UniversityEvanstonII 60208USA

Due to the existence of the attached mortar,the performance of the recycled concrete aggregate(RCA)is inferior to the natural aggregate,which significantly limits its wide application in *** this study,five kinds of modified solutions were used to modify the surface of RCA,and the modification effects were *** results showed that sodium silicate,nano-silica(NS),Bacillus pasteurii and soybean powder had relatively good modification effects on RCA,which could reduce the crushing value and water absorption,and increase apparent *** composite solution(15%sodium silicate and 2%NS)and soybean powder solution had better modification *** 28 d compressive strength and splitting tensile strength of recycled aggregate concrete(RAC)prepared by RCA modified by soybean powder solution were 4.6%and 5.2%higher than those prepared by RCA modified by composite solution,*** indicates that among the five kinds of modified solutions,soybean powder solution has the best modification effect on RCA,and the optimal soaking time of soybean powder solution is 8 *** this time,the crushing value,water absorption and apparent density of RCA are 12.8%,5.3%,and 2653 kg/m^(3),*** research results of this study provide a reference for the modification of RCA and its efficient utilization.

关键词： Recycled concrete aggregate modification solution soybean powder physical properties

Optimization of aerodynamic efficiency for twist morphing mAV wing

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Chinese Journal of Aeronautics 2014年第3期27卷 475-487页

作者： N.I.Ismail A.H.Zulkifli m.Z.Abdullah m.Hisyam Basri Norazharuddin shah Abdullah Faculty of mechanical Engineering Universiti Teknologi MARA Shah Alam 40450 Malaysia School of mechanical Engineering Universiti Sains Malaysia Engineering Campus Nibong Tebal 14300 Malaysia School of materials and mineral Resources Engineering Universiti Sains Malaysia Engineering Campus Nibong Tebal 14300Malaysia

Twist morphing （Tm） is a practical control technique in micro air vehicle （mAV） flight. However, Tm wing has a lower aerodynamic efficiency （CL/CD） compared to membrane and rigid wing. This is due to massive drag penalty created on Tm wing, which had overwhelmed the succes- sive increase in its lift generation. Therefore, further CL/CDmax optimization on Tm wing is needed to obtain the optimal condition for the morphing wing configuration. In this paper, two-way fluid- structure interaction （FSI） simulation and wind tunnel testing method are used to solve and study the basic wing aerodynamic performance over （non-optimal） Tm, membrane and rigid wings. Then, a multifidelity data metamodel based design optimization （mBDO） process is adopted based on the Ansys-DesignXplorer frameworks. In the adaptive mBDO process, Kriging metamodel is used to construct the final multifidelity CL/CD responses by utilizing 23 multi-fidelity sample points from the FSI simulation and experimental data. The optimization results show that the optimal Tm wing configuration is able to produce better CL/CDmax magnitude by at least 2% than the non-optimal Tm wings. The flow structure formation reveals that low TV strength on the optimal Tm wing induces low CD generation which in turn improves its overall CL/CDmax performance.

关键词： Aerodynamics Fluid structure interaction micro air vehicle Optimization Twist morphing

Investigation of magnetoelectric effect in lead free K0.5Na0.5NbO3–BaFe12O19 novel composite system

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Journal of Advanced Ceramics 2019年第3期8卷 333-344页

作者： Yogesh KUmAR KLYADAV Jyoti shah RKKOTNALA Smart materials Research Laboratory Department of PhysicsIndian Institute of Technology RoorkeeRoorkee247667India National Physical Laboratory New DelhiDelhi110012India

Lead-free magnetoelectric composites(1-x)K0.5Na0.5NbO3–(x)BaFe12O19(x = 30, 40, and 50 wt%) are synthesized using solid state reaction method. X-ray diffraction(XRD) patterns confirm formation of diphase composites. Field emission scanning electron microscopy(FE-SEm) gives information about grain size, connectivity, and microstructure of constituent phases. Dielectric parameters of composite samples are studied as a function of temperature and the transition temperatures corresponding to both the constituent phases are observed in the composite samples. Dielectric constant has been found to decrease with addition of ferrite. Room temperature multiferroic behaviour has been confirmed using P–E and m–H hysteresis loops and magnetoelectric measurement. Polarization is found to decrease;however, magnetization increases with ferrite weight percentage. The highest αmE of 4.08 mV/(cm·Oe) is obtained for x = 30 wt% composite and it is realized that ferrite content significantly affects magnetoelectric behaviour.

关键词： composite materials X-ray diffraction(XRD) microstructure dielectric multiferroic

Effect on Landau damping rates for a non-maxwellian distribution function consisting of two electron populations

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Chinese Physics B 2013年第3期22卷 358-365页

作者： m.N.S.Qureshi S.Sehar H.A.shah J.B.Cao Space Science Institute Beihang University Department of Physics Government College University

In many physical situations where a laser or electron beam passes through a dense plasma,hot low-density electron populations can be generated,resulting in a particle distribution function consisting of a dense cold population and a small hot *** of such low-density electron distributions can alter the wave damping rate.A kinetic model is employed to study the Landau damping of Langmuir waves when a small hot electron population is present in the dense cold electron population with non-maxwellian distribution *** of plasma from maxwellian distributions significantly alters the damping rates as compared to the maxwellian *** damping is found for highly nonmaxwellian distributions as well as plasmas with a higher density and hot electron *** of weak damping is also established when the distribution contains broadened flat tops at the low energies or tends to be *** results may be applied in both experimental and space physics regimes.

关键词： Landau damping Langmuir waves two electron populations non-maxwellian distribution function

Reflection of thermoelastic wave on the interface of isotropic half-space and tetragonal syngony anisotropic medium of classes 4, 4/m with thermomechanical effect

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Chinese Physics B 2016年第3期25卷 414-417页

作者： Nurlybek A Ispulov Abdul Qadir m A shah Ainur K Seythanova Tanat G Kissikov Erkin Arinov S. Toraygyrov Pavlodar State University Pavlodar 140008 Kazakhstan Department of Electrical Engineering Sukkur Institute of Business Administration Sindh Pakistan Zhezkazgan University Kazakhstan

The thermoelastic wave propagation in a tetragonal syngony anisotropic medium of classes 4, 4/m having heterogeneity along z axis has been investigated by employing matrizant method. This medium has an axis of second-order symmetry parallel to z axis. In the case of the fourth-order matrix coefficients, the problems of wave refraction and reflection on the interface of homogeneous anisotropic thermoelastic mediums are solved analytically.

关键词： anisotropic medium thermoelasticity harmonic waves dispersion

SOmE INTEGRAL mEAN ESTImATES FOR POLYNOmIALS

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Analysis in Theory and Applications 2007年第2期23卷 101-111页

作者： A. Aziz W. m. shah University of Kashmir India Bemina College India

In this paper we establish L^q inequalities for polynomials, which in particular yields interesting generalizations of some Zygmund-type inequalities.

关键词： polynomial Bernstein's inequality L^q mean estimate zero

In vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah

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Asian Pacific Journal of Tropical medicine 2011年第9期4卷 717-721页

作者： m Amzad Hossain muhammad Dawood shah Charles Gnanaraj muhammad Iqbal Biotechnology Research Institute Universili Malaysia Sabah.Licked Bag No.207388999 Kota KinabaluSabahMalaysia

Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from ***:The dry powder leaves of Tetrastigma were extracted with different organic solvent such as *** acetate,chloroform,butanol and aqueous *** total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane,ethyl acetate,chloroform,butanol and aqueous ethanol were determined by Folin-Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity usingα,α-diphenyl-β-picrylhydrazyl (DPPH) ***:The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract(386.22 mg/g) followed by ethyl acetate(190.89 mg/g).chloroform(175.89 mg/g).hexane(173.44 mg/g).and Imtanol extract (131.72 mg/g) and the phenolic contents not detected in essential *** antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract>ethyl acetate extract>chloroform>butanol>hexane extract also the antioxidant activity was not detected in essential ***:The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that *** of Tetrastigma being rich in phenolics may provide a good source of antioxidant.

关键词： Total phenolics Flavonoids Antioxidant aotivity Essential oil Extracts Tetrastigma

Dielectric and conducting behavior of gadolinium–terbium fumarate heptahydrate crystals

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Journal of Advanced Dielectrics 2015年第3期5卷 19-26页

作者： m.D.shah B.Want Solid State Research Laboratory Department of Physics University of KashmirSrinagar 190006India

Gadolinium-terbium fumarate heptahydrate crystals were grown in silica gel by using single gel diffusion *** crystals were characterized by different physico-chemical techniques of *** X-ray diffraction results showed that the grown material is purely crystalline in *** analyses suggested the chemical formula of the compound to be Gd Tb(C_(4)H_(2)O_(4)_(3)·7H_(2)*** dispersive X-ray analysis confirmed the presence of Gd and Tb in the title *** dielectric and conductivity studies of the grown compound were carried as function offrequency of applied field and the *** grown material showed a dielectric anomaly which was correlated with its thermal *** ac conductivity of the material showed Jonscher's power law behavior:σ(ω)=σ_(0)+Aω^(s),with a temperature-dependent power exponent s(mperature and frequency.

关键词： Single crystal growth characterization mixed rare earth compound ionic conductivity