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Chinese Physics Letters 2012年第5期29卷 154-156页

作者： M.A.ismail S.J.Tan N.S.Shahabuddin S.W.harun h.Arof h.Ahmad Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia Photonics Research Center Department of PhysicsUniversity of Malaya50603 Kuala LumpurMalaysia

A mode-locked erbium-doped fiber laser (EDFL) is demonstrated using a highly concentrated erbium-doped fiber (EDF) as the gain medium in a ring configuration with and without a saturable absorber (SA).Without the SA,the proposed laser generates soliton pulses with a repetition rate of 12 Mhz,pulse width of 1.11 ps and energy pulse of *** incorporating SA in the ring cavity,the optical output of the laser changes from soliton to stretched pulses due to the slight change in the group velocity *** the SA,a cleaner pulse is obtained with a repetition rate of 11.3 Mhz,a pulse width of 0.58ps and a pulse energy of 2.3pJ.

关键词： pulse fiber Erbium

Analytic approximate solutions of diffusion equations arising in oil pollution

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Journal of Ocean Engineering and Science 2021年第1期6卷 62-69页

作者： hijaz Ahmad Tufail A.Khan hülya Durur G.M.ismail Asıf Yokus Department of Basic Sciences University of Engineering and TechnologyPeshawar25000Pakistan Department of Computer Engineering Faculty of EngineeringArdahan UniversityArdahan75000Turkey Department of Mathematics Faculty of ScienceSohag UniversitySohag82524Egypt Department of Actuary Faculty of ScienceFirat UniversityElazig23200Turkey Department of Mathematics Faculty of ScienceIslamic University of Madinah170MadinahSaudi Arabia

In this article,modified versions of variational iteration algorithms are presented for the numerical simulation of the diffusion of oil *** numerical examples are given to demonstrate the applicability and validity of the proposed *** obtained results are compared with the existing solutions,which reveal that the proposed methods are very effective and can be used for other nonlinear initial value problems arising in science and engineering.

关键词： Modified variational iteration algorithm-II Diffusion equation Allen-Cahn equation Parabolic equation MVIA-I

Experimental determination of Cd^2＋ adsorption mechanism on low-cost biological waste

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Frontiers of Environmental Science & Engineering 2013年第3期7卷 356-364页

作者： Farhah Amalya ismail Ahmad Zaharin ARIS Environmental Forensics Research Centre Faculty of Environmental Studies Universiti Putra Malaysia UPM Serdang 43400 Malaysia

Carbonate shells have an astonishing ability in the removal of Cd^2＋ in a short time period with emphasis on being a low cost adsorbent. In the present study, the sorption capacity of carbonate shells was studied for Cd^2＋ in batch experiments. The influence of different carbonate shell sizes and physico-chemical factors were evaluated and the results were analyzed for its correlation matrices by using Predictive Analytics Software （PASW）. The miner- alogy state of aqueous solution regarding the saturation index was simulated using PhREEQC to identify the Cd^2＋ uptake mechanism. The Cd uptake rates were calculated as well as Ca^2＋, hCO3- concentration, ph, ambient humidity and temperature were measured. Cd2＋ removal of 91.52% was achieved after 5 h adsorption. The adsorption efficiencies were significantly influenced by ph as they increased with the increase of ph from acidic solution （5.50±0.02） to slightly alkaline （7.60±0.05）. In addition, the mineralogy state of aqueous solution calculated from PhREEQC confirmed that the increment of Ca^2＋ and hCO3- concentrations in solution was attributed to the dissolution of carbonate shells. Moreover, the ion exchange adsorption mechanism of Cd^2＋ toward Ca^2＋ was identified as the process involved in Cd^2＋ uptake.

关键词： carbonate shell cadmium heavy metal,adsorption mechanism saturation state

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

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

Direct C-h Bond Activation of Benzoxazole and Benzothiazole with Aryl Bromides Catalyzed by Palladium（Ⅱ）-N-heterocyclic Carbene Complexes

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Chinese Journal of Chemistry 2018年第9期36卷 837-844页

作者： Murat Kaloglu Nazan Kaloglur ismail Ozdemir Department of Chemistry Faculty of Science and Arts inonu University 44280 Malatya Turkey Catalysis Research and Application Center inonu University 44280Malatya Turkey

herein, we report that a series of novel palladium（II）-NhC complexes （NhC=N-heterocyclic carbene） were synthesized. The structures of all novel complexes were characterized by ^1h NMR, ^13C NMR, FT-IR spectroscopy and elemental analysis techniques. These palladium（ll）-NhC complexes were tested as efficient catalysts in the direct C-h bond activation of benzoxazole and benzothiazole with aryl bromides in the presence of 1 mol% catalyst loading at 150 ℃ for 4 h. Under the given conditions, various aryl bromides were successfully applied as the arylating reagents to achieve the 2-arylbenzoxazoles and 2-arylbenzothiazoles in acceptable to high yields.

关键词： benzimidazolium bromide benzoazoles direct C-h bond activation N-heterocyclic carbene palladium

Indole and Its Derivatives as Corrosion Inhibitors for C-Steel during Pickling

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Journal of Materials Science & Technology 2000年第3期16卷 291-296页

作者： S.h.Sanad, A.A.ismail and A.A.El-Meligi (Physical Chemistry Dept., National Research Centre, Dokki, Cairo, Egypt) Physical Chemistry Dept. National Research Centre Dokki Cairo Egypt

The corrosion of three types of C-steel in 10% hydrochloric acid solution has been investigated in the absence and the presence of the inhibitors, indole (A), indole acetic acid (B), indole butyric acid (C), and 3-acetyl indole (D), by weight-loss measurements at different temperatures (30～70℃). The results showed that inhibiting efficiency depended upon the presence of the substituted groups in the pyrrole ring. The inhibiting efficiency of the inhibitors increased in the order: Inh. Ch. Bh. Ah. D. Linear Arrhenius plots were obtained in the absence and the presence of inhibitors. Results elucidated the effect of temperatures and molecular structure on the inhibition efficiency. The activation energy, Ea, of the three alloys was calculated and it was found that it depended on the type of steel and inhibitor.

关键词： Carbon steel

Total hip replacement:A meta-analysis to evaluate survival of cemented,cementless and hybrid implants

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World Journal of Orthopedics 2017年第2期8卷 192-207页

作者： Phedy Phedy h Dilogo ismail Charles hoo Yoshi P Djaja Departement of Orthopaedic and Traumatology Fatmawati General HospitalFaculty of Medicine Universities Indonesia Departement of Orthopaedic and Traumatology Ciptomangunkusumo General HospitalFaculty of Medicine Universities Indonesia

AIM To determine whether cemented, cementless, or hybrid implant was superior to the other in terms of survival *** Systematic searches across MEDLINE, CINAhL, and Cochrane that compared cemented, cementless and hybrid total hip replacement(ThR) were performed. Two independent reviewers evaluated the risk ratios of revision due to any cause, aseptic loosening, infection, and dislocation rate of each implants with a pre-determined form. The risk ratios were pooled separately for clinical trials, cohorts and registers before pooled altogether using fixed-effect model. Meta-regressions were performed to identify the source of heterogeneity. Funnel plots were analyzed. RESULTS Twenty-seven studies comprising 5 clinical trials, 9 cohorts, and 13 registers fulfilled the research criteria and analyzed. Compared to cementless ThR, cemented ThR have pooled RR of 0.47(95%CI: 0.45-0.48), 0.9(0.84-0.95), 1.29(1.06-1.57) and 0.69(0.6-0.79) for revision due to any reason, revision due to aseptic loosening, revision due to infection, and dislocation respectively. Compared to hybrid ThR, the pooled RRs of cemented ThR were 0.82(0.76-0.89), 2.65(1.14-6.17), 0.98(0.7-1.38), and 0.67(0.57-0.79) respectively. Compared to hybrid ThR, cementless ThR had RRs of 0.7(0.65-0.75), 0.85(0.49-1.5), 1.47(0.93-2.34) and 1.13(0.98-1.3).CONCLUSION Despite the limitations in this study, there was some tendency that cemented fixation was still superior than other types of fixation in terms of implant survival.

关键词： Total hip replacement Implant survival Cemented Cementless hybrid Meta-analysis

Cadmium Selenide Polymer Microfiber Saturable Absorber for Q-Switched Fiber Laser Applications

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Chinese Physics Letters 2017年第9期34卷 54-57页

作者： A.h.A.Rosol h.A.Rahman E.I.ismail N.Irawati Z.Jusoh A.A.Latiff S.W.harun Faculty of Electrical Engineering University Teknologi Mara Shah Alam 40450 Malaysia Department of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia Faculty of Electrical Engineering University Teknologi Mara (Terengganu) Dungun 23000 Malaysia Photonics Research Centre University of Malaya Kuala Lumpur 50603 Malaysia

We demonstrate the generation of a Q-switching pulse train in an erbium-doped fiber laser （EDFL） cavity using a newly developed cadmium selenide （CdSe） based saturable absorber （SA）. The SA is obtained by embedding CdSe nanomaterials into a polymethyl methacrylate （PMMA） microfiber. It is incorporated into an EDFL cavity to generate a Q-switched laser operating at 1533.6nm. The repetition rates of the produced pulse train are tunable within 37–64khz as the pump power is varied from 34mW to 74mW. The corresponding pulse width reduces from 7.96μs to 4.84μs, and the maximum pulse energy of 1.16nJ is obtained at the pump power of 74mW.

关键词： Cadmium Selenide Polymer Microfiber Saturable Absorber for Q-Switched Fiber Laser Applications SA

Radiological characterization of building materials used in Malaysia and assessment of external and internal doses

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Nuclear Science and Techniques 2019年第3期30卷 82-96页

作者： Shittu Abdullahi Aznan Fazli ismail Supian Samat Nuclear Science Program Faculty of Science and Technology Universiti Kebangsaan Malaysia (UKM) Department of Physics Faculty of Science Gombe State University Centre for Frontier Science Faculty of Science and Technology Universiti Kebangsaan Malaysia (UKM)

In this study, the activity concentrations of ^(226)Ra,^(232)Th,^(222)Rn, and ^(40)K, emanation fractions(P),equilibrium equivalent concentration(EEC), and mass exhalation rates(E_m) of radon released from building materials used in Malaysia were studied using gamma-ray spectrometer with hPGe detector. Radiological parameters[activity concentration index(ACI), indoor air-absorbed dose rate(D_(in)), annual effective dose(AED_(in)) from external and internal(E_(Rn)), soft tissues(h_(ST)) and lung(h_L), and effective dose equivalent(h_(eff))] were estimated to evaluate radiological hazards due to the use of these building materials: sand, cement, gravel, bricks, tiles, fly ash, white cement, and ceramic raw materials. The measured P, EEC,and E_m vary from 10 to 30%, 0.9 to 22 Bq m^(-3), and 33 to 674 mBq h^(-1) kg^(-1), respectively, while the calculated ACI and AED_(in) vary from 0.1 ± 0.01 to 2.1 ± 0.1 and 0.1 ± 0.01 to 2.4 ± 0.6 mSv y^(-1), respectively. On the other hand, the internal annual effective dose ranges from 0.1 to 1.4 mSv y^(-1). The estimated radiological risk parameters were below the recommended maximum values, and radiological hazards associated with building materials under investigation are therefore negligible.

关键词： Indoor radon Emanation fraction Equilibrium equivalent concentration Mass exhalation rate Annual effective dose Effective dose equivalent