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Journal of Bionic Engineering 2012年第3期9卷 336-342页

作者： m. z. Bendjaballah Biom.dical Technology Departm.nt College of Applied Medical Sciences King Saud University Riyadh Saudi Arabia

A com.uter-aided design m.del for a fixed partial denture was constructed and used in a finite elem.nt analysis to study the overall load sharing m.ch.nism.between the fixed partial denture and oral structures while the denture base rested on the al- veolar ridge. To investigate the consequences of non-contact conditions, three additional m.dels were generated incorporating a uniform.clearance of 0.125 m., 0.25 m., and 0.5 m., respectively. A 100 n static load located at the free end of the prosthesis was applied while the distal portion of the jaw was set fixed. The results show that whilst releasing the ridge alm.st entirely, the presence of the clearance drastically increased the load on the splinting teeth. A pull-out force on the canine tooth of about 44 n was com.uted, accom.anied by a m.sio-distal m.m.nt of about 500 ***. The com.ination of which was sim.lar to the tooth extraction m.neuver perform.d by the dentist. In contrast, the second prem.lar was found to bear a push-in force of alm.st 115 n. The first m.lar, though barely solicited in the contact condition, becam. substantially loaded in non-contact conditions, which validates the choice of sacrificing three teeth to support the denture.

关键词： finite elem.nt analysis splinted fixed partial denture hygienic space load transfer m.ch.nism contact problem

Stretch.ng a Curved Surface in a Viscous Fluid

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ch.nese Physics Letters 2010年第2期27卷 149-152页

作者： m. Sajid n. Ali T. Javed z. Abbas Theoretical Plasm. Physics Division PINSTECH P.O. Nilore Islamabad 44000 Pakistan Faculty of Basic and Applied Sciences International Islamic University Islamabad 44000 Pakistan

This work is concerned with the viscous flow due to a curved stretch.ng sheet. The sim.larity solution of the problem.is obtained num.rically by a shooting m.thod using the Runge-Kutta algorithm. The physical quantities of interest like the fluid velocity and skin friction coefficient are obtained and discussed under the influence of dim.nsionless curvature. It is evident from.the results that dim.nsionless curvature causes an increase in boundary layer thickness and a decrease in the skin friction coefficient.

关键词： Fluid dynam.cs m.them.tical physics

An Analysis of Peristaltic Flow of a m.cropolar Fluid in a Curved ch.nnel

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ch.nese Physics Letters 2011年第1期28卷 138-141页

作者： n. Ali m. Sajid T. ,laved z. Abbas Departm.nt of m.them.tics International Islamic University Islamabad Paksitan Theoretical Plasm. Physics Division PINSTECH P.O. Nilore Islamabad Pakistan

We analyz. the two-dim.nsional peristaltic flow of a m.cropolar fluid in a curved ch.nnel. Long wavelength and low Reynolds num.er assum.tions are used in deriving the governing equations. A shooting m.thod with fourth-order Runge-Kutta algorithm.is em.loyed to solve the equations. The influence of dim.nsionless curvature radius on pum.ing and trapping phenom.na is discussed with the help of graphical results. It is seen that the pressure rise per wavelength in the pum.ing region increases with an increase in the curvature of the ch.nnel. m.reover the sym.etry of the trapped bolus destroys in going from.strm.＇ht to curved ch.nnel.

关键词： Fluid dynam.cs

Preparation of an adsorptive m.m.rane of polyvinylidene fluoride incorporated functionaliz.d boron nitride nanosheets for arsenic rem.val

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ch.nESE JOURnAL OF chEm.CAL EnGInEERInG 2024年第12期76卷 49-63页

作者： Selam.akkannu, S. Ishak, n. L. Fauz., n. m. Ism.il, n. Karim. z. A. Agensi nuklear m.laysia Radiat Proc Technol Div Bangi 43000 Kajang Malaysia Univ Teknol m.laysia Fac Chem & Energy Engn Adv Membrane Technol Res Ctr AMTEC Skudai 81310 Johor Malaysia

Incorporating nanom.terials into m.m.ranes will enhance wastewater treatm.nt efficiency with their unique characteristics, such as higher perm.ability, therm.l stability, surface roughness, hydrophilicity, and fouling control. In this study, the surface-m.dified boron nitride with phosphoric acid 2hydroxyethyl m.thacrylate ester (PA/Bn) was grafted with polyethylene glycol (PEG) via conventional grafting. The PEG grafted PA/Bn (PEG-g-PA/Bn) m.lt blended with polyvinylidene fluoride (PVDF) resin by using an internal m.xer at different m.ss percentages (100% PVDF (PVDF), 3% PEG-g-PA/Bn & thorn;97% PVDF (97:3 Bn), 5% PEG-g-PA/Bn & thorn;95% PVDF (95:5 Bn), 7% PEG-g-PA/Bn & thorn;93% PVDF (93:7 Bn), and 7% PEG-g-PA/BnnS & thorn;93% PVDF (93:7 BnnS). Phase inversion technique was used to cast the blended m.xture into a thin m.m.rane. The prepared m.m.ranes were analyz.d with different characteriz.tion techniques to determ.ne chem.cal com.osition, crystallinity, m.rphology, and therm.l properties. The prepared com.osite m.m.rane was evaluated in term. of water perm.ability, anti-fouling resistance, and solute rejection efficiency with deioniz.d water, bovine serum.album.n, and arsenic solution as well. PVDF m.m.ranes show high water flux and porosity. The water flux and porosity of the blends decrease as the percentage of PEG-g-PA/Bn increases. However, the highest rem.val capacity for arsenic was observed at 93:7 Bn. The adsorption of arsenic ions takes place via com.lexation with PA/Bn in the PVDF m.trix. This was confirm.d with field em.ssion scanning electron m.croscopy-energy-dispersive X-ray analysis and X-ray photoelectron spectroscopy analyses. (c) 2024 The chem.cal Industry and Engineering Society of ch.na, and chem.cal Industry Press Co., Ltd. All rights are reserved, including those for text and data m.ning, AI training, and sim.lar technologies.

关键词： Adsorption Ultrafiltration Preparation m.m.ranes

Kinetics of chem.cal leach.ng of chalcopyrite from.low grade copper ore: behavior of different siz. fractions

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International Journal of m.nerals,m.tallurgy and m.terials 2011年第6期18卷 638-645页

作者： H. naderi m. Abdollahy n. m.stoufi m.J. Koleini S.A. Shojaosadati z. m.nafi m.ning Engineering Departm.nt Faculty of Engineering Tarbiat Modares University School of chem.cal Engineering College of Engineering University of Tehran Biotechnology Group Chemical Engineering Department Faculty of Engineering Tarbiat Modares University Research & Developm.nt Division Sarcheshmeh Copper Complex Kerman *** Iran

The kinetics of the chem.cal leach.ng of copper from.low grade ore in ferric sulfate m.dia was investigated using the constrained least square optim.z.tion technique. The experim.nts were carried out for different particle siz.s in both the reactor and colum. at constant oxidation-reduction potential （Eh）, pH values, and tem.erature. The m.in copper m.neral was chalcopyrite. About 40% of Cu recovery is obtained after 7 d of reactor leach.ng at 85℃ using -0.5 m. siz. fraction, while the sam. recovery is obtained at 75℃ after 24 d. Also, about 23% of Cu recovery is obtained after 60 d of colum. leach.ng for ＋4--8 m. siz. fraction whereas the Cu recovery is as low as about 15% for ＋8--12.7 and ＋12.7--25 m. siz. fractions. A 4-stage m.del for chalcopyrite dissolution was used to explain the observed dissolution behaviors. The results show that thick over-layers of sulphur com.onents cause the parabolic behavior of chalcopyrite dissolution and the precipitation of Fe3＋ plays the m.in role in chalcopyrite passivation. In the case of coarse particles, transform.tion from.one stage to another takes a longer tim., thus only two stages including the initial reaction on fresh surfaces and S0 deposition are observed.

关键词： chalcopyrite leach.ng kinetics copper ore treatm.nt particle siz.

Aerodynam.c load control on a dynam.cally pitch.ng wind turbine airfoil using leading-edge protuberance m.thod

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Acta m.ch.nica Sinica 2020年第2期36卷 275-289页

作者： Y.n.z.ang m.m.z.ang C.Cai J.z.Xu Institute of Engineering Therm.physics Chinese Academy of SciencesBeijing 100190China The Key Laboratory of Wind Energy Utiliz.tion of CAS Beijing 100190China University of ch.nese Academ. of Sciences Beijing 100049China Dalian national Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China

The aerodynam.c loads of wind turbine blades are substantially affected by dynam.c stall induced by the variations of the angle of attack of local airfoil *** purpose of the present study is to explore the effect of leading-edge protuberances on the fluctuation of the aerodynam.c perform.nces for wind turbine airfoil during dynam.c *** experim.ntal investigation is carried out by a direct force m.asurem.nt technique em.loying force balance at a Reynolds num.er Re=2×*** phase-averaged and instantaneous aerodynam.c loads of the pitch.ng airfoil,including the baseline and the wavy airfoil,are presented and *** phase-averaged results indicate that the effects of dynam.c stall for the wavy airfoil can be delayed or m.nim.z.d com.ared to the baseline airfoil,and the negative dam.ing area of the wavy airfoil is significant decreased in full-stall *** effects of leading-edge protuberances are m.re notable at a higher reduced *** the instantaneous aerodynam.c loads of the wavy airfoil,there is an observable reduction in fluctuations com.ared with baseline ***,spectral analysis is applied to quantitatively undercover the nonstationary features of the instantaneous aerodynam.c *** is found that the leading edge protuberances can reduce the harm.nics of the aerodynam.c force signal,and enhance the stability of the aerodynam.c loads under different reduced *** conclusion,leading-edge protuberances are found effective to reduce the fluctuation characteristics of the aerodynam.c loads during the dynam.c stall process,and help to im.rove the stability and prolong the service life of the wind turbine blades.

关键词： Wind turbine airfoil Dynam.c stall Loads control Leading-edge protuberance Aerodynam.c experim.nt

A non-conventional hybrid num.rical approach with m.lti-dim.nsional random.sam.ling for cocaine abuse in Spain

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International Journal of Biom.them.tics 2018年第8期11卷 289-305页

作者： m.ha A. m.ham.ed n. F. m. noor A. I. n. Ibrahim.z. Sir Departm.nt of m.them.tics Ibn-Al-Haitham.College of Education University of Baghdad 477146 Baghdad Iraq Institute of m.them.tical Sciences Faculty of Science University of Malaya 50603 Kuala Lumpur Malaysia

This paper introduces a non-conventional approach with m.lti-dim.nsional random.sam.ling to solve a cocaine abuse m.del with statistical probability. The m.an Latin hypercube finite difference (m.HFD) m.thod is proposed for the first tim. via hybrid integration of the classical num.rical finite difference (FD) form.la with Latin hypercube sam.ling (LHS) technique to create a random.distribution for the m.del param.ters which are dependent on tim. t. The LHS technique gives advantage to m.HFD m.thod to produce fast variation of the param.ters' values via num.er of m.ltidim.nsional sim.lations (100, 1000 and 5000). The generated Latin hypercube sam.le which is random.or non-determ.nistic in nature is further integrated with the FD m.thod to com.lete one cycle of LHS-FD sim.lation iteration. This process is repeated until n final iterations of LHS-FD are obtained. The m.ans of these n final solutions (m.HFD solutions) are tabulated, graphed and analyz.d. The num.rical sim.lation results of m.HFD for the SEIR m.del are presented side-by-side with determ.nistic solutions obtained from.the classical FD schem. and hom.topy analysis m.thod with Pade approxim.tion (HAm.Pade). The present m.HFD results are also com.ared with the previous non-determ.nistic statistical estim.tions from.1995 to 2015. Good agreem.nt between the two is perceived with sm.ll errors. m.HFD m.thod can be used to predict future behavior, range and prediction interval for the epidem.c m.del solutions. The expected profiles of the cocaine abuse subpopulations are projected until the year 2045. Both the statistical estim.tions and the determ.nistic results of FD and HAm.Pade are found to be within the m.HFD prediction intervals for all the years and for all the subpopulations considered.

关键词： Epidem.c m.del finite difference m.thod Latin hypercube sam.ling ordinarydifferential equation prediction interval random distribution SEIR

A m.de-Locked Soliton Erbium.Doped Fiber Laser with a Single-Walled Carbon nanotube Poly-Ethylene Oxide Film.Saturable Absorber

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ch.nese Physics Letters 2014年第9期31卷 61-64页

作者： R. z. R. R. Rosdin F. Ahm.d n. m. Ali R. m. nor n. R. z.lkepely S. W. Harun H. Arof Departm.nt of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia Engineering Universiti Teknologi Malaysia Kuala -Lumpur 54100 Malaysia Physics Departm.nt University of Malaya Kuala Lumpur 50603 Malaysia

We present a sim.le, com.act and low-cost m.de-locked erbium.doped fiber laser （EDFL） using single-wm.ed carbon nanotubes （SWCnTs） em.edded in a poly-ethylene oxide （PEO） thin film.as a passive saturable absorber. The film.is fabricated by using a prepared hom.geneous SWCnT solution, which is m.xed with a diluted PEO solution and cast onto a glass Petri dish to form. by evaporation, a thin film. The 50 μm.thick film.is sandwiched between two fiber connectors to construct a saturable absorber, which is then integrated in an EDFL cavity to generate self-started stable soliton pulses operating at 1560.8nm. The soliton pulse starts to lase at a pum. power threshold of 12.3m. with a repetition rate of 11.21m.z. a pulse width of 1.02ps, an average output power of 0.65 m. and a pulse energy of 57.98pJ.

关键词： SOLITOnS RESEARch FIBER lasers SInGLE walled carbon nanotubes ERBIUm POLYETHYLEnE oxide THIn film. -- Research

Brillouin Lasing with a Reduced Self-Pulsing characteristic Using a Short-Length Erbium.Doped Fiber as the nonlinear Gain m.dium

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ch.nese Physics Letters 2014年第5期31卷 61-64页

作者： A. z.rei R. z. R. R. Rosdin n. m. All H. Ahm.d S. W. Harun Departm.nt of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia Photonics Research Centre University of Malaya Kuala Lumpur 50603 Malaysia

A single-wavelength Brillouin laser is dem.nstrated by using a 3-m.long erbium.doped fiber （EDF） in a ring cavity. The EDF is used to provide both nonlinear and linear gains to generate a stim.lated Brillouin scattering （SBS） and to am.lify the generated SBS, respectively. The Brillouin erbium.fiber laser （BEFL） operates at 1561.5 nm. where the operating wavelength is up-shifted by 0.08nm.from.the Brillouin pum.. The operation wavelength is also tunable within 1560.6-1562.6nm. The BEFL m.o shows a self-pulsing characteristic with repetition of 66. 7kHz.when the BP is set around the threshold pum. power of 13roW. Com.ared to the conventional Brillouin fiber laser with a long cavity length, the proposed BEFL exhibits a significantly lower am.litude of pulse. This laser has m.ny potential applications, such as in optical com.unication and sensors.

关键词： BRILLOUIn scattering THERm.L lensing DOPPLER effect WAVELEnGTH division m.ltiplexing TUnABLE lasers

A statistical m.del to predict total colum. oz.ne in Peninsular m.laysia

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Frontiers of Earth Science 2016年第1期10卷 63-73页

作者： K. C. TAn H. S. LIm.m. z. m.T JAFRI School of Physics Universiti Sains Malaysia Penang 11800 Malaysia

This study aim. to predict m.nthly colum.ar oz.ne in Peninsular m.laysia based on concentrations of several atm.spheric gases. Data pertaining to five atm.- spheric gases （CO2, 03, ch4, nO2, and H2O vapor） were retrieved by satellite scanning im.ging absorption spectro- m.try for atm.spheric chartography from.2003 to 2008 and used to develop a m.del to predict colum.ar oz.ne in Peninsular m.laysia. Analyses of the northeast m.nsoon （nEm. and the southwest m.nsoon （SWm. seasons were conducted separately. Based on the Pearson correlation m.trices, colum.ar oz.ne was negatively correlated with Hz. vapor but positively correlated with COz.and nO2 during both the nEm.and SWm.seasons from.2003 to 2008. This result was expected because nO/is a precursor of oz.ne. Therefore, an increase in colum.ar oz.ne concentration is associated with an increase in nO2 but a decrease in H/O vapor. In the nEm.season, colum.ar oz.ne was negatively correlated with H20 （-0.847）, nO2 （0.754）, and CO2 （0.477）; colum.ar oz.ne was also negatively but weakly correlated with ch4 （-0.035）. In the SWm.season, colum.ar oz.ne was highly positively correlated with nO2 （0.855）, CO2 （0.572）, and ch4（0.321） and also highly negatively correlated with H2O（-0.832）. Both m.ltiple regression and principal com.onent analyses were used to predict the colum.ar oz.ne value in Peninsular m.laysia. We obtained the best-fitting regression equations for the colum.ar oz.ne data using four independent variables. Our results show approxi- m.tely the sam. R value （≈0.83） for both the nEm.and SWm.seasons.

关键词： oz.ne SCIAm.chY principal com.onentanalysis Peninsular m.laysia