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Applied Mathematics and Mechanics(English Edition) 2021年第12期42卷 1787-1798页

作者： t.HAYAt k.MUHAMMAD A.AlSAEDI department of mathematics quaid-i-azam universityislamabad 44000pakistan nonlinear analysis and applied mathematics(naam)research group department of mathematicsfaculty of scienceking abdulaziz universityjeddah 80203saudi arabia

the melting phenomenon in two-dimensional(2 D)flow of fourth-grade material over a stretching surface is *** flow is created via a stretching surface.A Darcy-Forchheimer(D-F)porous medium is considered in the flow *** heat transport is examined with the existence of the Cattaneo-Christov(C-C)heat *** fourth-grade material is electrically conducting subject to an applied magnetic *** governing partial differential equations(PDEs)are reduced into ordinary differential equations(ODEs)by appropriate *** solutions are constructed analytically through the optimal homotopy analysis method(OHAM).the fluid velocity,temperature,and skin friction are examined under the effects of various involved *** fluid velocity increases with higher material parameters and velocity ratio parameter while decreases with higher magnetic parameter,porosity parameter,and Forchheimer *** fluid temperature is reduced with higher melting parameter while boosts against higher Prandtl number,magnetic parameter,and thermal relaxation ***,the skin friction coefficient decreases against higher melting and velocity ratio parameters while increases against higher material parameters,thermal relaxation parameter,and Forchheimer number.

关键词： melting heat Darcy-Forchheimer(D-F)porous medium magnetohydrodynamics(MHD) Cattaneo-Christov(C-C)heat flux fourth-grade fluid optimal homotopy analysis method(OHAM)

Effect of Injection Position on In-Flight Melting Behavior of Granular Alkali-Free Glass Raw Material in 12-Phase AC Arc Plasma

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Plasma Science and technology 2009年第6期11卷 699-703页

作者：姚耀春 k.YAtSUDA t.WAtANABE t.YANO National Engineering laboratory of Vacuum Metallurgy Kunming University of Science and Technology Department of Environmental Chemistry and Engineering Tokyo Institute of TechnologyYokohama 226-8502Japan Department of Chemistry and Materials Science Tokyo Institute of TechnologyTokyo 152-8550Japan

An innovative in-flight glass melting technology with a multi-phase AC arc plasma was developed to save energy and reduce emissions for the glass industry. the effect of the injection position on the in-flight melting behavior of granulated powders was investigated. Results show that the injection position has a strong effect on the melting behavior of alkali-free glass raw material. With the increase in injection distance, the vitrification, decomposition, and particle shrinkage of initial powders are improved. longer injection distance causes much energy to transfer to particles due to a longer residence time of powder in the high temperature zone. the high vitrification and decomposition degrees indicate that the new in-flight melting technology with 12-phase AC arc can substantially reduce the melting and refining time for glass production.

关键词： 12-phase AC arc plasma in-flight melting technology heat transfer glass production

Minimization of Reactive Power Fluctuation in Jt-60SA Magnet Power Supply

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Plasma Science and technology 2013年第2期15卷 184-187页

作者： k. SHIMADA t. tERAkADO k. YAMAUCHI M. MAtSUkAWA O. BAUlAIGUE R. COlEttI A. COlEttI l. NOVEllO Japan Atomic Energy Agency 801-1 Mukoyama Naka Ibaraki 311-0193 Japan CEA IRFMF-13108 Saint-Paul-Lez-Durance France ENEA 1-00044 Frascati Rome Italy Fusion for Energy Boltzmannstr 2Garching 85748 Germany

this paper describes an asymmetric control method for the firing angle and a start/stop timing shift control of four thyristor converters called ＂Booster PS＂ to minimize the reactive power fluctuation during plasma initiation in Jt-60SA. From the simulation using the ＂PSCAD/EMtDC＂ code, it is found that these control methods can drastically reduce the reac- tive power induced by the four units of the ＂Booster PS＂. In addition, the voltage fluctuation of the motor-generator connected to the ＂Booster PS＂ is expected to be suppressed. this can also contribute to achieve stable control of the Jt-60SA magnet power supplies.

关键词： Jt-60SA power supply poroidal field coil reactive power fluctuation asym-metric control PSCAD/EMtDC

Mechanical Property Prediction of Commercially Pure titanium Welds with Artificial Neural Network

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Journal of Materials Science & technology 2005年第3期21卷 403-407页

作者： YanhongWEI k.k.D.H.Bhadeshia t.Sourmail StatekeylaboratoryofAdvancedWeldingProductiontechnology HarbinInstituteofTechnologyHarbin150001China DepartmentofMaterialsScienceandMetallurgy UniversityofCambridgeCambridgeCB23QZUK

Factors that affect weld mechanical properties of commercially pure titanium have been investigated using artificial neural networks. Input data were obtained from mechanical testing of single-pass, autogenous welds, and neural network models were used to predict the ultimate tensile strength, yield strength, elongation, reduction of area, Vickers hardness and Rockwell B hardness. the results show that both oxygen and nitrogen have the most significant effects on the strength while hydrogen has the least effect over the range investigated. Predictions of the mechanical properties are shown and agree well with those obtained using the 'oxygen equivalent' (OE) equations.

关键词： Commercially pure titanium Artificial neural networks Mechanical properties Weld

Direct joining of oxygen-free copper and carbon-fiber-reinforced plastic by friction lap joining

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Journal of Materials Science & technology 2018年第1期34卷 192-197页

作者： l.H. Wu k. Nagatsuka k. Nakata Joining and Welding Research Institute Osaka University 11-1 Mihogaoka Ibaraki Osaka 567-0047 Japan

Oxygen-flee copper （Cu） was successfully joined to carbon-fiber-reinforced thermoplastic （CFRtP, polyamide 6 with 20wt% carbon fiber addition） by friction lap joining （FlJ） at joining speeds of 200-1600 mm/min with a constant rotation rate of 1500 rpm and a nominal plunge depth of 0.9 ram. It is the first time to report the joining of CFRtP to Cu by FlJ. As the joining speed increased, the tensile shear force （tSF） of joints increased first, and decreased thereafter. the maximum tSF could reach 2.3 kN （ 15 mm in width）. Hydrogen bonding formed between the amide group of CFRtP and the thin Cu20 layer on the Cu surface, which mainly contributed to the joint bonding. the influence factors of the tSF of the joints at different joining speeds were discussed. the tSF was mainly affected by the joining area, the degradation of the plastic matrix and the number and the size of bubbles. As the joining speed increased, the influence factors varied as follows： the joining area increased first and then decreased; the degra- dation of the plastic matrix and the number and the size of bubbles decreased. the maximum tSF was the comprehensive result of the relatively large joining area, small degradation of the plastic matrix and small number and sizes of bubbles.

关键词： Friction lap joining Metal Plastic Carbon-fiber reinforced thermoplastic Dissimilar materials joining

How do quantum numbers generally vary in the adiabatic transformation of an ideal gas?

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Chinese Physics B 2011年第10期20卷 305-311页

作者： t. Yarman A. l. kholmetskii Department of Engineering Okan UniversityAkfirat Istanbul Turkey & Savronik Eskisehir Turkey Department of Physics Belarus State University4 Nezavisimosti Avenue 220030 Minsk Belarus

We continue to analyse the known law of adiabatic transformation for an ideal gas PV5/3=Constant, where P isthe pressure and V is the volume, and following the approach of non-relativistic quantum mechanics which we suggested in a previous work （Yarman et al. 2010 Int. J. Phys. Sci. 5 1524）. We explicitly determine the constant for the general parallelepiped geometry of a container. We also disclose how the quantum numbers associated with molecules of an ideal gas vary through an arbitrary adiabatic transformation. Physical implications of the results obtained are discussed.

关键词： ideal gas adiabatic transformation non-relativistic quantum mechanics

Influence of local stiffeners and cutout shapes on the vibration and stability characteristics of quasi-isotropic laminates under hygro-thermo-mechanical loadings

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Defence technology（防务技术） 2022年第12期18卷 2107-2124页

作者： t.Rajanna k.S.Subash Chandra k.Venkata Rao Department of Civil Engineering B.M.S College of EngineeringBengaluru560019India Research Scholar B.M.S College of EngineeringBengaluru560019India Department of Mechanical Engineering B.M.S Evening College of EngineeringBengaluru560019India Department of Mechanical Engineering Government PolytechnicBagepalli561207India

the perforated stiffened panel is generally found as a sub-component of sophisticated *** fundamental purpose of this panel is to withstand against buckling under complicated loading and environmental ***,an accurate knowledge of critical buckling behaviour of stiffened panels is very much essential for a reliable and lightweight structural *** this paper,the focus is on quasi-laminated panels with different cutout shapes of various sizes and their responses to hygrothermal environments under nonlinearly varying edge loads and is compared with the locally stiffened *** this,the modelling of the panel and stiffener is done by adopting nine-noded heterosis plate elements and three noded beam elements *** stiffener formulation is suitably modified in order to take the torsional effect also into consideration along with the effect of shear ***,the plate and the stiffener elements are treated separately,and then the displacement compatibility is maintained between them by using the transformation *** a given loading and geometric discontinuity,the stress distribution within the perforated panel is highly non-uniform in nature and hence a dynamic approach has been used to calculate buckling loads by adopting two sets of boundary conditions,one set for pre-buckling stress analysis and the second set for buckling *** different quasi-isotropic stacking sequences are deliberated in this work by varying different ply-orientation in each *** study also addresses the effect of various parameters such as nonlinear loads,hygro-thermal loads,cutout size and shapes,position of cutout,stiffener parameters,stacking sequences,thickness of plate and boundary conditions.

关键词： locally stiffened panels Buckling Vibration Cutouts Heterosis Hygrothermal environment

Achieving superior mechanical properties in friction lap joints of copper to carbon-fiber-reinforced plastic by tool offsetting

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Journal of Materials Science & technology 2018年第9期34卷 1628-1637页

作者： l.H.Wu k.Nagatsuka k.Nakata Joining and Welding Research Institute Osaka University

It is a challenge to achieve a sound welded metal/carbon-fiber-reinforced thermoplastic（CFRtP） joint with high strength and few bubbles. In this study, sound lap joints of Cu and CFRtP were obtained by friction lap joining（FlJ） directly at rotation rates of 600-2000 rpm, with the welding tool at the joint center and offsetting the tool 7 mm away from the center toward the retreating side, respectively. tool offsetting reduced the non-uniform temperature distribution in the lap joints resulting from the high conductivity of Cu, which not only enhanced the tensile shear force from 0.89-2.25 kN to 1.71-3.54 kN,with the maximum increasing rate of 135%, but also reduced the bubble area to only 19% of the original level of 2000 rpm. It is the first time to report a high-quality Cu/CFRtP joint with a high strength and few bubbles. the large increase of the strength after tool offsetting was attributed to the increase of the joining area, the decrease of bubbles and the decrease of the CFRtP degradation. the details on the generation,quantitative distribution and expulsion of the bubbles in the FlJ joints were discussed.

关键词： Hybrid joining Plastic Metal Carbon-fiber-reinforced plastic Properties

the ecological validity of traditional standing and novel bicycle balance and agility tests for predicting performance in mountain bikers

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Sports Medicine and Health Science 2022年第4期4卷 287-292页

作者： k.Buchholtz M.lambert t.l.Burgess Health Physical ActivityLifestyleand Sport(HPALS)Research CentreUniversity of Cape TownCape TownSouth Africa Department of Physiotherapy LUNEX International University of HealthExercise and SportsLuxembourg Division of Physiotherapy University of Cape TownAnzio RoadObservatoryCape TownSouth Africa Centre for Medical Ethics and law Faculty of Medicine and Health SciencesStellenbosch UniversityCape TownSouth Africa

Falls are a common mechanism of injury in mountain biking and may be related to a loss of control of the ***,the components of bicycle control(balance and agility)are measured in standing and running,which may not reflect the skills required in mountain *** this paper,we present the validity of both traditional standing and novel bicycle-specific balance tests in mountain ***-nine male and female participants completed indoor laboratory tests and an outdoor downhill *** completed single-leg stance balance,Y-balance test,one static and four dynamic bicycle-specific balance tests,a bicycle agility test,and an outdoor downhill ***-leg stance balance and Y-balance tests with eyes open had poor validity when associated with bicycle *** static(r=-0.57,p=0.001)and four dynamic bicycle balance tests(r=-0.51 to-0.78,p=0.005 to 0.0001),and the bicycle agility test(r=0.87,pte to strong relationships with the outdoor downhill ***-leg stance balance and Y-balance tests with eyes open are not valid measures of performance on a mountain bike,and should not be used to assess these *** novel bicycle balance tests have adequate validity to be used as measures of performance in mountain bikers.

关键词： Bicycling Control Proprioception

tuning the particle size,physical properties,and photocatalytic activity of Ag_(3)PO_(4)materials by changing the Ag^(+)/PO_(4)^(3-)ratio

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Chinese Physics B 2023年第3期32卷 561-568页

作者： Hung N M Oanh l t M Chung D P thang D V Mai V t Hang l t Minh N V Center for Nano Science and technology Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Department of Physics Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Hanoi University of Mining and Geology Duc Thang WardNorth Tu Liem DistrictHanoi 100000Vietnam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoi 100000Vietnam Faculty of Basic Sciences Hanoi University of Natural Resources and Environment41 A Phu Dien RoadNorth Tu LiemHanoi 100000Vietnam

this study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocatalyst that is fabricated,using a facile precipitation method,from AgNO_(3)and Na2HPO_(4)·12H_(2)*** material characterizations were carried out using x-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive x-ray spectroscopy(EDX),Brunauer–Emmett–teller(BEt)surface area,Fourier transform infrared(FtIR)absorption,Raman scattering,x-ray photoelectron spectroscopy(XPS),UV-vis absorption,and photoluminescence(Pl).the results show that Ag_(3)PO_(4)crystallizes better when the excess PO_(4)^(3-)content increases,and the lattice parameters decrease slightly,while the crystal diameter and the particle size *** change is also observed in the Raman scattering and FtIR spectra with the increase in the vibration frequency of the[PO_(4)]*** compression of the[PO_(4)]unit was also confirmed in the XPS spectra with the shift of P 2p peaks toward higher binding *** photocatalytic results showed that the samples synthesized from excess PO_(4)^(3-)solution exhibited higher photocatalytic performance compared to the sample with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.A sample prepared from the precursor solution with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.5 was optimal for RhB decomposition under both visible light and natural sunlight,completely decomposing 10 ppm RhB after 15 minutes of xenon lamp irradiation and after 60 minutes under solar light *** is attributed to the high crystallinity,small particle size and low electron–hole recombination rate of the sample.

关键词： morphology photocatalytic Ag^(+)/PO_(4)^(3-)ratio visible light