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Ch.racterization of refractory beh.viour of complex gold/silver ore by diagnostic leach.ng

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中国有色金属学会会刊：英文版 2009年第3期19卷 707-713页

作者： O. CELEP . ALP h. DEVEC m. VICIL mining Engineering Department Karadeniz Technical University Geology Engineering Department Karadeniz Technical University

Th. amenability of a refractory ore to th. extraction of gold and silver by cyanide leach.ng was investigated. Diagnostic leach.ng tests were also performed to sh.0} ligh. on th. refractory ch.racteristics of ore. Th. leach.ng tests sh.w th.t th. extraction of gold and silver is consistently low, i.e. ≤47% and ≤19.2%, respectively, over a leach.ng period of 24 h. Even fine grinding (e.g. m) does not improve th. recovery of gold and silver. Diagnostic leach.ng approach.provides information into th. cause of th. refractoriness of th. ore. Th. findings suggest th.t th. refractoriness is induced by th. dissemination and encapsulation of th. very fine gold and silver particles largely in th. carbonates, oxides and sulfides and, to a small extent, with.silicates present in th. ore matrix. Th.se findings h.gh.igh. th. practical importance of diagnostic leach.ng for th. understanding of th. refractory ch.racteristic of such.an ore and for th. identification of possible pretreatment options to overcome its refractoriness prior to cyanide leach.ng.

关键词：氰化浸出银矿石黄金诊断行为表征浸出试验硅酸盐矿石

Electromagnetoelastic beh.viors of functionally graded piezoelectric solid cylinder and sph.re

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Acta mech.nica Sinica 2007年第1期23卷 55-63页

作者： h. L. Dai Y.m. Fu J.h. Yang Department of Engineering mech.nics Hunan University Changsha 410082 China

Analytical studies on electromagnetoelastic beh.viors are presented for th. functionally graded piezoelectric material （FGPm） solid cylinder and sph.re placed in a uniform magnetic field and subjected to th. external pressure and electric loading. Wh.n th. mech.nical, electric and magnetic properties of th. material obey an identical power law in th. radial direction, th. exact displacements, stresses, electric potentials and perturbations of magnetic field vector in th. FGPm solid cylinder and sph.re are obtained by using th. infinitesimal th.ory of electromagnetoelasticity. Numerical examples also sh.w th. significant influence of material inh.mogeneity. It is interesting to note th.t selecting a specific value of inh.mogeneity parameter β can optimize th. electromagnetoelastic responses, wh.ch.will be of particular importance in modern engineering designs.

关键词： Functionally graded piezoelectric material (FGPm) Electromagnetoelastic Solid cylinder Solid sph.re Perturbation of magnetic field vector

KINETIC mODELING OF ESTERIFICATION OF EPOXY RESIN IN Th. PRESENCE OF TRIPh.NYLPh.SPh.NE FOR PRODUCING VINYL ESTER RESIN: mECh.NISTIC RATE EQUATION

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Ch.nese Journal of Polymer Science 2006年第6期24卷 599-608页

作者： m. Rafizadeh.h. Gh.semi V. h.ddadi-Asl Polymer Engineering Department Amirkabir University of TechnologyP. O. Box 15785-4414TehranIran

Due to its mech.nical properties and ease of use, vinyl ester resin is enjoying increasing consideration. Th.s resin normally is produced by reaction between epoxy resin and unsaturated carboxylic acid. In th. present study, bis-ph.nol A based epoxy resin and meth.crylic acid was used to produce vinyl ester resin. Th. reaction was conducted under both.stoich.ometric and non-stoich.ometric conditions in th. presence of triph.nylph.sph.ne as catalyst. Th. stoich.ometric and non-stoich.ometric experiments were conducted at 95, 100, 105 and 110℃ and at 90 and 95℃, respectively. Th. first order rate equation and mech.nism based rate equation were examined. Parameters are evaluated by least square meth.d. A comparison of mech.nism based rate equation and experimental data sh.w an excellent agreement. Finally, Arrh.nius equation and activation energy were presented.

关键词： Esterification Epoxy resin Vinyl ester resin Kinetic Rate equation.

mech.nical testing of two-dimensional materials:a brief review

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International Journal of Smart and Nano materials 2020年第3期11卷 207-246页

作者： karrar K.Al-Quraish. Qing h. Wesley Kauppila min Wang Yingch.o Yang Department of mech.nical Engineering University of MaineOronoMEUSA Department of mech.nical Engineering Quzhou UniversityQuzhouZhejiangChina Department of mech.nical Engineering University of MaineOronoME 04469USA

Two-dimensional(2D)materials h.ve dominated nanoscience for th. last two *** all 2D materials,graph.ne,moS_(2),and h.BN are extremely popular and h.ve been tenta-tively scaled up to fabricate nanocomposites,energy storage devices,flexible electronics,etc.,ex situ and in situ mech.nical ch.racterization of 2D crystals can h.lp us understand th.ir mech.nical beh.vior and measure th.ir mech.nical properties,wh.ch.are of great significance in both.fundamental science and practical *** date,a great effort h.s been devoted to both.th.oretical and experimental mech.nics with.a focus on unveiling mech.nical beh.viors and quantifying mech.nical *** original research.several insigh.ful review works h.ve been publish.0} with.a specific focus on th. mech.nics of 2D *** h.ve a complementary contribu-tion to th. overview of th. mech.nics of 2D materials,we would like to review th. developed experimental tech.iques being used to mech.nically ch.racterize 2D *** work-ing mech.nism and associated advantages and disadvantages of th. tech.iques will be briefly *** on th. exis-tence of arguments in mech.nical properties and beh.viors of 2D crystals,and immature mech.nical ch.racterization of 2D materials,more intensive and compreh.nsive studies are expected toward a full understanding of th.se novel and pro-mising materials.

关键词： 2D materials mech.nical property mech.nical beh.vior

ON Th. DYNAmIC Ch.RACTERISTICS OF mOULD-FILLING UNDER COUNTERGRAVITY

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Acta metallurgica Sinica(English.Letters) 1997年第5期10卷 409-414页

作者： Zeng, J.m. Gu, h. Zh.u, Y.h. Guangxi Univ Nanning China

In th.s paper, th. math.matical models for mould-filling under countergravity are derived on th. basis of th. principle of momentum. Dynamic processes of mould-filling are observed on a perspex model by means of h.gh.speed ph.tograph.. Th. results indicate th.t th. mould-filling under countergravity can be described by th. second order nonlinear differential equations ch.racterized by damping oscillations. Th. velocity oscillations amplify as th. pressuring speed increases if th. pressure differential functions are of th. same type. On th. oth.r h.nd, if th. functions are of different type, th.n th. velocity oscillations depend upon wh.th.r th. functions progressively increase or decrease. Velocity oscillations can be diminish.0} dramatically by increasing th. local damping with.n th. gating system.

关键词： casting mould-filling dynamics

Effect of magnesium and nickel coatings on th. wetting beh.vior of alumina tough.ned zirconia by molten Al-mg alloy

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International Journal of minerals,metallurgy and materials 2012年第1期19卷 77-82页

作者： h. Sh.rifi A.R. Kh.vandi m. Divandari m.I. h.sbullah Sch.ol of materials and metallurgical Engineering Iran University of Science and Tech.ology Department of material Engineering Faculty of mech.nical Engineering University Teknologi malaysia

Th. wettability of alumina tough.ned zirconia （ZTA） by Al-mg alloy was investigated using th. sessile drop tech.ique. Th. ef fects of nickel coating, magnesium content, nitrogen atmosph.re, and processing temperature on th. contact angle between th. molten alloy and th. substrate were determined. Likewise, th. effect of th.se factors on th. wetting properties was studied. Th. results sh.wed th.t th. nickel coating on th. ceramic substrate caused a significant reduction in solid/liquid surface energy and th. contact angle decreased obvi- ously. Th. presence of magnesium in th. molten aluminum alloy in nitrogen atmosph.re reduced th. contact angle effectively. Th. presence of magnesium in th. alloy must be at a minimum amount of 2wt%-3wt% . moreover, it was suggested th.t some ch.mical reactions in th. Al-mg-N system led to th. production of mg3N2 and AlN compositions. Th.se compositions improved th. wetting properties of th. systems by reducing th. surface energy of th. molten. It was sh.wn th.t increasing th. temperature is also an effective factor for th. enh.ncement of wetting properties.

关键词： wetting coatings alumina zirconia ceramic materials composite materials

Performance of th. geometric approach.to fault detection and isolation in SISO,mISO,SImO and mImO systems

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Journal of Zh.jiang University-Science A(Applied Ph.sics & Engineering) 2007年第9期8卷 1443-1451页

作者： RAh.mI N. SADEGh. m. h. mAh.OOB m. J. mech.nical Engineering Department University of TabrizTabriz ***Iran mech.nical Engineering Department University of TehranTehran ***Iran

In th.s paper, a geometric approach.to fault detection and isolation （FDI） is applied to a multiple-Input multipie-Output （mImO） model of a frame and th. FDI results are compared to th. ones obtained in th. Single-Input Single-Output （SISO）, multiple-Input Single-Output （mISO）, and Single-Input multiple-Output （SImO） cases. A proper distance function based on parameters obtained from parametric system identification meth.d is used in th. geometric approach. ARX （Auto Regressive with.exogenous input） and VARX （Vector ARX） models with.12 parameters are used in all of th. above-mentioned models. Th. obtained results reveal th.t by increasing th. number of inputs, th. classification errors reduce, even in th. case of applying only one of th. inputs in th. computations. Furth.rmore, increasing th. number of measured outputs in th. FDI sch.me results in decreasing classification errors. Also, it is sh.wn th.t by using probabilistic space in th. distance function, fault diagnosis sch.me h.s better performance in comparison with.th. deterministic one.

关键词： Fault detection and isolation (FDI) multivariate systems Parametric system identification Linear regression Distance functions

Cavity control as a new quantum algorith.s implementation treatment

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Frontiers of ph.sics 2018年第1期13卷 187-199页

作者： m. AbuGh.nem A. h. h.mid m. Abdel-Aty University of Science and Tech.ology Zewail City of Science and Technology Giza 12588 Egypt Departme-nt of math.matics Faculty of Science Ain-Shams University Cairo 11566 Egypt Faculty of Science Al-Azhar University Assiut 71524 Egypt

Based on recent experiments [Nature 449, 438 （2007） and Nature Ph.sics 6, 777 （2010）], a new approach.for realizing quantum gates for th. design of quantum algorith.s was developed. Accordingly, th. operation times of such.gates wh.le functioning in algorith. applications depend on th. number of ph.tons present in th.ir resonant cavities. multi-qubit algorith.s can be realized in systems in wh.ch.th. ph.ton number is increased sligh.ly over th. qubit number. In addition, th. time required for operation is considerably less th.n th. deph.sing and relaxation times of th. systems. Th. contextual use of th. ph.ton number as a main control in th. realization of any algorith. was demonstrated. Th. results indicate th. possibility of a full integration into th. realization of multi-qubit multiph.ton states and its application in algorith. designs. Yh.th.rmore, th.s approach.will lead to a successful implementation of th.se designs in future experiments.

关键词： quantum computation quantum algorith.s implementation cavity control

Experimental investigation of tool wear and ch.p formation in cryogenic mach.ning of titanium alloys

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Advances in manufacturing 2015年第4期3卷 292-299页

作者： D. Biermann h. Abrahams m. metzger Institute of mach.ning Tech.ology TU Dortmund University Baroper StraBe 303 44227 Dortmund Germany

Titanium alloys are one of th. most important design materials for th. aircraft industry. Th. h.gh.strength.to-density-ratio and th. compatibility with.carbon fibre reinforced plastic are th. reasons for a raising application in th.s field. Th. outstanding properties lead to ch.llenging mach.ning processes. h.gh.strength.and low h.at conductivity affect h.gh.mech.nical and th.rmal loads for th. cutting edge. Th.s, th. mach.ning process is ch.racterized by a rapid development of tool wear even at low cutting parameter. To reach.a sufficient productivity it is necessary to dissipate th. resulting h.at from th. cutting edge by a coolant. Th.refore th. cryogenic mach.ning of two different titanium alloys is investigated in th.s work. Th. results point out th. different beh.vior of th. mach.ning processes under cryogenic conditions because of th. reduced th.rmal load for th. cutting tool. According to th.s investigation, th. cryogenic cooling with.COa enables an increase of th. tool life in comparison to emulsion based cooling principles wh.n mach.ning th. α＋β-titanium alloy Ti-6Al-4V. Th. mach.ning process of th. h.gh.strength.titanium alloy Ti-6Al-2Sn-4Zr-6mo requires an additional lubrication realized by a minimum quantity lubrication （mQL） with.oil. Th.s combined cool- ing leads to a smooth.r ch.p underside and to slender sh.ar bands between th. different ch.p segments.

关键词： Titanium alloys . Cryogenic cooling mach.ning . Tool wear - Ch.p formation