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Laser Induced f.uorescence Spectroscopy of.IrN

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Ch.nese Journal of.Ch.mical Ph.sics 2009年第2期22卷 157-161页

作者： h. f. Pang A. S. C. Ch.ung Department of.Ch.mistry The University of Hong Kong Pokfulam Road Hone Kong China

h.gh.resolution laser induced f.uorescence, spectra of.IrN in th. spectral region between 394 and 520 nm were recorded using laser vaporization/reaction f.ee jet expansion and laser induced f.uorescence spectroscopy. Seven new vibronic transition bands were observed and analyzed. Two Ω=1 and f.ve Ω=0 new states were identif.ed. Least squares f.t of.rotationally resolved transition lines yielded accurate molecular constants f.r th. upper states. Spectra of.isotopic molecules were observed, wh.ch.provided conf.rmation f.r th. vibrational assignment. Comparison of.th. observed electronic states of.IrB, IrC, and IrN provides a good understanding of.th. ch.mical bonding of.th.s group of.molecules.

关键词： Electronic transition Rotational analysis Iridium mononitride Laser induced f.uorescence spectroscopy

Robust switch.d f.actional controller f.r perf.rmance improvement of.single ph.se active power f.lter under unbalanced conditions

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f.ontiers in Energy 2016年第2期10卷 203-212页

作者： h. Af.h.UL f. KRIM D. Ch.KOUCh. A. BEDDAR LASS Laboratory Electronics Department Technology faculty University Mohamed Boudiaf of M'sila BP.166 Route Ichebilia M'sila28000 Algeria LEPCI Laboratory Electronics Department University of Ferhat AbbasSetif-1 route de B6jaia Setif 19000 Algeria Department of.Electrical Engineering Technology faculty SkikdaUniversity Skikda 21000 Algeria

A novel controller is proposed to regulate th. DC-link voltage of.a single ph.se active power f.lter （SPAPf.. Th. proposed switch.d f.actional controller （Sf.） consists of.a conventional PI controller, a f.actional order PI （f.-PI） controller and a decision maker th.t switch.s between th.m. Commonly, th. conventional PI controller is used in regulation loops due to its advantages in steady-state but it is limited in transient state. On th. oth.r h.nd, th. f.-PI controller overcomes th.se draw- backs but it causes dramatic degradation in control perf.rmances in steady-state because of.th. f.actional calculus th.ory and th. approximation meth.d used to implement th.s kind of.controller. Th.s, th. purpose of.th.s paper is to switch.to th. PI controller in steady-state to obtain th. best power quality and to switch.to th. f.-PI controller wh.n external disturbances are detected to guarantee a f.st transient state. To investigate th. ef.iciency and accuracy of.th. Sf. considering all robustness tests, an experimental setup h.s been establish.d. Th. results of.th. Sf. f.lf.ll th. requirements, conf.rm its h.gh.perf.rmances in steady and transient states and demon- strate its f.asibility and ef.ectiveness. Th. experiment results h.ve satisf.ed th. limit specif.ed by th. IEEE h.rmonic standard 519.

关键词： conventional PI controller f.actional calculus(f.) total h.rmonic distortion (Th.) Oustaloup contin-uous approximation (OCA) single ph.se active power f.lter(SPAPf.

STUDY ON h.T SAND COOLING EQUIPMENT WITh.DAMPING SAND CASCADE AND VERTICAL SPOUTED-f.UIDIZED BED

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Acta Metallurgica Sinica(English.Letters) 2005年第5期18卷 669-673页

作者： L. C. wang f. wang X.h. You Department of.Material Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 China

A new kind of.h.t sand cooling equipment with.vertical spouted-f.uidized bed is developed in th.s paper. It is similar to th. traditional h.rizontal vibrating f.uidized boiling cooler in principle but dif.erent f.om it in structure. Th. processing principle of.th. cooler is analyzed. Th. inf.uence of.main structural and processing parameters on th. cooling ef.ect and its mech.nism are research.d. Oth.r ch.racteristics of.th. cooler are discussed also. Experiment results sh.w th.t th. cooling ef.iciency η is equal to or larger th.n 83%, th. temperature of.output sand is less th.n 40℃ with.th. temperature of.input sand is about between 80 and 90℃, and th. productivity is 5t/ （h.m）

关键词： h.t sand cooling f.uidized bed f.undry equipment

h.rmonic Oscillations in a Grid-Connected PV Generation f.rm Caused by an Increased Number of.Parallel-Connected PV Generating Units and Damping Controllers

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CSEE Journal of.Power and Energy Systems 2020年第6期10卷 2350-2359页

作者： Wenjuan Du Zh.ch.ng Ma Yang wang h. f. wang Sch.ol of.Electrical Engineering Sichuan University Chengdu China Electric Power Research.Institute State Grid Gansu Electric Power Co. Ltd. Lanzhou China

Th.s paper examines th. h.rmonic oscillations in a grid-connected PV generation f.rm (PVGf. caused by th. parallel connection of.an increased number of.PV generation units (PVGUs). An equivalent model of.th. grid-connected PVGf.is derived, wh.ch.clearly explains wh. th.re are internal and external oscillation modes in th. grid-connected PVGf. An indicator of.impedance multiplication (IIM) is proposed to quantitatively estimate th. impact of.th. increased number of.PVGUs in parallel connection. Th. analysis in th.s paper reveals th. mech.nism about wh. th. damping of.external oscillation modes may decrease wh.n more PVGUs are in parallel connection under th. condition th.t th. IIM is positive. An example grid-connected PVGf.is presented in th.s paper to demonstrate and evaluate th. derived analysis and conclusions. A meth.d f.r designing th. damping controllers to ensure a negative IIM is proposed. With.th. damping controllers being installed, th. risk of.growing h.rmonic oscillations caused by th. increased number of.th. PVGUs in parallel connection can be ef.ectively eliminated.

关键词： Oscillators Power system stability h.rmonic analysis Wind f.rms State-space meth.ds Power h.rmonic f.lters Power system dynamics

Ef.ect of.Radio f.equency Magnetron Sputtering Power on Structural and Optical Properties of.Ti6A14V Th.n f.lms

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Ph.tonic Sensors 2017年第2期7卷 163-170页

作者： Moh.mmed K. Kh.LAf.h. f. Al-TAAY Dawood S. ALI Ministry of.Science and Tech.ology Center of Applied Physics Baghdad Iraq Department of.Ph.sics College of Science for Women University of Baghdad Baghdad Iraq Department of.Ph.sics College of Education for Pure Sciences University of Anbar Anbar Iraq

In th.s research. th. ef.ects of.target sputtering power on th. structure and optical properties of.radio f.equency （Rf. sputtered Ti6A14V f.lms were investigated. Dif.erent sputtering Rf.powers were used to produce dif.erent th.cknesses of.Ti6A14V th.n f.lms, f.om th. X-ray dif.raction, it was f.und th.t th. Ti6A14V f.lms h.d polycrystalline cubic and h.xagonal structures and increased f.lms crystallinity and crystalline size with.increasing th. sputtering power. Atomic f.rces microscopy （Af.） gave us a nanometric f.lm ch.racter, f.lms h.mogeneity, and surf.ces rough.ess. A h.gh.r degree of.rough.ess and average grain size with.increasing Rf.power was exh.bited. Band gap and ref.active index of.Ti6A14V th.n f.lms varied with.sputtering Rf.powers.

关键词： Rf.magnetron sputtering Ti6A14V structural properties optical properties.

Ef.ect of.process parameters on th. density and porosity of.laser melted AlSi10Mg/SiC metal matrix composite

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f.ontiers of.Mech.nical Engineering 2018年第4期13卷 520-527页

作者： Omotoyosi h. f.MODIMU Mark STANf.RD Ch.ke f. ODUOZA Lijuan Zh.NG f.culty of.Science and Engineering School of Engineering Telford Campus University of Wolverhampton WV1 1LY Wolverhampton UK

Laser melting of.aluminium alloy-AlSi10Mg h.s increasingly been used to create specialised products in various industrial applications, h.wever, research.on utilising laser melting of.aluminium matrix composites in replacing specialised parts h.ve been slow on th. uptake. Th.s h.s been attributed to th. complexity of.th. laser melting process, metal/ceramic f.edstock f.r th. process and th. reaction of.th. f.edstock material to th. laser. Th.s, an understanding of.th. process, material microstructure and mech.nical properties is important f.r its adoption as a manuf.cturing route of.aluminium metal matrix composites. Th. ef.ects of.several parameters of.th. laser melting process on th. mech.nical blended composite were th.s investigated in th.s research. Th.s included single track f.rmations of.th. matrix alloy and th. composite alloyed with.5% and 10% respectively f.r th.ir reaction to laser melting and th. f.brication of.density blocks to investigate th. relative density and porosity over dif.erent scan speeds. Th. results f.om th.se experiments were utilised in determining a process window in f.bricating near-f.lly dense parts.

关键词： selective laser melting additive manuf.cturing mech.nical alloying powder metallurgy aluminium metal matrix composite

Controlled cationic ring-opening polymerization of.L-lactide by organic ion pair: novel approach.to isotactic-rich.and crystalline polylactide

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Science Ch.na Ch.mistry 2025年第1期 394-402页

作者： Zh.qiang Ding Mingqian wang Zijing Zh.u Bin wang Yuesh.ng Li Tianjin Key Laboratory of.Composite & f.nctional Materials School of Materials Science and Engineering Tianjin University

Living/controlled cationic ring-opening polymerization （ROP） of.L-lactide is a promising approach.to isotactic-rich.and crystalline poly（L-lactide）.In contrast with.th. unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and th. state of.th. art in th.s f.eld is th. cationic ROP of.L-LA catalyzed by Br?nsted acid/alcoh.l system via activated monomer ***,we reported th. f.rst example of.controlled cationic ROP of.L-LA by using Meerweintype ion pair[Me3O]+[B（C6f.）4]-as th. catalyst.[Me3O]+[B（C6f.）4]-promoted rapid L-LA cationic polymerization in th. absence of.alcoh.l,producing isotactic-rich.and crystalline PLLA with.ut transesterif.cation and epimerization side *** activated ch.in end mech.nism,involving twice SN2 substitution and conf.guration-inversion （S→R→S） with.th. assistance of.released Me2O,was proposed and f.rth.r verif.ed by density f.nctional th.ory and control *** work expands th. catalytic toolbox of.isotactic-rich.and crystalline polylactide *** represents a unique example of.cationic-controlled polymerization of.L-LA catalyzed by an organic ion pair.

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Diameter-dependent in vitro perf.rmance of.biodegradable pure zinc wires f.r suture application

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Journal of.Materials Science & Tech.ology 2019年第8期35卷 1662-1670页

作者： h. Guo R.h. Cao Y.f. Zh.ng J. Bai f. Xue C.L. Ch. State Key Laboratory f.r Turbulence and Complex System and Department of.Materials Science and Engineering College of Engineering Peking University Beijing 100871 China Sch.ol of.Materials Science and Engineering Southeast University Nanjing 211189 China Key Laboratory f.r Advanced Metallic Materials Southeast University Nanjing 211189 China

In th.s study, biodegradable pure zinc wires with.3.0 mm and 0.3 mm in diameter were prepared via h.t-extrusion and subsequent cold-drawing process respectively. Th. microstructure, mech.nical perf.rmance, corrosion beh.vior, in vitro cytocompatibility and antibacterial ef.ect were comparatively *** cold-drawing, th. mech.nical property, especially th. elongation of.th. ф0.3 mm pure Zn wire was improved signif.cantly compared with.th. ф3.0 mm pure Zn wire. Th. in vitro corrosion study including immersion and electroch.mical test sh.wed acceptable corrosion resistance of.th.se two materials in h.nk's solution. Th. in vitro h.man Umbilical Vein Endoth.lial Cells(h.VECs) viability assay sh.wed obviously dif.erent results, in wh.ch.th. ф0.3 mm pure Zn wire demonstrated f.vorable cytocompatibility, wh.le th. ф3.0 mm wire exh.bited severe cytotoxic ef.ect with.100% extract concentration. Both.of.th.m exh.bited partly antibacterial ef.ect on S. aureus. Th.se results demonstrated th. f.asibility of.th. prepared 0.3 mm pure Zn wire as th. potential suture material with.good absorbability.

关键词： Pure zinc Wire Biodegradable metal Suture

Quantif.ing th. Microstructures of.Pure Cu Subjected to Dynamic Plastic Def.rmation at Cryogenic Temperature

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Journal of.Materials Science & Tech.ology 2011年第8期27卷 673-679页

作者： f. Yan h. W. Zh.ng N.R. Tao K. Lu Sh.nyang National Laboratory f.r Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

A pure Cu （99.995 wt%） h.s been subjected to dynamic plastic def.rmation at cryogenic temperature to a strain of.2.1. Th.ee types of.microstructures th.t are related to dislocation slip, twinning and sh.ar banding h.ve been quantitatively ch.racterized by transmission electron microscopy （TEM） assisted by convergent beam electron dif.raction （CBED） analysis. Microstructures originated f.om dislocation slip inside or outside th. sh.ar bands are ch.racterized by low angle boundaries （〈15°） th.t are spaced in th. nanometer scale, wh.reas most def.rmation twins are deviated f.om th. perf.ct ∑3 coincidence （60°/〈111〉） up to th. maximum angle of.9°. Th. quantitative structural ch.racteristics are compared with.th.se in conventionally def.rmed Cu at low strain rates, and allowed a quantitative analysis of.th. f.ow stress-structural parameter relationsh.p.

关键词： Quantitative structural ch.racterization Cu Dynamic plastic def.rmation Trans mission electron microscopy Convergent beam electron dif.raction