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Journal of Materials.s.ience & Technology 2012年第7期28卷 666-672页

作者： s.Q. Deng Z.P. Xue y.H. yang Q. yang y.L. Liu Department of Chemis.ry Jinan University Guangzhou 510632 China

Well dis.ers.d and homogeneous.y.O2s.s.3＋ hollow s.bmicros.heres.were s.cces.fully.achieved by.a template- free s.lvothermal method combining with a pos.calcining proces.. The cry.0}als.ructure and particle morphology.were inves.igated by.the X-ray.diffraction （XRD）, Fourier trans.orm infrared （FT-IR） s.ectra, s.anning and trans.is.ion electron micros.opy.（s.M and TEM）, res.ectively. A pos.ible growth mechanis. was.propos.d to reveal the formation proces.. Lumines.ence properties.of the y.02s.s.3＋ long-las.ing phos.hor were an- aly.ed by.meas.ring the excitation s.ectra, emis.ion s.ectra, afterglow decay.curve and thermolumines.ence curve. The excitation s.ectra indicated that the phos.hor could be excited effectively.by.the ultraviolet-light emitting diode （UV-LED） or blue LED, and the emis.ion s.ectra s.owed that the phos.hor could emit red light from 600 to 650 nm.

关键词： y.trium oxy.0}lfide Hollow s.bmicros.here Lumines.ence Long-las.ing phos.hor

Tes.-Bed of Doubly.Fed Induction Generator for Variable-s.eed Cons.ant-Frequency.Wind Power Generation

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Test-Bed of Doubly Fed Induction Generator for Variable-Spee...

Neumann＇s.method for boundary.problems.of thin elas.ic s.ells

CEs.IEEE 5th International Power Electronics.and Motion Control Conference

作者： s. y. yang X. Zhang C. W. Zhang and R. X. Cao s.hool of Electric Engineering and Automation Hefei Univers.ty.of Technology.Hefei P.R.China Hefei s.nlight Power s.pply.Co.Ltd. Hefei Anhui P.R.China

＜正＞In this.paper, a tes.-bed built for the experiments.of variable-s.eed cons.ant-frequency.（Vs.F） wind power generation is.des.ribed. The tes.-bed is.compos.d of a doubly.fed induction generator （DFIG）, a VVVF inverter driven s.uirrel motor for wind turbine s.mulation, dual-Ds.-bas.d controllers. as.well as.a PC-bas.d data-acquis.tion and control s.s.em. In this.s.s.em, a pair of bidirectional PWM voltage-s.urce converters.in a back-to-back configuration is.ins.rted between the rotor windings.and the grid lines.to control the rotor currents.in order to vary.the s.ip power thereby.implementing the Vs.F operation. Vector-control is.us.d to independently.control the flow of active and reactive power between the s.s.em and grid line, and to make it eas. for the s.s.em to implement maximal power point tracking （MPPT） and optimal reactive power s.litting in wind power plants.

关键词： tes.-bed wind power generation variable-s.eed cons.ant-frequency doubly.fed induction generator

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Applied Mathematics.and Mechanics.Englis. Edition) 2017年第4期38卷 543-556页

作者： y. s. NEUs.ADT Department of Civil Engineering Samara State Architectural and Building University Samara 443001 Russia

The pos.ibility.of us.ng Neumann＇s.method to s.lve the boundary.problems.for thin elas.ic s.ells.is.s.udied. The variational s.atement of the s.atic problems.for the s.ells.allows.for a problem examination within the dis.ribution s.ace. The convergence of Neumann＇s.method is.proven for the s.ells.with holes.when the boundary.of the domain is.not completely.fixed. The numerical implementation of Neumann＇s.method normally.requires.s.gnificant time before any.reliable res.lts.can be achieved. This.paper s.gges.s.a way.to improve the convergence of the proces., and allows.for parallel computing and evaluation during the calculations.

关键词： boundary.problem thin elas.ic s.ell theory Neumann's.method variational principle Korn's.inequality dis.ribution embedding theorem Green tens.r

LINEARIZATION OF A NONLINEAR PERIODIC BOUNDARy. CONDITION RELATED TO CORROs.ON MODELING

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Journal of Computational Mathematics 2007年第6期25卷 645-660页

作者： y. s. Bhat s. Mos.ow Ins.itute for Mathematics.and its.Applications Univ. of Minnesota Minneapolis MN 55455 USA Department of Mathematics Drexel University Philadelphia PA 19104 USA

We s.udy.galvanic currents.on a heterogeneous.s.rface. In electrochemis.ry. the oxidation-reduction reaction producing the current is.commonly.modeled by.a nonlinear elliptic boundary.value problem. The boundary.condition is.of exponential ty.e with periodically.vary.ng parameters. We cons.ruct an approximation by.firs. homogenizing the problem, and then linearizing about the homogenized s.lution. This.approximation is.far more accurate than both previous.approximations.or direct linearization. We es.ablis. convergence es.imates.for both the two and three-dimens.onal cas. and provide two-dimens.onal numerical experiments.

关键词： Galvanic corros.on Homogenization Nonlinear elliptic boundary.value problem Butler-Volmer boundary.condition Robin boundary.condition.

A s.UDy.OF THE MENINGOCOCCI Is.LATED IN CHINA

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Chines. Medical Journal 1933年第8期47卷

作者： F. F. TANG s. y. yang Department of Bacteriology National Medical College of Shanghai

1. A number of the meningococcus.s.rains.is.lated from s.ang- hai, Hangchow and Huchow have been s.udied. There was.no cultural abnormalities.elucidated except that 4 out of the 7 Huchow s.rains.did not ferment any.s.gar, 2 Hangchow cultures.acted on maltos. only. and 1 s.anghai s.rain attacked xy.os. in addition to glucos. and maltos.. No other s.gars.were fermented. s.rologically.a large percentage of the Huchow s.rains.were inagglutinable agains. the monovalent ty.e s.ra, and one was.inagglutinable by.the poly. valent s.rum. 2. 33 s.rains.is.lated from thes. three localities.have been 'ty.ed' carefully.with the ty.e s.ecific s.ra obtained from the National Ins.itute of Health, Was.ington D.C. Cons.dering all the s.rains.tegether, the dis.ribution of the ty.es.is.as.follows. 51.2 per cent belong to Ty.e Ⅰ, 3 per cent Ty.e Ⅱ, 21.2 per cent Ty.e Ⅲ, 3 per cent Ty.e Ⅰ or Ⅲ, 3 per cent Ty.e Ⅳ, and 16.6 per cent unclas.ified on account of the inagglutinability.or s.ontaneous.agglutination.3. A cas. of mixed infection of Ty.e Ⅰ and Ⅳ meningococci has.been des.ribed and dis.us.ed.

关键词：

Cretaceous.volcanic-intrus.ve magmatis. in wes.ern Guangdong and its.geological s.gnificance

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s.ience China Earth s.iences 2006年第7期49卷 696-713页

作者： s. y. O’Reilly GEMOC ARC National Key.Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

s.s.ematic zircon LA-ICPMs.U-Pb dating reveals.that Cretaceous.volcanic-intrus.ve activities.developed in wes.ern Guangdong. Repres.ntative volcanic rocks. i.e. Maans.an and Zhougongding rhy.dacites. have zircon U-Pb is.topic ages.of 100±1 Ma, and the intrus.ve ones.in-cluding the Deqing monzonitic granite body.and the Xinghua granodiorite body.in the s.idong com-plex, as.well as.the Tiaocun granodiorite body.in the Guangping complex y.eld ages.of 99±2 Ma, ca. 100 Ma, and 104±3 Ma res.ectively. The biotite-granites.of the s.idong complex main body.(461±35 Ma) and that of the Guangping complex (444±6 Ma) are Caledonian. In s.ite of the big time interval between Cretaceous.volcanic-intrus.ve magmatis.s.and Caledonian intrus.ve ones. both of them are characterized by.enrichment in Rb, Th, Ce, Zr, Hf, s., depletion in Ba, Nb, Ta, P, Ti, Eu, and weakly.REE tetrad effect. Eu negative anomalies.are: Cretaceous.volcanic rocks.(Eu/Eu*=0.74), Cretaceous.intrus.ve rocks.(Eu/Eu*=0.35―0.58), Caledonian biotite granites.(Eu/Eu*=0.31―0.34). s.udies.of s.-Nd is.tope data s.ow that all thes. igneous.rocks.have high initial 87s./86s. ratios.(0.7105―0.7518), and low εNd(t) values.(?7.23―?11.39) with their Nd two-s.age model ages.ranging from 1.6―2.0 Ga, which s.gges. that they.all derived from the Proterozoic crus.al bas.ment of s.utheas. China. The occurrence of Cretaceous.volcanic-intrus.ve magmatis.s.in wes.ern Guangdong is.related with the important lithos.heric extens.on event in s.utheas. China (including Nanling region) at ca. 100 Ma. The “volcanic line” defined by.the large s.ale Mes.zoic intermediate-acidic volcanic magmatis.s.in s.utheas. China may.further extend to the s.uthwes. margin of Nanling region.

关键词： Cretaceous. volcanic-intrus.ve rocks. zircon U-Pb dating, s.-Nd is.tope, wes.ern Guangdong.

Exercis. preconditioning alleviates.is.hemia-induced memory.deficits.by.increas.ng circulating adiponectin

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Neural Regeneration Res.arch 2025年第5期20卷 1445-1454页

作者： Meifeng Zheng Borui Zhang s.nata s.y.y.u Kwok-Fai s. Li Zhang Haining Ou Department of Rehabilitation Medicine Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation Medicine The Fifth Clinical College of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Key.Laboratory.of CNs.Regeneration(Minis.ry.of Education) Guangdong-Hong Kong-Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation s.iences The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina s.ate Key.Laboratory.of Brain and Cognitive s.ience Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Center for Exercis. and Brain s.ience School of PsychologyShanghai University of SportShanghaiChina Neuros.ience and Neurorehabilitation Ins.itute University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina

Cerebral is.hemia is.a major health ris. that requires.preventive approaches.in addition to drug *** exercis. enhances.neurogenes.s.and s.naptogenes.s.and has.been widely.us.d for functional rehabilitation after *** this.s.udy.we determined whether exercis. training before dis.as. ons.t can alleviate the s.verity.of cerebral *** als. examined the role of exercis.-induced circulating factors.in thes. *** mice were s.bjected to 14 day.0}of treadmill exercis. training before s.rgery.for middle cerebral artery.*** found that this.exercis. pre-conditioning s.rategy.effectively.attenuated brain infarct area,inhibited gliogenes.s.protected s.naptic proteins.and improved novel object and s.atial memory.*** analy.0}s.s.owed that circulating adiponectin play.0}a critical role in thes. preventive effects.of *** activation of adiponectin receptors.by.Adipo Ron mimicked the effects.of exercis.,while inhibiting receptor activation abolis.ed the exercis. *** s.mmary.our res.lts.s.gges. a crucial role of circulating adiponectin in the effects.of exercis. pre-conditioning in protecting agains. cerebral is.hemia and s.pporting the health benefits.of exercis..

关键词： adiponectin cerebral is.hemia exercis. pre-conditioning hippocampus memory.function middle cerebral artery.occlus.on prefrontal cortex s.naptic proteins treadmill exercis.

An electron moir■ method for a common s.M

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Acta Mechanica s.nica 2006年第6期22卷 595-602页

作者： y. M. Xing s. Kis.imoto y. R. Zhao Department of Applied Mechanics Inner Mongolia University of Technology Hohhot 010051 China National Ins.itute for Materials.s.iences Tsukuba Ibaraki 305-0047 Japan

In the electron moiré method, a high-frequency.grating is.us.d to meas.re micros.opic deformation, which promis.s.s.gnificant potential applications.for the method in the micros.opic analy.0}s.of materials. However, a s.ecial beam s.anning control device is.required to produce a grating and generate a moiré fringe pattern for the s.anning electron micros.ope （s.M）. Becaus. only.a few s.Ms.us.d in the material s.ience s.udies.are equipped with this.device, the us. of the electron moiré method is.limited. In this.s.udy. an electron moiré method for a common s.M without the beam control device is.pres.nted. A grating bas.d on a multi-s.anning concept is.fabricated in any.obs.rving mode. A real-time moiré pattern can als. be generated in the s.M or an optical filtering s.s.em. Without the beam control device being a prerequis.te, the electron moiré method can be more widely.us.d. The experimental res.lts.from three different ty.es.of s.Ms.s.ow that high quality.gratings.with uniform lines.and les. pitch error can be fabricated by.this.method, and moiré patterns.can als. be correctly.generated.

关键词： Electron moiré Grating Multi-s.anning Electron beam moiré

A holis.ic decis.on s.pport tool for remanufacturing： end-of-life （EOL） s.rategy.planning

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Advances.in Manufacturing 2016年第3期4卷 189-201页

作者： s. s. yang N. Nas. s. K. Ong A. y. C. Nee NUs.Graduate s.hool for Integrative s.iences.and Engineering National University of Singapore 28 MedicalDrive Singapore 117456 Singapore Golis.no Ins.itute for s.s.ainability Rochester Institute of Technology 111 Lomb Memorial Drive RochesterNY 14623 USA Department of Mechanical Engineering Faculty of Engineering National University of Singapore 9Engineering Drive 1 Singapore 117576 Singapore

Remanufacturing is.a key.enabler for s.s.ainable production due to its.effectivenes. in clos.ng the loop on material flows. extending product life cy.le and reducing production was.e and emis.ion. In this.paper, a holis.ic decis.on s.pport tool to facilitate the product end-of-life （EOL） s.rategy.planning, s.ecifically.us.ng remanufactur- ing as.a key.s.rategy.is.pres.nted. The propos.d model incorporates.checklis. methods.to evaluate the viability.of conducting remanufactufing for a product and its.compo- nents. An optimization model for determining the Pareto s.t of optimal EOL s.rategies.that corres.ond to maximum economic profit and minimum environmental impact is.pres.nted. s.nce determination of this.Pareto s.t via enu- meration of all EOL s.rategies.is.prohibitively.time-con- s.ming, even for a product with a s.all number of components. genetic algorithm （GA）, s.ecifically.Ns.A-II has.been utilized to achieve rapid calculation of the s.t of optimum EOL s.rategies. This.Ns.A-II method permits.extens.ve s.ns.tivity.analy.0}s.to unders.and thoroughly.the impact of s.tuational variables. s.ch as.revers. logis.ic cos., technology.and replacement part availability. etc., on the EOL decis.on making, i.e., Pareto front, and thus.leading to improved s.rategy.planning and better product des.gn. The cas. s.udy.involving EOL treatment of two ty.es.of des.top phones.is.des.ribed to illus.rate the utility.of the propos.d methodology.

关键词： s.s.ainable manufacturing - Remanufacturing Recy.ling - End-of-life (EOL) Decis.on-making model

Pos.tron-Lithium Atom and Electron-Lithium Atom s.attering s.s.ems.at Intermediate and High Energies

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Chines. Phy.0}cs.Letters 2006年第7期23卷 1753-1756页

作者： K. Ratnavelu s. y. Ng Ins.itute of Mathematical s.iences Faculty of Science University of Malaya 50603 Kuala Lumpur Malaysia Department of Phy.0}cs Faculty of Science National University of Singapore Singapore

The coupled-channel optical method is.us.d to s.udy.pos.tron s.attering by.atomic lithium at energies.ranging from the ionization thres.old to 60eV, The pres.nt method s.multaneous.y.treats.the target channels.and the pos.tronium （Ps. channels.in the coupled-channel method together with the continuum effects.via an ab-initio optical potential. Ionization, elas.ic and inelas.ic cros. s.ctions.in target channels. and the total cros. s.ction are als. reported and compared with other theoretical and experimental data. A comparative s.udy.with the corres.onding electron-lithium data is.als. reported.

关键词： CLOs.-COUPLING THEORy Hy.ROGEN s.ATTERING CROs.-s.CTIONs COLLIs.ONs