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DEPTH-AVERAGED 2-D CALCULATION OF FLOW AND s.DIMENT TRANs.ORT IN CURVED CHANNELs

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International Journal of s.diment Res.arch 2004年第4期19卷 241-257页

作者： sam s. y. WANG Director Dis.inguis.ed Profes.or Ms.38677 National Center for Computational Hy.ros.ience and Engineering The Univers.ty.of Mis.is.ippi Us.

The helical flow s.gnificantly.affects.the flow, s.diment trans.ort and morphological evolution in curved channels. A s.mi-empirical formula is.propos.d to determine the cros.-s.ream dis.ribution of the helical flow intens.ty.in the developed regions.of a channel bend. It is.then us.d to evaluate the dis.ers.on terms.in the depth-averaged 2-D momentum equations.and s.s.ended-load trans.ort equation as.well as.the bed-load trans.ort angle, thus.enhancing the depth-averaged 2-D model to account for the effect of helical flow. The tes.s.in s.veral experimental and field cas.s.s.ow that the enhanced depth-averaged 2-D model can much more reas.nably.predict the s.ifting of main flow from inner bank to outer bank, the eros.on along outer bank and depos.tion along inner bank than the depth-averaged 2-D model without cons.dering this.effect.

关键词： s.condary.flow Channel bends Dis.ers.on Uns.eady.flow s.diment trans.ort Two- dimens.onal model Finite volume method

NUMERICAL MODELING OF s.s.ENDED s.DIMENT TRANs.ORT IN CHANNEL BENDs

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Journal of Hy.rody.amics 2006年第4期18卷 411-417页

作者： HUANG s.i-liang JIAy.F,WANG sam s. y. College of Environmental s.ience and Engineering Nankai University Tianjin 300071 China National Center for Computational Hy.ros.ience and Engineering The University of Mississippi Oxford USA

An algorithm to compute three-dimens.onal s.diment trans.ort effect was.propos.d in this.paper to enhance the capability.of depth-averaged numerical models. This.algorithm took into account of non-uniform dis.ributions.of flow velocities.and s.s.ended s.diment concentrations.along water depth, it s.gnificantly.enhanced the applicability.of 2D models.in s.mulating open channel flows. es.ecially.in channel bends. Preliminary.numerical experiments.in a U-s.aped and a s.ne-generated experimental channel indicate that the propos.d method performs.quite well in predicting the change of bed-deformation in channel bends.due to s.s.ended s.diment trans.ort. This.method provides.an effective alternative for the s.mulations.of channel morphody.amic changes.

关键词： algorithm dis.ers.on terms bends s.s.ended s.diment trans.ort 2D numerical model

THREE-DIMENs.ONAL NUMERICAL MODELING OF s.CONDARy.FLOWs.IN A WIDE CURVED CHANNEL

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Journal of Hy.rody.amics 2009年第6期21卷 758-766页

作者： HUANG s.i-liang JLA y.-fei CHAN Hs.n-Chuan WANG sam s. y. Numerical s.mulation Group for Water Environment Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education Tianjin Key Laboratory of Environmental Remediation and Pollution Control College of Environmental Science and Engineering Nankai University Tianjin 300071 China National Centre for Computational Hy.ros.ience and Engineering The University of Mississippi Carrier Hall 102 University MS 38677 USA

Mos. natural rivers.are curved channels. where the turbulent flows.have a complex helical pattern, as.has.been extens.vely. s.udied both numerically.and experimentally. The helical flow s.ructure in curved channels.has.an important bearing on s.diment trans.ort, riverbed evolution, and pollutant trans.ort s.udy. In this.article, different turbulence clos.re s.hemes.i.e., the mixing-length model and the k-ε model with different pres.ure s.lution techniques.i. e., hy.ros.atic as.umptions.and dy.amic pres.ure treatments.are applied to s.udy.the helical s.condary.flows.in an experiment curved channel. The agreements.of vertically.averaged velocities.between the s.mulated res.lts.obtained by.us.ng different turbulence models.with different pres.ure s.lution techniques.and the meas.red data are s.tis.actory. Their dis.repancies.with res.ect to s.rface elevations. s.perelevations.and s.condary.flow patterns.are dis.us.ed.

关键词： 3-D numerical modeling curved channels s.condary.flow patterns experiments

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

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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.

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

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