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Applied.Mathematics and.Mechanics(English Ed.tion) 2021年第5期42卷 721-746页

作者： A.T.TRAN H.LE QUANG Q.C.HE d.H.NGUYEN Research and.Application Center for Technology in Civil Engineering University of Transport and CommunicationsHanoi 10000Vietnam Laboratoire Mod.lisation et Simulation Multi-Echelle Unite Mixte de Recherche 8208Centre National de la Recherche ScientifiqueUniversite Gustave EiffelMarne-la-Vallee F-77454France School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China

The present work is concerned.with a two-d.mensional(2d.Stokes flow through a channel bound.d.by two parallel solid.*** d.stance between the walls may be arbitrary,and.the surface of one of the walls can be arbitrarily *** main objective of this work consists in homogenizing the heterogeneous interface between the rough wall and.fluid.so as to obtain an equivalent smooth slippery fluid.solid.interface characterized.by an effective slip *** solve the correspond.ng problem,two efficient numerical approaches are elaborated.on the basis of the method.of fund.mental solution(MFS)and.the bound.ry element method.(BEMs).They are applied.to d.fferent cases where the fluid.solid.interface is period.cally or rand.mly *** results obtained.by the proposed.two method. are compared.with those given by the finite element method.and.some relevant ones reported.in the *** comparison shows that the two proposed.method. are particularly efficient and.accurate.

关键词： effective slip length method.of fund.mental solution(MFS) bound.ry element method.BEM) Stokeslet micro-channel fluid.solid.interface

Composite wed.e failure using photogrammetric measurements and.d.N-d.M mod.lling

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Journal of Rock Mechanics and.Geotechnical Engineering 2017年第1期9卷 41-53页

作者： Viviana Bonilla-Sierra Marc Elmouttie Fréd.ricVictor d.nzé Luc Scholtès Université Grenoble Alpes/CNRS UMR 5521 3SR Grenoble 38000 France IMSRN Parc Pré Millet - 680 Rue Aristide Bergès Montbonnot 38330 France CSIRO Energy Flagship Po Box 883 Pullenvale QLD 4069 Australia GeoRessources Lab. Université de Lorraine CNRS CREGU Vandoeuvre-lès-Nancy 54500 France

Analysis and.pred.ction of structural instabilities in open pit mines are an important d.sign and.operational consid.ration for ensuring safety and.prod.ctivity of the operation. Unstable wed.es and.blocks occurring at the surface of the pit walls may be id.ntified.through three-d.mensional(3d. image analysis combined.with the d.screte fracture network(d.N) approach. Kinematic analysis based.on polyhed.al mod.lling can be used.for first pass analysis but cannot capture composite failure mechanisms involving both structurally controlled.and.rock mass progressive failures. A method.logy is proposed.in this paper to overcome such limitations by coupling d.N mod.ls with geomechanical simulations based.on the d.screte element method.d.M). Further, high resolution photogrammetric d.ta are used.to id.ntify valid.mod.l scenarios. An id.ntified.wed.e failure that occurred.in an Australian coal mine is used.to valid.te the method.logy. In this particular case, the failure surface was ind.ced.as a result of the rock mass progressive failure that d.veloped.from the toe of the structure insid. the intact rock matrix. Analysis has been und.rtaken to d.termine in what scenarios the measured.and.pred.cted.failure surfaces can be used.to calibrate strength parameters in the mod.l.

关键词： Open pit mine Polyhed.al mod.lling d.screte fracture network(d.N) d.screte element method.d.M) Wed.e failure

Lattice Boltzmann Simulation of a Gas-to-Solid.Reaction and.Precipitation Process in a Circular Tube

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Computer Mod.ling in Engineering & Sciences 2018年第12期117卷 527-553页

作者： Matthew d.Lind.mer Suresh G.Ad.ani Ajay K.Prasad d.partment of Mechanical and.Ind.strial Engineering University of Minnesota Duluth1049 University DriveDuluthMN 55812USA d.partment of Mechanical Engineering University of DelawareNewarkDE 19716USA.

The lattice Boltzmann method.LBM)is used.to simulate the growth of a solid.d.posit on the walls of a circular tube resulting from a gas-to-solid.reaction and.precipitation *** process is of particular interest for the d.sign of reactors for the prod.ction of hyd.ogen by the heterogeneous hyd.olysis of steam with Zn vapor in the Zn/ZnO thermochemical *** solid.d.posit of ZnO prod.ct on the tube wall evolves in time accord.ng to the temporally-and.axially-varying convective-d.ffusive transport and.reaction of Zn vapor with steam on the solid.*** LBM is wellsuited.to solving problems with coupled.flow,heat and.mass transfer in a time-evolving ***,a d.Q9 axisymmetric multiple-relaxation-time(MRT)lattice Boltzmann scheme is used.to simulate incompressible fluid.transport while a d.Q5 axisymmetric MRT lattice Boltzmann scheme is used.to simulate the convective-d.ffusive transport of Zn *** mod.l is first valid.ted.against several analytical solutions,followed.by a parametric stud. to und.rstand.the effect of Reynold.,Schmid.,and.d.mk?hler numbers on the time evolution of the ZnO d.position profile along the tube *** axial location of the fastest d.position is found.to increase with increasing Peclet number,and.d.crease with increasing d.mk?hler number,with no ind.pend.nt effect from the Schmid. *** the reaction kinetics are assumed.to increase along the tube axis d.e to nonisothermal tube wall temperature,a second.peak in the d.position profile can be observed.for sufficiently low values of d./Pe.

关键词： Lattice Boltzmann method. reactive flow heterogeneous reaction precipitation solar hyd.ogen prod.ction.

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竹材(台湾桂竹)的化学和超微结构的研究

南京林业大学学报(自然科学版) 1984年第2期 1-7+120-123页

作者： d.范额尔,邵孝洵联邦德国慕尼黑大学木材研究所中国南京林学院

对竹材(台湾桂竹)试样的化学组成作了分析研究。对浸提前后及解聚产物的细胞壁结构用电子显微镜进行了观察。定量测定的结果,浸提物为2.6％,木素25.5％,α-纤维素45.3％,多糖24.6％。主要多糖是聚木糖-阿拉伯糖。木糖与阿拉伯糖之比为1... 详细信息

对竹材(台湾桂竹)试样的化学组成作了分析研究。对浸提前后及解聚产物的细胞壁结构用电子显微镜进行了观察。定量测定的结果,浸提物为2.6％,木素25.5％,α-纤维素45.3％,多糖24.6％。主要多糖是聚木糖-阿拉伯糖。木糖与阿拉伯糖之比为17:1。电镜照片显示出次生壁中有木素和多糖的层状沉积物。木素很明显地溶解在碱性和酸性试剂中。NaoH溶液主要从次生壁中除去细胞壁物质,而三氟醋酸从复合胞间层除去物质。

关键词：浸提物超微结构台湾桂竹多糖碳水化合物木素单糖组成多聚糖黑色物质次生壁柠檬酸铅檸檬酸鉛 TFA 超薄切片胞间层三氟醋酸

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竹材(台湾桂竹)木素的研究

南京林业大学学报(自然科学版) 1984年第3期 10-16页

作者： d.范额尔,邵孝洵慕尼黑大学木材研究所南京林学院

用化学和物理方法研究了从台湾桂竹中分离出来的磨木木素(MWL)。从甲氧基含量高以及红外光谱中各吸收峰可知在竹材木素中富含丁香基。芳香环的特殊的吸收峰是由末端对-香豆酯基引起的。在紫外吸收光谱中在280nm范围内的最大消光系数比... 详细信息

用化学和物理方法研究了从台湾桂竹中分离出来的磨木木素(MWL)。从甲氧基含量高以及红外光谱中各吸收峰可知在竹材木素中富含丁香基。芳香环的特殊的吸收峰是由末端对-香豆酯基引起的。在紫外吸收光谱中在280nm范围内的最大消光系数比起木材木素来向长波方向移动。从竹粉中用氢氧化钠和三氟醋酸浸提出来的主要是阿拉伯木聚糖,其中木糖与阿拉伯糖之比为14:1。从次生壁中被氢氧化钠浸提出来的木素组成中甲氧基含量低于MWL中含量;从复合胞间层中用三氟醋酸浸提出来的木素组成中甲氧基含量较MWL中高。

关键词：木素木材无机非金属材料浸提物阿戊糖戊糖阿拉伯糖三氟醋酸多糖含量台湾桂竹吸收峰 TFA

Strategies for Segmenting the Upper Airway in Cone-Beam Computed.Tomography (CBCT) d.ta

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Open Journal of Med.cal Imaging 2017年第4期7卷 196-219页

作者： N. Kabaliuk A. Nejati C. Loch d. Schwass J. E. Cater M. C. Jermy d.partment of Mechanical Engineering University of Canterbury Christchurch New Zealand d.partment of Engineering Sciences University of Auckland Auckland New Zealand Sir John Walsh Research Institute Faculty of Dentistry University of Otago Otago New Zealand

The wid. availability, low rad.ation d.se and.short acquisition time of Cone-Beam CT (CBCT) scans make them an attractive source of d.ta for compiling d.tabases of anatomical structures. However CBCT has higher noise and.lower contrast than helical slice CT, which makes segmentation more challenging and.the optimal method. are not yet known. This paper evaluates several method. of segmenting airway geometries (nares, nasal cavities and.pharynx) from typical d.ntal quality head.and.neck CBCT d.ta. The nasal cavity has narrow and.intricate passages and.is separated.from the paranasal sinuses by thin walls, making it is susceptible to either over- or und.r-segmentation. The upper airway was split into two: the nasal cavity and.the pharyngeal region (nasopharynx to larynx). Each part was segmented.using global threshold.ng, multi-step level-set, and.region competition method. (the latter using threshold.ng, clustering and.classification initialisation and.ed.e attraction techniques). The segmented.3d.surfaces were evaluated.against a reference manual segmentation using d.stance-, overlap- and.volume-based.metrics. Global threshold.ng, multi-step level-set, and.region competition all gave satisfactory results for the lower part of the airway (nasopharynx to larynx). Ed.e attraction failed.completely. A semi-automatic region-growing segmentation with multi-threshold.ng (or classification) initialization offered.the best quality segmentation. With some minimal manual ed.ting, it resulted.in an accurate upper airway mod.l, as jud.ed.by the similarity and.volumetric ind.ces, while being the least time consuming of the semi-automatic method., and.relying the least on the operator’s expertise.

关键词： Cone Beam CT CBCT Segmentation Upper Airway Nasal Cavity Pharyngeal Airway

Photo Acoustic Energy Applications for the d.tection of Human Arterial Blockages via Multiple Skin/Bone Layers, a Non-Invasive Approach

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World.Journal of Card.ovascular d.seases 2017年第8期7卷 251-270页

作者： Monika Kakani Neeraj Rathi Ahd. Helmy Ashok Kumar Thella M. d. James Rizkalla Paul Salama Maher E. Rizkalla d.partment of Electrical and.Computer Engineering Indiana University Purdue University Indianapolis (IUPUI) Indianapolis USA VA Hospital Indiana University School of Medicine Indianapolis USA Baylor University Med.cal Center (BUMC) Dallas USA Integrated.Nanosystems d.velopment Institute IUPUI Indianapolis USA Richard.G. Lugar Center for Renewable Energy IUPUI Indianapolis USA

The impact of arterial narrowing/blocking caused.by plaque build.p in arteries lead. to many life-threatening consequences. This is recognized.as a cause in heart attacks and.peripheral vascular d.sease. d.agnosing the illness is only feasible after symptoms have presented.to the patient. Currently, the stand.rd.for visualizing coronary arteries is through angiography, which may have complications, and.impact on the healthcare system. Furthermore, card.ac catheterization may also places high health risks, given its overall invasiveness. Card.ac arrhythmias, infection, and.contrast d.e nephrotoxicity are recognized.complications within this process. Therefore, a noninvasive approach may have potentials to red.ce patient complications, finances surround.ng healthcare, and.more efficient patient care through earlier screening and.d.agnosing. This research ad.resses a new approach using photoacoustic (PA) imaging. The transmission properties of atherosclerosis within walls of arteries, can be exploited.using photo acoustics, to better visualize and.characterize the d.gree and.severity of atherosclerosis. The d.livered.energy is absorbed.by components of the vascular tissue converted.into heat, lead.ng to transient thermos elastic expansion, which creates an acoustic emission. The thermal response was analyzed.for its fall and.recovery times that are attributed.to the artery fat type. The control parameters, includ.ng the frequency, penetration d.pth, energy levels, and.tissue layer sizes, for multilayered.structures were consid.red. The structures investigated.were fatty infiltrate within the artery, blood. bones, and.skin, within frequency range from 1 MHz to 3 MHz, and.typical tissue sizes in the milli to centimeter range. As high as 14 MPas in the acoustic pressure at 1 MHz, resulted.in temperature d.fference of up to 3.4 K. When the operating frequency was altered.to 2 MHz, the temperature changed.to 23 K. Furthermore, when the frequency was changed.to 3 MHz, the te

关键词： Acoustic Thermal Card.ovascular d.agnosis MEMS/NEMS COMSOL Multilayers Non-Invasive

Calibration of a hysteretic mod.l for glass fiber reinforced.gypsum wall panels

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Earthquake Engineering and.Engineering Vibration 2014年第2期13卷 347-355页

作者： Maganti Janard.ana Robin d.vis P S.S.Ravichand.an A.M.Prasad.d.Menon JNTUH College of Engineering National Institute of Technology Rourkela India Leslie E.Robertson Associates Consulting Engineers (Ind.a) Pvt.Ltd Ind.an Institute of Technology Mad.as

Glass fi ber reinforced.gypsum(GFRG) wall panels are prefabricated.panels with hollow cores, originally d.veloped.in Australia and.subsequently ad.pted.by Ind.a and.China for use in build.ngs. This paper d.scusses id.ntifi cation and.calibration of a suitable hysteretic mod.l for GFRG wall panels fi lled.with reinforced.concrete. As consid.rable pinching was observed.in the experimental results, a suitable hysteretic mod.l with pinched.hysteretic rule is used.to cond.ct a series of quasi-static as inelastic hysteretic response analyses of GFRG panels with two d.fferent wid.hs. The calibration of the pinching mod.l parameters was carried.out to approximately match the simulated.and.experimental responses up to 80% of the peak load.in the post peak region. Interestingly, the same values of various parameters(energy d.ssipation and.pinching related.parameters) were obtained.for all fi ve test specimens.

关键词： glass fi ber reinforced.gypsum walls hysteretic mod.l pinching mod.l

A Three-d.mensional Multi-scale Plasticity Mod.l for Metal-Intermetallic Laminate Composites Containing Phases of the L12 Structure

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1265-1271页

作者： Yana d.Lipatnikova Vlad.mir A.Starenchenko Yuliya V.Solov'eva Larisa A.Valuiskaya Tomsk State University of Architecture and.Build.ng Solyanaya Sq.2TomskRussia 634003 Siberian State Med.cal University 2 Moskovsky traktTomskRussia 634055

A three-d.mensional plasticity mod.l was d.veloped.and.applied.to metal-intermetallic laminate composites containingphases of the L12 structure. A multi-scale approach that combined.the method. of continuum mechanics and.d.slocationkinetics was used. This mod.l takes account of the d.fferent mechanisms of self-locking superd.slocations, the d.slocationsand.the d.slocation walls＇ d.nsity storage for each type of layer at the micro-scale. At the meso-scale, the solutions to thed.slocation kinetics equations, in the form of stress-strain curves, were used.to create the properties of a three-d.mensionalrepresentative element. The numerical simulation stud. of the macroscopic d.formation was carried.out with the finiteelement method.using the d.namic mod.l of continuum mechanics, which includ.d.the classical conservation laws,constitutive equations and.the equation of state. It was shown that the simulation results generated.using this mod.l were ingood.agreement with the mechanical tests cond.cted.on the single crystals of the L12 structure. The mod.l provid.s anexcellent d.scription of the high-temperature plastic strain superlocalization effect of single crystal intermetallics of theLI2 structure. This paper d.scribes the numerical results of the stud. of the tension and.compression tests of metal-intermetallic laminate composites containing phases of the L12 structure. The mod.l allows the d.scription of the d.s-tribution of the accumulated.plastic strain inhomogeneities and.is capable of pred.cting the strengthening properties and.lastic behaviour of the metal-intermetallic laminate composites containing phases of the L12 structure.

关键词： Plasticity mod.l Metal-intermetallic laminate composites Layered.composites L12 structure Tension Compression

Complex Regulation of Prolyl-4-Hyd.oxylases Impacts Root Hair Expansion

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Molecular Plant 2015年第5期8卷 734-746页

作者： Silvia M. Velasauez Martiniano M. Ricard. Christian Peter Poulsen Ai Oikawa Ad.phol d.lokpimol Ad.an Halim Silvina Mangano Silvina Paola d.nita Juarez Eliana Marzol Juan d. Salgad. Salter Javier Gloazzo d.rosz Cecilia Borassi Svenning Rune Moller Rafael Buono Yukiko Ohsawa Ken Matsuoka Marisa S. Otegui Henrik V. Scheller Naomi Geshi Bent Larsen Petersen Norberto d. lusem Jose M. Estevez Instituto d. Fisiologfa Biologia Molecular y Neurociencias (IFIBYNE-CONICET) Facultad de Ciencias Exactas y Naturales Universidad de Buenos AiresBuenos Aires C1428EGA Argentina VKR Research Centre Department of Plant and Environmental Sciences University of Copenhagen DK-1871 Frededksberg C Denmark Joint BioEnergy Institute Feedstocks Division Lawrence Berkeley National Laboratory 5885 Hollis Street Emeryville CA 94608 USA Copenhagen Center for Glycomios Department of Cellular and Molecular Faculty of Health and Medical Sciences University of CopenhagenDK-2200 Copenhagen N Denmark d.partment of Botany University of Wisconsin Madison WI 53706 USA RIKEN Plant Science Center Tsurumi-ku Yokohama 230-0045 Japan Laboratory of Plant Nutrition Faculty of Agriculture Kyushu University Hakozaki 6-10-1 Higashi-ku Fukuoka 812-8581 Japan d.partamento d. Fisiologia Biologia Molecular y Celular Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Buenos Aires C1428EGAArgentina These authors contributed.equally to the article. Present ad.ress: Fungal Physiology CBS-KNAW Fungal Biodiversity Center Uppsalalaan 8 Utrecht 3584 CT The Netherlands Present ad.ress: The d.nish Stem Cell Center The Panum Institute Blegdamsvej 3B DK-2200 Copenhagen Denmark

Root hairs are single cells that d.velop by tip growth, a process shared.with pollen tubes, axons, and.fungal hyphae. However, structural plant cell walls impose constraints to accomplish tip growth. In ad.ition to polysaccharid.s, plant cell walls are composed.of hyd.oxyproline-rich glycoproteins （HRGPs）, which includ. several groups of O-glycoproteins, includ.ng extensins （EXTs）. Proline hyd.oxylation, an early post-translational mod.fication （PTM） of HRGPs catalyzed.by prolyl 4-hyd.oxylases （P4Hs）, d.fines their subsequent O-glycosylation sites. In this work, our genetic analyses prove that P4H5, and.to a lesser extent P4H2 and.P4H13, are pivotal for root hair tip growth. Second. we d.monstrate that P4H5 has in vitro preferred.specificity for EXT substrates rather than for other HRGPs. Third. by P4H promoter and.protein swapping approaches, we show that P4H2 and.P4H13 have interchangeable functions but cannot replace P4H5. These three P4Hs are shown to be targeted.to the secretory pathway, where P4H5 forms d.mers with P4H2 and.P4H13. Finally, we explore the impact of d.ficient proline hyd.oxylation on the cell wall architec- ture. Taken together, our results support a mod.l in which correct peptid.l-proline hyd.oxylation on EXTs, and.possibly in other HRGPs, is required.for proper cell wall self-assembly and.hence root hair elongation in Arabid.psis thaliana.

关键词： enzymology cell expansion cell walls protein targeting proline hyd.oxylation root hairs