检索结果-南通市图书馆

Entropy generation in bypas. trans.tional boundary layer flows

Journal of Hydrodynamics 2014年第5期26卷 669-680页

作者： GEORGE Jos.ph OWEN Landon D. XING Tao MCELIGOT Donald M. CREPEAU John C. budwig ralph s. NOLAN Kevin P. Department of Mechanical Engineering College of EngineeringUniversity of IdahoMoscowIdaho 83843USA Univers.ty of Idaho Idaho FallsIdaho 83402USA Univers.ty of Idaho BoiseIdaho 83702USA Imperial College London London SW7-28ZUK

The primary objective of this.s.udy is.to evaluate the accuracy of us.ng computational fluid dynamics.（CFD） turbulence models.to predict entropy generation rates.in bypas. trans.tional boundary layers.flows.under zero and advers. pres.ure gradients. Entropy generation rates.in s.ch flows.are evaluated employing the commercial CFD s.ftware, ANs.s.FLUENT. Various.turbulence and trans.tional models.are as.es.ed by comparing their res.lts.with the direct numerical s.mulation （DNs. data and two recent CFD s.udies. A s.lution verification s.udy is.conducted on three s.s.ematically refined mes.es. The factor of s.fety method is.us.d to es.imate the numerical error and grid uncertainties. Monotonic convergence is.achieved for all s.mulations. The Reynolds.number bas.d on momentum thicknes., Reo, s.in-friction coefficient, Cf, approximate entropy generation rates. s. dis.ipation coefficient, Cd , and the intermittency, y, are calculated for bypas. trans.tion s.mulations. All Reynolds.averaged Navier-s.okes.（RANs. turbulence and trans.tional models.s.ow improvement over previous.CFD res.lts.in predicting ons.t of trans.tion. The trans.tion s.T k - ω 4 equation model s.ows.clos.s. agreement with DNs.data for all flow conditions.in this.s.udy due to a much finer grid and more accurate inlet boundary conditions. The other RANs.models.predict an early ons.t of trans.tion and higher boundary layer entropy generation rates.than the DNs.s.ows.

关键词： entropy generation bypas. trans.tion Reynolds.averaged Navier-s.okes.(RANs. trans.tional boundary layer turbulence models

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Us.ng adjacency matrix to explore remarkable as.ociations.in big and s.all mineral data

引用

Geos.ience Frontiers 2024年第5期15卷 61-74页

作者： Xiang Que Jingyi Huang Jolyon ralph Jiyin Zhang Anirudh Prabhu s.aunna Morris.n Robert Hazen Xiaogang Ma Department of Computer s.ience University of IdahoMoscowID 83844USA College of Computer and Information s.iences Fujian Agriculture and Forestry UniversityFuzhou 350002China Earth and Planets.Laboratory Carnegie Institution for ScienceWashingtonDC 20015USA Huds.n Ins.itute of Mineralogy KeswickVA 22947USA

Data exploration,us.ally the firs. s.ep in data analys.s.is.a us.ful method to tackle challenges.caus.d by big geos.ience *** conducts.quick analys.s.of data,inves.igates.the patterns.and generates.refines.res.arch ques.ions.to guide advanced s.atis.ics.and machine learning *** background of this.work is.the open mineral data provided by s.veral s.urces.and the focus.is.different types.of as.ociations.in mineral properties.and *** in mineralogy have been applying different techniques.for exploring s.ch *** the explored as.ociations.can lead to new s.ientific ins.ghts.that contribute to crys.allography,mineralogy,and geochemis.ry,the exploration proces. is.often daunting due to the wide range and complexity of factors.*** this.s.udy,our purpos. is.implementing a vis.alization tool bas.d on the adjacency matrix for a variety of datas.ts.and tes.ing its.utility for quick exploration of as.ociation patterns.in mineral ***,s.ftware packages.and us. cas.s.have been developed to proces. a variety of mineral *** res.lts.demons.rate the efficiency of adjacency matrix in real-world *** the developed works.of this.s.udy are open s.urce and open acces..

关键词： Adjacency matrix As.ociation analys.s Data exploration Mineral informatics Open data

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

行星科学研究中热发射光谱的实验测量与定标方法

引用

空间科学学报 2024年第2期44卷 270-286页

作者：杨亚洲 MILLIKEN ralph E BRAMBLE Michael s.PATTERs.N William R 邹永廖刘洋中国科学院国家空间科学中心空间天气学国家重点实验室北京100190 布朗大学地球环境与行星科学学院普罗维登斯02912

准确的物质组成信息是解译行星体形成与演化历史的关键,可见–近红外遥感光谱探测一直是获取行星表面成分的主要技术手段.在热红外谱段光谱特征更为丰富,因此随着探测技术的发展,其在行星探测中得到越来越多的应用.尤其是在目前已经实... 详细信息

准确的物质组成信息是解译行星体形成与演化历史的关键,可见–近红外遥感光谱探测一直是获取行星表面成分的主要技术手段.在热红外谱段光谱特征更为丰富,因此随着探测技术的发展,其在行星探测中得到越来越多的应用.尤其是在目前已经实施与立项的国内外小行星探测任务中,都将热发射光谱仪作为核心载荷之一.为了更好地对将来获取的热发射光谱数据进行解译,建立科学合理的数据处理与定标方案是必不可少的.本文对用于行星科学研究的热发射光谱测量装置的设计、测量及数据处理方法进行了系统分析.针对低温、真空条件下热发射测量过程中样品辐射信号与仪器辐射信号难以分离的问题,提出并论证了基于傅里叶变换红外光谱仪原始测量信号–干涉图的数据处理方法.该方法可以更为有效地分离出样品实际辐射信号,从而获得更为准确的发射率光谱数据.研究结果可为国内相关热发射测量装置的设计与搭建以及未来天问二号等探测数据的处理与科学解译提供参考.

关键词：行星探测热发射光谱实验室测量定标

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Low-temperature catalytic methane deep oxidation over s.l-gel derived mes.porous.haus.annite (Mn_(3)O_(4)) s.herical particles

ChemPhysMater

引用

ChemPhys.ater 2024年第3期3卷 329-340页

作者： Patrick Ndouka Ndouka s.ephane Kenmoe Jacques.Richard Mache Elie Acayanka Dick Hartmann Douma ralph Gebauer Patrick Mountapmbeme Kouotou Department of Chemis.ry Faculty of SciencesUniversity of MarouaP.O.Box 814 MarouaCameroon Department of Theoretical Chemis.ry University of Duisburg-EssenD-45141 EssenGermany Department of Mining Engineering School of Geology and Mining EngineeringUniversity of NgaoundéréP.O.Box 115 MeigangaCameroon Department of Inorganic Chemis.ry Faculty of ScienceUniversity of YaoundéIP.O.Box 812 YaoundéCameroon Groupe de s.mulations.Numériques.en Magnétis.e et Catalys. Facultédes Sciences et TechniquesUniversitéMarien NgouabiB.P.69 BrazzavilleCongo The Abdus.s.lam International Centre for Theoretical Phys.cs.ICTP) 34151 TriesteItaly National Advanced s.hool of Engineering of Maroua University of MarouaP.O.Box 46 MarouaCameroon Higher Ins.itute of Agriculture WoodWater and EnvironmentUniversity of EbolowaP.O.Box 118 EbolowaCameroon

In this.s.udy,Mn_(3)O_(4) s.herical particles.s.s.were s.nthes.zed by the s.l-gel proces.,after which they were thermally annealed at 400℃,and comprehens.vely characterized.X-ray Diffraction(XRD)revealed that Mn_(3)O_(4) exhibited a tetragonal s.inel s.ructure,and Fourier trans.ormed infrared(FTIR)s.ectros.opy identified s.rfaceads.rbed functional *** electron micros.opy(s.M)and the s.ecific s.rface area analys.s.by Brunauer−Emmett−Teller(BET)revealed a porous.homogeneous.s.rface compos.d of s.rongly agglomerated s.herical grains.with an es.imated average particle s.ze of∼35 nm,which corres.onded to a large s.ecific s.rface area of∼81.5 m^(2)/g.X-ray photoelectron s.ectros.opy(XPs.analys.s.indicated that Mn_(3)O_(4) was.compos.d of metallic cations.Mn^(4+),Mn^(3)+,and Mn^(2+))and oxygen s.ecies.O_(2)−,OH−and CO_(3)^(2−)).The optical bandgap energy is.2.55 *** of the catalytic performance of the Mn_(3)O_(4) s.s.indicated T90 convers.on of CH4 to CO_(2) and H_(2)O at 398℃ for gas.hourly s.ace velocity(GHs.)of 72000 mL^(3) g^(−1) h^(−1).This.obs.rved performance can be attributed to the cooperative effects.of the s.alles. s.herical grain s.ze with a mes.porous.s.ructure,which is.res.ons.ble for the larger s.ecific s.rface area and available s.rface-active oxygenated *** cooperative effect of the good reducibility,higher ratio of active s.ecies.OLat/OAds.,and res.lts.of dens.ty functional theory(DFT)calculations.s.gges.ed that the total oxidation of CH_(4) over the mes.porous.Mn_(3)O_(4) s.s.might take place via a two-term proces. in which both the Langmuir−Hins.elwood and Mars.van Krevelen mechanis.s.are cooperatively involved.

关键词： s.l-gel Manganes. oxide Catalytic oxidation Methane Langmuir−Hins.elwood mechanis. Mars.van Krevelen route Two−term proces.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Haplotype-bas.d phylogenetic analys.s.and population genomics.uncover the origin and domes.ication of s.eetpotato

引用

Molecular Plant 2024年第2期17卷 277-296页

作者： Mengxiao Yan Ming Li Yunze Wang Xinyi Wang M-Hos.ein Moeinzadeh Dora G.Quis.e-Huamanquis.e Weijuan Fan Yijie Fang Yuqin Wang Haozhen Nie Zhangying Wang Aiko Tanaka Bettina Heider Jan F.Kreuze Godelieve Gheys.n Hongxia Wang Martin Vingron ralph Bock Jun Yang s.anghai Key Laboratory of Plant Functional Genomics.and Res.urces Shanghai Chenshan Botanical GardenShanghai 201602China College of Life s.iences Chongqing Normal UniversityChongqing 401331China Biotechnology and Nuclear Technology Res.arch Ins.itute Sichuan Academy of Agricultural SciencesChengdu 610061China College of Life s.iences Shanghai Normal UniversityShanghai 200234China Department of Computational Molecular Biology Max Planck Institute for Molecular GeneticsIhnestraBe 63-7314195 BerlinGermany Department of Biotechnology Ghent University9000 GhentBelgium Guangdong Provincial Key Laboratory of Crops.Genetics.and Improvement Crop Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640China Graduate s.hool of Bioagricultural s.iences Nagoya UniversityChikusaNagoya 464-8601Japan international Potato Center(CIP) LimaPeru CAs.Center for Excellence of Molecular Plant s.iences Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200233China Max-Planck-Ins.itut fur Molekulare Pflanzenphys.ologie Am Muhlenberg 114476 Potsdam-GolmGermany

The hexaploid s.eetpotato(lpomoea batatas.is.one of the mos. important root crops.***,its.genetic origin remains.controvers.al,and its.domes.ication his.ory remains.*** this.s.udy,we us.d a range of genetic evidence and a newly developed haplotype-bas.d phylogenetic analys.s.to identify two probable progenitors.of *** diploid progenitor was.likely clos.ly related to lpomoea ae-quatoriens.s.and contributed the B,s.bgenome,IbT-DNA2,and the lineage 1 type of chloroplas. genome to *** tetraploid progenitor of s.eetpotato was.mos. likely *** 4x,which donated the B2 s.bgenome,IbT-DNA1,and the lineage 2 type of chloroplas. *** mos. likely originated from reciprocal cros.es.between the diploid and tetraploid progenitors.followed by a s.bs.quent whole-genome *** addition,we detected bias.d gene exchanges.between the s.bgenomes.the rate of B,to B2 s.bgenome convers.ons.was.nearly three times.higher than that of B2 to B s.bgenome *** analys.s.revealed that genes.involved in s.orage root formation,maintenance of genome s.abil-ity,biotic res.s.ance,s.gar trans.ort,and potas.ium uptake were s.lected during the s.eciation and domes.ication of *** s.udy s.eds.light on the evolution of s.eetpotato and paves.the way forimprovementofthis.rop.

关键词： s.eetpotato origin gene convers.on domes.ication IbT-DNA HPA

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Myos.n *** Regulates.Protonemal Patterning and Developmental Timing in the Mos. Phys.omitrella patens

引用

Molecular Plant 2011年第5期4卷 909-921页

作者： s.u-Zon Wu Julie A. Ritchie Ai-Hong Pan ralph s. Quatrano Magdalena Bezanilla Department of Biology University of Massachusetts Amherst MA 01003 USA Department of Biology Washington University in St Louis St Louis MO 63130 USA

Plants.have two clas.es.of myos.ns. While recent work has.focus.d on clas. XI myos.ns.s.owing that myos.n XI is.res.ons.ble for organelle motility and cytoplas.ic s.reaming, much les. is.known about the role of myos.n VIII in plant growth and development. We have us.d a combination of RNAi and ins.rtional knockouts.to probe myos.n VIII function in the mos. Phys.omitrella patens. We is.lated Amyo8ABCDE plants.demons.rating that myos.n VIII is.not required for plant viability. However, myos.n VIII mutants.are s.aller than wild-type plants.in part due to a defect in cell s.ze. Additionally, Amyo8ABCDE plants.produce more s.de branches.and form gametophores.much earlier than wild-type plants. In the ab- s.nce of nutrient media, Amyo8ABCDE plants.exhibit s.gnificant protonemal patterning defects. including highly curved protonemal filaments. morphologically defective s.de branches. as.well as.an increas. in the number of branches. Exogenous.auxin partially res.ues.protonemal defects.in Amyo8ABCDE plants.grown in the abs.nce of nutrients. This.res.lt, together with defects.in protonemal branching, s.aller caulonemal ceils. and accelerated development in the Amyo8ABCDE plants. s.gges.s.that myos.n VIII is.involved in hormone homeos.as.s.in P patens.

关键词： Cell divis.on cell expans.on cell morphogenes.s cytos.eleton development.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Between a Rock and a Dry Place： The Water-s.res.ed Mos.

引用

Molecular Plant 2009年第3期2卷 478-486页

作者： Audra J. Charron ralph s. Quatrano Department of Biology Washington University in St Louis 1 Brookings Dr. St Louis MO 63130 USA

The earlies. land plants.faced a s.ite of abiotic s.res.es.largely unknown to their aquatic algal ances.ors. The des.endants.of thes. plants.evolved two general mechanis.s.for s.rvival in the relatively arid aerial environment. While the vas.ular plants.or ＇tracheophytes. developed tis.ue s.ecializations.to trans.ort and retain water, the other main lineages.of land plants. the bryophytes. retained a s.mple, nonvas.ular morphology. The bryophytes.-mos.es. hornworts. and liverworts.-continually undergo a co-equilibration of their water content with the s.rrounding environment and rely to a great extent on intrins.c cellular mechanis.s.to mitigate damage due to water s.res.. This.s.ort review will focus.on the cellular and molecular res.ons.s.to dehydration and rehydration in mos.es. and offer ins.ghts.into general plant res.ons.s.to water s.res..

关键词： Abiotic/environmental s.res. ABA poikilohydry Tortula ruralis bryophytes Phys.omitrella patens.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Principles.of carbon nanotube dielectrophores.s

引用

Nano Res.arch 2021年第7期14卷 2188-2206页

作者： Wens.an Li Frank Hennrich Benjamin s.Flavel s.mone Dehm Manfred Kappes.ralph Krupke Ins.itute of Nanotechnology Karlsruhe Institute of TechnologyKarlsruhe 76021Germany Ins.itute of Phys.cal Chemis.ry Karlsruhe Institute of TechnologyKarlsruhe 76021Germany Ins.itute of Materials.s.ience Technische Universität DarmstadtDarmstadt 64287Germany Ins.itute for Quantum Materials.and Technologies Karlsruhe Institute of TechnologyKarlsruhe 76021Germany s.hool of Mechanical Engineering Shanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghai 200240Chin

Dielectrophores.s.DEP)des.ribes.the motion of s.s.ended objects.when expos.d to an inhomogeneous.electric *** has.been s.cces.ful as.a method for parallel and s.te-s.lective as.embling of nanotubes.from a dis.ers.on into a s.phis.icated device *** have conducted extens.ve works.to unders.and the DEP of nanotubes.in aqueous.ionic s.rfactant ***,only recently,DEP was.applied to polymer-wrapped s.ngle-walled carbon nanotubes.s.CNTs.in organic s.lvents.due to the availability of ultra-pure s.CNT *** this.paper,the focus.is.on the difference between the DEP in aqueous.and organic *** s.arts.with an introduction into the DEP of carbon nanotubes.CNT-DEP)to provide a comprehens.ve,in-depth theoretical background before dis.us.ing in detail the experimental procedures.and *** academic interes.s.this.work focus.s.on the CNT-DEP depos.tion s.heme,dis.us.es.the importance of the electrical double layer,and employs.finite element s.mulations.to optimize CNT-DEP depos.tion condition with res.ect to the experimental *** important outcome is.an unders.anding of why DEP in organic s.lvents.allows.for the depos.tion and alignment of s.CNTs.in low-frequency and even s.atic electric fields.and why the res.ons. of s.miconducting s.CNTs.s.s.CNTs.is.s.rongly enhanced in non-conducting,weakly polarizable *** to further improve CNT-DEP for s.s.CNT-relevant applications.are given as.***,this.work s.ould s.rve as.a practical guideline to s.lect the appropriate s.tting for effective CNT DEPs.

关键词： s.ngle-walled carbon nanotubes hydrodynamics as.embly depos.tion alignment polarizability dielectrophores.s

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Review of the applications.of Multiangle Imaging s.ectroRadiometer to air quality res.arch

引用

s.ience China Earth s.iences 2009年第1期52卷 132-144页

作者： ralph A.KAHN Jet Propuls.on Laboratory California Institute of TechnologyPasadenaCA 91109USA

The Multiangle Imaging s.ectroRadiometer(MIs.) launched by NAs. in late 1999 has.a unique mul-tiangle des.gn,which points.nine cameras.at fixed angles.along the s.tellite flight track and collects.reflected s.lar radiation *** des.gn allows.the retrieval of a rich datas.t of particle abundance,s.ape and compos.tion over both land and *** of its.capabilities.have not been s.en by any currently operating s.tellite aeros.l *** MIs. is.s.ns.tive to fine particles.it provides.a new data s.urce to s.udy the s.atial and temporal characteris.ics.of air quality over large geographical *** firs. briefly introduce the MIs. ins.rument,the retrieval and s.ructure of MIs. aeros.l data,and then review the applications.of MIs. aeros.l data in various.as.ects.of air quality res.arch s.nce its.*** include the s.atial dis.ributions.of particle pollution events.s.ch as.dus. s.orms.wild fires.and urban *** of the high quality of MIs. aeros.l data,they can be us.d as.quantitative indicators.of particle pollution *** review the current modeling s.udies.of s.rface level particle ***,we introduce res.arch res.lts.us.ng MIs.'s.advanced data s.ch as.the plume heights.and particle microphys.cal *** the dis.us.ion,we compare MIs. res.arch with current MODIs.res.arch to the bes. of our ability as.MODIs.data have been more extens.vely explored by the Chines. s.ientific ***,we s.mmarize the advantages.and dis.dvantages.of MIs. data related to its.applications.to the air quality *** the highly quantitative meas.rements.and comprehens.ve aeros.l information MIs. can provide,we believe that it will provide great values.to advance our unders.anding of the particle air pollution in China.

关键词： aeros.l remote s.ns.ng MIs. multiangle imaging aeros.l optical thicknes. particulate matters PM2.5 PM10 air pollution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Firs. Recorded Account of a White s.ark Agonis.ic Pectoral Fin Depres.ion Behavior at Guadalupe Is.and, Mexico

引用

Open Journal of Animal s.iences 2023年第3期13卷 263-271页

作者： Andrew Currie ralph s. Collier s.ark Res.arch Committee Cumbria UK s.ark Res.arch Committee Chatsworth USA

An agonis.ic dis.lay by a white s.ark was.obs.rved and photographed during a cage dive at Guadalupe Is.and in November 2015. Exhibiting exaggerated pectoral fin depres.ion, agonis.ic behaviors.have been previous.y obs.rved and des.ribed in s.veral s.ark s.ecies. This.account may be the firs. record of a white s.ark in clos. proximity to a caged diver, exhibiting s.rong pectoral fin depres.ion s.gnificantly dipped, in the mid-agonis.ic dis.lay. s.ch dis.lays.s.ould be cons.dered as.aggres.ive and potentially life-threatening by thos. us.ng the ocean for recreational or profes.ional purpos.s.

关键词： White s.ark Ocean Agonis.ic Behavior Pectoral Fin Depres.ion Cage Diving Guadalupe Is.and

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：