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海岸工程 1996年第3期15卷 70-75页

作者： i.a.svendsen 高恒庆丹麦格林比技术大学流体动力学和水利工程研究所

介绍了不规则波的生成方法，其中长波、反射及三维波是关键。对波—流合成做了分析，讨论了水波中与雷诺数有关的现象的模拟。

关键词：海岸工程海洋动力学波浪不规则波物理模式

Thermodynamic and rate variational formulation of models for inhomogeneous gradient materials with microstructure and application to phase field modeling

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Acta Mechanica Sinica 2015年第2期31卷 162-172页

作者： Svyatoslav Gladkov Bob svendsen Material Mechanics RWTH Aachen Aachen Germany Microstructure Physics and Alloy Design Max-Planck-Institut fur Eisenforschung DusseldorfGermany

in this work,thermodynamic models for the energetics and kinetics of inhomogeneous gradient materials with microstructure are formulated in the context of continuum thermodynamics and material *** simplicity,attention is restricted to isothermal *** materials of interest here are characterized by（1） first- and secondorder gradients of the deformation field and（2） a kinematic microstructure field and its gradient（e.g.,in the sense of director,micromorphic or Cosserat microstructure）.Material inhomogeneity takes the form of multiple phases and chemical constituents,modeled here with the help of corresponding phase *** requirements together with the dissipation principle result in the reduced model field and constitutive *** cases of these include the wellknown Cahn-Hilliard and Ginzburg-Landau *** the last part of the work,initial boundary value problems for this class of materials are formulated with the help of rate variational methods.

关键词： Continuum thermodynamics Material inhomogeneity Conservative Non-conservative phase fields

EFFECT OF SURFACE ENERGY ON DiSLOCATiON-iNDUCED FiELD iN HALF-SPACE WiTH APPLiCATiON TO THiN FiLM-SUBSTRATE SYSTEMS

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Acta Mechanica Solida Sinica 2009年第5期22卷 436-442页

作者： Ganyun Huang Bob svendsen Zhixing Lu institute of Mechanics Dortmund University of Technology 44221 Dortmund Germany Sehool of Mechanical Engineering Tianjin University Tianjin 300072 China Department of Mechanical Engineering University of Colorado at Boulder Colorado USA

in this work the elastic field of an edge dislocation in a half-space with the effect of surface energy has been obtained. The elastic field is then used to study the image force on the dislocation, the critical thickness for dislocation generation in epitaxial thin films with strain mismatch and the yielding strength of thin films on substrates. The results show that the image forces on the dislocation deviate from the conventional solutions when the distance of the dislocation from the free surface is smaller than several times of the characteristic length. Also due to the effect of surface energy, the critical thickness for dislocation generation is smaller than that predicted by the conventional elastic solutions and the extent of the deviation depends on the magnitude of mismatch strain. in contrast, the effect of surface energy on the yielding strength for many practical thin films can be neglected except for some soft ones where the characteristic length is comparable to the thickness.

关键词： thin film surface energy effect dislocation half-space critical thickness yielding strength

Experimental Determination and Modeling of Bubble Size Distributions in Bubble Columns

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Chinese Journal of Chemical Engineering 1998年第1期6卷 33-45页

作者： H.F.svendsen 罗和安 K.W.Hjarbo H.A.Jakobsen Department of Chemical Engineering Norwegian University of Science and Technology Department of Chemical Engineering Xiangtan University SiNTEF Applied Chemistry DNMi P.O.Box 43Blindern

Using a five point conductivity technique local values of bubble size,bubble velocity and gas fractionhave been experimentally determined in a 288 mmiD and 4.3 m high bubble column as a function of axial andradial position for the air/water and CO2/N2/aqueous MDEA *** experimental results are comparedwith predictions from a fundamental two-fluid *** implementation of a non-steady lateral drag term inthe two-fluid model has been *** addition to improving the physical realism of the model,it is found togive slight improvements in the predictions of the distributions of local bubble *** of bubble size arefound in reasonable agreement with experimental values in the heterogeous flow regime,whereas they are stil1found to be unreliable at low gas *** void predictions are found in reasonable agreement with experi-mental values,but deviations occur in the homogeneous flow regime towards the *** is attributed to defi-ciencies in the simplified bubble size

关键词： Bubble column bubble size distribution volumetric velocity gas fraction two-fluid model

Simulation by CMiP5 Models of the Atlantic Multidecadal Oscillation and its Climate impacts

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Advances in Atmospheric Sciences 2016年第12期33卷 1329-1342页

作者： Zhe HAN Feifei LUO Shuanglin Li Yongqi GAO Tore FUREViK Lea svendsen Key Laboratory of Regional Climate-Environment for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China Nansen-Zhu international Research Centre and Climate Change Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate Research Bergen 5006 Norway Geophysical institute University of Bergen and BjerknesCentre for Climate Research Bergen 5007 Norway

This study focuses on the climatic impacts of the Atlantic Multidecadal Oscillation （AMO） as a mode of internal vari- ability. Given the difficulties involved in excluding the effects of external forcing from internal variation, i.e., owing to the short record length of instrumental observations and historical simulations, we assess and compare the AMO and its related climatic impacts both in observations and in the ＂Pre-industrial＂ experiments of models participating in CMiP5. First, we evaluate the skill of the 25 CMiP5 models＇＂Historical＂ simulations in simulating the observational AMO, and find there is generally a considerable range of skill among them in this regard. Six of the models with higher skill relative to the other models are selected to investigate the AMO-related climate impacts, and it is found that their ＂Pre-industrial＂ simulations capture the essential features of the AMO. A positive AMO favors warmer surface temperature around the North Atlantic, and the Atlantic iTCZ shifts northward leading to more rainfall in the Sahel and less rainfall in Brazil. Furthermore, the results confirm the existence of a teleconnection between the AMO and East Asian surface temperature, as well as the late withdrawal of the indian summer monsoon, during positive AMO phases. These connections could be mainly caused by internal climate variability. Opposite patterns are true for the negative phase of the AMO.

关键词： Atlantic Multidecadal Oscillation CMiP5 internal climate variability climate impacts

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鼓泡床中的气泡尺寸分布

化工学报 1995年第5期46卷 539-544页

作者：罗和安 HallvardF.svendsen 湘潭大学化学工程系湘潭411105 DepartmentofChemicalEngineering NorwegianInstituteofTechnology

根据气泡聚并和破裂速率模型,提出一个描述鼓泡床中气泡尺寸分布的总体平衡(Population Balance)模型。该模型可预计鼓泡床中气泡尺寸分布随床高的变化。对空气-水体系的模拟结果与实测结果吻合较好。

关键词：鼓泡床气泡尺寸分布气泡聚并气泡破裂

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鼓泡床反应器中液体循环的模拟

化工学报 1995年第4期46卷 458-463页

作者：罗和安 HallvardF.svendsen 湘潭大学化学工程系湘潭411105 挪威工学院化学工程系

应用分离流概念对气液鼓泡床反应器中的两相流体动力学进行了理论分析,从而建立了一个基于机理的液体循环的数学模型。根据这个模型,对影响液体循环的诸因素及部分实例进行了模拟计算,其结果与实验结果吻合很好。

关键词：鼓泡床液体循环模拟反应器

BUBBLE SiZES AND HOLDUP STRUCTURE iN BUBBLE COLUMNS DETERMiNED BY DYNAMiC GAS DiSENGAGEMENT

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Chinese Journal of Chemical Engineering 1996年第2期4卷 59-70页

作者：罗和安 Kai Hjarbo Hallvard svendsen Department of Chemical Engineering Norwegian Institute of Technology 7034 Trondheim Norway

A new model for determining bubble size distributions in bubble columns by the dynamic gasdisengagement(DGD)technique is *** is based on an idea of non-uniform steady statedirstribution of bubble *** the axial non-uniformity,this model gives axial gasholdup *** assuming an axially homogeneous dispersion,a radial gas holdup distributioncan be *** Sauter mean diameters or specific interfacial areas for several systems areestimated by the *** results for an air-water system agree with those measured by afive-point conductivity probe *** obtained axial gas holdup distributions agree well withreported measurements and the radial gas holdup distributions are also reasonable.

关键词： bubble size gas holdup measurement dynamic gas disengagement

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波浪的物理模型

海岸工程 1996年第2期15卷 76-90页

作者： svendsen i.A. 高恒庆

介绍了常用的实验室造波机原理，讨论了波浪模拟的流体力学问题。

关键词：波浪物理模型波浪模拟流体力学

Effects of low-oxygen conditions on embryo growth in the painted turtle,Chrysemys picta

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integrative Zoology 2017年第2期12卷 148-156页

作者： Gerardo A.CORDERO Matthew L.KARNATZ Jon C.svendsen Eric J.GANGLOFF Department of Ecology Evolutionand Organismal BiologyIowa State UniversityAmesIowaUSA Technical University of Denmark National Institute of Aquatic ResourcesFreshwater FisheriesSilkeborgDenmark interdisciplinary Centre of Marine and Environmental Research University of PortoPortoPortugal

Low-oxygen conditions(hypoxia;<21%O_(2))are considered unfavorable for growth;yet,embryos of many vertebrate taxa develop successfully in hypoxic subterranean *** enhanced tolerance to hypoxia has been demonstrated in... 详细信息

Low-oxygen conditions(hypoxia;idered unfavorable for growth;yet,embryos of many vertebrate taxa develop successfully in hypoxic subterranean *** enhanced tolerance to hypoxia has been demonstrated in adult reptiles,such as in the painted turtle(Chrysemys picta),its effects on sensitive embryo life stages warrant *** tested the hypothesis that short-term hypoxia negatively affects growth during day 40 of development in ***,when O_(2) demands are highest in embryos.A brief,but severe,hypoxic event(5%O_(2) for 0.5 h)moderately affected embryo growth,causing a 13%reduction in mass(relative to a normoxic control).The same condition had no effect during day 27;instead,a nearly anoxic event(1%O_(2) for 72 h)caused a 5%mass *** embryos survived the egg incubation *** study supports the assumption that reptilian embryos are resilient to intermittently low O_(2) in subterranean *** work is needed to ascertain responses to suboptimal O_(2) levels while undergoing dynamic changes in developmental physiology.

关键词： embryo metabolism embryo respiration growth rate nest environment oxygen consumption rate