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Acta Mechanica Sinica 2015年第5期31卷 750-761页

作者： Xu Long fei ge Youshi Hong School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical University State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of Sciences

The research progress of a novel traffic solution,a submerged floating tunnel（SFT）,is reviewed in terms of a study approach and loading *** existing publications,the buoyancy-weight ratio（BWR） is usually ***,BWR is a critical structural parameter that tremendously affects the dynamic behaviour of not only the tunnel tube itself but also the cable *** the context of a SFT prototype（SFTP） project in Qiandao Lake（Zhejiang Province,China）,the importance of BWR is illustrated by finite element analysis and subsequently,an optimized BWR is proposed within a reasonable range in the present *** the numerical model,structural damping is identified to be of *** damping and the corresponding Rayleigh coefficients are attained through a sensitivity study,which shows that the adopted damping ratios are fairly suitable for ***,the human sense of security is considered by quantifying the comfort index,which helps further optimize BWR in the SFTP structural parameter design.

关键词： Submerged floating tunnel Buoyancy-weight ratio Water wave and current loads Dynamic response Human security sense Comfort index

An experimental investigation of dual-resonant and non-resonant responses for vortex-induced vibration of a long slender cylinder

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Science China(Physics,Mechanics & Astronomy) 2014年第2期57卷 321-329页

作者： WU XiaoDong ge fei HONG YouShi College of Mechanics Taiyuan University of Technology State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of Sciences

Experimental results of the dual-resonant and non-resonant responses are presented for vortex-induced vibrations(VIV)of a long slender *** cylinder has a diameter of 10mm and a length of 3.31 m,giving an aspect ratio of *** cylinder was towed by a carriage with the velocity up to 1.5 m/s,with the Reynolds number varying from 2500 to *** different weights were used to provide the initial *** resonance means that resonance occurs simultaneously in both the cross-flow(CF)and in-line(IL)*** experiments were conducted in two *** the first stage,dual-resonant dynamic features of the cylinder subjected to vortex-induced excitation were *** features of CF and IL vibration amplitude,motion orbits,phase angle differences,dominant frequencies and mode order numbers are *** the second stage of the experiments,particular emphasis was placed on non-resonant dynamic *** variation of multi-mode modal displacement amplitudes was investigated in detail.

关键词： vortex-induced vibrations long slender cylinder dual-resonant responses non-resonant responses

Effects of tension on vortex-induced vibration(ⅥⅤ) responses of a long tensioned cylinder in uniform flows

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Acta Mechanica Sinica 2017年第1期33卷 1-9页

作者： Ling Kang fei ge Xiaodong Wu Youshi Hong Institute of Mechanics Chinese Academy of SciencesNo. 15 Beisihuan Xi Road Beijing 100190 China

The effects of tension on vortex-induced vibration (VIV) responses for a tension-dominated long cylinder with an aspect ratio of 550 in uniform flows are experimentally investigated in this paper. The results show that elevated tension suppresses fluctuations of maximum displacement with respect to flow velocity and makes chaotic VIV more likely to appear. With respect to periodic VIV, if elevated tension is applied, the dominant vibration frequency in the in-line (IL) direction will switch from a fundamental vibration frequency to twice the value of the fundamental vibration frequency, which results in a ratio of the dominant vibration frequency in the IL direction to that in the cross-flow direction of 2.0. The suppression of the elevated tension in the fluctuation of the maximum displacement causes the axial tension to become an active control parameter for the VIV maximum displacement of a tension-dominated long riser or tether of an engineering structure in deep oceans. However, the axial tension must be optimized before being used since the high dominant vibration frequency due to the elevated tension may unfavorably affect the fatigue life of the riser or tether.

关键词： Tension effect Maximum displacement Dominant vibration frequency Chaos

Preparation of ultrafine chitosan particles by reverse microemulsion

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China Particuology 2007年第6期5卷 384-390页

作者： Guogen Liu Lei Shao fei ge Jianfeng Chen Key Lab for Nanomaterials Ministry of Education Beijing University of Chemical Technology Beijing 100029 China Research Center of Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical Technology Beijing 100029 China

Ultrafine chitosan particles were prepared by reverse microemulsion consisting of water, Triton X-100, octanol and cyclohexane. Two methods of preparing ultrafine chitosan particles were adopted and compared using TEM and IR, and possible mechanisms for the formation of ultrafine chitosan particles were proposed. Experimental results show that the method which combined ionic gelation and cross-linking gave uniformly sized chitosan nanoparticles with an average diameter of 92 nm, while the cross-linking without ionic gelation produced spindly chitosan particles with an average length of 943 nm and width of 188 nm.

关键词： Chitosan Ultrafine particles Microemulsion

Shear flow induced vibrations of long slender cylinders with a wake oscillator model

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Acta Mechanica Sinica 2011年第3期27卷 330-338页

作者： fei ge Wei Lu Lei Wang You-Shi Hong State Key Laboratory of Nonlinear Mechanics Institute of Mechanics CAS 100190 Beijing China

A time domain model is presented to study the vibrations of long slender cylinders placed in shear flow. Long slender cylinders such as risers and tension legs are widely used in the field of ocean engineering. They are subjected to vortex-induced vibrations（VIV） when placed within a transverse incident flow. A three dimensional model coupled with wake oscillators is formulated to describe the response of the slender cylinder in cross-flow and in-line directions. The wake oscillators are distributed along the cylinder and the vortex-shedding frequency is derived from the local current velocity. A non-linear fiuid force model is accounted for the coupled effect between cross-flow and in-line vibrations. The comparisons with the published experimental data show that the dynamic features of VIV of long slender cylinder placed in shear flow can be obtained by the proposed model,such as the spanwise average displacement,vibration frequency,dominant mode and the combination of standing and traveling waves. The simulation in a uniform flow is also conducted and the result is compared with the case of nonuniform flow. It is concluded that the flow shear characteristic has significantly changed the cylinder vibration behavior.

关键词： Vortex-induced vibration Vortex-induced wave Shear flow Wake oscillator Long slender cylinder

Flow-induced vibrations of long circular cylinders modeled by coupled nonlinear oscillators

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1086-1093页

作者： ge fei LONG Xu WANG Lei HONG YouShi State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

The dynamics of long slender cylinders undergoing vortex-induced vibrations (VIV) is studied in this work. Long slender cylinders such as risers or tension legs are widely used in the field of ocean engineering. When the sea current flows past a cylinder, it will be excited due to vortex shedding. A three-dimensional time domain model is formulated to describe the response of the cylinder, in which the in-line (IL) and cross-flow (CF) deflections are coupled. The wake dynamics, including in-line and cross-flow vibrations, is represented using a pair of non-linear oscillators distributed along the cylinder. The wake oscillators are coupled to the dynamics of the long cylinder with the acceleration coupling term. A non-linear fluid force model is accounted for to reflect the relative motion of cylinder to current. The model is validated against the published data from a tank experiment with the free span riser. The comparisons show that some aspects due to VIV of long flexible cylinders can be reproduced by the proposed model, such as vibrating frequency, dominant mode number, occurrence and transition of the standing or traveling waves. In the case study, the simulations show that the IL curvature is not smaller than CF curvature, which indicates that both IL and CF vibrations are important for the structural fatigue damage.

关键词： vortex-induced vibration (VIV) vortex-induced wave (VIW) wake oscillator long cylinder fluid-structure interaction

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文学史研究视野中的先锋小说

南方文坛 2007年第1期 83-88页

作者：格非李建立清华大学文学院中国人民大学文学院

这是一个对话专栏,一开始就打算和文学批评式的访谈区别开来。我们希望在观照具体的创作现象时体现出一种更为宽广和理性的文学史视野,但这不是要排斥直觉、趣味和审美判断等文学批评格外倚重的质素在对话中的灵光闪现,而是将“新时期... 详细信息

这是一个对话专栏,一开始就打算和文学批评式的访谈区别开来。我们希望在观照具体的创作现象时体现出一种更为宽广和理性的文学史视野,但这不是要排斥直觉、趣味和审美判断等文学批评格外倚重的质素在对话中的灵光闪现,而是将“新时期”文学实践及其伴生的文学观念和潜在标准"陌生化"为一种"知识",同时将之重新放置在具体的历史语境中予以考量。“对话者”主要是当代著名作家和文学史研究者。因此,某种意义上它更为关注的也许不是这些作家个人的“成长史”或“创作史”,而是它们与当时文学思潮、圈子时尚、批评氛围等等之间的内在关联,后者是怎样进入作家的创作过程的?又是怎样被置换为作家个人的艺术体验并最终构筑为他们的“文学世界”的?我们相信,随着时间的推移,“新时期文学”已经很难再被指认为作家们的当下语境,它与作家当年的言说发生了根本的剥离,这就使人更清楚地看到了当年各种文学流派和作家涌现文坛的壮观情形,以及一位作家与他们的“文学史”之间的历史隐密。所以,这项工作既可以看作是对“新时期”文学的一种疏理,也可以看作是文学史视野中的“作家研究”,还可以看作是作家们的“文学史回顾”——这里的“对话”,实际是作家与文学史的“对话”。

关键词：先锋小说翻译文学文学史作家文学批评视野

Blockage of ATPase-mediated energy supply inducing metabolic disturbances in algal cells under silver nanoparticles stress

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Journal of Environmental Sciences 2023年第9期131卷 141-150页

作者： Ruohua Qu Mi Chen Jingfu Liu Qiting Xie Na Liu fei ge Department of Environment College of Environment and ResourcesXiangtan UniversityXiangtan 411105China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Adenosine triphosphate(ATP)generation of aquatic organisms is often subject to nanoparticles(NPs)stress,involving extensive reprogramming of gene expression and changes in enzyme activity accompanied by metabolic ***,little is known about the mechanism of energy supply by ATP to regulate the metabolism of aquatic organisms under NPs ***,we selected extensively existing silver nanoparticles(AgNPs)to investigate their implications on ATP generation and relevant metabolic pathways in alga(Chlorella vulgaris).Results showed that ATP content significantly decreased by 94.2%of the control(without AgNPs)in the algal cells at 0.20 mg/L AgNPs,which was mainly attributed to the reduction of chloroplast ATPase activity(81.4%)and the downregulation of ATPase-coding genes atpB and atpH(74.5%-82.8%)in *** dynamics simulations demonstrated that AgNPs competed with the binding sites of substrates adenosine diphosphate and inorganic phosphate by forming a stable complex with ATPase subunit beta,potentially resulting in the reduced binding efficiency of ***,metabolomics analysis proved that the ATP content positively correlated with the content of most differential metabolites such as D-talose,myo-inositol,and *** remarkably inhibited ATPinvolving metabolic pathways,including inositol phosphate metabolism,phosphatidylinositol signaling system,glycerophospholipid metabolism,aminoacyl-tRNA biosynthesis,and glutathione *** results could provide a deep understanding of energy supply in regulating metabolic disturbances under NPs stress.

关键词： Adenosine triphosphate Metabolomics Molecular dynamics simulations Nanoparticles Algae

Effects of luteinizing hormone and androgen on the development of rat progenitor Leydig cells in vitro and in vivo

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Asian Journal of Andrology 2013年第5期15卷 685-691页

作者： Jing-Jing Guo Xue Ma Claire Q F Wang Yu-fei ge Qing-Quan Lian Dianne O Hard Yu-fei Zhang Qiang Dong Yun-fei Xu Ren-Shan ge The 2nd Affiliated Hospital Wenzhou Medical College Wenzhou 325027 China Population Council & Rockefeller University New York NY 10065 USA Department of Urology West China Hospital Sichuan University Chengdu 610041 China Mudanjiang Medical College M udanjiang 157011 China Department of Urology the Affiliated 10th People's Hospital of Tongji University Shanghai 200072 China

Progenitor Leydig cells are derived from stem cells. The proliferation and differentiation of progenitor Leydig cells significantly contributes to Leydig cell number during puberty. However, the regulation of these processes remains unclear. The objective of the present study was to determine whether luteinizing hormone （LH） or androgen contributes to the proliferation and differentiation of progenitor Leydig cells. Fourteen-day-old male Sprague-Dawley rats were treated for 7 days with NalGlu, which is a gonadotropin- releasing hormone antagonist, to reduce the secretion of LH in the pituitary and thus, androgen in the testis. Rats were co-administered with LH or 7a-methyl-nortestosterone （MENT）, which is an androgen resistant to metabolism by 5a-reductase 1 in progenitor Leydig cells, and the subsequent effects of LH or androgen were measured. 3H-Thymidine was also intravenously injected into rats to study thymidine incorporation in progenitor Leydig cells. Progenitor Leydig cells were examined. NalGlu administration reduced progenitor Leydig cell proliferation by 83%. In addition, LH or MENT treatment restored Leydig cell proliferative capacity to 73% or 50% of control, respectively. The messenger RNA levels of proliferation-related genes were measured using real-time PCR. The expression levels of Igfl, Lifr, Pdgfra, Bcl2, Ccnd3and Pcnawere upregulated by MENT, and those of Pdgfra, Ccnd3and Pcnawere upregulated by LH. Both LH and MENT stimulated the differentiation of progenitor Leydig cells in vitro. We concluded that both LH and MENT were involved in regulating the development of progenitor Leydig cells.

关键词： l utei nizi ng hormone progenitor Leydig cell proliferation testosterone

Aggregation-induced emission materials for nonlinear optics

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Aggregate

Aggregate 2021年第3期2卷 21-39页

作者： Xiao Han fei ge Jialiang Xu Xian-He Bu School of Materials Science and Engineering National Institute for Advanced MaterialsNankai UniversityTianjinP.R.China

Aggregation-induced emission(AIE)is a vital photophysical phenomenon that the luminogens in the concentrated or aggregated cases will engender the dramatically boosted emission in comparison with the dispersive *** this extraordinary emitting capacity exactly resolves the aggregation-caused quenching(ACQ)situations residing in the traditional luminophores,the booming AIE luminogens have drawn tremendous interest owing to their advanced performances and colossal potential applications in various *** exploitations of AIE molecules also drive the research interests in the midst of these AIE materials toward the nonlinear optical(NLO)*** combination of AIE and NLO effects have nurtured some unforeseen properties of AIE materials and extended their application ***,some NLO-active AIE materials have been wielded in many crucial applications,for example,optical limiting,laser,bioimaging,and photodynamic ***,the impacts of aggregate on the NLO effect also deserve deep considerations and pursuits,and the modifications of aggregates promise an easy,efficient,and prompt avenue to tune the NLO properties of *** recent achievements and progress in the NLO properties of AIE materials have been summarized in this *** second-order and third-order NLOs of the AIE materials have been introduced and their correlative applications have been discussed.

关键词： aggregate aggregation-induced emission nonlinear optics