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A unified analysis of a micro-beam,droplet and CNT ring adhered on a substrate:Calculation of variation with movable boundaries

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Acta Mechanica Sinica 2013年第1期29卷 62-72页

作者： Jian-Lin Liu re Xia School of Pipeline and Civil Engineering China University of Petroleum School of Power and Mechanical Engineering Wuhan University

In this study, we developed a general method to analytically tackle a kind of movable boundary problem from the viewpoint of energy variation. Having grouped the adhesion of a micro-beam, droplet and carbon nanotube （CNT） ring on a substrate into one framework, we used the developed line of reasoning to investigate the adhesion behaviors of these systems. Based upon the derived governing equations and transversality conditions, explicit solutions involving the critical parameters and morphologies for the three systems are successfully obtained, and then the parameter analogies and common characteristics of them are thor- oughly investigated. The presented method has been verified via the concept of energy release rate in fracture mechanics. Our analyses provide a new approach for exploring the mechanism of different systems with similarities as well as for understanding the unity of nature. The analysis results may be beneficial for the design of nano-structured materi- als, and hold potential for enhancing their mechanical, chemical, optical and electronic properties.

关键词： Variational theory - Transversality condition Beam adhesion Droplet adhesion Carbon nanotube ring adhesion

Taxonomic history and identity of Musa dasycarpa,*** and *** (Musaceae) in Southeast Asia

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植物分类学报 2008年第2期46卷 230-235页

作者： Markku HKKINEN Henry Vre Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Menglun Mengla Yunnan 666303 China Botanic Garden University of Helsinki P.O. Box 44 (Jyrngntie 2) FI-00014 Finland Finnish Museum of Natural History Botanical Museum University of Helsinki P.O. Box 7 (Unioninkatu 44) FI-00014 Finland

Since the initial description, the name Musa dasycarpa Kurz (1867) has been unclear to most botanists. It has usually been synonymized with M. velutina H. Wendl. & Drude (1875). However, although the original diagnosis was very short, 'fruits hairy', it is adequate. Thus, according to Vienna Codes, M. dasycarpa Kurz has priority over M. velutina H. Wendl. & Drude. The aim of this study is to settle the true identity and to update the description of M. dasycarpa Kurz. For that purpose the names M. dasycarpa and M. velutina are typified. In addi-tion, critical notes re.arding M. assamica Bull. are given; it is neotypified here, and considered as conspecific with M. sanguinea Hook. f.

关键词：香蕉科南亚地区分类鉴定野生种质

Stimulants and donors promote megaplasmid pND6-2 horizontal gene transfer in activated sludge

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Journal of Environmental Sciences 2023年第4期126卷 742-753页

作者： Shan Wang Shanshan Li Dan Du Olusegun KAbass Muhammad salman Nasir Wei Yan Department of Environmental Science and Engineering Xi’an Key Laboratory of Solid Waste Recycling and Resource RecoveryXi’an Jiaotong UniversityXi’an 710049China School of Civil and Environmental Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Structures and Environmental Engineering University of AgricultureFaisalabad 38040Pakistan

The activated sludge process is characterized by high microbial density and diversity,both of which facilitate antibiotic resistance gene *** studies have suggested that antibiotic and non-antibiotic drugs at sub-inhibitory concentrations are major inducers of conjugative gene *** self-transmissible plasmid pND6-2 is one of the endogenous plasmids harbored in Pseudomonas putida ND6,which can trigger the transfer of another co-occurring naphthalene-degrading plasmid ***,to illustrate the potential influence of stimulants on conjugative transfer of pND6-2,we evaluated the effects of four antibiotics (ampicillin,gentamycin,kanamycin,and tetracycline) and naphthalene,on the conjugal transfer efficiency of pND6-2 by filter-mating *** findings demonstrated that all stimulants within an optimal dose promoted conjugative transfer of pND6-2from Pseudomonas putida GKND6 to *** KT2440,with tetracycline being the most effective (100μg/L and 10μg/L),as it enhanced pND6-2-mediated intra-genera transfer by approximately one ***,seven AS reactors were constructed with the addition of donors and different stimulants to further elucidate the conjugative behavior of pND6-2 in natural *** stimulants positively affected the conjugal process of pND6-2,while donors reshaped the host abundance in the *** was likely because stimulant addition enhanced the expression levels of conjugation transfer-re.ated ***,Blastocatella and Chitinimonas were identified as the potential receptors of plasmid pND6-2,which was not affected by donor *** findings demonstrate the positive role of sub-inhibitory stimulant treatment on pND6-2 conjugal transfer and the function of donors in re-shaping the host spectrum of pND6-2.

关键词： Antibiotics Naphthalene Donor Conjugative transfer Host range

Investigate the Impact of Dimple Size and Distribution on the Hydrothermal Performance of Dimpled Heat Exchanger Tubes

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Frontiers in Heat and Mass Transfer 2024年第2期22卷 597-613页

作者： Abeer H.Falih Basima salman Khalaf Basim Freegah Mechanical Engineering Department College of EngineeringMustansiriyah UniversityBaghdadIraq

In this study,the primary objective was to enhance the hydrothermal performance of a dimpled tube by addressing areas with low heat transfer compared to other *** accomplish this,a comprehensive numerical investigation was conducted using ANSYS Fluent 2022 R1 software,focusing on different diameters of dimples along the pipe’s length and the distribution of dimples in both in-line and staggered *** simulations utilized the finite elementmethod to address turbulent flowwithin the tube by solving partial differential equations,encompassing re numbers spanning from 3000 to *** study specifically examined single-phase flow conditions,with water utilized as the cooling *** results of the investigation indicated that increasing the reynolds number resulted in higher average Nusselt numbers,pressure drops,the overall performance criterion,and a reduction in average thermal resistance across all models ***,both proposedmodels demonstrated improved heat transfer when compared to the conventional *** of all the models evaluated,the tube featuring staggered dimples(Model B)demonstrated the most notable improvement in the Nu *** exhibited an enhancement of approximately twice the value compared to the conventional *** mean thermal resistance for the tube with dimples in the staggered arrangement(Model B)is 0.0057 k/W,compared to 0.0118 k/W for the traditional *** maximum overall performance criterion for Model-A-and Model-Bis 1.22 and 1.33,respectively.

关键词： Dimpled tube numerical simulation in-line and staggered arrangements overall performance criterion(OPC)

A taxonomic revision of Musa aurantiaca (Musaceae) in Southeast Asia

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植物分类学报 2008年第1期46卷 89-92页

作者： Markku HKKINEN Henry Vre Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Menglun Mengla Yunnan 666303 China Botanic Garden University of Helsinki P.O. Box 44 (Jyrngntie 2) FI-00014 Finland Finnish Museum of Natural History Botanical Museum University of Helsinki P.O. Box 7 (Unioninkatu 44) FI-00014 Finland)

Since the initial description, the name Musa aurantiaca Baker (1893) has been unclear to most botanists. The aim of this study is to settle its true identity and to update the description. The plant is distributed in the regions of Upper Assam and Arunachal Pradesh, India, Northern Myanmar and Tibet, China where it occurs commonly but it is not mentioned in Chinese literature.at all. In this paper, the authors also review the description and the literature history of M. aurantiaca from 1893 to the present. Musa aurantiaca Baker is typified here.

关键词：香蕉科东南亚分类学野生香蕉芭蕉

A Mode-Switching Motion Control System for reactive Interaction and Surface Following Using Industrial Robots

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IEEE/CAA Journal of Automatica Sinica 2018年第3期5卷 670-682页

作者： Danial Nakhaeinia Pierre Payeur Robert Laganière School of Electrical Engineering and Computer Science University of Ottawa

This work proposes a sensor-based control system for fully automated object detection and exploration(surface following) with a redundant industrial robot. The control system utilizes both offline and online trajectory planning for reactive interaction with objects of different shapes and color using RGBD vision and proximity/contact sensors feedback where no prior knowledge of the objects is available. The RGB-D sensor is used to collect raw 3D information of the environment. The data is then processed to segment an object of interest in the scene. In order to completely explore the object, a coverage path planning technique is proposed using a dynamic 3D occupancy grid method to generate a primary(offline) trajectory. However, RGB-D sensors are very sensitive to lighting and provide only limited accuracy on the depth measurements. Therefore, the coverage path planning is then further assisted by a real-time adaptive path planning using a fuzzy self-tuning proportional integral derivative(PID)controller. The latter allows the robot to dynamically update the 3D model by a specially designed instrumented compliant wrist and adapt to the surfaces it approaches or touches. A modeswitching scheme is also proposed to efficiently integrate and smoothly switch between the interaction modes under certain conditions. Experimental results using a CRS-F3 manipulator equipped with a custom-built compliant wrist demonstrate the feasibility and performance of the proposed method.

关键词： Adaptive control fuzzy-PID controller manipulator control motion planning surface following

THreE DIMENSIONAL DYNAMIC ELASTICPLASTIC ANALYSIS OF THE INTERACTION OF A SET OF PERCUSSION BITS WITH ROCK MASSES

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Acta Mechanica Solida Sinica 1995年第4期8卷 364-374页

作者： Song, SC Knasmillner, re INNER MANGOLIA reS INST MET POB 4BAOTOU 014034PEOPLES R CHINA VIENNA TECH UNIV INST MECHA-1040 VIENNAAUSTRIA

A three dimensional dynamic elastic-plastic finite element analysis of the interaction of percussion bits with rock masses is presented. The dynamic contact problem was investigated with the numerical method developed for high velocity impact calculations[1]. The numerical analysis was carried out for three simultaneously loaded percussion bits arranged on a straight line on the rock surface, the loading time was kept constant throughout this work. The numerical calculation for various strengths of the dynamic load tm the percussion bits shows that a critical minimum dynamic load exists for the generation of plastic deformations in the rock. For this critical value of the load the maximum normal stress of the longitudinal wave in the percussion bit exceeds the yield stress of the rock mass.

关键词： rock masses percussion bits numerical analysis

A new look on wetting models:continuum analysis

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Science China(Physics,Mechanics & Astronomy) 2012年第11期55卷 2158-2166页

作者： LIU JianLin XIA re ZHOU XiaoHua School of Pipeline and Civil Engineering China University of PetroleumQingdao 266555China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China Department of Mathematics and Physics Fourth Military Medical UniversityXi’an 710032China

In this study,we considered the wetting phenomenon on a general substrate from a new viewpoint of continuum *** analyses first show how the Wenzel and the Cassie models deviate the practical results in some special substrates,and then elucidate the mechanism of the triple contact line(TCL) *** upon variational theory of the total free functional dealing with the movable boundary condition,we show that the macroscopic contact angle(MCA) expression is the corresponding transversality *** manifests that the MCA depends only on the chemical and geometric property at the TCL,and is not affected by the gravity of the droplet and the contact area beneath the *** continuum model also shows the exploration of the pinning effect on a sharp wedge or the interface between two different *** investigation will help designing super-hydrophobic materials for novel micro-fluidic devices.

关键词： continuum field energy functional transversality condition mechanism-based model triple line moving

A Shortest-Path Tree Approach for Routing in Space Networks

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China Communications 2020年第7期17卷 52-66页

作者： Olivier De Jonckère Juan A.Fraire Technische Universitat Dresden 01187Germany CONICET-Univerisidad Nacional de Córdoba 5000Argentina Saarland University Saarland Informatics CampusSaarbrückenGermany

A new space era is bringing deployments of thousands of networked assets in near-Earth and ***-Tolerant Networking(DTN)protocols and algorithms such as Contact Graph Routing(CGR)are state-of-the-art technologies certainly capable of achieving this ambitious ***,in this paper,we highlight and analyze the roots of current scalability limits of CGR,to then propose more efficient *** particular,we leverage a different graph modeling approach that enables optimizations such as priority queues and spanning-tree searches in the core route determination *** such abstract data types are difficult to adapt to CGR,we incorporate them into a novel Shortest-Path Tree Approach for Routing in Space Networks(SPSN),which is presented as a compute-efficient *** paper thoroughly describes the SPSN approach including route object modeling,capacity-oriented search,and potential route management *** evaluations analyzed in this paper present significant evidence that SPSN outperforms legacy CGR in more than an order of magnitude in contact plans comprising thousands of contacts.

关键词： bringing thoroughly enable