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Advances in Manufacturing 2021年第1期9卷 145-159页

作者： lu-Yi Han Ri-Liang liu Xin-feng liu School of Mechanical Engineering Shandong UniversityJinan 250061People's Republic of China Key Laboratory of High Efficiency and Clean Mechanical Manufacture Shandong UniversityJinan 250061People's Republic of China National Demonstration Center for Experimental Mechanical Engineering Education Shandong UniversityJinan 250061People's Republic of China

Whirling has been adopted for the cost-effective machining of blade-shape components in addition to traditional end milling and flank milling *** satisfy the requirements of rotary forming in the blade whirling process,the workpiece must be clamped at both ends in suspension and rotated slowly during machining,which complicates the *** study aims to identify the dynamic characteristics within the blade whirling operation and present strategies for stability *** this study,the dynamic characteristics of a whirling system are modeled by assuming symmetric and asymmetric *** prediction frequency response function(FRF)results are compared with experimental ***,semi-discretization stability lobe diagrams(SLDs)obtained using the dynamic parameters of these models are investigated *** results show that the asymmetric model is more suitable for describing the whirling system,whereas the symmetric model presents limitations associated with the frequency range and location of measuring ***,a set of airfoil propeller blade whirling operations is conducted to verify the prediction accuracy.

关键词： Whirling Asymmetric frequency response function(FRF) Stability lobe diagrams(SLD) Semi-discretization method

Stage separation of recoverable liquid launch vehicle by using moving pulsating ball analogue for propellant sloshing

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Chinese Journal of Aeronautics 2024年第2期37卷 360-370页

作者： yu lu Baozeng yuE Bailong HAO Bole MA feng liu yuanyuan CHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

In the process of stage separation of recoverable liquid launch vehicles,because of the large amount of residual fuel in the storage tanks,the influence of liquid sloshing on separation safety must be *** calculation simplicity and operation practicability,the Moving Pulsating Ball Model(MPBM)of large amplitude liquid sloshing is introduced into the calculation of launch vehicle stage *** the dynamic equation of the model with the energy relationship during"breathing movement",the formula calculating the force of liquid on the rigid body is *** with the calculations of commercial CFD calculation software,the accuracy of MPBM model is ***,all the external forces and moments are applied to the rigid body of the stages,so that the translational and rotational dynamic equations of the stages are obtained *** to the relative position of the two stages,the geometric shape of the interstage section and the engine of the second stage,the minimum clearance in the separation process can be decided to guarantee that the separation process is safe.

关键词： Moving Pulsating Ball Model(MPBM) Dynamics of stage separation Large amplitude sloshing Recoverable liquid launch vehicle Flight dynamics

Characterization of the structural details of residual austenite in the weld metal of a 9Cr1MoNbV welded rotor

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 563-568页

作者： Xia liu Hui-jun Ji Peng liu Peng Wang feng-gui lu yu-lai Gao Department of Mechanical Engineering Tsinghua University Shanghai Turbine Plant of Shanghai Electric Power Generation Equipment Co. Ltd. School of Materials Science and Engineering Shanghai University School of Materials Science and Engineering Shanghai Jiao Tong University

The existence of residual austenite in weld metal plays an important role in determining the properties and dimensional accuracy of welded rotors. An effective corrosive agent and the metallographic etching process were developed to clearly reveal the characteristics of residual austenite in the weld metal of a 9Cr1MoNbV welded rotor. Moreover, the details of the distribution, shape, length, length-to-width ratio, and the content of residual austenite were systematically characterized using the Image-Pro Plus image analysis software. The results revealed that the area fraction of residual austenite was approximately 6.3% in the observed weld seam; the average area, length, and length-to-width ratio of dispersed residual austenite were quantitatively evaluated to be （5.5 ± 0.1）μm2, （5.0 ± 0.1）μm, and （2.2 ± 0.1）, re-spectively. The newly developed corrosive agent and etching method offer an appropriate approach to characterize residual austenite in the weld metal of welded rotors in detail.

关键词： steel research austenite characterization weld metal color metallography

From non-carbon host toward carbon-free lithium-sulfur batteries

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Nano Research 2024年第3期17卷 1337-1365页

作者： Yanqi feng Hui liu Qiongqiong lu School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Institute of Materials Henan Key Laboratory of Advanced Conductor MaterialsHenan Academy of SciencesZhengzhou 450046China Leibniz Institute for Solid State and Materials Research(IFW)Dresden e.V. Helmholtzstraβe 2001069 DresdenGermany School of Materials&Environment Engineering Chengdu Technological UniversityChengdu 611730China

Lithium-sulfur(Li-S)batteries with advantages of high energy densities(2600 Wh·kg^(-1)/2800 Wh·L^(-1))and sulfur abundance are regarded as promising candidates for next-generation high-energy ***,the conventional carbon host used in sulfur cathodes suffers from poor chemical adsorption towards Li-polysulfides(LPS)in liquid electrolyte and sluggish redox kinetics,leading to low capacity and rate ***,carbon host used in Li metal anode with the intrinsic property of poor lithiophilicity and high Li-nucleation barrier gives rise to uncontrollable dendrite growth and further battery ***,non-carbon hosts with chemical adsorption toward LPS and catalytic activity for accelerating LPS redox conversion as well as lithiophilic property for guiding uniform Li deposition are proposed and demonstrated a high efficiency in both sulfur cathodes and Li metal *** this review,the principle and challenges of Li-S batteries are first presented,then recent work using non-carbon hosts in Li-S batteries is summarized comprehensively,and the mechanism of non-carbon host in improving sulfur utilization and stabilizing Li metal anode is discussed in ***,remaining challenges and outlook on the implementation of non-carbon host for practical carbon-free Li-S batteries are also provided.

关键词： sulfur cathode Li metal anode polysulfides adsorption catalytic effect Li dendrite carbon-free lithium-sulfur batteries

Consensus of Single Integrator Multi-Agent Systems with Unbounded Transmission Delays

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Journal of Systems Science & Complexity 2019年第3期32卷 778-788页

作者： XU Xiang liu lu feng Gang Department of Biomedical Engineering City University of Hong Kong

This paper investigates the consensus problem of single integrator multi-agent systems with unbounded time-varying transmission delays and fixed di rec ted topology. A dist ributed cont roller is proposed taking into consideration the unbounded transmission delays. It is shown that the consensus problem can be solved via the proposed controller under the spanning tree assumption and the nocycle assumption. The authors characterize the no-cycle assumption and prove the consensus of the concerned multi-agent systern with an induction procedure. Two simulation examples are provided, one to illustrate the effectiveness of our result and the other to show the necessity of the no-cycle assumption.

关键词： Consensus multi-agent systems unbounded transmission delays

An Assessment of Changes in Bioclimatic Types in Sichuan Province, 1961-2010

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Journal of Mountain Science 2015年第1期12卷 145-153页

作者： lu Ya-feng liu Yan-Qing XU Pei WANG yu-kuan liu yuan Institute of Mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences Foreign Economic Cooperation Office Ministry of Environmental Protection

Assessing the impact of climate change is important for ecosystem conservation and plant recovery, especially in climate sensitive regions. Various studies suggested that the KSppen classification is an effective method to depict climate change. However, these studies were restricted to large scales or of limited accuracy due to uncertainties in climate model projections. In addition, the impact of elevation on the shift of climate zones, as compared with other factors, is less emphasized. To address these issues we compiled the KSppen Climate Classification （period 1961-2olo） for the study area, Sichuan Province, China. The spatial resolution was selected as x km x x km. Sichuan Province may be characterized by 3 main climate classes and 1o subtypes. The east-west gradient of the climatic regimes in Siehuan is represented by the main climate classes, warm temperate climates （C）, snow climates （D） and polar climates （E）, at which the most abundant class is C. The most abundant subtype is snow climate with dry winter and cool summer （Dwe）. Shifts in K/Sppen climate classes reflect the observed trend of increasing temperature. Finally, the elevation showed an obvious impact on the distribution and the change of climate classes in Siehuan Province. The shift of areas covered by KSppen climate classes increases with elevation.

关键词： Koppen Climate Classification Climatechange Elevation Sichuan

Signed Zero-Divisor Graphs Over Commutative Rings

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Communications in Mathematics and Statistics 2024年第3期12卷 463-477页

作者： lu lu Lihua feng Weijun liu School of Mathematics and Statistics HNP-LAMACentral South UniversityChangsha 410083HunanPeople’s Republic of China

In this paper,we define signed zero-divisor graphs over commutative rings and investigate the interplay between the algebraic properties of the rings and the combinatorial properties of their corresponding signed zero-divisor *** investigate the structure of signed zero-divisor graphs,the relation between ideals and signed zero-divisor graphs,and the adjacency matrices and the spectra of signed zero-divisor graphs.

关键词： Ring Ideal Signed graph Adjacency matrix

A holistic approach to aligning geospatial data with multidimensional similarity measuring

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International Journal of Digital Earth 2018年第8期11卷 845-862页

作者： Li yu Peiyuan Qiu Xiliang liu feng lu Bo Wan State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China National Science Library Chinese Academy of SciencesBeijingPeople’s Republic of China Fujian Collaborative Innovation Center for Big Data Applications in Governments FuzhouPeople’s Republic of China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application NanjingPeople’s Republic of China Faculty of Information Engineering China University of GeosciencesWuhanPeople’s Republic of China

Semantically aligning the heterogeneous geospatial datasets(GDs)produced by different organizations demands efficient similarity matching ***,the strategies employed to align the schema(concept and property)and instances are usually not reusable,and the effects of unbalanced information tend to be neglected in GD *** solve this problem,a holistic approach is presented in this paper to integrally align the geospatial entities(concepts,properties and instances)***,lexical,structural and extensional similarity metrics are designed and automatically aggregated by means of approval *** presented approach is validated with real geographical semantic webs,Geonames and *** with the well-known extensional-based aligning system,the presented approach not only considers more information involved in GD alignment,but also avoids the artificial parameter setting in metric *** reduces the dependency on specific information,and makes the alignment more robust under the unbalanced distribution of various information.

关键词： Geospatial data data alignment similarity matching semantic web

甲壳类水产品致敏原及特异性免疫制品的研究进展

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食品工业科技 2025年第1期46卷 403-412页

作者：李梦思夏菲刘庆梅黄苏杰卢艺彬桓霏刘萌刘翼翔刘光明漳州职业技术学院食品工程学院福建漳州363000 集美大学海洋食品与生物工程学院福建省海洋功能食品工程技术研究中心厦门市海洋功能食品重点实验室福建厦门361021 厦门海洋职业技术学院福建厦门361100

甲壳类水产品是我国常见的致敏食物之一,除了规避致敏食物的摄入,目前仍无有效的根治方法。因此,致敏原的性质分析及防控技术方法的研究至关重要。本文针对甲壳类水产品致敏原,介绍了致敏原的免疫学特性与分子结构,归纳了致敏原的抗原表... 详细信息

甲壳类水产品是我国常见的致敏食物之一,除了规避致敏食物的摄入,目前仍无有效的根治方法。因此,致敏原的性质分析及防控技术方法的研究至关重要。本文针对甲壳类水产品致敏原,介绍了致敏原的免疫学特性与分子结构,归纳了致敏原的抗原表位,探讨了应用于致敏原特异性治疗的免疫制品,比较了不同免疫制品的作用机理及优缺点,可为研发水产品过敏的防控技术方法提供参考。

关键词：甲壳类水产品致敏原分子结构抗原表位特异性免疫制品

Florigen trafficking integrates photoperiod and temperature signals in Arabidopsis^FA

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Journal of Integrative Plant Biology 2020年第9期62卷 1385-1398页

作者： lu liu yu Zhang Hao yu School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China Department of Biological Sciences National University of SingaporeSingapore 117543Singapore Temasek Life Sciences Laboratory National University of SingaporeSingapore 117604Singapore

The transition to flowering is the most dra-matic phase change in flowering plants and is crucial for reproductive success. A complex regulatory network in plants has evolved to perceive and integrate the endog-enous and environmental signals. These signals perceived, including day length and temperature, converge to regu-late FLOWERING LOCUS T (FT), which encodes a mobile stimulus required for floral induction in Arabidopsis. Despite the discovery of modulation of FT messenger RNA (mRNA) expression by ambient temperature, whether the trafficking of FT protein is controlled in response to changes in growth temperature is so far unknown. Here, we show that FT transport from companion cells to sieve elements is controlled in a temperature-dependent manner. This process is mediated by multiple C2 domain and transmembrane region proteins (MCTPs) and a soluble N-ethylmaleimide-sensitive factor protein attach-ment protein receptor (SNARE). Our findings suggest that ambient temperatures regulate both FT mRNA expression and FT protein trafficking to prevent precocious flowering at low temperatures and ensure plant reproductive suc-cess under favorable environmental conditions.

关键词： integrate ambient traffic