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Effect of annealing treatment on hydrogen storage properties of La-Ti-Mg-Ni-based alloy

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Journal of Rare Earths 2012年第5期30卷 450-455页

作者：蒋卫卿莫晓华韦银燕周正诚郭进 Key Laboratory of National Education Ministry for Nonferrous Metals and Materials Processing technology College of Physics Science and TechnologyGuangxi University College of Physics and Electronic Engineering Guangxi University for Nationalities International centre for Materials Physics Chinese Academy of Sciences

The present study dealt with investigations on the effects of annealing on the hydrogen storage properties of La 1.6 Ti 0.4 MgNi 9 *** experimental alloys were prepared by magnetic levitation melting followed by annealing *** La 1.6 Ti 0.4 MgNi 9 alloys,LaNi 5,LaNi 3 and LaMg 2 Ni 9 were the main phases,Ti 2 Ni phase appeared at 900℃.Annealing not only enhanced the maximum and effective hydrogen storage capacity,improved the hydrogen absorption/desorption kinetics,but also increased the discharge *** cyclic stability had been improved markedly by annealing,e.g.,when the discharge capacity reduced to 60% of maximum discharge capacity,the charge/discharge cycles increased from 66（as-cast） to 89（annealed at 800℃） and 127 times（annealed at 900℃）.La 1.6 Ti 0.4 MgNi 9 alloy annealed at 900℃ exhibited better electrochemical properties compared to the other two alloy electrodes.

关键词： La-Ti-Mg-Ni-based hydrogen storage property annealing electrochemical performance rare earths

Estimation of suspended sediment concentrations using Pulse-coherent Acoustic Doppler Profiler (PCADP)

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Chinese Journal of Oceanology and Limnology 2009年第2期27卷 260-265页

作者：柏秀芳李思忍龚德俊徐永平姜静波 Institute of Oceanology Chinese Academy of SciencesR&D Centre of Ocean Environmental Engineering and Technology Qingdao Feiyang Vocational & Technical College

The objective of the study is to investigate the suitability of using Pulse-coherent Acoustic Doppler Profiler (PCADP) to estimate suspended sediment concentration (SSC). The acoustic backscatter intensity was corrected for spreading and absorption loss, then calibrated with OBS and finally converted to SSC. The results show that there is a good correlation between SSC and backscatter intensity with R value of 0.74. The mean relative error is 22.4%. Then the time span of little particle size variation was also analyzed to exclude the influence of size variation. The correlation coefficient increased to 0.81 and the error decreased to 18.9%. Our results suggest that the PCADP can meet the requirement of other professional instruments to estimate SSC with the errors between 20% and 50%, and can satisfy the need of dynamics study of suspended particles.

关键词： Doppler Profiler (PCADP) suspended sediment concentration (SSC) acoustic backscatterintensity

Spatial targeting evaluation of energy and environmental performance of waste-to-energy processing

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 731-744页

作者： Petar S.Varbanov Timothy G.Walmsley Yee V.Fan Jiri J.Klemes Simon J.Perry Sustainable Process Integration Laboratory NETME CentreFaculty of Mechanical EngineeringBmo University of Technology61669 Bmo Czech Republic centre for Process Integration School of Chemical Engineering and Analytical ScienceThe University of ManchesterManchester M I 3ALUK

Waste-to-energy supply chains are important potential contributors to minimising the environmental impacts of municipal solid waste by reducing the amounts of waste sent to landfill, as well as the fossil fuel consumption and environmental footprints. Accounting for the spatial and transport properties of the waste-to-energy supply chains is crucial for understanding the problem and improving the supply chain designs. The most significant challenge is the distributed nature of the waste generation and the household energy demands. The current work proposes concepts and a procedure for targeting the size of the municipal solid waste collection zone as the first step in the waste-to-energy supply chains synthesis. The formulated concepts and the provided case study reveal trends of reducing the net greenhouse gas savings and energy recovery by increasing the collection zone size. Population density has a positive correlation with the greenhouse gas saving and energy recovery performance. For smaller zone size the energy recovery from waste approaches and in some cases may surpass the energy spent on waste transportation. The energy recovery and greenhouse gas savings remain significant even for collection zones as large as 200 km2. The obtained trends are discussed and key directions for future work are proposed.

关键词： waste-to-energy supply chain optimisation GHG savings energy recovery ratio

Broadband infrared imaging governed by guidedmode resonance in dielectric metasurfaces

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Light(Science & Applications) 2024年第11期13卷 2599-2610页

作者： Ze Zheng Daria Smirnova Gabriel Sanderson Ying Cuifeng Demosthenes C.Koutsogeorgis Lujun Huang Zixi Liu Rupert Oulton Arman Yousefi Andrey E.Miroshnichenko Dragomir N.Neshev Mary O’Neill Mohsen Rahmani Lei Xu advanced Optics and Photonics Laboratory Department of EngineeringSchool of Science&TechnologyNottingham Trent UniversityNottingham NG118NSUK ARC centre of Excellence for Transformative Meta-Optical Systems(TMOS) Research School of PhysicsThe Australian National UniversityCanberraACT 2601Australia School of Science&technology Nottingham Trent UniversityNottingham NG118NSUK School of Physics and Electronic Science East China Normal UniversityShanghai 200241China School of Physics Nankai UniversityTianjin 300071China Department of Physics Imperial College LondonLondon SW72BWUK School of Engineering and technology University of New South WalesCanberraACT 2600Australia

Nonlinear metasurfaces have experienced rapid growth recently due to their potential in various applications,including infrared imaging and ***,due to the low conversion efficiencies of metasurfaces,several strategies have been adopted to enhance their performances,including employing resonances at signal or nonlinear emission *** strategy results in a narrow operational band of the nonlinear metasurfaces,which has bottlenecked many applications,including nonlinear holography,image encoding,and nonlinear ***,we overcome this issue by introducing a new nonlinear imaging platform utilizing a pump beam to enhance signal conversion through four-wave mixing(FWM),whereby the metasurface is resonant at the pump wavelength rather than the signal or nonlinear *** a result,we demonstrate broadband nonlinear imaging for arbitrary objects using metasurfaces.A silicon disk-on-slab metasurface is introduced with an excitable guided-mode resonance at the pump *** enabled direct conversion of a broad IR image ranging from>1000 to 4000 nm into ***,adopting FWM substantially reduces the dependence on high-power signal inputs or resonant features at the signal beam of nonlinear imaging by utilizing the quadratic relationship between the pump beam intensity and the signal conversion *** results,therefore,unlock the potential for broadband infrared imaging capabilities with metasurfaces,making a promising advancement for next-generation all-optical infrared imaging techniques with chip-scale photonic devices.

关键词： utilizing resonant governed

Overview of current design and analysis of potential theories for automated fibre placement mechanisms

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Chinese Journal of Aeronautics 2022年第4期35卷 1-13页

作者： Wuxiang ZHANG Fei LIU Tao JIANG Minghui YI Weiqiang CHEN Xilun DING School of Mechanical Engineering and Automation Beihang University37 Xueyucm RoadBeijing 100191China Ningbo Institute of technology Beihang UniversityNingbo 315832China Beijing Weixing manufacturing Plant Co. LtdBeijing 100191China

Automated fibre placement(AFP) systems have successfully intensified the demand for high-quality composite component manufacturing in both the military and civilian fields. One of the main elements of these systems is the AFP mechanism for accomplishing individual fibre delivery,clamp/cut/restart(CCR) and the consolidation process, and it consists of several functional submechanisms presenting strong coupling relationships and motion sequences. This review aims to summarize the development of AFP mechanisms and the associated research achievements and provide insight into the research challenges in promoting innovative design in such mechanisms. The systematic development of AFP systems is reviewed in detail, and subsequently, engineering tendency and the general principle of AFP mechanisms are introduced. Focusing on the mechanism design of AFP sub-mechanisms, including the creel assembly CCR and compaction mechanisms,the mechanical schemes as well as the AFP process parameter control are discussed. To improve system reliability and fully optimise AFP mechanisms, the essential theoretical foundation for AFP mechanisms are provided. It is believed that this attempt will help to change the design and optimisation of similar complete mechanisms. Based on the reviewed research, overall remarks and perspectives are presented to serve as a guide for exploring the possibility of novel easy-to-use and cost-effective integrated AFP applications.

关键词： Automated fibre placement systems Sub-mechanisms Structure design Layup performance Theoretical foundation

Panel positioning error and support mechanism for a 30-m THz radio telescope

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research in Astronomy and Astrophysics 2011年第6期11卷 725-736页

作者： De-Hua Yang Daniel Okoh Guo-Hua Zhou Ai-Hua Li Guo-Ping Jing-Quan Cheng National Astronomical Observatories /Nanjing Institute of Astronomical Optics ＆ technology Chinese Academy of SciencesNanjing 210042China Key Laboratory of Astronomical Optics ＆ technology Nanjing Institute of Astronomical Optics ＆ TechnologyChinese Academy of SciencesNanjing 210042China centre for Basic Space Science National Space Research and Development AgencyUniversity of NigeriaNsukka 410002Nigeria National Radio Astronomy Observatory CharlottesvilleVA 22903USA

A 30-m TeraHertz（THz） radio telescope is proposed to operate at 200 μm with an active primary *** paper presents sensitivity analysis of active surface panel positioning errors with optical performance in terms of the Strehl *** on Ruze＇s surface error theory and using a Monte Carlo simulation,the effects of six rigid panel positioning errors,such as piston,tip,tilt,radial,azimuthal and twist displacements,were directly *** optical performance of the telescope was then evaluated using the standard Strehl *** graphically illustrated the various panel error effects by presenting simulations of complete ensembles of full reflector surface errors for the six different rigid panel positioning *** of the panel error sensitivity analysis revealed that the piston error and tilt/tip errors are dominant while the other rigid errors are much less ***,as indicated by the results,we conceived of an alternative Master-Slave Concept-based（MSC-based） active surface by implementating a special Series-Parallel Concept-based（SPC-based） hexapod as the active panel support mechanism.A new 30-m active reflector based on the two concepts was demonstrated to achieve correction for all the six rigid panel positioning errors in an economically feasible way.

关键词： telescopes-methods:data analysis-methods:statistical-techniques:miscellaneous

Distribution Patterns of the Snail Intermediate Host of Schistosoma japonicum-China,2015−2019

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China CDC weekly 2021年第5期3卷 81-84页

作者： Lijuan Zhang Shan Lv Chunli Cao Jing Xu Shizhu Li National Institute of Parasitic Diseases Chinese Center for Disease Control and PreventionChinese Center for Tropical Diseases ResearchWHO Collaborating Centre for Tropical DiseasesNational Center for International Research on Tropical DiseasesMinistry of Science and TechnologyKey Laboratory of Parasite and Vector BiologyMinistry of HealthShanghaiChina

What is already known about this topic?The endemic status of schistosomiasis appeared to continuously decrease in China from 2015 to *** snail species Oncomelania hupensis is the only intermediate host involved in the transmission of Schistosoma japonicum,and this snail’s geographic distribution is strictly consistent with that of *** is added by this report?The snail’s habitats did not decrease significantly in China from 2015 to 2019,and some habitats have been newly detected or recurrent in some *** habitats among nine counties in Hunan and Jiangxi covered nearly half of the areas with *** are the implications for public health practice?Considering the situation of snail distribution,strategies and measures on snail control should focus on key *** addition,study of the origin and causes of the newly-detected snail habitats and recurrent areas with snails needs to be strengthened,and comprehensive measures should be taken to prevent the spread of snails.

关键词： Schistosoma schistosomiasis continuously

Induced pluripotent stem cells: Mechanisms, achievements and perspectives in farm animals

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World Journal of Stem Cells 2015年第2期7卷 315-328页

作者： Dharmendra Kumar Thirumala R Talluri Taruna Anand Wilfried A Kues Institute of Farm Animal Genetics Friedrich-Loeffler-Institute Animal Physiology and Reproduction Division Central Institute for Research on Buffaloes National research centre on Equines

Pluripotent stem cells are unspecialized cells withunlimited self-renewal, and they can be triggered to differentiate into desired specialized cell types. These features provide the basis for an unlimited cell source for innovative cell therapies. Pluripotent cells also allow to study developmental pathways, and to employ them or their differentiated cell derivatives in pharmaceutical testing and biotechnological applications. Via blastocyst complementation, pluripotent cells are a favoured tool for the generation of genetically modified mice. The recently established technology to generate an induced pluripotency status by ectopic co-expression of the transcription factors Oct4, Sox2, Klf4 and c-Myc allows to extending these applications to farm animal species, for which the derivation of genuine embryonic stem cells was not successful so far. Most induced pluripotent stem(i PS) cells are generated by retroviral or lentiviral transduction of reprogramming factors. Multiple viral integrations into the genome may cause insertional mutagenesis and may increase the risk of tumour formation. Non-integration methods have been reported to overcome the safety concerns associated with retro and lentiviral-derived i PS cells, such as transient expression of the reprogramming factors using episomal plasmids, and direct delivery of reprogramming m RNAs or proteins. In this review, we focus on the mechanisms of cellular reprogramming and current methods used to induce pluripotency. We also highlight problems associated with the generation of i PS cells. An increased understanding of the fundamental mechanisms underlying pluripotency and refining the methodology of i PS cell generation will have a profound impact on future development and application in regenerative medicine and reproductive biotechnology of farm animals.

关键词： Reprogramming Large animal models Stemness Chimera Germline transmission Inducedpluripotent stem cells Gene delivery

Comparative studies on as-cast microstructures and mechanical properties between Mg-3Ce-1.2Mn-0.9Sc and Mg-3Ce-1.2Mn-1Zn magnesium alloys

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Transactions of Nonferrous Metals Society of China 2012年第1期22卷 53-59页

作者： YANG Ming-bo PAN Fu-sheng Materials Science and Engineering College Chongqing University of TechnologyChongqing 400054China Key Laboratory ofAutomobile Components manufacturing and Testing technology of Ministry of Education Chongqing University of TechnologyChongqing 400054China National Engineering research Center for Magnesium Alloys Chongqing UniversityChongqing 400030China

The as-cast microstructures and mechanical properties of Mg-3Ce-1.2Mn-0.9Sc and Mg-3Ce-1.2Mn-1Zn magnesium alloys were investigated and compared. The results indicate that the Sc-containing alloy mainly consists of α-Mg, Mg12Ce and Mn2Sc phases, and the Zn-containing alloy is mainly composed of α-Mg and Mg12Ce phases. The morphologies of the Mg12Ce phases in the two as-cast alloys are different. The Mg12Ce phases in the Sc- and Zn-containing alloys mainly exhibit particle-like shapes and continuous and/or quasti-continuous nets, respectively. Furthermore, the grains of the Sc-containing alloy are finer than those of the Zn-containing alloy. In addition, the Sc- and Zn-containing alloys have similar as-cast tensile properties at room temperature and 300 °C. However, the Sc-containing alloy exhibits higher creep-resistant properties at 300 °C and 30 MPa for 100 h than the Zn-containing alloy.

关键词： magnesium alloy Mg-Ce-Mn based alloys Sc Zn Mg12Ce phase