检索结果-南通市图书馆

Comparative study on wheel-rail dynamic interactions of side-frame cross-bracing bogie and sub-frame radial bogie

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Transportation 2013年第1期21卷 1-8页

作者： chunlei yang Fu Li Yunhua Huang Kaiyun Wang Baiqian He School of Mechanical Engineering Southwest Jiaotong University Department of Product Development CSR Meishan Company Limited State Key Laboratory of Traction Power Southwest Jiaotong University

Improving freight axle load is the most effective method to improve railway freight capability; based on the imported technologies of railway freight bogie, the 27 t axle load side-frame cross-bracing bogie and sub-frame radial bogie are developed in China. In order to analyze and compare dynamic interactions of the two newly developed heavy-haul freight bogies, we establish a vehi- cle-track coupling dynamic model and use numerical calculation methods for computer simulation. The dynamic performances of the two bogies are simulated separately at various conditions. The results show that at the dipped joint and straight line running conditions, the wheel-rail dynamic interactions of both bogies are basically the same, but at the curve negotiation condition, the wear and the lateral force of the side-frame cross-bracing bogie are much higher than that of the sub-frame radial bogie, and the advantages become more obvious when the curve radius is smaller. The results also indicate that the sub- frame radial bogie has better low-wheel-rail interaction characteristics.

关键词： Heavy haul Side-frame cross-bracing bogie .Sub-frame radial bogie . Wheel-rail dynamic interaction

Pyrolysis of single carbon sources in SBA-15: A recyclable solid phase synthesis to obtain uniform carbon dots with tunable luminescence

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第2期34卷 458-462页

作者： Xiaoqing Niu Weijie Zheng Tianbing Song Zunhui Huang chunlei yang Liming Zhang Wei Li Huanming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Most of carbon dots(CDs) are synthesized in solutions, but the extensive use of solvents produces too much waste, needs complex purification and results in low yield. Particularly for the popular hydrothermal/solvothermal syntheses, safety issues hinder the large-scale production of CDs. Solid phase synthesis in air seems perfect to solve the above problems once for all, but nanoparticle growth in solid phase is always difficult to control. Here we suggest a new method to synthesize CDs in SBA-15 template, just by heating single carbon sources in air. Employing single carbon sources is important, which ensures both homogeneity of the nucleation and uniformity of the nanoparticle growth. The pores confinement of SBA-15 guarantees the uniform sizes of CDs, while the catalytic effect of SBA-15 accelerates the carbonization process of precursors. The products are easily extracted from the template by ethanol, and then the template can be recycled for the next synthesis after calcination. Various CDs are synthesized in this way by using different carbon sources and SBA-15 templates with different pore diameters, respectively. The results show that, the fluorescence properties of these CDs are determined by their composition and surface states, but not the particle sizes. This work opens a new avenue to synthesize uniform CDs in solid phase with high yield, low cost and tunable luminescence.

关键词： Carbon dots Solid phase synthesis SBA-15 Luminescence Uniformity

Polyimide separators for rechargeable batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第7期30卷 170-197页

作者： Ziheng Lu Fan Sui Yue-E Miao Guohua Liu Cheng Li Wei Dong Jiang Cui Tianxi Liu Junxiong Wu chunlei yang Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055GuangdongChina College of Materials Science and Engineering Donghua UniversityShanghai 201620China Department of Materials Science and Engineering Clemson UniversityClemsonSC 29634USA Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina

Separators are indispensable components of modern electrochemical energy storage devices such as lithium-ion batteries(LIBs).They perform the critical function of physically separating the electrodes to prevent short-circuits while permitting the ions to pass *** conventional separators using polypropylene(PP) and polyethylene(PE) are prone to shrinkage and melting at relatively high temperatures(150℃ or above) causing short circuits and thermal runaway,separators made of thermally stable polyimides(PIs) are electrochemically stable and resistant to high temperatures,and possess good mechanical strength-making them a promising solution to the safety concerns of *** this review,the research progress on PI separators for use in LIBs is summarized with a special focus on molecular design and microstructural *** view of the significant progress in advanced chemistries beyond LIBs,recent advances in PI-based membranes for applications in lithium-sulfur,lithium-metal,and solid-state batteries are also ***,practical issues are also discussed along with their prospects.

关键词： Polyimide Lithium-ion batteries Separators Solid-state batteries Molecular design

Rumen microbiota-host transcriptome interaction mediates the protective effects of trans-10,cis-12 CLA on facilitating weaning transition of lambs

在线全文

学校读者我要写书评

暂无评论

Animal Nutrition 2023年第1期12卷 345-359页

作者： chunlei yang Xiangfei Deng Peter Lund Haixia Liu Xingwang Ding Zhengwei Fu Naifeng Zhang Jinjun Li Lifeng Dong College of Biotechnology and Bioengineering Zhejiang University of TechnologyHangzhou310014China Department of Animal Science Aarhus UniversityAU FoulumDK-8830TjeleDenmark Jiangsu Agri-animal Husbandry Vocational College Taizhou225300China Institute of Feed Research Chinese Academy of Agricultural Sciences/Sino-US Joint Lab on Nutrition and Metabolism of RuminantBeijing100081China Institute of Food Sciences Zhejiang Academy of Agricultural SciencesHangzhou310021China

Developing alternatives to antibiotics for prevention of gastrointestinal dysbiosis in early-weaning farmed animals is urgently *** study was to explore the potential effects of trans-10,cis-12 conjugated linoleic acid(CLA)on maintaining ruminal homeostasis of young ruminants during the weaning transition *** neonatal lambs were selected(6 lambs per group)and euthanized for rumen microbial and epithelial *** lambs were weaned at 28 d and experienced the following 5 treatments:euthanized on d 28 as the pre-weaning control(CON0),fed starter feed for 5(CON5)or 21(CON21)d,fed starter feed with 1%of CLA supplemented for 5(CLA5)or 21(CLA21)*** showed that the average daily weight gain and dry matter intake were significantly higher in CLA5 than CON5 *** compared with the CON5 and CON21 group,the relative abundances of volatile fatty acid(VFA)producing bacteria including Bacteroides,Treponema,Parabacteroides and Anaerovibrio,as well as the concentrations of acetate,butyrate and total VFA were significantly increased in CLA5 and CLA21 group,*** microbial profiling and epithelial transcriptome results showed that 7 downregulated inflammatory signaling-related host genes IL2RA,CXCL9,CD4,CCR4,LTB,SPP1,and BCL2A1 with CLA supplementation were significantly negatively correlated with both VFA concentration and VFA producing bacteria,while 3(GPX2,SLC27A2 and ALDH3A1)and 2(GSTM3 and GSTA1)upregulated metabolism-related genes,significantly positively correlated with either VFA concentration or VFA producing bacteria,*** confirm the effects of CLA on epithelial signal transduction,in vitro experiment was further conducted by treating rumen epithelial cells without or with IL-17A+TNF-αfor 12 h after pretreatment of 100μM CLA or not(6 replicates per treatment).The results demonstrated the anti-inflammatory effect of CLA via suppressing the protein expression of NF-кB p-p65/p65 with the activation of peroxisome prol

关键词： Trans-10,cis-12 conjugated linoleic acid Rumen microbiota Epithelial transcriptome Peroxisome proliferator-activated receptor gamma Weaning stress

Multifunctional Flexible Vanadium Dioxide Films

在线全文

学校读者我要写书评

暂无评论

Accounts of Materials Research 2021年第9期2卷 714-725页

作者： Tianci Chang Ying Zhu Cuicui Cao chunlei yang Hongjie Luo Ping Jin Xun Cao Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055 GuangdongChina Shenzhen High Technology Investment Group Co. Ltd.Shenzhen 518040 GuangdongChina Department of Materials Engineering The University of British ColumbiaVancouverBC V6T 1Z4Canada Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055 GuangdongChina State Key Laboratory of High-Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

CONSPECTUS:As a typical phase transition material,vanadium dioxide(VO_(2))has attracted much attention due to its amazing metal−insulator transition(MIT)at the critical temperature of 68°C,which could be driven by multiple stimuli,including electricity,thermal irradiation,THz waves,strain,*** the MIT process,VO_(2)exhibits significant changes in its structure from monoclinic structure at low temperature to rutile structure at high temperature,accompanied by significant modulation of physical properties,such as the infrared transmittance from high to low and a resistivity drop over 5 *** on these features,VO_(2)has functioned as thermochromic coatings,sensors,switches,electronic devices,actuators,***,the vanadium element possesses multiple valent states and can produce complicated thermodynamics of vanadium *** fabrication of tetravalence VO_(2)with desirable phase-transition features usually requires rigorous fabrication conditions with a precisely controlled atmosphere for stoichiometric components and high temperatures for good *** these circumstances,it is difficult to directly fabricate crystalline VO_(2)films on flexible polymer substrates because most of them could not stand such high temperatures(usually>400°C),which will lead to the loss of the substrate ***,the featured phase transition of VO_(2)makes it a promising candidate for future flexible devices,while VO_(2)owns great potential as flexible optical coatings,flexible sensors,flexible electronics,***,research on flexible VO_(2)films is necessary and could largely pave the way to the application field of VO_(2)*** this Account,we start with a brief introduction to phase transition properties of VO_(2)to reveal the intrinsic advantages as key materials in flexible ***,multifunctional devices based on flexible VO_(2)films with different forms and characteristics are presented,including(1)flexible VO_(2)-film-based ther

关键词： vanadium dioxide thermodynamics

Influence of Curve Geometric Parameters on Curving Performance of Sub-frame Radial Bogie

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mechanical Engineering Science 2021年第1期3卷 50-56页

作者： chunlei yang Yunhua HUANG Junjun DING School of Information Engineering Hubei Minzu UniversityEnshi 445000HubeiChina School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031SichuanChina

Based on the theory of vehicle-track coupling dynamics,the coupling dynamic model of the freight car mounted with the sub-frame bogies and the numerical model of curved track were established,utilizing the fast numerical integration method,the curving performance of the vehicle was simulated to study the influence of the curve geometric parameters such as curve radius,transition curve length and superelevation of outer rail on the wheel-rail dynamic *** simulation results indicate that:(1)Increasing the curve radius can decrease the wheel-rail wear,but the effect will weaken while the curve radius is greater than 800m.(2)If the transition curve length is less than 30m,vibrations will appear at the transition-circle connecting point,and the smaller the transition length,the bigger the vibrations,the worse the wheel-rail wear,but when the length is bigger than 50m,its further variation has very little effect on wheel-rail wear.(3)The superelevation of outer rail can affect the distribution and difference of the inner and outer wheel-rail forces,and too large deficient or excessive superelevation will worsen the wheel-rail wear ***,an appropriate deficient superelevation of outer rail(e.g.<20mm)is helpful to reduce the wheel-rail wear,which is consistent with the engineering practice of settling a certain deficient superelevation value.

关键词： heavy-haul freight car sub-frame radial bogie curve geometric parameters wheel-rail wear

Speed-up Multi-modal Near Duplicate Image Detection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Applied Sciences 2013年第1期3卷 16-21页

作者： chunlei yang Jinye Peng Jianping Fan 1CSIRO Sustainable Ecosystems Carmody Road St. Lucia Queensland Australia 2CSIRO Sustainable Ecosystems Highett Australia CSIRO Sustainable Ecosystems Highett Australia

Near-duplicate image detection is a necessary operation to refine image search results for efficient user exploration. The existences of large amounts of near duplicates require fast and accurate automatic near-duplicate detection methods. We have designed a coarse-to-fine near duplicate detection framework to speed-up the process and a multi-modal integra-tion scheme for accurate detection. The duplicate pairs are detected with both global feature (partition based color his-togram) and local feature (CPAM and SIFT Bag-of-Word model). The experiment results on large scale data set proved the effectiveness of the proposed design.

关键词： Near-Duplicate Detection Coarse-To-Fine Framework Multi-Modal Feature Integration

Advances in CIGS thin film solar cells with emphasis on the alkali element post-deposition treatment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Reports(Energy) 2023年第3期3卷 24-40页

作者： Chenchen Zhao Shen Yu Wei Tang Xinye Yuan Hongfei Zhou Tongqing Qi Xue Zheng De Ning Ming Ma Junyi Zhu Jie Zhang chunlei yang Weimin Li Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 18055PR China Department of Nano Science and Technology Institute University of Science and Technology of ChinaSuzhou 215123PR China University of Chinese Academy of Sciences Beijing 100049PR China Department of Physics The Chinese University of Hong KongShatin 999077PR China

In the past tens of years,the power conversion efficiency of Cu(In,Ga)Se2(CIGS)has continuously improved and been one of the fastest growing photovoltaic technologies that can also help us achieve the goal of carbon emissions *** several key advances,the alkali element post-deposition treatment(AlK PDT)is regarded as the most important finding in the last 10 years,which has led to the improvement of CIGS solar cell efficiency from 20.4%to 23.35%.A profound understanding of the influence of alkali element on the chemical and electrical properties of the CIGS absorber along with the underlying mechanisms is of great *** this review,we summarize the strategies of the alkali element doping in CIGS solar cell,the problems to be noted in the PDT process,the effects on the CdS buffer layer,the effects of different alkali elements on the structure and morphology of the CIGS absorber layer,and retrospect the progress in the CIGS solar cell with emphasis on the alkali element post deposition treatment.

关键词： CIGS solar cells Post-deposition treatment Alkali element Efficiency Absorber

Palaeoecological and palaeoenvironmental significance of someimportant spores and micro-algae in Quaternary deposits

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2013年第20期58卷 3125-3139页

作者： TANG LingYu MAO LiMi Lü XinMiao MA QingFeng ZHOU ZhongZe yang chunlei KONG ZhaoChen BATTEN David J State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences University of Chinese Academy of Sciences School of Resources and Environmental Engineering Anhui University Institute of Botany Chinese Academy of Sciences School of Earth Atmospheric and Environmental Sciences University of Manchester

Spores of ferns and allied plants, and micro-algae frequently occur in abundance in Quaternary deposits, but their palaeoenvironmental significance is seldom evaluated. This paper presents morphological descriptions of spores of Selaginella sinensis (Desv.) Spring, 1843 (Selaginellaceae) and Ceratopteris cf. thalictroides (L.) Brongniart, 1821 (Parkeriaceae) and the algae Pediastrum boryanum (Turpin) Meneghini, 1840, P. simplex Meyen, 1829, P. integrum N geli, 1849 (all Hydrodictyaceae), Spiniferites Mantell, 1850, emend. Sarjeant, 1970 (Spiniferitaceae) and Concentricystes Rossignal, 1962, emend. Jiabo, 1978 (systematic position unclear), and discusses their occurrence in mostly Quaternary sedimentary successions. All are closely associated with aquatic habitats. Extant Selaginella sinensis often colonizes fairly wet hillsides and gaps between rocks, and shady sides of ravines and slopes; it is also found within thickets of trees and shrubs (boscages) and in forests with calcareous soils. Ceratopteris thalictroides, Pediastrum and Concentricystes inhabit freshwater lakes and both natural and artificial wetlands, such as paddy fields and ditches. Spiniferites is a salt-water genus and usually associated with the marine realm. Fossil and subfossil representatives of all of these taxa can be useful proxies of biodiversity and, therefore, also important for determining environmental conditions during the Quaternary period.

关键词：第四纪沉积物古环境意义微型藻类孢子形态古生态蕨类植物石灰性土壤生物多样性

同方期刊数据库