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履带车辆摩擦片使用性能影响因素分析

兵器材料科学与工程 2005年第3期28卷 30-33页

作者：牛雯霞刘晓强韩文政装甲兵工程学院材料科学与工程系北京100072 总装驻617厂军代室内蒙古包头014032

定性地讨论了履带车辆行星变速箱中载荷、润滑和温度对摩擦片使用性能的影响。油压特性决定了换档时摩擦片的滑摩时间长短,在不增大滑摩功的前提下,可以适当降低操纵油压;优化润滑结构可均匀分配润滑油,合成油是适宜履带车辆离合器和制... 详细信息

定性地讨论了履带车辆行星变速箱中载荷、润滑和温度对摩擦片使用性能的影响。油压特性决定了换档时摩擦片的滑摩时间长短,在不增大滑摩功的前提下,可以适当降低操纵油压;优化润滑结构可均匀分配润滑油,合成油是适宜履带车辆离合器和制动器的油品,粘度的大小是选用润滑油的重要准则;摩擦片正常工作的条件之一是其内部温度与工作环境温度差保持动态平衡。

关键词：履带车辆变速箱摩擦片使用性能影响因素

市场竞争中具溢出效应共同供应商质量投资策略

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管理工程学报 2017年第2期31卷 222-232页

作者：牛文举夏晶汤伟沈厚才南京大学管理科学与工程系江苏南京210093

产品质量是一个重要竞争维度,制造商有动机对供应商进行质量投资来提高产品质量水平。但一个供应商有可能与多个制造商存在合作,导致制造商的质量投资产生溢出从而提高其竞争对手的产品质量水平。本文研究存在质量溢出效应的情况下制造... 详细信息

产品质量是一个重要竞争维度,制造商有动机对供应商进行质量投资来提高产品质量水平。但一个供应商有可能与多个制造商存在合作,导致制造商的质量投资产生溢出从而提高其竞争对手的产品质量水平。本文研究存在质量溢出效应的情况下制造商是否应对供应商进行质量投资的问题。考虑由一个供应商和两个竞争性制造商组成的供应链,分别构建了无质量投资、单一制造商进行质量投资和两个制造商进行质量投资三种情形下的决策模型,刻画了溢出系数对均衡结果的影响。研究表明:供应商更希望两个制造商在相对较弱的溢出效应下共同进行质量投资。对制造商而言,无论溢出效应如何或者竞争对手投资与否,一个制造商的最优策略是对供应商进行质量投资。

关键词：供应链质量竞争价格竞争质量投资溢出效应

Porous Organic Cage‑Based Quasi‑Solid‑State Electrolyte with Cavity‑Induced Anion‑Trapping Effect for Long‑Life Lithium Metal Batteries

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Nano-Micro Letters 2025年第2期17卷 376-386页

作者： Wei-Min Qin Zhongliang Li wen‑xia Su Jia‑Min Hu Hanqin Zou Zhixuan Wu Zhiqin Ruan Yue‑Peng Cai Kang Li Qifeng Zheng School of Chemistry South China Normal UniversityGuangzhou 510006People’s Republic of China Key Laboratory of Functional Metal‑Organic Compounds of Hunan Province College of Chemistry and Material ScienceHengyang Normal UniversityHengyang 421008People’s Republic of China Guangzhou Key Laboratory of Energy Conversion and Energy Storage Materials Guangzhou 510006People’s Republic of China

Porous organic cages(POCs)with permanent porosity and excellent host–guest property hold great potentials in regulating ion transport behavior,yet their feasibility as solid-state electrolytes has never been testified in a practical ***,we design and fabricate a quasi-solid-state electrolyte(QSSE)based on a POC to enable the stable operation of Li-metal batteries(LMBs).Benefiting from the ordered channels and cavity-induced anion-trapping effect of POC,the resulting POC-based QSSE exhibits a high Li+transference number of 0.67 and a high ionic conductivity of 1.25×10^(−4) S cm^(−1) with a low activation energy of 0.17 *** allow for homogeneous Li deposition and highly reversible Li plating/stripping for over 2000 *** a proof of concept,the LMB assembled with POC-based QSSE demonstrates extremely stable cycling performance with 85%capacity retention after 1000 ***,our work demonstrates the practical applicability of POC as SSEs for LMBs and could be extended to other energy-storage systems,such as Na and K batteries.

关键词： Porous organic cage Cavity-induced anion-trapping Quasi-solid-state electrolyte Homogeneous Li+flux Lithium metal battery

Burden of mental disorders and risk factors in the Western Pacific region from 1990 to 2021

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World Journal of Psychiatry 2025年第1期15卷 93-105页

作者： Ya-Xin Xu xiao-Xuan niu wen-Chang Jia Jing wen Xue-Lin Cheng Yan Han Ming-Hui Peng Jing Zhou Yao Liu Sun-Fang Jiang xiao-Pan Li Department of Health Management Centre Zhongshan HospitalFudan UniversityShanghai 200030China Department of General Practice Zhongshan HospitalFudan UniversityShanghai 200030China Department of Nutrition Zhongshan HospitalFudan UniversityShanghai 200032China School of Public Health Fudan UniversityShanghai 200032China

BACKGROUND The burden of mental disorders(MD)in the Western Pacific Region(WPR)re-mains a critical public health concern,with substantial variations across demogra-phics and *** To analyze the burden of MD in the WPR from 1990 to 2021,along with associated risk factors,to reveal changing trends and emerging *** We used data from the Global Burden of Disease 2021,analyzing prevalence,incidence,and disability-adjusted life years(DALYs)of MD from 1990 to *** methods included age-standardisation and uncertainty analysis to address variations in population structure and data *** Between 1990 and 2021,the prevalence of MD rose from 174.40 million cases[95%uncertainty interval(UI):160.17-189.84]to 234.90 million cases(95%UI:219.04-252.50),with corresponding DALYs increasing from 22.8 million(95%UI:17.22-28.79)to 32.07 million(95%UI:24.50-40.68).During this period,the burden of MD shifted towards older age *** and anxiety disorders were predominant,with females showing higher DALYs for depressive and anxiety disorders,and males more affected by conduct disorders,attention-deficit hyperactivity disorder,and autism spectrum ***,New Zealand,and Malaysia reported the highest burdens,whereas Vietnam,China,and Brunei Darussalam reported the ***,childhood sexual abuse and bullying,and intimate partner violence emerged as significant risk *** This study highlights the significant burden of MD in the WPR,with variations by age,gender,and *** coronavirus disease 2019 pandemic has exacerbated the situation,emphasizing the need for a coordinated response.

关键词： Mental disorders Western pacific region Global Burden of Disease Risk factors Disability-adjusted life years

Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-Hui Zhang Zhi-Lai Zhan Guang-Lu Chang Yan Gao xia Li wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

化妆品行业产品力诉求与消费者需求的关系研究

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日用化学品科学 2014年第8期37卷 14-17页

作者：曾凡蕴牛文霞符移才胡国胜上海相宜本草化妆品股份有限公司上海200444

随着国内化妆品行业的快速发展,孕育着良好市场机遇的同时也面临着与国际化妆品品牌的激烈竞争。因此,提升产品力至关重要,同时,需将产品力的核心要素有效、准确地传达给目标消费群体,产品力的提升才具有现实意义。结合文献研究及案例分... 详细信息

随着国内化妆品行业的快速发展,孕育着良好市场机遇的同时也面临着与国际化妆品品牌的激烈竞争。因此,提升产品力至关重要,同时,需将产品力的核心要素有效、准确地传达给目标消费群体,产品力的提升才具有现实意义。结合文献研究及案例分析,将化妆品行业的产品力要素细化,深入分析各要素内涵,并将产品各要素与消费者对化妆品的功能需求及心理需求紧密结合,从理论和实践层面双重解析如何将产品力诉求有效地转化为市场需求。

关键词：化妆品产品力消费者

A Distributed Monthly Water Balance Model for Analyzing Impacts of Land Cover Change on Flow Regimes

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Pedosphere 2005年第6期15卷 761-767页

作者： xia Jun WANG Gang-Sheng YE Ai-Zhong niu Cun-wen Key Lab. of Water Cycle ＆ Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China）. State Key Lab. of Water Resources ＆ Hydropower Engineering Sciences Wuhan University Wuhan 430072 （China）

The Miyun Reservoir is the most important water source for Beijing Municipality, the capital of China with a population of more than 12 million. In recent decades, the inflow to the reservoir has shown a decreasing trend, which has seriously threatened water use in Beijing. In order to analyze the influents of land use and cover change (LUCC) upon inflow to Miyun Reservoir, terrain and land use information from remote sensing were utilized with a revised evapotranspiration estimation formula; a water loss model under conditions of human impacts was introduced; and a distributed monthly water balance model was established and applied to the Chaobai River Basin controlled by the Miyun Reservoir. The model simulation suggested that not only the impact of land cover change on evapotranspiration, but also the extra water loss caused by human activities, such as the water and soil conservation development projects should be considered. Although these development projects were of great benefit to human and ecological protection, they could reallocate water resources in time and space, and in a sense thereby influence the stream flow.

关键词： distributed monthly water balance model land use and cover change (LUCC) remote sensing scenario analysis

Determination of a Reasonable Percentage for Ecological Water-Use in the Haihe River Basin, China

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Pedosphere 2006年第1期16卷 33-42页

作者： xia Jun FENG Hua-Li ZHAN Che-Sheng niu Cun-wen Key Laboratory of Water Cycle ＆ Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 （China）. State Key Laboratory of Water Resources ＆ Hydropower Engineering Sciences Wuhan University Wuhan 430072（China） Nanjing Hydraulic Research Institute Nanjing 210029 （China）

An investigation was conducted to study problems of determining a reasonable percentage for ecological water-use in the Haihe River Basin of China. Three key aspects for the ecological water requirement （EWR） were analyzed, involving i） the EWR for river system, ii） the EWR for wetlands and lakes, and iii） the EWR for discharge into the sea to maintain the estuary ecological balance of the Haihe River. The Montana method and related water level-flow relationships, and the statistic approach based on hydrological records were applied to estimate different components of EWR. The results showed that the total ecological water demand in the region, was about 3.47-14.56 billion m^3. Considering flow regime change and uncertainty, the ecological water demand could be estimated by the hydrological frequency approach. Preliminary analysis showed that for different annual runoff under the frequencies of 20%, 50%, 75% and 95%, the ecological water demand approached 12%-50%, 18%-74%, 24%-103%, 35%-148% and 16%-66%, respectively. By further analysis to balance ecological water-use and socioeconomic water-use, the rational percentage of ecological water-use was estimated as 35%-74%, that provides useful information to judge whether the allocation of water resources is reasonable, and was proved to be satisfactory by comparing with the practical condition.

关键词： ecological water requirement ecological water-use Haihe River Basin

Heteroepitaxial growth of Au@Pd core–shell nanocrystals with intrinsic chiral surfaces for enantiomeric recognition

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Rare Metals 2024年第1期43卷 225-235页

作者： Feng-xia Wu Feng-Hua Li xia-Li Lv Qi-xian Zhang Guo-Bao Xu wen-Xin niu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312000China University of Science and Technology of China Hefei 230026China School of Materials Science and Engineering Shanghai UniversityShanghai 200436China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314113China University of Chinese Academy of Sciences Beijing 100039China

Noble metal surfaces with intrinsic chirality serve as an ideal candidate for investigating enantioselective chemistry due to their superior chemical durability and high catalytic ***,significant advance has been made in synthesizing metal nanocrystals with intrinsic ***,the majority reports are limited to ***,through a heteroepitaxial growth strategy,the synthesis of metal nanocrystals with intrinsic chirality to palladium was extended for the first time and their application in enantioselective recognition was *** heteroepitaxial growth strategy allows for transferring the chirality of homochiral Au nanocrystals to Au@Pd core–shell *** employing the chiral Au@Pd nanocrystals as enantiomeric recognizing elements,a series of electrochemical sensors for chiral discrimination were *** optimal conditions,the peak potential between D-dihydroxyphenylalanine(D-DOPA)and L-dihydroxyphenylalanine(L-DOPA)is about 80 m V,and the peak current of D-DOPA is 2 times as much as that of L-DOPA,which enables the determination of the enantiomeric excess(EE,%)of ***,this report not only introduces a heteroepitaxial growth strategy to synthesize metal nanocrystals with intrinsic chirality,but also demonstrates the superior capability of integrating intrinsic chirality and catalytic properties into metal nanocrystals for chiral recognition.

关键词： Core–shell nanostructures Chirality transfer Electrochemical sensors Chiral recognition Chiroplasmonics