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微量供油下的线接触副润滑增效分析

中国机械工程 2024年第7期35卷 1205-1211页

作者：李书义郭峰黄柏林金薇梁鹏青岛理工大学机械与汽车工程学院青岛266520 香港城市大学机械工程系中国香港999077

实验发现亲/疏油交替供油的功能润湿表面能提高微量供油下有效润滑的成膜性能。基于此,建立了有限长滚子副润滑模型,分析了交替供油的亲/疏油带宽及工作参数对润滑性能的增强规律。研究发现,微量供油条件下可利用交替供油方式达到线接... 详细信息

实验发现亲/疏油交替供油的功能润湿表面能提高微量供油下有效润滑的成膜性能。基于此,建立了有限长滚子副润滑模型,分析了交替供油的亲/疏油带宽及工作参数对润滑性能的增强规律。研究发现,微量供油条件下可利用交替供油方式达到线接触副润滑增效的目的,但供油交替变换使接触区润滑性能不稳定,且润滑增效作用会受功能表面亲/疏油带宽和卷吸速度的影响。

关键词：线接触副微量润滑功能表面供油

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Stripe theory based numerical method for solving asymmetrical hysteresis of friction force in linear rolling guideways

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Science China(Technological Sciences) 2016年第9期59卷 1320-1327页

作者： ZHAO Yang XI YinHu MAO JunHong wong patrick pat lam Theory of Lubrication and Bearing Institute Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi'an Jiaotong University Department of Mechanical and Biomedical Engineering City University of Hong Kong

Linear rolling guideways(LRGs) play an important role in precision engineering. In the pre-rolling region, the hysteretic friction force exerts great impacts on the positioning accuracy. Numerical and experimental studies of the hysteresis of friction force are presented in this paper. A model, which is based on the stripe theory and the simplified theory of rolling contact, is built to describe the transient hysteresis of the friction force. Then, the model is modified by taking the anelasticity effect into consideration. Experimentally, a linear motor direct-drive setup is utilized to measure the transient asymmetrical hysteresis of the friction force in the pre-rolling region of an LRG. The influences of the pre-rolling displacement and the dwelling time on the asymmetrical hysteresis of the friction force are studied. The numerical and experimental results are well correlated, which shows good accuracy of the model. The transient asymmetrical hysteresis of friction force in the pre-rolling region of LRGs can thus be determined using the model.

关键词：直线滚动导轨摩擦力数值方法纹理不对称滞回求解滞后现象

限量供油条件下硬脂酸吸附对面接触润滑油膜的影响

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机械工程学报 2023年第21期59卷 321-329页

作者：简煜升荆兆刚郭峰黄柏林韩素立栗心明青岛理工大学机械与汽车工程学院青岛266520 香港城市大学机械工程系中国香港999077

在限量供油条件下,利用滑块-盘面接触润滑油膜测量系统研究了PAO10(聚α-烯烃)添加硬脂酸对油膜厚度-滑块倾角关系的影响,理论分析了滑块入口润滑油堆积对润滑油膜承载力的影响,并对硬脂酸在固体表面的吸附进行了表征。结果表明,油膜厚... 详细信息

在限量供油条件下,利用滑块-盘面接触润滑油膜测量系统研究了PAO10(聚α-烯烃)添加硬脂酸对油膜厚度-滑块倾角关系的影响,理论分析了滑块入口润滑油堆积对润滑油膜承载力的影响,并对硬脂酸在固体表面的吸附进行了表征。结果表明,油膜厚度随滑块倾角的增加呈现总体下降的趋势。硬脂酸吸附诱导的“反润湿”作用,使润滑油在润滑轨道上由经典双侧脊分布转变为离散态条状或液滴状分布,改善了接触区入口供油,提高油膜厚度。实验发现了较低的滑动速度下低供油量反而诱发高油膜厚度的“异常”现象。硬脂酸的吸附使得润滑油在入口区形成非浸润的液滴状堆积,形成的附加拉普拉斯压力增加油膜承载力;当供油量较低时,入口润滑剂堆积的曲率半径较小,附加拉普拉斯压力较大,因此膜厚较高。

关键词：硬脂酸限量供油倾角膜厚面接触

流体润滑条件下BSA水溶液吸附膜的光干涉测量

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摩擦学学报 2014年第6期34卷 658-664页

作者：李霞郭峰黄柏林青岛理工大学机械学院山东青岛266033 香港城市大学机械及生物医学工程系

利用面接触流体润滑光干涉测量装置,对BSA水溶液的润滑和吸附特性进行了试验研究.试验中润滑接触副由静止的钢块和旋转的玻璃盘组成,结果表明润滑膜厚度随速度的增加而增加,随载荷的增加而减小.BSA在钢滑块表面形成两种类型的吸附,一为... 详细信息

利用面接触流体润滑光干涉测量装置,对BSA水溶液的润滑和吸附特性进行了试验研究.试验中润滑接触副由静止的钢块和旋转的玻璃盘组成,结果表明润滑膜厚度随速度的增加而增加,随载荷的增加而减小.BSA在钢滑块表面形成两种类型的吸附,一为连续的薄膜层,二为离散的蛋白质凝聚团簇.同时证实了钢块表面微观腐蚀的发生,并由入口区向出口区扩展,该腐蚀促进吸附膜的增长.吸附层的形成受润滑膜剪应变率和压力的影响,高的剪应变率和低的载荷有利于吸附膜的增长.

关键词：面接触流体润滑光干涉 BSA 吸附

Mothers’ health-related quality of life: Its relationship with children’s health-related quality of life and behavior in low-income families

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Family Medicine and Community Health 2016年第4期4卷 4-12页

作者： Rosa Sze Man wong Vivian Yawei Guo patrick Ip Carlos King Ho wong Esther Yee Tak Yu Colman Siu Cheung Fung Cindy Lo Kuen lam Department of Family Medicine and Primary Care The University of Hong KongAp Lei Chau ClinicAp Lei ChauHong KongChina Department ofPaediatrics and Adolescent Medicine TheUniversity of Hong KongQueen Mary HospitalHong KongChina

Objective:To examine the association between mothers’health-related quality of life(HRQOL)and their children’s HRQOL and behavior in low-income ***:Mothers of 278 children aged 6-12 years from low-income families were invited to complete the Child Health Questionnaire Parent Form 50(CHQ-PF50)and the Strength and Dif-ficulties Questionnaire(SDQ)for their children as well as the 12-item Short-Form Health Survey version 2(SF-12v2)and the patient Health Questionnaire-2(PHQ-2).Multiple linear regressions with mother-child pairs as the unit of analysis were performed to examine the associations between maternal and child variables with adjustment of mother-and child-level ***:Compared with the general population,low-income mothers had a lower mean SF-12v2 mental component summary score and their children also had lower mean CHQ-PF50 physi-cal and psychosocial summary scores and SDQ total difficulties *** of mothers with SF-12v2 scores below the population mean of 50 had significantly worse CHQ-PF50 scores and higher SDQ total difficulties *** mother’s PHQ-2 depression status had no association with the child’s CHQ-PF50 ***:Our findings suggest that more attention should be paid to reducing the negative impact of health problems on mothers’daily roles in childcare in low-income families.

关键词： Health-related quality of life child health child behavior low income

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界面滑移条件下弹流油膜的试验观察

机械工程学报 2007年第10期43卷 36-40页

作者：郭峰黄柏林付忠学青岛理工大学机械工程学院青岛266033 香港城市大学制造工程与工程管理学系

在极低速纯滑动条件下完成高粘度聚丁烯弹流油膜的光干涉测量试验,观察到明显的油膜入口凹陷现象。试验结果表明,入口凹陷的深度随载荷的增加而增加,随卷吸速度的增加存在一个极大值。试验中润滑剂的粘度越高,入口凹陷越容易出现。纯滑... 详细信息

在极低速纯滑动条件下完成高粘度聚丁烯弹流油膜的光干涉测量试验,观察到明显的油膜入口凹陷现象。试验结果表明,入口凹陷的深度随载荷的增加而增加,随卷吸速度的增加存在一个极大值。试验中润滑剂的粘度越高,入口凹陷越容易出现。纯滑动条件下,油膜厚度对速度和载荷的依赖关系明显偏离了经典的弹流理论。试验中观察到的入口凹陷证明了已有入口凹陷弹流数值分析的正确性。

关键词：弹性流体动力润滑极限切应力界面滑移入口凹陷

Maintenance and Management of Existing Residential Buildings in Hong Kong

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Maintenance and Management of Existing Residential Buildings...

工程科技论坛第70场

作者： Francis K.W.wong patrick T.I.lam Department of Building and Real Estate The Hong Kong Polytechnic University Department of Building and Real Estate The Hong Kong Polytechnic University

＜正＞Introduction Maintenance and management of existing residential buildings is a major concern in Hong Kong, particularly for the ageing residential buildings in densely populated urban *** there are 31,334 domestic and composite buildings in Hong Kong（wong,2007b）.About 22 % of these buildings are between 20 and 29 years old and about 34 % are at 30 years old or above

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基于双色光干涉的面接触润滑油膜在线测量

摩擦学学报 2017年第3期37卷 283-289页

作者：白清华郭峰姜培刚黄柏林青岛理工大学计算机工程学院山东青岛266520 青岛理工大学机械工程学院山东青岛266520 香港城市大学机械与生物医学工程系香港九龙999077

根据面接触润滑油膜红绿双色光干涉强度调制信号,构造了基于光流和动态时间弯曲技术的追踪算法,对一维调制光强曲线上与膜厚具有对应关系的特定目标区域进行实时追踪,从而实现了在线实时膜厚测量.通过与稳态离线测量结果对比,验证了该... 详细信息

根据面接触润滑油膜红绿双色光干涉强度调制信号,构造了基于光流和动态时间弯曲技术的追踪算法,对一维调制光强曲线上与膜厚具有对应关系的特定目标区域进行实时追踪,从而实现了在线实时膜厚测量.通过与稳态离线测量结果对比,验证了该在线测量系统的准确性和可靠性.利用该系统对三角波形式变速过程中流体动压润滑瞬时膜厚进行了测量,揭示了膜厚滞后于速度变化的规律.

关键词：光干涉油膜厚度面接触在线测量

A six-year descriptive epidemiological study of human coronavirus infections in hospitalized patients in Hong Kong

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Virologica Sinica 2016年第1期31卷 41-48页

作者： Cyril C.Y.Yip Carol S.F.lam Hayes K.H.Luk Emily Y.M.wong Rodney A.Lee Lok-Yee So Kwok-Hung Chan Vincent C.C.Cheng Kwok-Yung Yuen patrick C.Y.Woo Susanna K.P.Lau Department of Microbiology The University of Hong Kong Department of Microbiology Pamela Youde Nethersole Eastern Hospital Department of Paediatrics and Adolescent Medicine Pamela Youde Nethersole Eastern Hospital Research Centre of Infection and Immunology The University of Hong Kong State Key Laboratory of Emerging Infectious Diseases The University of Hong Kong

We conducted a six-year epidemiological study on human coronaviruses(HCoVs) circulating in Hong Kong, using 8275 nasopharyngeal samples from patients with acute respiratory tract infections. HCoVs were detected in 77(0.93%) of the samples by a pan-HCoV RT-PCR assay. The most frequently detected HCoV species was HCoV-OC43(0.58%), followed by HCoV-229E(0.15%),HCoV-HKU1(0.13%) and HCoV-NL63(0.07%). HCoVs were detected throughout the study period(September 2008–August 2014), with the highest detection rate from September 2010 to August2011(22/1500, 1.47%). Different seasonal patterns of each HCoV species in Hong Kong were ***-OC43 was predominant in the fall and winter, whereas HCoV-HKU1 showed peak activity in winter, with a few cases occurred in spring and summer. HCoV-229 E mainly occurred in winter and spring, while HCoV-NL63 was predominant in summer and autumn. HCoVs most commonly infect the elderly and young children, with median age of 79.5 years(range, 22 days to 95 years).Intriguingly, the detection rate of HCoV-OC43 in the age group of > 80 years(26/2380, 1.09%) was significantly higher than that in the age group of 0–10 years(12/2529, 0.47%)(P < 0.05). These data provides new insight into the epidemiology of coronaviruses.

关键词：病毒学临床医学药物学