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Effect of amide type modified rapeseed oil as lubricating additive on friction and wear behavior of steel-steel and steel-aluminum alloy systems

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 435-438页

作者： FANG Jian-hua CHEN Bo-shui liu wei-min DONG Lin WANG Jiu Department of Petrochmistry Logistical Engineering University Chongqing 400016 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Department of Petrochmistry Logistical Engineering University Chongqing 400016 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Department of Petrochmistry Logistical Engineering University Chongqing 400016 China Department of Petrochmistry Logistical Engineering University Chongqing 400016 China

A new type of environmentally friendly lube additive-amide type modified rapeseed oil was synthesized and characterized by infrared spectrum. Its effect on the friction and wear behavior of steel-steel and steel-aluminum alloy systems were investigated with a four-ball machine and an Optimol SRV friction and wear tester *** morphographies of the worn surfaces were analyzed by means of scanning electron microscopy(SEM). The worn surfaces of the 2024Al alloy block were analyzed by means of X-ray photoelectron spectroscopy(XPS). The results show that the modified rapeseed oil as additives can obviously decrease the wear rate and friction coefficient of steel pair and steel-aluminum frictional pair. Its lubrication mechanism is inferred that a high strength complex protection films form on the worn surface of the Al alloy due to the adsorption or tribochemistry reaction of a long chain additive molecule and high reaction activity of N element.

关键词： environmentally friendly lube additive amide type rapeseed oil steel-steel pair steel-aluminum alloy pair tribochemistry

Cuticular protein gene LmACP8 is involved in wing morphogenesis in the migratory locust,Locusta migratoria

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Journal of Integrative Agriculture 2021年第6期20卷 1596-1606页

作者： ZHAO Xiao-ming YANG Jia-peng GOU Xin liu wei-min ZHANG Jian-zhen Institute of Applied Biology Shanxi UniversityTaiyuan 030006P.R.China College of Life Science Shanxi UniversityTaiyuan 030006P.R.China

Cuticular proteins(CPs)are major components of the insect cuticle-associated organs such as integument and wings,although the importance of CPs for wing development and function in hemimetabolous insects remains *** the present study,a wing cuticular protein LmACP8 was identified from Locusta migratoria,which belongs to the RR-2 subfamily of cuticular protein R&R consensus(CPR)chitin-binding ***8 was mainly expressed in the wing pads and showed high expression levels before ecdysis of third-,fourth-,and fifth-instar nymphs,with its encoded protein located in the procuticle of wing pads and adult *** of LmACP8 by RNA interference markedly reduced the amount of its protein,which consequently caused abnormal wing morphogenesis in the transition from nymph to adult of *** further demonstrated that the abnormal morphogenesis was caused by severe damage of the endocuticle in the ***8 was suppressed by 20-hydroxyecdysone(20 E)in vivo,however,its expression was significantly up-regulated after knocking down the hormone receptor gene ***,the LmACP8 that is negatively regulated by the LmHR39-mediated 20 E signaling pathway is involved in wing development during the nymph to adult transition.

关键词： cuticular proteins LmACP8,20-hydroxyecdysone wing development

Effect of NF-κB and p38 MAPK in activated monocytes/macrophages on pro-inflammatory cytokines of rats with acute pancreatitis

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World Journal of Gastroenterology 2003年第11期9卷 2513-2518页

作者： Hong-Shan liu Cheng-En Pan Qing-Guang liu wei Yang Xue-min liu, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi’an Jiaotong University, Xi’an 710061, Shaanxi Province, China Department of Hepatobiliary Surgery First Affiliated Hospital Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China.

AIM: Proinfiammatory cytokines TNF-α and IL-6 play a main role in acute pancreatitis (AP). Cytokine biosynthesis runs through two major signaling pathways at the level of proteins: nuclear transcription factor-κB (NF-κB) and p38 mitogen-activated protein kinase (p38 MAPK). The aim of the study was to investigate the effect of NF-κB and p38 MAPK in activated monocytes/macrophages on cytokines of rats with acute ***: Taurocholate (3 % and 5 %) at doses of 1 mL/kg was administered into the biliopancreatic duct of male Sprague-Dawley (SD) rats to reduce acute edematous pancreariris (AEP) and acute necrotizing pancreatitis (ANP).Pancreatic tissues were prepared immediately after *** this point, blood was obtained for determination of serum amylase and pro-inflammatory TNF-α and IL-6. Activated monocytes/macrophages were captured from blood and so were ascites. NF-κB and p38 MAPK in activated monocytes/macrophages were measured by immunohistochemistry method. Pancreatic tissue samples were prepared for routine light microscopy, using hematoxylin and eosin (HE) ***: The serum levels of amylase were 3 056.00±1 232.35 IU/L and 4 865.12±890.34 IU/L at 3 and 6 hours in ANP group, which were significantly higher than those (3 056.00±1 232.35 TU/L and 3 187.17±821.16 IU/L) (P<0.05,respectively) in AEP group. In ascites the levels were 3.32±1.01 g and 3.76±1.12 g at 3 and 6 hours in ANP group,which were significantly higher than those (1.43±1.02 g and 2.56±1.21 g) (P<0.05, respectively) in AEP group. The serum levels of TNF-α were 54.27±23.48 pg/ml and 67.83±22.02 pg/ml in AEP group and 64.28±20.79 pg/ml and 106.59±43.71 pg/ml in ANP group, and the serum levels of IL-6 were 428.12±140.30 pg/ml and 420.13±139.40 pg/ml in AEP group and 1 600.32±309.78 pg/ml and 2 203.76±640.85 pg/ml in ANP group, which were far significantly higher than those in sham group (P<0.001, respectively). The serum level of TNF-α 6 hours after establishment of the studie

关键词：急性胰腺炎 TNF-α IL-6 细胞因子发病机制核转录因子-κB p38MAPK

The Potential of Duck Hepatitis Virus(DHV-1) Stimulating the Body weight Gain and the Effects of Silymarin on It in Duckling

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Agricultural Sciences in China 2009年第11期8卷 1403-1408页

作者： liu wei-min WANG Bing-yun CHEN Jian-hong WANG Jun JI Hui-qin YUAN Sheng HUANG De-chun LI Kang-lin College of Life Science Foshan University Foshan 528231 P.R.China

To evaluate the effects of duck hepatitis virus-1 （DHV-1） on the body weight gain in duck and the effects of silymarin on it in vivo, 100 10-d-old ducks, both male and female, were collected to be subjected to the test. The experiments were conducted in 8 groups： in group 1-3, the animals were inoculated with 1：105 diluted duck hepatitis virus （DHV-1） infected allantoic fluid and given 0, 30, and 50 mg kg^-1 BW d^-1 silymarin orally, respectively. In group 4-6, the animals were inoculated with 1：5 × 105 diluted DHV-1 infected allantoic fluid and given 0, 10, and 30 mg kg^-1 BW d^-1 silymarin orally, respectively. In group 7, the animals were given 10 mg kg^-1 BW d^-1 silymafin only. Group 8 was the control one treated by injecting sterillized saline into the leg muscles. All the silymarin was given from 0 to 4 d after inoculation of the virus. By the 5th d after inoculation, the vein blood was drawn from the dorsal foot vein and the plasma samples were collected and stored at -20℃. The body weight gain （BWG） was measured from 0 to 10 d after inoculation. The plasma IGF-I, T3, and T4 concentrations were measured by radioimmunoassay （RIA）. At the virus dose of 1：5 ×105 diluted virus infected allantoic fluid, the inoculation of the virus enhanced the BWG significantly compared with that of the control （P〈 0.01）, while 10-50 mg kg^-1 BW d^-1 silymarin could counteract the effects of the virus on the BWG dose-dependently. The plasma IGF-I levels showed no correlation with the BWG, but the T3 levels showed a same tropism with the body weight gain. The present results indicated that sublethal DHV-1 enhanced the body weight gain of ducklings significantly, and the silymarin could counteract this effect in vivo.

关键词： duck hepatitis virus-l DHV body weight gain silymarin infection duckling

纳米Cu在聚乙二醇溶液中的摩擦磨损性能研究

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摩擦学学报 2005年第5期25卷 385-389页

作者：李斌夏延秋王晓波薛群基 liu wei-min 中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000山东教育学院化学系山东济南250013 沈阳工业大学机械工程学院辽宁沈阳110023 中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000

采用原位合成法以聚乙二醇400作为反应介质,以氢氧化钠和氨基配体作为分散剂,用乙二醇还原六水合乙酸铜制备出纳米Cu粉和纳米Cu聚乙二醇溶液,用X射线衍射仪和透射电子显微镜表征其结构,在四球摩擦磨损试验机上评价了含不同质量分数纳米... 详细信息

采用原位合成法以聚乙二醇400作为反应介质,以氢氧化钠和氨基配体作为分散剂,用乙二醇还原六水合乙酸铜制备出纳米Cu粉和纳米Cu聚乙二醇溶液,用X射线衍射仪和透射电子显微镜表征其结构,在四球摩擦磨损试验机上评价了含不同质量分数纳米铜粉的聚乙二醇溶液的摩擦磨损性能,并与分散剂进行对比.结果表明:所制备的纳米铜粒径约5 nm且分布均匀;纳米Cu粉可以显著提高聚乙二醇的抗磨和减摩性能.这是由于纳米铜在钢球磨斑表面形成了铜沉积膜和微量的一价氧化铜.

关键词：纳米铜聚乙二醇合成油摩擦磨损性能

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股票收益反转效应及与买卖价差关系研究

管理科学学报 2016年第6期19卷 171-182页

作者：董晨昱刘维奇 liu wei-min 王钰山西大学数学科学学院太原030006 山西大学管理与决策研究中心太原030006 山西财经大学财政金融学院太原030006 山西大学软件学院太原030006

研究了买卖价差与股票短期收益反转的关系.拓展了"真实"价格保持不变或遵循随机游走的假设,在三种情形下对比连续时间上观测价格和"真实"价格的路径图及其价格变化的联合分布来分析买卖价差对股票短期收益反转的影响,结果表明,当"真实"... 详细信息

研究了买卖价差与股票短期收益反转的关系.拓展了"真实"价格保持不变或遵循随机游走的假设,在三种情形下对比连续时间上观测价格和"真实"价格的路径图及其价格变化的联合分布来分析买卖价差对股票短期收益反转的影响,结果表明,当"真实"收益的一阶自相关系数接近于0时,买卖价差是造成观测收益反转的唯一原因;当"真实"收益有较强的一阶负自相关性时,买卖价差对观测收益反转的作用不再明显,甚至可能减弱此效应;买卖价差加剧了观测收益的波动.通过买卖价差与股票观测收益间的恒等关系,建立了收益分解模型,将"真实"收益从观测收益中分离,随后使用NASDAQ市场的个股日、周和月数据进行横截面回归和方差比检验,实证结果也支持上述结论.

关键词：收益反转买卖价差方差比检验

STRUCTRE AND PROPERTIES OF COMPOSITE Ni/HARD CARBON FILMS PREPARED BY PLASMA DEPOSITION

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Journal of Energy Chemistry 1996年第2期 176-184页

作者： CAO wei-min ZHOU Kun-Lin(Chengdu Institute of Organic Chemistry The Chinese Academy of Sciences Chengdu, Sichuan 610041)liu wei-min(Laboratory of Solid Lubrcation Lanzhou Institute of Chemical Physics. The Chinese Academy of Sctences Lanzhou. Gansu 73000

Composite Ni/hard carbon films have been prepared by the decomposition of an Ni(CO)4/CH4 mixture in an r f glow discharge The deposition rate of the films was studied The film structure was characterixed by IR XPS AES TEM and electron diffraction Ni atom content was varied from 4 to 75% Films with low Ni content were amorphous and high Ni content ones showed crhystalline features of metallic Ni and N2O3 The electrical resistivity and film transmission in the visivle region decrasesed with Ni content increase that can be adjusted by changing the deposition conditions

关键词： Ni/hard carbon films plasma decomposition deposition rate

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亲油性LaF_3纳米粒子的制备及表征

功能材料 2006年第3期37卷 437-439页

作者：陈爽刘维民五邑大学化学与环境工程系广东江门529020 中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000

在醇-水混合溶剂中合成了表面为油酸修饰的LaF3纳米粒子,并用透射电子显微镜、红外光谱和X射线粉末衍射仪对修饰LaF3纳米粒子进行了表征。结果表明:所制备的修饰LaF3纳米粒子大小均匀,粒径约为8nm;其纳米核为六方结构的LaF3;由于表面修... 详细信息

在醇-水混合溶剂中合成了表面为油酸修饰的LaF3纳米粒子,并用透射电子显微镜、红外光谱和X射线粉末衍射仪对修饰LaF3纳米粒子进行了表征。结果表明:所制备的修饰LaF3纳米粒子大小均匀,粒径约为8nm;其纳米核为六方结构的LaF3;由于表面修饰剂油酸与LaF3纳米粒子表面之间发生化学键合作用,使得油酸修饰LaF3纳米粒子在苯及润滑油中的分散性明显提高。

关键词：表面修饰 LaF3纳米粒子分散性

Lubrication Mechanism of Micro/Nano-particles on Sialon

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Journal of Wuhan University of Technology(Materials Science) 2004年第B10期19卷 5-7页

作者：张文光 Shanghai Jiaotong University

The tribological properties of Sialon sliding against AISI52100 steel ball under the lubrication of solid particle additives, as micro-borate particle and nano-PbS particle, were evaluated by a SRV ball-on-disc test rig. The chemical composition of the worn surface was characterized by X-ray photoelectron spectroscopy (XPS). The morphologies of the worn surfaces of Sialon were analyzed by scanning electron microscopy (SEM). The results show that the particles can reduce the friction coefficient of the pairs and the wear volume of Sialon significantly. The wear resistance of micro-borate is superior to that of nano-PbS while the friction-reducing ability of PbS is better than that of borate. According to the XPS and SEM results, the wear resistance of PbS is mainly depended on the tribochemical film mainly composed of PbSO 4, which deposited on the worn surface with good bonding strength. No tribochemical reaction or deposited film was detected or observed on the worn surface of Sialon under the lubrication of borate, indicating that the possible physically deposited film generated from micro particle can also greatly reduce the wear volume of Sialon, though the friction reducing ability of which is inferior to that of nano PbS particle.

关键词： sialon ceramic micro/nano-particle additive lubrication mechanism