共查询到19条相似文献,搜索用时 78 毫秒
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本文合成了一系列2,4-双-二正丁胺基-6-(0,0’-二正烷基二硫代磷酸酯)基-s-1,3,5-均三嗪衍生物。利用四球摩擦磨损试验机考察了它们的摩擦学性能。实验结果表明,该类化合物具有良好的极压抗磨性能,能很大地提高双酯的极压抗磨性能。用X射线光电子能谱(XPS)分析了钢球磨损表面典型元素的化学状态,并探讨了该类添加剂的摩擦学机理。结果表明,在摩擦过程中,钢球表面形成了一层含硫,磷的富氧膜和有机氮复合膜,这种复合膜是添加剂具有优异摩擦学性能的主要原因。 相似文献
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以2-[2-苯并噻唑基]为原料合成了2-[2-苯并噻唑基]硫代乙醇(BTE),再以该BTE合成了一种含氮硫杂环硼酸酯(SNHB)添加剂,并采用FTIR、元素分析对其结构进行了表征。考察了BTE、SNHB的油溶性、热稳定性以及SHNB的水解稳定性。采用四球摩擦磨损试验研究了BTE及SNHB在菜籽油中的减摩、抗磨以及极压性能。采用SEM、EDS观察和分析了钢球磨斑表面形貌及元素。研究结果表明,合成的产物为目标产物BTE和SNHB;在相同的试验条件下,SNHB和BTE在菜籽油中完全溶解,具有较好的油溶性;SNHB和BTE的分解温度范围分别是从270.50~396.01℃、253.04~326.83℃,两者均具有良好的热稳定性,且SNHB的热稳定性优于BTE;SNHB的水解时间超过7天,而市售的硼酸三异丙酯仅为10 min,SNHB有较好的水解稳定性;在不同载荷、添加比例等条件下SNHB的摩擦学性能明显优于BTE。 相似文献
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凹凸棒石粉体作为润滑油添加剂的摩擦学性能 总被引:3,自引:0,他引:3
采用摩擦磨损试验机研究了凹凸棒石粉体作为润滑油添加剂对钢-钢摩擦副的减摩抗磨性能,采用扫描电子显微镜和能量色散谱仪分析了磨损表面的微观形貌及元素组成,采用三维轮廓测量仪测量了磨痕宽度和体积,探讨了凹凸棒石粉体的减摩抗磨机理.结果表明:在润滑油中添加0.5%(质量分数)以上的凹凸棒石粉体时,能显著降低钢-钢摩擦副的摩擦系数.添加量为1.0%时具有最佳的减摩抗磨性.通过摩擦物理和摩擦化学作用,凹凸棒石粉体在磨损表面形成光滑平整的修复层,从而提高摩擦副的摩擦学性能. 相似文献
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设计合成了4种含氮杂环的酯或酰胺类衍生物润滑油添加剂(Ⅰ~Ⅳ)。采用核磁共振氢谱(1H NMR)和飞行时间质谱(MALDI-TOF-MS)对所得产物的结构进行了表征;研究了4种添加剂的油溶性、热稳定性和抗腐蚀性;在四球摩擦磨损试验机上系统考察了添加剂在液体石蜡中的摩擦学性能;利用扫描电子显微镜(SEM)和能谱分析仪(EDS)观察和分析了钢球磨斑的表面形貌和元素组成。结果表明,4种添加剂均具有良好的油溶性、热稳定性和抗腐蚀性,当添加剂Ⅰ的质量分数达到1.0%时,钢球的磨斑直径(WSD)和摩擦系数分别比在液体石蜡中降低了33%和26%。SEM结果显示4种添加剂的加入能明显减小WSD,减少表面磨损,EDS结果表明添加剂在摩擦过程中形成了复杂的反应膜。 相似文献
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为研究坡缕石/铟复合纳米添加剂对润滑油摩擦性能的影响,选取精炼菜籽油作为基础油,分别对加入不同配比添加剂的试油进行四球摩擦磨损试验机的极压试验和长磨试验.结果表明,当坡缕石/铟复合纳米添加剂在润滑油中的配比为1.5%时,润滑体系的摩擦性能最佳,与基础油相比,无卡咬最大负荷PB值提高了30.77%,烧结负荷PD值提高了一... 相似文献
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合成了一种油溶性化合物正十二烷硫基硼酸钡(Ba-SB),并将其作为润滑油添加剂,采用四球摩擦磨损试验机评价了其摩擦学性能。结果表明:该添加剂具有较好的油溶性能和热稳定性能。十二烷硫基硼酸钡使HVI500基础油的抗磨性能明显改善,承载能力得到明显提高,摩擦系数明显降低,采用扫描电镜对钢球磨斑表面形貌进行分析,加了该添加剂的钢球磨斑表面平整、光滑,犁沟浅且钢球磨斑表面有沉积物,从EDS谱图上可以看出摩擦副表面含有B、N、Cr、Fe、S元素。从XPS分析添加剂在摩擦过程中发生了摩擦化学降解反应,并在摩擦副表面生成了BaO,B2O3和FeB的个物质抗磨减摩膜,从而改善了其摩擦磨损性能。 相似文献
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合成4种2,5-二芳基-1,3,4-噻二唑化合物,即2,5-二苯基-1,3,4-噻二唑(DPTD),2,5-二(2-羟基苯)-1,3,4-噻二唑(2-DHPTD),2,5-二(3-羟基苯)-1,3,4-噻二唑(3-DHPTD)和2,5-二(4-羟基苯)-1,3,4-噻二唑(4-DHPTD)。通过Tafel极化曲线和电化学阻抗研究4种油溶型噻二唑衍生物在50 mg·L-1硫-乙醇体系中的缓蚀性能,电化学测试表明:腐蚀液中添加噻二唑衍生物后,银片腐蚀得到抑制;随着缓蚀剂浓度增大,腐蚀电流密度减小,缓蚀效率增大;当缓蚀剂浓度为90 mg·L-1时,4种缓蚀剂DPTD、2-DHPTD、3-DHPTD和4-DHPTD的缓蚀效率分别为85.8%、94.6%、96.4%和97.1%。采用扫描电子显微镜和原子力显微镜观察其表面形貌,可知缓蚀剂在金属表面形成一层保护膜,阻止腐蚀物质与金属表面的接触,从而抑制银片腐蚀。经分子动力学分析可知,4种噻二唑衍生物吸附于金属表面遵循Langmuir等温方程,且吸附属于以化学吸附为主的混合型吸附。量子化学计算和分子动力学模拟研究表明,4种缓蚀剂均具有很好的缓蚀作用,且4种缓蚀剂的缓蚀效率大小顺序是[4-DHPDT]> [3-DHPDT]> [2-DHPDT]> [DPDT],这与实验结果一致。 相似文献
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物理、化学性质特殊的纳米粒子在摩擦学领域引起了人们极大的兴趣,本文主要从纳米润滑油添加剂的结构与特性,摩擦学性能与润滑机理,纳米材料作为润滑油添加剂存在的问题及解决方法等几方面,介绍了纳米润滑油添加剂技术的研究进展,展望了纳米润滑油添加剂的发展前景,并指出了需要进一步深入研究的几个问题。 相似文献
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This paper deals with the hydroprocessing of rapeseed oil representing a perspective technological way for production of biocomponents in diesel fuel range. Rapeseed oil was hydroprocessed at various temperatures (260-340 °C) under a pressure of 7 MPa in a laboratory flow reactor. Three Ni-Mo/alumina hydrorefining catalysts were used. Reaction products were analyzed using several gas-chromatographic methods. Reaction products contained water, hydrogen-rich gas and organic liquid product (OLP). The main components of OLP were identified as C17 and C18n-alkanes and i-alkanes. At a low reaction temperature, OLP contained also free fatty acids and triglycerides. At reaction temperatures higher than 310 °C, OLP contained only hydrocarbons of the same nature as hydrocarbons present in diesel fuel. Influence of reaction temperature and catalyst on the composition of reaction products is discussed. 相似文献
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Electrochemical behavior of biphenyl as polymerizable additive for overcharge protection of lithium ion batteries 总被引:2,自引:0,他引:2
Electrochemical properties and working mechanism of biphenyl as a polymerizable electrolyte additive for overcharge protection of lithium ion batteries are studied by microelectrode voltammetry, charge-discharge measurements and SEM characterization of the overcharged cell’s components. The experimental results reveal that biphenyl can electrochemically polymerize at the overcharge potential of 4.5-4.75 V (versus Li/Li+) to form a layer of conductive film on the cathode surface and the polymer deposits may develop to penetrate the separator to reach the anode surface, resulting an internal short-circuit to prevent from the cell voltage runaway. On the other hand, the electro-oxidative polymerization of biphenyl produces excessive gas and heat, which help to enhance the sensitivities of electric disconnecting devices. In addition, it is also found that the use of biphenyl as an electrolyte additive does not significantly influence the normal performances of the lithium ion batteries. 相似文献
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S. Guhathakurta S. Anandhan Nikhil K. Singha R. N. Chattopadhyay Anil K. Bhowmick 《应用聚合物科学杂志》2006,102(5):4897-4907
Bahera gum, extracted from the bark of Terminalia bellerica, is a waste material. The present study involves the use of this natural gum as a multifunctional additive in natural rubber (NR) and brominated isobutylene‐co‐paramethyl styrene (BIMS). Fourier transform infrared (FTIR) analysis was employed to study the functional groups present in the gum. It was found that fatty acids/esters in the gum act as accelerator activator and can replace stearic acid in rubber formulations. Polyphenols in the gum act as antioxidant and the action is comparable with the commercial antioxidant 2,2,4‐trimethyl‐1,2‐dihydroquinoline (TQ) in natural rubber. The gum improves the tack strength of the rubbers (21% at 2.5 phr loading for NR and 54% at 10 phr loading for BIMS). The gum imparts plasticization effect which is reflected in the reduction in k and enhancement in n values, the exponents in the power law equation, with increasing gum concentration. The activation energy of flow is also reduced with the addition of the gum. Moreover, it decreases the elastic memory of the system which causes reduction in die swell. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4897–4907, 2006 相似文献
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作为润滑添加剂,纳米粒子具有独特的物理化学特性和优良的摩擦学性能。纳米添加剂可以提高基础油的润滑性能,减摩抗磨性能。综述了纳米粒子润滑添加剂的摩擦学特性和润滑机理。目前关于纳米粒子减摩抗磨机理比较一致的观点是纳米粒子在摩擦表面较易吸附且形成润滑保护膜。 相似文献