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从分子设计的观点出发,合成了一种新型含硼杂环抗磨添加剂SONB,采用四球摩擦磨损试验机评价了其摩擦学性能。结果表明,在菜籽油(RSO)中加入添加剂SONB后,承载能力有较大提高,磨斑直径明显减小,摩擦系数明显降低。从磨损表面SEM/EDS、XPS分析结果可以推断,该添加剂在摩擦过程中发生了化学分解反应,S元素在钢球的表面形成了一层含Fe2(SO4)3和FeS2 的反应膜,N、B元素则以吸附膜的形式存在于摩擦表面, 两种膜的协同作用提高了菜籽油的减摩抗磨性能及承载能力。 相似文献
74.
The dehydration behaviors of two different hydrated zinc borate species, Zn[B3O3(OH)5] · H2O and Zn[B3O4(OH)3], which are industrially important flame retardants, were studied by thermal gravimetric(TG) analysis and in situ diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. Dehydration onset temperatures of Zn[B3O3(OH)5] · H2O and Zn[B3O4(OH)3] were 129 and 320°C, respectively, at a 10°C/min ramp rate. A very small amount of boric acid was volatilized in addition to water vapor when both samples were heated at 250°C. A significant amount of water vapor was adsorbed by Zn[B3O3(OH)5] · H2O from air at 25°C. However, Zn[B3O4(OH)3] adsorbed a very small amount of water under the same conditions. Both zinc borates did not have a tendency to cake during storage. 相似文献
75.
硼酸盐润滑油添加剂的发展动态 总被引:13,自引:2,他引:11
简要地阐述了硼酸盐润滑油加剂的发展现状和研究动态,对其多种制备方法进行了比较和总结,并重点对其性能和作用机理的研究进行了分析和归纳,特别强调指出,改善硼酸盐润滑油添加剂的储存稳定性和抗乳化性,研究其与含磷,硫,氮等活性元素添加剂的复配规律以及复配作用机理,是这一领域的主要趋势之一。 相似文献
76.
The present study investigated the role of endogenous opioids in the expression of defensive behaviors (DBs) and the suppression of cell proliferation (CP) in the dentate gyrus (DG) induced by exposure to predator odor, trimethyl thiazoline (TMT). Adult male rats were injected with either naltrexone (an opioid antagonist, 5 mg/kg) or saline 30 min before exposure to either TMT or a control odor. Behavior was scored for the first 15 min of odor exposure. Bromodeoxyuridine (BrdU, 200 mg/kg) was then injected, and the rats were perfused 1 hr later. Exposure to TMT increased the expression of DBs and suppressed the number of proliferating cells in the DG. Pretreatment with naltrexone attenuated the effects of TMT on DB expression but did not attenuate the effects of TMT on CP. In addition, naltrexone administration suppressed CP in the absence of TMT. These results demonstrate a dissociation between DBs and regulation of CP in the DG. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
纳米硼酸铜的表征与在水介质中的摩擦学性能 总被引:2,自引:2,他引:0
采用透射电子显微镜(TEM)、X射线衍射(XRD)和红外光谱(IR)对油酸钠修饰硼酸铜纳米颗粒的形貌、物相和表面结构进行了表征,制备的硼酸铜纳米粒子粒径为60~90 nm,并能在水中均匀分散。用四球试验机考察了硼酸铜纳米粒子在水介质中的摩擦学性能及用扫描电子显微镜(SEM)观察了摩斑表面形貌。结果表明,添加质量分数为0.1% 2.5%的油酸钠修饰硼酸铜纳米粒子,可使水的承载能力显著提高,抗磨减摩性能也有较大提高。用X射线光电子能谱(XPS)分析了蚀球磨斑表面的化学成分,在摩擦副表面检测出Cu,B,Fe等的氧化物,硼酸铜纳米粒子沉积在摩擦表面上以及生成的氧化物保护膜起良好的抗磨减摩作用。 相似文献
78.
Mustafa Usta Derya Ustaomer Saip Nami Kartal Sedat Ondaral 《International journal of molecular sciences》2009,10(6):2789-2797
In this study, the effects of various boron compounds on the termite resistance of MDF panels were evaluated. Either borax (BX), boric acid (BA), zinc borate (ZB), or sodium perborate tetrahydrate (SPT) were added to urea-formaldehyde (UF) resin at target contents of 1%, 1.5%, 2% and 2.5% based on dry fiber weight. The panels were then manufactured using 12% urea-formaldehyde resin and 1% NH4Cl. MDF samples from the panels were tested against the subterranean termites, Coptotermes formosanus Shiraki. Laboratory termite resistance tests showed that all samples containing boron compounds had greater resistance against termite attack compared to untreated MDF samples. At the second and third weeks of exposure, nearly 100% termite mortalities were recorded in all boron compound treated samples. The highest termite mortalities were determined in the samples with either BA or BX. Also, it was found that SPT showed notable performance on the termite mortality. As chemical loadings increased, termite mortalities increased, and at the same time the weight losses of the samples decreased. 相似文献
79.
Reaction of CrCl3(THF)3 with K[HB(pz)3] in THF leads to the formation of the complex K[CrCl3{HB(pz)3}] (1). The salt metathesis of complex 1 with [Ph4P]Br in CH2Cl2 yields the complex [Ph4P][CrCl3{HB(pz)3}](2). The structure of complex 2 · CHCl3 has been determined by single crystal X-ray diffraction. In the anion the metal centre shows a distorted octahedral geometry with the hydrotris(1-pyrazolyl)borate bonded as N,N′,N″-donor tripod ligand and three chloride atoms completing the co-ordination sphere. Complex 2 in the presence of MAO leads to the formation of an active catalyst for the polymerization of ethylene. 相似文献
80.