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1.
合成了2-十二烷硫基-4-苯基-1,3,4-噻二唑-5-硫酮(DBTT),用1H NMR,元素分析,红外光谱技术对其结构进行了表征,用热重分析仪考察了其热稳定性.作为菜籽油(RSO)添加剂,在四球摩擦磨损试验机上测试了其摩擦磨损性能;用扫描电子显微镜观察分析了钢球磨损表面形貌.结果表明:所合成的化合物具有较高的热稳定性,能够提高菜籽油的抗磨减摩性能.  相似文献   

2.
制备了一种含肉桂酸基团的Bola型两亲分子HDC(4-(10-羟基癸氧基)-10-羟基癸氧基肉桂酸酯). 该分子在空气/水界面形成多分子层Langmuir膜结构. 紫外光照可使膜中HDC分子发生光致二聚,也可使HDC与1,16-十六碳二醇形成的混和膜中HDC分子发生二聚. 光照前后膜中分子倾角分别为58.8°和53.2°. 从实验结果推测了分子排列模型,认为HDC分子在LB膜中有序排列,这来源于分子间π-π相互作用和疏水亚甲基链的Z型构象堆积.  相似文献   

3.
Borate esters have good load carrying capacity and lubricating properties. However, borate esters are susceptible to hydrolyzation, which limits their applications. To improve the hydrolysis resistance of borate esters, nitrogen-containing heterocyclic and alkanolamide were introduced into their structures. Two novel multifunctional borate esters were synthesized, and their tribological properties were evaluated in rapeseed oil. The two novel borate esters showed superior tribological properties, as well as excellent anti-rust, anti-corrosion, and anti-oxidant properties. During friction, the mixed film containing B2O3 and nitrogen-containing organic compounds were formed, iron oxide generated on the worn surface, which were important to anti-wear.  相似文献   

4.
X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge spectroscopy (XANES) have been applied to examine the electronic structure of the rare-earth transition-metal oxyarsenides REFeAsO (RE=Ce, Pr, Nd, Sm, Gd) and CeNiAsO. Within the metal-arsenic layer [MAs], the bonding character is predominantly covalent and the As atoms are anionic, as implied by the small energy shifts in the M 2p and As 3d XPS spectra. Within the rare-earth-oxygen layer [REO], the bonding character is predominantly ionic, as implied by the similarity of the O 1s binding energies to those in highly ionic oxides. Substitution with a smaller RE element increases the O 1s binding energy, a result of an enhanced Madelung potential. The Ce 3d XPS and Ce L3-edge XANES spectra have lineshapes and energies that confirm the presence of trivalent cerium in CeFeAsO and CeNiAsO. A population analysis of the valence band spectrum of CeNiAsO supports the formal charge assignment [Ce3+O2−][Ni2+As3−].  相似文献   

5.
Because of the importance in industry, organic Molybdenum compounds have been advanced rapidly in synthesis research and application. The additive foroilsaving is one of organic Molybdenum compounds it is necessary to determine the contents of Molybdenum(Mo), Sulfur(S) and Phosphorus(P) for study of the properties of additives because of antioxygenation of S and recorrodibility and regrindibity of P. Many methods for determination of Mo in additives, such as absorptiometry or differential spetrophometry, have been reported in recent years.  相似文献   

6.
TiO2/聚丙烯酸丁酯纳米复合膜的制备及摩擦性能   总被引:10,自引:0,他引:10  
二氧化钛;TiO2/聚丙烯酸丁酯纳米复合膜的制备及摩擦性能  相似文献   

7.
The interface reactions between transition metal oxide substrates and ultra thin metal layers of different thickness (<15 nm) have been investigated by using x-ray photoelectron spectroscopy (XPS). To a different extent oxidation of deposited metal and reduction of the oxidic substrate is visible for complementary layer systems. For the interface nickel oxide/manganese an enhanced reaction is found compared to the system manganeseoxide/nickel. Based on the experimental data a model of the evolving interface is proposed.  相似文献   

8.
 Synchrotron radiation based spectro-microscopy is shown to be an exciting tool for elemental analysis in the field of heterogeneous interfaces, thin films, and device technology. Results are reported, taken with a spectrometer that enables the combination of a photoemission electron microscope (PEEM) with photoelectron spectroscopies (XPS, UPS) operated at a high brilliance undulator beam line at BESSY. The properties of mc-Si (multi crystalline silicon) are of interest because of their applications in low priced photovoltaic devices. An example of how to analyze the surface potentials of such surfaces without removing the native oxide is given. Tin nano-scale particles are shown to be the decisive factor affecting the corrosion prevention of passivated tinplate surfaces.  相似文献   

9.
X-ray photoelectron spectroscopic (XPS) and X-ray absorption near-edge spectroscopic (XANES) measurements have been made for several series of metal arsenide phosphides MAs1−yPy (M=Co, Fe, Cr) that adopt the MnP-type structure. The P and As XPS binding energies (BEs) and XANES absorption energies of the metal arsenide phosphides do not follow the trend observed for the simple binary phosphides or arsenides, a deviation that arises from the combination of nearest and next-nearest neighbour contributions acting on the P or As photoemission or absorption site. The P 2p3/2 BEs and K-edge absorption energies are lower in MAs1−yPy than in MP because the P atoms are more negatively charged and because the P photoemission or absorption site is screened to a greater extent by less positively charged nearest-neighbour M atoms and more negatively charged next-nearest neighbour P atoms. The As L3- and K-edge absorption energies are higher in MAs1−yPy than in MAs primarily because the As atoms are less negatively charged. The M charge has been evaluated from analysis of the M 2p XPS spectra and the M L- and K-edge XANES spectra.  相似文献   

10.
Water‐based lubricants and metal‐working fluids are becoming more and more popular in modern manufacturing due to environmental concerns. Owing to the poor lubricating properties offered by pure water, additives are generally needed to improve the antiwear and extreme pressure properties. In the present work, the tribological behaviors of synthesized additives in water‐based lubricants are studied for different durations and temperatures by a four‐ball machine, and the worn surfaces were analyzed by scanning electron microscopy (SEM) and X‐ray absorption near‐edge structure (XANES) spectroscopy. It was found that the tribological properties changed with the duration and temperature, and the tribofilms mainly consisted of an adsorbed layer and a tribochemical layer. The compositions of tribofilms also changed with duration and temperature, and the different compositions of tribofilms would result in different tribological properties accordingly. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

11.
聚乙烯醇/半纤维素/纤维素纳米晶复合膜的制备和性能   总被引:1,自引:0,他引:1  
胡宇  孙辉  杨彪  黄斌  徐国志 《高分子学报》2016,(11):1615-1620
通过碱解醇沉法从玉米芯中提取半纤维素,进而采用溶液共混流延法制备出不同比例的聚乙烯醇(PVA)/半纤维素共混膜,在此基础上加入通过硫酸水解脱脂棉制备的纤维素纳米晶(NCC),制备了NCC增强的复合膜.DSC、TGA、FTIR、SEM和薄膜拉伸等研究表明,复合膜的各组分间形成了氢键作用,相容性良好.在PVA/半纤维素共混膜中,半纤维素的加入大幅度提高了复合膜的断裂伸长率:当PVA与半纤维素质量比为3∶1时,复合膜的断裂伸长率高达380%,比纯PVA的140%增加了1.7倍,而拉伸强度仍能保持在较高的水平;纤维素纳米晶的加入,还可改善复合膜的韧性;半纤维素对PVA组分的结晶性能产生了影响,而刚性结构的NCC则对PVA的结晶起抑制作用.此外半纤维素和NCC的引入也提高了复合膜的热性能,使第二阶段分解速率峰的温度提高了约50℃.  相似文献   

12.
《Electroanalysis》2003,15(3):191-195
Electrochemical synthesis of poly(N‐acetylaniline) (PNAANI)/Nafion composite film was carried out by cyclic voltammetry (CV). Its surface morphology, which was evaluated by scanning electron microscopy (SEM), revealed that PNAANI was dispersed into the Nafion film uniformly. X‐ray photoelectron spectrum (XPS) of the composite film was also examined. The electroactivity of the composite film was high in neutral and basic solutions, and the stability of PNAANI/Nafion film in neutral and basic solutions was excellent.  相似文献   

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