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Six new 1,3,4-thiadiazole Schiff base derivatives were synthesized and characterized by IR spectroscopy and ~1H NMR spectrometry, and their anti-corrosion properties and thermal stability were investigated via thermogravimetric analysis(TGA) and copper strip corrosion test. The tribological behavior of the said Schiff base derivatives was evaluated on an Optimol SRV~?4 oscillating reciprocating friction and wear tester. The worn surfaces of the steel discs were investigated using a scanning electron microscope(SEM) and energy dispersive X-ray spectrometer(EDS). The test results indicated that these thiadiazole Schiff base derivatives possessed favourable thermal stability, corrosion inhibiting ability and the capability of improving the tribological characteristic of the base oil effectively. It is assumed that the adsorbed additives probably reacted with the steel surfaces during the friction process, resulting in the formation of a protective film composed of sulphates, sulphides and organic nitrogen compounds. 相似文献
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工程训练实践教学对培养大学的工程综合能力、工程素质和创新能力发挥着重要的作用。以培养大学生工程创新能力为目标,分析现行工程训练创新实践教学过程中存在的问题,剖析产生问题的原因,提出若干解决措施,对提高学生创新能力,培养高素质应用型人才具有促进作用。 相似文献
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INTRODUCTION4 ,4′ Diaminostilbene 2 ,2′ disulfonicacid (DAS)isanimportantintermediatewhichiswidelyusedinsynthesisoffluorescentwhiteningagents ,directdyesandreactivedyes[1,2 ] .Sofar ,theconventionalprocedureusingFeascatalystfortheproductionofDASinChinai… 相似文献
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INTRODUCTION
4,4′-Diaminostilbene-2,2′-disulfonic acid(DAS) is an important intermediate which is widely used in synthesis of fluorescent whitening agents, direct dyes and reactive dyes[1,2].So far, the conventional procedure using Fe as catalyst for the production of DAS in China is greatly limited, due to industrial waste water, high labor intensity and low production capability. The electrochemical reduction method has been reported[3] overseas, but it is not suitable for China considering its large equipment investment, lower yield and great power consumption. Compared with the methods mentioned above, the catalytic hydrogenation method has attracted a great deal of attention in view of its simple and easy operation, high production capacity and high production efficiency[4-6].The relatively cheap Raney nickel is not used here since it shows a low safety performance in preparing DAS at a high reaction temperature and high pressure. In this paper, highly reactive and recyclable palladium-carbon is chosen as the catalyst. DAS of high purity and high yield is prepared under mild conditions. The catalytic hydrogenation method is a prospective method in producing DAS. 相似文献
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