A series of high performance lubricants of water-soluble polymers with telechelic or star structures has been studied. Their average molecular weights (M) over bar are 1800-6000. The chemical structures of the lubrica...A series of high performance lubricants of water-soluble polymers with telechelic or star structures has been studied. Their average molecular weights (M) over bar are 1800-6000. The chemical structures of the lubricants are characterized by their hydrophilic groups (-CH2CH2O-), -COOH, -OH, -CONH2 and antiwear active elements (S,P,Zn and Mo). The results of assessing for the anti-wear property indicate that this kind of water-soluble polymeric lubricants possesses excellent watersolubility, lubricity and anti-wear property. A preliminary study on the anti-wear mechanism of the polymers is performed by means of electron probe and scanning electron microscopy (SEM).展开更多
The reaction of 5, 10, 15, 20-tetra-(4-pyridyl) porphyrin 1 with triruthenium dodecacarbonyl [Ru3(CO)12], zinc(II) acetate, copper(II) acetate, cobalt(II) acetate afforded complexes 2a?2d respectively. Treatment of 2a...The reaction of 5, 10, 15, 20-tetra-(4-pyridyl) porphyrin 1 with triruthenium dodecacarbonyl [Ru3(CO)12], zinc(II) acetate, copper(II) acetate, cobalt(II) acetate afforded complexes 2a?2d respectively. Treatment of 2a?2d with Merrifield’s peptide resin obtained 3a?3d. The compounds 3a?3d reacted with methyl iodide respectively gave 4a?4d. New complexes 4a?4d have been identified by IR, UV-visible spectra, and AES.展开更多
Efficient and sustainable use of water-based lubricants is essential for energy efficiency.Therefore,the use of water-lubricated mechanical systems instead of conventional oil lubricants is extremely attractive from t...Efficient and sustainable use of water-based lubricants is essential for energy efficiency.Therefore,the use of water-lubricated mechanical systems instead of conventional oil lubricants is extremely attractive from the viewpoint of resource conservation.In this study,water-soluble Cu nanoparticles of size approximately 3 nm were prepared at room temperature(around 25 °C) via in-situ surface modification.The tribological behavior of the as-synthesized Cu nanoparticles as an additive in distilled water was evaluated using a universal micro-tribotester.The results show that the as-synthesized Cu nanoparticles,as a water-based lubricant additive,can significantly improve the tribological properties of distilled water.In particular,the lowest friction coefficient of 0.06 was obtained via lubrication with a concentration of 0.6 wt% of Cu nanoparticles in distilled water,which is a reduction of 80.6% compared with that obtained via lubrication with distilled water alone.It is considered that some Cu nanoparticles entered the contact area of the friction pairs to form a complex lubricating film and prevent direct contact of the friction pairs.Furthermore,some Cu nanoparticles in the solution accelerate the heat transfer process,which also results in good tribological properties.展开更多
基金This study is supported by the National Natural Science Foundation of China
文摘A series of high performance lubricants of water-soluble polymers with telechelic or star structures has been studied. Their average molecular weights (M) over bar are 1800-6000. The chemical structures of the lubricants are characterized by their hydrophilic groups (-CH2CH2O-), -COOH, -OH, -CONH2 and antiwear active elements (S,P,Zn and Mo). The results of assessing for the anti-wear property indicate that this kind of water-soluble polymeric lubricants possesses excellent watersolubility, lubricity and anti-wear property. A preliminary study on the anti-wear mechanism of the polymers is performed by means of electron probe and scanning electron microscopy (SEM).
文摘The reaction of 5, 10, 15, 20-tetra-(4-pyridyl) porphyrin 1 with triruthenium dodecacarbonyl [Ru3(CO)12], zinc(II) acetate, copper(II) acetate, cobalt(II) acetate afforded complexes 2a?2d respectively. Treatment of 2a?2d with Merrifield’s peptide resin obtained 3a?3d. The compounds 3a?3d reacted with methyl iodide respectively gave 4a?4d. New complexes 4a?4d have been identified by IR, UV-visible spectra, and AES.
基金the financial support provided by the Ministry of Science and Technology of China(project of “973” Plan,grant No.2013CB632303)National Natural Science Foundation of China(grant Nos.51405132,21671053 and 51605143)
文摘Efficient and sustainable use of water-based lubricants is essential for energy efficiency.Therefore,the use of water-lubricated mechanical systems instead of conventional oil lubricants is extremely attractive from the viewpoint of resource conservation.In this study,water-soluble Cu nanoparticles of size approximately 3 nm were prepared at room temperature(around 25 °C) via in-situ surface modification.The tribological behavior of the as-synthesized Cu nanoparticles as an additive in distilled water was evaluated using a universal micro-tribotester.The results show that the as-synthesized Cu nanoparticles,as a water-based lubricant additive,can significantly improve the tribological properties of distilled water.In particular,the lowest friction coefficient of 0.06 was obtained via lubrication with a concentration of 0.6 wt% of Cu nanoparticles in distilled water,which is a reduction of 80.6% compared with that obtained via lubrication with distilled water alone.It is considered that some Cu nanoparticles entered the contact area of the friction pairs to form a complex lubricating film and prevent direct contact of the friction pairs.Furthermore,some Cu nanoparticles in the solution accelerate the heat transfer process,which also results in good tribological properties.
