The influence of pressure on miscibility behavior of the systems polystyrene/cyclopentan(?)and polystyrene/1-phenyldecane is studied with a modified hole theory.It is found that the pres-sure dependence of excess volu...The influence of pressure on miscibility behavior of the systems polystyrene/cyclopentan(?)and polystyrene/1-phenyldecane is studied with a modified hole theory.It is found that the pres-sure dependence of excess volume is responsible for the different kinds of behavior of these two sys-tems.Furthermore,the excess volume is decomposed into two separatc parts,one from the contri-bution of cell volume expansion and the other from the change of hole fraction,and their relation-ship with pressure dependence of the miscibility behavior is analysed.展开更多
Developing functional additive resistant to space atomic oxygen(AO)irradiation through simple molecular design and chemical synthesis to enhance the lubricating performance of multialkylated cyclopentanes(MACs)oil is ...Developing functional additive resistant to space atomic oxygen(AO)irradiation through simple molecular design and chemical synthesis to enhance the lubricating performance of multialkylated cyclopentanes(MACs)oil is a significant challenge.Herein,sulfur-containing polyhedral oligomere silsesquioxane(POSS)were synthesize via a click-chemistry reaction of octavinyl polyhedral oligomeric with alkyl sulfide.The reduce-friction(RF),anti-wear(AW)properties and anti-AO irradiation of POSS-S-R as MACs base oil additives in atmospheric and simulated space environments were systematically investigated for the first time.Results demonstrate that POSS-S-R not only possesses outstanding anti-AO irradiation capacity but also effectively improves the RF and AW of MACs in atmospheric or simulated space surroundings.This improvement is due to the excellent anti-AO irradiation properties of the POSS structure itself and the high load-carrying ability of silicon-containing and sulfur-containing compounds generated by tribo-chemical reactions,which effectively separates the direct contact of the friction interface.We believe that this synthesized POSS-S-R is a promising additive for space lubricants.展开更多
Two lithium-based ionic liquids(ILs,L-C3N3,and L-P3N3)were synthesized and evaluated as novel lubricant additives for multiply alkylated cyclopentanes(MACs).They were found to be approximately 1.0%soluble in MACs at r...Two lithium-based ionic liquids(ILs,L-C3N3,and L-P3N3)were synthesized and evaluated as novel lubricant additives for multiply alkylated cyclopentanes(MACs).They were found to be approximately 1.0%soluble in MACs at room temperature(RT),whereas traditional ILs,such as 1-ethyl-3-methylimidazolium tetrafluoroborate(L-B102),1-hexyl-3-methylimidazolium hexafluorophosphate(L-P106),and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(L-F102),could not be dissolved in this base oil.Friction tests indicated that these ILs exhibit excellent friction-reducing and anti-wear properties both at RT and at 100°C.They can improve the tribological properties of MACs at RT to a greater extent than the commonly used lubricant zinc dialkyldithiophosphate(T204),even at a concentration of 0.1%.The load ramp test showed that MACs with L-C3N3 and L-P3N3 also exhibit high load-carrying capabilities.Scanning electron microscope(SEM)and X-ray photoelectron spectrometer(XPS)results indicated that physical adsorption and complex tribochemical reactions occurred between the ILs and metal surfaces during the sliding process,thereby forming a surface protective film that significantly contributed to the excellent tribological properties of the new ILs.展开更多
Adsorption, diffusion and thermal desorption features of cyclopentane and cyclohexane in silicalite-1 have been investigated using the intelligent gravimetric technique. Both the saturation adsorption loadings and dif...Adsorption, diffusion and thermal desorption features of cyclopentane and cyclohexane in silicalite-1 have been investigated using the intelligent gravimetric technique. Both the saturation adsorption loadings and diffusion coefficient of cyclopentane were greater than those of cyclohexane. The diffusivity of cyclopentane was about one order of magnitude greater than that of cyclohexane at the same temperature and initial loading. For cyclopentane, there was only one kind of desorption process at adsorption loadings lower than 4 muc (molecule per unit cell), but two desorption processes appeared at the adsorption loadings higher than 4 muc. While for cyclohexane, one desorption process was found in the whole range of loadings. Both thermal desorption peaks of cyclopentane and cyclohexane moved to higher temperature region with increasing loading.展开更多
The effect of additives (anionic surfactant sodium dodecyl sulfate (SDS), nonionic surfactant alkyl polysaccharide glycoside (APG), and liquid hydrocarbon cyclopentane (CP)) on hydrate induction time and formation rat...The effect of additives (anionic surfactant sodium dodecyl sulfate (SDS), nonionic surfactant alkyl polysaccharide glycoside (APG), and liquid hydrocarbon cyclopentane (CP)) on hydrate induction time and formation rate, and storage capacity was studied in this work. Micelle surfactant solutions were found to reduce hydrate induction time, increase methane hydrate formation rate and improve methane storage capacity in hydrates. In the presence of surfactant, hydrate could form quickly in a quiescent system and the energy costs of hydrate formation were reduced. The critical micelle concentrations of SDS and APG water solutions were found to be 300×10-6 and 500×10-6 for methane hydrate formation system respectively. The effect of anionic surfactant (SDS) on methane storage in hydrates is more pronounced compared to a nonionic surfactant (APG). CP also reduced hydrate induction time and improved hydrate formation rate, but could not improve methane storage in hydrates.展开更多
Asymmetric hydrogenation of tetrasubstituted alkenes is an important but challenging research topic.Herein,we report an efficient iridium-catalyzed asymmetric hydrogenation of tetrasubstituted α,β-unsaturated ketone...Asymmetric hydrogenation of tetrasubstituted alkenes is an important but challenging research topic.Herein,we report an efficient iridium-catalyzed asymmetric hydrogenation of tetrasubstituted α,β-unsaturated ketones for the synthesis of chiral 2-substituted cyclopentyl aryl ketones,an important chiral structural motif for the preparation of chiral pharmaceuticals and bioactive molecules.The reaction proceeded very well with good functional group compatibility and delivered the hydrogenated products in high yields and stereoselectivities(up to 99% yield,>20:1 dr and 99%ee).In addition,the reaction could be carried out on a gram-scale,and all four stereoisomers of the hydrogenated products bearing two contiguous stereocenters were obtained.Furthermore,the hydrogenated product can be transformed into the ERβ agonist Erteberel,and the reaction pathway was also studied via deuterium-labelling experiments.展开更多
In this paper,we fabricate a biomimetic superhydrophobic coating on an X90 pipeline steel substrate by electrodeposition of copper,hydrothermal treatment to form a copper oxide layer,and subsequent surface modificatio...In this paper,we fabricate a biomimetic superhydrophobic coating on an X90 pipeline steel substrate by electrodeposition of copper,hydrothermal treatment to form a copper oxide layer,and subsequent surface modification with Stearic Acid(SA).The coating exhibits static contact angles of water of 160°±-3.1°in the air and 170.7°±2.5°in cyclopentane,indicating the strongly water-repelling nature of the coating.The morphologies of the cyclopentane hydrate formed on steel substrates with and without the superhydrophobic coating are investigated.The results show that the hydrate particle on the coating exhibits spherical morphology and herein the interfacial contact area and adhesion force to the solid surface can be essentially reduced.The adhesion force reduction may be resulted by the decrease in the contact area between the hydrate and the solid surface.展开更多
In the present study,the thermodynamic and economic performance of a combined thermodynamic cycle formed by an ORC and a Kalina cycle,which can simultaneously recover waste heat of exhaust gas and cooling water of mar...In the present study,the thermodynamic and economic performance of a combined thermodynamic cycle formed by an ORC and a Kalina cycle,which can simultaneously recover waste heat of exhaust gas and cooling water of marine engine,has been analyzed.Two typical marine engines are selected to be the waste heat source.Six economic indicators are used to analyze the economic performance of this combined thermodynamic cycle system with different marine engine load and under practical comprehensive operating condition of marine engine.The results of the present study show that the combined thermodynamic cycle system with R123 as organic working fluid has the best performance.The system with cis-butene has the worst economic performance.Under practical comprehensive operating conditions of ships,R123 has the shortest Payback Periods,which are 8.51 years and 8.14 years for 8 S70 ME-C10.5 engine and 5G95 ME-C10.5 engine,respectively.Correspondingly,payback Periods of Cyclopentane are 11.95 years and 11.90 years.The above values are much shorter than 25 years which are the lifetime of a marine ship.Under practical comprehensive operating conditions of ships,the combined cycle system can provide output power which is at least equivalent to 25%of engine power.Considering that R123 will be phased out in near future,cyclopentane may be its good successor.Cyclopentane can be used safely by correct handling and installing according to manufacturer's instructions.展开更多
文摘The influence of pressure on miscibility behavior of the systems polystyrene/cyclopentan(?)and polystyrene/1-phenyldecane is studied with a modified hole theory.It is found that the pres-sure dependence of excess volume is responsible for the different kinds of behavior of these two sys-tems.Furthermore,the excess volume is decomposed into two separatc parts,one from the contri-bution of cell volume expansion and the other from the change of hole fraction,and their relation-ship with pressure dependence of the miscibility behavior is analysed.
基金support from National Key Research and Development Program of China(2021YFA0716304)National Natural Science Foundation of China(52075524,51705504 and 21972153)+3 种基金Youth Innovation Promotion Association CAS(2022429 and 2018454)Gansu Province Science and Technology Plan(22JR5RA094,20JR10RA060)Natural Science Foundation of Shandong Province(ZR2022ZD09)LICP Cooperation Foundation for Young Scholars(HZJJ21-06).
文摘Developing functional additive resistant to space atomic oxygen(AO)irradiation through simple molecular design and chemical synthesis to enhance the lubricating performance of multialkylated cyclopentanes(MACs)oil is a significant challenge.Herein,sulfur-containing polyhedral oligomere silsesquioxane(POSS)were synthesize via a click-chemistry reaction of octavinyl polyhedral oligomeric with alkyl sulfide.The reduce-friction(RF),anti-wear(AW)properties and anti-AO irradiation of POSS-S-R as MACs base oil additives in atmospheric and simulated space environments were systematically investigated for the first time.Results demonstrate that POSS-S-R not only possesses outstanding anti-AO irradiation capacity but also effectively improves the RF and AW of MACs in atmospheric or simulated space surroundings.This improvement is due to the excellent anti-AO irradiation properties of the POSS structure itself and the high load-carrying ability of silicon-containing and sulfur-containing compounds generated by tribo-chemical reactions,which effectively separates the direct contact of the friction interface.We believe that this synthesized POSS-S-R is a promising additive for space lubricants.
基金The National Natural Science Foundation of China(NSFC)(Nos.51105353,51175492,and 21173243)The National Key Basic Research and Development(973)Program of China project(2013CB632300).
文摘Two lithium-based ionic liquids(ILs,L-C3N3,and L-P3N3)were synthesized and evaluated as novel lubricant additives for multiply alkylated cyclopentanes(MACs).They were found to be approximately 1.0%soluble in MACs at room temperature(RT),whereas traditional ILs,such as 1-ethyl-3-methylimidazolium tetrafluoroborate(L-B102),1-hexyl-3-methylimidazolium hexafluorophosphate(L-P106),and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(L-F102),could not be dissolved in this base oil.Friction tests indicated that these ILs exhibit excellent friction-reducing and anti-wear properties both at RT and at 100°C.They can improve the tribological properties of MACs at RT to a greater extent than the commonly used lubricant zinc dialkyldithiophosphate(T204),even at a concentration of 0.1%.The load ramp test showed that MACs with L-C3N3 and L-P3N3 also exhibit high load-carrying capabilities.Scanning electron microscope(SEM)and X-ray photoelectron spectrometer(XPS)results indicated that physical adsorption and complex tribochemical reactions occurred between the ILs and metal surfaces during the sliding process,thereby forming a surface protective film that significantly contributed to the excellent tribological properties of the new ILs.
文摘Adsorption, diffusion and thermal desorption features of cyclopentane and cyclohexane in silicalite-1 have been investigated using the intelligent gravimetric technique. Both the saturation adsorption loadings and diffusion coefficient of cyclopentane were greater than those of cyclohexane. The diffusivity of cyclopentane was about one order of magnitude greater than that of cyclohexane at the same temperature and initial loading. For cyclopentane, there was only one kind of desorption process at adsorption loadings lower than 4 muc (molecule per unit cell), but two desorption processes appeared at the adsorption loadings higher than 4 muc. While for cyclohexane, one desorption process was found in the whole range of loadings. Both thermal desorption peaks of cyclopentane and cyclohexane moved to higher temperature region with increasing loading.
基金Chinese Jiangsu Province Education Committee Program (G0109199)Chinese Natural Science Foundation (50176051).
文摘The effect of additives (anionic surfactant sodium dodecyl sulfate (SDS), nonionic surfactant alkyl polysaccharide glycoside (APG), and liquid hydrocarbon cyclopentane (CP)) on hydrate induction time and formation rate, and storage capacity was studied in this work. Micelle surfactant solutions were found to reduce hydrate induction time, increase methane hydrate formation rate and improve methane storage capacity in hydrates. In the presence of surfactant, hydrate could form quickly in a quiescent system and the energy costs of hydrate formation were reduced. The critical micelle concentrations of SDS and APG water solutions were found to be 300×10-6 and 500×10-6 for methane hydrate formation system respectively. The effect of anionic surfactant (SDS) on methane storage in hydrates is more pronounced compared to a nonionic surfactant (APG). CP also reduced hydrate induction time and improved hydrate formation rate, but could not improve methane storage in hydrates.
基金supported by the National Key R&D Program of China(No.2018YFE0126800)the National Natural Science Foundation of China(Nos.21991112 and 22001164)the Shanghai Pujiang Program(20PJ1406400).
文摘Asymmetric hydrogenation of tetrasubstituted alkenes is an important but challenging research topic.Herein,we report an efficient iridium-catalyzed asymmetric hydrogenation of tetrasubstituted α,β-unsaturated ketones for the synthesis of chiral 2-substituted cyclopentyl aryl ketones,an important chiral structural motif for the preparation of chiral pharmaceuticals and bioactive molecules.The reaction proceeded very well with good functional group compatibility and delivered the hydrogenated products in high yields and stereoselectivities(up to 99% yield,>20:1 dr and 99%ee).In addition,the reaction could be carried out on a gram-scale,and all four stereoisomers of the hydrogenated products bearing two contiguous stereocenters were obtained.Furthermore,the hydrogenated product can be transformed into the ERβ agonist Erteberel,and the reaction pathway was also studied via deuterium-labelling experiments.
基金supported by the National Natural Science Foundation of China(Grant Nos.51704316 and 51974252)the Natural Science Basic Research Plan in Shaanxi Province of China(Program No.2020JQ-775)+3 种基金Scientific Research Program of Shaanxi Provincial Education Department(18JC025),ChinaShaanxi Provincial Key Research and Development Program(2019ZDLGY06-03),ChinaScience and Technology Program of Xi’an,China(No.2019217914GXRC015CG016-GXYD15.4)Scientific Research Program Funded by Shaanxi Provincial Education Department(19JK0658).
文摘In this paper,we fabricate a biomimetic superhydrophobic coating on an X90 pipeline steel substrate by electrodeposition of copper,hydrothermal treatment to form a copper oxide layer,and subsequent surface modification with Stearic Acid(SA).The coating exhibits static contact angles of water of 160°±-3.1°in the air and 170.7°±2.5°in cyclopentane,indicating the strongly water-repelling nature of the coating.The morphologies of the cyclopentane hydrate formed on steel substrates with and without the superhydrophobic coating are investigated.The results show that the hydrate particle on the coating exhibits spherical morphology and herein the interfacial contact area and adhesion force to the solid surface can be essentially reduced.The adhesion force reduction may be resulted by the decrease in the contact area between the hydrate and the solid surface.
基金funded by the National Natural Science Foundation of China(Grant No.51506001)Beijing Municipal Education Commission(KM201710005029)。
文摘In the present study,the thermodynamic and economic performance of a combined thermodynamic cycle formed by an ORC and a Kalina cycle,which can simultaneously recover waste heat of exhaust gas and cooling water of marine engine,has been analyzed.Two typical marine engines are selected to be the waste heat source.Six economic indicators are used to analyze the economic performance of this combined thermodynamic cycle system with different marine engine load and under practical comprehensive operating condition of marine engine.The results of the present study show that the combined thermodynamic cycle system with R123 as organic working fluid has the best performance.The system with cis-butene has the worst economic performance.Under practical comprehensive operating conditions of ships,R123 has the shortest Payback Periods,which are 8.51 years and 8.14 years for 8 S70 ME-C10.5 engine and 5G95 ME-C10.5 engine,respectively.Correspondingly,payback Periods of Cyclopentane are 11.95 years and 11.90 years.The above values are much shorter than 25 years which are the lifetime of a marine ship.Under practical comprehensive operating conditions of ships,the combined cycle system can provide output power which is at least equivalent to 25%of engine power.Considering that R123 will be phased out in near future,cyclopentane may be its good successor.Cyclopentane can be used safely by correct handling and installing according to manufacturer's instructions.