Michael addition of nitroalkanes to α,β-unsaturated carbonyl compounds occurs in the presence of KF/AI_2O_3/PEG4000 without solvent.Yields are fair to good and work-ups are easy.
The objective of this research was to show a way to conduct rejuvenation of aged polymer modified asphalt binder（PMB） successfully.To fully evaluate and understand the rejuvenation of aged PMB,the Penetration grade ...The objective of this research was to show a way to conduct rejuvenation of aged polymer modified asphalt binder（PMB） successfully.To fully evaluate and understand the rejuvenation of aged PMB,the Penetration grade tests including penetration,soften point,ductility and elastic recovery and SuperpaveTM PG grade tests including DSR,BBR and DDT were conducted.The rejuvenation effect of aged PMB by utilizing a fluid recycling agent in common use for binder rejuvenation was evaluated.And then the compound rejuvenation effect of aged PMB by utilizing the recycling agent with a new modifying additive for binder modification was evaluated.The experimental results indicated that the recycling agent in common use currently does not apply to polymer modified asphalt binder rejuvenation.But the recycling agent together with the modifying additive can restore the characteristics of aged polymer modified binder very well.Therefore,compound rejuvenation of polymer modified asphalt binder is recommended.展开更多
The synthesis of amphiphilic aggregation-induced emission （ALE） dyes based organic nanoparticles has recently attracted in- creasing attention in the biomedical fields. These AlE dyes based nanoparticles could effec...The synthesis of amphiphilic aggregation-induced emission （ALE） dyes based organic nanoparticles has recently attracted in- creasing attention in the biomedical fields. These AlE dyes based nanoparticles could effectively overcome the aggregation caused quenching effect of conventional organic dyes, making them promising candidates for fabrication of ultrabright organic luminescent nanomaterials. In this work, AIE-active luminescent polymeric nanoparticles （4-NH2-PEG-TPE-E LPNs） were facilely fabricated through Michael addition reaction between tetraphenylethene acrylate （TPE-E） and 4-arm-poly（ethylene glycol）-amine （4-NH2-PEG） in rather mild ambient. The 4-NH2-PEG can not only endow these AlE-active LPNs good water dispersibility, but also provide functional groups for further conjugation reaction. The size, morphology and luminescent prop- erties of 4-NH2-PEG-TPE-E LPNs were characterized by a series of techniques in detail. Results suggested that these AlE-active LPNs showed spherical morphology with diameter about 100-200 nm. The obtained 4-NH2-PEG-TPE-E LPNs display high water dispersibility and strong fluorescence intensity because of their self assembly and AlE properties of TPE-E. Biological evaluation results demonstrated that 4-NH2-PEG-TPE-E LPNs showed negative toxicity toward cancer cells and good fluorescent imaging performance. All of these features make 4-NHz-PEG-TPE-E LPNs promising candidates for biolog- ical imaging and therapeutic applications.展开更多
The astonishingly distinct lubricity difference between the ionic liquid modified carbon nanoparticles grafted by anion and cation moieties(A-g-CNPs and C-g-CNPs)was well established as additives of polyethylene glyco...The astonishingly distinct lubricity difference between the ionic liquid modified carbon nanoparticles grafted by anion and cation moieties(A-g-CNPs and C-g-CNPs)was well established as additives of polyethylene glycol(PEG200).The peripheral anion moieties and positively charged inner parts of C-g-CNPs could successively absorb onto the friction interfaces by electrostatic interactions to form the organic-inorganic electric double layer structures,tremendously boosting the lubricity of PEG200.Contrarily,the preferentially electrostatic adsorption of negatively charged inner parts but repulsion of the peripheral cation moieties determined the weak embedded stability of A-g-CNPs between the friction interfaces,even impairing the lubricity of PEG200.This work can offer solidly experimental and theoretical guidance for designing and developing the high-performance nanoadditives modified by ionic molecules.展开更多
文摘Michael addition of nitroalkanes to α,β-unsaturated carbonyl compounds occurs in the presence of KF/AI_2O_3/PEG4000 without solvent.Yields are fair to good and work-ups are easy.
基金Funded in Part by the National Natural Science Foundation of China (No. 50878054)
文摘The objective of this research was to show a way to conduct rejuvenation of aged polymer modified asphalt binder（PMB） successfully.To fully evaluate and understand the rejuvenation of aged PMB,the Penetration grade tests including penetration,soften point,ductility and elastic recovery and SuperpaveTM PG grade tests including DSR,BBR and DDT were conducted.The rejuvenation effect of aged PMB by utilizing a fluid recycling agent in common use for binder rejuvenation was evaluated.And then the compound rejuvenation effect of aged PMB by utilizing the recycling agent with a new modifying additive for binder modification was evaluated.The experimental results indicated that the recycling agent in common use currently does not apply to polymer modified asphalt binder rejuvenation.But the recycling agent together with the modifying additive can restore the characteristics of aged polymer modified binder very well.Therefore,compound rejuvenation of polymer modified asphalt binder is recommended.
基金supported by the National Natural Science Foundation of China (21134004, 21201108, 51363016, 21474057, 21564006, 21561022)the National Basic Research Program (2011CB935700)
文摘The synthesis of amphiphilic aggregation-induced emission （ALE） dyes based organic nanoparticles has recently attracted in- creasing attention in the biomedical fields. These AlE dyes based nanoparticles could effectively overcome the aggregation caused quenching effect of conventional organic dyes, making them promising candidates for fabrication of ultrabright organic luminescent nanomaterials. In this work, AIE-active luminescent polymeric nanoparticles （4-NH2-PEG-TPE-E LPNs） were facilely fabricated through Michael addition reaction between tetraphenylethene acrylate （TPE-E） and 4-arm-poly（ethylene glycol）-amine （4-NH2-PEG） in rather mild ambient. The 4-NH2-PEG can not only endow these AlE-active LPNs good water dispersibility, but also provide functional groups for further conjugation reaction. The size, morphology and luminescent prop- erties of 4-NH2-PEG-TPE-E LPNs were characterized by a series of techniques in detail. Results suggested that these AlE-active LPNs showed spherical morphology with diameter about 100-200 nm. The obtained 4-NH2-PEG-TPE-E LPNs display high water dispersibility and strong fluorescence intensity because of their self assembly and AlE properties of TPE-E. Biological evaluation results demonstrated that 4-NH2-PEG-TPE-E LPNs showed negative toxicity toward cancer cells and good fluorescent imaging performance. All of these features make 4-NHz-PEG-TPE-E LPNs promising candidates for biolog- ical imaging and therapeutic applications.
基金financially supported by the National Natural Science Foundation of China(No.51975493).
文摘The astonishingly distinct lubricity difference between the ionic liquid modified carbon nanoparticles grafted by anion and cation moieties(A-g-CNPs and C-g-CNPs)was well established as additives of polyethylene glycol(PEG200).The peripheral anion moieties and positively charged inner parts of C-g-CNPs could successively absorb onto the friction interfaces by electrostatic interactions to form the organic-inorganic electric double layer structures,tremendously boosting the lubricity of PEG200.Contrarily,the preferentially electrostatic adsorption of negatively charged inner parts but repulsion of the peripheral cation moieties determined the weak embedded stability of A-g-CNPs between the friction interfaces,even impairing the lubricity of PEG200.This work can offer solidly experimental and theoretical guidance for designing and developing the high-performance nanoadditives modified by ionic molecules.
