Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcell...Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcellulose （EC） by the emulsion solvent diffusion technique. The release rate of mefformin from the microcapsules was highly dependent on the encapsulating formulation, thus being used as an index for formulation screening. Orthogonal experiments were performed to optimize the coating formulation. Results The final chosen formulation for coating of mefformin microcapsules were as follows： （ 1 ） the ratio of EC （20cps） to EC （45cps） was 50：50; （2） the ratio of plasticizer to coating materials was 20% ;and （3） the ratio of resin-mefformin complexes to coating materials was 5 ： 1. Conclusion The prolonged release microspheres of mefformin hydrochloride were successfully prepared.展开更多
This paper applies the Debye-Hückel-Onsager electrolyte solution theory to investigate the diffusivity of ions in concrete pore solutions.First,a model of the diffusion coefficient associated with the ionic speci...This paper applies the Debye-Hückel-Onsager electrolyte solution theory to investigate the diffusivity of ions in concrete pore solutions.First,a model of the diffusion coefficient associated with the ionic species,solution concentration and ambient temperature is proposed in the saturated concrete.Secondly,as an example,the effects of sodium chloride solution concentration,which are associated with influencing factors such as the ionic cloud radius,electrophoresis and relaxation,on the chloride diffusion coefficient are analyzed.It is found that the diffusion coefficient decreases with the increase in solution concentration,and the electrophoresis and ionic cloud radius are two important factors influencing the ionic diffusivity.Finally,the experiments,in which the chloride diffusion coefficients in specimens under different water-cement ratios are measured by the rapid chloride migration（RCM）method,are carried out to validate the effectiveness of the proposed model,and the results indicate that there is a generally reasonable agreement between the experimental and the proposed model results.展开更多
Solar evaporation based on plasmonic metal nanoparticles(MNPs)is emerging as a promising technology.However,the fine structure of MNPs is unstable,and both the high temperature generated by intensive light and corrosi...Solar evaporation based on plasmonic metal nanoparticles(MNPs)is emerging as a promising technology.However,the fine structure of MNPs is unstable,and both the high temperature generated by intensive light and corrosive ions in water could damage them.The performance will decline after recycling and long-time usage.To address these issues,we adopted a sponge-templating method for preparing sandwich-like nanoplates with the gold nanoparticles(Au NPs)confined in reduced graphene oxide(rGO)nanosheets.Due to the confinement effect,both the surface melting and ion diffusion were suppressed.The solar evaporator based on the sandwich-like nanoplates showed a high solar-vapor conversion efficiency of 85.2%under a high light intensity of 10 kW.After 30 times recycle of seawater desalination,the conversion efficiency scarcely decreased.These sandwich-like nanoplates with enhanced thermal and chemical stability of Au NPs are promising in the practical application of seawater desalination.展开更多
文摘Aim To prepare the prolonged-released microspheres of mefformin hydrochloride. Methods Ion-exchange resin-drug mefformin hydrochloride complexes were prepared as core materials, and followed by coating using ethylcellulose （EC） by the emulsion solvent diffusion technique. The release rate of mefformin from the microcapsules was highly dependent on the encapsulating formulation, thus being used as an index for formulation screening. Orthogonal experiments were performed to optimize the coating formulation. Results The final chosen formulation for coating of mefformin microcapsules were as follows： （ 1 ） the ratio of EC （20cps） to EC （45cps） was 50：50; （2） the ratio of plasticizer to coating materials was 20% ;and （3） the ratio of resin-mefformin complexes to coating materials was 5 ： 1. Conclusion The prolonged release microspheres of mefformin hydrochloride were successfully prepared.
基金The National Basic Research Program of China(973Program)(No.2009CB623203)the National Natural Science Foundation of China(No.51078186)+2 种基金Program for Special Talents in Six Fields of Jiangsu Province(No.2008169)the Natural Science Foundation of Jiangsu Province(No.BK2010071)China Postdoctoral Science Foundation(No.200902500)
文摘This paper applies the Debye-Hückel-Onsager electrolyte solution theory to investigate the diffusivity of ions in concrete pore solutions.First,a model of the diffusion coefficient associated with the ionic species,solution concentration and ambient temperature is proposed in the saturated concrete.Secondly,as an example,the effects of sodium chloride solution concentration,which are associated with influencing factors such as the ionic cloud radius,electrophoresis and relaxation,on the chloride diffusion coefficient are analyzed.It is found that the diffusion coefficient decreases with the increase in solution concentration,and the electrophoresis and ionic cloud radius are two important factors influencing the ionic diffusivity.Finally,the experiments,in which the chloride diffusion coefficients in specimens under different water-cement ratios are measured by the rapid chloride migration（RCM）method,are carried out to validate the effectiveness of the proposed model,and the results indicate that there is a generally reasonable agreement between the experimental and the proposed model results.
基金This work was supported by the National Natural Science Foundation of China(51732011,21431006,21761132008,81788101 and 11227901)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(21521001)+2 种基金the Key Research Program of Frontier Sciences,CAS(QYZDJ-SSW-SLH036)the National Basic Research Program of China(2014CB931800)the Users with Excellence and Scientific Research Grant of Hefei Science Center of CAS(2015HSC-UE007).This work was partially carried out at the USTC Center for Micro and Nanoscale Research and Fabrication.
文摘Solar evaporation based on plasmonic metal nanoparticles(MNPs)is emerging as a promising technology.However,the fine structure of MNPs is unstable,and both the high temperature generated by intensive light and corrosive ions in water could damage them.The performance will decline after recycling and long-time usage.To address these issues,we adopted a sponge-templating method for preparing sandwich-like nanoplates with the gold nanoparticles(Au NPs)confined in reduced graphene oxide(rGO)nanosheets.Due to the confinement effect,both the surface melting and ion diffusion were suppressed.The solar evaporator based on the sandwich-like nanoplates showed a high solar-vapor conversion efficiency of 85.2%under a high light intensity of 10 kW.After 30 times recycle of seawater desalination,the conversion efficiency scarcely decreased.These sandwich-like nanoplates with enhanced thermal and chemical stability of Au NPs are promising in the practical application of seawater desalination.
