In several countries, the residual RHA (rice husk ash) has been produced in rice processing industries or in thermoelectric plants that use rice husk to generate heat and/or electrical energy, usually without burnin...In several countries, the residual RHA (rice husk ash) has been produced in rice processing industries or in thermoelectric plants that use rice husk to generate heat and/or electrical energy, usually without burning process control. This causes a reduction in the amorphous silica content of residual RHA, which distinguishes them from the RHA produced according to controlled burning process, which is totally amorphous and considered a highly reactive pozzolan. In this paper, the hydration products and the porous structure of binders paste were studied by replacing, in weight of 5%, 10% and 20% of Portland cement OPC (ordinary Portland cement), by residual RHAs named A and B, which have high and low content of amorphous silica, respectively, using microstructure evaluation techniques as XRD (X-ray diffraction), TG (thermogravimetric) tests and MIP (mercury intrusion porosimetry). A reducing the size of the pores of the pastes was observed according to the increase of content replacement of RHA A and RHA B.展开更多
Microparticles have a demonstrated value for drug delivery systems. The attempts to develop this tech- nology focus on the generation of featured microparticles for improving the function of the systems. Here, we pres...Microparticles have a demonstrated value for drug delivery systems. The attempts to develop this tech- nology focus on the generation of featured microparticles for improving the function of the systems. Here, we present a new type of microparticles with gelatin methacrylate (GelMa) cores and poly(L-lactide-co-glycolide) (PLGA) shells for syn- ergistic and sustained drug delivery applications. The mi- croparticles were fabricated by using GelMa aqueous solu- tion and PLGA oil solution as the raw materials of the mi- croflnidic double emulsion templates, in which hydrophilic and hydrophobic actives, such as doxorubicin hydrochloride (DOX, hydrophilic) and camptothecine (CPT, hydrophobic), could be loaded respectively. As the inner cores were poly- merized in the microfluidics when the double emulsions were formed, the hydrophilic actives could be trapped in the cores with high efficiency, and the rupture or fusion of the cores could be avoided during the solidification of the micropar- ticle shells with other actives. The size and component of the microparticles can be easily and precisely adjusted by ma- nipulating the flow solutions during the microfluidic emulsi- fication. Because of the solid structure of the resultant mi- croparticles, the encapsulated actives were released from the delivery systems only with the degradation of the biopolymer layers, and thus the burst release of the actives was avoided. These features of the microparticles make them ideal for drug delivery applications.展开更多
文摘In several countries, the residual RHA (rice husk ash) has been produced in rice processing industries or in thermoelectric plants that use rice husk to generate heat and/or electrical energy, usually without burning process control. This causes a reduction in the amorphous silica content of residual RHA, which distinguishes them from the RHA produced according to controlled burning process, which is totally amorphous and considered a highly reactive pozzolan. In this paper, the hydration products and the porous structure of binders paste were studied by replacing, in weight of 5%, 10% and 20% of Portland cement OPC (ordinary Portland cement), by residual RHAs named A and B, which have high and low content of amorphous silica, respectively, using microstructure evaluation techniques as XRD (X-ray diffraction), TG (thermogravimetric) tests and MIP (mercury intrusion porosimetry). A reducing the size of the pores of the pastes was observed according to the increase of content replacement of RHA A and RHA B.
基金supported by the National Natural Science Foundation of China (21473029 and 51522302) the NSAF Foundation of China (U1530260)+4 种基金the National Science Foundation of Jiangsu (BK20140028) the Program for New Century Excellent Talents in Universitythe Scientific Research Foundation of Southeast UniversityFoundation of Jiangsu Cancer Hospital (ZN201609)Beijing Medical Award Foundation (YJHYXKYJJ-433)
文摘Microparticles have a demonstrated value for drug delivery systems. The attempts to develop this tech- nology focus on the generation of featured microparticles for improving the function of the systems. Here, we present a new type of microparticles with gelatin methacrylate (GelMa) cores and poly(L-lactide-co-glycolide) (PLGA) shells for syn- ergistic and sustained drug delivery applications. The mi- croparticles were fabricated by using GelMa aqueous solu- tion and PLGA oil solution as the raw materials of the mi- croflnidic double emulsion templates, in which hydrophilic and hydrophobic actives, such as doxorubicin hydrochloride (DOX, hydrophilic) and camptothecine (CPT, hydrophobic), could be loaded respectively. As the inner cores were poly- merized in the microfluidics when the double emulsions were formed, the hydrophilic actives could be trapped in the cores with high efficiency, and the rupture or fusion of the cores could be avoided during the solidification of the micropar- ticle shells with other actives. The size and component of the microparticles can be easily and precisely adjusted by ma- nipulating the flow solutions during the microfluidic emulsi- fication. Because of the solid structure of the resultant mi- croparticles, the encapsulated actives were released from the delivery systems only with the degradation of the biopolymer layers, and thus the burst release of the actives was avoided. These features of the microparticles make them ideal for drug delivery applications.