Environmental cleaning is an important aspect of bacteria control.Ethyl cellulose microcapsules containing potassium monopersulfate(PMCM)were prepared by emulsified solvent diffusion method.The chemical structure and ...Environmental cleaning is an important aspect of bacteria control.Ethyl cellulose microcapsules containing potassium monopersulfate(PMCM)were prepared by emulsified solvent diffusion method.The chemical structure and microstructure of the obtained PMCM was characterized by methods of Fourier transform infrared spectroscopy(FT-IR),optical microscopy,scanning electron microscopy and X-ACT energy dispersive X-ray spectroscopy.The SEM micrographs of the PMCM containing 21.6%of C,46.8%of O,10.7%of S and 19.4%of K was relatively smooth.Thermal stability,sustained release performance,and antimicrobial activity of PMCM were investigated.The results showed that the drug loading and encapsulation efficiency of PMCM were 30.3%and 42.6%respectively.Potassium monopersulfate was fully released after 8 h,following a Fickian diffusion mechanism.Results showed that the microcapsules prepared with a high concentration of potassium monopersulfate solution showed a good antimicrobial effect.The microcapsule wall of the resulting PMCM increased with increasing ethyl cellulose content and had high thermal stability from the data of 69%residue rate.The excellent thermal stability and high sustained release performance of PMCM showed high application value.展开更多
K2Ti2O5 and LixK2-xTi2O5 samples with varying K contents (x=0.125, 0.15, 0.3), targeted on removal of two main environmental pollutants: PM and NOx, were synthesized by the solid state method using TiO2, KNO3 and LiOH...K2Ti2O5 and LixK2-xTi2O5 samples with varying K contents (x=0.125, 0.15, 0.3), targeted on removal of two main environmental pollutants: PM and NOx, were synthesized by the solid state method using TiO2, KNO3 and LiOH·H2O as starting materials and were characterized by X-ray diffractometry, scanning electron microscopy, and BET. The catalytic activity of titanate catalysts on PM oxidation was evaluated using the temperature programmed oxidation (TPO) method. The test results showed that the perovskite structure of K2Ti2O5 was still retained after doping a small amount of Li, and the catalytic performance of LixK2-xTi2O5 had been improved significantly compared with that of K2Ti2O5. Li0.15K1.85Ti2O5 catalyst had the highest catalytic activity with an ignition temperature of 210 ℃ and a peak temperature of 290 ℃. The catalytic activity of both K2Ti2O5 and LixK2-xTi2O5 under intimate contact was higher than that under loose contact. When the exhaust gas flow rate was around 100 mL/min, the catalyst samples showed a highest activity. The Li doped K2Ti2O5 could be an excellent candidate for PM oxidation due to its high oxidation activity, water stability, resistance to sulfur poisoning and economical advantages.展开更多
基金support From the Open Fund Project of Key Lab.of Biomass Energy and Material,Jiangsu Province(JSBEM201907)the Ordinary University Young Innovative Talents Project of Guangdong Province(2018KQNCX119).
文摘Environmental cleaning is an important aspect of bacteria control.Ethyl cellulose microcapsules containing potassium monopersulfate(PMCM)were prepared by emulsified solvent diffusion method.The chemical structure and microstructure of the obtained PMCM was characterized by methods of Fourier transform infrared spectroscopy(FT-IR),optical microscopy,scanning electron microscopy and X-ACT energy dispersive X-ray spectroscopy.The SEM micrographs of the PMCM containing 21.6%of C,46.8%of O,10.7%of S and 19.4%of K was relatively smooth.Thermal stability,sustained release performance,and antimicrobial activity of PMCM were investigated.The results showed that the drug loading and encapsulation efficiency of PMCM were 30.3%and 42.6%respectively.Potassium monopersulfate was fully released after 8 h,following a Fickian diffusion mechanism.Results showed that the microcapsules prepared with a high concentration of potassium monopersulfate solution showed a good antimicrobial effect.The microcapsule wall of the resulting PMCM increased with increasing ethyl cellulose content and had high thermal stability from the data of 69%residue rate.The excellent thermal stability and high sustained release performance of PMCM showed high application value.
基金supports provided for this research by the Education Department of Liaoning Province of China (No. 2009T061)Ministry of Education of China (No. [2010] 1561)
文摘K2Ti2O5 and LixK2-xTi2O5 samples with varying K contents (x=0.125, 0.15, 0.3), targeted on removal of two main environmental pollutants: PM and NOx, were synthesized by the solid state method using TiO2, KNO3 and LiOH·H2O as starting materials and were characterized by X-ray diffractometry, scanning electron microscopy, and BET. The catalytic activity of titanate catalysts on PM oxidation was evaluated using the temperature programmed oxidation (TPO) method. The test results showed that the perovskite structure of K2Ti2O5 was still retained after doping a small amount of Li, and the catalytic performance of LixK2-xTi2O5 had been improved significantly compared with that of K2Ti2O5. Li0.15K1.85Ti2O5 catalyst had the highest catalytic activity with an ignition temperature of 210 ℃ and a peak temperature of 290 ℃. The catalytic activity of both K2Ti2O5 and LixK2-xTi2O5 under intimate contact was higher than that under loose contact. When the exhaust gas flow rate was around 100 mL/min, the catalyst samples showed a highest activity. The Li doped K2Ti2O5 could be an excellent candidate for PM oxidation due to its high oxidation activity, water stability, resistance to sulfur poisoning and economical advantages.
