Nanometer SnO2 particles were synthesized by sol-gel dialytic processes and used as a support to prepare CuO supported catalysts via a deposition-precipitation method. The samples were characterized by means of TG-DTA...Nanometer SnO2 particles were synthesized by sol-gel dialytic processes and used as a support to prepare CuO supported catalysts via a deposition-precipitation method. The samples were characterized by means of TG-DTA, XRD, H2-TPR and XPS. The catalytic activity of the CuO/TiO2-SnO2 catalysts was markedly depended on the loading of CuO, and the optimum CuO loading was 8 wt.% （Tloo = 80 ℃）. The CuO/TiO2-SnO2 catalysts exhibited much higher catalytic activity than the CuO/TiO2 and CuO/SnO2 catalysts. H2-TPR result indicated that a large amount of CuO formed the active site for CO oxidation in 8 wt.% CuO/TiO2-SnO2 catalyst.展开更多
The development of maintenance hemodialysis(HD)for end stage kidney disease patients is a success story that continues to save many lives.Nevertheless,intermittent renal replacement therapy is also a source of recurre...The development of maintenance hemodialysis(HD)for end stage kidney disease patients is a success story that continues to save many lives.Nevertheless,intermittent renal replacement therapy is also a source of recurrent stress for patients.Conventional thrice weekly short HD is an imperfect treatment that only partially corrects uremic abnormalities,increases cardiovascular risk,and exacerbates disease burden.Altering cycles of fluid loading associated with cardiac stretching(interdialytic phase)and then fluid unloading(intradialytic phase)likely contribute to cardiac and vascular damage.This unphysiologic treatment profile combined with cyclic disturbances including osmotic and electrolytic shifts may contribute to morbidity in dialysis patients and augment the health burdenof treatment. As such, HD patients are exposed to multiple stressors including cardiocirculatory,inflammatory, biologic, hypoxemic, and nutritional. This cascade of events can be termed thedialysis stress storm and sickness syndrome. Mitigating cardiovascular risk and morbidityassociated with conventional intermittent HD appears to be a priority for improving patientexperience and reducing disease burden. In this in-depth review, we summarize the hidden effectsof intermittent HD therapy, and call for action to improve delivered HD and develop treatmentschedules that are better tolerated and associated with fewer adverse effects.展开更多
Nanosized tin dioxide particles were prepared by sol-gel dialytic processes with tin(Ⅳ) chloride and alcohol as start materials. The nanoparticles of tin dioxide were charactered by thermogravimetry and differential ...Nanosized tin dioxide particles were prepared by sol-gel dialytic processes with tin(Ⅳ) chloride and alcohol as start materials. The nanoparticles of tin dioxide were charactered by thermogravimetry and differential thermal analysis(TG-DTA), X-ray diffraction(XRD), transmission electron microscopy (TEM) and BET. The results show that the average diameter of tin dioxide particles dried at 353 K was about 2 nm. Even if the tin dioxide particles were calcined at 873 K, the average diameter of particles was less than 10 nm. The removal of Cl- was solved by using this kind of method. The mechanism of the formation of tin dioxide nanosized particles was proposed and analyzed in this paper. We also measured the sensitivity of the sensor based on the tin oxide powder calcined at 673 K to NH 3, alcohol, acetone, hexane and CO. The gas-sensing performance results indicate that this sensor has a higher sensitivity to alcohol and acetone, and selectivity for NH 3, hexane and CO at an operating temperature of 343 K.展开更多
基金supported by the National Natural Science Foundation of China (20771061 and 20871071)the 973 Program (2005CB623607)Science and Technology Commission Foundation of Tianjin (08JCYBJC00100 and 09JCYBJC03600)
文摘Nanometer SnO2 particles were synthesized by sol-gel dialytic processes and used as a support to prepare CuO supported catalysts via a deposition-precipitation method. The samples were characterized by means of TG-DTA, XRD, H2-TPR and XPS. The catalytic activity of the CuO/TiO2-SnO2 catalysts was markedly depended on the loading of CuO, and the optimum CuO loading was 8 wt.% （Tloo = 80 ℃）. The CuO/TiO2-SnO2 catalysts exhibited much higher catalytic activity than the CuO/TiO2 and CuO/SnO2 catalysts. H2-TPR result indicated that a large amount of CuO formed the active site for CO oxidation in 8 wt.% CuO/TiO2-SnO2 catalyst.
文摘The development of maintenance hemodialysis(HD)for end stage kidney disease patients is a success story that continues to save many lives.Nevertheless,intermittent renal replacement therapy is also a source of recurrent stress for patients.Conventional thrice weekly short HD is an imperfect treatment that only partially corrects uremic abnormalities,increases cardiovascular risk,and exacerbates disease burden.Altering cycles of fluid loading associated with cardiac stretching(interdialytic phase)and then fluid unloading(intradialytic phase)likely contribute to cardiac and vascular damage.This unphysiologic treatment profile combined with cyclic disturbances including osmotic and electrolytic shifts may contribute to morbidity in dialysis patients and augment the health burdenof treatment. As such, HD patients are exposed to multiple stressors including cardiocirculatory,inflammatory, biologic, hypoxemic, and nutritional. This cascade of events can be termed thedialysis stress storm and sickness syndrome. Mitigating cardiovascular risk and morbidityassociated with conventional intermittent HD appears to be a priority for improving patientexperience and reducing disease burden. In this in-depth review, we summarize the hidden effectsof intermittent HD therapy, and call for action to improve delivered HD and develop treatmentschedules that are better tolerated and associated with fewer adverse effects.
基金Supported by the National Natural Science Foundation of China(No.2 0 2 710 2 8) and Tianjin Natural Science Founda-tion(No.0 336 0 2 5 11)
文摘Nanosized tin dioxide particles were prepared by sol-gel dialytic processes with tin(Ⅳ) chloride and alcohol as start materials. The nanoparticles of tin dioxide were charactered by thermogravimetry and differential thermal analysis(TG-DTA), X-ray diffraction(XRD), transmission electron microscopy (TEM) and BET. The results show that the average diameter of tin dioxide particles dried at 353 K was about 2 nm. Even if the tin dioxide particles were calcined at 873 K, the average diameter of particles was less than 10 nm. The removal of Cl- was solved by using this kind of method. The mechanism of the formation of tin dioxide nanosized particles was proposed and analyzed in this paper. We also measured the sensitivity of the sensor based on the tin oxide powder calcined at 673 K to NH 3, alcohol, acetone, hexane and CO. The gas-sensing performance results indicate that this sensor has a higher sensitivity to alcohol and acetone, and selectivity for NH 3, hexane and CO at an operating temperature of 343 K.
