The selective oxidation of alcohol using molecular oxygen as an oxidant and water as a green sol‐vent is of great interest in green chemistry. In this work, we present a systematic study of a Pt/ZnO catalyst for the ...The selective oxidation of alcohol using molecular oxygen as an oxidant and water as a green sol‐vent is of great interest in green chemistry. In this work, we present a systematic study of a Pt/ZnO catalyst for the selective oxidation of benzyl alcohol at room temperature under base‐free aqueous conditions. Experimental observations and density functional theory calculations suggest that ZnO as a support can facilitate the adsorption of benzyl alcohol, which subsequently reacts with the activated oxygen species on the Pt catalyst, producing benzaldehyde. The resulting solid achieves a high conversion（94.1 ± 5.1% in 10 h） of benzyl alcohol and nearly 100% selectivity to benzalde‐hyde with ambient air as the oxidant. In addition, by introducing a small amount of Bi（1.78 wt%） into Pt/ZnO, we can further enhance the activity by 350%.展开更多
Development of CDOS catalyst for bottoms cracking is based on DOSY zeolite,which is characterized by high metal tolerance.The results of DOSY tests have shown that the catalyst has better activity retention at high me...Development of CDOS catalyst for bottoms cracking is based on DOSY zeolite,which is characterized by high metal tolerance.The results of DOSY tests have shown that the catalyst has better activity retention at high metal content in the feed.The performance of catalyst tested in the bench scale was superior over that of the reference catalyst.The results of catalyst application have shown that the CDOS series catalysts have better bottoms cracking activity,high metal tolerance,excellent dry gas selectivity,and enhanced liquid yield.展开更多
This paper aims at investigating architectural and urban heritage from the sociocultural point of view, which stands on the human asset of traditional sites such as the hawari of old Cairo. It analyzes the social prac...This paper aims at investigating architectural and urban heritage from the sociocultural point of view, which stands on the human asset of traditional sites such as the hawari of old Cairo. It analyzes the social practice of everyday life in one of the oldest Cairene hawari, Haret al Darb al Asfar. The focus is on architectural and spatial organization of outdoor and indoor spaces that coordinate the spatial practices of local community. A daily monitoring of people＇s activities and interviews was conducted in an investigation of how local people perceive their built environment between the house＇s interior and the outdoor shared space. It emerges that people construct their own field of private spheres according to complex patterns of daily activities that are not in line with the classical segregation between private and public in Islamic cities. This paper reports that the harah is basically a construct of social spheres that are organized spatially by the flexible development of individual buildings over time and in response to changes in individuals＇ needs and capabilities. In order to achieve sustainability in old urban quarters, the paper concludes, the focus should be directed towards the local organization of activities and a comprehensive upgrading of deteriorating buildings to match the changing needs of current population.展开更多
Nanomagnetic CoPt truncated octahedral nanoparticles （TONPs） were successfully synthesised through a facile one-pot strategy. These single crystal CoPt TONPs with an average size of about 8 nm exhibit excellent elec...Nanomagnetic CoPt truncated octahedral nanoparticles （TONPs） were successfully synthesised through a facile one-pot strategy. These single crystal CoPt TONPs with an average size of about 8 nm exhibit excellent electrocatalytic performance of both activity and stability for methanol oxidation reaction （MOR）. The mass and specific activities of CoPt TONPs is 8 and 6 times higher than that of standard commercial Pt/C, respectively. After accelerated durability test （ADT）, the loss of electrochemical surface area （ECSA） for CoPt TONPs is only 18.5%, which is significantly less than that of commercial Pt/C （68.2%）, indicating that CoPt TONPs possess much better stability than commercial Pt/C in the prolonged operation. The Curie temperature of CoPt TONPs down to 8 nm is as high as 350 K with weak ferromagntism at room temperature （RT）, which is greatly valuable for recycling in the eletrocatalytic applications.展开更多
基金supported by the National Natural Science Foundation of China (21703050, 21271153, 21373181)China Postdoctoral Science Foun‐dation (512200‐X91701)Special Research Foundation of Young Teachers in Hangzhou Dianzi University (ZX150204307002/032)~~
文摘The selective oxidation of alcohol using molecular oxygen as an oxidant and water as a green sol‐vent is of great interest in green chemistry. In this work, we present a systematic study of a Pt/ZnO catalyst for the selective oxidation of benzyl alcohol at room temperature under base‐free aqueous conditions. Experimental observations and density functional theory calculations suggest that ZnO as a support can facilitate the adsorption of benzyl alcohol, which subsequently reacts with the activated oxygen species on the Pt catalyst, producing benzaldehyde. The resulting solid achieves a high conversion（94.1 ± 5.1% in 10 h） of benzyl alcohol and nearly 100% selectivity to benzalde‐hyde with ambient air as the oxidant. In addition, by introducing a small amount of Bi（1.78 wt%） into Pt/ZnO, we can further enhance the activity by 350%.
基金support provided by the Sinopec Corporation (Contact number: 105111)
文摘Development of CDOS catalyst for bottoms cracking is based on DOSY zeolite,which is characterized by high metal tolerance.The results of DOSY tests have shown that the catalyst has better activity retention at high metal content in the feed.The performance of catalyst tested in the bench scale was superior over that of the reference catalyst.The results of catalyst application have shown that the CDOS series catalysts have better bottoms cracking activity,high metal tolerance,excellent dry gas selectivity,and enhanced liquid yield.
文摘This paper aims at investigating architectural and urban heritage from the sociocultural point of view, which stands on the human asset of traditional sites such as the hawari of old Cairo. It analyzes the social practice of everyday life in one of the oldest Cairene hawari, Haret al Darb al Asfar. The focus is on architectural and spatial organization of outdoor and indoor spaces that coordinate the spatial practices of local community. A daily monitoring of people＇s activities and interviews was conducted in an investigation of how local people perceive their built environment between the house＇s interior and the outdoor shared space. It emerges that people construct their own field of private spheres according to complex patterns of daily activities that are not in line with the classical segregation between private and public in Islamic cities. This paper reports that the harah is basically a construct of social spheres that are organized spatially by the flexible development of individual buildings over time and in response to changes in individuals＇ needs and capabilities. In order to achieve sustainability in old urban quarters, the paper concludes, the focus should be directed towards the local organization of activities and a comprehensive upgrading of deteriorating buildings to match the changing needs of current population.
基金supported by the National Basic Research Program of China(2015CB921401)the National Instrument Program of China(2012YQ120048)+2 种基金the National Natural Science Foundation of China(51625101,51431009,51471183,51331002,51371015,11274371 and 11674023)the Instrument Development Program of Chinese Academy of Sciences(YZ201345)the Fundamental Research Funds for the Central Universities(FRF-BR-15-009B)
文摘Nanomagnetic CoPt truncated octahedral nanoparticles （TONPs） were successfully synthesised through a facile one-pot strategy. These single crystal CoPt TONPs with an average size of about 8 nm exhibit excellent electrocatalytic performance of both activity and stability for methanol oxidation reaction （MOR）. The mass and specific activities of CoPt TONPs is 8 and 6 times higher than that of standard commercial Pt/C, respectively. After accelerated durability test （ADT）, the loss of electrochemical surface area （ECSA） for CoPt TONPs is only 18.5%, which is significantly less than that of commercial Pt/C （68.2%）, indicating that CoPt TONPs possess much better stability than commercial Pt/C in the prolonged operation. The Curie temperature of CoPt TONPs down to 8 nm is as high as 350 K with weak ferromagntism at room temperature （RT）, which is greatly valuable for recycling in the eletrocatalytic applications.
