A WC-supported S_2O 2-_8/ZrO_2(PSZ) catalyst was prepared and characterized by means of XRD, BET, FTIR and XPS. The isomerization of n-pentane over the catalyst was investigated as well. The results show that the s...A WC-supported S_2O 2-_8/ZrO_2(PSZ) catalyst was prepared and characterized by means of XRD, BET, FTIR and XPS. The isomerization of n-pentane over the catalyst was investigated as well. The results show that the skeletal isomerization and the crack of n-pentane proceed simultaneously on WC-supported S_2O 2-_8/ZrO_2 catalyst. The addition of tungsten carbide showed a significant enhancement in the activity and stability of the catalyst for n-pentane isomerization. The catalyst showed evidently a better activity than S_2O 2-_8/ZrO_2 supported by Pt and WO_3. The results can be interpreted by the existence of the tungsten oxycarbide compound(WC_xO_y) with carbidic, oxide and acidic sites.展开更多
This paper proposes that it is necessary to implement the concept of tourist carrying capacity to facilitate the tourism planning, and presents a method to evaluate the carrying capacity. The method called matter elem...This paper proposes that it is necessary to implement the concept of tourist carrying capacity to facilitate the tourism planning, and presents a method to evaluate the carrying capacity. The method called matter element analysis can solve the uncertain and incompatible problem of the evaluated factors in assessing carrying capacity.The current state of a destination's carrying capacity can be determined by establishing the standard indexes and the matter element model. Through the evaluating of the travel industry zones of the Autonomous Prefecture of Western Hunan, the method is proved to be simple and feasible, and it is improved to be significant for the tourism planning and determination as well as the sustainable development of the regional tourism.展开更多
文摘A WC-supported S_2O 2-_8/ZrO_2(PSZ) catalyst was prepared and characterized by means of XRD, BET, FTIR and XPS. The isomerization of n-pentane over the catalyst was investigated as well. The results show that the skeletal isomerization and the crack of n-pentane proceed simultaneously on WC-supported S_2O 2-_8/ZrO_2 catalyst. The addition of tungsten carbide showed a significant enhancement in the activity and stability of the catalyst for n-pentane isomerization. The catalyst showed evidently a better activity than S_2O 2-_8/ZrO_2 supported by Pt and WO_3. The results can be interpreted by the existence of the tungsten oxycarbide compound(WC_xO_y) with carbidic, oxide and acidic sites.
基金Supported by the Natural Science Foundation of China for Distinguished Young Scholars(No.50425927),the Key Project of National Development and Reform Commission of China(No.2002BA516A15-12),and the Natural Science Foundations of Hunan(No.04JJ3013).
文摘This paper proposes that it is necessary to implement the concept of tourist carrying capacity to facilitate the tourism planning, and presents a method to evaluate the carrying capacity. The method called matter element analysis can solve the uncertain and incompatible problem of the evaluated factors in assessing carrying capacity.The current state of a destination's carrying capacity can be determined by establishing the standard indexes and the matter element model. Through the evaluating of the travel industry zones of the Autonomous Prefecture of Western Hunan, the method is proved to be simple and feasible, and it is improved to be significant for the tourism planning and determination as well as the sustainable development of the regional tourism.
