An immature pinecone shaped hierarchically structured zirconia （ZrO2-ipch） and a cobblestone-like zirconia nanoparticulate （ZrO2-cs）, both with the monoclinic phase （m-phase）, were synthesized by the facile hydr...An immature pinecone shaped hierarchically structured zirconia （ZrO2-ipch） and a cobblestone-like zirconia nanoparticulate （ZrO2-cs）, both with the monoclinic phase （m-phase）, were synthesized by the facile hydrothermal method and used as the support for a Ni catalyst for the dry reforming of methane （DRM） with CO2. ZrO2-ipch is a much better support than ZrO2-cs and the traditional ZrO2 irregular particles made by a simple precipitation method （ZrO2-ip）. The supported Ni catalyst on ZrO2-ipch （Ni/ZrO2-ipch） exhibited outstanding catalytic activity and coke-resistant stability compared to the ones on ZrO2-cs （Ni/ZrO2-cs） and ZrO2-ip （Ni/ZrO2-ip）. Ni/ZrO2-ip exhibited the worst catalytic performance. The origin of the significantly enhanced catalytic performance was revealed by characterization including XRD, N2 adsorption measurement （BET）, TEM, H2-TPR, CO chemisorption, CO2-TPD, XPS and TGA. The superior catalytic activity of Ni/ZrO2-ipch to Ni/ZrO2-cs or Ni/ZrO2-ip was ascribed to a higher Ni dispersion, increased reducibility, enhanced oxygen mo- bility, and more basic sites with a higher strength, which were due to the unique hierarchically structural morphology of the ZrO2-ipch support. Ni/ZrO2-ipch exhibited better stability for the DRM reaction than Ni/ZrO2-ip, which was ascribed to its higher resistance to Ni sintering due to a strengthened metal-support interaction and the confinement effect of the mesopores and coke deposition resistance. The higher coking resistance of Ni/ZrO2-ipch for the DRM reaction in comparison with Ni/ZrOz-ip orignated from the coke-removalabitity of the higher amount of lattice oxygen and more basic sites, confirmed by XPS and CO2-TPD analysis, and the stabilized Ni on the Ni/ZrO2-ipch catalyst by the confinement effect of the mesopores of the hierarchical ZrO2-ipch sup- port. The superior catalytic performance and coking resistance of the Ni/ZrO2-ipch catalyst makes it a promising candidate for synthesis gas production from the DRM reaction.展开更多
Since 2015, a “reform storm” of Environmental Impact Assessment (EIA) opened up in China. This study tries to answer the question of whether these reforms improve the effectiveness of EIA. First, we elaborate on the...Since 2015, a “reform storm” of Environmental Impact Assessment (EIA) opened up in China. This study tries to answer the question of whether these reforms improve the effectiveness of EIA. First, we elaborate on the reforms along with three well-acknowledged components, including EIA legislation, administration, and process. Then, evaluate the reformed EIA system against revised Ahmad and Wood’s criteria. The results demonstrate that the revised laws and regulations are more stringent than the old versions. The EIA process is simplified, and its coordination with the pollutant discharge permit system is promoted. The interim and post-event supervision is currently more robust and the penalties are more severe than before. However, the hierarchical position of the Environmental Protection Law is not high enough and the coordination of different government departments is still challenging. In summary, despite the problems occurring at the initial phase of reforms, the effectiveness of the EIA system has largely been improved.展开更多
Objective: To investigate the model, quality as well as effect of teaching-in-English in five-year clinical medicine program of Hainan Medical University.Methods: The questionnaire was carried out among clinical medic...Objective: To investigate the model, quality as well as effect of teaching-in-English in five-year clinical medicine program of Hainan Medical University.Methods: The questionnaire was carried out among clinical medicine undergraduates of2012–2015 grades in Hainan Medical University, to investigate studying time, studying habits and the impact of teaching in English. Additionally results of CET-4, CET-6 and overseas internship from undergraduates of 2012–2015 grade, as well as the result of phased medical licensing examination and post-graduate entrance examination from undergraduates of 2012 were accordingly collected from the Teaching Management Department.Results: For the Chinese students in international classes, the average time of self-study was 161.49 min, 58.3% had preview before classes, and 90.7% had habit of review after classes. Thus the first time pass rate, total pass rate, first time excellent rate and total excellent rate of CET-4 and CET-6 of international classes were significantly higher than those of regular classes. The result of post-graduate entrance examination in 2016 showed that the score, pass rate and acceptance rate of international classes of 2012 grade were significantly higher those of regular classes(P < 0.01).Conclusions: Teaching-in-English reform in Hainan Medical University has achieved initial success. Chinese students from international classes are superior to those from regular classes in many aspects. However, there are still many problems, and effective measures should be implemented to promote teaching quality continuously.展开更多
In the purification process of automobile exhaust,existing water plays an important role as an oxidant,which converts CO and hydrocarbons（HCs） by the water-gas shift（WGS） and the steam reforming（SR） reactions,re...In the purification process of automobile exhaust,existing water plays an important role as an oxidant,which converts CO and hydrocarbons（HCs） by the water-gas shift（WGS） and the steam reforming（SR） reactions,respectively,especially at high temperatures.Meanwhile it is major component of the exhaust which can affect significantly the thermal stability of the three-way catalyst.Activity experiments were carried out close to the real operation conditions（GHSV,concentration,etc.） with a Pd/Ce0.67Zr0.33O2 catalyst supplying information on the CO and C3H8 oxidation reactions in feedstream formed by different reactant combinations.The obtained results showed that the activity of the CO and C3H8 oxidation was promoted by the addition of steam due to the WGS and SR reactions.The WGS and SR reaction were competitive under oxygen-lean conditions.The kinetic analysis was considered for WGS and SR reactions.展开更多
At present,there are a series of relatively difficult problems in the ideological and political course of colleges and universities.In the face of complicated situation,we still need keeping original intention and mis...At present,there are a series of relatively difficult problems in the ideological and political course of colleges and universities.In the face of complicated situation,we still need keeping original intention and mission,calmly dealing with the challenges from all sides,and exploring the opportunities contained therein.Meanwhile,we should grasp the overall situation in a macro sense,and use top level design to layout and plan change strategy.展开更多
Hydrogen production by steam reforming of ethylene glycol(EG) at 300℃ was investigated over SiO2 and CeO2 supported Pt–Ni bimetallic catalysts prepared by incipient wetness impregnation methods. It was observed that...Hydrogen production by steam reforming of ethylene glycol(EG) at 300℃ was investigated over SiO2 and CeO2 supported Pt–Ni bimetallic catalysts prepared by incipient wetness impregnation methods. It was observed that impregnation sequence of Pt and Ni can affect the performance of catalysts apparently. Catalyst with Pt first and then Ni addition showed higher EG conversion and H2 yield owing to the Ni enrichment on the surface and the proper interaction between Pt and Ni. It was observed that although SiO2 supported catalysts exhibited better activity and H2 selectivity, CeO2 supported ones had better stability. This is attributed to the less coke formation on CeO2. Increasing Pt/Ni ratio enhanced the reaction activity, and Pt3–Ni7 catalysts with 3 wt% Pt and 7 wt% Ni showed the highest activity and stability. Ni surficial enrichment facilitated the C-C bond rupture and water gas shift reactions;and Pt addition inhibited methanation reaction. Electron transfer and hydrogen spillover from Pt to Ni suppressed carbon deposition. These combined effects lead to the excellent performance of Pt3–Ni7 supported catalysts.展开更多
基金financially supported by the Joint Fund of Coal, set up by National Natural Science Foundation of China and Shenhua Co., Ltd.(U1261104)the National Natural Science Foundation of China (21276041)+3 种基金the Program for New Century Excellent Talents in University (NCET-12-0079)the Natural Science Foundation of Liaoning Province (2015020200)the Fundamental Research Funds for the Central Universities (DUT15LK41)the Science and Technology Development Program of Hangzhou (20130533B14)~~
文摘An immature pinecone shaped hierarchically structured zirconia （ZrO2-ipch） and a cobblestone-like zirconia nanoparticulate （ZrO2-cs）, both with the monoclinic phase （m-phase）, were synthesized by the facile hydrothermal method and used as the support for a Ni catalyst for the dry reforming of methane （DRM） with CO2. ZrO2-ipch is a much better support than ZrO2-cs and the traditional ZrO2 irregular particles made by a simple precipitation method （ZrO2-ip）. The supported Ni catalyst on ZrO2-ipch （Ni/ZrO2-ipch） exhibited outstanding catalytic activity and coke-resistant stability compared to the ones on ZrO2-cs （Ni/ZrO2-cs） and ZrO2-ip （Ni/ZrO2-ip）. Ni/ZrO2-ip exhibited the worst catalytic performance. The origin of the significantly enhanced catalytic performance was revealed by characterization including XRD, N2 adsorption measurement （BET）, TEM, H2-TPR, CO chemisorption, CO2-TPD, XPS and TGA. The superior catalytic activity of Ni/ZrO2-ipch to Ni/ZrO2-cs or Ni/ZrO2-ip was ascribed to a higher Ni dispersion, increased reducibility, enhanced oxygen mo- bility, and more basic sites with a higher strength, which were due to the unique hierarchically structural morphology of the ZrO2-ipch support. Ni/ZrO2-ipch exhibited better stability for the DRM reaction than Ni/ZrO2-ip, which was ascribed to its higher resistance to Ni sintering due to a strengthened metal-support interaction and the confinement effect of the mesopores and coke deposition resistance. The higher coking resistance of Ni/ZrO2-ipch for the DRM reaction in comparison with Ni/ZrOz-ip orignated from the coke-removalabitity of the higher amount of lattice oxygen and more basic sites, confirmed by XPS and CO2-TPD analysis, and the stabilized Ni on the Ni/ZrO2-ipch catalyst by the confinement effect of the mesopores of the hierarchical ZrO2-ipch sup- port. The superior catalytic performance and coking resistance of the Ni/ZrO2-ipch catalyst makes it a promising candidate for synthesis gas production from the DRM reaction.
文摘Since 2015, a “reform storm” of Environmental Impact Assessment (EIA) opened up in China. This study tries to answer the question of whether these reforms improve the effectiveness of EIA. First, we elaborate on the reforms along with three well-acknowledged components, including EIA legislation, administration, and process. Then, evaluate the reformed EIA system against revised Ahmad and Wood’s criteria. The results demonstrate that the revised laws and regulations are more stringent than the old versions. The EIA process is simplified, and its coordination with the pollutant discharge permit system is promoted. The interim and post-event supervision is currently more robust and the penalties are more severe than before. However, the hierarchical position of the Environmental Protection Law is not high enough and the coordination of different government departments is still challenging. In summary, despite the problems occurring at the initial phase of reforms, the effectiveness of the EIA system has largely been improved.
基金supported by Key Research and Development Project of Hainan Province(Grant No ZDXM2017123)
文摘Objective: To investigate the model, quality as well as effect of teaching-in-English in five-year clinical medicine program of Hainan Medical University.Methods: The questionnaire was carried out among clinical medicine undergraduates of2012–2015 grades in Hainan Medical University, to investigate studying time, studying habits and the impact of teaching in English. Additionally results of CET-4, CET-6 and overseas internship from undergraduates of 2012–2015 grade, as well as the result of phased medical licensing examination and post-graduate entrance examination from undergraduates of 2012 were accordingly collected from the Teaching Management Department.Results: For the Chinese students in international classes, the average time of self-study was 161.49 min, 58.3% had preview before classes, and 90.7% had habit of review after classes. Thus the first time pass rate, total pass rate, first time excellent rate and total excellent rate of CET-4 and CET-6 of international classes were significantly higher than those of regular classes. The result of post-graduate entrance examination in 2016 showed that the score, pass rate and acceptance rate of international classes of 2012 grade were significantly higher those of regular classes(P < 0.01).Conclusions: Teaching-in-English reform in Hainan Medical University has achieved initial success. Chinese students from international classes are superior to those from regular classes in many aspects. However, there are still many problems, and effective measures should be implemented to promote teaching quality continuously.
基金supported by the National High-Tech Research and Development Program of China(2009AA064803)
文摘In the purification process of automobile exhaust,existing water plays an important role as an oxidant,which converts CO and hydrocarbons（HCs） by the water-gas shift（WGS） and the steam reforming（SR） reactions,respectively,especially at high temperatures.Meanwhile it is major component of the exhaust which can affect significantly the thermal stability of the three-way catalyst.Activity experiments were carried out close to the real operation conditions（GHSV,concentration,etc.） with a Pd/Ce0.67Zr0.33O2 catalyst supplying information on the CO and C3H8 oxidation reactions in feedstream formed by different reactant combinations.The obtained results showed that the activity of the CO and C3H8 oxidation was promoted by the addition of steam due to the WGS and SR reactions.The WGS and SR reaction were competitive under oxygen-lean conditions.The kinetic analysis was considered for WGS and SR reactions.
文摘At present,there are a series of relatively difficult problems in the ideological and political course of colleges and universities.In the face of complicated situation,we still need keeping original intention and mission,calmly dealing with the challenges from all sides,and exploring the opportunities contained therein.Meanwhile,we should grasp the overall situation in a macro sense,and use top level design to layout and plan change strategy.
基金supported by Natural Science Foundation of China (Grant 21273193, 21473231 and 20973148)
文摘Hydrogen production by steam reforming of ethylene glycol(EG) at 300℃ was investigated over SiO2 and CeO2 supported Pt–Ni bimetallic catalysts prepared by incipient wetness impregnation methods. It was observed that impregnation sequence of Pt and Ni can affect the performance of catalysts apparently. Catalyst with Pt first and then Ni addition showed higher EG conversion and H2 yield owing to the Ni enrichment on the surface and the proper interaction between Pt and Ni. It was observed that although SiO2 supported catalysts exhibited better activity and H2 selectivity, CeO2 supported ones had better stability. This is attributed to the less coke formation on CeO2. Increasing Pt/Ni ratio enhanced the reaction activity, and Pt3–Ni7 catalysts with 3 wt% Pt and 7 wt% Ni showed the highest activity and stability. Ni surficial enrichment facilitated the C-C bond rupture and water gas shift reactions;and Pt addition inhibited methanation reaction. Electron transfer and hydrogen spillover from Pt to Ni suppressed carbon deposition. These combined effects lead to the excellent performance of Pt3–Ni7 supported catalysts.
