Zeolitic imidazolate framework-8(ZIF-8) was prepared through a solve-thermal reaction method and then shaped using different additives. The in fluence of the shaping conditions on the microstructure of the shaped samp...Zeolitic imidazolate framework-8(ZIF-8) was prepared through a solve-thermal reaction method and then shaped using different additives. The in fluence of the shaping conditions on the microstructure of the shaped samples was characterized by the XRD, BET, and SEM techniques. The results demonstrate that the compressive strength of the various shaped tablets is greatly increased and capable of meeting the industrial requirements compared to the unshaped ZIF-8 and that the loss rate of speci fic surface areas was maintained at 10% after the addition of 10%(by mass) binder and 10%(by mass) solvent. The adsorption isotherms of CO2, CH4, C3H8, and C3H6 on powdery ZIF-8and the shaped tablets(T-shaped ZIF-8, C-shaped ZIF-8, and N-shaped ZIF-8) were determined through volumetric measurements under different pressures and temperatures(298.2, 323.2, and 348.2 K). The adsorption capacities of the gases on both the ZIF-8 powder and the shaped tablets follow the order C3H6 N C3H8N CO2 N CH4. Furthermore,the results show that the adsorption capacities of the gases on the shaped tablets are lower by approximately 10%–20% than those on the powdery ZIF-8. In fact, the adsorption equilibrium isotherms for CO2, CH4, C3H8, and C3H6 on both powdery and shaped ZIF-8 can be well described by the Langmuir equation.展开更多
目的应用循证医学Meta分析来评价CT和MRI对股骨头缺血坏死（ avascular necrosis of the femoral head, ANFH）诊断的应用价值。方法检索cochrane图书馆（2011年第1期）、PubMed（1966～2011）、Embase（1989～2011）、中国生物医学文...目的应用循证医学Meta分析来评价CT和MRI对股骨头缺血坏死（ avascular necrosis of the femoral head, ANFH）诊断的应用价值。方法检索cochrane图书馆（2011年第1期）、PubMed（1966～2011）、Embase（1989～2011）、中国生物医学文献数据库（1982～2011）、万方数据库（1982—2011），纳入国内外公开发表的关于股骨头缺血坏死的CT和MRI诊断的文献，按照纳入标准进行筛选，两名调查员独立对文献质量进行严格评价和资料提取，对符合标准的8篇文献在诊断ANFH方面使用软件Review mangager5．0进行Meta分析。结果共纳入8篇研究，共515例患者。Meta分析及其偏倚分歧提示MRI对股骨头缺血坏死阳性率的诊断价值高于CT，两者差别有显著统计学意义[OR=0．12（95％CI，0．04～0．33），P〈0．0001]。MRI对股骨头缺血坏死早期阳性率的诊断价值高于CT，两者差别有统计学意义[OR=0．45（95％CI，0．26～0．78），P=0．005]。结论MRI是首选的股骨头缺血坏死诊断手段，但仍需大样本随机对照试验来验证。展开更多
基金Supported by the National Natural Science Foundation of China(21176010,21476009,21406007,and U1462104)
文摘Zeolitic imidazolate framework-8(ZIF-8) was prepared through a solve-thermal reaction method and then shaped using different additives. The in fluence of the shaping conditions on the microstructure of the shaped samples was characterized by the XRD, BET, and SEM techniques. The results demonstrate that the compressive strength of the various shaped tablets is greatly increased and capable of meeting the industrial requirements compared to the unshaped ZIF-8 and that the loss rate of speci fic surface areas was maintained at 10% after the addition of 10%(by mass) binder and 10%(by mass) solvent. The adsorption isotherms of CO2, CH4, C3H8, and C3H6 on powdery ZIF-8and the shaped tablets(T-shaped ZIF-8, C-shaped ZIF-8, and N-shaped ZIF-8) were determined through volumetric measurements under different pressures and temperatures(298.2, 323.2, and 348.2 K). The adsorption capacities of the gases on both the ZIF-8 powder and the shaped tablets follow the order C3H6 N C3H8N CO2 N CH4. Furthermore,the results show that the adsorption capacities of the gases on the shaped tablets are lower by approximately 10%–20% than those on the powdery ZIF-8. In fact, the adsorption equilibrium isotherms for CO2, CH4, C3H8, and C3H6 on both powdery and shaped ZIF-8 can be well described by the Langmuir equation.
文摘目的应用循证医学Meta分析来评价CT和MRI对股骨头缺血坏死（ avascular necrosis of the femoral head, ANFH）诊断的应用价值。方法检索cochrane图书馆（2011年第1期）、PubMed（1966～2011）、Embase（1989～2011）、中国生物医学文献数据库（1982～2011）、万方数据库（1982—2011），纳入国内外公开发表的关于股骨头缺血坏死的CT和MRI诊断的文献，按照纳入标准进行筛选，两名调查员独立对文献质量进行严格评价和资料提取，对符合标准的8篇文献在诊断ANFH方面使用软件Review mangager5．0进行Meta分析。结果共纳入8篇研究，共515例患者。Meta分析及其偏倚分歧提示MRI对股骨头缺血坏死阳性率的诊断价值高于CT，两者差别有显著统计学意义[OR=0．12（95％CI，0．04～0．33），P〈0．0001]。MRI对股骨头缺血坏死早期阳性率的诊断价值高于CT，两者差别有统计学意义[OR=0．45（95％CI，0．26～0．78），P=0．005]。结论MRI是首选的股骨头缺血坏死诊断手段，但仍需大样本随机对照试验来验证。
