The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dim...The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dimensional/two-dimensional(2D/2D)S-scheme heterojunction containing TpPa-1-COF/g-C_(3)N_(4) nanosheets(denoted as TPCNNS)was developed.The established maximum interfacial interaction between TpPa-1-COF NS and g-C_(3)N_(4) NS may result in aπ–πconjugated heterointerface.Furthermore,the difference in the work functions of TpPa-1-COF and g-C_(3)N_(4) results in a large Fermi level gap,leading to upward/downward band edge bending.The spontaneous interfacial charge transfer from g-C_(3)N_(4) to TpPa-1-COF at theπ–πconjugated interface area results in the presence of a built-in electric field,according to the charge density difference analysis based on density functional theory calculations.Such an enhanced built-in electric field can efficiently drive directional charge migration via the S-scheme mechanism,which enhances charge separation and utilization.Thus,an approximately 2.8 and 5.6 times increase in the photocatalytic hydrogen evolution rate was recorded in TPCNNS-2(1153μmol g^(-1) h^(-1))compared to pristine TpPa-1-COF and g-C_(3)N_(4) NS,respectively,under visible light irradiation.Overall,this work opens new avenues in the fabrication of 2D/2Dπ–πconjugated S-scheme heterojunction photocatalysts with highly efficient hydrogen evolution performance.展开更多
Two 3D 4-fold interpenetrated metal-organic frameworks, [Mn（L）（bpy）]n （1） and [Cu（HL）（bpy）]n （2）（H3L = 4,4＇,4＇＇-（benzene-1,3,5-triyl-tri（methyleneoxy）） tribenzoic acid, bpy = 4,4′-bipyridine）, we...Two 3D 4-fold interpenetrated metal-organic frameworks, [Mn（L）（bpy）]n （1） and [Cu（HL）（bpy）]n （2）（H3L = 4,4＇,4＇＇-（benzene-1,3,5-triyl-tri（methyleneoxy）） tribenzoic acid, bpy = 4,4′-bipyridine）, were synthesized under hydrothermal conditions, and characterized by element analyses, IR spectra, thermogravimetric analyses, X-ray powder diffraction and magnetic property studies. The single-crystal X-ray analyses revealed that 1 and 2 are homogeneous. 1 crystallizes in monoclinic, space group Cc with a = 26.794（2）, b = 11.6346（10）, c = 21.4614（18） ？, β = 91.570（2）°, V = 6687.9（10） A^3, Z = 8, Mr = 736.59, D = 1.463 g·cm^（-3）, μ = 0.458 mm^-1c, R（int） = 0.0524, F（000） = 3040, the final R = 0.0844 and wR = 0.2266 for 8092 observed reflections（I 〉 2σ（I））. 2 crystallizes in monoclinic, space group Cc with a = 27.609（12）, b = 11.126（10）, c = 21.490（9） ？, β = 92.131（2）°, V = 6597（5） A^3, Z = 8, Mr = 746.21, Dc = 1503 g·cm^（-3）, μ = 0.726 mm^-1, R（int） = 0.0542, F（000） = 3080, the final R =0.0681 and wR = 0.1831 for 6777 observed reflections（I 〉 2σ（I））. Two compounds are 3D [2＋2]-type 4-fold interpenetrated frameworks with（6^3）（6^9.8） hms topology. The magnetic study of compound 2 shows the presence of weak antiferromagnetic interaction between the Cu^Ⅱ ions in 2.展开更多
γ-(2,3-Epoxypropoxy)trimethoxysilane is a crucial silicone product synthesized by hydrosilylation.Its derived downstream silicone products have galvanized the development of silicone industry.However,the Speier's...γ-(2,3-Epoxypropoxy)trimethoxysilane is a crucial silicone product synthesized by hydrosilylation.Its derived downstream silicone products have galvanized the development of silicone industry.However,the Speier's or Karstedt's catalysts commonly utilized in its industrial process are homogeneous,leading to complications,such as low catalytic selectivity and recycling difficulty.Herein,a new heterogeneous platinum catalyst was developed by using a titanium-based metal organic framework(MIL-125)composite with polylactic acid(PAA)as the support.The as-synthesized Pt/PAA-2@MIL-125 catalyst exhibited impressive catalytic performance,producing a 97%yield inβ-product,and maintained recyclability for the synthesis ofγ-(2,3-epoxypropoxy)trimethoxysilane.Further characterization analyses revealed that the introduction of PAA resulted in the formation of a defective mesoporous MIL-125,which accelerated the transmission efficiency of reactants.Moreover,the abundant carboxylic acid groups in the MIL-125/PAA composite could interact strongly with Pt active species,thereby enhancing the catalytic performance and minimizing the loss of Pt,ultimately improving its cycling performance.The comprehensive experiments demonstrated the potential of this catalyst as an effective and versatile heterogeneous catalyst not only for the hydrosilylation of various olefins,but also for the hydrosilyation of silanes.展开更多
根据国家精品课程网站建设的要求,利用Visual Studio 2010开发平台和三层架构技术,结合C#语言、SQL Server2008数据库设计并实现了基于B/S的三层架构精品课程网站。详细介绍网站中的俱乐部模块及其在三层中的具体实现。该网站的建立,为...根据国家精品课程网站建设的要求,利用Visual Studio 2010开发平台和三层架构技术,结合C#语言、SQL Server2008数据库设计并实现了基于B/S的三层架构精品课程网站。详细介绍网站中的俱乐部模块及其在三层中的具体实现。该网站的建立,为实际网站开发提供了理论指导和方法依据。展开更多
目的本文通过对华东医院PACS系统和RIS系统集成运用中工作流程和数据流程的分析,提出了五种符合IHE工作流程环节的集成方法,并对其优缺点进行了讨论。方法华东医院PACS建设遵从医学影像通讯标准(Digital Imaging commu-nication in Medi...目的本文通过对华东医院PACS系统和RIS系统集成运用中工作流程和数据流程的分析,提出了五种符合IHE工作流程环节的集成方法,并对其优缺点进行了讨论。方法华东医院PACS建设遵从医学影像通讯标准(Digital Imaging commu-nication in Medicine,DICOM),系统主要由图像采集网关、中心服务器、图像显示工作站(包括诊断工作站和浏览工作站)和图像备份工作站组成。RIS系统以WEB技术为基础,主要由RIS服务器、RIS登记工作站、RIS检查工作站和RIS报告工作站组成。两系统间的信息交换可采用五种不同的方法进行。结果根据医院的实际情况,我们分别在PACS图像采集网关、中心服务器、RIS服务器和PACS诊断工作站上应用了这五种集成方法,并取得令人满意的效果。结论在医院的具体应用中,参照IHE所提出的工作流和数据流要求,我们所提出的这五种集成方法有其灵活、快速、易用、适用面广的优点,也存在HL7接口实现不足的弱点。展开更多
文摘The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dimensional/two-dimensional(2D/2D)S-scheme heterojunction containing TpPa-1-COF/g-C_(3)N_(4) nanosheets(denoted as TPCNNS)was developed.The established maximum interfacial interaction between TpPa-1-COF NS and g-C_(3)N_(4) NS may result in aπ–πconjugated heterointerface.Furthermore,the difference in the work functions of TpPa-1-COF and g-C_(3)N_(4) results in a large Fermi level gap,leading to upward/downward band edge bending.The spontaneous interfacial charge transfer from g-C_(3)N_(4) to TpPa-1-COF at theπ–πconjugated interface area results in the presence of a built-in electric field,according to the charge density difference analysis based on density functional theory calculations.Such an enhanced built-in electric field can efficiently drive directional charge migration via the S-scheme mechanism,which enhances charge separation and utilization.Thus,an approximately 2.8 and 5.6 times increase in the photocatalytic hydrogen evolution rate was recorded in TPCNNS-2(1153μmol g^(-1) h^(-1))compared to pristine TpPa-1-COF and g-C_(3)N_(4) NS,respectively,under visible light irradiation.Overall,this work opens new avenues in the fabrication of 2D/2Dπ–πconjugated S-scheme heterojunction photocatalysts with highly efficient hydrogen evolution performance.
基金Supported by the Education Committee of Sichuan Province(12ZA090,13CZ0019 and 14ZB0220)Key Laboratory of Green Catalysis of Sichuan Institutes of High Education(LZJ14201)Sichuan University of Science and Engineering(Y2014018)
文摘Two 3D 4-fold interpenetrated metal-organic frameworks, [Mn（L）（bpy）]n （1） and [Cu（HL）（bpy）]n （2）（H3L = 4,4＇,4＇＇-（benzene-1,3,5-triyl-tri（methyleneoxy）） tribenzoic acid, bpy = 4,4′-bipyridine）, were synthesized under hydrothermal conditions, and characterized by element analyses, IR spectra, thermogravimetric analyses, X-ray powder diffraction and magnetic property studies. The single-crystal X-ray analyses revealed that 1 and 2 are homogeneous. 1 crystallizes in monoclinic, space group Cc with a = 26.794（2）, b = 11.6346（10）, c = 21.4614（18） ？, β = 91.570（2）°, V = 6687.9（10） A^3, Z = 8, Mr = 736.59, D = 1.463 g·cm^（-3）, μ = 0.458 mm^-1c, R（int） = 0.0524, F（000） = 3040, the final R = 0.0844 and wR = 0.2266 for 8092 observed reflections（I 〉 2σ（I））. 2 crystallizes in monoclinic, space group Cc with a = 27.609（12）, b = 11.126（10）, c = 21.490（9） ？, β = 92.131（2）°, V = 6597（5） A^3, Z = 8, Mr = 746.21, Dc = 1503 g·cm^（-3）, μ = 0.726 mm^-1, R（int） = 0.0542, F（000） = 3080, the final R =0.0681 and wR = 0.1831 for 6777 observed reflections（I 〉 2σ（I））. Two compounds are 3D [2＋2]-type 4-fold interpenetrated frameworks with（6^3）（6^9.8） hms topology. The magnetic study of compound 2 shows the presence of weak antiferromagnetic interaction between the Cu^Ⅱ ions in 2.
基金supported by the National Natural Science Foundation of China(Nos.22262023,22261032,21961021)the Natural Science Foundation of Jiangxi Province,China(No.20202ACB203001)the Fund of Key Laboratory of Nanchang City,China(No.2021NCZDSY-005).
文摘γ-(2,3-Epoxypropoxy)trimethoxysilane is a crucial silicone product synthesized by hydrosilylation.Its derived downstream silicone products have galvanized the development of silicone industry.However,the Speier's or Karstedt's catalysts commonly utilized in its industrial process are homogeneous,leading to complications,such as low catalytic selectivity and recycling difficulty.Herein,a new heterogeneous platinum catalyst was developed by using a titanium-based metal organic framework(MIL-125)composite with polylactic acid(PAA)as the support.The as-synthesized Pt/PAA-2@MIL-125 catalyst exhibited impressive catalytic performance,producing a 97%yield inβ-product,and maintained recyclability for the synthesis ofγ-(2,3-epoxypropoxy)trimethoxysilane.Further characterization analyses revealed that the introduction of PAA resulted in the formation of a defective mesoporous MIL-125,which accelerated the transmission efficiency of reactants.Moreover,the abundant carboxylic acid groups in the MIL-125/PAA composite could interact strongly with Pt active species,thereby enhancing the catalytic performance and minimizing the loss of Pt,ultimately improving its cycling performance.The comprehensive experiments demonstrated the potential of this catalyst as an effective and versatile heterogeneous catalyst not only for the hydrosilylation of various olefins,but also for the hydrosilyation of silanes.
文摘目的本文通过对华东医院PACS系统和RIS系统集成运用中工作流程和数据流程的分析,提出了五种符合IHE工作流程环节的集成方法,并对其优缺点进行了讨论。方法华东医院PACS建设遵从医学影像通讯标准(Digital Imaging commu-nication in Medicine,DICOM),系统主要由图像采集网关、中心服务器、图像显示工作站(包括诊断工作站和浏览工作站)和图像备份工作站组成。RIS系统以WEB技术为基础,主要由RIS服务器、RIS登记工作站、RIS检查工作站和RIS报告工作站组成。两系统间的信息交换可采用五种不同的方法进行。结果根据医院的实际情况,我们分别在PACS图像采集网关、中心服务器、RIS服务器和PACS诊断工作站上应用了这五种集成方法,并取得令人满意的效果。结论在医院的具体应用中,参照IHE所提出的工作流和数据流要求,我们所提出的这五种集成方法有其灵活、快速、易用、适用面广的优点,也存在HL7接口实现不足的弱点。
