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CuPc/FeNC双组分催化剂协同催化硝酸盐转化为氨

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Chinese Journal of Catalysis 2024年第1期56卷 104-113页

作者：王毅王硕付云凡桑佳琪臧一鹏魏鹏飞李合肥汪国雄包信和中国科学院大连化学物理研究所能源材料化学协同创新中心大连洁净能源国家实验室催化基础国家重点实验室辽宁大连116023 中国科学院大学能源学院北京100049

氨(NH_(3.)作为重要的化学品和能源储存介质,需求量与日俱增.本文旨在通过电化学硝酸根还原反应(NO_(3.^(−)RR),将NO_(3.^(−)转化为NH3.不仅解决了NO_(3.^(−)引起的环境污染问题,又可以满足对NH_(3.的迫切需求.然而,NO_(3.^(−)RR涉及多... 详细信息

氨(NH_(3.)作为重要的化学品和能源储存介质,需求量与日俱增.本文旨在通过电化学硝酸根还原反应(NO_(3.^(−)RR),将NO_(3.^(−)转化为NH3.不仅解决了NO_(3.^(−)引起的环境污染问题,又可以满足对NH_(3.的迫切需求.然而,NO_(3.^(−)RR涉及多个电子和质子转移过程,其中,NO_(2)^(−)是NO_(3.^(−)活化转化和深度还原合成NH_(3.的重要中间体.酞菁铜(CuPc)能够高效地活化转化NO_(3.^(−)为NO_(2)^(−),但在低过电位时无法有效地将NO2−还原为NH3.难以获得较高的氨法拉第效率(FENH3.和分电流密度.而氮配位的铁单原子催化剂(FeNC)则有较好的NO_(2)^(−)吸附活化特性.因此,利用双组分催化剂之间的协同作用以实现高效NO_(3.^(−)RR的活性和选择性是本文的主要研究思路.本文设计了CuPc/FeNC串联催化剂,利用CuPc和FeNC对NO_(3.^(−)和NO_(2)^(−)的吸附活化能力的差异,实现了高效的协同催化转化.X射线衍射、高角环形暗场扫描透射电镜、X射线光电子能谱及X射线吸收谱结果表明,FeNC催化剂中Fe原子均匀分布于ZIF-8热解后的基底.通过将FeNC和CuPc负载于气体扩散电极,在流动电解池中完成NO_(3.^(−)***/FeNC催化剂在较低电势区间中能够实现接近100%的NH3.拉第效率,同时在−0.57 V ***时达到273.mA cm–2的NH3.电流密度,并且在整个电势范围内有效地抑制了NO_(2)^(–)聚集.与单组分催化剂CuPc和FeNC对比结果表明,在−0.53.V ***时,CuPc/FeNC催化剂表现出较高的FE(NH_(3.)/FE(NO_(2)^(−))比值,是CuPc催化剂的50倍;同时CuPc/FeNC催化剂上NH3.电流密度是FeNC催化剂的1.5倍.进一步研究了NO_(3.^(–)RR中的串联反应机制,其中FeNC催化剂表现出较高的NO_(2)^(–)RR活性,并且有效抑制了析氢反应.此外,CuPc/FeNC催化剂和FeNC催化剂在NO_(2)^(−)RR中表现出类似的NH3.电流密度,这表明在NO_(3.^(−)RR中,CuPc/FeNC催化剂性能的提高来源于FeNC位点能够进一步还原CuPc位点产生的NO_(2)^(–).理论计算结果表明,FeNC比CuPc表现出更强的NO_(2)^(–)吸附活化能力,说明NO_(2)^(−)在FeNC上更容易进行加氢还原.NO_(3.^(−)RR反应全路径分析结果表明,对于^(*)NO_(3.还原到*NO2过程,CuPc相对于FeNC位点具有明显降低的反应自由能,说明CuPc有利于NO_(2)^(−)的生成;而FeNC位点在后续的^(*)NO_(2)还原合成^(*)NH_(3.过程中具有更低的反应自由能,这与实验结果一致.一系列非原位和原位表征证明了CuPc催化剂在高电位下存在少量金属颗粒析出,与CuPc催化剂在高电位下NH_(3.分电流密度快速增加结果一致.综上,本工作中CuPc和FeNC催化剂之间的协同作用弥补了各自的不足,通过串联反应机制,在低过电位下有效增加了NH_(3.的法拉第效率和电流密度,实现了高效的协同催化转化,为设计和合成高效催化剂提供了新思路.

关键词：硝酸根电化学还原为氨协同催化转化串联催化双组分催化剂动态现场原位表征

A Study on the Inclusion of α-Cyclodextrin with Mono-and 1,4-Disubstituted Benzenes by Neural Networks

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Chinese chemical Letters 1997年第2期8卷 145-148页

作者： Qing Xiang GUO Shi Dong CHU Yong Min WANG Zhong Xiao PAN Mao Sen ZHANG and You Cheng LIU(Department of chemical Physics, University of Science and Technology of China, hefei 23.026) Department of chemical Physics University of Science Technology of China Hefei 230026 China

The association constant (Ka) values were calculated by the function-strengthen ing neural networks (FNN) for the inclusion complexation of α-CD with mono- and 1,4-disubstituted benzenes. The lnKa predicted by FNN fr... 详细信息

关键词： Mono A Study on the Inclusion of Cyclodextrin with Mono-and 1,4-Disubstituted Benzenes by Neural Networks

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基于锥形四芯光纤的高灵敏度折射率传感器

激光与光电子学进展 2024年第17期61卷 160-165页

作者：高雅甄胜来金姝左铖赵斯阳李鹤飞俞本立安徽大学光电信息获取与控制教育部重点实验室安徽大学信息材料与智能感知安徽省实验室

提出了一种基于锥形四芯光纤的折射率传感器。四芯光纤两端熔接了多模光纤，并在氢氧火焰下逐渐拉细。通过模拟传感部分的光场证明了锥形四芯光纤会产生更强的干涉效应。实验结果表明，该传感器的最大折射率灵敏度达到了298.3.7 nm/RIU... 详细信息

提出了一种基于锥形四芯光纤的折射率传感器。四芯光纤两端熔接了多模光纤，并在氢氧火焰下逐渐拉细。通过模拟传感部分的光场证明了锥形四芯光纤会产生更强的干涉效应。实验结果表明，该传感器的最大折射率灵敏度达到了298.3.7 nm/RIU，线性度为99.806%，同时其对温度变化不敏感，有效地避免了温度与折射率之间的交叉敏感。该传感器具有体积小、灵敏度高的特点，在生物和化学传感领域具有潜在的应用前景。

关键词：光纤传感器折射率锥形四芯光纤温度

Synthesis of Perfluorinated Oxetane and Surface Properties of Its Cationic UV Cured Coating as a Reactive Additive

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chemical Research in Chinese Universities 2012年第3期28卷 550-554页

作者： ZHAN Fu,ZHANG Yong and SHI Wen-fang * CAS Key laboratory of Soft Matter Chemistry,Department of Polymer Science and Engineering,University of Science and Technology of China,hefei 23.026,P.R.China Department of Polymer Science and Engineering University of Science and Technology of China CAS Key Laboratory of Soft Matter Chemistry Hefei 230026

Perfluorinated oxetane(F-OXE) was synthesized via the ring-opening reaction of epoxy-functionalized oxetane with 2-(perfluorooctyl)ethanol under base-catalysis,and characterized by FTIR and 1 H NMR *** synthesized F-OXE was mixed with a commercial cationic UV curable resin,UVR6110,as a reactive additive at different mass fractions,and UV-irradiation cured in the presence of triphenylsulphonium hexafluoroantimonate as a cationic *** surface property study of cured films indicated that both hydrophobicity and oleophobicity were effectively enhanced by the addition of a small amount of *** contact angles of water and 1-bromonaphthalene on the surface of the cured film with 1.0%(mass fraction) F-OXE loading increased from 72 o to 106o and from 0o to 76o,respectively,compared with those on the surface of the film without F-OXE *** surface tension of UVR6110-F-OXE cured film decreased greatly from 55.6 mN/m of referenced film to 22.9 mN/*** results from X-ray photoelectron spectroscopy analysis confirm the migration and aggregation effect of perfluoroalkyl group to the surface of cured *** 1%(mass fraction) addition of F-OXE,the relative content of fluorine greatly increased from 0.70%(mass fraction) in the interior of the cured film to 3..73.(mass fraction) at the surface of the cured film,whereas those of carbon and oxygen decreased from 73.29% to 40.96% and from 26.00% to 22.3.%,respectively.

关键词： Cationic UV curing Oxetane Perfluoroalkyl Water and oil repellence

Metal-organic framework MIL-53.Al): synthesis, catalytic performance for the Friedel-Crafts acylation, and reaction mechanism

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Science China Chemistry 2015年第10期58卷 1544-1552页

作者： Junlei Yan Sai Jiang Shengfu Ji Da Shi hefei Cheng State Key laboratory of chemical Resource Engineering Beijing University of chemical Technology

Metal-organic framework MIL-53.Al) was synthesized by a solvothermal method using aluminum nitrate as the aluminium source and 1,4-benzenedicarboxylic acid(H2BDC) as the organic ligand. The structure of samples was characterized by X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FT-IR). The catalytic activity and recyclability of MIL-53.Al) catalyst for the Friedel-Crafts acylation reaction of indole with benzoyl chloride were evaluated. The reaction conditions were optimized and a reaction mechanism was suggested. The results showed that the MIL-53.Al) catalyst exhibited good catalytic activity and recyclability for the Friedel-Crafts acylation reaction. When the molar ratio of indole and MIL-53.Al) catalyst was 1:0.06(n1:ncatalyst), the molar ratio of indole and benzoyl chloride was 1:3. and the solvent was dichloromethane, the conversion of indole could reach 97.1% and the selectivity of 3.acylindole could reach 81.1% at 25 °C after 8 h. The catalyst can be reused without significant degradation in catalytic activity. After the catalyst was reused five times, the conversion of indole was 87.6% and the selectivity of 3.acylindole was 79.5%.

关键词： MIL-53.Al) catalyst Friedel-Crafts acylation indole 3.acylindoles

Ag/TiO_2光催化膜降解高浓度对氯苯酚溶液的研究

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太阳能学报 2003年第1期24卷 64-67页

作者：崔鹏徐南平时钧合肥工业大学化工学院合肥230009 南京工业大学膜科学技术研究所江苏省化学工程与技术重点实验室南京210009

依据光催化还原原理 ,在活性碳负载的TiO2 纳米粒子膜表面上制备出载银光催化剂 ,采用该催化剂对初始COD≥ 6 0 0mg·L-1的高浓度 4 氯苯酚水溶液进行降解研究 ,分别考察了光催化剂的用量、反应液初始浓度和初始 pH值等对降解性能的影... 详细信息

依据光催化还原原理 ,在活性碳负载的TiO2 纳米粒子膜表面上制备出载银光催化剂 ,采用该催化剂对初始COD≥ 6 0 0mg·L-1的高浓度 4 氯苯酚水溶液进行降解研究 ,分别考察了光催化剂的用量、反应液初始浓度和初始 pH值等对降解性能的影响 ,并与DegussaP2 5微粉光催化剂等进行比较 ,得出负载型Ag/TiO2 光催化膜具有光催化活性高、固液易分离的特点。

关键词：光催化催化剂对氯苯酚降解

A Study on the Driving Force for Binding of Benzene Derivatives by α-and β-Cyclodextrin

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Chinese chemical Letters 1998年第5期9卷 463-464页

作者： Shuang Hui LUO Hui Ming JMNG You Cheng LIU(National laboratory of Applied organic Chemistry, Lanzhou University, Lanzhou 73.000)Qing Xiang GUO (Department of Chemistry, University of Science and Technology of China, hefei 23.026) Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China Univ Sci & Technol China Dept Chem Hefei 230026 Peoples R China

A three-dimensional diagram shows that the association constants (Ka) for the inclusionof a- and 6-CD with substitUted benzene are mainly correIated with the molar refraction (R.) andhydrophobic constant (%) of the substitUents of guest compounds. It reveals that the inclusion ofcyclodextrin with the substitUted benzene is dondnantly driYen by van der Waals forces andhydrophobic interactions.

关键词： benzene derivatives cyclodextrin driving force inclusion complexation

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扩散渗析法回收铝箔腐蚀废液中硝酸

膜科学与技术 2017年第3期37卷 85-88,96页

作者：张旭王晓林吕燕汪小尧陶振李传润合肥工业大学化学与化工学院合肥230009 合肥水泥研究设计院合肥230051 合肥科佳高分子材料科技有限公司合肥230601

采用扩散渗析法回收铝箔腐蚀废液中的硝酸,主要考察流量、废液中硝酸铝浓度和硝酸浓度等因素对回收酸浓度、酸回收率以及铝离子截留率的影响.结果表明:回收酸浓度和酸回收率随着流量的增大而减小,随着废液中硝酸铝浓度的增大而增大;废... 详细信息

采用扩散渗析法回收铝箔腐蚀废液中的硝酸,主要考察流量、废液中硝酸铝浓度和硝酸浓度等因素对回收酸浓度、酸回收率以及铝离子截留率的影响.结果表明:回收酸浓度和酸回收率随着流量的增大而减小,随着废液中硝酸铝浓度的增大而增大;废液中硝酸浓度对回收酸浓度、酸回收率以及铝离子截留率的影响不大.综合本文的实验结果,酸回收率最高为84.90%,此时,流量为0.24L/h(流量比为1∶1)、废液中硝酸浓度为1.3.mol/L、硝酸铝浓度为0.49mol/L.

关键词：铝箔扩散渗析废酸液离子交换膜

Topological chirality and achirality of the closed circular DNAs

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Chinese Science Bulletin 1997年第20期42卷 1705-1708页

作者： QIU Wenyuan and XIN Houwen1. Department of chemical Physics, University of Science and Technology of China, hefei 23.026, China 2. Department of Chemistry, Lanzhou University, Lanzhou 73.000, China Department of chemical Physics University of Science and Technology of China Hefei China Department of Chemistry Lanzhou University I anzhou China

THE study of the relations between the topological structure and its function is one of the focus-es in modern chemistry and life science. In this note we set up a topological model to de-scribe the ccDNAs on the basis of Seifert construction in knot theory. Our model for theccDNAs helps to determine whether a structure is topologically chiral or achiral. This is one ofthe fundamental biological problems.

关键词： DNA topology knot theory topologiesl chirality topological achirality.