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二维NiFe-N_(x)-C催化剂的制备及电催化二氧化碳还原性能研究
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作者 李京 李阳 +4 位作者 范晓彬 张凤宝 张国亮 夏清 彭文朝 《化学工业与工程》 CAS CSCD 北大核心 2024年第2期12-23,共12页
为降低碳基催化剂Ni-N位点上CO_(2)的活化能垒,并解决Fe-N位点上的CO中毒问题,以NaCl为模板,采用限制溶剂生长和热解法合成了具有NiFe-Nx双活性位点的超薄二维碳基催化剂(ZNF-900)。结果显示:ZNF-900具有超高的电催化CO_(2)还原生成CO... 为降低碳基催化剂Ni-N位点上CO_(2)的活化能垒,并解决Fe-N位点上的CO中毒问题,以NaCl为模板,采用限制溶剂生长和热解法合成了具有NiFe-Nx双活性位点的超薄二维碳基催化剂(ZNF-900)。结果显示:ZNF-900具有超高的电催化CO_(2)还原生成CO的选择性(FECO>97%)和电流密度(j_(CO)=37.3 mA·cm^(-2))。通过XPS、Raman等表征和EIS、Tafel斜率等电化学分析方法,证明Ni和Fe之间存在协同促进作用,从而促进了催化剂表面CO_(2)分子的吸附和CO产物的脱附。 展开更多
关键词 二维碳基催化剂 协同催化 CO_(2)还原 电催化
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有机催化3-氨基氧化吲哚与偶氮二羧酸酯的不对称加成反应
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作者 张健 田芳 王立新 《合成化学》 CAS 2024年第2期116-123,共8页
手性3,3-双取代氧化吲哚结构单元广泛存在于具有生物活性的天然产物和具有药物活性的化合物中,尤其存在于具有光学活性的3-氨基氧化吲哚中。此外,手性3,3-双取代氧化吲哚结构单元作为有效抗疟药(NITD609)、高效焦虑和抑郁抑制剂(SSR1494... 手性3,3-双取代氧化吲哚结构单元广泛存在于具有生物活性的天然产物和具有药物活性的化合物中,尤其存在于具有光学活性的3-氨基氧化吲哚中。此外,手性3,3-双取代氧化吲哚结构单元作为有效抗疟药(NITD609)、高效焦虑和抑郁抑制剂(SSR149415)以及HIV蛋白酶抑制剂而备受关注。因此,发展合成手性3-氨基氧化吲哚的新方法具有重要意义。为了实现反应的敏感性产物N,N′-缩靛红衍生物的不对称合成,使用金鸡纳碱衍生的方酰胺作催化剂,3-氨基氧化吲哚席夫碱与偶氮二羧酸酯作模板底物,最终以70%~85%的产率和45%~88%的对映选择性获得相应产物。该反应的实验条件温和,原子经济性高。 展开更多
关键词 N N′-缩靛红 不对称催化 3-氨基氧化吲哚席夫碱 偶氮二羧酸酯 亲电加成
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碱促进的(3aS,4R,6aR)-双苄基生物素转化为(3aS,4S,6aR)-双苄基生物素的研究
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作者 金剑炜 于绪平 +7 位作者 俞春晓 梁玲玲 宋少奇 肖群艳 徐晓攀 储楠 滕南鑫 吴春雷 《浙江化工》 CAS 2024年第10期38-44,共7页
目的:将生物素关键中体(3aS,4S,6aR)-双苄基生物素合成过程中产生的杂质(3aS,4R,6aR)-双苄基生物素经化学反应转化为产物(3aS,4S,6aR)-双苄基生物素。方法:通过碱催化反应,(3aS,4R,6aR)-双苄基生物素能顺利地转化为(3aS,4S,6aR)-双苄基... 目的:将生物素关键中体(3aS,4S,6aR)-双苄基生物素合成过程中产生的杂质(3aS,4R,6aR)-双苄基生物素经化学反应转化为产物(3aS,4S,6aR)-双苄基生物素。方法:通过碱催化反应,(3aS,4R,6aR)-双苄基生物素能顺利地转化为(3aS,4S,6aR)-双苄基生物素。结果:以异丙醇为溶剂,甲醇钠为催化剂,(3aS,4R,6aR)-双苄基生物素在25℃下搅拌24 h,以32.5%的收率得到(3aS,4S,6aR)-双苄基生物素。结论:该工艺为生物素工业生产中产生的杂质(3aS,4R,6aR)-双苄基生物素的回收利用提供了一种可行的方法。 展开更多
关键词 (3aS 4R 6aR)-双苄基生物素 (3aS 4S 6aR)-双苄基生物素 碱催化 手性翻转 消旋化
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Enhanced Acid/Base Catalysis in High Temperature Liquid Water 被引量:1
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作者 Xiu Yang LU Qi JING Zhun LI Lei YUAN Fei GAO Xin LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期841-844,共4页
Two novel and environmentally benign solvent systems, organic acids-ennchea high temperature liquid water (HTLW) and NH3-enriched HTLW, were developed, which can enhance the reaction rate of acid/base-catalyzed orga... Two novel and environmentally benign solvent systems, organic acids-ennchea high temperature liquid water (HTLW) and NH3-enriched HTLW, were developed, which can enhance the reaction rate of acid/base-catalyzed organic reactions in HTLW. We investigated the decomposition of fructose in organic acids-enriched HTLW, hydrolysis of cinnamaldehyde and aldol condensation of phenylaldehyde with acetaldehyde in NH3-enriched HTLW. The experimental results demonstrated that organic acids-enriched or NH3-enriched HTLW can greatly accelerate acid/base-catalyzed organic reactions in HTLW. 展开更多
关键词 High temperature liquid water acid/base-catalysis organic reactions.
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Synthesis,Crystal Structure and Characterization of a Nickel Complex Based on Phenoxyimine Ligand and Catalysis of the Vinyl Polymerization of Norbornene 被引量:1
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作者 周贤波 简丽菊 +4 位作者 张丹丹 林美君 李慧萍 陈建新 张治纯 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第11期1889-1895,共7页
The title complex N,O-bis{2-[[(2-benzhydryl-4,6-dimethylphenyl)imino]-methyl]-phenol}-nickel(II)(C56H48N2NiO2) has been synthesized by the reaction of 2-[[(2-benzhydryl-4,6-dimethylphenyl)mino]-methyl]-phenol ... The title complex N,O-bis{2-[[(2-benzhydryl-4,6-dimethylphenyl)imino]-methyl]-phenol}-nickel(II)(C56H48N2NiO2) has been synthesized by the reaction of 2-[[(2-benzhydryl-4,6-dimethylphenyl)mino]-methyl]-phenol with Ni(CH3COO)2·4 H2O, and characterized by elemental analysis and IR spectrum. The spatial structure of the complex has been confirmed by single-crystal X-ray diffraction analysis. The compound belongs to the monoclinic system, space group C2/c with a = 39.035(8), b = 13.276(3), c = 17.679(4) A°, β = 98.06(3)°, V = 9071(3) A°^3, C56H48N2NiO2, Mr = 839.67, Z = 8, Dc = 1.230 Mg/m^3, μ = 0.472 mm^-1, F(000) = 3536, T = 293(2) K, the final R = 0.0675 and w R = 0.1345(I 〉 2s(I)). The compound showed excellent catalytic activity up to 1.268 × 10^7 g of PNB(mol of Ni)^-1h^-1 for the addition polymerization of norbornene by using methylaluminoxane(MAO) as a cocatalyst. 展开更多
关键词 nickel complex SCHIFF-base crystal structure catalysis norbornene polymerization
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DICP Symposium (I) on Catalysis: Future Directions of Catalysis Science and Technology October 16-18, 2003, Dalian, China
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《Journal of Natural Gas Chemistry》 CAS CSCD 2003年第3期210-211,共2页
Introduction and Invitation DICP Symposium is a special series of interna-tional conference named after the Dalian Instituteof Chemical Physics (DICP). The DICP Symposiumwas founded with the purpose to promote the int... Introduction and Invitation DICP Symposium is a special series of interna-tional conference named after the Dalian Instituteof Chemical Physics (DICP). The DICP Symposiumwas founded with the purpose to promote the interna-tional communication and collaboration between theDICP and the international scientific community, to 展开更多
关键词 of on catalysis China DICP Symposium DALIAN Future Directions of catalysis Science and Technology October 16-18 2003
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SYNTHESIS OF DIARYL ETHERS THROUGH PHASE TRANSFER CATALYSIS WITH POTASSIUN FLUORIDE COATED ALUMINA AS A STRONG BASE
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作者 Ru Hong KANG Ji Sheng ZHU Wen Zi LI Shu Rong LIU Department of Chemistry,Hebei Normal University,Shijiazhuang 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期55-56,共2页
Seven diaryl ethers were synthesized with potassium fluoride coated alumina as a strong base and the addition of catalytic amount of PTC. The yield of diaryl ethers with addition of PTC was much higher than that witho... Seven diaryl ethers were synthesized with potassium fluoride coated alumina as a strong base and the addition of catalytic amount of PTC. The yield of diaryl ethers with addition of PTC was much higher than that without PTC.A discussion of the catalysis mechanism was given in this paper. 展开更多
关键词 TEBA SYNTHESIS OF DIARYL ETHERS THROUGH PHASE TRANSFER catalysis WITH POTASSIUN FLUORIDE COATED ALUMINA AS A STRONG base PTC AS
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无碱条件下Ru/MgO催化5-羟甲基糠醛氧化并制备高纯度2,5-呋喃二甲酸
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作者 楚国宁 王赛 +2 位作者 马骥 李菁 张爽 《化工科技》 CAS 2024年第4期55-61,共7页
采用煅烧法制备载体MgO,再采用浸渍-还原法制备Ru/MgO催化剂。对催化剂进行表征分析,结果表明,MgO负载Ru后比表面积与碱量增加,Ru作为催化剂活性中心,将Ru/MgO催化剂用于无碱条件下5-羟甲基糠醛(HMF)的选择性氧化,催化活性显著提高。Mg... 采用煅烧法制备载体MgO,再采用浸渍-还原法制备Ru/MgO催化剂。对催化剂进行表征分析,结果表明,MgO负载Ru后比表面积与碱量增加,Ru作为催化剂活性中心,将Ru/MgO催化剂用于无碱条件下5-羟甲基糠醛(HMF)的选择性氧化,催化活性显著提高。MgO在负载Ru后,转换频率(TOF)由2.82×10^(-4) h^(-1)提高至5.98×10^(-1) h^(-1)。Ru/MgO催化剂在最佳反应条件下,HMF转化率为100%,2,5-呋喃二甲酸(FDCA)的产率为95.7%,且在循环使用3次后仍能保持较高的活性,活性组分Ru不易浸出,MgO仅有少量溶解。并采用半制备液相色谱实现产物的绿色分离,最终得到纯度大于99%的FDCA粉末,避免了向体系加入浓盐酸分离出FDCA。该制备方法为无碱体系催化HMF高效合成FDCA提供参考。 展开更多
关键词 Ru纳米粒子 MGO 5-羟甲基糠醛 无碱催化 产物分离 2 5-呋喃二甲酸
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CH_(4)-CO_(2)干重整Ni基催化剂性能调控及应用技术研究进展
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作者 王连英 李洪宝 +3 位作者 辛靖 杨国明 宋宇 陈禹霏 《石化技术与应用》 CAS 2024年第5期389-394,共6页
基于CH_(4)-CO_(2)干重整(DRM)反应的热力学和反应机理,从Ni颗粒尺寸、空间限域结构、形成氧空位和增加活性氧物种等方面综述了避免Ni基催化剂积炭和烧结的调控技术,以及等离子体-催化剂耦合和光热协同催化DRM的应用技术,展望了DRM技术... 基于CH_(4)-CO_(2)干重整(DRM)反应的热力学和反应机理,从Ni颗粒尺寸、空间限域结构、形成氧空位和增加活性氧物种等方面综述了避免Ni基催化剂积炭和烧结的调控技术,以及等离子体-催化剂耦合和光热协同催化DRM的应用技术,展望了DRM技术的发展方向。指出利用可再生电能协同发展等离子体以及光热催化DRM技术具有良好的发展前景。 展开更多
关键词 CH_(4)-CO_(2)干重整 NI基催化剂 积炭 烧结 等离子体 光热催化
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Role of Microstructure and Spectrum Features on the Catalysis Effect of Ce1-x(Nd0.5Eu0.5)xO2-δSolid Solutions
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作者 张国芳 侯忠辉 +2 位作者 翟亭亭 许剑轶 张羊换 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第1期44-54,共11页
Nanosized Ce^1-x)(Nd^0.5)Eu^0.5))xO^2-δ) solid solutions(x = 0.00-0.20) were synthesized by means of hydrothermal method.Then the solid solutions were ball milled with Mg2Ni and Ni powders for 20 h to get the... Nanosized Ce^1-x)(Nd^0.5)Eu^0.5))xO^2-δ) solid solutions(x = 0.00-0.20) were synthesized by means of hydrothermal method.Then the solid solutions were ball milled with Mg2Ni and Ni powders for 20 h to get the Mg2Ni–Ni–5 mol% Ce^1-x)(Nd^0.5)Eu^0.5))xO^2-δ) composites.The structures and spectrum characteristics of the Ce^1-x)(Nd^0.5)Eu^0.5))xO^2-δ) solid solutions catalysts were analyzed systemically.XRD results showed that the doped samples exhibited single phase of CeO2 fluorite structure.The cell parameters and cell volumes were increased with increasing the doped content.Raman spectrum revealed that the peak position of F^2g mode shift to higher wavenumbers and the peak corresponding to oxygen vacancies were observed distinctly for the doped samples.UV-Vis technique indicated that the absorption peaks of Eu^3+ and Nd^3+ ions appeared; the bandgap energy was decreased linearly.The electrochemical and kinetic properties of the Mg2Ni–Ni–5 mol% Ce1-x(Nd0.5Eu0.5xO2-δ composites were measured.The maximum discharge capacity was increased from 722.3 mA h/g for x = 0.00 to 819.7 mA h/g for x = 0.16,and the cycle stability S20 increased from 25.0%(x = 0.00) to 42.2%(x = 0.20).The kinetic measurement proved that the catalytic activity of composite surfaces and the hydrogen diffusion rate were improved for the composites with doped catalysts,especially for the composites with x = 0.16 and x = 0.20.The catalysis mechanism was analyzed from the point of microstructure and spectrum features of the Ce1-x(Nd0.5Eu0.5)xO2-δ solid solutions. 展开更多
关键词 hydrothermal method Ce1-x(Nd0.5Eu0.5)xO2-δ solid solutions Mg2Ni ball milling catalysis mechanism
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Amine-grafted on lanthanide metal-organic frameworks:Three solid base catalysts for Knoevenagel condensation reaction 被引量:6
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作者 任颜卫 陆家贤 +2 位作者 江鸥 程晓飞 陈俊 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1949-1956,共8页
A post-synthetic modification strategy has been used to prepare three solid base catalysts, including Er(btc)(ED)075(H2O)0.25 (2, btc = 1,3,5-benzenetricarboxylates, ED = 1,2-ethanediamine), Er(btc)(PP)0.5... A post-synthetic modification strategy has been used to prepare three solid base catalysts, including Er(btc)(ED)075(H2O)0.25 (2, btc = 1,3,5-benzenetricarboxylates, ED = 1,2-ethanediamine), Er(btc)(PP)0.55(H20)0.45 (3, PP = piperazine), and Er(btc)(DABCO)0.15(H2O)0.85 (4, DABCO = 1,4- diazabicyclo[2.2.2]octane), by grafting three different diamines onto the coordinatively unsaturated Er(III) ions into the channels of the desolvated lanthanide metal-organic framework (Er(otc)). The resulting metal-organic frameworks were characterized by elemental analysis, thermogravimetric analysis, powder X-ray diffraction, and N2 adsorption. Based on its higher loading ratio of the diamine, as well as its greater stability and porosity, catalyst 2 exhibited higher catalytic activity and reusability than catalysts 3 and 4- for the Knoevenagel condensation reaction. The catalytic mechanism of 2 has also been investigated using size-selective catalysis tests. 展开更多
关键词 Lanthanide metal-organic framework Post-synthetic modification Solid base catalystKnoevenagel condensation reaction Size-selective catalysis
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手性三齿Schiff-base配体的合成及其催化的不对称Henry反应研究 被引量:2
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作者 宋庆宝 夏婷 安晓霞 《浙江工业大学学报》 CAS 2014年第1期73-76,共4页
以L-酪氨酸甲酯盐酸盐为原料,通过格氏反应合成了一种手性β-氨基醇;以水杨醛为原料,通过溴代反应合成了3,5-二溴水杨醛和5-溴水杨醛;将手性β-氨基醇和溴代水杨醛在乙醇中缩合,制备了两种手性三齿Schiff-base配体.产物的结构经IR,1 H N... 以L-酪氨酸甲酯盐酸盐为原料,通过格氏反应合成了一种手性β-氨基醇;以水杨醛为原料,通过溴代反应合成了3,5-二溴水杨醛和5-溴水杨醛;将手性β-氨基醇和溴代水杨醛在乙醇中缩合,制备了两种手性三齿Schiff-base配体.产物的结构经IR,1 H NMR,13C NMR和MS表征确定.将配体应用于催化不对称Henry反应中,考察其在不同反应条件下的催化性能,在最优化的反应条件下,不同底物均获得了较好的催化效果,产率最高达95%,ee值最高达90%. 展开更多
关键词 不对称催化 Β-氨基醇 溴代水杨醛 SCHIFF-base Henry反应
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Oxidative coupling of alcohols and amines to an imine over Mg-Al acid-base bifunctional oxide catalysts 被引量:2
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作者 Jinling Song Guiyang Yu +4 位作者 Xi Li Xuwei Yang Wenxiang Zhang Wenfu Yan Gang Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期309-318,共10页
A series of Mg‐Al mixed oxide catalysts are prepared and introduced as efficient irreducible catalysts for the oxidative coupling of alcohols and amines to imine.The structure and surface properties of Mg‐Al oxides ... A series of Mg‐Al mixed oxide catalysts are prepared and introduced as efficient irreducible catalysts for the oxidative coupling of alcohols and amines to imine.The structure and surface properties of Mg‐Al oxides are modulated by changing the Mg/Al ratios,calcination temperature and treatment with probe molecules.Detailed characterization,including X‐ray diffraction,27Al magic angle spinning nuclear magnetic resonance spectroscopy,N2‐adsorption,NH3‐temperature‐programmed desorption,CO2‐temperature‐programmed desorption and X‐ray photoelectron spectroscopy are carried out to determine the physicochemical properties of these catalysts.The Mg‐Al oxides with Mg/Al=3exhibit the highest activity in the reaction,which possess a large number of surface weak basic sites and a relatively small number of weak acidic sites.The role of the acidic and basic sites in the reaction process is systematically investigated,and are shown to serve as adsorption and activation sites for amines and alcohols,respectively.Under the synergistic effect of these acid‐base centers,the oxidative coupling process successfully occurs on the surface of Mg‐Al mixed oxides.Compared with the acidic sites,the weak basic sites play a more important role in the catalytic process.The acidic sites are the catalytic centers for the benzyl alcohol activation,which control the reaction rate of the oxidative coupling reaction. 展开更多
关键词 Oxidative coupling Imine synthesis Alcohol oxidation Mg‐Al mixed oxides Acid‐base catalysis
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Electro-catalytic oxidation of phenol with Ti-base lead dioxide electrode 被引量:1
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作者 王东田 魏杰 +1 位作者 于秀娟 杨红 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第1期19-23,共5页
The Ti base PbO 2 electrode prepared by electrodeposition of PbO 2 on the surface of titanium was used for electro catalytic oxidation of phenol in waste water. The experimental results show that the electrodeposition... The Ti base PbO 2 electrode prepared by electrodeposition of PbO 2 on the surface of titanium was used for electro catalytic oxidation of phenol in waste water. The experimental results show that the electrodeposition of PbO 2 at a higher current density for a short time, then followed by a lower current density can get a compact and combinative PbO 2 layer. The properties of a Ti/PbO 2 electrode with an interlayer of oxide are the best. When this kind of electrode is used to treat phenol containing waste water, the phenol removal rate is higher and the slot voltage is lower. In addition, by using the phenol removal rate as an index, the influences of electrolysis current density, mass transfer condition and pH were studied and the optimal condition was confirmed. 展开更多
关键词 electro catalysis Ti base oxide electrode PHENOL
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A 330-500 GHz Zero-Biased Broadband Tripler Based on Terahertz Monolithic Integrated Circuits 被引量:2
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作者 任田昊 张勇 +4 位作者 延波 徐锐敏 杨成樾 周静涛 金智 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期31-34,共4页
A 330-500 GHz zero-biased broadband monolithic integrated tripler is reported. The measured results show that the maximum efficiency and the maximum output power are 2% and 194μW at 348 GHz. The saturation characteri... A 330-500 GHz zero-biased broadband monolithic integrated tripler is reported. The measured results show that the maximum efficiency and the maximum output power are 2% and 194μW at 348 GHz. The saturation characteristic test shows that the output i dB compression point is about -8.5 dBm at 334 GHz and the maximum efficiency is obtained at the point, which is slightly below the 1 dB compression point. Compared with the conventional hybrid integrated circuit, a major advantage of the monolithic integrated circuit is the significant improvement of reliability and consistency. In this work, a terahertz monolithic frequency multiplier at this band is designed and fabricated. 展开更多
关键词 InP InGaAs A 330-500 GHz Zero-Biased Broadband Tripler based on Terahertz Monolithic Integrated Circuits dBm SBD
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MgO修饰的HZSM-5分子筛对甲苯甲醇烷基化反应性能的影响 被引量:1
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作者 余姮 董焕能 +3 位作者 刘茜桐 胡新瑞 王叶霏 连奕新 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第1期78-84,共7页
采用浸渍法制备了系列MgO修饰的HZSM-5分子筛催化剂,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、NH_(3)程序升温脱附(NH_(3)-TPD)、吡啶红外(Py-IR)等方法对修饰前后的HZSM-5分子筛催化剂进行表征,并在固定床反应器上对催化剂的性能进... 采用浸渍法制备了系列MgO修饰的HZSM-5分子筛催化剂,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、NH_(3)程序升温脱附(NH_(3)-TPD)、吡啶红外(Py-IR)等方法对修饰前后的HZSM-5分子筛催化剂进行表征,并在固定床反应器上对催化剂的性能进行评价.结果表明:MgO的修饰并未对HZSM-5分子筛的晶体结构有明显影响,但是部分MgO优先覆盖了分子筛表面的强酸位,从而降低了分子筛的酸强度,并改变了B酸/L酸比例;同时由于MgO堵塞部分孔道造成分子筛比表面积降低,进一步降低了分子筛表面酸性位的数量,影响甲苯甲醇烷基化反应性能和产物分布.MgO修饰后的HZSM-5分子筛,虽然使甲苯转化率降低,抑制了甲苯歧化反应、深度烷基化反应和缩聚反应的发生,但是有利于对二甲苯和乙基甲苯的生成,表现出一定的择形催化性能. 展开更多
关键词 HZSM-5分子筛 表面修饰 烷基化 酸碱性 择形催化
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Acid-base cooperativity of heterogeneous catalyst containing acidic framework and sterically hindered base for aldol condensation 被引量:1
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作者 Hua Li Shu Tao Xu +1 位作者 Xiao Bing Lu Wei Ping Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1051-1054,共4页
A bifunctional heterogeneous catalyst containing two mutually incompatible acidic and basic sites, which exhibits cooperative catalytic behavior in the aldol condensation of acetone and various aldehydes, was synthesi... A bifunctional heterogeneous catalyst containing two mutually incompatible acidic and basic sites, which exhibits cooperative catalytic behavior in the aldol condensation of acetone and various aldehydes, was synthesized by postgrafting of 1,5,7- triazabicyclo[4.4.0] dec-5-ene (TBD, a sterically hindered organic base) onto AI-MCM-41 molecular sieve. 2009 Xiao Bing Lu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Bifunctional catalyst Acid-base cooperative catalysis Mesoporous material Aldol reaction
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Popping of g-C_3N_4 mixed with cupric nitrate: Facile synthesis of Cu-based catalyst for construction of C-N bond 被引量:1
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作者 Shaoyu Yuan Penglei Cui +3 位作者 Yunrui Zhang Hong Zhang Li Huo Yongjun Gao 《Green Energy & Environment》 SCIE 2018年第4期368-374,共7页
A novel strategy to synthesize copper-based nanoparticles supported on carbon nitride(C3 N4) was developed by popping of mixture containing C3 N4 and cupric nitrate. Characterizations such as X-ray photoelectron spect... A novel strategy to synthesize copper-based nanoparticles supported on carbon nitride(C3 N4) was developed by popping of mixture containing C3 N4 and cupric nitrate. Characterizations such as X-ray photoelectron spectroscopy(XPS) and X-ray diffraction(XRD) indicate that the structure of g-C3 N4 maintained although a popping process occurred. High resolution transmission electronic microscopy(HRTEM) characterization illustrated that copper-based nanoparticles with diameter of < 1 nm were well distributed on g-C3 N4. This kind of copper catalyst exhibits high catalytic activity and selectivity in arylation of pyrazole, a simple and effect strategy to construct C-N bond in organic chemistry.According to the results of control experiments and characterizations, cuprous oxide should be the catalytic active phase in the supported coperbased catalyst. 展开更多
关键词 C-N coupling N-ARYLATION Carbon NITRIDE catalysis COPPER-baseD catalyst
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Synthesis, oxygenation and catalytic performance of manganese complex with p-aminomethyl benzoic acid Schiff base
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作者 刘丰良 李元建 +1 位作者 黄可龙 肖震 《Journal of Central South University of Technology》 EI 2007年第6期793-797,共5页
The amino acid Schiff base complex (Sal-AMBA-Mn) was prepared with p-amino-methylbenzoic acid, salicylaldehyde and Mn(OAc)2·4H2O. Its structures was characterized with IR and UV spectra. Oxygenation mechanism of ... The amino acid Schiff base complex (Sal-AMBA-Mn) was prepared with p-amino-methylbenzoic acid, salicylaldehyde and Mn(OAc)2·4H2O. Its structures was characterized with IR and UV spectra. Oxygenation mechanism of the complex in N, N-dimethylformamide solution was investigated. The results show that lower temperature is in favor of the oxygenation, and energy, enthalpy and entropy are -3.8 kJ/mol, -4.2 J/mol and -161.44 J/(mol·K), respectively. In the presence of the manganese complex, dehydroepiandrosterone acetate is effectively oxidized by molecular oxygen and the corresponding enone 7-ketodehydroepiandrosterone acetate is obtained. The yield is 62.1% when the oxidation is carried out under the reaction conditions of 60 ℃, 2 MPa of O2 pressure, C5H5N as a solvent and molar ratio of the substrate to the complex of 1:10. 展开更多
关键词 amino acid Schiff base manganese complex OXYGENATION catalysis dehydroepiandrosterone acetate aerobic oxidation
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SELECTING CLUSTER MODEL IN Sn - BASED SOLDER ALLOY DESIGN WITH DV - X_α CALCULATION METHOD
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作者 C. Q. Wang and W. F. Feng National ho. of Advanced welding Technolgy, HIT, Harbin 150001,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期84-88,共5页
Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have ... Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail. 展开更多
关键词 Cluster model Sn - based alloy design DV - X_a calculation method DOS
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