La2O3—Ni／SrAl12O19催化剂上甲烷与二氧化碳重整反应的研究

采用ＸＲＤ，ＵＶ－ＤＲＳ，Ｈ２－Ｏ２滴定，ＴＰＲ，吡啶吸附红外光谱等技术，研究了Ｌａ２Ｏ３助剂对Ｌａ２Ｏ３－Ｎｉ／ＳｒＡｌ１２Ｏ１９催化剂的还原性，表面酸性，金属镍的分散度和抗烧结能力，以及对催化甲烷与二氧化碳重整制取合成气反应性能的影响。结果表明，在负载型的镍催化剂中，添加Ｌａ２Ｏ３助剂，能够削弱金属组分与载体之间的相互作用，降低催化剂的还原性，提高金属镍在催化剂表面的分散度和在反应过程中的抗烧     

CH4—H2O—CO2转化制取合成甲醇原料气的研究

在变温床中考查了负载型镍催化剂用于ＣＨ４－Ｈ２Ｏ－ＣＯ２转化制取合成气的活性与稳定性，该过程所制得的合成气勿需分离即可直接用于合成甲醇。本文对催化剂活性下降的原因用比表面、孔结构、ＸＲＤ和ＸＰＳ对不同反应时间的催化剂进行了对比分析，发现镍催化剂活性降低的原因是催化剂表面镍的大量流失。     

CuO／CeO_2／γ－Al_2O_3催化剂的结构及氧物种

应用ＸＲＤ、ＥＳＲ及ＸＰＳ方法研究了ＣｕＯ／ＣｅＯ２／γ－Ａｌ２Ｏ３催化剂的体相及表面结构，并对催化剂表面氧物种进行了表征．实验结果表明，ＣｅＯ２使Ｃｕ２＋还原为低价钢离子和增加钢化合物的分散性．催化剂中ＣｅＯ２含量高时，表面有Ｏ２－和Ｏ－物种，而ＣｅＯ２含量低时，只有Ｏ２－物种．     

丙烷氨氧化V／Sb系复合氧化物催化剂的研究

考察了不同组成的Ｖ－Ｓｂ－Ｏ系复合氧化物对丙烷氨氧化的催化活性。用ＸＲＤ研究了催化剂的结构，利用程序升温方法研究了催化剂中氧的活动性和表面酸碱性，讨论了催化剂体相和表面结构与催化性能间的关系。结果表明，ＶＳｂＯ４和Ｓｂ２Ｏ４间的协同作用是影响催化活性的重要因素。     

SiO2负载的氮化钼催化剂的合成和表征

采用ＭｏＯ３／ＳｉＯ２和ＮＨ３程序升温反应的方法合成了一系列不同Ｍｏ含量的Ｍｏ２Ｎ／ＳｉＯ２催化剂，并采用ＸＲＤ、ＢＥＴ、ＸＰＳ、ＴＰＲ、Ｈ２－ＴＰＤ和ＩＲ等手段，结合中压下吡啶加氢脱氮反应，研究了它们的表面性质和反应性能。发现Ｍｏ２Ｎ／ＳｉＯ２催化剂在反应性能和吸氢性质等方面类似于非负载的氮化钼。氮化前后，低Ｍｏ担载量催化剂的比表面积降低不大，在高Ｍｏ担载量下，由于氮化态的Ｍｏ－ＳｉＯ２催化剂上     

ZrO2在Pd／Al2O3催化剂中的助剂作用

用流动反应法考察了富氧或贫氧气氛中添加ＺｒＯ２的Ｐｄ／Ａｌ２Ｏ３催化剂上ＣＯ的催化氧化反应，并用ＸＲＤ、ＴＰＲ和ＴＰＤ－ＭＳ等技术研究了助剂ＺｒＯ２与γ－Ａｌ２Ｏ３间的相互作用对催化剂上氧物种的还原和脱出－恢复行为的影响，结果表明，基质γ－Ａｌ２Ｏ３与ＺｒＯ２能发生相互作用，添加６％ＺｒＯ２的催化剂氧化活性最好，添加适量的ＺｒＯ２有利于催化剂上氧物种的脱出－恢复，从而促进ＣＯ氧化活性及表面活泼氧物     

甲烷干气重整反应中镍基催化剂上表面积碳研究(英文)

镍基催化剂上积碳是甲烷干气重整反应急需解决的关键问题。实验采用ＴＰＳＲ、ＴＰＤ、ＸＰＳ和脉冲反应等方法系统研究了镍基催化剂表面积碳的形态和特点。热力学研究表明,在５７３ Ｋ到１２７３ Ｋ的温度范围内,催化剂的表面积碳是不可避免的。ＴＰＳＲ、ＸＰＳ和ＴＰＤ研究表明,甲烷在催化剂表面裂解将形成至少三种碳物种：Ｃα、Ｃβ和Ｃγ。这三种碳物种具有不同的表面迁移能力、热稳定性和反应活性。其中,Ｃα物种在甲烷干气重整反应中是一种非常活泼和重要的中间体;Ｃγ物种则可能是表面积碳的前驱物：部分脱氢的Ｃβ物种能够与Ｈ２或ＣＯ２反应生成ＣＨ４或ＣＯ。     

CO2加H2合成甲醇Cu—Zn—O催化剂表面化学态研究

应用ＸＲＤ、ＥＳＲ、ＵＲＤＳ、ＸＰＳ及ＸＡＥＳ等手段研究了ＣＯ２加Ｈ２合成甲醇Ｃｕ－Ｚｎ－Ｏ催化剂在还原后和反应状态下的表面化学状态。结果表明，在还原及反应状态下，催化剂表面仅能检测到ＣＵ＾０，而未发现稳定的Ｃｕ＾２＋和Ｃｕ＾＋存在；ＺｎＯ被 部分还原产生低价锌Ｚｎ＾（２－δ）＋（０＜δ＜２）。关联活性测试结果认为：Ｃｕ＾ｏ／Ｚｎ＾（２－δ）＋Ｏ构成ＣＯ２加Ｈ２合成甲醇反应的活性中心。     

K~＋－SrO－La_2O_3／ZnO催化剂上甲烷氧化偶联反应Ⅱ．催化剂碱性和氧物种的表征

Ｋ＋－ＳｒＯ－Ｌａ２Ｏ３／ＺｎＯ（ＫＳＬＺ）催化体系具有很好的催化活性．在１０７３Ｋ反应温度下，其Ｃ２产率为１８．２％，且Ｃ２选择性为６８．３％．催化剂抗潮能力明显增加，在室温下经长期放置后，催化剂活性稳定．用ＸＲＤ，ＣＯ２－ＴＰＤ和ＸＰＳ表征了ＫＳＬＺ催化剂的体相组成及表面碱性、表面组成和表面活性氧物种．在此基础上讨论了Ｌａ２Ｏ３，ＳｒＯ和Ｋ＋各组分对甲烷氧化偶联反应的作用，提出了表面碳酸盐分解生成活性氧物种的可能性．     

Ga2O3／HZSM—5催化剂的XRD,XPS和TPR研究

利用ＸＲＤ、ＸＰＳ、ＴＰＲ等技术对Ｇａ２Ｏ３／ＨＺＳＭ－５催化剂进行表征，结果表明，催化剂中镓组分以聚集态和分散态的形式存在，其中聚集态中α－Ｇａ２Ｏ３在一定条件下可转化为β－Ｇａ２Ｏ３；分散态又可分为游离Ｇａ２Ｏ３和与ＨＺＳＭ－５产生相互作用的镓组分，催化剂预处理条件及反应一再生过程对镓的分布及状态有较大影响。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.