煤系高岭土热化学反应动力学

煤系高岭土的热化学反应包括高岭土的脱羟与反应与煤的燃烧反应。利用程序升温热分析法得到几种煤系高岭土样品的ＴＧ／ＤＴＧ谱图，由Ｆｒｅｅｍａｎ－Ｃａｒｒｏｌｌ法计算出煤系高岭土势化学反应的动力学参数。     

离子交换蒙脱石脱水过程研究

用ＤＴＡ，ＴＧ，ＸＲＤ以及ＴＰＤ－ＧＣ等方法系统地研究了一组金属离子交换蒙脱石的脱水过程。研究表明，离子交换蒙脱石中吸附水的存在状态和数量明显地依赖于其可交换金属阳离子的水合能力和交换数目。在５０─３００℃温区范围内，离子交换蒙脱石ＤＴＡ曲线上第一吸热峰是由吸附水的脱出所造成的，而第二吸热峰则主要是由其晶格收缩调整所引起的，蒙脱石中吸附水的脱出对第二吸热峰的贡献很小。     

均匀棒状过氧化合碳酸钠制备及非等温热分解动力学

本文制备了均匀棒状过氧化氢合碳酸钠，化学分析确定其组成为Ｎａ２ＣＯ３·１．５Ｈ２Ｏ２，用ＤＴＡ－ＴＧ－ＤＴＧ技术并辅以Ｘ－ｒａｙ分析研究了它在静态空气、流动氧气和流动氮气气氛中的非等温热分解过程及动力学。     

γ—Mo2N合成过程中的热变化及中间产物的研究

采用ＤＴＡ技术，通过改变升温速率研究了γ－Ｍｏ２Ｎ合成过程中的热变化，并经ＸＲＤ，ＢＥＴ及ＩＲ测试，对ＤＴＡ曲线中的谱峰进行归属，考察了中间产物，ＤＴＡ结果表明，在ＭｏＯ３和ＮＨ３程序升温反应过程中有放热峰及吸热峰出现，且随升温速率的长高，放热峰面积与吸热峰面积之比逐渐减小，结合ＸＲＤ及ＩＲ结果可知，ＤＴＡ曲线听放热峰可归属为由ＭｏＯ３变化为ＭｏＯ２的还原峰，吸热峰则归属为由ＭｏＯ２变化为Ｍｏ２Ｎ     

煅烧煤系高岭土粒度分布的分形特征

通过分析煤系高岭土及其煅烧产物的粒度,得出：煤系高岭土的粒度分布具有分形规律,同时发现煤系高岭土的普度变化包括膨胀阶段和收缩阶段,并且与高岭土的结构变化相关,计算不同煅烧温度的煅烧产物的粒度分布分维数,并得出分维数与煅烧的关系曲线,由此关系曲线可较容易地确定出煤系高岭土的煅烧温度。     

不同pH值下合成的双中孔和六方中孔SiO_2的表征(英文)

在相同的反应体系中当ｐｈ值从约９．５调变至１１时分别合成出双中孔ＳｉＯ２和六方中孔ＳｉＯ２材料,并用ＸＲＤ、Ｎ２吸附、ＴＥＭ、ＴＧ／ＤＴＡ和ＦＴＩＲ等测试手段对合成产物进行了表征。实验结果表明,双中孔ＳｉＯ和六 方中孔ＳｉＯ２是合成中必然出现的两种不同的中孔物相。与六方中孔ＳｉＯ２相比,双中孔ＳｉＯ２也具有典型中孔 材料的特征ＸＲＤ谱图,虽然仅呈现一个易让人产生不完全晶化误解的相对较宽的单ＸＲＤ衍射峰（ｄ＝５．２ｎｍ）,但它却给出一种独特的Ｎ２吸附等温线和窄的双峰中孔孔径分布曲线。由于孔壁的无定形及表面活性剂分子与ＳｉＯ２骨架间相似的相互作用,两类材料给出类似的ＦＴＩＲ谱图和ＴＧ／ＤＴＡ曲线。然而,在双中孔ＳｉＯ２的ＦＴＩＲ谱图中９６０ｃｍ处峰强度的微小变化可能意味着在锻烧脱除模板剂后双中孔ＳｉＯ２较六方中孔ＳｉＯ２具有更高的骨架聚合度。     

侧基上带有C60基因的聚苯乙烯的表征

用ＵＶ、ＦＴＩＲ、ＤＳＣ、ＴＧ和ＤＴＡ及ＧＰＣ等方法证明了通过三步反应（氯甲基化，叠氮化，环加成反应）确实将Ｃ６０引入到聚苯乙烯的侧基上，Ｃ６０基本上以单取代的方式存在，并通过ＴＧ和ＤＴＡ方法估算了Ｃ６０在聚苯乙烯Ｃ６０衍生物中的含量。     

水合溴化镧的脱水动力学及与二甲基亚砜配合物的合成和热分析…

合成了水合溴化镧和溴化镧与二甲基亚砜的配合物，经化学分析和红外光谱确定基组成分别为ＬａＢｒ．３７Ｈ２Ｏ和ＬａＢｒ３．７ＤＭＳＯ．应用ＴＧ－ＤＴＡ－ＤＴＧ联用技术研究了水合盐的脱水过程；由ＤＴＡ法测得脱水焓值。依据ＴＧ、ＤＴＡ数据进行了动力学分析。求出了第一、第二阶段脱水反应的活化能并推断出脱水反应机理。用相同的技术研究了ＬａＢｒ３．７ＤＭＳＯ的热分解过程。     

水合溴化镧的脱水动力学及与二甲基亚砜配合物的合成和热分析研究

合成了水合演化镧和演化镧与二甲基亚砜（ＤＭＳＯ）的配合物，经化学分析和红外光谱确定其组成分别为ＬａＢｒ３．７Ｈ２Ｏ和ＬａＢｒ３·７ＤＭＳＯ。应用ＴＧ－ＤＴＡ－ＤＴＧ联用技术研究了水合盐的脱水过程；由ＤＴＡ法测得脱水焓值。依据ＴＧ、ＤＴＡ数据进行了动力学分析。求出了第一、第二阶段脱水反应的活化能并推断出脱水反应机理。用相同的技术研究了ＬａＢｒ３·７ＤＭＳＯ的热分解过程。     

SELECTIVE DIMERIZATION OF BUTANAL TO BUTYL BUTYRATE CATALYZED BY LANTHANOCENE／n－BuLi SYSTEMS

ＳＥＬＥＣＴＩＶＥＤＩＭＥＲＩＺＡＴＩＯＮＯＦＢＵＴＡＮＡＬＴＯＢＵＴＹＬＢＵＴＹＲＡＴＥＣＡＴＡＬＹＺＥＤＢＹＬＡＮＴＨＡＮＯＣＥＮＥ／ｎ－ＢｕＬｉＳＹＳＴＥＭＳ￥ＦａｎＸＵ，ＬｉＬｕＺＨＡＮＧ，ＭｉｎｇＹＡＯ，ＹｕａｎＣｈｅｎＤＩＮＧ，ＺｈｉＭｉ...     

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.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

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.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.