高岭石插层复合物与纳米高岭石研究现状与展望

某些有机分子可进入高岭石层间形成有机插层复合物,基于高岭石有机插层复合物的功能性材料受到人们的广泛关注并成为当前应用矿物学的研究热点之一。本文介绍了高岭石有机插层复合物与纳米高岭石的研究历史和现状,阐述了高岭石有机插层复合物制备的主要影响因素、插层机理、表征、研究方法以及基于高岭石有机插层作用的纳米高岭石制备,同时对此领域今后的研究方向进行了展望。     

铜材表面化学抛光工艺研究

为满足铜材钝化时对于处理表面的要求,本文系统地研究了多种化学抛光液配方与工艺,并对其中效果较好的两种进行了较深入研究,进而提出了可获得最佳表面抛光效果的配方与工艺．     

应用量子化学算法研究水泥矿物结构与性能的关系

讨论了自洽场离散变分Ｘａ量子化学分子轨道计算方法的基本特性、主要计算结果及其物理意义。评述了ＳＣＦ－Ｘａ－ＤＶ方法在研究水泥矿物结构与性能关系中的应用，研究体系包括硅酸二钙、硫名酸盐铁铝酸盐、铝酸盐、氟铝酸盐、钙钒石及它们的同系物系列。     

高岭石的脱水动力学研究

本文对一定粒级分布的高岭石的脱水反应进行了研究,研究表明高岭石的脱水反应级数与加热速度有关,并首次发现不同温度有不同的脱水量,说明了高岭石的脱水过程是跳跃式的,且其脱水是由水的层间扩散和水的形成共同控制的。     

应用量子化学算法研究水泥矿物结构与性能的关系

讨论了自洽场离散变分X_a（SCF-X_a-DV）量子化学分子轨道计算方法的基本特性、主要计算结果及其物理意义。评述了SCF-X_a-DV方法在研究水泥矿物结构与性能关系中的应用,研究体系包括硅酸二钙、硫铝酸盐、铁铝酸盐、铝酸盐、氟铝酸盐、钙钒石及它们的同系物系列。     

钛酸钡分子核磁共振的量子化学研究

用量子化学从头计算方法，在RHF／LANL2DZ的水平上对单个BaTiO3分子进行了基态构型优化。在此基础上进行了两种规范变换方法（GIAO和CSGT）的RHF／LANL2DZ的NMR屏蔽张量计算，得到与BaTiO3jjj wsg NMR实验研究相符合的结果。     

机械力化学效应对高岭石铝氧多面体的影响

用X射线衍射、红外光谱、魔角旋转-核磁共振、扫描电镜以及盐酸浸取等手段研究了机械力化学效应对高岭石铝氧多面体的影响,并与高岭石的热活化进行了对比。结果表明,机械力化学效应使高岭石的铝氧八面体不断畸变,高岭石最终转变为长程无序的活性物质,这种物质同时存在AlIV、AlV和AlVI三种配位形式,AlVI的含量高于热转变产物偏高岭石。高岭石铝氧八面体中的羟基由于机械力化学效应逐渐脱除,产生的水分子部分以配位和氢键的连接方式存在于活性产物的结构中,其中配位水参与了Al的配位,产生了新的AlVI配位形式[AlO5(H2O)]。[AlO5(H2O)]中的AlVI和[AlO5]中的AlV具有相同的反应活性,高于偏高岭石中以[AlO6]形式存在的AlVI。     

硅烷对高岭石表面选择性修饰制备乳液稳定剂的研究

基于高岭石硅氧四面体和铝氧八面体表面性质的差异,采用乙烯基三甲氧基硅烷( vtms) 对高岭石表面进行选择性修饰,制备高岭石乳液稳定剂,研究其对水/石蜡乳液体系稳定性的影响。结果表明,温度是影响修饰作用的主要因素,在40 ～ 80 ℃,vtms 修饰高岭石的接触角为93° ～ 161°,通过控制修饰温度可以调节高岭石的润湿性。高岭石八面体表面Al-OH 基团与vtms 水解后的Si-OH 基团形成化学接枝。选择性修饰作用提高了高岭石颗粒的极性特征( Janus 效应) ,具有Janus 特征的高岭石具有良好的乳液稳定作用,乳液中乳状液含量达80%,分散相液滴平均粒径为20 μm,且分布均匀,乳液存放90 天后稳定性好。选择性修饰高岭石对乳液类型( 水包油( O/W) 型乳液或油包水( W/O) ) 具有调控作用。     

Quantum Chemistry Calculations on the Interaction Between Kaolinite and Gold

The density function and discrete variation method ( DFT - DVM) is used to study the interaction between kaolinite and gold. The correlation among the structure, chemical bond and stability is discussed. Several models are selected without gold and with gold in different directions and sites . The results show that the models with gold on the edge of kaolinite basal layer are more stable than those with gold above or under the layer, the models ivith gold near to [ A1O2 ( OH)4 ] octahedra are more stable than those with gold near to the vacancy without aluminium. The interaction between gold and the surface ions of kaolinite is strong enough to form the surface complexes.     

Orbital Calculations of Kaolinite Surface:on Substitution of Al~(3 ) for Si~(4 ) in the Tetrahedral Sites

The surface properties of kaolinite were determined using density functional theory discrete variational method(DFT-DVM)and Gaussian 03 program.A SiO_4 tetrahedral hexagonal ring with two Al octahedra was chosen to model the kaolinite crystal.The total density of states of the kaolinite cluster are located near the Fermi level at both sides of the Fermi level.Both the highest occupied molecular orbit (HOMO)and the lowest unoccupied molecular orbit(LUMO)of kaolinite indicate that kaolinite system can not only readily interact with electron-acceptor species,but also readily interact with electron-donor species on the edge surface and the gibbsite layer surface,and thus,shows amphoteric behavior.Substitution of Al~(3 ) for Si~(4 ) in the tetrahedral site linking the vacant Al~(3 ) octahedra does not increase the surface chemical reactivity of kaolinite,while substitution of Al~(3 ) for Si~(4 ) in the tetrahedral site with the apex O linking Al~(3 ) octahedra increase the surface chemical reactivity of the siloxane surface of kaolinite,especially acting as electron donors. Additionally,substitution of Al~(3 ) for Si~(4 ) in the tetrahedral site results in the re-balance of charges,leading to the increase of negative charge of the coordinated O atoms of the AlO_4 tetrahedra,and therefore favoring the formation of ionic bonds between cations and the surface O atoms in the basal plane.     

Reaction Activity of Kaolinite Surfaces：Quantum Chemistry Calculations

The anion-kaolinite surface infractions and AuS - adsorption onto the surfaces of kaolinite were studied using the self-consistent-field discrete variation ( SCF - Xα - DV) method. Electronic structure and energies of the system of anion AuS- adsorbed on an atomic cluster of kaolinite were calculated. The results show that the systems with lower total energy are those AuS- adsorbed on the edge surfaces, which indicates that the systems of adsorption of AuS- on the edges are more stable relative to those adsorbed on the basal plane. On the other hand, bond order data suggest that significant shifting of atomic charge and the overlapping of electronic cloud between Au ( Ⅰ ) of the AuS- and the surface ions of kaolinite would take place in the systems with AuS - being adsorbed on the edges, especially at the she near A1 octahedra. Therqrore, it can be concluded that edge sites will dominate the complexation reactions of the surfaces of kaolinite, with negligible contributions from other fimctional groups on the basal plane, which are dominated by either siloxane sites in silica layers or aluminol sites in gibbsite layers.     

Cr3+在方解石表面吸附的量子化学研究

采用量子化学计算的方法，研究了重金属Cr^3 在方解石表面不同位置吸附时能量的差异。通过对所选用的Cr^3 在方解石表面5个不同位置的模型进行计算，然后对计算结果进行分析，表明当重金属Cr^3 吸附在方解石表面一个CO3^2-侧面的上方时，比重金属Cr^3 在其它位置上发生的吸附更为稳定，同时也说明重金属Cr^3 与方解石表面发生的吸附为配位吸附。     

Reactivity of Tourmaline by Quantum Chemical Calculations

ZnAb initio calculations on reactivity of tourmaline were performed using both Gaussian and density function theory discrete variation method （DFT-DVM）. The HF, B3LYP methods and basis sets STO-3G（3d,3p）,6-31G（3d,3p） and 6-311＋＋G（3df,3pd） were used in the calculations. The experimental results show energy value obtained from B3LYP and 6-31＋＋1G（3df,3pd） basis sets is more accurate than those from other methods. The highest occupied molecular orbital （HOMO） of the tourmaline cluster mainly consists of O atom of hydroxyl group with relative higher energy level, suggesting that chemical bond between those of electron acceptor and this site may readily form, indicating the higher reactivity of hydroxyl group. The lowest unoccupied molecular orbital （LUMO） of the tourmaline cluster are dominantly composed of Si, O of tetrahedron and Na with relative lower energy level, suggesting that these atoms may tend to form chemical bond with those of electron donor. The results also prove that the O atoms of the tourmaline cluster have stronger reactivity than other atoms.     

二氨基苯甲醚稳定性的量子化学研究

对二氨基苯甲醚的六种几何异构体的稳定性差异以及它们的化学反应活性规律从理论上进行了探讨,采用的是量子化学ＭＮＤＯ方法,对六种几何异构体进行全面自由度优化,所得结论为实验提供了有用的理论依据。     

丁酰化甲壳低聚糖化学结构的量子化学计算

利用Gaussian98程序,采用量子化学从头算STO-3G对丁酰化甲壳低聚糖的可能的结构构型进行了全参数优化,并计算出丁酰化甲壳低聚糖各异构体的能量。在此基础上比较了各异构体的稳定性。     

应用量子化学方法研究钙矾石的强度特性

钙矾石相是许多水泥品种的主要水化相之一，对水泥石的强度起着重要作用。本文用量子化学ＳＣＣ－ＤＶ－Ｘａ方法对钙矾石和含锶钙矾石相进行了研究。研究结果表明：两者结构中Ａｌ的键级和Ａｌ—Ｏ键共价键级大致相同。含锶钙矾石中Ｓｒ的键级和Ｓｒ—Ｏ共价键级大于钙矾石中的Ｃａ和Ｃａ—Ｏ键．由此可以认为这是含锶硫铝酸钙水化强度高于硫铝酸酸钙的主要原因之一。     

The Application of SCC-DV-X_a Computational Method of Quantum Chemistry in Cement Chemistry

It has been explored why quantum chemistry is applied to the research field of cement chemistry. The fundamental theory of SCC-DV-Xα computational method of quantum chemistry is synopsized. The results obtained by computational quantum chemistry method in recent years of valence-bond structures and hydration activity of some cement clinker minerals, mechanical strength and stabilization, of some hydrates are summarized and evaluated. Finally the prospects of the future application of quantum chemistry to cement chemistry are depicted.     

聚噻吩掺杂性质的量子化学研究

采用密度泛函理论B3LYP方法,在6—31G基组水平下,对聚噻吩未掺杂体系及其掺杂体系进行了计算,根据几何、前线轨道和原子电荷的计算结果,分析了掺杂剂与聚噻吩链上极子异构区的作用．修正了以前研究工作中不考虑掺杂剂,而认为聚噻吩链上的电子得失是完全的这一缺欠．