镧及其引入方式对锆交联累托土固体酸催化剂性能的影响

摘要：以累托土为基质，采用不同的方式引入La，制备了三种含La的SO4^2-改性锆交联粘土固体酸催化剂．采用XRD，DTA，TG等分析手段对催化剂进行表征，考察了La不同的引入方式对其热稳定性和催化活性的影响．实验结果表明，先用La交换累托土．再与Zr交联剂进行交联．制得的交联粘土的热稳定性显著提高．其DTA谱图上的羟基脱除吸热峰峰温较改性前提高了63℃．500℃焙烧后催化剂仍能保持较规整的层结构．该催化剂用于乙酸和正丁醇的酯化反应能使乙酸转化率达到97．65％．反复再生使用四次后，乙酸转化率仅下降3．83%．     

焙烧温度对SO42-改性锆交联粘土固体酸结构与催化活性的影响

用聚羟基锆离子交换Na基膨润土中的水合钠离子,再引入SO4^2-,在不同温度焙烧制备了锆交联粘土固体酸催化剂,利用XRD,IR,DTA等手段,对该催化剂的结构进行了分析测试,并以柠檬酸和正丁醇酯化反应为探针,考察了焙烧温度对其结构与催化活性的影响。实验结果表明,焙烧温度为500℃时,SO4^2-与锆氧化柱形成了具有超强酸性的结构,催化剂活性较佳,能使柠檬酸酯化反应转化率达96．6％,反应酯化率达95．72％。     

镧锆混合交联蒙脱土的制备和催化性能表征

镧锆混合交联蒙脱土的制备和催化性能表征沐来龙邱金恒颜其洁（南京大学化学化工学院南京２１００９３）金永漱（南京大学现代分析中心南京２１００９３）关键词Ｌａ－Ｚｒ柱交联蒙脱土吡啶吸附氨程序升温脱附甲醇胺化分类号Ｏ６４３．３２层状结构的交联蒙脱土（ＰＩＬＣ...     

[Mo2O4]2+交联层柱粘土的制备及其结构和性能的研究

以[Mo_2O_4]~(2 )溶液为交联剂制备了钼交联层柱粘土。并用XRD、IR、LRS、XPS及TPD等手段对其结构及Mo的存在状态进行了研究。结果表明:[Mo_2O_4]~(2 )被交换进入了层间,所得层柱粘土的d_(?)～13A,其柱结构为Mo_xO_y的簇状氧化物。当交联剂在粘土层间的量超过粘土的交换容量时,Mo在层外表面偏析。酸性研究显示:Mo的加入使钼交联层柱粘土的酸中心数较之原土增加,并以Lewis酸为主。用异丙醇脱水和氧化反应考察钼交联层柱粘土的催化活性,结果表明,这种层柱粘土不仅具有酸催化活性,同时由于钼的引入而具有氧化活性和抗积炭性能。     

有机锆交联剂的制备及其性能

随着油田深部调剖应用的不断推广，以及环保要求的提高，适用于深部调剖调驱体系的低污染有机锆交联剂逐渐受到关注。以ZrOCl₂·8H₂O、乳酸、乙二胺、硫脲为原料，制备了有机锆交联剂和HPAM-锆交联凝胶，其结构和性能经SEM和岩心驱替装置表征。并利用正交实验法优化了制备条件。结果表明：制备有机锆交联剂的最佳条件为：氧氯化锆、乳酸、乙二胺及硫脲的质量比为7.8/1/6.7/5，反应温度为70 ℃，反应时间为3 h。交联温度为60 ℃，HPAM浓度为2 g·L^-1、聚锆比为30/1时，聚合物凝胶成胶强度达到24968 mPa·s，成胶时间约8 h，凝胶体系可维持90 d不破胶。在级差为3.9的双管驱替岩心实验中，两管的岩心分流率均接近50%，剖面改善率达到66.77%。     

锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究Ⅰ丙烯酸酯三元共聚物合成条件对无皂水溶胶性能的影响

三乙醇胺螯合锆烷氧化物;交联反应;锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究 Ⅱ锆螯合物与丙烯酸酯三元共聚物无皂水溶胶的交联反应     

锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究Ⅰ丙烯酸酯三元共聚物合成条件对无皂水溶胶性能的影响

三乙醇胺螯合锆烷氧化物;交联反应;锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究 Ⅱ锆螯合物与丙烯酸酯三元共聚物无皂水溶胶的交联反应     

含铁镍皂石的合成与交联的研究

用水热法合成出铁皂石和铁镍皂石,用羟基铝作交联剂制备了交联粘土.经XRD、DTA、IR、TPR、Mssbauer谱和化学分析表征,证明铁进入了粘土层骨架,铝交联可能作用在四面体铁上.形成Al_p-O-Fe键.     

二溴苯羟基荧光酮荧光光度法测定微量锆

本文提出了一个锆－二溴苯羟基荧光酮（ＤＢＨＰＦ）－乳化剂ＯＰ荧光光度法测定微量锆的新体系，在０．５～１．２ｍｏｌ／Ｌ的ＨＣｌ介质中，锆与ＤＢＨＰＦ生成组化比为１：４的红色荧光性络合物，荧光强度与锆（Ⅳ）的浓度在０～１００μｇ／Ｌ呈线性关系，检出限为２．０μｇ／Ｌ。灵敏度高，高选择性好，用于瓷釉等样品中ＺｒＯ２的测定，获得满意的结果。     

用于锆稳定同位素测定的化学分离技术

本文采用ＨＤＥＨＰ／环己烷体系萃取锆和钼，并将两 发离以便测定锆的稳定同位素，此外，还研究了作为同 素稀释剂的ＺｒＯ２固体粉末的微波溶样法。     

混合金属络合物羟基镍铝交联蒙托土的表面酸性及催化性能

用NH_3-TPD,IR技术研究了混合金属络合物羟基镍铝交联蒙托土的表面羟基和表面酸性。考察了制备方法、Al/Ni比对其表面酸性的影响,同时用异丙苯裂解反应表征了其催化性能。结果表明,交联蒙托土存在L酸和B酸,其中以L酸为主。表面酸性可能来源于柱子和表面羟基,柱子的热稳定性对表面羟基,表面酸性均有较大影响。Ni的引入增加了L酸和B酸,取代法制备的样品具有比共聚法的样品更强的酸性。交联蒙托土具有较好的异丙苯裂解性能,Ni的引入使其活性有较大的增加。     

氧化硅柱层状铁钛酸盐的制备

层柱材料（如层柱粘土、金属磷酸盐等）因其有独特的物理化学性质而倍受人们青睐，并其中；层柱金属氧化物是一类近年来才开发的新型层柱材料．由于制备上的困难，迄今所报导的层柱金属氧化物为数甚少，K0.8Ti1.2O4是一个典型的层状金属氧化物，但由于期没有遇水溶胀性，用常规方法无法制备热稳定的无机氧化物柱层状铁钛酸盐．本文通过先将K0.8Ti1.2O4同n-CH3(CH2)5NH3Cl反应得到正已铵离子柱撑的层状铁钛酸盐，然后再与NH2(CH2)3Si(OC2HO)3（以下简称APS）反应，最后将所得产物在空气中焙烧可得新型氧化硅柱层状铁钛酸盐，该新材…     

对苯乙烯磺酸在水滑石层间的柱撑及聚合

对苯乙烯磺酸在水滑石层间的柱撑及聚合;水滑石;对苯乙烯磺酸;柱撑;聚合     

Structure and Catalytic Activity of Nickel-substituted Mica- montmorillonite Clay Crosslinked with NH2(C3H3)Si(OC2H5)2

Nickel-substituted mica-montmorillonite clays(Ni-SMM) were synthesized, the pillared clays, Si-Ni-SMM, were prepared from the Ni-SMM intercalated with NH2(C3H5)Si(OC2H5)3.The pillar perhaps consists of tripolymer of silica according to the judgement from the pillar height (8. 5A ) data. The results of IR, ESR and XRD indicate that the hydroxy group in the octahedral layer is attacked by crosslinking agent. Thus the silicon oxide pillars become directly linked via oxygen to the nickel atoms in the octahedral layer. The change of the ratio of Lewis to Bronsted acidity on Si-Ni-SMM reduced at 400℃ by H2 shows that the hydrogenating component such as Ni in the framework of SMM plays an important role in catalyst deactivation in H, atmosphere. This kind of action may be due to spilled- over hydrogen.     

Fabrication of Ordered Arrays of Biodegradable Polymer Pincushions Using Self-Organized Honeycomb-Patterned Films

Nano- and micropatterned structures of tissue engineering scaffolds made of biodegradable and biocompatible polymers profoundly influence cell behavior. The present study describes a technically simple and inexpensive method to rapidly fabricate hexagonal arrays of biodegradable polymer pillars (pincushions). As precursors to these polymer pincushion arrays, highly regular porous biodegradable polymer films (self-organized honeycomb-patterned films, called honeycomb films) were prepared on a glass substrate using a simple casting technique. Scanning electron microscope observations revealed that the honeycomb film was composed of a top and bottom layer. This double-layered structure is attributable to the self-organization of hexagonally packed arrays of water droplets that form the template. When we peeled off the top layer of the honeycomb film under ambient conditions using adhesive tape, we obtained arrays of polymer pincushions on both side of the glass substrate and on the adhesive tape. Each air hole is surrounded by six pincushions, each with a diameter of 0.1-1 µm. We also studied factors that determine the morphology of the pincushions, such as the thermal and mechanical properties of the polymers used. It was shown that the heights, widths, and distances of separation between the pincushions could be controlled by the choice of polymer and the pore structure of the original honeycomb film. Such well-ordered, biologically inspired pincushion structures could find application in biomedical, photonic, and electronic materials.     

Tris-N-alkylpyridinium-functionalised cyclotriguaiacylene hosts as axles in branched [4]pseudorotaxane formation

A series of [4]pseudorotaxanes composed of three-way axle threads based on the cyclotriguaiacylene family of crown-shaped cavitands and three threaded macrocyclic components has been achieved. These exploit the strong affinity for electron-poor alkyl-pyridinium units to reside within the electron-rich cavity of macrocycles, in this case dimethoxypillar[5]arene (DMP). The branched [4]pseudorotaxane assemblies {(DMP)₃?L}³⁺,where L = N-alkylated derivatives of the host molecule (±)-tris-(isonicotinoyl)cyclotriguaiacylene, were characterised by NMR spectroscopy and mass spectrometry, and an energy-minimised structure of {(DMP)₃?(tris-(N-propyl-isonicotinoyl)cyclotriguaiacylene)}³⁺ was calculated. Crystal structures of N-ethyl-isonicotinoyl)cyclotriguaiacylene hexafluorophosphate and N-propyl-isonicotinoyl)cyclotriguaiacylene hexafluorophosphate each show ‘hand-shake’ self-inclusion motifs occurring between the individual cavitands.     

A facile method for the synthesis of free-standing pillar[5]arene-based two-dimensional covalent organic monolayers in solution

ABSTRACT

This report describes a facile method by which, without using any surface-assisted growth or pre-organisation, free-standing two-dimensional (2D) covalent organic monolayers (COMs) were synthesised through condensation reactions of planar tri-aldehydes with A1/A2-diamino-substituted pillar[5]arene (DAP5). In the as-formed monolayers (DAP5-COM-1 and DAP5-COM-2), the tubular pentagonal pillar[5]arene units positioned out of the 2D polymer planes suppress efficiently the interlayer π-π stacking interactions. Both DAP5-COM-1 and DAP5-COM-2 can be transferred onto solid surfaces for further characterisation and were found to possess unusual fluorescence up-conversion property.     

Preparation of Barium Titanate with Patterned Microstructure by a Novel Electrophoretic Deposition Method

In order to prepare barium titanate (BaTiO₃) with patterned microstructure, a novel electrophoretic method that uses a partially hydrolyzed highly concentrated solution of barium and titanium alkoxides was developed. By using electron beam lithography, a micro-patterned mold, that is a mold with an array of air holes of 250 nm arranged in a triangular lattice with a lattice constant of 500 nm was prepared on a Pt/Ti/SiO₂/Si substrate. Electrophoretic deposition of BaTiO₃ gel was carried out by negatively biasing the Pt/Ti/SiO₂/Si substrate as cathode which had the resist mold on the surface. Removal of the resist mold left a gel material with a patterned structure that was transferred from the pattern of the mold. The gel material was confirmed by ICP-AES to have nearly the stoichiometric composition of BaTiO₃, that is, a composition in which Ba:Ti = 1:1 in molar ratio.