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11.
Template Reaction of Bis(acetylacetonato)-dioxo-molybdenum(VI) with Benzoylhydrazone By reaction of bis(acetylacetonato)-dioxo-molybdenum(VI) with benzoylhydrazine benzoylhydrazido(2?)-acetylacetonebenzoylhydrazonato(2?)-oxo-molybdenum(VI) was formed beside another species. The compound was characterized by mass spectrometry and X-ray structural analysis. Crystallographic data see ?Inhaltsübersicht”?. 相似文献
12.
分子筛的合成通常是采用含碱金属离子的强碱性体系,通过水热晶化法实现~[1,2]的.得到的分子筛原粉不但必须通过铵离子交换和焙烧才能转变为氢型催化剂,而且在该体系中晶体的粒度也较小.Guth等人~[3]首次报道了在非碱性介质F-离子存在下直接合成铵型ZSM-5的工作.除用四丙基溴化铵合成ZSM-5及其杂原子分子筛外~[4],尚未见到在非碱性介质中合 相似文献
13.
Macrocyclic Lewis acidic hosts with structures incorporating electron-withdrawing icosahedral carboranes and electrophilic mercury centers bind a variety of electron-rich guests. These compounds, the so-called mercuracarborands, are synthesized by a kinetic halide ion template effect that affords tetrameric cycles or in the absence of halide ion templates, cyclic trimers. Both types of mercuracarborands form stable host–guest complexes with anionic and neutral electron-rich molecules. The multidentate structure of mercuracarborand hosts has made these unique molecules ideal for catalytic and ion-sensing applications as well as for the assembly of supramolecular architectures. 相似文献
14.
Summary A computer procedure TFIT, which uses a molecular superposition force field to flexibly match test compounds to a 3D pharmacophore, was evaluated to find out whether it could reliably predict the bioactive conformations of flexible ligands. The program superposition force field optimizes the overlap of those atoms of the test ligand and template that are of similar chemical type, by applying an attractive force between atoms of the test ligand and template which are close together and of similar type (hydrogen bonding, charge, hydrophobicity). A procedure involving Monte Carlo torsion perturbations, followed by torsional energy minimization, is used to find conformations of the test ligand which cominimize the internal energy of the ligand and the superposition energy of ligand and template. The procedure was tested by applying it to a series of flexible ligands for which the bioactive conformation was known experimentally. The 15 molecules tested were inhibitors of thermolysin, HIV-1 protease or endothiapepsin for which X-ray structures of the bioactive conformation were available. For each enzyme, one of the molecules served as a template and the others, after being conformationally randomized, were fitted. The fitted conformation was then compared to the known binding geometry. The matching procedure was successful in predicting the bioactive conformations of many of the structures tested. Significant deviation from experimental results was found only for parts of molecules where it was readily apparent that the template did not contain sufficient information to accurately determine the bioactive conformation. 相似文献
15.
16.
Tamara D. Hamilton 《Journal of solid state chemistry》2005,178(8):2409-2413
We show how a template-controlled reaction performed in the organic solid state can be used to construct a molecule that functions as an organic building unit of both a metal-organic polyhedron and polygon. The template is a small organic molecule that organizes two olefins via hydrogen bonds for a [2+2] photodimerization. The process of utilizing a molecule to build a molecule that is subsequently used for self-assembly is inspired by the general two-step process of template-directed synthesis and self-assembly of Nature that is used to construct large, functional self-assembled structures. 相似文献
17.
通过酸浸和模板合成处理,海泡石直接合成有序介孔二氧化硅和含铝的介孔二氧化硅. 海泡石用盐酸处理后120 ℃下在NaOH溶液中处理72 h, 得到具有HMS结构特征的介孔分子筛;在含铝的碱性溶液中处理后得到具有AlSBA结构的介孔分子筛. 并用SAXRD、BET、TPD表征了介孔分子筛的物相结构、比表面积、孔径分布和表面酸性. 两种介孔分子筛的比表面积分别为508 m2•g-1和946 m2•g-1,孔径分别为3.4 nm和3.9 nm,且孔径分布窄. NH3-TPD结果表明分子筛表面都有两个酸中心,随着Al原子的引入,表面酸性增强. 相似文献
18.
Ibuprofen and ketoprofen are chemically similar non‐steroidal anti‐inflammatory drugs widely used in the treatment of arthritis. Using a molecular imprinting technique, a simple and rapid method was developed for the simultaneous separation and determination of ibuprofen and ketoprofen. Molecular imprinting introduces artificial binding sites into a synthetic polymer matrix, allowing it to exhibit selective rebinding of template molecules. Imprinted polymers can be regarded as an HPLC stationary phase, important for pharmaceutical analysis. Most molecularly imprinted polymers (MIPs) are synthesized by free radical polymerization of functional monomers, resulting in an excess of crosslinking monomers. In this study, MIPs have been prepared with a ibuprofen template, which can form intramolecular hydrogen bonds. Methacrylic acid (MAA) and ethyleneglycol dimethacrylate (EGDMA) were used as the functional monomer and cross‐linker, respectively. Bulk polymerization was carried out at 4 °C under UV radiation. The resulting MIP was ground into 25?44 μm particles, which were slurry‐packed into analytical columns. Template molecules were removed by methanol‐acetic acid (9:1, v/v). We evaluated the template binding performance of the MIP using HPLC, with ultraviolet (UV) detection at 234 nm. Chromatographic resolution of ibuprofen and ketoprofen on the MIPs were appraised using buffer/acetonitrile (45/55, v/v) as the mobile phase. Results show that the MIPs prepared using ibuprofen as the template had a significant molecular imprinting effect. The method was successfully applied to the separation and analysis of ibuprofen and ketoprofen in pharmaceuticals. 相似文献
19.
POROUS MEMBRANE TEMPLATED SYNTHESIS OF POLYMER PILLARED LAYER 总被引:5,自引:0,他引:5
The anodic porous alumina membranes with a definite pore diameter and aspect ratio were used as templates tosynthesize polymer pillared layer structures. The pillared polymer was produced in the template membrane pores, and thelayer on the template surfaces. Rigid cured epoxy resin, polystyrene and soft hydrogel were chosen to confirm themethodology. The pillars were in the form of either tubes or fibers, which were controlled by the alumina membrane pore surface wettability. The structural features were confirmed by scanning electron microscopy results. 相似文献
20.
In this paper,we present a simple method by combining surface wrinkling and template replication to create a series of hierarchical structures on polydimethylsiloxane(PDMS) elastomer.The primary stable lined patterns are formed by duplicating commercialized compact disk and digital versatile disk with PDMS.The secondary microscale patterns are from surface wrinkling,which is elicited by oxygen plasma(OP) treatment of the prestrained PDMS stamp followed with the prestrain release.By systematically varying the OP exposure duration,the prestrain,and the angle(θ) between the primary pattern orientation and the prestrain direction,we obtain highly ordered well-organized composite patterns from different patterning techniques and with different length scales and mechanical stabilities. 相似文献