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71.
刘甲顺 《大连理工大学学报》1986,(Z1)
本文介绍了化反对称矩阵为反对称三对角矩阵的Householder方法和Lanczos方法, 以及计算反对称三对角矩阵特征值的低阶算法。讨论了反对称三对角矩阵与对称三对角矩 阵间的关系,提出了反对称三对角矩阵的特征值反问题,并给出了计算方法。 相似文献
72.
73.
烷基季铵盐插层剂的合成及应用 总被引:1,自引:0,他引:1
Three novel intercalation agents were synthesized for the first time, which arose from oleic acid diethylenetriamine or triethylenetetramine 3 - chloro - 2 - hydroxypropy trimethylammonium choride (CHPTA) and chloroethanol. Organophilic vermicullites were synthesized from sodium type vermiculite by cation exchange with new intercalation agents. The results of X - ray diffraction study showed that the gallery distance of the organophilic vermiculite was enlarged from 1 nm to 5 nm or more. A new idea of making design for intercalation agent was provided. 相似文献
74.
XIAO Guang-Can① 《结构化学》2006,(9)
1 INTRODUCTION The construction and characterizations of low dimensional inorganic/organic hybrid materials have increasingly attracted the interest of chemists duo to their unusual topologies and relevance in a wide range of applications in materials science including transport, magnetic materials, catalysts, and lumi- nescent materials[1]. Among the various families of hybrid functional materials, the family of metal halides is an important one. As a branch of the metal halides, silver(… 相似文献
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This study investigates the effect of surface immobilization on the bactericidal function of a quaternary ammonium compound. Quaternary ammonium silane (QAS) coated planar surfaces did not produce any measurable mortality of Staphylococcus aureus, while 1 µm QAS‐coated microparticles did produce S. aureus mortality. The experiments using QAS‐coated microparticles indicate that the ability of QAS molecules to disrupt the cell wall is not hindered by covalent immobilization of QAS to a surface. These results provide evidence that S. aureus cells on a QAS‐coated planar surface are not exposed to a sufficient number of QAS molecules to produce significant mortality. This result has important implications for the development of self‐decontaminating coatings. Covalent immobilization is used to prevent leaching of the bactericidal compound. However, covalent immobilization may result in a significant tradeoff in bactericidal performance. Published in 2007 by John Wiley & Sons, Ltd. 相似文献
77.
0IntroductionConstructionoflow鄄dimensionalorganic鄄inorgan鄄icsupramoleculararrayswithnovelpropertiesrepre鄄sentsnewdirectionsinsolid鄄statechemistry[1,2].Gener鄄allythephysicalpropertiesofsuchlowdimensionalcompoundsdifferfromthoseoftheparentcompound.Our 相似文献
78.
Efficient total syntheses of the herbertane sesquiterpene title compounds have been accomplished employing an Ireland ester Claisen rearrangement and ring-closing metathesis reaction sequence based strategy for the construction of two stereogenic vicinal quaternary carbon atoms on a cyclopentane. 相似文献
79.
环氧丙烯酸酯的紫外光固化 总被引:8,自引:0,他引:8
制备了适于配制紫外光固化涂料的环氧丙烯酸酯,研究了反应温度、阻聚剂、催化剂等因素对环氧树脂与丙烯酸反应的影响;讨论了反应机理和动力学;并利用红外光谱观察了产物的紫外光固化行为。季铵盐能有效地催化环氧树脂和丙烯酸的反应,当其用量为0.6%~1.2%时,在90~110℃反应4.5~8小时后,环氧基转化率大于97%。由此配制的光固化涂料经紫外光辐照能快速固化。 相似文献
80.
One of the major techniques used for the method development of ternary and quaternary high performance liquid chromatography (HPLC) systems has been to use mixture designs, often referred to as "Glajch's Triangle". This technique does not allow for the systematic and simultaneous optimization of other factors such as gradient time, pH and temperature that affect the quality of separations. An alternative approach is to use experimental designs. The condition, however, that the composition of all components of the mobile phase must total 100% presents a problem when trying to mathematically represent ranges of each mobile phase constituent of a ternary or quaternary system. A method is described here, based on spherical coordinate representations, that adheres to the constraints of the mobile phase composition and allows experimental designs, such as central composite and factorial designs, to be applied to the simultaneous optimization of the mobile phase composition. Other factors, in particular temperature and gradient time, can then be included in the design. As a result of applying these designs to the HPLC separation of phenols and corticosteroids, it was found necessary to include three-way interactions between experimental factors in the model. The significance of these interactions shows that they need to be considered in HPLC method development. 相似文献