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排序方式: 共有41条查询结果,搜索用时 7 毫秒
1.
本文报道了一类长链烷氧取代金属卟啉化合物3的合成.研究了由化合物3与表面活性剂:十二烷基三甲基溴化铵所形成的混合胶束体系作为仿细胞色素P-450加氧酶模拟物对苯乙烯环氧化的催化活性.结果表明:在胶束体系中长链烷氧取代金属卟啉的催化效率优于对称四甲苯基金属卟啉,由此证实:混合胶束中,疏水内核提供的模拟酶的疏水微环境,在苯乙烯环氧化反应中起着重要作用.  相似文献   
2.
EMG模型参数间的联系   总被引:3,自引:0,他引:3  
何大森  李似姣 《化学学报》1990,48(7):673-677
通过色谱拖尾峰EMG数学模型的计算机数值计算, 建立了拖尾峰特征参数之间的三类不同性质的线性关系, 佐证并修正了一些经验公式, 提出了计算模型参数与保留时间之间线性关系的新方法。  相似文献   
3.
We give a general Hamiltonian formulation of the Friedmann-Robertson-Walker (FRW) fundamental equations of a homogeneous and isotropic universe in the Standard Cosmological model. It gives some interesting insight on the 3-curvature of the universe, which is found to be obtained in terms of the scale factor (also termed radius of the universe) and its first derivative. It also leads to an easy determination of the Schrödinger equation for the (R) wave function of the universe, in the radiative era.  相似文献   
4.
《Composite Interfaces》2013,20(7):557-573
Using in-situ emulsion polymerization, the exfoliated nanocomposites were prepared from vinyl acetate (VAc) and organic montmorillonite (OMMT) through five different experimental conditions. The different experimental conditions and OMMT had little effect on the structure of PVAc–OMMT, but significant effect on the dynamic mechanical properties. They produced a combined effect on the modulus, loss tangent and glass transition temperature (T g). OMMT could lower T g of PVAc, and improved PVAc's low temperature resistance. PVAc and PVAc–OMMT all were homogeneous amorphous linear polymers and they all displayed cold crystallization. The different experimental conditions and OMMT had some effects on the thermal degradation. The thermal degradation process was found to consist of eight phases, and those of PVAc and PVAc–OMMT were similar. OMMT had no obvious effect on the thermal degradation temperature, but mainly delayed the thermal degradation process.  相似文献   
5.
汪绍昆 《化学学报》1994,52(6):729-737
提出一种半经验的关联-预测活度系数的系统。二元系的活度系数用一过量自由焓模型推算。该模型的模型参数从2个代数方程联立求解, 其一关联模型参数与γ^∞, 另一关联模型参数与(dγ-dx)x=0。γ^∞用MOSCED模型由纯组分性质关联。(dγ/dx)x=0用三维溶解度参数关联。用该系统对145组等温极性二元系作了预测, 对计算结果与实验值作了对比。F0T6R19  相似文献   
6.
We have shown recently that the gravity fieldphenomena can be described by a traceless part of thewave-type field equation. This is an essentiallynon-Einsteinian gravity model. It has an exactsphericallysymmetric static solution, that yields to theYilmaz-Rosen metric. This metric is very close to theSchwarzchild metric. The wave-type field equation cannotbe derived from a suitable variational principle by free variations, as was shown by Hehl and hiscollaborators. In the present work we are looking foranother field equation having the same exactspherically-symmetric static solution. Thedifferential-geometric structure on the manifold endowed with a smoothorthonormal coframe field is described by the scalarobjects of anholonomity and its exterior derivative. Weconstruct a list of the first and second order SO(1,3)-covariants (one- and two-indexedquantities) and a quasi-linear field equation with freeparameters. We fix a part of the parameters by acondition that the field equation is satisfied by aquasi-conformal coframe with a harmonic conformal function .Thus we obtain a wide class of field equations with asolution that yields the Majumdar-P apapetrou metricand, in particular, the Yilmaz-Rosen metric, that is viable in the framework of three classicaltests.  相似文献   
7.
《Analytical letters》2012,45(5):459-469
Abstract

The enantiomeric purity of a series of polyester model compounds has been assayed by NMR spectroscopy, using chiral lantha-nide shift reagents. The dependencc of proton and 13 C NMR spectra on concentration and temperature has been investigated.  相似文献   
8.
金属胶束超分子体系研究新进展   总被引:3,自引:0,他引:3  
综述了近年来金属胶束超分子体系的研究新进展,着重介绍了本科研组应用金属胶束超分子体系模拟羧肽酶A、磷酸酯水解酶、细胞色素P-450等方面的研究成果。并对建立金属胶束超分子体系的动力学处理模型及催化水解反应的机理进行了讨论。  相似文献   
9.
杯芳烃化学的研究   总被引:4,自引:0,他引:4  
黄志镗  郑企雨 《有机化学》2001,21(11):904-913
杯芳烃作为超分子化学研究中一类重要的人工合成受体分子已受到广泛的关注,在化学、生物以及材料领域内显示出巨大的研究和应用前景。本文首先综述了杯芳烃在分子识别、模拟酶及分子自组装等方面的最新研究进展,然后介绍了作者从事杯芳烃研究十余年所取得的成果。  相似文献   
10.
The dynamic theological measurements have been a preferred approach to the characterization of the structure and properties for multi-component or multi-phase polymer systems, due to its sensitive response to changes of structure for these heterogeneous polymers. In the present article, recent progresses in the studies on dynamic theology for heterogeneous polymer systems including polymeric composites filled with inorganic particles, thermo-oxidized polyolefins, phaseseparated polymeric blends and functional polymers with the scaling and percolation behavior are reviewed, mainly depending on the results by the authors‘ group. By means of theological measurements, not only some new fingerprints responsible for the evolution of morphology and structure concerning these polymer systems are obtained, the corresponding results are also significant for the design and preparation of novel polymer-based composites and functional materials.  相似文献   
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