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91.
环糊精诱导胶束形成的TICT荧光探针法研究   总被引:2,自引:1,他引:2  
环糊精与表面活性剂的相互作用研究已有诸多报导,但主要涉及环糊精与表面活性剂的包络物的稳定常数和其中主客体的化学剂量比[1,2],至于环糊精对表面活性剂胶束化性质的影响则少见涉猎,这或许与研究方法有关,分子内扭转电荷转移激发态涉及到一个完整的电荷转移,具有很高的极性,其荧光特性显示出显著的介质性质敏感性[3],因此将TICT荧光探针法用于环糊精-表面活性剂相互作用研究可能会提供一些新的信息,本文的结  相似文献   
92.
We perform an experimental and theoretical study on some pyrrolyl-izoxazole derivatives with single bridged donor (D) and acceptor (A) moieties, potentially Twisted Intramolecular Charge Transfer (TICT) state forming compounds. The emission spectra in solvent of different polarities and at different excitation wavelengths were performed. The fluorescence quantum yield is very low and the emission band shifts towards long wavelengths in polar solvents and on increasing the excitation wavelength. Solvent dependent semiempirical calculations were performed. The ground and excited states potential energy surfaces were built in terms of the torsion angle about the single bond joining D and A. The ground states have quasiplanar geometry, but the minimum of the excited states corresponds to the orthogonal conformation, stabilised in methanol due to the large charge separation between the D and A fragments. The possibility of forming TICT excited states for the studied pyrrolyl derivatives is discussed.  相似文献   
93.
We consider different types of processes obtained by composing Brownian motion B(t), fractional Brownian motion B H (t) and Cauchy processes C(t) in different manners. We study also multidimensional iterated processes in ? d , like, for example, (B 1(|C(t)|),…, B d (|C(t)|)) and (C 1(|C(t)|),…, C d (|C(t)|)), deriving the corresponding partial differential equations satisfied by their joint distribution. We show that many important partial differential equations, like wave equation, equation of vibration of rods, higher-order heat equation, are satisfied by the laws of the iterated processes considered in the work. Similarly, we prove that some processes like C(|B 1(|B 2(…|B n+1(t)|…)|)|) are governed by fractional diffusion equations.  相似文献   
94.
This work focuses on the synthesis and characterization of porous silica monolith-based adsorbent materials. Materials with bimodal porosity (macro and meso) were prepared through a sol–gel process. The capacity of adsorption of organic molecules was ensured by grafting of hydrophobic organic coating on the silica surface. Alkylsilane chains or lauryl acrylate polymer were used for this purpose. The adsorption kinetic behavior of the produced materials was assessed through benzophenone adsorption studies in aqueous media. The results have shown that the macropore size of the monoliths had no effect on the adsorption capacity. The thicker organic layer prepared by polymerization of lauryl acrylate has decreased the adsorption kinetics without affecting the total adsorption capacity. The over-coating with additional external layer of hydrogel further slowed the diffusion of benzophenone thus better matches the passive-sampler requirements.  相似文献   
95.
96.
A novel hybrid material, (CeIII‐MoVI)Ox/aniline, with rod‐like morphology is synthesized through a wet chemical method using Mo3O10(C6H5NH3)2.2H2O nanowires as precursor. The synthesized materials are characterized by XRD, XPS, SEM, TEM, FTIR, Raman, UV–Vis, TGA, and elemental analysis. Also, their catalytic activities as a hybrid catalyst are tested in the selective oxidation of sulfides using hydrogen peroxide as a green oxidant. The proposed novel hybrid catalyst shows an excellent performance under green conditions at mild temperature. Furthermore, the scalability of the oxidation reaction is shown by making multi‐gram quantities at optimized conditions.  相似文献   
97.
A planar rod model with flexible cross-section has been recently proposed in literature (Guinot et al., 2012). This model is especially suitable for the modeling of tape springs, which develop localized folds due to the flattening of the cross-section. Starting from a complete non-linear elastic shell model, original kinematics assumptions (inspired from the elastica model) have been made to describe the important in-plane changes of the cross-section shape. In the present work, the choice of the position of the rod reference line is discussed. This choice plays an important role in the overall behavior because of the large changes of the cross-section shape. We show that the model published in Guinot et al. (2012) can be improved by considering the centerline as the rod reference line. This enhanced model is then validated through quantitative comparisons with experimental results of dynamic deployments taken from literature.  相似文献   
98.
This paper presents a treatment of material symmetry for hyperelastic rods. The rod theory of interest is based on a Cosserat (or directed) curve with two director fields, and was developed in a series of works by Green, Naghdi and several of their co-workers. The treatment is based on Murdoch and Cohen's work on material symmetry of Cosserat surfaces. Two material symmetry groups are discussed: one pertains to the strain-energy function, while the other pertains to the response functions. The paper closes by showing how the treatment relates to the form-invariant approach used in Green and Naghdi's papers and a treatment proposed recently by Cohen. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
99.
In this paper we consider the transfer of the property of being a left Goldie ring between a ring A and its partial crossed product A*α G by a twisted partial action α of a group G on A.  相似文献   
100.
Large‐scale submicron gallium oxide hydrate (GaOOH) rods have been synthesized by a simple hydrothermal process and their optical, electrochemical properties have been analyzed. The diameter of the GaOOH nanorods with good single crystalline structure is 80‐800 nm and length of less than 4 μm. The tips of the GaOOH structures are composed of nanorods with the diameter of less than 10 nm and length of more than 100 nm. Hydrothermal temperature, time and the Ga‐contained starting materials have important roles on the formation and growth of submicron GaOOH rods. The submicron GaOOH rods exhibit good UV‐vis absorption ability. The electrochemical analysis shows that the submicron GaOOH rods have good detecting ability for ascorbic acid and cysteine in PBS and NaCl solution exhibiting promising potential for electrochemical sensing application. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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