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1.
The synthesis and characterization of a novel polythiophene substituted with a 2′‐pentyloxy‐5′‐(1″′‐oxooctyl) phenyl group (PPOPT) is reported. The bulk transport properties of thin films of PPOPT are investigated by admittance spectroscopy. The dramatic effect of the phenyl side chain on the mobility of positive carriers in films of PPOPT is described. The photophysics of PPOPT in both solution and thin film is also investigated and correlated to substituent‐driven intrachain and interchain arrangements. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   
2.
Methodologies for the immobilization and characterization of ruthenium complexes into/onto functionalized silica gel, zeolites, polymers, dendrimers, sol–gel, nano and microparticles are described. The corresponding spectroscopic, electrochemical, and photochemical properties as well as chemical reactivities are used for their characterization and study. Comparison between the reactivities of immobilized and in solution species is presented. Some biological applications are also described.  相似文献   
3.
Expanding the repertoire of controlled radical fluorination techniques, we present a photosensitized unstrained C–C bond activation/directed monofluorination method using Selectfluor and 9-fluorenone. The reaction is amenable to the opening of multiple 1-acetal-2-aryl substituted rings to yield ω-fluoro carboxylic acids, esters, alcohols, and ketones with relative ease. Initial mechanistic insight suggests radical ion intermediates.  相似文献   
4.
In this paper, we considered the model of the thirteenth order derivatives of nonlinear Schr\"{o}dinger equations. It is shown that a wave packet ansatz inserted into these equations leads to an integrable Hamiltonian dynamical sub-system. By using bifurcation theory of planar dynamical systems, in different parametric regions, we determined the phase portraits. In each of these parametric regions we obtain possible exact explicit parametric representation of the traveling wave solutions corresponding to homoclinic, hetroclinic and periodic orbits.  相似文献   
5.
This paper study the traveling wave solutions of the Casimir equation for the Ito system. Since the derivative function of the wave function is a solution of a planar dynamical system, from which the exact parametric representations of solutions and bifurcations of phase portraits can be obtained. Thus, we show that corresponding to the compacton solutions of the derivative function system, there exist uncountably infinite kink wave solutions of the wave equation. Corresponding to the positive or negative periodic solutions and homoclinic solutions of the derivative function system, there exist unbounded wave solutions of the wave function equation.  相似文献   
6.
The Prins reaction, an acid‐catalyzed condensation of alkenes with aldehydes, is used extensively in the fragrance industry. This year we celebrate the 100th anniversary of the discovery of this reaction. In honor of this occasion we present an overview of the diverse applications of the Prins reaction in the synthesis of flavor and fragrance ingredients. To pay tribute to the inventor of the Prins reaction, Hendrik Jacobus Prins, we also provide some insight into his life, scientific, and entrepreneurial accomplishments.  相似文献   
7.
Ruthenium complexes including nitrosyl or nitrite complexes are particularly interesting because they can not only scavenge but also release nitric oxide in a controlled manner, regulating the NO-level in vivo. The judicious choice of ligands attached to the [RuNO] core has been shown to be a suitable strategy to modulate NO reactivity in these complexes. In order to understand the influence of different equatorial ligands on the electronic structure of the Ru-NO chemical bonding, and thus on the reactivity of the coordinated NO, we propose an investigation of the nature of the Ru-NO chemical bond by means of energy decomposition analysis (EDA), considering tetraamine and tetraazamacrocycles as equatorial ligands, prior to and after the reduction of the {RuNO}(6) moiety by one electron. This investigation provides a deep insight into the Ru-NO bonding situation, which is fundamental in designing new ruthenium nitrosyl complexes with potential biological applications.  相似文献   
8.
The effect of soft segment component and molecular weight combination on moisture‐permeable polyurethane films was studied. Moreover, water sorption phenomenon in films was observed with infrared analysis. As for soft segment components, PTMG/PEG and PTMG/PPG were used and molecular weight combinations were changed. Different tendency appeared in the experimental results corresponding to PEG system and PPG system. Moisture permeability P in PEG system increased with increasing PEG content, but P changed little in the case of PPG system. Both hydrogen‐bonded concentration by infrared measurement and the higher order term Δh of Mooney–Rivlin plot by stress–strain relationships indicate the existence of aggregate structure of hard segment. It is considered that ether group in PEG is more active than that in PPG. Therefore, small size of aggregate structure indicated as Δh appears in PEG system owing to inhibition of aggregate structure growth. Whereas, ether group in PPG system does not inhibit hydrogen bond in urethane group and large size of aggregate structure appears. From water affinity relationship analysis, hydrophilicity of samples with PTMG/PEG = 2000/2000 increased with increasing PEG content. Consequently, it is suggested that not only size but also hydrogen‐bonded concentration of urethane group in aggregate structure affects moisture permeability. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 573–583, 2006  相似文献   
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