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361.
Farida Benmouna Samira Zemmour Mustapha Benmouna 《Journal of Macromolecular Science: Physics》2016,55(3):319-329
Structural properties and phase behavior of crosslinked networks embedded in polymer solutions are theoretically investigated. The partial structure factor of the network is calculated using a matrix formulation of the random phase approximation and the forward scattering limit is correlated with the phase behavior. Swelling and deswelling processes are analyzed in terms of the polymer concentration, the mismatch of solvent quality with respect to polymer and network, the polymers incompatibility and their characteristic sizes. Most studies reported so far in the literature have focussed on the swelling of crosslinked networks and gels in pure solvents but the correlation of the structural properties with the phase behavior in the presence of high molecular weight polymers in solution has not been given sufficient attention. The present work is intended to fill this gap in view of the current efforts to develop novel drug encapsulating and targeted delivery devices. 相似文献
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This paper is devoted to the equilibrium shapes of rotating liquid drops. Families of axisymmetric shapes are found using a perturbation technique for the governing nonlinear equation. Bifurcation and turning points are located by applying a special type of Hermite–Padé approximation. 相似文献
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366.
Abdellatif El Kihel Mustapha Ahbala Abdelkrim Mouzdahir Naima Snader El Mokhtar Essassi Patrick Bauchat 《合成通讯》2013,43(2):200-204
Imidazobenzodiazepine derivatives were obtained by cyclization of the condensation products 7‐amino‐2,5,6‐trimethylbenzimidazole with acetylacetone and ethyl acetoacetate. By careful examination of spectroscopic data and the open‐chain intermediate isolation, we have identified the formed compound structure. 相似文献
367.
Ghenia Bentabed Mustapha Rahmouni Florence Mongin Aicha Derdour Jack Hamelin 《合成通讯》2013,43(17):2935-2948
Abstract Cycloadditions of aldehydes with carbonyl ylides to give dioxolanes have been carried out without solvent under microwave irradiation. The reactions proceeded in similar yields and stereoselectivities, but in shorter reaction times, than those obtained in toluene at reflux using an oil bath. Cycloadditions conducted between imines and carbonyl ylides using the same protocol were less efficient because the oxazolidines formed proved unstable under the reaction conditions. 相似文献
368.
A new procedure for the ring opening of 4,6-O-benzylidene acetals of carbohydrates with N-bromosuccinimide using calcium carbonate in stoechiometric amount instead of excess barium carbonate is described. This procedure is successfully applied to some highly functionnalized substrates without side reactions. 相似文献
369.
Chemical investigation of an endophytic fungus, Pestalotiopsis theae, isolated from the leaves of Turraeanthus longipes (Meliaceae) collected in Cameroon, resulted in the isolation of six new epoxyquinols, cytosporins F–K (2–7), together with the known cytosporin D (1). The structures of the new compounds were unambiguously determined by analysis of the 1D, 2D NMR, and HRMS spectra. Cytosporins G–K (3–7) are the first cytosporins with a hydroxyl substituted C7 side chain, while cytosporins F–I (2–5) contain a 13-acetoxyl group that was not reported previously. A plausible biosynthetic pathway for the cytosporin derivatives is proposed. 相似文献
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