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Alan G. Macdiarmid Shao-Lin Mu Nanayakkara L.D. Somasiri Wanqun Wu 《Molecular Crystals and Liquid Crystals》2013,570(1-4):187-190
The quinoid-benzenoid-diimine form, (=(C6H4)=N-(C6H4)-N=)x of “polyaniline” shows excellent cathode characteristics including recyclability when used in conjunction with a zinc anode in an aqueous electrolyte of (l. 0M ZnCl2 + 0. 5M NH4Cl) having a pH of ~ 4. The reduced form of this material, (-(C6H4)-N(H)-(C6H4)-N(H)-)x can be used as an anode in conjunction with a Pb02 cathode in an aqueous 0.5M Pb(BF4)2 electrolyte. 相似文献
93.
C. Lavilla A. Alla A. Martínez de Ilarduya E. Benito M.G. García‐Martín J.A. Galbis S. Muñoz‐Guerra 《Journal of polymer science. Part A, Polymer chemistry》2012,50(16):3393-3406
Random poly(hexamethylene terephthalate‐co‐galactarate)s and poly(dodecamethylene terephthalate‐co‐galactarate)s copolyesters covering the whole range of compositions were obtained with weight‐average molecular weights of ~30,000–50,000 g mol?1 by melt polycondensation. They were thermally stable above 300 °C, and displayed Tg in the +20 to ?20 °C range with values steadily decreasing with the content in galactarate units. All the copolyesters were semicrystalline with Tm between 50 and 150 °C and those made from dodecanediol were able to crystallize from the melt at a crystallization rate depending on composition. Copolyesters containing up to 50% of galactaric units retained the crystal structure of their respective polyterephthalate homopolyesters, whereas they adopted the structure of the respective polygalactarates when the content in Galx units reached 70%. Stress‐strain essays revealed decay in the mechanical parameters as the aromatic units were replaced by Galx. Incubation in aqueous buffer revealed that hydrolysis of the polyesters were largely enhanced by copolymerization and evidenced the capacity of the Galx unit for making aromatic polyesters susceptible to biodegradation. A detailed NMR analysis complemented by SEM observations indicated that hydrolysis took place by preferred splitting of galactarate ester bonds with releasing of alkanediol and Galx‐diacid. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Alexandra Muñoz‐Bonilla Gema Marcelo Cintia Casado Francisco J. Teran Marta Fernández‐García 《Journal of polymer science. Part A, Polymer chemistry》2012,50(24):5087-5096
In this article, magnetite nanoparticles (MNPs) coated with glycopolymer bearing glucose moieties were designed with optimal structural, colloidal, and magnetic properties for biomedical applications. MNPs with an average size of 17 ± 2 nm were synthesized by thermal decomposition process and then their surfaces were modified with active vinyl groups. Two different monomers were immobilized onto the surfaces: dopamine methacrylamide, a monomer with properties inspired on mussels adhesive capacity, or unprotected glycomonomer, 2‐{[(D ‐glucosamin‐2N‐yl)carbonyl]‐oxy}ethyl methacrylate. Afterward, the glycomonomer were polymerized at the interface of both vinyl functionalized MNPs by conventional radical polymerization. The resultant hybrid NPs were water dispersible presenting good stability in aqueous solution for long time periods. Moreover, the high density of carbohydrates at the surface of the magnetic NPs could confer targeting properties to the system as demonstrated by studies of their binding interactions with lectins, where the binding activity is higher as the glycopolymer content augments. The magnetic and magneto‐thermal properties of the synthesized hybrid NPs were evaluated. The magnetization curves reveal superparamagnetic features at 300 K, with high values of saturation magnetization. Furthermore, the hybrid glycoparticles show suitable heat dissipation power when exposed to alternating magnetic field conditions. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Ren Y Acuña UM Jiménez F García R Mejía M Chai H Gallucci JC Farnsworth NR Soejarto DD Carcache de Blanco EJ Kinghorn AD 《Tetrahedron》2012,68(12):2671-2678
Six new (1-6) and eight known germacranolide-type sesquiterpene lactones, along with several known phenylpropanol coumarates and methylated flavonoids, were isolated from the leaves of Piptocoma rufescens, collected in the Dominican Republic. The new compounds were identified by analysis of their spectroscopic data, with the molecular structure of 3 being established by single-crystal X-ray diffraction. The absolute configurations of the sesquiterpene lactones isolated were determined from their CD and NOESY NMR spectra, together with the analysis of Mosher ester reactions. Bioassay screening results showed the majority of the sesquiterpene lactones isolated (1-13) to be highly cytotoxic toward the HT-29 human colon cancer cell line, with the most potent compound being 15-deoxygoyazensolide (10, IC(50), 0.26 μM). In addition, several of the sesquiterpene lactones exhibited NF-κB (p65) inhibitory activity. 相似文献
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Margareth S. Alves Jaime E. Muñoz Rivera Mauricio Sepúlveda Octavio P. Vera Villagrán 《Applied Mathematics Letters》2012,25(5):884-889
In this paper we investigate the asymptotic behavior of solutions to the initial boundary value problem for a mixture of two rigid solids modeling temperature and porosity. Our main result is to establish conditions which ensure the analyticity and the exponential stability of the corresponding semigroup. 相似文献