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121.
Paula C. Barbosa Luísa C. Rodrigues Maria Manuela Silva Michael J. Smith Prudência B. Valente Alexandra Gonçalves Elvira Fortunato 《先进技术聚合物》2011,22(12):1753-1759
Solid polymer electrolyte (SPE) systems based on interpenetrating blends of poly(ethylene oxide‐co‐propylene oxide) and poly(methyl methacrylate) host matrices, with lithium perchlorate as guest salt, were prepared. These electrolytes were presented as free‐standing films, and their thermal and electrochemical properties were characterized by conductivity and electrochemical stability measurements. The properties of the interpenetrating blends of poly(ethylene oxide‐co‐propylene oxide) and poly(methyl methacrylate) host matrices as the electrolyte component of a solid‐state electrochromic device are reported and the results obtained suggest that this electrolyte provides an encouraging performance in this application. The most conducting electrolyte composition of this SPE system is the formulation designated as SPE2‐0PC (5.01 × 10?4 S cm?1 at about 57°C). The lowest decomposition temperature was registered with the SPE6‐15PC composition (233°C). The average transmittance in the visible region of the spectrum was above 41% for all the samples analyzed. After coloration the device assembled with 71 wt% PC presented an average transmittance of 15.71% and an optical density at 550 nm of 0.61. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
122.
C. B. Ferreira M. Fernandes L. C. Rodrigues M. M. Silva M. J. Smith V. de Zea Bermudez 《Ionics》2013,19(12):1803-1809
The present study has been focused on environmentally friendly sol–gel-derived electrolytes based on a di-urethane cross-linked d-PCL(530)/siloxane network [where d represents di, PCL identifies the poly(ε-caprolactone) biopolymer, and 530 is the average molecular weight in grams per mole] doped with a wide range of concentration of lithium perchlorate and lithium bis(trifluoromethanesulfonyl)imide. Fourier Transform Infrared and Raman spectroscopies have been applied to evaluate the extent of ionic association. Characteristic bands of the PCL(530) segments, of the urethane cross-links, and of the anions have been examined to gain insight into the cation/biopolymer, cation/anion, and cation/cross-link interactions. In both electrolyte systems, “free” ions and contact ions have been identified. The addition of salt modifies the hydrogen-bonded array of the host matrix, causing the destruction/formation of the urethane/urethane aggregates. 相似文献
123.
Anna Maria Deobald Greice Tabarelli Oscar E.D. Rodrigues Antônio L. Braga 《Tetrahedron letters》2010,51(26):3364-3367
We present here our results of the efficient synthesis of azido arylselenides and azido aryldiselenides under mild conditions. Starting from nitrogen-substituted benzenes, we incorporated selenium atom at aromatic ring and obtained amino arylselenides and diselenides in satisfactory yields. Treatment of these compounds with iso-pentyl nitrite (i-C5H11ONO) and azido trimethylsilane (Me3SiN3) in THF affords a variety of azido arylselenides and diselenides in good to excellent yields. 相似文献
124.
Roberto Laridondo Lui Daniel Rodrigues Blanco Vladimir Pavan Margarido Orlando Moreira Filho 《Micron (Oxford, England : 1993)》2009,40(5-6):552-559
B chromosomes are considered additional and non-essential; they likely originate from A chromosomes and follow a distinct evolution. In fish, approximately half of the Neotropical species with B chromosomes are Characiformes and 35% are Siluriformes. There has been no report of B chromosomes in Auchenipteridae until this moment. B chromosomes found in a population of Parauchenipterus galeatus from the São Francisco River basin in the state of Minas Gerais (Brazil) were small, metacentric, totally heterochromatic and exhibited intra-individual and inter-individual variation. The diploid number was 58 chromosomes (22 metacentric, 16 submetacentric, 12 subtelocentric and 8 acrocentric). The nucleolar organizing regions were simple and the heterochromatin intercalated in the ribosomal sites, characterized by CMA3 and DAPI fluorochromes, was of a GC-rich constitution. The 5S rDNA genes were located in an intercalary position in only one chromosome pair. An hypothesis about the origin of the B chromosomes in P. galeatus and a review on B chromosomes in catfish are also presented in this study. 相似文献
125.
Namkwon Kim Luisa Consiglieri Jos Francisco Rodrigues 《Mathematical Methods in the Applied Sciences》2006,29(13):1523-1541
A modified model for a binary fluid is analysed mathematically. The governing equations of the motion consists of a Cahn–Hilliard equation coupled with a system describing a class of non‐Newtonian incompressible fluid with p‐structure. The existence of weak solutions for the evolution problems is shown for the space dimension d=2 with p? 2 and for d=3 with p? 11/5. The existence of measure‐valued solutions is obtained for d=3 in the case 2? p< 11/5. Similar existence results are obtained for the case of nondifferentiable free energy, corresponding to the density constraint |ψ| ? 1. We also give regularity and uniqueness results for the solutions and characterize stable stationary solutions. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
126.
127.
S. Sofia M. Rodrigues Dr. David S. M. Ribeiro Dr. Christian Frigerio Susana P. F. Costa Prof. Dr. João A. V. Prior Dr. Paula C. A. G. Pinto Prof. Dr. João L. M. Santos Prof. Dr. M. Lúcia M. F. S. Saraiva Dr. Marieta L. C. Passos 《Chemphyschem》2015,16(9):1880-1888
Immobilization of quantum dots (QDs) onto solid supports could improve their applicability in the development of sensing platforms and solid‐phase reactors by allowing the implementation of reusable surfaces and the execution of repetitive procedures. As the reactivity of QDs relies mostly on their surface chemistry, immobilization could also limit the disruption of solution stability that could prevent stable measurements. Herein, distinct strategies to immobilize QDs onto porous aminated supports, such as physical adsorption and the establishment of chemical linking, were evaluated. This work explores the influence of QD capping and size, concentration, pH, and contact time between the support and the QDs. Maximum QD retention was obtained for physical adsorption assays. Freundlich and Langmuir isotherms were used to analyze the equilibrium data. Gibbs free energy, enthalpy, and entropy were calculated and the stability of immobilized QDs was confirmed. 相似文献
128.
129.
Dr. Tiago Rodrigues Nadine Hauser Daniel Reker Dr. Michael Reutlinger Tiffany Wunderlin Dr. Jacques Hamon Dr. Guido Koch Prof. Dr. Gisbert Schneider 《Angewandte Chemie (International ed. in English)》2015,54(5):1551-1555
We report a multi‐objective de novo design study driven by synthetic tractability and aimed at the prioritization of computer‐generated 5‐HT2B receptor ligands with accurately predicted target‐binding affinities. Relying on quantitative bioactivity models we designed and synthesized structurally novel, selective, nanomolar, and ligand‐efficient 5‐HT2B modulators with sustained cell‐based effects. Our results suggest that seamless amalgamation of computational activity prediction and molecular design with microfluidics‐assisted synthesis enables the swift generation of small molecules with the desired polypharmacology. 相似文献
130.
Castanea sativa Mill. is a species of the family Fagaceae abundant in south Europe and Asia. The fruits (chestnut) are an added value resource in producing countries. Chestnut economic value is increasing not only for nutritional qualities but also for the beneficial health effects related with its consumption. During chestnut processing, a large amount of waste material is generated namely inner shell, outer shell and leaves. Studies on chestnut by-products revealed a good profile of bioactive compounds with antioxidant, anticarcinogenic and cardioprotective properties. These agro-industrial wastes, after valorisation, can be used by other industries, such as pharmaceutical, food or cosmetics, generating more profits, reducing pollution costs and improving social, economic and environmental sustainability.
The purpose of this review is to provide knowledge about the type of chestnut by-products produced, the studies concerning its chemical composition and biological activity, and also to discuss other possible applications of these materials. 相似文献