235 research outputs found

    Cork suberin as a new source of chemicals: 2. crystallinity, thermal and rheological properties

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    Suberin samples, obtained by alkaline methanolysis from cork (Quercus suber L.), were submitted to various physical characterizations; DSC, TGA, optical microscopy, density and rheological properties. A sub stantial proportion of these oligomers possessed a microcrystalline character with a melting range between 0 and 50°C. The amorphous part was liquid at room temperature and did not display a detectable glass transition upon cooling because of its wide molecular weight distribution. The viscous behaviour of suberin at room temperature was both plastic and thixotropic because of the structuring role of the microcrystals.info:eu-repo/semantics/publishedVersio

    Electoral surveys influence on the voting processes: a cellular automata model

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    Nowadays, in societies threatened by atomization, selfishness, short-term thinking, and alienation from political life, there is a renewed debate about classical questions concerning the quality of democratic decision-making. In this work a cellular automata (CA) model for the dynamics of free elections based on the social impact theory is proposed. By using computer simulations, power law distributions for the size of electoral clusters and decision time have been obtained. The major role of broadcasted electoral surveys in guiding opinion formation and stabilizing the ``{\it status quo}'' was demonstrated. Furthermore, it was shown that in societies where these surveys are manipulated within the universally accepted statistical error bars, even a majoritary opposition could be hindered from reaching the power through the electoral path.Comment: 15 pages, 9 figure

    Reactive nitrogen/oxygen species production by nitro/nitrosyl supramolecular ruthenium porphyrin complexes

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    This manuscript reports on new nitro/nitrosyl Ru-based complexes, which were synthesized with the purpose of using them as precursors to obtain supramolecular ruthenium porphyrin species ({TPyP[Ru (NO2)(5,50-Mebipy)2]4}(PF6)4) and ({TPyP[Ru(NO)(5,50-Mebipy)2]4}(PF6)12). The photochemical and photophysical properties of these porphyrin species were investigated. Results show that the complex containing nitrite is able to produce NO by homolytic O—NO cleavage (FPPh NO = 0.05) while the {TPyP[Ru (NO)(5,50-Mebipy)2]4}(PF6)12 does it by direct labilization (FPPh NO = 0.53) of the Ru NO bond. Furthermore, a triplet quantum yield of 0.09 and 0.27 was observed for complexes containing nitrite and nitric oxide, respectively. The reactive oxygen species quantum yield for the complex {TPyP[Ru(NO) (5,50-Mebipy)2]4}(PF6)12 (0.78) is consistent with the sum of quantum yields NO release (0.53) and triplet state (0.27), which suggests that both processes participate in the formation of the reactive species. Our results show that combining these characteristics, NO production and triplet states, on the same platform could induce a synergic effect, leading to a considerable improvement in the photodynamic action of these complexes

    Cork suberin as an additive in offset lithographic printing inks

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    Suberin oligomers, isolated from cork (Quercus suber L.), were used as additives in ‘Waterless’ and vegetable-oil ink formulations, in the range of 2–10% w/w. The rheological behaviour of the suberin oligomers as well as of the inks, with and without suberin, were investigated as a function of temperature. It was shown that the addition of suberin induces a decrease of viscosity of both inks. The tack of pristine inks, suberin oligomers and their mixtures were determined at different temperatures: the variation of this parameter as a function of time provided information about the drying kinetics of these formulations. The tack of the ‘Waterless’ ink was found to increase with the introduction of suberin, whereas that of vegetable-oil based counterparts decreased. All the trends observed were interpreted in terms of the differences in composition between the two types of inks. Preliminary printing tests were carried out with the various suberin-containing inks.info:eu-repo/semantics/publishedVersio

    Multidisciplinary Experience In The Selection Of Patients For Tubal Sterilization.

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    Results of the use of a special protocol for evaluation of patients requiring tubal ligation is presented after applied by a multidisciplinary group. The authors conclude that the use of defined parameters of age, parity, marital union duration, number of children alive and the presence of maternal clinical pathology are useful to identify patients with smaller chances of regret after surgery.27% of reproductive-age women in Brazil have chosen surgical sterilization as their contraceptive method. Most of these women who have undergone tubal sterilization opted for cesarean surgery. However, given the young ages of many of these women, many regret having been sterilized. This paper summarizes the experience of a multidisciplinary group in evaluating women who apply for surgical sterilization at the Department of Tocogynecology, Faculdade de Ciencas Medicas, Universidade Estadual de Campinas in Sao Paulo. Detailed descriptions are presented of the medical and social characteristics of cases seen between June 1988 and July 1989. The authors conclude that the use of the defined parameters of age, parity, marital union duration, number of living children, and the presence of maternal clinical pathology are useful in identifying the patients who are least likely to regret undergoing surgical sterilization.113171572

    A Bibliografia do xisto

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    Descreve as características e as condições de pesquisa bibliográfica em xistos oleígenos que a Bibliografia do Xisto apresenta: cobertura exaustivada literatura internacional (12.717 referências) com indicação da(s) área(s) de conhecimento coberta(s)pelo trabalho (Aplicação, Biologia, Documentação,Economia, Geologia, História, Legislação e RegrasNormativas, Mineração e Prospecção, Mineralogia ePetrografia, Notícias, Origem, Paleontologia,Política e Programas, Propriedades Fundamentais,Química, Saúde e Tecnologia). A Bibliografia utiliza o sistema automático de indexação KWOC e é composta das seguintes partes: 1) índice Cronológico de Referências: relaciona as referências pelo ano de publicação e, dentro de cada ano, por ordem do número de registro do documento na Bibliografia do Xisto; 2) Índice de Autores:relaciona os autores em ordem alfabética, listando cronologicamente os vários trabalhos de cada um;3) índice de Termos: palavras-chave dos títulos dos documentos e áreas de conhecimento; 4) Lista da Produção Literária (total) dos Autores; 5) Lista de Ocorrência dos Termos; 6) Lista e Gráfico da Freqüência Anual dos Trabalhos; 7) Lista de Publicações Periódicas: arrola alfabeticamente as abreviaturas normalizadas dos 2.3OO títulos constantes da Bibliografia. Toda a Bibliografia do Xisto está normalizada em inglês e se encontra gravada em microfichas. Bibliografias setoriais sobre cada uma das 17 áreas de conhecimento (emais Patentes e Teses) foram produzidas a partir da grande Bibliografia, utilizando o mesmo sistema de indexação. Por solicitação dos usuários,bibliografias restritas a termos específicos ou a expressões booleanas, com entradas do Índice de Termos, podem ser produzidas, por computador, a partir da grande Bibliografia. Abstract Describes the characteristics and facilities of bibliographical research on oil shales provided by the Oil Shale Bibliography: world-wide coverage of the literature (12.717 references) classified according to 17 areas of knowledge-. Application,Biology, Chemistry, Documentation, Economy,Fundamental Properties, Geology, Health, History,Legislation and Normative Rules, Mineralogy and Petrography, Mining and Prospection, News, Origin, Paleontology, Politics and Programs, and Technology. The Bibliography uses the KWOC automatic indexing system and consists of a Chronological Index, an Author Index, a Subject Index, a List of the Authors' (total) Literary Production, a List of Occurrence of Words, a Listand Graph of the Annual Frequency of Papers and aList of Serials. The whole Oil Shale Bibliography is translated into English and is recorded in microfiches. Sectorial bibliographies on each of the 17 areas of knowledge (plus Patents and Theses)were computer produced from the Bibliography,using the same indexing system. Bibliographies restricted to specific words (keywords) or boolean expressions, may also be computer produced from the Bibliography

    Vascular Flora Of The Legado Das Águas, Reserva Votorantim, Municipalities Of Tapiraí, Miracatú And Juquiá, São Paulo, Brazil

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We present a list of vascular plants found in Legado das Águas, Reserva Votorantim, a private reserve having an area of approximately 35,000 ha that spans the municipalities of Tapiraí, Miracatú, and Juquiá, in the state of São Paulo, Brazil. The reserve is part of a complex of state-protected areas including Alto Ribeira Touristic State Park, Intervales State Park, Carlos Botelho State Park, Jurupará State Park, and Serra do Mar State Park. Together, these form an important and large area of continuous and well-preserved forest. Our study, which involved two main floristic surveys in March/April 2013 and April 2014, recorded 768 species, representing 131 families and 432 genera. The majority of species were angiosperms (619) representing 106 families and 370 genera. There were also two species of gymnosperms belonging to two genera in separate families; 147 species of ferns and lycophytes belonging to 23 families and 60 genera. In demonstrating the presence of almost 800 species of plants, of which 16 are threatened, our study highlights the importance of floristic surveys and the critical role of private protected areas in managing and preserving native flora. © 2016 Check List and Authors.1262011/22923-8, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo2015/9444-4, FAPESP, Fundação de Amparo à Pesquisa do Estado de São PauloFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Interplay between edge states and simple bulk defects in graphene nanoribbons

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    We study the interplay between the edge states and a single impurity in a zigzag graphene nanoribbon. We use tight-binding exact diagonalization techniques, as well as density functional theory calculations to obtain the eigenvalue spectrum, the eigenfunctions, as well the dependence of the local density of states (LDOS) on energy and position. We note that roughly half of the unperturbed eigenstates in the spectrum of the finite-size ribbon hybridize with the impurity state, and the corresponding eigenvalues are shifted with respect to their unperturbed values. The maximum shift and hybridization occur for a state whose energy is inverse proportional to the impurity potential; this energy is that of the impurity peak in the DOS spectrum. We find that the interference between the impurity and the edge gives rise to peculiar modifications of the LDOS of the nanoribbon, in particular to oscillations of the edge LDOS. These effects depend on the size of the system, and decay with the distance between the edge and the impurity.Comment: 10 pages, 15 figures, revtex
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