Influence of Ca concentration on the electric, morphological, and structural properties of (Pb,Ca)TiO3 thin films

Pb1-xCaxTiO3 (0.10less than or equal toxless than or equal to0.40) thin films on Pt/Ti/SiO2/Si(100) substrates were prepared by the soft solution process and their characteristics were investigated as a function of the calcium content (x). The structural modifications in the films were studied using x-ray diffraction and micro-Raman scattering techniques. Lattice parameters calculated from x-ray data indicate a decrease in lattice tetragonality with the increasing content of calcium in these films. Raman spectra exhibited characteristic features of pure PbTiO3 thin films. Variations in the phonon mode wave numbers, especially those of lower wave numbers, of Pb1-xCaxTiO3 thin films as a function of the composition corroborate the decrease in tetragonality caused by the calcium doping. As the Ca content (x) increases from 0.10 to 0.40, the dielectric constant at room temperature abnormally increased at 1 kHz from 148 to 430. Also calcium substitution decreased the remanent polarization and coercive field from 28.0 to 5.3 muC/cm(2) and 124 to 58 kV/cm, respectively. These properties can be explained in terms of variations of phase transition (ferroelectric-paraelectric), resulting from the substitution the lead site of PbTiO(3)for the nonvolatile calcium. (C) 2002 American Institute of Physics.

Intelligent alarm processing

This paper presents the analysis that have been carried out in the alarm system of the DCRanger EMS. The intention of this study is to present the problem of alarm processing in electric energy control centers, its various aspects and operational difficulties due to operator needs. Some tests are produced in order to identify the desirable features an alarm system should possess in order to be of effective help in the operative duty. © 2006 IEEE.

Fostering economic policy coordination in Latin America: the REDIMA approach to escaping the prisoner's dilemma

Includes bibliography

Comparison of impurity profiles of lipiblock® vs. orlistat using HPLC and LC-MS/MS

Comparative HPLC-UV and LC-MS/MS studies of impurity profiles of a reference sample (Xenical®, F. Hoffmann-La Roche Ltd., Switzerland) vs. generic (Lipiblock®, EMS-Sigma Pharma, a generic drug) were carried out with ethanol extracts of commercial samples. The generic formulation contained higher levels of common impurities as well as a considerable number of impurities not found in the reference product. The detected impurity profile of Lipiblock® revealed that it most likely is based on fermentation. Since the effect of the impurities is unknown, at this point fully synthetic Xenical® appears to offer a better safety margin than Lipiblock® which, however, compares quite well to other generic formulations.

Cost-effective composite electrode for the fast voltammetric screening and determination of riboflavin (B2) and pyridoxine (B6) in pharmaceuticals

Different solid composites made by mechanical dispersions of graphite particles into heated paraffin (from 65 to 80% graphite, in mass) were prepared and assessed in order to optimize their use in electrochemical and electroanalytical procedures for bioanalysis. Besides these, composites were also evaluated by thermoanalytical techniques aiming to study their conservation and long-term stability (over eight months without special care), among others. Best results were found at 80% m/m graphite in paraffin. Such electrode combines low-cost, stability, sensitivity, ease of maintenance and clearance, besides the possibilities of manufacture in many different forms and shapes (with or without modifications) and applicability in a wide range of pH. Electrochemical studies by different voltammetric techniques involving vitamins from complex B (riboflavin and pyridoxine) leaded to a better understanding about their electrooxidative processes onto carbon-composite electrodes, specially regarding reversibility and pH-dependence. Data were also acquired and optimized with analytical purposes, being square-wave voltammetry in pH 4.2 chosen by its many advantages. Good linearity between peak responses as function of concentration were reached from 5 to 43 μmol L-1 for riboflavin (peak at -0.257 V) and up to 8.5 × 10-4 mol L -1 for pyridoxine (peak at +1.04 V), best studied conditions; limits of detection (at an S/N of 3) for both analites showed to be circa 1.0 mol L-1. Different commercial samples were analyzed for riboflavin (EMS® complex B syrup) and pyridoxine (Citoneurin 5000 Merck® ampoules) providing 96.6% and 98.7% recoveries, respectively.

Guidelines for the integration of certifiable management systems in industrial companies

Organizations often operate in turbulent environments characterized by intense competitiveness, constant technological progress, new market requirements, and scarce natural resources. This scenario imposes the constant need for change in the operation and companies' management. The integration of certifiable management systems is an effective alternative in this sense. The objective of the present study is to propose guidelines for the integration of the ISO 9001 Quality Management System (QMS), ISO 14001 Environmental Management System (EMS) and OHSAS 18001 Occupational Health and Safety Management System (OHSMS) in industrial companies. These guidelines were developed based on a theoretical framework and on the results from fourteen case studies performed in Brazilian industrial companies. The proposed guidelines were divided into three phases: A) integration planning, b) integration development, and c) integration control and improvement.

Avaliação in vitro da citotoxicidade e genotoxicidade de diferentes cimentos endodônticos em fibroblastos V79

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo in vitro de apicectomia e retropreparos realizados por diferentes métodos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Um estudo sobre a relação do sistema de gestão ambiental ISO 14001 com a adoção de procedimentos de produção mais limpa em empresas industriais brasileiras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O PT na prefeitura municipal de São Paulo (1989-1992): da concepção de educação à formulação de uma política educacional

Pós-graduação em Educação - FFC

Efeito das terras raras nas propriedades óticas do BaM'O.IND.3'(M==Zr, Ti)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação dos efeitos do brometo de etídio em Drosophila melanogaster (Diptera-Drosophilidae)

Pós-graduação em Biologia Animal - IBILCE

Análise da utilização de cartas geotécnicas em diferentes escalas para a gestão ambiental de rodovia em operação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

O município e a organização da educação: caminhos e desafios da criação e implantação do sistema municipal de ensino de Ananindeua-PA

A pesquisa investigou o processo de institucionalização do Sistema Municipal de Ensino de Ananindeua - Pará, considerando a democratização, descentralização da educação e autonomia municipal como categorias centrais. Objetivou a análise de sua organização desde a criação da Lei do Sistema Municipal de Ensino, por meio dos documentos oficiais que lhe dão suporte, sua caracterização enquanto sistema municipal e a formulação da sua política educacional. A metodologia utilizada foi uma pesquisa bibliográfica e análise documental. Os resultados mostram que a construção dos sistemas municipais de ensino no Brasil vem se dando pela recuperação do pacto federativo, redefinindo-se as responsabilidades dos entes federados, num contexto de grandes mudanças no cenário educacional; o município brasileiro assumiu um papel fundamental nesta organização, passando a ter a prerrogativa legal de constituir seu próprio sistema de ensino; a relação entre descentralização e democratização das tomadas de decisões não é direta, sendo defendida como uma oportunidade de se dar um novo significado às formas de gestão das instâncias públicas; a transferência da administração de escolas estaduais para o nível local se mostrou como um grande viés da descentralização; o município de Ananindeua ainda busca a consolidação do seu sistema de ensino e, no âmbito de sua função normativa e de mobilização, busca a participação dos diversos segmentos sociedade local. Conclui-se que para a criação do SME de Ananindeua se fez uma opção política que exigiu daqueles que são responsáveis pela educação municipal assumirem responsabilidades por sua organização; sua construção ensejou a análise dos problemas locais da educação, a definição de estruturas e funções dos organismos locais e percepção dos fins e valores da educação local.

Qualificação de produtores rurais em boas práticas agrícolas visando adesão a sistemas de certificação socioambiental

Pós-graduação em Ciência Florestal - FCA