Filmes finos ferroelétricos do tipo PBCT, PBST e PCST: estudo experimental e teórico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Synthesis and photocatalytic properties of bismuth titanate with different structures via oxidant peroxo method (OPM)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Sodium titanate as basic catalyst in transesterification reactions

Sodium titanate was synthesized by the sol-gel method and characterized using X-ray diffraction, thermogravimetry-mass spectrometry, atomic absorption spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis and nitrogen physisorption. The non-calcined material was active as a catalyst in transesterification reactions and showed high stability. An appreciable loss of activity on the fourth reuse was accompanied by the appearance of a new species of oxygen and segregated sodium, identified by X-ray photoelectron spectroscopy (XPS). The XPS spectrum showed that the basic nature of the framework oxygen was inferior to the original basicity, which explained the decline in catalytic activity. (C) 2013 Elsevier Ltd. All rights reserved.

Europium-doped calcium titanate: Optical and structural evaluations

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Simple, Direct and Simultaneous Stripping Voltammetric Determination of Lead and Copper in Gasoline Using an In Situ Mercury Film Electrode

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Assessing the replacement of lead in solders: effects on resource use and human health

Human health and environmental concerns are not usually considered at the same time. Tin-lead solders are still widely used in several countries, including Brazil, by manufacturers of electronic assemblies. One of the options to reduce or eliminate lead from the manufacturing environment is its replacement with lead-free alloys. This paper applies emergy synthesis and the DALY indicator (Disability Adjusted Life Years) to assess the impact of manufacturing soft solder using tin, lead and other metals on the environment and on human health. The results are presented together with the company's financial results and the results calculated from the Brazilian statistical value of life. The calculation of emergy per unit showed that more resources are used to produce one ton of lead-free solders than to produce one ton of tin-lead solders, with and without the use of consumer waste recovered through a reverse logistics system. The assessment of air emissions during solder production shows that the benefits of the lead-free solution are limited to the stages of manufacturing and assembling. The tin-lead solder appears as the best option in terms of resource use efficiency and with respect to emissions into the atmosphere when the mining stage is included. A discussion on the influence of the system's boundaries on the decision-making process for materials substitution is presented. (C) 2012 Elsevier Ltd. All rights reserved.

Chromium, Cadmium, Nickel, and Lead in a Tropical Soil after 3 Years of Consecutive Applications of Composted Tannery Sludge

Agricultural use of tannery sludge (TS) may increase risks to soils. Thus, composting is recognized as one of the most suitable alternatives for TS recycling. Field experiments were carried out to evaluate the effects of composted tannery sludge (CTS) on chromium (Cr), cadmium (Cd), nickel (Ni), and lead (Pb) accumulation in soil after 3 years. Soil samples were collected 60 days after CTS application. After 3 years, The CTS increased Cr and Ni content, while Cd and Pb contents decreased. The third year, Cr contents showed linear increases as CTS rates were applied. The application of CTS, after 3 years, in the 2.5, 5, and 10 Mg ha(-1) increased Cr significantly (140.7%, 159.7%, and 19%, respectively) and Ni (32%, 53%, and 43.8%, respectively) contents in the soil surface layer. This means that consecutive amendments of CTS increase Cr contents in the soil and plants.

Bismuth as a general internal standard for lead in atomic absorption spectrometry

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structural, microstructural, optical and electrical properties of (Pb,Ba,Sr)TiO3 films growth on conductive LaNiO3-coated LaAO(3)(100) and Pt/Ti/SiO2/Si substrates

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Combination Therapy for the Cardiovascular Effects of Perinatal Lead Exposure in Young and Adult Rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Titanate nanotubes produced from microwave-assisted hydrothermal synthesis: Photocatalytic and structural properties

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Structural disorder-dependent upconversion in Er3+/Yb3+-doped calcium titanate

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Lead-free BaBi4Ti4O15 ceramics: Effect of synthesis methods on phase formation and electrical properties

The processing of ferroelectric BaBi4Ti4O15 (BBT) ceramics from powders prepared by conventional solid state reaction (SSR) and mechanochemical activation (MA) has been investigated. It was shown that MA synthesis reduces the synthesis temperature of BBT powders, leading to smaller particles with reduced anisotropy and consequently to smaller grain size of ceramics. Dielectric properties were investigated in a wide range of temperatures (20-800 degrees C) and frequencies (1.21 kHz to 1 MHz). The relative dielectric permittivity at Curie temperature was higher for solid state obtained ceramics than for the mechanically treated ones. The conductivity of sintered samples was studied, suggesting decreasing of conductivity of BBT-MA in comparison with BBT-SS ceramics. The influence of the grain and the grain boundaries contribution to the dielectric behavior in both ceramics was analyzed through impedance spectroscopy. A well-defined ferroelectric hysteresis loop was obtained for both samples. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Melhoria do processo de reparo por meio da redução de Lead Time em uma empresa de som automotivo

The constant search for improvement and survival of the companies makes essential the utilization of cost reduction strategies and resources optimization. This study had as its objective the utilization of Lean Manufacturing tools for the repair process lead time reduction, in a car audio manufacturer. Performing an action research, the major problems were studied, such as the potential causes and the possible improvement activities, using the DMAIC methodology. An action plan was developed for all involved processes and, as a result, the objective was reached by making a direct impact on the customers’ satisfaction and adding a competitive differential for the company

Projeto de mapeamento do lead time de uma empresa multinacional do ramo sucroalcooleira: estudo de caso

Facing the competitive current market, increases the growing managerial commitment to minimize the frequent occurrence of service failures that characterized the past. Given the fact that the supply of a product in the correct location and on time, undamaged and correctly billed market requirement becomes framed the present work. Based on a case study, supported in parallel bibliographical references in the literature in a company of sugar and alcohol sector, the survey aims to measure and evaluate the real-time delivery from suppliers in order to ensure the best level of service to the company in question by suppliers, by reducing idle time of delivery, since the control system does not supply the pre-established and / or observed above, thus obtaining a better management and supply of replacement material. To assist the work, developed a project in the company in question in order to analyze and identify applications of concepts of lead time along the supply chain through an exploratory study in order to provide a beneficial outcome to the company through monitoring and performance of its suppliers, which will enable an aid to future decision-making