Some Physical and Mechanical Properties of Medium-Density Fiberboard Made from Giant Bamboo

The objective of this study was to evaluate the density, density profile, water swelling and absorption, modulus of elasticity and rupture from static bending, and tensile strength of experimental medium-density fiberboards manufactured using Dendrocalamus giganteus (Munro bamboo). The fiber production was carried out through the chemo-thermo-mechanical pulping process with four different conditions. The panels were made with 10% urea formaldehyde resin based on dry weight of the fibers, 2.5% of a catalyzer (ammonium sulfate) and 2% paraffin. The results indicate that treatments with the highest alkali (NaOH) percentage, time and splinter heating temperature improved the physical properties of the panels. The root-fiber interface was evaluated through scanning electron microscopy in fracture zones, which revealed fibers with thick, inflexible walls. The panels' mechanical properties were affected due to the fiber wall characteristics and interaction with resin. Giant bamboo fiber has potential for MDF production, but other studies should be carried out.

A Quality Assessment of Titanium Castings Produced in an Experimental Short-Heating-Cycle Investment

The aim of this study was to evaluate the quality of casting produced in an experimental short-term heating-cycle investment. Thus, reaction layer and castability of titanium casting using an experimental spinel-based investment (VR) with short heating cycle were compared with the commercial short-heating-cycle spinel-based investment Trinell (TR), the silica-phosphate-based investment Rematitan Plus ( RP), and the conventional spinel-based investment Rematitan Ultra (RU). VR has polymeric fibers added to inorganic particles. Reaction layer assessments were carried out using Vickers hardness and elemental analysis using dispersive X-ray microanalysis (EDX). Mesh patterns were used for castability test, and powder characterization was made by scanning electron microscopy (SEM). Hardness evaluation showed no difference among the investments between 100 and 200 mu m. The most important contaminant element for VR, TR, and RU was oxygen. Higher levels of mold filling were found for TR, VR, and RU compared with that obtained with RP. The quality of castings, characterized by means of the assessments of reaction layer and castability, made from the VR was similar to the commercial investments TR and RU but superior to the RP.

Cartilage Reconstruction Using Self-anchoring Implant with Functional Gradient

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Analysis of the Stresses in Corrugated Sheets under Bending

This paper presents three different numerical models for the evaluation of the stresses in corrugated sheets under bending. Regarding the numerical simulations different approaches can be considered, i.e., a elastic linear analysis or a physical nonlinear analysis, that considers criteria to fail for the sheet material. Moreover, the construction of the finite element mesh can be used shell elements or solid elements. The choice of each finite element must be made from the consideration of their representativity before behavior to be simulated. Thus, the numerical modelling in this manuscript was performed from the three-dimensional models using the SAP2000Nonlinear software, version 7.42, which has as base the finite elements method (FEM). It was considered shell elements in the build the mesh of finite elements and an analysis of type elastic linear in this case. Five mm thick sheets were evaluated considering three different longitudinal dimensions (spans), i.e., 1100 mm, 1530 mm and 1830 mm. The applied load to the models was 2500 N/m and it was verified that the spans of support of sheets have a significant influence on the results of stresses. The sheets with larger spans present larger stresses for the same applied load. The most intense values of tension occur in the troughs (low waves) of the sheets, on the lower surface, while the most intense values of compression occur in the crests (high waves), on the upper surface of the sheet. The flanks, which are the parts among the troughs and crests of the sheets, are submitted to low levels of stresses. The numeric results of the stresses showed a good agreement with the results obtained from other researchers(3) and these results can be used to predict the behavior of corrugated sheets under bending.

Photo-Induced Conductivity of Heterojunction GaAs/Rare-Earth Doped SnO2

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Effects of Weathering Exposure on the Physical, Mechanical, and Thermal Properties of High-density Polyethylene and Poly (Vinyl Chloride)

This paper presents results describing the physical, mechanical, and thermal properties (melt flow index - MFI and oxidative induction time - OIT) of high density polyethylene and poly (vinyl chloride) after weathering exposure (6, 12, 18, and 30 months). The materials exposed were geomembranes of two thicknesses: 1.0 and 2.0 mm (PVC) and 0.8 and 2.5 mm (HDPE). The climate parameters (average) obtained were 25 degrees C (temperature), 93 mm (precipitation), 66% (relative humidity), and 19 MJ/m(2). day (intensity of global radiation). Some results showed, for instance, that the behavior of the geomembranes changed after the exposures. A few minor variations in physical properties occurred. The density and thickness, for instance, varied 0.5-1.0% (average) for both the PVC and HDPE geomembranes. The mechanical properties changed as a function of the period of exposure. In general, some decreases were verified by the deformation of PVC. The samples became more rigid. In contrast, HDPE geomembranes became more ductile. Despite the variations in elasticity, some increases in deformability were verified. An MFI test showed some degradation in HDPE geomembranes. OIT tests revealed small values for both intact and exposed samples.

Utilization of Minimum Quantity Lubrication (MQL) with Water in CBN Grinding of Steel

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

Viscoelastic Behavior of Multiwalled Carbon Nanotubes into Phenolic Resin

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

Nanostructured Composites Based on Carbon Nanotubes and Epoxy Resin for Use as Radar Absorbing Materials

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of Decomposition Kinetics of Poly (Ether-Ether-Ketone) by Thermogravimetric Analysis

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

Second Phase Precipitation in Ultrafine-grained Ferrite Steel

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

Escrita e Síndrome de Down

The project, developed at the Health and Education Studies´ Center, in the Unity of the Science and Philosophy’s College, UNESP, Marilia´s campus, had as goal the development of a study about the appropriation of writing by children with Down ’s syndrome. Five children, from 10 to 13 years old, on different situations of scholar levels, were took part in the project. As research procedure, it was developed weekly pedagogical interventions, based on HistoricalCultural Theory. At the beginning, the group presented different dimensions of approximation with the writing universe. It was observed advances on the graphic representation and on the individual trials of writing. Two childrens began to build small texts, one of the children is on the beginning of the alphabetic writing and two other children continue to present difficulties, getting close of the writing in a very not confortable way, stuck on the scholar formality and a direct mediation to the words constitution is needed.

A formação do leitor do ensino fundamental: as legendas cinematográficas

Given the pedagogical practices in respect of acts of reading in the current context of education institutions in primary education, it is clear that they are connected to decipher and not the search for meaning and understanding. In thinking about the use of new technologies that can contribute to the formation of the reader, it is believed that reading subtitles allows such training since it requires a quick read that does not cling to every word and attribution of meaning to monitor all the course of the film. This makes the children learn to read and make sense using the expertise of its cultural heritage. This research aimed to analyze the contribution of film subtitles to the formation of the reader from elementary school. Thus, students were invited, between the ages of six and ten years, with interest to see subtitled films, and they learn to read subtitles. The film sessions were held fortnightly at the school, in an adapted room. After the sessions, held group discussions to see what the problems in understanding the plot this paper presents data on the session of the film "Coração de Tinta". Children, assisted by the researchers could understand the story and learned to articulate their knowledge in situations of movies. The research is ongoing, but we can see that during the projection there are indications that they are able to read the subtitles, sometimes lose the timing of reading, but gradually evolve in the field of reading this kind of discourse.

Exploração sexual de menores e o papel da instituição escolar

Prostitution is an activity that generates constant conflict and controversy. The way it is practiced leads, in some specific situations, the legal framework. For the analysis of the role of school and sex education, this research aimed to: identify and analyze the views of managers and teachers living with sexual exploitation of children in two schools in the state schools of a city of the State of São Paulo and to determine whether the subject is part of school curricula in the schools surveyed and discussed how teachers. The research is part of qualitative research in education and had the strategy of data collection a questionnaire with managers and teachers of educational institutions surveyed. The data collected and analyzed showed that the school, being a place that works with multiculturalism is that, as a place where the "Sex Education" should be worked out, mainly to educate their students not to enter the world of sexual exploitation. Therefore, the school is the place for fundamental change in mentality of children and adolescents who are forced to surrender to sexual exploitation.

Produção científica de bolsistas pesquisa em Ciência da Informação do Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) - um estudo com artigos de periódicos

Information Science (IS) research has strongly grown in Brazil, in the last decade, and, as a consequence, it was possible to observe a growth of the support given by the Brazilian National Scientific and Technological Development Council - CNPq. In this sense, this paper aims to analyze the scientific production (journal papers) of the 15 IS researchers who have the highest level research fellowships during the period between 2001 and 2010. Data were analyzed in terms of bibliographic dispersion, internationalization, and scientific collaboration as well as in terms of the most prominent journals. The results (219 papers) evidence an average of around 1.5 papers per author per year and a group of 63 different journals (60% evaluated under levels Qualis A1 and B1). The journal DataGramaZero is strongly present since it responds for 22% of the whole production. It was possible to observe a still shy presence of foreign journals and none of them belong to the Anglo-Saxon environment. The kind of authorship is well-balanced between individual and collective ones, including inter-institutional collaboration. It is possible to conclude that this group is mature and very productive, and it represents an academical IS leadership in Brazil but still lacks more international visibility.