Simultaneous determination of chromium and nickel in medicinal plants by slurry sampling graphite furnace atomic absorption spectrometry

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

Genotoxic effect of phenol on the cells of onion (Allium cepa ) roots

The roots of onion (Allium cepa ) stand out for having cells with large size and small number of chromosomes. These characteristics make them useful in bioassays for the measurement of a variety of cytogenetic and morphological parameters, in which they can be used as toxicity indicators of the induction and formation of micronuclei and chromosomal aberrations. Based on this background, the potential genotoxic effect of phenol concentration on cells of A. cepa roots was investigated either in terms of induced aberrations or micronuclei formation. The results demonstrated that the higher the concentration of phenol, the higher the incidence of abnormalities, thus confirming the genotoxicity of this pollutant.

Characterization and application of nanostructured films containing Au and TiO2 nanoparticles supported in bacterial cellulose

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Combined measurement of the Higgs Boson Mass in pp collisions at root s=7 and 8 TeV with the ATLAS and CMS experiments

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The cone loading test to estimate deformability moduli of a tropical soil

The Cone Loading Test (CLT) consists of the execution of a load test on the piezocone probe in conjunction with the CPT test. The CLT yields the modulus ECLT, a parameter that can be used in the estimative of foundation settlement. It is also presented here the interpretation and the process to determine ECLT values from the stress-displacement curves obtained from cone loading tests. Several CLT tests were conducted at the experimental research site of São Paulo State University, Bauru-SP-Brazil. The geotechnical profile at the studied site is a brown to bright red slightly clayey fine sand, a tropical soil common to this region which is lateritic, unsaturated and collapsible. The results of CLT tests satisfactorily represent the behavior of the investigated soil. The penetrometric modulus ECLT for each depth was calculated considering the elastic behavior in the initial linear segment of the soil stress-strain curve. The ECLT moduli obtained for the various tests were compared to moduli obtained from PMT and DMT test results performed at same studied site. The shear modulus degradation curves obtained from the CLT tests are also presented. The comparison to PMT and DMT results indicates the CLT test is a viable complementary test to the CPT in the quest for better understanding stress-strain behavior of soils. Further, the CLT test provides a graphic visualization of the degradation of the shear modulus with increasing levels of strain. As a hybrid geotechnical test, CPT+CLT can be valuable in the investigation of non-conventional collapsible soils, whose literature lack reference parameters for the prediction of settlement in the design of foundations.

Aproveitamento do resíduo do processamento do café na composição de painéis MDP

A produção de produtos derivados de madeira e bambu vem crescendo nos últimos anos na busca de um aproveitamento mais racional dessas matériasprimas. Este trabalho tem por finalidade, o estudo da aplicação de resíduos do processamento do café em um painel MDP. Os painéis MDP foram produzidos com partículas de bambu da espécie Dendrocalamus giganteus e adição de partículas de casca de café na camada intermediária do painel, unidas por resina poliuretana à base de mamona. A caracterização físico-mecânica foi realizada baseando-se nas especificações da NBR 14810-3 (2006). Os resultados obtidos foram comparados com a norma brasileira NBR 14810-2 (2006), resultando em valores próximos aos comercialmente encontrados.

Evaluation of longitudinal modulus of elasticity in wood species for structural application

1024x768 This research aimed to investigate possible differences in values of longitudinal modulus of elasticity for wood species usually employed for structural purposes, as Castanheira (Bertholletia excelsa), Cambará (Erisma uncinatum), Cumaru (Dipteryx odorata), Jatobá (Hymenaea stilbocarpa), Garapa (Apuleia leiocarpa) and Peroba Rosa (Aspidosperma polyneuron), obtained from compression and tension parallel to grain, and static bending tests. Recommendations of the Brazilian standard ABNT NBR 7190:1997, Annex B, were followed. Statistical analysis results for the cited properties, had equivalent averages for the six wood species analyzed. This confirms that any of the three tests can be used to obtain the longitudinal elastic modulus and which could avoid the necessity of evaluating stiffness values for wood by more than one kind of mechanical test. Normal 0 21 false false false PT-BR X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

Influence of moisture content in some mechanical properties of two brazilian tropical wood species

This study aimed, with the aid of analysis of variance (ANOVA), to investigate and quantify the influence of moisture ranging between 12% and over 30% (fiber saturation) on the mechanical properties: strength and modulus of elasticity in compression and in tension parallel to grain; modulus of rupture and modulus of elasticity in static bending; shear strength parallel to grain considering wood species Ipê (Tabebuia sp) and Angelim Araroba (Vataireopsis araroba). Tests were performed according to the assumptions and calculating methods Brazilian standard ABNT NBR 7190, Anexx B, totalizing 400 tests. Results of ANOVA revealed a significant reduction (16% on average) for mechanical properties wood due to the increase in moisture content from 12% to over 30% (fiber saturation). The same behavior also occurred when assembly containing the two species was considered.

Evaluation of bamboo particleboards produced with urea-formaldheyde resin

The bamboo waste can be an alternative material to sustain the crescent demand for particleboards, also bringing ecological benefits as reduction of the pressure for raw materials and landfill space demands. In this context, this research aimed to manufacture and determine some physical and mechanical properties of particleboards with bamboo waste particles (Dendrocalamus giganteus), obtained from different sources, bonded with four different percentages of urea–formaldehyde (UF) based resin (6%, 8%, 10% and 12% related to dry material of particles). Response variables investigated were: density; moisture content; thickness swelling in 2 and 24 hours; water absorption in 2 and 24 hours; internal adhesion (STpe); strength in tension parallel to faces (STpa); modulus of elasticity (MOE) and modulus of rupture (MOR). Results permitted to conclude that particleboards as mentioned showed good performance only in the physical properties requirements imposed by Brazilian Standard NBR 14810, but this was not observed to mechanical properties considered. New researches are needed in order to optimize the producing process parameters.

Physical characterization of particleboard produced with waste from ethanol and sugar mill

The problem of proper disposal of solid waste generated in different industrial processes is one of worldwide environmental concerns nowadays. Thus, this study aimed to establish a new alternative for the disposal of two agro-industrial residues employing them to produce particleboard for different purposes in building construction. The focus was given to the reuse of the sugarcane bagasse (SB) originated during the processing of Saccharum officinarum for sugar and ethanol production, and bamboo stem leaves of Dendrocalamus giganteus(BB). For this, six particleboards were produced in the following compositions: with 100% SB, 75% SB + 25% BB, 50% SB+50% BB, 40% SB +60 BB, 25% SB+ 75% BB and 100% BB in the total mass of the composites. The particleboards physical characterization followed Brazilian Standard ABNT NBR 14810-3 to density, moisture content and water absorption. Results showed these raw materials are compatible to particleboard production.

Influence of storage period of pieces in stiffness of pinus elliottii Glulam Beams

This study aimed to investigate the influence of storage time (0, 48 hours) of Pinus elliottii pieces and the tests to obtaining modulus of elasticity (static bending and transversal vibration) in glued laminated timber beams, produced with resorcinol based adhesive and 0.8 MPa compaction pressure. After pieces were properly prepared, part of them was used in immediate three manufacturing glulam beams, tested after adhesive cure, and part stored for 48 hours under a roof with a temperature of 25°C and relative humidity of 60% for subsequent manufacturing and testing three other glulam beams. Results of analysis of variance (ANOVA) revealed that the storage period was significant influence in modulus of elasticity obtained in static bending test (8% reduction from 0 to 48 hours). This not occurred with modulus of elasticity obtained by transversal vibration test (no significant influence). ANOVA results showed equivalence of means in both test procedures. New researches ire needed to better understand the investigated phenomenon, using new wood species, other storage conditions and a great number of samples.

Task complexity reveals expertise of table tennis players

AIM: The purpose of this study was to examine the effect of intensive practice in table-­tennis on perceptual, decision-­making and motor-­systems. Groups of elite (HL=11), intermediate (LL=6) and control (CC=11) performed tasks of different levels. METHODS: All subjects underwent to reaction-­time-­test and response-­time-­test consisting of a pointing task to targets placed at distinct distances (15 and 25-­cm) on the right and left sides. The ball speed test in forehand and backhand condition just for HL and LL group. RESULTS: In CC group reaction time was higher compared to HL (P< 0.05) group. In the response-­time-­test, there was a significant main effect of distance (P< 0.0001) and the tennis-­table expertise (P= 0.011). In the ball speed test the HL were constantly faster compared to the LL in both forehand stroke (P< 0.0001) and backhand stroke (P< 0.0001). Overall, the forehand stroke was significantly faster than the backhand stroke. CONCLUSION: We can conclude that table-­tennis-­players have shorter response-­times than non-­athletes and the tasks of reaction-­time and response-­time are incapable to distinguish the performance of well-­trained table tennis players of the intermediate player, but the ball speed test seems be able to do it.

Evaluation of a plastic composite produced with residues of sugarcane bagasse and polypropylene without additives

In this research the aim was produce and evaluate a plastic composite using recycled polypropylene (PP) and fibers from sugarcane bagasse residues (SC), without the use of additives. This analysis was based on laboratorial tests for physical and mechanical characterization, according to the standards ASTM D256-00, D638-101 and D570-98 were analyzed: water absorption, thickness swelling, impact resistance, tensile strength and its correspondent deformation. For comparison it was elaborated three different compositions: 100% PP; 80% PP+20%SC; 70%PP+30%SC. The results indicate a positive correlation with the content of fiber and water absorption and thickness swelling. In the tension tests, the composites with fibers increase the value of resistance for physical efforts, bringing advantages as durability and integrity of the material, showing a viability of the composites.

Physical and mechanical characteristic of particleboards produced with residues of sugarcane and stem leaves of bamboo bonded with castor oil adhesive

In this research the aim was produce a particleboard with alternative materials and evaluated its physical and mechanical characteristics. The raw materials used are residues from sucarcane bagasse (SC) (Saccharum officinarum) and stem leaves of bamboo (B) (Dendrocalamus giganteus), bonded with a bi component adhesive based on castor oil. It was produced particleboards with five different traces: 100% SC, 75% SC+25% B, 50% SC+50% B, 25% SC +75%B and 100 % B. Their physical and mechanical characteristics were evaluated accordingly to Brazilian standard NBR 14810-3. Regarding the results obtained, it can be detached that for physical and mechanical evaluation it is evident a negative relation among the amount the sugarcane bagasse and their physical and mechanical characteristics, that is particleboards with low concentrations of sugarcane bagasse had better results. However all particleboards could be recommended for use as sealing particleboards in the segment of civil construction.