Influence of Environmental Conditioning on the Shear Behavior of Poly(phenylene sulfide)/Glass Fiber Composites

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparison of SRIM, MCNPX and GEANT simulations with experimental data for thick Al absorbers

Proton computerized tomography deals with relatively thick targets like the human head or trunk. In this case precise analytical calculation of the proton final energy is a rather complicated task, thus the Monte Carlo simulation stands out as a solution. We used the GEANT4.8.2 code to calculate the proton final energy spectra after passing a thick Al absorber and compared it with the same conditions of the experimental data. The ICRU49, Ziegler85 and Ziegler2000 models from the low energy extension pack were used. The results were also compared with the SRIM2008 and MCNPX2.4 simulations, and with solutions of the Boltzmann transport equation in the Fokker-Planck approximation. (C) 2009 Elsevier Ltd. All rights reserved.

Synthesis, characterization and thermal behaviour of solid 2-methoxybenzoates of trivalent metals

Solid-state Ln(L)(3) compounds, where Ln stands for trivalent Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y and L is 2-methoxybenzoate have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results provided information on the composition, dehydration, coordination mode, structure, thermal behaviour and thermal decomposition.

Synthesis, characterization and thermal behaviour of light trivalent lanthanides folates on solid state

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

Synthesis, characterization and thermal behaviour of solid-state 3-methoxybenzoates of heavy trivalent lanthanides and yttrium(III)

Solid-state Ln(L)(3) compounds, where Ln stands for trivalent Tb, Dy, Ho, Er, Tm, Yb, Lu and Y, and L is 3-methoxybenzoate, have been synthesized. X-ray powder diffractometry, infrared spectroscopy, complexometry and elemental analysis were used to characterize the compounds. In order to study the thermal behaviour of these compounds simultaneous thermogravimetry and differential thermal analysis (TG-DTA) and differential scanning calorimetry (DSC) were used. The results provided information on the composition, dehydration, polymorphic transformation, thermal stability and thermal decomposition of the synthesized compounds.

Synthesis, characterization and thermal behavior on solid tartrates of light trivalent lanthanides

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

Synthesis, characterization and thermal behaviour of solid-state tartrates of heavy trivalent lanthanides and yttrium(III)

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

2-methoxybenzylidenepyruvate with heavier trivalent lanthanides and yttrium(III) - Synthesis and characterization

Solid-state Ln(2-MeO-BP) compounds, where Ln stands for trivalent Eu to Lu and Y(III) and 2-MeO-BP (which is 2-methoxybenzylidenepyruvate) have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffraction, infrared spectroscopy and other methods of analysis were used to characterize and to study these compounds. on the base of the obtained results an Ln(2MeO-BP)(3)center dot H2O general formula can be established.

Synthesis, Characterization and Thermal Behaviour of Solid 2-Methoxycinnamylidenepyruvate of Light Trivalent Lanthanides

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

Synthesis, characterization and thermal behaviour of heavy lanthanide and yttrium pyruvates in the solid state

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

Zymomonas mobilis: um microrganismo promissor para a fermentação alcoólica

In many countries, fermentation studies regarding the use of bacteria instead of yeasts to reduce the period of alcoholic fermentation have been carried out. In Brazil, all the industrial alcohol production is carried out by yeasts as fermentation microorganisms and little is known about other microorganisms with potential to produce alcohol industrially. Brazil stands out in the energy sector worldwide and thus some institutions have been selecting microorganisms which are more efficient in the alcohol production process. Alcoholic bacteria from species Zymomonas mobilis present technological characteristics with potential to be used for alcoholic fermentation at industrial scale, since it exhibits promising abilities to transform sugars into alcohol and carbon dioxide, at conditions similar to the ones required by yeasts. Zymomonas mobilis is a unique bacteria among the microbial world, with peculiar growth, energy production and response to culture conditions, causing a great interest in scientific, biotechnological and industrial fields. The bacteria's ability to make possible energy production in favor of product formation, respond to physical and chemical environmental manipulation as well as its limited product formation make it an ideal microorganism for the study and development of microbial processes for ethanol production.

Efeito alelopático de extrato aquoso de folhas de Azadirachta indica A. Juss. em alface, soja, milho, feijão e picão-preto

The family Meliaceae has been identified as one of the most promising for biological control, as most species have biologically active compounds. Among the species, the Neem (Azadirachta indica A. Juss) is that stands out most for its efficiency and low toxicity, and it is utilized to control insects, fungi and nematodes. The aim of this work was to verify the allelopathic potential of aqueous extract of fresh leaves of Neem on germination of lettuce, soybeans, maize, beans and Bidens pilosa, as a way to control this weed. The extract was obtained by grinding 200g/L of fresh leaves of the Neem (considered extract 100%) and diluting in distilled water at concentrations of 80, 60, 40, and 20%, and a control with only water. The seeds were kept in the germination chamber at a temperature of 25 degrees C, with photoperiod of 12 hours of light. The aqueous extract affected the germination percentage and average length root of lettuce, with values of 1% and 0.1, cm respectively. For the soybeans, the extract influenced negatively the average time of germination and average speed of germination. There was a drastic reduction of the average root length at higher concentration for soybean, corn and beans. For Bidens pilosa all the parameters analyzed were negatively affected, which means sensitivity to the extract. The bioassay performed in the laboratory showed that the aqueous extract of fresh leaves of Azadirachta indica has allelopathic effect on all species.

Os efeitos da ação antrópica sobre a distribuição de macroinvertebrados no Rio Guareí, São Paulo

In this study, it was examined, during the period from March to December 2006, the effects of human disturbance on themacroinvertebrates that live near macrophytes in Guare River, São Paulo State - Brazil. It was questioned if the high conductivityrecorded in Guare River affected the distribution of the macroinvertebrates and what were the most important variables thataffect macroinvertebrates in a river with a strong nutrient concentration. The objective of this study was to investigate theeffects of environmental variables on densities and composition of the macroinvertebrates. Three stands of aquatic plantswere sampled with with 0.25 mm mesh net on a 0.07 m2 square metal frame. Air and water temperature, depth, pH, electricalconductivity, suspended solids, dissolved oxygen and macrophyte biomass were measured. A canonical correspondence analysis(CCA) was performed using the density of the macroinvertebrates and environmental variables. Chironomidae, Culicidae,Acanthagrion, Coryphaeschna, Erythrodiplax, Miathyria marcella, Micrathyria, Gastropoda, Ostracoda and Hemiptera werethe only taxa that showed significant correlation with the axes. From the results, we can conclude that the high conductivity recordedin Guare River due to the high amount of organic matter released during its course did not significantly affected thedistribution of the macroinvertebrates during the studied period. However, the ACC recorded that oxygen was the most significantenvironmental factor for the density variance of the macroinvertebrates, especially larval Odonata.

Positron-helium scattering: Resonance and differential cross sections

We study positron-helium scattering using close coupling approximation (CCA) employing different combinations of the following basis functions: He(1s1s), He(1s2s), He(1s2p), Ps(1s). and Ps(2s), where Ps stands for the positronium atom. We observe a prominent S wave resonance of width 2 eV at about 30 eV, in excitation and rearrangement cross sections to He(1s2s), He(1s2p), Ps(1s) and Ps(2s) states. We also report results of differential cross sections for the excitation of helium and positronium formation.

Variação da massa específica da madeira de Eucalyptus grandis aos 8 anos de idade em função de diferentes níveis de produtividade

It were analyzed Eucalyptus grandis trees of 8 years old in the forest group of Duraflora S/A, with different annual increments based on volume, to the related studies of specific gravity values based on productivity indexes. The methodology used in analysis of specific gravity was the gamma-ray attenuation technique of Americium-241. The Eucalyptus grandis showed a specific gravity decreasing with the increasing of parcel productivity. For a gain of 3,5 m3 in productivity there was a decreasing of 1% in specific gravity. Nevertheless, it was not observed correlation between specific gravity and basal area in a same parcel. The present work stands out too, some of the difficulties found with relation to wood specific gravity determinations and emphasize the importance of take samples in the form of full rounded plates in three or four relative positions in the tree.