Thin films generated by plasma immersion ion implantation and deposition of hexamethyldisilazane mixed with nitrogen in different proportions

In this work, it was used a plasma system composed of a cylindrical stainless steel reactor, a radio-frequency (13.56MHz) power source fixed at either 25 W or 70 W, a power source with a negative bias of 10kV and a 100Hz pulse. The system worked at an operational pressure of 80mTorr which consisted of varying concentrations of the monomer HMDSN and gaseous nitrogen in ratios: HMDSN (mTorr)/nitrogen (mTorr) from 70/10 to 20/60 in terms of operational pressure. The structural characterization of the films was done by FTIR spectroscopy. Absorptions were observed between 3500 cm(-1) to 3200 cm(-1), 3000 cm(-1) to 2900 cm(-1), 2500 cm(-1) to 2000 cm(-1), 1500 cm(-1) to 700 cm(-1), corresponding, respectively, to OH radicals, C-H stretching bonds in CH2 and CH3 molecules, C-N bonds, and finally, strain C-H bonds, Si-CH3 and Si-N groups, for both the 70 W and the 25 W. The contact angle for water was approximately 100 degrees and the surface energy is near 25mJ/m(2) which represents a hydrophobic surface, measured by goniometric method. The aging of the film was also analyzed by measuring the contact angle over a period of time. The stabilization was observed after 4 weeks. The refractive index of these materials presents values from 1.73 to 1.65 measured by ultraviolet-visible technique.

Structural characteristics of silica sonogels prepared with different proportions of TEOS and TMOS

Sonohydrolysis of mixtures of tetraethoxysilane (TEOS) and tetramethoxysilane (TMOS) with different TMOS/(TMOS + TEOS) molar ratio R was carried out to obtain similar to 2.0 x 10(-3) mol SiO2/cm(3) and similar to 86%-volume liquid phase wet gels. Aerogels were obtained by supercritical CO2 extraction in autoclave. The samples were analyzed by small-angle X-ray scattering (SAXS) and nitrogen adsorption. The structure of the wet gels can be described as a mass fractal structure with fractal dimension D similar to 2.2 and characteristic length increasing from similar to 4.6 nm for pure TEOS to similar to 6.4 nm for pure TMOS. A fraction of the porosity is eliminated with the supercritical process. The fundamental role of the TMOS/(TMOS + TEOS) molar ratio on the structure of the aerogels is to increase the porosity and the pore mean size as R changes from pure TEOS to pure TMOS. The supercritical process increases the mass fractal dimension and shortens the fractality domain in the mesopore region. A secondary structure appearing in the micropore region of the aerogels can be described as a mass/surface fractal structure with correlated mass fractal dimension D-m similar to 2.6 and surface fractal dimension D-s similar to 2.3. (C) 2007 Elsevier B.V. All rights reserved.

Processing and properties of Ag/BSCCO PIT tapes containing different proportions of silver metal powder

Monofilamentary tapes (150 pm thickness) were prepared by swaging and rolling silver tubes containing the Bi:2212 ceramic (granulation below 20 mum) and the silver powder (about 0.8 mum). The study has been made, among other samples, on tapes with nominal proportions of 0, 10 and 20 wt.% of silver. The samples were characterized by SEM, and by electrical measurements under varying applied magnetic field. The measurements of J(c) showed that the addition of 10 wt.% silver powder is very beneficent to this property, doubling the obtained values at 60 K, while the 20 wt.% tape presented very low J(c). The tape with no silver content showed to have a J(c) as high as 2.2 x 10(5) A/cm(2), at 4.2 K, zero applied magnetic field. (C) 2004 Elsevier B.V. All rights reserved.

Potentials of biogas production from young bulls manure fed with different diets

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resíduos e subprodutos agroindustriais e grãos como substratos para produção do fungo entomapatogênico Lecanicillium lecanii

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Histopathological and histomicrobiological study of root canal therapy medication, comparison of calcium hydroxide versus gutta-percha with zinc oxide/eugenol in the teeth of dogs

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

Avaliação de tecnologias de refúgio no cultivo de milho transgênico

O objetivo deste trabalho foi comparar o uso de refúgio tradicional em áreas separadas com a tecnologia alternativa de refúgio pela mistura de sementes não transgênicas no saco (refuge in the bag - RIB) em diferentes proporções. Foram utilizados os híbridos comerciais transgênicos AG 7000YG e DKB 390YG com refúgios plantados com as respectivas cultivares convencionais. Avaliaram-se sete tratamentos: RIB com quatro proporções de mistura de sementes não transgênicas (2,5, 5,0, 7,5 e 10%) no saco; refúgio tradicional, com 10% da área plantada exclusivamente com cultivar não transgênica; e área totalmente cultivada com plantas transgênicas ou totalmente com plantas não transgênicas. O híbrido DKB 390YG foi o mais produtivo. Para este híbrido, não foram observadas diferenças de produtividade entre os tratamentos, com exceção do controle inteiramente convencional, que produziu menos. Com o híbrido AG 7000YG, a tecnologia RIB com proporções de 5,0 e 7,5% de sementes não transgênicas apresentou as maiores produtividades, significativamente superiores às do refúgio tradicional, que não diferiu do controle convencional. Nos tratamentos RIB, as diferenças nas intensidades de dano por Spodoptera frugiperda não se refletiram em diferenças na produtividade. O refúgio no saco é alternativa viável para substituir o método de refúgio utilizado atualmente.

Sexagem de espermatozoides bovinos por centrifugação em gradiente descontínuo de densidade de Percoll

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

Nutrição e produção da bananeira 'Prata-anã' adubada com zinco e boro diretamente no rizoma, via muda desbastada

Com o objetivo de avaliar o efeito de diferentes doses de Zn e B, aplicados diretamente no rizoma, via muda desbastada, sobre a nutrição das plantas e produção da bananeira 'Prata-anã', foi instalado um experimento em Jaíba - MG, sob irrigação, conduzido por três ciclos produtivos consecutivos. Utilizou-se o desbastador lurdinha para extrair a gema apical de um broto cortado rente ao solo, de forma que, no local, ficasse um orifício onde os adubos foram aplicados. Empregou-se o delineamento experimental inteiramente casualizado, com 20 tratamentos resultantes de um fatorial completo entre 5 doses de zinco (0; 2,5; 5,0; 7,5 e 10,0 g de Zn família-1 ano-1) x 4 doses de boro (0; 0,68; 1,36 e 2,04 g B família-1 ano-1), com 10 repetições de uma planta. Avaliaram-se os teores de nutrientes na terceira folha e a produção em massa de frutos por cacho. Os adubos promoveram alterações nos teores foliares de nutrientes, porém sem magnitude suficiente para alterar a condição nutricional quando se consideram as faixas de suficiência. O Zn interferiu na produção, porém os menores valores foram observados na dose intermediária e não houve ajuste de modelo de regressão.

Nota científica: teste de aceitação de bebida mista de soja e amora

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

Biodiesel CO2 emissions: A comparison with the main fuels in the Brazilian market

The use of biodiesel is increasing as an attractive fuel due to the depleting fossil fuel resources and environmental degradation. This paper presents results of an investigation on the potentials of biodiesel as an alternative fuel and main substitute of diesel oil, comparing the CO2 emissions of the main fuels in the Brazilian market with those of biodiesel, in pure form or blended in different proportions with diesel oil (2%, 5%, and 20%, called B2, B5, and B20, respectively). The results of the study are shown in ton CO2 per m(3) and ton CO2 per year of fuel. The fuels were analyzed considering their chemical composition, stoichiometric combustion parameters and mean consumption for a single vehicle. The fuels studied were: gasoline, diesel oil, anhydrous ethyl alcohol (anhydrous ethanol), and biodiesel from used frying oil and from soybean oil. For the case of biodiesel, its complete life cycle and the closed carbon cycle (photosynthesis) were considered. With data provided by the Brazilian Association of Automotive Vehicle Manufacturers (ANFAVEA) for the number of vehicles produced in Brazil, the emissions of CO2 for the national fleet in 2007 were obtained per type of fuel. With data provided by the Brazilian Department of Transit (DENATRAN) concerning the number of diesel vehicles in the last five years in Brazil, the total CO2 emissions and the percentage that they would decrease in the case of use of pure biodiesel, B100, or several mixtures, B2, B5 and B20, were calculated. Estimates of CO2 emissions for a future scenario considering the mixtures B5 and B20 are also included in this article. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved.

Preparation and characterization of cellulose/hydrous niobium oxide hybrid

A composite of cellulose extracted from bagasse with Nb2O5 center dot nH(2)O in three different proportions (16.67, 37.5 and 50.0 wt%) was prepared using the co-precipitation method. The materials were characterized by X-ray diffractometry (XRD), Fourier transform infra-red spectroscopy (FTIR), thermogravimetric analysis (TG/DTG), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). TG data obtained show that the presence of inorganic material influenced slightly the stability of the hybrid material. The precipitation of 16.67 wt.% of oxide was sufficient to inhibit the combustion peaks present in the DSC curve of cellulose. This work will help find new applications for these materials. Published by Elsevier Ltd.

Efeito do grupo genético sobre as características de carcaça e maciez da carne fresca e maturada de bovinos superprecoces

Objetivou-se estudar o efeito das diferentes proporções de sangue Simental e Nelore sobre as características da carcaça e da carne de bovinos superprecoces. Foram utilizados 72 bovinos jovens inteiros (18 Nelore; 18 ½ Simental × Nelore; 18 Simbrasil e 18 Simental), com 8 meses de idade e 250 kg PV médio inicial. Os animais foram desmamados aos 8 meses de idade em sistema creep-feeding e posteriormente confinados durante 150 dias até atingirem o peso de abate, acima de 465 kg, e abatidos em frigorífico comercial. Os valores de pH e temperatura durante o resfriamento das carcaças foi semelhante para todos os grupos genéticos. da mesma forma, as variáveis carcaça fria, dianteiro e traseiro, não apresentaram diferenças entre os grupos genéticos. Os cortes foram bastante homogêneos, com excessão do contrafilé e do filé-mignon, que foram maiores nos animais Simental. Os animais da raça Nelore e ½ Simental apresentaram maior força de cisalhamento (4,98 e 4,45 kgf) em relação aos Simental e Simbrasil (3,13 e 3,33 kgf). No entanto, após a maturação da carne durante sete dias, não se constataram diferenças entre os valores de maciez entre os grupos. As perdas por evaporação e gotejamento foram maiores na carne in natura para os animais Simental e Simbrasil, no entanto, aos sete dias de maturação se tornaram semelhantes. O sistema de produção de bovinos superprecoces produz carcaças e cortes semelhantes entre as diferentes raças estudadas. Aos sete dias de maturação, a maciez da carne de animais Nelore foi semelhante à dos demais grupos genéticos utilizados neste estudo.

Evaluation of the propylene glycol association on some physical and chemical properties of mineral trioxide aggregate

Duarte MAH, Alves de Aguiar K, Zeferino MA, Vivan RR, Ordinola-Zapata R, Tanomaru-Filho M, Weckwerth PH, Kuga MC. Evaluation of the propylene glycol association on some physical and chemical properties of mineral trioxide aggregate. International Endodontic Journal, 45, 565570, 2012. Abstract Aim To evaluate the influence of propylene glycol (PG) on the flowability, setting time, pH and calcium ion release of mineral trioxide aggregate (MTA). Methodology Mineral trioxide aggregate was mixed with different proportions of PG, as follows: group 1: MTA + 100% distilled water (DW); group 2: MTA + 80% DW and 20% PG; group 3: MTA + 50% DW and 50% PG; group 4: MTA + 20% DW and 80% PG; group 5: MTA + 100% PG. The ANSI/ADA No. 57 was followed for evaluating the flowability and the setting time was measured by using ASTM C266-08. For pH and calcium release analyses, 50 acrylic teeth with root-end cavities were filled with the materials (n = 10) and individually immersed in flasks containing 10 mL deionized water. After 3 h, 24 h, 72 h and 168 h, teeth were placed in new flasks and the water in which each specimen was immersed had its pH determined by a pH metre and the calcium release measured by an atomic absorption spectrophotometer with a calcium-specific hollow cathode lamp. Data were analysed by using one-way anova test for global comparison and by using Tukeys test for individual comparisons. Results The highest value of flowability was observed with MTA + 20% DW and 80% PG and the lowest values were found with MTA + 100% DW. They were significantly different compared to the other groups (P < 0.05). The presence of PG did not affect the pH and calcium release. The MTA + 100% PG favoured the highest (P < 0.05) pH and calcium release after 3 h. Increasing the PG proportion interfered (P < 0.05) with the setting time; when used at the volume of 100% setting did not occur. Conclusion The addition of PG to MTA-Angelus increased its setting time, improved flowability and increased the pH and calcium ion release during the initial post-mixing periods. The ratio of 80% DW 20% PG is recommended.

Oil-in-water lecithin-based microemulsions as a potential delivery system for amphotericin B

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