Determinação do teor alcoólico da cachaça: uma abordagem das propriedades intensivas

The Resolution number 3 of the Câmara de Educação Básica (CEB)/Conselho Nacional de Educação (CNE), published in 1998, June 26 (BRASIL, 1998), which established the National Curriculum Guidelines for High School Education, emphasizes the interdisciplinarity, in its 8th Article. However, almost fourteen years later, the reality in most of our schools is the adoption of a merely disciplinary methodology, vis-à-vis the difficulty related to educational planning activities of this kind. In this paper, we present a proposal of an interdisciplinary experimental activity that addresses the concept of surface tension, connecting physicists and chemists. The idea is that students determine the alcohol content of “cachaça” and discuss the concepts of surface tension forces between equal molecules, similar and different.

Determinação do teor alcoólico de vodcas: uma abordagem multidisciplinar no ensino da física, química e matemática

In this paper, it is proposed an experimental activity to be developed with high school students, addressing the concepts of density and surface tension from a multidisciplinary approach among Physics, Chemistry and Mathematics. In this proposal, students are challenged to determine the alcohol content of vodkas from intensive physical properties of liquids. Two calibration curves were obtained, one for density and another for surface tension as a function of ethanol concentration in water. The alcohol levels obtained from these properties were very close to the values given by manufacturers, due the similarity of these beverages with ethanol-water binary mixtures.

Metabolismo nutricional em Atta sexdens rubropilosa Forel, 1908: voo nupcial, fundação e desenvolvimento da colônia

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Determinação do teor dos ingredientes ativos imidacloprida e clorpirifós em produtos técnicos formulados por CLUE-DAD

The use of pesticides to manage pest problems in agriculture has become a common practice around the world. Pesticides consist in chemical substances or biological agents that act preventing, destroying, repelling or mitigating the damage caused by pests in agriculture. In order to a successful treatment, the correct dosage of pesticide has to be applied for each kind of culture. In this context, this project aims to quantify the levels of the active ingredients Imidacloprid and Chlorpyrifos present in formulated technical products and compare with the reported in the ir commercial leaflets. The analyzes were performed by Ultra Performance Liquid Chromatography coupled to a photodiode array detector (CLUE-DAD). The identification of Imidacloprid and Chlorpyrifos in the samples was realized by comparison of the time of retention and UV spectre of those substances with the commercials patterns, resulting in a excellent method specificity of the method. In the scope of determination of active ingredients in formulated products, the method developed showed good sensitivity in the applied conditions, with suitables limits of detection (4,2.10-² mg L-¹ for Imidacloprid and 1,1.10-¹ mg L-¹ to Chlorpyrifos) and quantitation (1,4.10-¹ mg L-¹ and Imidacloprid 3,6.10-¹ mg L-¹ to Chlorpyrifos) for the concentrations found in matrices analyzed. Furthermore, good results were obtained to the method accuracy with coeficiente of variance values in the range of 0,6 to 0,7% for repeatability (intra-day) and 0,4 to 0,58% for intermediate precision (inter- day). The accuracy of the method was determined by recovery tests, the values were comprised in the range of 98 102%. According to the recommendations of the Associação Brasileira de Normas Técnicas, these values show good accuracy of the method. The concentrations obtained in the quantification of the active ingredients in formulated products showed values within permited by ABNT, 60.1% (w/v) ± 0.6%...

Valores nutricionais e qualitativos de carnes bovinas (Longissimus thoracis) provenientes de sistemas de produção orgânica e convencional

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Produtividade, teor foliar e exportação de nutrientes em cultivares de batata

The right choose of the cultivar influences greatly the potato yield. It is very important to know its agronomic behavior in the region where it is planted, as well its nutritional status, in order to supply the best package in the fertilization operations. In this work the tuber yield, the nutritional status of plants and the exportation of nutrients were studied in eighteen potato cultivars. A randomized blocks experimental design, with four replicates, was used. Mondial showed the highest total and commercial yields. The nutrient concentrations in fourth leaf of potato plant followed the decreasing order: N>K>Ca>P>Mg>B>Zn. The exportation of nutrients by the tubers followed the decreasing order: K>N>P>Mg>Ca. B and Zn had different behavior according the cultivars.

Teor e acúmulo de nutrientes em grãos de feijão comum em semeadura direta, sob déficit hídrico

O feijão comum possui notória importância socioeconômica, constitui uma das mais importantes fontes proteicas da dieta brasileira e juntamente com o arroz, proporciona uma dieta mais vantajosa e equilibrada em termos de aminoácidos. O objetivo desse trabalho foi avaliar o efeito das combinações de diferentes reposições hídricas nas fases vegetativa - I e reprodutiva - II, durante o ciclo do feijoeiro IAC Alvorada, e comparar o teor nutricional dos grãos. Foi utilizado o delineamento em blocos casualizados, com quatro repetições em fatorial 4 x 4, sendo quatro níveis de déficit hídrico 100, 80, 60 e 40% da evapotranspiração da cultura (ETc) e os mesmos níveis foram repetidos em duas fases de desenvolvimento da cultura do feijão (fases I e II). Cada parcela possuía as dimensões de 4 m x 1,8 m, totalizando 7,2 m2 de 0,45 m. Inicialmente irrigou-se pelo sistema aspersão convencional em um período de 60 minutos diariamente, posteriormente o sistema adotado foi por gotejamento, conforme cada tratamento de restrição hídrica. Avaliaram-se os teores nutricionais de macro (N, P, K, Ca, Mg e S) e micronutrientes (B, Cu, Fe, Mn e Fe). A interação entre as lâminas nas fases I e II influenciou nos teores de micronutrientes Fe e S em grãos de feijão. Houve aumento dos teores de Fe e diminuição dos teores de Cu, Mn e B com a deficiência hídrica em uma das fases. Os macro e micronutrientes mais extraídos foram N, P, K, Fe, B e Mn. O N e o P são os nutrientes exportados em maior quantidade pelos grãos.

Determinação do teor de glicose em bagaço de cana-de-açúcar hidrolizado pelo processo de conversão enzimática

The production of ethanol and sugar from sugarcane juice generate as byproduct, the bagasse. Currently, the bagasse, an industrial lignocellulosic biomass, can be used for production of second-generation ethanol, since when it is submitted to hydrolytic processes generates fermentable sugars. The objective of this study was to produce fungal enzymes capable of hydrolyzing this lignocellulosic biomass to generate glucose. For this, we used the mushroom species Lentinula edodes, Pleurotus ostreatus, Pleurotus eryngii, and Pycnoporus sanguineus as potential sources of laccase, manganese peroxidase and lignin peroxidase enzymes, capable of hydrolyzing the crushed sugarcane. The hydrolysis process was performed with the highest enzymatic activities observed from laccase in L. edodes (39.23 U-mL after 25 day incubation), P. ostreatus (2.5 U U-mL after 27 day incubation), P. sanguineus (80 U-mL after 27 days of incubation) and P. eryngii (16.45 U-mL 15 days incubation). MnP and LiP showed no significant results. The enzymatic hydrolysis of sugarcane bagasse in natura (32,17% hemicellulose, cellulose 52,45% and 10,62% lignin) and bagasse hydrolyzate with 7,0% H2SO4 (0,20% hemicellulose, 68,82% to 25,33% cellulose and lignin) were evaluated for each enzymatic obtained. Compared to others, the enzymes produced by P. sanguineus incubated in sugarcane bagasse showed better efficiency resulting in glucose with an average content of 0,14 g-L. Although the levels of glucose determined in this work were low in relation to the literature, it can be stated that the laccase, manganese peroxidase and lignin peroxidase enzymes demonstrated good hydrolytic potential, especially those produced by the fungus P. sanguineus.

Filossilicatos: efeitos no crescimento e na nutrição de plantas de milho e no teor de silício do solo

Importance of silicon fertilization is related to the benefits that silicon is able to promote tolerance to heavy metals, reduce the incidence of pests and diseases, increased productivity, drought tolerance, among others. The objective of this study was to evaluate the phyllosilicates effect on biomass formation, nutrients and silicon on the early stages of corn plants compared to wollastonite. Experiment was installed and conducted in a greenhouse located at the Universidade Estadual Paulista, UNESP, in Registro, SP. Consisting of 10 treatments established in a randomized block design in scheme factorial (2 x 5), with five replications. First factor corresponds to the two types of soil (Oxisol and Ultisol) and the second factor, five treatments (control, 0 kg ha-1 Si; wollastonite W13, 13 kg ha-1 Si; wollastonite W26, 26 kg ha-1 Si; phyllosilicates F13, 13 kg ha-1 Si; phyllosilicates F26, 26 kg ha-1 Si). In Ultisol, phyllosilicates increased production of fresh, dry biomass and silicon content in shoots of corn compared to treatment with wollastonite and control. Highest Si content compared to control (6.2 g kg-1) was obtained with 13 kg ha-1 Si of phyllosilicates (9.8 g kg-1). The greatest accumulation mass and Si in plants by applying phyllosilicates were observed in Ultisol, although this display Si content higher than Oxisol.

Produção de biomassa e teor de cumarina em folhas de guaco (Mikania laevigata Sch. Bip. ex Baker) em diferentes idades da planta

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)