1000 resultados para Pesticidas - Formulação


Relevância:

20.00% 20.00%

Publicador:

Resumo:

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

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work evaluated the use of the Hildebrand/Hansen solubility parameters for selection of solvents for extraction of the organochlorine pesticides pp' DDT, pp' DDE, Aldrin and a-Endossulfan from soil using columns packed with Al2O3. The mixtures hexane:dichloromethane (7:3; v/v), hexane:acetonitrile (1:1; v/v), hexane:acetone (1:1; v/v) and pure hexane were chosen as extracting solutions. In the addition and recovery tests, different extraction solutions provided high recoveries percentages (>75%) with coefficients of variation below 15%. The recoveries are in agreement with the Hildebrand/Hansen parameters, demonstrating its applicability in the selection of extracting solution and in the replacement of toxic solvents, as dichloromethane

Relevância:

20.00% 20.00%

Publicador:

Resumo:

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

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper evaluates the presence of organochlorinated pesticides in the water supply system of the city of Bauru, State of São Paulo, Brazil. Soil samples were collected in agricultural areas and water samples at several points of the water source (river) and the distribution net. The results of the analyses of the water from the source were compared with the Brazilian classification system for inland waters (CONAMA/86) and the results of analyses of treated water were compared with Brazilian standards for finished drinking water.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A discussion about groundwater contamination is presented in this work. Contamination by agricultural activity, more specifically by pesticides is emphasized. Indirect and direct estimates could be used to predict pesticide behavior in soil, and consequently, to evaluate the potential of groundwater contamination. These results could be applied to advise about the possibility of groundwater contamination by pesticides, and to provide subsidies for making decisions more quickly and efficiently.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

O estudo avaliou a coerência do ideário do Programa UNI, em três projetos no Brasil, analisando a relação entre Propósitos, Métodos e Organização, à luz do Postulado de Coerência de Mario Testa. Bibliografia sobre o Programa UNI e entrevistas com doze atores do seu processo, agrupados como Formuladores do Programa UNI, Diretores de Projetos UNI e Avaliadores, compuseram o material empírico. Este foi recortado, sistematizado e analisado segundo categorias analíticas de determinação, condicionamento, sujeito coletivo e paradigma e segundo categorias empíricas de propósito, método e organização. Evidenciou-se uma formulação idealizada do espaço real de operacionalização dos Projetos e a presença de linhas de determinação e condicionamento construídas, dialeticamente, no espaço concreto de atuação dos atores e na relação entre sujeito e objeto, algumas vezes, em sentido contrário ao que previamente se supôs na formulação do Programa. A investigação conseguiu identificar movimentos de mudanças nas realidades dos Projetos UNI, tanto na universidade, como nos serviços de saúde e comunidade. As limitações presentes no referencial teórico funcionalista, adotado na formulação inicial do Programa e na pouca valorização dada às linhas de condicionamento ou determinação que partem das organizações podem ser apontadas como explicações para o não alcance de sua eficácia plena.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A rapid and efficient analytical method is presented for the quantitative analysis of 10 organochlorine pesticides in corn meal. The extraction and clean up steps are combined into one step by transferring the sample to a chromatographic column prepacked with alumina and silica gel. The pesticides are eluted with n-hexane-dichloromethane 9:1 (v/v) and the extracts analized by gas-liquid chromatography with electron capture detection, the average recoveries were between 78% and 98% and the detection limits were between 1 and 5 ng/g.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The utilization of dentifrices with low fluorine concentration, for children under 6 years of age, has been suggested to reduce the risks of dental fluorosis. However, in order to have anticariogenic potential, the dentifrice should form loosely-bound fluorine (CaF2) on dental enamel. Considering that the formation of CaF2 is a function inversely related to pH, dentifrices with pH 5.5, with 275, 550 and 1,100 ppm F (NaF/silica) were developed in order to assess dose-response effects. A comparison between those dentifrices, a placebo product and the Crest toothpaste (positive control - standard) was carried out. Furthermore, the bioavailability of dentifrices, in terms of formation of total fluorine (TF), CaF2, and fluorapatite (FA) on human dental enamel, was evaluated. An ion-specific electrode was utilized for the determination of the dosage of fluorine. The results revealed that the dentifrice with 550 ppm F was more effective than both the placebo and the dentifrice with 275 ppm, presenting no difference in relation to the positive control (p > 0.05). A dose-effect correlation was observed as to the CaF2 formed. In conclusion, the modified formulation with 550 ppm F can be considered as effective as the standard dentifrice with 1,100 ppm, and its utilization would be safer with regard to dental fluorosis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present study aimed to analyze the action of some acaricides, fungicides, insecticides and herbicides containing different active ingredients on Metarhizium anisopliae Metsch. (Sorokin) inoculated into autoclaved soil. The action of the pesticides was evaluated based on the fungal respiratory activity. The first assessment was done at 48h after inoculation. The pesticides were then added and respiratory activity was determined nine times every 48h and an additional five times every 4 days. Except for the fungicides, no significant effect (P > 0.05) of the pesticides on M. anisopliae was observed. A reduction in CO2 production was observed for the mancozeb treatment from day 4 to day 6 of incubation, and for tebuconazol between days 4 and 6, 8 and 10, and 32 and 36. The same was observed for copper oxychloride between days 10 and 12 and 32 and 36, and for chlorothalonyl between 8 and 10, 10 and 12, and 32 and 36 days of incubation. Identical effect occurred for the acaricides abamectin and fenbutatin oxide, with a reduction in CO2 production between 20 and 24 days of incubation. The herbicides glyphosate, trifluralin and ametrin reduced the respiratory activity of the fungus between days 10 and 12, while the insecticide trichlorfon reduced respiratory activity only from 32 to 40 days of incubation. The results indicate that the toxic action of pesticides on the fungus in soil is small, suggesting that this pest control bioagent can be used in combination with pesticides without compromising its activity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A rapid and reliable method for the determination of 25 compounds selected from four classes of pesticides in samples of fresh apples, grapes, pears, and strawberries purchased at a local supermarket, is presented. The study describes two different methods of extraction: solid-liquid extraction with acetone and supercritical fluid extraction. Clean-up was based on aminopropyl cartridge extraction followed by gas chromatography with an electron capture detector for simultaneous determinations. Confirmatory analysis was carried out by gas chromatography with mass spectrometry in the selected-ion monitoring (SIM) mode. Extraction efficiencies were directly compared and the methods were applied to the analysis of real samples. Recoveries for a majority of pesticides from standard samples at enrichment levels of 0.04-0.10 mg/ kg ranged from 77 to 96 % for both methods. The supercritical fluid extraction method showed good limits of detection (less than 0.01 mg/kg, depending on the pesticide and matrix) as well as minimizing environmental concerns, time, and laboratory effort. © 2006 Centro de Información Tecnológica.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Gymnema sylvestre extract (GSE) is a plant product widely used as an adjuvant in the treatment of diabetes mellitus and commercially available as a powder. Owing to its low flowability, the manufacturing of hard gelatin capsules containing GSE faces specific problems. The purpose of this study was to investigate the best excipient (starch, lactose or microcrystalline cellulose) for hard gelatin capsules containing GSE. The technological properties such us bulk density (ρβ); tapped density (ρt); inter-particle porosity (Ie); Carr index (CI); Hausner ratio (HR); loss on drying (%LOD) and particle size distribution (%Pf) of the various GSE mixtures were investigated with the aim of identifying the best excipient. The need for lubricants (talc/magnesium stearate) was also assessed. GSE was characterized as a fine powder with more than 50% of its particles between 0.149mm to 0.250mm; furthermore, CI=25.6%; RH=1.3 and Ie = 25.6% and, as expected with such properties, it showed poor flowability. All the excipients investigated were able to change the technological properties of GSE and the powder mixture containing microcrystalline cellulose gave the best results.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article aims to present a list of the main influences experimented by architects and urbanists to formulate an urban thought of Sao Paulo City. This way, it will be discussed the main issues raised between the first decades of the XX Century until the 1950s, trying to foresee how the engineers and architects worked to incorporate the urbanistic proposals from Europe and the United States. On the first three sections of this article, it will be presented the concepts that effectively impacted the paulista urban thought of the first half of the XX Century: Sanitarism, the pendulum design: between the Mesologic Theory and the Microbian Theory; Camillo Sitte's historicist formulation; Howard Garden Town and the French experience. Our analysis was formulated by having as a reference a broad and systematic literature, documents stored at Arquivo Histórico Municipal de Araraquara (SP), visits to Faculdade de Arquitetura e Urbanismo da USP Library and to Faculdade de Ciências e Letras da Unesp, Araraquara. The analysis shows that two urbanistic planner streams that happened in São Paulo State were clearly influenced by the conceptions that led the urbanistic debates in the first half of the XX Century. So, these conceptions compose a painting of the urban interventions in São Paulo City.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

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

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)