Study of photo-assisted electrochemical degradation of carbaryl at dimensionally stable anodes (DSA (R))

This paper presents the results concerning the degradation of the pesticide carbaryl comparing two methods: electrochemical (EC) and photo-assisted electrochemical (PAEC). The experimental variables of applied current density, electrolyte flow-rate and initial carbaryl concentration were investigated. The results demonstrate that the electrochemical degradation of carbaryl was greatly enhanced when simultaneous UV light was applied. The greatest difference between the PAEC and EC method was apparent when lower current densities were applied. The extent of COD removal was much enhanced for the combined method, independent of the applied current density. It should be noted that the complete removal of carbaryl was achieved with out the need to add NaCl to the reaction mixture, avoiding the risk of chlorinated organic species formation. (C) 2009 Elsevier B.V. All rights reserved.

Determination of polyamines in organic extracts from roots of Canavalia ensiformis by capillary electrophoresis

A rapid, selective and specific capillary zone electrophoresis method to determine polyamines in organic extracts from roots of Canavalia ensiformis (Jack Beans) was developed using ultra violet (UV) detection. Canavalia ensiformis is relatively free from diseases and it is used as reference in allelopathy studies. Polyamines are widely distributed in plant and it could be involved in plant pathogen interactions. Optimal separation was achieved using 15 mmol.L-1formic acid (pH 3.0) + 4 mmol.L-1 imidazole as a background electrolyte. It was possible to identify and quantify the polyamines on herbal samples in the presence of other phytochemical substances and analyze them quickly (up to 6 min). The applicability of this method was evaluated in crude organic extracts from roots of Canavalia ensiformis.

Evaluation of the QuEChERS Method and Gas Chromatography-Mass Spectrometry for the Analysis Pesticide Residues in Water and Sediment

A method for the determination of pesticide residues in water and sediment was developed using the QuEChERS method followed by gas chromatography - mass spectrometry. The method was validated in terms of accuracy, specificity, linearity, detection and quantification limits. The recovery percentages obtained for the pesticides in water at different concentrations ranged from 63 to 116%, with relative standard deviations below 12%. The corresponding results from the sediment ranged from 48 to 115% with relative standard deviations below 16%. The limits of detection for the pesticides in water and sediment were below 0.003 mg L(-1) and 0.02 mg kg(-1), respectively.

One rapidly growing market of Sweden: organic food : A qualitative study portraying some consumers’ decision to purchase organic food

In recent years there has been a significantly rising trend amongst consumers for health and environmental issues, which has resulted in greater attention for and sales of organic food. Organic food production strives to use natural resources, such as land, energy and water in a sustainable way and the products does not contain artificial fertilizers or chemical pesticides. However, organic food products are also often more expensive and less available in comparison to conventional food products. Despite this, interest for and sales of organic food products have increased around the globe, and in Sweden particularly, the increase in sales has grown largely from an international perspective. This thesis is of qualitative character and is focused on studying some consumers from the Swedish market of organic food. The purpose of this thesis is to contribute with a better understanding on the buying decision process regarding organic food purchase. To achieve this, the authors have studied some consumers that purchase organic food and have searched for patterns that could be identified in the decision process. The consumer buying decision process model has been used for portrayal of the chosen consumers’ decision to purchase organic food products. Interviews with six Swedish consumers were conducted, whereas each respondent continuously purchase organic food products. Results show that the purchase of organic food products begins with discovering an unsatisfied need state, which the consumers of this study desired to change with the purchase of organic food products. This study show how six consumers reason when passing through the stages of the buying decision process, in order to satisfy their desired need state. The authors found that the respondents feel satisfied with purchasing organic food products, which lead them in to continuously buying these products. Altogether, the findings contribute with knowledge that can come to be helpful when wanting to understand more about the consumer decision to purchase organic food.

Mercury content of tobacco products

Mercury contamination of food products results from contact with soil, water, and air polluted with mercury from industrial sources, as well as from the use of mercury-containing pesticides and fungicides on plants. A method was developed for extracting mercury from tobacco products. The mercury content of various tobacco products was determined, using an atomic absorption spectrophotometer.

Burocracias em ação: múltiplos atores, estratégias e conflitos na regulação federal de agrotóxicos

Esta tese busca analisar a atuação de burocracias na implementação de políticas públicas em um ambiente de múltiplios principals, stakeholders e agentes, por meio de um estudo de caso sobre a regulação federal de agrotóxicos, atribuída a três órgãos distintos – MAPA, ANVISA e IBAMA. O referencial teórico foi construído a partir das teorias de controle político da burocracia, teorias de fontes do poder burocrático e da literatura sobre implementação de políticas públicas. O formato da legislação e o nível de complexidade da política dão aos órgãos atribuições exclusivas e inúmeros espaços de autonomia, ao mesmo tempo em que lhes obriga a decidir de forma consensuada. As burocracias adotam diversas estratégias para minimizar a assimetria de informação e o risco moral por parte do setor regulado. Os principals políticos se valem de diversos instrumentos para impor suas preferências, mas o fazem de forma superficial ou esporádica. A baixa efetividade desta influência é explicada mais pelas limitações dos principals do que pela resistência dos agentes. Poder Judiciário e Ministério Público podem ser importantes parceiros ou pontos de veto à ação regulatória dos órgãos. O estilo de liderança dos gestores e a visão sobre qual deve ser o papel da burocracia em uma política regulatória explicam as diferenças observadas nos órgãos no tocante à busca de alianças e à ação estratégica perante os demais atores.

A tributação como um dos instrumentos à sustentabilidade ambiental

A presente monografia versa sobre o papel da tributação como instrumento da sustentabilidade ambiental. Para tanto, utiliza-se como exemplo, a contrário senso, o Convênio CONFAZ n°.100/97, que reduz a zero a base de cálculo do Imposto sobre Circulação de Mercadorias e Prestação de Serviços Interestaduais e Intermunicipais e de Comunicações (ICMS) nas saídas dos defensivos agrícolas. Posteriormente, analisa-se brevemente o poder de tributar e suas limitações, bem como o benefício fiscal do ICMS, e em especial, do Convênio CONFAZ supracitado. Por fim, examina-se a sustentabilidade sob o viés jurídico, econômico e sistêmico, em cotejo com a tributação no contexto da sustentabilidade ambiental.

Expressão da ética na assistência de enfermagem aos jovens intoxicados

Analisar sobre o processo de cuidar da equipe de enfermagem na visão dos usuários intoxicados por tentativa de suicídio. Metodologia: estudo descritivo exploratório, de abordagem qualitativa, realizada em um centro de assistência ao intoxicado da Paraíba/Brasil, com nove usuários. Como critérios de inclusão, participaram as pessoas que tentaram o suicídio por intoxicação, nos meses de abril e maio de 2010, período de coleta de dados do estudo, e que tivessem condições de responder as questões formuladas. A coleta de dados foi realizada por meio de entrevista semiestruturada com uso de formulário, cujos dados foram tratados pela Análise Temática. A pesquisa foi aprovada conforme avaliação do Comitê de Ética em Pesquisa da UEPB e mediante CAAE nº 0003.0.349.133-10. Resultados: os participantes concentraram-se na faixa etária de 14 a 26 anos, predominando o gênero feminino e o consumo de agrotóxicos na tentativa de suicídio. A análise dos discursos permitiu identificar que todos os integrantes demonstraram-se satisfeitos com a assistência de enfermagem, entretanto, apontaram ausência de comunicação com os profissionais cuidadores e atraso para a realização dos procedimentos. Conclusão: a ética na assistência de enfermagem supõe o estabelecimento da valorização do humano durante as atribuições profissionais, proporcionando o bem-estar daqueles que não enxergam a dádiva maior, que é nesse plano, a vida

Obtenção de álcool alílico (PROP-2-EN-1-OL) a partir da glicerina derivada do biodiesel de óleo de mamona

In this work, biodiesel was produced from castor oil that was a byproduct glycerin. The molar ratio between oil and alcohol, as well as the use of (KOH) catalyst to provide the chemical reaction is based on literature. The best results were obtained using 1 mol of castor oil (260g) to 3 moles of methyl alcohol (138g), using 1.0% KOH as catalyst at a temperature of 260 ° C and shaken at 120 rpm. The oil used was commercially available, the process involves the reaction of transesterification of a vegetable oil with methyl alcohol. The product of this reaction is an ester, biodiesel being the main product and the glycerin by-product which has undergone treatment for use as raw material for the production of allyl alcohol. The great advantage of the use of glycerin to obtain allyl alcohol is that its use eliminates the large amount of waste of the biodiesel and various forms of insult to the environment. The reactions for the formation of allyl alcohol was conducted from formic acid and glycerin in a ratio 1/1, at a temperature of 260oC in a heater blanket, being sprayed by a spiral condenser for a period of 2 hours and the product obtained contains mostly the allylic alcohol .. The monitoring of reactions was performed by UV-Visible Spectrophotometer: FTIR Fourier transform, the analysis showed that these changes occur spectrometer indicating the formation of the product allylic alcohol (prop-2-en-1-ol) in the presence of water, This alcohol was appointed Alcohol GL. The absorption bands confirms that the reaction was observed in (υ C = C) 1470 -1600 cm -1 and (υ CO), 3610-3670 attributed to C = C groups and OH respectively. The thermal analysis was carried out in a thermogravimetric analyzer SDT Q600, where the mass and temperature are displayed against time, that allows checking the approximate rate of heating. The innovative methodology developed in the laboratory (LABTAM, UFRN), was able to treat the glycerine produced by transesterification of castor oil and used as raw material for production of allyl alcohol, with a yield of 80%, of alcohol, the same is of great importance in the manufacture of polymers, pharmaceuticals, organic compounds, herbicides, pesticides and other chemicals

Efeito da associação do herbicida clomazone a nanoesferas de alginato/quitosana na sorção em solos

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

Preliminary studies on the effects of d-limonene to workers of the leaf-cutting ant Atta sexdens rubropilosa and its implications for control

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Weed interference on maize (Zea mays) under no tillage system

A field trial was carried out in Brazil in March 2002 with the aim to evaluate the effects of different timing and extension of weedy period on maize productivity. The hybrid Pioneer 30K75 was sowed under 7 t ha(-1) mulching promoted by glyphosate spraying. The treatments were divided in two groups: In the first group, weeds were maintained since the maize sowing until different periods in the crop cycle: 0, 14, 28, 42, 56, 70, and 150 days (harvesting time). In the second group, the maize crop was kept weed free for the same periods of the first group. Weed control was done through hand hoeing. A complete randomized blocks experimental design with five replications was used for plots distribution in the field. Nonlinear regression model was used to study the effects of weedy or weedfree periods on maize productivity. Weed community included 13 families and 31 species. Asteraceae, Poaceae, and Euphorbiaceae were the most abundant families. Results showed that under no tillage condition with 7 t ha-1 mulching at sowing time, the maize crop could cohabit with weed community for 54 days without any yield lost. on the other hand, if the crop was kept weed free for 27 days, the weed interference was not enable to reduce maize production. According to these results one weed control measure between 27 and 54 days after crop emergence could be enough to avoid any reduction in maize productivity.

Influence of type and amount of straw cover on weed emergence

This research was undertaken during 2003-2004 growing season to evaluate the effects of type [forage sorghum hybrid Cober Exp (Sorghum bicolor x Sorghum sudanense), forage millet (Pennisetum americanum var. BN2), finger millet (Eleusine coracana), and St Lucia grass (Brachiaria brizantha)] and amount of straw cover (5.5 and 3.0 t ha(-1)) upon the emergence of Bidens pilosa, Chamaesyce spp., Amaranthus spp., and Commelina benghalensis, under field conditions of the Brazilian Cerrado, in the region of Uberlandia-MG. The control consisted additional treatment lacking the straw cover. Emergence of weed depended on the type and amount of straw cover, as well as the weed species. The lowest number of B. pilosa seedlings was found in the presence of forage sorghum straw; Chamaesyce spp. in the lack of straw; Amaranthus spp. in the presence of higher amount of forage sorghum and forage millet, and lower amounts of forage millet and Finger Millet. All the types and amounts of straw reduced the emergency of C. benghalensis, except at the lowest level of St Lucia grass and the lack of straw.