Voltammetric analysis of mancozeb and its degradation product ethylenethiourea

The purpose of this work was to develop a reliable alternative method for the determination of the dithiocarbamate pesticide mancozeb (MCZ) in formulations. Furthermore, a method for the analysis of MCZ's major degradation product, ethylenethiourea (ETU), was also proposed. Cyclic voltammetry was used to characterize the electrochemical behavior of MCZ and ETU, and square-wave adsorptive stripping voltammetry (SWAdSV) was employed for MCZ quantification in commercial formulations. It was found that both MCZ and ETU are irreversibly reduced (− 0.6 V and − 0.5 V vs Ag/AgCl, respectively) at the surface of a glassy carbon electrode in a mainly diffusion-controlled process, presenting maximum peak current intensities at pH 7.0 (in phosphate buffered saline electrolyte). Several parameters of the SWAdSV technique were optimized and linear relationships between concentration and peak current intensity were established between 10–90 μmol L− 1 and 10–110 μmol L− 1 for MCZ and ETU, respectively. The limits of detection were 7.0 μmol L− 1 for MCZ and 7.8 μmol L− 1 for ETU. The optimized method for MCZ was successfully applied to the quantification of this pesticide in two commercial formulations. The developed procedures provided accurate and precise results and could be interesting alternatives to the established methods for quality control of the studied products, as well as for analysis of MCZ and ETU in environmental samples.

Controlo de acesso móvel

O mercado de smartphones tem vindo a crescer massivamente nos últimos anos, bem como a diversi cação das suas funcionalidades no dia-a-dia de cada pessoa. O mercado aberto de aplicações para estes equipamentos também tem sofrido uma forte evolução o que permite uma maior qualidade e competitividade pela apresentação de produtos. O conceito de casas inteligentes está cada vez mais presente e é algo que as pessoas se estão a acomodar de forma gradual. Para acompanhar tal feito, é necessário desenvolver as capacidades dos equipamentos que estas pessoas mais usam para que estes possam dar resposta a estas necessidades. Para o caso atual irão ser estudadas as fechaduras inteligentes. Os sistemas comercializados atualmente, são tipicamente sistemas proprietários e apresentam algumas limitações ou faltas (ex: ao nível da segurança, incapacidade de abranger um largo número de dispositivos móveis ou mesmo ao nível do preço). Neste contexto, e com base na caracterização das soluções de controlo de acesso atuais, foi estudada a viabilidade de, usando uma abordagem assente em tecnologias não proprietárias (i.e., abertas), desenvolver soluções de controlo de acesso com características comparáveis com os sistemas proprietários actuais e, eventualmente, ultrapassando os limites e falhas identi cados. Dadas estas premissas o sistema de controlo de acesso móvel pensado envolve um computador BeagleBone Black e a tecnologia sem os Bluetooth. Este sistema permite a fácil integração do computador com qualquer smartphone atual e é dotado de fortes características de segurança e privacidade. O sistema foi concebido inicialmente para ser implementado em fechaduras de portas mas com possibilidade de expansão para outros equipamentos. Além disso, o sistema permitirá também o acesso a terceiros após a devida autorização do dono.

Derivation and consistency checking of models in early software product line engineering

Dissertação para obtenção do Grau de Doutor em Engenharia Informática

Internationalization strategy: HOLOS Mobile - Angola

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Nestle: A marketing plan for a healthy low fat yogurt

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Structural transformation and specialization patterns in the product space: assessing China and India

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

Men’s purchase intention of shampoo: a model based on the theory of planned behavior and self-concept

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Emove

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Commercial vs. product placement: A study with young children

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

The dilution effect: The influence of expertise and abstraction on consumer's judgements of products

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Product communication strategies: Emotional versus rational communication strategies and attitude change on children consumers

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

O Design, a Gestão e a Comunicação da Marca: Caso de estudo spryou

Dissertação apresentada ao Instituto Politécnico de Castelo Branco para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Design Gráfico pela Escola Superior de Artes Aplicadas do Instituto Politécnico de Castelo Branco em associação com a Faculdade de Arquitetura da Universidade de Lisboa.

Business plan analysis of a Brazilian software company

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

The influence of a fun packaging on children’s sensory evaluation of a healthy product

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics