Synthesis and characterization of COPPER(II) 4´-phenyl-terpyridine compounds and catalytic application for aerobic oxidation of benzylic alcohols

The reactions between 4'-phenyl-terpyridine (L) and nitrate, acetate or chloride Cu(II) salts led to the formation of [Cu(NO3)(2)L] (1), [Cu(OCOCH3)(2)L]center dot CH2Cl2 (2 center dot CH2Cl2)and [CuCl2L]center dot[Cu(Cl)(mu-Cl)L](2) (3), respectively. Upon dissolving 1 in mixtures of DMSO-MeOH or EtOH-DMF the compounds [Cu(H2O){OS(CH3)(2)}L]-(NO3)(2) (4) and [Cu(HO)(CH3CH2OH)L](NO3) (5) were obtained, in this order. Reaction of 3 with AgSO3CF3 led to [CuCl(OSO2CF3)L] (6). The compounds were characterized by ESI-MS, IR, elemental analysis, electrochemical techniques and, for 2-6, also by single crystal X-ray diffraction. They undergo, by cyclic voltammetry, two single-electron irreversible reductions assigned to Cu(II) -> Cu(I)and Cu(I) -> Cu(0) and, for those of the same structural type, the reduction potential appears to correlate with the summation of the values of the Lever electrochemical EL ligand parameter, which is reported for the first time for copper complexes. Complexes 1-6 in combination with TEMPO (2,2,6,6-tetramethylpiperidinyl-1-oxyl radical) can exhibit a high catalytic activity, under mild conditions and in alkaline aqueous solution, for the aerobic oxidation of benzylic alcohols. Molar yields up to 94% (based on the alcohol) with TON values up to 320 were achieved after 22 h.

A remote engineering solution for automating a roller hearth kiln

Remote engineering (also known as online engineering) may be defined as a combination of control engineering and telematics. In this area, specific activities require computacional skills in order to develop projects where electrical devives are monitored and / or controlled, in an intercative way, through a distributed network (e.g. Intranet or Internet). In our specific case, we will be dealing with an industrial plant. Within the last few years, there has been an increase in the number of activities related to remote engineering, which may be connected to the phenomenon of the large extension experienced by the Internet (e.g. bandwith, number of users, development tools, etc.). This increase opens new and future possibilities to the implementation of advance teleworking (or e-working) positions. In this paper we present the architecture for a remote application, accessible through the Internet, able to monitor and control a roller hearth kiln, used in a ceramics industry for firing materials. The proposed architecture is based on a micro web server, whose main function is to monitor and control the firing process, by reading the data from a series of temperature sensors and by controlling a series of electronic valves and servo motors. This solution is also intended to be a low-cost alternative to other potential solutions. The temperature readings are obtained through K-type thermopairs and the gas flow is controlled through electrovalves. As the firing process should not be stopped before its complete end, the system is equipped with a safety device for that specific purpose. For better understanding the system to be automated and its operation we decided to develop a scale model (100:1) and experiment on it the devised solution, based on a Micro Web Server.

InOx thin films deposited by plasma assisted evaporation: application in light shutters

An integration of undoped InOx and commercial ITO thin films into laboratory assembled light shutter devices is made. Accordingly, undoped transparent conductive InOx thin films, about 100 nm thick, are deposited by radiofrequency plasma enhanced reactive thermal evaporation (rf-PERTE) of indium teardrops with no intentional heating of the glass substrates. The process of deposition occurs at very low deposition rates (0.1-0.3 nm/s) to establish an optimized reaction between the oxygen plasma and the metal vapor. These films show the following main characteristics: transparency of 87% (wavelength, lambda = 632.8 nm) and sheet resistance of 52 Omega/sq; while on commercial ITO films the transparency was of 92% and sheet resistance of 83 Omega/sq. The InOx thin film surface characterized by AFM shows a uniform grain texture with a root mean square surface roughness of Rq similar to 2.276 nm. In contrast, commercial ITO topography is characterized by two regions: one smoother with Rq similar to 0.973 nm and one with big grains (Rq similar to 3.617 nm). For the shutters assembled using commercial ITO, the light transmission coefficient (Tr) reaches the highest value (Tr-max) of 89% and the lowest (Tr-min) of 1.3% [13], while for the InOx shutters these values are 80.1% and 3.2%, respectively. Regarding the electric field required to achieve 90% of the maximum transmission in the ON state (E-on), the one presented by the devices assembled with commercial ITO coated glasses is 2.41 V/mu m while the one presented by the devices assembled with InOx coated glasses is smaller, 1.77 V/mu m. These results corroborate the device quality that depends on the base materials and fabrication process used. (C) 2014 Elsevier Ltd. All rights reserved.

Application of fractional algorithms in the control of a robotic bird

In this paper, it is studied the dynamics of the robotic bird in terms of time response and robustness. It is analyzed the wing angle of attack and the velocity of the bird, the tail influence, the gliding flight and the flapping flight. The results are positive for the construction of flying robots. The development of computational simulation based on the dynamic of the robotic bird should allow testing strategies and different algorithms of control such as integer and fractional controllers.

A debugging engine for parallel and distributed programs

Dissertação apresentada para a obtenção do Grau de Doutor em Informática pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia.

Educational application of remote experimentation for mobile devices

In this article the authors describe the application development RExMobile and the importance of remote experimentation via mobile devices, especially smartphones simple, beyond the space provided for this application in education. The article deals the creation, software and hardware that provide an interactive and dynamic way to attract more students to use these experiments remote, serving as support to teachers to science teaching from its initial series. The ease and availability of smartphones, even these students of basic education, permits the reach of new users and in different places. Thus, the practice of remote experimentation in mobile devices enables new spaces for access and interaction. Are used for developing software free or low cost, HTML5 and jQuery Mobile framework, that enable the creation of pages compatible with different mobile operating systems such as iOS, Android, Windows Phone, some Symbian, among others. Also are demonstrated patterns layouts that allow greater accessibility.

Tuning and application of integer and fractional order PID controllers

Fractional calculus (FC) is widely used in most areas of science and engineering, being recognized its ability to yield a superior modeling and control in many dynamical systems. In this perspective, this article illustrates two applications of FC in the area of control systems. Firstly, is presented a methodology of tuning PID controllers that gives closed-loop systems robust to gain variations. After, a fractional-order PID controller is proposed for the control of an hexapod robot with three dof legs. In both cases, it is demonstrated the system's superior performance by using the FC concepts.

SmART: an application reconfiguration framework

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do Grau de Mestre em Engenharia Informática.

Suporte à computação paralela e distribuída em Java: distribuição e execução de trabalho

Nos últimos anos começaram a ser vulgares os computadores dotados de multiprocessadores e multi-cores. De modo a aproveitar eficientemente as novas características desse hardware começaram a surgir ferramentas para facilitar o desenvolvimento de software paralelo, através de linguagens e frameworks, adaptadas a diferentes linguagens. Com a grande difusão de redes de alta velocidade, tal como Gigabit Ethernet e a última geração de redes Wi-Fi, abre-se a oportunidade de, além de paralelizar o processamento entre processadores e cores, poder em simultâneo paralelizá-lo entre máquinas diferentes. Ao modelo que permite paralelizar processamento localmente e em simultâneo distribuí-lo para máquinas que também têm capacidade de o paralelizar, chamou-se “modelo paralelo distribuído”. Nesta dissertação foram analisadas técnicas e ferramentas utilizadas para fazer programação paralela e o trabalho que está feito dentro da área de programação paralela e distribuída. Tendo estes dois factores em consideração foi proposta uma framework que tenta aplicar a simplicidade da programação paralela ao conceito paralelo distribuído. A proposta baseia-se na disponibilização de uma framework em Java com uma interface de programação simples, de fácil aprendizagem e legibilidade que, de forma transparente, é capaz de paralelizar e distribuir o processamento. Apesar de simples, existiu um esforço para a tornar configurável de forma a adaptar-se ao máximo de situações possível. Nesta dissertação serão exploradas especialmente as questões relativas à execução e distribuição de trabalho, e a forma como o código é enviado de forma automática pela rede, para outros nós cooperantes, evitando assim a instalação manual das aplicações em todos os nós da rede. Para confirmar a validade deste conceito e das ideias defendidas nesta dissertação foi implementada esta framework à qual se chamou DPF4j (Distributed Parallel Framework for JAVA) e foram feitos testes e retiradas métricas para verificar a existência de ganhos de performance em relação às soluções já existentes.

Assessment and optimization of wind energy integration into the power systems: application to the portuguese system

The increasing integration of wind energy in power systems can be responsible for the occurrence of over-generation, especially during the off-peak periods. This paper presents a dedicated methodology to identify and quantify the occurrence of this over-generation and to evaluate some of the solutions that can be adopted to mitigate this problem. The methodology is applied to the Portuguese power system, in which the wind energy is expected to represent more than 25% of the installed capacity in a near future. The results show that the pumped-hydro units will not provide enough energy storage capacity and, therefore, wind curtailments are expected to occur in the Portuguese system. Additional energy storage devices can be implemented to offset the wind energy curtailments. However, the investment analysis performed show that they are not economically viable, due to the present high capital costs involved.

Autonomic Activities in the Execution of Scientific Workflows: Evaluation of the AWARD Framework

Workflows have been successfully applied to express the decomposition of complex scientific applications. However the existing tools still lack adequate support to important aspects namely, decoupling the enactment engine from tasks specification, decentralizing the control of workflow activities allowing their tasks to run in distributed infrastructures, and supporting dynamic workflow reconfigurations. We present the AWARD (Autonomic Workflow Activities Reconfigurable and Dynamic) model of computation, based on Process Networks, where the workflow activities (AWA) are autonomic processes with independent control that can run in parallel on distributed infrastructures. Each AWA executes a task developed as a Java class with a generic interface allowing end-users to code their applications without low-level details. The data-driven coordination of AWA interactions is based on a shared tuple space that also enables dynamic workflow reconfiguration. For evaluation we describe experimental results of AWARD workflow executions in several application scenarios, mapped to the Amazon (Elastic Computing EC2) Cloud.

Remote experimentation: integrating research, education, and industrial application

This paper presents a low-cost scaled model of a silo for drying and airing cereal grains. It allows the control and monitor of several parameters associated to the silo's operation, through a remote accessible infrastructure. The scaled model consists of a 2.50 m wide × 2.10 m long plant with all control and monitor capacities provided by micro-Web servers. An application running on the micro-Web servers enables storing all parameters in a data basis for later analysis. The implemented model aims to support a remote experimentation facility for technological education, research-oriented tutorials, and industrial applications. Given the low-cost requirement, this remote facility can be easily replicated in other institutions to support a network of remote labs, which encompasses the concurrent access of several users (e.g. students).

Plataforma web de informação automobilística

Esta dissertação enquadra-se no âmbito dos Sistemas de Informação, em concreto, no desenvolvimento de aplicações Web, como é o caso de um website. Com a utilização em larga escala dos meios tecnológicos tem-se verificado um crescimento exponencial dos mesmos, o que se traduz na facilidade com que podem ser encontradas na Internet diversos tipos de plataformas informáticas. Além disso, hoje em dia, uma grande parte das organizações possui o seu próprio sítio na Internet, onde procede à divulgação dos seus serviços e/ou produtos. Pretende-se com esta dissertação explorar estas novas tecnologias, nomeadamente, os diagramas UML - Unified Modeling Language e a concepção de bases de dados, e posteriormente desenvolver um website. Com o desenvolvimento deste website não se propõe a criação de uma nova tecnologia, mas o uso de diversas tecnologias em conjunto com recurso às ferramentas UML. Este encontra-se organizado em três fases principais: análise de requisitos, implementação e desenho das interfaces. Na análise de requisitos efectuou-se o levantamento dos objectivos propostos para o sistema e das necessidades/requisitos necessários à sua implementação, auxiliado essencialmente pelo Diagrama de Use Cases do sistema. Na fase de implementação foram elaborados os arquivos e directórios que formam a arquitectura lógica de acordo com os modelos descritos no Diagrama de Classes e no Diagrama de Entidade-Relação. Os requisitos identificados foram analisados e usados na composição das interfaces e sistema de navegação. Por fim, na fase de desenho das interfaces foram aperfeiçoadas as interfaces desenvolvidas, com base no conceito artístico e criativo do autor. Este aperfeiçoamento vai de encontro ao gosto pessoal e tem como objectivo elaborar uma interface que possa também agradar ao maior número possível de utilizadores. Este pode ser observado na maneira como se encontram distribuídas as ligações (links) entre páginas, nos títulos, nos cabeçalhos, nas cores e animações e no seu design em geral. Para o desenvolvimento do website foram utilizadas diferentes linguagens de programação, nomeadamente a HyperText Markup Language (HTML), a Page Hypertext Preprocessor (PHP) e Javascript. A HTML foi utilizada para a disposição de todo o conteúdo visível das páginas e para definição do layout das mesmas e a PHP para executar pequenos scripts que permitem interagir com as diferentes funcionalidades do site. A linguagem Javascript foi usada para definir o design das páginas e incluir alguns efeitos visuais nas mesmas. Para a construção das páginas que compõem o website foi utilizado o software Macromedia Dreamweaver, o que simplificou a sua implementação pela facilidade com que estas podem ser construídas. Para interacção com o sistema de gestão da base de dados, o MySQL, foi utilizada a aplicação phpMyAdmin, que simplifica o acesso à base de dados, permitindo definir, manipular e consultar os seus dados.

Application of a control banding tool for risk level assessment and control of nanoparticles exposure in welding operations

Scope of study: welding operations result in harmful emissions of nanoparticles; the aim of emissions monitorisation is to evaluate exposure levels and to derive protection measures in order to protect exposed workers; however, the traditional approach of comparing measured concentrations with exposure limits cannot be used; but risk levels can be quantified by using Control Banding Strategies.

Optimization process of polyester polymer mortars modified with recycled GFRP waste aggregates – application of factorial experiment design-

Glass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both: cross-linked nature of thermoset resins, which cannot be remolded, and complex composition of the composite itself, which includes glass fibres, matrix and different types of inorganic fillers. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. There are several methods to recycle GFR thermostable materials: (a) incineration, with partial energy recovery due to the heat generated during organic part combustion; (b) thermal and/or chemical recycling, such as solvolysis, pyrolisis and similar thermal decomposition processes, with glass fibre recovering; and (c) mechanical recycling or size reduction, in which the material is subjected to a milling process in order to obtain a specific grain size that makes the material suitable as reinforcement in new formulations. This last method has important advantages over the previous ones: there is no atmospheric pollution by gas emission, a much simpler equipment is required as compared with ovens necessary for thermal recycling processes, and does not require the use of chemical solvents with subsequent environmental impacts. In this study the effect of incorporation of recycled GFRP waste materials, obtained by means of milling processes, on mechanical behavior of polyester polymer mortars was assessed. For this purpose, different contents of recycled GFRP waste materials, with distinct size gradings, were incorporated into polyester polymer mortars as sand aggregates and filler replacements. The effect of GFRP waste treatment with silane coupling agent was also assessed. Design of experiments and data treatment were accomplish by means of factorial design and analysis of variance ANOVA. The use of factorial experiment design, instead of the one factor at-a-time method is efficient at allowing the evaluation of the effects and possible interactions of the different material factors involved. Experimental results were promising toward the recyclability of GFRP waste materials as polymer mortar aggregates, without significant loss of mechanical properties with regard to non-modified polymer mortars.