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A novel iron(III) porphyrin disulphide derivative have been successfully immobilised on gold surfaces by self-assembly. The redox response of the modified electrodes was compared with the obtained for a similar iron porphyrin in solution, confirming the immobilisation of the metalloporphyrin. The gravimetric data obtained by electrochemical quartz crystal microbalance (EQCM) during adsorption allowed an estimation of the electrode coverage, providing further evidence for the formation of the porphyrin SAM. The modified electrodes were also measured by conventional and imaging ellipsometry. The electrocatalytic activity of the two modified electrodes was tested for the reduction of the molecular oxygen. (C) 2002 Elsevier Science B.V. All rights reserved.

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{A stochastic variational principle for the classical Burgers equation is established. A solution of this equation can be considered as the velocity field of a stochastic process which is a minimum of an energy functional. A family of stochastic constants of the motion, determined in terms of the probability distribution of that process, yields the complete list of symmetries of the Burgers equation.}

Monitoring systems have traditionally been developed with rigid objectives and functionalities, and tied to specific languages, libraries and run-time environments. There is a need for more flexible monitoring systems which can be easily adapted to distinct requirements. On-line monitoring has been considered as increasingly important for observation and control of a distributed application. In this paper we discuss monitoring interfaces and architectures which support more extensible monitoring and control services. We describe our work on the development of a distributed monitoring infrastructure, and illustrate how it eases the implementation of a complex distributed debugging architecture. We also discuss several issues concerning support for tool interoperability and illustrate how the cooperation among multiple concurrent tools can ease the task of distributed debugging.

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In this work, spectroscopic ellipsometry was used to characterise oxide films produced by anodic oxidation of amorphous silicon using an ethylene glycol (0.04 M KNO3) solution. The data obtained show that the growth of the oxide is not only a function of the voltage applied, but also of the current density and of the time process. An empiric model based on a power law is proposed for the growth of the oxide using, as parameters, the voltages and the time process. The oxide produced shows porosity of approximately 12%, which can be reduced down to 6% under well-controlled growth conditions. © 2002 Elsevier Science B.V. All rights reserved.

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Monitoring systems have traditionally been developed with rigid objectives and functionalities, and tied to specific languages, libraries and run-time environments. There is a need for more flexible monitoring systems which can be easily adapted to distinct requirements. On-line monitoring has been considered as increasingly important for observation and control of a distributed application. In this paper we discuss monitoring interfaces and architectures which support more extensible monitoring and control services. We describe our work on the development of a distributed monitoring infrastructure, and illustrate how it eases the implementation of a complex distributed debugging architecture. We also discuss several issues concerning support for tool interoperability and illustrate how the cooperation among multiple concurrent tools can ease the task of distributed debugging.

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In this paper, we present the preliminary results concerning the deposition of highly transparent and conductive gallium-doped zinc oxide (GZO) deposited on transparent flexible substrate based on cellulose derivatives. Prior to the deposition of the GZO film, the surface of the polymer have been coated with a thin silicon dioxide (SiO2) layer deposited by thermal evaporation assisted by an electron gun. By doing this surface treatment, we succeeded in depositing highly conductive and transparent GZO with an electrical resistivity of 2.0 × 10-3 Ω cm and an average optical transmittance in the visible part of the spectrum (400-700 nm) of 70% by r.f. magnetron sputtering at room temperature. Besides the optoelectronic properties, the films are mechanically stable with a polycrystalline structure with a strong preferred (002) orientation, parallel to the substrate. © 2003 Elsevier B.V. All rights reserved.

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A propose for this article is to present information on the emergence of the knowledge field of sociology of work and labor studies in Portugal. The period of 1974-1984 produced an interesting bibliography in the fields of social stratification, labor conflicts and social history. However, and since the mid-1980s, significant changes have emerged. There took place an increased theoretical diversity and also there was a major preoccupation with the development of a more professional teaching of the discipline. At this time, the first graduated specialists in Sociology appeared in the labor market since 1980, working in municipalities, industrial firms, public health institutions, schools, or even in research and development (R&D) units. The Portuguese association in this field (APSIOT) organized many scientific meetings, debates with unionists, managers and politicians, beside the regular publication of review “Organizações e Trabalho” (Organization and Work) since 1989. It started the diffusion of a professional culture of sociologists who associate science and their occupation concerning themselves not only with scientific quality, but also with technical competence and social responsibility. At the same time, one could assist to the participation of sociologists in the social and organizational molding of new technologies in order to promote alternative production systems.

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