The thermal decomposition and crystallization behaviour of a sol-gel precursor used for the preparation of c-axis oriented Al-doped ZnO thin films were investigated in the temperature range 20-600°C by TG-DTA, IR spectroscopy and XRD analysis. At low temperature, the formation of ZnO crystallites from the sol precursor, prepared by dissolving Zn(CH 3COO)2·2H2O and AlCl 3·6H2O in 2-methoxyethanol and monoethanol amine, takes place via zinc carbonate hydroxide (sclarite/hydrozincite) and occurs simultaneously with the decomposition of this intermediary compound, which occurs above 150°C. At 200°C, the crystalline structure is well defined in terms of ZnO hexagonal lattice parameters, although an important amount of residual organic compounds and water was not yet removed. Increasing the treatment temperature up to 300, 400 and 600°C leads to a gradual removal of the residual organic compounds and therefore to a small change of the ZnO crystalline structure in terms of lattice parameters and grain size.

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The SiMe3 group (TMS), introduced as a substituent at the cyclopentadienyl ligand, is found to magnify the solubility of the corresponding metal complexes in supercritical carbon dioxide (scCO(2)). This is verified from comparative solubility measurements of the species (eta(5)-Me-3 SiC5H4)MoO2 Cl, 1a, (eta(5)-Me3SiC5H4)(2)ZrCl2, 2a, and (eta(5)-Me3SiC5H4)Co(CO)I-2.0.5(I-2), 3a (newly synthesised), and of their unsubstituted precursors 1b-3b, respectively. In spite of the increased solubility, the chemical, structural and reactivity properties of the TMS derivatives are scarcely affected. Confirmation comes from a detailed study of the cobalt complex 3a that includes X-ray structural determination. The geometry is most similar to that of the precursor 3b while an apparently different Co-CO interaction is observed in the carboxylated analogue [(eta(5)-PhCH2CO2C5H4)Co(CO) I-2, 3c]. The problem is computationally tackled by using the DFT B3LYP method. The optimised geometries of the simplified models of 3a-3c are all very similar. In particular, the computed stretching frequency of the unique CO ligand is consistent with the insignificant influence of the TMS group while it suggests a reduced amount of metal back-donation in 3c. It is inferred that the TMS complexes 1a-3a, while having higher solubility in scCO2, maintain almost unaltered the electronic and chemical features of their parent compounds. In particular, the role of 1a-3a as catalysts, that is well documented for homogeneous solutions, remains unaltered in the very different scCO(2) environment. The assumption is experimentally validated for 1a by performing with the latter two classic catalytic processes. The first process is the oxidation of PPh3 that is achieved by using molecular oxygen as an oxidant. The second example concerns the epoxidation of cyclohexene achieved in presence of tert-butyl hydroperoxide (TBHP).

Energies of two-electron one-photon transitions from initial double K-hole states and the transition energies of competing processes, namely K hyper-satellites, were computed for low-Z elements, using the multi-configuration Dirac–Fock method. Transition rates are also evaluated.

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Superoxide reductases catalyze the monovalent reduction of superoxide anion to hydrogen peroxide. Spectroscopic evidence for the formation of a dinuclear cyano-bridged adduct after K(3)Fe(CN)(6) oxidation of the superoxide reductases neelaredoxin from Treponema pallidum and desulfoferrodoxin from Desulfovibrio vulgaris was reported. Oxidation with K(3)Fe(CN)(6) reveals a band in the near-IR with lambda(max) at 1020 nm, coupled with an increase of the iron content by almost 2-fold. Fourier transform infrared spectroscopy provided additional evidence with CN-stretching vibrations at 2095, 2025-2030, and 2047 cm(-)(1), assigned to a ferrocyanide adduct of the enzyme. Interestingly, the low-temperature electronic paramagnetic resonance (EPR) spectra of oxidized TpNlr reveal at least three different species indicating structural heterogeneity in the coordination environment of the active site Fe ion. Given the likely 6-coordinate geometry of the active site Fe(3+) ion in the ferrocyanide adduct, we propose that the rhombic EPR species can serve as a model of a hexacoordinate form of the active site.

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This article is based on the lesson presented in the scope of academy activities in the area of Sociology (at FCT-UNL). It is intended to approach the controversies concerning the relation between technology and society (technological determinism, effect on employment, importance of the social behaviours in the definition of needs for new products and equipment), and on the most recent trends (over all, since middle of the last century) in terms of technological evolution and of its social and cultural change. Finally, this subject was dedicated to the presentation of the main factors that has lead to the development of the contribution of sociology for the training and education in engineering. Thus, one intends to acquire new elements on this area of knowledge also presented in other schools of engineering of other countries (for examples, United States and Holland), and how the theoretical beddings are been developed since the beginning of 20th century on the modalities of work organization that imply a cooperation between engineering and social sciences.

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Recent studies continue to indicate the existence of a narrow relationship between flexible work organizations and the economic growth, in particular, Sweden and Germany. The measure of this relationship is many times the result of the value added per worker. Therefore, the causes of economic growth must be perceived from the interior of the company (work organization, technology, infrastructures, product design). On the other hand, the capacity of innovation can be perceived by the market through new products and services, and still significant changes with the introduction of new equipment and design of an efficient work organization. In this article it is analyzed the evolution of the productivity and employment levels in Portugal and other European countries, over all, during the decade of 90. An analysis for sector is made still. One verifies often that economic growth can be without employment growth. However, the growth can be obtained when if it reaches bigger added value and the efficiency can be verified when there are diminished costs for a same period of time, although that the labor productivity is also the pointer of the quality of life in a economy, therefore it represents the value produced by the work. Moreover, the total factors productivity is the measure of the technological and organizational progress (don’t includes only the technological investments). It is tried to get and to analyze the available statistics on these dimension in Portugal, concluding that Portugal presents an enterprise structure predominantly based on small and very small companies, a great number of which is market by a weak potential of adaptability, innovation and sustainability. It becomes urgent to take the non-material factors that integrate the productivity dimension, as factors of intervention for a benchmarking that allows a process of sustainable growth.

The Portuguese National Action Plan for Employment (NAP) is the main instrument for the labour market policy. It was adopted in 1998. The NAP transposes to the Portuguese reality the contents of such guidelines, with the adequate adjustments required by the national specificities, establishing objectives, quantified targets and action deadlines, as well as defining new programmes and measures. Therefore, the objectives of the labour market policy were focusing on the promotion of an adequate transition of the youngsters in active life, on the promotion of social and professional insertion and fight against long term unemployment and exclusion, on the improvement of basic and professional qualification of the working population in a perspective of lifelong training, namely as a way to prevent unemployment phenomena, and on the preventive management and follow-up of sectoral restructuring processes.

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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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