Zeolites and related materials as catalyst supports for hydrocarbon oxidation reactions

Catalytic oxidation is a key technology for the conversion of petroleum-based feedstocks into useful chemicals (e.g., adipic acid, caprolactam, glycols, acrylates, and vinyl acetate) since this chemical transformation is always involved in synthesis processes. Millions of tons of these compounds are annually produced worldwide and find applications in all areas of chemical industries, ranging from pharmaceutical to large-scale commodities. The traditional industrial methods to produce large amounts of those compounds involve over-stoichiometric quantities of toxic inorganic reactants and homogeneous catalysts that operate at high temperature, originating large amounts of effluents, often leading to expensive downstream processes, along with nonrecovery of valuable catalysts that are loss within the reactant effluent. Due to the increasingly stringent environmental legislation nowadays, there is considerable pressure to replace these antiquate technologies, focusing on heterogeneous catalysts that can operate under mild reactions conditions, easily recovered, and reused. Parallelly, recent advances in the synthesis and characterization of metal complexes and metal clusters on support surfaces have brought new insights to catalysis and highlight ways to systematic catalysts design. This review aims to provide a comprehensive bibliographic examination over the last 10 years on the development of heterogeneous catalysts, i.e., organometallic complexes or metal clusters immobilized in distinct inorganic supports such as zeolites, hierarchical zeolites, silicas, and clays. The methodologies used to prepare and/or modify the supports are critically reviewed, as well as the methods used for the immobilization of the active species. The applications of the heterogenized catalysts are presented, and some case-studies are discussed in detail.info:eu-repo/semantics/publishedVersio

Parenting during the COVID-19 lockdown in Portugal: changes in daily routines, co-parenting relationships, emotional experiences, and support networks

The COVID-19 pandemic challenged parental resources pertinent to coping with lockdowns. The main objective of this work was to study parenting during the COVID-19 lockdown. Specifically at focus were parental behaviors concerning key domains for the family (daily routine, co-parenting, emotional experience, and support network) and changes related to the pandemic and associated with the parents’ employment statuses. An online survey was carried out through an ad hoc questionnaire where participants completed questions about their sociodemographic data and rated how much their family routines, their co-parenting relationship, their emotional experiences, and the support available in the family network varied on a 5-point scale. The participants included 1384 parents, of which 286 responded to open questions regarding impactful experiences during the lockdown. The results showed differences in daily routine, co-parenting, emotional experience, and support network according to the parents’ employment statuses. Between-group comparisons showed that at-home parents caring for children with governmental aids generally revealed more positive parenting behavior changes, while at-home parents who were teleworking reported more difficulties in parent-child activities and co-parenting. Furthermore, the content analysis of the data confirmed how important themes such as family dynamics, professional activities, and the relationship with the school community were throughout the participants’ accounts of gains and losses. Overall, parents’ employment statuses are associated with diverse experiences during lockdown. The COVID-19 pandemic highlighted the importance of family resources and parental resilience, particularly during circumstances jeopardizing the ever-sensitive work-family balance.info:eu-repo/semantics/publishedVersio

The vertebrate Embryo Clock: Common players dancing to a different beat

Vertebrate embryo somitogenesis is the earliest morphological manifestation of the characteristic patterned structure of the adult axial skeleton. Pairs of somites flanking the neural tube are formed periodically during early development, and the molecular mechanisms in temporal control of this early patterning event have been thoroughly studied. The discovery of a molecular Embryo Clock (EC) underlying the periodicity of somite formation shed light on the importance of gene expression dynamics for pattern formation. The EC is now known to be present in all vertebrate organisms studied and this mechanism was also described in limb development and stem cell differentiation. An outstanding question, however, remains unanswered: what sets the different EC paces observed in different organisms and tissues? This review aims to summarize the available knowledge regarding the pace of the EC, its regulation and experimental manipulation and to expose new questions that might help shed light on what is still to unveil.info:eu-repo/semantics/publishedVersio

Heuristic evaluation of the usability of a mechanical ventilator Interface through a simulator

Determining the usability of mechanical ventilator interfaces is vital in ensuring correct usage under critical procedures that can place patients’ health in danger. Heuristic evaluation has been used to evaluate usability in many different areas, including medical devices. The objective of this study is to evaluate the usability of a mechanical ventilator using the heuristic evaluation method. The evaluation of a mechanical ventilator simulator (Drager's Evita V500) was performed using the Heuristic Evaluation System Checklist (HESC). Three evaluators took part in the experiment in assessing the usability through HESC. The results show that of the 292 checklist sub-heuristics included in the HESC Checklist, 127 were compliant (had no flaws), 75 were not compliant (had flaws) and 95 were not applicable. The results point out that the mechanical ventilator interfaces should be improved to avoid human error due to usability issues. The results also show that heuristic evaluation generates a large quantity of objective information, which provides an exhaustive identification of aspects that should be improved.publishe

A review of important cognitive concepts in aviation

Even considering the current low accident rate in aviation, the anticipated growth in the number of airplanes in the air in the next decades will lead to an inadmissible rise in the number of accidents. These have been mostly attributed to human error and a misunderstanding of automation by the crew, especially during periods of high workload and stress in the cockpit. Therefore, increased safety requires not only advances in technology, but improved cockpit design including better human-machine interface. These cannot be achieved however, without considering some of the cognitive constructs that affect the behaviour of pilots in the cockpit. In fact, given its characteristics and public visibility, the flight deck of commercial jets is one of the most common arenas for the study of complex and skilled human performance. Here I present a literature review on the selected topics of workload, situation awareness, stress and automation in the cockpit, with the goal of supporting the development of new technologies

Modification of MOR by desilication treatments: structural, textural and acidic characterization

The effect of several desilication experimental parameters (base concentration, temperature and time) on the characteristics of MOR zeolite was studied. The samples were characterized by X-ray diffraction, Al-27 and Si-29 MAS-NMR, chemical analysis, and FTIR (framework vibration region). The textural characterization was made by N-2 adsorption and the acidity was evaluated by pyridine adsorption followed by FTIR and by the catalytic model reaction of n-heptane cracking. The alkaline treatments promoted the Si extraction from the zeolite framework, without considerable loss of crystallinity and, as it was envisaged, an important increase of the mesoporous structure was attained. A linear correlation between the number of framework Si per unit cell. N-Si and the asymmetric stretching wavenumber, nu(i), was observed. The acidity characterization shows that the desilicated samples exhibit practically the same acid properties than the parent HMOR zeolite. The optimum desilication conditions were those used to obtain sample M/0.2/85/2, i.e., sample treated with 0.2 M NaOH solution at 85 degrees C for 2 h

Analysis of entrepreneurial propensity of students from the Viseu pole of Portuguese Catholic University

Este artigo pretende mostrar a importância do ensino superior na promoção do empreendedorismo. Assim, começa-se com uma análise teórica dos conceitos de empreendedorismo e de empreendedor e dos principais motivos que conduzem ao empreendedorismo, bem como dos obstáculos que o dificultam. Salienta-se também a importância que o ensino superior tem na promoção do empreendedorismo. Faz-se, por fim, uma breve evolução histórica da educação para o empreendedorismo no ensino superior e do que tem sido feito em Portugal nesta área. Em termos metodológicos, apresentam-se os resultados de um estudo efetuado com 348 alunos do Pólo de Viseu da Universidade Católica Portuguesa. Este estudo teve como principal objetivo conhecer a propensão empreendedora dos seus alunos. Os resultados obtidos neste estudo sugerem que os alunos têm pouca tendência empreendedora, o que se poderá dever aos receios e às dificuldades em desenvolver um negócio próprio, assim como a alguns fatores que condicionam a criação e o sucesso de uma empresa. Assim, é fundamental evidenciar a importância do empreendedorismo, quer para os indivíduos, quer para a sociedade, e, por isso, é indispensável fomentar a sua promoção, sobretudo junto da comunidade escolar.This article aims to show the importance of higher education in promoting entrepreneurship. So, we start with a theoretical analysis of the concepts of entrepreneurship and entrepreneur and the main reasons that lead to entrepreneurship, such as the obstacles to it. Also highlight the importance that higher education has to promote entrepreneurship, and, finally, a brief historical development of entrepreneurship education in higher education and what has been done in this area in Portugal. In methodological terms, we present the results of a study conducted with 348 students from Viseu pole of the Portuguese Catholic University. This study aimed to know the entrepreneurial propensity of their students. The results of this study suggest that students have little entrepreneurial trend, which could be due to the fears and difficulties in developing their own business, as well as some factors that influence the creation and success of a company. Thus, it is crucial to highlight the importance of entrepreneurship, both for individuals and for society, and therefore it is essential to foster its promotion especially among the school community.info:eu-repo/semantics/publishedVersio