9 research outputs found

    A high-throughput, solvent free method for dispersing metal atoms directly onto supports

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    Atomically-dispersed metal catalysts (ADMCs) on surfaces have demonstrated high activity and selectivity in many catalytic reactions. However, dispersing and stabilising individual atoms in support materials in an atom/energy-efficient scalable way still presents a significant challenge. Currently, the synthesis of ADMCs involves many steps and further filtration procedures, creating a substantial hurdle to their production at industrial scale. In this work, we develop a new pathway for producing ADMCs in which Pt atoms are stabilised in the nitrogen-interstices of a graphitic carbon nitride (g-C3N4) framework using scalable, solvent-free, one-pot magnetron sputtering deposition. Our approach has the highest reported rate of ADMC production of 4.8 mg h1 and generates no chemical waste. Deposition of only 0.5 weight percent of Pt onto g-C3N4 led to improved hydrogen production by factor of ca. 3333 450 when compared to bare g-C3N4. PL analysis showed that the deposition of Pt atoms onto g-C3N4 suppressed the charge carrier recombination from the photogenerated electron–hole pairs of Pt/g-C3N4 thereby enhance hydrogen evolution. Scanning transmission electron microscope imaging before and after the hydrogen evolution reaction revealed that the Pt atoms stabilised in g-C3N4 have a high stability, with no agglomeration observed. Herein, it is shown that this scalable and clean approach can produce effective ADMCs with no further synthetic steps required, and that they can be readily used for catalytic reactions

    Inserção de alunos com deficiência no ensino regular: perfil da cidade de Marília Inclusion of students with disabilities in regular school: profile of the city of Marília

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    Objetivou-se com esse estudo identificar o perfil de professores de ensino regular da cidade de Marília que tinham alunos com deficiências matriculados em suas salas de aula, bem como o perfil da clientela atendida por estes professores. Participaram do estudo 68 professores da cidade de Marília - SP que tinham alunos com deficiência matriculados em suas salas. O instrumento de coleta de dados utilizado foi um questionário contendo 13 questões divididas em 2 partes: 1) identificação dos participantes e 2) identificação dos alunos com deficiência. Os dados colhidos nos questionários foram submetidos à análise da freqüência absoluta e relativa. Foram identificadas 10 categorias. De acordo com os resultados dessa pesquisa, concluiu-se que a inserção do aluno com deficiência no ensino regular ocorre com a modificação da formação que favorece ao profissional o conhecimento e a compreensão das distintas formas de aprendizagem do seu alunado, a fim de estruturar sua própria prática pedagógica para atender, com qualidade, a diversidade.<br>The aim of this study was to identify the profile of regular school teachers of Marília-SP, who have students with disabilities registered in their classrooms, as well as to identify the clientele these teachers were working with. Sixty eight teachers participated in the study in the city of Marília - SP, all of whom had students with disabilities in their classrooms. The instrument used to collect data was a questionnaire with 13 questions divided in 2 parts: 1) identification of participants and 2) identification of students with disabilities. The data was submitted to analysis of absolute and relative frequency. Ten categories were identified. We were able to conclude, based on the results of the study, that the inclusion of students with disabilities in regular school occurs due to changes in teacher development that enable professionals to acquire knowledge and understanding of the distinct ways in which their students learn. Such knowledge helps them to be better structure their pedagogical practice so as to answer to student diversity with quality teaching

    Cost effects of hospital mergers in Portugal

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    The Portuguese hospital sector has been restructured by wide-ranging hospital mergers, following a conviction among policy makers that bigger hospitals lead to lower average costs. Since the effects of mergers have not been systematically evaluated, the purpose of this article is to contribute to this area of knowledge by assessing potential economies of scale to explore and compare these results with realized cost savings after mergers. Considering the period 2003-2009, we estimate the translog cost function to examine economies of scale in the years preceding restructuring. Additionally, we use the difference-in-differences approach to evaluate hospital centres (HC) that occurred between 2004 and 2007, comparing the years after and before mergers. Our findings suggest that economies of scale are present in the pre-merger configuration with an optimum hospital size of around 230 beds. However, the mergers between two or more hospitals led to statistically significant post-merger cost increases, of about 8 %. This result indicates that some HC become too large to explore economies of scale and suggests the difficulty of achieving efficiencies through combining operations and service specialization
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