25 research outputs found

    Joining with industry: innovative curriculum materials for technology and science for primary schools

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    There is a perceived need for curriculum materials that would support primary teachers taking up work placements. Primary classroom materials of this kind should encourage children to be innovative, develop analytical and problem solving skills and be pro-active towards their own learning. The rationale for the development of such a pack of curriculum materials for primary technology and science is discussed in relation to the educational and curriculum contexts of the materials and the ways in which innovative qualities can be developed in children through the use of 'real' contexts for classroom based work. The way in which product analysis can be used to facilitate understanding of innovation in the world of work is examined and some exemplar activities are provided

    Computer‐assisted assessment: suggested guidelines for an institutional strategy

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    Online Learning examines the influence of new technologies on online pedagogy and provides an authoritative synthesis of existing research in the field. It also investigates the direction of e-Learning in the digital age

    Anion Distribution, Structural Distortion, and Symmetry-Driven Optical Band Gap Bowing in Mixed Halide Cs2SnX6 Vacancy Ordered Double Perovskites.

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    Mixed anion compounds in the Fm3̅m vacancy ordered perovskite structure were synthesized and characterized experimentally and computationally with a focus on compounds where A = Cs+. Pure anion Cs2SnX6 compounds were formed with X = Cl, Br, and I using a room temperature solution phase method. Mixed anion compounds were formed as solid solutions of Cs2SnCl6 and Cs2SnBr6 and a second series from Cs2SnBr6 and Cs2SnI6. Single phase structures formed across the entirety of both composition series with no evidence of long-range anion ordering observed by diffraction. A distortion of the cubic A2BX6 structure was identified in which the spacing of the BX6 octahedra changes to accommodate the A site cation without reduction of overall symmetry. Optical band gap values varied with anion composition between 4.89 eV in Cs2SnCl6 to 1.35 eV in Cs2SnI6 but proved highly nonlinear with changes in composition. In mixed halide compounds, it was found that lower energy optical transitions appeared that were not present in the pure halide compounds, and this was attributed to lowering of the local symmetry within the tin halide octahedra. The electronic structure was characterized by photoemission spectroscopy, and Raman spectroscopy revealed vibrational modes in the mixed halide compounds that could be assigned to particular mixed halide octahedra. This analysis was used to determine the distribution of octahedra types in mixed anion compounds, which was found to be consistent with a near-random distribution of halide anions throughout the structure, although some deviations from random halide distribution were noted in mixed iodide-bromide compounds, where the larger iodide anions preferentially adopted trans configurations

    Stigma of Seeking Psychological Services: Examining College Students Across Ten Countries/Regions

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    © Division of Counseling Psychology of the American Psychological Association. Stigma is an important barrier to seeking psychological services worldwide. Two types of stigma exist: public stigma and self-stigma. Scholars have argued that public stigma leads to self-stigma, and then self-stigma is the primary predictor of attitudes toward seeking psychological services. However, this assertion is largely limited to U.S. samples. The goal of this research was to provide a first step in understanding the relationship between public stigma, self-stigma, and attitudes toward seeking psychological services in international contexts (N = 3,276; Australia, Brazil, Canada, Hong Kong, Portugal, Romania, Taiwan, Turkey, United Arab Emirates, and United States). Using structural equation modeling, we found that self-stigma mediated the relationship between public stigma and attitudes toward seeking services among college students in each country and region. However, differences in path strengths emphasize the need to pay attention to the role of public and self-stigma on attitudes toward seeking psychological services throughout the world

    Einfluss der Verarbeitungstechnologie und Werkstoffzusammensetzung auf die Struktur-Eigenschafts-Beziehungen von thermoplastischen Nanoverbundwerkstoffen

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    Die Einarbeitung von nanoskaligen FĂŒllstoffen zur Steigerung von polymeren Eigenschaftsprofilen ist sehr viel versprechend und stĂ¶ĂŸt daher heutzutage sowohl in der Forschung als auch in der Industrie auf großes Interesse. Bedingt durch ausgeprĂ€gte OberflĂ€chen und hohe AnziehungskrĂ€fte, liegen Nanopartikel allerdings nicht singulĂ€r sondern als PartikelanhĂ€ufungen, so genannten Agglomeraten oder Aggregaten, vor. Zur Erzielung der gewĂŒnschten Materialverbesserungen gilt es, diese aufzuspalten und homogen in der polymeren Matrix zu verteilen. Bei thermoplastischen Kunststoffen ist die gleichlĂ€ufige Doppelschneckenextrusion eines der gĂ€ngigsten Verfahren zur Einarbeitung von Additiven und FĂŒllstoffen. Aus diesem Grund war es Ziel dieser Arbeit, mittels dieses Verfahrens verbesserte Verbundwerkstoffe mit Polyamid 66- und Polyetheretherketon-Matrix, durch Einarbeitung von nanoskaligem Titandioxid (15 und 300 nm), zu generieren. In einem ersten Schritt wurden die verfahrenstechnischen Parameter, wie Drehzahl und Durchsatz, sowie die ProzessfĂŒhrung und damit deren Einfluss auf die Materialeigenschaften beleuchtet. Der spezifische Energieeintrag ist ausschlaggebend zur Deagglomeration der Nanopartikel. Dieser zeigte leichte AbhĂ€ngigkeiten von der Drehzahl und dem Durchsatz und verursachte bei der Einarbeitung der Partikel keine wesentlichen Unterschiede in der Aufspaltung der Partikel sowie gar keine in den resultierenden mechanischen Eigenschaften. Die ProzessfĂŒhrung wurde unterteilt in Mehrfach- und Einfachextrusion. Die Herstellung eines hochgefĂŒllten Masterbatches, dessen mehrfaches Extrudieren und anschließendes VerdĂŒnnen, fĂŒhrte zu einer sehr guten Deagglomeration und stark verbesserten Materialeigenschaften. Mittels Simulation des Extrusionsprozesses konnte festgestellt werden, dass das Vorhandensein von ungeschmolzenem Granulat in der Verfahrenszone zu einer Schmelze/Nanopartikel/ Feststoffreibung fĂŒhrt, die die Ursache fĂŒr eine sehr gute Aufspaltung der Partikel zu sein scheint. Durch Modifikation des Extrusionsprozesses erreichte die Einfachextrusion annĂ€hernd den Grad an Deagglomeration bei Mehrfachextrusion, wobei die Materialien bei letzterem Verfahren die besten Eigenschaftsprofile aufwiesen. In einem zweiten Schritt wurde ein Vergleich der EinflĂŒsse von unterschiedlichen PartikelgrĂ¶ĂŸen und –gehalten auf die polymeren Matrizes vollzogen. Die 15 nm Partikel zeigten signifikant bessere mechanische Ergebnisse auf als die 300 nm Partikel, und die Wirkungsweise des 15 nm Partikels auf Polyetheretherketon war stĂ€rker als auf Polyamid 66. Es konnten Steigerungen in Steifigkeit, Festigkeit und ZĂ€higkeit erzielt werden. Rasterelektronenmikroskopische Aufnahmen bestĂ€tigten diese Ergebnisse. Eine Berechnung der Plan-Selbstkosten von einem Kilogramm PEEK-Nanoverbundwerkstoff im Vergleich zu einem Kilogramm unverstĂ€rktem PEEK verdeutlichte, dass ein Material kreiert wurde, welches deutlich verbesserte Eigenschaften bei gleichem Preis aufweist. Zusammenfassend konnte in dieser Arbeit ein tieferes VerstĂ€ndnis des Extrusionsvorganges zur Herstellung von kostengĂŒnstigen und verbesserten Thermoplasten durch das Einbringen von Nanopartikeln gewonnen werden

    Problems with using a supervisor's report as a form of summative assessment

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    The place of a supervisor report when used as a summative assessment of clinical workplace based learning is discusse

    Anion Distribution, Structural Distortion, and Symmetry-Driven Optical Band Gap Bowing of Mixed Halide Cs2SnX6 Vacancy Ordered Double Perovskites

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    Mixed anion compounds in the Fm-3m vacancy ordered perovskite structure were synthesised and characterised experimentally and computationally with a focus on compounds where A = Cs+. Pure anion Cs2SnX6 compounds were formed with X = Cl, Br and I using a room temperature solution phase method. Mixed anion compounds were formed as solid solutions of Cs2SnCl6 and Cs2SnBr6 and a second series from Cs2SnBr6 and Cs2SnI6. Single phase structures formed across the entirety of both composition series, with no evidence of long range anion ordering observed by diffraction. A distortion of the cubic A2BX6 structure was identified in which the spacing of the BX6 octahedra changes to accommodate the A site cation without reduction of overall symmetry. Optical band gap values varied with anion composition between 4.89 eV in Cs2SnCl6 to 1.35 eV in Cs2SnI6, but proved highly non-linear with changes in composition. In mixed halide compounds it was found that lower energy optical transitions appeared that were not present in the pure halide compounds, and this could be attributed to lowering of the local symmetry within the tin halide octahedra. The electronic structure was characterised by photoemission spectroscopy, and Raman spectroscopy revealed vibrational modes in the mixed halide compounds that could be assigned to particular mixed halide octahedra. This analysis was used to determine the distribution of octahedra types in mixed anion compounds, which was found to be consistent with a near-random distribution of halide anions throughout the structure, although some deviations from random halide distribution were noted in mixed iodide-bromide compounds, where the larger iodide anions preferentially adopted trans configurations
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