4,028 research outputs found

    Supporting Computing Educators to Create a Cycle of Teaching and Computing Education Research

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    Despite a rich history of computing education in the United Kingdom and Ireland, computing educators often rely on the same procedures and teaching practices rather than embrace innovations. Similarly, while a growing collection of literature exists on educational theory and practice in computing education, much of this focuses on the same concepts and concerns. An aspiration is that both these problems can be simultaneously addressed by computing educators adopting a cycle of embracing existing literature when devising teaching practice and then feeding their experience and findings back to the community in a rigorous fashion. Consequently, this panel supports computing educators by acting as advisers on a one-on-one basis to support audience members in discovering or devising their own cycle of teaching practice and computing education research

    Supersolar Ni/Fe production in the Type IIP SN 2012ec

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    SN 2012ec is a Type IIP supernova (SN) with a progenitor detection and comprehensive photospheric-phase observational coverage. Here, we present Very Large Telescope and PESSTO observations of this SN in the nebular phase. We model the nebular [O I] 6300, 6364 lines and find their strength to suggest a progenitor main-sequence mass of 13-15 Msun. SN 2012ec is unique among hydrogen-rich SNe in showing a distinct and unblended line of stable nickel [Ni II] 7378. This line is produced by 58Ni, a nuclear burning ash whose abundance is a sensitive tracer of explosive burning conditions. Using spectral synthesis modelling, we use the relative strengths of [Ni II] 7378 and [Fe II] 7155 (the progenitor of which is 56Ni) to derive a Ni/Fe production ratio of 0.20pm0.07 (by mass), which is a factor 3.4pm1.2 times the solar value. High production of stable nickel is confirmed by a strong [Ni II] 1.939 micron line. This is the third reported case of a core-collapse supernova producing a Ni/Fe ratio far above the solar value, which has implications for core-collapse explosion theory and galactic chemical evolution models.Comment: Published versio

    Effects of Cation Vacancy Distribution in Doped LaMnO3+d Perovskites

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    In this paper we report studies on the correlation between the presence and distribution of cation vacancies in doped manganites (La,M)MnO3+delta (where M = Na, Ca) and their magnetic properties. Results indicate that cation vacancies are distributed differently for the different crystal structures and dopant ion type. In particular it is shown that knowledge of the total vacancies concentration alone is not enough to fully characterize the physical properties of manganites and that their distribution between the A and B sites of the perovskite structure plays a crucial role which should be taken into account in future studies.Comment: 27 pages, 5 figure. To appear in J. Solid State Che
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