17,850 research outputs found
Impactite and pseudotachylite from Roter Kamm Crater, Namibia
Pseudotachylite is known to occur in a variety of geologic settings including thrust belts (e.g., the Alps and the Himalayas) and impact craters such as Roter Kamm, Namibia. Controversy exists, however, as to whether pseudotachylite can be produced by shock brecciation as well as by tectonic frictional melting. Also open to debate is the question of whether pseudotachylites form by frictional fusion or by cataclasis. It was speculated that the pseudotachylite at Roter Kamm was formed by extensional settling and adjustment of basement blocks during 'late modification stage' of impact. The occurrence of pseudotachylite in association with rocks resembling quenched glass bombs and melt breccias in a relatively young crater of known impact origin offers a rare opportunity to compare features of these materials. Petrographic, x-ray diffraction, and electron microprobe analyses of the impactites and pseudotachylites are being employed to determine the modes of deformation and to assess the role of frictional melting and comminution of adjacent target rocks
Enhancing teacher education practice through professional learning conversations
The paper discusses the value of peer observation followed by professional learning conversations for the professional development of teacher educators. The authors analyse their shared learning experiences and articulate what challenged them in these experiences. They discuss the ways in which their perceptions of this process differed or were similar. The grounding of the experience in a context of trust and professional relationship was seen as an essential part of the learning process. The authors highlight the importance of the cognitive-emotional and personal-professional aspects of teacher educators' lives in supporting their learning through the combination of peer observation and ongoing professional learning conversations. © 2008 Association for Teacher Education in Europe
The Third Way for the Third Sector: Using Design to Transfer Knowledge and Improve Service in a Voluntary Community Sector Organisation
This paper describes a two-year Knowledge Transfer Partnership that concluded in September 2011. Knowledge Transfer Partnerships (KTP) is a UK-wide activity that helps organisations to improve their competitiveness and productivity by making better use of knowledge, technology and skills within universities, colleges and research organisations. This paper details the outcome of a KTP between Age UK Newcastle and Northumbria University’s School of Design that aimed to use Design approaches to improve the charity’s services. This paper will describe the recent context for organisations operating in the Voluntary Community Sector and discuss the relevance of a Design approach to both the improvement of customer services in this circumstance, as well as the transfer of knowledge to a capacity-starved organisation. It will also document how Design was used to achieve both of these aims, and the resulting impact of this engagement on the organisation and stakeholders
WFPC2 LRF Imaging of Emission Line Nebulae in 3CR Radio Galaxies
We present HST/WFPC2 Linear Ramp Filter images of high surface brightness
emission lines (either [OII], [OIII], or H-alpha+[NII]) in 80 3CR radio
sources. We overlay the emission line images on high resolution VLA radio
images (eight of which are new reductions of archival data) in order to examine
the spatial relationship between the optical and radio emission. We confirm
that the radio and optical emission line structures are consistent with weak
alignment at low redshift (z < 0.6) except in the Compact Steep Spectrum (CSS)
radio galaxies where both the radio source and the emission line nebulae are on
galactic scales and strong alignment is seen at all redshifts. There are weak
trends for the aligned emission line nebulae to be more luminous, and for the
emission line nebula size to increase with redshift and/or radio power. The
combination of these results suggests that there is a limited but real capacity
for the radio source to influence the properties of the emission line nebulae
at these low redshifts (z < 0.6). Our results are consistent with previous
suggestions that both mechanical and radiant energy are responsible for
generating alignment between the radio source and emission line gas.Comment: 80 pages, 54 figures. Accepted for publication in ApJ
Retaining effective early career teachers in NSW schools
This project was commissioned by the NSW Department of Education and Training. This four and a half year research project had the aims of tracking a cohort of final year (2005) preservice teacher education students through their post-graduation experience into 2006, 2007, 2008 and 2009, in order to understand more clearly the reasons why some early career teachers (ECTs) in NSW public schools choose to leave the profession, and why others choose to remain; and in order to develop strategies to increase the retention rate of effective teachers during their early years of teaching
The physical and chemical characteristics of lards and other fats in relation to their culinary value I. Shortening value in pastry and cookies
These studies on the relationship of the physical and chemical characteristics and constants of lards and other fats to their culinary value were started during the fall of 1932 and completed during the summer of 1937.
The culinary tests were divided into three groups as follows: 1. The shortening power of lards and other fats in pastry and cookies. 2. the use of lards and other fats in plain cake, 3. the frying life of lards compared with other fats.
This section of the report presents the studies relating to the shortening value of lards as compared with other fats. The work has been done in various units or sections over a period of years by Lowe and the foods research fellows of the Foods and Nutrition Subsection
The physical and chemical characteristics of lards and other fats in relation to their culinary value III. For frying purposes
The main purpose of this study was to compare the frying life of lards and other fats when used under household conditions. Doughnuts and potato chips were cooked in the fats. Certain chemical and physical constants of the fats were determined before and after cooking to find the extent of change during their use. In addition, the amount of fat absorbed by the doughnuts was recorded and an effort made to determine whether the degree of absorption was correlated with the chemical and physical characteristics of these fats, and if so, with which of these characteristics.
In another unit of the study doughnuts were cooked at three temperatures, and the extent of the chemical and physical changes in the fats, due to the temperatures employed, was determined. The doughnuts cooked at these three temperatures were also scored for palatability
EPR identification of defects responsible for thermoluminescence in Cu-doped lithium tetraborate (Li2B4O7) crystals
Electron paramagnetic resonance (EPR) is used to identify the electron and hole traps responsible for thermoluminescence (TL) peaks occurring near 100 and 200 â—¦C in copper-doped lithium tetraborate (Li2B4O7) crystals. As-grown crystals have Cu+ and Cu2+ ions substituting for lithium and have Cu+ ions at interstitial sites. All of the substitutional Cu2+ ions in the as-grown crystals have an adjacent lithium vacancy and give rise to a distinct EPR spectrum. Exposure to ionizing radiation at room temperature produces a second and different Cu2+ EPR spectrum when a hole is trapped by substitutional Cu+ ions that have no nearby defects. These two Cu2+ trapped-hole centers are referred to as Cu2+-VLi and Cu2+active, respectively. Also during the irradiation, two trapped-electron centers in the form of interstitial Cu0 atoms are produced when interstitial Cu+ ions trap electrons. They are observed with EPR and are labeled Cu0A and Cu0B. When an irradiated crystal is warmed from 25 to 150 â—¦C, the Cu2+active centers have a partial decay step that correlates with the TL peak near 100 â—¦C. The concentrations of Cu0A and Cu0B centers, however, increase as the crystal is heated through this range. As the crystal is futher warmed between 150 and 250 â—¦C, the EPR signals from the Cu2+active hole centers and Cu0A and Cu0B electron centers decay simultaneously. This decay step correlates with the intense TL peak near 200 â—¦C
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