7,842 research outputs found
Infrared Observations of novae in the SOFIA era
Classical novae inject chemically enriched gas and dust into the local
inter-stellar medium (ISM). Abundances in the ejecta can be deduced from
infrared (IR) forbidden line emission. IR spectroscopy can determine the
mineralogy of grains that grow in nova ejecta. We anticipate the impact that
NASA's new Stratospheric Observatory for Infrared Astronomy (SOFIA) will have
on future IR studies of novae.Comment: To appear in the proceedings of "Physics of Evolved Stars 2015 - A
conference dedicated to the memory of Olivier Chesneau
The circumstellar dust of "Born-Again" stars
We describe the evolution of the carbon dust shells around Very Late Thermal
Pulse (VLTP) objects as seen at infrared wavelengths. This includes a 20-year
overview of the evolution of the dust around Sakurai's object (to which Olivier
made a seminal contribution) and FG Sge. VLTPs may occur during the endpoint of
as many as 25% of solar mass stars, and may therefore provide a glimpse of the
possible fate of the Sun.Comment: To appear in the proceedings of "Physics of Evolved Stars 2015 - A
conference dedicated to the memory of Olivier Chesneau
Design and development of a multi-layer memory system Final report, 28 Jan. 1966 - 27 Jan. 1967
Design and development of multilayer memory syste
The Organic Research Centre - Elm Farm:Bulletin 87
Bulletin 87 with coverage of Avian Influenza H5N1 in Suffolk,commentary on Biofuels, a paper on the organic "transition to sustainable resilience",paper on participatory approach to agronomy trials,update on evolutionary breeding of wheat project,article on formation of new growers alliance in UK
Looking for Design in Materials Design
Despite great advances in computation, materials design is still science
fiction. The construction of structure-property relations on the quantum scale
will turn computational empiricism into true design.Comment: 3 pages, 1 figur
The tail of the Jurassic fish Leedsichthys problematicus (Osteichthyes: Actinopterygii) collected by Alfred Nicholson Leeds - an example of the importance of historical records in palaeontology
The specimen of the tail of <i>Leedsichthys problematicus</i>, now in The Natural History Museum, London, was one of the most spectacular fossil vertebrates from the Oxford Clay Formation of Peterborough, but as an isolated find it shares no bones in common with the holotype of the genus and species. However, a letter from Alfred Nicholson Leeds and related documents cast valuable new light on the excavation of the tail, indicating that it was discovered with cranial bones, gill-rakers, and two pectoral fins, thereby including elements that can potentially be compared with those of the holotype. The documents also clearly indicate that The Natural History Museum's specimen is not part of the same individual as any other numbered specimen of <i>Leedsichthys</i> as had been speculated on other occasions. The maximum size of the animal represented by The Natural History Museum's specimen was possibly around 9 metres, considerably less than previous estimates of up to 27.6 metres for <i>Leedsichthys</i>. Historical documentary evidence should therefore be rigorously checked both when studying historical specimens in science, and in preparing text for museum display labels
Study of the volume and spin collapse in orthoferrite LuFeO_3 using LDA+U
Rare earth (R) orthoferrites RFeO_3 exhibit large volume transitions
associated with a spin collapse. We present here ab initio calculations on
LuFeO_3. We show that taking into account the strong correlation among the
Fe-3d electrons is necessary. Indeed, with the LDA+U method in the Projector
Augmented Wave (PAW), we are able to describe the isostructural phase
transition at 50 GPa, as well as a volume discontinuity of 6.0% at the
transition and the considerable reduction of the magnetic moment on the Fe
ions. We further investigate the effect of the variation of U and J and find a
linear dependence of the transition pressure on these parameters. We give an
interpretation for the non-intuitive effect of J. This emphasizes the need for
a correct determination of these parameters especially when the LDA+U is
applied to systems (e.g in geophysical investigations) where the transition
pressure is a priori unknown
The Organic Research Centre; Elm Farm Bulletin 84 July 2006
Regular bulletin with technical updates of the Organic Advisory Service
Issue contains:
Battling on for Avian Flu preventive vaccination; Organic Colombian Blacktail eggs;
UK Co-existence - GMOand non-GMO crops; Aspects of Poultry Behaviour; CAP in the service of biodiversity; Seeing the Wood, the Trees and the Catch 22; Beware of organic market "statistics"; A central role in energy review
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