We use a continuous 30 day incoherent scatter radar experiment at Millstone Hill in October 2002 to examine day‐to‐day thermospheric variability in exospheric temperature Tex. Solar flux and magnetic ...activity influences as the main driving factors for day‐to‐day variability are investigated quantitatively. Solar ultraviolet flux levels are based on the TIMED/SEE space weather product, allowing for analysis of ultraviolet flux‐Tex correlation. Tex is most sensitive to solar EUV flux with approximately a 2 day delay at wavelengths of 27–34 nm (including 30.4 nm). In particularly, a 20–60 h time delay occurs in Tex response to EUV flux at 27–34 nm band, with shorter delays in the morning and longer delays in the afternoon and at night. The 1 ∼ 2 day delayed Tex response to solar ultraviolet flux and associated thermospheric solar preconditioning (“memory”) are most significant in the daily mean for the 27–34 nm band, in the diurnal and semidiurnal amplitudes for the soft X‐ray flux at 0.1–7 nm, and in the diurnal amplitude for longer wavelengths. An empirical model driven only by EUV flux at 27–34 nm from 2 days in advance reproduces 90% of the observed variability in the Tex daily mean. With a 2 day time delay, solar X‐ray flux at 0.1–7 nm is correlated positively with Tex diurnal amplitude and negatively with Tex semidiurnal amplitude. Finally, magnetic activity control, as represented by the Dst index, is weaker during the day and stronger at night and is important for the semidiurnal amplitude but not important for the daily mean.
Key Points
Correlation analysis between exospheric temperature and EUV at different bands
A 20–60 h time delay in exospheric temperature response to EUV flux
EUV‐only model at 27–34 nm for 2 days in advance produces 90% of DC variability
The Acheulean site of la Noira was fossilized beneath the Fougères fluviatile formation dated by the ESR method at 655 ± 55 ka. Coarse deposits were left at the base after the end of the Cher ...incision and served as raw material deposits for hominins. The occupation level has yielded bifaces, cores and a flake assemblage in lacustrine millstone. The systematic recording of about 6 500 lithic objects brought to light the reasons underlying the presence of the diverse materials, and elucidated hominin choice of lacustrine millstone for knapping flakes and shaping bifacial pieces. The systematic study of all the materials enabled us to advance hypotheses concerning some of the behaviour identified at the site: sorting of raw materials affected by frost, cursory peripheral knapping of slabs of up to a metre long with hammers weighing several kilogrammes, breaking up of large slabs over 10 cm long and displacement of the fragments. This analysis assesses hominin behaviour and the management and exploitation of raw material deposits at 700 ka.
This article has two components; a discussion of an Ireland-wide inventory of millstone quarries and a detailed regional case study in order to study the development of the millstone industry at both ...micro and macro levels. The first component highlights the use of certain stone types used in Ireland and also uniformity in methods to extract each specific type of bedrock. Factors determining the commercialisation of millstones are also addressed. This is followed by intensive field-based investigation focusing on millstone quarries in Waterford Harbour in the south-east of the country. Research questions concerning geology, transport, typology, what techniques were used to transform a 'rough-out' piece, and the role individual quarries and local people played in the overall industrialisation of millstone production are addressed.
The use of sarsen and puddingstone in England and Normandy since the Bronze Age is briefly reviewed (for sarsen), and described following fieldwork and museum research (for puddingstone). The rock ...sources of puddingstone/poudingue querns hand-mills are located and characterised, and the distribution of the products shown. The current distribution of Hertfordshire Puddingstone is shown, reflecting periglacial movement and human clearance. The production process is outlined for the main agency involved, the Romano-British puddingstone quern industry (AD 50–150). Sarsen-cutting, particularly in Wiltshire and Buckinghamshire between 1850 and 1939, provides a parallel case of clearance of boulders from the landscape. Industrial exploitation is shown to have radically altered the ‘natural’ distribution of silcretes in England and northern France.
Découverte à Montvendre dans la Drôme, dans un contexte antique, la meule de type Pompéien d’origine italique (basalte à leucite d’Orvieto, Ombrie), très usée, porte une inscription très lisible, ...inédite sur ce type de produits, P F M, suivi d’un O ou Q. Inscrite dans un contexte incontestablement rural, elle se rattache à une série bien représentée dans le Sud de la Narbonnaise en milieu urbain et rural, ainsi qu’à Vienne (38) et Lyon (69).
A Pompeian-type millstone of Italic origin (Orvieto leucite basalt, Umbria) has been found at Montvendre (Drôme), in an ancient context. Very worn, it has however a very legible, original inscription on this type of product : PFM, followed by an O or Q. Set in an undeniably rural context, it is part of a well represented serie in the southern Gallia Narbonensis, in urban and rural areas, as well as in Vienna (38) and Lyon (69).
Grâce aux fouilles réalisées au XVIIIe s., puis à l'archéologie préventive, on connaît une petite série d'établissements agricoles dans le territoire pompéien. Généralement réensevelies après leur ...découverte, ces villae nous sont connues de façon indirecte, à travers l'étude des rares notices et des documents d'archives. Fréquemment, la position topographique de chaque villa et leur organisation interne nous sont connues. Les espaces de préparation culinaire sont identifiés grâce aux aménagements construits et à des objets particuliers. En revanche, il est rare que nous disposions d'inventaires complets, qu'il s'agisse des objets céramiques ou des restes fauniques. Les études pluridisciplinaires associant analyses scientifiques des objets et des espaces sont presque inexistantes. De cette façon, la documentation et l'historiographie des cuisines des villae rusticae sont en tout point comparables avec les connaissances disponibles sur les cuisines urbaines de Pompéi. Cependant ces aménagements diffèrent radicalement. En étudiant ces espaces de préparation culinaire, on tentera de déterminer de quelle manière leur organisation dépend des besoins propres aux différents établissements agricoles. Thanks to 18th century excavations and to rescue archaeology a small series of agricultural establishments on the territory of Pompeii is well documented. These villae, generally reburied after excavation, are only known indirectly, through the study of a few notes and archive documents. Often the topographical position and internal organisation of each villa can be identified. Areas dedicated to the preparation of food can be recognised from their construction and particular objects. On the other hand, we rarely have available comprehensive inventories, be they of pottery or of faunal remains. Multidisciplinary studies associating scientific analyses of objects with spaces have almost never been conducted. This accounts for the fact that the documentation and historiography on the kitchens of villae rusticae are entirely comparable with the knowledge available for Pompeian urban kitchens. These types of kitchens, however, are quite different in nature. By studying these food preparation areas we shall try to determine how their arrangement depends on the specific needs of each separate agricultural establishment.
A millstone (MS) was introduced in the production of large-size few-layer-graphene oxide (FLGO) via true shear exfoliation in order to minimize fragmentation. The MS was constructed with two glass ...plates, where the top plate was designed to rotate against the stationary bottom plate, thereby generating true shear force. Mildly oxidized graphite (MOG) was used for MS exfoliation in order to obtain both good property and high yield. The rpm of rotation (10, 20, 30, 40, and 50), solution concentration (0.5, 1, and 2 mg/ml), and number of exfoliation (1, 2, and 3) were optimized by measuring the UV-vis absorption, and the effect of oxidation time (30, 60, and 90 min) was studied under the given optimum conditions. Next, the FLGO was isolated by centrifugation and characterized by TEM and AFM. The FLGO obtained was as large as ~ 10 μm in size, which was slightly smaller than the pristine graphite, suggesting a possibility of slight fragmentation. But it was still much larger than the FLGO obtained via sonication (< 1 μm), demonstrating successful MS exfoliation.
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