56 resultados para Flake
Interaction of heat-moisture conditions and physical properties in oat processing: II. Flake quality
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Product quality is an important determinant of consumer acceptance. Consistent oat flake properties are thus necessary in the mill as well as in the marketplace. The effects of kilning and tempering conditions (30, 60 or 90 min at 80, 95 or 110 degrees C) on flake peroxidase activity, size, thickness, strength and water absorption were therefore determined. After kilning, some peroxidase activity remained but steaming and tempering effectively destroyed the activity of these enzymes. Thus the supposed protective effect of kilning or groat durability was not confirmed. Kilning resulted in an increase in flake specific weight, but no other significant effect on flake quality was observed. Tempering time and temperature interacted significantly to produce complex effects on flake specific weight, thickness and water absorption. Flake thickness and specific weight were significantly correlated (r = 0.808, n = 54). Longer tempering times resulted in an increased fines' fraction, from 1.45% at 30 min to 1.75% at 90 min. It is concluded that whilst kilning has little effect on flake quality, the heat treatment immediately prior to flaking, can be used to adjust flake quality independently of flake thickness.
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The ability of the one-dimensional lake model FLake to represent the mixolimnion temperatures for tropical conditions was tested for three locations in East Africa: Lake Kivu and Lake Tanganyika's northern and southern basins. Meteorological observations from surrounding automatic weather stations were corrected and used to drive FLake, whereas a comprehensive set of water temperature profiles served to evaluate the model at each site. Careful forcing data correction and model configuration made it possible to reproduce the observed mixed layer seasonality at Lake Kivu and Lake Tanganyika (northern and southern basins), with correct representation of both the mixed layer depth and water temperatures. At Lake Kivu, mixolimnion temperatures predicted by FLake were found to be sensitive both to minimal variations in the external parameters and to small changes in the meteorological driving data, in particular wind velocity. In each case, small modifications may lead to a regime switch, from the correctly represented seasonal mixed layer deepening to either completely mixed or permanently stratified conditions from similar to 10 m downwards. In contrast, model temperatures were found to be robust close to the surface, with acceptable predictions of near-surface water temperatures even when the seasonal mixing regime is not reproduced. FLake can thus be a suitable tool to parameterise tropical lake water surface temperatures within atmospheric prediction models. Finally, FLake was used to attribute the seasonal mixing cycle at Lake Kivu to variations in the near-surface meteorological conditions. It was found that the annual mixing down to 60m during the main dry season is primarily due to enhanced lake evaporation and secondarily to the decreased incoming long wave radiation, both causing a significant heat loss from the lake surface and associated mixolimnion cooling.
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"January 5, 1955."
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Tese de Doutoramento em Ciências da Saúde
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[s.c.]
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One presents a clinical case, of a man of approximately 40 years, presenting like clinical stains of variable coloration, of brown aspect and hipocrómicas, that on having been scraped flake off easily. After his diagnosis of ptiriasis vesicolor, it yields to antifúngicos topics. We will analyze this one I marry, and we will see his etiology, clinic dignóstico and treatment.
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Soil consolidation and erosion caused by roadway runoff have exposed the upper portions of steel piles at the abutments of numerous bridges, leaving them susceptible to accelerated corrosion rates due to the abundance of moisture, oxygen, and chlorides at these locations. This problem is compounded by the relative inaccessibility of abutment piles for close-up inspection and repair. The objective of this study was to provide bridge owners with recommendations for effective methods of addressing corrosion of steel abutment piles in existing and future bridges A review of available literature on the performance and protection of steel piles exposed to a variety of environments was performed. Eight potential coating systems for use in protecting existing and/or new piles were selected and subjected to accelerated corrosion conditions in the laboratory. Two surface preparation methods were evaluated in the field and three coating systems were installed on three piles at an existing bridge where abutment piles had been exposed by erosion. In addition, a passive cathodic protection (CP) system using sacrificial zinc anodes was tested in the laboratory. Several trial flowable mortar mixes were evaluated for use in conjunction with the CP system. For existing abutment piles, application of a protective coating system is a promising method of mitigating corrosion. Based on its excellent performance in accelerated corrosion conditions in the laboratory on steel test specimens with SSPC-SP3, -SP6, and -SP10 surface preparations, glass flake polyester is recommended for use on existing piles. An alternative is epoxy over organic zinc rich primer. Surface preparation of existing piles should include abrasive blast cleaning to SSPC-SP6. Although additional field testing is needed, based on the results of the laboratory testing, a passive CP system could provide an effective means of protecting piles in existing bridges when combined with a pumped mortar used to fill voids between the abutment footing and soil. The addition of a corrosion inhibitor to the mortar appears to be beneficial. For new construction, shop application of thermally sprayed aluminum or glass flake polyester to the upper portion of the piles is recommended.
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Työssä tutkittiin uuden ShortFlowÔ-konseptin eri osa-alueiden toimivuutta paperikoneen lyhytkierrossa. Prosessin sekoituspumppuna perinteinen keskipakopumppu korvataan potkuri-pumpulla, joten työssä selvitettiin uudentyyppisen pumpun kavitointirajat, säädettävyys ja sen soveltuminen suunniteltuun tehtävään ja toiminta-alueeseen. Prosessiin kuuluu myös uudentyyppinen viirakaivo, josta selvitettiin sen kyky poistaa ilmaa ja virtauskäyttäytyminen kaivossa. Hienopaperikoneen osalta kartoitettiin prosessiin liittyviä riskejä ja ShortFlowÔ-lyhytkiertoprosessin kannattavuutta investointina. Työn kirjallisessa osassa on käsitelty lyhytkiertoa eri osa-alueittain. Aluksi on lyhytkierron yleisempi tarkastelu, jossa on selvitetty lajittelua, ilmanpoistoa ja pumppauksia. Erityisempää huomiota on kiinnitetty ShortFlowÔ-lyhytkiertoprosessiin liittyviin erityispiirteisiin joita ovat sakeamassalajittelu, täyteaineet paperitehtaalla, hylky ja virtausten sekoittuminen. Sekoituspumpun osalta on käsitelty myös kavitointia hieman tarkemmin. Työn kokeellisessa osassa suunniteltiin prosessin koelaitteisto, joka myös koeajettiin. Potkuripumpun koeajossa määritettiin potkuripumpun toiminta-alue ja säädettävyys. Pumpun todettiin sekoittavan ja ilman vaikutus potkuripumpun ominaisuuksiin todettiin merkityksettömäksi pumpun toiminta-alueella. Viirakaivon koeajossa selvisi, että viirakaivo poistaa ilmaa suunnittelualueella ja kaivolle löytyi muoto, jossa virtauskäyttäytyminen viirakaivossa eri laskeutumisnopeuksilla on mahdollisimman häiriötöntä. Hienopaperikoneen osalta riskien kartoituksessa selvisi, ettei täyteaine aiheuta ongelmia ja että päällystelaattaa sisältävä hylky on lajiteltava ennen lyhytkiertoa. ShortFlowÔ-lyhytkiertoprosessi oli edullisin sekä käyttö- että investointikustannuksiltaan.
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Iron(III) acetate was synthesized by the reflux method using iron enriched in the 57Fe isotope and the compound processed by freeze-drying. The as-synthesized and freeze-dried acetates were characterized regarding their structural, thermal, vibrational and hyperfine properties. Similar diffractometric and spectroscopic results were found for both materials and also for an industrial acetate made with natural iron. However, the microstructures differed: the as-synthesized compound showed flake morphology with micrometric dimensions, whereas the freeze-dried showed flake morphology with sub-micrometric dimensions. The activation energies for thermal decomposition, calculated from the exothermic events occurring in differential scanning calorimetry measurements, were 100.9 kJ/mol (as-synthesized) and 114.7 kJ/mol (freeze-dried).
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Le site de la carrière du mont Royal (BjFj-97), découvert en 1993 par Yvon Codère et inventorié en 1997 par l’équipe d’Ethnoscop Inc., constitue une énigme archéologique intéressante pour quiconque s’intéresse à la préhistoire de l’île de Montréal et de sa région adjacente. Lors des activités archéologiques de 1997, quelques idées furent émises quant à son affiliation chronologique et sa nature, suggérant une occupation remontant à l’Archaïque terminal (4000 à 3000 AA) orientée vers l’extraction et la transformation de la cornéenne, une pierre métamorphique résultant de la transformation du substrat rocheux en place suite à des intrusions magmatiques lors du Crétacé qui ont créé les Montérégiennes. Le matériel, comprenant plus de 10 000 déchets de taille et un peu plus de 70 artéfacts divers, ne fît pas l’objet d’analyses poussées hormis la datation approximative du site par un examen sommaire des pointes de projectile. Ce mémoire reprend les données de 1997 et apporte une perspective nouvelle au site en décrivant morphologiquement et technologiquement le débitage de la pierre de façon à comprendre la chaîne opératoire de la cornéenne, une matière peu étudiée, mais fort commune au Québec méridional, appréhender les possibilités de la matière et aborder les questions de datation. L’ensemble du matériel lithique fît l’objet d’une analyse lithique poussée axée sur le débitage et les produits finis et propose la prépondérance de la taille bifaciale, ponctuée par un débitage sur éclat conséquent. L’ensemble des étapes de la chaîne opératoire est présent sur le site de la carrière du mont Royal. La cornéenne est une matière difficile à tailler en raison de son imprévisibilité, liée à la structure même de la matière, menant à un fort taux d’échecs lors de l’élaboration des outils. La datation de l’occupation principale du site pointe vers l’Archaïque terminal, mais le caractère équivoque des diverses classes d’objets rend difficile sa définition absolue, faute d’objets parfaitement diagnostiques. Le site BjFj-97 ressemble grandement à un site homologue en Nouvelle-Angleterre où la cornéenne fût travaillée suivant le même schéma opératoire, suggérant un apparentement culturel possible. La cornéenne abonde et domine dans les assemblages archéologiques de la région montréalaise, substituant ainsi des matières de meilleure qualité absentes régionalement. Leurs correspondances chronologiques transcendent celles établies lors de l’analyse du matériel de la carrière et montrent un étalement chronologiquement plus étendu, de l’Archaïque laurentien au Sylvicole supérieur. La cornéenne se retrouve habituellement sous forme d’outils bifaciaux fonctionnels (bifaces, couteaux et pointes de projectile) de piètre facture et d’outils sur éclats (grattoirs et racloirs) rudimentaires, suggérant une signification strictement utilitaire, le propre des matières de basse qualité. Les modes d’extraction de la cornéenne restent inconnus sur le mont Royal. Le mont Royal est plus qu’un vulgaire point défensif, il constitue la base de la subsistance des populations préhistoriques de jadis où se trouvent les matériaux nécessaires à la taille d’outils de prédation liés à un mode de vie mobile où domine la chasse.
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In den bundesweit rund 670 anerkannten Werkstätten für behinderte Menschen (WfbM) arbeiten aktuell über 290 000 Menschen mit Behinderung. Rund ein Viertel dieser Einrichtungen bieten auch landwirtschaftliche oder gartenbauliche Arbeitsplätze (`Grüne WfbM´). Die UN-Behindertenrechtskonvention fordert u. a. eine inklusive Teilhabe der Menschen mit Behinderung am Arbeitsleben in Form von Zugangsmöglichkeiten zu sozialversicherungspflichtiger Beschäftigung auf dem allgemeinen Arbeitsmarkt. Gleichzeitig können arbeitswirtschaftlich immer mehr landwirtschaftliche Betriebe aufgrund wachsender Betriebsgrößen nicht mehr allein durch die Unternehmerfamilie geführt werden. Neben der Zuhilfenahme von Dienstleistungsanbietern ist die Suche nach Fremdarbeitskräften zwangsläufig. Neben dem Bedarf an qualifiziertem Fachpersonal werden auch Arbeitskräfte für einfachere, tägliche Routinearbeiten gesucht. Die vorliegende Arbeit begleitet wissenschaftlich ein vom Bundesministerium für Ernährung, Landwirtschaft und Verbraucherschutz gefördertes bundesweites Modellvorhaben zur Vernetzung `Grüner WfbM´ mit landwirtschaftlichen Betrieben. Forschungsleitende Fragestellungen sind die betrieblichen Interessen und Voraussetzungen aus Sicht der landwirtschaftlichen Betriebe für die Beschäftigung von Menschen mit Behinderung sowie für bilaterale Kooperationen mit diesen Einrichtungen. Anhand von 44 Betriebsinterviews und unter Anwendung einer qualitativen, rechnerbasierten Fallstudienanalyse zeigen die Ergebnisse eine Vielzahl von Möglichkeiten wirtschaftlich tragfähiger Beschäftigung behinderter Menschen auch in Kernproduktionsprozessen. Unabdingbar dafür sind angepasste Sozialtugenden und ausreichende Arbeitsmotivation auf Arbeitnehmerseite sowie eine offen-innovative und sozial geprägte Grundeinstellung auf Betriebsleitungsseite. Betriebe wünschen sich dauerhafte und verlässliche Arbeitsverhältnisse. Praktika oder gar Experimente kommen für sie eher nicht in Frage. Weniger als 10% aller `Grünen WfbM´ kooperieren bilateral mit umliegenden Betrieben. Dort wo keine Kontakte bestehen, sind Vorbehalte seitens der Landwirte hinsichtlich Wettbewerbsverzerrungen durch vermeintliche Sozialsubventionierung bzw. im Wettbewerb um Ressourcen (z.B. Land) gegenüber den Einrichtungen anzutreffen. Kooperationen fördern gegenseitiges Verständnis und sind so auch idealer `Türöffner´ für Beschäftigungsverhältnisse.
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The radar scattering properties of realistic aggregate snowflakes have been calculated using the Rayleigh-Gans theory. We find that the effect of the snowflake geometry on the scattering may be described in terms of a single universal function, which depends only on the overall shape of the aggregate and not the geometry or size of the pristine ice crystals which compose the flake. This function is well approximated by a simple analytic expression at small sizes; for larger snowflakes we fit a curve to Our numerical data. We then demonstrate how this allows a characteristic snowflake radius to be derived from dual wavelength radar measurements without knowledge of the pristine crystal size or habit, while at the same time showing that this detail is crucial to using such data to estimate ice water content. We also show that the 'effective radius'. characterizing the ratio of particle volume to projected area, cannot be inferred from dual wavelength radar data for aggregates. Finally, we consider the errors involved in approximating snowflakes by 'air-ice spheres', and show that for small enough aggregates the predicted dual wavelength ratio typically agrees to within a few percent, provided some care is taken in choosing the radius of the sphere and the dielectric constant of the air-ice mixture; at larger sizes the radar becomes more sensitive to particle shape, and the errors associated with the sphere model are found to increase accordingly.