586 resultados para pneumatic conveying
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Comunicação apresentada no CYTEF 2016/VIII Congresso Ibérico | VI Congresso Ibero-Americano de Ciências e Técnicas do Frio, 3-6 maio 2016, Coimbra, Portugal
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This study focuses on the temperature field observed in boreholes drilled as part of interdisciplinary scientific campaign targeting the El'gygytgyn Crater Lake in NE Russia. Temperature data are available from two sites: the lake borehole 5011-1 located near the center of the lake reaching 400 m depth, and the land borehole 5011-3 at the rim of the lake, with a depth of 140 m. Constraints on permafrost depth and past climate changes are derived from numerical simulation of the thermal regime associated with the lake-related talik structure. The thermal properties of the subsurface needed for these simulations are based on laboratory measurements of representative cores from the quaternary sediments and the underlying impact-affected rock, complemented by further information from geophysical logs and data from published literature. The temperature observations in the lake borehole 5011-1 are dominated by thermal perturbations related to the drilling process, and thus only give reliable values for the lowermost value in the borehole. Undisturbed temperature data recorded over more than two years are available in the 140 m deep land-based borehole 5011-3. The analysis of these observations allows determination of not only the recent mean annual ground surface temperature, but also the ground surface temperature history, though with large uncertainties. Although the depth of this borehole is by far too insufficient for a complete reconstruction of past temperatures back to the Last Glacial Maximum, it still affects the thermal regime, and thus permafrost depth. This effect is constrained by numerical modeling: assuming that the lake borehole observations are hardly influenced by the past changes in surface air temperature, an estimate of steady-state conditions is possible, leading to a meaningful value of 14 ± 5 K for the post-glacial warming. The strong curvature of the temperature data in shallower depths around 60 m can be explained by a comparatively large amplitude of the Little Ice Age (up to 4 K), with low temperatures prevailing far into the 20th century. Other mechanisms, like varying porosity, may also have an influence on the temperature profile, however, our modeling studies imply a major contribution from recent climate changes.
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Mode of access: Internet.
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National Highway Safety Bureau, Washington, D.C.
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Transportation Systems Center, Cambridge, Mass.
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"First prize."
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Mode of access: Internet.
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Mode of access: Internet.
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Vols. 7-13 have added t.p.: Schlomann-Oldenbourgh illustrierte technische wörterbücher, unter mitwirkung hervorragender fachieute des in- und auslandes, hrsg. von Alfred Schlomann ... Müchen und Berlin, Druck und verlag von R. Oldenbourg; London, Constable & Co., etc.
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Book No. 125.
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"Essays of Dr. Franklin"--p. [136]-180. "We have selected a few of his lighter essays as a sequel to the biography; desirable, both as displaying somewhat of the character of their author, and conveying common sense maxims likely to be of much service to the young."--p. [136]. Includes verse.
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Includes index.
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A common assumption is that language is used for conveying factual information, but linguistic forms also serve a way to communicate pragmatic features, such as speakers’ intentions and mental state. This study describes and analyses two strategies for stance-taking in GhaPE, more specific the use of discourse particles and complement-taking predicates. Such grammatical resources have been identified in the literature to play important functions in signalling how the speaker evaluates and positions him/herself and the addressee with respect to objects of discourse. The analysis and discussion of forms is informed by Du Bois’ (2007) ‘stance triangle’, which has proved to be a useful analytical device for investigating stance from a dialogical perspective. GhaPE is at times anticipated as fairly simple both by scholars and in the community where it is spoken. This thesis is thus an attempt to display aspects of the richness of the language.
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Two different slug test field methods are conducted in wells completed in a Puget Lowland aquifer and are examined for systematic error resulting from water column displacement techniques. Slug tests using the standard slug rod and the pneumatic method were repeated on the same wells and hydraulic conductivity estimates were calculated according to Bouwer & Rice and Hvorslev before using a non-parametric statistical test for analysis. Practical considerations of performing the tests in real life settings are also considered in the method comparison. Statistical analysis indicates that the slug rod method results in up to 90% larger hydraulic conductivity values than the pneumatic method, with at least a 95% certainty that the error is method related. This confirms the existence of a slug-rod bias in a real world scenario which has previously been demonstrated by others in synthetic aquifers. In addition to more accurate values, the pneumatic method requires less field labor, less decontamination, and provides the ability to control the magnitudes of the initial displacement, making it the superior slug test procedure.
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The importance of sticky behaviour of amorphous food powders has been recognized over many decades in the food industry due to its influence on process and handling abilities and quality of the powders. This paper emphasizes the role of stickiness in the food powder industry as well as reviews the stickiness characterization techniques developed to date. This paper also attempts to correlate the stickiness behaviour of food powders to the instrumental analysis such as glass transition temperature. (C) 2004 Elsevier B.V All rights reserved.