940 resultados para petroleum industries
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A method using iodine has been developed for the stabilisation of low softening point (SP) pitch fibres that avoids air stabilisation in the production of carbon fibres (CF). The interaction between iodine and petroleum pitches has been studied by following the changes in the hydrogen content, aromatic or aliphatic, during the heat treatment of iodine-treated pitch fibres. Two low SP petroleum pitches were used and the iodine-treated pitch fibres were analysed by TGA, DSC, DRIFT, XPS and SEM. The results confirm that using this novel method pitches with low SP can be used to prepare CF with two advantages, compared with conventional methods. The stabilisation time is considerably reduced and treatments to increase the SP, usually required when low SP pitches are used to prepare CF, can be avoided.
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The paper provides interesting evidences that a low softening point isotropic petroleum pitch can be used as a good carbon precursor for the preparation of activated carbons. The activation is carried out by KOH and/or NaOH and the resulting activated carbons present well developed porosity. Such hydroxide activations can be done directly on the pristine petroleum pitch (P) or on the pitch that has been submitted to an air stabilisation followed by a N2 heat treatment (TAN). In general, KOH activation produces better results than NaOH, both in terms of porosity and yield, the results obtained for the activation of TAN being impressive because of the good porosity developments and high yields reached. The different treatments carried out over the petroleum pitch precursor clearly show that they significantly influence the extent of microporosity development. This is due to different changes occurring in the porous structure of the precursor as a function of the treatment carried out. The efficiency of the activation process increases as the mesophase content of the precursor decreases, as well as the mesophase formation during the activation process is avoided.
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En este artículo se presentan datos experimentales de resistencia a flexión y a compresión de morteros de cemento Portland con adición y sustitución de breas de petróleo y de alquitrán de carbón, que son subproductos de la industria del carbón o del petróleo. Los materiales estudiados son breas de alquitrán de carbón A (BACA) y B (BACB), y dos breas de petróleo (BPP) y (BPT). Los datos demuestran la viabilidad del uso de estas breas en la fabricación de morteros con menores contenidos de cemento, permitiendo diseñar un nuevo material sostenible con el medio ambiente y que contribuya a reducir el impacto ambiental de los materiales de construcción, hecho que permite abrir una nueva vía de valorización de estos subproductos.
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Although cultural industries can benefit from social networks in many ways, few Spanish studies examine the extent to which firms within this economic sector actually use such networks. This study's objective is to investigate the role of online social networks in Spanish cultural firms. The study begins with a literature review on cultural industries and social networks. Then the study proceeds to a Delphi analysis that draws upon experts' opinions. Results reveal a predominance of utilitarian uses over expressive ones, as well as an overriding use of proactive motivations rather than reactive ones within the context of cultural firms' use of social networks. The study confirms the profitability of these networks and the transfer of influence or power from providers to the consumers of cultural goods and services.
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This article reviews the evolution of the concept of culture industries, when neither industry nor culture themselves are today what they were at the time when the term was coined. It attempts to explain the dilution of the term into more nebulous terms (“leisure industries,” “entertainment industries” or “creative industries”) and suggests new challenges for the research on culture industries. What is at stake is no longer an application of a Fordist production to culture, a one-directional mass communication and a mediation by experts, but rather: (1) a cultural experience which is no longer clearly separated from other activities (leisure in general, consumption and even work); (2) the communicative explosion of all industrial production in a media environment, where industrialized symbolic products are mixed with culturalized industrial products; and (3) the empowerment of the recipient, which on one hand ignores the traditional experts and on the other leads to post-productive (recreational and even creative) cultural practices.
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by W. Jett Lauck and Edgar Sydenstricker.
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Includes bibliographical references.
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Includes bibliographical references.
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National Industrial Conference Board.
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This layer is a georeferenced raster image of the historic paper map entitled: Hafen-und Industrie-Anglagen im Osten der Stadt Frankfurt a. M., Tiefbau-Amt. Direktion des städt Hafen-Brücken-u. Kanalbaues. It was published by Rathaus Südabau in 1911. Scale 1:20,000. Covers Frankfurt am Main, Germany. Map in German.The image inside the map neatline is georeferenced to the surface of the earth and fit to the Deutsches Hauptdreiecksnetz (DHDN) 3-degree Gauss-Kruger Zone 3 coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as roads, railroads and stations, drainage, built-up areas and selected buildings, industry locations, ground cover, parks, and more. This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.
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This layer is a georeferenced raster image of the historic paper map entitled: Cleveland, sixth city : railroad and industrial map issued by the Cleveland Chamber of Commerce Transportation Committee; prepared under the direction of D.F. Hurd, traffic commissioner. It was published by Cleveland Chamber of Commerce Transportation Committee in 1913. Scale [1:158,400]. The image inside the map neatline is georeferenced to the surface of the earth and fit to Ohio North State Plane NAD 1983 coordinate system (in Feet) (Fipszone 3401). All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as roads, railroads, freight, passenger, and dock line railway stations, street car lines, drainage, industry locations (e.g. mills, factories, mines, etc.), docks, city boundaries, and more. Includes index to industries.This layer is part of a selection of digitally scanned and georeferenced historic maps of New England from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of regions, originators, ground condition dates, scales, and map purposes.