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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

A Study on the Bevel Gear with Circular-Arc Tooth Profiles

Kuo, Hsiu-Ming 23 July 2001 (has links)
Nowadays, the bevel gears are widely applied in the industry for the intersected-axial transmission system. But the applications of the bevel gears are mostly limited to the usage of involute bevel gears. In this thesis, the bevel gear with circular-arc tooth profiles is derived by using general theorem of conjugate surfaces, coordinate transformation, constrained meshing equation, and spherical trigonometry. According to the bevel gears with circular-arc tooth profile derived above, the analyses and discussions of the interference are proposed. The interference situation is detected by applying the phase lead-lag concept while circular-arc curve is moving on the spherical cross-section. Furthermore, the ideal conditions to avoid occurrence of interference are proposed. Design charts for the maximum values of tooth profile angle are also constructed as a reference for designers. The 3D solid models of the bevel gear with circular-arc tooth profiles are constructed by using the computer software (Pro/E). Finally, the transmission ability is verified through the computer animation using CAE software (Visual Nastran). It is believed that the mathematical models and design method developed in the thesis will provide a useful foundation for the further studies.
112

Déterminisme nutritionnel et génétique de la teneur en lipides musculaires chez la truite arc-en-ciel (Oncorhynchus mykiss) étude par analyse de l'expression de gènes candidats, du protéome et du transcriptome du foie et du muscle /

Kolditz, Catherine-Inès Médale, Françoise. Lefèvre, Florence. January 2008 (has links) (PDF)
Thèse de doctorat : Sciences de la vie et de la santé. Sciences des aliments et nutrition : Bordeaux 1 : 2008. / Titre provenant de l'écran-titre.
113

Metalinių purkštųjų dangų struktūros ir savybių priklausomybės nuo technologinių parametrų tyrimas / Research of dependence of structure and properties of thermal sprayed metallic coatings upon technological parameters

Gedzevičius, Irmantas 16 September 2005 (has links)
The algorithm of arc spraying process simulation was created, which allow to make prognosis of arc spraying jet configuration and flying particles parameters. This scientific research shows the dependence between the arc spraying technological parameters and mechanical and physical properties of the obtained coatings. It was established, how by change of the spraying parameters the coatings with the best exploiting parameters can by received. The performed research shows the influence of the kind of the sprayed material on morphology of the formed jet particles and on technical and structural characteristics of the formed coatings. On basis of obtained results made suggestions how to improve the creation of thermal spraying coatings making new products or making restoration.
114

Cathode erosion in magnetically rotated arces

Szente, Roberto Nunes. January 1986 (has links)
No description available.
115

Volcanostratigraphic framework and magmatic evolution of the Oyu Tolgoi porphyry Cu-Au district, South Mongolia

Wainwright, Alan John 05 1900 (has links)
The super-giant Oyu Tolgoi porphyry copper-gold deposits in the South Gobi desert, Mongolia, consist of multiple discrete porphyry centers aligned within a north-northeast trending, >6.5 km long, arc-transverse mineralized corridor. The porphyries are linked to a tectono-magmatic event at ~372 Ma within a Devonian to Carboniferous volcanic arc, and U-Pb (zircon) geochronology records magmatic activity from ~390 Ma to ~320 Ma. The Oyu Tolgoi district underwent at least three discrete periods of syn- to post-mineral shortening and there is evidence for at least three unconformities within the Paleozoic sequence. Although the deposits were formed in an active orogenic environment characterized by rapid uplift, their preservation is a reflection of climactic effects as well insulation from erosion by rapid burial under mass-wasted and pyroclastic material in the volcaniclastic apron of late-mineral dacitic volcanoes. The porphyry copper-gold deposits are spatially and temporally related to medium- to high-K calc-alkaline quartz monzodiorite (~372 Ma) and granodiorite (~366 Ma) intrusive phases that comprise the Late Devonian Oyu Tolgoi Igneous Complex (OTIC). Adakite-like wholerock compositions as well as zircon grains with high CeN/CeN*, EuN/EuN* and Yb/Gd in the sample populations from syn- and late-mineral porphyry intrusions are different from younger intrusions that are not related to porphyry Cu-Au deposit formation. Moreover, mixed zircon populations within OTIC intrusions indicate that efficient assimilation of material from different host rocks by a convecting magma chamber occurred. Mafic to intermediate volcanic units evolved from tholeiitic to calc-alkaline compositions, which is interpreted to be a reflection of marine arc maturation and thickening. Felsic rock suites are dominantly high-K calc-alkaline, regardless of age. Nd-isotopic geochemistry from all suites is consistent with magma derivation from depleted mantle in an intra-oceanic volcanic arc and lead isotopic compositions indicate that the sulfides in the porphyry Cu-Au deposits are genetically linked to the Late Devonian magmas. Magma mixing, adakite-like magmatism and rapid uplift and erosion in a juvenile marine arc setting differentiate the ore-stage geologic environment at Oyu Tolgoi from other settings in active and fossil volcanic arcs.
116

Metalinių purkštųjų dangų struktūros ir savybių priklausomybės nuo technologinių parametrų tyrimas / Research of dependence of structure and properties of thermal sprayed metallic coatings upon technological parameters

Gedzevičius, Irmantas 07 September 2005 (has links)
The algorithm of arc spraying process simulation was created, which allow to make prognosis of arc spraying jet configuration and flying particles parameters. This scientific research shows the dependence between the arc spraying technological parameters and mechanical and physical properties of the obtained coatings. It was established, how by change of the spraying parameters the coatings with the best exploiting parameters can by received. The performed research shows the influence of the kind of the sprayed material on morphology of the formed jet particles and on technical and structural characteristics of the formed coatings. On basis of obtained results made suggestions how to improve the creation of thermal spraying coatings making new products or making restoration.
117

Theoretical and experimental study of wave forms of transformer supplying mercury-arc rectifier

Brown, Hugh Austin 12 1900 (has links)
No description available.
118

Plasma torch interaction with a melting substrate

Hill, S. D. 08 1900 (has links)
No description available.
119

Characteristics of a thermal plasma containing zirconium tetrachloride : a thesis

Kyriacou, Andreas. January 1982 (has links)
No description available.
120

The production of ultrafine silica particles through a transferred arc plasma process /

Gans, Ira. January 1986 (has links)
No description available.

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