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Academic literature on the topic 'Melt source'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Melt source"

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Maaløe, S. "Melt dynamics of a layered mantle plume source." Contributions to Mineralogy and Petrology 133, no. 1-2 (October 1998): 83–95. http://dx.doi.org/10.1007/s004100050439.

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Moallemi, M. K., and R. Viskanta. "Melting Around a Migrating Heat Source." Journal of Heat Transfer 107, no. 2 (May 1, 1985): 451–58. http://dx.doi.org/10.1115/1.3247436.

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The problem of melting around a moving heat source arises in many different situations such as nuclear reactor technology (i.e., “self-burial” process of nuclear waste materials and reactor core “melt-down”), process metallurgy, and geophysics. Experiments were undertaken with a horizontal cylindrical heat source that melted its way through a phase-change material (n-octadecane) under its own weight. The heat source velocity and solid-liquid interface motion for a constant surface temperature source were measured. Effects of heat source density and surface temperature as well as the effects of the initial subcooling of the solid were investigated and are reported. The flow structure in the melt was visualized using a dye. Timewise variation of temperature distribution in the solid and the melt were also measured and are discussed. Results for the heat source migration velocity and the volume of the material melted are correlated in terms of the relevant problem parameters.
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Searle, M. P., J. M. Cottle, M. J. Streule, and D. J. Waters. "Crustal melt granites and migmatites along the Himalaya: melt source, segregation, transport and granite emplacement mechanisms." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 100, no. 1-2 (March 2009): 219–33. http://dx.doi.org/10.1017/s175569100901617x.

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ABSTRACTIndia–Asia collision resulted in crustal thickening and shortening, metamorphism and partial melting along the 2200 km-long Himalayan range. In the core of the Greater Himalaya, widespread in situ partial melting in sillimanite+K-feldspar gneisses resulted in formation of migmatites and Ms+Bt+Grt+Tur±Crd±Sil leucogranites, mainly by muscovite dehydration melting. Melting occurred at shallow depths (4–6 kbar; 15–20 km depth) in the middle crust, but not in the lower crust. 87Sr/86Sr ratios of leucogranites are very high (0·74–0·79) and heterogeneous, indicating a 100 crustal protolith. Melts were sourced from fertile muscovite-bearing pelites and quartzo-feldspathic gneisses of the Neo-Proterozoic Haimanta–Cheka Formations. Melting was induced through a combination of thermal relaxation due to crustal thickening and from high internal heat production rates within the Proterozoic source rocks in the middle crust. Himalayan granites have highly radiogenic Pb isotopes and extremely high uranium concentrations. Little or no heat was derived either from the mantle or from shear heating along thrust faults. Mid-crustal melting triggered southward ductile extrusion (channel flow) of a mid-crustal layer bounded by a crustal-scale thrust fault and shear zone (Main Central Thrust; MCT) along the base, and a low-angle ductile shear zone and normal fault (South Tibetan Detachment; STD) along the top. Multi-system thermochronology (U–Pb, Sm–Nd, 40Ar–39Ar and fission track dating) show that partial melting spanned ̃24–15 Ma and triggered mid-crustal flow between the simultaneously active shear zones of the MCT and STD. Granite melting was restricted in both time (Early Miocene) and space (middle crust) along the entire length of the Himalaya. Melts were channelled up via hydraulic fracturing into sheeted sill complexes from the underthrust Indian plate source beneath southern Tibet, and intruded for up to 100 km parallel to the foliation in the host sillimanite gneisses. Crystallisation of the leucogranites was immediately followed by rapid exhumation, cooling and enhanced erosion during the Early–Middle Miocene.
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Guo, Kai, Yunping Ji, Yiming Li, Xueliang Kang, Huiyi Bai, and Huiping Ren. "Numerical Simulation of Temperature Field and Melt Pool Characteristics of CP-Ti Manufactured by Laser Powder Bed Fusion." Metals 13, no. 1 (December 20, 2022): 11. http://dx.doi.org/10.3390/met13010011.

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A coupled heat source model that combined a Gauss surface heat source with a Gauss cylindrical volumetric heat source was introduced to simulate temperature field distribution and melt pool characteristics using a finite element simulation (FEM) method for the deep and narrow melt pools formed in laser powder bed fusion (L-PBF) aiming at commercial pure titanium (CP-Ti). For comparison, the same simulations using the Gauss surface heat source model and the double ellipsoid heat source model were also performed. The simulated melt pool geometries using the coupled heat source model match well with the measurements, with an average error of 1% for the melt pool depth and 7% for the width. Based on the single-track experimental results, it was found by comparing the simulated results from the three heat source models that the coupled heat source model had better accuracy than the other two. Then, the temperature field and the melt pool geometries of CP-Ti fabricated at different laser power levels from 300 W to 500 W and scanning speeds from 600 mm/s to 4000 mm/s were simulated. According to the simulated maximum temperature and geometries of the melt pool, a suitable process parameters map for CP-Ti was obtained. The reported experimental results agree well with the simulated map. The coupled heat source model is more accurate and applicable for the deep and narrow melt pools formed during L-PBF.
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Knapp, J. A., L. R. Thompson, and G. J. Collins. "The role of radiation in melt stability in zone-melt recrystallization of SOI." Journal of Materials Research 5, no. 5 (May 1990): 998–1002. http://dx.doi.org/10.1557/jmr.1990.0998.

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Under circumstances in Zone-Melt-Recrystallization (ZMR) of Si-on-Insulator (SOI) structures where radiative heat loss is significant, the ∼50% decrease in emissivity when Si melts destabilizes the Si molten zone. We have demonstrated this both experimentally using a slowly scanned e-beam line source and numerically with a finite-element computational simulation. The resulting instability narrows the process window and tightens requirements on beam control and background heating uniformity, both for e-beam ZMR systems and optically-coupled systems such as a graphite strip heater.
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Wieser, Penny, Maurizio Petrelli, Jordan Lubbers, Eric Wieser, Sinan Ozaydin, Adam Kent, and Christy Till. "Thermobar: An open-source Python3 tool for thermobarometry and hygrometry." Volcanica 5, no. 2 (November 9, 2022): 349–84. http://dx.doi.org/10.30909/vol.05.02.349384.

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We present Thermobar, a new open-source Python3 package for calculating pressures, temperatures, and melt compositions from mineral and mineral-melt equilibrium. Thermobar allows users to perform calculations with >100 popular parametrizations involving liquid, olivine-liquid, olivine-spinel, pyroxene only, pyroxene-liquid, two pyroxene, feldspar-liquid, two feldspar, amphibole only, amphibole-liquid, and garnet equilibria. Thermobar is the first open-source tool which can match up all possible pairs of phases from a given region, and apply various equilibrium tests to identify pairs from which to calculate pressures and temperatures (e.g. pyroxene-liquid, two pyroxene, feldspar-liquid, two feldspar, amphibole-liquid). Thermobar also contains functions allowing users to propagate analytical errors using Monte-Carlo methods, convert pressures to depths using different crustal density profiles, plot mineral classification and mineral-melt equilibrium diagrams, calculate liquid viscosities, and convert between oxygen fugacity values, buffer positions and Fe speciation in a silicate melt. Thermobar can be downloaded using pip and extensive documentation is available at https://thermobar.readthedocs.io/.
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Maaløe, S. "Extraction of melt from veined mantle source regions during eruptions." Journal of Volcanology and Geothermal Research 147, no. 3-4 (October 2005): 377–90. http://dx.doi.org/10.1016/j.jvolgeores.2005.04.016.

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Diener, Johann F. A., Richard W. White, and Timothy J. M. Hudson. "Melt production, redistribution and accumulation in mid-crustal source rocks, with implications for crustal-scale melt transfer." Lithos 200-201 (July 2014): 212–25. http://dx.doi.org/10.1016/j.lithos.2014.04.021.

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Kirdyashkin, A. A., A. G. Kirdyashkin, V. E. Distanov, and I. N. Gladkov. "ON HEAT SOURCE IN SUBDUCTION ZONE." Geodynamics & Tectonophysics 12, no. 3 (September 17, 2021): 471–84. http://dx.doi.org/10.5800/gt-2021-12-3-0534.

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The subduction of an oceanic plate is studied as the motion of a high-viscosity Newtonian fluid. The subducting plate spreads along the 670-km depth boundary under the influence of oppositely directed horizontal forces. These forces are due to oppositely directed horizontal temperature gradients. We consider the flow structure and heat transfer in the layer that includes both the oceanic lithosphere and the crust and moves underneath a continent. The heat flow is estimated at the contact between the subducting plate and the surrounding mantle in the continental limb of the subduction zone. Our study results show that the crustal layer of the subducting plate can melt and a thermochemical plume can form at the 670-km boundary. Our model of a thermochemical plume in the subduction zone shows the following: (1) formation of a plume conduit in the crustal layer of the subducting plate; (2) formation of a primary magmatic chamber in the area wherein the melting rate equals the rate of subduction; (3) origination of a vertical plume conduit from the primary chamber melting through the continent; (4) plume eruption through the crustal layer to the surface, i.e. formation of a volcano. Our experiments are aimed to model the plume conduit melting in an inclined flat layer above a local heat source. The melt flow structure in the plume conduit is described. Laboratory modeling have revealed that the mechanisms of melt eruption from the plume conduit differ depending on whether a gas cushion is present or absent at the plume roof.
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Ayoola, W. A., W. J. Suder, and S. W. Williams. "Comparison of Theoretical Disc and Point Source Profiles with Actual-Melt Source Profile in Conduction Welding." Nigerian Journal of Technological Development 19, no. 3 (September 23, 2022): 260–65. http://dx.doi.org/10.4314/njtd.v19i3.8.

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Prediction of fusion zone in numerical modelling of welds using a modified heat transfer model requires experimental results for validation. Primarily, the modified heat transfer models are developed from the point and disc source heat models which can be assumed to be a semi-circle or spherical shape. In this study, a simple relationship between melt areas, the depth of penetration and weld width was proposed for point and disc source profiles to represent the actual weld profile. The results obtained for focused and defocused laser beams indicate that the actual weld profile is closer to a point source than the disc source. The transition between the conduction and keyhole regimes was achieved when the actual weld depth of penetration is below that of the point source.
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Dissertations / Theses on the topic "Melt source"

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Gomez-Ulla, Rubira Alejandra. "Historical eruptions of Lanzarote, Canary Islands : Inference of magma source and melt generation from olivine and its melt inclusions." Thesis, Université Clermont Auvergne‎ (2017-2020), 2018. http://www.theses.fr/2018CLFAC023.

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L’étude des basaltes des îles océaniques (OIB) révèle la complexité du manteau terrestre, dont la composition chimique est hautement variable. Décrypter l’implication des lithologies des roches sources et des processus à l’origine des OIB est complexe car les magmas sont transformés lors de leur ascension jusqu’à la surface. Ceci est particulièrement critique dans le cas des îles Canaries, où la lithosphère est considérée comme particulièrement épaisse (>110 km Fullea et al., 2015). Afin de mieux contraindre la composition chimique des magmas primitifs et les lithologies mantelliques plausiblement impliquées, deux éruptions historiques de l’île de Lanzarote, les éruptions de Timanfaya (1730-1736) et celles de 1824, ont été étudiées. En effet, ces deux éruptions offrent une opportunité unique d’étudier les mécanismes de génération des magmas et leurs compositions dans un contexte où le manteau est hétérogène. L’éruption de historique de Timanfaya (1730-1736) a émis des magmas qui ont évolué de basanites à basaltes alcalins, pour atteindre des compositions tholeitiques à la fin de l’éruption. La dernière éruption de l’île, en 1824, a produit des basanites extrêmement riches en volatils. L’hétérogénéité du manteau est démontrée à l’extrême à Lanzarote où une seule éruption présente une variation de compositions chimiques équivalente à la diversité de celles des OIB dans le monde. L’extrême hétérogénéité est systématique pour les compositions des roches totales et des téphras à l’échelle d’une éruption, mais est encore amplifiée à l’échelle du minéral et des inclusions magmatiques contenus dans un même échantillon de téphra.Les concentrations des éléments traces et leurs rapports dans l’olivine (e.g. Ni, Mn et Ca) sont de précieux marqueurs des lithologies mantelliques à l’origine des magmas. En effet, les rapports Ni x (FeO/MgO), corrigé du fractionnement, et Fe/Mn sont des indicateurs de lithologies avec ou sans olivines. Il est considéré qu’ils peuvent montrer, dans la plupart des cas, l’ajout d’un liquide magmatique dérivé d’une pyroxénite dans les magmas primaires. La mesure des compositions des éléments traces des olivines des éruptions de 1730-1736 et de 1824 montrent les implications variables de plusieurs lithologies mantelliques au cours du temps. Lors de la fusion d’une lithologie ne contenant pas d’olivines, comme la pyroxénite, de hautes teneurs en Ni et de faibles teneurs en Mn et Ca sont attendues. Les basanites de Lanzarote présentent les plus grandes variations géochimiques, couvrant le champ compositionnel des olivines des MORB et des OIB du monde entier, tandis que les produits plus tardifs, c’est-à-dire les basaltes alcalins et les tholéites, ont des teneurs typiques de liquides magmatiques dérivés de pyroxénites. Les teneurs en forstérite (Fo) des olivines diminuent systématiquement avec le temps durant l’éruption de 1730-1736 et la proportion de liquide primaire saturé en silice augmente dans les mélanges de magmas primitifs avec le temps. A la fin de l’éruption, les magmas tholéitiques cristallisent des olivines dont la teneur en Fo est faible, alors que les concentrations en Mn et Ca augmentent simultanément avec le rapport Ca/Al pour des rapports Fe/Mn et Ni x (FeO/MgO) relativement constants. Ces observations sont expliquées par une augmentation de la fusion par décompression à température légèrement plus faible. D’autre part, les basanites de l’éruption de 1824 possèdent les olivines ayant les teneurs en Fo les plus élevées, et des teneurs en éléments traces dépassant la variabilité des basanites de l’éruption de Timanfaya. Le fait que les basanites de Lanzarote contiennent des olivines dont les compositions en éléments traces recouvrant le champ des MORB et des liquides pyroxènitiques est expliqué par la fusion d’une source contenant des lithologies hétérogènes, induite par un flux de CO2, générant ainsi des magmas aux compositions diverses. (...)
The study of oceanic island basalts (OIB) reveals the complexity of the mantle, which composition is highly variable. Deciphering the source lithologies and processes involved in the OIB formation is challenging since the magmas are transformed on their way to the surface. This is especially critical at Canary Islands where the lithosphere is thought to be remarkably thick (>110 km Fullea et al., 2015). In order to better constrain the composition of primitive magmas and the plausible mantle lithologies involved, two historical eruptions recorded at Lanzarote island, Timanfaya 1730-1736 and 1824 eruptions have been investigated. Indeed, these two eruptions offer a unique opportunity to investigate the mechanisms of magma generation and composition in the context of mantle heterogeneity. The Timanfaya, 1730-1736 historical eruption emitted magmas that evolved from basanites through alkali basalts, finally reaching tholeiitic compositions at the end of the eruption. In 1824 the last eruption on the island produced extremely volatile-rich basanite. The heterogeneity of the mantle is demonstrated to the extreme in Lanzarote where a single eruption exhibits compositional variations similar to the span of the OIB worldwide. The extreme heterogeneity is systematic from whole rock lava and tephra at eruption scale but amplified at mineral and melt inclusion scale within a single tephra sample of the eruption.The use of trace element concentrations and ratios of olivine (e.g. Ni, Mn, and Ca) are valuable indicators of the mantle source lithology, namely, the fractionation-corrected Ni x (FeO/MgO) and Fe/Mn as probes of olivine absent or present lithologies, often taken as pyroxenite-derived component in mixtures of primary melts. The measured trace element concentrations in olivine from the 1730-1736 and 1824 eruptions reveal variable mantle lithologies involved in the magma generation with time. Higher Ni and lower Mn and Ca contents are expected when melting Ol-free source, such as pyroxenite lithologies. The basanites exhibit the largest variation covering the range of olivine in MORB and OIB worldwide whereas later produced alkali-basalts and tholeites have values typically expected from pyroxenite derived melts. The Fo content decreases systematically with time during the 1730-36 eruption and the proportion of silica-saturated primary melt increased in the parental magma mixture with time. At the end of the eruption, tholeiite magmas crystallized olivine with lower Fo content, whereas those concentrations of Mn and Ca increased together with Ca/Al at relatively uniform Ni x (FeO/MgO) and Fe/Mn, all of which is readily explained by increased decompression melting at slightly lower temperature. The basanite from the eruption that took place in 1824 has olivine with the highest Fo content and trace element variability expanding the range of the Timanfaya basanite. The fact that Lanzarote basanites contain olivine with trace element systematic spanning that of MORB and pyroxenite melt is explained by CO2-flux melting of a lithologically heterogeneous source, generating the diverse compositions. In addition, early reactive porous flow through the depleted oceanic lithosphere and equilibration with harzburgite restite caused Ni depletion of the earliest percolating pyroxenite melt from which olivine crystallized and probably leaving dunite channels. After the channel formation mantle nodules could be brought to the surface. The fact that olivine compositions and basanite magma were reproduced approximately a century later may reflect episodic carbonatic fluxing in the slowly uprising Canarian mantle plume. (...)
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Peterman, Kenneth James. "Determination of Oxygen Fugacity using Olivine-Melt Equilibrium: Implications for the Redox States of Mid-Ocean Ridge Basalt and Ocean Island Basalt Mantle Source Regions." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1502803559889083.

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Simonetti, Antonio Carleton University Dissertation Earth Sciences. "Comparative Nd, Pb, and Sr isotopic study of alkalic complexes from East Africa and India; implications for mantle source regions, melt dynamics and fluid processes." Ottawa, 1994.

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Mollex, Gaëlle. "Architecture de la plomberie du volcan carbonatitique Oldoinyo Lengai : nouvelles contraintes sur la source, les transferts hydrothermaux, et la différenciation magmatique dans la chambre active." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0123/document.

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La particularité de l’Oldoinyo Lengai à émettre des laves natrocarbonatitiques fait de ce volcan un laboratoire naturel pour l’étude de la genèse de ces magmas. De nouvelles mesures isotopiques en hélium nous ont permis de constater que la signature des fumerolles est constante depuis 1988 malgré le changement morphologique considérable du cratère sommital lors de la dernière éruption subplinienne de 2007-2008. L’alternance des éruptions explosives et effusives n’engendre donc aucune modification majeure dans l’organisation du système hydrothermal qui est par conséquent profondément enraciné. Les xénolites cogénétiques qui ont été émis lors de l’éruption de 2007-2008 permettent d’étudier directement les processus magmatiques qui se déroulent dans la chambre magmatique active. La comparaison des signatures isotopiques des gaz rares (hélium) de la chambre magmatique et des volcans silicatés de la région d’Arusha montre que les deux types de magmatisme ont une source analogue identifiée comme un manteau lithosphérique subcontinental préalablement métasomatisé par des fluides asthénosphériques. De plus, ces signatures isotopiques confirment l’absence de contaminations crustale lors de la remontée du magma entre le manteau source et la surface. Une description pétrographique de détail couplée à une approche thermobarométrique, ainsi qu’à la détermination des modèles de solubilité des volatils dans les liquides phonolitiques, nous a permis d’identifier l’évolution du liquide dans la chambre magmatique et ses paramètres de stockage. Les résultats nous révèlent que le magma injecté en 2007 a une composition phonolitique et des teneurs élevées en volatils (3.2 wt.% de H2O et 1.4 wt.% de CO2) ainsi qu’une température d'environ 1060° C. Ce magma évolue ensuite dans la chambre magmatique crustale se trouvant à 11.5±3.5 km de profondeur jusqu’à atteindre une composition de néphélinite et une température de 880°C. Pendant sa différenciation, le magma silicaté s’enrichit en calcium, sodium, magnésium et fer alors que sa concentration en silice, potassium et aluminium décroit. Ces résultats concordent avec les précédents relatifs à cette éruption, ou aux produits volcaniques plus anciens émis tout au long de la vie du volcan. Cette similarité suggère qu’aucun changement majeur n’ait eu lieu dans l’organisation de la plomberie du volcan Oldoinyo Lengai au cours de son évolution. Les mesures en éléments traces (REE, HFSE et LILE) dans les minéraux cristallisés lors de cette séquence de différenciation, et les inclusions magmatiques associées montrent un enrichissement pouvant atteindre de 100 à 1000 fois la composition du manteau primitif. Une étude expérimentale préliminaire s’appuyant sur la composition du liquide de recharge (phonolite) et les conditions (P, T) identifiées pour la chambre magmatique nous a permis de reproduire l'immiscibilité entre un liquide silicaté et carbonatitique, processus à l’origine de la formation des carbonatites de l’Oldoinyo Lengai. La poursuite de ces travaux expérimentaux permettra de mieux contraindre la genèse des magmas carbonatitiques et ainsi comprendre les processus en jeux dans l’enrichissement en éléments traces des magmas carbonatitiques
The uniqueness of Oldoinyo Lengai to emit natrocarbonatite lavas makes this volcano a natural laboratory to study the genesis of these magmas. New helium isotopic data permit to assert that the signature of the fumaroles has been constant since 1988 despite the radical morphological change of the summit crater after the last sub-Plinian eruption in 2007-2008. The alternation of the effusive and explosive eruptions does not cause major modifications in the hydrothermal system architecture, which is inferred to be deeply rooted. Cognate xenoliths that were emitted during the eruption in 2007-2008 represent a unique opportunity to document the igneous processes occurring within the active magma chamber. The comparison between the noble gas (helium) isotopic compositions of the active magma chamber and those of the other silicate volcanoes of the Arusha region indicates that both types of magmatism have similar sources, identified as being a typical sub-continental lithospheric mantle, which was previously metasomatized by asthenospheric fluids. Moreover, these isotopic signatures confirm that no crustal contamination has occurred during the magma ascent from the mantle to the surface. Detailed petrographic descriptions coupled to a thermo-barometric approach, and to the determination of volatile solubility models for a phonolite composition, allow us to identify the melt evolution at magma chamber conditions and the storage parameters. These results indicate that the magma injected in 2007 has a phonolitic composition and contains a high amount of volatiles (3.2 wt.% H2O and 1.4 wt.% CO2) as well as a temperature around 1060° C. This magma subsequently evolved in the crustal magma chamber located at 11.5 ± 3.5 km depth until reaching a nephelinite composition and a temperature of 880°C. During the differentiation in the magma chamber, the silicate magma is enriched in calcium, sodium, magnesium and iron, whereas the content of silicate, potassium and aluminum decreases. Our results support previous studies related to this eruption, and are similar to the historical products emitted during the whole volcano history, permitting the suggestion that no major modification in the plumbing system has occurred during the Oldoinyo Lengai evolution. The trace elements (REE, LILE and HFSE) measured in the minerals and melt inclusions reveal a concentration reaching 100 to 1000 times the primitive mantle composition. A preliminary experimental study based on the recharge melt composition (phonolite) and identified magma chamber conditions (P, T) permits to reproduce the immiscibility between silicate and carbonatite liquids, key processes at the origin of the Oldoinyo Lengai carbonatites. The continuation of this experimental study will lead to a better comprehension of the carbonatite genesis, thus improving our understanding of the processes that are responsible for the enrichment in trace elements
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Valer, Marina. "Origine et évolution des magmas de l'île de la Réunion : apports de la pétro-géochimie et des inclusions magmatiques." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22775/document.

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Malgré l’homogénéité isotopique des laves de La Réunion, une certaine diversité des produits est observée sur les deux principaux volcans de l’île, le Piton des Neiges et le Piton de la Fournaise, d’un point de vue pétrographique et chimique. En effet, si la majorité des laves émises sont des basaltes transitionnels dont l’évolution est principalement contrôlée par la précipitation et/ou l’accumulation d’olivine, certaines laves plus ou moins anciennes montrent des caractéristiques pétrologiques et géochimiques particulières, qui témoignent de conditions magmatiques variées et de systèmes de stockage et transfert relativement complexes. C’est le cas des « Basaltes Porphyriques à Plagioclase », des basaltes des cônes excentriques dits « adventifs » et de ceux du cratère Hudson (éruption de 1998), sur lesquels portent les travaux de cette thèse. L’étude pétro-géochimique des laves est couplée à celle des inclusions magmatiques des minéraux, naturellement vitreuses ou homogénéisées par chauffage expérimental, afin de caractériser l’origine des magmas et les processus responsables de leur évolution, en contexte de point chaud océanique. Les rapports d’éléments en traces incompatibles des inclusions magmatiques piégées dans les olivines précoces (Fo > 85) des cônes adventifs sont utilisés pour identifier la nature de la source du panache mantellique de La Réunion. Les résultats suggèrent que les magmas des cônes adventifs ont une origine chimiquement comparable à celle de l’ensemble des laves réunionnaises, intermédiaire entre un domaine mantellique relativement primitif et un domaine légèrement appauvri, presque non-affecté par les processus de recyclage. De faibles degrés de fusion partielle de cette source génèrent les concentrations enrichies en éléments en traces des inclusions magmatiques. Les Basaltes Porphyriques à Plagioclases, pouvant contenir jusqu’à 35 % de plagioclases millimétriques, ont été émis sur les deux volcans. Les compositions des inclusions magmatiques des macrocristaux de plagioclase (An 84.2-71.7 ) et les observations texturales des cristaux mettent en évidence leur caractère hérité. Les magmas parentaux des cristaux évoluent essentiellement par cristallisation de clinopyroxène et de plagioclase. Les contrastes de densité entre les phases permettent la ségrégation des plagioclases par flottaison, et leur accumulation au toit de la chambre. Les Basaltes Porphyriques à Plagioclase sont formés par la remobilisation de ces zones d’accumulation riches en plagioclase lors de l’arrivée d’un nouveau magma. Les périodes très spécifiques d’éruption de ces basaltes correspondraient à une diminution du flux magmatique dans la croissance des volcans, favorisant la cristallisation de plagioclase. Les textures des laves des cônes adventifs et du cratère Hudson, ainsi que les inclusions magmatiques des olivines de ces laves témoignent d’une histoire complexe des cristaux, et de l’importance des processus de recyclage dans le système d’alimentation magmatique du Piton de la Fournaise. Les olivines sont nettement plus magnésiennes (Fo > 85) que celles des laves historiques. Les compositions chimiques des laves montrent que la majeure partie correspond à des basaltes légèrement alcalins, appelés « Mid-Alkaline Basalts », qui sont appauvris en CaO mais enrichis en éléments compatibles et incompatibles. Les compositions isotopiques et en éléments en traces leurs suggèrent une origine commune avec celle des laves historiques, bien que le taux de fusion partielle à l’origine des « Mid-Alkaline Basalts » soit plus faible. Un fractionnement profond de clinopyroxène et de plagioclase expliquerait leur formation. L’ensemble de ces résultats suggère que du magma d’origine profonde peut remonter directement, sans passer par le système central du volcan
Despite the isotopic homogeneity of the La Réunion lavas, a petrographic and chemical diversity is observed in the products of the two main volcanoes of the island, le Piton des Neiges and le Piton de la Fournaise. Although the majority of the lavas are transitional basalts which are mainly controlled by olivine fractionation and/or accumulation, some relatively old lavas show petrological and geochemical characteristics that reflect various and relatively complex magmatic conditions, as well as storage and plumbing systems. This is for instance the case of the Plagioclase Ultraphyric-Basalts, basalts from the eccentric ‘adventive’ cones and from the Hudson crater (1998 eruption), on which this works deals with. The petro-geochemical study of the lavas is coupled with the investigation of naturally vitreous or experimentally quenched mineral-hosted melt inclusions, in order to characterize the origin of the magmas and their evolution processes in an oceanic hotspot context. The incompatible trace element ratios of the melt inclusions trapped within early-formed olivine crystals (Fo > 85) from the adventive cones are used to identify the nature of the La Réunion mantle plume source. The results suggest that magmas of the adventive cones originate from chemical source comparable to that of all the La Réunion lavas. This source is intermediate between a primitive-like mantle domain and a depleted one, almost unaffected by recycling processes. Small degrees of melting of this source can explain the enriched trace element concentrations of the melt inclusions. Plagioclase-bearing ultraphyric basalts, which can have up to 35 % millimetre-sized plagioclase crystals, were erupted during some stages of building of the two volcanoes. The compositions of the melt inclusions hosted in the plagioclase macrocrystals (An 84.2-71.7 ) and textural observations of the crystals highlight their inherited character. The parental melts of the crystals mainly evolve by clinopyroxene and plagioclase crystallization. Density contrasts between the phases allow plagioclase segregation by flotation and their accumulation at the top of the chamber. The Plagioclase Ultraphyric-Basalts are derived from the remobilization of this plagioclase-rich accumulation zones, upon input of a new batch of magma. The specific eruption periods of these basalts would correspond to decreases in the magma supply, which promoted plagioclase crystallization. Lava textures of the adventive cones and Hudson crater and their olivine-hosted melt inclusions reflect a complex history of the crystals, and the role of recycling processes in the magma feeding system of the Piton de la Fournaise volcano. The olivine crystals are clearly more magnesian (Fo > 85) than those found in the historical lava ones. The chemical compositions of the lavas show that they correspond for the most part to slightly alkaline basalts, called “Mid-Alkaline Basalts”, which are depleted in CaO and enriched in compatible and incompatible elements. Isotopic and trace element compositions suggest that they have a common origin with the historical lavas, but partial melting degrees are lower for the “Mid-Alkaline Basalts”. Clinopyroxene and plagioclase deep fractionation would explain their formation. All the results suggest that the ascent of deep-seated magma clearly could bypass the central volcanic system
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Sorbadère, Fanny. "Apport des inclusions magmatiques et de la fusion expérimentale d'une source mixte péridotite-pyroxénite à l'étude des mécanismes de genèse des magmas d'arc sous-saturés en silice." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00814866.

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Les laves émises en domaine de subduction sont dominées par des compositions calcoalcalines à hypersthène normatif. En revanche, les inclusions magmatiques piégées dans les olivines magnésiennes (Fo ≥ 88) des basaltes d'arc présentent des compositions alcalines, à néphéline normative. Bien que leurs compositions en éléments traces incompatibles ne diffèrent pas de celles de leurs laves hôtes, ces magmas ne peuvent pas s'expliquer par les modèles classiques de formation des laves d'arc. L'étude d'inclusions magmatiques alcalines de plusieurs arcs du monde a permis de mettre en évidence leur variabilité de composition, en particulier en CaO et Sc, deux éléments compatibles dans le clinopyroxène. Le couplage de cette étude avec des modélisations thermodynamiques a aboutit à l'élaboration d'un modèle de source impliquant la contribution de clinopyroxénites à amphibole à environ 1 GPa. Les inclusions magmatiques à néphéline normative d'arc seraient ainsi les témoins de l'hétérogénéité de source à l'origine des magmas d'arc. Les expériences de fusion partielle du mélange homogène clinopyroxénite à amphibole - péridotite hydratée réalisées à 1 GPa permettent d'apporter des informations supplémentaires quant aux mécanismes de genèse des magmas d'arc sous-saturés en silice et de mieux comprendre les comportements de fusion des deux types de lithologies. Pour des proportions inférieures à ~ 50 % de pyroxénite dans la source, les magmas produits présentent des compositions à hypersthène normatif, comparables aux laves d'arc issues de la fusion de lithologies péridotitiques. Pour des proportions de pyroxénites supérieures, les magmas sont à néphéline normative et s'enrichissent en calcium, reproduisant ainsi la gamme de compositions observée pour les inclusions magmatiques. 50 % de mélange correspond à la limite de stabilité de l'orthopyroxène. Tant que cette phase est présente dans le résidu, les magmas engendrés restent à hypersthène normatif. De plus, la présence d'amphibole dans la source permet d'augmenter la sous-saturation des liquides résultants et d'expliquer ainsi les termes les plus riches en néphéline normative de certaines inclusions. Nos expériences de fusion d'une source homogène ont également permis de déterminer la composition des magmas formés par un processus de fusion plus réaliste, impliquant une source hétérogène pyroxénite-péridotite. La productivité de liquides des pyroxénites étant supérieure à celles des péridotites, les magmas générés à partir d'une source hétérogène seront donc principalement pyroxénitiques, c'est-à-dire davantage sous-saturés en silice. Ainsi, dans le cas d'un mélange de magmas issus d'une source hétérogène, la transition entre les compositions à hypersthène et à néphéline normatifs s'effectue aux alentours de 30-40 % de liquides pyroxénititiques, soit pour environ 20-25 % de pyroxénite dans la source. L'origine de ces lithologies dans le manteau sub-arc est attribuée à la délamination de cumulats à clinopyroxène + amphibole présents à la base de la croute des arcs. Les inclusions magmatiques à néphéline normative d'arc auraient enregistré plusieurs étapes de mélange entre des liquides quasi-purs de clinopyroxénites et des liquides péridotitiques. L'homogénéité de compositions des laves à hypersthène normatif traduirait en revanche, un stade de mélange et de différenciation plus avancé, atténuant ainsi la signature pyroxénitique.
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Lea, Emma J. "Moving from meat : vegetarianism, beliefs and information sources." Connect to this title online, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phl4335.pdf.

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Includes bibliographical references (leaves 327-346). A random population survey and a survey of vegetarians were conducted to examine South Australians' beliefs about meat and vegetarianism. Meat beliefs, barriers and benefits of vegetarianism, meat consumption, personal values, use of and trust in sources of food/nutrition/health information and demographic variables were measured.
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8

Narciso-Gaytan, Carlos. "Dietary lipid source and vitamin e influence on chicken meat quality and lipid oxidation stability." Thesis, [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2746.

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Valantin, Muriel. "Fécondation, environnement climatique, équilibre source-puits et qualité du melon cantaloup charentais (cucumis melo L. )." Aix-Marseille 3, 1998. http://www.theses.fr/1998AIX30023.

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Nous avons modifie la charge en fruits et leur contenu en graines pour moduler les relations source-puits de la plante et determiner leur influence sur les criteres de qualite du fruit et sur la genese de la vitrescence, une alteration physiologique de la chair du melon cantaloup charentais. Nous avons caracterise sur 2 annees et avec 2 varietes le developpement et l'activite photosynthetique de l'appareil vegetatif aerien, le developpement et la croissance des fruits, la repartition des assimilats au sein de la plante entiere, et la qualite des fruits et l'incidence de la vitrescence a la recolte. Le fruit constitue un puits fort au sein de la plante entiere a cause du cout energetique eleve des graines. Sur les plantes en nouaison libre, l'essentiel de la nouaison s'est fait sur 5 jours et la photosynthese nette foliaire n'a pas ete stimulee, mais la photosynthese nette du couvert, et donc la production globale d'assimilats, a ete reduite du fait d'une diminution de la vitesse d'apparition des feuilles. Dans cette situation de competition pour les assimilats, la vitesse de croissance des fruits etait diminuee ainsi que leur calibre individuel, la fermete de la chair et sa teneur en sucres a maturite tandis que l'incidence de la vitrescence etait accrue par rapport a des fruits produits en l'absence de competition sur des plantes avec un seul fruit noue. La taille du fruit etait bien correlee a son contenu en graines pleines et un faible contenu en graines s'est traduit par une chair plus ferme et une moindre sensibilite a la vitrescence. Ces resultats, avec ceux d'une etude preliminaire sur l'appareil racinaire, ont ete integres dans un schema d'elaboration des principaux criteres de qualite du melon et d'apparition de la vitrescence.
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Gennaro, Mimma Emanuela. "Sulfur behavior and redox conditions in Etnean hydrous basalts inferred from melt inclusions and experimental glasses." Thesis, Orléans, 2017. http://www.theses.fr/2017ORLE2005/document.

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Le soufre est un composant volatil important des magmas qui présente différents états d'oxydation en fonction des conditions d’oxydoréduction et de la phase dans laquelle il se trouve : dans le liquide silicaté, il est typiquement dissous comme S⁶⁺ et/ou S²⁻ , dans la phase gazeuse il se trouve principalement comme SO₂ (S⁴⁺ ) et H₂S (S²⁻). L’Etna, pour lequel les conditions d’oxydoréduction sont faiblement contraintes, est utilisée comme cas d’étude pour examiner le comportement du soufre dans les magmas basaltiques hydratés pendant la différenciation et le dégazage. Cette recherche combine l'étude des inclusions vitreuses avec une étude expérimentale en conditions magmatiques sur la solubilité du S dans les basaltes alcalins hydratés.Les résultats expérimentaux suggèrent l’important contrôle de la ƒO₂ sur la teneur en S dans les magmas hydratés de l’Etna, et le partage du S entre les phases fluid and liquid. Les inclusions vitreuses ont été piégées à différentes profondeurs à l'intérieur du système magmatique. Elles décrivent une tendance continue de différenciation, marquée par une cristallisation fractionnée, à partir de la composition picritique (FS) vers le basalte plus récent dégazé (2013). Le contenu en S dans le liquide de l'Etna est extrêmement variable et atteint 4150 ppm dans les inclusions vitreuses les plus primitives. Les spectres XANES Fe³⁺/ΣFe des certaines inclusions vitreuses donnent des rapports Fe³⁺/ΣFe généralement décroissants à partir du liquide le plus primitif (FS) jusqu’au plus évolué (2013). Les simulations effectué par le logiciel MELTS confirme que la diminution du rapport Fe³⁺/ΣFe est principalement due au processus de différenciation magmatique, renforcé par le dégazage du S à ƒO₂ < NNO + 1. Cette réduction du magma provoque à son tour la diminution de la solubilité du S dans les basaltes hydratés de l’Etna, et peut constituer un éventuel activateur de l’exsolution du S, à l’origine de l’important dégazage du S observé au cours des dernières décennies à l’Etna
Sulfur is an important volatile component of magmas that presents different oxidation states, depending on the redox conditions and on the phase of occurrence: in silicate melts it is typically dissolved as S⁶⁺ and/or S²⁻ , in the gas phase it occurs principally as SO₂ (S⁴⁺ ) and H₂S (S²⁻). Mount Etna, in which magmatic redox conditions are poorly constrained, is used as a case study to investigate sulfur behavior in hydrous basaltic magmas during magma differentiation and degassing. This research integrates the study of natural olivine-hosted melt inclusions with an experimental study on S solubility in hydrous alkali basalts at magmatic conditions.Experimental results suggest the important control of ƒO₂ on the S abundance in Etnean hydrous magma and its partitioning between fluid and melt phases. Melt inclusions were entrapped at different depths inside the magmatic system (up to ~ 18 km, below crater level). They delineate a continuous differentiation trend, marked by fractional crystallization, from the picritic basalt (FS) toward the most evolved and degassed (2013) basalt. S content in Etnean melt is extremely variable and reaches 4150 ppm in the primitive melt inclusions. XANES Fe³⁺/ΣFe spectra in some glass inclusions, resulted in the generally decreasing of Fe³⁺/ΣFe ratios from the most primitive (FS) to the most evolved (2013) melts. MELTS software confirms that the Fe³⁺/ΣFe decrease is due principally to the melt differentiation process, enhanced to the S degassing at ƒO₂ < NNO+1. Magma reduction, in turn, induces the decrease of the sulfur solubility in the hydrous Etnean basalt, as well as of the sulfide saturation, and may constitute a possible enhancer of S exsolution, triggering the important S degassing observed in the last decades in Mt. Etna
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Books on the topic "Melt source"

1

Berry, Brad W. Meat freezing: A source book. Amsterdam: Elsevier, 1989.

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To meet at the source: Hindus & Quakers. Wallingford, Pa: Pendle Hill Publications, 1989.

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Taylor, C. Michael. Meet the registrar: Firsthand accounts of ISO 9000 success from the Registration source. Milwaukee, Wis: ASQC Quality Press, 1997.

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Vișoianu, Constantin. Misiunile mele: Culegere de documente. București: Editura Enciclopedia, 1997.

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Dr, Singh K. K., Mathur A. N. 1945-, Rathore N. S. 1960-, and India. Dept. of Non-Conventional Energy Sources., eds. Advances in biomass gasification technology: Proceeding of IInd national MEET/PICCOP meet, December 20-21, 1990. Udaipur, Rajasthan: Himanshu Publications, 1991.

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Elzufon, Betsy. Residential and commercial source control programs to meet water quality goals: Project 95-IRM-1, 1998. Alexandria, VA: Water Environment Research Foundation, 1998.

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Tomisa, Ilona. "Mely hív szolgálattyáért Esztendőbéli fizetése lészen": Szemelvények a Dessewffy család XVIII. századi gazdasági irataiból. Budapest: L' Harmattan, 2003.

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Skuodis, Vytautas. Melo, neapykantos ir šmeižto kronika, 1993-1997 metai. Vilnius: Gairės, 2007.

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Ending the energy stalemate: A bipartisan strategy to meet America's energy challenges. [Washington, DC]: National Commission on Energy Policy, 2004.

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Breviarium caeremoniarum monasterii Mellicensis. Siegburg: Apud Franciscum Schmitt Success., 1987.

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Book chapters on the topic "Melt source"

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Percival, J. A. "Melt-Induced Fluid Pumping and the Source of CO2 in Granulites." In Fluid Movements — Element Transport and the Composition of the Deep Crust, 61–69. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0991-5_6.

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Wang, Bitong, Andrew Caldwell, Antoine Allanore, and Douglas H. Kelley. "Investigation of Echo Source and Signal Deterioration in Ultrasound Measurement of Metal Melt." In The Minerals, Metals & Materials Series, 495–506. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92381-5_46.

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Behera, Bhuban M., V. Thirukumaran, Neeraj Kumar Sharma, and Tapas Kumar Biswal. "A Preliminary Study on Earthquake Source Properties Based on Geochemistry, Shear Resistance and Melt Pressure of Pseudotachylites, Gangavalli Fault, South India." In Society of Earth Scientists Series, 175–97. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-40593-9_8.

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Banerjee, Rituparna, Arun K. Verma, B. M. Naveena, and V. V. Kulkarni. "Processing, Storage, and Transportation of Meat and Meat Products." In Animal Sourced Foods for Developing Economies, 77–117. Boca Raton, FL : Taylor & Francis, 2019. | Series: World Food Preservation Center book series: CRC Press, 2018. http://dx.doi.org/10.1201/9780429398575-5.

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Mukherjee, Sudipta. "Meet Roslyn Syntax API." In Source Code Analytics With Roslyn and JavaScript Data Visualization, 1–14. Berkeley, CA: Apress, 2016. http://dx.doi.org/10.1007/978-1-4842-1925-6_1.

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Azimova, Shakhnoza S., and Anna I. Glushenkova. "Cucumis melo L." In Lipids, Lipophilic Components and Essential Oils from Plant Sources, 294–96. London: Springer London, 2012. http://dx.doi.org/10.1007/978-0-85729-323-7_931.

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Schmidt, H. "Impurities in Meat — Sources and Influences." In Safeguarding Food Quality, 147–56. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-78025-7_13.

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Azimova, Shakhnoza S., and Anna I. Glushenkova. "Melo sativus Sageret ex M. Roem. (Cucumis melo L., C. chaete Wall.)." In Lipids, Lipophilic Components and Essential Oils from Plant Sources, 316. London: Springer London, 2012. http://dx.doi.org/10.1007/978-0-85729-323-7_977.

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Jobling, A. "Food proteins from red meat by-products." In New and Developing Sources of Food Proteins, 31–50. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2652-0_2.

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Delgado, Amélia Martins, Salvatore Parisi, and Maria Daniel Vaz Almeida. "Fish, Meat and Other Animal Protein Sources." In Chemistry of the Mediterranean Diet, 177–207. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-29370-7_7.

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Conference papers on the topic "Melt source"

1

Tovey, Madeline, Andrea Giuliani, David Phillips, Chiranjeeb Sarkar, Graham Pearson, Tom Nowicki, and Jon Carlson. "Decoupling of Kimberlite Source and Primitive Melt Compositions." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.2618.

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Böhnke, Mischa, Felix Genske, and Andreas Stracke. "Mantle Source Heterogeneity Inferred from Olivine-Hosted Melt Inclusions." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.214.

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Rosseel, E., J. P. Lu, A. Hikavyy, P. Verheyen, T. Hoffmann, O. Richard, J. Geypen, et al. "Impact of sub-melt laser annealing on Si1-xGex source /drain defectivity." In 2007 15th International Conference on Advanced Thermal Processing of Semiconductors. IEEE, 2007. http://dx.doi.org/10.1109/rtp.2007.4383859.

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Nemchinsky, Valerian. "Melting Rate of a Solid With Periodic Melt Removal." In ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-1035.

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Abstract The melting rate of a solid, subjected to a heat flux at its surface, changes with time. When a fresh unmelted surface is first exposed to a heat source, the melting isotherm moves quickly inside the solid. Then its motion slows down: this decrease in melting rate is obviously because of increasing thermal resistance of the growing liquid layer that separates solid-liquid interface from the heat source. If the liquid layer is not removed, the melting rate approaches zero. The resultant melting rate depends on the manner in which the melt is removed. In a number of cases of practical interest, the melt is removed not continuously but periodically, in the form of drops. For example, during arc welding with a consumable electrode, these drops are accumulated at the tip of the electrode. When the drop becomes big enough, it is detached from the electrode under action of gravity or electromagnetic force the melt is removed not continuously but periodically, in the form of drops. A simple approximate method is suggested to calculate the melting rate of a solid in the case when melt is removed periodically in form of drops. The method allows one to consider separately the heat transfer in the solid and in the liquid and, thus, to include different heat processes in both phases. Good agreement was demonstrated for exact and approximate solutions for a wide range of parameters.
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Luo, Zhibo, and Yaoyao Fiona Zhao. "Finite Element Thermal Analysis of Melt Pool in Selective Laser Melting Process." In ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85701.

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Selective laser melting is one of the powder bed fusion processes which fabricates a part through layer-wised method. Due to the ability to build a customized and complex part, selective laser melting process has been broadly studied in academic and applied in industry. However, rapidly changed thermal cycles and extremely high-temperature gradients among the melt pool induce a periodically changed thermal stress in solidified layers and finally result in a distorted part. Therefore, the temperature distribution in the melt pool and the size and shape of the melt pool directly determine the mechanical and geometrical property of final part. As experimental trial-and-error method takes a huge amount of cost, different numerical methods have been adopted to estimate the transient temperature and thermal stress distribution in the melt pool and powder bed. The most existing research utilizes the moving Gaussian point heat source to model the profile of the melt pool, which consumes a significant amount of computational cost and cannot be used to implement the part-level simulation. This research proposes a new line heat source to replace the moving point heat source. Some efforts are applied to reduce the computational cost. Specifically, a relatively large step size is used for the line heat source to reduce the number of time steps. In addition, a mesh refinement scheme is adopted to reduce the number of cells in each time step by refining the mesh close to the heat source and coarsening the mesh far away from it. On the other hand, efforts are implemented to increase the accuracy of the simulation result. Temperature-dependent material properties are considered in this FE framework. In addition, material transition among powder, liquid, and solid are incorporated in the developed FE framework. In this study, temperature simulation of one scanning track based on self-developed FE code is applied for Stainless Steel 316L. The simulation results show that the temperature distribution and history of melt pool within line heat source are comparable to that of the moving Gaussian point heat source. While the simulation time is reduced by more than two times depending on the length of line heat input. Therefore, this FE model can be used to numerically investigate the process parameters and help to control the quality of the final part.
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Itoh, Hiroto, Xiaoyu Zheng, Hitoshi Tamaki, and Yu Maruyama. "Influence of In-Vessel Melt Progression on Uncertainty of Source Term During a Severe Accident." In 2014 22nd International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/icone22-30012.

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The influence of the in-vessel melt progression on the uncertainty of source terms was examined in the uncertainty analysis with integral severe accident analysis code MELCOR (Ver. 1.8.5), taking the accident at Unit 2 of the Fukushima Daiichi nuclear power plant as an example. The 32 parameters selected from the rough screening analysis were sampled by Latin hypercube sampling technique in accordance with the uncertainty distributions specified for each parameter. The uncertainty distributions of the outputs, including the source terms of the representative radioactive materials (Cs, CsI, Te and Ba), the total mass of in-vessel H2 generation and the total debris mass released from the reactor pressure vessel to the drywell, were obtained through the uncertainty analysis with an assumption of the failure of drywell. Based on various types of correlation coefficient for each parameter, 9 significant uncertain parameters potentially dominating the source terms were identified. These 9 parameters were transferred to the subsequent sensitivity and uncertainty analyses, in which the influence of the transportation of radioactive materials was taken into account.
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Bracco Gartner, Antoine, Igor Nikogosian, Jan Aartsen, Cathy Gonggrijp, Natascia Luciani, Gareth Davies, and Janne Koornneef. "The mantle source of lamproites from Torre Alfina, Italy: Evidence from melt inclusions in olivine." In Goldschmidt2022. France: European Association of Geochemistry, 2022. http://dx.doi.org/10.46427/gold2022.11161.

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Khoury, Regina, Celestine N. Mercer, Albert Hofstra, and Lisa Stillings. "Melt Inclusion Insights on Rhyolites Proposed as a Source of Economic Lithium in Clayton Valley, Nevada." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.1290.

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Jiang, Peng, Michael Perfit, Molly Anderson, George Kamenov, and Andres Trucco. "“Probing” mantle source compositions and melt evolution beneath the northern East Pacific Rise using olivine geochemistry." In Goldschmidt2022. France: European Association of Geochemistry, 2022. http://dx.doi.org/10.46427/gold2022.12772.

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Zhang, Yaqi, Vadim Shapiro, and Paul Witherell. "A Neighborhood-Based Neural Network for Melt Pool Prediction and Control." In ASME 2020 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/detc2020-22549.

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Abstract One of the most prevalent additive manufacturing processes, the powder bed fusion process, is driven by a moving heat source that melts metals to build a part. This moving heat source, and the subsequent formation and moving of a melt pool, plays an important role in determining both the geometric and mechanical properties of the printed components. The ability to control the melt pool during the build process is a sought after mechanism for improving quality control and optimizing manufacturing parameters. For this reason, efficient models that can predict melt pool size based on the process input (i.e., laser power, scan speed, spot size and scan path) offer a path to improved process control. Towards improved process control, a data-driven melt pool prediction model is built with a neighborhood-based neural network and trained using experimental data from the National Institute of Standards and Technology (NIST). The model considers the influence of both manufacturing parameters and laser scan paths. The scan path information is encoded using two novel neighborhood features of the neural network through locality. The neural network is used to generate a surrogate model, and we demonstrate how the performance of the resulting surrogate model can be further improved by using several ensemble methods. We then demonstrate how the trained surrogate model can be used as a forward solver for developing novel laser power design algorithms. The resulting laser power plan is designed to keep melt pool size as constant as possible for any given scan pattern. The algorithm is implemented and validated with numerical experiments.
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Reports on the topic "Melt source"

1

Stone, M. E., and D. P. Lambert. Feed Preparation for Source of Alkali Melt Rate Tests. Office of Scientific and Technical Information (OSTI), February 2005. http://dx.doi.org/10.2172/881519.

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Forsberg, C. W., G. W. Parker, J. C. Rudolph, I. W. Osborne-Lee, and M. A. Kenton. Termination of light-water reactor core-melt accidents with a chemical core catcher: the core-melt source reduction system (COMSORS). Office of Scientific and Technical Information (OSTI), September 1996. http://dx.doi.org/10.2172/453914.

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Smith, M. The Impact of the Source of Alkali on Sludge Batch 3 Melt Rate (U). Office of Scientific and Technical Information (OSTI), April 2005. http://dx.doi.org/10.2172/890167.

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Lever, James, Susan Taylor, Garrett Hoch, and Charles Daghlian. Evidence that abrasion can govern snow kinetic friction. Engineer Research and Development Center (U.S.), December 2021. http://dx.doi.org/10.21079/11681/42646.

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The long-accepted theory to explain why snow is slippery postulates self-lubrication: frictional heat from sliding melts and thereby lubricates the contacting snow grains. We recently published micro-scale interface observations that contradicted this explanation: contacting snow grains abraded and did not melt under a polyethylene slider, despite low friction values. Here we provide additional observational and theoretical evidence that abrasion can govern snow kinetic friction. We obtained coordinated infrared, visible-light and scanning-electron micrographs that confirm that the evolving shapes observed during our tribometer tests are contacting snow grains polished by abrasion, and that the wear particles can sinter together and fill the adjacent pore spaces. Furthermore, dry-contact abrasive wear reasonably predicts the evolution of snow-slider contact area and sliding-heat-source theory confirms that contact temperatures would not reach 0°C during our tribometer tests. Importantly, published measurements of interface temperatures also indicate that melting did not occur during field tests on sleds and skis. Although prevailing theory anticipates a transition from dry to lubricated contact along a slider, we suggest that dry-contact abrasion and heat flow can prevent this transition from occurring for snow-friction scenarios of practical interest.
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Mohammadi, N., D. Corrigan, A. A. Sappin, and N. Rayner. Evidence for a Neoarchean to earliest-Paleoproterozoic mantle metasomatic event prior to formation of the Mesoproterozoic-age Strange Lake REE deposit, Newfoundland and Labrador, and Quebec, Canada. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330866.

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A complete suite of bulk major- and trace-elements measurements combined with macroscopic/microscopic observations and mineralogy guided by scanning electron microscope-energy dispersive spectrometry (SEM-EDS) analyses were applied on Nekuashu (2.55 Ga) and Pelland (2.32 Ga) intrusions in northern Canada, near the Strange Lake rare earth elements (REE) deposit, to evaluate their magmatic evolution and possible relations to the Mesoproterozoic Strange Lake Peralkaline Complex (SLPC). These Neoarchean to earliest-Paleoproterozoic intrusions, part of the Core Zone in southeastern Churchill Province, comprise mainly hypersolvus suites, including hornblendite, gabbro, monzogabbro/monzodiorite, monzonite, syenite/augite-syenite, granodiorite, and mafic diabase/dyke. However, the linkage of the suites and their petrogenesis are poorly understood. Geochemical evidence suggests a combination of 'intra-crustal multi-stage differentiation', mainly controlled by fractional crystallization (to generate mafic to felsic suites), and 'accumulation' (to form hornblendite suite) was involved in the evolution history of this system. Our model proposes that hornblendite and mafic to felsic intrusive rocks of both intrusions share a similar basaltic parent magma, generated from melting of a hydrous metasomatized mantle source that triggered an initial REE and incompatible element enrichment that prepared the ground for the subsequent enrichment in the SLPC. Geochemical signature of the hornblendite suite is consistent with a cumulate origin and its formation during the early stages of the magma evolution, however, the remaining suites were mainly controlled by 'continued fractional crystallization' processes, producing more evolved suites: gabbronorite/hornblende-gabbro ? monzogabbro/monzodiorite ? monzonite ? syenite/augite-syenite. In this proposed model, the hydrous mantle-derived basaltic magma was partly solidified to form the mafic suites (gabbronorite/hornblende-gabbro) by early-stage plagioclase-pyroxene-amphibole fractionation in the deep crust while settling of the early crystallized hornblende (+pyroxene) led to the formation of the hornblendite cumulates. The subsequent fractionation of plagioclase, pyroxene, and amphibole from the residual melt produced the more intermediate suites of monzogabbro/monzodiorite. The evolved magma ascended upward into the shallow crust to form monzonite by K-feldspar fractionation. The residual melt then intruded at shallower depth to form syenite/augite-syenite with abundant microcline crystals. The granodiorite suite was probably generated from lower crustal melts associated with the mafic end members. Later mafic diabase/dykes were likely generated by further partial melting of the same source at depth that were injected into the other suites.
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Jacques, I. J., A. J. Anderson, and S. G. Nielsen. The geochemistry of thallium and its isotopes in rare-element pegmatites. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328983.

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The Tl isotopic and trace element composition of K-feldspar, mica, pollucite and pyrite from 13 niobium-yttrium-fluorine (NYF)-type and 14 lithium-cesium-tantalum (LCT)-type rare-element pegmatites was investigated. In general, the epsilon-205Tl values for K-feldspar in NYF- and LCT-type pegmatites increases with increasing magmatic fractionation. Both NYF and LCT pegmatites display a wide range in epsilon-205Tl (-4.25 to 9.41), which complicates attempts to characterize source reservoirs. We suggest 205Tl-enrichment during pegmatite crystallization occurs as Tl partitions between the residual melt and a coexisting aqueous fluid or flux-rich silicate liquid. Preferential association of 205Tl with Cl in the immiscible aqueous fluid may influence the isotopic character of the growing pegmatite minerals. Subsolidus alteration of K-feldspar by aqueous fluids, as indicated by the redistribution of Cs in K-feldspar, resulted in epsilon-205Tl values below the crustal average (-2.0 epsilon-205Tl). Such low epsilon-205Tl values in K-feldspar is attributed to preferential removal and transport of 205Tl by Cl-bearing fluids during dissolution and reprecipitation. The combination of thallium isotope and trace element data may be used to examine late-stage processes related to rare-element mineralization in some pegmatites. High epsilon-205Tl and Ga in late-stage muscovite appears to be a favorable indicator of rare-element enrichment LCT pegmatites and may be a useful exploration vector.
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Connors, Caitlin, Melanie Cohen, Sam Saint-Warrens, Fan Sissoko, Francesca Allen, Harry Cerasale, Elina Halonen, Nicole Afonso Alves Calistri, and Claire Sheppard. Psychologies of Food Choice: Public views and experiences around meat and dairy consumption. Food Standards Agency, March 2022. http://dx.doi.org/10.46756/sci.fsa.zoc432.

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This report presents findings drawn from qualitative remote ethnography research with 24 UK participants conducted during July and August 2021, plus nine peer-to-peer interviews conducted by main sample participants with their friends and family. This research aimed to build on existing evidence in this area to fill gaps and provide an up-to-date snapshot of UK public experiences. Areas of focus included: Motivations for dietary choices Any gaps between consumer intention and behaviour Trade-offs and contextual differences (e.g. in vs. out-of home behaviours) The roles of specialist diets, substitution approaches, alternatives and ‘imitations’, locally/UK sourced meat and dairy, socio-demographics, culture and family Impact and role of food labelling and terminology The sample represented a range of variables including age, gender, nationality (England, Wales, Northern Ireland), urbanity/rurality, lifestage and household composition - and dietary profile (carnivore, ‘cutting down,’ vegetarian, vegan). This report was informed by an evidence review by the University of Bath on the factors underpinning the consumption of meat and dairy among the general public.
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Barakat, Dr Shima, Dr Samuel Short, Dr Bernhard Strauss, and Dr Pantea Lotfian. https://www.food.gov.uk/research/research-projects/alternative-proteins-for-human-consumption. Food Standards Agency, June 2022. http://dx.doi.org/10.46756/sci.fsa.wdu243.

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The UK is seeing growing interest in alternative protein sources to traditional animal-based proteins such as beef, lamb, pork, poultry, fish, eggs, and dairy. There is already an extensive market in alternative protein materials, however, technological advances combined with the pressure for more sustainable sources of protein has led to an acceleration of innovation and product development and the introduction of a large amount of new alternative protein ingredients and products to the market. These have the potential to dramatically impact on the UK food system. This report is a combination of desk research, based on thorough review of the academic and non-academic literature and of the alternative proteins start-up scene, and presents an analysis of the emerging market for alternative proteins, the potential implications and the potential policy responses that the FSA might need to consider. Four main categories of alternative proteins are presented and reviewed in this report: Plant-based meat substitutes Novel protein sources Proteins and biomass biosynthesised by microorganisms Cultured meat
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Lampe, Jay F., John W. Mabry, and Palmer J. Holden. Comparison of Grain Sources (Barley, White Corn, and Yellow Corn) for Swine Diets and Their Effects on Meat Quality and Production Traits. Ames (Iowa): Iowa State University, January 2004. http://dx.doi.org/10.31274/ans_air-180814-1380.

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Berkowitz, Jacob F., Christine M. VanZomeren, Jaybus J. Price, and Anthony M. Priestas. Incorporating Color Change Propensity into Dredged Material Management to Increase Beneficial Use Opportunities. Engineer Research and Development Center (U.S.), December 2020. http://dx.doi.org/10.21079/11681/39261.

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Dredged materials provide a number of beneficial use opportunities, including beach nourishment, habitat creation and restoration, and other activities. In situ sediment color is important for determining aesthetic and habitat suitability, for beach nourishment, and for other projects. However, dredged materials must meet locally established color compatibility requirements (for example, material cannot be too dark). Often, potential sediment sources are close to meeting specified color thresholds, and previous observations suggest that sediments lighten over time. In response to these observations, this study quantified sediment color change potential in a dredged m aterial management context. Results indicate that dredged material sediment color responded to changes in secondary color components, sediment mixing, and photolytic bleaching improving the sediment color for beneficial use application. Findings allowed for development of a conceptual color change capacity framework and supported development of tools for resource managers to incorporate color change dynamic into planning and operations activities.The following report provides a framework for determining the color change capacity of dredged materials using (1) a comprehensive laboratory approach and (2) a semiquantitative index based on source material and placement location conditions. These tools allow practitioners to incorporate dredged-material color change into resource management decisions, thus increasing beneficial use opportunities.
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