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  • 1
    Publication Date: 2015-11-10
    Description: The Las Cruces deposit is in the eastern end of the Iberian Pyrite Belt (SW Spain). It is currently being mined by Cobre Las Cruces S.A. The main operation is focused on the supergene Cu-enriched zone (initial reserves of 17.6 Mt @ 6.2% Cu). An Au-Ag-Pb–rich gossan resource (3.6 Mt @ 3.3% Pb, 2.5 g/t Au, and 56.3 g/t Ag) occurs in the upper part of the deposit. The Au grade ranges from 0.01 ppm to 〉100 ppm, and occurs as three different Au ore types: (1) Au mineralization in the upper part of the gossan linked to Fe-oxides lithofacies, (2) Au concentration in the lower part of the gossan associated with leached black shales, and (3) Au ore in the cementation zone related to subvertical fractures. A hydroseparation device has been used to obtain heavy mineral concentrates from selected samples of different ore types. Reflected-light microscopy, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and electron probe microanalysis (EPMA) were used to study the separated Au particles. Significant differences between the defined ore types include the Au-bearing lithologies, mineral associations, textural features, particle sizes, morphologies, and fineness. Au-rich minerals include native Au, Au-Ag electrum, and Au-Ag-Hg amalgams. Gold-bearing mineral associations include Pb-oxihalides, Fe-oxides, galena, pyrite, cinnabar, and Ag-sulfosalts. The Au enrichment mechanism in the supergene profile involves (1) dissolution of Au from the primary sulfides as chloride-rich ionic complexes during the weathering of the deposit under subaerial exposure; dissolved Au is transported downward through the supergene profile under acidic and oxidized conditions; (2) destabilization of the Au complexes by Fe-controlled redox reactions; as a consequence, coarse-grained, high-fineness Au particles precipitated in association with Fe-oxyhydroxides. This resulted in secondary concentration in the upper gossan; and (3) after deposition of cover sediments took place a progressive change in the system conditions resulting in a later Au remobilization as hydroxidehalide, hydroxide, thiosulfate, and bisulfide complexes in the lowermost gossan and cementation zone. The main pathways for migration of enriched fluids to the cementation zone are secondary permeability zones linked to Alpine reactivated faults. Deposition of Au seems to be related to fluid interaction with reductant lithologies, including black shales and the primary sulfides.
    Print ISSN: 0361-0128
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  • 2
    Publication Date: 2008-08-01
    Description: The Draa Sfar mineralization consists of two main stratabound orebodies, Sidi M’Barek and Tazacourt, located north and south of the Tensift River (“Oued Tessift”), respectively. Each orebody is comprised by at least two massive sulfide lenses. The hosting rocks are predominantly black shales, although minor rhyolitic rocks are also present in the footwall to the southern orebody. Shales, rhyolitic volcanic rocks, and massive sulfides are all included into the Sarhlef Series, which is recognized as one of the main stratigraphic units of the Moroccan Variscan Meseta. Hydrothermal activity related with an anomalous thermal gradient, together with a high sedimentation rate in a tectonically driven pull-apart marine basin, favored the accumulation of organic-rich mud in the deepest parts of the basin and the sedimentary environment suitable for massive sulfide deposition and preservation. This took place by replacement of the hosting unlithified wet mud below the sediment–water interface. Geochemical data suggest a sedimentary environment characterized by oxic water column and anoxic sediment pile with the redox boundary below the sediment–water interface. The low oxygen availability within the sediment pile inhibited oxidation and pyritization of pyrrhotite. Biostratigraphic analysis, based on the palynological content of the hosting black shales, restricts the age of the sulfides to the Asbian substage (mid-Mississippian). This age is consistent with earlier geochronological constraints. ©2008 Springer-Verlag
    Print ISSN: 0026-4598
    Electronic ISSN: 1432-1866
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  • 3
    Publication Date: 1998-11-19
    Description: The sulphide deposits of the Iberian Pyrite Belt (IPB) represent an ore province of global importance. Our study presents 113 new sulphur isotope analyses from deposits selected to represent the textural spectrum of ores. Measured 34S values range from −26 to +10‰ mostly for massive and stockwork ores, in agreement with data previously published. In situ laser 34S analyses reveals a close correlation of 34S with texture. Primary diagenetic textures are dominated by relatively low 34S (−8‰ to −2‰), whereas stockwork feeder textures are dominated by higher 34S (∼+3‰ to +5‰). Intermediate textures (mainly coarse textures in stratiform zones) have intermediate 34S, although they are mostly dominated by the high 34S component. Rare barite has a homogeneous 34S around +18‰, which is consistent with direct derivation from Lower Carboniferous seawater sulphate. A dual source of sulphide sulphur in the IPB deposits has been considered. A hydrothermal source, derived from reduction of coeval seawater sulphate in the convective systems, is represented by sulphide in the feeder zones. Here variations in 34S are caused by variations in the extent of the sulphate reduction, which governs the SO4:H2S ratio. The second end-member was derived from the bacterial reduction of coeval seawater sulphate at or near the surface, as reflected in the primary textures. A distinct geographical variation in 34S and texture from SW (more bacteriogenic and primary textures) to NE (more hydrothermal textures and 34S) which reflects a variation in the relative input of each source was likely controlled by local geological environments. Given that the sulphur isotope characteristics of the IPB deposits are unlike most VMS and Kuroko deposits, and noting the dominance of a mixed reduced sedimentary and volcanic environment, we suggest that the IPB could represent an ore style which is intermediate between volcanic and sedimentary hosted massive sulphide types . ©1998 Springer-Verlag Berlin Heidelberg
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  • 4
    Publication Date: 1997-12-02
    Description: (translated by E. Pascual) El distrito minero de Aznalcóllar está situado en el extremo sureste de la Faja Pirítica Ibérica (IPB). Muestra rasgos geológicos complejos que pueden ayudar a comprender la geología y la metalogenia de toda la IPB. El distrito abarca varios depósitos minerales con reservas totales de más de 130 Mt de sulfuros masivos. Las leyes medias son de alrededor de 3,6% de Zn, 2% de Pb, 0,4% de Cu y 65 ppm de Ag. También se ha explotado una mineralización de stockwork con una ley de 0,6% de Cu y 30 Mt. Entre los materiales que afloran en el distrito de Aznalcóllar aparecen rocas volcánicas y detríticas de las tres unidades estratigráficas principales descritas en la IPB: grupo de filitas y cuarcitas (PQ), complejo vulcanosedimentario (VSC) y grupo Culm. En el VSC se pueden distinguir dos secuencias. La Secuencia Sur (SS) es principalmente detrítica, y como rasgo peculiar incluye pillow-lavas basálticas y niveles calizos de aguas someras, estas últimas hacia la parte superior de la secuencia. En cambio, la secuencia de Aznalcóllar-Los Frailes (AFS) contiene gran cantidad de rocas volcánicas, relacionadas con los dos principales episodios volcánicos en la IPB. Estos diferentes rasgos estratigráficos indican una distinta evolución paleogeográfica durante el Devónico superior y el Carbonífero inferior. Los sulfuros masivos aparecen asociados a pizarras negras depositadas sobre el primer volcanismo félsico (VA1) Los datos de palinomorfos obtenidos de este horizonte de pizarras negras indican una edad Estruniense para los sulfuros masivos, y en consecuencia una edad devónica superior para el primer ciclo volcánico VA1. Los datos de campo y texturales de las rocas volcánicas sugieren una evolución desde un ambiente de depósito subaéreo (VA1) hasta condiciones hidroclásticas subvolcánicas para el VA2. Esta evolución puede relacionarse con la compartimentación y profundización creciente de la cuenca sedimentaria, tal como lo sugieren también los cambios en los sedimentos asociados, incluidas las pizarras negras y los sulfuros masivos. Pese a los cambios en el tipo de vulcanismo, éste corresponde a una composición de dacítica a riolítica, tanto en las series piroclásticas como en las subvolcánicas. El principal proceso ígneo que controla la variación química de las rocas volcánicas es la cristalización fraccionada de plagioclasa (+accesorios). Este proceso tuvo lugar en reservorios subsuperficiales a poca profundidad, y dio lugar a un rango de composiciones que cubre el rango total de variación de la IPB. La orogenia hercínica produjo una evolución estructural compleja, con una fase mayor de deformación dúctil F1 en la que se produjeron pliegues que evolucionaron a cabalgamientos por laminación del flanco corto. Estos cabalgamientos produjeron repetición tectónica de las mineralizaciones masivas y de stockwork. En Aznalcóllar, parte de la mineralización de stockwork cabalga los sulfuros masivos. Las estructuras anteriores son cortadas por grandes cabalgamientos en régimen frágil y por fallas tardías de desgarre. Los rasgos originales de los depósitos de sulfuros masivos corresponden a mantos extensos con espesores variables (10 a 100 m), asociados sistemáticamente con stockworks. La alteración del muro de los depósitos muestra una zona clorítica interna y otra sericítica periférica. También tienen lugar procesos de silicificación, carbonatización y piritización. La alteración hidrotermal debe considerarse como un proceso multiestadio, que se caracteriza geoquímicamente por enriquecimiento en Fe, Mg y Co e intenso lixiviado de alcalinos y Ca. REE, Zr, Y y Hf también se movilizan en las aureolas cloríticas internas. Tanto en stockworks como en sulfuros masivos se distinguen tres tipos de mineralización, denominadas pirítica, polimetálica y pirítica rica en Cu. Esta última es más común en stockworks, en tanto que la polimetálica predomina en los sulfuros masivos. La zonación de las masas de sulfuros corresponde aproximadamente a un VHMS típico, pero muchas de las zonas alternantes piríticas y polimetálicas están probablemente relacionadas con la tectónica. Aunque la secuencia de cristalización es compleja, se pueden distinguir varias asociaciones minerales, a saber: pirítica framboidal, pirítica de alta temperatura (∼300 °C), pirítica coloforme, polimetálica y una asociación tardía rica en cobre de alta temperatura (350 °C). Los datos de inclusiones fluidas sugieren que los fluidos hidrotermales cambiaron continuamente de temperatura y salinidad, tanto en el tiempo como en el espacio. Las temperaturas y salinidades más altas corresponden a las zonas de stockwork más internas y a los fluidos más tardíos. Un análisis estadístico de poblaciones de las inclusiones fluidas señala tres estadios de actividad hidrotermal, a temperaturas bajas (〈200 °C), intermedias (200–300 °C) y altas (300–400 °C). Los valores de 34S en los sulfuros masivos son inferiores a los de las mineralizaciones de stockwork, lo cual sugiere una actividad bacteriana moderada, favorecida por un ambiente euxínico durante el depósito de las pizarras negras. La íntima relación entre éstas y los sulfuros masivos apunta a un origen de estos últimos por precipitación y reemplazamiento de las pizarras negras, que habrían actuado como barreras, tanto físicas como químicas, durante el depósito de los sulfuros. La actividad hidrotermal comenzó durante el depósito de las pizarras negras, iniciada por un ascenso del gradiente térmico debido al ascenso de magmas básicos. Sugerimos un modelo genético en tres etapas: 1) Circulación difusa de fluidos a baja temperatura, que habría producido lentejones y diseminaciones de pirita interestratificadas con las pizarras negras. Localmente, también se produjo flujo canalizado a mayor temperatura; 2) actividad hidrotermal cíclica, a baja o media temperatura, que produjo la mayor parte de las mineralizaciones piríticas y polimetálicas, y 3) etapa de alta temperatura, que produjo mineralizaciones ricas en cobre con bismuto, sobre todo en la zona de stockwork.The Aznalcóllar mining district is located on the eastern edge of the Iberian Pyrite Belt (IPB) containing complex geologic features that may help to understand the geology and metallogeny of the whole IPB. The district includes several ore deposits with total reserves of up to 130 Mt of massive sulphides. Average grades are approximately 3.6% Zn, 2% Pb, 0.4% Cu and 65 ppm Ag. Mined Cu-rich stockwork mineralizations consist of 30 Mt with an average grade of 0.6% Cu. Outcropping lithologies in the Aznalcóllar district include detrital and volcanic rocks of the three main stratigraphic units identified in the IPB: Phyllite-Quartzite Group (PQ), Volcano-Sedimentary Complex (VSC) and Culm Group. Two sequences can be distinguished within the VSC. The Southern sequence (SS) is mainly detritic and includes unusual features, such as basaltic pillow-lavas and shallow-water limestone levels, the latter located in its uppermost part. In contrast, the Aznalcóllar-Los Frailes sequence (AFS) contains abundant volcanics, related to the two main felsic volcanic episodies in the IPB. These distinct stratigraphic features each show a different palaegeographic evolution during Upper Devonian and Lower Carboniferous. Massive sulphides occur in association with black shales overlying the first felsic volcanic package (VA1) Palynomorph data obtained from this black shale horizon indicate a Strunian age for massive sulphides, and consequently an Upper Devonian age for the VA1 cycle. Field and textural relationships of volcanics suggest an evolution from a subaerial pyroclastic environment (VA1) to hydroclastic subvolcanic conditions for the VA2. This evolution can be related to compartmentalizing and increasing depth of the sedimentary basin, which may also be inferred from changes in the associated sediments, including black shales and massive sulphides. Despite changes in the character of volcanism, the same dacitic to rhyolitic composition is found in both pyroclastic and subvolcanic igneous series. The main igneous process controlling chemical variation of volcanics is fractional crystallization of plagioclase (+accessories). This process took place in shallow, sub-surface reservoirs giving rise to a compositional range of rocks that covers the total variation range of felsic rocks in the IPB. The Hercynian orogeny produced a complex structural evolution with a major, ductile deformation phase (F1), and development of folds that evolved to thrusts by short flank lamination. These thrusts caused tectonic repetition of massive and stockwork orebodies. In Aznalcóllar, some of the stockwork mineralization overthrusts massive sulphides. These structures are cut by large brittle overthrusts and by late wrench faults. The original geometric features of massive sulphide deposits correspond to large blankets with very variable thicknesses (10 to 100 m), systematically associated with stockworks. Footwall rock alteration exhibits a zonation, with an inner chloritic zone and a peripheral sericitic zone. Silicification, sulphidization and carbonatization processes also occur. Hydrothermal alteration is considered a multi-stage process, geochemically characterized by Fe, Mg and Co enrichment and intense leaching of alkalies and Ca. REE, Zr, Y and Hf are also mobilized in the inner chloritic zones. Three ore types occur, both in stockworks and massive sulphides, named pyritic, polymetallic and Cu-pyritic. Of these, Cu-pyritic is more common in stockworks, whereas polymetallic is prevalent in massive sulphides. Zoning of sulphide masses roughly sketches a typical VHMS pattern, but many alternating polymetallic and barren pyritic zones are probably related to tectonics. Although the paragenesis is complex, several successive mineral associations can be distinguished, namely: framboidal pyritic, high-temperature pyritic (300 °C), colloform pyritic, polymetallic and a late, Cu-rich high-temperature association (350 °C). Fluid inclusion data suggest that hydrothermal fluids changed continuously in temperature and salinity, both in time and space. Highest Th and salinities correspond to inner stockworks zones and later fluids. Statistic population analysis of fluid inclusion data points to three stages of hydrothermal activity, at low (〈200 °C), intermediate (200–300 °C) and high temperatures (300–400 °C). 34S values in massive sulphides are lower than in stockwork mineralization suggesting a moderate bacterial activity, favoured by the euxinoid environment prevailing during black shale deposition. The intimate relation between massive sulphides and black shales points to an origin of massive sulphides by precipitation and replacement within black shale sediments. These would have acted both as physical and chemical barriers during sulphide deposition. Hydrothermal activity started during black shale deposition, triggered by a rise in thermal gradient due to the ascent of basic magmas. We suggest a three-stage genetic model: (1) low temperature, diffuse fluid flow, producing pyrite-bearing lenses and disseminations interbedded with black shales; locally, channelized high-T fluid flow occurs; (2) hydrothermal cyclic activity at a low to intermediate temperature, producing most of the pyritic and polymetallic ores, and (3) a late high-temperature phase, yielding Cu-rich and Bi-bearing mineralization, mainly in the stockwork zone. ©1997 Springer-Verlag Berlin Heidelberg
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  • 5
    Publication Date: 1997-12-02
    Description: (translated by E. Pascual) Durante la década pasada, la Faja Pirítica Ibérica (FPI) ha sido un área de actividad minera e investigación cientifica renovadas, lo que ha conducido a la obtención de nuevos datos y conceptos geológicos y metalogénicos, que se exponen sucintamente en este Número Especial. La razón de este interés en la FPI, que forma parte del cinturón orogénico hercínico, es que sus rocas, cuyas edades abarcan desde el Devónico tardío al Carbonífero Medio, albergan una enorme cantidad de mineralizaciones de sulfuros masivos ligados a vulcanismo (1700 millones de toneladas de sulfuros, que totalizan 14,6 Mt de Cu, 13,0 Mt de Pb, 34,9 Mt de Zn, 46100 toneladas de Ag y 880 toneladas de Au). Las mineralizaciones y su entorno muestran signaturas que se pueden relacionar con la mineralogía y la zonación de las masas de sulfuros, con los isótopos de plomo de la mineralización, con las variaciones en los halos de alteración hidrotermal alrededor de las mineralizaciones, con los caracteres geoquímicos de las rocas volcánicas bimodales que albergan los sulfuros masivos, con la compleja evolución tectónica del conjunto durante la orogenia hercínica, con la existencia de paleofallas y estructuras sinsedimentarias que actuaron como canales y trampas de descarga para los fluidos metalíferos y los gossans que se desarrollaron sobre los sulfuros. Se han deducido criterios geológicos discriminantes para cada área de conocimiento, que pueden ser útiles para la exploración minera, complementando las técnicas más tradicionales de prospección. Aunque la cuestión del entorno geodinámico de la FPI todavía es materia de debate, cualquier interpretación tiene que tener ahora en cuenta algunas restricciones incontrovertibles: por ejemplo, los caracteres geoquímicos de una gran parte de las rocas básicas son comparables a los de basaltos derivados del manto y emplazados en entornos tectónicos extensionales, y las rocas ácidas asociadas se produjeron a partir de un protolito cortical básico, a presiones bajas o intermedias y asociadas a un abrupto gradiente térmico. Por consiguiente, la secuencia vulcanosedimentaria que contiene los sulfuros masivos difiere claramente de las series recientes relacionadas con entornos de arco. Consideramos aquí que el entorno tectónico fue extensional y epicontinental y que tuvo lugar durante la convergencia de placas hercínica, que culminó en deformación “thin-skinned” y acreción del terreno constituído por la Zona Sudportuguesa al bloque continental paleozoico ibérico.The Iberian Pyrite Belt (IPB) has, over the past decade, been an area of renewed mining activity and scientific research that has resulted in a wealth of new data and new geological and metallogenic concepts that are succinctly presented in this Thematic Issue. The reason for this interest in the IPB, which forms part of the Hercynian orogenic belt, is that its Late Devonian to Middle Carboniferous rocks host a huge quantity of volcanic-hosted massive sulphide (VMS) mineralization (1700 Mt of sulphides, totalling 14.6 Mt Cu, 13.0 Mt Pb, 34.9 Mt Zn, 46100 t Ag and 880 t Au). The mineralization and its environment display a number of typical signatures that can be related to the mineralogy and zoning of the sulphide orebodies, to the lead isotopes of the mineralization, to the geochemical and mineralogical variations in the hydrothermal alteration halos surrounding the orebodies, to the geochemical characteristics of the bimodal volcanics hosting the VMS, to the complex structural evolution during the Hercynian orogeny, to the presence of palaeofaults and synsedimentary structures that acted as channels and discharge traps for the metalliferous fluids, and to the gossans developed over VMS. Discriminant geological criteria have been deduced for each domain which can be helpful in mineral exploration, complementing the more traditional prospecting techniques. Although the question of the IPB's geodynamic setting is still under debate, any interpretation must now take into account some incontrovertible constraints: for example, the geochemical characteristics of a large part of the basic lavas are comparable to those of mantle-derived basalts emplaced in extensional tectonic settings, and the associated acidic rocks were produced by melting of a basic crustal protolith at low- to medium-pressures and a steep geothermal gradient, thus, the sulphide-bearing volcano-sedimentary sequence differs strongly from recent arc-related series. It is considered here that the tectonic setting was extensional and epicontinental and that it developed during the Hercynian plate convergence, that culminated in thin-skinned deformation and accretion of the South Portuguese terrane to the Iberian Paleozoic continental block. ©1997 Springer-Verlag Berlin Heidelberg
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  • 6
    Publication Date: 1999-07-07
    Description: The Iberian Pyrite Belt, located in the SW Iberian Peninsula, contains many Paleozoic giant and supergiant massive sulphide deposits, including the largest individual massive sulphide bodies on Earth. Total ore reserves exceed 1500 Mt, distributed in eight supergiant deposits (〉100 Mt) and a number of other smaller deposits, commonly with associated stockwork mineralizations and footwall alteration haloes. Massive sulphide bodies largely consist of pyrite, with subordinated sphalerite, galena and chalcopyrite and many other minor phases, although substantial differences occur between individual deposits, both in mineral abundance and spatial distribution. These deposits are considered to be volcanogenic, roughly similar to volcanic-hosted massive sulphides (VHMS). However, our major conclusion is that the Iberian type of massive sulphides must be considered as a VHMS sub-type transitional to SHMS. This work is an assessment of the geological, geochemical and metallogenic data available up to date, including a number of new results. The following points are stressed; (a) ore deposits are located in three main geological sectors, with the southern one containing most of the giant and supergiant orebodies, whereas the northern one has mainly small to intermediate-sized deposits; (b) ore deposits differ one from another both in textures and mineral composition; (c) Co and Bi minerals are typical, especially in stockwork zones; (d) colloidal and other primary depositional textures are common in many localities; (e) a close relation has been found between ore deposits and some characteristic sedimentary horizons, such as black shales. In contrast, relationships between massive sulphides and cherts or jaspers remains unclear; (f) footwall hydrothermal alterations show a rough zoning, the inner alteration haloes being characterized in places by a high Co/Ni ratio, as well as by mobility of Zr, Y and REE; (g) 18O and D values indicate that fluids consist of modified seawater, whereas 34S data strongly suggest the participation of bacterial-reduced sulphur, at least during some stages of the massive sulphide genesis, and (h) lead isotopes suggest a single (or homogeneized) metal source, from both the volcanic piles and the underlying Devonian rocks (PQ Group). It is concluded that, although all these features can be compatible with classical VHMS interpretations, it is necessary to sketch a different model to account for the IPB characteristics. A new proposal is presented, based on an alternative association between massive sulphide deposits and volcanism. We consider that most of the IPB massive orebodies, in particular the giant and supergiant ones, were formed during pauses in volcanic activity, when hydrothermal activity was triggered by the ascent and emplacement of late basic magmas. In these conditions, deposits formed which had magmatic activity as the heat source; however, the depositional environment was not strictly volcanogenic, and many evolutionary stages could have occurred in conditions similar to those in sediment-hosted massive sulphides (SHMS). In addition, the greater thickness of the rock pile affected by hydrothermal circulation would account for the enormous size of many of the deposits. ©1999 Springer-Verlag Berlin Heidelberg
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  • 7
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstracts The determination of trimethoprim in the presence of dyphylline, proxyphylline, theophylline and caffeine by the linear absorbances method is described. Collinear couples of wavelengths, for the interfering dyphylline-proxyphylline-theophylline-caffeine system (in H2SO4, 0.05 mol/L), are provided in order to allow the determination of the analyte in the presence of these interfering substances.
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  • 8
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 70 (1997), S. 3513-3515 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The ordering temperatures Tc1 (disordered β to B2 order) and Tc2 (B2 to L21 order) have been obtained in Cu–Al–Ni shape memory alloys with different concentrations by electrical resistivity. The dependence of the ordering temperatures on the concentration has been established. Also, a modification of the theoretical calculations has been proposed to predict the ordering temperatures in Cu–Al–Ni ternary alloys. A good agreement between the theoretical ordering temperatures and the experimental results has been found. © 1997 American Institute of Physics.
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  • 9
    Publication Date: 1999-11-01
    Print ISSN: 0961-9534
    Electronic ISSN: 1873-2909
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Process Engineering, Biotechnology, Nutrition Technology
    Published by Elsevier
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  • 10
    Publication Date: 2011-06-01
    Print ISSN: 0961-9534
    Electronic ISSN: 1873-2909
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Process Engineering, Biotechnology, Nutrition Technology
    Published by Elsevier
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