Relevant bibliographies by topics / Chrome Spinel

Academic literature on the topic 'Chrome Spinel'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Chrome Spinel"

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Pownceby, M., and P. Bourne. "Detrital chrome-spinel grains in heavy-mineral sand deposits from southeast Africa." Mineralogical Magazine 70, no. 1 (February 2006): 51–64. http://dx.doi.org/10.1180/0026461067010312.

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AbstractDetrital chrome-spinels are contaminant grains within ilmenite concentrates produced from heavy-mineral deposits along the coast of southeast Africa. The presence of even minor levels of chromia in the predominantly ilmenite-rich concentrates, downgrades their market value as potential feedstocks for the production of titania pigment. An understanding of their composition can assist in their removal from the ilmenite concentrates.Compositions from a database of close to 900 chrome-spinel analyses shows the major element components and their ranges (in wt.%) are: Cr: 0.4-45.3, Al: 0.0-31.0, Fe: 8.5-69.6 and Mg: 0.0-12.2. Minor components include Ti: 0.1-11.4 and Zn: 0.0-13.7.The chrome-spinel data fall into two compositionally distinct groups. The first group of spinels is dominated by a strong trend reflecting the mutual substitution between Al3+ and Cr3+ in the spinel structure. The second group of spinels is characterized by compositions containing abundant Fe3O4 magnetite component. The clear division between chrome-spinel compositional types indicates the grains are derived from at least two chemically dissimilar provenances.The compositional differences between the chrome-spinel groups has a positive impact on subsequent ilmenite upgrading treatments as the spinels which contain the highest magnetite component are easily removed via low-intensity magnetic separation procedures.
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Ahmad, S., M. A. Rhamdhani, M. I. Pownceby, and W. J. Bruckard. "Exploratory Study of Separation of Sulphidised Chrome Spinels from Reduced Ilmenite." Minerals 12, no. 10 (September 30, 2022): 1252. http://dx.doi.org/10.3390/min12101252.

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The removal of chromium-containing impurities, such as chrome spinel (ZCr2O4 where Z = Fe, Mg, Mn) from ilmenite (FeTiO3) concentrates through selective sulphidation, has been investigated by the authors. Laboratory experimental studies using sulphur added to ilmenite concentrates under Becher-type reduction conditions showed it is possible to selectively sulphidise chrome spinels from different ilmenite deposits. In this paper, processes to remove the sulphidised chrome spinels from the bulk ilmenite concentrates were investigated using flotation and magnetic separation techniques. Clustering or fusing of the reduced ilmenite (RI) and sulphidised chrome spinel grains was found to have a detrimental effect on flotation performance and made it difficult to have clear separation. A light wet grind was effective for breaking the clustering, but it caused the sulphide rim to spall off from chrome spinel surfaces, which reduces flotation efficiency. The preliminary results obtained after a magnetic separation (0.7 A) of a demetallised sulphidised RI sample show that the sulphidised chrome spinels preferentially report to the magnetic fraction. Additional magnetic separation of the non-magnetic fraction at a lower current (0.3 A) improved the recovery of sulphidised chrome spinels. The demetallisation process followed by a magnetic separation provided insights into a potential route for the removal of chrome spinels from reduced ilmenite concentrates. These two steps simulate the aeration stage of the Becher process. Further studies are required to optimise the process parameters.
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Pownceby, M. "Compositional and textural variation in detrital chrome-spinels from the Murray Basin, southeastern Australia." Mineralogical Magazine 69, no. 2 (April 2005): 191–204. http://dx.doi.org/10.1180/0026461056920246.

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AbstractDetrital chrome-spinels are contaminant grains within heavy-mineral concentrates found in the Murray Basin of southeastern Australia. The presence of even minor levels of chromia in the predominantly ilmenite-rich concentrates downgrades their market value as potential feedstocks for the production of titania pigment.Compositions from a database of close to 5000 chrome-spinel analyses show a broad range in chemistry. The major element components and their ranges (wt.%) are Cr: 3.10–52.06, Al: 0.46–32.50, Fe: 3.50–44.48 and Mg: 0.03–15.79. Minor components include; Ti: 0.01–6.41, Zn: 0.00–23.00 and Mn: 0.00–5.82. The broad variation in composition suggests multiple source areas for the chrome-spinels although detailed textural examination indicates that variation has also been introduced through pre- and post-deposition alteration processes.The Murray Basin chrome-spinel database has the potential to be used in interpreting and predicting the effects of various processing conditions used to separate the chrome-spinels from the ilmenite.
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ALEKSEEV, Aleksandr Valer’evich, and Tat’yana Andreevna SHERENDO. "Composition, structure and magnetic properties of ore chrome spinels of the Klyuchevsky massif (Middle Urals)." NEWS of the Ural State Mining University 1, no. 1 (March 23, 2020): 73–85. http://dx.doi.org/10.21440/2307-2091-2020-1-73-85.

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The overall objective was to create a geological and geophysical field test site for chromite mineralization and detailed works in order to determine and test the main search criteria for disseminated mineralization. To create a field test site, an area was selected in the southern part of the Klyuchevsky massif characterized by abundant development of disseminated mineralization in the banded dunite-clinopyroxenite complex and strong processes of superimposed metamorphism. This paper gives a piece of research on the composition of chrome spinel from disseminated ores that underwent metamorphism of different stages. The composition of chrome spinelide, the evolution of its metamorphism and the related changes in its magnetic properties are examined in detail. It was established that all chrome spinels are of a high-chromium type, to one degree or another, they were subject to secondary changes, leading to the appearance of magnetic phases. The degree and nature of the change in chrome spinels in dunites directly depends on the degree of metamorphism of the rocks. The formation of the magnetic phase begins with the formation of nuclei consisting of single magnetic dipoles, groups of 2-3 dipoles or chains of magnetic dipoles, which was first discovered by us in chrome spinel grains. Then there is an increase in the number of such phases, the appearance of optically diagnosed secondary changes in chrome spinelide. A comparison of the degree of variation of chrome spinel and its reflection in the pattern of recorded anomalies of geomagnetic fields allows us to identify some criteria for the search for disseminated chromite ores of this type.
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Mogessie, A., F. Purtscheller, and R. Tessadri. "Chromite and chrome spinel occurrences from metacarbonates of the Oetztal–Stubai Complex (Northern Tyrol, Austria)." Mineralogical Magazine 52, no. 365 (April 1988): 229–36. http://dx.doi.org/10.1180/minmag.1988.052.365.09.

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AbstractChromite inclusions in uvarovite-chrome garnet, chemically zoned chromite-chrome spinel and chrome spinel-olivine pairs from metacarbonates of the Oetztal-Stubai Complex (northern Tyrol, Austria) are described in terms of their textural occurrences and chemical compositions. Their genetic relationship in relation to the polymetamorphism of the region is discussed.
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SEREBRIANNIKOV, ALEXEI, ALLA LOGVINOVA, and NIKOLAY SOBOLEV. "Specific features of the microimpurity composition of chrome-spinel inclusions in diamonds from kimberlites of Sakha-Yakutia." Domestic geology, no. 6 (January 10, 2023): 50–63. http://dx.doi.org/10.47765/0869-7175-2022-10034.

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Specific features of the microimpurity composition of chrome-spinel inclusions in 323 diamond crystals from eight kimberlite pipes of two diamond-bearing regions of Yakutia were revealed by microprobe analysis. Processed data on their content of the Ni, Zn, V, Mn, and Si impurities are presented. It is shown that chrome-spinels in diamonds from the kimberlite pipes of the different regions are characterized by different contents of the impurity elements. The revealed differences in the composition of chrome spinel inclusions in the diamonds, as well as in the defect-impurity composition of the hosting diamonds, from the different, including neighboring, kimberlite pipes of Yakutia, are evidence of a local heterogeneity in the mantle composition within a certain kimberlite field. These data confirm the opinion of most researchers on heterogeneity of the mantle composition in different regions of the Yakutian diamondiferous province.
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Lodha, Rahul, Carmen Oprea, Tom Troczynski, and George Oprea. "Sintering Studies on Magnesia-Rich Chromium-Free Spinel-Bonded Basic Refractories." Advances in Science and Technology 70 (October 2010): 108–13. http://dx.doi.org/10.4028/www.scientific.net/ast.70.108.

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Basic bricks with Cr2O3 from chrome ore, as the spinel forming oxide, are used in the non-ferrous industry because of their corrosion resistance against fayalite-type slags, rich in FeO. Our objective in this study was to replace Cr3+ with Me4+ ions, which along with Fe3+ could maintain the spinel formation capability with MgO and perform similarly against fayalite slags in non-ferrous furnaces. Our preliminary research studies showed that Cr-free spinels in the MgO-Al2O3-FeOx-Me4+O2 systems could perform against fayalite slags similar to the complex (Mg2+, Fe2+)O·(Cr3+, Fe3+, Al3+)2O3 spinel, the main corrosion resistant component in the magnesia-chrome bricks. The incorporation of iron oxide in the MgO-Al2O3-Me4+O2 systems would contribute to reactive sintering and also in decreasing the solubility of both the ferrous and ferric ions present in the fayalite slag. Phase analysis on stoichiometric mixes showed that the use of tetravalent cation oxides like tin dioxide (SnO2) and titanium dioxide (TiO2) can induce high solubility of spinel in magnesia. In order to maintain charge balance, two trivalent cations were replaced by a tetravalent and a bivalent cation causing the additional bivalent cation to occupy the octahedral position thereby creating an inversion in position of the bivalent ions similar to the behaviour exhibited by Fe3+ occupying tetrahedral site in complex spinel phase of magnesia-chrome ceramics. Most of the magnesia-chrome refractories have ~60 wt. % MgO and hence our experimental mixes contained that amount and called “magnesia-rich” compositions, to be distinguished from the stoichiometric MgAl2O4 spinel. Our findings showed that the incorporation of nano TiO2 powders reduces the temperature of spinel formation as the diffusion path is shortened and thus activates both synthesis and sintering. Compositions containing 60 wt. % magnesia with alumina, nano TiO2 and Fe2O3 fired below 1500°C for 3 hours resulted in complete spinel formation and open porosity less than 5%.
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FAUPL, P., A. PAVLOPOULOS, U. KLÖTZLI, and K. PETRAKAKIS. "On the provenance of mid-Cretaceous turbidites of the Pindos zone (Greece): implications from heavy mineral distribution, detrital zircon ages and chrome spinel chemistry." Geological Magazine 143, no. 3 (April 6, 2006): 329–42. http://dx.doi.org/10.1017/s001675680600197x.

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Two heavy mineral populations characterize the siliciclastic material of the mid-Cretaceous turbidites of the Katafito Formation (‘First Flysch’) of the Pindos zone: a stable, zircon-rich group and an ophiolite-derived, chrome spinel-rich one. U/Pb and Pb/Pb dating on magmatic zircons from the stable heavy mineral group clearly illustrate the existence of Variscan magmatic complexes in the source terrain, but also provide evidence for magmatism as old as Precambrian. Based on microprobe analyses, the chrome spinel detritus was predominantly supplied from peridotites of mid-ocean ridge as well as suprasubduction zone origin. A small volcanic spinel population was mainly derived from MORB and back-arc basin basalts. The lithological variability of the mid-Cretaceous ophiolite bodies, based on spinel chemistry, is much broader than that of ophiolite complexes presently exposed in the Hellenides. The chrome spinel detritus compares closely with that from the Outer and Inner Dinarides. The source terrain of the ophiolite-derived heavy minerals was situated in a more internal palaeogeographic position than that of the Pindos zone. The zircon-rich heavy mineral group could have had either an external and/or an internal source, but the chrome spinel constantly accompanying the stable mineral detritus seems to be more indicative of an internal source terrain.
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Sherendo, Tatyana, Valentin Mitrofanov, Aleksey Vdovin, Petr Martyshko, Aleksey Alexeev, Dmitry Zamyatin, Vladimir Vazhenin, and Lidia Pamyatnykh. "Magnetic Clusters in Natural Ferro-Chromian Spinels." Solid State Phenomena 233-234 (July 2015): 587–90. http://dx.doi.org/10.4028/www.scientific.net/ssp.233-234.587.

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The results of investigations of natural iron-chromium spinels of variable composition Fe2+(Cr2-xFex3+)O4 of the chromite-bearing Klyuchevskoi massif (Middle Urals), which are the main carriers of the magnetization of rocks are presented. Substantial changes in the composition and in magnetic structure of accessory chrome-spinels scattered in the host rock are established, unlike the almost unaltered ore-forming chrome-spinels, under the influence of secondary geological processes. To establish the connection between the chrome-spinel changes at the microlevel and features of the geomagnetic field anomalies created by this carrier of magnetization of rocks, it is carried out a complex of investigations of Fe-Cr-spinels (thermomagnetic analysis over the temperature range (4÷1000) K; magnetic resonance (MR) spectroscopy and magnetic force microscopy (MFM) in addition to magnetomineralogical studies). As a result, in the relict areas of grains of the accessory chrome-spinels were first discovered the magnetic clusters (superparamagnetic phases) in the form of single or groups of 2 – 3 magnetic dipoles of tens nanometers in size, or in the form of chain-like structures of magnetic dipoles/single domains.
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BLADES, MORGAN L., JOHN FODEN, ALAN S. COLLINS, TADESSE ALEMU, and GIRMA WOLDETINSAE. "The origin of the ultramafic rocks of the Tulu Dimtu Belt, western Ethiopia – do they represent remnants of the Mozambique Ocean?" Geological Magazine 156, no. 1 (October 30, 2017): 62–82. http://dx.doi.org/10.1017/s0016756817000802.

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AbstractThe East African Orogen contains a series of high-strain zones that formed as Gondwana amalgamated. The Tulu Dimtu shear belt is one of these N–S structures within the Barka–Tulu Dimtu zone in western Ethiopia, and contains ultramafic bodies of equivocal origin. Identifying the petrogenetic origin of these enigmatic rocks provides evidence for the geodynamic significance of these shear zones. Owing to their altered state, these ultramafic rocks’ well-preserved chrome spinels provide the only reliable evidence for their source and tectonic affiliation. Chrome spinels have high Cr2O3 (30.04–68.76 wt %), while recalculated Fe2O3 (< 2 %) and TiO2 (0.01–0.51 %) values are low. The Cr# (molar Cr3+/Cr3+ + Al2+) and Mg# (Mg2+/Mg2+ + Fe2+) have averages of 0.88 and 0.22, respectively. Based on olivine–spinel equilibria, the calculated fO2 values (FMQ +3.03) for the dunites reveal a highly oxidized environment. This spinel chemistry (high Cr# > 0.6 and low Ti) supports a supra-subduction origin, with an oxidized mantle source more refractory than depleted MORB mantle (DMM). These spinel compositions indicate that some ultramafic bodies in western Ethiopia, including those from Daleti, Tulu and Dimtu, are serpentinized peridotites emplaced as obducted ophiolite complexes. By contrast, the ultramafic rocks from the Yubdo locality have a different spinel chemistry, with strong affiliation with igneous spinels formed in Alaskan-style mafic intrusions. These collective results suggest that regardless of their origin as supra-subduction ophiolites or as Alaskan-type intrusions, these spinels were formed on a convergent-subduction margin.
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Dissertations / Theses on the topic "Chrome Spinel"

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Dare, Sarah Anne Sophia. "Chrome-spinel geochemistry of the northern Oman-United Arab Emirates ophiolite." Thesis, Cardiff University, 2007. http://orca.cf.ac.uk/54747/.

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The Oman ophiolite is the largest and best preserved ophiolite in the world and records a switch from mid-ocean ridge (MOR) to supra-subduction zone (SSZ) setting. This study investigates the geochemical variability of chrome-spinel in the mantle sequence of the poorly known United Arab Emirates (U.A.E.) part of the northern Oman-U.A.E. ophiolite. Extensive field work was carried out and 260 samples collected for petrogenetic studies and geochemical mapping of the U.A.E. mantle. Chrome-spinel geochemistry provides valuable information on bom the residual mantle and on the nature and extent of melt-rock reaction. In particular, it is used to fingerprint the compositions of the magmas that interacted with the mantle lithosphere. This study also develops a new method to analyse gallium in chrome-spinel by Laser Ablation-ICP-MS, and successfully uses it to improve the tectonic discrimination of chrome-spinel. The results show that the U.A.E. mantle lithosphere formed at a MOR-type setting and was modified by melt-rock reaction with MORB-type and SSZ-type melts. This history of melt infiltration strongly resembles the magmatic history of the crustal sequence in each of the Aswad and Khawr Fakkan Blocks. Geochemical mapping illustrates a strong spatial control on the pattern of melt infiltration in the mantle and constrains the proximity of each mantle domain with respect to the subduction zone. The Khawr Fakkan mantle extensively interacted with boninitic melts during subduction initiation. Thus, it was closer to the subduction zone than the Aswad mantle which predominantly interacted with island-arc tholeiite melts. Importantly, this work demonstrates for the first time that the Dibba Zone peridotites originate from pre-existing 'true' MOR mantle lithosphere between the trench and the main body of the ophiolite. A further important conclusion is that the mantle lithosphere of the northern Oman-U.A.E. ophiolite was not the source region for the SSZ magmatism. Previous workers proposed that the plane of detachment and the subduction zone were the same, which implies that the mantle of the ophiolite was the source of the SSZ magmatism. Instead, this study proposes that detachment of the ophiolite took place at a shallower level than the plane of the subduction zone and thus provides strong evidence for a subduction zone at a still deeper level. During detachment, the ophiolite incorporated slices of ultramafic rock near the trench (i.e. the Dibba Zone peridotites) as it bulldozed its way over the underlying plate and onto the continental margin of Arabia.
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Tabit, Adelhalim. "Equilibre orthopyroxene-spinelle : etude experimentale et theorique, application aux roches issues du manteau superieur." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21025.

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Le travail concerne l'equilibre orthopyroxene-spinelle dans les lherzolites a spinelle, roches caracteristiques du manteau superieur. L'etude mineralogique d'echantillons naturels montre que les teneurs en aluminium et en chrome dans l'orthopyroxene varient avec la texture de l'echantillon, la composition globale du systeme et les conditions de temperature controlant les phases de deformation cristallisation. Le comportement des elements di- et triavalents dans l'equilibre orthopyroxene-spinelle peut etre utilise a des fins geovelocimetriques. Les resultats obtenus lors de l'etude experimentale du systeme simplifie cr::(2)o::(3)-mgo-al::(2)o::(3)-sio::(2) ont fait l'objet d'un traitement mathematique par methode d'inversion generalisee. On obtient ainsi une equation geothermometrique applicable aux roches ultrabasiques du facies lherzolite a spinelle: t4(k)=(61490-16000(y::(crsp))**(2))/(27-8,314lnkd)
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Cornu, Lucile. "Matériaux X-Chromo-luminescents de type spinelle et elpasolite : relation structure-propriétés." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0082/document.

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Les matériaux luminescents sensibles à la température ou l’exposition auxrayons ultra-violets sont de plus en plus recherchés. Dans ces travaux, deux famillesde composés ont été synthétisés et caractérisés.La première famille est celle des composés ZnAl2O4 dopés aux ionsmanganèse de structure spinelle. Ces composés présentent des propriétés dethermo-chromo-luminescence irréversible avec une variation d’émission du rouge auvert en fonction de l’histoire thermique subie par le matériau. Ici les variations delongueurs d’onde d’émission sont dues au changement de l’environnement des ionsluminescents manganèse en fonction de la température. Il a été démontré que lagamme de température de commutation peut être modulée par une variation de lacomposition de la matrice hôte. La seconde famille est celle des elpasolites decomposition Rb2KInF6 dopé au cérium. Ces composés présentent des propriétés dephoto-chromo-luminescence réversible par oxydo-réduction entre les ions cérium etindium. Sous irradiation UV, il est possible de créer des espèces (In+) quiluminescent dans le rouge. Nous avons montré que le retour aux propriétés initialespeut avoir lieu sous irradiation UV à plus hautes longueurs d’onde ou par chauffage.La spécificité du phénomène associé à cette structure et cette compositionparticulière peut s’expliquer par des considérations structurales, la situation spatialedes ions cérium et indium permettant des échanges électroniques par recouvrementorbitalaire de ces deux ions
Research for luminescent materials sensitive to temperature or UV exposurevariation are increasing. Here we manage to synthesized and characterized materialswhich show such properties.First, spinel structure materials as ZnAl2O4 doped with manganesecompounds exhibit irreversible thermo-chromo-luminescence properties. Thismaterial shows a variation of emission wavelength from red to green with a variationof the thermal history of the sample. These variations are due to a modification of themanganese environment in the structure with the temperature. It was demonstratedthat the temperature range of the luminescence switch can be tuned by themodification of the matrix composition. Secondly, cerium-doped Rb2KInF6compounds with elpasolite structure exhibit reversible photo-chromo-luminescenceproperties. Under UV irradiation, new luminescent species (In+), created by redoxreaction between Ce3+ and In3+ species, and which emits in the red range, can beproduced. We demonstrate the reversibility of the phenomenon by UV irradiation orafter a thermal treatment. The specificity of these properties with this structure andthis composition can be explained by structural consideration: Ce3+ and In3+positioning in the cell allowing electronic exchanges between these ions thanks toorbital overlap
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BENOIT, VINCENT. "Etat d'equilibre de peridotites du manteau superieur : application au plateau du colorado." Paris 7, 1987. http://www.theses.fr/1987PA077186.

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Deux nouvelles calibrations de methodes thermobarometriques a partir de donnees experimentales. La premiere basee sur la solubilite de diopside entre clinopyroxene et orthopyroxene. Elle prend en compte l'effet d'elements mineurs tels que na et fe. Ce thermobarometre, combine avec le thermometre base sur la solubilite de l'enstatite dans les deux pyroxenes fournit un bon outil pour tester l'etat d'equilibre des peridotites a spinelle. La deuxieme calibration est basee sur la solubilite du chrome dans la spinelle et le grenat coexistants
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Verger, Louisiane. "Les oxydes de chrome dans les pigments et les décors de porcelaine." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066546/document.

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Les oxydes de chrome permettent d’obtenir une large variété de couleurs, conduisant à leur utilisation répandue dans les arts céramiques. À la manufacture de Sèvres, leurs propriétés colorantes ont été explorées dès la découverte du chrome à la fin du 18ème siècle. Les travaux initiés par Brongniart ont conduit à une série de 76 pigments pour porcelaine composés d’oxydes de chrome, régulièrement synthétisés au laboratoire de la manufacture. Nous avons mené une étude exhaustive de ces pigments, permettant une classification basée sur leur analyse minéralogique et mettant en évidence le rôle du Cr3+ dans ces pigments, avec l’absence de Cr6+. Le mélange de ces pigments avec un composant incolore est appliqué sur la porcelaine, et porté à haute température afin d’obtenir un émail, c’est-à-dire une couche décorative partiellement vitreuse à la surface de la porcelaine. Les pigments composés de chrome se retrouvent dans les décors verts, roses, bleu-vert, marron et noirs. Après avoir caractérisé la spéciation et l’environnement du chrome dans l’ensemble de ces pigments, cette thèse s’est concentrée sur un pigment particulier, majoritairement composé de gahnite au chrome ZnAl2O4:Cr3+. Ce type de pigment a été identifié dans une série d’œuvres produites par la manufacture, entre la fin du 19ème et le début du 20ème siècle, correspondant à la période de l’art nouveau. La solution solide complète ZnAl2-xCrxO4 a été étudiée afin de préciser l’environnement structural du chrome, montrant l’importance des seconds voisins Cr dans les variations de couleur. Au cours de la cuisson de l’émail, un mécanisme de dissolution progressive des grains de pigments a été mis en évidence, résultant de l’interaction avec le composant incolore en cours de vitrification. Notre travail montre la faible solubilité du Cr dans le verre et sa spéciation préférentielle dans les cristaux, entrainant parfois des changements de phases ou des modifications de composition le long de solutions solides lors du traitement thermique à haute température. Ces modifications ont permis de mieux comprendre l’origine de la couleur dans les décors de porcelaine ainsi que les mécanismes de formation des émaux
Chromium oxides are widely used in the ceramic industry because they are characterized by a large variety of colors. At the French porcelain manufacture of Sèvres, their coloring properties have been explored since the discovery of chromium at the end of the 18th century. The researches initiated by Brongniart lead to a group of 76 pigments for porcelain composed of chromium oxides, regularly synthesized at the laboratory of the manufacture. An exhaustive study was done on these pigments, which enables to propose a classification based on their mineralogical analysis and highlights the role of Cr3+ in the color of the pigments, without Cr6+. The mixture of one or two pigments and an uncolored frit is applied on the porcelain, and fired at high temperature to obtain a glaze, i.e. a partly glassy decorative layer on the top of the porcelain. Pigments composed of chromium are used to obtain green, pink, greenish-blue, brown and black glazes. This thesis focuses on a particular pigment, mainly composed of gahnite doped with chromium ZnAl2O4:Cr3+. This kind of pigment was identified in a collection of artefacts produced by the manufacture between the end of the 19th century and the beginning of the 20th century. This period corresponds to the artistic movement Art Nouveau. The solid solution ZnAl2-xCrxO4 was studied to get the structural environment of Cr, showing the role of the second neighbor Cr in the color variation. During firing of the glaze, a mechanism of gradual dissolution of the initial grains of pigments was determined, resulting of reactions with the uncolored frit. Our work shows the low solubility of Cr in glass and its preferential speciation in crystals, leading to crystalline phase changes or modifications of composition along solid solutions during the thermal treatment at high temperature. These modifications enable to understand the origin of color in porcelain glazes and the mechanism of glaze formation
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Juhin, Amélie. "Propriétés électroniques et structurales du chrome en impureté dans les cristaux : approche expérimentale et théorique." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2008. http://tel.archives-ouvertes.fr/tel-00340612.

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Cette thèse a pour but d'étudier l'environnement électronique et structural du chrome en substitution de l'aluminium dans des cristaux isolants cubiques, et de discuter son influence sur la variation du champ cristallin. Nous avons combiné des spectroscopies sélectives du chrome (EXAFS et XANES au seuil K), une approche ab initio (calculs de minimisation d'énergie et de spectres XANES) et une approche multiélectronique (simulation du dichroïsme linéaire naturel des rayons X). Des développements théoriques ont été effectués puis appliqués au cas de la section efficace d'absorption X, afin d'extraire les propriétés spectroscopiques d'un site individuel à partir de celles du cristal cubique.

L'environnement structural relaxé autour du Cr a été déterminé pour le spinelle MgAl2O4:Cr3+ (rouge) et pour les grenats pyrope Mg3Al2Si3O12:Cr3+ (rouge) et grossulaire Ca3Al2Si3O12:Cr3+ (vert). La sphère de coordination du Cr est voisine de celle observée dans le pôle pur chromifère correspondant (MgCr2O4, Mg3Cr2Si3O12 et Ca3Cr2Si3O12, respectivement), du point de vue des distances interatomiques et de la symétrie locale. La variation de la distance moyenne Cr-O joue un rôle important dans celle du champ cristallin, mais ne permet pas d'expliquer à elle seule l'évolution du celui-ci au sein des solutions solides, entre les cristaux dilués et entre les cristaux concentrés. Nous montrons que la nature de la liaison Cr-O est un facteur important et que l'environnement à moyenne distance autour du chrome exerce une influence sur ses propriétés spectroscopiques. En particulier, les deuxièmes voisins ont un effet privilégié sur la distance Cr-O et la nature de cette liaison.
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Bizi, Mohamed. "Propriétés optiques d'ions de métaux de transition (3D3 à 3D8) dans les oxydes spinelles et de verres sodocalciques." Rouen, 1989. http://www.theses.fr/1989ROUES035.

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L'objet de cette thèse est l'étude des propriétés optiques des ions de métaux de transition (3D3 à 3D7) dans les deux coordinations de la structure spinelle. L'interprétation par la méthode du champ cristallin permet d'identifier: les transitions D-D, les bandes de transferts de charges du ligand vers le métal (LMCT), les transitions de paires (intensifiées par le couplage magnétique). L'analogie Z+1 explique la structure du prépic des spectres d'absorption X au niveau de la discontinuité K du Fe(iii) et Mn(ii) dans les deux environnements qui peut être corrélée avec les données de la spectroscopie optique. Un modèle directement issu de données de la spectroscopie optique est plus approprié pour rendre compte de la structure 3D3 (Mn4+, Cr3+) en environnement octaédrique. Les études de verres sodocalciques en spectrométrie Mössbauer et spectrométrie optique montrent que le fer(ii) et le fer (iii) se situent en environnement tetraédrique et octaédrique. Les paramètres optiques (Dq et b) des principaux colorants dans ces verres sont identiques à ceux des oxydes simples et des oxydes mixtes de structure spinelle
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Martinelli, Laure. "Mécanisme de corrosion de l' acier T91 par l' eutectique Pb-Bi utilisé comme matériau de cible de spallation : importance pour les réacteurs hybrides." Paris 6, 2005. http://www.theses.fr/2005PA066442.

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Blades, Morgan. "The age and origin of the western Ethiopian Shield." Thesis, 2013. http://hdl.handle.net/2440/83744.

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Western Ethiopia is made up of a range of supra-crustal and plutonic rocks. The Precambrian exposures of the Western Ethiopian Shield are positioned within the juvenile Neoproterozoic crust of the Arabian Nubian Shield and the older, predominately gneissic Mozambique Belt (Woldemichael et al. 2010). The age and origin of the Western Ethiopian Shield are still largely unidentified. The aim of this paper is to constrain the age and origin of the sedimentary and igneous rocks within the Western Ethiopian Shield. This will be done using isotopic techniques. The detrital zircons have been analysed for U-Pb age (yielding maximum depositional ages and age provenance information) and Hf isotopes (to investigate the nature of zircons). Geochemical analysis on the Thermal Ionisation Mass Spectrometer (TIMS), Inductively Coupled Plasma Mass Spectromentry (ICP-MS) and microprobe has also been undertaken. One of the focuses is the examination of the volcanic and volcaniclastic successions, as well as, the geochemical nature of the ultra-mafic bodies in the Shield. The geochemistry of metavolcanic and meta-volcaniclastic data suggest that the origin of the volcanics formed in an arc-like setting. Relatively low niobium; however, suggest that the mantle source may have been more enriched than that seen in modern volcanic arcs. Detrital zircons, obtained from a meta-sandstone, yielded provenance age peaks at ~2499 Ma, ~1855 Ma and between 1100-800 Ma and a maximum depositional age of 838 ± 13 Ma. Hf Isotopes from the same zircons demonstrated that both the oldest and youngest populations have broadly juvenile Hf isotopic values however; ~1820 Ma age shows significantly evolved Hf isotopic values. A minimum age constraint on the deformation was provided by the U-Pb age of 572 .6 ± 7.6 Ma and yielded whole epsilon Nd values of 3.74 and epsilon Hf values of 6.79-7.98, demonstrating a juvenile origin. A significant aspect of the Arabian-Nubian Shield is the interpretation of the N-S oriented regional shear zones. Concentrically zoned mafic/ultramafic bodies, previously identified as remnants of the oceanic crust, are suggested to be Alaskan-type intrusions. Though chemically different to typical Alaskan-type intrusions these display a subduction affinity and have close associations to shear-zone hosted intrusions elsewhere in the Arabian Nubian Shield. Thus, they have been interpreted as being formed in similar supra subduction intrusive settings.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Earth and Environmental Sciences, 2013
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Kessel, Ronit. "The Activity of Chromite in Multicomponent Spinels : An Experimental Study with Implications for the Metamorphic History of Equilibrated Ordinary Chondrites." Thesis, 2002. https://thesis.library.caltech.edu/6827/1/Kessel_r_2002.pdf.

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An experimental technique for evaluating the activity of chromite in multicomponent spinels was developed by equilibrating the spinel of interest with a Pt-alloy under a controlled temperature and oxygen fugacity. The thermodynamic properties of the ternary Pt-Fe-Cr system was evaluated, such that activities of Cr and Fe in an equilibrated Pt-alloy can be used to calculate the activity of chromite in the spinel of interest.

The ternary activity model formulation used is based on the characterization of each bounding binary system, Pt-Fe, Pt-Cr, Fe-Cr, with the addition of ternary interaction terms. The Pt-Fe and Pt-Cr systems are described as asymmetric regular solutions with interaction parameters of W_(PtFe)=-138.0±3.3, W_(FePt)=-90.8±24.0, and W_(PtCr)=-129.1±1.2, W_(CrPt)=-80.9±4.4, and D_(PtCr)=+94.4±2.5 kJ/mol (1σ), respectively. Combined with literature thermodynamic properties for the Fe-Cr system, the ternary interaction parameters in the Pt-Fe-Cr system were found to be C_(Cr)=0, C_(Pt)=+ll5.7, and C_(Fe)=-68.6 kJ/mol.

Using this technique, the metamorphic history of equilibrated ordinary chondrites was evaluated by examining the compositions and textures of olivines, pyroxenes, spinels, and alloys. Equilibrium temperatures based on Fe-Mg exchange between olivine and spinel exhibit a range of 680-796°C in H, L, and LL ordinary chondrites spanning petrographic type 4 to 6. Type 4 chondrites in all groups record variable temperatures that are lower than or equal to those of types 5 and 6 chondrites, implying decoupling of metamorphic temperature from petrographic type. Cooling rates near 800°C were found to be 1-3 K/Ma, slow enough to allow continous re-equilibration of spinel grains from peak metamorphic temperatures to the olivine-spinel equilibration temperature.

The temperature-oxygen fugacity relationships in equilibrated H chondrites were constrained from spinel-alloy and olivine-pyroxene-alloy phase assemblages based on the mineral compositions and activity-composition models. Log_(10)f_(02) values based on the assemblage olivine-pyroxene-alloy are -1.75±0.02 log units below Iron-Wüstite (IW) buffer, regardless of petrographic type. The log_(10)f_(02) values calculated based on the spinel-alloy coexistence are at least ~1.5 log units more oxidizing than those based on the olivine-pyroxene-alloy if olivine-spinel equilibration temperatures (728-820°C) are assumed. This probably indicates that closure for spinel-alloy equilibria occurred under retrograde conditions at temperatures below 700°C.

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Books on the topic "Chrome Spinel"

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Roberts, William S. Bulk mineralogy and geochemistry of selected Alaskan chromian spinel samples. Pittsburgh, Pa: U.S. Dept. of the Interior, Bureau of Mines, 1985.

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Book chapters on the topic "Chrome Spinel"

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Baumgartner, Peter O. "Chrome Spinel and Clay Mineralogy." In Jurassic Sedimentary Evolution and Nappe Emplacement in the Argolis Peninsula (Peloponnesus, Greece), 97–100. Basel: Birkhäuser Basel, 1985. http://dx.doi.org/10.1007/978-3-0348-9319-0_7.

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Meng, Jinxia, Weiqing Chen, Jizeng Zhao, and Li Liu. "Study of the Synthesis of MgAl2O4 Spinel Refractory from Waste Chromium Slag of a Chrome Plant in China." In Energy Technology 2018, 341–55. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-72362-4_30.

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Kislov, Evgeniy V., Vadim S. Kamenetsky, Alexey V. Malyshev, and Vladislav V. Vanteev. "Concentrically-Zoned Mafic-Ultramafic Marinkin Massif, Middle Vitim Highland, Baikal Region, Russia: Inclusions in Chrome Spinel—Key to Mineral Formation Processes." In Springer Proceedings in Earth and Environmental Sciences, 111–18. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-49468-1_15.

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Barman, Junmoni, and S. Ravi. "Tunable Exchange Bias Behavior Near Room Temperature in Spinel Chromite." In Proceedings of 28th National Conference on Condensed Matter Physics, 49–56. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-5407-7_6.

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Martin, Ellinor, Birger Schmitz, Fredrik Terfelt, Luis Erick Aguirre-Palafox, and Walter Alvarez. "The micrometeorite flux in the Albian–Aptian age (ca. 103–117 Ma): A search for Tycho ejecta in pelagic sediments using chrome spinels." In From the Guajira Desert to the Apennines, and from Mediterranean Microplates to the Mexican Killer Asteroid: Honoring the Career of Walter Alvarez. Geological Society of America, 2022. http://dx.doi.org/10.1130/2022.2557(23).

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ABSTRACT Numerical models of meteorite delivery from impacts on the Moon have demonstrated that the impact event forming the lunar crater Tycho (~85 km diameter; ca. 109 Ma age) would have delivered considerable amounts of ejected material to Earth. The ejecta, containing lunar Ti- and V-rich chrome spinels, would have been distributed globally and admixed with seafloor sediments over a few meters of a typical marine stratigraphic interval. In order to locate such ejecta, samples weighing ~12–25 kg each, with one-meter spacing were extracted over an ~30 m interval of the deep-sea formed Calera Limestone, Albian and Aptian age (ca. 103–117 Ma), from the Pacifica Quarry, south of San Francisco. The limestone samples were leached in acids and residues searched for possible lunar Ti-rich chrome-spinel grains. In a total of 689 kg of limestone, 1154 chrome-spinel grains were found. Of these, 319 contain &gt;0.45 wt% V2O3, of which 227 originate from equilibrated ordinary chondrites. The majority of the other 92 grains with &gt;0.45 wt% V2O3 are most likely from different types of achondritic meteorites. Among these, we found eleven particularly Ti-rich chrome-spinel grains. The elemental abundances of these grains were compared with chrome spinel from lunar, howardite-eucrite-diogenite (HED) and R-chondritic meteorites. This showed that only one of these grains could potentially be of lunar origin. The bulk of the other grains likely originate from HED meteorites based on oxygen isotopic analysis of similar grains in previous studies. Grains with TiO2 &gt;10 wt%, common among lunar spinels are not found, further supporting an HED source for the Ti-rich grains. In summary, Albian and Aptian strata in the Pacifica quarry do not likely record any major lunar impact event. Either the timing of the impact is located within a ca. 110–114 Ma unconformity in the middle part of the section or the impact is likely older than the interval searched.
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Schmitz, Birger, Martin Schmieder, Shiyong Liao, Ellinor Martin, and Fredrik Terfelt. "Impact-crater ages and micrometeorite paleofluxes compared: Evidence for the importance of ordinary chondrites in the flux of meteorites and asteroids to Earth over the past 500 million years." In From the Guajira Desert to the Apennines, and from Mediterranean Microplates to the Mexican Killer Asteroid: Honoring the Career of Walter Alvarez. Geological Society of America, 2022. http://dx.doi.org/10.1130/2022.2557(18).

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ABSTRACT Although the ~200 impact craters known on Earth represent only a small fraction of the craters originally formed, the available data suggest an excess of craters by one order of magnitude, in number, in the interval ca. 470–440 Ma during the Ordovician. Most of these “excess” craters may be related to the breakup of the L-chondrite parent body (LCPB) in the asteroid belt at 465.8 ± 0.3 Ma. This is the only obvious peak in the crater-age record that can currently be attributed to an asteroid breakup and shower event. Spatial crater densities in regions with high potential for crater preservation (e.g., Canada and Scandinavia) support a one order-of-magnitude increase in the flux of large (&gt;0.1 km) impactors following the LCPB breakup. A similar pattern as seen in the cratering record is emerging in studies of the flux of micrometeoritic chrome spinel through the Phanerozoic, with so far only one major spike in the flux, and associated with the LCPB breakup. Similarly, the record of K-Ar and (U-Th)/He gas retention ages of recently fallen meteorites only locates one major breakup, the LCPB event, during the Phanerozoic. On the other hand, astronomical backtracking studies of the orbits of asteroid family members indicate ~70 major family-forming breakups within the past ~540 m.y., which apparently have not left any clear imprint in Earth’s geological record. The chrome-spinel grains recovered in our studies dominantly represent large micrometeorites (&gt;300 µm) and as such are also representative of the flux of larger meteorites to Earth. An observed, nearly constant flux of ordinary chondritic chrome-spinel grains throughout the Phanerozoic, except after the LCPB event, indicates that the present situation—with a clear dominance of ordinary chondritic matter in the large (&gt;500 µm) micrometeorite and macroscopic meteorite fractions—has prevailed at least for the last 500 m.y. This is also supported by generally high ratios in our samples of chrome-spinel grains from ordinary chondrites compared to other types of spinel-bearing meteorites. The chrome-spinel data together with the abundance of fossil meteorites (1–21 cm in diameter) on the Ordovician seafloor also sets an upper limit at one order of magnitude on the increase in flux of large (&gt;0.1-km-diameter) L-chondritic projectiles to Earth following the LCPB. Such an increase would not stand out in the global cratering record if ordinary chondritic impactors had only represented a small fraction of all Phanerozoic impactors. We argue that the origin of impactors delivered to Earth during the past 500 m.y. has mirrored the flux of large micrometeorites and meteorites, with ordinary chondrites being an important or, most likely, the dominant (in numbers) component throughout.
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"Chrome-spinels." In Rare Earth Elements in Ultramafic and Mafic Rocks and their Minerals, 89–100. CRC Press, 2012. http://dx.doi.org/10.1201/b11831-3.

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"Chrome-spinels." In Rare Earth Elements in Ultramafic and Mafic Rocks and their Minerals, 99–110. CRC Press, 2012. http://dx.doi.org/10.1201/b11831-5.

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"Distribution of chrome-spinel grains across the 3He anomaly of the Tortonian Stage at the Monte dei Corvi section, Italy." In 250 Million Years of Earth History in Central Italy: Celebrating 25 Years of the Geological Observatory of Coldigioco, 383–91. Geological Society of America, 2019. http://dx.doi.org/10.1130/2019.2542(21).

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Sa\'ad ZA Kader, Al-Mashaikie. "Abnormal Ophiolite (Olivine/Pyroxene Rich) Sandstone NE Iraq: An Approach to the Origin and Tectonosedimentary Evolution of Zagros Foreland Basin." In New Insights in Sedimentary Rocks [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.108333.

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Unusual Paleocene ophiolite sandstone rich in olivine/pyroxene identified in Zagros Thrust Belt (NZTB) in NE Iraq. NZTB is regionally extended from Iran to Alpen Belt. Kolosh sandstones are controlled by progressive thrusting during late Cretaceous-Paleocene. Zagros thrust sheets composed of ophiolites, oceanic crust, basaltic flows, and ash sequences. Kolosh sandstones reveal high percentages of fresh olivine-pyroxene grains accompanied by igneous intrusive and volcanic ultrabasic-basic fragments, which are reported for the first time in NE Iraq and along ZTB. Olivine, pyroxene, ultrabasic igneous altered, serpentine and chlorite fragments, heavy minerals (includes chrome spinal), anorthite, and labradorite all together composed about 70% of the mineralogical composition. Sanidine, anorthoclase, quartz and cristobalite, argillaceous, carbonate and chert fragments all together composed (12.25%), supported by argillaceous matrix (16.53%), which are derived from mantle and oceanic crust/ophiolite sequences from NE Iraq, emplaced during late Cretaceous with arc volcanism, which subjected to rapid submarine erosion and deposition. Intense wave action accelerated the erosion of beach rocks, and concentrate the heavy minerals insitue that slumped to deeper margins. Identified lithofacies types, grouped in four associations, slope/submarine channel, inner, outer fan, and hemipelagic/pelagic, respectively, represented progressive upward transgression from slope to basin plain systems controlled by progressive thrusting.
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Conference papers on the topic "Chrome Spinel"

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Tan, Taide, and Yitung Chen. "Formation and Protection of Fe-Cr Oxide Spinel During the Oxidation Process of Stainless Steels in LBE Environment." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12899.

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The formation of the spinel of magnetite and chrome oxide, is a very complex process, especially with the scale removal effect in flowing lead bismuth eutectic (LBE) nuclear coolant. This paper studied the formation and the protection of the spinel of magnetite and chrome oxide on stainless steel, in different environments at a mesoscopic level. The role of the alloying element has been analyzed. The formation of the spinel of magnetite and chrome oxide and the scale removal effect are simulated using a stochastic cellular automaton method. The protection of this spinel layer to the structural materials has been analyzed.
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O’Toole, Stephen, and Nicholas Stevens. "High Temperature Diffusion of Oxygen in Chromite." In ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/pvp2006-icpvt-11-93582.

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Molecular dynamics was used to calculate the diffusion coefficient of oxygen over a temperature range of 900–1700K. The chromite (FeCr2O4) system used consisted of 448 ions in a spinel structure. The spinel consisted of Fe2+ in tetrahedral sites and Cr3+ ions in octahedral sites surrounded by O2− ions. Schottky defects were made in the system by removing 10 oxygen ions, 4 iron ions and 4 chromium ions. The trajectory files from the simulations were examined for oxygen movement via a vacancy hopping mechanism and the mean-squared displacement of oxygen was plotted against time. A linear fit was performed to the plots and Einstein’s relationship was used to derive the diffusion coefficient from the gradient. The diffusion coefficients were then plotted against temperature and an Arrhenius expression was fitted to the trend and compared with the experimental trend calculated by Takada & Adachi.
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Grimbergen, Michael, D. G. Nest, Keven Yu, T. Y. B. Leung, Madhavi Chandrachood, Alan Ouye, Saravjeet Singh, Ibrahim Ibrahim, Ajay Kumar, and David Graves. "Plasma characterization of Tetra III chrome etch system." In SPIE Photomask Technology, edited by Larry S. Zurbrick and M. Warren Montgomery. SPIE, 2009. http://dx.doi.org/10.1117/12.833490.

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Saveliev, Dmitry Evgenievich, Darkhan K. Makatov, and Vasily Sergeevich Portnov. "Solid inclusions in the chromitites of Geofizicheskoe-VII deposit (Kempirsay massif, Kazakhstan)." In Проблемы минералогии, петрографии и металлогении. Научные чтения памяти П. Н. Чирвинского. ПЕРМСКИЙ ГОСУДАРСТВЕННЫЙ НАЦИОНАЛЬНЫЙ ИССЛЕДОВАТЕЛЬСКИЙ УНИВЕРСИТЕТ, 2022. http://dx.doi.org/10.17072/chirvinsky.2022.219.

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Solid inclusions in chromite grains of Geofizicheskoe VII deposit located in Dzharlybutak area hosting the largest ophiolitic chromitite resources in the world are described. We show that mineralogical composition of inclusions (olivine, serpentine, chlorite, pargasite, PGM, base metal sulfides) is more various in comparison to that of host ultramafic rocks (olivine, enstatite, serpentine). PGM are predominantly disulfides of refractory PGE, rarely – native Ru-Os-Ir solid solutions. PGM inclusions always locate in chromite grains and they often form intergrowth with chlorite. We infer that the inclusions in chromite grains would been formed by solid state processes (deformation-induced breakdown of pyroxenes, impurity segregation in spinel, etc.) during high-T plastic flow and recrystallization at upper mantle conditions.
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Guan, Yabo, Harlan Bruner, Narayan Yoganandan, Frank A. Pintar, and Dennis J. Maiman. "Block-Fixation Finite Element Lumbar Spine Model to Examine Load-Sharing, Bone-Screw Interaction, and Stress in Carbon Fiber Reinforced PEEK Construct." In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206654.

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Carbon-fiber-reinforced (CFR) polyetheretherketone (PEEK) combines the high strength of metals with the extensive biocompatibility and imaging compatibility of polymers. CFR PEEK composite is similar to the stiffness of cortical bone (approximately 15–20 GPa) and shows comparable performance to metallic materials such as titanium alloy, cobalt chrome alloy, and stainless steel in terms of strength. CFR-PEEK becomes an attractive alternative to the metallic materials traditionally used in spinal implants (e.g. pedicle screw rod fixation). Finite element (FE) models have been developed to study the biomechanical behaviors of spinal structures with pedicle screw rod fixation ([1–5]). However, it is limited to implement these models to study the bone screw interaction, and local bone strain at the bone screw interface due to the intrinsic low mesh density of the intact model. The aim of this study is to develop a refined block fixation FE model to investigate the load sharing, bone screw interaction, and strain/stress in CFR PEEK construct.
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Kwon, Sung-Won, Dong-Chan Kim, Dong-Seok Nam, Sang-Gyun Woo, and Han-Ku Cho. "Plasma monitoring of chrome dry etching for mask making." In SPIE Photomask Technology, edited by M. Warren Montgomery and Wilhelm Maurer. SPIE, 2010. http://dx.doi.org/10.1117/12.866828.

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Dufaye, Félix, Astrid Sippel, Mark Wylie, Edgardo García-Berríos, Charles Crawford, Carl Hess, Luca Sartelli, et al. "Inline detection of Chrome degradation on binary 193nm photomasks." In SPIE Photomask Technology, edited by Thomas B. Faure and Paul W. Ackmann. SPIE, 2013. http://dx.doi.org/10.1117/12.2029470.

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Sim, Jeffrey, Tak-Seng Lai, Riza Bual, See Boon K. Tan, Aravinda Krishnappa, Derrick Wu, Xiaosong Zhang, Wooyong Kim, Chit-Wei Lee, and Peter Peng. "Predictive chrome-film haze mask management for mass production." In SPIE Advanced Lithography, edited by Christopher J. Raymond. SPIE, 2010. http://dx.doi.org/10.1117/12.855945.

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Danilenko, I. A., S. L. Votyakov, D. A. Zamyatin, and I. S. Chashchukhin. "Selection and verification of intralaboratory reference samples to assess Fe oxidation state in chrome spinels using electron probe microanalysis." In THE 2ND INTERNATIONAL CONFERENCE ON PHYSICAL INSTRUMENTATION AND ADVANCED MATERIALS 2019. AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0036596.

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Ning, Guoxiang, Selvi Gopalakrishnan, Thomas Thamm, Nikolay Oleynik, Paul Ackmann, Remi Riviere, Stephanie Maelzer, and Yee Mei Foong. "Alternative material to mitigate chrome degradation on high volume ArF layers." In SPIE Photomask Technology, edited by Thomas B. Faure and Paul W. Ackmann. SPIE, 2013. http://dx.doi.org/10.1117/12.2025466.

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Reports on the topic "Chrome Spinel"

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Cogulu, E. H. Factors controlling postcumulus compositional changes of chrome-spinels in the Crystal Lake Intrusion, Thunder Bay, Ontario. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1993. http://dx.doi.org/10.4095/192440.

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