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Thèses sur le sujet « Chromista »

Auteur : Grafiati
Publié le 2 juin 2025
Mis à jour le 31 juillet 2025

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1

Ginuino, Ione Soares Ferreira. "Blastocystis hominis Brumpt 1912 (Chromista: Blastocystea) em c?es e gatos de domic?lios localizados na regi?o Metropolitana do Rio de Janeiro." Universidade Federal Rural do Rio de Janeiro, 2006. https://tede.ufrrj.br/jspui/handle/tede/876.

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Made available in DSpace on 2016-04-28T20:17:29Z (GMT). No. of bitstreams: 1 2006-Ione Soares Ferreira Ginuino.pdf: 594140 bytes, checksum: 1524f0a5e00c7f5bb986fa9cebab4c20 (MD5) Previous issue date: 2006-03-24<br>With the objective to determine frequency, age and sex influences, and risk factor associated to Blastocystis hominis in feces of housed dogs and cats from the Metropolitan Region of Rio de Janeiro, Brazil, 234 fecal samples were collected by convenience from 175 dogs and 59 cats. To the diagnostic of B. hominis in fecal samples, direct examination was used, but ferric-hematoxilin
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2

Johnson, Caroline. "Podiform chromite at Voskhod, Kazakhstan." Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/40714/.

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The Voskhod podiform chromitite is one of more than 30 chromitite deposits that collectively form the Main Ore Field (MOF) within the Kempirsai Massif, in Kazakhstan. The MOF is the largest podiform chromitite ore-field in the world. The Voskhod deposit, encased in a serpentinised dunite halo, is situated within harzburgite units that comprise the mantle sequence of the Kempirsai ophiolite. This study arose from a unique opportunity to work on drill core samples through an un-mined podiform chromite deposit and investigate its internal structure, composition and genesis. The 18Mt ore-body has
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3

Kleynhans, Ernst Lodewyk Johannes. "Unique challenges of clay binders in a pelletised chromite pre–reduction process : a case study / Kleynhans E.L.J." Thesis, North-West University, 2011. http://hdl.handle.net/10394/7370.

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As a result of increasing cost, efficiency and environmental pressures ferrochrome producers strive towards lower overall energy consumption. Increases in local electricity prices have placed particular pressure on South African ferrochrome producers. Pelletised chromite pre–reduction is likely the currently applied ferrochrome production process option with the lowest specific electricity consumption. In this process fine chromite, together with a carbonaceous reductant and a clay binder is milled, pelletised and pre–reduced. In this dissertation it is demonstrated that the functioning of the
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Broughton, Richard. "Omega 3 fatty acids : identification of novel fungal and chromistal sources." Thesis, Royal Holloway, University of London, 2012. http://repository.royalholloway.ac.uk/items/38797691-c5ac-ef52-3a6c-12c3097e2765/6/.

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There is a wealth of scientific evidence associating the dietary intake of omega 3 long-chain polyunsaturated fatty acids with beneficial health properties. In this study, alternative natural sources of these polyunsaturated fatty acids are sought from novel low temperature isolated fungi. Over 100 low temperature isolated fungi were screened for very long chain polyunsaturated fatty acids (VLCPUF As), such as C20:5 n3 and C22:6 n3. Of those screened, only ten fungi were capable of VLCPUFA production, with Mortierella the predominant VLCPUF A producing species. Four Oomycete species were also
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5

Zargar, Hamidreza. "Sintering studies of magnesia-chromite refractory composites." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46175.

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The magnesia-chromite refractory composites are the best candidates for the lining of non-ferrous metal smelting and refining furnaces, due to their high melting temperature, chemical inertness, and excellent thermal shock resistance. However, their high sintering temperatures (>1700°C) increase the processing complexity and costs. In this investigation, the primary goal was to study the sintering of these composites, with the long-term engineering goal to reduce their sintering temperature to <1500°C in air. The materials were synthesized via chemical methods using nitrates to assure chemica
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6

Smith, Roger. "A Mossbauer study of chromite-magnesia refractories." Thesis, Sheffield Hallam University, 1994. http://shura.shu.ac.uk/20372/.

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A range of natural chrome ores, containing iron in two valence states, have been investigated using the technique of Mossbauer spectroscopy. The instrumentation required to cry out the technique was studied and an additional item of equipment was designed and constructed to extend the temperature range over which the effect could be observed. All the chrome ores yielded a complex spectra which could be attributed to a combination of octahedrally and tetrahedrally co-ordinated Fe2+ and Fe3+ quadrupole doublets. A model for fitting the spectra was devised assuming the presence of octahedrally co
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7

Pedrotti, M. "CHROMITE: FROM THE MINERAL TO THE COMMODITY." Doctoral thesis, Università degli Studi di Milano, 2013. http://hdl.handle.net/2434/216116.

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Chromite belongs to the spinel group with the general chemical formula XY2O4, where X and Y represent divalent and trivalent metal ions, respectively. Four types of chromite ore deposits occur as either lode or secondary deposits. Lode chromite ore deposits comprise stratiform and podiform deposits, whereas secondary chromite ore deposits comprise laterite and placer deposits. Chromite is an important industrial mineral used in the refractory industry. Moreover it is the only industrial source of chromium for chemical and metallurgical industries and to be marketed as a valuable commodity it
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8

Bourdin, Marie. "Poudres et films à base d'oxyde de tungstène WO3 pour applications photoniques : photochromisme et électrochromisme." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0013.

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Dans cette étude, la synthèse en milieu polyol est utilisée afin d’obtenir des oxydes de tungstène nanostructurés et présentant une légère sous-stœchiométrie en oxygène (WO3 x). Les particules obtenues sont de couleur bleue, et possèdent des propriétés optiques intéressantes du fait de la présence d’ions W5+. Les traitements thermiques de ces particules à différentes températures ou sous différentes atmosphères permettent de contrôler la sous-stœchiométrie en oxygène et donc leurs propriétés optiques (et leur couleur) ; leur teinte allant du jaune pâle pour les composés recuits sous une atmosp
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9

Yalcin, Sezgin. "Modeling Chromium Leaching From Chromite Ore Processing Waste." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/4/1053412/index.pdf.

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Chromium has been widely used in many industrial applications. As a result of chromite ore processing, large amounts of chromite ore processing waste (COPW) material that can be classified as hazardous have been produced and released into the environment. Therefore, knowledge of migration behavior and leaching rates of chromium through waste materials and soils are of primary concern for environmentally sound management of land-disposal hazardous wastes. Hask&ouml<br>k (1998) experimentally studied leaching rates of total Cr and Cr(VI) using laboratory columns packed with chromium COPW materia
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10

Musa, Caston Tamburayi. "Eluvial chromite resources of the Great Dyke of Zimbabwe." Thesis, Rhodes University, 2007. http://hdl.handle.net/10962/d1007731.

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Apart from the concentrations of chromite in layers within the Great Dyke and other ultramafic complexes, chromite also occurs as interstitial grains throughout the olivine-bearing rock-types. These olivine-bearing rocks include no rites, gabbros, dunites and pyroxenites. Chromite concentration in these rocks varies from 0.48 to 3.09 per cent of the rock, usually in the form of chromite (Ahrens, 1965; Worst, 1960). A small fraction of this chromite settled to form chromitite layers whilst the remainder is retained within the rock mass as finely disseminated chromite and chromite interstitial t
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11

Barsova, Zoia. "Właściwości fizykochemiczne spinelu ZnCr₂Se₄ domieszkowanego wybranymi pierwiastkami d- i f-elektronowymi." Doctoral thesis, Katowice : Uniwersytet Śląski, 2020. http://hdl.handle.net/20.500.12128/16785.

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As part of this work, the synthesis of doped poly- and monocrystalline compounds based on ZnCr₂Se₄ was planned and carried out, and then their physicochemical characteristic was determined. The inspiration for the research consisted in its unusual physicochemical properties. This compound has a spinel structure and is a p-type semiconductor with a spiral magnetic structure. The d- and f-electron elements manganese, holmium and neodymium were chosen as admixtures, guided by different values of effective magnetic moment compared to chromium ions on III oxidation state. The synthesis of poly- an
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12

Boust, Clotilde. "Contribution à l'amélioration des images numériques par un algorithme fondé sur la démarche de l'expert chromiste." Paris 6, 2004. http://www.theses.fr/2004PA066025.

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13

Othman, Norinsan Kamil Materials Science &amp Engineering Faculty of Science UNSW. "Steam effects on cyclic oxidation of chromia forming alloys." Awarded by:University of New South Wales. Materials Science & Engineering, 2009. http://handle.unsw.edu.au/1959.4/44528.

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High temperature oxidation of Fe-Cr alloys with Cr levels of 9-30 wt% has been investigated by using isothermal and cyclic experiments at 600, 700 and 950??C. The mixed gases Ar-20%02, Ar-20%02H20, Ar-5%02-20%H20, Ar-10%H2-5%H20 and Ar-10% H2-20%H20 at total pressure of I atm were used. The effect of lanthanum alloying on Fe-Cr alloy oxidation was also studied. In general, increasing alloy chromium levels reduced the oxidation rate. In isothermal oxidation at 700??C, a protective chromia layer was formed in dry oxygen for Fe9Cr. Alloys with Cr???17% formed protective chromia layers in all gas
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14

Ma, Qiang. "Haloethane Reactions over the Chromia Cr₂O₃ (1012) Surface." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/34754.

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Ethyl iodide and ethyl chloride have been used as reactants to produce ethyl fragments on the stoichiometric α-Cr₂O₃ (1012) surface by means of thermal dissociation. Ethyl iodide is dissociated giving iodine adatoms and ethyl fragments bound to surface Cr cation sites, while ethyl chloride is dissociated giving chlorine adatoms and ethyl fragments. No oxygenated products are observed in thermal desorption, suggesting the 3-coordinate lattice oxygen on the stoichiometric α-Cr₂O₃ (1012) surface is very stable, and no nucleophilic attack occurs at the carbon atoms on surface ethyl fragments. F
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15

Eadie, Edward Norman. "Pattern of international trade in chromite and ferrochromium : an historical perspective /." Title page, table of contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phe11.pdf.

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16

Azri, Hilal al. "Typologie des gisements de chromite dans la partie sud de l'ophiolite du Nord Oman /." Orléans : Ed. BRGM, 1987. http://catalogue.bnf.fr/ark:/12148/cb34928093n.

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17

Ustaoglu, Emre. "Optimization Of Conditions In Sulfuric Acid Leaching Of Turkish Chromite Concentrates." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/2/12607344/index.pdf.

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In this thesis work, a high grade chromite concentrate obtained from PinarbaSi, Kayseri region of Turkey was reacted with sulfuric acid solution to determine the optimum conditions of leaching of chromite ores. Conventional methods for producing chromium are still valid in industry. The main process in production includes soda melting and taking it into solution in the form of chemical compounds such as sodium dichromate. Three and six valence states of chromium have importance in production. Trivalent chromium, chrome ore or chromite have no harmful effects. However, compounds of hexavalent c
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18

Kanitkar, Swarom R. "Modeling and Analysis of Production of Propylene Glycol over Copper Chromite." Thesis, University of Louisiana at Lafayette, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1585860.

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<p> Production of 1,2-propanediol through hydrogenolysis of glycerol over Copper-Chromite is a promising reaction pathway that has large potential markets. However, production is complicated by low catalyst stability and significant difficulty in preventing or removing unwanted reaction byproducts. These unwanted byproducts impart yellow color and foul odor, making the product sell at a much cheaper cost. In collaboration with a commercial partner, the authors investigated an economical way of liquid-liquid extraction for removing these unwanted byproducts. The authors also tried to model the
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19

Deakin, David. "The leaching of toxic metals from chromite ore processing residue (COPR)." Thesis, University of Leeds, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270896.

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20

Hu, Xianfeng. "Studies on Carbothermic Reduction of Chromite in the Presence of FeOx." Doctoral thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-60100.

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Direct chromium alloying by chromite ore is a promising technology for producing Crcontainingsteels, as the ferrochrome production process and the chromium alloying processare integrated into a single step, which has the potential of saving energy and raw materials.In this work Thermogravimetric Analysis experiments and induction furnace experiments (upto 80-kg scale) have been carried out to investigate the carbothermic reduction process ofchromite in the presence of FeOx (iron, mill scale or magnetite). The aims are to investigatethe effect of FeOx on the carbothermic reduction of chromite a
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21

Hop, Marina. "Dehydrogenation of N-Propanol to Propionaldehyde over a copper chromite catalyst." Master's thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/18796.

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Methyl methacrylate (MMA) is widely used for a range of polymer products. MMA can be produced from propionaldehyde via the BASF process. n-Propanol is readily available 'in South Africa as a byproduct of Fischer-Tropsch synthesis. This prompted an investigation into the production of propionaldehyde by the dehydrogenation of n-propanol. There is presently no established technology for the dehydrogenation of n-propanol to propionaldehyde and there has been very little work carried out on the effect of process variables on propionaldehyde yield. The emphasis of the current work was optimising pr
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22

Taneka, S. "Carbothermal reduction of friable chromite in a small-scale transferred-arc furnace." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37873.

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23

Moat, Thomas. "Structural and petrochemical studies of chromite in the Vourinos ophiolite, NW Greece." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292414.

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Anunike, Chidinma. "Deployment of calcium polysulphide for the remediation of chromite ore processing residue." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=227912.

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Chromium contamination of groundwater and soils continues to pose a major environmental concern. Soils may have become contaminated with chromium through former industrial activities geochemical enrichment. The nature of the industrial activity will determine the form and concentration of the chromium as well as the presence of co-contaminants and the pH and redox of the soil. Chemical reductants have been widely used for the transformation of hexavalent chromium in the environment. Over recent decades attention focused on the chemical reductant calcium polysulphide which has performed effecti
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25

Elvin, Nowak Hannes. "Framgång i amfibieoperationer : En teoriprövande studie om framgång i Operation Chromite, 1950." Thesis, Försvarshögskolan, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-8599.

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This paper examines how Speller’s theory of success in amphibious operations can be applied on a successful amphibious operation. The research has been encouraged by the fact that previous research concerning success in amphibious operations appears to be lacking. No previous studies of the theory have been found, which further strengthen the necessity for this study. The theory is examined by a single-case study of the recognised amphibious assault on Inchon during the Korean War. The theory is able to explain the success, otherwise the credence to the theory would be refuted. The result of t
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Huang, An-Rong. "Synthèse par procédé sol-gel du chromite de lanthane pour éléments chauffants." Montpellier 2, 1995. http://www.theses.fr/1995MON20039.

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Des poudres de chromite de lanthane ont ete preparees par procede sol-gel en milieu aqueux a partir de deux precurseurs: nitrates ou acetates. Les sols colloidaux ont ete obtenus par precipitation et peptisation en ajoutant de l'ammoniaque. Les zones de ph de precipitation et de peptisation ont ete determinees par des dosages acidobasiques. Apres gelification a l'air, la decomposition des gels a ete etudiee par analyse thermique (atg - atd) et par spectroscopie ir ; la cristallisation du chromite de lanthane, obtenu par traitement thermique des gels a ete determinee par diffractometrie des rx
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Morelli, Marcio Raymundo. "Liquid phase sintering of perovskite." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297279.

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Engweiler, Jörg C. "Titania based vanadia, chromia and tungsten oxide catalysts prepared by grafting /." [S.l.] : [s.n.], 1995. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10960.

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Hu, Xianfeng. "Fundamental Studies on Direct Chromium Alloying by Chromite Ore with Designed Alloying Precursor." Licentiate thesis, Luleå tekniska universitet, Mineralteknik och metallurgi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18117.

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Chromium is an important alloying element for stainless steels and other Cr-bearing steels. During the steelmaking process chromium is added to the steels mainly in the form of ferrochrome, which is largely produced by the energy-intensive smelting reduction process of chromite ore in the submerged arc furnace. To reduce the overall energy consumption during the ferrochrome production process and the chromium alloying process, direct chromiumalloying by chromite ore has been proposed. The application of this process will integrate the processes for ferrochrome production and chromium alloying,
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Escudero, Castejon Lidia. "Novel reductive alkali roasting for Cr6+-free extraction of Cr2O3 from chromite ores." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/22530/.

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Chromite ore is the raw material used in the manufacturing of ferrochromium, which is an important metallurgical product employed in the stainless-steel industry. Chromium-based chemicals have also a wide range of applications, including pigments industry, leather tanning processes and surface treatments. The production of chromium chemicals is based on the alkali roasting of chromite ore in oxidising atmosphere in order to extract chromium as water soluble alkali chromate (Na2CrO4, K2CrO4). The main drawback of this process is the inevitable generation of a hazardous processing waste containi
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Azri, Hilal al. "Typologie des gisements de chromite dans la partie de l'ophiolite du Nord Oman." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb375956227.

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Malézieux, Jean-Marie. "Contribution à l'étude de spinelles de synthèse et de chromites naturelles par microsonde raman laser." Lille 1, 1985. http://www.theses.fr/1985LIL10009.

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Analyse des spectres Raman, obtenus par microsonde M. O. L. E, d'une série de spinelles de synthèse : MgAl(2-x)Cr(x)O(4), FeAl(2-x)Cr(x)O(4), Mg(1-x)Al(2)O(4), Mg(1-x)Fe(x)Al (2)O(4), Mg(1-x)Fe(x)Cr(2)O(4), Mg(1-x/2)Fe(x/2)Al(2-x)Cr(x)O(4) et de chromites naturelles (Mg, Fe(2+)) (Cr, Al, Fe(3+))(2)O(4) associées à des roches ultrabasiques ; mise en évidence de deux types de comportement vibrationnel (à un mode et à deux modes) dans le cas des spinelles et d'un seul (un mode) dans le cas des chromites ; analyse des déplacements de fréquences et des variations d'intensités des bandes en fonction
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Benoot, Nicolas. "Self-assembly of hybrid microgels for interferential and responsive photonic applications." Electronic Thesis or Diss., Pau, 2020. http://www.theses.fr/2020PAUU3047.

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Dans le milieu des produits cosmétiques et de soins pour la peau, il existe un réel besoin d’innovation pour trouver de nouveaux matériaux sans impact sur le consommateur et l’environnement. Dans une démarche bio-inspirée, les couleurs dites « physiques » offrent une nouvelle voie de création de couleurs sans pigments inorganiques. En effet, aujourd’hui les pigments minéraux sont la principale source de coloration pour les applications cosmétiques et leur remplacement représente un enjeu critique pour limiter une éventuelle exposition à de potentielles nanoparticules.Sensible à cet enjeu, LVMH
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Sagatowska, Iga. "Chromite in serpentine mud volcanoes of the Mariana forearc: Implications for abiotic organic reactions." Thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-40706.

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The Mariana convergent plate margin is a non- accretionary subduction system in the western Pacific Ocean. Subduction of the Pacific plate causes dissolution of carbonate minerals releasing inorganic carbon, and causes dehydration of hydrous minerals in the subducted slab, generating hydrous fluids. The hydrous fluids infiltrate the overriding plate and induce serpentinization of mantle peridotite. Serpentinized material is transported by the rising fluids, which are channeled along fractures and faults in the forearc region, consequently erupting at the seafloor forming serpentine seamounts.
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Sattari, Parisa. "Experimental constraints on the chromite-melt partitioning behaviour of rhenium and platinum-group elements." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0019/MQ53465.pdf.

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Neizel, Bryson Wade. "Alteration of chrome-to-iron ratio in chromite ore by chlorination / Bryson Wade Neizel." Thesis, North-West University, 2010. http://hdl.handle.net/10394/4313.

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The industrial importance of the chromium industry to South Africa is emphasised by the fact that it is considered the largest chromite (chromium ore) and ferrochrome (chrome-iron alloy) producing country in the world. Although South Africa holds three quarters of the world's chromite ore reserves, the chrome-to-iron (Cr-to-Fe) ratio of the local chromite ores is relatively low (1.47 to 1.55), compared to other deposits in the world (2.6 to 3.5). Additionally, iron is more readily reduced than chromium. The combination of these two factors implies that ferrochrome produced from South African c
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Ould, Souelim Moktar. "Les roches mafiques et ultramafiques de Guidimaka (Mauritanie) et les gisements de chromite associés." Nice, 1990. http://www.theses.fr/1990NICE4438.

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Les Mauritanides renferment dans leur zone axiale des roches mafiques et ultramafiques témoins d'une paléo-ophiolite. Au Guidimaka, les tectonites mantellaires sont représentées par des harzburgites et des dunites totalement serpentinisées. Les héteradcumulats wehrlitiques et webstéritiques caractérisent la zone de transition. La séquence cumulative mafique est composée de mésocumulats gabbroïques et gabbronoritiques. Les gabbros à amphibole et les ferrogabbros sont les termes les plus différenciés. Ces laves et dolérites ont des compositions chimiques de tholéitiques à olivine enrichies, et d
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38

Kanari, Ndue. "Extraction des métaux de valeur des concentrés de chalcopyrite et de chromite par chloruration." Vandoeuvre-les-Nancy, INPL, 1995. http://docnum.univ-lorraine.fr/public/INPL_T_1995_KANARI_N.pdf.

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La métallurgie extractive de métaux non ferreux tels que le cuivre, etc. Génère des effluents gazeux et liquides ainsi que des déchets solides. Malgré les efforts faits par ce secteur d'activité, ces rejets, même partiels, posent des problèmes pour l'environnement. Ce travail est focalisée sur la possibilité de la chloruration sélective des concentrés de chalcopyrite et de chromite dans le but de récupérer ou de concentrer les métaux de valeur. Deux concentrés de chalcopyrite et un concentré de chromite ont été utilisés. La chloruration de ces solides est réalisée en montage horizontal et en A
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Šuráň, Jiří. "Tepelné vlastnosti forem v závislosti na použitém ostřivu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230177.

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The project elaborated in frame of engineering studies is submitting the study of thermal properties of holding mixtures using different types of sand. Were tested a total of 5 sands: zirkon, ŠH22, chromite, olivine and dunite. Molding compounds were tested for thermal capacity, thermal conductivity and heat accumulation. The highest heat capacity was achieved in dunite sand. The largest heat accumulation had mixture with chromite sand and the best thermal conductivity was found in a mixture with olivine sand.
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Ivanic, Tim. "The chromite-garnet peridotite assemblages and their role in the evolution of the mantle lithosphere." Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/15085.

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Newlands and Bobbejaan kimberlites, South Africa, contain suites of highly chromian, garnet-rich peridotites amongst their xenolith population and an investigation of these xenoliths has been targeted because there is an overlap of mineral compositions with the garnet-chromite-olivine paragenesis found as inclusions in diamonds. A high proportion of garnets and chromites in these rocks plot in the diamond facies fields on Cr<sub>2</sub>O<sub>3</sub>-CaO and Cr<sub>2</sub>O<sub>3</sub>-MgO wt. % plots respectively. However, it has also been found that many Cr-rich assemblages are clinopyroxene-
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De, Beer Francis. "The characterisation of a two stage flotation circuit treating a complex platinum and chromite ore." Master's thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/16119.

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Bibliography: pages [144]-152.<br>The methodology was developed to characterise the complex MF2 circuit at Impala Platinum Ltd. The circuit was divided into individual units and each unit was evaluated over a period of time. The performance of each unit in terms of platinum, palladium, rhodium and chromite recoveries was determined by sampling around the unit. The changes in ore floatability characteristics were monitored by carrying out batch flotation tests on samples taken from the feed to each unit. The mixing in the units was characterised by performing residence time distribution studies
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Zwolensky, Todd S. "Logistics over the shore : a review of Operation Chromite, Operation Bluebat and its relevance today /." Fort Leavenworth, Kan. : [U.S. Army Command and General Staff College], 2007. http://handle.dtic.mil/100.2/ADA475691.

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Brooks, John Daniel. "Model Chromia Surface Chemistry: C2 Alkyl Fragment Reactions and Probe Molecule Interactions." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/29161.

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The thermally induced reaction of chlorinated ethanes on the nearly-stoichiometric α-Cr₂O₃ (102) surface results in the formation of gas phase hydrocarbons including ethylene, ethane, acetylene, 2-butene, 2-butyne and dihydrogen, and deposition of surface chlorine adatoms. No surface carbon or combustion products are observed in any reactions indicating that no thermally induced C-C bond cleavage occurs and surface lattice oxygen is not incorporated into surface intermediates. A combination of photoemission and Auger electron spectroscopies indicates the surface reactions of the chlorinated et
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Michalik, Marek. "Effect of water vapour on growth and adherence of chromia scales on pure chromium." [S.l.] : [s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=985669020.

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Michalik, Marek Hänsel Michael Quadakkers Willem Joseph. "Effect of water vapour on growth and adherence of chromia scales on pure chromium /." Jülich : Forschungszentrum, Zentralbibliothek, 2007. http://www.loc.gov/catdir/toc/fy0803/2007464877.html.

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Alexiou, Amanda Elton. "The effects of chromia coatings on the oxidation characteristics on Ni and Ni-20Cr." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/15046.

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Brough, Christopher Paul. "An investigation into the link between anomalous PGE concentrations and chromite composition in chromitites within ophiolites." Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/54211/.

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For all three ophiolites, variations in chromitite major and trace element geochemistry occur on several different scales. At the smallest level, single thin sections of chromite may sometimes display large variations in composition. At the next level, intrapod chemical variation can be extensive, though predominantly displaying an inverse correlation between Cr# and Mg#. Finally, interpod variation, and its relationship to stratigraphic height, changes a great deal between ophiolites, sometimes providing an apparently continuous change with height (e.g. Al 'Ays) and in other places (e.g. Shet
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McLean, Michael M. "Phenyl Functionalized Sol-gel Silica Sorbent for Capillary Microextraction and Chromia-Based Sol-gel Ucon Stationary Phase for Capillary Gas Chromatography." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5374.

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The first chapter of this thesis presents an introduction to sol-gel methodology whose usefulness as a synthetic route will be demonstrated with two applications in chromatography. The first application involves the fabrication of a capillary micro-extraction (CME) device by coating a phenyl functionalized extracting phase on the inner surface of a fused silica capillary for analyte pre-concentration. The device was coupled on-line to a RP-HPLC system and practicality was demonstrated using allergens as target analytes. The allergens chosen as model analytes are typically found in fragrance pr
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Opoubou-Lando, Serge-Driver. "Mineralogical characterisation of chromite in the UG2 Reef from Waterval Mine, Western bushveld : implications for minerals processing." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4380.

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Thesis (MSc (Earth Sciences))--University of Stellenbosch, 2010.<br>ENGLISH ABSTRACT: The Bushveld Complex of South Africa contains three of the most important platinum deposits in the world namely the Merensky Reef, the Upper Group Two (UG2) chromitite reef and the Platreef. These three ore bodies are principally beneficiated by froth flotation. During the beneficiation of chromite hosted PGE’s by froth flotation, chromite represents the principal gangue mineral. This is particularly true for the UG2 main seam. An excess of more than 3% in mass of chromite in the PGM concentrate is known
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Al-Aabed, Solaiman. "Petrogeneis of chromite and associated minerals in the upper mantle peridotite of the northern Semail ophiolite (UAE) /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488196781733841.

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