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Dissertations / Theses on the topic 'Chromace'

Author: Grafiati

Published: 29 March 2025

Last updated: 31 July 2025

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1

Del, Pianta Dimitri. "Détermination des paramètres physcio chimiques régissant l’électrodéposition d’une couche de chrome métallique à partir d’une solution de chrome trivalent." Thesis, Pau, 2017. http://www.theses.fr/2017PAUU3035/document.

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De par leurs propriétés mécaniques et anti-corrosion élevées, les revêtements métalliques de chrome sont utilisés dans de nombreux domaines tels que l’aéronautique, l’automobile, le ferroviaire, la défense,… Aujourd’hui le chromage dur industriel, réalisé à partir de chrome hexavalent, est fortement menacé par la directive européenne REACH qui prévoit l’interdiction d’utilisation de sels de chrome VI (classé CMR) à l’horizon 2017. Dans ce contexte le projet HCTC (Hard Chromium by Trivalent Chromium) regroupe 16 partenaires industriels et 2 partenaires académiques sous la coordination de l’Inst

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2

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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3

Parsa, Yohan. "Oxydation thermique du chrome pur en atmosphère contrôlée : propriétés semiconductrices et structurales de la chromine." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAI081/document.

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La durabilité chimique des alliages métalliques résulte notamment de la nature des défauts ponctuels assurant le transport au travers du film d’oxydation formé en surface. L'élaboration de couches d'oxyde modèles par oxydation thermique en pression contrôlée et ALD (Atomic Layer Deposition) et l'étude de leurs propriétés semi conductrices (conditionnées par la nature des défauts ponctuels) devrait permettre une meilleure compréhension des mécanismes de formation de ces couches d'oxyde<br>The chemical durability of the metal alloy results in particular from the nature of point defects providing

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4

Rolet, Jason. "Influence de la forme de l'onde de polarisation sur la microstructure et les propriétés de revêtements électrolytiques élaborés à base de chrome trivalent." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCD010.

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Ce travail de thèse s’inscrit dans un projet de grande envergure piloté par l’IRT M2P, intitulé « Hard Chrome by Trivalent Chromium » qui regroupe 15 partenaires industriels et 2 partenaires académiques. L’objectif principal est de substituer les composés du chrome hexavalent par des électrolytes à base de chrome trivalent dans les procédés de chromage « dur », en réponse à l’application du règlement européen REACH en septembre 2017, même si des demandes d’autorisations temporaires sont en cours. Dans le cadre de cette thèse, des études électrochimiques ont été réalisées sur des bains commerci

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5

Presley, Christopher Charles. "Isolation, Structure Elucidation, and Total Synthesis of Biologically Active Natural Products from Plants." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/79978.

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As a part of the continuing search for bioactive compounds with the Madagascar International Cooperative Biodiversity Group (ICBG), and in collaboration with the Natural Products Discovery Institute of the Institute for Hepatitis and Virus Research (IHVR), thirteen plant extracts were investigated for antiplasmodial activity, thirteen plant extracts were investigated for antiproliferative activity, and one extract was investigated for inhibitors of the shikimate pathway in Plasmodium falciparum. Bioassay-guided fractionation of the extracts led to the identification of nineteen compounds with

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6

Tissot, Louis-Jean. "L'Ouvrage incomplet sur Matthieu (Opus imperfectum in Matthaeum) et les commentaires en latin sur l'évangile de Matthieu de l'Antiquité. Comparaison exégétique et stylistique ciblée sur la partie A (Mt. 1-8)." Electronic Thesis or Diss., Sorbonne université, 2024. http://www.theses.fr/2024SORUL158.

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S'inscrivant dans le projet d'édition critique de l'Ouvrage incomplet sur Matthieu (Opus imperfectum in Matthaeum, OIM), la présente thèse analyse les liens entre ce commentaire anonyme sur l'évangile de Matthieu, provenant d'un milieu subordinationiste riminien (i.e. « homéen »), et d'autres ouvrages exégétiques latins sur le même évangile. Après avoir rappelé, dans un état de la recherche, les principales caractéristiques du corpus pris en compte, nous avons procédé à une comparaison exégétique suivie portant sur la section Mt 1-8, correspondant à la première partie de l'OIM, avec les commen

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7

Li, Longfei. "Study of Corrosion and Corrosion Inhibition of Chromate and Chromate-Free Primers." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1344896405.

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8

Adjei, Mensah Evelyne. "Dissémination environnementale du chrome en contexte minier : études physique, chimique et isotopique." Electronic Thesis or Diss., Université Paris Cité, 2022. http://www.theses.fr/2022UNIP7060.

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L'étude du cycle des métaux dans l'environnement et de l'impact de l'activité anthropique constitue un enjeu environnemental et sanitaire important. Les sites ultramafiques sont caractérisés par leur faible teneur en nutriments (N, P et K), leur minéralogie dominée par les oxydes de Fe et leur enrichissement naturel en métaux tels que Cr, Fe et Ni. Ces systèmes ultramafiques sont des sites de choix pour les compagnies minières. Les activités minières génèrent plusieurs tonnes de déchets miniers tels que les résidus miniers, les minerais peu concentrés et les terrils. Ces déchets miniers peuven

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9

Abdelouhab, Sandra. "Détermination de grandeurs physico-chimiques dans les verres fondus - Relation avec le comportement en corrosion du chrome et d'alliages chromine-formeurs." Nancy 1, 2005. http://www.theses.fr/2005NAN10155.

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Ce travail de thèse a eu pour buts : - d'édifier une échelle de basicité dans les milieux verres fondus. Une cellule électrochimique permettant la détermination in situ des activités en Na2O et appelée méthode des piles de concentrations a été développée. Cette méthode a permis de mesurer la basicité de verres de compositions simplifiées et industrielles pour les comparer entre eux et critiquer les modèles de basicité existants. - de déterminer la solubilité de Cr2O3 dans les fontes de verres et montrer que la teneur en chrome dissous dépend de la température d'expérience, de la basicité du ve

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10

Woodbridge, Nesta. "Mechanistic studies relevant to chromate toxicity." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267077.

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11

Oki, Makanjuola. "Conversion coatings on aluminium." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390302.

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12

Magalhães, Alvaro Augusto Oliveira. "Étude de couches de conversion chimiques sur les surfaces zinguées : mécanisme de la formation des couches de chromatation et évaluation de couches de conversion alternatives à base de molybdate." Paris 6, 2002. http://www.theses.fr/2002PA066236.

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13

Deschamps, Frédéric. "Etude epidemiologique des causes de deces dans une fabrique de pigments a base de chromates." Lille 2, 1993. http://www.theses.fr/1993LIL2P269.

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14

Akuamoah, Robert Kwado. "Studies in chromene chemistry." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358888.

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15

Mugada, Trilok Ranjan. "Superprimer chromate free coating system for DoD applications /." Cincinnati, Ohio : University of Cincinnati, 2006. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1145383075.

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16

Whittleston, Robert Andrew. "Bioremediation of chromate in alkaline sediment-water systems." Thesis, University of Leeds, 2011. http://etheses.whiterose.ac.uk/2024/.

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The poorly controlled disposal of chromium ore processing residue (COPR) is a globally widespread problem due to its potential to form chromium contaminated hyperalkaline (pH > 12) leachates. These highly oxidising leachates typically contain chromium in the Cr(VI) oxidation state as its chromate anion (CrO42-). This anion is highly mobile, toxic, carcinogenic, and exhibits a high degree of bioavailability. Under reducing conditions chromium exists in the non-toxic and poorly soluble Cr(III) oxidation state. Thus, the reduction of Cr(VI) to Cr(III) is often the goal of remediative strategies.

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17

Fletcher-Wood, Rowena. "Zeolites and other molecular sieves for chromate remediation." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5789/.

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Porous solids loaded with redox-active ions were examined for the selective uptake and simultaneous reduction of Cr(VI) from aqueous solution. XRF spectroscopy was used to determine the extent of chromium uptake by molecular sieves: 29.1 mg\(_C\)\(_r\)/g\(_s\)\(_i\)\(_e\)\(_v\)\(_e\) for Mn-loaded AIPO-5. Some systems were templated: TEM confirmed the introduction of mesopores. Mössbauer and EPR spectroscopies characterised oxidation states and site symmetries of metal ions. Fe(II)-loaded molecular sieves were found to be appreciably oxidised (~ 80 %). To increase the fraction of redox-active

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18

Yoon, Tae-Ho. "Phosphate stabilization by non-chromate post-rinse treatment." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/80009.

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Zinc phosphate conversion coating has been applied to improve the corrosion resistance and paint adhesion. However, zinc phosphate crystals dissolve in a highly alkaline environment, which reduces the corrosion resistance of base metal. To improve the phosphate stability in a highly alkaline environment, a post-rinse treatment has been applied to phosphate coating by rinsing with an aqueous solution which contains certain anions or cations. Chromatepost-rinse treatment is the most widely used method and has shown a great improvement in corrosion resistance. But, due to the environmental proble

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19

MUGADA, TRILOK RANJAN. "SUPERPRIMER: CHROMATE FREE COATING SYSTEM FOR DoD APPLICATIONS." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1145383075.

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20

Loyaux, Lawniczak Stéphanie. "Mécanismes d'immobilisation du chrome dans les sols : diagnostic de la pollution d'une friche industrielle et réactivité des ions chromates vis-à-vis du fer divalent." Nancy 1, 1999. http://docnum.univ-lorraine.fr/public/SCD_T_1999_0260_LOYAUX_LAWNICZAK.pdf.

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Ce travail porte sur les processus chimiques régissant le transport et l'immobilisation du chrome dans les sols. Les travaux présentés comportent deux volets : l'étude environnementale de la localisation du polluant sur un ancien site industriel et une étude en laboratoire visant à mettre en évidence les mécanismes réactionnels responsables de l'immobilisation du chrome dans les sols. L'étude de la pollution sur le site permet de montrer qu'il existe dans la nappe du sous-sol un front d'oxydoréduction permettant de stopper la migration du Cr (VI) issu du terril de résidus de minerais. La réact

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21

congom, nom. "PProva chrome." Doctoral thesis, TDX (Tesis Doctorals en Xarxa), 2020. http://hdl.handle.net/10803/671805.

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22

SCHMITT, DANIELLE. "Biologie du chrome : relations chrome et maladies cardio-vasculaires." Strasbourg 1, 1989. http://www.theses.fr/1989STR15042.

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23

Lunder, Otto Reidar. "Chromate-free Pre-treatment of Aluminium for Adhesive Bonding." Doctoral thesis, Norwegian University of Science and Technology, Department of Materials Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-285.

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<p>The increasing use of aluminium in automotive and transport applications is primarily driven by its high strength to weight ratio, enabling substantially improved fuel economy and reduced CO<sub>2</sub> emissions when substituted for heavier materials. However, the change of material presents new challenges with respect to design and methods of joining. Structural adhesive bonding offers several advantages compared with welding, but a major limitation is concern about the durability of joints in wet and corrosive environments. The pre-treatment of the aluminium surface prior to bonding is t

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24

Wharton, J. A. "Non-chromate conversion coating treatments for zinc-alloy electrodeposits." Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/7611.

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In recent years, the suspected carcinogenic and toxic effects of hexavalent chromium have caused great concern, resulting in the imposition of stringent environmental and workplace regulations in the metal finishing industry. This has lead to the search for suitable alternatives to the chromate formulations. In this investigation molybdate, cerium and permanganate-based solutions have been examined as to their suitability as possible replacements for chromate conversion coatings on zinc-alloy electrodeposits. Investigations have primarily concentrated on producing passive surfaces from molybda

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25

Fuller, Samuel James. "Sustainable engineering treatment for highly alkaline chromate contaminated groundwater." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/6339/.

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Chromite ore processing residue (COPR), a waste product from chromium extraction, is highly alkaline and is toxic due to the soluble Cr(VI) it contains. Unregulated dumping during the previous century led to many sites being contaminated with this waste. As Cr(VI) migrates in groundwater flows, reduction to less toxic and insoluble Cr(III) seems a prudent remediation strategy. Zero valent iron permeable reactive barriers (ZVIPRBs) and biobarriers are both capable of in-situ reduction reactions and were thus investigated for their suitability to treat COPR impacted sites. Reduction of Cr(VI) by

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26

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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27

Sabbagh, Liezel Veronica. "Chemical studies of chromone derivatives." Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1006899.

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This study has focussed on several aspects of chromone chemistry, viz., (i) the influence of remote substituents on the basicity of 2-(N,N-dimethylamino)chromones, (ii) MoritaBaylis-Hillman reactions of substituted chromone-3-carbaldehydes and (iii) an investigation into the application of chromone chemistry in the total synthesis of the marine natural product, Rietone A. Selected 2-(N,N-dimethylamino )chromones were prepared using two different methods; firstly, via cyclisation of salicylate-derived N,N-dimethyl-3;.(2-hydroxyphenyl)-3- oxopropanamide precursors and, secondly, via 2-hydroxyace

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28

Serres, Nicolas. "Réalisation et caractérisation de revêtements épais éco-respectueux réalisés par voie sèche destinés à remplacer des dépôts électrolytique." Strasbourg, 2010. https://publication-theses.unistra.fr/public/theses_doctorat/2010/SERRES_Nicolas_2010.pdf.

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Les matériaux utilisés industriellement sont de plus en plus sollicités dans des conditions extrêmes, exigeant résistance à l’usure et à la corrosion. A ces performances techniques s’ajoutent désormais des contraintes environnementales de plus en plus fortes nécessitant la recherche de traitements de surface alternatifs. L’objet de cette thèse est de remplacer le chromage dur électrolytique par des traitements par voie sèche, en garantissant performances techniques et environnementales par analyse du cycle de vie des dépôts. Afin de corriger certains défauts des dépôts obtenus par projection t

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29

Herzog, Teja. "Ultraschnelle Isomerisierungsreaktionen - Chromene, Hemithioindigo und Chromopeptide." Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-145766.

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30

Nchinda, Aloysius Tchangwe. "Chemical studies of selected chromone derivatives." Thesis, Rhodes University, 2002. http://hdl.handle.net/10962/d1007442.

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This investigation has been geared towards several aspects of chromone chemistry. Selected 2-(N,N-dimethylarnino)chromones have been synthesized via 2-hydroxyacetophenone boron difluoride complex intermediates, and potentiometric analysis of these compounds in ethanolwater has been used to determine the influence of substituents on their basicity. The pKa values have been found to lie within a narrow range (1.92 - 2.52), and the observed substituent effects have been rationalized with the aid of semi-empirical and ab initio molecular orbital calculations. An efficient route has been developed

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31

Søby, Rasmussen Alexander. "En strategisk analyse af Google Chrome = A Strategic Analysis of Google Chrome /." Aarhus : Institut for Økonomi, Aarhus Universitet, 2009. http://mit.econ.au.dk/Library/Specialer/2009/20030904.pdf.

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32

Cheung, Ka-hong. "Chromate toxicity assessment and detoxification by bacteria from the marine environment /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36249890.

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33

McLean, Jeffrey. "Characterization of a chromate-reducing bacterium, potential for a bioremediation application." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0022/MQ51082.pdf.

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34

Little, Laura Grace. "Response of a NEIL1 deficient murine epithelial cell line to chromate." CONNECT TO THIS TITLE ONLINE, 2008. http://etd.lib.umt.edu/theses/available/etd-04172008-090537/.

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35

Cheung, Ka-hong, and 張嘉康. "Chromate toxicity assessment and detoxification by bacteria from the marine environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B45015351.

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36

Babingui, Jean-Paul. "Chromane-2-carboxamides et derives a potentialites antioxydantes et anti-inflammatoires." Nantes, 1993. http://www.theses.fr/1993NANT06VS.

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37

Boukattaya, Fatma. "Addition d'organomagnésiens sur des nitriles fonctionnalisés : application à la synthèse de molécules d’intérêt biologique." Thesis, Le Mans, 2016. http://www.theses.fr/2016LEMA1007.

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L’addition nucléophile des réactifs de Grignard sur les nitriles conduit généralement aux cétones après hydrolyse acide. La double addition, menant à des carbinamines tertiaires après traitement, est beaucoup plus difficile et ne s’effectue habituellement qu’avec les organomagnésiens allyliques. Dans ce contexte, nous avons découvert que les organomagnésiens peuvent effectuer une double addition sur la fonction nitrile des acylcyanhydrines, pour fournir des hydroxyamides. Cette réaction est originale par le fait qu’une large gamme d’organomagnésiens peut être utilisée, dans des conditions part

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38

André, David. "Contribution à l'étude de catalyseurs de fluoration en phase gazeuse du 1,1,1-trifluoro 2-chloroéthane à base d'oxydes de chrome non-stoechiométriques et de chromates et chromites de métaux divalents." Toulouse 3, 1996. http://www.theses.fr/1996TOU30168.

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Les catalyseurs employes pour la fluoration en phase gazeuse par le fluorure d'hydrogene (hf) du 1,1,1-trifluoro 2-chloroethane (f133a) en 1,1,1,2-tetrafluoroethane (f134a), utilise dans les systemes de refrigeration en remplacement du dichlorodifluoromethane (cfc 12) responsable du trou d'ozone stratospherique, sont a base d'oxydes de chrome. Les chromites de metaux de transition (nickel, cobalt, cuivre) et de zinc et magnesium, prepares par combustion, cristallisent sous forme spinelle, mcr#2o#4, et presentent superficiellement du chrome vi qui contribue en partie a l'activite catalytique. L

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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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40

Shervington, L. A. "Studies on a new synthesis of chromans." Thesis, Bucks New University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380298.

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41

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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42

Stern, Heather A. G. (Heather Ann Ganung). "Electrolytic remediation of chromated copper arsenate wastes." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35284.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2006.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Includes bibliographical references.<br>While chromated copper arsenate (CCA) has proven to be exceptionally effective in protecting wood from rot and infestation, its toxic nature has led to the problem of disposal of CCA-treated lumber and remediation of waters and soils contaminated by process wastes. The active ions in water-based CCA are hexavalen

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43

Davidson, Deborah Nicole. "Chemical and spectroscopic studies of chromone derivatives." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1006857.

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Various chromone derivatives have been used in asthma therapy, and their biological activity is apparently related to certain chemical features which include conformation and acidity. In the present study, substituent effects on conformation and acidity have been explored in chromone systems with potential biological activity. A range of variously substituted symmetrical chromone-2-carboxamides (including a series of N,N-dimethylchromone-2-carboxamides) have been prepared via chromone-2-carboxylic acids, which, in turn, were prepared from the corresponding o-hydroxyacetophenones. The N,N-dimet

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Ramaite, Ipfani David Isaiah. "Chemical and spectroscopic studies of chromone derivatives." Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1006888.

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A number of biologically active chromones occur in plants (eg. Khellin) and research in this field has eventually led to the discovery of chromoglycic acid, which is widely used as a sodium salt in asthma therapy. Since biological activity may be related to acidity, a range of chromone-2-carboxylic acids have been prepared via Claisen acylation of substituted o- hydroxyacetophenones and their acid dissociation constants determined potentiometrically to explore substituent effects. From this study it has been found that introduction of certain groups does have a marked effect on acidity. A vari

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45

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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Hoffmann, Thomas. "Modifizierte Flavonoide als neuartige UVA-Schutzmittel Synthese, Untersuchungen zur Photostabilität und zum Singulett-Sauerstoff-Quenchverhalten /." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971538832.

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Detroye, Martine P. M. "Synthèse et caractérisation de carbures de chrome et de carbures mixtes fer-chrome." Doctoral thesis, Universite Libre de Bruxelles, 1999. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211935.

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Long, Jun W., Q. L. Peng, R. Wang, H. W. Zhang, and B. Shi. "Investigation on the release kinetics of chrome from finished chrome tanned leather - 138." Verein für Gerberei-Chemie und -Technik e. V, 2019. https://slub.qucosa.de/id/qucosa%3A34298.

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Content: Chrome tanning is the commonest tanning agent in leather manufacture, and the discard of chrome tanned leather goods inevitably leads to chrome discharge that might have potential environmental risks. In this study, the kinetic behaviors of the release of chrome and organics were investigated by ICP-OES and TOC analyzers respectively. Deionized water was used as medium, and leaching tests were proceed at solid liquid ratio 1:20 as well as rotational speed 60 r/min to simulate the release of chrome tanned leather under natural conditions. The effect of temperature on the behavior kinet

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Kew, Simon James. "Chromic behaviour of aqueous polydiacetylene assemblies." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613811.

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BENSLIMANE, KHALID. "Etude des reactions d'oxydo-reduction des ions chrome 3, chrome 2 et chrome dans les bains fondus a base de chlorures alcalins." Paris 6, 1991. http://www.theses.fr/1991PA066027.

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Ce travail de these a pour objectif d'obtenir des depots de chrome par electrolyse des sels de chrome en bains de sels fondus. Dans ce but une etude fondamentale a ete developpee, qui comprend d'une part la determination des proprietes thermodynamiques des solutions de chrome et d'autre part l'examen des mecanismes reactionnels conduisant au depot de chrome. A partir des mesures de la f. E. M. De la pile de formation chrome-chlore on obtient les caracteristiques thermodynamiques des solutions (enthalpie libre, entropie et enthalpie), ainsi que la solubilite des sels de chrome. L'utilisation de

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