Log in

Relevant bibliographies by topics / Pourbaix diagramy / Dissertations / Theses

To see the other types of publications on this topic, follow the link: Pourbaix diagramy.

Dissertations / Theses on the topic 'Pourbaix diagramy'

Author: Grafiati

Published: 4 June 2021

Last updated: 11 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 21 dissertations / theses for your research on the topic 'Pourbaix diagramy.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Stavinoha, Jakub. "Koroze oceli a hliníku ve vybraných prostředích." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-228957.

Full text

Abstract:

This Master’s thesis is related to corrosion degradation processes on metal surfaces exposed in different environments. The theoretical part is concern with basic principles in electrochemical and atmospheric corrosion. Practical part describes experimentation of corrosion process of aluminium (99,5) and low carbon steel (11321) in two different atmospheric environments. The conclusion of thesis includes evaluations of the results from practical part and comparison with the theoretical part.

APA, Harvard, Vancouver, ISO, and other styles

2

Liu, Lu. "Exploration de la chimie de l'astate en solution : focalisation sur le diagramme de Pourbaix en milieu non complexant et caractérisation de liaisons halogènes induites par l'astate." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2020. http://www.theses.fr/2020IMTA0205.

Full text

Abstract:

L'astate (At, Z = 85) est un élément halogène rare, tous ses isotopes étant radioactifs. En raison des quantités disponibles limitées, aucun outil spectroscopique n'est applicable pour identifier la nature moléculaire des espèces d'At. En conséquence, la chimie de l'At reste méconnue. L'un de ses isotopes, ²¹¹At, est un candidat potentiel pour le traitement de cancers par thérapie alpha ciblée. Cependant, la connaissance limitée de ses propriétés chimiques a entravé les tentatives de marquage de ²¹¹At avec des molécules porteuses ciblant la maladie. Cela a conduit au développement d’un programme de recherches sur la chimie de base de At. Cette thèse s’intéresse plus particulièrement au diagramme de Pourbaix de l’astate et à la caractérisation de liaisons halogènes avec l’espèce AtI, au moyen de divers outils expérimentaux (chromatographie ionique, méthode de compétition et électromobilité). Dans une première partie, des études de spéciation de At en milieu alcalin confirment la présence de l'espèce At⁻ en conditions réductrices. Lorsque le potentiel augmente, l’espèce AtO(OH)₂⁻ se forme. Le changement de spéciation entre ces deux espèces est décrit pour la première fois. Dans une deuxième partie, la formation de liaisons halogènes entre l'espèce AtI et divers composés organiques a été étudiée. La réactivité se résume par une échelle de basicité nouvellement établie dont la force entre le donneur (AtI) et l’atome accepteur varie suivant l’ordre C ≤ O ≤ S (≈ Se)<br>Astatine (At, Z = 85) is a scarce halogen element, all of its isotopes being radioactive. Due to the limited available quantities, no spectroscopic tool is applicable to identify the molecular nature of At species. Consequently, the chemistry of At remains poorly known. One of its isotopes, ²¹¹At, is a potential candidate for the treatment of cancers by targeted alpha therapy. However, the limited knowledge of its chemical properties has hindered attempts to label ²¹¹At with disease targeting carrier molecules. This led to the development of a research program on the basic chemistry of At. This thesis focuses more particularly on the Pourbaix diagram of astatine and the characterization of halogen bonds with the AtI species, by means of various experimental tools (ion chromatography, competition method and electromobility). In the first part, speciation studies of At in alkaline medium confirm the presence of the At⁻ species under reducing conditions. As the potential increases, the AtO(OH)₂⁻ species is formed. The speciation change between these two species is described for the first time. In a second part, the formation of halogen bonds between the AtI species and various organic compounds was studied. The reactivity is summarized by a newly established basicity scale, with the strength between the donor (AtI) and the acceptor atom following the order of C≤ O ≤ S (≈ Se)

APA, Harvard, Vancouver, ISO, and other styles

3

Mogwase, Boitumelo Mmamopedi Sarah. "An electrochemical study of the oxidation of platinum employing ozone as oxidant and chloride as complexing agent / by B.M.S. Mogwase." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9790.

Full text

Abstract:

Motor car exhaust catalysts are some of the most important users of platinum, and much attention is given to the recycling of scrap platinum from spent exhaust systems. The dissolution of platinum from waste exhausts was previously only possible by pyrometallurgical processes or by the use of aggressive chemicals, such as aqua regia and cyanide, all of which, however, cause pollution problems. Recently the potential for the development of hydrometallurgical processes was identified. These processes are more efficient and more environmentally friendly than traditional processes. It was the aim of this study to investigate the oxidation of platinum with ozone as oxidizing agent in the presence of chloride as complexing agent. The influence of various factors, such as chloride ion concentration, pH and temperature were studied thermodynamically and electrochemically in order to achieve efficient leaching. The thermodynamic investigation, leading to the construction of Pourbaix diagrams of platinum in the presence of chloride, confirmed the possibility of the formation of stable aqueous complexes, as well as platinum oxides. From the electrochemical results obtained it can be concluded that ozone may be useful as an oxidizing agent, but according to the leaching results obtained, ozone holds few benefits compared to aqua regia and cyanide, although they still present some environmental challenges. The relatively low percentages of recovery obtained with leaching may be attributed to the rapid decomposition of ozone, which is affected by several factors, such as temperature, pH, initial concentration of ozone, ionic strength and stirring rate. Further optimisation of these factors can possibly prove ozone to be a useful oxidizing agent for the recovery of platinum.<br>Thesis (MSc (Chemistry))--North-West University, Potchefstroom Campus, 2013.

APA, Harvard, Vancouver, ISO, and other styles

4

MOTOKI, YOSHIDA. "Synthesis of Ruthenium-based Water Oxidation Catalysts and Mechanistic Study." Thesis, KTH, Skolan för kemivetenskap (CHE), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-173843.

Full text

Abstract:

Two series of new mononuclear ruthenium complexes with hydrophobic or hydrophilic ligands [Ru(bda)L2] and [Ru(pdc)L3] (H2bda = 2,2'-bipyridine-6,6'-dicarboxylic acid; H2pdc = 2,6-pyridinedicarboxylic acid; L = pyridyl ligands) were synthesized and their electrochemical properties and catalytic activity toward water oxidation were examined. It was revealed that the hydrophobic ligands introduced to [Ru(bda)L2 ] improved the catalytic performance, ahnost twofold TON and TOF values were achieved compared to the [Ru(bda)] catalyst with hydrophilic ligands. The cyclic voltammogram of [Ru(bda)L2] exhibited marginal difference between the catalysts with hydrophobic ligands and hydrophilic ones, implying that the hydrophobic ligands promoted the catalytic activity by :lacilitating formation of a reaction intermediate dimer.

APA, Harvard, Vancouver, ISO, and other styles

5

Ning, Jing. "The Role of Iron Sulfide Polymorphism in Localized Corrosion of Mild Steel." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1476660078407962.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Basly, Jean-Philippe. "Caracterisation de inp par des methodes electrochimiques : spectroscopie d'impedance et methodes potentiostatiques." Caen, 1988. http://www.theses.fr/1988CAEN2002.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Vasquez, Ferdinand. "THE EFFECT OF FREE CHLORINE AND CHLORAMINES ON LEAD RELEASE IN A DISTRIBUTION SYSTEM." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3654.

Full text

Abstract:

Total lead release in drinking water in the presence of free chlorine and chloramine residuals was investigated in field, laboratory and fundamental investigations for finished waters produced from ground (GW), surface (SW), saline (RO) and blended (B) sources. Field investigations found more total lead was released in the presence of chloramines than in the presence of free chlorine for RO and blended finished waters; however, there were no statistical differences in total lead release to finished GW and SW. Laboratory measurements of finished waters oxidation-reduction potential (ORP) were equivalent by source and were not affected by the addition of more than 100 mg/L of sulfates or chlorides, but were significantly higher in the presence of free chlorine relative to chloramines. Development of Pourbaix diagrams revealed the PbO2 was the controlling solid phase at the higher ORP in the presence of free chlorine and Pb3(CO3)2(OH)2(s) (hydrocerussite) was the controlling solid phase in the presence of chloramines at the lower ORP, which mechanistically accounted for the observed release of total lead as PbO2 is much less soluble than hydrocerussite. The lack of differences in total lead release to finished GW and SW was attributed to differences in water quality and intermittent behavior of particulate release from controlling solid films.<br>M.S.<br>Department of Civil and Environmental Engineering<br>Engineering and Computer Science<br>Environmental Engineering

APA, Harvard, Vancouver, ISO, and other styles

8

Addis, Kyle A. "A Corrosion Model for Production Tubing." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1417085983.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Tanupabrungsun, Tanaporn. "Thermodynamics and Kinetics of Carbon Dioxide Corrosion of Mild Steel at Elevated Temperatures." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1355328679.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Champion, J. "Exploration du caractère métallique de l'astate en solution aqueuse." Phd thesis, Université de Nantes, 2009. http://tel.archives-ouvertes.fr/tel-00450909.

Full text

Abstract:

L'alpha-radiothérapie est une technique particulièrement innovante de thérapie des cancers, tout en étant complémentaire des thérapies déjà existantes. Elle repose sur l'utilisation d'un vecteur spécifique (anticorps ou peptide) de la cellule cible à détruire, radiomarqué par un élément radioactif émetteur alpha. L'astate 211 est un candidat particulièrement intéressant compte tenu de l'énergie des particules α qu'il émet et de sa période physique (7,2 h). L'une des voies de marquage envisagée est l'utilisation de l'astate à un degré d'oxydation supérieur à zéro en tant que cation. En effet, l'astate est supposé présenter un caractère plus métallique que les autres halogènes du fait de son positionnement dans le tableau périodique. Cette voie de marquage a été peu abordée dans la littérature en raison du manque de données sur la chimie de l'astate aux degrés d'oxydation supérieurs à zéro. Le but de ce travail était donc d'explorer cette propriété de l'astate via la construction du diagramme Eh, pH (ou diagramme de Pourbaix) en milieu aqueux non complexant. Pour ce faire, ce travail s'est appuyé sur une double approche expérimentale / théorique. L'approche expérimentale utilise des méthodes dites de compétition pour identifier les espèces formées et les constantes thermodynamiques des équilibres étudiés. L'approche théorique utilise des méthodes de chimie computationnelle et fournie des informations à l'échelle moléculaire sur les systèmes étudiés afin de prédire les données thermodynamiques qui servent de support et complément à l'approche expérimentale. Un résultat important de ce travail montre la présence de deux espèces cationiques stables de l'astate en solution aqueuse, At+ et AtO+.

APA, Harvard, Vancouver, ISO, and other styles

11

Sutter, Eliane. "Contribution a l'etude de la reactivite de la surface du titane en solution acide." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13131.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Zhang, Wei. "Initiation and Propagation of Localized Corrosion of Mild Steel in Marginally Sour Environments." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1605039352183903.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Robouch, Piotr. "Contribution a la prevision du comportement de l'americium, du plutonium et du neptunium dans la geosphere, donnees chimiques." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13230.

Full text

Abstract:

Etude de l'hydrolyse de l'am. Solubilite de am::(2)(co::(3))::(3) en milieu naclo::(4) 3m ; seuls les complexes am (co::(3))::(i)**(3-i) ont ete trouves. Calcul des constantes de stabilite. Formation de complexes entre am et les matieres humiques. Mesure de la solubilite de puo::(2)co::(3) en milieu hco::(3)**(-)/naclo::(4). Diagrammes de pourbaix, utiles pour la speciation de np, pu et am dans differentes eaux naturelles souterraines

APA, Harvard, Vancouver, ISO, and other styles

14

Gao, Shujun. "Thermodynamics and Kinetics of Hydrogen Sulfide Corrosion of Mild Steel at Elevated Temperatures." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1528836064560164.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Sun, Yi-Pin, and 孫依嬪. "Pourbaix Diagrams Study of Electrochemical Prepared Manganese Oxides." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/15526588522720703089.

Full text

Abstract:

碩士<br>國立暨南國際大學<br>應用化學系<br>94<br>One-dimensional tunnel-structured manganese oxides have been intensively investigated for several decades because of their economic value and potential applications in molecular sieve, catalyst of fuel cell and cathode material of lithium ion battery. The structure of resultant manganese oxides is very sensitive to the synthetic routes. This research has demonstrated a room temperature electrochemical synthesis in preparing α- octahedral molecular sieve. The correlations between Pourbaix diagram and counter ion were investigated. The dependence of structure on the pH vale, potential and counter ions were observed.

APA, Harvard, Vancouver, ISO, and other styles

16

CHENG, HSU, and 鄭旭. "First-principles study on pourbaix diagram of metal oxides." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/3k5zz7.

Full text

Abstract:

碩士<br>國立中正大學<br>物理系研究所<br>106<br>Pourbaix diagram is useful for understanding corrosion condition of metals in specific environment. In this thesis, we use an efficient scheme which combine first principle calculation of solids with experimental Gibbs free energies of arbitrary aqueous states. Using this scheme, we will construct the Potential/pH diagrams (Pourbaix diagrams) for Mn, Fe and Al. We will also study the effect of doping of CaO on the Potential/pH diagrams of ceramic materials(Al2O3).

APA, Harvard, Vancouver, ISO, and other styles

17

Palazhchenko, Olga. "Pourbaix diagrams at elevated temperatures: a study of Zn and Sn." Thesis, 2012. http://hdl.handle.net/10155/276.

Full text

Abstract:

Metals in industrial settings such as power plants are often subjected to high temperature and pressure aqueous environments, where failure to control corrosion compromises worker and environment safety. For instance, zircaloy (1.2-1.7 wt.% Sn) fuel rods are exposed to aqueous 250-310 oC coolant in CANDU reactors. The Pourbaix (EH-pH) diagram is a plot of electrochemical potential versus pH, which shows the domains of various metal species and by inference, corrosion susceptibility. Elevated temperature data for tin +II and tin +IV species were obtained using solid-aqueous phase equilibria with the respective oxides, in a batch vessel with in-situ pH measurement. Solubilities, determined via spectroscopic techniques, were used to calculate equilibrium constants and the Gibbs energies of Sn complexes for E-pH diagram construction. The SnOH3+ and Sn(OH) species were incorporated, for the first time, into the 298.15 K and 358.15 K diagrams, with novel G ͦ values determined at 358.15 K.<br>UOIT

APA, Harvard, Vancouver, ISO, and other styles

18

Chu, Yi-Min, and 朱益民. "First-Principles Studies of GaN/Ga2O3 Heterointerfaces and Pourbaix Diagrams for Ga2O3." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/4q9jvh.

Full text

Abstract:

碩士<br>國立中興大學<br>精密工程學系所<br>101<br>First-principles calculations were used to determine the heteroepitaxial growth behavior of GaN (0001) on Ga2O3(-201) templates and the Pourbaix diagram of Ga2O3. The relative stability of eight different models of the GaN(0001)/Ga2O3(-201) interface is examined as a function of the valence band offset. The most favorable interface consists of N─Ga bonds at the GaN(0001)/Ga2O3(-201) interface. This interface structure agree with previously reported experimental and theoretical results of the surface treatment of N exposure on the Ga2O3 surface. The potential and pH relationships of Ga2O3 systems in aqueous solutions were obtained from Nernst equation and thermodynamic equations. Our results agree with experimental Pourbaix diagrams of Ga2O3.

APA, Harvard, Vancouver, ISO, and other styles

19

Lin, Chih-wei, and 林子瑋. "Phase equilibria, Pourbaix diagram and corrosion properties of dental-arch-wire-used shape memory alloys." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/q3fqkt.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Medupe, Elizabeth. "An electrochemical investigation of the dissolution of platinum employing AICI3/HNO3 / Elizabeth Medupe." Thesis, 2014. http://hdl.handle.net/10394/15413.

Full text

Abstract:

Industrial activities of mankind are feared to damage the environment irretrievably. Especially the release of huge amounts of harmful gases causes concern. In this regard the environmental pollution caused by the one billion motor vehicles on earth is particularly important. The platinum-group metals (PGM) are well known for their catalytic activity. They are used extensively for reducing the amounts of hydrocarbons, carbon monoxide and nitrogen oxides from the exhausts gas emitted by automobiles. In 2012 20% of platinum and 27% of palladium produced were used in the manufacture of catalytic converters. With the increasing use of PGM-containing autocatalysts, the reclaiming of PGMs from spent catalysts has become essential. Particularly attractive hydrometallurgical methods are those based on the use of halide ions e.g. sodium chloride, as complexing agent in conjunction with nitric acid as oxidant. The chemical reactions between mixtures of aluminium chloride and nitric acid have been studied, but the electrochemical reactions have received little attention. The research reported in this dissertation is aimed at providing data relating to the electrochemical behaviour of platinum in mixtures of aluminium chloride and nitric acid. The construction of Pourbaix diagrams of platinum in chloride environments confirmed that the stable chloro-complexes [PtCl4]2- and PtCl6]2-, as well as platinum oxides (PtO and PtO2) could play a role under the experimental conditions employed in this study. From the thermodynamic results it can be concluded that the systems deserving consideration favour high chloride concentrations and high temperatures. Notable anodic reactions found were the adsorption of chloride on the platinum surface and the gradual formation of [PtCl6]2-, followed by the formation of platinum oxides at 1.00 to 1.01 V. The results show that anodic currents diminished with lower chloride concentrations. A seemingly anomalous anodic behaviour at 35 °C and 45 °C could be explained in terms of a competition between platinum oxide formation and the formation of platinum chloro-complexes. Evidence for the following cathodic reduction reactions was found: hydrogen evolution, reduction of dissolved oxygen to hydrogen dioxide (-1.3 V SHE), nitrate ion reduction to nitrite ions (-0.01 V SHE), nitrite ion reduction to nitric oxide (-0.85 V SHE) and reduction of PtO and PtO2 to Pt (at -1.00 V and 1.01 V SHE, respectively). A brief study was undertaken in an attempt to relate the electrochemical results to the leaching of platinum from a virgin automotive exhaust catalyst. The recovery was low for mixtures with low chloride concentrations, which could be expected from the electrochemical polarisation curves obtained in electrolytes with different chloride concentrations. The maximum platinum recovery attained, was 60% at 45 °C in a mixture containing 0.6 M AlCl3 and 0.9 M HNO3.<br>MSc (Chemistry), North-West University, Potchefstroom Campus, 2014

APA, Harvard, Vancouver, ISO, and other styles

21

SHU-YI, CHU, and 朱書儀. "Theoretical Pourbiax Diagrams of Ru-Polypyridyl Complexes: A Innocent and Non-innocent Ligand Comparison for Water Oxidation Catalysis." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/28930637507261564334.

Full text

Abstract:

碩士<br>國立臺灣師範大學<br>化學系<br>102<br>Water oxidation is a key half-reaction (2H2O → O2 + 4H+ + 4e−) employed in solar-fuel-based energy conversion, and it is dominated by proton-coupled electron transfer (PCET), given its multi-electron, multi-proton character. Mononuclear Ru-based water oxidation catalysts (WOCs) are a valuable class of WOCs used for water splitting. Noninnocent ligands (NILs) have three oxidation states, NILOx, NIL•, and NILRed, that have an electron redox transformation in common. NILs can help disperse the electron density at the metal center and keep the metal center in low oxidation states. The Tanaka catalyst, an anthracene-bridged dinuclear Ru complex, is an interesting example of a Ru–NIL framework in catalysis. We used density functional theory to calculate pKa and the standard reduction potential of Ru(OH2)(tpy)(tBu2Qn), Ru(OH2)(tpy)(Bpm), and Ru(OH2)(tpy)(Bpy) (tBu2Q = 3,5-di-tert-butyl-2,2-benzoquinone, tpy = 2,2':6',2″-terpyridine, Bpm = 2,2'-bipyrimidine, and Bpy = 2,2'-bipyridine) complexes, and we then constructed the Pourbaix diagram to compare innocent ligands and NILs. We focused on pH-dependent onset catalytic potentials indicative of a PCET-driven low-energy pathway for the formation of products with an O−O bond and investigated the differences between these complexes by using the Pourbaix diagram. We found a lower [RuIV=O]/[RuV=O] couples potential in the solvation model density (SMD) system and a new intermediate complex [RuIII(3αO•-)(tpy)(βSQ)]+ that can promote radical-radical coupling to form an O−O bond. In addition, we used different computational methods to compare the differences and to achieve better performance in the SMD system.

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!