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Tesi sul tema "Cobalt compounds"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 28 gennaio 2023

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1

Ng, Jesse B. "Mono- and binuclear cobalt hydrides". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30789.

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The homogeneous hydrogenation of arenes with functional groups was studied with allylcobalt complexes containing the bulky chelating diphosphines dippp (1,3-bis(diisopropylphosphino)propane and dippcyp (trans-(±)-l,2-bis(diisopropylphos-phino)cyclopentane). The results indicated that these catalyst precursors were unsuitable for the hydrogenation reactions, being too sensitive to the nature of the substrate. From these hydrogenation reactions, the intermediates (η⁵-cyclohexadienyl)Co(dippcyp) (10) and (η⁴-2-methoxynaphthalene)Co(H)(dippcyp) (11) were isolated and structurally characterized, thus providing some insight into the mechanism of the hydrogenation reaction. The production of binuclear hydrides such as [(dippp)CoH₂]₂ (4) and [(dippcyp)CoH₂]₂ (9) was observed to lead to the end of the catalysis. An X-ray structural characterization of the blue hydride [(dippp)CoH₂]₂ (4) showed that in the solid state it is binuclear. Although the complex is diamagnetic in the solid state (6-280 K), in solution its paramagnetic behaviour could only be attributed to an equilibrium with a second species proposed to be mononuclear, (dippp)CoH₂. In addition, a cyclic voltammogram of the complex in solution indicated that the predominant species still was the binuclear compound [(dippp)CoH₂]₂ (4). One of the syntheses of [(dippp)CoH₂]₂ (4) gave a product identified as (dippp)CoH₃ (5). Based on variable-temperature spin-lattice relaxation time (T₁) measurements and an electrochemical study, this red hydride complex appeared to contain an η²-H₂ ligand. The relationship of this complex with the blue hydride apparently involves the mononuclear species, (dippp)CoH₂. Independent pathways led to the formation of both the blue and red hydrides, and these pathways are discussed in terms of possible mechanisms.
Science, Faculty of
Chemistry, Department of
Graduate

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2

Cooke, Michael D. "Magnetostrictive properties of polycrystalline iron cobalt films". Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340249.

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3

DuPont, Julie A. "The coordination chemistry of thioether-supported, low-valent cobalt complexes". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 3.92 Mb., 165 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3200521.

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4

Liao, Lexiang. "Cobalt site preferences in iron rare-earth based compounds". Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=39786.

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This thesis presents the first systematic study of the cobalt site preferences in iron rare-earth based compounds. The Mossbauer source technique employed in this work offers a direct and unambiguous way to quantitatively determine cobalt site preferences in these compounds at extremely low cobalt contents. Data quality as well as counting efficiency for the source ($ sp{57}$Co doped) samples is enhanced by constructing a resonant conversion electron detector utilising 90% $ sp{57}$Fe enriched stainless steel foil. Our results have produced the most convincing evidence that cobalt substitutes preferentially for iron in these compounds. We have demonstrated that the site volume is the dominant factor controlling the preferential cobalt substitutions at transition-metal sites with volume $<$12.2A$ sp3$. The cobalt preference for a site decreases linearly with increasing site volume at a rate of $ sim$0.9A$ sp{-3}$. In general, cobalt shows a preference for sites with volume $<$11.8A$ sp3$. As site volume becomes sufficiently large ($ ge$12.2A$ sp3$), the negative enthalpy of mixing between cobalt and rare-earth plays a significant role in modifying the cobalt site preferences in combination with the site volume effects. This results in cobalt preferring strongly those sites with the highest number of rare-earth nearest-neighbors.

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5

尹業高 e Yegao Yin. "The preparation and structure determination of some copper, cobalt, iron and manganese complexes and the study of their properties". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31235463.

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6

Yin, Yegao. "The preparation and structure determination of some copper, cobalt, iron and manganese complexes and the study of their properties /". Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19668570.

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7

Xiao, Jie. "Layered lithium nickel manganese cobalt dioxide as a cathode material for Li-ion batteries". Diss., Online access via UMI:, 2008.

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8

Wang, Hongli. "A study of the structural, microstructural and magnetic properties of iron-platinum and cobalt-platinum type nanoparticles". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 200 p, 2007. http://proquest.umi.com/pqdweb?did=1354136761&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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9

Doddridge, Bruce Germein. "Ligand exchange and substitution on five-coordinate complexes of copper (II), nickel (II) and cobalt (II) /". Title page, contents and summary only, 1986. http://web4.library.adelaide.edu.au/theses/09PH/09phd641.pdf.

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10

Mitchell, Glenn Antony. "Thermal behaviour of some cobalt (II) carboxylates and related compounds". Thesis, University of Huddersfield, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357725.

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11

Yang, Kaiyuan. "Substitution Chemistry of the Cobalt Complexes [Co₂(CO)₆(PhC≡CR) (R=Ph, H) and PhCCo₃(CO)₉] with the Diphosphine Ligands [Bis(diphenylphosphino)maleic Anhydride (BMA) and (Z)-Ph₂PCH=CHPPh₂]. Reversible Chelate-to-Bridge Diphosphine Ligand Exchange, Phosphorus-Carbon Bond Cleavage and Phosphorus-Carbon Bond Formation". Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc279206/.

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The tricobalt cluster PhCCo3(CO)9 (1) reacts with the bidentate phosphine ligand 2,3-bis(diphenylphosphino)maleic anhydride (bma) in the presence of added Me3NO to give the diphosphine-substituted cluster PhCCo3(CO)7(bma) (2). Cluster 2 is unstable in solution, readily losing CO to afford Co3(CO)6[(μ2-η2/η1-C(Ph)C=C(PPh2)C(O)OC(O)](μ2-PPh2) (3) as the sole observed product. VT-31P NMR measurements on cluster 2 indicate that the bma ligand functions as both a chelating and a bridging ligand. At -97 °C, 31P NMR analysis of 2 reveals a Keq of 5.7 in favor of the bridging isomer. The bridged bma cluster 2 is the only observed species above -50°C. The solid-state structure of 2 does not correspond to the major bridging isomer observed in solution but rather the minor chelating isomer. The conversion of 2 to 3 followed first-order kinetics, with the reaction rates being independent of the nature of the reaction solvent and strongly suppressed by added CO, supporting a dissociative loss of CO as the rate-determining step. The activation parameters for CO loss were determined to be ΔH≠ = 29.9 ± 2.2 kcal/mol and ΔS≠ = 21.6 ± 6 eu.

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12

Shay, Daniel Travis. "Synthesis, structure, and reactivity of terminal cobalt imido complexes". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 134 p, 2007. http://proquest.umi.com/pqdweb?did=1257806121&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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13

Jack, J. James. "Properties of CH bonds in cobalt, tin and zinc alkyl compounds". Thesis, University of Aberdeen, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287607.

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This thesis describes the results of a detailed vibrational study on a series of mainly methyl, but also certain ethyl containing organometallic compounds. The primary objective of the work is to show that 'isolated CD' frequencies, v^isCD measured from a CH₂D group, can be used to provide predictions of CH bond parameters (CH bond length (r_oCH), HCH bond angle (αHCH) etc.) equally as well as 'isolated CH' frequencies, v^isCH measured from a CHD₂ group. From a review of spectroscopic data in the literature it is apparent that v^isCD, can be linearly related to v^isCH. The 98% correlation coefficient for the v^isCD versus v^isCH plot illustrates the existence of a workable linear relationship. Clearly the existence of such a relationship seems to suggest that the isotopic substitution CH₂D removes Fermi and other resonance effects almost as well as the CHD₂ isotopic substitution. Moreover, correcting the v^isCD frequency for the effects of anharmonicity using a variable R correction factor with a maximum variation 0.5% from 1.011 gives a much improved fit. Making use of existing linear correlations between v^isCH and fundamental CH bond parameters (r_oCH and αHCH), it has been shown that the determination of the v^isCD frequency can be used to provide useful predictions of r_oCH and αHCH. All this can be achieved without the need for deuteration of ligand CH sites, even in complex systems, previously necessary in the determination of v^isCH frequencies. The CH/CD stretching regions for a series of eight methylpyridinatocobaloxime isotopomers have been studied, frequencies assigned and the geometry of the methyl group determined.

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14

Potratz, Christopher M. "The Synthesis, Structure and Characterization of Extended Cobalt Ruthenium Carbonyl Compounds". The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275413923.

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15

Chen, Loren. "Syntheses, characterization and reactivity studies of some phosphido-bridged cyclopentadienyl cobalt(II) bimetallic complexes /". The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487261553059417.

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16

Connaway, Melissa Clare. "Design and characterization of zeolite supported cobalt carbonyl catalysts". Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/82894.

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Transition metal compounds such as Co₂(CO)₈ have often been used to catalyze various organic reactions. Severe difficulties may be encountered when attempts are made to recover and separate the soluble catalysts. A heterogeneous system consisting of Co₂(CO)₈ impregnated on zeolites with faujasitic structure has been designed and investigated using a variety of techniques. In situ FTIR spectroscopy and carbon monoxide evolution were used to identify the major products generated, namely Co₄(CO)₁₂ and Co(CO)_4^-. Disproportionation may be induced thus forming Co(CO)_4^- and an associated cation from the supported subcarbonyls by addition of various ligands such as methanol. The location of the supported cobalt carbonyls is determined by their reactivity toward various phosphines with various kinetic diameters. The materials prepared in this manner were found to be active in catalyzing the methanol carbonylation reaction and following thermolysis were also found to be active Fischer-Tropsch catalysts. Major products observed in the carbonylation of methanol were methyl acetate and an acetaldehyde dimethyl acetal. The supported cobalt catalyst displays greater activity than Co₂(CO)₈ in solution for the carbonylation reaction when conducted under similar conditions. In the Fischer-Tropsch process, selectivity is seen for the production of linear, short-chain hydrocarbons.
Ph. D.

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17

Dana, Bogden Hariton, e n/a. "Pyridylacetylenes and their cobalt clusters; novel naphthalimide monomers and polymers". University of Otago. Chemistry Department, 2005. http://adt.otago.ac.nz./public/adt-NZDU20060707.142806.

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A series of 2,6- and 3,5-ethynylpyridyl compounds and their cobalt clusters have been prepared and analysed in Chapter 2, in order to study through-space and through-bond interactions between the ethynyl arms. Bidentate N- donor ligands, such as bipyridine and o-phenanthroline with alkyne functionality have been used extensively as building blocks for a wide range of molecular materials, but monodentate ethynylpyridyls have received less attention. The results showed that while there is no orbital restriction on a RC[triple bond]C-n-[pi]�cc-C[triple bond]CR through-bond interaction in 2,6-ethynylpyridyls, no significant interaction exists. Nevertheless, there are intramolecular interactions as manifested in the distortions which occur in the solid state structure of the compounds and the lability of the diphenylphosphine methane (dppm) moieties in the oxidised Co₂(CO)₄dppm species. Polymerisation by Sonogashira coupling between dibromo pyridines or diiodo ferrocene and ethynyl pyridines resulted in only oligomeric fractions that could be separated. The thesis also reports the synthesis and characterization of some novel naphthalimide monomers with acrylic and allyl headgroups. The naphthalimide moiety is substituted in the 4-position with various functionalities. This is presented in detail in Chapter 3 of the thesis. The monomers� structure is the following: [illustration omitted] wherein: A may be a polymerizable group (methacrylate or allyl), which includes a spacer entity (aliphatic or aromatic); B is selected from an ethenyl or ethynyl linked organometallic group, a halogen and/or an amine (i.e. bromo, ethynylferrocene, ethenylferrocene, trimethylsilylethynyl, nitro, piperidine and ethenylpiperidine). The acrylic monomers were synthesized by coupling 4-bromo-1,8-naphthalic anhydride with an amino alcohol to give an imide, which then was coupled with methacryloyl chloride to provide the methacrylate. Functionalization in the 4-position of the naphthalimide moieties was achieved by Sonogashira and Heck coupling reactions with for example ethynylferrocene, trimethylsilyl acetylene, vinylferrocene. For the allyl monomers synthesis, a reaction between allyl amine and 4-Bromo-naphthalic anhydride provided 4-bromo-naphthalimido allyl, which was then functionalized by further Sonogashira and Heck coupling reactions. The monomers were polymerised and copolymerised with other widely used comonomers, such as methyl methacrylate, methyl acrylate, styrene, vinyl carbazole and acrylonitrile. The polymerisation processes and the full analyses of the (co)polymers are described in Chapter 4. Free radical polymerisation, FRP, initiated by azo bisisobutyronitrile, AIBN at elevated temperature was the main technique employed for making the (co)polymers. Atom Transfer Radical Polymerisation, ATRP was conducted for some monomers although the results were inconclusive (the yields were low, under 50%, but the molecular weight distributions were quite narrow, PDI�s <1.7). Heck coupling polymerisation was performed for the bromo- substituted methacrylic and allyl monomers and supplied colorful, well-defined polymeric materials, with low polymerisation degrees. All polymers were analyzed by HPLC, NMR, UV-VIS, IR, electrochemistry and fluorescence. The (co)polymers made by FRP had various molecular masses (Mn = 3000- 90.000), whereas the polydispersities were PDI = 1.4- 4.6. Most of the (co)polymers were fluorescent and had good thermal and electrochemical properties. Potential applications of the polymers have been suggested and relevant literature background in the field is provided in both Chapters 1 and 4. The monomers/ polymers are stable compounds (no special storage conditions required) and can act as good candidates for potential applications in light emitting devices, as resins/ binders for coating materials, in the dyes and pigment industry and also for manufacturing of conducting polymers and/or composite materials.

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18

Summers, Jack S. "Reactions of macrocyclic legand complexes of low valent nickel and cobalt with carbon dioxide : the preparation, characterization, and reactivity of a novel carbon dioxide adduct of cobalt". Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/27283.

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19

Filipczyk, Grzegorz Paweł. "Ferrocenyl-Alkynes and Butadiynes: Reaction Behavior towards Cobalt and Iron Carbonyl Compounds". Doctoral thesis, Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-231913.

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Die vorliegende Dissertation beschreibt die Synthese und Charakterisierung von neuartigen perferrocenylierten, cyclischen Komplexen unter Anwendung der Cobalt-vermittelten Cyclomerisierung in Kombination mit einer C-H-Bindungsaktivierung als auch die Bildung von ferrocenylierten Phosphinoalkinid-Komplexen mit Eisen- und Cobaltcarbonylen. Die elektrochemischen Eigenschaften und die Elektronentransfer-prozesse zwischen den terminalen Ferrocenyleinheiten in den unterschiedlichen cyclischen Verbindungen wurden unter Einbeziehung der Struktur/chemischen Zusammensetzung der Brückenbausteine ermittelt. Elf perferrocenylierte, cyclische Komplexe wurden mittels [2+2] bzw. [2+2+2] Cyclomerisierung von 1,4-Diferrocenylbutadiin FcC≡C–C≡CFc (Fc = Fe(η5-C5H4)(η5-C5H5)) unter Verwendung von Dicarbonylcyclopentadienylcobalt Co(η5-C5H5)(CO)2 erhalten. Diese können in drei Gruppen unterteilt werden: (i) Produkte der Cyclodimerisierung mit zusätzlicher Kettenverlängerung, welche Cyclobutadienyl-einheiten als zentrale Brückenbausteine besitzen (3a,b und 4a,b), (ii) Produkte der Cyclodimerisierung mit gleichzeitiger CO-Insertion (6a,b,c und 7), und (iii) Produkte der Cyclotrimerisierung gefolgt von einem Ringschluss durch eine C-H-Bindungsaktivierung (5a,b,c). Die Optimierung der Reaktionsbedingungen wurde zur Ausbeutemaximierung der jeweiligen Verbindungsfamilien durchgeführt. Ein weiterer Teil dieser Forschungsarbeit bezieht sich auf die verschiedenen Reaktionsmuster von (Ferrocenylethinyl)diphenylphosphan- mit zweikernigen Eisen- bzw. Cobaltcarbonylverbindungen in Form von Dieisennonacarbonyl und Dicobaltoctacarbonyl als Reagenzien. Dabei konnten sechs gemischte Carbonyl- und Ferrocenyl-funktionalisierte Phosphinoacetylid-Komplexe mit Eisen(0) und Cobalt(0) erhalten und charakterisiert werden
The present PhD study focuses on the synthesis and characterization of novel perferrocenylated cyclic complexes utilizing cobalt - mediated cyclomerization in combination with C–H bond activation as well as formation of ferrocenylated phosphino-alkyne compounds with iron and cobalt carbonyls. Electrochemical properties and electron-transfer processes between terminal ferrocenyl units in the diverse cyclic compounds are explored in relation to the chemical composition of the building blocks connecting them. Eleven perferrocenylated cyclic compounds were obtained via [2 + 2] and [2 + 2 + 2] cyclomerization of 1,4-diferrocenylbutadiyne FcC≡C–C≡CFc (Fc = Fe(η5-C5H4)(η5-C5H5)) by the reaction with dicarbonylcyclopentadienylcobalt Co(η5-C5H5)(CO)2. They are subdivided into three groups: (i) products of cyclodimerization with additional chain extension, possessing cyclobutadienyl moieties as a central linkage unit (3a,b and 4a,b), (ii) products of cyclodimerization with consecutive CO insertion (6a,b,c and 7), and (iii) products of cyclotrimerization followed by cycle formation via C–H bond activation (5a,b,c). Optimization of the reaction conditions was made in order to maximize the amount of each group of compounds. Furthermore, another part of this research work focuses on diverse reaction patterns of (ferrocenylethynyl)diphenylphosphane with diironnonacarbonyl and dicobaltocta-carbonyl. Six mixed carbonyl and ferrocenyl-functionalized phospinoalkynyl compounds of iron(0) and cobalt(0) were obtained and characterized

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20

Chhabra, Anil Kumar. "A novel squid calorimeter and its application to some intermetallic cobalt compounds". Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37660.

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21

Bediako, Daniel Kwabena. "The Electrocatalytic Evolution of Oxygen and Hydrogen by Cobalt and Nickel Compounds". Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17467226.

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In order to meet the ever-increasing demand for energy, a worldwide transition away from fossil fuels to renewable solar–fuels is required. However, the intermittency of local insolation mandates a cost-effective and efficient storage scheme. Using solar-derived electricity to drive the thermodynamically uphill water splitting reaction to generate dihydrogen and dioxygen is one promising method of storing solar energy in fuels. This “artificial photosynthesis” scheme requires the execution of two half-reactions, one involving the oxidation of water to O2—the oxygen evolution reaction (OER)—and the other entailing the reduction of hydrogen ions to H2—the hydrogen evolution reaction (HER). Accomplishing these electrocatalytic reactions stresses the development of catalysts that are capable of mediating reactions that are in net multi-electron, multi-proton transformations. Transition metal oxides are known to be promising candidates for mediating the OER and their electrocatalytic properties have been studied extensively and optimized for operation at pH extremes. In contrast, intermediate pH OER has been relatively underexplored and the influence of proton-coupled electron transfer (PCET) reactions on OER kinetics of these materials at close-to-neutral pH has for long remained unclear. The OER studies described here have focused on elucidating the underlying mechanistic basis for the catalytic behavior of a class of structurally disordered first-row transition metal oxides, with an emphasis on intermediate-pH catalysis and proton–electron coupling. At a fundamental level, understanding how protons and electrons may be managed and coupled to engender improved activity remains of great importance to the design of new electrocatalysts. To this end, the synthesis and study of homogeneous HER catalysts bearing functional groups in the second coordination sphere that can modulate proton–electron coupling is particularly interesting. The HER studies presented here discuss this important issue within the context of metalloporphyrin catalysts possessing proton relays.
Chemistry and Chemical Biology

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22

Meyer, Todd Roland. "Studies on selectivity in the Pauson-Khand reaction and synthesis of an intermediate of isocarbacyclin". Diss., Montana State University, 2005. http://etd.lib.montana.edu/etd/2005/meyer/MeyerT0805.pdf.

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23

Wong, Heng Vee. "Structural, electronic and kinetic studies on organometallic intercalates of metal dichalcogenides". Thesis, University of Oxford, 1993. http://ora.ox.ac.uk/objects/uuid:aad80a5e-a1bb-4eea-80e8-ce079e0b1204.

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Large single crystals of the metal dichalcogenide hosts ZrS2 and 811X2 (X = S, Se) have been successfully intercalated with a variety of organometallic guests {C0(η-C5H5)2, CO(η-C5H4CH3)2, Mo(η-C6H6)2, Mo(η-C7H7)(η-C5H5), W(η-C7H7)(η-C5H5), Ti(η-C8H8)(η-C5H5)}. The structural and electronic properties of these materials have been studied, as well as the intercalation kinetics of these organometallic species into the tin dichalcogenides. X-ray and neutron diffraction experiments have been used to obtain 001 reflections in order to obtain a one-dimensional profile of electron and neutron scattering in these disordered layered materials (Chapter Two). Refinement of the data shows that for all the organometallic guests, the majority of the intercalant adopts an orientation in which the principal molecular axis lies parallel to the layer planes of the host. These findings are confirmed by 2H NMR spectroscopy on single crystals of deuterated cobaltocene intercalates of ZrS2 and SnSe2, where it has been shown that rapid C5, but not C2, rotation of the metallocene occurs in the interlamellar van der Waals space. To study the electronic properties of these intercalates, electrical resistivity and magnetic susceptibility measurements have been performed (Chapter Three). An apparatus has been built to measure the resistivity of these crystal intercalates down to 4.2K. The resistivity measurements show that intercalation of various organometallic complexes confers metallic properties upon ZrS2 while SnS2{Co(η-C5H5)2} 0.3 becomes a superconductor with a Tc of 8.3K. The magnetic susceptbility measurements confirm the presence of guest-host charge transfer. Estimates of its extent, as well as the magnitude of the Pauli susceptibility in these intercalates, have been attempted. Studies on the rate and mechanism for the intercalation of cobaltocene into the disulfides and diselenides of tin have been performed (Chapter Four). An apparatus has been designed and constructed for in situ diffraction using synchrotron X-rays in order to monitor the progress of these rapid intercalation reactions. The results indicate that the rate of intercalation of cobaltocene into the tin dichalcogenides is very much dependent on the solvent used, being significantly faster in dimethoxyethane than in toluene. Analyses of the kinetic rate expressions for the tin dichalcogenide intercalation in dimethoxyethane suggests that diffusion of cobaltocene molecules into the interlamellar space constitutes the rate limiting step. The choice of solvent also dramatically affects the mechanism of the intercalation. When a solution of cobaltocene in dimethoxyethane is used, the host transforms directly to the final product but in toluene, staged intermediates are observed during the intercalation process. The apparatus and techniques that have been developed for the in situ kinetics experiments are general and permit dynamic structural transformations in air- and moisture-sensitive suspensions of solids to be effectively studied.

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24

Muñoz, Trinidad. "Synthesis, structure and redox reactivity of Co₃(CO)₆(μ₂-η²,η¹-C(Ph)C=C(PPH₂)C(O)SC(O)) (μ₂-PPh₂)". Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc279408/.

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The tricobalt cluster PhCCo₃(CO)₉ (1) reacts with the bidentate phosphine ligand 2,3-bis(diphenylphosphino)maleic thioanhydride (bta) with added Me₃NO to yield PhCCo₃(CO)₇(bta) (2), which upon heating overnight yields Co₃(CO)₆(μ₂-η²,η¹-C(Ph)C=C(PPH₂)C(O)SC(O)) (μ₂-PPh₂) (3). Cluster (3) has been isolated and characterized by FT-IR and ³¹P NMR spectroscopy. Structural determination of the cluster has been demonstrated by X-ray diffraction analysis. Cluster (3) is analogous to the cluster synthesized by Richmond and coworkers. The redox properties of (3) have been examined by cyclic voltammetry and the data are reported within.

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25

Kung, Irene Yuk Man. "Part I, Cobalt thiolate complexes modeling the active site of cobalt nitrile hydratase ; Part II, Formation of inorganic nanoparticles on protein scaffolding in Esherichia coli glutamine synthetase /". Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/8647.

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26

Neveling, Arno. "Preparation of new rhodium and cobalt complexes as catalysts for hydroformylation studies". Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/49777.

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27

Xu, Xiaoshan. "The magnetism of free cobalt clusters measured in molecular beams". Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-02202007-114848/.

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Thesis (Ph. D.)--Physics, Georgia Institute of Technology, 2007.
de Heer, Walter A., Committee Chair ; Chou, Meiyin, Committee Member ; Whetten, Robert L., Committee Member ; First, Phillip N., Committee Member ; Pummer, Earl Ward, Committee Member.

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28

Cripps, Chala Ann. "Synthesis and characterization of cobalt ferrite spinel nanoparticles doped with erbium". Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/30855.

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29

Walther, Till [Verfasser]. "Magnetoelectric composite ceramics of barium titanate and cobalt-iron compounds : [kumulative Dissertation] / Till Walther". Halle, 2018. http://d-nb.info/1163274631/34.

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30

Altahan, Mohammed Abdulredha. "Cobalt(III), copper(II), and nickel(II) coordination compounds as cations in polyborate chemistry". Thesis, Bangor University, 2017. https://research.bangor.ac.uk/portal/en/theses/cobaltiii-copperii-and-nickelii-coordination-comppounds-as-cations-in-polyborate-chemistry(ba5f189b-2229-481f-9d8d-0bdce17903a8).html.

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Abstract (sommario):

This thesis describes the synthesis and characterization of a number of polyborate compounds containing transition metal complex cations; most of these compounds contain 6-membered B3O3 boroxole rings within their structures. A total of twenty-six transition metal complex polyborate salts are reported: one contains the triborate monoanion, [B3O3(OH)4]-, three contain the tetraborate dianion [B4O5(OH)4]2-, twelve contain the pentaborate anion, [B5O6(OH)4]-, three contain the hexaborate dianion, [B6O7(OH)6]2- and five contain heptaborate anions (three of which are [B7O9(OH)5]2-, and two are [B7O9(OH)6]3-). Additionally, two compounds contain two isolated polyborate anion species (octaborate dianion [B8O10(OH)6]2- with pentaborate anion [B5O6(OH)4]-, and triborate anion [B3O3(OH)4]- with [B5O6(OH)4]-). The crystal structures of fifteen salts containing these polyborate anions are reported: [Co(en)3][B5O6(OH)4][B8O10(OH)6]∙5H2O (6), [Co(NH3)6]2[B4O5(OH)4]3∙11H2O (9), s-fac-[Co(dien)2][B7O9(OH)6]∙9H2O (11), [Co(diNOsar)]2[B3O3(OH)4]Cl5∙4.75H2O (12), [Cu(en)2][B5O6(OH)4]2∙2H2O (20), [Cu(pn)2{B5O6(OH)4}][B5O6(OH)4]∙4H2O (22), [Cu(TMEDA){B6O7(OH)6}]∙6H2O (23), [Cu(dac)2(H2O)2][Cu(dac)2][B7O9(OH)5]2∙4H2O (24), [Cu(N,N-dmen)2(H2O)][B5O6(OH)4]2·3H2O (27), [Cu(N,N-dmen){B6O7(OH)6}]·4H2O (28), [Ni(en){B6O7(OH)6}(H2O)2]∙H2O (37), [Ni(AEN)][B5O6(OH)4]∙H2O (38), [Ni(dac)2(H2O-)2][Ni(dac)2][B7O9(OH)5]2∙4H2O (39), [Ni(hn)2][B5O6(OH)4]2 (40), and s-fac-[Ni(dien)2][B5O6(OH)4]2 (41). All the synthesized compounds reported were characterized using spectroscopic (IR, multi-element NMR) and analytical (melting point, elemental analysis, magnetic susceptibility, thermal analysis, powder X-ray diffraction) techniques. The solid-state structures of transition metal complex polyborate salts all display multiple cation-anion H-bond interactions and these undoubtedly play a major role in the energetics of engineering these structures. For example, in compound [Co(NH3)6]2[B4O5(OH)4]3∙11H2O (9), fourteen of the 18 amino hydrogen atoms of the [Co(NH3)6]3+ cation are involved in secondary coordination to anions via H-bonds. Two unique polyborate anions, [B8O10(OH)6)]2- and [B7O9(OH)6]3- have been prepared and characterized in [Co(en)3][B5O6(OH)4][B8O10(OH)6]∙5H2O (6) and s-fac-[Co(dien)2][B7O9(OH)6]∙9H2O (11), respectively. vii The reaction of transition metal complex cations with boric acid in different ratios produced polyborate compounds with different polyborate anions e.g. reaction of [Cu(en)2]2+ with boric acid in 1:10 and 1:5 ratios produce polyborate compounds with pentaborate(1-) and tetraborate(2-) anions, respectively. New polyborate anion structural architectures are identified in this thesis: (i) the pentaborate(1-) anion in [Cu(pn)2{B5O6(OH)4}][B5O6(OH)4]∙4H2O (22) acts as a monodentate ligand coordinated to the Cu(II) cation, (ii) the hexaborate(2-) anion in [Cu(TMEDA){B6O7(OH)6}]∙6H2O (23) and [Cu(N,N-dmen){B6O7(OH)6}]·4H2O (28) coordinates as a tridentate ligand with the Cu(II) cations, and (iii) the hexaborate(2-) anion in [Ni(en){B6O7(OH)6}(H2O)2]∙H2O (37) coordinates as a bidentate ligand with the Ni(II) cation. This is the first time that such coordination mode (i) and (iii) have been observed.

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31

Omar, Ahmad. "Disentangling the Intrinsic Attributes and the Physical Properties in Cobalt-based Quaternary Heusler Compounds". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-199751.

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Abstract (sommario):

Heusler compounds are cubic intermetallics with a wide range of interesting properties, which are closely related to the structure of the material. In addition, several exotic physical phenomena have been predicted for different compositions in the family, but have not been experimentally realized. By and large, the lack of success in realization of various properties are due to the issues with intrinsic material attributes, which have been difficult to resolve as the relationship between them is not well understood. The aim of this work has been to unravel the entanglement between the intrinsic material attributes of cobalt-based quaternary Heusler compounds such as the structure, defects (disorder), chemical inhomogeneities etc., and the resulting physical properties.

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32

Vâlcu, Bogdan F. "Studies in perpendicular magnetic recording /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2004. http://wwwlib.umi.com/cr/ucsd/fullcit?p3127623.

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33

Guo, Ipin. "Hydroformylation of olefins by water soluble and asymmetric cobalt and platinum complexes". Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39855.

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Hydroformylation of olefins (OXO synthesis), one of the oldest organometallic catalytic reactions, continues to be of interest because of its commercial significance. Great interest recently has been placed on the development of immobilized homogeneous catalysts that combine the virtues of conventional heterogeneous and homogeneous catalysts. The objective of this dissertation is to investigate novel phosphine modified water soluble cobalt and platinum complexes as homogeneous and immobilized hydroformylation catalysts. The ligands include (1) Monodentate phosphines: P[ (CH₂ ) _n-C₆H₄-S0₃Na] ₃ (n = 0-3) and P[C₆H₄-NMe₃⁺BF₄⁻]₃; (2) Bidentate asymmetric phosphines: CHlRAPHOS(NMe₂)₄ (CHlRAPHOS = 2, 3-bis (diphenylphosphino) butane) , SKEWPHOS (NMe₂)₄ (SKEWPHOS = 2,4-bis(diphenylphospino)pentane), and DlOP(NMe₂)₄ (DlOP = 2,2-dimethyl-4,5-bis(diphenyl(phosphinomethyl)-1,3- dioxolane) ). These complexes were immobilized and/or recycled by four different methods: (1) Two phase catalysis; (2) Supported aqueous phase catalysis; (3) Catalyst supported on ion exchange resins; (4) Extraction of the catalyst from an organic phase into an aqueous phase. Catalytic results for the hydroformylation of a-olefins shows that nib (normal:branch of aldehyde product) ratio can be increased if proper alkyl-phosphine ligands are chosen. For example, as high as 18.5 of nib ratio was obtained in PtCl[P(C₆H₅)₃]₂-snCl₃ system and 5.6 in CO₂ (CO) ₆ [TRlMAPP] ₂ (TRlMAPP = trimethylamino-phenylphosphine) system. Metal leaching, from the aqueous phase to the organic phase during the catalytic reaction, was reduced by supporting the water soluble cobalt and platinum complexes onto a high surface area glass (CGP-350). For instance, 5.7% cobalt metal was found in the organic phase when CO₂(CO)₆(TPPTS)₂ was used under reaction conditions (TPPTS = triphenylphosphine trisulphonated salt). When the same cobalt complex was immobilized on glass, no cobalt metal leaching was observed. Asymmetric hydroformylation of styrene catalyzed by PtCl [SKEWPHOS (NMe₂) ₄] -SnCl₃ shows a very strong temperature dependence on optical selectivity. Enantiomeric excess (ee's) switches sign from S to R form at 57°C. At 25°C, there is 60.6% ee of S product, whereas 56.7% ee in favor of R product is observed at 100°C.
Ph. D.

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34

Cenzano-Fong, Bella S. "Synthesis and reactivity of a late metal metallacyclobutene complex and eta(4)-cyclopentadiene cobalt compounds /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1997. http://wwwlib.umi.com/cr/ucsd/fullcit?p9820851.

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35

N'Guessan, Gilbert Kouakou. "Réduction électrochimique du composé d'insertion graphite-chlorure de cobalt : étude du composé réduit graphite-cobalt". Grenoble INPG, 1989. http://www.theses.fr/1989INPG0082.

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Le compose d'insertion du graphite c#5cocl#2#,#1#0 est utilise en cathode d'une pile au lithium. La decharge d'une telle pile conduit a la reduction en deux etapes du chlorure de cobalt insere. Le compose ainsi reduit de formule chimique moyenne c#1#1co#0#,#6##0#,#8(co cl#2)#0#,#4##0#,#2(licl)#0#,#5 contient une phase dans laquelle le cobalt est insere en 1#e#r stade

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36

Lu, Yunxiang. "Study of electrochemical performance of strontium doped lanthanum cobalt oxides using electrochemical impedance spectroscopy and microelectrode array cell design /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/9818.

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37

Yi, Jae-Young. "Microstructure and magnetic properties of Co-(CoO, CoNiO2̳, NiO) and Cox̳Ni1̳-̳x̳-CoO nanocomposite thin films /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p3000403.

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38

Wang, Shengdong. "Transition metal-catalyzed reduction reactions adding value to bio-sourced compounds". Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S134.

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Le travail de recherche concerne l'utilisation de catalyseurs à base de métaux de transition: ruthénium, iridium, cobalt, argent, pour la transformation de substrats bio-sourcés renouvelables en produits à valeur ajoutée pour l'industrie chimique et l'énergie. La transformation par transfert d'hydrogène de l'acide lévulinique en γ-valérolactone a d'abord été développée avec de nouveaux catalyseurs du ruthénium et de l'iridium porteurs d'un ligand dipyridylamine et d'un chlorure en utilisant l'acide formique comme source d'hydrogène. Puis de nouveaux catalyseurs zwitterioniques de type ruthénium et iridium(sulfato)(dipyridylamine) ont été préparés et ils ont conduit aux meilleures productivités observées pour la réduction de l'acide lévulinique en γ-valérolactone par hydrogénation directe. Sur la base des excellentes performances des complexes iridium(sulfato)dans des processus de réduction, l'amination réductrice de l'acide lévulinique et de l'acide o-formylbenzoïque a été réalisée et a permis la synthèse efficace de dérivés de type pyrrolidones, en particulier à partir d'amines primaires encombrées. La déshydrogénation sélective de l'acide formique dans des conditions douces sans additif en milieu aqueux ou en absence de solvant a été développée avec les mêmes types de catalyseurs de l'iridium porteurs du ligand modifié diméthylaminodipyridylamine. Finalement, une méthode d'hydrogénation douce de cétones a été mise en évidence en présence d'un système catalytique à base de nanoparticules d'argent générées in situ. Ce système catalytique permet d'obtenir de bonnes efficacité et sélectivité vis-à-vis d'autre groupement fonctionnels
This research work deals with the use of catalysts based on transition metals, such as ruthenium, iridium, cobalt, silver for transformations of renewable bio-based substrates to valuable products for applications in chemical industry and energy. The transfer hydrogenation of levulinic acid to γ-valerolactone with novel ruthenium- and iridium(dipyridylamine)chloride complexes using formic acid as hydrogen source was first developed. Then, novel zwitterionic ruthenium and iridium(sulfato)(dipyridylamine) catalysts were prepared, which displayed the highest turnover numbers reported for the reduction of levulinic acid into γ valerolactone using H₂ as hydrogen source. Based on the high catalytic performance of the iridium(sulfato)complexes in reduction processes, the efficient reductive amination of levulinic acid and o formylbenzoic acid, in particular with bulky primary amines, for the synthesis of pyrrolidone derivatives was disclosed. The selective dehydrogenation of formic acid under mild conditions in aqueous media or neat conditions without using an organic additive has been developed using iridium catalysts of the same family equipped with a modified dimethylaminodipyridylamineas ligand. Finally, an unprecedented hydrogenation of ketones in the presence of in situ generated silvernanoparticleswas discovered. High efficacy and functional group selectivity have been achieved in most cases

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39

Rowan, Fraser S. "A study of the effects of oxygen environment on the stoichiometry, phase assemblage and stability of BiSCCO 2212 and 2201 using EPMA". Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369139.

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Abstract (sommario):

A method of performing accurate oxygen analysis on cuprate based superconducting materials was established using electron probe micro analysis (EPMA). A range of YBa₂Cu₃O_δ ceramics with varying oxygen concentration were used to test the method. Using YBCO as a reference material, a suitable standard for oxygen analysis of Bi₂Sr₂CaCu₂O_δ (BiSCCO-2212) materials was obtained. This standard was used to perform full elemental analysis of a range of BiSCCO-2212 crystals, post annealed in pO₂'s between 10^-5-2atm. When the average Cu valence of each crystal was calculated and plotted as a function of the critical temperature (T_c) for each crystal, it was shown that BiSCCO-2212 materials conformed to the 'universal' trend illustrated by most other HTS and did not exhibit anomalous behaviour as had been previously believed. The phase assemblage and superconducting properties of BiSCCO-2212 Ag-clad multifilamental wires, prepared using the powder-in-tube (PIT) method by BICC, were studied as a function of a time/temperature profile. pO₂ of the processing atmosphere was found to be the predominant factor in determining the stoichiometry of the 2212 phase within wires. The phase assemblage is not simply a function of pO₂ as previously believed and can be controlled, in part, by the post annealing temperature. Homogenisation of the phase assemblage in BiSCCO-2212 Ag-clad wires can be achieved by prolonged heating (96hrs) at an appropriate temperature. An investigation into the 10K superconducting BiSCCO phase has shown the Sr-rich solid solution to extend towards the ideal stoichiometry of 2:2:1 (Bi:Sr:Cu) with increasing pO₂. Using a combination of high pO₂ (60atm) to achieve the appropriate Bi:Sr stoichiometry followed by post annealing in N₂ to adjust the oxygen content, it was possible to prepare single-phase ceramics of stoichiometry Bi_2.11(2)Sr_1.90(2)Cu_0.99(2)O_δ with a T_c=10.5K(5).

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40

Kessler, Margalith. "Crystallographic studies of mono- to hexa-nuclear organometallic compounds of the chromium, iron and cobalt triads". Thesis, London Metropolitan University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321709.

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41

Hong, Pengda, e 洪鹏达. "Synthesis and characterization of LiNi0.6Mn0.35Co0.05O2 and Li2FeSiO4/C as electrodes for rechargeable lithium ion battery". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47150294.

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Abstract (sommario):

The rechargeable lithium ion batteries (LIB) are playing increasingly important roles in powering portal commercial electronic devices. They are also the potential power sources of electric mobile vehicles. The first kind of the cathode materials, LiXCoO2, was commercialized by Sony Company in 1980s, and it is still widely used today in LIB. However, the high cost of cobalt source, its environmental unfriendliness and the safety issue of LiXCoO2 have hindered its widespread usage today. Searching for alternative cathode materials with low cost of the precursors, being environmentally benign and more stable in usage has become a hot topic in LIB research and development. In the first part of this study, lithium nickel manganese cobalt oxide (LiNi0.6Mn0.35Co0.05O2) is studied as the electrode. The materials are synthesized at high temperatures by solid state reaction method. The effect of synthesis temperature on the electrochemical performance is investigated, where characterizations by, for example, X-ray diffraction (XRD) and scanning electron microscopy (SEM), for particle size distribution, specific surface area, and charge-discharge property, are done over samples prepared at different conditions for comparison. The electrochemical tests of the rechargeable Li ion batteries using LiNi0.6Mn0.35Co0.05 cathode prepared at optimum conditions are carried out in various voltage ranges, at different discharge rates and at high temperature. In another set of experiments, the material is adopted as anode with lithium foil as the cathode, and its capacitance is tested. In the second part of this study, the iron based cathode material is investigated. Lithium iron orthosilicate with carbon coating is synthesized at 700℃ by solid state reaction, which is assisted by high energy ball milling. Characterizations are done for discharge capacities of the samples with different carbon weight ratio coatings.
published_or_final_version
Physics
Master
Master of Philosophy

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42

Xu, Xiaoshan. "The magnetism of free cobalt clusters measured in molecular beams". Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14649.

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Magnetic properties of cobalt clusters (20 N 200) were studied in molecular beams. The magnetization of cobalt clusters is studied at a broad range of temperatures, magnetic fields and clusters sizes. It is shown that the agnetization of ferromagnetic clusters in a cluster beam can be understood as an adiabatic process using the avoided crossing theory. Besides the ground state that bears magnetic moment of about 2 Bohr magneton per atom, an excited state that has 1 Bohr magneton per atom was discovered for every cobalt cluster observed. The energy separations between the two states was investigated by photo-ionization experiments. The ionization threshold shows that the energy gap between the two states is on the order of 0.1 eV for small clusters (N 100) and vanishes for larger clusters. Experiments also show that the polarizability of the excited state is lower than that of the ground state, which indicates a significant electronic tructure difference between the two states. Two states are also found for iron clusters (20 N 200) for which the magnetic moments per atom are about 3 Bohr magneton for the ground state and 1 Bohr magneton for the excited states. This explains the fractional magnetic moments as well as the local magnetic order observed above the Curie temperatures for iron group ferromagnets. Further experiments show two states for manganese clusters for which the ground state has magnetic moment of 1 Bohr magneton per atom in about the same size range. This suggests that the two states are a universal phenomenon of 3d transition metal clusters, which originate from the interaction between 3d and 4s electrons.

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43

Crause, Chantelle. "Synthesis and application of carbene complexes with heteroaromatic substituents /". Access to E-Thesis, 2004. http://upetd.up.ac.za/thesis/available/etd-05252005-145146/.

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44

Kruger, John Scott. "Synthesis and characterization of several novel aluminum and gallium phosphates templated by cobalt complexes". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/30553.

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45

Straistari, Tatiana. "Synthesis and study of coordination compounds of cobalt, copper, palladium and nickel with polydentate ligands containing sulfur". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4352.

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Ce travail porte sur la synthèse, la caractérisation et l’évaluation en catalyse de réduction des protons en dihydrogène, de nouveaux complexes de Ni(II), Co(III), Cu(II) et Pd(II) basés sur des ligands de type thiosemicarbazone. La nature de l’espèce catalytique active a été étudiée par voltampérométrie cyclique et des propositions de mécanisme ont été formulés sur la base de calcul quantique de type DFT.Le premier chapitre introduit le contexte scientifique. Le second chapitre concerne la synthèse et la caractérisation des ligands de type N2S2 et des complexes mononucléaires associés de Ni, Cu et Pd. Le troisième chapitre présente la synthèse et la caractérisation de complexes binucléaires de Co et trinucléaire de Ni.Les études électrochimiques de ces complexes dans le DMF en présence d’une source de protons, nous a permis d’évaluer leur efficacité catalytique. Nos résultats montrent que les complexes du Cu et du Pd présentent une vague irréversible spécifique pour la réduction des protons, mais une décomposition est observée durant l’électrolyse. Par contre, les complexes de Ni et de Co ont montré une stabilité électrochimique ainsi que de bonnes performances catalytiques. En particulier, le nouveau complexe mononucléaire de Ni présente des propriétés catalytiques remarquables qui le classent parmi les meilleurs catalyseurs de la réduction des protons décrits dans la littérature. L’ensemble de ce travail fourni une description complète du comportement électrochimique des ligands de type N2S2 complexés à des métaux de transition. Il permet d’envisager des développements futurs dans l’amélioration des propriétés catalytiques de ces complexes
This work focuses on the synthesis, the characterization and the catalytic evaluation in the reduction of protons into dihydrogen, of new complexes of Ni(II), Co(III), Cu(II) and Pd(II) based ligands Type thiosemicarbazone. The catalytically active species during the process of the proton reduction was studied by cyclic voltammetry and mechanisms were formulated on the basis quantum chemical calculation.The first chapter introduces the scientific context, the goals and the main objectives of this work. The second chapter concerns the synthesis and the characterization of the N2S2 ligands and their associated mononuclear complexes, Ni, Cu and Pd. The third chapter presents the synthesis and the characterization of binuclear Co and trinuclear Ni based on N2S2 ligand.Electrochemical studies of these complexes in DMF in the presence of a proton source (trifluoroacetic acid), allowed us to evaluate their catalytic efficiency. Our results show that Cu and Pd complexes have a specific irreversible wave for the reduction of protons, but decomposition is observed during electrolysis, which makes these uninteresting complexes for the reduction of protons.On the contrary, Ni and Co complexes showed an electrochemical stability and good catalytic performances. In particular, the new mononuclear Ni complex exhibits remarkable catalytic properties that rank it among the best catalysts for the reduction of protons reported in the literature. All this work provided a complete description of the electrochemical behavior of N2S2 thiosemicarbazone ligands complexed to transition metals. It allows considering future developments in improving the catalytic properties of these complexes

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46

Kaspar, Tiffany C. "Materials and magnetic studies of cobalt-doped anatase titanium dioxide and perovskite strontium titanate as potential dilute magnetic semiconductors /". Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/9902.

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47

Orrock, Clive Martin. "The microstructure and properties of equiatomic iron-cobalt magnetic alloys with alloying additions". Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/38127.

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48

Hegarty, M. "The development of low temperature heat capacity results : a heat capacity study of some chlorammine cobalt(III) compounds". Thesis, University of Stirling, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306811.

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49

Ebke, Daniel [Verfasser]. "Cobalt-based Heusler compounds in magnetic tunnel junctions / Daniel Ebke. Fakultät für Physik - Abt. Experimentalphysik : Dünne Schichten und Nanostrukturen". Bielefeld : Universitätsbibliothek Bielefeld, Hochschulschriften, 2011. http://d-nb.info/1015182399/34.

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50

Spicer, M. D. "Higher oxidation state complexes of group Vb and VIb donor atom ligands : Compounds with cobalt(III) and copper(III)". Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382971.

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