Дисертації з теми "Zincate"
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1
Baillie, Sharon E. "Novel synthetic and structural advances in magnesiate and zincate chemistry." Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=18668.
Анотація:
Building on recent successes in mixed-metal chemistry, this research project aims to enhance the understanding of the complicated correlations existing between structural patterns and reactivities of alkali metal magnesiates and zincates together with exploring their applications in a number of fundamental organic transformation reactions such as metallation, alkyl addition and metal-halogen exchange reactions. Elucidating the effect that donor solvents can exert on the overall constitution of organometallic reagents, a series of novel solvated [(donor)MMgR3] and [(donor)2M2MgR4] (donor = THF, dioxane, TMEDA, PMDETA; M = Li, Na, K; R = CH2SiMe3) compounds have been prepared and fully characterised both in the solidstate and in solution using multinuclear NMR (including 1H-DOSY NMR) studies. A rich variety of structural motifs has been disclosed which range from simple monomers when polydentate ligands such as PMDETA are employed, such as [(PMDETA)LiMgR3] (6) and [(PMDETA )2MMgR4] (M = Na (9), K (11)), to much more complex polymeric structures using oxygen donor ligands dioxane or THF, such as [{(dioxane)2LiMgR3}8] (3), [{(dioxane)Li2Mg2R6}8] (4) and [{(THF)LiMgR3}8] (2). The first examples of unsolvated trisalkyl magnesiates [{NaMgR3}8] (12) and [{KMgR3}8] (16) have been unveiled which exhibit distinct 2D supramolecular structures in the solid-state constructed exclusively of electron deficient M-C bonds. The ability of novel potassium magnesiates to participate in direct magnesium-hydrogen exchange reactions was assessed with several aromatic and heteroaromatic substrates. In addition, key reaction intermediates have been structurally defined from metallation, alkyl addition and metal-halogen exchange reactions which provide compelling evidence that the outcome of these reactions are reliant on subtle changes in the coordination sphere of the bimetallic reagent employed. Thus, the reactivity of heteroleptic zincate [(T HF)LiZn(TMP)(tBu)2] (22) towards pyrazine has demonstrated that despite the presence of two nucleophilic tBu groups the selective two-fold deprotonation of the heterocycle pyrazine is preferred to form the unprecedented 2,5-di-zincated pyrazine molecule. These results are in contrast with those observed when pyrazine is confronted by the homoleptic alkyl zincate [(PMDETA)LiZn(tBu)3] (23) where the chemoselective addition of a tBu group to the (Sa(B-C of the heterocycle takes place under mild reaction conditions. Focussing on metal-halogen exchange reactions, the addition of LiOtBu has proved to greatly activate ZnEt2 towards zinc-iodine exchange reactions with 2-iodoanisole under mild conditions. Novel bimetallic approaches which allow the selective C4 functionalisation of unsaturated N-heterocyclic carbene IPr have been developed. Thus, the first direct zincation of an NHC was achieved by reacting sodium zincate [(TMEDA)Na(TMP)(tBu)Zn(tBu)] with IPr to form [(THF)3Na(IPr *)Zn(tBu)2] (41). 41 exhibits a unique chemical profile and can react efficiently with [ClAu(PPh3)] to form an unprecedented bis-gold [ClAu(IPr*)Au(PPh3)] (47) species. Extension of these reactivity studies to Na/Mg combinations allows the isolation of the first sodium magnesiate containing a deprotonated carbene molecule [(THF)3Na(IPr*)Mg(CH2SiMe3)2(THF)] (50).
2
Chohan, Zahid H. "Co-ordination chemistry of the 1,3-dithiole-2-thione (DMIT) and 2-one-4,5-dithiolato (DMIO) compounds." Thesis, University of Aberdeen, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244990.
Анотація:
Various bis-dmio and -dmit zincate complexes, [Q]2[Zn(dmio)2] [Q = NEt4, 1,4-dmp, Ph4P and FcCH2NMe3] and [Q]2[Zn(dmit)2] [Q = FcCH2NMe3], have been prepared and characterised by IR, 1H and 13C-NMR spectral and elemental analysis data. The solid state structure of [FcCH2NMe3]2[Zn(dmio)2] was determined by X-ray crystallography. The complexes, [Q]2[Zn(dmio)2] and [Q]2[Zn(dmit)2], have been further used as precursors of various dmio and dmit complexes of tin (IV) and antimony (III) and (V). Metal exchange reactions with these complexes have also been investigated. The neutral tin compounds, R2Sn(dmio) [RR' = Me2, Et2, Bu2, Ph2 and MeO2CH2CH2] have been synthesised and characterised by IR, 1H, 13C and 119Sn-NMR spectral and elemental analysis data and for Me2Sn(dmio) by X-ray diffraction. The compounds, [Q][R2Sn(dmio)X] [Q = NEt4, FcCH2NMe3 ; R = Ph, Et ; X = Cl] and [Q][R2(dmit)X] [Q = FcCH2NMe3 ; R = Ph ; X = Cl], have been prepared and halide (X) exchange reactions in [Q][R2Sn(dmio)X] [Q = NEt4 ; R=Ph ; X=Cl] have been investigated using alkali metal halides and pseudohalides [NaI, NaBr and NaSCN]. The solid state structures of [NEt4][Ph2Sn(dmio)Cl], [NEt4][Ph2Sn(dmio)-SCN] and [NEt4][NEt4][Et2Sn(dmio)Br] have been determined. The monoestertin bis-dmio complexes, [Q][MeO2CCH2CH2Sn(dmio)2] [Q = NEt4, 1,4-dmp and Ph4P] and the neutral diestertin dmio complex, [(MeO2CCH2CH2)2-Sn(dmio)], have been synthesised and characterised. The solid state structure of [NEt4][MeO2CCH2CH2Sn(dmio)2] has been determined. Also, the tris-dmio and dmit complexes, [Q]2[Sn(dmit)3] [Q = NEt4, 1,4-dmp, Ph4P and FcCH2NME3] and [Q][Sn(dmit)3] [Q = FcCH2NMe3] have been prepared and characterised. The antimony (III) bis-dmio complexes, [Q][SbIII(dmio)2] [Q = NEt4, 1,4-dmp, Ph4P and FcCH2NMe3], and antimony (III) bis-dmit complex, [Q][SbIII(dmio)2] [Q = FcCH2NMe3], have been synthesised and fully characterised by IR, 1H and 13C-NMR spectral and elemental analysis data.
3
Herd, Emma. "Alkali metal zincate chemistry : the importance of structure and stoichiometry on reactivity." Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24356.
Анотація:
Focusing on the area of cooperative bimetallic reagents, this report aims to advance our understanding on the construction and reactivity of alkali metal zincates. Extending previous studies on the synthesis of dialkyl(amido)zincates, unsolvated lithium zincate [LiZn(HMDS)Me₂] 4a was prepared by a cocomplexation approach, and its interaction with a range of Lewis basic solvents of varying denticity was examined. The effect of these donors on constitution and stability was assessed, resulting in the determination of a novel dialkyl(amido)zincate, [(PMDETA)LiZn(HMDS)Me₂] 5, containing an unusual terminal amido ligand. The influence of the amido group in these mixed-metal systems was also studied. Using the amide [NHDipp]⁻, a new family of lithium zincates has been synthesised, leading to the characterisation of the first dialkyl(amido)zincates based on a primary amide - [(PMDETA)LiZn(NHDipp)Me₂] 10 and [(THF)₃LiZn(NHDipp)(Me)₂] 11. X-ray crystallographic studies evidenced that, depending on the donor solvent employed, novel zincate formulations can be accomplished - as demonstrated by the isolation of the unprecedented zinc-rich zincate [LiZn₂(NHDipp)₂(Me)₃(THF)₃] 12, containing an unusual 2:1 zinc to lithium ratio. By synthesising the homoaryl lithium zincates [LiZnPh₃] 15 and [Li₂ZnPh₄] 16, and investigating their reactivity towards several electron-deficient N-heterocycles, a new transition metal free method enabling the efficient, regioselective arylation of acridine has been developed. Isolation of key reaction intermediates such as [(THF)₃Li(NC₁₃H₉-9-Ph)] 17, has provided important clues as to how these bimetallic systems operate. The reactivity of trimetallic mixtures based on [Zn(OPiv)₂·2LiCl] 27 and ArMgCl towards N-heterocyclic molecules was also investigated. Although unreactive towards arylation, new light has been shed on the constitution, reactivity and stability of these multi-component reagents. Finally, the bulky bis(amido)silyl ligand [Ph₂Si(NDipp)²⁻] has been successfully incorporated into two novel zincates, [{Na(THF)₆}+{(Ph₂Si(NDipp)₂)ZnEt}⁻] 29 and [(Ph₂Si(NDipp)₂)Zn(TMP)Na(THF)] 30, which have been employed in the regioselective zincation of benzothiazole and pyrrole, yielding the novel compounds [Na(THF)₂Zn(Btz)₃]₂ 31 and [Na₂(THF)₄Zn(NC₄H₄)₄]∞ 32.
4
Balloch, Liam. "Towards understanding synergic s-block chemistry : new insights from zincate and magnesiate reactions." Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=17205.
5
Robertson, Sherryl G. "The zincate immersion process for plating aluminium: A kinetic, electrochemical and morphological study." Thesis, Robertson, Sherryl, G. (1995) The zincate immersion process for plating aluminium: A kinetic, electrochemical and morphological study. PhD thesis, Murdoch University, 1995. https://researchrepository.murdoch.edu.au/id/eprint/52750/.
Анотація:
The zincate immersion process is used commercially to treat aluminium prior to electroplating. The aluminium is immersed into an alkaline zincate solution where the oxide layer is dissolved. An intermediate zinc coating is then formed on the surface through displacement. Despite having been used commercially for many decades, the process still experiences a number of problems. The reaction has been studied previously, but no one has yet taken advantage of the fact that the zincate immersion process is a cementation reaction, and a large body of knowledge exists on how to determine the mechanism of these types of reactions. This thesis presents such a study.
In the first part of this thesis, the results from a detailed investigation of the kinetics of the cementation of zinc by aluminium from an alkaline zincate solution are presented. The concentration of zincate ions was found to have a substantial effect on the nature of the reaction. At low zincate concentrations (0.01 M) the reaction was diffusion controlled, while at high concentrations (0.5 M) the reaction was chemically controlled. The rotation rate, sodium hydroxide concentration and temperature were also found to be of significance. The effect of changing the experimental parameters on the reaction could be interpreted using appropriate Evans’ diagrams (i.e. superimposed polarization diagrams for the reduction of zincate and the anodic oxidation of aluminium). Mixed potentials, recorded as a function of time under the various experimental conditions, provided complementary information. The morphology of the zinc deposits formed ranged from being spongy, non-adhesive and non-cohesive to being thin, flat, adhesive and cohesive. Again, the changes in morphology could be rationalized through the use of Evans’ diagrams.
The final part of this thesis presents a detailed study of one of the more common modifications to the zincate immersion process used industrially. This is the addition of ferric chloride, complexed with potassium sodium tartrate, to the zincate solution. The effect of this addition was investigated using the same techniques as above. It was concluded that the ferric chloride acts by oxidizing the edges of the zinc crystals, thereby inhibiting their formation and growth and resulting in the deposition of a more compact coating. Tartrate was found to have no purpose other than as a complexing agent for Fe(III). Alternative additives were explored.
6
ZIPPERIAN, DONALD CHARLES. "PHYSICAL AND CHEMICAL CHARACTERISTICS OF THE ZINCATE IMMERSION PROCESS FOR ALUMINUM AND ALUMINUM ALLOYS." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184123.
Анотація:
A detailed experimental study has been carried out to investigate the zincate immersion deposition process for 99.99%, 6061, and 356-T6 aluminum samples. In particular, the effect of iron and tartrate in the immersion bath, the aluminum surface preparation, and the relationship of the first immersion step to the second immersion step were investigated by chemical, electrochemical (polarization and rest potentials), and surface analytical scanning electron microscopy (SEM), transmission electron microscopy (TEM), Rutherford backscattering spectrometry (RBS), X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES) techniques. Eh-pH diagrams were constructed to determine the most stable zinc, iron, and aluminum species in solution. These diagrams predict that ferrous and ferric ions, as well as aluminum should form stable complexes with tartrate at the typical immersion deposition conditions (Eh -0.9 to -1.0 and pH 14 to 15). Experimentally, tartrate was found to enhance the dissolution rate of aluminum in highly caustic solutions. The addition of ferric chloride to the immersion bath produced coatings that were more crystalline, and also decreased the amount of hydrogen gas evolved in the second immersion step. The deposition of zinc and iron during the second immersion step was considerably less than that during the first immersion step. The second immersion coating became more adherent as the initial surface roughness decreased, and as grain size was increased the second immersion coating became thicker. For increasing grain size the micrographs for the first and second immersion coatings showed that the coatings became more localized. The second immersion coating thickness and morphology were also dependent upon several first immersion variables, such as bath temperature, immersion time and bath composition. Increased dissolution rates of aluminum in the first immersion produced thinner coatings with a finer crystallite growth. Increased bath temperature and increased first immersion time enhanced the dissolution rate of aluminum. The zinc coating slowed the dissolution rate of aluminum. When zinc was absent from the first immersion bath, the aluminum dissolution was much faster and resulted in thinner coatings upon subsequent second immersion. The molar ratio of zinc deposited to aluminum dissolved was a constant value of 1.1 for both first and second immersions; the molar ratio was also constant for the different aluminum substrates examined in this investigation.
7
Garden, Jennifer Anne. "Advances in synthetic, structural and reaction chemistry of zinc and zincate complexes containing alkyl and/or amido ligands." Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=23171.
8
Segale, Allan Davide. "Effetto del frenafiletti sul coefficiente d'attrito al serraggio in viti brunite." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Анотація:
Ad oggi, l'utilizzo dei collegamenti filettati nel campo delle costruzioni meccaniche è ancora piuttosto diffuso, favorito soprattutto dalla possibilità di avere a disposizione dei collegamenti particolarmente resistenti in condizioni operative e facilmente smontabili per operazioni di ispezione o manutenzione. Questa peculiare caratteristica, sfruttata in particolare anche in campo automobilistico, ha spinto nel corso degli anni la ricerca tecnico-scientifica ad indagare sempre meglio le proprietà di questi collegamenti, soprattutto per quanto riguarda le questioni legate all'attrito, di importanza fondamentale per la corretta messa in opera dei collegamenti filettati. Il presente studio ha lo scopo di coprire un'area grigia, non ancora del tutto esplorata, che tratta del comportamento tribologico di adesivi anaerobici (frenafiletti) applicati alle filettature, per operazioni di serraggio. In particolare, sulla base di procedure standard attualmente in uso presso i costruttori automobilistici, si è impostato un piano degli esperimenti per la valutazione degli effetti, in termini tribologici, delle variazioni di parametri legati alle operazioni di serraggio effettuate su collegamenti con viti brunite. I risultati, di particolare rilevanza ed utilità nel caso delle procedure industriali, mettono in evidenza alcuni comportamenti, talvolta inaspettati soprattutto per quanto riguarda l'effetto lubrificante reso dai frenafiletti.
9
Pierret, Alexandre. "Fonctionnalisation à distance par métallotropie de dérivés benzyliques." Electronic Thesis or Diss., Université de Lorraine, 2023. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2023_0032_PIERRET.pdf.
Анотація:
Cette thèse présente un développement de la réaction de fonctionnalisation à distance par réarrangement métallotropique sur des dérivés benzyliques. Le travail repose sur l’utilisation d’un unique réactif métallique, un triorganozincate de lithium, lequel permet la formation de deux liaisons C(sp3)-C(sp2) et C(sp3)-C(sp3) sur des sites distants de 5 atomes en une seule opération. Le premier chapitre se focalise sur les dérivés benzyliques iodés en position 4 du cycle aromatique. Des conditions réactionnelles inédites basées sur l’utilisation d’un solvant biosourcé sont proposées. Elles permettent d’atteindre une portée synthétique sans précédent pour une telle réaction à partir de ces substrats. L’influence du solvant est discutée. Le deuxième chapitre est consacré à l’étude mécanistique par DFT de chacune des étapes composant la séquence réactionnelle étudiée précédemment. Ainsi, l’échange halogène/métal, la migration-1,2 de ligand ou encore le réarrangement métallotropique sont investigués avec prise en compte minutieuse du solvant de prédilection de la réaction. Un apport expérimental vient compléter cette étude. Enfin, l’extension de cette transformation aux dérivés hétéroaromatiques benzyliques, en particulier les thiophènes, est l’objet de l’ultime chapitre de cette thèse. Les travaux rapportés définissent une approche de fonctionnalisation à distance où une même boîte à outils, composée d’une plateforme unique (thiophène halogéné porteur d’un phosphate benzylique) et d’un réactif organométallique de même nature (organozincate de lithium), offre plusieurs opportunités synthétiques selon les désirs de l’expérimentateurThis thesis presents a development of the remote functionalization reaction by metallotropic rearrangement on benzyl derivatives. The work is based on the use of a single metal reagent, a lithium triorganozincate, which allows the formation of two bonds C(sp3)-C(sp2) and C(sp3)-C(sp3) on sites 5 atoms apart in a single operation. The first chapter focuses on benzyl derivatives with an iodine in position 4 of the aromatic ring. Novel reaction conditions based on the use of a bio-based solvent are proposed. They allow to reach an unprecedented synthetic scope for such a reaction from these substrates. The influence of the solvent is also discussed. The second chapter is devoted to the mechanistic study by DFT of each step composing the reaction sequence studied previously. Thus, the halogen/metal exchange, the 1,2-migration of ligand or the metallotropic rearrangement are investigated with careful consideration of the solvent of the reaction. An experimental contribution completes this study. Finally, the extension of this transformation to benzylic heteroaromatic derivatives, in particular thiophenes, is the subject of the last chapter of this thesis. The reported work defines an approach of remote functionalization where a same toolbox, composed of a unique platform (halogenated thiophene bearing a benzyl phosphate) and an organometallic reagent of the same nature (lithium organozincate), offers several synthetic opportunities according to the experimenter's desires
10
Chaumont-Olive, Pauline. "Synthèse et développement de la réactivité des triorganozincates de lithium chiraux en addition nucléophile énantiosélective et application à la synthèse de produits bioactifs." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMR069/document.
Анотація:
Le développement de méthodes de synthèse asymétriques a largement été exploré au cours des vingt dernières années et en particulier par le biais de réactifs organométalliques. Bien que ces processus mènent à d’excellents résultats en terme d’énantiodiscrimination, l’objectif de cette thèse a été de développer de nouveaux outils de synthèse peu onéreux, respectueux des fonctions sensibles environantes et permettant l’accès aux composés attendus avec de bons rendements et excès énantiomériques. Dans cet optique, des triorganozincates de lithium chiraux ont été étudiés. Des méthodes d’alkylation et d’arylation 1,2 énantiosélectives d’aldéhydes, comportant comme partenaire chiral la (R)-N-(2-iso-butoxybenzyl)-1- phenyléthanamine, ont ainsi été développées et mises en application sur divers aldéhydes. Les alcools secondaires correspondants ont été obtenus avec de bons rendements (jusqu'à 83%) et d’excellents excès énantiomériques (jusqu'à 99%). Ces procédures ont ensuite été appliquées à la synthèse asymétrique de produits naturels et/ou bioactifs tels que la Spiromastilactone A, la (R)-Néobénodine et la (R)-Orphénadrine. Par ailleurs, la synthèse de nouveaux ligands de type amino-alcool a été développée dans le but ultime de désymétriser des substrats de type imines cycliquesThe development of new asymetric methodologies have been widely explored during the last twenty years and in particular through organometallic reagents. Although these processes lead to excellent results in terms of enantiodiscrimination, the goal of this thesis was to develop new tools: cheap, chemoselective and allowing the access to the desired compounds with high yields and enantiomeric excesses. In this context, chiral lithium triorganozincates have been studied. Enantioselective nucleophilic 1,2 alkylation and arylation of aldehydes reactions, including (R)-N-(2-iso-butoxybenzyl)-1-phenylethanamine as the chiral ligand, have been optimized toward various aldehydes. The expected secondary chiral alcohols have been obtained with good yields (up to 83%) and high enantiomeric excesses (up to 99%).These processes have been then applied to the asymmetric synthesis of naturals and/or bioactive compounds as Spiromastilactone A, (R)-Neobenodine and (R)-Orphenadrine. Finally, the access to new amino-alcohols have been developed with the ultimate goal to engage those species as the chiral partner when reacting chiral lithium zincates with imines
11
Rouen, Mathieu. "Les Zincates de lithium en addition nucléophile énantiosélective." Rouen, 2011. http://www.theses.fr/2011ROUES035.
Анотація:
Divers amidozincates ont été engagés dans des réactions d’additions nucléophiles sur des dérivés carbonylés. Des zincates tétracoordinés ont été étudiés dans un premier temps. Les paramètres de réaction ont d’abord été optimisés en série racémique (amidure = TMP, conversions complètes dans le THF à -78°C après 2h), puis l’utilisation d’un amidure chiral (dérivés de 3-aminopyrrolidines) a permis d’accéder à des alcools énantioenrichis à hauteur de 70% (rendement 60%). Une étude du processus stéréochimique de la réaction a été engagée par spectroscopie RMN. Cependant, du fait de phénomènes d’échanges entre les espèces, nous n’avons pas été en mesure de définir avec précision la nature des agrégats inducteurs. La suite de ce travail a considéré l’utilisation de zincates tricoordinés dans le même type de réaction. Les conditions réactionnelles ont comme précédemment été déterminées en version racémique puis transposées à une version énantiosélective. Pour cette dernière, dix nouvelles amines chirales comprenant un motif α-MBA ont été synthétisées. La présence d’un hétéroatome sur la chaîne latérale de l’amine, et en particulier un atome d’oxygène en δ de l’azote de l’amidure, conduit aux meilleurs résultats. L’encombrement de cette fonction éther joue également un rôle primordial dans la réaction test, et la présence d’un groupement iso-propoxy permet d’atteindre les niveaux d’inductions les plus élevés (jusqu'à 90% ee). Enfin, la nature de l’aldéhydes, ainsi que la partie nucléophile du zincate (R2Zn), ont été modulées et ont permis d’obtenir de bonnes à très bonnes énantiosélectivités (95% e. E. Pour R = Me)Various amidozincates were studied in enantioselective nucleophilic additions on carbonylated compounds. First, tetracoordinated zincates were considered. The optimization of the reaction was conducted on a racemic model (amide = TMP, complete conversion in THF at -78°C), then, the use of a chiral amide (derived from 3-aminopyrrolidine) gave access to enantioenriched alcohols with e. E. ’s up to 70% (60% yield). The stereochemical outcome of the reaction was examined thanks to the NMR technique. However, due to exchange phenomena between species, the exact structure of the inductive aggregate could not be determined. The use of tricoordinated zincates in the same kind of reaction was next undertaken. As previously, the optimal conditions of the reaction were determined on a racemic model to be transposed to an enantioselective version. For the latter, ten new chiral amines having an α-MBA pattern were synthesized. The presence of a heteroatom in the side chain of the amine, and in particular an oxygen atom in position δ from the nitrogen of the amide, led to the best results. The bulkiness of the ethereal function was found to play a crucial role, the presence of an iso-propoxy group affording the highest inductions (up to 90% ee). Finally, various aldehydes and zinc derivatives (R2Zn) were engaged and enantioselectivities up to 95% could be reached
12
Greco, Jeffrey Francis. "Preparation, reactivity, and structural studies of zincated C-nucleophiles." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3207757.
13
Hansson, Robert. "Phase equilibria of zincite containing systems relevant to zinc/lead smelting /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19174.pdf.
14
Ferrari, Jean Vicente. "Contaminação com sal de cloreto e cromatização da superfície do aço zincado no processo não-contínuo de zincagem por imersão a quente: influência no desempenho de tintas e determinação de pré-tratamentos para pintura adequados." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-05092006-124730/.
Анотація:
O processo industrial não-contínuo de zincagem por imersão a quente (ZIQ) pode ocasionar a contaminação superficial do aço-carbono zincado por imersão a quente (AZIQ) com resíduos de cloreto. Estes resíduos, se não forem efetivamente eliminados, podem influenciar negativamente no desempenho dos esquemas de pintura dos sistemas dúplex (zincagem mais pintura). Sabe-se que no processo de ZIQ, a cromatização é amplamente utilizada, entretanto, o efeito que este pós-tratamento exerce no desempenho dos esquemas de pintura ainda não é bem estabelecido. Neste contexto, este trabalho teve como objetivos: I - verificar o grau de contaminação no AZIQ com sal de cloreto devido ao próprio processo de ZIQ; II - verificar os efeitos da contaminação com sal de cloreto e da cromatização do processo ZIQ no desempenho de tintas aplicadas sobre o AZIQ; e III determinar pré-tratamentos para pintura adequados para o bom desempenho das tintas aplicadas sobre o AZIQ. A metodologia adotada para alcançar o objetivo I envolveu a zincagem de chapas de aço-carbono em diferentes prestadores de serviço de ZIQ, em diferentes condições. Estas chapas zincadas foram analisadas por microanálise química qualitativa por espectrometria de dispersão de energia (EDS) em microscópio eletrônico de varredura (MEV) e pela determinação dos teores de cloreto superficiais, por método de extração com água em ebulição. A partir dos resultados obtidos para se alcançar o objetivo I, foi possível definir as condições no processo de ZIQ que potencialmente causam maior contaminação da superfície do AZIQ com sal de cloreto. Assim, para se alcançar os objetivos II e III, chapas de aço-carbono foram zincadas naquelas condições de máxima contaminação com sal de cloreto e parte delas foi submetida ao pós-tratamento de cromatização. Em seguida, uma grande parte destas chapas zincadas (cromatizadas ou não) foi submetida aos pré-tratamentos para pintura de desengraxe com solvente orgânico, de hidrojateamento a alta pressão, de jateamento abrasivo ligeiro e de ação mecânica com esponja abrasiva e água quente. Finalmente, as chapas zincadas, incluindo as não submetidas aos pré-tratamentos, foram pintadas com uma demão de tinta de aderência mais uma demão de tinta de acabamento. As chapas zincadas e pintadas foram submetidas a ensaios acelerados (imersão em água destilada e exposição em câmara de umidade saturada) e não-acelerados de corrosão (exposição em estação de corrosão atmosférica) e avaliadas por meio dos ensaios tradicionais de acompanhamento de desempenho (grau de empolamento e ensaios de aderência de tinta) e eletroquímicos (medida de potencial de circuito aberto, curva de polarização e espectroscopia de impedância eletroquímica E.I.E.). Algumas chapas zincadas, antes da pintura, foram submetidas aos ensaios de caracterização física (exame microestrutural e morfológico em MEV e rugosidade superficial), química microanálise por EDS, difração de raios X e teor de cloreto superficial pelo método de extração com água em ebulição) e eletroquímica. Os resultados obtidos, neste estudo, permitiram verificar que a aplicação adicional de sal cloreto de amônio sólido durante o processo de ZIQ tende a aumentar o grau de contaminação superficial do AZIQ com cloreto e, as etapas de resfriamento e/ou de cromatização do processo também contribuem para esta contaminação. No geral, o desempenho do AZIQ cromatizado teve desempenho inferior em relação ao não-cromatizados. O hidrojateamento a alta pressão e a lavagem com água e ação mecânica foram os prétratamentos que proporcionaram os melhores desempenhos dos esquemas de pintura.The batch galvanizing process (BGP) can lead to surface contamination of hot-dip galvanized steel (HDGS) with chloride residues. If these residues are not effectively eliminated, they can influence negatively on the performance of duplex systems (galvanizing plus painting). It is known that the chromate quenching is widely used in the BGP, however the effect of this post-treatment on the performance of duplex systems is not well established yet. In this sense, this work aimed: I to verify the contamination degree of HDGS with chloride salt due to the BGP itself; II to verify the effects of the chloride salt contamination and chromate quenching on the performance of paints applied on HDGS; and III to determine the suitable surface preparation for painting in order for obtaining a good paint performance applied on HDGS. The adopted methodology to achieve goal I involved the galvanizing of steel plates in different service renderings with BGP, in different conditions. These HDGS plates were submitted to the qualitative energy dispersive microanalyses (EDS) in scanning electron microscopy (SEM) and to the determination of superficial chloride contents by the boiling water extraction method. From the obtained results, the conditions in the BGP that potentially lead to greater surface contamination of HDGS with chloride salt were determined. Thus, to achieve goals II and III, steel plates were galvanized under the maximum chloride salt contamination condition and part of them were submitted to chromate quenching. After that, a great part of these HDGS plates (chromated or non chromated quenching) was submitted to the surface preparations for painting through organic solvent cleaning, high pressure hydroblasting, sweep blasting and handled scrub cleaning with an abrasive sponge and hot distilled water. Finally, the HDGS plates, including those not submitted to the surface preparations for painting, were painted with one coat of primer plus one coat of finishing paint. The HDGS painted plates were submitted to accelerated (distilled water immersion and humidity chamber exposure) and non accelerated (atmospheric exposure) corrosion tests and their performance were verified by means of traditional tests (degree of blistering and paint adhesion) and electrochemical measurements (open circuit potential, polarization curve and electrochemical impedance spectroscopy E.I.S.). Before painting, some HDGS plates were submitted to tests for physical (microstructural and morphological analyses in MEV and surface roughness), chemical (EDS, X-ray diffraction and superficial chloride contents by the boiling water extraction method) and electrochemical characterization. The obtained results allowed verifying that the additional application of solid ammonium chloride salt during the BGP tends to increase the degree of superficial chloride contamination of the HDGS and, the water and/or chromate quenching also contribute for this contamination. In general, the chromated HDGS presented worst performances. The high pressure hydroblasting and the handled scrub cleaning with an abrasive sponge and hot distilled water were the surface preparations for painting that provided the best performances of paint systems.
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Pedroso, Danieli Cristina. "Análise de causas de rejeições de peças de aço zincadas a quente." Universidade Presbiteriana Mackenzie, 2009. http://tede.mackenzie.br/jspui/handle/tede/2745.
Анотація:
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Previous issue date: 2009-08-17In this work the causes of rejection of lots of artifacts from the company Produto para Linhas Preformados, PLP, were analyzed which are made of steel SAE 1010 and SAE 1020 and zinc coated by hot-dip galvanizing. Lots of samples from different manufacturers were selected, with different chemical composition and geometry, but belonging to rejected lots and approved lots in accordance with usual market standards. The rejections are due to problems related to the adhesion of the layer of zinc. The samples were submitted to optical microscopy test, scanning electron microscopy and X-ray diffractions for comparative checking of between the structures of zinc formed layers by hot -dip galvanizing. To verify the corrosion in coating failure, corrosion tests were performed in three different environments: urban environment considered to be low-polluted; environment simulating sea water, salt spray. There is no failure evidence between the zinc coating and the substrate structure; irregular coatings and not very well defined phases were found in the rejected parts. In regions with failures, the results show a behavior similar to the literature with the rapid formation of rust at the beginning of the exposure followed by a show oxidation.
Neste trabalho foram analisadas as causas da rejeição de lotes de artefatos da empresa Produto para Linhas Preformados, PLP, fabricados com aços SAE 1010 e SAE 1020 e zincados por imersão a quente. Foram selecionadas amostras de lotes de fabricantes diferentes, com composição química e geometrias distintas, pertencentes a lotes rejeitados e a lotes aprovados de acordo com normas usuais de mercado. As rejeições se devem a problemas relacionados a aderência da camada de zinco. As amostras foram submetidas a exames por microscopia óptica, microscopia de varredura e análises por difração de raio-X para verificação comparativa entre as estruturas das camadas de zinco formadas no processo zincagem por imersão a quente. Para verificar a corrosão nas falhas de revestimento de zinco, foram realizados ensaios de corrosão em três ambientes diferentes: ambiente considerado urbano de baixa poluição; ambiente simulando água do mar; câmara de névoa salina. Não há indício de relação entre a falha nos revestimentos de zinco e a estrutura do substrato; revestimentos irregulares e com fases não muito bem definidas foram encontrados nas peças rejeitadas. Nas regiões com falha, os resultados evidenciam um comportamento semelhante ao da literatura, com formação rápida de ferrugem no início da exposição das peças seguida por uma oxidação lenta.
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Korzenowski, Christa. "Tratamento de efluentes ácidos e alcalinos de zincagem eletrolítica por eletrodiálise." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1996. http://hdl.handle.net/10183/159031.
Анотація:
O presente trabalho propõe através do uso da eletrodiálise, um método de tratamento de efluentes de zincagem eletrolítica ácida e alcalina, sem a geração do lodo de hidróxidos metálicos, que são subprodutos do tratamento de efluentes convencional. Inicialmente foram estudados, separadamente, efluentes sintéticos contendo zinco e cloreto e os efluentes alcalinos contendo zinco, cianeto e hidróxido. Determinou-se nesses efluentes as melhores condições de uso da eletrodiálise, como melhor tempo, melhor densidade de corrente, melhor temperatura e melhor pH, observando-se fenômenos como polarização por concentração, corrente limite, influências do pH, da temperatura e da agitação. A partir dos resultados obtidos nesse estudo, utilizou-se a eletrodiálise para analisar a porcentagem de recuperação de cada íon usando-se dois tipos diferentes de membranas no mesmo sistema. Antes e depois de cada etapa do tratamento, determinou-se por análise química a concentração de poluentes nos efluentes. Obteve-se no final, um compartimento com água residual cujas concentrações de zinco e cianeto foram praticamente zero, e outros compartimentos contendo separadamente grandes quantidades de zinco, cianeto e hidróxidos que podem ser reutilizados na eletrodeposição de zinco.The present work proposes throught of use of electrodialysis a method of treatment of wastewater resulting from acidic and alkaline zinc electroplating without producing of rejectable metallic hydroxide trough convencional treatment o f effluents. lnitially zinc and cloride synthetic wastewaters and after cyanide and hydroxide syntetic wastewaters were separately studied. In this eflluents was determined the best conditions of use of electrodialysis, how the best time, the best current density, the best temperature, and the best pH, watching fenomene how concentration polarization, limiting current density, influences of pH, temperature and agitation. From the results obtained in these study, we use the electrodialysis to see a recuperation of each ion using two membranes diferents in the same sistem. The wastewater pollutants concentrations were chemically analysed, before and after each treatment estage lt was obtained, as final wastewater, a solution with zmc, cloride and cyanide concentrations practilly zero, and another solution contained separately big quantity of zinc, cloride, cyanide, and hydroxide all of witch may be reused in the electrodeposition of zinc.
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Rodrigues, Tania Regina Inacio. "Perda de carga provocada por engate rapido em tubulações de aço zincado." [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258406.
Анотація:
Orientador: Ana Ines Borri GenovezDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil
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Resumo: Amplamente utilizados em conjuntos portáteis de irrigação, os tubos de aço zincado com engate rápido proporcionam facilidade na operação e manuseio destes sistemas. Uma dificuldade frenquentemente encontrada pelos projetistas para o dimensionamento hidráulico dessas tubulações, refere-se a avaliação da perda de carga provocada pelo engate, por não dispor do valor do coeficiente de perda de carga. O presente estudo tem como objetivo determinar os coeficientes de perda de carga "K", para as condições dos tubos existentes no mercado nacional. Um estudo experimental foi conduzido no Laboratório de Hidráulica e Mecânica dos Fluidos da Faculdade de Engenharia Civil (FEC) da Universidade Estadual de Campinas, considerando tubos em aço zincado com engate rápido de diâmetros entre 0,050 a 0,150 m de três fabricantes diferentes. Como resultado desta pesquisa foram determinados valores dos coeficientes variando de 0,780 a 0,088 influenciados pelo diâmetro da tubulação e o fabricante, que serão portanto indicados para os projetistas deste sistema
Abstract: Widely used in portable irrigation pipelines, the steel galvanized pipes with quick couples make these systems of easier operation and maintenance. Often, project engineers find troubles for calculating these pipes. That is due to get the correct value of the couple head loss, as they do not have the coefficient to calculate it. The main objetive of this study was the determination of the head loss coefficients in the coupler considering Brazilian pipes. An experimental research was conducted in the Hidraulic and Fluids Mechanic Laboratory of CivilEngineering College at the University of Campinas, using quick couples steel galvanized pipes, with diameters ranging from 0,050 to 0,150m, and from three differents factories. As a result of this research, the had loss coefficients values were from 0,78 and 0,088, influenced by the diameter and the factory and these are proposed to be used in future projects
Mestrado
Recursos Hidricos
Mestre em Engenharia Civil
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Denichoux, Aurélien. "Réarrangements d'époxydes acétyléniques : applications synthétiques." Paris 6, 2006. http://www.theses.fr/2006PA066464.
Анотація:
L’étude de trois réarrangements d’époxydes acétyléniques est reportée dans ce manuscrit. Le premier réarrangement effectué via un zincate acétylénique peut être apparenté à une SNi. L’instabilité configurationnelle de l’allénylalkylzinc intermédiaire a notamment été démontrée. Cette réaction permet la synthèse de divers alcools alléniques et homopropargyliques ainsi que de diols-1,3. Le deuxième réarrangement s’effectue par addition de titane(II) ou zirconium(II) sur la triple liaison de l’époxyde acétylénique. Il s’ensuit alors une ouverture de celui-ci puis une élimination pour conduire aux énynes. Dans le dernier réarrangement, deux équivalents de bases lithiés sont ajoutés sur l’époxyde acétylénique. Après la déprotonation en position acétylénique, une deuxième déprotonation a lieu en position propargylique. Une ouverture de l’époxyde par migration-1,2 d’hydrure conduit alors à un intermédiaire dilithié qui fournit après hydrolyse les cétones -alléniques.
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Bernardes, Andrea Moura. "Processo simplificado de tratamento de efluentes líquidos de zincagem eletrolítica contendo soluções de cianeto." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1989. http://hdl.handle.net/10183/130129.
Анотація:
O presente trabalho propoe um método de tratamento dos efluentes de zincagern eletrolítica alcalina de peças de aço e/ou ferro fundido sem segregação dos diferentes tipos de águas residuais. Inicialmente foram estudados, separadamente, efluentes sintéticos contendo cromo hexavalente e efluentes sintéticos contendo cianeto. Determinou-se nessas aguas residuais a relação entre potencial redox e pH, potencial redox e concentração de poluentes, potencial redox e volume adicionado de agente redutor e/ou oxidante e estudou-se a cinética de reaçao entre Cr +6 e agente redutor (Na - 2s 2o4 + Feso4), e CN e agente oxidante (NaOCl). Estabeleceu-se, então, o melhor processo de tratamento para cada um desses efluentes. A partir dos resultados obtidos nesses estudos, determinou- se o melhor tratamento para a mistura dos efluentes do processo. Nesse caso considerou-se a oxidação de cianeto com NaOCl, a redução de cromo hexavalente em meio alcalino com Na 2s 2o4 e Feso4 e a precipitação de metais utilizando Separan AP 273 Prerniurn corno agente floculante corno as etapas a serem seguidas. Antes e apos cada etapa do tratamento, determinou-se por análise química a concentração de poluentes no efluente. Obteve-se, corno efluente final, urna água residual com concentrações de ferro, zinco, cianeto e cromo abaixo dos limites de lançamento de poluentes determinados pela Secretaria Especial do Meio Ambiente (SEMA).The present work proposes a treatment of wastewater resulting from alkaline zinc electroplating of steel and/or cast iron pieces without segregation of the different wastewaters types. Initially cyanide synthetic wastewaters and hexavalent chromium synthetic wastewaters were separately studied. The relationship between ORP and pH, ORP and pollutants concentration, ORP and reducing and/or oxidizing agent added volume was determined, and the reaction kinetics between Cr +6 and reand CN and oxidizing agent (NaOCl) was studied. The best treatment process for each one of these wastewaters was established. From the results obtained in these studies, the best treatment for the process wastewaters mixture was determined. ln this case the sequence of steps followed were cyanide oxidation with NaOCl, hexavalent chromium reduction at alkaline pH with Na 2s 2o4 and Feso4 and metals precipitation with SEPARAN AP 273 Prernium as flocculation agent. Before and after each treatment stage, the wastewater pollutants concentrations were chemically analysed. It was obtained, as final wastewater, a treated solution with iron, zinc, cyanide and chromium concentrations below the pollutants discharge limits determined by Secretaria Especial do Meio Ambiente (SEMA).
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Bittencourt, Sérgio Deitos. "Tratamento de efluentes de zincagem eletrolítica ácida por eletrodiálise : utilização de densidades de corrente inferiores e superiores a limite." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/180147.
Анотація:
A galvanoplastia está entre os processos industriais que mais descartam contaminantes no meio ambiente. Os efluentes gerados contêm elevada carga de metais e sais que necessitam ser tratados, para a recuperação da água e a concentração dos produtos químicos, possibilitando suas reutilizações no processo. Novas tecnologias para o tratamento de efluentes contaminados com metais estão sendo pesquisadas e a eletrodiálise (ED) tem se mostrado eficiente para a recuperação da água e a concentração de eletrólitos. Neste método eletroquímico de separação por membranas, as espécies iônicas em solução são transportadas através de membranas íon-seletivas pela aplicação de um campo elétrico, o que possibilita a separação de cátions e ânions, com a vantagem de remover os metais contaminantes e, simultaneamente, recuperar a água. Um parâmetro importante a ser avaliado é o transporte dos íons através das membranas, o qual foi analisado no presente trabalho por meio da utilização da técnica de caracterização eletroquímica denominada cronopotenciometria, onde um pulso de corrente é aplicado entre dois eletrodos dispostos nas extremidades de uma célula eletroquímica e a queda do potencial através da membrana é medida.O foco deste estudo foi a aplicação de correntes abaixo e acima da corrente limite, obtidas por meio das curvas corrente-potencial (CVC), com a utilização de sistemas em bancada e piloto, para o tratamento de águas de lavagem dos processos de zincagem eletrolítica ácida e soluções sintéticas com e sem a presença de aditivos. Foram empregadas membranas comerciais fornecidas pela Hidrodex® (catiônica - HDX 100 e aniônica - HDX 200). Os resultados obtidos mostraram que a ED mostrou-se eficaz para a remoção dos íons metálicos e para a recuperação da água, removendo no mínimo 98% dos contaminantes nos ensaios realizados com diferentes densidades de corrente.The metalfinishing process is one of the industrial processes with the highest disposal of contaminants in the environment. The produced waste contains a high level of metals and salts and requires treatment, in order to reuse chemicals and water in the process. New technologies for the treatment of waste contaminated by metals are being researched and the electrodialysis (ED) has been found effective to water recovery and electrolyte concentration. In this electrochemical membrane separation process, the ionic species in solution are transported through ion-exchange membranes by applying an electric field, which allows the separation of cations and anions. This process has the advantage of removing metals, recovering, at the same time, water. One important parameter to be assessed is the transport through the membranes, which has been analyzed in this study by using the electrochemical characterization technique called chronopotentiometry. In this process, a current pulse is applied between two electrodes positioned on the extremities of an electrochemical cell and the potential drop through the membrane is measured. The study focus was the use of currents below and above the limit current, which were obtained through the current-potential curves (CVC). Bench and pilot systems were used for the treatment of the washing waters used in the processes of acid zinc electroplating and synthetic solutions with and without the presence of additives. Commercial membranes provided by Hidrodex™ (cation membrane - HDX 100 and anion membrane - HDX 200) were used. The results have shown that the electrodialysis is efficient for the removal of metallic ions and for the recovery of water. The trials performed with different current densities showed that the electrodialysis removed at least 98% of the contaminants.
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Costa, Josiane Soares. "Avaliação do revestimento de conversão à base de zircônio e tanino sobre aço zincado por eletrodeposição." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/96644.
Анотація:
O pré-tratamento de superfícies metálicas é utilizado para aumentar o desempenho contra a corrosão. Muitas peças, de diversos tamanhos, são cromatizadas, resultando em uma grande quantidade de efluentes e resíduos sólidos gerados desde o desengraxe inicial até a lavagem final. O cromo hexavalente é tóxico e cancerígeno. Isso vai contra a grande preocupação mundial da atualidade: sustentabilidade e redução do impacto ambiental. Novos processos sustentáveis têm sido estudados para reduzir os impactos ambientais. Portanto, este trabalho apresenta o desempenho de revestimentos nanocerâmicos à base de zircônio sobre substratos de zinco obtidos por eletrodeposição em meio ácido e meio alcalino. Um revestimento de nanocerâmico e posterior aplicação de revestimento tanino como potencial corante amarelo, foi avaliado, em relação aos revestimentos de cromato (CrIII e CrVI). O revestimento “nano Zr” é obtido através de solução de conversão à base de ácido hexafluorzircônio, formando camadas nanoestruturadas de óxido de zircônio na superfície. A utilização do revestimento à base de Zr melhora a resistência à corrosão do aço zincado. A adição de um tanino possibilita a visualização do revestimento “nano Zr” sobre as peças zincadas, visto que sua camada é, originalmente, transparente. Os ensaios de EIE e polarização demonstraram um desempenho equivalente do revestimento “nano Zr” com posterior aplicação de revestimento tanino ao revestimento de CrIII para as peças zincadas alcalina e ácida. Foi conseguida a cor amarela esperada para estas amostras, com a aplicação dos revestimentos em duas etapas. Os resultados demonstraram que o uso deste tipo de revestimento é promissor na substituição do processo de cromatização.Pre-treatment of metal surfaces is used to increase the performance against corrosion. Many pieces of different sizes are chromatid, resulting in a large amount of wastewater and solid waste generated from the initial to the final stages of the process. Hexavalent chromium is toxic and carcinogenic. This goes against the great global concern today: sustainability and reducing environmental impact. New sustainable processes have been studied to reduce environmental impacts. Therefore, this paper presents the performance of zirconium nanoceramic based coatings on zinc substrates obtained by electrodeposition in acidic and alkaline baths. A nanoceramic coating and subsequent application of a potential tannin yellow dye was evaluated in relation to the chromate coatings (CrIII and CrVI). The coating "nano Zr" is obtained through conversion based solution hexafluorzirconic acid forming nanostructured layers of zirconium oxide on the surface. The use of Zr based coating improves the corrosion resistance of galvanized steel. The addition of a tannin allows visualization of the coating "nano Zr" on galvanized parts, because its layer is originally transparent. The EIS and polarization tests showed an equivalent coating performance "nano Zr" with further application of the coating tannin CrIII for alkaline and acidic parts galvanized coating. In addition, it was achieved the expected yellow for these samples, with the application of the coatings in two steps. The results showed that the use of this type of coating is promising in the replacement of chromating process.
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Zhao, Peng. "The Attempted Synthesis of Carba-Nicotinic Acid Mononucleotide Methyl Ester using the Zincke Reaction." University of Toledo Health Science Campus / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=mco1488576282701401.
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Daltro, Adnauer Tarquínio. "Soldagem a arco elétrico com proteção gasosa em juntas de chapas finas de aço." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-16092016-160549/.
Анотація:
O uso de chapas finas de aço, revestidas ou não, tem sido crescente nos últimos anos, principalmente aquelas que tem revestimento à base de zinco. Isto ocorre tanto na indústria automobilística e mecânica como na construção civil, que geralmente fabricam suas peças e estruturas utilizando um procedimento de soldagem. O objetivo deste trabalho é estabelecer procedimentos de soldagem à arco elétrico com proteção gasosa - GMAW - com transferência por curto circuito, para elementos de chapa fina de aço carbono não revestido e aço zincado, de modo a se obter junções de qualidade aceitável e diminuição das distorções decorrentes dos ciclos térmicos presentes durante a soldagem e, consequentemente a redução das tensões residuais. Em termos de qualidade da solda, propões-se uma combinação de consumíveis disponíveis no mercado, de modo a reduzir os defeitos como: porosidade, respingos, trincas e perda de revestimento. No caso das chapas finas de aço zincado, a melhor combinação de consumíveis encontrada foi: arame com baixo teor de desoxidantes, ER70S-3, e como gás de proteção a mistura 8% CO2 + 92% Ar. Quanto à redução e controle das distorções, três técnicas são utilizadas. A técnica que utiliza em escoadouro dinâmico de calor, formado por um jato de gás refrigerador aplicado logo após o arco de solda durante a soldagem, apresentou maior eficiência na redução das distorções, provenientes do ciclo térmico.The thin sheet steels, coated or not, has been widely used nowadays, mainly the hot dip galvanized steel sheets. It\'s observed as in the mechanic and automobilist industry as in the civil construction that in manufacturing of pieces and structures employ welding procedures. The aim of this work is to establish procedures to gas metal are welding with short circuit transfer of thin sheet steel elements, not coated and zinc-coated steel, in order to get junctions of acceptance quality and reduction of welding stress and distortion. This distortion arise of the thermal cycles that occur during the welding. In terms of the weld quality is defined the best consumables combination available in the market, in such a way to reduce the weld defects like porosities, spatters, cracks and loss of covering. To galvanized steel sheets, the combination: wire ER70S-3 and mixture 8%CO2 + 92% Ar showed the best performance. Three techniques were employed for control and reduce the welding distortion. One that using a spot heat sink following the arc, in this case the cooling jet, was more efficient that others techniques.
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Viana, Gustavo Henrique Ribeiro. "Estudos para a síntese da viscosamina, de análogos oxigenados e de novos sais de piridínio quirais usando a reação de zincke." Universidade Federal de Minas Gerais, 2008. http://hdl.handle.net/1843/SFSA-867UVE.
Анотація:
This work was divided into two parts. The first part deals with the attempt at the synthesis of the marine alkaloid viscosamine, a macrocycle of natural occurrence, and its oxygenated analogues. The second part deals with the synthesis of chiral pyridinium salts. The Zincke's reaction was chosen to perform the key step that would lead to viscosamine and its oxygenated analogues; and for the introduction of the stereocenter directly linked to the ring nitrogen of chiral pyridinium salts. The studies to obtain viscosamine did not lead to total synthesis of this alkaloid. In addition to the several difficulties encountered during the attempts to obtain this compound, its synthesis was described for the first time by another group during our research work. So it was decided to interrupt the viscosamine synthesis, and start the synthesis of new oxygenated analogues of this alkaloid. In this work a new oxygenated macrocycle was obtained in low yield. During our attempts of the synthesis of viscosamine analogues we obtained a new oxygenated analogue of marine alkaloid teonalidine C. For the synthesis of chiral pyridinium salts, new compounds with different chain alkyl groups attached to position 3 of the pyridine ring were obtained. It was also shown that is possible to use microwaves for the synthesis of Zincke's salts in the absence of any solvent, and for the synthesis of several chiral pyridinum salts using 1-butanol or water as a solvent of the reaction. The use of microwaves irradiation to prepare compounds in the absence of solvent or the synthesis of molecules in water as described above, is very important regarding the development of safer and ecologically correct methodologies. Finally, for the first time the antimicrobial activity of Zincke's salts was quantified. Of the eleven salts tested at least nine of them showed activity against one of the bacteria tested.Este trabalho foi dividido em duas partes. A primeira parte trata da tentativa de síntese do alcalóide marinho viscosamina, um macrociclo de ocorrência natural, e de análogos oxigenados. A segunda parte trata da obtenção de sais de piridínio quirais inéditos. A reação de Zincke foi a alternativa escolhida para a realização da etapa chave que levaria à síntese da viscosamina e de seus análogos oxigenados bem como para a introdução do estereocentro diretamente ligado ao nitrogênio nos sais de piridínio quirais. Os estudos para a obtenção da viscosamina não levaram à síntese total deste alcalóide. Além das diversas dificuldades enfrentadas durante a tentativa para sua obtenção, sua síntese foi descrita pela primeira vez por outro grupo de pesquisa no decorrer do trabalho. Portanto, optou-se por realizar a síntese de análogos oxigenados inéditos desse composto. Destes estudos, Um macrociclo inédito oxigenado foi obtido com baixo rendimento. Durante as tentativas de síntese de análogos da viscosamina obteve-se um composto oxigenado inédito análogo ao alcalóide marinho teonalidina C. Quanto à síntese dos sais de piridínio quirais, foi possível obter compostos inéditos com diferentes grupos alquila de cadeia longa ligados à posição 3 do anel piridínico. Conseguiu-se também demonstrar a viabilidade do uso de microondas tanto para a síntese de sais de Zincke na ausência de solvente quanto para a síntese de diversos sais de piridínio quirais já conhecidos usando 1-butanol ou água como solvente da reação. O uso da irradiação de microondas para a obtenção de compostos na ausência de solvente ou em meio aquoso representa um importante avanço no que se refere ao desenvolvimento de metodologias mais seguras, ecologicamente corretas e que consomem menos energia quando comparados aos métodos tradicionais de síntese. Finalmente, foi avaliada pela primeira vez a atividade antimicrobiana de sais de Zincke. Dos onze sais testados pelo menos nove deles apresentaram alguma atividade contra uma das bactérias testadas.
25
Berville, Mathilde. "Radicaux π-conjugués pour la construction et le contrôle redox d'assemblages moléculaires". Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF050/document.
Анотація:
La conduction dans les matériaux organiques est un défi fondamental relevé par de nombreux chercheurs pour adapter au mieux la structure des matériaux à leur application. Les radicaux pi-conjugués sont les plus petites entités pouvant être le support d’une charge délocalisée. Ce travail s’inscrit dans le domaine de la synthèse de composés électro-actifs conduisant à des radicaux pi-conjugués pour l’auto-assemblage et le contrôle redox des propriétés de matériaux. Le chapitre 1 introduit les interactions spécifiques aux radicaux pi-conjugués et les propriétés physicochimiques liées aux édifices construits sur ces interactions. L’utilisation de ces interactions est ensuite illustrée par différents exemples choisis de la littérature. Le chapitre 2 porte sur la synthèse de dérivés de viologènes et la formation d’auto-assemblage en solution. Le chapitre 3 concerne le développement de synthèses de bis-viologènes cycliques suivi de l’étude de leur structure à l’état cristallin et en solutionConduction in organic materials is a current challenge addressed by many research groups in order to adapt the structure of materials to their expected applications. The understanding of the conduction requires the exploring of conjugated pi-radicals which are the smallest vector for charge delocalisation. This work focuses on the synthesis of electro-active materials, precursors of conjugated pi-radicals for the self-assembly and the redox control of the physical properties of materials. The first chapter introduces intermolecular interactions that are specific of conjugated pi-radicals and the relevant physical evidences characterizing the interactions. The use of these interactions is then illustrated by selected literature examples. The second chapter describes the synthesis of viologens and the formation of assembly in solution. The third chapter deals with the development of synthesis of bis-viologen cyclophanes and their studying both in the solid state and in solution
26
Zincke, Fabian [Verfasser], Ulrike [Gutachter] Stein, Edda [Gutachter] Klipp, and Stephan Michael [Gutachter] Feller. "Biomarker based therapies in high risk cancer patients - MACC1 as molecular target / Fabian Zincke ; Gutachter: Ulrike Stein, Edda Klipp, Stephan Michael Feller." Berlin : Humboldt-Universität zu Berlin, 2020. http://d-nb.info/1202775608/34.
27
Carpinelli, Nicolo. "Definizione di una metodica per il controllo in continuo delle proprietà meccaniche su prodotti di acciaio laminati e zincati mediante sensore di rilevamento della magnetizzazione residua e sviluppo del ciclo produttivo di un materiale bifasico." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6936/.
Анотація:
Questo elaborato presenta un metodo per lo sviluppo di correlazioni lineari con lo scopo di determinare le proprietà meccaniche di un acciaio laminato e zincato utilizzando un sensore che percepisce la magnetizzazione residua del materiale. Vengono utilizzati metodi statistici di analisi della varianza per lo studio delle funzioni di regressione lineari. Lo studio effettuato è stato sviluppato per la lavorazione di zincatura di coils presso Marcegaglia spa, stabilimento di Ravenna. È risultato evidente che la sola misurazione della magnetizzazione residua non fosse sufficiente per la determinazione delle proprietà meccaniche, a tale proposito sono stati sviluppati dei modelli di calcolo con funzioni multivariabili e, attraverso risolutori che minimizzano la differenza quadratica dell'errore, si sono determinati i coefficienti di regressione. Una delle principali problematiche riscontrate per la definizione delle correlazioni è stato il reperimento dei dati necessari per considerare affidabili i risultati ottenuti. Si sono infatti analizzate solamente le famiglie di materiale più numerose. Sono stati sviluppati tre modelli di calcolo differenti per parametri di processo di produzione utilizzati per la definizione delle correlazioni. Sono stati confrontati gli errori percentuali medi commessi dalle funzioni, gli indici di regressione che indicano la qualità della correlazione e i valori di significatività di ogni singolo coefficiente di regressione delle variabili. Si è dimostrato che la magnetizzazione residua influisce notevolmente, così come i parametri dei processo di ricottura del materiale, come le temperature in forno, lo spessore e le velocità. Questo modello di calcolo è stato utilizzato direttamente in linea per lo sviluppo di un ciclo ottimale per la produzione di un nuovo materiale bifasico. Utilizzando il modello per la predizione delle proprietà meccaniche si è concluso che per limiti impiantistici la chimica del materiale utilizzata non fosse idonea. Si è perciò utilizzato un acciaio con percentuali di carbonio, manganese e cromo differenti. In conclusione del progetto si sono formulate delle possibili alternative di funzioni di regressione che utilizzano il valore della durezza piuttosto che il valore di magnetizzazione residua. Si è appurato che l'utilizzo di un durometro, anziché il sensore studiato, potrebbe risultare una valida alternativa al sensore studiato.
28
Pokhrel, Lok R., and Phillip R. Scheuerman. "Ecological Risk Assessment of Zinc Oxide Nanoparticles." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/2962.
29
Johansen, Jonathan Frederick. "Mathematical modelling of primary alkaline batteries." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16412/1/Jonathan_Johansen_Thesis.pdf.
Анотація:
Three mathematical models, two of primary alkaline battery cathode discharge, and one of primary alkaline battery discharge, are developed, presented, solved and investigated in this thesis. The primary aim of this work is to improve our understanding of the complex, interrelated and nonlinear processes that occur within primary alkaline batteries during discharge.
We use perturbation techniques and Laplace transforms to analyse and simplify an existing model of primary alkaline battery cathode under galvanostatic discharge. The process highlights key phenomena, and removes those phenomena that have very little effect on discharge from the model. We find that electrolyte variation within Electrolytic Manganese Dioxide (EMD) particles is negligible, but proton diffusion within EMD crystals is important. The simplification process results in a significant reduction in the number of model equations, and greatly decreases the computational overhead of the numerical simulation software. In addition, the model results based on this simplified framework compare well with available experimental data.
The second model of the primary alkaline battery cathode discharge simulates step potential electrochemical spectroscopy discharges, and is used to improve our understanding of the multi-reaction nature of the reduction of EMD. We find that a single-reaction framework is able to simulate multi-reaction behaviour through the use of a nonlinear ion-ion interaction term.
The third model simulates the full primary alkaline battery system, and accounts for the precipitation of zinc oxide within the separator (and other regions), and subsequent internal short circuit through this phase. It was found that an internal short circuit is created at the beginning of discharge, and this self-discharge may be exacerbated by discharging the cell intermittently. We find that using a thicker separator paper is a very effective way of minimising self-discharge behaviour.
The equations describing the three models are solved numerically in MATLABR, using three pieces of numerical simulation software. They provide a flexible and powerful set of primary alkaline battery discharge prediction tools, that leverage the simplified model framework, allowing them to be easily run on a desktop PC.
30
Johansen, Jonathan Frederick. "Mathematical modelling of primary alkaline batteries." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16412/.
Анотація:
Three mathematical models, two of primary alkaline battery cathode discharge, and one of primary alkaline battery discharge, are developed, presented, solved and investigated in this thesis. The primary aim of this work is to improve our understanding of the complex, interrelated and nonlinear processes that occur within primary alkaline batteries during discharge. We use perturbation techniques and Laplace transforms to analyse and simplify an existing model of primary alkaline battery cathode under galvanostatic discharge. The process highlights key phenomena, and removes those phenomena that have very little effect on discharge from the model. We find that electrolyte variation within Electrolytic Manganese Dioxide (EMD) particles is negligible, but proton diffusion within EMD crystals is important. The simplification process results in a significant reduction in the number of model equations, and greatly decreases the computational overhead of the numerical simulation software. In addition, the model results based on this simplified framework compare well with available experimental data. The second model of the primary alkaline battery cathode discharge simulates step potential electrochemical spectroscopy discharges, and is used to improve our understanding of the multi-reaction nature of the reduction of EMD. We find that a single-reaction framework is able to simulate multi-reaction behaviour through the use of a nonlinear ion-ion interaction term. The third model simulates the full primary alkaline battery system, and accounts for the precipitation of zinc oxide within the separator (and other regions), and subsequent internal short circuit through this phase. It was found that an internal short circuit is created at the beginning of discharge, and this self-discharge may be exacerbated by discharging the cell intermittently. We find that using a thicker separator paper is a very effective way of minimising self-discharge behaviour. The equations describing the three models are solved numerically in MATLABR, using three pieces of numerical simulation software. They provide a flexible and powerful set of primary alkaline battery discharge prediction tools, that leverage the simplified model framework, allowing them to be easily run on a desktop PC.
31
Lam, Jonathan K. "Part I| Ring-Rearrangement Metathesis of Himbert Arene-Allene Cycloadducts for the Rapid, Modular Construction of Complex Molecular Scaffolds. Part II| Application of Zincke Aldehydes Toward the Synthesis of Gelsemine." Thesis, University of California, Irvine, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3646740.
Анотація:
Developing new synthetic methods and strategies is an important area of research in organic chemistry. Especially useful are transformations that rapidly and rationally generate complex molecular architectures, with multiple new bonds and new stereocenters, from simple, achiral and modular precursors. This dissertation discusses the synthetic investigation and exploitation of two such reactions.
In PART I, the intramolecular Diels–Alder (IMDA) reaction of aromatic dienes and allene dienophiles, utilized in conjunction with ring-rearrangement metathesis (RRM) to prepare angularly-fused polycyclic lactams, is discussed. The mechanism of the IMDA reaction was investigated with the aid of computational molecular modeling. The reaction was determined to proceed through a concerted mechanism; however, competing radical pathways accounted for stereochemical infidelity and fragmentation observed for some substrates.
An improved, modular synthesis of the precursors was developed to directly couple aromatic amines with the allene fragment precursor, which allowed for the preparation of a small library of heterocyclic compounds. This two-step protocol generates topologically interesting structures, containing two or more new rings, and two new sp3 stereocenters. Computational modeling also guided the development of the unknown analogous reaction for allenyl ketone substrates, which yield carbocyclic products.
Unexpected stereoselectivity and reactivity observations were made in the alkene metathesis reaction, which could not be readily explained. Computational studies were able to elucidate a subtle yet fundamental relationship between reaction mechanism and length of alkene tether in these types of substrates.
In PART II, efforts toward the synthesis of the alkaloid natural product gelsemine are discussed. The synthetic strategy employs a Zincke aldehyde rearrangement/IMDA cascade previously developed by the Vanderwal lab. Using 4-phenylpyridine as a model system, the expected transformation successfully gives an advanced synthetic intermediate lacking only the oxindole substructure, and the key C3–O4 and C5–C16 bonds present in the target. Elaboration of this intermediate toward the target is detailed.
A number of protected 4-(2-aminophenyl)pyridine analogues were prepared to facilitate oxindole formation and circumvent later stage complications that arose in the model system. These compounds all either failed to undergo Zincke salt formation, pyridinium ring-opening, or subsequent rearrangement/IMDA, thus delineating the synthetic boundaries of this type of chemistry.
32
BILLOT, XAVIER. "Utilisation de la reaction de zincke pour la synthese d'oligomeres lineaires ou macrocycliques de type polypyridinium, analogues de produits marins cytotoxiques. Synthese des (r)-niphatesines c et d, de la motuporamine a et de la (r)-haliclorensine." Paris 11, 1999. http://www.theses.fr/1999PA112334.
Анотація:
La reaction de zincke, developpe au laboratoire pour la synthese de sels de pyridiniums chiraux, a ete utilisee pour effectuer la polymerisation controlee et selective d'un monomere de base 3-(7-heptylamino)-pyridine afin de produire des polymeres de taille definie. Ces derniers sont des analogues d'alcaloides naturels cytotoxiques de la famille des manzamines extraits d'eponges. Cette reaction a ensuite permis la macrocyclisation de ces polymeres pour donner des macrocycles dimeriques, tetrameriques et octameriques de 3-heptylpyridinium. La synthese des niphatesines c et d a ete effectuee a partir du 2r-methylundecenol produit par alkylation asymetrique du n-undecylcamphosultame. La reaction-cle de couplage du noyau pyridine sur la chaine alkyle est la reaction de wittig avec le 3-nicotinaldehyde pour la niphatesine c et la reaction de heck pour la niphatesine d. La reaction de zincke a permis ensuite d'effectuer la synthese d'un dimere macrocyclique comportant deux unites de niphatesines c, puis une comportant une unite de niphatesine c et une de niphatesine d. Le travail s'est poursuivi par la synthese de la motuporamine a et de l'haliclorensine, deux polyamines cytotoxiques comportant chacune un azamacrocycle. Leur biogenese est en relation directe avec les alcaloides de la famille des manzamines. La motuporamine a, triamine de type spermidine comportant un azamacrocycle a treize maillons, est synthetisee a partir de l'azatridecanamine par un double enchainement de condensation avec l'acrylonitrile puis reduction du nitrile en amine. La (r)-haliclorensine, diamine comportant un azacycle chiral a dix maillons, est synthetisee a partir du 2r-methyloctadec-9-en-1-ol, prepare par alkylation asymetrique du n-oleoylecamphosultame, en douze etapes. La reaction-cle est une macrocyclisation en condition de haute dilution d'un tosylamide dont l'alcool terminal est active sous forme de tosylate. Le macrocycle est accompagne du dimere macrocyclique en quantite equivalente. La comparaison du pouvoir rotatoire entre l'haliclorensine naturelle et la synthetique permet de dire que le compose naturel est presque sous forme racemique. Nous proposons de nouvelles hypotheses biogenetiques complementaires a celles deja decrites. Ces hypotheses ont pour point de depart la condensation entre des dialdehydes gras et le malondialdehyde, produits de la degradation des acides gras polyinsatures.
33
Mehmandoust, Maryam. "Synthèse de dihydro-1, 2 pyridines et d'équivalents de sels de dihydro-2, 5 pyridinium à partir d'amines primaires chirales : application à la synthèse énantiosélective de dérivés d'isoquinuclidines et de pipéridines 2-substituées." Paris 11, 1989. http://www.theses.fr/1989PA112254.
Анотація:
Une méthode générale de synthèse des sels de pyridinium N-substitués par différents auxiliaires chiraux, une application de la réaction de Zincke, à partir des amines primaires chirales correspondantes, est décrite. Par réduction au borohydrure de sodium en milieu alcalin, ces sels de pyridinium conduisent aux dihydro-1,2 pyridines correspondantes dont les réactions de cycloaddition avec l'acrylate de méthyle ont été étudiées. Des composés azabicyclo[2. 2. 2]octane (isoquinuclidines), dont la configuration absolue a été établie, sont obtenus avec des e. D. De 20 à 33% et une bonne pureté optique. La réduction des sels de pyridinium dérivés des aminoalcools tel que la (R)-phénylglycinol dans les mêmes conditions conduit aux intermédiaires de type oxazolidine équivalent stable d'un sel de dihydro-2,5 pyridinium. L'alkylation stéréosélective de ces derniers par les réactifs de Grignard, suivie de l'élimination de l’auxiliaire donne accès aux alkyl-2 tétrahydro-1,2,3,6 pyridines optiquement active. L'intérêt de cette méthode générale pour l'élaboration des squelettes pipéridiniques, est illustré par la synthèse de la (R)-(+)-anatabine ainsi que la (S)-(+)coniineThe reaction of chiral primary amines with 2,4-dinitro phenyl pyridinium chloride, according to Zincke's procedure, leads to chiral pyridinium salts which can be reduced with NaBH4 in an alkaline medium to the corresponding 1,2-dihydropyridines bearing the chiral substituent on the nitrogen. Cycloaddition reactions of these dihydropyridines with methyl acrylate give isoquinuclidines in 20-33% d. E. Absolute configuration of optically pure isoquinuclidines separated from this diastereoisomeric mixture is established. On the other hand, reduction of pyridinium salts derived from amino alcohols such as (R)-phenyl glycinol in the same conditions leads to new oxazolidine-type intermediates which can be considered as 2,5-dihydropyridinium salt equivalents. Stereoselective alkylation followed by removal of the chiral auxilliary provides a simple access to enantio merically pure 2-alkyl 1,2,3,6-tetrahydropyridines. The usefulness of this methodology for the construction of optically pure piperidine derivatives is illustrated by the synthesis of (R)-(+)-anatabine and (S)-(+)-coniine
34
Hales, Matthew Cameron. "Synthesis and characterisation of substituted smithsonite and calcite." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/16643/1/Matthew_Hales_Thesis.pdf.
Анотація:
Carbonate minerals play a very important role in nature, they represent some of the most diverse and common mineral species on the Planet. They are directly involved in the carbon dioxide (CO2) cycle acting as relatively stable long term chemical storage reservoirs, moderating both global warming trends and oceanaquatic chemistry through carbonate buffering systems. A range of synthetic metal carbonates have been synthesised for analysis under multiple experimental conditions, in order to study the variation in physical and chemical properties such as phase specificity, metal substitution, hydration/hydroxy carbonate formation under varying partial pressures of CO2 and thermal stability. Synthetic samples were characterised by a variety of instrumental analysis techniques in order to investigate chemical purity and phase specificity. Some of the techniques included, vibrational spectroscopy (IR/Raman), thermal analysis (TGA-MS) (thermal Raman), X-Ray diffraction (XRD) and electron microscopy (SEM-EDX). From the instrumental characterisation techniques, it was found that single phase smithsonite, hydrozincite, calcite and nesquehonite could successfully be synthesised under the conditions used. Minor impurities of other minerals and / or phases were found to form under specific chemical or physical conditions such as in the case of hydrozincite / simonkolleite if zinc chloride was used during hydrothermal synthesis.
35
Hales, Matthew Cameron. "Synthesis and characterisation of substituted smithsonite and calcite." Queensland University of Technology, 2008. http://eprints.qut.edu.au/16643/.
Анотація:
Carbonate minerals play a very important role in nature, they represent some of the most diverse and common mineral species on the Planet. They are directly involved in the carbon dioxide (CO2) cycle acting as relatively stable long term chemical storage reservoirs, moderating both global warming trends and oceanaquatic chemistry through carbonate buffering systems. A range of synthetic metal carbonates have been synthesised for analysis under multiple experimental conditions, in order to study the variation in physical and chemical properties such as phase specificity, metal substitution, hydration/hydroxy carbonate formation under varying partial pressures of CO2 and thermal stability. Synthetic samples were characterised by a variety of instrumental analysis techniques in order to investigate chemical purity and phase specificity. Some of the techniques included, vibrational spectroscopy (IR/Raman), thermal analysis (TGA-MS) (thermal Raman), X-Ray diffraction (XRD) and electron microscopy (SEM-EDX). From the instrumental characterisation techniques, it was found that single phase smithsonite, hydrozincite, calcite and nesquehonite could successfully be synthesised under the conditions used. Minor impurities of other minerals and / or phases were found to form under specific chemical or physical conditions such as in the case of hydrozincite / simonkolleite if zinc chloride was used during hydrothermal synthesis.
36
Dietze, Markus. "Die Lukasevangelien auf Caló. Die Ursachen ihrer Sprachinterferenz und der Anteil des Spanischen." Master's thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-152855.
Анотація:
Die Arbeit behandelt die beiden Übersetzungsversionen des Lukasevangeliums ins Caló, die George Borrow 1837 und 1872 anfertigte. Sie hat mehrere Zielstellungen. Der erste Teil geht der Frage nach: Wie kam es zu den beiden Schriften? Er legt dar, welche Einflussfaktoren das authentische Caló im Spanien der 1830er Jahre herausgeprägt haben konnten und welche Einflüsse durch den Übersetzer George Borrow auf die Übersetzungen wirkten. Als extralinguistische Faktoren wird dafür die (Kultur-)Geschichte der Gitanos herangezogen, werden Borrows Biographie sowie seine Sprachkenntnisse untersucht und werden die Aufsätze namhafter Autoren über die Entstehung des Calós diskutiert und gegeneinander abgewogen. So entsteht zum ersten Mal eine komplexe Zusammenfassung der Vorgeschichte des Calós der Evangelien. Der zweite Teil der Arbeit ist einerseits eine Anleitung, die das Caló anhand von Textbeispielen für Hispanisten lesbar macht, und prüft andererseits, ob und wie die Aussage zutrifft, dass Borrows Purifizierungsbestrebungen in der zweiten Übersetzungsversion ein Caló schufen, das einen wesentlich geringeren Anteil an spanischer Sprache hat als in der ersten Version. Die Frage nach der Purifizierung erscheint vor dem Hintergrund der damaligen verklärenden Zigeunermode, der Afición, in Spanien sowie angesichts des Polyglotten Borrow bedeutsam. Um ihr nachzugehen, werden die ersten siebeneinhalb Kapitel beider Übersetzungen mit Hilfe von Textanalyseprogrammen wortartenspezifisch untersucht. Das Ergebnis bestätigt die Annahme bei zehn von sechzehn Wortarten und zeigt auf, dass besonders bei den Autosemantika Purifizierungsversuche unternommen wurden. Wahrscheinlich war aber schon die erste Übersetzungsversion purifiziert.
Die Arbeit liefert einen ersten detaillierten linguistischen Vergleich eines Teiles der beiden Versionen und stellt das Caló der Evangelien in einem sehr umfassenden Kontext vor, wodurch sich eine Vernetzung linguistischer, kulturwissenschaftlicher und literaturwissenschaftlich interessanter Aspekte ergibt.
37
Wang, Rainey Yu. "The morphology study of zinc electrodeposits from alkaline zincate solutions." 2006. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=449830&T=F.
38
Chen, Po-Wei, and 陳柏瑋. "Preparation calcium zincate composite and its application to a Ni/Zn battery." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/76306082666603047808.
Анотація:
碩士明志科技大學
化工與材料工程研究所
97
The purpose of this work is to improve the life-cycle of a Zn electrode on a secondary Ni/Zn battery. As we know, the application of the secondary Zn electrode on the rechargeable Ni/Zn battery is still limited because of the dendritic growth, the shape change, and the high solubility in a concentrated KOH solution for the Zn electrode. The calcium zincate powders used as active materials (so-called CP-ZnCa) for the secondary Zn electrode were prepared by a chemical co-precipitation (CP) method. The preparation condition of CP-ZnCa active materials was at 60oC and pH=12. Moreover, the CP-ZnCa powders show higher surface area (28.66 m2 g-1) and smaller particle size, and the chemical uniformity of the CP-ZnCa powers was extremely good. The characteristic properties of CP-ZnCa powders were systematically examined by thermal gravimetric analysis (TGA), X-ray diffraction (XRD) analysis, Brunauer-Emmett-Teller (BET) measurement, Transmission electron microscope (TEM), and micro-Raman spectroscopy. As a result, the electrochemical performance of CP-ZnCa powders was much better than that of BM-ZnCa powders. In order to avoid the dendritic growth of the secondary Zn electrode, the zinc electrodes generally need a suitable micro-porous polymer membrane during the charge/discharge process. In this work, we prepared two types of new micro-porous polymer membranes, namely, the micro-porous PVA/PVC and PVA/PEO composite polymer membranes, for the secondary zinc electrode. The secondary zinc electrode by using CP-ZnCa powders coated on the brass screen wrapped with the micro-porous PVA/PVC or PVA/PEO composite polymer membranes was prepared and studied. Using cycle voltammetry to examine the cycle-life of the secondary zinc electrode, it was found that it exhibited at least 200 life-cycle. In addition, the secondary Ni/Zn battery was prepared and examined by using galvanostatic test method at the C/5 charge and the C/5 discharge rates. The experimental result revealed that the secondary Ni/Zn battery showed at least 50 life-cycle; moreover, the current and energy efficiencies of the Ni/Zn battery were about 80% and 70%, respectively.
39
Meng-HanYang and 楊孟翰. "Synthesis and characterization of nano-zincite with different morphologies." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/37611175096721365916.
Анотація:
碩士國立成功大學
地球科學系
102
Zincite (ZnO), which has many potential properties, such as wide direct band gap (~3.37 eV) and high-exciton binding energy (~60 meV), has been widely investigated. In this study, zincite with two crystal morphologies (nano-particle and nano-rod) is synthesized via the chemical precipitation and hydrothermal methods. The zincite nano-particle and nano-rod both have a hexagonal structure with the wurtzite-type. The zincite nano-particle has a particle size around 20~60 nm and nano-rod has a particle size of 15~35 nm in width and 100~150 nm in length, which are fabricated by chemical precipitation method. The zincite micron-rod synthesized via hydrothermal method has a larger particle size of 400~800 nm in width and 800~6,000 nm in length. The band gap of zincite nano-particle and nano-rod is 3.1~3.2 eV. The BET result shows that the specific surface area of the zincite nano-particle and nano-rod is 30.39 m2/g and 23.99 m2/g, respectively. It is also observed that both morphologies of nano-zincites exhibit good photocatalytic activity under UV-light illumination. The photodegradation on methylene blue is ~95 % within 170 and 105 min for zincite nano-particle and nano-rod, respectively. Hence, nano-zincite is a superior photocatalyst, effective for clean removal of organic dyes, and maybe suitable for wastewater treatment applications.
40
Zortea, Laura. "Caratterizzazione microstrutturale e meccanica di rivestimenti colorati innovativi ottenuti tramite bagni di zincatura con l'aggiunta di titanio." Doctoral thesis, 2013. http://hdl.handle.net/11573/917219.
Анотація:
L’uso di rivestimenti in zinco e leghe di zinco sugli acciai è una delle tecniche commercialmente più importanti usate per proteggere i componenti esposti all’ambiente esterno.
Lo scopo di questo lavoro è stato quello di studiare l’effetto del titanio sui rivestimenti zincati, in quanto l’aggiunta di questo elemento comporta una colorazione della superficie.
Si è cercato così di unire l’effetto protettivo della zincatura alla bellezza di una colorazione resa solidale al ricoprimento grazie alla formazione di ossidi superficiali, e ovviare così ai problemi
dei sistemi duplex zincatura‐verniciatura.
I rivestimenti così ottenuti sono stati caratterizzati dal punto di vista strutturale e meccanico, per poterne valutare l’affidabilità e il campo di applicazioni.
41
Monteiro, Fernando Jorge Mendes. "A electrodeposição sobre alumínio : tratamentos prévios em solução modificada de zincato." Doctoral thesis, 1986. http://hdl.handle.net/10216/12781.
42
Monteiro, Fernando Jorge Mendes. "A electrodeposição sobre alumínio : tratamentos prévios em solução modificada de zincato." Tese, 1986. http://hdl.handle.net/10216/12781.
43
Montuori, Mario. "CORROSIONE DI ARMATURE IN ACCIAIO E ACCIAIO ZINCATO SU STRUTTURE IN CALCESTRUZZO ARMATO RINFORZATE CON FRP." Tesi di dottorato, 2008. http://www.fedoa.unina.it/4017/1/montuori%29.pdf.
Анотація:
La valutazione della durabilità e la prevenzione della corrosione delle armature di strutture in calcestruzzo rappresentano, al giorno d’oggi, un argomento critico nello studio di manufatti in calcestruzzo armato. I costi elevati relativi alla manutenzione e al recupero di strutture danneggiate hanno condotto alla consapevolezza che la corrosione delle barre deve essere prevenuta al fine di incrementare la vita utile di un manufatto. Nel presente lavoro si sono studiati i fenomeni di degrado di provini di calcestruzzo armato in presenza di cloruri e di anidride carbonica, in condizioni di libera esposizione e mediante prove di corrosione accelerata, valutando l’influenza derivante dall’applicazione di fibre di carbonio e di vetro sulla superficie esterna di provini cilindrici appena confezionati. E' stato, altresì, valutato il contributo alla riduzione della velocità di corrosione di provini rivestiti con fibre di carbonio e vetro in una fase intermedia del processo di degradazione.
44
"Perda de carga provocada por engate rapido em tubulações de aço zincado." Tese, Biblioteca Digital da Unicamp, 1998. http://libdigi.unicamp.br/document/?code=vtls000184082.
45
Zincke, Horst [Verfasser]. "Zur Alteration der Immunogenität von Nierentransplantaten beim Hund und beim Menschen / vorgelegt von Horst Zincke." 2006. http://d-nb.info/98060477X/34.
46
Cokoja, Mirza [Verfasser]. "Nanometallurgy in organic solution: organometallic synthesis of intermetallic transition metal aluminide and -zincide nanoparticles / vorgelegt von Mirza Cokoja." 2007. http://d-nb.info/985056525/34.
47
Rodrigues, Joana Isabel da Silva. "Recuperação de metais de águas contaminadas por processos baseados na utilização de extratos das plantas Cistus ladanifer e Erica andevalensis." Master's thesis, 2019. http://hdl.handle.net/10400.1/14894.
Анотація:
Atualmente, devido à maior preocupação com os problemas ambientais que consequentemente levam a restrições à descarga de efluentes contaminados com metais, tornou-se essencial o desenvolvimento de processos sustentáveis e eficazes, visando a recuperação dos metais das águas residuais. Simultaneamente, inúmeras espécies vegetais foram descritas como tolerantes e acumuladores de metais, como é o caso de Erica andevalensis e Cistus ladanifer, ambas encontradas em Portugal na mina de São Domingos. Essa capacidade dessas plantas foi explorada no presente trabalho, visando a recuperação de metais de interesse a partir de soluções aquosas. Para essa finalidade, os principais objetivos desta pesquisa foram:
(1) obter extratos das plantas para serem utilizados em efluentes contaminados com metais, para remoção/recuperação dos metais de interesse e
(2) utilizar os compostos destas plantas em solventes orgânicos de forma a testar a sua eficácia para remoção/recuperação de metais pela técnica de extração por solvente (extração líquido-líquido).
Os testes com extratos hidroalcoólicos da planta E. andevalensis e C. ladanifer adicionados a soluções unimetálicas preparadas com HCl e H2SO4, mostraram que os metais do grupo platina (Pt e Pd) e ouro foram removidos (20 a 100%) em ambas as matrizes, bem como prata (90 a 100%) em H2SO4. O mesmo aconteceu com o ferro, mas em menor intervalo de remoção (15 a 25%). Por outro lado, a adição desses extratos a um efluente da eletrozincagem moderadamente contaminado com Zn e Fe resultou apenas em baixa remoção de Fe (≤ 21%). Já na AMD com o extrato de C. ladanifer houve remoção de todos os metais (Al: ~63%, Zn: ~51%, Fe: ~52%, Cu: ~43% e Mn: ~36%); assim como com o extrato de E. andevalensis, apesar de em percentagens mais baixas (Al: ~10%, Zn: ~16%, Fe: ~21%, Cu: ~6% e Mn: ~1%).
Nos testes de recuperação de metais por extração por solventes mostrou que nos extratos de folhas de C. ladanifer preparados com Shell GTL e Octanol ou apenas Shell GTL, houve baixa extração de ferro (<10%) e não houve extração de zinco do efluente da zincagem. Quando se utilizou acetato de etilo enriquecido com compostos fenólicos de C. ladanifer o melhor rendimento em compostos fenólicos foi obtido quando se usou 80% (v/v) de acetona em água acidificada (1,2 M HCl). Verificou-se também uma relação direta entre a concentração de fenóis no acetato de etilo e a eficiência das extrações de ferro e zinco (~34% e ~56%, respetivamente). Nos testes com os compostos fenólicos transferidos para outros solventes orgânicos (butirato de etilo, acetato de butilo, decanol e octanol) as eficiências das extrações de ferro e zinco foram relativamente baixas (<25%) para ambas as plantas.Nowadays, due to the greater concern about environmental problems and considering the restrictions on the discharge of effluents contaminated with metals, it is essential to develop sustainable and effective processes aiming the recovery of metals from waste streams. At the same time numerous plant species have been described as metal tolerant and accumulators, as is the case of Erica andevalensis and Cistus ladanifer, both found in Portugal in the São Domingos mining area. That capacity of those plants has been explored in the present work aiming the recovery of strategic metals from aqueous solutions. To achieve that purpose the main objectives of this research included: (1) to assess the use of hydroalcoholic plant extracts directly in metal contaminated effluents and artificial solutions for the removal / recovery of the metals of interest and (2) to assess the use of phenolic compounds extracted from those plants diluted in organic solvents for the removal / recovery of metals by solvent (also known as liquid-liquid) extraction technique. The tests in which hydroalcoholic extracts of E. andevalensis and C. ladanifer were added to unimetallic solutions prepared with HCl and H2SO4, showed that the platinum group metals (Pt and Pd) and gold were removed (20 to 100%) from both matrices, as well as silver (90 to 100%) in H2SO4. The same happened with iron(III) but in a lower range of removal (15 to 25%). On the other hand, the addition of these extracts to a zinc plating effluent moderately contaminated with Zn an Fe resulted in no removal of Zn and low removal of Fe (≤ 21%). On the contrary, when the hydroalcoholic extract of C. ladanifer was added to an extremely concentrated acid mine drainage (AMD) collected in the São Domingos mining area, all metals were removed in medium percentages (Al: ~ 63%, Zn: ~ 51%, Fe: ~ 52%, Cu: ~ 43% and Mn: ~ 36%); as with the extract of E. andevalensis, albeit in lower percentages (Al: ~ 10%, Zn: ~ 16%, Fe: ~ 21%, Cu: ~ 6% and Mn: ~ 1%). The solvent extraction tests aiming metals recovery from the zinc plating effluent showed that for the extracts of C. ladanifer prepared with Shell GTL and Octanol, or only Shell GTL, there was low extraction of Fe (<10%) and no extraction of Zn from the zinc plating effluent. On the other hand, when using ethyl acetate enriched with C. ladanifer phenolic compounds, the best yield on phenolic compounds was obtained with 80% (v/v) acetone in acidified water (1.2 M HCl) and there was a direct relationship between the concentration of phenols in ethyl acetate and the efficiency of iron and zinc extractions (which reached ~ 34% and ~ 56%, respectively). Moreover, in tests with phenolic compounds transferred to ethyl butyrate, butyl acetate, decanol and octanol, extraction efficiencies of Zn and Fe (<25%) were relatively lower for both plants than when ethyl acetate was used.
Este trabalho foi financiado por fundos nacionais através da FCT - Fundação para a Ciência e Tecnologia - no âmbito do projeto Metalchembio (no. 29251) e do projeto UID / Multi / 04326/2019 e co-financiado pelo Programa Operacional Regional do Algarve (CRESC Algarve 2020), através do Portugal 2020 e do Fundo Europeu de Desenvolvimento Regional (FEDER).
48
Roy, Debangsu. "Exchange Spring Behaviour in Magnetic Oxides." Thesis, 2012. http://etd.iisc.ac.in/handle/2005/3172.
Анотація:
When a permanent magnet is considered for an application, the quantity that quantifies the usability of that material is the magnetic energy product (BH)max. In today’s world, rare earth transition metal permanent magnets like Nd-Fe-B, Sm-Co possesses the maximum magnetic energy product. But still for the industrial application, the ferrite permanent magnets are the primary choice over these rare transition metal magnets. Thus, in the present context, the magnetic energy product of the low cost ferrite system makes it unsuitable for the high magnetic energy application. In this regard, exchange spring magnets which combine the magnetization of the soft phase and coercivity of the hard magnetic phases become important in enhancing the magnetic energy product of the system. In this thesis, the exchange spring behaviour is reported for the first time in hard/soft oxide nanocomposites by microstructural tailoring of hard Barium Ferrite and soft Nickel Zinc Ferrite particles. We have analyzed the magnetization reversal and its correlation with the coercivity mechanism in the Ni0.8Zn0.2Fe2O4/BaFe12O19 exchange spring systems. Using this exchange spring concept, we could enhance the magnetic energy product in Iron Oxide/ Barium Calcium Ferrite nanocomposites compared to the bare hard ferrite by ~13%. The presence of the exchange interaction in this nanocomposite is confirmed by the Henkel plot. Moreover, a detailed Reitveld study, magnetization loop and corresponding variation of the magnetic energy product, Henkel plot analysis and First Order Reversal Curve analysis are performed on nanocomposites of hard Strontium Ferrite and soft Cobalt Ferrite. We have proved the exchange spring behaviour in this composite. In addition, we could successfully tailor the magnetization behaviour of the soft Cobalt Ferrite- hard Strontium Ferrite nanocomposite from non exchange spring behaviour to exchange spring behaviour, by tuning the size of the soft Cobalt Ferrite in the Cobalt Ferrite/Strontium Ferrite nanocomposite. The relative strength of the interaction governing the magnetization process in the composites has been studied using Henkel plot and First Order Reversal Curve method. The FORC method has been utilized to understand the magnetization reversal behaviour as well as the extent of the irreversible magnetization present in both the nanocomposites, having smaller and larger particle size of the Cobalt Ferrite. It has been found that for the all the studied composites, the pinning is the dominant process for magnetization reversal. The detailed structural analysis using thin film XRD, angle dependent magnetic hysteresis and remanent coercivity measurement, coercivity mechanism by micromagnetic analysis and First Order Reversal Curve analysis are performed for thin films of Strontium Ferrite which are grown on c-plane alumina using Pulsed Laser Deposition (PLD) at two different oxygen partial pressures. The magnetic easy directions of both the films lie in the out of plane direction where as the in plane direction corresponds to the magnetic hard direction. Depending on the oxygen partial pressure during deposition, the magnetization reversal changes from S-W type reversal to Kondorsky kind of reversal. Thus, the growth parameter for the Strontium Ferrite single layer which will be used further as a hard layer for realizing oxide exchange spring in oxide multilayer, is optimized. The details of the magnetic and structural properties are analyzed for Nickel Zinc Ferrite thin film grown on (100) MgAl2O4. We have obtained an epitaxial growth of Nickel Zinc Ferrite by tuning the growth parameters of PLD deposition. The ferromagnetic resonance and the angle dependent hysteresis loop suggest that, the magnetic easy direction for the soft Nickel Zinc Ferrite lie in the film plane whereas the out of plane direction is the magnetic hard direction. Using the growth condition of respective Nickel Zinc Ferrite and Strontium Ferrite, we have realized the exchange spring behaviour for the first time in the trilayer structure of SrFe12O19 (20 nm)/Ni0.8Zn0.2Fe2O4(20 nm)/ SrFe12O19 (20 nm) grown on c-plane alumina (Al2O3) using PLD. The FORC distribution for this trilayer structure shows the single switching behaviour, corresponding to the exchange spring behaviour. The reversible ridge measurement shows that the reversible and the irreversible part of the magnetizations are not coupled with each other.
49
Roy, Debangsu. "Exchange Spring Behaviour in Magnetic Oxides." Thesis, 2012. http://hdl.handle.net/2005/3172.
Анотація:
When a permanent magnet is considered for an application, the quantity that quantifies the usability of that material is the magnetic energy product (BH)max. In today’s world, rare earth transition metal permanent magnets like Nd-Fe-B, Sm-Co possesses the maximum magnetic energy product. But still for the industrial application, the ferrite permanent magnets are the primary choice over these rare transition metal magnets. Thus, in the present context, the magnetic energy product of the low cost ferrite system makes it unsuitable for the high magnetic energy application. In this regard, exchange spring magnets which combine the magnetization of the soft phase and coercivity of the hard magnetic phases become important in enhancing the magnetic energy product of the system. In this thesis, the exchange spring behaviour is reported for the first time in hard/soft oxide nanocomposites by microstructural tailoring of hard Barium Ferrite and soft Nickel Zinc Ferrite particles. We have analyzed the magnetization reversal and its correlation with the coercivity mechanism in the Ni0.8Zn0.2Fe2O4/BaFe12O19 exchange spring systems. Using this exchange spring concept, we could enhance the magnetic energy product in Iron Oxide/ Barium Calcium Ferrite nanocomposites compared to the bare hard ferrite by ~13%. The presence of the exchange interaction in this nanocomposite is confirmed by the Henkel plot. Moreover, a detailed Reitveld study, magnetization loop and corresponding variation of the magnetic energy product, Henkel plot analysis and First Order Reversal Curve analysis are performed on nanocomposites of hard Strontium Ferrite and soft Cobalt Ferrite. We have proved the exchange spring behaviour in this composite. In addition, we could successfully tailor the magnetization behaviour of the soft Cobalt Ferrite- hard Strontium Ferrite nanocomposite from non exchange spring behaviour to exchange spring behaviour, by tuning the size of the soft Cobalt Ferrite in the Cobalt Ferrite/Strontium Ferrite nanocomposite. The relative strength of the interaction governing the magnetization process in the composites has been studied using Henkel plot and First Order Reversal Curve method. The FORC method has been utilized to understand the magnetization reversal behaviour as well as the extent of the irreversible magnetization present in both the nanocomposites, having smaller and larger particle size of the Cobalt Ferrite. It has been found that for the all the studied composites, the pinning is the dominant process for magnetization reversal. The detailed structural analysis using thin film XRD, angle dependent magnetic hysteresis and remanent coercivity measurement, coercivity mechanism by micromagnetic analysis and First Order Reversal Curve analysis are performed for thin films of Strontium Ferrite which are grown on c-plane alumina using Pulsed Laser Deposition (PLD) at two different oxygen partial pressures. The magnetic easy directions of both the films lie in the out of plane direction where as the in plane direction corresponds to the magnetic hard direction. Depending on the oxygen partial pressure during deposition, the magnetization reversal changes from S-W type reversal to Kondorsky kind of reversal. Thus, the growth parameter for the Strontium Ferrite single layer which will be used further as a hard layer for realizing oxide exchange spring in oxide multilayer, is optimized. The details of the magnetic and structural properties are analyzed for Nickel Zinc Ferrite thin film grown on (100) MgAl2O4. We have obtained an epitaxial growth of Nickel Zinc Ferrite by tuning the growth parameters of PLD deposition. The ferromagnetic resonance and the angle dependent hysteresis loop suggest that, the magnetic easy direction for the soft Nickel Zinc Ferrite lie in the film plane whereas the out of plane direction is the magnetic hard direction. Using the growth condition of respective Nickel Zinc Ferrite and Strontium Ferrite, we have realized the exchange spring behaviour for the first time in the trilayer structure of SrFe12O19 (20 nm)/Ni0.8Zn0.2Fe2O4(20 nm)/ SrFe12O19 (20 nm) grown on c-plane alumina (Al2O3) using PLD. The FORC distribution for this trilayer structure shows the single switching behaviour, corresponding to the exchange spring behaviour. The reversible ridge measurement shows that the reversible and the irreversible part of the magnetizations are not coupled with each other.
50
Dietze, Markus. "Die Lukasevangelien auf Caló. Die Ursachen ihrer Sprachinterferenz und der Anteil des Spanischen." Master's thesis, 2012. https://tud.qucosa.de/id/qucosa%3A28299.
Анотація:
Die Arbeit behandelt die beiden Übersetzungsversionen des Lukasevangeliums ins Caló, die George Borrow 1837 und 1872 anfertigte. Sie hat mehrere Zielstellungen. Der erste Teil geht der Frage nach: Wie kam es zu den beiden Schriften? Er legt dar, welche Einflussfaktoren das authentische Caló im Spanien der 1830er Jahre herausgeprägt haben konnten und welche Einflüsse durch den Übersetzer George Borrow auf die Übersetzungen wirkten. Als extralinguistische Faktoren wird dafür die (Kultur-)Geschichte der Gitanos herangezogen, werden Borrows Biographie sowie seine Sprachkenntnisse untersucht und werden die Aufsätze namhafter Autoren über die Entstehung des Calós diskutiert und gegeneinander abgewogen. So entsteht zum ersten Mal eine komplexe Zusammenfassung der Vorgeschichte des Calós der Evangelien. Der zweite Teil der Arbeit ist einerseits eine Anleitung, die das Caló anhand von Textbeispielen für Hispanisten lesbar macht, und prüft andererseits, ob und wie die Aussage zutrifft, dass Borrows Purifizierungsbestrebungen in der zweiten Übersetzungsversion ein Caló schufen, das einen wesentlich geringeren Anteil an spanischer Sprache hat als in der ersten Version. Die Frage nach der Purifizierung erscheint vor dem Hintergrund der damaligen verklärenden Zigeunermode, der Afición, in Spanien sowie angesichts des Polyglotten Borrow bedeutsam. Um ihr nachzugehen, werden die ersten siebeneinhalb Kapitel beider Übersetzungen mit Hilfe von Textanalyseprogrammen wortartenspezifisch untersucht. Das Ergebnis bestätigt die Annahme bei zehn von sechzehn Wortarten und zeigt auf, dass besonders bei den Autosemantika Purifizierungsversuche unternommen wurden. Wahrscheinlich war aber schon die erste Übersetzungsversion purifiziert.
Die Arbeit liefert einen ersten detaillierten linguistischen Vergleich eines Teiles der beiden Versionen und stellt das Caló der Evangelien in einem sehr umfassenden Kontext vor, wodurch sich eine Vernetzung linguistischer, kulturwissenschaftlicher und literaturwissenschaftlich interessanter Aspekte ergibt.:o. Vorwort & Danksagung
i. Einleitung
i.i. Begriffsbestimmung
i.ii. Zielsetzung der Arbeit
Teil I: Die Ursachen der Sprachinterferenz in den Lukasevangelien
I.1. Die Geschichte der Gitanos bis ins 19. Jahrhundert
I.1.1. Die prähispanische Phase
I.1.2. Die erste Phase von 1425 bis 1499
I.1.3. Die zweite Phase von 1499 bis 1783
I.1.4. Die dritte Phase im 19. Jahrhundert
I.2. Die Genese des Calós bis ins 19. Jahrhundert
I.2.1. Denkmäler des Calós vor den Evangelien
I.2.2. Die Debatte um die Genese des Calós
I.2.2.1. Caló versus Pidgin-/ Kreolsprachen: Boretzky (1985) und Romero Yantorno
I.2.2.2. Code-Switching, Pogadisierung, Geheimsprachen und Language Intertwining: Bakker & van der Voort (1991)
I.2.2.3. Archaismen, kryptische Formationen, andalusische Merkmale und unabhängige Lexikentwicklung: Bakker (1995)
I.2.2.4. Das katalonische Romaní als Indiz für die zeitliche Einordnung: Boretzky (1992)
I.2.2.5. Das Caló als Alltagssprache und im Vergleich mit anderen Romaní-Dialekten: Boretzky (1998)
I.2.2.6. Von der Alltagssprache zum geheimsprachlichen Vokabular: Bakker (1998)
I.2.2.7. Zusammenfassung der Debatte
I.3. George Henry Borrow
I.3.1. Kurzbiographie
I.3.2. Borrows Romaní-, Spanisch- und Caló-Kenntnisse
Teil II: Der Anteil des Spanischen in den Lukasevangelien
II.1. Texterschließung für Hispanisten
II.1.1. Wörterbücher
II.1.2. Grammatik
II.1.2.1. Caló-Deklinationssuffixe
II.1.2.2. Caló-Hilfsverben
II.1.3. Textausschnitte
II.1.3.1. Textausschnitt 1: Titelseiten und Vorworte Borrows
II.1.3.2. Textausschnitt 2: Lukas 15, 1 - 4 .
II.2. Wortartenspezifische Analyse des Anteils des Spanischen
II.2.1. Vorgehen
II.2.2. Auswertung
II.3. Schluss
Anhänge
Anhang 1: Vergleich des Anteils des Spanischen an den Lukasevangelien 1 - 8,25 auf Caló von 1837 und 1872 in wortartenspezifischen, systematisierten und
kommentierten Wortfrequenzlisten
A.1. Flektierbare Wortarten
A.1.1. Die Artikel
A.1.2. Die Substantive
A.1.3. Die Eigennamen
A.1.4. Die Pronomina
A.1.4.1. Die Personal- und Reflexivpronomina
A.1.4.2. Die Demonstrativpronomina
A.1.4.3. Die Possesivpronomina
A.1.4.4. Die Relativpronomina
A.1.4.5. Die Indefinitpronomina
A.1.5. Die Adjektiva
A.1.6. Die Verba
A.1.7. Die Numeralia
A.2. Unflektierbare Wortarten
A.2.1. Die Adverbien
A.2.2. Die Präpositionen
A.2.3. Die Interrogativa
A.2.4. Die Konjunktionen
A.2.5. Die Interjektionen
Anhang 2: Paralleltexte: Die Lukasevangelien 1 - 8,25 auf Caló von 1837 und von 1872 und das spanische Lukasevangelium 1 - 8,25 übersetzt von Scío
Abbildungsverzeichnis
Quellenverzeichnis
Tabellenverzeichnis