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1
McNair, Craig. "Synthetic approaches to substituted Ca4B-type azo compounds." Thesis, University of Strathclyde, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366902.
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Swan, Paul Lombard. "Synthesis of mixed ligand, water soluble square planar platinum (II) complexes and an investigation of their association with haematin and potential to inhibit the formation of synthetic malaria pigment." Master's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/9782.
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Includes bibliography.To establish their potential as a template for novel anti-malarial drugs, a series of planinum (II) complexes were synthesised, their association with haematin determined in 40 aqueous DMSO, pH 7.4 at 25°C and their ability to inhibit the formation of β-haematin (synthetic malaria pigment) was investigated. The compounds synthesised and investigated contained a platinum (II) ion coordinated to acylthiourea and diimine ligands. The diimines used included both substituted and unsubstituted 2,2’-bipyridines and 1,10-phenanthrolines. 2-phenyl pyridine was also utilised as a ligand. It has been shown that the uncoordinated planar ligands interact weakly with haematin with a log K in the range of 1.9 and 3.3 while the twisted or more sterically hindered ligands show no observable association with porphyrin. A series of complexes having platinum coordinated which was reflected in association constant log K values in the range of 4.8 to 5.8. Using a 1,10-phenanthroline ligand in place of a 2,2-bipyridine ligand increased the association constant of the platinum complex, resulting in this series of complexes having log K values in the range of 5.8 to 6.2. It has been shown that when platinum (II) is coordinated to diimines, it is the electron withdrawing properties of the metal which result in the strong association between the diimine containing complex and haematin. Finally both the complex containing platinum cis to two acylthiourea ligands as well as a platinum complex containing 2-phenyl pyridine were shown to have no observable interaction with haematin.
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Kahya, Sevinc Sevim. "Synthesis And Characterization Of Fluorescent Zinc Phthalocyanine Pigments And Its Combination Pigment With Mica Titania Pig Ment." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615041/index.pdf.
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In the present work, zinc phthalocyanine and tetra nitro substituted zinc phthalocyanine were sytnhesized by using phthalic anhydride and nitro phthalic acid precursor respectively under microwave irradiation. Molecular structures of these pigments were confirmed by FT-IR and UV-visible spectroscopy analyses. Furthermore, these pigments were deposited on mica-titania pigment substrate in dimethyl formamide solvent to obtain the combination pigment. FT-IR analysis was conducted to analyze the deposition of pigments onto the mica-titania surfaces. Fluorescence spectroscopy analysis was performed to observe zinc phthalocyanine, tetra nitro zinc phthalocyanine pigments, and their combination pigment with mica- titania pigments. The surface morphologies of zinc phthalocyanines on the mica titania pigments were investigated by scanning electron microscopy. Optimum deposition temperature and deposition time were determined by v depositing varying amounts of zinc phthalocyanines. The paint samples of these combination pigments were prepared by alkyd based paint formulation. L*a*b* values of the paint samples were determined by color measuring spectrophotometry. The optimum deposition temperature was determined as 120 oC and the optimum deposition time was determined as half an hour and effective deposition was obtained at 120 °C. It is observed that, with the increasing amount of ZnPc, the interaction between ZnPc particles increases and they desorp the surface of mica-titania pigment. The best result was obtained with 0.08 g ZnPc at 120 oC.
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Pegg, N. A. "Synthesis of natural fungal pigments." Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380151.
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Costa, Asenete Frutuoso da. "S?ntese e caracteriza??o de espin?lios a base de Cu, Fe e Cr para pigmentos cer?micos." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12705.
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Inorganic pigment comprises a host lattice, which is part of the chromophore component (usually a transition metal cation) and possible components modifiers, which stabilize, add or restate the properties pigments. Among the materials with spinel, ferrites, and the chromite stand out, because they have broad technological importance in the area of materials, applicability, pigments, catalytic hydrogenation, thin film, ceramic tiles, among others. The present work, pigments containing CuFe2O4, CuCr2O4,e CuFeCrO4, were synthesized by a method that makes use of gelatin as organic precursor using their application to ceramic pigments. The pigments were characterized by X-ray diffraction (XRD), Infrared spectroscopy, scanning electron microscopy (SEM) spectroscopy in the UV-visible and Colorimetry. The results confirmed the feasibility of the synthetic route used, with respect to powders synthesized, there is the formation of spinel phase from 500?C, with an increase in crystallinity and the formation of other phases. The pigments were shown to be crystalline and the desired phases were obtained. The copper chromite have hues ranging from green to black according to the calcination temperature, while the copper chromite doped with iron had brownish. The ferrites showed copper color and darker brown to black, which may indicate an interesting factor because of the importance of black pigment
Pigmento inorg?nico ? formado por uma rede hospedeira, na qual se integra o componente crom?foro (normalmente um c?tion de metal de transi??o) e os poss?veis componentes modificadores, que estabilizam, conferem ou reafirmam as propriedades pigmentantes. Dentre os pigmentos, as estruturas tipo espin?lio se destacam por possuir ampla import?ncia tecnol?gica na ?rea de materiais, com aplica??o em pigmentos, cat?lise de hidrogena??o, filmes finos, revestimentos cer?micos, dentre outros. No presente trabalho, pigmentos contendo CuFe2O4, CuCr2O4,e CuFeCrO4 foram sintetizados por uma nova rota qu?mica usando gelatina como precursor org?nico visando sua aplica??o para pigmentos cer?micos. Os pigmentos foram caracterizados por difra??o de raios X (DRX), espectroscopia na regi?o do Infravermelho, Microscopia eletr?nica de varredura (MEV) espectroscopia na regi?o do UV-Vis?vel e Colorimetria. Os resultados confirmaram a viabilidade da rota de s?ntese utilizada; Com rela??o aos p?s-sintetizados, observase a forma??o da fase espin?lio a partir de 500oC, com um aumento da cristalinidade, bem como a forma??o de outras fases. Os pigmentos se mostraram cristalinos e as fases desejadas foram obtidas. As cromitas de cobre possuem tonalidades que v?o do verde ao preto, de acordo com a temperatura de calcina??o, enquanto que as cromitas de cobre dopadas com ferro obtiveram colora??o marrom. As ferritas de cobre apresentaram cores bem mais escuras, do marrom ao preto, o que ? uma caracter?stica interessante devido ? grande import?ncia dos pigmentos pretos na ind?stria cer?mica
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Hartnell, Regan David. "The synthesis of novel porphyrinoid pigments." Thesis, Queensland University of Technology, 2000. https://eprints.qut.edu.au/37043/6/37043_Digitised%20Thesis.pdf.
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Hughes, Eric M. "Synthesis and characterisation of inorganic pigments." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313210.
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Booth, Douglas Geoffrey. "Synthesis and struture of ultramarine pigments." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250047.
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Gatelytė, Aurelija. "Synthesis and characterization of novel black pigments." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20120402_093928-15742.
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For this doctoral dissertation there were synthesized and observed the black pigments which are important in both – in art and industry. It was the first time when using the sol-gel method in our laboratory were synthesized YFeO3, Y3Fe5O12, CoFe2O4, NiFe2O4, ZnFe2O4 nanocompounds, which latter were fitted for the black pigmentation of the ceramic glazes.Buvo sudaryti modeliniai juodieji pigmentai iš C suodžių ir K2CO3, Ca3(PO4)2, CaCO3 bei Mg3(PO4)2.Vandeniniu zolių-gelių metodu buvo susintetinti įvairūs metalų vienfaziai nanoferatai YFeO3, Y3Fe5O12, CoFe2O4, NiFe2O4, ZnFe2O4, kurie pirmą kartą panaudoti juodaisiais keraminiais pigmentais.
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Stott, Colin Mark. "Synthesis and photoconduction properties of haloanthanthrone pigments." Thesis, Open University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.255409.
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Topuz, Burcu Berna. "Synthesis And Characterization Of Copper Phthalocyanine Deposited Mica Titania Pigment." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611519/index.pdf.
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In the present work, anatase and rutile titanium dioxide (TiO2) coated lustrous mica pigments were prepared by heterogeneous nucleation method. Anatase-rutile phase transformation of the TiO2 on mica substrate was achieved by coating very thin layers of tin (IV) oxide on mica surfaces prior to TiO2 deposition. Muscovite mica, which was used in the experiments was sieved, pre-treated with sodium bicarbonate and decantated before coating process. The surface morphology of mica titania pigments and anatase-rutile phase transformation were investigated by SEM and XRD analyse, respectively. Also, microwave-assisted synthesis of copper phthalocyanine and tetracarboxamide copper phthalocyanine pigments were carried out with phthalic anhydride and trimellitic anhydride precursors, respectively. Molecular structures of these pigments were confirmed by FT-IR and UV-visible spectroscopy analyse. Furthermore, combination pigments were obtained by the process of deposition of copper phthalocyanine pigments on mica-titania pigment substrate in dimethyl formamide solvent. FT-IR analysis and XRD analyse were performed to observe the transformations in the crystal forms of copper phthalocyanines on the substrate. The surface morphologies of copper phthalocyanines on the mica titania pigments were investigated by SEM analysis. Varying amounts of copper phthalocyanines were deposited on the mica surfaces, and nitrogen elemental analysis was performed to determine the amount of copper phthalocyanines. The resulting pigments were incorporated into alkyd based resin to prepare paint samples. L*a*b* values, gloss property, and hardness of the paint samples were determined by color measuring device, gloss meter and hardness measuring device, respectively.
The resulting combination pigments obtained in this study showed improved luster, hue, and color intensity. Furthermore, in literature it was reported that these pigments have very high bleed resistance. This can be attributed to large macromolecular structure of copper phthalocyanine on the surface of mica titania pigment that prevents bleeding of the pigment from the paint. Moreover, the paint samples obtained from combination pigments showed higher hardness with respect to the paint sample of the mica titania pigment.
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Owens, Craig. "Synthesis and structural characterisation of mixed-metal oxide pigment systems." Thesis, University of Southampton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419147.
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Tabarya, Daniel. "Studies of the Membrane and DNA Gyrase Inhibiting Antibiotics on Pigment Synthesis in Corynebacterium Poinsettiae." Thesis, University of North Texas, 1988. https://digital.library.unt.edu/ark:/67531/metadc935771/.
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The purpose of this study was (1) to determine whether a correlation exists among the protein profiles, extracted from cell membranes of mutants belonging to five pigment cluster groups, (2) to locate the protein moiety and cartenoprotein complex in the membranes of wild type and colorless mutant (designated W-19) of C. poinsettae and to show whether there are any structural differences between cell membranes of the wild type and a colorless mutant, (3) to determine the effect of six antibiotics on cartenoid gene expression.
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Crow, M. A. "The genetic regulation of pigment and antibiotic synthesis in Serratia sp." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598191.
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Serratia sp. strain ATCC 39006 ('39006') produces a bright red pigment prodigiosin (Pig), and a carbapenem antibiotic, 1-carbapen-2-em-3-carboxylic acid (Car). Recently it was shown that 39006 also produced N-acylhomoserine lactones (AHL), which act as quorum sensing (QS) signalling molecules. The notion that 39006 used a QS system to regulate phenotypes according to cell-density was investigated and characterised here. N-butanoyl-L-homoserine lactone (BHL) and N-hexanoyl-L-homoserine lactone (HHL) were identified as the QS signalling molecules by thin-layer chromatography. Ahl- mutants carrying mini-transposon insertions in a single ORF (smaI) were concomitantly deficient in the production of Pig, Car, 'white-opaque phenotype' and the synthesis of the extracellular enzymes pectate lyase and cellulase, all of which were restored by the addition of synthetic AHLs. All five phenotypes were also restored in the smaI- mutant when grown with or near a BHL/HHL-producing strain. It was therefore concluded that 39006 possessed a previously uncharacterised QS system that played a central role in exoenzyme and secondary metabolite production. The smaI gene was sequenced and found to encode a protein (SmaI) similar to members of the LuxI family of AHL synthases. DNA sequencing also revealed another ORF, smaR, which encoded a protein (SmaR) similar to the LuxR family of QS response regulator proteins. The regulation of Pig and Car production with respect to quorum sensing was investigated in this study using lacZ transcriptional fusions to pigA, pigH (pig biosynthetic gene cluster) and carA (car biosynthetic gene cluster). Data supported a model in which the smaIR locus formed a complete regulatory switch where SmaR acted as a repressor of gene transcription at low cell density. At high cell-density, in the presence of AHLs, SmaR-mediated repression was lifted thus allowing transcription.
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Hirst, James Peter. "The synthesis and characterisation of new inorganic pigments." Thesis, University of Liverpool, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415659.
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The synthesis, characterisation and testing of materials as new inorganic blue, red and infrared-reflecting black pigments is presented. A previously unpublished route to the synthesis of microcrystalline KCoAI(P04)2 has been developed and the structure (monoclinic e2k) of the material produced has been verified by refinement against powder neutron diffraction and powder X-ray diffraction. Cs2C02AI(P04)3 displays a chiral colouring of the polyhedral pollucite network and is the first example of a transition metal-loaded material synthesised at high temperature to do so. Refinement of the structure against powder neutron diffraction and powder X-ray diffraction suggests that the tetrahedral sites are fully ordered, with P(V) on one and Co(II)/AI(III) on the other. Rb2C02AI(P04)3 has rhombohedral symmetry at room temperature (R32) and undergoes a phase transition with increased temperature, which is complete by 500°C, yielding a chirally decorated cubic phase akin to that of Cs2C02AI(P04)3. KCoAI(P04h, Cs2C02AI(P04)3, and Rb2C02AI(P04)3 react to lose their intense blue colours when fired in tableware glazes, and lack opacity when fired in glass enamels. The materials are stable as suspensions in PVC, indicating their potential as pigments in plastics. The ability of some chromium-doped pyrochlore materials to act as red inorganic pigments has been explored. The material Y2Th-xCrx07-o has been synthesised with maximum doping represented by Y2Ti1.84CrO.1607-0, which has a red-brown colour. Y2Sn2-xCrx07-0 has been synthesised where x = 0.02, 0.04, and 0.08. These materials are shades of pink, with colour intensity increasing with doping. The material Y2Th-xSbx/2Crx/207-0 has been synthesised where x = 0.25, 0.5 ... 1.75, giving colours ranging from brown to green. Refinement of the structures against powder X-ray diffraction suggests a solid solution between Y2Th07 and YSbCr07. Upon increased levels of doping the M-O bond distances at the mixed metal site increase, as does the extent of trigonal distortion. This is accompanied by a reduction in distortion at the yttrium site. Differences in the colour between these pyrochlores probably arise from a combination of the Cr-O bond compression, and distortion at the octahedral site. Y2Snl.92CrO.OS07-0 was tested on ceramic unglazed tiles, and also in a glass enamel, retaining its colour and providing a glossy finish on both. On glass the material showed less stability in a bismuth-free enamel, but retained its colour well in a bismuth-containing enamel. Y2Til.s4Cro.1607-o lacks stability on tile glazes and glass enamels. BhMn3FeOIO, Bi2Mn3Ti03, BhMn3.7SAlo.2S01O, DyMn20s and ErMn20S have been synthesised as analogues to the infrared reflecting pigment Bi2Mfi401O. Of these, BhMn3.7SAlo.2S01O offers superior reflectance. The spinel and ilmenite phases ZnNil_xFexTi04 and Nil-xFexTi03 are reported (where x = 0.1, 0.3 ... 0.9), and assessed to be poorer reflectors than BhMfi401O. Of most interest with regard to infrared-reflecting black materials has been the synthesis of Bi2Mn3.7sAlo.2S01O, which offers greater reflectance than the commercial pigment BhMfi401 (). and is also not covered by patent law.
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Wood, Pamela. "Synthesis and characterisation of Bismuth orthovanadate." Thesis, University of Aberdeen, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386303.
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A wide range of lime green/yellow to mustard/orange bismuth orthovanadate samples were prepared via solid state and precipitation techniques. The materials were characterised using thermal analysis, X-ray diffraction, evolved gas analysis, reflectance infra-red spectroscopy, electron microscopy, colour measurement, wet chemical analysis and ac impedance spectroscopy. This product characterisation identified more complex materials than previously reported, with generally non-stoichiometric compositions established. The fergusonite-type polymorph of BiVO4 was prepared via solid state synthesis. This phase was found to be slightly V-rich in composition, of BiV1.025O4+x. It occurs as a line composition and melts congruently at 930°C ± 10°C. A reversible, non-quenchable phase transition from fergusonite to scheelite-type BiV1.025O4 + x was determined at 240-250°C. The zircon and scheelite-type polymorphs of BiVo4 were produced by controlled room temperature precipitation, at pH 1-2 and 3-7 respectively, whereas the fergusonite-type polymorph was obtained at pH 1-7 on precipitation from solutions at 95°C. All three precipitated polymorphs were found to contain a proportion of foreign ions, totalling 2.0-3.0, 2.7-3.6 and 0.3-0.9 weight% for the zircon, scheelite and fergusonite-type polymorphs respectively. These foreign ions consist of adsorbed water and structural nitrate, carbonate and hydroxyl constituents. Chemical analysis identified essentially Bi-rich compositions for the precipitated polymorphs. An irreversible phase transition from zircon to scheelite-type BiVO4 was determined at 500-520°C. BiVO4 is studied as a possible alternative yellow pigment for the toxic cadmium and chrome-containing traditional yellow colourants. The sample colours obtained were compared with those of the commercial CdS, PbCrO4 and BiVO4/Bi2MoO6 pigments. Polycrystalline, phase pure BiV1.025O4 + x ceramics, prepared by solid state synthesis were investigated using ac impedance spectroscopy. These materials were found to exhibit mixed oxide ion/electronic conduction at both low and high temperatures, ie. <400°C and >600°C. Oxide ion conductivity dominates the temperature region between 400 and 600°C, with an activation energy of 0.80 + 0.01eV. The bulk conductivity below 400°C was found to be metastable and influenced by the presence of water. The possibility of protonic conduction below 400OC is identified.
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Ivaniuk, H. "Synthesis of brown pigments iron-zink spinel from hydroxide." Thesis, Sumy State University, 2016. http://essuir.sumdu.edu.ua/handle/123456789/52658.
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When cleaning ferumcontained wastewater produced iron (III) hydroxide, which can be disposed in the manufacture of brown mineral pigment.
Brown pigments synthesized with obtaining simple spinels Mg[Fe2]O4, Zn[Fe2]O4 and mixed spinel (Zn, Mg)[Fe2]O4.When using metal hydroxides, especially precipitators that may have an increased reaction capacity, brown pigment synthesis is the reaction:
Zn(OH)2 + Fe(OH)3 = Zn(x-1)Fey[ZnxFe(2-y)]O4 + 3H2O.
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Rugen-Hankey, Sarah. "Synthesis of phthalocyanines for dye sensitized solar cells and stabilised pigment systems." Thesis, Swansea University, 2010. https://cronfa.swan.ac.uk/Record/cronfa42591.
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This thesis reports the synthesis of novel phthalocyanine based photosensitizers for DSSC devices. Key precursors, halogenated phthalonitriles have been synthesised and characterised, which included a novel periodic acid method for forming 4,5-diiodophthalonitrile. Phthalonitrile derivatives with functionalities were synthesised from halogenated phthalonitriles via palladium cross coupling reactions. A novel fumaronitrile anchoring group was synthesised from commercially available methyl 4-(cyanomethyl)-benzoate along with the literature compound 4,5-bis(4-methoxycarbonylphenyl) phthalonitrile. Negishi coupling of 1,1'-dibromo- and ethynylerrocene compounds to halogenated phthalonitriles are also described and characterised along with the synthesis of the solubilising group nonoxyphthalonitrile. The effectiveness of the subphthalocyanine and statistical cyclotetramisation routes to phthalocyanine synthesis using the substituted phthalonitiles has been investigated in the preparation of substituted azapoiphyrines and unsymmetrical phthalocyanines. The dyes contained different donor (r-butyl and nonoxy) and acceptor (carboxylic acid) functional groups, especially designed for sensitisation in DSSC devices. Ring expansion reaction of the subphthalocyanines was very dependent on the substituent and reaction conditions and, in many cases, was not a selective process. Statistical cyclotetramisation of mixed substituted phthalonitriles formed pseudo statistical mixtures where it proved hard to separate the individual compounds from each other. Both the substituted azaporphyrines and unsymmetrical phthalocyanine dyes were used to sensitise naonparticular titiania and constructed into DSSC devices, in which IV and IPCE curves have been measured for each dye. DSSC photoactivity was observed for each unsymmetrical substituted dye. This thesis also describes the synthesis and characterisation of magnesium-aluminium layered double hydroxide clays which, in turn, were used in the preparation of phthalocyanine-suppoited and phthalocyanine-intercalated layered double hydroxides. These substituted clays were then used for the preparation of stabilised pigment systems and were incorporated into model paint formulations based on a PVC matrix. Degradation studies were earned out using the CO2 Flat Panel Reactor using UV irradiated panels coated with the paint formulations. The effect of clay particle morphology, clay particle size, clay-pigment preparation method and pigment loading concentration were all investigated with results showing that > 5 % pigment loading was required to reduce PVC degradation rates. Reflectance measurements were also used to monitor degradation of the panels.
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Doksa, Alexander P. "Synthesis of Iron Oxide Pigment from the Treatment of Truetown Acid Mine Drainage Utilizing Aeration." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1420801380.
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Kumar, Swati. "Optical and vibrational spectroscopic studies of synthetic Maya pigments as a function of concentration of indigoid dyes." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Boothman, Stuart Roy. "The effect of high temperature on lycopene synthesis and degradation in tomato fruit (Lycopersicon esculentum)." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365895.
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Bories-Azeau, Xavier. "Synthesis of novel block copolymer dispersants for water-borne pigments." Thesis, University of Sussex, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.555262.
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Joll, Cynthia Ann. "The asymmetric synthesis of isochromans related to the aphid pigments." Thesis, Joll, Cynthia Ann (1995) The asymmetric synthesis of isochromans related to the aphid pigments. PhD thesis, Murdoch University, 1995. https://researchrepository.murdoch.edu.au/id/eprint/51655/.
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Many of the naturally occurring benzoisochromanquinones exhibit notable biological activity, being potential antibiotics or antineoplastic agents. The synthetic work described in this thesis is directed towards the asymmetric synthesis of Quinone A 2, Quinone A 3 and Deoxyquinone A 4, three derivatives of the naturally occurring benzoisochromanquinone aphid pigments, protoaphin-fb, protoaphin-sl and deoxyprotoaphin, respectively.
In the first chapter, a comprehensive review of a category of benzoisochromanquinone natural products related to the aphid pigment derivatives is presented, highlighting their structures, occurrence and biological activities. This is followed by a discussion of the isolation and structural elucidation of the aphid pigments themselves. The racemic synthesis of the aphid pigment derivatives 2, 3 and 4, and the asymmetric syntheses of several related naturally occurring benzoisochromanquinones are reviewed in the latter part of the chapter.
An approach to the first chiral synthesis of Quinone A 2, Quinone A' 3 and Deoxyquinone A 4, through a key intermolecular reaction between a metal phenolate and a chiral aldehyde, is detailed in Chapter Two.
It was first necessary to prepare an aromatic compound which is a suitable precursor to the benzyne 189. The assembly of two different precursors is described, and the yields of their respective conversions to the intermediate benzyne 189 and in situ cycloaddition reaction with 2-methoxyfuran compared.
Model studies of the key intermolecular reaction, using 4,5,7-trimethoxynaphthalene-1-ol and the 1-ethoxyethyl ether of (2S)-2-hydroxypropanal, are then presented. This reaction was highly diastereoselective and this was controlled by the choice of the metal. Thus, the product of addition of the titanium phenolate differed from that of the magnesium phenolate only at the newly created chiral centre.
Chapter Three deals with the application of the reaction between metal phenolates and chiral aldehydes to intramolecular processes. Firstly, commercially available 2,5-dihydroxyacetophenone was transformed into the differentially protected 5-benzyloxy-2-methoxyacetophenone. This was followed by extension of the side chain by formation of an ether with (S)-ethyl lactate. Ultimately, two diastereomeric optically-pure phenols, each bearing an aldehydic side chain derived from (S)-ethyl lactate, were prepared.
These were each treated separately with both titanium tetraisopropoxide and ethyl magnesium bromide and the products of the four reactions examined in detail. In the case of the bromomagnesium phenolates, the yields of cyclized products were poor, and for one of these diastereomeric phenolates the stereoselectivity of cyclization was only average. For the titanium phenolates, high yields of products of intramolecular cyclization were obtained. The diastereoselectivity of the cyclization reaction was only 3:1 in one case, but in the other, which produced the required benzopyran analogous to Quinone A, the cyclization was completely diastereoselective. Thus, the first chiral synthesis of a benzopyranquinone having the same absolute stereochemistry as the enantiomer of Quinone A, i.e., quinone 234, is presented.
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Oosthuizen, Francois Jacobus. "Synthesis of hongconin and related naphtho[2,3-c]pyrans." Thesis, Cape Technikon, 1995. http://hdl.handle.net/20.500.11838/746.
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Thesis (MTech(Chemistry))--Cape Technikon, Cape Town,1995The naphtho[2,3-c]pyran occurs frequently in nature as derivatives of the 5,10 quinones. The most common examples include the eleutherins and protoaphins. These naturally occurring compounds have been found to possess antibiotic activity through the process of bioactivation. The possibility of appropriately substituted compounds functioning as bioreductive alkylating agents provides a logical model that has a great deal of predictive power. The thesis deals with the synthesis of some naphtho[2,3-c]pyrans to be tested biologically; the challenge being to design compounds in a biologically inactive form which become activated only subsequent to an in-vivo transformation. Chapter One describes and compares a high yielding synthesis of a naphtho[2,3c] pyran, hongconin, to a previous route.,a Racemic hongconin (29) has been synthesised from adduct (43) formed by reaction between 1-methoxycyclohexa1,4- diene (41) and 1,4-benzoquinone (42). The key steps includes Fries and Claisen rearrangements, base and cerium(lVj initiated pyran ring formation, C-4 pyran ring hydroxylation and silver(ll) mediated oxidation. The target compound (29) was tested in vitro for antimicrobial activity and compared to the results obtained for isoeleutherin (2) and its 9-demethoxy analoque (30). The spectral data, melting points and yields of the individual compounds is as described in Chapter Two.
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Keates, Adam. "The design and synthesis of near infra-red absorbing inorganic pigments." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/380915/.
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Materials which exhibit strong absorption in the Near Infra-Red (NIR) region have applications as laser-marking pigments, IR filters in photovoltaics and CCD detectors, medical imaging devices and absorbing coatings in solar thermal collectors. New NIR absorbing materials based on iron (II) and copper (II) frameworks have been designed using knowledge of predicted d-energy levels and associated transitions. Materials from this class have been synthesised and characterised in terms of structure and optical properties A family of 13 iron phosphates and fluorophosphates have been obtained using hydrofluorothermal routes and characterised using single crystal X-ray diffraction. These materials show a variety of structural elements with one-, two- and three-dimensional connectivity. For example RbFe3(PO3F)2(PO2(OH)2)F2 has a framework structure consisting of face-sharing FeO4F2 octahedra linked by PO3F tetrahedra, which are orientated such that the fluoride are terminal and line inter-framework space. This includes the first example of a hydrothermally synthesised iron chlorofluorophosphate, (NH4)2Fe(II)Fe(III)(PO3F)2FCl2, which contains sheets of FeIIO2Cl4 octahedra linked together by edge-sharing chloride and chains of FeIIIO4F2 octahedra trans linked by μ2-bridging fluoride. UV/Vis/NIR spectra have been collected for 49 compounds and correlations between structure and NIR absorbing properties have been derived. A trend in ligand fields across the series SiO4, PO4 SO4 determined SiO4 showing the weakest ligand field making compounds with this ligand most suitable for NIR absorbing applications. Eight of the most promising materials have been tested for their laser-marking properties using a Nd:YAG laser at Merck, Darmstadt. The effect of particles size on the optical and laser-marking properties has been investigated using K2FeP2O7 as an example. The decrease in particle size caused a red-shift in the absorbance maxima, and produced a well dispersed pigment within the test polymer matrix. Out of these eight compounds, Cu2PO4OH and Cu4PO4O exhibited laser-marking properties comparable to other commercial Merck NIR absorbing pigments.
26
Ward, Christopher. "The production of synthetic rutile and by-product iron oxide pigments from ilmenite processing." Murdoch University, 1990. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070831.150010.
Full textAbstract:
A study has been carried out on the Becher and Summit
Processes with the aim of understanding the mechanism and critical
parameters required for the production of a range of pure iron oxide
pigments, as well as high quality synthetic rutile from reduced
ilmenite .
The Becher Process currently produces a large quantity of
worthless mixed phase iron oxides. However, this study has shown that
the range of iron oxides formed are all derived from the
transformation of lepidocrocite (y-FeOOH) through the solution phase
in iron(II) solutions. The results of a kinetic study of the
transformation of lepidocrocite found that the rate exhibited an
induction period at low pH, was dependent on temperature and was
linearly related to log [H+] and log [Fe2+]. The rate determining step
was found to be the formation of suitable product nuclei, following
dissolution of the initial oxide at the surface of the crystal
lattice.
An electrochemical study of these reactions showed that the
product formed from the transformation of lepidocrocite was a function
of the solution potential and an experimental Eh-pH diagram was
constructed to predict the iron oxide phase produced from hydrolysis
and transformation reactions. The results from this fundamental study
were then applied on both a laboratory and plant scale to produce pure
iron oxide phases.
A modified Summit Process, involving the removal of metallic
iron from the porous reduced ilmenite matrix using FeCl 3, regeneration
of iron(III) and the production of pure iron oxide pigments from the
waste iron(II) chloride solution, was also investigated in detail.
A kinetic study of pure iron dissolution in iron(III)
solutions, comparing three electrochemical techniques and a standard
solution sampling method, gave consistent rate constants provided
allowance was made for the reaction with the proton. The iron
dissolution mechanism was found to be iron(III) diffusion controlled,
while the dissolution in HC1 was under mixed control. A study using
both pure iron and pressed reduced ilmenite discs found that acid
consumption could be minimised by the addition of citrate or by the
addition of A1 3+ or Fe 2+ , which are believed to block the adsorption
of the proton. It was found that iron(III)-citrate complexes inhibited
iron(II1) hydrolysis in the reduced ilmenite pores and enhanced the
purity of the synthetic rutile product.
A study of the oxidation of iron(II) by atmospheric oxygen
using copper(II) and activated carbon catalysts found that these
catalysts were inefficient for complete iron(III) regeneration. The
heating of carbon in the presence of cu2+ was found to enhance the
initial rate of iron(II) oxidation, however it is believed that
surface oxide redox couples formed on the carbon control the iron(II)/
iron(III) ratio in solution, and prevent complete iron(I1) oxidation.
The production of iron oxide pigments under the controlled conditions
afforded by the Summit Process, resulted in superior quality pigments
than are presently attainable from the Becher Process. However,
controlled ageing and crystal growth using waste lepidocrocite from
the Becher Process would result in similar quality pigments being
produced.
27
Ward, Christopher B. "The production of synthetic rutile and by-product iron oxide pigments from ilmenite processing /." Access via Murdoch University Digital Theses Project, 1990. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070831.150010.
Full text
28
Ward, C. B. "The production of synthetic rutile and by-product iron oxide pigments from ilmenite processing." Thesis, Ward, C.B. (1990) The production of synthetic rutile and by-product iron oxide pigments from ilmenite processing. PhD thesis, Murdoch University, 1990. https://researchrepository.murdoch.edu.au/id/eprint/389/.
Full textAbstract:
A study has been carried out on the Becher and Summit Processes with the aim of understanding the mechanism and critical parameters required for the production of a range of pure iron oxide pigments, as well as high quality synthetic rutile from reduced ilmenite.
The Becher Process currently produces a large quantity of worthless mixed phase iron oxides. However, this study has shown that the range of iron oxides formed are all derived from the transformation of lepidocrocite (y-FeOOH) through the solution phase in iron(II) solutions. The results of a kinetic study of the transformation of lepidocrocite found that the rate exhibited an induction period at low pH, was dependent on temperature and was linearly related to log [H+] and log [Fe2+]. The rate determining step was found to be the formation of suitable product nuclei, following dissolution of the initial oxide at the surface of the crystal lattice.
An electrochemical study of these reactions showed that the product formed from the transformation of lepidocrocite was a function of the solution potential and an experimental Eh-pH diagram was constructed to predict the iron oxide phase produced from hydrolysis and transformation reactions. The results from this fundamental study were then applied on both a laboratory and plant scale to produce pure iron oxide phases.
A modified Summit Process, involving the removal of metallic iron from the porous reduced ilmenite matrix using FeCl 3, regeneration of iron(III) and the production of pure iron oxide pigments from the waste iron(II) chloride solution, was also investigated in detail.
A kinetic study of pure iron dissolution in iron(III) solutions, comparing three electrochemical techniques and a standard solution sampling method, gave consistent rate constants provided allowance was made for the reaction with the proton. The iron dissolution mechanism was found to be iron(III) diffusion controlled, while the dissolution in HC1 was under mixed control. A study using both pure iron and pressed reduced ilmenite discs found that acid consumption could be minimised by the addition of citrate or by the addition of A1 3+ or Fe 2+ , which are believed to block the adsorption of the proton. It was found that iron(III)-citrate complexes inhibited iron(II1) hydrolysis in the reduced ilmenite pores and enhanced the purity of the synthetic rutile product.
A study of the oxidation of iron(II) by atmospheric oxygen using copper(II) and activated carbon catalysts found that these catalysts were inefficient for complete iron(III) regeneration. The heating of carbon in the presence of cu2+ was found to enhance the initial rate of iron(II) oxidation, however it is believed that surface oxide redox couples formed on the carbon control the iron(II)/ iron(III) ratio in solution, and prevent complete iron(I1) oxidation. The production of iron oxide pigments under the controlled conditions afforded by the Summit Process, resulted in superior quality pigments than are presently attainable from the Becher Process. However, controlled ageing and crystal growth using waste lepidocrocite from the Becher Process would result in similar quality pigments being produced.
29
Kedy, Pulcherie. "Contribution à l'étude de la 5-aminolévulinate déshydratase chez le radis et un mutant chlorophyllien de tabac." Rouen, 1996. http://www.theses.fr/1996ROUES049.
Full textAbstract:
La 5-aminolévulinate deshydratase (E. C. 4. 2. 1. 24 ; 5-ALAD) est une enzyme oligomérique qui permet la synthèse du porphobilinogène à partir de l'acide aminolévulinique. Son étude après différents traitements par des antibiotiques, des plantules de radis, montre après une analyse par des techniques immunochimiques, une relation étroite entre l'activité enzymatique et la quantité de protéines. Le traitement par la gabaculine induit une inhibition d'environ 75% de l'activité 5-ALAD, ainsi qu'une augmentation de la concentration endocellulaire de l'α-cétoglutarate par rapport à un témoin non traité. Ce cétoacide est un précurseur de l'acide glutamique dans les chloroplastes. Un rôle régulateur de ce cétoacide in vivo sur la synthèse des chlorophylles, est envisagé. L'analyse de la 5-ALAD par des techniques d'immunoempreintes fait apparaître des sous-unités de tailles différentes (37 et 40 kDa) aussi bien chez le radis que chez le tabac. Cependant, seul le tabac sauvage montre une bande immunodétectée a 55 kDa. Différentes hypothèses sur son rôle et son identité sont envisagées en relation avec les travaux récents. L'étude de la 5-ALAD extraite des deux souches de tabac montrent, chez le mutant albinos une activité enzymatique supérieure d'un facteur 6 à celle du tabac sauvage.
30
Huang, Hsiang-Yu. "Synthetic and structural studies of high performance naphtholazo red pigments in relation to application performance." Thesis, Heriot-Watt University, 2008. http://hdl.handle.net/10399/2181.
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31
Walsh, Amy. "Synthesis and analysis of poly(methacrylic acid-co-benzyl methacrylate) copolymers for stable aqueous pigment dispersions." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6457/.
Full text
32
Asmaoglu, Serdar. "Synthesis And Charaterization Of Multi-hollow Opaque Polymer Pigmets." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614539/index.pdf.
Full textAbstract:
In the present work, a new generation opaque polymer pigment with multihollow structure was synthesized by suspension polymerization of &ldquoWater-in-Oil-in-Water&rdquo
(W/O/W) emulsion system. Oil phase was methyl methacrylate and ethylene glycol dimethacrylate monomer mixture at 1:1 weight ratio. The dimension and distribution of hollows inside polymer particles are dependent on the size of water droplets which are encapsulated in micelles. For Water-in-Oil (W/O) assembly, a hydrophobic surfactant and hydrophilic co-surfactant (Span 80-Tween 80) combination with a hydrophilic/lipophilic balance (HLB) value between 5-8 was used. The effects of surfactant and co-surfactant composition on the stability of the W/O emulsion and also on the size of water droplets were studied. In addition, the effect of the ultrasonication on the average size of water droplets was investigated. The hollow size distribution which may possibly give the maximum scattering efficiency was predicted by a mathematical model based on the Mie scattering. The optimum size distribution for W/O emulsion was obtained at the monomer/surfactant/water ratio of 75.5/9.4/15.1 after ultrasonication for 30 seconds at 80 W power. The W/O/W emulsion was prepared by dispersing the W/O emulsion in aqueous solution of hydrophilic Triton X-405. The influence of surfactant concentration and mechanical mixing on monomer droplets was investigated by size measurement and optical microscopy. After stabilizing with 1 %w/w polyvinylpyrrolidone (PVP) solution, the W/O/W emulsion was polymerized at 55 °
C for 20 h. The surface morphology of synthesized polymer pigments was analyzed by scanning electron microscopy (SEM) and the inner hollow structure was confirmed by transmission electron microscopy (TEM). The analysis indicated that multihollow opaque polymer pigments were successfully synthesized. The opacity, the L*a*b* color, and the gloss properties of polymer pigments were examined by spectrophotometer and glossmeter. The opacity values were assessed by contrast ratio measurements, and the synthesized polymer pigments provided up to 97.3 % opacity (50 %v/v solid content). In addition, the pigments exhibited low gloss values, and yielded matt films.
33
Wilson, Anthony James. "Synthesis of novel inhibitors of CDK 4 / Cyclin D1 based on the natural marine sponge pigment fascaplysin." Thesis, University of Leicester, 2009. http://hdl.handle.net/2381/4531.
Full textAbstract:
This thesis describes an investigation into the design and synthesis of novel inhibitors of the cell-cycle regulatory enzyme CDK4/Cyclin D1 utilising the structure of the natural product fascaplysin as a lead compound. The structure activity relationship of fascaplysin (i) has been investigated and its structure simplified and rationalised to give novel inhibitor pharmacophores based on structures (ii) and (iii). Inhibitors of structure (ii) were found to possess activity against CDK4/Cyclin D1 of IC50 51-176 μM and to be approximately 15-20 fold selective over CDK2/Cyclin A. The second generation compounds of structure (iii) were synthesised to explore a suspected π-stacking pocket in the active site of CDK4 around the Phe93 residue. These compounds were active against CDK4/Cyclin D1 with IC50 values in the range 7-50 μM and to be 20-100 fold selective over CDK2/Cyclin A. New methodology towards the synthesis of un-natural products bearing a carbohydrate subunit connected via the anomeric 1-position and the 2- and 3- positions of the sugar was also explored. Indole was successfully glycosylated with a glucose subunit at the anomeric position (v) using the anhydrosugar (iv) and indoline was glycosylated with a glucose sugar derivative at the 3-position (viii) using the manno-epoxide (vi).
34
Commander, Paul Martin Brial. "An investigation of the regulation and synthesis of a novel quorum sensing controlled pigment from Erwinia carotovora." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620587.
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35
Kurniadi, Juliana [Verfasser], Martin [Akademischer Betreuer] Möller, and Alexander [Akademischer Betreuer] Böker. "In situ synthesis of pigments in keratin fibres / Juliana Kurniadi ; Martin Möller, Alexander Böker." Aachen : Universitätsbibliothek der RWTH Aachen, 2015. http://d-nb.info/1128156970/34.
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36
Russu, Sergio. "High-throughput synthesis and characterization of vanadium mixed metal oxide pigments using synchrotron radiation." Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/71830/.
Full textAbstract:
UNA range of inorganic vanadium mixed metal oxides, with potential applications as inorganic pigments, have been synthesised and characterised in terms of their crystal structure, and band gap energies using powder X-ray diffraction (PXD), synchrotron-based X-ray absorption fine structure (XAFS) spectroscopy, solid state UV-Visible and Raman spectroscopy, Scanning and Transmission electron microscopy (SEM and TEM). Vanadium mixed metal oxide BiMeVOX with Me = Mo, Cu and Fe, and calcium pyrovanadate with Me = Pb, Cd, Sr, doped systems, have been synthesised in sequential and high throughput array by peroxo sol-gel methods and calcined at 700°C in an oxygen atmosphere. Powder X-ray diffraction studies show the synthesised BiMoVOX (Bi1-x/3Mo1-xVxO4) to have a tetragonal crystal structure in the space group I 41/a, BiCuVOX and BiFeVOX (Bi2V1-xMexO5.5-γ) to have a tetragonal crystal structure in the space group I 4/mmm, and pyrovanadate ((Ca2-x,Mex)V2O7) to have triclinic in the space group P-1. PXD profiles have displayed phase transitions from monoclinic to tetragonal crystal phase together with peak positions shift, reflecting the changes in d-spacing and consequent volume cell growth by incorporation of the different ions into BiMeVOX; the calcium pyrovanadate kept their triclinic crystal structure. Raman and XAFS spectroscopy data analysis have shown isolated metal-oxygen tetrahedra for both vanadium and molybdenum cations in the BiMoVOX materials. Vanadium coordination in both the BiFeVOX and the BiCuVOX materials is more complex with three different cases: octahedral distorted, trigonal bipyramid and tetragonal ; these structure consists of alternating layers of [Bi2O2]2+ and [VO3.5□0.5]2-, where □ represents oxide ion vacancies. Calcium pyrovanadate materials display vanadium-oxygen polyhedra for a tetrameric chain comprising two edge-shared VO5 pyramids, and each also sharing a corner with a VO4 tetrahedron. UV-Visible spectroscopy of these materials reveals broad reflectance bands and a steep absorption edge, which is directly related to the band gap energy of the compound. By varying the doping levels on the vanadium and calcium site with different cations the colour of the compounds can be seen to visibly alter. This can be attributed to a modification in the band gap energies as direct result of the fine-tuning of the electronegativity difference between cations and anions, their overall contribution to the molecular orbitals of the materials, and the total concentration of oxygen vacancies. SEM and TEM analysis showed a more round particle shape for samples made by the peroxo sol-gel reaction compared to samples made by calcinations reaction in the BiMoVOX series.
37
Gayo, Griselda Xoana. "Fabricación de pigmentos cerámicos con criterios sustentables." Doctoral thesis, Universitat Jaume I, 2017. http://hdl.handle.net/10803/404047.
Full textAbstract:
Se aborda la fabricación de pigmentos cerámicos, empleando el método tradicional de síntesis, a partir de sistemas oxídicos estructuralmente simples y por incorporación de una mínima cantidad de cationes cromóforos como dopantes. Se ha enfocado el desarrollo de los pigmentos, a partir de las propiedades fisicoquímicas de los materiales cristalinos y la posible formación de soluciones sólidas coloreadas y pigmentos estructurales, con el fin de aplicarlos en esmaltes cerámicos. Para la caracterización y análisis de propiedades de los materiales se emplearon diversas técnicas de análisis.
Los resultados se detallan a partir del Capítulo 3, desarrollándose materiales con estructuras típicas de rutilo, willemita y de composición LnCrTeO6. En el Capítulo 6, se aborda la posibilidad de reutilizar un residuo rico en cromo, en la síntesis de pigmentos y en la coloración de matrices cerámicas, reduciendo el impacto ambiental.This thesis is focussed on the manufacture of ceramic pigments, using the traditional ceramic procedure of synthesis, departing from structurally simple oxidic systems and by incorporating a minimum amount of chromophore cations as dopants. This study is based on the physicochemical properties and crystalline structures of the materials. The development of the pigments has been established on the possible formation of colored solid solutions and structural phases, in order to apply them in ceramic enamels. Various techniques of analysis were used for the characterization and analysis of properties of the materials. The results obtained are detailed, starting from Chapter 3, with the development of materials with the typical structures of rutile, willemita and mixed oxides LnCrTeO6. In Chapter 6, the possibility of reusing a chromium-rich residue, both in the synthesis of pigments and in the coloring of ceramic matrices, is discussed, for its revaluation and reduction of environmental impact.
38
Howie, Bruce David. "Synthesis and evaluation of pigments with the potential to replace compounds based on 3,3'-Dichlorobenzidine." Thesis, Heriot-Watt University, 2003. http://hdl.handle.net/10399/433.
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39
Chughtai, Imran Bashir. "The influence of synthesis conditions on the surface character and application properties of azo pigments." Thesis, Heriot-Watt University, 1999. http://hdl.handle.net/10399/1156.
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40
Hepburn, James. "An investigation into the enhancement of fluorescence of disazo pigments by their synthesis in micellar solutions." Thesis, University of Strathclyde, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486456.
Full textAbstract:
The fluorescence of a series of commercially important yellow disazo pigments have been investigated with a view to enhancing fluorescence in the solid state. Solution absorption and fluorescence measurements in 1,2,4-trichloroben2;ene for some of the pigments was hampered by poor solubility. A comparison of the fluorescence intensities - normalised with respect to the amount of light absorbed - showed PY63 as being the most fluorescent in solution followed by PY12; PY14 and PY13. Fluorescence of the pigments in the solid state (as printed inks and aqueous dispersion~) showed that the relative intensities remained largely the same except that PY12 was found to be more fluorescent than PY63. The calculated absorption maxima by ZINDO/S and PPP-MO methods using the crystal structures showed good agreement with solution measurements. Comparison ofthe crystal structures of the pigments with fluorescence in the solid state showed that fluorescence correlates well with intermolecular stacking distances. It was also shown, however, that other distances, both intramolecular and interatomic, exhibit a similar trend and that the fluorescence intensities in the solid state may be incidental to, and not necessarily dependent on, the intermolecular stacking distances. It was observed that synthesis of the diarylides in micellar solutions of an amine surfactant, N,N'-dimethyldodecylamirie, brought about· an enhancement of fluorescence. of the pigments as inks printed on paper. This increase in fluorescence intensity was accompanied by an increase in crystallinity and particle size as evidenced -by powder x-ray diffraction, B.E.T. surface area and T.E.M. measurements. An investigation into the effect of pigment crystallinity on fluorescence by preparation of two model pigments, Pigments Yellow 12 and 14, at various stages of crystallinity, showed that even drastic changes in crystallinity had little effect on the fluorescence intensity. .It was found that particle size had much more of an influence on the fluort;::scence-.of the pigment. It was also found that the surfactant used was more effective at increasing fluorescence for PY12 than for PY14 and this was thought to be due to the different surface characteristics of the pigments as a consequence of their different crystal structures.
41
Alvarez, Mary Allison. "Pyridinium Bis-retinoids: Extraction, Synthesis, and Folate Coupling." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/8870.
Full textAbstract:
This thesis is divided into two parts.Part I describes the organic extraction, separation, and liquid chromatographic-mass spectrometric analysis of chromophores from human and bovine retinal pigment epithelium. Flurorophores in the retinal pigment epithelium have been implicated in age related macular degeneration. In addition, the synthesis and characterization of a number of bis-retinoid type compounds that may potentially be found in such extracts, or that may be used for insight into pyridinium bis-retinoid reactivity, was accomplished.Part II describes a study of pyridinium bis-retinoid-folic acid coupling with respect to linker type, linker length, and nature of the linkage. Folic acid has been used as a targeting compound for a variety of cancer types. Development of HPLC and UV-Vis conditions suitable for the analysis of this new type of macromolecule was performed.
42
Jin, Jiyang. "Synthesis of Novel Hydrogen-Bonding Unit for Organic Field-Effect Transistors." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1460047707.
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43
Sturtz, Benjamin Walden. "Synthesis and Structural Chemistry of Diamagnetic Dimeric Metal Phthalocyanines." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1496922051865658.
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44
Bat, Erhan. "Synthesis And Characterization Of Hyperbranched And Air Drying Fatty Acid Based Resins." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606270/index.pdf.
Full textAbstract:
There has been a considerable effort in the last years to decrease the amount of volatile organic compounds (VOCs) present in organic coatings. The risks to human health and environmental hazards associated with VOCs, governmental directives, and economic factors are the main driving forces behind this effort. One way of achieving less or no VOC containing coating systems is to produce low viscosity resins. Hyperbranched resins owing to their globular structure have low viscosities and are promising materials for decreasing the VOCs. In this research hyperbranched resins having properties close to alkyds were synthesized. Dipentaerythritol, which was used as the core was esterified with dimethylol propionic acid. The hyperbranched polyester was then esterified with the castor oil fatty acids (Castor FA). The hydroxyl group of the ricinoleic acid present in the castor FA was modified with different amounts of linseed oil fatty acids (Linseed FA) and benzoic acid.
The chemical characterization of the resins was achieved by FTIR spectroscopy and the thermal properties were determined by DSC. Then, the physical and the mechanical tests were carried out. The resins containing the Castor FA only and 32.5 % Linseed FA in addition to the Castor FA had 24 and 68 Persoz hardness, respectively. The viscosity of the resins decreased from 17.3 Pa
s to 5.8 Pa&
#61655
s as the amount of the Linseed FA was increased. The resins showed excellent adhesion, gloss, flexibility and formability.
45
Karakaya, Ceylan. "Synthesis Of Oil Based Hyperbranched Resins And Their Modification With Melamine Formaldehyde Resins." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606339/index.pdf.
Full textAbstract:
In this research hyperbranched resins containing fatty acid residues like alkyds were synthesized. Dipentaerythritol which has six hydroxyl groups was used as the core molecule, and it was transesterified with (i) castor oil, and (ii) a mixture of castor oil and linseed oil at 240°C in the presence of sodium hydroxide as catalyst. The resulting molecule, in either case, was then esterified with dimethylol propionic acid at 140°
C in the presence of p-toluene sulfonic acid as catalyst. Melamine-formaldehyde resin was synthesized to be used with the synthesized hyperbranched resins, and it was successfully modified by all hyperbranched resins at a ratio of 3:1. FTIR spectroscopy was used to characterize the hyperbranched resins and the thermal properties were determined by DSC. DSC showed that the hyperbranched resins decomposed between 315-345°
C. The viscosity of the resin that was synthesized by using only castor oil was 3.0 Pa.s and by using 50% linseed oil it was 1.0 Pa.s. When reacted with dimethylol propionic acid, the former&rsquo
s viscosity increased to 7.0 Pa.s, and the second&rsquo
s viscosity increased to 3.7 Pa.s. The hyperbranched resins showed excellent adhesion, gloss, flexibility, and formability. The mixture of hyperbranched resin plus melamine-formaldehyde resin samples had higher hardness values but lower gloss, adhesion and bending resistance values than the hyperbranched resins, and they had good impact and abrasion resistances.
46
ROSSIGNOL, NATHALIE. "Procedes d'extraction et de separation par membranes appliques a la production du pigment endo- et exocellulaire synthetise par la diatomee haslea ostrearia simonsen. Mise en oeuvre d'un photobioreacteur a membranes a fonctionnement continu." Nantes, 1999. http://www.theses.fr/1999NANT2095.
Full textAbstract:
L'etude s'inscrit dans le cadre de la valorisation de la diatomee marine haslea ostrearia. Celle-ci secrete un pigment bleu specifique (marennine) qui presente un interet en aquaculture (verdissement d'huitres) et dans le domaine bio-medical (cancerologie, cosmetologie). L'objectif est d'optimiser la production de marennine exocellulaire au sein d'un photobioreacteur associe a un procede a membrane adapte, tandis que la marennine endocellulaire est extraite par des techniques de cassage innovantes. L'etude comporte trois parties : la premiere concerne la separation des algues de leur milieu de culture. Des membranes organiques d'ultra- et de microfiltration de seuils de coupure, de materiaux et charges de surface differents sont etudiees. Les effets de l'adsorption (cinetique, equilibre) sont d'abord quantifies en utilisant l'alginate de sodium comme adsorbat modele. L'etude des parametres operatoires : pression, vitesse et concentration permet de degager des criteres de choix pour l'optimisation du photobioreacteur a membranes a fonctionnement continu. La deuxieme partie est relative a l'optimisation de la production de marennine par des cultures conduites en photobioreacteur a membranes. Avec une batterie de 3 a 10 photobioreacteurs fonctionnant en parallele, la teneur en nitrates ainsi que le taux de renouvellement du milieu reactionnel se sont averes etre les parametres essentiels favorisant la productivite en exometabolites. Sur des durees de 3 a 6 semaines avec soutirage continu, les productivites specifiques en marennine sont 2 a 4 fois superieures a celles d'un procede fonctionnant en batch. Ce type de reacteur a boucle de circulation externe est ensuite compare a deux autres systemes : le premier utilise un mode de culture ou les cellules sont immobilisees, le second presente une technologie plus rustique avec un potentiel de developpement en aquaculture, les membranes sont alors immergees dans le bioreacteur. Dans la derniere partie, differents procedes permettant l'extraction optimale du pigment endocellulaire sont mis en uvre. Trois techniques de cassage sont evaluees : broyage mecanique, ultrasons et desintegration haute pression (50-270 mpa) en continu.
47
Федоренко, Андрей Александрович. "Электрохимический синтез титана(III) сульфата в технологии производства титана(IV) оксида." Thesis, Таврический национальный университет им. В. И. Вернадского, 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/17223.
Full textAbstract:
Диссертация на соискание ученой степени кандидата технических наук по специальности 05.17.03 – техническая электрохимия. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2015 г.
Диссертация посвящена усовершенствованию сульфатной технологии производства пигментного TiO₂, путем внедрения технологии энергосберегающего электрохимического восстановления Fe³⁺ и TiO²⁺, с целью исключения из производства стадии обработки металлоломом железа и алюминием, как основных реагентов для получения атомарного водорода с целью восстановления ионов. Известные технологии имеют существенные недостатки, которые значительно снижают качество конечного продукта – накопление гидролизованного Fe³⁺ в пасте ГДТ, расход концентрированной серной кислоты на растворение металлолома железа и порошкообразного алюминия и связывание хромофоров Mn²⁺, Cu²⁺, Ni²⁺, железа в FeSO₄×7H₂O и др., наличие которых в растворах приводит к необратимым загрязнениям ГДТ и низкому выходу по току конечных продуктов. На основании системного анализа электрохимических, гальваномагнитных измерений и модельных расчетов доказан эстафетный механизм восстановления ионов H⁺ и TiO²⁺ в технологических растворах серной кислоты, который происходит при участии H⁺, Н⁰, Н¯, Н, H₂⁺ и др. ионов и их восстановленных форм в сжатом катодном двойном электрическом слое (ДЭС). Они принимают участие в трансляции электронов в плоскость скольжения Н₃О⁺ и TiO²⁺. Исследования электрохимических свойств электродных материалов, влияния магнитного поля на режимы электролиза и физико-химических особенностей технологических растворов, позволили устранить недостатки существующих технологических схем, за счет замены материалов электродов, выбора целесообразных режимов электролиза по плотности тока. Оптимальным режимом электрохимического восстановления [TiO(H₂O)₄]²⁺ является плотность тока ~ 5,0 А/дм², при которой достигается максимальный выход по току восстановителя. Выбор материалов для катодов и анодов сосредоточен на ndm элементах (n = 3 – 5 квантовые уровни), с заполнением электронами d – орбиталей от 20 до 80 %. Это связано с тем, что указанные элементы имеют незаполненные орбитали, поэтому могут участвовать, как кислоты, в комплексообразовании с гидрид–ионами. Этот процесс приводит к растворению водорода в подобных металлах и уменьшению в них удельного сопротивления. Установлено, что между удельным сопротивлением nd – металлов и количеством электронов, находящихся на d – орбиталях, существует функциональная связь. Чем больше заполнен d – подуровень, тем меньше удельное сопротивление, что положительно сказывается на перенапряжении выделения водорода. Но у металлов со 100 % заполнением электронами (Cu, Zn) отсутствует возможность присоединять водород и поэтому у них самое большое перенапряжение выделения водорода. В связи с этим, лучшими материалами для катодов являются сплавы nd – металлов и их сплавов, которые имеют склонность к растворению водорода. Подтверждением влияния растворенного водорода на перенапряжение выделения водорода, является ниобий и его сплавы, где имеет место прямо пропорциональная зависимость. Для осуществления эффективного электролиза разработаны и изготовлены электролизеры разных модификаций, в зависимости от состава и качества исходного сырья, что обеспечило возможность восстановления ионов Fe³⁺ и TiO²⁺ в технологических растворах и синтез Ti₂(SO₄)₃ , как в растворимой, так и кристаллической формах, с выходом по току <93 ± 3> %. На основании исследований оптических свойств соединений титана изготовлены оригинальные устройства – "Оптические анализаторы растворов" в двух модификациях с компьютерным интерфейсом и АСУ. Ввод оптического анализатора позволяет использовать синтез в автоматическом режиме и контролем восстановителя Ti₂(SO₄)₃ до 25–28%.Thesis for granting the Degree of Candidate of Technical sciences in specialty 05.17.03 – Technical Electrochemistry. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2015. The thesis work is devoted to the improvement of the sulfate production technology of the pigment TiO₂ via renewal of ions in the aqua of Fe³⁺ and TiO²⁺ not Fe, Al, but electrochemically, what excludes the chromophor accumulation in fluid converter mouth, thereby guarantees the end products high quality. However currently the overpressure of hydrogen separation and delay discharge theories are not general, that is why the search of cathode materials with the smallest hydrogen overpressure was performed. The solution was achieved via analysis of the double electric layer (DEL), where renewal of Fe³⁺ and TiO²⁺ occurs involving H⁺, Н⁰, Н¯, Н, H₂⁺ joins through relay mechanism. It is determined that ndm materials and their alloys, which have law electrical resistivity and are apt to hydrogen accumulation, they are stainless steel and niobium, are the best materials. Lorentz force is used during development of electrolyzer for convection diffusion increasing in the Ti₂(SO₄)₃ reductor synthesis. New optical Ti³⁺ control methods and creation of electrolysis computer control complex or ACS are offered during applying of synthesis on an automatic basis.
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Федоренко, Андрій Олександрович. "Електрохімічний синтез титану(III) сульфату у технології виробництва титану(IV) оксиду." Thesis, НТУ "ХПІ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/17220.
Full textAbstract:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.17.03 - технічна електрохімія. - Національний технічний
університет "Харківський політехнічний інститут", Харків, 2015.
Дисертація присвячена вдосконаленню сульфатної технології виробництва пігментного TiO₂ шляхом відновлення іонів в розчинах Fe³⁺ і TiO²⁺ не Fe, Al, а єлектрохімічно, що виключає накопиченя хромофорів в впасті ГДТ, тим самим гарантує високу якість готової продукції. Але, на цей час теорії перенапруги віділення водню та уповільненного розряду не є загальними, тому було виконано пошук матеріалів катоду з найменшою перенапругою водню. Вирішення досягнуто дослідженнями подвійного електричного шару (ПЕШ), де відновлення Fe³⁺ і TiO²⁺ відбувається за участю сполук: H⁺, Н⁰, Н¯, Н, H₂⁺ через естафетний механізм. Встановлено, що кращими матеріалами є ndm – метали та їх сплави, які мають низкий питомий опір і схилні до накопичення водю – ними стали нержавіюча сталь і ніобій. При розробці єлектролізерів для підвищення конвективної дифузії в синтезі відновника Ti₂(SO₄)₃ використана сила Лоренца. При використанні синтезу в автоматичному режимі запропоновано нові оптичні методи контролю Ti³⁺ та створення комплеку для керуванням електроліза компютером або АСУ.Thesis for granting the Degree of Candidate of Technical sciences in specialty 05.17.03 – Technical Electrochemistry. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2015. The thesis work is devoted to the improvement of the sulfate production technology of the pigment TiO₂ via renewal of ions in the aqua of Fe³⁺ and TiO²⁺ not Fe, Al, but electrochemically, what excludes the chromophor accumulation in fluid converter mouth, thereby guarantees the end products high quality. However currently the overpressure of hydrogen separation and delay discharge theories are not general, that is why the search of cathode materials with the smallest hydrogen overpressure was performed. The solution was achieved via analysis of the double electric layer (DEL), where renewal of Fe³⁺ and TiO²⁺ occurs involving H⁺, Н⁰, Н¯, Н, H₂⁺ joins through relay mechanism. It is determined that ndm materials and their alloys, which have law electrical resistivity and are apt to hydrogen accumulation, they are stainless steel and niobium, are the best materials. Lorentz force is used during development of electrolyzer for convection diffusion increasing in the Ti₂(SO₄)₃ reductor synthesis. New optical Ti³⁺ control methods and creation of electrolysis computer control complex or ACS are offered during applying of synthesis on an automatic basis.
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Chi-WeiLee and 李其蔚. "A Study on the Preparation of Pearlescent Pigment from Metal Oxide Coated Synthetic Mica." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/tg49fa.
Full textAbstract:
碩士國立成功大學
資源工程學系
104
Pearlescent pigments generally refers to mica flakes coated with one or more layers of high refractive index metal oxide films, such as TiO2 and Fe2O3, so that’s presenting a pearl luster effect under the irradiation of light. Synthetic mica has the characteristics of good transparency, smooth surface, less cracks, reflecting strong, good gloss, which replace the natural mica pearlescent pigment used as the base material. In this study, pearlescent pigments were prepared by the liquid chemical deposition method in the presence of titanyl sulfate and ferric chloride as the titanium source and iron source and fluorphlogopite as the substrate to be coated with TiO2 and Fe2O3. The influence of hydrolysis condition and dosage on the chroma and hue were measured using sphere spectrophotometer. The coating state on the surface as examined by SEM. The chemical composition and crystal phase of coated components were analyzed by XRF and XRD. According to the results of experiments, the following conclusions are obtained: 1. The optimum pH value and temperature for TiO2 coating on mica are: pH=0, 95℃, calcined at 750℃ for 2hrs. The best chroma of the products obtained is the best. 2. For Fe2O3, at pH=3, it is able to obtain a dense and smooth coated layer.
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Chyau, Jyh-Yuan, and 喬致源. "The Study on The Stability of Retouching Material: The Influence between Titanium White Pigment and The Vehicles of Synthetic Resin." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/hbpf78.
Full textAbstract:
碩士國立臺南藝術大學
博物館學與古物維護研究所
102
The study is researching about the influence of titanium white pigment in the vehicles for retouching materials. The overall plan will be conducted in progress by the references research, material analysis as well as the aging experiments. The samples, which are made from the handmade titanium white pigment in retouching materials, divide into three varied proportions: 10％, 20％ and 30％ respectively. Subsequently, each sample is added with three different types of vehicles of synthetic resin: Paraloid® B72、Laropal® A81 and MSA gel®. And further, the experiments is tried to test and compare with manual and commercial retouching color of titanium white in the effect of weathering. The result is illustrated the titanium white pigment has the both effects of photo-protection and photocatalysis in the vehicles of synthetic resin, Besides, the stability degree of vehicles and the proton of the titanium white pigment play the important role in these two reactions. Furthermore, the vehicle stability is higher the photocatalysis is less likely to appeal obviously and vice versa. The appropriate recipe of titanium white pigment content is 20% that has the best effectivity of photo-protection for vehicle; however, the photocatalysis may increase while its amount has more than 30%. In addition to, the commercial retouching color will take place deterioration of chemical structure and discolor in the aging, but the appearance and optics-property are still stability.