Tesi: "Dyes and dyeing Chemistry"

1

Matthews, Rosalyn D. "Transformation and decolorization of reactive phthalocyanine". Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04062004-164728/unrestricted/matthews%5Frosalyn%5Fd%5F200312%5Fphd.pdf.

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Thesis (Ph. D.)--School of Civil and Environmental Engineering, Georgia Institute of Technology, 2004. Directed by Spyros G. Pavlostathis.
Vita. Includes bibliographical references (leaves 381-393).

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2

Gilmore, Laurie Ann. "Chlorination of synthetic dyes and synthetic brighteners". Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/20794.

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3

Beydilli, Mumtaz Inan. "Reductive biotransformation and decolorization of reactive azo dyes". Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/21451.

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4

Carswell, Stewart. "Microanalysis of dyes from textiles". Thesis, Queensland University of Technology, 1991. https://eprints.qut.edu.au/35972/1/35972_Carswell_1991.pdf.

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The discrimination and/or matching of dye extracts is an important aspect of forensic investigations involving textile samples. The aim of this work was to study the use of Fourier transform infrared spectrometry and diffuse reflectance to obtain IR spectra of dye samples, and the subsequent analysis of these spectra using library searching and principle component analysis. The work in this thesis has demonstrated the development of a simple method for obtaining DRIFT spectra of dye samples. Library searching and principle component analysis were used to distinguish between many types of dye samples, including extracts that were not distinguished using TLC.

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5

Mousa, Souad Abd. "Photochemistry of β-carbolines and azine dyes in solution and colloidal systems". Thesis, Swansea University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678433.

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6

Lee, Young H. "Reductive biotransformation and decolorization of reactive anthraquinone dyes". Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04062004-164708/unrestricted/lee%5Fyoung%5Fh%5F200312%5Fphd.pdf.

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Abstract (sommario):

Thesis (Ph. D.)--School of Electrical and Computer Engineering, Georgia Institute of Technology, 2004. Directed by Spyros G. Pavlostathis.
Vita. Includes bibliographical references (leaves 332-345).

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7

Park, Jong Seung. "Studies on inclusion complexes of cyclodextrin and dyes I. Synthesis and properties of dye rotaxanes, II. Formation of anisotropic supremolecules /". Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-08262005-092849/.

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Thesis (Ph. D.)--Textile and Fiber Engineering, Georgia Institute of Technology, 2006.
Srinivasarao, Mohan, Committee Chair ; Bunz, Uwe, Committee Co-Chair ; Griffin, Anselm, Committee Member ; Tolbert, Laren, Committee Member ; Park, Jung, Committee Member ; Beckham, Haskell, Committee Member. Includes bibliographical references.

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8

Schiller, Robert Lindsay. "Kinetic and equilibrium studies of some dye-cyclodextrin inclusion complexes /". Title page, contents and abstract only, 1986. http://web4.library.adelaide.edu.au/theses/09PH/09phs334.pdf.

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9

Trujillo, Rebollo Andres. "ROLE OF BRILLIANT GREEN ON THE DETECTION AND SEPARATION OF NON-CHROMOPHORIC ANALYTES BY REVERSED-PHASE LIQUID CHROMATOGRAPHY (DIMERIZATION)". Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275434.

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10

West, Lee Charles. "A study of bibracchial lariat ether complexes and linked cyclodextrin dimer complexes". Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phw5182.pdf.

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Includes errata attached to first leaf. Includes bibliographical references. The complexation of a range of monovalent and divalent metal ions by the bibracchial lariat ethers has been investigated. Also investigates the complexation of metal ions and the anionic azo dye Brilliant Yellow by the diazacrown linked cyclodextrin dimers.

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11

Rushing, Charles W. Rushing Charles W. "Part A, Indoaniline dye formation ; Part B, Chlorite redox chemistry /". free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9999311.

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12

Yang, Hanbae. "Zero-Valent Iron Decolorization of the Anthraquinone Dye Reactive Blue 4 and Biodegradation Assessment of its Decolorization Products". Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6920.

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Anthraquinone dyes constitute the second largest class of textile dyes, and are used extensively in the textile industry. A high fraction of the initial reactive dye mass used in the dyeing process remains in the spent dyebath. Reactive dyes are not readily removed by typical wastewater treatment processes and the high salt concentration typical of reactive dyeing further complicates the management of spent reactive dyebaths. Investigation of the reductive transformation of reactive anthraquinone dyes and their decolorization products has been very limited. Additionally, very limited research has been conducted on the decolorization of spent reactive dyebaths. Research was conducted to investigate the key operational parameters of batch and continuous-flow ZVI decolorization of a reactive anthraquinone dye, Reactive Blue 4 (RB4), under anoxic conditions, as well as the potential for the biodegradation of its decolorization products in a halophilic culture under aerobic conditions. The effect of two operational parameters, such as mixing intensity and initial dye concentration, on the ZVI batch decolorization kinetics indicates that ZVI decolorization of RB4 is a surface-catalyzed, mass transfer-limited process. The high salt and base concentrations enhanced the rate of RB4 decolorization. Based on parameters such as porosity, hydraulic conductivity, pore water velocity, and dispersion coefficient, non-ideal transport characteristics were observed in a continuous-flow ZVI column. The results of a long-term continuous-flow ZVI decolorization kinetics demonstrated that continuous-flow ZVI decolorization is feasible. However, column porosity losses and a shift of reaction kinetics occur in long-term column operation. ZVI decolorization of RB4 was successfully described with a pseudo first-order or a site saturation model. Lastly, the RB4 decolorization products generated by ZVI treatment had no inhibitory effect on the halophilic culture. However, biodegradation and/or mineralization of RB4 decolorization products was not observed after a long-term incubation of the culture. This research demonstrated the feasibility of ZVI decolorization of reactive anthraquinone dyes, which will help in the development of a continuous-flow, dyebath decolorization process and the possible reuse of the renovated dyebath in the dyeing operation. Such a system could lead to substantial reduction of water usage, as well as a decrease of salt and dye discharges.

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13

Park, Jong Seung. "Studies on Inclusion Complexes of Cyclodextrin and Dyes; I.Synthesis and Properties of Dye Rotaxanes, II. Formation of Anisotropic Supremolecules". Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7482.

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Supramolecular chemistry covers intermolecular interactions where non-covalent bonds are involved, and many of them are based on host-guest interactions. Cyclodextrins (CDs) are cyclic oligosaccharides consisting of 6-, 7- or 8-glucose units, which are called alpha-, beta- or gamma-CDs, respectively. They have hydrophobic interior and hydrophilic exterior, and are widely being used as hosts for various organic molecules. The formation of CD inclusion complexes with a variety of dyes has continuously drawn our interests, since CDs are readily available and have ability to include dye molecules altering their properties. The present thesis covers the study of inclusion complexes of CDs and chromophore dyes, largely in two ways; rotaxane and pseudorotaxane. The stable rotaxane structure is achieved with the synthesis of dye rotaxane. The introduction of CD ring around azo chromophore provides a simple way to improve the solubility and stability of azo dye. We have shown that by incorporating proper compounds as a coupler, azo dye rotaxanes can be used as pH indicators and metal ion sensors. We have described the synthesis of novel acetylene dye rotaxane using the Pd-catalyzed reaction of Heck-Cassar-Sonogashira-Hagihara type. Its fluorescence properties in the solid state as well as in solutions are examined and compared with those of free dye. Free dye, which has tetra-carboxylic groups, is found to be highly sensitive to various metal ions, exhibiting high Stern-Volmer constants, K(SV). On the contrary, acetylene dye rotaxane exhibits much less quenching against various quenchers. The appearance of fluorescent anisotropic structure has been observed by the formation of inclusion complex between acetylene dye and gamma-CD. Its structural nature is studied by various techniques, including fluorescence, fluorescence anisotropy, wide angle X-ray scattering (WAXD) and differential scanning calorimetry (DSC) measurements. Methyl orange, an acid azo dye, forms a dimeric inclusion complex with gamma-CD, resulting in the formation stable anisotropic aggregates. Several other azo dyes are found to form anisotropic supramolecule in the presence of gamma-CD, and their structural characteristic has been discussed in terms of the number and position of solubilizing groups.

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14

Mothibedi, Kediemetse (Kedimetse). "A study of electrospun nanofibers and diatomaceous earth materials for the extraction of alkaloids, flavonoids and aromatic amines in various matrices". Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1003052.

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The thesis explored the use of different sorbent materials in solid phase extraction method development. The methods included the use of the polymeric Agilent Bond Elut Plexa solid phase extraction and electrospun polymer-silica composite sorbents for clean-up and preconcentration. Sample clean-up for alkaloids (hydrastine and berberine) in goldenseal, Hydrastis canadensis and flavonoids (quercetin, kaempferol and isorhamnetin) in Ginkgo biloba was achieved using Bond Elut Plexa SPE sorbent. Clean-up of flavonoids in Ginkgo biloba was also achieved using electrospun polymer-silica composite (polystyrene-silica, polyacrylonitrile-silica and nylon 6-silica) sorbents. All analysis of flavonoids and alkaloids was carried out using an Agilent 1200 Series HPLC coupled with a diode array detector. Good peak separation was achieved in less than 6 min employing an Agilent ZORBAX Eclipse Plus C18 column (4.6 x 75 mm, 3.5 μm) at 35⁰C. The mobile phases employed were 0.1% phosphoric acid/methanol gradient and 0.5% phosphoric acid/methanol (40:60) for alkaloids and flavonoids respectively. The calibration curves exhibited linearity up to 120 μg mL⁻¹ with correlation coefficients of more than 0.9980. The recoveries ranged from 73-109% with relative standard deviation of less than 5% for all analytes. Agilent Chem Elut supported liquid extraction was employed for the development of a sample preparation method for the determination of 24 banned aromatic amines from azo dyes in textile following the EU standard method EN 14362-1:2003 (E) and the Chinese standard method GB/T 17592-2006. The supported liquid extraction was effective in the extraction of the aromatic amines from textile (cotton, wool and polyester/cotton [80%:20%]). Most of the recoveries obtained were conforming to the minimum requirements set in the EN 14362-1:2003 (E) standard method and the relative standard deviations were less than 15%. Good peak separation was obtained within 70 min run time using the Agilent Zorbax SB-Phenyl column (4.6 mm x 250 mm, 5-micron) or the Agilent DB-35 MS (J & W) (30 m x 0.25 mm, 0.25 μm film thickness. It was demonstrated that the polymeric Agilent Bond Elut Plexa, electrospun nanofibers and diatomaceous earth were effective in extraction of alkaloids, flavonoids and aromatic amines in different matrices. The developed methods were simple, rapid and reproducible.

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15

Sanyova, Jana. "Contribution à l'étude de la structure et des propriétés des laques de garance". Doctoral thesis, Universite Libre de Bruxelles, 2001. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211674.

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Les laques de garance, les pigments artistiques dont les procédés de fabrication étaient souvent des secrets jalousement gardés, ont depuis longtemps éveillé l'intérêt des chimistes. Le premier mode opératoire de laque de garance décrit scientifiquement est dû à Marggrave en 1754, chimiste allemand célèbre surtout pour la découverte du sucre de betterave. L'élucidation de la structure chimique de l'alizarine par Graebe en 1868 est une des étapes fondatrices de la chimie organique. Il a ensuite vite été reconnu que, dans les laques, l'alizarine se trouve sous forme de complexes d'aluminium. Plusieurs structures ont été proposées dans la littérature pour les complexes d'alizarine et d'aluminium. Le site de complexation de l'aluminium y est constitué soit par les fonctions carbonyle en C-9 et phénolate en C-1 (site céto-phénolate), soit par les deux fonctions phénolates en C-1 et C-2 (site diphénolate).

Nos résultats montrent que, au moins en solution aqueuse diluée et acide, le site de complexation est le céto-phénolate et la stoechiométrie 1:1. En solution plus concentrée et neutre ou légèrement basique, il peut également se former des complexes de stoechiométrie 1:2, dont la couleur est par ailleurs pratiquement identique à celle des complexes de stoechiométrie 1:1. Quand les réactifs sont mis en présence en rapport stoechiométrique et neutralisés par NaOH (aluminium:alizarine:NaOH 1:2:5), les complexes 1:2 ainsi formés peuvent même polymériser en formant entre eux des liaisons Al-O-Al. Cependant, dans la pratique de la préparation des laques, aujourd'hui comme dans le passé, l'aluminium est présent en large excès par rapport à l'alizarine. Dans ces conditions, les complexes, au lieu de polymériser, s'adsorbent à la surface des grains d'alumine formés par l'aluminium en excès. Nous n'avons trouvé aucune indication de la formation de complexes 2:4. Il est probable que de tels complexes ne sont, comme les gels que nous avons obtenus dans certaines conditions, que des cas particuliers, non représentatifs de la structure des laques réelles. La stoechiométrie des complexes et leur état physique ne seraient que des caractéristiques secondaires. Dans le cas des laques utilisées comme pigments, il s'agirait de complexes 1:2 et probablement aussi 1:1, adsorbés sur les grains d'alumine via des liaisons Al-O-Al.

La compétition entre ions H+ et Al3+ pour les phénolates est à la base de la libération des molécules d'alizarine dans les méthodes classiques d'extraction des colorants des laques par un acide pour leur analyse par HPLC. Nos résultats montrent que la concentration en ions H+ nécessaire pour libérer les colorants est proportionnelle à la concentration en ions Al3+ en solution. Dans la pratique, le pH nécessaire est très bas, ce qui a pour conséquence négative d'hydrolyser certaines des molécules colorantes constitutives des laques. L'addition d'ions F- permet de pallier ce problème. En formant des complexes avec les ions Al3+, les ions F- relèvent assez le pH minimum d'extraction pour éviter l'hydrolyse des colorants moins stables (glycosides, pseudopurpurine.), et donnent de plus des rendements d'extraction souvent meilleurs que ceux obtenus avec les autres acides (HCl, H2SO4, TFA). L'addition d'ions Li+, qui par leur petite taille peuvent plus facilement se glisser à l'intérieur des complexes, et d'agents chélatants tels que le DFOM, qui contribuent à capter les ions Al3+, améliore encore l'extraction des colorants.

Des propriétés telles la granulométrie, la porosité et l'hygroscopicité des laques sont celles de l'alumine qui constitue leur substrat. Les analyses de différentes laques d'extraits de Rubiacées montrent :

- la présence fréquente de pseudopurpurine et de glycosides; ces colorants ne sont détectés qu'après extraction à pH ~ 2 (extraction par HF), parce qu'à pH plus acide ils sont hydrolysés.

- la teneur en différents colorants est influencée non seulement par l'espèce de plante, mais aussi par le mode de préparation des laques.

La couleur apparente et les spectres dans le visible des chélates aluminium-anthraquinone sont bien distincts de ceux des mêmes colorants en l'absence d'aluminium. Les paramètres L*a*b* et leur équivalent en coordonnées cylindriques L*c*h*, calculés à partir des spectres de réflectance, permettent de caractériser la couleur des objets, telle qu'elle serait perçue sous une lumière de spectre donné et par un "observateur de référence". On constate que la teinte des laques dépend surtout de la nature des colorants présents sous forme de chélates d'aluminium. La saturation dépend surtout du rapport aluminium/colorant, et augmente avec celui-ci, ce qu'on peut attribuer à un meilleur rendement de la formation de complexes quand l'aluminium est présent en plus large excès.

Pour mieux comprendre les facteurs affectant la permanence des laques, une approche est de soumettre des laques préparées dans des conditions connues à des tests de vieillissement accéléré par une lampe à arc de xénon. Une première étude de ce type menée sur des laques sous forme de poudres fixées sur des filtres montre que dans les laques fort concentrées au départ, la majorité des colorants peut être dégradée sans que la couleur perceptible ait fort changé. A l'observation au microscope, on constate que les grains les plus petits ont tendance à décolorer plus vite. Cependant globalement le principal facteur affectant l'évolution de la couleur est la concentration en colorants. Il semble donc que les complexes de colorants adsorbés à la surface de la porosité interne des grains d'alumine soient protégés de la lumière par les complexes adsorbés dans les couches plus externes, et que cette protection soit proportionnelle à la concentration en colorant. La photodégradation est probablement oxydative. Elle est d'ailleurs beaucoup plus lente pour les teintures d'alizarine sur laine, grâce probablement aux propriétés réductrices de la laine. Il faut donc s'attendre à ce que, dans les polychromies, la présence des liants ralentisse le vieillissement en limitant la diffusion de l'oxygène, ce qui n'était pas le cas dans nos laques poreuses vieillies au contact de l'air. C'est là un des aspects que la suite des études de vieillissement accéléré devrait tenter d'éclaircir.

Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished

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16

Morris, Kathryn Fiona. "The dyeing of cotton with multi-functional reactive dyes". Thesis, University of Leeds, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418783.

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17

Li, Shiqi. "On-line dye analysis for carpet dyeing processes". Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/8596.

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18

Gore, Darren W. "Electrochemical reduction of vat and sulfur dyes : introducing a recyclable system". Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/8530.

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19

Mmelesi, Olga Kelebogile. "Synthesis and characterization of pine cone carbon supported iron oxide catalyst for dye and phenol degradation". Thesis, Vaal University of Technology, 2017. http://hdl.handle.net/10352/418.

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M. Tech. (Department of Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology
Fenton oxidation is classified into two processes, homogeneous and heterogeneous. Homogeneous Fenton oxidation process, have been shown to be efficient in the degradation of organic pollutants. However, it was shown to have limitations which can be addressed by the heterogeneous Fenton oxidation. Despite the high efficiency of the heterogeneous Fenton oxidation process in the degradation of recalcitrant organic pollutants, the currents synthesis trends of the heterogeneous Fenton catalyst have been proven to be time and energy constraining, since it involves the multi-step were the activated carbon have to be prepared first then co-precipitate the iron oxide on the activated carbon. However, as much as the heterogeneous Fenton catalyst has been proven to have high catalytic activity towards degradation of organic pollutants, these catalysts have some limitations, such limitations include metal ions being leached from the catalyst support into the treated water causing catalyst deactivation and a secondary pollution to the treated water. In this thesis, these catalysts have been applied in the degradation of recalcitrant organic pollutants such as methylene blue and phenols. This study focuses on the single step synthesis of iron oxide nanoparticles supported on activated carbon, were carbonaceous material is impregnated with iron salt then pyrolysed via microwave heating. Microwave power and the amount of iron salt were optimized. The prepared activated carbon-iron oxide composites were applied to the degradation of 2-nitrophenol (2-NP) and methylene blue (MB). Methylene blue was used as a model compound due to the fact that it is easier to monitor the degradation process with UV-Vis as compared to 2-nitrophenol . 2-nitrophenol the additional step for the adjustment of pH is required since nitrophenols are colorless in color at lower pH. The characterization showed that the microwave power and the amount of the iron precursor have an influence on the porosity and surface functional groups of the activated carbon. Further it was vi observed that microwave power and iron precursor influnces the amount of iron oxide formed on the surface of the support. It was also observed that the activated carbon-iron oxide composite have the catalytic effects on the Fenton oxidation process of MB and 2-NP. The parameters such as H2O2, pH, catalyst dose, initial concentration, temperature affect the degradation of both MB and 2-NP. Kinetics studies showed that Fenton is a surface driven reaction since the results fitted the pseudo first order model. The thermodynamics parameters also showed that the reaction is endothermic, spontaneous and is randomized. This implies that the reaction of the degradation of MB and 2-NP is feasible and the catalysts prepared have high catalytic activity. MB and 2-NP were degraded to smaller organic molecules (carboxylic acids). The stability of the catalyst observed to decrease as the number of cycles increased, this is due to the leaching of iron ions from the support material. Hence it was concluded that the activated carbon-iron oxide composite was successfully synthesized and had the high catalytic activity for the degradation of MB and 2-NP.

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20

Boonroeng, Supannee. "An analysis system for dye delivery on continuous dyeing ranges". Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/10175.

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21

Leung, Yue Hin. "An experimental study of dyeing : polyester and cotton /". View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CBME%202009%20LEUNG.

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22

Stephen, Rosary Ann. "Enzymatic formation of colorants". Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Fall%20Theses/Stephen_Rosary_14.pdf.

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23

Scharfbillig, Ilse Margarete. "Preliminary studies into the development of new procedures for the covalent attachment of dyes to wool fibre /". Title page, contents, acknowledgements and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phs311.pdf.

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24

Alves, Maria Helena Traquete Carvalho Botelho da Palma. "Tinturaria tradicional - uma abordagem em contexto escolar". Master's thesis, Universidade de Évora, 2012. http://hdl.handle.net/10174/14668.

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No ensino de Química fala-se na “abordagem do quotidiano” e pretende-se “mostrar” ao aluno fenómenos químicos com que ele possa estar familiarizado. Nesta perspetiva, e considerando que o Programa de Química do 10º ano do Ensino Secundário contempla o estudo do espetro eletromagnético, da ligação covalente e uma abordagem simples sobre os compostos orgânicos, propõem-se neste trabalho um conjunto de atividades no âmbito da tinturaria tradicional que permitem exemplificar a importância que estes conceitos assumem no dia a dia e que constituem uma maneira diferente de abordar estes temas no ensino de Química. Os alunos efetuaram tingimento de fibra de lã com corantes naturais: índigo com e sem a presença de redutor em meio básico; garança, casca de cebola e pau campeche utilizando como mordentes alúmen e sulfato de cobre em concentrações diferentes e recorrendo a métodos de tingimento diferentes. Traçaram-se também os espetros de absorção molecular das soluções de mordentes e das soluções padrão de alguns dos cromóforos constituintes dos corantes utilizados, com e sem mordente, que foram relacionados com a cor da solução e, por fim, com a cor da lã tingida e o modo como se estabelece a ligação fibra de lã-mordente-cromóforo. O impacto deste trabalho no processo de aprendizagem foi avaliado através de observação de aula, relatório, teste teórico-prático, e questionário fornecidos aos alunos; ABSTRACT: An everyday life approach is promoted in Chemistry teaching and students are expected to be confronted with chemical phenomena that are familiar to them in their daily lives. Within this scope and taking into consideration that the 10th Form Chemistry Curriculum of Secondary Education includes studying the electromagnetic spectrum, covalent bonding and a simple focus on organic compounds, a set of activities on traditional dyeing are used to exemplify the importance of these concepts in daily life, which constitutes a different way of approaching these subjects in Chemical teaching. The students applied natural dyes to wool fibre: indigo (both with and without the presence of reducing agents), madder (Rubia tinctorum L.), onion, yellow skin, (Allium cepa L.) and campeachy wood (Haematoxylum campechianum L.), using alum and copper sulfate as a mordant in different concentrations and in different dyeing processes. Molecular absorption spectra were also drawn both of mordant and pattern solutions of some chromophores of these dyes (with and without mordant), which were then compared both with the colour of the solution and with the colour of the dyed wool and eventually with the way how the wool fibre-mordant-chromophore bond is set. The impact of the task on the students’ learning process was assessed using direct observation, an activity report, a quiz and a theoretical and practical test.

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25

Koppetsch, Karsten J. "Photodegradation of organic photochromic dyes incorporated in ormosil matrices". Link to electronic thesis, 2000. http://www.wpi.edu/Pubs/ETD/Available/etd-0509100-092225/.

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26

Bakhshaee, Mojgan. "Effect of surface charge on acid dyeing of nylon 6,6". Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/9977.

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27

Berry, Lee J. "Evaluation of novel plasticizers as carriers in dyeing aramid fabrics". Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/9978.

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28

Dayla, Mackraj. "Environmentally friendly dyeing and finishing". Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020776.

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The textile industry in South Africa is a significant contributor to the chemical load that public wastewater treatment plants have to process, and the discharge of toxic substances, especially to the aquatic environment. In order to address this issue at factory level, the processes at a textile plant, JMV Textiles were chosen for investigation into the possibilities of minimization of discharges of harmful substances into the environment. The study followed the principles of cleaner production, and the processes that were investigated and revised were: The conventional peroxide bleaching process employed a peroxide stabilizer that did not biodegrade easily. The bleaching process was changed, so that the prevailing conditions in the fabric and dyebath facilitated bleaching without the addition of peroxide stabilizer, and also reduced the alkali and energy requirements. Polyester‐viscose fabric was pretreated by bleaching with hydrogen peroxide, which seemed to be unnecessarily rigorous, because polyester and viscose, unlike natural fibres, are relatively clean and have good whiteness in comparison with natural fibres. The proposed alternate pretreatment was a scour with detergent and alkali. The pretreatment for all polyester‐cotton fabrics was also a hydrogen peroxide bleach. Due to the ability of medium and dark shades to mask the natural tint of cotton fibres, a simpler alternate pretreatment, consisting of an alkaline scour with sequestering agent, was trialled. An unacceptable proportion of the dyeings on polyester was rejected for dye‐stains and dye‐marks. A possible solution exploited the properties of using the finishing auxiliary chemical to alleviate dye‐stains and dye‐marks during the dyeing stage, instead of using the chemical after dyeing. The highly toxic carrier that was used to facilitate level dyeing of polyester fibres that had unacceptable variation in their dyeing properties, was replaced by a less toxic carrier. The formulation for dyeing polyester was simplified to eliminate the auxiliary chemicals that were not essential to the dyeing process. Pale reactive dyed shades on cellulose and polyester‐cellulose were washed off only with hot water instead of detergent. The revised procedures consequential to the study, offered significant environmental benefits by reducing the concentration and volume of effluent produced, substituting a highly toxic carrier with a less toxic one and saving energy and water. Implementation of the suggested changes also offered financial benefits. The management of the factory, however, accepted and implemented some changes, but wanted further investigations for others and a phased approach to the other suggested changes.

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29

Gupta, Murari Lal. "Development of commercial, sustainable processes for dyeing generic, unmodified polypropylene fiber". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26643.

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Thesis (Ph.D)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Cook, Fred; Committee Member: Beckham, Haskell; Committee Member: Bottomley, Lawrence; Committee Member: Carr, Wallace; Committee Member: Etters, Nolan. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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30

Rashid, Ahtisham. "Polyfunctional Reactive Dyes and Their Utility In High Temperature and Garment Dyeing". Thesis, University of Manchester, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525186.

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31

Luo, Xujun. "Synthesis of reactive disperse dyes for dyeing natural fabrics in supercritical CO2". Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/18859/.

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Over the course of time, the dyeing industry has become one of the greater polluters of water worldwide. The sheer volume of water and the high concentration of additives used in textile colouration are staggering, which have already caused unrepairable damage to environment and continue to directly impact on the sustainability of textile colouration industry. “Supercritical CO2 dyeing” uses supercritical CO2 as the dyeing medium, enabling the reduction and even elimination of the creation of textile colouration wastewater. Supercritical carbon dioxide (scCO2) has a low critical point and is non-flammable. It can be recycled, providing a promising environmentally friendly substitute for aqueous media. Reactive disperse dyes that have both reactivity towards natural fabrics and high solubility in scCO2 would offer great promise for colouring natural fabrics. In this study, the isocyanate group, as a reactive group, was introduced to disperse dyes to create reactive disperse dyes suitable for supercritical dyeing. Thus, a series of reactive disperse dyes, containing both isocyanate groups and alkyl groups were successfully synthesised. Dyeing experiments under different dyeing conditions were performed to establish the optimal dyeing conditions for these synthesised dyes. A new synthesis route was developed to create an azo-based disperse reactive dye containing the vinyl sulphonyl reactive group, which was used to dye natural fibres using scCO2 as the dyeing medium. Using relatively moderate, optimal conditions in the scCO2 dyeing processes, uniform dyeing with high colour strength and fastness properties that were similar to those from conventional aqueous dyeing were achieved on natural fabrics that were dyed with the synthesised dyes. Furthermore, there are opportunities to modify a wide range of disperse dyes following this synthesis route.

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32

Lee, Kwok Choi. "Fixed bed modeling for the sorption of acid dyes on carbon /". View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?CENG%202002%20LEE.

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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2002.
Includes bibliographical references (leaves 185-202). Also available in electronic version. Access restricted to campus users.

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33

Bond, Tracy. "Control of color in dyed paper". Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28366.

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This paper will examine and evaluate via computer simulations different methods, both adaptive and non-adaptive, for the feedback control of the color of dyed paper. The objectives are to maintain the paper color at a desired setpoint despite disturbances such as addition of recycled dyed paper (i.e. broke), and to perform color changes as smoothly as possible. The dynamics of a three dye system are multivariable and nonlinear with a significant transport time delay: thus the incentive for adaptive control. Several predictor-based and Dahlin controllers with gain scheduling are designed, tested in simulation, and compared. Adaptive versions using parameters identified with Recursive Least Squares (RLS) are also tested. For practical applications, the non-adaptive Dahlin algorithm with gain scheduling is shown to offer the best performance, together with relative ease of use.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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34

McFarland, Elizabeth Gramling. "A new method for determining diffusion and convection mass transfer coefficients in the dyeing of textile materials". Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/12416.

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35

Tsakanikas, Panayotis Dimitrios Sokrates. "A SPECTROSCOPIC STUDY OF RHODAMINE-6G: DETECTION OF NONABSORBING ANALYTES IN REVERSE-PHASE CHROMATOGRAPHY WITH THE AID OF RHODAMINE-6G (FLUORESCENCE, ABSORPTION)". Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/291292.

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36

Golding, G. M. "Micro analysis of dyes from transferred fibres". Thesis, Queensland University of Technology, 1987. https://eprints.qut.edu.au/35954/1/35954_Golding_1987.pdf.

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Thin Layer Chromatography (TLC) has been used for many years for the characterisation of dyes extracted from textile materials. It has recently been applied to the comparison of dyes extracted from short fibre monofilaments which may have been transferred during a criminal contact. The forensic methods for plate preparation and development are generally empirical, and interpretation of the chromatogram commonly based on subjective visual observations. The aim of this work was to examine systematically the Thin Layer Chromatographic separation of small quantities of dye to improve the quality and quantity of comparative information available to the analyst. Among other aspects the work in this thesis has shown: 1) Plate activity, normally considered a problem, can be used to advantage to manipulate the Rf of a dye into a more suitable region of the TLC plate, thus obviating the need to seek solvent systems of different polarity. 2) A method for the selection of paired solvent systems for disperse, acid and reactive dyes is proposed, tested, and successfully applied using a wide range of solvent systems. 3) A novel approach using a Camag TLC/HPTLC Scanner to examine objectively TLC information is described and is shown to be superior to visual examination methods.

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37

Benedict, Jason Brown. "Dyeing crystals : 19th century phenomenology to 21st century technology /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/8636.

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38

Patel, Dinesh G. "Organic dyes for photoswitching and photovoltaic applications /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/8537.

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39

Camp, Sharon Kay Ritchie. "The HPLC separation and electrochemical detection of azo dyes and their degradation products". Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/27686.

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40

McAllister, Liam John. "Modification of natural dyes for superior dyeing capability, high fastness and wide colour gamut". Thesis, University of Leeds, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590472.

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The issue of sustainability has pervaded many areas of technology in recent years, in response to concerns over the possible impact of such technologies on the environment. One such technology is the textile industry, which is at present heavily dependent upon the supply of petrochemicals. The petrochemical industry will at some point in the immediate future, have to tackle not only the price of oil but also the gradual decrease in its availability. The development of technologies that offer genuine solutions to these problems are of crucial importance. Azo dyes account for a major percentage of the dyes currently in use, with anthracene-9,IO-dione based dyes responsible for a sizeable proportion of the remaining market. Azo dyes have many excellent characteristics from a dyeing perspective, but their suspected toxicity following degradation may at some point in the future curtail their use. The synthesis of anthracene-9,10-dione based dyes requires multi-stage synthesis coupled with isomeric separation, and from a commercial viewpoint only blues and reds prove cost effective. By means of simple one-step synthetic modifications this study has shown, that modified naturally occurring anthracene-9,lO-dione based dyes show excellent technical performance in some cases on poly(lactic acid) (PLA) and poly(ethylene terephthalate) (PET). The improvements made over their natural precursors include; higher dye exhaustion, improved colour strength, better saturation chroma (C*), and improvements in light fastness. The most effective derivatives are produced following alkyl substitution across adjacent hydroxyl groups, which yielded cyclic acetals and ethers with improved dyeing characteristics.

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41

Alvares, A. Brenda C. "Ozone pretreatment to improve the biodegradation of recalcitrant textile azo dyes during wastewater treatment". Thesis, Cranfield University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391572.

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42

Choi, Kit-hing. "The bleaching and dyeing industry in Hong Kong : environmental problems and some solutions /". Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18735988.

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43

Abduallah, Bbduelmaged. "Investigating the effect of dyeing on the surface of wool fibres with atomic force microscopy (AFM) /". Link to the online version, 2006. http://hdl.handle.net/10019/948.

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44

Goetz, Charity. "Textile dyes techniques and their effects on the environment with a recommendation for dyers concerning the Green effect /". Lynchburg, Va. : Liberty University, 2008. http://digitalcommons.liberty.edu.

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45

Gonul, Mahmut. "Correlation of plasticizer chemical/physical properties to dyeability and finished characteristics of Nomex Aramid fabrics". Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/8527.

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46

Thompson, Kimberlee Fay. "The role of singlet oxygen in the bleaching of cotton". Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/8680.

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47

Seckin, M. Levent. "Effect of superba heatsetting on dyeing behavior of nylon 6,6 carpet yarns". Thesis, Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/8268.

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48

Low, Kian Sing. "Structure-property relationships of dyes as applied to dye-sensitized solar cells". Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607807.

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49

Unsworth, Christine. "The chemistry of some triphenylmethane dyes". Thesis, University of Central Lancashire, 1991. http://clok.uclan.ac.uk/19774/.

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A comprehensive series of Pyrrole Green dyes containing substituents in the 2-, 3- and 4-positions of the phenyl ring have been synthesised from the relevant carbinols. The steric and electronic effects of the substituents on the visible absorption spectra of the dyes have been examined and linear correlations between A max and appropriate Hammett substituent constants have been established. The rates of hydrolysis of the 4-diethylamino substituted analogue of Pyrrole Green and some 4 1 ,4 11 -bis(N-ethyl-N- 2,2, 2-trifluoroethyl)aminotriphenylmethyl dyes have been studied under a range of different reaction conditions. A stopped-flow technique was used for the study of the fast reactions involved with these dyes. The results from the spectral investigation and the kinetic work indicate that the Pyrrole Green dye series is relatively unstable compared to other related dyes and the reasons for this behaviour are discussed. Pyrrole, pyrrolidine and diethylamino groups have been incorporated into the 2-, 3- and 4-positions of the phenyl ring of Brilliant Green. Spectral characteristics and kinetic data have been examined for the dyes and relevant substituent constants interpolated. The results are discussed in relation to the steric and electronic effects of the heterocyclic moieties. The rate data obtained for each dye studied have been used to derive thermodynamic activation parameters and to test the applicability of an isokinetic relationship in the systems. A novel reaction pathway for the synthesis of pyrroloindoles from 2-pyrrol-l-yl substituted dyes is advanced.

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50

Mon, Jarai. "Sorption and its effects on transport of organic dyes and cesium in soils". Online access for everyone, 2004. http://www.dissertations.wsu.edu/Dissertations/Fall2004/j%5Fmon%5F121504.pdf.

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Tesi sul tema "Dyes and dyeing Chemistry"

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