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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

An in vivo study of how calcium cages affect the calibration of calcium indicator dyes /

Patino, Nicole, January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaf 58). Also available on the Internet.
212

Studies on the metabolism of carcinogenic aminoazo dyes

Brown, Raymond R. January 1953 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1953. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
213

Surface modification and chromophore attachment via ionic assembly and covalent fixation

Hubbell, Christopher January 2009 (has links)
Thesis (M. S.)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2009. / Committee Co-Chair: Beckham, Haskell; Committee Co-Chair: Cook, Fred; Committee Member: Collard, David; Committee Member: France, Stefan; Committee Member: Griffin, Anselm
214

A study of ellipsoidal variance as a function of mean CIELAB values in a textile data set /

Ansell, Seth. January 1995 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1995. / Typescript. Includes bibliographical references (leaves 130-131).
215

An in vivo study of how calcium cages affect the calibration of calcium indicator dyes

Patino, Nicole, January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaf 58). Also available on the Internet.
216

Fluorescent polyctosine-encapsulated silver nanoclusters

Antoku, Yasuko. January 2007 (has links)
Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2007. / Dickson, Robert, Committee Chair ; Barry, Bridgette, Committee Member ; Fahrni, Christoph, Committee Member ; Fernandez, Facundo, Committee Member ; Srinivasarao, Mohan, Committee Member.
217

Determinação de corantes de cabelo e derivados em água e tintura comercial por cromatografia líquida de alta eficiência

Franco, Jefferson Honorio [UNESP] 17 May 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-05-17Bitstream added on 2014-06-13T19:38:04Z : No. of bitstreams: 1 franco_jh_me_araiq.pdf: 2988463 bytes, checksum: 88bd780cb08b82dfd5bdd91af395a305 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A tintura de cabelo é um processo adotado por milhões de pessoas, independente da raça, sexo, nacionalidade, religião ou idade. No entanto, os métodos analíticos disponíveis para avaliação destes produtos em formulação comercial, efluentes de salão de beleza, esgotos e águas superficiais são escassos. O presente trabalho investiga o desenvolvimento de um método analítico baseado em cromatografia líquida de alta eficiência com detector de arranjo de diodos para determinação dos corantes: Azul básico 99, Violeta ácido 43, Marrom básico 16, Vermelho básico 76 e Amarelo básico 57, usados em tinturas semipermanentes de cabelo. As melhores condições experimentais para separação dos corantes de cabelo de interesse foram: acetonitrila/água 35:65 (v/v) com adição de 4,0 x 10-2 mol L-1 de líquido iônico tetrafluoroborato de 1-butil-3-metilimidazólio (BMIm-BF4), à fase móvel, vazão: 0,4 mL min-1. Nestas condições experimentais observa-se melhor resolução e definição dos picos presentes nos cromatogramas nos respectivos tempos de retenção: AB 99 (tr =8,80 min), VA 43 (tr =14,78 min), MB 16 (tr =19,10 min), VB 76 (tr =25,08 min) e AB 57 (tr =34,17 min), confirmados pelos respectivos espectros hidrodinâmicos UV-Vis obtidos e comparados com o padrão de cada corante. O uso de liquido iônico como aditivo da fase móvel mostrou-se relevante para a detecção de corantes de cabelo melhorando significativamente a separação e encaudamento dos picos. Curvas analíticas foram construídas para cada corante de cabelo no intervalo de concentração de 1,0x10-7 a 8,0x10-5 mol L-1. O índice de recuperação dos corantes em água fortificadas por cada corante indicou valores entre 84 – 117 %. Amostras da tintura de cabelo comercial (HF 65, Arianor) foram submetidas à análise usando o método proposto e a concentração obtida... / The hair dye is a process used by millions of people regardless of race, sex, nationality, religion or age. However, the analytical methods available for evaluating these products in pharmaceutical formulation effluent salon, sewers and surface waters are scarce. This paper investigates the development of an analytical method based on high performance liquid chromatography with diode array detector for determination of dyes: Basic blue 99, Acid violet 43, Basic brown 16, Basic red 76 and Basic yellow 57 dyes used in semipermanent hair. Optimum conditions for separation of hair dyes of interest were acetonitrile / water 35:65 (v / v) with addition of 40 x 10-3 mol L-1 ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate (BMIm-BF4), to the mobile phase flow rate: 0,4 ml min-1. Under these experimental conditions is observed better resolution and definition of these peaks in the chromatograms in the respective retention times: 99 AB (tr = 8.80 min) and VA 43 (tr = 14.78 min), 16 MB (tr = 19, 10 min), VB 76 (tr = 25.08 min) and 57 AB (tr = 34.17 min), confirmed by the respective UV-Vis spectra hydrodynamic obtained and compared with the pattern of each dye. The addition of ionic liquid additive as the mobile phase was found to be relevant for the detection of hair dyes significantly improved separation and peak tailing. Curves were constructed for each hair dye in the range of 1x10-7 to 8x10-5 mol L-1. The recovery rate of dyes in fortifield water indicated values between 84-117%. Samples of commercial hair dye (HF 65, Arianor) were analyzed using the proposed method and the concentration obtained for the dyes in the dye indicated the occurrence of AB 99, VA 43, MB 16, VB 76 and AB 57 in a concentration of 4,33 x 10-5, 8,81 x 10-6, 5,86 x 10-6, 1,31 x 10-4 and 1,99 x 10-5 mol L-1, respectively. The analytical method... (Complete abstract click electronic access below)
218

Small-scale sustainable vegetable-tanned leather in rural South Africa: a collective-efficiency approach

Munyai, Keneilwe January 2014 (has links)
Thesis submitted in fulfilment of the requirements for the degree: Doctor of Technology: DESIGN In the Faculty of Informatics and Design At the Cape Peninsula University of Technology / Currently, the South African leather tanning industry is dominated by chromium tanning which has been identified as highly polluting. Vegetable tanning is considered less environmentally hazardous. Yet, there have been no plans to promote it in South Africa. Vegetable tanning process utilises vegetable matter for converting animal skins or hides into pliable material that is known as leather. South Africa has a variety of plants that produce tannins. However, the focus of this study is on the mimosa locally known as black wattle (Arcacia miernsii). Furthermore, the South African vegetable tanning sector has been left behind in terms of research and development despite the country being endowed with the Mimosa plant that is widely used in the vegetable tanning process. The country is also endowed with surplus labour which can be absorbed by the leather industry which is labour intensive.
219

Estudo da difusão de corantes reativos em tecido de algodão / Study of diffusion of reactive dyes on cotton fabric

Moraes, Cristina Martins de 12 October 2010 (has links)
Orientador: Sergio Persio Ravagnani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-17T05:16:10Z (GMT). No. of bitstreams: 1 Moraes_CristinaMartinsde_M.pdf: 2017261 bytes, checksum: d141b3709280cc5f5c7dd69653b570e6 (MD5) Previous issue date: 2010 / Resumo: O processo de tingimento destinado à área de acabamento nas indústrias têxteis tem relevada importância, onde o corante deve ter boa afinidade com as fibras para garantir a uniformidade da cor. O corante é o principal responsável pela poluição ambiental, já que apresenta elevada durabilidade, e são considerados de difícil degradação natural. Como atualmente as leis ambientais estão cada vez mais rígidas, preservando os recursos naturais, as indústrias tem buscado alternativas que minimizam os custos de tingimento e que reduzam os impactos ambientais. Uma melhor interação corante / fibras resulta em uma melhor transferência de massa de corante do banho para as fibras, devendo garantir que se atinja o equilíbrio do processo. Com a finalidade de determinar o grau de difusividade entre os corantes e a afinidade corante / fibras durante o processo de fixação, neste trabalho analisou-se o processo de difusão por meio dos quais os corantes reativos são adsorvidos nas fibras de algodão. Através dos ensaios experimentais, conseguiu-se determinar a concentração de corante / tempo sobre seu grau de esgotamento (equilíbrio) para quatro corantes distintos. Nos ensaios de tingimento determinou-se a concentração / tempo de cada corante no banho residual através da Espectrofotometria por meio de Absorbância e nas amostras de tecido obteve-se a quantidade de cor difundida nas mesmas pelo Método de Colorimetria, Sistema CIE. Com os ensaios verificaram-se todos os componentes presentes no banho e constatou-se uma linearidade entre a concentração de corante no banho residual e a concentração de cor nas fibras (tecido) entre os corantes usados. Através dos ensaios experimentais, correlações foram obtidas entre os corantes tintos a frio representando o processo, para estabelecer a quantidade de corante adsorvido pelas fibras de algodão. Uma simulação também foi feita utilizando o Modelo de Difusão em cilindros a partir das Leis de Fick para se determinar o Coeficiente de Difusão de cada corante, o que corresponde ao seu grau de difusividade / Abstract: The process of dyeing destined to the area of finishing textile industries has in relief importance, where the dye must have affinity with fiber to ensure the uniformity of color. The dye is chief for environmental pollution, since it has certain durability, and are considered the difficult natural degradation. As environmental laws currently are increasingly rigid, preserving the natural resources, the industries have sought alternatives which minimize the costs of dyeing and which reduce the environmental impacts. A better interaction dye / fiber results in better transfers of mass dye of the bath for fiber, should ensure that it reaches the equilibrium process. In order to determine the degree of diffusivity between the dyes and the affinity dye / fiber during the process of fixation, in this work analyzed-if the process of diffusion by which the reactive dyes are adsorbed in cotton fiber. Through the experimental tests, could be determine the concentration of dye / time about his degree exhaustion (equilibrium) for four dyes distinct. In the tests of the dyeings determined concentration / time of each dye in bath residual through Spectrophotometry by means of Absorbance and in tissue samples obtained-if the quantity of color diffused in the same by the method Colorimetry, CIE System. With the tests there were all components present in the bath and chief linearity between the concentration of the dye in bath residual and concentration of color in the fiber between the dyes used. Through the experimental tests, correlations were obtained between the dyes reds cold representing the process, to establish the quantity of the dye adsorbed by the cotton fibers. A simulation was also made by using the Model of Diffusion in cylinders from the laws of Fick to determine the Coefficient the Diffusion of the each dye, which corresponds to the degree of diffusivity / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química
220

Tingimento com pigmento natural: um estudo empírico para redução do consumo de água utilizando máquina de lavanderia em peças confeccionadas com matéria prima 100% algodão / Dyeing with natural pigment: an empirical study for reduction of water consumption, using laundry machines in dyeing of pieces 100% cotton.

Nelson Barros Trindade 14 December 2015 (has links)
Neste trabalho que trata da redução do consumo de água na fase do tingimento das roupas fabricadas com malha de algodão, foi desenvolvido um método utilizando pigmento natural Urucum Especial com o objetivo de diminuir o consumo de água e avaliar os resultados, comparando-os com aqueles que são conseguidos atualmente pelos métodos de tingimento com pigmento natural Urucum pelo método tradicional e o método de tingimento com corante sintético Direto. Para assegurar que o processo proposto pudesse ser aplicado em escala industrial, o trabalho foi desenvolvido em equipamentos pilotos da empresa Donacor, do Senai Têxtil Francisco Matarazzo e da Universidade de São Paulo. Cada tingimento foi feito em triplicata, avaliando-se o consumo de água, a solidez à água, ao suor e à luz. Demonstrou-se que o processo Urucum Especial pode ser utilizado industrialmente como um método alternativo cujo consumo de água é menor que o método tradicional utilizado para tingir com o pigmento urucum. A redução no consumo de água foi de 38 litros por quilogramas de roupa tingida em relação ao processo utilizado com corante Direto e 68 litros com o processo utilizado para tingir com pigmento urucum. Os ensaios de solidez à água e ao suor nos três processos testados não apresentaram valores significativos, enquanto que os ensaios de solidez à luz do processo Urucum Especial pelo método proposto obtiveram notas máximas. A intensidade coloristica do processo Urucum Especial ficou 3,65 unidades maior do que o processo Urucum Esgotamento, apresentando melhor rendimento tintorial e demonstrando que o processo Especial pode ser executado como alternativa ao processo convencional com otimização no rendimento do pigmento natural / In this work which deals with the reduction of water consumption in the dyeing phase of the clothes made of cotton fabric, a method was developed using natural pigment Urucum Special with an aim to reduce water consumption and evaluate the results, comparing them with those that are currently obtained by the dyeing methods with natural pigment Urucum by the traditional method and the dyeing method with Direct synthetic dye. To ensure that the proposed process could be applied on an industrial scale, the work was carried out in pilot equipments at Donacor company, at Senai Textile Francisco Matarazzo and at the University of São Paulo. Each dyeing was done in triplicate evaluating the consumption of water, water fastness, light and sweat. It has been shown that the special process can be used industrially as an alternative method the water consumption is lower than the traditional method used for dyeing with pigment. The reduction in water consumption was 38 liters per kilogram clothing dyed in relation to the process used in direct dye and 68 liters process used for dyeing with pigment. Strength tests and sweat water in the three cases tested showed no significant amounts, while the light fastness test of the special process obtained by the proposed method top marks. The coloristic intensity of Special process was 3.65 units higher than the Urucum conventional process, with better dyeing yield and demonstrating that the Special process can be performed as an alternative to the conventional process by optimizing the yield of natural pigment

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