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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.
181

The development of a laboratory procedure for dyeing nylon knits, for reproducibility of shades and levelness, using a mixture of three dyes

Cook, Gail Ferguson January 1974 (has links)
The study was conducted to determine congruence in the role of principals of vocational-technical centers in Virginia as perceived by principals, superintendents, and teachers. Twenty-three out of the 24 vocational-technical centers in the state were included in the study. There were 23 superintendents, 23 principals, and 65 teachers from a 20 percent sample who provided useable returns. Design and method of research. A list of 78 items believed to be the functions of principals of vocational-technical centers was developed from the literature and subjected to a jury of experts. Forty-eight items were included in the final instrument which utilized a Likert-type scale to measure perceptions of the respondents. The mail questionnaire technique was used. Analysis of data. Means and standard deviations were obtained on each item for each of the three subgroups. Factor analysis of the items resulted in the identification of six factors underlying the 48 functions. A z-test was used to determine the differences between the sample of teachers, and the principals and superintendents on each factor. / M.S.
182

Zero-Valent Iron Decolorization of the Anthraquinone Dye Reactive Blue 4 and Biodegradation Assessment of its Decolorization Products

Yang, Hanbae 18 April 2005 (has links)
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.
183

Development of commercial, sustainable processes for dyeing generic, unmodified polypropylene fiber

Gupta, Murari Lal 25 August 2008 (has links)
Identification of viable vat dye candidates of a trichromatic series (compatible red, yellow and blue colorants) plus an orange based on the developed single-stage acid leuco vat dyeing process for unmodified polypropylene (PP) flat woven fabrics has been achieved with adequate fastness properties to washing, crocking and dry-cleaning: C. I. Vats Orange 1, Yellow 2 and Red 1 have been certified, whereas Vat Blue 6 is a marginal candidate. Vat Blue 1 has been demonstrated to be a viable colorant for dyeing of PP fiber as a single colorant. Molecular dynamics simulation and solubility parameter (SP) approaches have been utilized to screen the potential vat dye candidates for generic PP coloration. Experimental K/S results have exhibited good correlation with the predicted mixing energy of acid leuco vat dyes-PP fiber and the calculated dyes' SP's. The low SP/mixing energy acid leuco vat dyes (e.g., C. I. Vat Red 1) have shown better color-yield/fastness properties than the high SP/mixing energy vat dyes (e.g., C. I. Vat Brown 1), exhibiting that increasing difference of SP between the vat dye and the PP fiber, coupled with a higher mixing energy of dye-PP blend, resulted in decreased interactions between the two. For example, C.I. Vat Brown 1 with its high SP and calculated mixing energy with PP gave least color yield than the certified vat dyes, all with lower SP's and mixing energies. Cross-section micrographs of the dyed fibers revealed the absence of "ring-dyeing". Experimentally determined kinetic parameters such as affinity of dyeing and heat of dyeing quantified the presence of interaction between acid leuco vat dyes and PP fiber. Tensile test and X-ray crystallinity results have confirmed that dyeing process did not alter the tensile strength and modulus of the dyed PP textiles significantly. PP Fabrics dyed with simulated continuous dyeing processes (pad-steam and pad-dry heat) demonstrated good color yields and levelness with adequate fastness to crocking, washing and dry cleaning.
184

The bleaching and dyeing industry in Hong Kong : environmental problems and some solutions /

Choi, Kit-hing. January 1997 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 92-93).
185

A Study of the Design Possibilities and Techniques of Pounding Plants into Fabric and Paper

Safford, Gayle Grisham 08 1900 (has links)
The problem of investigating the possibilities of direct design transfer from plant to fabric and paper was divided into two parts. The first part is concerned with the exploration of the mechanics of the transfer. Invloved in this process are the technique of manipulating tools, of selecting suitable fabrics and paper, of determining chemicals that would facilitate the printing process and of experimenting with ways to preserve the finished design. The evaluation of the usability and durability of the finished print was based on a series of color fastness tests. The second part of this problem is concerned with the exploration of the design possibilities of the medium. The plants were tested and rated according to their visual attributes relative to the elements of design. Combinations of the successful plant prints were used to produce variations of pattern and texture. The results of the investigation were evaluated to determine the versatility of the medium as a design tool and the usefulness of the technique as a practical printing method
186

The effects of commercial insecticide products on acid and disperse dyes on nylon carpet fiber

Pourboghrat-Afiat, Frozan. January 1985 (has links)
Call number: LD2668 .T4 1985 P68 / Master of Science
187

Decolorisation of phenolic industrial wastes using Trametes versicolor

Summerwill, Michah January 1994 (has links)
No description available.
188

Development and characterisation of a propriety polymer matrix for enhanced optical properties

27 January 2014 (has links)
M.Tech. (Biomedical Technology) / Please read abstract in the full-text document
189

Metal and nonmetal doped semiconductor photocatalysts for water treatment

01 July 2015 (has links)
PhD. (Chemistry) / Please refer to full text to view abstract
190

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

Franco, Jefferson Honorio. January 2012 (has links)
Orientador: Maria Valnice Boldrin / Banca: Marilda das Dores Assis / Banca: Marcio Fernando Bergamini / Resumo: 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... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: 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) / Mestre

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