Colour prediction as a weaving design selection help tool in Jacquard CAD

The final colour prediction of a weave design made of dyed yarns is a difficult problem. This study shows how a geometric model can be developed to obtain the final colour prediction objectively. For this purpose, a woven material was divided into weft, warp and pores. Then, all parameters needed for the calculation of each colour contribution were identified. A geometrical model based on construction parameters was developed to predict the surface colour contribution of each coloured yarn in a weave surface. To validate the predicted colorimetric data, a visual assessment experiment was conducted. Then, the difference between the predicted and actual colour appearance of the weave pattern was evaluated and analysed in function of weaving structures, and weft yarns colours. For this purpose, simple woven structures (plain, twill 1/3, basket 2/2 and satin Turc) with four coloured weft yarns were used. Results show that the proposed model could correctly predict the final colour of weave designs. Therefore, the model has the potential to eliminate subjective evaluations and reduce prototype sample production by automating the process of weave/colour simulation, thereby reducing the cost and time for product development. The methods of utilization of colour in woven textiles depend upon the composition of the weave design to be woven and the structure parameters of the cloth

Effects of olive oil and its fractions on oxidative stress and the liver's fatty acid composition in 2,4-Dichlorophenoxyacetic acid-treated rats

<p>Abstract</p> <p>Background</p> <p>Olive oil's beneficial effects are not only related to its high content of oleic acid, but also to the antioxidant potential of its polyphenols. In this study, we assess the effects of virgin olive oil and its fractions on 2,4-D- induced oxidative damage in the liver of rats.</p> <p>Methods</p> <p>Male Wistar rats were randomly divided into eight groups of ten each: (C) a control group, (D) group that received 2,4-D (5 mg/kg b.w.), (D/EVOO) group treated with 2,4-D plus extra virgin olive oil, (D/OOHF) group that received 2,4-D plus hydrophilic fraction, (D/OOLF) group treated with 2,4-D plus lipophilic fraction, (EVOO) group that received only extra virgin olive oil, (OOHF) group given hydrophilic fraction and (OOLF) group treated with lipophilic fraction. These components were daily administered by gavage for 4 weeks.</p> <p>Results</p> <p>A significant liver damage was observed in rats treated with 2,4-D via increased serum levels of transaminases and alkaline phosphatase, hepatic lipid peroxidation and decreased hepatic antioxidant enzyme activities, namely, superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. The liver's fatty acid composition was also significantly modified with 2,4-D exposure. However, extra virgin olive oil and hydrophilic fraction intake during 2,4-D treatment induced a significant increase in the antioxidant enzyme activities and a decrease in the conjugated dienes (CD) and thiobarbituric acid-reactive substances (TBARs) levels in the liver. The lipophilic fraction supplemented to 2,4-D- treated rats did not show any improvement in the liver oxidative status while a marked improvement was detected in the hepatic fatty acid composition of rats supplemented with olive oil and the two fractions.</p> <p>Conclusion</p> <p>We concluded that the protective effect of olive oil against oxidative damage induced by 2,4-D is mainly related to the antioxidant potential of its hydrophilic fraction.</p

Ecological contribution of Fenton process for generation of a ready-to-reuse dyeing and finishing effluent

In this study, real wastewater from a dyeing factory and previously treated by biological processes was decolorized by Fenton oxidation. Direct and reactive dyebaths and the related auxiliaries constituted the polluted effluents. A synthetic wastewater was also prepared in the same way in order to compare degradation performance. The study was performed with a systematic approach, searching optimum values of H2O2 and FeSO4 concentrations, pH, temperature and the chemical structure of each tested dye. Depollution results showed that the oxidation behaviour of synthetic and real wastewaters was very similar, especially during the first stage where the breaking of chromophore groups allowed fast colour removal. However, it was found that higher ratios of [H2O2]/[FeSO4] must be engaged in the case of real wastewaters. Results also showed that the catalytic oxidation yielded a fast and complete depollution at [H2O2]/[FeSO4] = 70, pH 3 and temperature 40°C. For experiments with direct dye, colour and COD removals were, respectively, 90% and 87% in the case of real wastewater. Reactive real wastewater showed non-stable oxidation evolution due to the hydrolysed dyestuff and this led to 83% and 45% decolourization and COD removal, respectively. Better depollution results were noted for the synthetic wastewater experiments. This finding was related to the non-stable composition of the real wastewater and the unknown chemical and physical interferences between its compounds. After sedimentation, reuse of the treated wastewater for new dyeing experiments was also investigated. For this purpose, the whole process was run under complete recycling mode and the previously treated effluent was re-used as fresh dyebath. Results in terms of colour depth and fastness showed that dyeing performances were very similar, and an important opportunity is offered by reusing wastewater treated by Fenton oxidation process

Effect of Grafted and Dyed Polyamide Nets on the Adhesion of Three Marine Bacterial Strains

Marine biofouling seriously affects the field of aquaculture. On the one hand, it causes structural fatigue of nets and on the other hand, it has harmful consequences on the health of farmed species. The aims of this study were to develop antibacterial nets using methacrylic acid and dyes. At first, polyamide 6.6 nets were grafted with methacrylic acid following two methods and dyed with 3 specific dyes. Then, modified nets were evaluated with SEM and XPS to obtain morphological and chemical information. Moreover, the antibacterial activity of nets was assessed against three bacterial strains at a laboratory scale and at a real scale by calculating the Colonies Forming Units (CFU) / gram. All treated nets showed an inhibition level higher than 65%. Besides, nets dyed with direct dye Tubantin and grafted with MA after plasma activation, showed an inhibition level higher than 95%. Also, nets modified with MA after plasma and reactive dye Bezaktiv S showed the best antifouling activity against three bacteria strains