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251.
Natural dyes are not harmful to the environment owing to their biodegradability. For dye application to textiles, salts are necessary as mordant or electrolytes and make an environmental impact. In this paper, the influence of cationization during mercerization to the dyeing of cotton fabric with natural dye from Dactylopius coccus was researched. For this purpose, bleached cotton fabric as well as fabric cationized with Rewin OS was pre-mordanted using iron(II) sulfate heptahydrate (FeSO4·7H2O) and dyed with natural cochineal dye with and without electrolyte addition. For the characterization of surface changes after cationization, an electrokinetic analysis on SurPASS was performed and compared to pre-mordanting. For determination of dye exhaustion, the analysis of dye solution was performed on a UV/VIS spectrophotometer Cary 50 Solascreen. Spectrophotometric analysis was performed using a Datacolor 850 spectrophotometer, measuring remission ”until tolerance” and the whiteness degree, color parameters, color depth (K/S), and colorfastness of dyed fabric were calculated. Levelness was determined by visual assessment. Cationized cotton fabrics showed better absorption and colorfastness. Pre-mordanting and cationization showed synergism. The electrolytes improved the process of dye absorption. However, when natural dyeing was performed on cotton fabric cationized during mercerization, similar chromacity, uniform color, and colorfastness were achieved with and without electrolyte, resulting in pure purple hue of cochineal. For achieving a violet hue, pre-mordanting with Fe-salt was needed. Therefore, salt can be reduced or even unnecessary, which makes this process of natural dyeing more environmentally friendly. 相似文献
252.
Iva Slavova Teodora Tomova Slavena Kusovska Yoana Chukova Mariana Argirova 《Molecules (Basel, Switzerland)》2022,27(6)
Tamus communis L. is a plant distributed in a number of geographical areas whose rhizome has been used for centuries as an anti-inflammatory and analgesic remedy. This review aims to summarize the current knowledge of the chemical composition and biological activity of the extracts or individual compounds of the rhizome. The data for the principal secondary metabolites are systematized: sterols, steroidal saponins, phenanthrenes, dihydrophenanthrenes, etc. Results of biological tests for anti-inflammatory action, cytotoxicity, anticholinesterase effect, and xanthine oxidase inhibition are presented. Some open questions about the therapeutic properties of the plant are also addressed. 相似文献
253.
Bojinov Martin Betova Iva Karastoyanov Vasil 《Journal of Solid State Electrochemistry》2023,27(7):1835-1846
Journal of Solid State Electrochemistry - Anodic film growth on a Ti alloy in water-containing ethylene glycol electrolyte with addition of fluoride... 相似文献
254.
255.
Lea Vuletić Ivana Lapić Stjepan Špalj Iva Marolt Banek Domagoj Jakovac Jasmina Šipkar Dunja Rogić 《Electroanalysis》2023,35(5):e202200399
Ion-selective electrode pocket meters available for use with saliva could be a convenient tool to assess how diseases, drugs, exercise or nutrition affect salivary composition. This study compared salivary sodium and potassium concentrations measured by handheld LAQUAtwin meters and a fully-automated biochemical analyzer. Agreement between two methods was assessed with Passing-Bablok regression and Bland-Altman plots. LAQUAtwin meters measured lower values of both analytes and provided repeatable though not accurate results. The meters may serve as an alternative to laboratory methods to gain insight into between-group differences in electrolyte concentrations, or a concentration change induced by an experimental procedure. 相似文献