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Stability analysis for tunnel faces supported by means of polymer solutions
Published in Daniele Peila, Giulia Viggiani, Tarcisio Celestino, Tunnels and Underground Cities: Engineering and Innovation meet Archaeology, Architecture and Art, 2020
A polyacrylamide copolymer was chosen for testing, as this type is a typical polymer applied in drilling and as it allows the variation of polymer characteristics. Property variation comprised the chain length and the amount of polymer in solution. The respective properties are given in Table 2. The granular polymer material was slowly sprinkled into 5 l of colored deionized water at pH 7 according to a fixed size distribution of the polymer granules using a magnetic and a mechanical stirrer at 500 rpm. The polymer fluid mixture was stirred for 60 min. Food coloring powder brilliant blue of 0.04 g/l was chosen to visualize penetration of the polymer fluid. Comparison of rheometer flow curves of the colored and uncolored fluid served as validation for equality of rheological performance.
Stability analysis for tunnel faces supported by means of polymer solutions
Published in Daniele Peila, Giulia Viggiani, Tarcisio Celestino, Tunnels and Underground Cities: Engineering and Innovation meet Archaeology, Architecture and Art, 2019
A polyacrylamide copolymer was chosen for testing, as this type is a typical polymer applied in drilling and as it allows the variation of polymer characteristics. Property variation comprised the chain length and the amount of polymer in solution. The respective properties are given in Table 2. The granular polymer material was slowly sprinkled into 5 l of colored deionized water at pH 7 according to a fixed size distribution of the polymer granules using a magnetic and a mechanical stirrer at 500 rpm. The polymer fluid mixture was stirred for 60 min. Food coloring powder brilliant blue of 0.04 g/l was chosen to visualize penetration of the polymer fluid. Comparison of rheometer flow curves of the colored and uncolored fluid served as validation for equality of rheological performance.
Dynamics of Dilute Polymer Solutions
Published in Timothy P. Lodge, Paul C. Hiemenz, Polymer Chemistry, 2020
Timothy P. Lodge, Paul C. Hiemenz
Now we turn to the mutual diffusion coefficient, Dm, which describes how a collection of Brownian particles will distribute themselves in space. In the context of the food coloring analogy, Dt tells us how rapidly any individual dye molecule explores space, but Dm describes how quickly the entire droplet of food coloring disperses itself. Experience tells us that after a reasonable time interval, the glass of water will be uniformly colored. The underlying reason is that mutual diffusion acts to eliminate any gradients in concentration. Although the individual dye molecules are happily diffusing, largely oblivious of one another, collectively they tend to spread themselves out evenly.
Sub-acute exposure to Sudan IV-adulterated palm oil induces oxidative stress and represses the expression of Nrf2 and antioxidant genes in male albino rats
Published in Journal of Environmental Science and Health, Part C, 2021
Ofem E. Eteng, Ceaser A. Moses, Emmanuel I. Ugwor, Joe E. Enobong, Adio J. Akamo, Dorcas I. Akinloye, Irene O. Sadiku, Arikpo Iwara, Eyong Ubana
Sudan IV dye (S4D; C24H2ON4O) is an azo compound used as an industrial dye to color substances like petrol, plastics, oil, soaps, shoe polish, printing inks, and so on. It is a lipophilic diazo dye (lysochrome) used in laboratories as pH indicators and for staining lipids (fats and lipoproteins).3 Due to its intense red-orange color and low cost, S4D was used as a food coloring agent until safety concerns were identified. Although S4D has been ruled unsafe under the 1995 Colors in Food Regulations, due to its harmful effects and is considered an illegal food dye, it has continued to be incorporated surreptitiously in some food products, such as palm oil, chili powder, and egg products, as well as poultry meat around the world.3 A survey of palm oil and chili spices in Washington, DC, United States, revealed S4D as the primary azo-dye in palm oil, with concentrations reaching 24 µg/mL, which is higher than the EU detection limits of 0.6 − 1.2 µg/mL.4 A more recent study confirmed the adulteration of palm oil samples with S4D, previously reported by the Food and Drug Authorities of Ghana.5 The upsurge in the use of palm oil, particularly in homemade and ready-to-eat meals, and its bright reddish color makes it a prime target for adulteration with S4D; a practice that has continued to persist.5
Fixed bed mycofilter column optimization and performance evaluation through the removal of a food coloring agent from an aqueous solution
Published in Bioremediation Journal, 2023
Sanele M. Mnkandla, Patricks Voua Otomo
The food coloring solution was prepared by diluting the commercially available Moir’s sky blue food color [containing: brilliant blue FCF (E133), brillantcarmoisin O (E122), acidity regulator (E330), extra neutral ethanol, preservatives (E218), sodium benzoate (E211)] with distilled water, at pH = 7.5, or adjusted to pH = 2 using 0.1 M HCl. To determine the blue dye concentration, a standard curve was prepared from serial dilutions. Absorbances were measured at 629 nm using a Jenway 7300 spectrophotometer. The concentration was calculated using Beer’s law: where A = absorbance; ε = molar absorptivity; b = path length of light and c = concentration.
Removal of tartrazine, ponceau 4R and patent blue V hazardous food dyes from aqueous solutions with ZnAl-LDH/PVA nanocomposite
Published in Journal of Dispersion Science and Technology, 2023
Ofeliya O. Balayeva, Abdulsaid A. Azizov, Mustafa B. Muradov, Rasim M. Alosmanov
The purpose on the selection of tartrazine, ponceau 4R and patent blue V in the experimental work:Tartrazine is a synthetic azo dye with yellow color mainly used as a food and pharmaceutical colorant with C16H9N4Na3O9S2 chemical formula. It is also known as Yellow 5, Acid Yellow 23, Food Yellow 4, trisodium 1-(4-sulfonatophenyl)-4-(4-sulfonatophenylazo)-5-pyrazolone-3-carboxylate) and E102 has a maximum absorbance in an aqueous solution at 426 nm.[12] Because its negative effects on living organisms (damage to white blood cells, allergic and intolerance reactions, etc.) are found more over time, in some countries there are even some restrictions on its use.Ponceau 4R - is a synthetic azo-dye (red color) with C20H11N2Na3O10S3 chemical formula that can be used in many food products and is normally synthesized from organic aromatic compounds. It is also known as Cochineal red A, C.I. acid red 18, Brilliant scarlet 3R, Brilliant scarlet 4R, New coccine and E124. In some countries ponceau 4R is classifed as a carcinogen and its use is prohibited[13,14]Patent blue V, also called Food Blue 5, Sulphan Blue, Acid Blue 3 or Sky Blue and E131, is a synthetic triphenylmethane dye with C54H62N4O14S4Ca chemical formula used as a food coloring.[15] patent blue V is banned as a food dye in Australia and US, because health officials in these countries suspect that it may cause allergic reactions, with symptoms ranging from itching[12] and nettle rash to nausea, hypotension, and in rare cases anaphylactic shock; it is therefore not recommended in those countries for children.[16]