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Organic Chemistry Nomenclature
Published in Arthur W. Hounslow, Water Quality Data, 2018
DI- and tricarboxylic acids — Dicarboxylic acids are carboxylic acids with two —COOH groups. They are named by counting the total number of carbons in a chain including the carboxyl group and adding dioic acid.
Engineering and Technology of Environmentally Friendly Lubricants
Published in Brajendra K. Sharma, Girma Biresaw, Environmentally Friendly and Biobased Lubricants, 2016
Carlton J. Reeves, Pradeep L. Menezes, Michael R. Lovell, Tien-Chien Jen
Another type of synthetic ester is the diester, a biolubricant derived partly from renewable resources. Synthetic diesters are derived from dicarboxylic acid and monovalent alcohols. The dicarboxylic acid can be prepared from natural sources, such as azelaic acid (from ozonolysis of oleic acid), sebacic acid, dimeric fatty acid, or from purely petrochemical sources, such as adipic acid or malelic acid. Diesters generally consist of branched alcohols, such as EH (iscooctanol), isodecanol, or guerbet alcohols to offer better low-temperature properties than those of conventional synthetic ester lubricants. Additionally, branched fatty acids, for example, 12-hydroxystearic acid derived from ricinoleic acid, can be utilized to form diester-based lubricants that also exhibit improved low-temperature properties [56,57]. Isostearic acid, a synthetic ester-based lubricant consisting of branched and straight-chain C18 fatty acids, has very low levels of unsaturation, resulting in excellent oxidative stability.
Influence of curing agent ratio, asphalt content and crosslinking degree on the compatibility and component distribution of epoxy asphalt in compound curing agent system
Published in International Journal of Pavement Engineering, 2022
Mingyue Li, Zhaohui Min, Qichang Wang, Wei Huang, Zhiyong Shi
Epoxy asphalts with different crosslinking degrees correspond to different properties. In order to ensure that the crosslinking degree of the epoxy asphalt molecular model was consistent with the actual crosslinking degree, Perl language script was applied to construct epoxy asphalt molecular models with different crosslinking degrees, and the algorithm flow chart is shown in Figure 4. Epoxy resin and curing agent were defined as reaction molecules Epoxy, curing agent 1, and curing agent 2 in the epoxy asphalt molecular model respectively. The reactive atoms in the reactive molecules epoxy resin, curing agent 1, and curing agent 2 were further defined as R1, R2, and R3 to simulate the reaction between epoxy groups and acid groups. The reactions between the reactive atoms in the curing agent and the reactive atoms of the epoxy resin were displayed in Figures 5 and 6, respectively. In Figure 5, the carboxylic acid group in the dicarboxylic acid curing agent reacted with the epoxy group directly in the epoxy resin to form a cross-linked macromolecule. In Figure 6, the acid anhydride curing agent reacted with the hydroxyl group in the epoxy resin preferentially to form a carboxylic acid group and an ester bond; then the formed carboxylic acid reacted with the epoxy group in the epoxy resin to build a cross-linked structure.
Vermiremediation – Remediation of Soil Contaminated with Oil Using Earthworm (Eisenia fetida)
Published in Soil and Sediment Contamination: An International Journal, 2021
A study was conducted by (Yang et al. 2020) to check the degradation of pyrene, a highly resistant polycyclic aromatic hydrocarbon in the presence of earthworm (E. fetida) and microbes present in soil. The soil was contaminated artificially with pyrene (200 g) and placed in a container. Microbes and earthworms (E. fetida) were added to this contaminated soil. No mortality of earthworm has been reported, and it resulted in the reduction of (68.7%) of pyrene. Earthworm microbes were responsible for this reduction in unsterilized condition of soil. Twelve enzymes were also produced during this process. Pyrene was transformed into protocatechuic acid from pyrene-4, 5-dione, phenanthrene-4, 5- dicarboxylic acid and phenanthrene −4-carboxylic acid. However, these compounds were not confirmed in their study.
Textile applications of commercial photochromic dyes: part8. A statistical investigation of the influence of photochromic dyes on thermoplastic fibres using a UV-irradiation technique
Published in The Journal of The Textile Institute, 2020
Basel Younes, Stephanie C. Ward, Robert M. Christie
Polyester is generally made by condensing a dihydroxy aliphatic alcohol with a dicarboxylic acid. Most polyester fibres are based on poly(ethylene terephthalate), which was the first commercial fibre-forming polyester developed in 1941 (Broadbent, 2001; Johnson, 1989). Polyester has the most crystalline structure among the man-made fibres that can be dyed by disperse dyes, so that dyeing from aqueous solution must be carried out at a high temperature that can reach 140 °C in order to have a practically sufficient rate of dyeing (Patterson & Sheldon, 1959). Some antioxidants can colour the polyolefin, however they are prone to oxidation by strong oxidising agents such as hydrogen peroxide and concentrated nitric acid. Oxidation leads to reduced mechanical properties and often discolouration as well.