background: one of the new methods for elimination or destruction of estrogen hormones is ultrasound irradiation. the aim of this study was to determine the main mechanism of steroid hormones removal by ultrasound. methods: in this study, estrogen (e1) and 17 beta-estradiol (e2) were irradiated with ultrasound at different frequencies, powers, and exposure times in two cases: with and without b...

seed coat crude extracts of white-coloured ita-256, white and brown-coloured tvs-716, deep brown-coloured it-90k and light brown-coloured ife brown cowpea varieties were analyzed for the presence and amount of total phenol, tannin and flavonoid content. crude extracts of the cowpea varieties were analyzed for antioxidant activity using the thiobarbituric acid (tba) assay. the seed coat extracts...

Functionalized and fully characterized graphene-based lubricant additives are potential 2D materials for energy-efficient tribological applications in machine elements, especially at macroscopic contacts. Two different reduced graphene oxide (rGO) derivatives, terminated by hydroxyl and epoxy-hydroxyl groups, were prepared and blended with two different molecular weights of polyethylene glycol ...

Astaxanthin (Asx) is known to be a potent quencher of singlet oxygen and an efficient scavenger of superoxide anion. Therefore, Asx would be expected to be a useful antioxidant for the prevention of oxidative stress, a causative factor in severe diseases such as ischemic reperfusion injury. However, it is still unclear whether Asx has scavenging capability against the most potent reactive oxyge...

sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl]ester (saspspe) is employed as a recyclable catalyst for the silylation of hydroxyl groups. a good range of primary, secondary alcohols and phenolic hydroxyl groups were effectively converted into their corresponding trimethylsilyl ethers with hexamethyldisilazane in the presence of catalytic amounts of saspspe at room temperature with short rea...

The main challenge in the oxygen delignification process is the improvement of selectivity. To further understand the effect of the amount of hydroxyl radicals on the selectivity of oxygen delignification, in this work, the hydroxyl radicals were generated by the improved Fenton reaction system and were quantified by UV spectrophotometry. Antioxidants such as ascorbic acid were applied for the ...

The hydroxyl radicals are known to be a biologically active oxygen species. A remarkable enhancement of hydroxyl radical generation was observed in the mitochondria obtained from ischemic myocardium. The hydroxyl radicals are the primary reactive species leading to cellular damages, such as membrane damages, DNA damages, enzyme inactivation, protein denaturation and so forth. The origin of the ...

-The hydroxyl deformation modes of kaolins have been studied by Fourier transform (FT) Raman spectroscopy. Kaolinites showed well-resolved bands at 959, 938 and 915 cm 1 and an additional band at 923 cm ~. For dickites, well-resolved bands were observed at 955, 936.5, 915 and 903 cm I. Halloysites showed less-resolved Raman bands at 950, 938, 923, 913 and 895 cm 1. The first 3 bands were assign...

The polarity of a series of ionic liquids (ILs) based on hydroxyethyl-imidazolium moiety with various anions ([PF(6)], [NTf(2)], [ClO(4)], [DCA], [NO(3)], [AC], and [Cl]) and their corresponding nonhydroxyl ILs was investigated by solvatochromic dyes and fluorescence probe molecules. Most of the nonhydroxyl ILs exhibit anion-independent polarity with similar E(T)(30) in the narrow range of 50.7...