A sensitive determination method was developed for the analysis of pyrethroid pesticide residues in tomato samples using ionic liquid-based dispersive liquid-liquid microextraction. A hydrophobic ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) and acetonitrile were used as the extraction solvent and dispersive solvent, respectively. The following experimental parameters affecting...

All steels contain some amount of dissolved gases such as oxygen, hydrogen and nitrogen of which nitrogen is effective in improving the mechanical and corrosion properties of stainless steels if it remains in solid solution or precipitates as very fine and coherent nitrides or carbo-nitrides with iron or alloying elements. When nitrogen is added to austenitic steels it can simultaneously improv...

A comparative study of ultrasound-assisted extraction (UAE) and hydro-distillation was performed for fast extraction of estragole from tarragon (Artemisia dracunculus L.) dried leaves. Several influential parameters of the UAE procedure in the extraction of estragole (type of solvent, extraction cycles, solvent to material ratio, irradiation time and particle size) were investigated an...

The effects of different solvents, temperature conditions, solvent-solid ratios and particle sizes on solid-solvent extraction of the total phenolics, proanthocyanidins and flavonoids herein also referred to as antioxidant from pomegranate marc peel (PMP) was studied. Water, methanol, ethanol, acetone, and ethyl acetate extraction efficiencies at extraction times of 0.17 to 10 min, extraction t...

Supercritical fluids extraction of emulsions (SEE) is an innovative technique used for the production of micro, nano-particles with controlled size and distribution. Supercritical carbon dioxide (SC-CO2) is used to extract selectively the organic solvents from the droplets of the emulsion, in which the biopolymer is dissolved, producing the precipitation of the polymer and the subsequent format...

The seasonal melting of ice entombed cryoconite holes on McMurdo Dry Valley glaciers provides oases for life in the harsh environmental conditions of the polar desert where surface air temperatures only occasionally exceed 0°C during the Austral summer. Here we follow temporal changes in cryoconite hole biogeochemistry on Canada Glacier from fully frozen conditions through the initial stages of...

dpph radical-scavenging activity of the bene hull oil (bho), sesame oil (seo), rice bran oil (rbo), the oils' methanolic (ch3oh/h2o, 80:20 v/v) or hexane extracts, and their unsaponifiable matters fraction were measured and compared with each other. as a radical-scavenger, seo was significantly stronger than rbo and bho, respectively. unlike bho and rbo, the unsaponifiable (usm) fraction of the...

the phenolic compounds of pomegranate (punica granatum l.) peel extracted by two methods (solvent and ultrasound-assisted) with five solvents (acetone, methanol, ethanol, water and ethyl acetate) were compared with supercritical fluid extraction (sfe). the total phenolic compounds were determined according to the folin-ciocalteu reagent using tannic acid as standard. the overall results showed ...