نتایج جستجو برای: ultrasound assisted extraction
تعداد نتایج: 394391 فیلتر نتایج به سال:
abstract: in this study, an analytical method is developed to determine 15 polycyclic aromatic hydrocarbons (pahs) in olive and refined pomace olive oils using hplc coupled with a fluorescence detector. the standardised method of ultrasound-assisted solvent extraction consisted of liquid–liquid extraction with organic solvent and purification on c18 and florisil bonded-phase cartridges was modi...
a method based on the ultrasound-assisted solidification of floating drop microextraction technique was developed for the spectrophotometric and spectrofluorimetric determination of curcumin in turmeric powder. in this work a small volume of an organic solvent was floated on the surface of an aqueous solution. after sonication the organic solvent is solidified and separated. the effect of extra...
in this work, an environmentally friendly sample pre-treatment method, ultrasound assisted surfactant enhanced emulsification microextraction (uaseme) followed with spectrofluorimetry was performed for determination of oxadiazon residues in water samples. after the determination of the most suitable extraction solvent and its volume, other parameters such as type and concentration of surfactant...
in this study, simple and efficient ultrasound-assisted emulsification microextraction (usaeme) combined with gas chromatography-flame ionization detector (gc-fid) was developed for the preconcentration and determination of carbamazepine in biological samples. in this method, the fine droplets of 1-octanol were formed and dispersed in the sample with the help of ultrasonic waves, which accelera...
Teh ultrasound-assisted magnetic stirrer was used as an effective extraction technique for teh evaluation of total phenolic contents (TPC) and antioxidant potential of ten Pakistani brown rice cultivars. For this purpose, ultrasonic (240W frequency 50/60 Hertz) assisted magnetic stirrer coupled with three solvents methanol, ethanol, and isopropanol in pure and aqueous fractions (80:20) were...
The efficacy of decoction in extracting mycobactericidal compounds from Flourensia cernua (Hojasé) leaves and fractionation with solvents having ascending polarity was compared with that of (i) ethanol extraction by still maceration, extraction with a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration, followed by fractionation with n-hexane, ethyl acetate, and n-butan...
in this research, microwave-assisted hydrodistillation (md) with pretreatment ultrasound (us) 45 and 90 min of essential oils from fresh aegle marmelos peel were used and the results were compared with those obtained by hydrodistillation technique (hd) in terms of extraction yield/efficiency, extraction time, chemical composition and quality of the essential oil. all experiments were performed ...
Background The present study optimized ultrasound-assisted extraction conditions to maximize extraction yields of glycyrrhizic acid from licorice. Methods The optimal extraction temperature (X1), extraction time (X2), and methanol concentration (X3) were identified using response surface methodology (RSM). A central composite design (CCD) was used for experimental design and analysis of the r...
Hypericum formosanum is a valuable herb in Taiwan. In this study, response surface methodology was employed to optimize the ultrasound-assisted extraction of flavonoids from Hypericum formosanum. A central composite design with three variables (ethanol concentration, extraction time, and extraction temperature) was applied. Experimental results were fitted to the second order polynomial model a...
We use conventional, microwave and ultrasound assisted sequential extraction, of defined time and power, techniques for extractions of Cd, Cu, Cr, Ni, Pb and Zn in sediments and certified material. We did not change the conditions of extractions through steps, cause we what to see is there difference in extraction results for the certified material and sediments. We use lower powers and time fr...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید