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...

IntroductIon Polyphenols are a large family of metabolic compounds that occur naturally in a wide variety of plant foods. Recently, polyphenols have attracted a great deal of attention due to their roles as natural antioxidants. Antioxidants are believed to provide a protective effect against oxidative damage diseases such as cancer, coronary heart disease, and stroke. It has been estimated tha...

efforts to increase the mass transfer coefficient, enhance the contact area, and decrease the power input of contractors have given risen to the development of the pre-dispersed solvent extraction (pdse) contactor and the devise of the new dissolved nitrogen pdse (dnpdse) contactors. the studies conducted after the design of the new contactor to determine the working conditions for its suitable...

INTRODUCTION Underground storage tanks containing hydrocarbonbased fuels are found worldwide. Many of these tanks have leaks, allowing gasoline, diesel, oil, or other hydrocarbon materials to contaminate the surrounding soil. In 1992, only 2 million of the 5 million tanks in the U.S. were monitored for leaks. However, underground storage tanks represent only one of many sources of hydrocarbon c...

The present study was aimed at examining the distribution and abundance of glycerol dialkyl glycerol tetraethers (GDGTs) of archaeal and bacterial origin in peat samples from surface and deep (ca. 50 cm) horizons of a peat bog in the Jura Mountains (northeastern France). Two principal types of GDGTs are present: extractable GDGTs, recoverable by solvent extraction, and non-extractable GDGTs, li...