styrene is an important constituent of widely used organic solvents in industries for production of various synthetic materials. the use of solid-phase extraction (spe) has grown and is a fertile technique of sample preparation as it provides better results than those produced by liquidliquid extraction. in this study, spe has been optimized, regarding sample ph, sample concentration, sample fl...

recently, 6-(2-naphthyl)-2, 3-dihydro-as-triazine-3-thione (ndtt) was synthesized in laboratory and used successfully for the spectrophotometric determination of nanogram levels of cu2+ in aqueous solution. this reagent forms a specific red complex with cu2+ ions after the extraction by chloroform at alkaline ph. the absorption of the complex in the uv region (313 nm) is about 8 times as strong...

the applicability of hollow fiber-based liquid phase microextraction (hf-lpme) was evaluated for the extraction and preconcentration of loratadine prior to determination by hplc. in order to obtain high extraction recovery, the parameters affecting the hf-lpme including type of organic phase, ph of the source and receiving phases, stirring rate, extraction time and salt addition were studied an...

A new method was established for the simultaneous determination of the migration amounts of bisphenol A (BPA) and phenol from polycarbonate (PC) bottles based on subcritical water extraction (SWE) and high performance liquid chromatography. The optimum extraction conditions included an extraction temperature of 120 degree C, a pressure of 6.89 MPa (1000 psi), a static extraction time of 1 h and...

This paper describes a new separation process of liquid-liquid extraction. It consists of first mixing the system to be extracted with a primary solvent, which is soluble with the native solvent, and subsequently adding a modifier, which is insoluble with either the native or the primary solvent. This process is similar to the phase transition extraction, which was described in a previous paper...

A capacitance measurement system is developed for the measurement of gas-liquid two-phase flow in glass micro-pipes with inner diameters of 3.96, 2.65 and 1.56 mm, respectively. As a typical flow regime in a micro-pipe two-phase flow system, slug flow is chosen for this investigation. A capacitance sensor is designed and a high-resolution and high-speed capacitance measurement circuit is used t...

The work presented in this thesis concerns the development and evaluation of new methods for sampling and analysis of organic pollutants in the indoor and outdoor environment. In Paper I, the development of a new method was reported for the determination of the brominated fl ame retardant tetrabromobisphenol A (TBBPA) in air using sampling with glass fi ber fi lter and polyurethane foam (PUF), ...

The review of the RP HPLC analysis of basic psychotropic drugs is presented. It contains sample preparation methods with centrifugation, protein precipitation, liquid-liquid extraction (LLE), dispersive liquid-liquid microextraction (DLLME), solid-phase extraction (SPE), solid-phase microextraction (SPME), microwave-assisted extraction (MAE) and RP-HPLC analysis. Chromatographic behavior of bas...

A review. In this paper, separation of metals with solvent extraction, ionic liquid extraction phase and chelate extraction of metal ion were reviewed.