In the first part of this paper, an ultrasonic injection port was used to evaporate propoxur, as a thermally unstable compound, in ion mobility spectroscopy with a corona discharge source. The liquid-liquid extraction method was performed to extract propoxur from an aqueous medium. Methanol and trichloromethane were used as dispersing and extracting solvents, respectively. The extraction parameters were investigated and optimized using the response surface methodology. Under optimal conditions, a linear range was obtained in the 5-80 μg / L concentration range. The detection limit value was 2.1 μg / L. The relative standard deviation of the measurements was 7%. This method measured propoxur in 3 water samples, including agricultural wastewater, aviculture wastewater, and well water. The relative recovery for the samples was between 91 and 105%. In the second part, a covalent organic framework was synthesised under sealed tube conditions, based on the condensation reaction between amine and anhydride. The synthesized COF was then coated on a stainless steel wire and used in the solid phase microextraction method as the extraction phase. In order to eva‎luate the synthesized adsorbent, chlorpyrifos and trifluralin were selected as model species and finally separated and identified by gas chromatography with a detector with a corona discharge ion mobility spectrometer. Under optimal conditions, a detection limit of 0.15 μg / L and 0.13 μg / L were obtained for chlorpyrifos and trifluralin, respectively. The linear range of the method was 0.50-50 μg / L for chlorpyrifos and 0.45-20 μg / L for trifluralin. In this method, the relative standard deviation within the day and between days was calculated in the range of 4-6% and 9-11%, respectively. Also, the relative standard deviation between the prepared fibres was 9%. The proposed method measured the species in aqueous samples of waters, fruits and vegetables. Recovery values for these samples were calculated in the range of 110-87%. In the third part, a new covalent organic framework was synthesized by a green and environmentally friendly method in an aqueous medium without using toxic solvents. Then, nanofibers with a core-shell structure of methyl acrylate and polyacrylonitrile copolymer were prepared by two concentric nozzles using the electrospinning method and were collected as a thin film. The synthesized COF was placed in the core of these nanofibers as the extraction phase and was used to extract molinate from an aqueous solution. In order to identify and measure this compound, an ion mobility spectrometer with a corona discharge source and thermal desorption injection port was used. The variables affecting the extraction process were optimized through the response surface methodology. Under optimal conditions, the linear range was 0.1-20 μg / L, the detection limit was 0.02 μg /L, and the relative standard deviation was less than 12%. The relative recovery value for aqueous samples was calculated in the range of 111-90.2%.

محمدتقي جعفري

محمد سراجي

علي اصغر انصافي، حسن قاضي عسكر، اكبر ملك پور