Modeling the effect of temperature on solid-phase microextraction of volatile organic compounds from air by polydimethylsiloxane coating using finite element analysis.

A development of analytical methods based on solid-phase microextraction (SPME) is a very time- and labor-consuming task. The finite element methods have found a wide application in SPME modeling for faster and more accurate optimization of analytical methods. In this work, a computational model for predicting the effect of temperature on extraction of VOCs from air onto SPME coating based on polydimethylsiloxane (PDMS) has been developed using COMSOL Multiphysics® (CMP) software.

Effects of oxidant and catalyst on the transformation products of rocket fuel 1,1-dimethylhydrazine in water and soil.

Existing methods for cleanup of wastewaters and soils polluted with the extremely toxic rocket fuel unsymmetrical dimethylhydrazine (UDMH) are mainly based on the treatment with various oxidative reagents. Until now, the assessment of their effectiveness was based on the residual content of UDMH and did not take into account the possibility of the formation of a large number of potentially dangerous nitrogen-containing transformation products (TPs). In this study, using the recently developed approach based on high-resolution Orbitrap mass spectrometry, the comprehensive characterization of UDMH TPs formed by the action of air oxygen and different oxidants (Fenton's reagent, KMnO, HOCl, HO in the presence of Cu and [Fe (EDTA)] catalysts) typically used to detoxify spill sites was performed.

Quantification of transformation products of rocket fuel unsymmetrical dimethylhydrazine in soils using SPME and GC-MS.

Determination of transformation products (TPs) of rocket fuel unsymmetrical dimethylhydrazine (UDMH) in soil is highly important for environmental impact assessment of the launches of heavy space rockets from Kazakhstan, Russia, China and India. The method based on headspace solid-phase microextraction (HS SPME) and gas chromatography-mass spectrometry is advantageous over other known methods due to greater simplicity and cost efficiency. However, accurate quantification of these analytes using HS SPME is limited by the matrix effect.

Determination of 1-methyl-1H-1,2,4-triazole in soils contaminated by rocket fuel using solid-phase microextraction, isotope dilution and gas chromatography-mass spectrometry.

Environmental monitoring of Central Kazakhstan territories where heavy space booster rockets land requires fast, efficient, and inexpensive analytical methods. The goal of this study was to develop a method for quantitation of the most stable transformation product of rocket fuel, i.e.