Trace quantities of laser ablated organic polymers were analyzed by using commercial capillary column gas chromatography/mass spectrometry; the instrument was modified so that the iaser ablation products could be introduced into the capillary column directly and the constituents of each peak in the chromatogram were identified by using a mass spectrometer. The present study takes advantage of t...

Because of the high efficacy of existing nitrates, alternative dosage formulations have been developed rather than new compounds. These new formulations challenge the analyst to develop analytical methods with lower sensitivity and higher precision. Isosorbide dinitrate is analysed in the presence of its major metabolites isosorbide 2-mononitrate and isosorbide 5-mononitrate. The present method...

In this study, dC values of six cocaine samples were identified and classified using a single quadrupole mass spectrometer and an isotope ratio mass spectrometry (IRMS) as simultaneous gas chromatography detectors. Our instrument modification is simple to use and is useful (i) when the sample is of limited size or can only be injected once, (ii) to help identify peaks in a complicated IRMS chro...

This paper describes a new technique for removing the background level from digital images produced in comprehensive two-dimensional gas chromatography (GCxGC). Background removal is an important first step in the larger problem of quantitative analysis. The approach estimates the background level across the chromatographic image based on structural and statistical properties of GCxGC data. The...

Abstract. Environmental samples typically contain hundreds or thousands of unique organic compounds, and even minor components may provide valuable insight into their sources transformations. To understand atmospheric processes, individual are frequently identified quantified using gas chromatography–mass spectrometry. However, due to the complexity variable nature such data, data reduction is ...

The presented strategy of automatic baseline detection in chromatograms combines fuzzy logic and neural network approaches. It is based on a verbal description of a baseline referring to a 2D image of a chromatogram instead of a data vector. Baselines are expected to touch data points on the lower border of the chromatogram forming a mainly horizontal and straight line. That description has bee...

conclusions results have shown that a. spicigera eo before and after flowering has antioxidant properties and therefore can be used in combination with other preservatives to protect food materials against a variety of oxidative systems. background essential oils (eo), also called volatile odoriferous oil, are aromatic oily liquids extracted from different parts of plants. in general, the const...

The current study was designed to conduct the physicochemical, phytochemical and gas chromatography- mass spectrometry analysis of Chenopodium album Stellaria media L. Methanolic extract dried leaves prepared subsequently fractionated using different solvents like hexane, chloroform, ethyl acetate. Obtained plant fractions were analyzed for presence secondary metabolites screening methods. Furt...