Abstract This paper applies a new approach to the identification of discourses, based on Multiple Correspondence Analysis (MCA), study discourse variation over time. The MCA keywords deals with major issue use identify discourses: allocation individual multiple discourses. Yet, as this demonstrates, also allows us observe in prevalence discourses texts patterns keyword co-occurrence. Metadata c...

Direct analysis of samples, regardless their origin, is desirable although for the majority of cases unfeasible on account of the complexity of the sample matrix, inadequate concentration of the target analytes, or even incompatibility with the detector. In these cases, a sample pretreatment step is required for interference removal and analytes separation/preconcentration. Despite valuable adv...

Authors are requested to select key words from the following list. You may use plurals and adjectives for combinations like absolute pupillary response, centrifugal optic nerve, inter blobs, etc. If key words are needed which do not appear in this list, please underline them. For animal classification the Latin nomenclature should be used. p-mechanism A-scan a-wave aberration absolute absorptio...

Triazole fungicides are systemic fungicides applied to protect crops from fungus infections. Its use must be controlled due to the potential harmful effects in environment and human health. Before determination with a chromatographic system, analyte must be isolated and preconcentrated with an extraction step. This review presents the most used microextraction techniques for those compounds in ...

Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environme...

2 Headspace sampling for gas chromatographic (GC) analysis has many advantages, the most important of which is the elimination of many interferences from the sample matrix. In addition to the standard methods for headspace sampling, the technique of solid-phase microextraction (SPME) has found wide acceptance because it is simple and inexpensive. More recently, single-drop microextraction (SDME...

background and objectives: furfural (f) and hydroxymethyl furfural (hmf) are cyclic aldehydes, which are formed during the heat processing of foods. these chemical contaminants have received much attention due to their suspected health hazards and heat damage indicators. the aim of the present study was extraction and determination of f and hmf in baby-foods using dispersive liquid-liquid micro...