Improvement of the analytical possibilities of dual-column ion-chromatography

Summary Dual-column ion-chromatography is an effective method for determining organic and inorganic ions, especially anions, in different natural and industrial objects. In a number of cases, however, some problems occur limiting its analytical possibilities. These problems are connected with the limited choice of eluents and sorbents, with insufficient selectivity for some objects, unsatisfactory rapidity of determination, and with the occurrence of water dips and system peaks in the chromatogram. In order to solve these problems and improve the analytical possibilities of dualcolumn ion-chromatography it is suggested to use aminoacid eluents, stepwise elution and complex formation of the ions being determined and eluted.

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Verbesserung der analytischen Möglichkeiten der Doppelsäulen-Ionen-Chromatographie

     

Variations in the total electron content of the ionosphere during preparation of earthquakes

The morphological features in the deviations of the total electron content (TEC) of the ionosphere from the background undisturbed state as possible precursors of the earthquake of January 12, 2010 (21:53 UT (16:53 LT), 18.46° N, 72.5° W, 7.0 M) in Haiti are analyzed. To identify these features, global and regional differential TEC maps based on global 2-h TEC maps provided by NASA in the IONEX format were plotted. For the considered earthquake, long-lived disturbances, presumably of seismic origin, were localized in the near-epicenter area and were accompanied by similar effects in the magnetoconjugate region. Both decreases and increases in the local TEC over the period from 22 UT of January 10 to 08 UT of January 12, 2010 were observed. The horizontal dimensions of the anomalies were ∼40° in longitude and ∼20° in latitude, with the magnitude of TEC disturbances reaching ∼40% relative to the background near the epicenter and more than 50% in the magnetoconjugate area. No significant geomagnetic disturbances within January 1–12, 2010 were observed, i.e., the detected TEC anomalies were manifestations of interplay between processes in the lithosphere-atmosphere-ionosphere system.