Synchronization of Separation and Detection

A major problem to be solved is synchronization of the continuous sample flow from the chromato-graphic equipment and the scan time required for taking an ESR spectrum. This subject has already been tackled by a number of authors. However, problems regarding signal separation and measurement sensitivity remain. A typical ESR scanning time is one minute for a spectrum and this may be in conflict with the elution time of a single fraction from a HPLC column. Since complete chromatograms usually take some 8-15 min, single fractions are likely to take less than a minute to elute so no constant conditions can be expected in the sample cuvette while a spectrum is running. Simply stopping the flow for the time of recording a spectrum may result in local diffusion, causing a loss of resolution in the separation step, so this approach is not recommended. Pulsed short-time spectra (FT-spectroscopy) are very sophisticated requiring a much more complicated instrumentation, so the 'cw' (continuous wave) technique still remains the current standard method.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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