N-methylmorpholine (NMM) can be detected by a variety of methods, including:

Ultraviolet-Visible Spectrum: NMM absorbs light in the ultraviolet-visible (UV-Vis) region of the electromagnetic spectrum. The absorbance of NMM can be used to quantify the concentration of NMM in solution.

Infrared Spectrum: NMM has a characteristic infrared (IR) spectrum. Infrared spectroscopy of NMMs can be used to identify NMMs and quantify the concentration of NMMs in solution.

NMR Spectrum: NMM has a characteristic nuclear magnetic resonance (NMR) spectrum. The NMR spectrum of NMM can be used to identify NMM and quantify the concentration of NMM in solution.

Mass spectrometry: NMM can be detected by mass spectrometry. Mass spectra of NMMs can be used to identify NMMs and quantify the concentration of NMMs in solution.

Chromatography: NMM can be separated and quantified by chromatography. The most common types of chromatography used to detect NMMs are gas chromatography (GC) and liquid chromatography (LC).

The method used to detect NMM will depend on the specific application. For example, UV-Vis spectroscopy is a common method for detecting NMMs in solution, while GC and LC are common methods for detecting NMMs in environmental samples.