1. Sugars present in nectar secreted by twelve species were separated on paper chromatograms, and quantitative determinations of the amounts of glucose and fructose were made. The total sugar content of each sample was measured with a refractometer. 2. The proportions of glucose and fructose varied greatly in nectar from different species. 3. For any one species, the proportions of the differen...

UNLABELLED Chromaligner is a tool for chromatogram alignment to align retention time for chromatographic methods coupled to spectrophotometers such as high performance liquid chromatography and capillary electrophoresis for metabolomics works. Chromaligner resolves peak shifts by a constrained chromatogram alignment. For a collection of chromatograms and a set of defined peaks, Chromaligner ali...