Determination of ammonium in natural water using a quinoline-based -dialdehyde fluorescent reagent with visible excitation wavelength.

In this paper, a novel and stable fluorescent reagent, quinoline-2,3-dicarbaldehyde (QDA), is synthesized as a probe to detect ammonium in natural water. Ammonium reacts with QDA in the presence of SO and Ca to form a fluorescence product, which has maximum excitation and emission wavelengths at 429 nm and 518 nm. The concentration of reagents, the reaction temperature, the reaction time, and the pH in the final solution are investigated and optimized.

Organic synthesis of fixed CO using nitrogen as a nucleophilic center.

In this review, recent progress in the application of CO2 as an electrophilic reagent and nitrogen as a nucleophilic center under different catalytic conditions in organic synthesis is summarized. The used catalytic methods in the reactions of CO2 and nitrogen are classified as metal catalysis, metal-free catalysis, photocatalysis and electrocatalysis. Various catalytic conditions have been used to solve the problems of thermodynamic properties and stability of CO2.