Theoretical assessments on the interaction between amino acids and g‒Mg3N2 monolayer: dispersion corrected DFT and DFT-MD simulations

The interaction of a few amino acids (AAs) with graphene-like magnesium nitride (g‒Mg3N2) monolayer has been investigated with density functional theory (DFT) simulations. The Mg site was found to cause...

Structural Properties and ELNES of Polycrystalline and Nanoporous Mg3N2

Nanoporous, high-purity magnesium nitride (Mg3N2) was synthesized with a liquid ammonia-based process, for potential applications in optoelectronics, gas separation and catalysis, since these applications require high material purity and crystallinity, which has seldom been demonstrated in the past. One way to evaluate the degree of crystalline near-range order and atomic environment is electron energy-loss spectroscopy (EELS) in a transmission electron microscope. However, there are hardly any data on Mg3N2, which makes identification of electron energy-loss near-edge structure (ELNES) features difficult. Therefore, we have studied nanoporous Mg3N2 with EELS in detail in comparison to EELS spectra of bulk Mg3N2, which was analyzed as a reference material. The N-K and Mg-K edges of both materials are similar. Despite having the same crystal structure, however, there are differences in fine-structural features, such as shifts and absences of peaks in the N-K and Mg-K edges of nanoporous Mg3N2. These differences in ELNES are attributed to coordination changes in nanoporous Mg3N2 caused by the significantly smaller crystallite size of 2–6 nm compared to the larger (25–125 nm) crystal size in a bulk material.

Liquid-ammonia synthesis of microporous Mg3N2showing intense red-light emission

Magnesium nitride (Mg3N2) is preparedvialyotropic phases with liquid ammonia (lq-NH3). To avoid oxide contamination, the synthesis was performed in the absence of any oxygen source (e.g., solvents, starting materials and surfactants).

Complex desulfurization and degassing of hot metal with magnesium

The aim of the work is a theoretical and experimental study of the behavior of oxygen, hydrogen and nitrogen in iron during desulfurization with its granulated magnesium. A computational and analytical assessment of the formation and floating of gas bubbles during the introduction of dispersed magnesium into a metal melt in an argon jet is performed. It has been established by calculation that when dispersed magnesium is introduced into the cast iron in an argon jet, through a lance with a nozzle diameter of 7 mm to a depth of 3 m, argon bubbles with a diameter of 25 mm are formed. The thermodynamic probability of the processes of interaction of magnesium with oxygen, nitrogen and hydrogen during desulfurization of cast iron has been established. It has been established that the processes of desulfurization and deoxidation of iron occur throughout the entire range of pressures under study, and the formation of magnesium nitride is possible only with an excess pressure in the gas-metal system at a depth of molten iron more than 1.4 meters. Experiments in industrial conditions revealed the features of the removal of oxygen, nitrogen and hydrogen from cast iron during desulfurization of the melt with dispersed magnesium in a stream of various carrier gases. It was established experimentally that the type of carrier gas has a decisive influence on the by-pass degassing of the iron during its desulfurization by injecting granular magnesium. When using nitrogen or argon as a carrier gas, the hydrogen content in cast iron is reduced by 50-70%.

Mechanism for anomalous luminescence behaviour of Eu2+-doped red-emitting magnesium nitride phosphors

A series of novel red-emitting phosphors Mg3−xN2:xEu2+ (0 ≤ x ≤ 0.08) were successfully synthesized by solid-state reactions at low temperature.