The Effect of In Situ Synthesis of MgO Nanoparticles on the Thermal Properties of Ternary Nitrate

The multiple eutectic nitrates with a low melting point are widely used in the field of solar thermal utilization due to their good thermophysical properties. The addition of nanoparticles can improve the heat transfer and heat storage performance of nitrate. This article explored the effect of MgO nanoparticles on the thermal properties of ternary eutectic nitrates. As a result of the decomposition reaction of the Mg(OH)2 precursor at high temperature, MgO nanoparticles were synthesized in situ in the LiNO3–NaNO3–KNO3 ternary eutectic nitrate system. XRD and Raman results showed that MgO nanoparticles were successfully synthesized in situ in the ternary nitrate system. SEM and EDS results showed no obvious agglomeration. The specific heat capacity of the modified salt is significantly increased. When the content of MgO nanoparticles is 2 wt %, the specific heat of the modified salt in the solid phase and the specific heat in the liquid phase increased by 51.54% and 44.50%, respectively. The heat transfer performance of the modified salt is also significantly improved. When the content of MgO nanoparticles is 5 wt %, the thermal diffusion coefficient of the modified salt is increased by 39.3%. This study also discussed the enhancement mechanism of the specific heat capacity of the molten salt by the nanoparticles mainly due to the higher specific surface energy of MgO and the semi-solid layer that formed between the MgO nanoparticles and the molten salt.

Enhanced interfacial property of carbon fiber reinforced epoxy composite based on carbon fiber treated by supercritical water/nitrate system

Carbon fibers were surface treated with supercritical water/nitrate system to improve the interfacial adhesion of the carbon fiber/epoxy composite. The surface chemistry analysis showed that oxygen functional groups on the surface of the carbon fibers increased after treatment, which were mainly carbonyl and carboxyl groups. The surface microstructure observation indicated that the treatment obviously increased the surface roughness of the carbon fibers. Surface energy of the treated carbon fibers also increased. The increased functional groups, surface roughness and surface energy were beneficial to enhance the interfacial adhesion of the carbon fiber/epoxy composite. Compared with the untreated carbon fibers, the strength loss of the treated carbon fibers was less than 3% and the other mechanical properties were almost unchanged. The caclulated interfacial fracture energy and the interfacial shear strength of the treated carbon fiber/epoxy composite were enhanced by 19% and 29%, respectively, compared with the untreated carbon fiber/epoxy composite. In summary, supercritical water/nitrate treatment is a potential method for changing the inert surface of carbon fibers to improve the interfacial adhesion between carbon fibers and matrix.

NHPI and ferric nitrate: a mild and selective system for aerobic oxidation of benzylic methylenes

An NHPI and ferric nitrate system was developed for efficient oxidation of benzylic methylenes with 1 atm of oxygen at 25 °C, providing up to 97% yield.

"321" Incident Iron Ions Characteristics and Catalytic Mechanism of Thinking

Compatibilityand safety systems research and production equipment itself explosives mixedvehicle technology between the establishment and development of the explosionmechanism of explosive accidents and prevent the occurrence of accidentalexplosion of explosives to achieve disaster prevention and reduction, to ensurethe safety of personnel and minimize property damage. Research explosives mixedvehicle production equipment commonly used in metal and alloys in aqueousammonium nitrate system compatibility, especially at higher temperatures and avariety of elements, such as the case of explosives from the synergies toaccelerate the reaction conditions, choose good compatibility the materials toimprove the production of mixed explosive nature of car safety, to solve theproduction of explosives explosion problem.