Solvothermal reactions of TaCl5 with LiNH2 in benzene result in nanocrystalline Ta3N5 at 500 or 550 degrees C. The approximately 25 nm Ta3N5 particles have a band gap of 2.08-2.10 eV. The same reactions in mesitylene resulted in a higher crystallization temperature and large amounts of carbon incorporation due to solvent decomposition. Reactions of Ta(NMe2)5 with LiNH2 under the same conditions resulted in TaN. Rocksalt-type MN phases are obtained for Zr, Hf, or Nb when their chlorides (ZrCl4, HfCl4, or NbCl5) or dialkylamides (M(NEtMe)4, M = Zr, Hf) are reacted with LiNH2 under similar conditions. With the amides, there is some evidence for nitrogen-rich compositions (HfN >1), and carbon is incorporated into the products through pyrolysis of the dialkylamide groups.

Transition metal chlorides are reacted with lithium amide or ammonia under solvothermal conditions in benzene at temperatures up to 550 degrees C. The products are metal nitrides with particle sizes of a few nm. VN, NbN, CrN, MoN and WN form with a cubic rocksalt-type structure, whilst Ta(3)N(5) adopts the known orthorhombic structure. Products often contain carbon due to solvent decomposition, the carbon content is higher when ammonia is the nitrogen source, and varied to some extent from metal to metal. Analytical data shows nitrogen-deficient carbonitride compositions. Most samples crystallise with partially aggregated, regular crystallites. Some crystallise with a nanorod morphology and this was most pronounced in Ta(3)N(5), which forms high aspect ratio, single crystal nanorods when synthesised with ammonia.

Results of the investigation of the reactions of GaCl3, InCl3 and InI3 with LiNH2 under solvothermal conditions in benzene, which lead to metal nitrides, are reported. GaN is obtained as a cubic phase or as a mixture of cubic and hexagonal phases, depending on temperature. The effect of the addition of surfactants on the formation of GaN was explored. InN products were always contaminated with indium metal, even at low reaction temperatures. The addition of excess LiNH2 or the use of InI3 instead of InCl3 gave products with less In metal

In this work, a computational study on two-dimensional forced convection inside a volumetric solar collector based on a nanofluid with water and nanocarbon horns is carried out in steady state regime. A surface heat transfer from the upper wall of the solar collector toward the external ambient is present. The analysis is accomplished with governing equations assuming the single-phase flow model for the nanofluid mixture. The evaluation of heat transfer in the participating media due to the local absorption of nanoparticles is obtained employing the non-grey discrete ordinates method. The finite volume method is employed to find the solution and the simulations are obtained using ANSYS-FLUENT code. The analysis is accomplished to estimate the solar collector behaviors as a function of the inclination angle under different conditions in summer and winter regimes for residential use site in Aversa (Italy). The analysis allows to evaluate the thermal and fluid dynamic behaviors of the solar collector with an inclination angle from 0 to 90 degrees. Temperature and velocity profiles as well as temperature fields inside the channel are reported for different inclination angles, solar radiations and nanoparticle volumetric concentrations.