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When the rare earth mononitrides (RENs) first burst onto the scientific scene in the middle of last century, there were feverish dreams that their strong magnetic moment would afford a wide range of applications. For decades research was frustrated by poor stoichiometry and the ready reaction of the materials in ambient conditions, and only recently have these impediments finally been overcome by advances in thin film fabrication with ultra-high vacuum based growth technology. Currently, the field of research into the RENs is growing rapidly, motivated by spintronic structures and devices to advance and support quantum and superconducting computing. The technology depends critically on the formation of REN thin films, for which the optimum growth is to form the nitrides within an atmosphere of pure molecular nitrogen. The process is surprisingly efficient, and such catalytic activity of a clean RE surface opened much more widely important implications. Recently, we have demonstrated that the novel and easy breaking of molecular nitrogen gas under mild conditions on a clean lanthanide surface can be used to ammonia (NH3) at ambient temperature and low pressure, opening the door to a promising new class of catalyst that is not bound by the scaling relations of industrial transition metal-based catalysts.

The current work implemented in DSMC vibrational excited levels of N2 and transitions between the levels as well as the dissociation of nitrogen molecules from different levels. Results show that due to insufficient collisions, the flow around a sphere at 70/75 km altitudes has a high degree of nonequilibrium in the vibrational mode where the ground level is separated from the higher levels. The continuum-level calculation results are different from the work of Candler and the nonequilibrium profile predicted by the discrete-level calculation is also different. [ABSTRACT FROM AUTHOR]

Using the X-ray photoelectron spectroscopy, a comparative analysis of the chemical state and electronic structure of carbon nanotubes (CNTs), which were doped using various approaches was made. Doping of CNTs was carried out directly in the course of their synthesis by using a nitrogen-containing carbon precursor, and by post-synthesis treatment of undoped CNTs with a beam of nitrogen ions with an average energy of∼5 keV. The results obtained showed that the doping of CNTs during synthesis provides a dopant concentration of no more than 3 % at. At the same time, a certain part of nitrogen atoms is embedded in the structure of CNT walls in the form of various electrically active defects, the rest of the nitrogen is represented by molecular nitrogen, which is present in the interwall space of multilayer CNTs, as well as in their internal cavities. Doping of CNTs by treatment with a nitrogen ion beam provides a higher degree of doping (∼ 6% at.). In this case, all nitrogen is incorporated into the structure of CNT walls in the form of electrically active defects in the graphene structure. It is shown that the presence of a large number of oxygen-containing functional groups is observed on the CNT surface after irradiation with nitrogen ions. The formation of such groups is possible both during the ion treatment and during the subsequent storage of irradiated samples in the atmosphere. Such groups are also electrically active sites on the surface of carbon nanotubes. The results obtained indicate that the doping of CNTs with nitrogen using ion irradiation is an effective method for modifying their electronic structure. CNTs doped with nitrogen using ion irradiation showed a more than twofold increase in specific capacity compared to CNTs doped during synthesis. [ABSTRACT FROM AUTHOR]

Using phase-shaped millijoule 1030-nm femtosecond pulses generating a filament in a cell filled with N2, we obtain intense forward UV emission between vibrational manifolds of B2Σ and X2Σ states of N2+ for optimal pulse sequences. The effect is tentatively ascribed to wave-mixing between intense NIR pulses and weak supercontinuum components, resonant to the UV transitions, whereby a non-instantaneous nonlinear susceptibility is linked to rotational coherence in ions. [ABSTRACT FROM AUTHOR]

The tangent-slab approximation is implemented in User Defined Functions of the ANSYS Fluent flow-solver to compute coupled flowfield and radiation phenomena in the flow around a reentry body. The flow around the FIRE II capsule at an altitude of 84.6 km, which enters the Earth atmosphere at a superorbital velocity, is considered to test the functions developed in the study. The numerical results of the computations with and without the flowfield–radiation coupling show that there is a noticeable change in the radiative energy source term if this coupling is taken into account, while the distribution of the vibrational temperature of molecular nitrogen is only slightly affected. The effect of the flowfield–radiation coupling on the surface radiative heat flux at the stagnation point is assessed at about 20%. [ABSTRACT FROM AUTHOR]

In recent years, the atmosphere pressure plasma jet was significant point in plasma physics because of its application in medicine as well as biomedical; therefore, the needing for experimental plasma devices was important to produce non-thermal atmospheric pressure plasmas. In present study, double ring electrodes configuration worked in argon flow to plasma plume employed. The impact of the tube diameter on production efficiency of reactive species was predicted, using three different values of tube diameter of Pyrex tube (1.9, 3, and 6 mm). A sinusoidal AC voltage of 15 kV with 6 kHz employed to ignite the plasma operations. Optical emission spectroscopy (OES) was a simple method to understand the plasma diagnostic such as emission intensity. In addition, OES used to detect the active species. Both the ignition and emission intensity of the plasma in the capillary tube depend on tube diameter. Results showed that the tube diameter play a significant role in discharge ignition and sustaining voltage. The time of breakdown of argon gas to generate plasma increased if the tube diameter increased. The peak intensity of OH, (O II), (Ar II) and excited molecular nitrogen (N2) increased more if the tube diameter decreased. [ABSTRACT FROM AUTHOR]

The relevance of the effective organization of expansion-supply and reduction of nitrogen oxides of carbon to molecular nitrogen and gasification to carbon oxides are discussed in the paper. The experimental technique and equipment, calculated and experimental data on the rate and composition of the chemistry-reactions are also presented. The results of the calculation and the development of the conceptual project for dust supplying Ekibastuz coal of high concentration with a shift of combustion processes Ekibastuz CHP to reduce nitrogen oxides in a reconstruction of the boiler are presented. [ABSTRACT FROM AUTHOR]