Features of Studying Atomic Hydrogen – Metal Systems

2019 ◽  
pp. 62-87
Author(s):  
D. V. Schur ◽  
S. Yu. Zaginaichenko ◽  
A. Veziroglu ◽  
T. N. Veziroglu ◽  
A. D. Zolotarenko ◽  
...  
Keyword(s):  
Atomic Hydrogen ◽  
Diffusion Processes ◽  
Hydrogen Plasma ◽  
Kinetic Method ◽  
Experimental Studies ◽  
Heterogeneous Reactions ◽  
Metal Foil ◽  
Hydrogen Energy ◽  
Hydrogen Atoms ◽  
Electrodeless Discharge

All the main areas of energy development suggest or are already implementing the use of metal-hydrogen systems. For nuclear energy, this is associated with the creation of thermostable moderators and special-purpose construction materials, for thermonuclear energy, with the behavior of the so-called first wall of fusion reactors, for hydrogen energy — storage, transportation and extraction of hydrogen. Hydrogen is the most effective moderator of fast and thermal neutrons, especially at high volumetric concentrations of hydrogen atoms in the material, i.e. at a high value of the ratio of the number of hydrogen atoms to the number of metal atoms, taking into account the heat resistance of the hydride. This paper discusses the modern methods of experimental studies of heterogeneous reactions, the topochemistry of metal – hydrogen reactions, the dependence of the interaction rate on pressure and temperature, models of surface processes occurring during the interaction of hydrogen with metal.  Methods for determining the probability of adsorption of hydrogen on a metal surface, methods for measuring the activation energy of dissociation of a hydrogen molecule on a surface are also discussed. The paper describes the fea-tures of the preparation of the reactor, experimental samples and the method of their study in the study of atomic hydrogen-metal systems, the method of plasma-chemical thermogravimetry used to study heterogeneous reactions occurring in a hydrogen plasma electrodeless discharge. In order to study the mechanism of interaction of hydrogen with hydride-forming metals, a kinetic method of research is proposed. The essence of the kinetic method is that the elimination of the limiting influence of surface and diffusion processes on the rate of hydride formation using atomic hydrogen and metal foil makes it possible to directly record the formation of the corresponding phases using hydro-gen-metal kinetic curves, and also study the effect of various parameters on the rate of interaction and the formation of hydride phases.  

scholarly journals FORMATION OF LIGHT IMPURITIES IN A HYDROGEN PLASMA AT INITIAL STAGE OF A DISCHARGE

2019 ◽  
pp. 110-112
Author(s):  
V.B. Yuferov ◽  
E.I. Skibenko ◽  
V.I. Tkachov ◽  
V.V. Katrechko ◽  
A.S. Svichkar
Keyword(s):  
Atomic Hydrogen ◽  
Molecular Hydrogen ◽  
Hydrogen Plasma ◽  
Hydrogen Ions ◽  
Hydrogen Atoms ◽  
Impurity Atoms ◽  
Radiation Fluxes ◽  
Start Up ◽  
Initial Stage ◽  
Light Impurities

Analyzing the dynamics of density for atomic and molecular hydrogen ions, the values of atomic hydrogen and UV radiation fluxes to the walls of the plasma chamber were obtained, resulting in light impurities of carbon and oxygen at plasma start-up during the process of desorption from the walls under irradiation. The fluxes of impurity atoms associated with the fluxes of photons and hydrogen atoms in a discharge are determined. Recommendations are given to reduce the amount of impurities at the initial stage of discharge.

Diffusion processes and interactions of hydrogen atoms in Pd

1995 ◽  
Vol 205 (2) ◽  
pp. 163-168 ◽  
Author(s):  
Byung-Sub Kang ◽  
Ki-Soo Sohn
Keyword(s):  
Diffusion Processes ◽  
Hydrogen Atoms

scholarly journals PARAMETERS OF HYDROGEN PLASMA STREAMS IN QSPA-M AND THEIR DEPENDENCE ON EXTERNAL MAGNETIC FIELD

2021 ◽  
pp. 61-64
Author(s):  
M.S. Ladygina ◽  
Yu.V. Petrov ◽  
D.V. Yeliseev ◽  
V.A. Makhlai ◽  
N.V. Kulik ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electron Density ◽  
Hydrogen Plasma ◽  
Experimental Studies ◽  
Optical Emission ◽  
Plasma Electron ◽  
Plasma Stream ◽  
Visible Radiation ◽  
Order Of Magnitude ◽  
Plasma Electron Density

Present experimental studies are aimed at analysis of hydrogen plasma stream parameters in various working regimes of QSPA-M operation. Temporal distributions of plasma electron density are reconstructed with optical emission spectroscopy. The magnetic field influence on plasma streams parameters is analyzed. It is shown that in regimes with additional magnetic field the plasma electron density increases by an order of magnitude in comparison with a density value without magnetic field. The plasma velocity and energy density parameters as well as their temporal behaviors were estimatedin different operating regimes of QSPA-M facility. Features of plasma visible radiation were analyzed. This information is important for QSPA-M applications in experiments on interaction of powerful plasma streams with material surfaces.

scholarly journals Сечения образования ионов He-=SUP=-+-=/SUP=- в различных электронных состояниях при столкновениях ионов He-=SUP=-2+-=/SUP=- с атомами водорода

2020 ◽  
Vol 90 (6) ◽  
pp. 895
Author(s):  
А.А. Басалаев ◽  
В.В. Кузьмичев ◽  
М.Н. Панов ◽  
О.В. Смирнов
Keyword(s):  
Kinetic Energy ◽  
Electron Capture ◽  
Cross Sections ◽  
Atomic Hydrogen ◽  
Precision Measurements ◽  
Capture Cross ◽  
Hydrogen Atoms ◽  
Hydrogen Target ◽  
Degree Of Dissociation ◽  
Capture Cross Sections

Using collision spectroscopy based on precision measurements of the kinetic energy of projectile ions that capture an electron, we measured the state selective electron capture cross sections of formation of He^+(n) ions at collision 3^He^{2 +} ions with an energy of E = 1.4-10 keV/a.m.u. with hydrogen atoms. The atomic hydrogen target with a degree of dissociation 78% at a temperature of tungsten dissociation cell 2180K has been made.

Photodissociation of H2 near Threshold Energies

1970 ◽  
Vol 25 (2) ◽  
pp. 237-242 ◽  
Author(s):  
F. J. Comes ◽  
U. Wenning
Keyword(s):  
Electric Field ◽  
Cross Section ◽  
Configuration Interaction ◽  
Atomic Hydrogen ◽  
Molecular Hydrogen ◽  
Hydrogen Atoms ◽  
Dissociation Cross Section ◽  
Excited Molecules ◽  
Threshold Energies ◽  
Near Threshold

Abstract Measurements of the atomic hydrogen fluorescence (Lyα) yield important information on the dissociation behavior of molecular hydrogen under photon impact. Under certain assumptions the dissociation cross section of the molecule can be deduced from such experiments. By applying an appropriate electric field in the observation region those dissociations leading to the formation of metastable hydrogen atoms can be quantitatively determined. This information opens the possibility to describe the predissociation of the excited H2-molecules in the C-, D-and B″-states. The experiments show that the excited molecules in these particular states dissociate into H(1S) and H(2S) by configuration interaction with the B′-state.

Stationary inverted Lyman populations and free-free and bound-free emission of lower-energy state hydride ion formed by an exothermic catalytic reaction of atomic hydrogen and certain group I catalysts

Open Physics ◽  
2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Randell Mills ◽  
William Good ◽  
Peter Jansson ◽  
Jiliang He
Keyword(s):  
Catalytic Reaction ◽  
Atomic Hydrogen ◽  
Microwave Plasma ◽  
Energy State ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Hydrogen Atoms ◽  
Hydride Ion ◽  
Group I ◽  
Excess Power

AbstractRb+ to Rb2+ and 2K+ to K + K2+ each provide a reaction with a net enthalpy equal to the potential energy of atomic hydrogen. The presence of these gaseous ions with thermally dissociated hydrogen formed a plasma having strong VUV emission with a stationary inverted Lyman population. Significant Balmer α line broadening of 18 and 9 eV was observed from a rt-plasma of hydrogen with KNO3, and RbNO3, respectively, compared to 3 eV from a hydrogen microwave plasma. The reaction was exothermic since excess power of about 20 mW/cc was measured by Calvet calorimetry. We propose an energetic catalytic reaction involving a resonance energy transfer between hydrogen atoms and Rb+ or 2K+ to form a very stable novel hydride ion. Its predicted binding energy of 3.0471 eV with the fine structure was observed at 4071 Å, and its predicted bound-free hyperfine structure lines matched those observed for about 40 lines to within.01 percent. Characteristic emission from each catalyst was observed. This catalytic reaction may pump a CW HI laser.

Curve-crossing collisions of excited lead atoms in flames

1981 ◽  
Vol 376 (1767) ◽  
pp. 545-564 ◽  
Keyword(s):  
Rate Constant ◽  
Atomic Hydrogen ◽  
Negative Temperature Coefficient ◽  
Negative Temperature ◽  
Model Systems ◽  
Attractive Potential ◽  
Hydrogen Atoms ◽  
Lennard Jones ◽  
Increasing Temperature ◽  
Curve Crossing

Lead atoms, present as a trace additive in a series of premixed H 2 –N 2 –O 2 flames, were excited to the 7 3 P o 1 state by 405.8 nm radiation from a nitrogen-pumped dye laser. Rate constants for spin-orbit relaxation to the 7 3 P o 0 state were obtained separately for collisions with atomic hydrogen and for collisions with the bulk flame gas, by measuring the relative intensities of fluorescence at 364.0 and 368.3 nm as a function of distance from the reaction zone in each flame. For hydrogen atoms the rate constant is typically 1 x 10 -9 cm 3 molecule -1 s -1 , decreasing with increasing temperature; for the bulk flame gas the rate constant is typically 1 x 10 -11 cm 3 molecule -1 s -1 , increasing with increasing temperature. Numerical calculations for model systems, with the use of Morse and Lennard-Jones potentials to describe the interaction of the colliding species, show that the negative temperature coefficient found for atomic hydrogen can be attributed to the crossing of attractive potential curves, corresponding to bound excited states of PbH.

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