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51.
Mechanism of gallium discharge and ionization on a liquid gallium electrode in a fluoride-alkaline electrolyte was studied. The exchange currents, transfer coefficients in the cathodic and anodic processes, and the activation energy of the electrode process were determined. The conditions in which gallium(I) ion-intermediates are formed were analyzed. The coordination numbers of the gallium complexes formed in alkaline fluoride solutions were calculated.  相似文献   
52.
Data on the composition, structure, and properties (electronic and geometric structure, optical properties, thermodynamic functions) of mononuclear, polynuclear, and cluster complexes of bi-, tri-, tetra-, penta-, and hexavalent molybdenum are summarized and correlated. The thermodynamics, kinetics, and mechanisms of the ligand exchange, protonation deprotonation, redox reactions, and formation decomposition of cluster cores of molybdenum complexes in aqueous solutions are characterized.  相似文献   
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54.
It is shown that a Nb-based superconducting tunnel-junction detector can be used to record γ radiation in the energy range from 1 to 15 keV. The possibility of application of such detectors in Mössbauer spectroscopy is discussed. Prospects of application of tantalum absorbers are considered, in particular, the possibility of developing a cryogenic resonant detector for 181Ta.  相似文献   
55.
The first step in the research and development of detectors for 181Ta Mössbauer spectroscopy based on superconductive tunnel junctions (STJ) is taken. The idea of using β-tantalum as a trapping layer for the inactivation of the base electrode in a detector with the structure β-Ta/Nb/Al, AlO x /Al/Nb/NbN is successfully executed.  相似文献   
56.
This paper presents a mathematical model for the analysis of the stress-strain state of ice cover in the presence of a snow layer under dynamic loads. Numerical calculations were made using the model of indestructible ice, and the results were compared with experimental data.  相似文献   
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58.
Colloidal suspensions of hematite in contact with aqueous solutions of 50 mM alkali metal chloride electrolytes (NaCl, KCl, RbCl, CsCl) were investigated by cryogenic X-ray photoelectron spectroscopy (XPS) and electrophoretic mobility. Suspension pH values were varied from 2 to 11 in order to evaluate effects of positively- and negatively-charged hematite surfaces. XPS revealed coexisting cations and chloride ions both below and above the point of zero charge. Concentration profiles of adsorbed cations point to a Hofmeister series in the order of Na+ > K+ > Rb+  Cs+. Binding energies of photoelectrons emitted from electrolyte ions increased with pH at roughly 0.04 eV per pH unit. This shift was attributed to variations in the surface electric potential of hematite. This effect, compounded by rises in aliphatic carbon signals with pH, called for referencing of all spectra to the 530.0 eV oxide component of the hematite O1s spectrum. This departure from the traditional use of the external C 1s 285.0 eV peak is hereby proposed for cryogenic XPS studies of interfacial reactions involving hematite.  相似文献   
59.
The loss in the initial stage of energy relaxation in the absorber of a superconducting tunnel detector is considered using a simple spherical model that describes the escape of a cloud of secondary electrons (formed upon relaxation of the primary excitations caused by X-ray absorption) from the absorber. The foundations of this model are justified. Three situations dependent on the ratio of the detector thickness L and electron range R leading to different types of spectra are examined. The position, amplitude, and width of the line recorded by the detector are determined as well.  相似文献   
60.
A published ab initio-based potential energy surface and newly constructed dipole moment surface of acetylene have been used to compute vibrational band intensities. The line intensity calculations employed the variational nuclear motion code WAVR4 for computation of wave functions and energy levels, and a newly developed code DIPOLE4 for computation of dipole transitions. Owing to the high computational cost of J > 0 transitions using direct variational methods only J = 0 and J = 1 states and transitions have been computed variationally. The intensities of J > 1 transitions were extrapolated from J = 0 and J = 1 using Hönl–London coefficients. The resulting effective rotational constants B and transition intensities are compared with experimental data for the (3ν4 + ν5) combination band, the ν3 and the ν5 fundamental band. The prospects of using this procedure for extensive calculations of a hot line list, important for cool stars and extrasolar planets are discussed.  相似文献   
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