scholarly journals INTERDIFFUSION OF Mo AND W UNDER IN-PILE IRRADIATION CONDITIONS

2021 ◽  
Vol 247 ◽  
pp. 09022
Author(s):  
A.S. Ivanov ◽  
V.A. Churin
Keyword(s):  
Experimental Data ◽  
Concentration Dependence ◽  
Fast Neutrons ◽  
Approximation Procedure ◽  
Reactor Radiation ◽  
Thermally Activated ◽  
Diffusion Effects ◽  
Interdiffusion Coefficients ◽  
And Tungsten

The study has established that reactor radiation leads to a significant increase of interdiffusion coefficients in a Mo-W alloy compared to thermally activated diffusion at temperatures of ~1500°С. Furthermore, a weakening of their concentration dependence is observed. The approximation procedure developed in this work allowed approximating experimental data for each sample using variation of only one parameter. It has been demonstrated that the interaction of molybdenum and tungsten nuclei with fast neutrons as well as with hard gamma quanta may cause the observed diffusion effects.

TEMPERATURE DEPENDENCE BEHAVIOR OF ELECTRICAL RESISTIVITY IN NOBLE METALS AT LOW TEMPERATURES

2014 ◽  
Vol 5 (3) ◽  
pp. 982-992 ◽  
Author(s):  
M AL-Jalali
Keyword(s):  
Experimental Data ◽  
Electrical Resistivity ◽  
Temperature Dependence ◽  
Concentration Dependence ◽  
Low Temperatures ◽  
Noble Metals ◽  
Phonon Scattering ◽  
Theoretical Models ◽  
Residual Resistivity ◽  
Electron Phonon Scattering

Resistivity temperature – dependence and residual resistivity concentration-dependence in pure noble metals(Cu, Ag, Au) have been studied at low temperatures. Dominations of electron – dislocation and impurity, electron-electron, and electron-phonon scattering were analyzed, contribution of these mechanisms to resistivity were discussed, taking into consideration existing theoretical models and available experimental data, where some new results and ideas were investigated.

Elastic and inelastic scattering of fast neutrons from iron, nickel and tungsten

1969 ◽  
Vol 125 (3) ◽  
pp. 641-653 ◽  
Author(s):  
Kineo Tsukada ◽  
Shigeya Tanaka ◽  
Yoshiaki Tomita ◽  
Michio Maruyama
Keyword(s):  
Inelastic Scattering ◽  
Fast Neutrons ◽  
Elastic And Inelastic Scattering ◽  
Iron Nickel ◽  
And Tungsten

Concentration Dependence of the Surface Tension of Three and Four-Component Systems with Peculiarities in the Surface Tension Isotherms of Lateral Binary Melts

2021 ◽  
Vol 1022 ◽  
pp. 194-202
Author(s):  
R.Kh. Dadashev ◽  
R.A. Kutuev
Keyword(s):  
Experimental Data ◽  
Surface Tension ◽  
Concentration Dependence ◽  
Experimental Error ◽  
Binary Systems ◽  
Experimental Studies ◽  
Study Results ◽  
Component Systems ◽  
Minimum Depth ◽  
Surface Tension Isotherms

The experimental study results of the melts concentration dependence of the surface tension of the four-component indium-tin-lead-bismuth system and its constituent binary systems of indium-tin, indium-lead, indium-bismuth, tin-lead, tin-bismuth, lead-bismuth are presented in the paper. It is shown that the concentration dependence of the melts surface tension of the In-Sn-Pb-Bi four-component system can be predicted from the data on ST (surface tension) values of lateral binary systems. Features in the ST isotherms in the form of a minimum are observed only in the indium-tin lateral system from all lateral binaries. A distinctive feature of the detected minimum is that the minimum depth slightly exceeds the experimental error. Therefore, in addition to the fact that the area of average compositions was studied more thoroughly, we carried out the surface tension measurements by two independent methods. The experimental data obtained by both methods coincide within the experimental error and indicate the extremum availability on ST isotherms. Thus, ST experimental studies by two independent methods confirmed the presence of a flat minimum on ST isotherms of the indium-tin binary system increasing the reliability of the obtained data. The obtained outcomes and their comparison with experimental data have shown that the considered models for predicting surface properties based on data due to similar properties of lateral binary systems adequately reflect the experimental dependences. However, the prediction model based on Kohler's method of excess values describes the experimental curves more accurately.

Concentration dependence of interdiffusion coefficients in Cu-Fe-Ni system

2013 ◽  
Vol 114 (1) ◽  
pp. 54-62 ◽  
Author(s):  
Ü. Ugaste ◽  
A. A. Kodentsov ◽  
F. J. J. van Loo
Keyword(s):  
Concentration Dependence ◽  
Interdiffusion Coefficients

The Meyer–Neldel Rule in Conduction Mechanism of the Electrospun ZnO Nanofibers

NANO ◽  
2016 ◽  
Vol 11 (03) ◽  
pp. 1650025 ◽  
Author(s):  
Andrzej Stafiniak ◽  
Marek Tłaczała
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Conduction Mechanism ◽  
Deep Level ◽  
Electrical Measurements ◽  
Thermally Activated ◽  
Theoretical Assumptions ◽  
Different Temperatures ◽  
Zno Nanofibers ◽  
Improved Model

An analytical model describing the conductivity of ZnO nanofibers depending on the grains size is proposed. The research is based on the thermal dc electrical measurements of a single electrospun ZnO nanofiber calcined at different temperatures. In the our previous research, we showed that electrical conduction of ZnO nanofibers is mainly thermally activated. The activation energy of conductivity was strongly dependent on the grain size, which in turn depended on the calcination temperature. This could be due to migration of a point defect in the grain of ZnO and could change the carrier concentration. Our recent studies have shown that ZnO nanofibers behavior is consistent with the Meyer–Neldel rule. This indicates an exponential energy distribution of deep level traps in the material. Based on the theoretical assumptions and experimental data, the improved model of conductivity in a single ZnO nanofiber calcined at different temperatures was proposed.

Representation of binary excess enthalpy data

1982 ◽  
Vol 47 (12) ◽  
pp. 3171-3176 ◽  
Author(s):  
Miloslav Prchal ◽  
Vladimír Dohnal ◽  
František Veselý
Keyword(s):  
Experimental Data ◽  
Concentration Dependence ◽  
Excess Enthalpy ◽  
Electrolyte Solutions ◽  
Extensive Test ◽  
Enthalpy Data

An extensive test of five correlation relations for the concentration dependence of excess enthalpy of non-electrolyte solutions was carried out. The Redlich-Kister, root and reciprocal expansions, the SSF and Wilson equations were used to represent experimental data of 54 systems of different character. For the representation of data of symmetric and slightly asymmetric systems, we recommend the Redlich-Kister polynomial, more asymmetric systems are described excellently by the SSF equation.

scholarly journals The dispersion in spherical statistical optical potential (SOM) from the interaction of fast neutrons with197Au nucle

2019 ◽  
Vol 17 (40) ◽  
pp. 88-94
Author(s):  
Fatimah Fadhil Abd Ali
Keyword(s):  
Experimental Data ◽  
Surface Energy ◽  
Fermi Surface ◽  
Energy Range ◽  
Optical Potential ◽  
Fast Neutrons ◽  
Heavy Nuclei ◽  
Real Potential ◽  
Imaginary Potential ◽  
Experimental Bench

A statistical optical potential has been used to analyze andevaluate the neutron interaction with heavy nuclei 197Au at theneutron energy range (1-20 MeV). Empirical formulae of the opticalpotentials parameters are predicted by using ABAREX Code withminimize accuracy compared with experimental bench work data.The total elastic, absorption, shape elastic and total compound crosssections are calculated for different target nuclei and differentincident neutron energies to predict the appropriate opticalparameters that suit the present interaction. Also the dispersionrelation linking between real and imaginary potential is analyzedwith more accuracy. The results indicate the behavior of thedispersion contribution in imaginary potential has a parabolic changeabout the Fermi surface energy while in the real potential it fall withincreasing the neutron energy. Good agreements have been achievedwith the available experimental data

The Growth Rates of Intermediate Phases in Co/Si Diffusion Couples: Bulk Versus Thin-Film Studies

1989 ◽  
Vol 148 ◽  
Author(s):  
C. H. Jan ◽  
J. C. Lin ◽  
Y. A. Chang
Keyword(s):  
Experimental Data ◽  
Growth Rates ◽  
Film Studies ◽  
Bulk Diffusion ◽  
Diffusion Equations ◽  
Diffusion Couples ◽  
Intermediate Phases ◽  
Diffusion Controlled ◽  
Composition Profiles ◽  
Interdiffusion Coefficients

ABSTRACTBulk diffusion couples of Co/Si were annealed at 800, 900, 1000, 1050 and 1100°C for periods ranging from 24 hours to one month. Growth rates of the intermediate phases, Co2Si, CoSi and CoSi2, as well as the composition profiles across the couples were determined by optical microscopy and electron probe microanalysis (EPMA). Using the solution to the multiphase binary diffusion equations and the experimental data, the interdiffusion coefficients for Co2Si, CoSi and CoSi2 are obtained as a function of temperature. The activation energies obtained are 140, 160 and 190 KJ/mole for Co2Si, CoSi and CoSi2, respectively. The generally small interdiffusion coefficient of CoSi2 and its high activation energy cause the growth rate of CoSi2 to be extremely small at low temperatures.The interdiffusion coefficients for Co2Si, CoSi and CoSi2 at 545°C are obtained by extrapolation of the high-temperatures data. Using these data and solving numerically the diffusion equations with the appropriate boundary conditions, the growth of Co2Si, CoSi and CoSi2 is calculated as a function of time. The calculated results are in good agreement with the experimental data reported in the literature. This study demonstrates clearly that the initial absence of the CoSi2 phase is due to diffusion-controlled rather than nucleation-controlled kinetics. This phenomenon may be quite common in many thin-fiflm metal/Si couples.

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