ON THE TEMPERATURE DEPENDENCE OF PINNING BY IRRADIATION-INDUCED POINT DEFECTS IN COPPER

1971 ◽  
Vol 32 (C2) ◽  
pp. C2-151-C2-152
Author(s):  
P. WINTERHAGER ◽  
G. ROTH ◽  
R. JOHN ◽  
K. LÜCKE
Keyword(s):  
Temperature Dependence ◽  
Point Defects

Interaction of Point Defects in Ice

1978 ◽  
Vol 21 (85) ◽  
pp. 115-122
Author(s):  
J. H. Bilgram ◽  
H. Gränicher
Keyword(s):  
Experimental Data ◽  
Dielectric Properties ◽  
Temperature Dependence ◽  
Point Defects ◽  
Low Frequency ◽  
Defect Concentration ◽  
Dielectric Measurements ◽  
Long Time ◽  
Nmr Techniques ◽  
Bjerrum Defect

AbstractThe interaction of point detects in ice has been neglected for a long time. Experimental data obtained from dielectric measurements on HF-doped crystals stimulated a new evaluation of the possibility of an interaction between Bjerrum defects and ions. In a previous paper it has been shown that this leads us to assume the existence of aggregates of Bjerrum defects and ions. In this paper these aggregates and Bjerrum defects are used to explain the dielectric properties of ice, especially the temperature dependence of the product of the high and low frequency conductivity σ0σ∞.The interaction of Bjerrum defects and impurity molecules leads to a dependence of the concentration of frenkel pairs on Bjerrum-defect concentration. At HF concentrations above the native Bjerrum-defect concentration the formation of a Frenkel pair is enhanced. This leads to the fast out-diffusion which has been studied in highly doped crystals by means of NMR techniques.

The Effect of Point Defects Induced by Fast Neutron Irradiation on the Thermal Conductivity of Boron Carbide

2017 ◽  
Vol 726 ◽  
pp. 153-158
Author(s):  
Ai Bing Du ◽  
Zhi Xue Qu ◽  
Xi Ping Su ◽  
Xiao Xiao
Keyword(s):  
Thermal Conductivity ◽  
Boron Carbide ◽  
Temperature Dependence ◽  
Fast Neutron ◽  
Point Defects ◽  
Thermal Conduction ◽  
Conduction Model ◽  
Initial Stage ◽  
Fast Neutron Irradiation ◽  
Conduction Behavior

The thermal conduction behavior of the neutron absorbing ceramic boron carbide in the initial stage of the irradiation was analyzed and a classical thermal conduction model was used to estimate the variation of the thermal conductivity in this paper. The calculated thermal conductivity using the model shows a large degration in the initial stage of irradiation. As the burnup increases, the thermal conductivity turns to be free of temperature dependence. These calculated results are consistent well with the expermental data of thermal conductivity of the irradiated boron carbide, which may suggest that the variation of the thermal conductivity of boron carbide is predominantly determined by the point defects scattering in the initial stage of irradiation.

Effect of annealing on the resistivity of self damaged plutonium

1965 ◽  
Vol 284 (1398) ◽  
pp. 344-353 ◽  
Keyword(s):  
Temperature Dependence ◽  
Point Defects ◽  
Low Temperatures ◽  
Isochronal Annealing ◽  
Anomalous Temperature Dependence ◽  
Anomalous Temperature ◽  
Annealing Stage ◽  
Accumulation Of Defects ◽  
Annealing Experiments

When samples of α plutonium are stored at low temperatures their resistivities increase owing to the accumulation of defects produced by the radioactive disintegration of the nuclei. Isochronal annealing experiments have been performed on α plutonium which show that this additional resistivity recovers in two distinct stages centred at ca . 75 and 150 °K respectively. In δ stabilized plutonium the first annealing stage is more pronounced and occurs at lower temperatures, the values of which are dependent on the concentration of aluminium used to stabilize the δ phase. Isochronal annealing experiments have also been performed on heavily damaged samples of α plutonium and yield further information on the anomalous temperature dependence of the resistivity changes brought about by self irradiation at low temperatures. The correlation between the observed resistivity changes and corresponding changes in the concentration of point defects is discussed.

scholarly journals Electronic-Excitation-Induced Processing in GaSb Compound Nanoparticles

2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
H. Yasuda ◽  
H. Mori
Keyword(s):  
Temperature Dependence ◽  
Point Defects ◽  
Structural Changes ◽  
Electronic Excitation ◽  
The Other ◽  
Two Phase ◽  
Electron Dose ◽  
Total Electron ◽  
Transmission Electron

Temperature dependence of electronic-excitation-induced structural changes in nanoparticles has been studied by in situ transmission electron microscopy. When GaSb nanoparticles kept at 340 K were excited by 25 keV electrons, the compound transforms to the porous compound or the two-phase structure consisting of an antimony core and a gallium shell with increasing the total electron dose. On the other hand, in GaSb nanoparticles kept at 293 K the structure remains the original compound phase. It is suggested that such temperature dependence of the structural changes may arise from synergetic behaviors of point defects introduced athermally by the excitation and thermal mobility.

Interaction of Point Defects in Ice

1978 ◽  
Vol 21 (85) ◽  
pp. 115-122 ◽  
Author(s):  
J. H. Bilgram ◽  
H. Gränicher
Keyword(s):  
Experimental Data ◽  
Dielectric Properties ◽  
Temperature Dependence ◽  
Point Defects ◽  
Low Frequency ◽  
Defect Concentration ◽  
Dielectric Measurements ◽  
Long Time ◽  
Nmr Techniques ◽  
Bjerrum Defect

Abstract The interaction of point detects in ice has been neglected for a long time. Experimental data obtained from dielectric measurements on HF-doped crystals stimulated a new evaluation of the possibility of an interaction between Bjerrum defects and ions. In a previous paper it has been shown that this leads us to assume the existence of aggregates of Bjerrum defects and ions. In this paper these aggregates and Bjerrum defects are used to explain the dielectric properties of ice, especially the temperature dependence of the product of the high and low frequency conductivity σ 0 σ ∞. The interaction of Bjerrum defects and impurity molecules leads to a dependence of the concentration of frenkel pairs on Bjerrum-defect concentration. At HF concentrations above the native Bjerrum-defect concentration the formation of a Frenkel pair is enhanced. This leads to the fast out-diffusion which has been studied in highly doped crystals by means of NMR techniques.

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