The Influence of Dose Rate on the Formation of CrSi2 by Ion Mixing

1987 ◽  
Vol 93 ◽  
Author(s):  
S.-J. Kim ◽  
D. N. Jamieson ◽  
M-A. Nicolet ◽  
R. S. Averback
Keyword(s):  
Growth Rate ◽  
Dose Rate ◽  
Ion Irradiation ◽  
Diffusion Theory ◽  
Layer Compound ◽  
Enhanced Diffusion ◽  
Silicide Layer ◽  
Radiation Enhanced Diffusion ◽  
Lower Dose Rate ◽  
The Relationship

ABSTRACTThe relationship between growth rate of CrSi2 and dose rate during Xe ion irradiation at 500K is investigated. Dose raies difffering by up to a factor of 40 have been utilized to study the relationship. For a fixed total dose, a lower dose rate results in a thicker silicide layer compound to a higher dose rate. The results are explained from radiation-enhanced diffusion theory.

The oestrogenicity of equol in sheep

1984 ◽  
Vol 103 (3) ◽  
pp. 395-399 ◽  
Author(s):  
R. Kaziro ◽  
J. P. Kennedy ◽  
E. R. Cole ◽  
P. T. Southwell-Keely
Keyword(s):  
Growth Rate ◽  
Plasma Concentration ◽  
Plasma Level ◽  
Dose Rate ◽  
Dehydrogenase Activity ◽  
Intramuscular Injection ◽  
Uterine Weight ◽  
Lower Dose Rate ◽  
Short Time ◽  
Glucose 6 Phosphate Dehydrogenase

ABSTRACT The effects of intramuscular injection of synthetic racemic equol (±3-(4-hydroxyphenyl)-3,4-dihydro2H-1-benzopyran-7-ol) into wethers have been examined with respect to maintenance of plasma level, teat growth rate and the activity of the respiratory enzyme glucose-6-phosphate dehydrogenase. At a dose rate of 1·03 mmol/day a steady rise in 'total' (free plus conjugated) equol in plasma occurred to 1·78μmol/l in 4 days. A dose rate of 2·07 mmol/day produced only a further slight increase in plasma equol. At a lower dose rate of 0·52 mmol/day the plasma concentration reached 0·62 μmol/l in 2 days and this was not exceeded thereafter. At the dose rate of 1·03 mmol/day over 7 days significant increases in teat length and glucose-6-phosphate dehydrogenase activity occurred but no significant changes were observed at the dose rate of 0·52 mmol/day. It appears that threshold levels of intake of equol which maintain a plasma level of about 1·65 μmol/l are needed for oestrogenic effects to become apparent within a relatively short time. Administration of 1·03 mmol/day over 5 days to ovariectomized ewes produced significant increases in uterine weight equivalent to those produced by 92 nmol stilboestrol dipropionate. Thus stilboestrol was apparently 56000 times more potent than racemic equol. J. Endocr. (1984) 103, 395–399

scholarly journals Correction to: Theoretical prediction of radiation-enhanced diffusion behavior in nickel under self-ion irradiation

2020 ◽  
Vol 31 (9) ◽  
Author(s):  
Xiao-Ya Chen ◽  
A-Li Wen ◽  
Cui-Lan Ren ◽  
Cheng-Bin Wang ◽  
Wei Zhang ◽  
...  
Keyword(s):  
Theoretical Prediction ◽  
Ion Irradiation ◽  
Diffusion Behavior ◽  
Enhanced Diffusion ◽  
Radiation Enhanced Diffusion

Sink Strength Evolution of Heavy Ion Irradiated Nickel

1998 ◽  
Vol 540 ◽  
Author(s):  
P. Fielitz ◽  
M.-P. Macht ◽  
V. Naundorf ◽  
H. Wollenberger
Keyword(s):  
Ion Irradiation ◽  
Heavy Ion ◽  
Irradiation Temperature ◽  
Sink Strength ◽  
Enhanced Diffusion ◽  
Self Diffusion ◽  
Spatially Resolved ◽  
Radiation Enhanced Diffusion ◽  
Strength Evolution ◽  
Different Depths

AbstractAtom transport under irradiation is determined by the concentration of freely migrating defects, which depends on the dynamical equilibrium between production and annihilation rates. In order to determine effective values of both of these quantities for the case of ion irradiation, spatially resolved self-diffusion measurements were performed on single crystals of nickel which contained several thin tracer layers at different depths.For fixed depth the radiation-enhanced diffusion coefficient (DK) was determined as function of displacement rate (K0) and fluence (Φ). The DK essentially representing the ratio of the rates of production and annihilation was found to be proportional to K0 for 800 K irradiation temperature and to K00.4for Ni and K00.4for Kr irradiation at 950 K. It is independent of Φ for 800 K and decreases with increasing Φ for 950 K.

scholarly journals Analysis of Experiments in Helium Microbeam Mixing

1991 ◽  
Vol 235 ◽  
Author(s):  
John B. Davis ◽  
R. E. Benenson ◽  
David Peak
Keyword(s):  
Dose Rate ◽  
Ion Beam ◽  
Liquid Nitrogen Temperature ◽  
Enhanced Diffusion ◽  
Interface Width ◽  
Interface Growth ◽  
Radiation Enhanced Diffusion ◽  
Order Of Magnitude ◽  
Constant Dose ◽  
Diffusion Of Vacancies

ABSTRACTWe have continued to investigate ion-beam mixing in bilay-er targets irradiated by 2-MeV He+ microbeams at room temperature. Although we have previously reported a linear dependence of interface width on dose for Cu/Al targets 1, more extensive results have not supported this conclusion, within statistical uncertainty, it appears that the interface width in Cu/Al (1) is proportional to the square root of dose, at constant dose rate, (2) is larger in Al than in Cu, for the same dose, (3) is proportional to the 1/4 power of dose rate, and (4) is absent at liquid nitrogen temperature. Calculations of the expected interface growth rate from a radiation-enhanced diffusion model have provided order-of-magnitude agreement with observed rates. Additionally, intermixing of Cu and Al outside the damaged area may indicate significant transverse diffusion of vacancies.

The Effect of Atomic Mixing on the Depth Profiles of Metal Markers in Silicon

1983 ◽  
Vol 27 ◽  
Author(s):  
B. V. King ◽  
D. G. Tonn ◽  
I.S.T. Tsong ◽  
J. A. Leavitt
Keyword(s):  
Thin Film ◽  
Diffusion Theory ◽  
Diffusion Constant ◽  
Enhanced Diffusion ◽  
Depth Profiles ◽  
Mixing Effects ◽  
Radiation Enhanced Diffusion ◽  
Experimental Values ◽  
Atomic Mixing

ABSTRACTAtomic mixing effects of sputter depth-profiles are modeled by a diffusion theory with a depth-dependent diffusion constant D. The model is compared to SIMS depth profiles, using 5 keV Ar+ bombardment of dilute thin-film multilayers of Al, Ag, Ti and Mo in silicon. The experimental values of D can be explained by cascade mixing and radiation enhanced diffusion within the cascade for Al, Ag and Ti markers but not for the Mo marker.

scholarly journals The Effect of Ion Irradiation on Inert Gas Bubble Mobility

1991 ◽  
Vol 235 ◽  
Author(s):  
Dale E. Alexander ◽  
R. C. Birtcher
Keyword(s):  
Electron Microscopy ◽  
Volume Diffusion ◽  
Ion Irradiation ◽  
Diffusion Mechanism ◽  
Inert Gas ◽  
Gas Bubble ◽  
Enhanced Diffusion ◽  
Transmission Electron ◽  
Radiation Enhanced Diffusion ◽  
Bubble Transport

ABSTRACTThe effect of Al ion irradiation on the mobility of Xe gas bubbles in Al thin films was investigated. Transmission electron microscopy was used to determine bubble diffusivities in films irradiated and/or annealed at 673K, 723K and 773K. Irradiation increased bubble diffusivity by a factor of 2–9 over that due to thermal annealing alone. The Arrehnius behavior and dose rate dependence of bubble diffusivity are consistent with a radiation enhanced diffusion phenomenon affecting a volume diffusion mechanism of bubble transport.

Computer Simulation of Marker Evolution Upon Ion Irradiation

1985 ◽  
Vol 54 ◽  
Author(s):  
Fu-Zhai Cui ◽  
Heng-De Li ◽  
Bai-Xin Liu
Keyword(s):  
Ion Irradiation ◽  
Ion Beam ◽  
Monte Carlo Code ◽  
Ion Beam Mixing ◽  
Enhanced Diffusion ◽  
Radiation Enhanced Diffusion ◽  
Marker Profile ◽  
Dynamic Target ◽  
The Subject ◽  
Marker Evolution

ABSTRACTIn ion beam mixing, the subject on the marker evolution of Si/Pt/Si target during 300 keV Xe ion irradiation has been an interesting topic of recent years. A cottputer simulation for this system by using the Monte Carlo code TCIS-4 is reported here. Dynamic target model was employed. Some radiation-enhanced diffusion and relaxation of the displacement cascades were also considered. Results of this simulation study reveal the evolution of Pt marker profile with fluences during bombardment. The shifts of Pt marker and the dispersions evaluated from the profiles agree fairly well with experimental date, demonstrating a reslistic model of the target being irradiated is important.

Theoretical prediction of radiation-enhanced diffusion behavior in nickel under self-ion irradiation

2020 ◽  
Vol 31 (8) ◽  
Author(s):  
Xiao-Ya Chen ◽  
A-Li Wen ◽  
Cui-Lan Ren ◽  
Cheng-Bin Wang ◽  
Wei Zhang ◽  
...  
Keyword(s):  
Theoretical Prediction ◽  
Ion Irradiation ◽  
Diffusion Behavior ◽  
Enhanced Diffusion ◽  
Radiation Enhanced Diffusion

Radiation Induced Impurity Precipitation in Mgo

1985 ◽  
Vol 60 ◽  
Author(s):  
S. Clement ◽  
E. R. Hodgson
Keyword(s):  
Absorption Band ◽  
Optical Absorption ◽  
Dose Rate ◽  
Reduction Process ◽  
High Dose ◽  
Optical Absorption Band ◽  
Enhanced Diffusion ◽  
Dose Rates ◽  
Radiation Enhanced Diffusion ◽  
Radiation Induced

AbstractIn MgO irradiated at high dose rates and high temperatures with 1.8 MeV electrons, a suppression of the Fe3+ optical absorption band at 290 nm is observed. This suppression, a function of both dose rate and temperature, is consistent with a reduction process induced by oxygen displacement damage. Both thermal and radiation enhanced diffusion are involved and lead to the formation of iron containing precipitates. Similar results have been obtained for Ni2+.

Temperature Dependence of Ion Mixing Of Markers in Zr

1986 ◽  
Vol 74 ◽  
Author(s):  
S. -J. Kim ◽  
M. -A. Nicolet ◽  
R. S. Averback
Keyword(s):  
Thin Films ◽  
Temperature Dependence ◽  
Diffusion Theory ◽  
Irradiation Temperature ◽  
Enhanced Diffusion ◽  
Radiation Enhanced Diffusion

AbstractIon mixing of thin markers in Zr was investigated by irradiating with 660 keV Kr++ ions at temperatures between 300 to 423 K. Very thin films of vacuum evaporated Ti, Cr, Fe, Co, Ni, Cu+ Hf, W, and Au served as markers. The samples were analyzed by 2 MeV He backscattering spectrometry. The marker elements that are likely to dissolve interstitially in Zr have higher mixing efficiencies at elevated irradiation temperature than the markers that are likely to dissolve substitutionally. The results are explained by radiation-enhanced diffusion theory.

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