Atomic transport in Xe-irradiated Ni/SiO2 bilayers

1988 ◽  
Vol 3 (6) ◽  
pp. 1072-1081 ◽  
Author(s):  
T. Banwell ◽  
M-A. Nicolet
Keyword(s):  
Phenomenological Model ◽  
Transport Mechanism ◽  
Irradiation Dose ◽  
Irradiation Temperature ◽  
Analytical Tool ◽  
Recoil Implantation ◽  
Atomic Transport

Parametric experiments are described that characterize the process of atomic relocation in Ni/SiO2 bilayers induced by Xe irradiation. The parameters varied are the irradiation temperature (− 196 to + 500 °C) and the Xe irradiation dose (0.01−15 × 1015cm−2). Backscattering spectrometry of the irradiated samples after removal of the unreacted Ni film is the main analytical tool. A phenomenological model is given that describes the results quantitatively. It is deduced that secondary recoil implantation followed by subsequent redistribution within the cascade's lifetime produces the dominant transport mechanism responsible for incorporating Ni into the SiO2.

Study of atomic transport mechanism of oxygen during thermal nitridation of silicon dioxide

1991 ◽  
Vol 51 (3-4) ◽  
pp. 133-138 ◽  
Author(s):  
A. Serrari ◽  
J.L. Chartier ◽  
R. Le Bihan ◽  
S. Rigo ◽  
J.C. Dupuy
Keyword(s):  
Silicon Dioxide ◽  
Transport Mechanism ◽  
Atomic Transport ◽  
Thermal Nitridation

Temperature dependence of the amorphization of NiTi irradiated with Ni ions

1990 ◽  
Vol 5 (5) ◽  
pp. 932-941 ◽  
Author(s):  
P.J. Maziasz ◽  
D.F. Pedraza ◽  
J.P. Simmons ◽  
N.H. Packan
Keyword(s):  
Temperature Dependence ◽  
Irradiation Dose ◽  
Small Volume ◽  
Volume Fraction ◽  
Amorphous Material ◽  
Irradiation Temperature ◽  
Thermally Activated ◽  
Martensitic Microstructure ◽  
Small Volume Fraction ◽  
Annealing Experiments

NiTi was irradiated with Ni ions at various temperatures in order to study the temperature dependence of the irradiation-induced crystalline-to-amorphous transition. The irradiations were conducted above the Af temperature, and thus the specimens contained only the ordered B2 (CsC1) phase. The irradiations to similar doses at 150, 200, and 250°C showed that the amorphization kinetics slow down appreciably as the temperature is increased in this range. No amorphization was detected at irradiation temperatures of 350°C or higher, even after doses of 4 dpa. The small volume fraction of amorphous material observed after irradiation to 0.67 dpa at 250°C indicates that the cutoff temperature for amorphization is in the vicinity of this temperature. The amorphous regions of partly amorphous samples are distributed in a nonuniform manner and exhibit a morphology similar to the martensitic microstructure that existed in the specimens before heating to the irradiation temperature. Large amorphous regions in these samples exhibit some very fine crystalline debris which tends to disappear with increasing irradiation dose. Post-irradiation annealing experiments indicated that no thermally activated crystallization occurred during irradiation at temperatures up to 250°C.

scholarly journals Electric Transport in Gold-Covered Sodium–Alginate Free-Standing Foils

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 565
Author(s):  
Carlo Barone ◽  
Monica Bertoldo ◽  
Raffaella Capelli ◽  
Franco Dinelli ◽  
Piera Maccagnani ◽  
...  
Keyword(s):  
Sodium Alginate ◽  
Phenomenological Model ◽  
Transport Mechanism ◽  
Gold Clusters ◽  
Electric Transport ◽  
Free Standing ◽  
Metallic Behavior ◽  
Transparent Conducting ◽  
Gold Thickness ◽  
Anomalous Expansion

The electric transport properties of flexible and transparent conducting bilayers, realized by sputtering ultrathin gold nanometric layers on sodium–alginate free-standing films, were studied. The reported results cover a range of temperatures from 3 to 300 K. In the case of gold layer thicknesses larger than 5 nm, a typical metallic behavior was observed. Conversely, for a gold thickness of 4.5 nm, an unusual resistance temperature dependence was found. The dominant transport mechanism below 70 K was identified as a fluctuation-induced tunneling process. This indicates that the conductive region is not continuous but is formed by gold clusters embedded in the polymeric matrix. Above 70 K, instead, the data can be interpreted using a phenomenological model, which assumes an anomalous expansion of the conductive region upon decreasing the temperature, in the range from 300 to 200 K. The approach herein adopted, complemented with other characterizations, can provide useful information for the development of innovative and green optoelectronics.

Highly collective atomic transport mechanism in high-entropy glass-forming metallic liquids

2019 ◽  
Vol 35 (1) ◽  
pp. 44-47 ◽  
Author(s):  
Changjiu Chen ◽  
Kaikin Wong ◽  
Rithin P. Krishnan ◽  
Lei Zhifeng ◽  
Dehong Yu ◽  
...  
Keyword(s):  
Transport Mechanism ◽  
High Entropy ◽  
Glass Forming ◽  
Atomic Transport ◽  
Metallic Liquids

LPCD framework: Analytical tool or psychological model?

2018 ◽  
Vol 41 ◽  
Author(s):  
David Danks
Keyword(s):  
Decision Making ◽  
Analytical Tool ◽  
Mathematical Framework ◽  
Bayesian Decision ◽  
Perceptual Decision Making ◽  
Psychological Model ◽  
Psychological Reality ◽  
Psychological Theories ◽  
Target Article ◽  
Bayesian Decision Making

AbstractThe target article uses a mathematical framework derived from Bayesian decision making to demonstrate suboptimal decision making but then attributes psychological reality to the framework components. Rahnev & Denison's (R&D) positive proposal thus risks ignoring plausible psychological theories that could implement complex perceptual decision making. We must be careful not to slide from success with an analytical tool to the reality of the tool components.

Voids in Irradiated Tungsten and Molybdenum

1969 ◽  
Vol 27 ◽  
pp. 190-191
Author(s):  
Robert C. Rau ◽  
Robert L. Ladd
Keyword(s):  
Melting Point ◽  
Fast Neutron ◽  
Neutron Irradiation ◽  
Elevated Temperatures ◽  
Irradiation Temperature ◽  
The Body ◽  
Face Centered Cubic ◽  
Body Centered Cubic ◽  
Cubic Metals ◽  
Face Centered

Recent studies have shown the presence of voids in several face-centered cubic metals after neutron irradiation at elevated temperatures. These voids were found when the irradiation temperature was above 0.3 Tm where Tm is the absolute melting point, and were ascribed to the agglomeration of lattice vacancies resulting from fast neutron generated displacement cascades. The present paper reports the existence of similar voids in the body-centered cubic metals tungsten and molybdenum.

Effects of Vincristine on Endothelial Microtubules in the Spinal Cord

1976 ◽  
Vol 34 ◽  
pp. 58-59
Author(s):  
John L. Beggs ◽  
John D. Waggener ◽  
Wanda Miller
Keyword(s):  
Spinal Cord ◽  
Biological Activity ◽  
Horseradish Peroxidase ◽  
Transport Mechanism ◽  
Vasogenic Edema ◽  
Vesicular Transport ◽  
Close Proximity

Microtubules (MT) are versatile organelles participating in a wide variety of biological activity. MT involvement in the movement and transport of cytoplasmic components has been well documented. In the course of our study on trauma-induced vasogenic edema in the spinal cord we have concluded that endothelial vesicles contribute to the edema process. Using horseradish peroxidase as a vascular tracer, labeled endothelial vesicles were present in all situations expected if a vesicular transport mechanism was in operation. Frequently,labeled vesicles coalesced to form channels that appeared to traverse the endothelium. The presence of MT in close proximity to labeled vesicles sugg ested that MT may play a role in vesicular activity.

A microscopic marker experiment study on high temperature oxidation of Ni-Al alloy

1986 ◽  
Vol 44 ◽  
pp. 514-515
Author(s):  
Shou-kong Fan
Keyword(s):  
Transport Mechanism ◽  
High Temperature Oxidation ◽  
Transverse Section ◽  
Al Alloy ◽  
Metal Interface ◽  
Electron Microscopic ◽  
Temperature Oxidation ◽  
Analytical Electron ◽  
Microscopic Studies ◽  
First Time

Transmission and analytical electron microscopic studies of scale microstructures and microscopic marker experiments have been carried out in order to determine the transport mechanism in the oxidation of Ni-Al alloy. According to the classical theory, the oxidation of nickel takes place by transport of Ni cations across the scale forming new oxide at the scale/gas interface. Any markers deposited on the Ni surface are expected to remain at the scale/metal interface after oxidation. This investigation using TEM transverse section techniques and deposited microscopic markers shows a different result,which indicates that a considerable amount of oxygen was transported inward. This is the first time that such fine-scale markers have been coupled with high resolution characterization instruments such as TEM/STEM to provide detailed information about evolution of oxide scale microstructure.

Sign in / Sign up

Export Citation Format

Share Document