Elevated temperature dependence of hardness in tri-metallic nano-scale metallic multilayer systems

ABSTRACTThe temperature dependence of etch rate, surface morphology and atomic composition, and depth of hydrogen passivation of Si dopants in n-type GaAs and AIGaAs has been measured for reactive ion etching in C2H6 /H2. The etching of GaAs shows an increase of a factor of two between 150 and 250°C, decreasing at higher temperatures, while there is no temperature dependence for the etch rate of AlGaAs over the range 50-350°C. The As-to-Ga ratio in the nearsurface region of GaAs remains unchanged over the whole temperature range investigated and there is no polymer deposition. The etched surface morphology is smooth for both GaAs and AIGaAs for all temperatures while the depth of Si dopant passivation by hydrogen shows an increase with increasing substrate temperature during the etching treatment.

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Measuring the Elevated Temperature Dependence of Up-Conversion in Nd:YAG

IEEE Journal of Selected Topics in Quantum Electronics ◽

10.1109/jstqe.2014.2336776 ◽

2015 ◽

Vol 21 (1) ◽

pp. 329-336 ◽

Cited By ~ 3

Author(s):

RenPeng Yan ◽

Sung Jin Yoon ◽

Stephen J. Beecher ◽

Jacob I. Mackenzie

Keyword(s):

Elevated Temperature ◽

Temperature Dependence

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Thermo-mechanical characterization of shale using nanoindentation

Scientific Reports ◽

10.1038/s41598-021-98251-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yanbo Wang ◽

Debora Lyn Porter ◽

Steven E. Naleway ◽

Pania Newell

Keyword(s):

Fracture Toughness ◽

Elastic Modulus ◽

Elevated Temperature ◽

Mechanical Response ◽

Mechanical Performance ◽

Substantial Impact ◽

Fracture Properties ◽

Nano Scale ◽

Bedding Planes ◽

Mechanical And Fracture Properties

AbstractShale can be a potential buffer for high-level radioactive nuclear wastes. To be an effective buffer while subject to waste heat, shale's mechanical response at elevated temperature must be known. Many researchers have experimentally characterized the mechanical behavior of various shales at different length scales in adiabatic conditions. However, its mechanical performance at elevated temperatures at the nano-scale remains unknown. To investigate the temperature dependency of nanomechanical properties of shale, we conducted both experimental and numerical studies. In this study, we measured mechanical and fracture properties of shale, such as hardness, elastic modulus, anisotropy, and fracture toughness from 25 °C up to 300 °C at different bedding planes. Statistical analysis of the results suggests that hardness and fracture toughness significantly increased at temperatures from 100 to 300 °C; while, temperature does not have a significant impact on elastic modulus. Data also shows that the bedding plane orientations have a substantial impact on both mechanical and fracture properties of shale at the nano-scale leading to distinct anisotropic behavior at elevated temperature below 100 °C. Additionally, we numerically investigated the mechanical performance of the shale samples at room temperature to gain an insight into its mechanical response through the thickness. Numerical results were validated against the experimental results, confirming the simulation can be used to predict shale deformation at the nano-scale or potentially be used in multi-scale simulations.

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Elevated temperature dependence of the anisotropic visible-to-ultraviolet dielectric function of monoclinic β-Ga2O3

Applied Physics Letters ◽

10.1063/1.5010936 ◽

2018 ◽

Vol 112 (4) ◽

pp. 041905 ◽

Cited By ~ 6

Author(s):

A. Mock ◽

J. VanDerslice ◽

R. Korlacki ◽

J. A. Woollam ◽

M. Schubert

Keyword(s):

Elevated Temperature ◽

Temperature Dependence ◽

Dielectric Function

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Less reactive dipoles of diazodicarbonyl compounds in reaction with cycloaliphatic thioketones – First evidence for the 1,3-oxathiole–thiocarbonyl ylide interconversion

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.9.309 ◽

2013 ◽

Vol 9 ◽

pp. 2751-2761 ◽

Cited By ~ 10

Author(s):

Valerij A Nikolaev ◽

Alexey V Ivanov ◽

Ludmila L Rodina ◽

Grzegorz Mlostoń

Keyword(s):

Elevated Temperature ◽

Temperature Dependence ◽

Room Temperature ◽

Product Type ◽

Main Reaction ◽

Main Reaction Product ◽

Cascade Process ◽

Energy Profile

Acyclic diazodicarbonyl compounds react at room temperature with cycloaliphatic thioketones, e.g. 2,2,4,4-tetramethyl-3-thioxocyclobutanе-1-one and adamantanethione, via a cascade process in which the key step is a 1,5-electrocyclization of the intermediate thiocarbonyl ylide leading to tetrasubstituted spirocyclic 1,3-oxathioles. The most reactive diazodicarbonyl compound was diazoacetylacetone. In the case of dimethyl diazomalonate competitive 1,3-electrocyclization yielded the corresponding thiirane at elevated temperature, which after spontaneous desulfurization produced a tetrasubstituted alkene. To explain the observed temperature dependence of the main reaction product type obtained from dimethyl diazomalonate and 2,2,4,4-tetramethyl-3-thioxocyclobutanе-1-one as well as to verify reversibility of the thiocarbonyl ylide and 1,3-oxathiole interconversion, the calculations of the energy profile for the transformation of 1,3-oxathiole to alkene were performed at the DFT PBE1PBE/6-31G(d) level.

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