Stretch-Induced Cavitation: How Critical Cavity Radius and Barrier Energy, Radius, and Energy of a Stable Cavity Depend on the Stretching Factor

2021 ◽  
Author(s):  
Max L. Berkowitz
Keyword(s):  
Cavity Radius ◽  
Barrier Energy ◽  
Stretching Factor ◽  
Stable Cavity

scholarly journals Catalyzed Ethanol Chemical Looping Gasification Mechanism on the Perfect and Reduced Fe2O3 Surfaces

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1663
Author(s):  
Laixing Luo ◽  
Xing Zheng ◽  
Jianye Wang ◽  
Wu Qin ◽  
Xianbin Xiao ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Reaction Mechanism ◽  
Density Functional ◽  
Oxygen Carrier ◽  
Catalytic Decomposition ◽  
Density Functional Theory Calculations ◽  
Chemical Looping ◽  
Functional Theory ◽  
Barrier Energy ◽  
Gasification Technology

Biomass chemical looping gasification (CLG) is a novel gasification technology for hydrogen production, where the oxygen carrier (OC) transfers lattice oxygen to catalytically oxidize fuel into syngas. However, the OC is gradually reduced, showing different reaction activities in the CLG process. Fully understanding the CLG reaction mechanism of fuel molecules on perfect and reduced OC surfaces is necessary, for which the CLG of ethanol using Fe2O3 as the OC was introduced as the probe reaction to perform density functional theory calculations to reveal the decomposition mechanism of ethanol into the synthesis gas (including H2, CH4, ethylene, formaldehyde, acetaldehyde, and CO) on perfect and reduced Fe2O3(001) surfaces. When Fe2O3(001) is reduced to FeO0.375(001), the calculated barrier energy decreases and then increases again, suggesting that the reduction state around FeO(001) favors the catalytic decomposition of ethanol to produce hydrogen, which proves that the degree of reduction has an important effect on the CLG reaction.

Feasible tuning of barrier energy in PEDOT:PSS/Bi2Te3 nanowires-based thermoelectric nanocomposite thin films through polar solvent vapor annealing

Nano Energy ◽  
2020 ◽  
Vol 67 ◽  
pp. 104207 ◽  
Author(s):  
Wan Sik Kim ◽  
Gopinathan Anoop ◽  
Il-Seok Jeong ◽  
Hye Jeong Lee ◽  
Hyun Bin Kim ◽  
...  
Keyword(s):  
Thin Films ◽  
Polar Solvent ◽  
Solvent Vapor ◽  
Barrier Energy ◽  
Nanocomposite Thin Films ◽  
Vapor Annealing ◽  
Solvent Vapor Annealing

Study on Cavity Growth in Uniaxial Tension of ZK60 Magnesium Alloy

2007 ◽  
Vol 353-358 ◽  
pp. 687-690
Author(s):  
Yan Dong Yu ◽  
De Liang Yin ◽  
Bao You Zhang
Keyword(s):  
Volume Fraction ◽  
Cavity Growth ◽  
Experimental Studies ◽  
Superplastic Forming ◽  
Cavity Radius ◽  
Analysis Software ◽  
Mixed Characteristic ◽  
Substantial Growth ◽  
Zk60 Magnesium Alloy ◽  
Electronic Microscope

Cavity growth is a typical microstructure feature in superplastic forming (SPF) of materials. Substantial growth and interlink of cavities in superplastic deformation usually lead to reduction in elongation, even to failure. Consequently, it is necessary to investigate the mechanism and model of cavity growth. In this paper, experimental studies on cavity growth were carried out by means of superplastic tension of ZK60 magnesium alloys. Scanning electronic microscope (SEM) was employed for observation of fractography. Experimental cavity radius and volume fraction were determined by optical microscopy and corresponding picture-based analysis software. It is found that, the fractured surfaces after a superplastic elongation have a mixed characteristic of intergranular cavities and dimples. Further, the cavity growth is identified to follow a exponentially increasing mode.

Shear waves from a nuclear explosion in a salt cavity

1968 ◽  
Vol 58 (6) ◽  
pp. 2043-2051
Author(s):  
William R. Perret
Keyword(s):  
Particle Velocity ◽  
Nuclear Explosion ◽  
Shear Waves ◽  
Vertical Motion ◽  
Salt Dome ◽  
Explosive Source ◽  
Level Plane ◽  
Stable Cavity

ABSTRACT Shear waves have been resolved in records of acceleration and particle velocity resulting from the Sterling event which was a nuclear explosion (380 tons) within the stable cavity left by the Salmon detonation in the Tatum salt dome. These shear waves were strongest in records of vertical motion at stations in the shot-level plane, but were detectable in records from both vertical and horizontal radial gages above and below that elevation. No appreciable shear waves could be identified in records from shot-level gages oriented horizontally. All instruments involved in this study were situated within the salt dome at ranges between 166 and 660 meters from the explosive source. Shear waves carried over 95 per cent of the energy in vertical shot-level records, but they represented less than 11 per cent of the energy in horizontal radial shot-level records. Cause of the vertically polarized shear waves is considered to be vertical asymmetry at the source.

scholarly journals Electronic Effect on the Molecular Motion of Aromatic Amides: Combined Studies Using VT-NMR and Quantum Calculations

Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2294 ◽  
Author(s):  
Sungsoo Kim ◽  
Jungyu Kim ◽  
Jieun Kim ◽  
Daeun Won ◽  
Suk-Kyu Chang ◽  
...  
Keyword(s):  
Aromatic Compounds ◽  
Density Functional ◽  
Electronic Effect ◽  
Variable Temperature ◽  
Rotational Barrier ◽  
Amide Bond ◽  
Theoretical Research ◽  
Quantum Calculations ◽  
Amide Bonds ◽  
Barrier Energy

Rotational barrier energy studies to date have focused on the amide bond of aromatic compounds from a kinetic perspective using quantum calculations and nuclear magnetic resonance (NMR). These studies provide valuable information, not only regarding the basic conformational properties of amide bonds but also the molecular gear system, which has recently gained interest. Thus, we investigate the precise motion of the amide bonds of two aromatic compounds using an experimental rotational barrier energy estimation by NMR experiments and a theoretical evaluation of the density functional theory calculation. The theoretical potential energy surface scan method combined with the quadratic synchronous transit 3 method and consideration of additional functional group rotation with optimization and frequency calculations support the results of the variable temperature 1H NMR, with deviations of less than 1 kcal/mol. This detailed experimental and theoretical research strongly supports molecular gear motion in the aromatic amide system, and the difference in kinetic energy indicates that the electronic effect from the aromatic structure has a key role in conformational movements at different temperatures. Our study provides an enhanced basis for future amide structural dynamics research.

scholarly journals Highly parallel ultra-fast random number generation from a stable-cavity broad-area semiconductor laser

2021 ◽  
Author(s):  
Kyungduk Kim ◽  
Stefan Bittner ◽  
Yongquan Zeng ◽  
Stefano Guazzotti ◽  
Ortwin Hess ◽  
...  
Keyword(s):  
Semiconductor Laser ◽  
Random Number ◽  
Random Number Generation ◽  
Broad Area ◽  
Number Generation ◽  
Stable Cavity

Elastic displacement of primary waves from explosive sources

1964 ◽  
Vol 54 (3) ◽  
pp. 947-959 ◽  
Author(s):  
Joseph W. Berg ◽  
George E. Papageorge
Keyword(s):  
Fourier Transform ◽  
Natural Frequency ◽  
Nuclear Explosion ◽  
Fractional Power ◽  
Elastic Displacement ◽  
Cavity Size ◽  
Velocity Range ◽  
Cavity Radius ◽  
Pressure Function ◽  
Long Period

Abstract Equations derived from Blake's (1952) model of diverging waves from a point source were programmed for computer analysis. Variations of the displacement resulting from changes in the pressure function, propagational velocity, range, and cavity size were investigated. Results of the research indicate that: (1) a step pressure function used with this model gives displacements that closely approximate the displacements measured at 0.4 km from the Gnome nuclear explosion; (2) near the source, long-period displacements are inherent with this model; (3) the periods of the maximum Fourier transform amplitude of the radiation field is proportional to the equivalent cavity radius; (4) the peak displacements scale to the two-thirds power of charge size for values of a between 80 (0.5 kt) and 600 m (275 kt); and (5) between 0.1 and 3.0 cps, the amplitudes of given frequencies scale to the first power of charge size for values of a between 145 (3 kt) and 305 m (28 kt). In general, Fourier amplitudes at frequencies below the natural frequency of the cavity scale to the first power of charge size, and Fourier amplitudes at frequencies above the natural frequency of the cavity scale to a fractional power of charge size. It is suggested that this may be a good model with which to compare near-source observations of seismic phenomena.

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