Formation of a nonequilibrium energy distribution over vibrational degrees of freedom of the H2O molecule as water vapor expands in a supersonic nozzle

1992 ◽  
Vol 33 (4) ◽  
pp. 506-514
Author(s):  
A. B. Britan ◽  
V. A. Levin ◽  
A. M. Starik ◽  
A. N. Khmelevskii
Keyword(s):  
Water Vapor ◽  
Energy Distribution ◽  
Degrees Of Freedom ◽  
Supersonic Nozzle ◽  
Nonequilibrium Energy

SUB-keV ATOM INDUCED SPUTTERING OF CONDENSED N2: A MOLECULAR DYNAMICS STUDY

1993 ◽  
Vol 07 (13n14) ◽  
pp. 857-863 ◽  
Author(s):  
HEINO KAFEMANN ◽  
HERBERT M. URBASSEK
Keyword(s):  
Molecular Dynamics ◽  
Energy Distribution ◽  
Time Dependence ◽  
Degrees Of Freedom ◽  
Center Of Mass ◽  
Translational Motion ◽  
Original Position ◽  
Time And Space

By molecular dynamics, the sputtering of a condensed N 2 sample due to 100 eV N atom bombardment is studied. The features observed in general parallel those of previous studies of Ar sputtering. Time- and space-resolved measurements give novel information on the original position of sputtered molecules and the time dependence of their energy distribution. Rotational and vibrational degrees of freedom are underpopulated with respect to center-of-mass translational motion.

ON THE POSSIBILITY OF THE POSTTRANSITION STATE CLASSICAL TRAJECTORY PREDICTIONS OF ENERGY DEPOSITION IN THE REACTION PRODUCTS' DEGREES OF FREEDOM

2020 ◽  
Author(s):  
B. I. Loukhovitski ◽  
◽  
A. S. Sharipov ◽  
Keyword(s):  
Energy Distribution ◽  
Degrees Of Freedom ◽  
Energy Deposition ◽  
Classical Trajectory ◽  
Reaction Products ◽  
Dynamic Simulations ◽  
Bimolecular Reactions

The possibility of applying the method of posttransition state classical trajectory dynamic simulations to study the nascent energy distribution among the molecular degrees of freedom of the reaction products on the example of a number of bimolecular reactions is considered.

scholarly journals Potential of Dual-Frequency Radar and Microwave Radiometer Synergy for Water Vapor Profiling in the Cloudy Trade Wind Environment

2020 ◽  
Vol 37 (11) ◽  
pp. 1973-1986
Author(s):  
Sabrina Schnitt ◽  
Ulrich Löhnert ◽  
René Preusker
Keyword(s):  
Water Vapor ◽  
Information Content ◽  
Degrees Of Freedom ◽  
Microwave Radiometer ◽  
Optimal Estimation ◽  
Cloud Layer ◽  
Trade Wind ◽  
Dual Frequency ◽  
Shallow Convection ◽  
Brightness Temperatures

AbstractHigh-resolution boundary layer water vapor profile observations are essential for understanding the interplay between shallow convection, cloudiness, and climate in the trade wind atmosphere. As current observation techniques can be limited by low spatial or temporal resolution, the synergistic benefit of combining ground-based microwave radiometer (MWR) and dual-frequency radar is investigated by analyzing the retrieval information content and uncertainty. Synthetic MWR brightness temperatures, as well as simulated dual-wavelength ratios of two radar frequencies are generated for a combination of Ka and W band (KaW), as well as differential absorption radar (DAR) G-band frequencies (167 and 174.8 GHz, G2). The synergy analysis is based on an optimal estimation scheme by varying the configuration of the observation vector. Combining MWR and KaW only marginally increases the retrieval information content. The synergy of MWR with G2 radar is more beneficial due to increasing degrees of freedom (4.5), decreasing retrieval errors, and a more realistic retrieved profile within the cloud layer. The information and profile below and within the cloud is driven by the radar observations, whereas the synergistic benefit is largest above the cloud layer, where information content is enhanced compared to an MWR-only or DAR-only setup. For full synergistic benefits, however, G-band radar sensitivities need to allow full-cloud profiling; in this case, the results suggest that a combined retrieval of MWR and G-band DAR can help close the observational gap of current techniques.

scholarly journals Tracking the ultrafast nonequilibrium energy flow between electronic and lattice degrees of freedom in crystalline nickel

2020 ◽  
Vol 101 (10) ◽  
Author(s):  
P. Maldonado ◽  
T. Chase ◽  
A. H. Reid ◽  
X. Shen ◽  
R. K. Li ◽  
...  
Keyword(s):  
Energy Flow ◽  
Degrees Of Freedom ◽  
Nonequilibrium Energy

Experimental Determination of Local Structural Stiffness by Disassembly of Measured Flexibility Matrices

1998 ◽  
Vol 120 (4) ◽  
pp. 949-957 ◽  
Author(s):  
S. W. Doebling ◽  
L. D. Peterson ◽  
K. F. Alvin
Keyword(s):  
Energy Distribution ◽  
Strain Energy ◽  
Degrees Of Freedom ◽  
Cross Sectional ◽  
Linear Least Squares Problem ◽  
Physical Sensor ◽  
Plates And Shells ◽  
Matrix Eigenvalues ◽  
Local Stiffness

A new method is presented for identifying the local stiffness of a structure from vibration test data. The method is based on a projection of the experimentally measured flexibility matrix onto the strain energy distribution in local elements or regional superelements. Using both a presumed connectivity and a presumed strain energy distribution pattern, the method forms a well-determined linear least squares problem for elemental stiffness matrix eigenvalues. These eigenvalues are directly proportional to the stiffnesses of individual elements or superelements, including the cross-sectional bending stiffnesses of beams, plates, and shells, for example. An important part of the methodology is the formulation of nodal degrees of freedom as functions of the measured sensor degrees of freedom to account for the location offsets which are present in physical sensor measurements. Numerical and experimental results are presented which show the application of the approach to example problems.

scholarly journals Discussion on energy distribution in molecules in relation to chemical reactions

1934 ◽  
Vol 146 (857) ◽  
pp. 239-271 ◽  
Keyword(s):  
Energy Distribution ◽  
Finite Time ◽  
Degrees Of Freedom ◽  
Chemical Change ◽  
Velocity Of Sound ◽  
Border Line ◽  
Points Of View ◽  
Solvent Molecules ◽  
Time Required ◽  
Internal Degrees Of Freedom

It often happens that the empirical observations of chemistry reveal the working of principles which can be easily interpreted in terms of physical theories, but which might have been difficult to predict. One need only mention the question of the nature of valency as one of the most conspicuous examples. For this reason it is useful if problems lying on the border line of physics and chemistry are discussed from both points of view. The present theme is the distribution of energy in molecules and its relation to the phenomena of chemical change. We know that the transference of energy from one molecule to another and, in particular, the accompanying interconversion of translational and internal energy depend upon specific mechanisms which give rise to phenomena of great interest. I need only mention the influence of hydrogen and certain other gases in maintaining the energy distribution in unimoleculer reactions, the variation of the velocity of sound with frequency, due to the finite time required for the establishment of equilibrium in the energy distribution among the internal degrees of freedom, and lastly that curious inability of solvent molecules to degrade the light energy absorbed by fluorescent substances.

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