Line strength factors for E,F1Σ+g(v′ = 0, J′ = J′′) – X1Σ+g (v′′, J′′) (2 + 1) REMPI transitions in molecular hydrogen

2004 ◽  
Vol 82 (6) ◽  
pp. 723-729 ◽  
Author(s):  
Andrew E Pomerantz ◽  
Florian Ausfelder ◽  
Richard N Zare ◽  
Winifred M Huo
Keyword(s):  
Experimental Determination ◽  
Molecular Hydrogen ◽  
Line Strength ◽  
Chem Phys ◽  
Rotational States ◽  
Calculated Line ◽  
Hot Filament ◽  
Theoretical Results ◽  
Line Strengths

Experimentally and theoretically determined line strengths are presented for E,F1Σ+g(v′ = 0, J′ = J′′) – X1Σ+g (v′′, J′′) (2 + 1) REMPI transitions in H2, HD, and D2. The experimental technique employs a hot filament source of internally excited hydrogen that allows experimental determination of line strengths for the low rotational states of highly excited vibrational manifolds (v′′ ≤ 4). The line strengths are found to depend only weakly on J′′ for the states measured here, and theoretical results indicate that the line strengths depend strongly on v′′. These values are combined with previously measured and calculated line strengths for these transitions (K.-D. Rinnen, M.A. Buntine, D.A.V. Kliner, R.N. Zare, and W.M. Huo. J. Chem. Phys. 95, 214 (1991)), resulting in a more complete compilation of REMPI line strengths for molecular hydrogen. Key words: hydrogen, spectroscopy, REMPI, line strength, multiphoton.

Experimental Determination of Line Strengths for Selected Carbon Monoxide and Carbon Dioxide Absorption Lines at Temperatures between 295 and 1250 K

1994 ◽  
Vol 48 (11) ◽  
pp. 1442-1450 ◽  
Author(s):  
Patrick J. Medvecz ◽  
Kenneth M. Nichols
Keyword(s):  
Fourier Transform ◽  
High Temperature ◽  
Absorption Spectra ◽  
High Temperatures ◽  
Room Temperature ◽  
Theoretical Calculations ◽  
Line Strength ◽  
Temperature Data ◽  
Line Strengths

Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO2 absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the P branch of the fundamental absorption band (2150–1950 cm−1) while the CO2 vibrational-rotational lines were from the far wing of the R branch of the v3 fundamental band (2395–2380 cm−1). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO2/N2 gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for distortions resulting from the finite resolution of the spectrometer and for peak overlap. Line strength measurements were made from the corrected peaks by using the Bouguer-Lambert law and assuming a Lorenztian line profile. The experimentally obtained line strengths were evaluated (1) by statistical calculations, (2) by consideration of the validity of the Bouguer-Lambert assumption for these data, (3) by comparison with existing room-temperature and high-temperature data, and (4) by comparison with theoretical calculations. For CO, the statistical analysis suggests that the reported values have an uncertainty of ±10–12%, which is similar to the observed discrepancies with other reported values at room temperature. At high temperatures, the difference between these data and previously reported data and theoretical predictions is less than 10%. For CO2, the statistical uncertainty associated with the line strength calculations is less than 5%, which is also the approximate level of agreement with existing room-temperature data. For lines with m indicies of 65–89, at high temperatures, the values reported in this work agree within 5 to 10% of theoretical calculations.

Experimental determination of molecular hydrogen solubilities in liquid fluorocarbons

1992 ◽  
Vol 37 (4) ◽  
pp. 423-426 ◽  
Author(s):  
Maria L. Japas ◽  
Chien Ping Chai Kao ◽  
Michael E. Paulaitis
Keyword(s):  
Experimental Determination ◽  
Molecular Hydrogen

Experimental Determination of the Roller Chain Load Distribution

1983 ◽  
Vol 105 (3) ◽  
pp. 331-338 ◽  
Author(s):  
M. R. Naji ◽  
K. M. Marshek
Keyword(s):  
Experimental Study ◽  
Experimental Determination ◽  
Elastic Properties ◽  
Load Distribution ◽  
Noticeable Effect ◽  
Roller Chain ◽  
Chain Link ◽  
A Chain ◽  
Theoretical Results

An experimental study was conducted to determine the effect of elastic properties, geometric variations, and lubrication on roller chain load distribution. Comparison was made with the theoretical results for a test chain on a 20-tooth sprocket. The load distribution was found for a large number of cases to be independent of the elastic properties of the chain and the sprocket. The load distribution for the chain on a driver sprocket differed from that for a chain on a driven sprocket because of the change in direction of the friction force. Lubrication had no noticeable effect. A large pitch for the sprocket teeth was found to amplify the tension in the chain link.

Experimental Determination of Vibration Parameters Required in the Statistical Energy Analysis Method

1983 ◽  
Vol 105 (3) ◽  
pp. 337-344 ◽  
Author(s):  
B. L. Clarkson ◽  
R. J. Pope
Keyword(s):  
Experimental Determination ◽  
Analysis Method ◽  
Coupling Loss ◽  
Structural Components ◽  
Indirect Methods ◽  
Vibration Parameters ◽  
Theoretical Results ◽  
Dissipation Loss ◽  
Loss Factors

In the high frequency range of vibration the Statistical Energy Method provides one of the most convenient ways of estimating vibration levels in structural components. The dynamic characteristics of the structure are described in terms of the modal densities, dissipation loss factors and coupling loss factors of the component parts. Theoretical and semiempirical results are available for some typical components. This paper describes the development of indirect methods for the experimental determination of these three parameters. Where theoretical results are available the experimental results show reasonable agreement. The results of tests on a range of components are described.

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