Infra-red spectra of flavanones and flavones. Carbonyl and hydroxyl stretching and CH out-of-plane bending absorption

1962 ◽  
Vol 18 (7) ◽  
pp. 939-957 ◽  
Author(s):  
L.H. Briggs ◽  
L.D. Colebrook
Keyword(s):  
Infra Red ◽  
Out Of Plane ◽  
Plane Bending

The effect of intermolecular forces upon the vibrations of molecules in the crystalline state I. The out-of-plane bending of the carbonate ion in aragonite minerals

1963 ◽  
Vol 275 (1362) ◽  
pp. 295-309 ◽  
Keyword(s):  
Intermolecular Forces ◽  
Absolute Intensities ◽  
Carbonate Ion ◽  
Nearest Neighbours ◽  
Bending Mode ◽  
Infra Red ◽  
Out Of Plane ◽  
Plane Bending ◽  
Oxygen Bond ◽  
Dipole Energy

The infra-red absorption of polycrystalline BaCO 3 , SrCO 3 , and CaCO 3 , the latter in both the aragonite and calcite modifications, has been measured in the region 600 to 2000 cm -1 . Absolute intensities were determined for each of the three fundamental bands of the carbonate ion, by the method of extrapolation to infinite dilution of the carbonate in the alkali halide matrix. The band due to the out-of-plane bending mode was examined under high resolution, the samples employed having been enriched to a 50/50 ratio of 12 C/ 13 C. Intermolecular coupling in this band, which is revealed by the isotopic solid solution, has been interpreted as arising primarily from interaction of the dipoles produced during the vibration. The dipole derivatives calculated from this coupling agree fairly well with those estimated from the absolute intensities. Various sources of error are discussed, and in particular, an estimate is made of the dipole-dipole energy summed over the entire lattice, instead of merely for nearest neighbours. The carbon-oxygen bond moment during the vibration has an effective value of from 1.3 to 1.7 debyes.

Intensities in the infra-red spectrum of benzene

1956 ◽  
Vol 238 (1213) ◽  
pp. 245-255 ◽  
Keyword(s):  
Dipole Moment ◽  
Experimental Error ◽  
Carbon Skeleton ◽  
Absolute Intensities ◽  
Bond Stretching ◽  
Infra Red ◽  
Out Of Plane ◽  
Plane Bending ◽  
The Absolute

The absolute intensities of the infra-red active fundamental vibrations of benzene, mono-deuterobenzene, and para -dideuterobenzene have been measured and interpreted in terms of the dipole moment derivatives: ∂ μ z /∂ S 11 = -1·43 D/Å; ∂ μ y /∂ S 18 a = - 0·51 D/Å; ∂ μ y /∂ S 19 a = -0·32 D/Å; ∂ μ y /∂ S 20 a = -0·78 D/Å. All three spectra are consistent with these values. The ‘effective’ C—H bond moment for in-plane bending is 0·31 D and for out-of-plane bending 0·61 D. The value for the C—H bond-stretching dipole-moment derivative is 0·45 D/Å with the H atom becoming less positive as the bond stretches. In-plane distortions of the carbon skeleton which leave the C—H bond directions unchanged, produce zero dipole moment within the experimental error.

Comparison of Failure Modes of Piping Systems With Wall Thinning Subjected to In-Plane, Out-of-Plane, and Mixed Mode Bending Under Seismic Load: An Experimental Approach

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Izumi Nakamura ◽  
Akihito Otani ◽  
Masaki Shiratori
Keyword(s):  
Dynamic Behavior ◽  
Failure Modes ◽  
Seismic Load ◽  
Piping System ◽  
Shake Table ◽  
Shake Table Tests ◽  
Wall Thinning ◽  
Piping Systems ◽  
Out Of Plane ◽  
Plane Bending

Pressurized piping systems used for an extended period may develop degradations such as wall thinning or cracks due to aging. It is important to estimate the effects of degradation on the dynamic behavior and to ascertain the failure modes and remaining strength of the piping systems with degradation through experiments and analyses to ensure the seismic safety of degraded piping systems under destructive seismic events. In order to investigate the influence of degradation on the dynamic behavior and failure modes of piping systems with local wall thinning, shake table tests using 3D piping system models were conducted. About 50% full circumferential wall thinning at elbows was considered in the test. Three types of models were used in the shake table tests. The difference of the models was the applied bending direction to the thinned-wall elbow. The bending direction considered in the tests was either of the in-plane bending, out-of-plane bending, or mixed bending of the in-plane and out-of-plane. These models were excited under the same input acceleration until failure occurred. Through these tests, the vibration characteristic and failure modes of the piping models with wall thinning under seismic load were obtained. The test results showed that the out-of-plane bending is not significant for a sound elbow, but should be considered for a thinned-wall elbow, because the life of the piping models with wall thinning subjected to out-of-plane bending may reduce significantly.

Stresses in Curved, Circular Thin-Wall Tubes

1963 ◽  
Vol 30 (1) ◽  
pp. 134-135
Author(s):  
E. A. Utecht
Keyword(s):  
Thin Wall ◽  
Bending Moments ◽  
Circular Tubes ◽  
Out Of Plane ◽  
Thin Walled ◽  
Plane Bending

Curves are presented which give stress intensification factors for curved, thin-walled circular tubes under various combinations of in-plane and out-of-plane bending moments.

Out-of-Plane Bending (Opb) Test of Large Diameter Mooring Chains

2021 ◽  
Author(s):  
m.r. Karimi ◽  
J. Braun ◽  
E. Gooijer ◽  
P. Barros ◽  
E. Carlberg ◽  
...  
Keyword(s):  
Large Diameter ◽  
Out Of Plane ◽  
Plane Bending
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