Vibration Spectrum of Copper by Dayal's Secular Determinant

A secular determinant for silver has been set up, in which the ion-ion force constants have been derived from known expressions appearing in the theory of metallic cohesion. The matrix elements have been represented as the sum of three terms. One of these arises from the Coulomb interaction of the ions and has been taken from Kellermann’s work on sodium chloride. The second mainly owes its origin to the exchange forces but includes any effect due to the non-spherical nature of the Fermi surface. It has been calculated from the experimental values of the shear constants after subtracting the electrostatic contribution. The third term is due to the volume forces and has been evaluated by means of two dispersion relations given respectively by de Launay and Bhatia. For this purpose, the bulk modulus for the volume forces has been calculated by Dayal & Tripathi’s method. Vibration frequencies and the specific heats have been calculated separately by the use of both the dispersion relations. Both the theoretical 0-T curves agree with the experimental curve at all temperatures within the accuracy of the calculations.

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Quantum chemical prediction of 2H-pyran vibration spectrum

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19900010 ◽

1990 ◽

Vol 55 (1) ◽

pp. 10-20 ◽

Cited By ~ 7

Author(s):

Stanislav Böhm ◽

Josef Kuthan

Keyword(s):

Vibrational Spectrum ◽

Ab Initio ◽

Quantum Chemical ◽

Vibration Spectrum ◽

Equilibrium Geometry ◽

Heterocyclic Molecule ◽

Vibrational Transitions ◽

Correlation Corrections

Ab initio MO optimalization of the 2H-pyran molecule leads to a defined equilibrium geometry of this so far not identified heterocyclic molecule and to a physical justification of its existence. More advanced nonempirical wavefunctions and temperature corrections indicate that heterocyclic molecule I is energetically less stable than non-cyclic isomers II and III. Wavenumbers of fundamental vibrational transitions of heterocycle I and also known (2E)-2,4-pentadienal (IIIb were calculated using 3-21 G wavefunctions. The vibrational spectrum of compound I is predicted on the basis of correlation corrections.

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Fault Diagnosis of BLDC Motor Drive using Vibration Spectrum Analysis: Part II

2020 IEEE International Power and Renewable Energy Conference ◽

10.1109/iprecon49514.2020.9315236 ◽

2020 ◽

Author(s):

Vivek Kumar Sharma ◽

Adil Usman ◽

Bharat Singh Rajpurohit

Keyword(s):

Fault Diagnosis ◽

Spectrum Analysis ◽

Vibration Spectrum ◽

Motor Drive ◽

Bldc Motor

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Vibration Analysis of a Screw Pump Unit

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.753-755.1727 ◽

2013 ◽

Vol 753-755 ◽

pp. 1727-1730

Author(s):

Yue Zhang ◽

You Hong Xiao ◽

Jun Weng ◽

Wan You Li

Keyword(s):

Mathematical Method ◽

Vibration Analysis ◽

Vibration Spectrum ◽

Vibration Response ◽

Fe Model ◽

Force Response ◽

Pump Unit ◽

Surface Integral ◽

Screw Pump

In this paper, the vibration of a three screw pump was studied. Firstly the vibration response of the pump was tested. Then the FE model of the pump was constructed and the modals of it were calculated. The exactness of the result was confirmed by the testing modals and the reasonable of the FE model was verified at the same time. Finally, the force acted on rotors due to pressure was calculated by the mathematical method of surface integral. The force was loaded on the FE model and the force response was predicted, which represented the basic vibration of the screw pump. Based on the work above, the vibration spectrum of the screw pump was analyzed.

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High-resolution measurement of the infrared rotation-vibration spectrum of the negative molecular ionNH−14

Physical Review A ◽

10.1103/physreva.35.1099 ◽

1987 ◽

Vol 35 (3) ◽

pp. 1099-1112 ◽

Cited By ~ 17

Author(s):

Mohammad Al-Za’al ◽

Harold C. Miller ◽

John W. Farley

Keyword(s):

High Resolution ◽

Vibration Spectrum ◽

High Resolution Measurement ◽

Resolution Measurement

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Global Least-Squares Analysis of the IR Rotation–Vibration Spectrum of HCl

Journal of Chemical Education ◽

10.1021/ed082p150 ◽

2005 ◽

Vol 82 (1) ◽

pp. 150 ◽

Cited By ~ 2

Author(s):

Joel Tellinghuisen

Keyword(s):

Least Squares ◽

Vibration Spectrum

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Modeling the Effects of Underwater Detonation Wave

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.588.175 ◽

2013 ◽

Vol 588 ◽

pp. 175-183

Author(s):

Andrzej Grządziela

Keyword(s):

Vibration Spectrum ◽

Water Environment ◽

Underwater Explosion ◽

Impulse Loading ◽

Structure Model ◽

Measuring Systems ◽

Shaft Line ◽

Hull Structure ◽

On Line ◽

Vibration Measuring

Minehunters are subjected to specific sea loads due to waving and dynamical impacts associated with underwater explosion. Sea waving can be sufficiently exactly modeled by means of statistical methods. Much more problems arise from modeling impacts due to underwater explosion. Knowledge of a character of impulse loading which affects ship shaft line can make it possible to identify potential failures by means of on-line vibration measuring systems. The problem of influence of sea mine explosion on hull structure is complex and belongs to more difficult issues of ship dynamics. Underwater explosion is meant as a violent upset of balance of a given system due to detonation of explosives in water environment. A paper presents a proposal of identification of a degree of hazard the ships hull forced from underwater explosion. A theoretical analysis was made of influence of changes of hull structure in vicinity of hull. The main problem of naval vessels is a lack of dynamical requirements of stiffness of the hull. Modeled signals and hull structure were recognized within sensitive symptoms of three sub models: model of hull structure, model of impact and model of propulsion system. All sub models allow testing forces and their responses in vibration spectrum using SIMULINK software and FEM models.

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