Time-dependent damping effect for the dynamics of DNA transcription

The temperature-dependence of proton electric conductivity in hydrogen-bonded molecular systems with damping effect was studied. The time-dependent velocity of proton and its mobility are determined from the Hamiltonian of a model system. The calculated mobility of (3.57–3.76) × 10-6 m 2/ Vs for uniform ice is in agreement with the experimental value of (1 - 10) × 10-2 m 2/ Vs . When the temperature and damping effects of the medium are considered, the mobility is found to depend on the temperature for various electric field values in the system, i.e. the mobility increases initially and reaches a maximum at about 191 K, but decreases subsequently to a minimum at approximately 241 K, and increases again in the range of 150–270 K. This behavior agrees with experimental data of ice.

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Effect of the Baffle on the Asymmetric Gravity-Jitter Excited Slosh Wave and Spacecraft Moment and Angular Momentum Fluctuations

Proceedings of the Institution of Mechanical Engineers Part G Journal of Aerospace Engineering ◽

10.1243/pime_proc_1993_207_254_02 ◽

1993 ◽

Vol 207 (2) ◽

pp. 105-120

Author(s):

R J Hung ◽

C C Lee ◽

F W Leslie

Keyword(s):

Angular Momentum ◽

Dynamic Behaviour ◽

Time Dependent ◽

Viscous Force ◽

Wave Excitation ◽

Rotating Fluids ◽

Damping Effect ◽

Solid Interface ◽

Interface Geometry ◽

Effect Of Surface

The dynamic behaviour of fluids affected by asymmetric gravity jitter oscillations, in particular the effect of surface tension on partially-filled rotating fluids in a dewar tank, with and without installing baffle-board, imposed by time-dependent directions of background gravity have been investigated. Results show that lower frequency gravity jitter imposed on the time-dependent variations of the direction of background gravity induced a greater amplitude of oscillations and a stronger degree of asymmetry in liquid–vapour interface geometry than that made by the higher frequency gravity jitter. As the viscous force, between liquid and solid interface, greatly contributes to the damping effect of slosh wave excitation, a rotating dewar installed with baffles provides more area of liquid-solid interface than a rotating dewar without baffles. Results show that the damping effect provided by the baffles reduce the amplitude of slosh wave excitation, lowers the degree of asymmetry in the liquid–vapour distribution, and lowers angular momentum and fluid moment fluctuations.

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