The deuterium spin-lattice relaxation time, 7",, of H 2 0 /D 2 0 mixtures is measured at 298.2 K. The relaxation rate, Ff 1 , is found to increase with increasing deuterium atom fraction, n, the plot of T\ 1 vs. n exhibiting a small depature from linearity. A general equation Tf 1 (n) for the H 2 0 / DiO system is formulated. The temperature dependence of Tx is investigated in the temperature r...

A light-beam-assisted temperature-control system operating within a temperature range from 77 to 180 K is developed for investigating the absorption of electromagnetic waves by high-temperature superconductors in the vicinity of superconducting transition with an ESR spectrometer. The advantage of this system is the feasibility of modulating the temperature of a sample with a frequency of 80 Hz...

A modified form of the relaxed weak temperature gradient (WTG) approximation is described and implemented in a cloud resolving model. In this scheme, the vertical heating profile is spectrally decomposed into normal modes. The relaxation time scale of each mode is set proportional to the corresponding vertical wave number of the mode, as would be expected if gravity waves were responsible for t...

We investigated temperature distribution in a solid state nuclear magnetic resonance (NMR) sample rotor under magic angle spinning (MAS) experiments by analyzing the (207)Pb chemical shift of solid lead nitrate (Pb(NO3)2). The analysis corrected a mismatch of the temperature dependence of (1)H spin-lattice relaxation time (T1(H)) obtained from different sample positions in the rotor. We prepare...

Substitution of Li for Cu in La2Cu12xLixO4 donates holes; at x ­ 0.5 the Li ions form an ordered superlattice which isolates individual CuO4 plaquettes from one another, and the number of doped holes is sufficient that each plaquette is occupied. Above 170 K, an activated temperature dependence of the Cu nuclear spin relaxation rate reveals a magnetic excitation of the doped-hole state with an ...

springs are the  mechanical parts which have many application in industries. static and dynamic forces cause relaxation in these parts so that they lose some of their free length and reaction force. springs constant are very important in airplane and vailway industry since constant and variable forces are applied to them in period time, therefore it is necessary to avoid decreasing in spring co...

The problem treated here is to determinethe viscosity effect on stresses, temperature change and chemical potential in a circular plate. The mathematical formulation is applied to two theories of thermoelastic diffusion developed by Sherief et al. [27] with one relaxation time and Kumar and Kansal [9]with two relaxation times. Laplace and Hankel transform techniques are used to obtain the expre...

A form of the weak temperature gradient (WTG) approximation, in which the temperature tendency and advection terms are neglected in the temperature equation so that the equation reduces to a diagnostic balance between heating and vertical motion, is applied to a two-dimensional nonlinear shallow-water model with the heating (mass source) parameterized as a Newtonian relaxation on the temperatur...