The low field spin-lattice relaxation time T_1ρ of protons has been calculated in the rotating frame considering the effect of the quantum rotation of NH₄-ion. The weak collision case i.e. γH_Lτ_r<<1 has been treated, where H_L is the local dipolar field and τ_r the correlation time. The transition rates were calculated by using the phenomenological model of Clough and Punkkinen. It is shown that the temperature dependence of T_1ρ Shows a frequency independent minimum clearly when Λ₀>>γH₁, which is in agreement with the experimental results, where Λ₀ is the tunneling frequency of NH₄-ion and H₁ the strength of rf field. Since the frequency independent minimum is easy to observe, the measurement of T_1ρ is useful to determine the tunueling frequency of NH₄-ion.

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We performed the measurements of the dynamic heat capacity of aqueous solutions of lysozyme and α-chymotrypsin near heat denaturation by using an ac calorimeter. The obtained values of the ac enthalpy and the ac entropy at the heat denaturation process were much smaller than those measured by usual dc calorimeters. This fact tells us that the main part of the dynamic denaturation process takes place at a frequency lower than our measuring frequency of 0.6 Hz, in consistent with the results given by T-jump experiments. Furthermore, it was clarified by a circular dichroism measurement that the disulfide bridges play an important role in holding the three-dimensional structure of the proteins.

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The spatial correlation functions between the tangential and normal unit vectors along the chain contour are derived in the continuous elastic chain model to discuss the persistence vector of the chain and the model is reduced to a simpler one, in which only two characteristic lengths appear in the results, when the chain contour runs perpendicular to the third principal axis of each section of the chain.

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A new model is proposed for the polyelectrolyte solutions in order to explain their dynamical behavior. The electrolytic solvent is assumed to be decomposed into the ordinary viscous fluid and a charged fluid superposed on it. Each of the polymer molecules dissolved into these two fluids is represented by a point-charge distribution {τ_αi} on i-th segment in α-th chain. The charge τ_αi=1 or 0 is treated as a stochastic variable. It is assumed that the two fluids are independent of each other when any electric matter is absent in the solvent and that they are coupled only via charged polymers. Dynamical equations of these three constituents are set up in a self-consistent manner. Edwards and Freed’s theory is used to solve them.

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We have applied a dynamical model for polyelectrolyte solutions proposed in I of the present series to derive the polymer viscosity. In the infinite dilution limit, the stationary intrinsic viscosity increases from the ordinary value for the non-electrolytic solutions to infinity. Its increase is (1−τ)⁻² for small τ which is the average of the charge distribution {τ_αi} related to the degree of electrolytic dissociation and 0≤τ≤1. From the ω-dependence of the intrinsic viscosity, it is found that a new “internal” viscosity is induced. Further, we calculate the concentration dependence of the reduced viscosity in rather dilute solution. There, the similar enhancement is also found. These are caused by the rapid response without delay of the charged fluid to the point charges attached to the polymers.

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The (100) solid-liquid coexistent state and the interface are studied by a molecular dynamics method for the soft-core system with the pair potential φ(r)=ε(σ⁄r)¹². To reduce computing time damping and random forces satisfying the fluctuation-dissipation theorem are applied to each atom during equilibration of the system. Transition parameters are obtained rather easily. which are in agreement with other works. This means, however, that monitoring transition parameters is not enough for judging to what degree a simulated state is approaching to a coexistent equilibrium state. The interface is not very stable and proceeds or recedes according to local density and temperature fluctuations. Therefore, averaged features depend on time intervals over which time averages are taken. An apparently large thickness of the interface observed for a LJ system is interpreted in this way. Feasibility of simulating crystallization process is also shown.

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The nonlinear stabilities of resistive MHD modes are investigated in a tokamak configuration by a three dimensional MHD simulation based on a rectangular column model under the fixed boundary condition. The m=1 internal resistive kink mode is excited for the central safety factor, q₀<1, resulting in a sawtooth oscillation of temperature. Only the m=2 mode is excited for q₀<2 and a small resistivity. On the other hand, the several modes of (−m : n)=(2 : 1), (1 : 1) and (3 : 2) appear for q₀<2 and a little large resistivity depending on the q-configuration through the variation of toroidal current. The (3 : 2) mode plays an important role on the mode coupling between the (1 : 1) and (2 : 1) modes. As the result, the (2 : 1) mode finally determines the stability and stable configurations of plasma are formed with the condition of q\gtrsim2.

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The amplitude oscillation of a nonlinearly generated second harmonic wave is studied both experimentally and theoretically. Not only a fundamental but also a small amplitude second harmonic signal is applied to the exciter. The spatial wavepatterns are found to depend on the initial phase of the second harmonic. The amplitude oscillation disappears under certain conditions and the fundamental and second harmonic waves propagate as if they were independent of each other.

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When a circular cylinder performs the saw-toothed oscillations, the induced steady streaming is the sum of the circulatory streaming due to the sinusoidal oscillations and an additional flow. The additional flow is approximately unidirectional in the direction of oscillation, and its velocity increases with the increase of S, but is independent of D, where S=ωs²⁄v, D=ωd²⁄v, ω is the angular frequency of the cylinder motion, s the oscillation amplitude, v the kinematic viscosity of the working fluid and d the diameter of the cylinder.

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The direct method of calculating the multi-periodic wave solutions by Nakamura are applied to the following equations; the Korteweg-de Vries equation, the Toda equation, the Sawada-Kotera equation and the model equation for shallow water waves, and are obtained three-periodic wave solutions expressed in terms of Riemann’s θ-function. All parameters determining the characters of the wave are obtained numerically.

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Since helicity was found to be time-invariant in inviscid flows, equilibrium states of inviscid, incompressible, homogeneous turbulence have obtained a much variety in the form of energy spectrum, etc. In fact, the energy equipartition does not coexist with non-zero helicity. In this paper, a simple numerical investigation to clarify this fact is presented. The time-evolution of three-dimensional random flow velocity fields, with truncated wave components and initially set with some net helicity, is pursued in a computer until the spectrums of velocity variance, helicity, etc. reach a steady state in a certain coarse-graining sense. The results evidently support the known theory.

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