Showing papers by "Waseda University published in 1969"

Real Time Control of System Voltage and Reactive Power

Abstract: This paper presents a centralized optimizing computational algorithm for the on-line control of voltage and reactive power. The body of the paper is divided into two parts.

Gross Theory of Nuclear β-Decay

Abstract: A theory for the gross properties of the nuclear a-decay is developed. In order to treat the gross features, summations over final states are replaced by integrations, and the average of the squared absolute value of the nuclear matrix element times the final level density Cthis quantity is denoted by IMaCE) \2 where -E is the decay energy) is investigated instead of individual matrix elements. First, the general slowness of the allowed a-decay is qualitatively demonstrated by the use of sum rules. Next, a model is set up in order to make quantitative calculations. In this model, an existence of "single-nucleon energies E" is assumed, and each nucleon is assumed to make a "transition" with probability DQ CE, E) as a result of the opera­ tion of the single-particle a-decay operator. IMaCE) 12 is given as an integral with respect to E, whose integrand is the product of DaCE, E) and the distribution function of nucleons over E. Some interference effects are neglected, and the exclusion principle is introduced not in the integrand but in the lower limit of the integration domain. The half-lives of allowed a-decays are calculated with this model. At first, the Fermi gas model is used to evaluate the ene;gy distribution of the single-nucleons. With some trial forms of Da CE, E), a reasonable agreement with experiment is obtained for odd-mass nuclei, especially for nuclei with high Q-values. Secondly, the even-odd mass difference is taken into account in a simplified way to refine the treatment of even-mass nuclei. The results show that the majority of allowed a-decays can be explained to a considerable degree by the gross theory which is utterly dif­ ferent from current theories of a-decay.

Computer Studies on the Approach to Thermal Equilibrium in Coupled Anharmonic Oscillators. II. One-Dimensional Case

Abstract: One-dimensional anharmonic lattices with quadratic as well as quartic potentials between nearest neighbors are treated on computer to see the long-time behaviors of the vibration. As is the case of two-dimensional lattice, the induction period is found to exist and its length increases on decreasing the anharmonic coupling constant. The possible existence of the critical value of the anharmonic coupling constant is surmised, below which the system is almost periodic. Above this critical value, the system tends to reach a thermal equilibrium, which is confirmed by the long-time averages of the squares of the velocities and by the products of velocities of different particles. The significance of the errors introduced during computation for the ergodic property of the system is pointed out.

Effect of prolactin on the tadpole tail fin. I. Stimulatory effect of prolactin on the collagen synthesis of the tadpole tail fin.

Abstract: Bovine prolactin stimulated the growth of connective tissues both in the tail fins and in other regions of the tadpole tail. Correlated with the morphological effect of the hormone on the tadpole tails, protein synthesis in tail fins was promoted about 2 times by prolactin. Experiments performed to determine the kind of protein, the synthesis of which was stimulated by prolactin, revealed that the hormone specifically enhanced collagen synthesis about 40 folds as compared to untreated animals.

Spectral Distribution of the Light Scattered from Rodlike Macromolecules in Solution

Abstract: Rodlike macromolecules in solution undergo translational and rotatory Brownian motions. These motions are not independent, since the translational mobility is anisotropic, and the components are orientation-dependent. By taking this fact into consideration, the space-time correlation function of density is calculated to obtain the spectral intensity of the Rayleigh scattered light. Extra terms are found to exist in the expression of spectral intensity in addition to the main term which comes from the translational and rotatory diffusions assumed independent of each other. This may provide a method to measure separately the principal values of the mobility tensor of rodlike macromolecule.

Normal and Abnormal Absorption Coefficients of X-Rays

Abstract: The normal and the abnormal absorption coefficients of X-rays due to the Compton scattering and the thermal diffuse scattering (TDS) are calculated numerically by taking into account the temperature effect. It is found that effects of both scatterings are comparable for light atoms such as Al and Si, and that the effect of the latter is larger than the former for heavier atoms.

The Correction of the Mean Inner Potential in Electron Diffraction

Abstract: The corrections of the mean inner potential, or the scattering factor of 0-th order V 0 due to plasmon excitation and phonon excitation are calculated on the basis of the 2nd order perturbation theory. It is shown that the contribution of the plasmon excitation becomes large in low energy electron diffraction. Numerical calculations are performed for Si and Al.

Alteration by neonatal hypothyroidism of the critical period for the induction of persistent estrus in the rat.

Abstract: The effects of hypothyroidism for a short period of postnatal life on the induction of persistent estrus by androgen were investigated in female rats of 10 and 13 days of age. Hypothyroidal new born rats produced by feeding propyl thiouracil (PTU) to the mother rats, were more succeptible to the persistent-estrus inductive influence of androgen than normal and thyroxine-therapied hypothyroidal rats of the same age.It is concluded that the period during which androgen exerts a persistent-estrus inductive influence was prolonged in hypothyroidal rats, possibly as the result of the retardation of development of the hypothalamic region, the site affected primarily by androgen.

Exciton States in Synthetic Polynucleotides

Abstract: Singlet exciton states double stranded homopolynucleotides and copolynucleotides are determined within the framework of Frenkel exciton model taking into account the effect of configuration mixing between different exciton states. Interbase interactions are taken into account up to the distance of the order of 15 A and they are calculated directly using the generalized charge densities in the base pairs previously obtained by the authors. The exciton states of model DNA is also discussed in which two kinds of base pairs are arranged in random order. Generally the oscillator strength associated with the lowest exciton states decreases by the effect of configuration mixing. There can be found no weak π→π * transition near 280 mµ in poly (A–U) and copoly \(\left(\begin{array}{c}\text{U--A}\\ \text{A--U}\end{array}\right)\). In a model DNA the absorption intensity in the long wave length side of the main absorption band depends linearly on G–C content.

Granular Localization of Corticotropin-Releasing Activity in Horse Hypophysial Stalk Homogenate

Abstract: A granular fraction, which contained vasopressin and corticotropin releasing factor (CRF), was separated by both differential and sucrose concentration gradient centrifugations from the horse hypophysial stalk. It was first demonstrated that CRF is present in association with granules in the hypophysial stalk as well as vasopressin. However, it is not known at the present time whether CRF and vasopressin are contained in the same or different granules.

π-Electronic Structures of the Base Pairs of DNA

Abstract: π-electronic structures of the base pairs of DNA are determined in the framework of Frenkel-Davydov's exciton theory including double excitations. The π-electron densities in the ground and the excited states and he excitation energies and oscillator strengths are discussed in comparison with those of the component bases. The hyperchromic effect is found in the transition to the lowest excited states and the slight blue shift in A-U pair and somewhat appreciable blue shift in G-C pair are found. Further, the interaction energies between pairing bases are estimated in terms of generalized charge densities of component bases which were calculated using the best available π-electron molecular orbitals obtained in our previous work. The π-electronic stabilization energy of base pairs mainly results from the interaction between the permanent charges in the atomic sites of the bases and it is found that G-C pair is more stable than A-U pair.

Effect of Electron Source to Energy Resolution in Electron Velocity Analysis — Interpretation of Boersch Effect

Abstract: In 1954, Boersch [1] reported that a width of the emission spectrum of an electron beam increases with the beam current or the current density. Those experiments were carried out by a retarding potential analyzer at a beam energy of 30 kV. Later, similar experiments were repeated by several workers with using energy analyzers of various type [2–4]. All those workers agreed that the velocity distribution was broadened so that the effective cathode temperature might be as high as 3 × 104 °K, i.e. at least ten times the real temperature.

Electron Spin Density and Internal Conversion Process

Abstract: We have studied a possibility to explore the spin density of orbital electrons by utilizing the spin dependence of internal conversion processes. We have calculated the relative intensity of internal conversion electrons for the case where the radial wave functions of the orbital electrons are different for spin up and spin down. As a particular example, we have studied the internal conversion process in the decay of the 14.4 keY level of Fe57, using the radial wave functions of the orbital electrons of Fe obtained in the unrestricted Hartree-Fock method which have a reasonable fit to the experimental data on the internal magnetic field. It is shown that the Lr and Mr conversion electrons distribute almost isotropically, and the intensity of con­ version electrons should change by about 0.5% for LI and 2% for MI for different spin polarizations.

On the Molecular Mechanism for Light Capture in Rhodopsin and Phytochrome Systems

Abstract: The light-absorbing mechanisms of the fundamental systems of trigger-photoreception in animals and plants are discussed, on the basis of our calculations performed in the last several years. It is examined that chromophores of rhodopsin and phytochrome are conveniently isolated from other chromophoric groups in order to utilize light as a trigger not as an energy source, and the models for possible photoisomerizations of a non-cyclic tetrapyrrole are presented. The roles of the conformational changes of chromoproteins and of the specific interaction between a chromophore and its associated protein moiety in the cooperative excitation of the systems are also discussed, and it is shown for the case of thermal equilibrium states that the cooperativity can be brought forth from the flexible configurational state of chromophore (indicating that the state is affected by the surrounding chromoproteins through the conformational changes and the specific interaction).

Exciton Band Structures in Polypeptides

Abstract: The singlet and triplet states of π-electrons in peptide group are first determined such that the ASMO-SCF-CI calculation including all the possible configurations can reproduce the observed wavelength of optical absorption maximum. It is shown that the doubly-excited configurations make a non-negligible contribution to the electronic states. Next, in terms of the Frenkel-Peierls method, the singlet and triplet exciton bands for both the H-bonded and the main polypeptide-chains in the two β-structures and in the α-helix are calculated to the second-order perturbation. It is shown that the exciton band structures are dependent only on the sorts of peptide-chains but non on the conformations, and that the interaction between bands does not exert any important effect on the structures.