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The surface structure of GaP(001) has been studied using X-ray photoelectron diffraction (XPD), low-energy electron diffraction (LEED), synchrotron radiation photoemission spectroscopy (SRPES), Auger electron spectroscopy (AES) and scanning tunneling microscopy (STM). It is confirmed that the clean GaP(001) surface prepared by Ar-ion sputtering and annealing (ISA) exhibits a (2×4) reconstruction terminated by gallium. STM images indicate that about 20% of the gallium dimers at the surface are not regularly arranged in the [1 1 0] direction. The surface core-level shifts of Ga 3d and P 2p for the (2×4) surface, as measured by SRPES, suggest that the surface components S1 and S2 correspond to Ga dimers at the surface and Ga atoms with three-fold coordination in the surface region, respectively. The component S3 is also suggested to be due to P atoms with three-fold coordination. Upon adsorption of t-butylphosphine on the (2×4) surface at 350°C, a (2×1) structure is observed by LEED and STM. Based on the above results, models of the GaP(001)-(2×4) and -(2×1) surface structures are proposed.

The electrochemical reduction of nitric oxide (NO) in an aqueous electrolyte was studied using different metal electrodes and gas diffusion electrodes (GDEs). The reduction product selectivity for NO reduction depends strongly on the type of electrode metal. NH3 was produced as the predominant reduction product on Ti, Ni, Cu, and Ag electrodes and N2 was produced predominantly on a glassy-carbon electrode. The current–potential curve in the NO atmosphere depended on the nature of the metal electrode. Product selectivity did not depend on the metal in electrolysis using GDEs. The predominant product was N2O and N2 on GDEs containing Ni, Pt, and Cu electrocatalysts.

The anisotropy of the activation energy of the flux pinning in a La1.85Sr0.15CuO4 single crystal was investigated by ultrasonic measurements in various directions of wave vector κ, polarization vector u and magnetic fields H . The large activation energy of U(0 K, 14 T) = 972 K and small field dependence αH−0.3 were obtained for H || c- plane , when the flux motion is parallel to the c-axis where the intrinsic pinning mechanism due to the layered structure is effective. The elastic modulus of the flux-line lattice which moves parallel to the c-axis is proportional to H 2 cos 2 θ , and the value of U rapidly decreases with increasing tilt angle θ between H and the c-plane (U(θ = 10°) ∼ 300 K, U(θ = 30°) ∼ 75 K). These angular dependences of the elastic modulus and the activation energy can be explained on the basis of the intrinsic pinning mechanism and the three-dimensional stepwise flux-line structure.

The flux line lattice (FLL) elasticity and its anisotropic pinning have been investigated in a single crystalline La 1.85 Sr 0.15 CuO 4 by ultrasonic measurements under high magnetic fields. The depinning activation energies are deduced from measurements under various settings of the directions of wave vector k, polarization vector u and magnetic fields H as U ac (0 K, 14 T) = 972 K for H⊥ c, uc. U ab (0 K, 14 T) = 201 K for H⊥ c, uc × H) and U ca (0 K, 14T) = 25K for Hc, u⊥c. The magnetic field dependence of U are also deduced as U ac ∝ H −0.3 and U ca ∝ H −1.5 . The angular dependence of U ac is discussed on the basis of the intrinsic pinning mechanism.

Solid films of poly (γ-methyl l -glutamate) were prepared by casting solutions in chloroform, dichloromethane, and m -cresol. The mode and amplitude of thermal molecular fluctuations in the crystalline phase were studied by X-ray diffraction. All the films contain α-helical molecules and have hexagonal crystal structures, but differ from each other in their crystallinity and crystallite size. The calculated molecular fluctuation amplitudes also differ considerably. Below a threshold temperature in the range 140°–190°C (different for each sample), the segmental molecular motion is composed of translation along the chain axes coupled with rotation about the axes. At higher temperatures, the structure changes thermoreversibly into a modification, in which a screw-type motion along the α-helix axis is predominant.

The question is raised on the validity of the usual derivation of the Lipkin-Weisberger-Peshkin (LWP) difficulty. It is shown that the LWP difficulty can be derived legitimately in the framework of the Wu-Yang formalism. A non-abelian version of the LWP difficulty is presented in a Wu-Yang solution of the pure SU(2) Yang-Mills theory, showing a failure of the Jacobi identity at one point through the term − i 4π( r ·T)δ 3 (x) . A nonrelativistic treatment of the SU(2) doublet particle with spin 1 2 around this solution is given. Some remarks are made also on a possible LWP difficulty in the 't Hooft-Polyakov monopole.

Various reports have been published on corntrol systems for slab reheating furnaces centering on the theme of energy savings. But, due to the fact that the process description is largely non-linear and hounded with many restrictive conditions no system was formularized in the past that would simultaneously satisfy two targets, minimum deviation in the extracted slab temprature and maximum reheating efficiency. The present control system, however, is a system that satisfies both targets simultaneously. Although it makes us p of experimental laws in part, it provides all the internal characteristics and control laws of the process in formularizerd forms. The system is composed of an observer and predictor to ensure sub-optimization. As for the control method, it is based on feed forward control and is characterized by the fact that control of the fuel distribution to each zone is always directed toward securing Maximum efficiency .