Changes in spectral shapes of metallic surface composition obtained from stainless steel, stainless steel after heat-treatment at 900°C in atmosphere, stainless steel after hydrogen introduction and stainless steel after heat-treatment by boiling water were observed by soft X-ray appearance potential spectroscopy. Stainless steel 304 surface seems to be covered by an oxidation layer of chromium and iron before sputtering and annealing. However, the surface layer observed after sputtering and annealing cycles consisted of pure chromium and iron. The peak ratio of Fe/Cr increases with sputtering and annealing. Hardly any change in spectral shapes of stainless steel after heat-treatment at 900°C was observable by sputtering and annealing cycles. Changes in spectral shapes of stainless steel after heat-treatment by boiling water were the same as stainless steel without treatment. The Mn spectra of stainless steel were clearly observed only after hydrogen introduction, as compared with other forms of treatment.
The oxidation of polyethylene by partial discharge is supposed to proceed by two main processes: the vaporization of the sample film by activated oxygen (e. g. atomic oxygen) resulting in a decrease in weight, and a rather moderate oxidation by ozone resulting in an increase in weight. The ozone is formed by the reaction of molecular oxygen with the activated oxygen atom which is produced by partial discharge in air. The process mentioned above was examined by the flow method. The polyethylene film near the point of the partial discharge in air was consumed by the activated oxygen, and on the other hand, the film remote from the discharging point exhibited a weight increase. The results showed the validity of the two processes mentioned above. The concentration of activated oxygen decayed exponentially with time, the life time being about 0.1 sec at 7 Torr and inversely proportional to the ambient pressure. The life time at atmospheric pressure in air was extrapolated to be 1 msec approximately. The reaction rate of polyethylene with the activated oxygen is about one-hundred times greater than that with ozone. From the pressure dependence of the life time of the activated oxygen, it is suggested that a two-body collision process is predominant in the formation of the ozone.
The motion of an edge dislocation in the stress field given by superposing many stress components due to the size effect of solute atoms is examined by computer simulation on the basis of the string model, The moving process at 0K is followed by a relaxation method and some discussions are made on the yield stress in relation to the width of model crystal, the line tension, the Peierls stress and the deviation from Hooke's law in the vicinity of solute atoms. In addition, the thermally activated motion is analyzed by a shooting method which is applied to obtain the stable and saddle-point configurations of a dislocation. The yield stress of KCl-17 mol% KBr single crystals below 350K is explained by this thermal activation process and the applicability of this mechanism to the plateau is briefly discussed.
Following a detailed discussion on the optical properties of the lamellar grating, the construction and performance of a lamellar grating Fourier spectrometer designed for submillimeter and millimeter spectroscopy is described. The grating consists of 18-cm-square metal plates each with a thickness of 9mm. An arc-stabilized high pressure mercury lamp is used for the radiation source, and a Ge bolometer or an InSb hot electron photoconductor for the detector. Absorption spectra of solids, high resolution gaseous absorption spectra and the measured refractive indices of several crystals are presented. Measurement is easily done in the spectral range below 30cm-1. Resolution of 0.025cm-1 and accuracy of wavenumber within ±0.003cm-1 are obtained.
A pulse-operated polarized H ion source of Lamb-shift type has been developed at the National Laboratory for High Energy Physics in Japan (KEK) for acceleration of polarized protons in KEK 12 GeV proton synchrotron. The new principle proposed by B. L. Donnally has been adopted, in which transitions of hyperfine-structure substates of 2 S1/2 state to those of 2P1/2 state are induced by an RF electric field in a weak magnetic field. A theoretical investigation for this principle is carrried out to find the optimum condition for transitions and shows that the RF electric field should make an angle of about 50° with the direction of the static magnetic field. Details of various elements and performance of the polarized ion source are also described. In the preliminary experiments, 350 nA H- beam of about 60% polarization has been obtained.
The microwave response of stripline coupled Josephson junctions were investigated for sputtered Nb-NbOx-Pb tunnel junctions. Microwave-striplines were fabricated using evaporated SiO films as dielectric layers and evaporated Pb films as ground electrodes. It was found that when one junction used as a microwave generator was biased at the voltage of self-induced steps on its I-V char acteristics, microwave induced steps were observed on the I-V characteristics of the other junction which was used as a detector. The result of this experiment shows their potential use as microwave generators and detectors.