Quantum electronics has also contributed useful techniques to astrophysics, and the future development in astronomy in the microwave and infrared will probably be very much affected by developments in quantum electronics which affect the detection and processing of radiation. Astronomical observations have shown that maser-type amplification occurs naturally in clouds of water and of hydroxyl radicals. These, and possibly certain astro-nomical sources of high intensity infrared radiation, offer a new experimental realm and theoretical challenges to those interested in coherent radiation processes. Various important astronomical phenomena at microwave and infrared wavelengths are discussed, along with some of the technical developments needed for their careful study.
Principles of operation of the cyclotron are briefly described. Present status of nature of beams accelerated by the cyclotron is given, and compared with beams produced by other accelerators. Expected improvements on energies and energy spreads of beams necessary for usage for nuclear physics are explained. Present typical applications for nuclear physics and other fields, solid state physics, chemistry, biology and medicine, are described.
A rapid, interferometric method for measuring the drunkenness of thread on a lead screw that involves no mechanical contact with the thread is described. The moving plane mirror of a Michelson interferometer is set on the axis of the lead screw. The lead screw is mounted on the carriage of a machine which moves it parallel to its axis. Fringes produced through the Michelson interferometer are changed into a train of electric pulses. These pulses drive a pulse motor which rotates the lead screw such as to move it in the opposite direction to the carriage movement, through a suitable reduction gear train. The movement of thread images is sensed by photoelectric microscopes with a deflecting glass plane and the lead errors and drunkenness are recorded by an associated electric circuit. The performance of the apparatus is persented.
The thermal dissociation of hydrocarbon molecules on a hot tungsten emitter results in the appearance of dark (334) planes. Between the elapsed time to needed for the appearance and the pressure P of methane, the following relation was found: log to=-μ log p+α where μ ranges from 0. 828 to 4. 7 4 depending upon tip temperatures; and the change of μ with the tempera-ture is not monotonous. This dependence of μ on the temperature can be explained by considering that (1) the mean residence time of methane molecules on the tungsten surface has to be long enough for the dissociation of these molecules, by mutual bonding of each molecule: (2) μ is the mean number of molecules making the mutual bonding; (3) vibrational energy levels of methane are involved, in a resonance-like manner, with its dissociation.
The influence of an external magnetic field on the magnetization reversal of ferrite core was investigated. Switching speed of ferrite core is found to increase by applying an external magnetic field. In a low drive magnetic field region, a transverse output which corresponds to an uniform rotation mode is observed by applying an external magnetic field. This fact shows the existence of a mixture of magnetization reversal modes under external magnetic field, viz. an uniform rotation superposed on domain wall motion or on nonuniform rotation as the case may be. The ratio of magnetization by the uniform rotation mode to total magnetization reversal is about 2 or 3% at drive magnetic field=30.0 Oe and external magnetic field=45.0 Oe. GILBERT equation as the equation of motion of magnetization reversal was adopted and output waveforms by magnetization reversal are calculated under appropriate condition and are compared with experimental results.
An experiment to construct the hologram of an object in water using ultrasonic waves (1 MHz) and to reconstruct the original images using laser light (6328 Å) is conducted. Scanning the detector mechanically, ultrasonic holograms are constructed by Gabor's coherent background method and an electronic reference method. As the directivity of the source is an important problem in ultrasonic holography, experimental study is conducted. From the reciprocity theorem in sound fields, the same hologram as is made by scanning the detector is obtained by scanning the source. This is the specific way of the scanning method. Further, it is proposed to apply ultrasonic holography to interferometry and basic experiments are made. From these experiments, it is made clear that ultrasonic holography is a promising method of non-destructive testing.
One of the nematic liquid crystals operating at room temperature, N-(p-methoxybenzy-lidene)-p-n-butylaniline, was synthesized and its electro-optic effect was measured; (1) trans-mittance vs. applied field characteristics, (2) V-I characteristics, (3) transient and stationary responses of optical transmission in AC and DC field. Simultaneously its domain behavior was observed by a polarization microscope. It was concluded that the mechanism of the electro-optic effect in nematic liquid crystals can be explained by two modes, i. e. the static orientation mode at low electric field and the dynamic scattering mode (DSM) at high electric field. Also clear accounts were given of the difference in them.
Important factors for evaluating MOS stru-cture, namely, density of interface charge, density of interface state, dispersion factor of time constant and conductance-bias characte-ristic, are investigated by a bias temperature treatment. It is found that, the density of interface state is increased in the case of negative BT treatment, but in the positive case, decreased, independent of interface charge. These behavior of interface states can be explained by a tunneling model. The experimentally observed distribution of inter-face state density versus energy is found to be correlated with the conductance-bias curve, and the peak density is obtained at an energy level about 0. 25 eV above the valence band edge for 0.9Ω-cm P-type Si.