Showing papers in "Ultrasonics in 1970"

TL;DR: The relationship between the physical characteristics of the signals and the situations in which they are emitted is discussed, together with possible reasons for the use of such high frequency sounds.

TL;DR: In this paper, the growth and critical evaluation of surface acoustic wave (SAW) impedance and propagation properties for certain new single crystal piezoelectric materials are discussed. And it is concluded that bismuth germanium oxide may prove an important cost-effective alternative to both quartz and lithium niobate, and that either zinc oxide or aluminum nitride is destined to prove invaluable in the realization of monolithic circuits such as programmable tapped delay lines, in which SAW will be interfaced with metal-oxide semiconductor (large scale integrated) technology, and active S

TL;DR: In this article, the coupling coefficient of a piezoelectric plate is analyzed for various types of anisotropy, and it is shown that the frequency equation shows that the overtone resonances are not integral multiples of the fundamental.

TL;DR: The elastic and piezoelectric properties of single crystals of paratellurite (TeO 2 ) are investigated in this paper, where the phase velocity of shear waves is independent of temperature.

TL;DR: In this article, a method of depositing thin single crystal piezo-electric transducers of ZnO for converting microwave electromagnetic energy to phonon energy is described, and the effects of varying substrate temperature and vapour pressure on the crystal structure, physical characteristics and electromechanical coupling factor are discussed.

TL;DR: In this paper, it was shown that the yields are dependent only upon the energy deposited, and are completely independent of the frequency, intensity or intensity distribution of the ultrasonic field, and also of the gas content of the solution.

TL;DR: In this paper, the design philosophy behind two different types of tube drawing equipment based upon ultrasonic phenomena is presented, namely, plug-drive and die-drive systems, for commercial, industrial applications.

TL;DR: In this article, a narrow glass capillary has been set into transverse oscillation at 20kHz by being driven from one end, the other end remaining free, and a standing wave field is set up in the glass with characteristics which closely follow predictions based on the theory for flexing rods.

TL;DR: No evidence of blood damage could be detected by in vitro or in vivo tests, and it is suggested that this observation may be related to effects of ultrasound on blood reported by other observers in which blood damage was produced by vigorously vibrating air bubbles.

TL;DR: The development of fetal cephalometry for determining maturity and decrease in fetal growth rate and ultrasound A-scan methods for measuring the fetal skull in utero are discussed with modifications to overcome certain difficulties.

TL;DR: In this paper, the authors used a rotary kiln dryer to accelerate the drying rate of coal fine by using low temperature radiant heat and forced air through the coal bed.

TL;DR: A broad fundamental basis of transducers can be found in this article, where the main purpose is to help users to select the best transducers for their applications and to determine approximately the performance of a transducer when a tentative design is available.

TL;DR: Gas bubbles in the blood are believed responsible for the symptoms of decompression sickness and it is desired to design a system which will detect these bubbles if they appear in the circulation of a man undergoing decompression.

TL;DR: A broad fundamental basis of transducers can be found in this paper, where the main purpose is to help users to select the best transducers for their applications and to determine approximately the performance of a transducer when a tentative design is available.

TL;DR: The fibrous metallic bundles behave sonically similar to propagation of light waves in fibre-optics bundles as discussed by the authors, and the transmission system vastly expands uses of ultrasound to work areas where formerly the size of the driver-motors or ambient conditions limited its use.

TL;DR: In this article, the authors describe a focussing unit which concentrates longitudinal ultrasonic waves internally in a horn constructed with a parabola end, and demonstrate the capability of producing highly stable emulsions having preponderance of 1μm particles.

TL;DR: A modification of a halftone tube with a variable persistance feature is described to standardise the brightness control setting and make the operator scan consistently over the area.

TL;DR: In this article, high-speed photographic studies of droplet formations were made in order to better understand this method of atomization, and experimental results were compared with the theories of standing capillary waves.

TL;DR: In this paper, the physics and the basic theory of the contact-impedance meter were outlined and it was shown, for a variety of surface excitations, how the resonance frequency of an ultrasonic sensor is related to the contact area and to the elastic constants of the test-piece.

TL;DR: Ulasonic absorption spectroscopy is described for investigating the biological and chemical damage caused by gamma irradiation on three solutions, namely erythrocyte solution, sodium salt DNA solution in distilled water and glucose solution in purified water.

TL;DR: In this article, the authors discuss the problem of adapting transducers to withstand ocean bottom pressures, determining more precisely the power limits of piezoelectric ceramics, and developing more powerful mathematical methods for array design.

TL;DR: The CAL Echo-encephaloscope uses an ultrasonic pulse technique to display the midline of the brain through the intact skull, where a midline shift of 1mm or more is significant.

TL;DR: In this article, an anisotropic propagation medium with parallel transmitting and receiving surfaces and equal-spacing gratings was used for the group delay line, which is a transverse elastic mode with elliptical Huygens wavelets in the plane normal to the length direction of the grating lines.

TL;DR: The equipment surveyed included ‘A’ —scopes, ‘B’—scanners, Doppler effect instruments and physiotherapy equipment and typical prices are quoted for all except ’A‘—scopes and characteristics of ultrasonic physiotherapy Equipment are tabulated.

TL;DR: The fundamental piezomagnetic coefficients of Ni-Mn-Co ferrites and Al-Fe alloys were investigated in this paper at room temperature and in the range of magnetic polarisation up to technical saturation.