Showing papers in "Ultrasonics in 1972"

TL;DR: A 32-element cathetertip system specially developed for instantaneous study of moving cardiac structures based on the sonar-type phase-corrected circular array techniques is described and it is shown that such a catheter can be constructed.

TL;DR: The method is based on the use of a transducer with a central perforation canal, through which the puncture or biopsy needle can be introduced and a discussion is provided of the advantages and uncertainty involved.

TL;DR: Methods to improve the grey scale, sensitivity and resolution of ultrasonic echograms are described and Typical echogram in obstetrics, ophthalmology and of the breast are used to illustrate the improvements obtained by the use of these techniques.

TL;DR: Doppler blood-flow transducers have been used to detect gas bubbles in the circulatory system during hyperbaric decompression but in vivo experiments indicate that it would be difficult to obtain any correlation between the output of these transducers and bubble size.

TL;DR: There is a lack of commercial interest in these atomizers in fields of application where they are better than conventional atomizers, partly due to poor communication of the available information, part due to the knowledge that outstanding features on small scale devices might not be retained on larger units, and partly because of present day capital cost of the electrically driven units.

TL;DR: In this paper, a tutorial review of the theory of the simple thickness mode piezoelectric transducer is given, showing what basic assumptions are made, and which material constants must be used in the equations.

TL;DR: A survey of the principles, parameter values and classes of AMF's and their tradeoffs with digital matched filters (DMF's) when viewed in the context of future systems applications, employing many codes and operating bandwidths in excess of several MHz.

TL;DR: In this article, the use of sonic power to produce permanent effects in a treated medium has been discussed, and the effects generally require very high powers for their initiation, hence the usage of term macrosonics.

TL;DR: In this article, a theory which explains the effects of dispersion and coagulation in a cavitating liquid medium is proposed on the basis of a study of the interaction mechanism of a cavitation bubble and a particle of the material medium.

TL;DR: In this article, a description of the physical nature of ultrasonic welding and of the influence of the process variables on weld quality is given, and the functions and properties of the constituent parts of the system are reviewed.

TL;DR: In this article, a method for obtaining reproducible measurements of the degree of cleaning and the effects of various parameters on the ultrasonic cleaning process is described, in particular, the relations between the energy density, the electrical power supplied to the ultrasonically excited tanks, and the level of cleaning efficiency.

TL;DR: A commercial ultrasonic tester has been used to assess the application of ultrasonics in ceramic research and testing and it has proved possible to follow and assess frost damage in wall tiles.

TL;DR: In this paper, a general system of difference-differential equations for the amplitudes of the diffracted lightwaves caused by an ultrasonic wave and its first n −1 harmonics is established.

TL;DR: A miniature pulser-preamplifier was developed to fit the transducer holder and its characteristics proved superior to most devices in common use.

TL;DR: The requirements of foetal biparietal diameter measurement are discussed, and a new design of electronic caliper described, which provides digital indication and simultaneous marker identification on both A and B displays.

TL;DR: In this article, the general relationships of strength, elasticity and hardness are examined, and the value in these relationships of data obtained by ultrasonic techniques on flaw-detection, grain-size measurement, and elasticity (especially those quantities for anisotropic metals) and the use of the ultrasonic hardness indicator.

TL;DR: In this article, the use of a sweep frequency acoustic cavity resonator for the measurement of absorption and velocity of sound in liquids in the frequency range 200 kHz to 30 MHz is described.

TL;DR: A Doppler ultrasound probe has been used to monitor the foetal heart during childbirth in an attempt to simplifyfoetal cardiotachometry.

TL;DR: In this article, a combination of the liquid borne acoustic generator with "static mixer modules" may help to overcome the drawback that acoustic generators cannot produce the same size of dispersed particles as those produced by ultrasonic emulsifiers using velocity transformers.

TL;DR: Statistical evidence is presented which suggests that as the ultrasound beam traverses the optical components of refraction, increased variability in depth and amplitude measures occur.

TL;DR: The characteristics affecting the performance of scanning sonars are examined in the light of experience gained so far and the circuit arrangements employed and the processing leading to the final modulating voltages are outlined schematically.