Ultrasound and health

EL ‘PINBR,

I. B.,

and

!RJ3KOL ‘mcov,

FAVORVA,

et al. re!hxation hl nomr poiydloxaBts. J. Acoust. Sot. Amer., 35, No. 4, p. 481 (1963) Ultrasonic measuremen ts of relaxational effects have been obtained in ten homogeneous linear polysiloxane liquids (silicones) and in a number of heterogeneous mixtures of them, in the frequency range from 30 MC/S to 270 MC/S. Velocity and absorption, and variations of absorption with velocity, frequency and temperature, with special emphasii on the six and ten atom fluids, are illustrated by numerous graphs. (11 figures, 2 tables, 23 references) (Ultrasonics 1963, abstract 129) I-nnamt,

L. I.

Priroda, I, p. 100 (1963) Investigations carried out at the Institute of Biophysics of the Academy of Sciences, U.S.S.R., on the action of ultrasound on the molecules of various proteins, particularly insulin, are briefly described. Frequencies of 800 kc/s at 10-12 W/cm’ are mentioned. It emerges that the presence of gases in the solution subjected to the action of ultrasound determines the effectiveness of insulin and the nature of the chemical by-products. (Ultrasonics 1963, abstract 124) In6alinand-.

0. A.

and besIlt.h. Okkrana truah i sotsial’noe strakhovenie, 6, No. 1, p. 33 (1963) The author briefly describes some of the dangers of highpower ultrasonic applications which are known to cause adverse effects on the peripheral nervous system and also to affect the hearing sensitivity. Sound isolating installations are suggested as a possible solution but where the operator has to be in contact with the cleaning fluids, special gloves with air cavities or made from layers of material of different acoustic impedances are recommended, as ordii gloves do not afford sulIicient protection. A protection device for the ears called the Antiphone is also described. (2 8gures) (Ultrasonics 1963, abstract 125) tlbammd

1. L.,

tJhmaic

KOSSOFF,

0.

design of narrow heamwidth m. J. Acoust. Sot. Amer., 35, No. 6, p. 905 (1963) The design of weakly focusing transducers is outlh& and a theoretical analysis for determii the best shape of transducer and the off-axis Geld is given. A computer programme was used for determimng the optimum dimensions of the transducer and the result shows a marked improvement in the beamwidth and better aximuthal reeolution. (12 figures, 3 tables, 18 references) (Ultrasonics 1963, abstract 130) Tbe

LANGE~CKER, in rockets

CJOODMAN, J. E., IJltmmb

and

in the

HILTON,

K. A.

textile indwtry. The Dyer, 129, No. 11,

p. 759 (1963) After a brief introduction to the subject a number of methods of generation of ultrasonic energy are described and in particular the Rapisonic liquid whistle, which is already widely used. The authors critically review both potential and established uses in the textile industry. The various stages of processing of textiles are described and the effects produced by ultrasound are analysed. At present substantial economies are achieved in time and materials in the preparation of solutions and emulsions in many stages of textile processing, but laundering and cleaning of fabrics is not an economical proposition. (8 figures, 4 references) (Ultrasonics 1963, abstract 126) B.

testiog and ilight safety. Rlight InternationaZ, 83, No. 2817, p. 330 (1963) A brief description of the principles underlying ultrasonic testing and their application to testing aircraft components. Fatigue is the greatest problem, particularly in highly stressed military aircraft, and the advantages of ultrasonic testing techniques are that tests can be carried out in situ often in places inaccessible by other methods. (5 figures) (Ultrasonics 1963, abstract 127) Ultrpswie

HOLMES, 8. betmiow of austedtk atainkm steel. Appl. Mat. Res., 2, No. 3, p. 181 (1963) Stainless steel products always present difficulties and inconsistencies in flaw detection, which are mainly accounted for by their anisotropic characteristics and large grain size. The grain size in certain diions approaches the ultrasonic wavelength at the working frequency, might produce gram resonance, and is therefore responsible for the extremely high attenuation which cannot be removed by heat treatment. The work was carried out at the University of Nottingham under contract to the Central Electricity Generation Board but the author does not suggest any defhrite remedies or proposals for overcoming these problems. (7 figures, 3 references) (Ultrasonics 1963, abstract 128) IJltmmic

md

msRfetyf8ctoM missi@

A.Z.A.A. Journal, I, No. 1, p. 80

(1963) The author reports experimental results of investigations carried out to de&mine the effect of sonic and ultrasonic vibrations on various metals. The results show clearly that the static yield stress necessary for plastic deformation of materials subjected to vibration is reduced by up to 40%. Tbe effects prove to be independent of the temperature and frequency up to l-5 MC/S, but are linearly related to amplitude of vibration, which suggests dependence on hysteresis rather than relaxation effects. The extension apparatus and instruments are illustrated together with a number of graphs of the results, and the author stresses the catastrophic etfects that might occur by ignoring the concentration of standing waves. (7 figures, 12 references) (Ultrasonics 1963, abstract 131) LELE,

HARRIS-MADDOX,

B.

Tbeeffectofr?dcd~-

P. P.

Theeffectsof feeused rdtraaenkrrrBktion ~~periPhs=I nerves, with ohservathnts on Iecal heating. &per. Neural., 8, No. 1, p. 47 (1963) This is a comprehensive report on the effect of ultrasotmd at a number of frequencies on the nerve conduction of cats, monkeys and man. Both continuous wave and pulsed radiation at dilferent intensities were studied, mainly on dissected nerves, but a number of experiments in situ are also described. The author concludes that the effects of ultrasonic radiation on the peripheral nervous system are mainly thermal in origin, and although it is possible to block nerve conduction reversibly by ultrasound, the margin of safety is too narrow to justify its use.(53 references, 13 figures, 1 table) (Ultrasonics Z%3, abstract 132) MANNING,

0.

radar gddea the bhd. Design and componentk in engineering, p. 33 (April 1963) A wmprehensive description of a remarkable new approach to the problem of blind guidance. To cope with the octave frequency sweep a capacitana microphone has been developed which can even provide liited information about the nature of the obstacle. A modified spectacle frame with transducers inserted in place of lcsn?es could house the complete system. The author begins with the sentena “If bats can do it, why not us? and ends with the description of a number of possible additional applications. (11 figures) (Ultrusonics 1963, abstract 133) ultrasonic

uLnusoNIcs/October-December

1963

ABsTRAcrs

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