Oraevsky A.A., Karabutov A.A., Solomatin S.V., Savateeva E.V., Andreev V.G., Gatalica Z., Singh H., Fleming R.D. «Laser optoacoustic imaging of breast cancer in vivo» Акустика неоднородных сред. Ежегодник Российского акустического общества. Труды научной школы проф. С.А. Рыбака. Вып. 2, с. 102 (2001)

Gavrilov L.R. «Improvement of the performance of high-intensity linear and spherical phased arrays for application in surgery» High intensity acoustic waves in modern technological and medical applications. Joint Workshop of Russian Acoustical Society (RAS) and French Acoustical Society (SFA). Special Session of the XVI Meeting of Russian Acoustical Society (Moscow. 14–18 November 2005), с. 111-119 (2005)

Disadvantages of powerful phased arrays designed for noninvasive surgery include the unwanted presence of grating lobes and other secondary intensity maxima in acoustic fields. Methods for improvement the quality of the acoustic fields generated by the arrays are discussed and the efficacy of these approaches is illustrated by the results of measurements and computer modeling. For linear arrays, it was shown that optimization of number of active elements with the values of aperture, focal distance, shift of the focus and other focusing conditions permits to reduce the level of secondary maxima. For two dimensional spherical phased array, it was shown that randomization of elements distributions on the surface of the array improved significantly the performance of the arrays by suppressing grating lobes in the acoustic field. The other necessary condition is that the diameter of circular elements of the array should not be larger than 5 wavelengths. The sparseness of the random array should be within a range, approximately, 40–60%. Randomization increased essentially the ability of the array to steer the single focus or the multiple foci (for example, 25 foci) off the array axis. The parameters and characteristics of random spherical arrays for application in surgery are discussed.

Lafon C., Gelet A., Cathignol D., Prat F., Chapelon J.Y. «Interstitial and intracavitary therapeutic ultrasound» High intensity acoustic waves in modern technological and medical applications. Joint Workshop of Russian Acoustical Society (RAS) and French Acoustical Society (SFA). Special Session of the XVI Meeting of Russian Acoustical Society (Moscow. 14–18 November 2005), с. 30-35 (2005)

The non invasive nature of High Intensity Focused Ultrasound (HIFU) for thermal ablation of in-depth tumors is very promising and several medical devices are currently commercially available. Techniques using intracavitary or interstitial applicators have been proposed because extracorporeal HIFU techniques are not always suitable for deepseated tumors. Bones or gaseous pockets may indeed be located in the intervening tissue. The objective is to bring the ultrasound source as close as possible to the target through natural routes in order to minimize the effects of attenuation and phase aberration along the ultrasound pathway. Under these circumstances, it becomes possible to use higher frequency, thus increasing the ultrasonic absorption coefficient and resulting in more efficient heating of the treatment region. In contrast to extra-corporeal applicators, the design of intracavitary probes imposes additional constraints relative to size and ergonomy. When associated to modern imaging modalities, these minimally invasive therapeutic devices offer very promising options for cancer treatment.

Catheline Stefan, Tanter Mickael, Gennisson Jean-Luc, Fink Mathias «Nonlinear propagation of shear waves in soft solids» High intensity acoustic waves in modern technological and medical applications. Joint Workshop of Russian Acoustical Society (RAS) and French Acoustical Society (SFA). Special Session of the XVI Meeting of Russian Acoustical Society (Moscow. 14–18 November 2005), с. 81-85 (2005)

Transient elastography has shown its efficiency to map the elastic properties of soft tissues. Now like other elastic imaging techniques (sonoelastography or magnetic resonance elastography) transient elastography is faced to the following problem: in order to properly discriminate tumors, additional information such as viscosity, anisotropy or nonlinearity is needed. If nonlinearity has long been studied in metals, crystals or rocks, only a few experimental works are found in the literature concerning soft tissues and none on shear waves. Thanks to the ultrafast scanner that can map the displacement field of shear waves, we present in this paper an overview of three experiments that allow to illustrate and quantify the nonlinear behavior of soft tissue phantoms. In the first one, a static stress is applied on an Agar-gelatin based sample. The change on the shear wave speed characterizes the nonlinear elastic Landau moduli (A = 50 kPa, B = 7 GPa, C = 11 GPa). The surprising difference found between these constants are thought to be closely related to the huge difference between the linear Lame coefficients (λ>>μ). It is the acoustoelasticity experiment. In the second one, we present an experimental observation of a shock shear wave. The very weak Young’s modulus of the tissue phantom allows one to generate plane shear wave with a Mach number as high as unity. In this extreme configuration, the agreement with the numerical simulation of the modified Burgers equation is remarkable. It is the finite-amplitude shear wave experiment. At last, the interaction between two plane transverse waves with frequencies ω1 and ω2 is carefully studied. Harmonics and secondary waves are created during the propagation at the frequencies (3ω1, 3ω2, ω1+2ω2, ω1–2ω2, ω2+2ω1, ω 2–2ω1). It is the nonlinear interaction experiment. The nonlinear coefficients deduced from the two latter experiments are comparable to the order of magnitude of the Landau coefficients found from the first experiment.

Goursolle T., Dos Santos S., Vander Meulen F., Haumesser L., Bou Matar O. «Ultrasonic parametric imaging of metallic samples using nonlinear acoustic measurements» High intensity acoustic waves in modern technological and medical applications. Joint Workshop of Russian Acoustical Society (RAS) and French Acoustical Society (SFA). Special Session of the XVI Meeting of Russian Acoustical Society (Moscow. 14–18 November 2005), с. 120-128 (2005)

A calibrated contact phase modulation method [Vila M., Vander Meulen F., Dos Santos S., Haumesser L. and Bou Matar O. Contact phase modulation method for acoustic nonlinear parameter measurement in solid // Ultrasonics 2004, V.42(1-9) P.1061–1065] have been developed in the laboratory. Nonlinear effects coming from parametric interaction of an high and a low frequency waves can be measured as a phase modulation of the HF acoustic beam. According to the NDE needs, the nonlinearity in samples with interfaces, coming from aeronautic industries (two layers of aluminum bonded by an epoxy thin layer), must be measured. In order to meet these needs, our method has been extended. Thanks to additional measurements of reflection coefficient, calibration procedure, based on the selfreciprocity principle applied to the LF transducer, has led us to obtain absolute value of the LF particle velocity at the bonded interface. To know the feasibility of this extension, preliminary results of nonlinear parameter have been obtained in bi-layer samples considering the propagation inside the layer only. An image has been created by slope values of phase modulation obtained from 25 regularly spaced measurements.

Gurbatov S.N., Egorychev S.A., Kurin V.V., Pronchatov-Rubtsov N.V., Kustov L.M. «Experimental investigation of an acoustic field radiated by a parametric antenna in longitudinally inhomogeneous waveguides» Труды научной конференции по радиофизике, посвященной 80-летию Нижегородского государственного университета им. Н.И.Лобачевского. 7 мая 1998 г., с. 96 (1998)

The results of laboratory researching in to propagation of low-frequency waves generated as linear, and parametrical antenna in shallow homogeneous and inhomogeneous in thickness hydroacoustic waveguides are described. As a model of grounds in the experiment either aluminum plates lying on a rubber substrate or a rubber substrate were used. Waveguides with a similar ground are described within the framework of Pekeris model.

Gurbatov S.N., Enflo B.O., Pasmanik G.V. «Сравнение корреляционных характеристик прямого и обратного рассеяния на пузырьковых слоях» Научная конференция по радиофизике, посвященная 95-летию со дня рождения М.Т. Греховой Нижний Новгород 7 мая 1997 г. Тезисы докладов, с. 86 (1997)

The base of one-dimensional Burgers’ equation with infinitely small viscosity the quantitative and qualitative analyses of the time evolution of pulses with complex structure are performed.

Gurbatov S.N., Mainardi F., Moshkov A.Yu., Tampieri F. «Density distribution in a turbulent flow with strong friction» Труды (пятой) научной конференции по радиофизике, посвященной 100-летию со дня рождения А.А. Андронова. 7 мая 2001 г., с. 230-231 (2001)

Gurbatov S.N., Demin I.Yu., Pronchatov-Rubtsov N.V. «The use bispectral analysis for nonlinear diagnosis of soft tissues» High intensity acoustic waves in modern technological and medical applications. Joint Workshop of Russian Acoustical Society (RAS) and French Acoustical Society (SFA). Special Session of the XVI Meeting of Russian Acoustical Society (Moscow. 14–18 November 2005), с. 100-104 (2005)

The evolution of higher-order spectral functions of random waves propagating in a nonlinear medium are investigated. The possibility of recovering the input spectrum from the measured spectrum and bispectrum at the output of the nonlinear medium is discussed. A method of measurement of nonlinear propagation characteristics of low frequency vibration in the tissues by using bispectral analysis has been described.

Penelet G., Gusev V., Lotton P., Bruneau M. «Experimental and theoretical studies of nonlinear saturation processes in annular thermoacoustic prime movers» High intensity acoustic waves in modern technological and medical applications. Joint Workshop of Russian Acoustical Society (RAS) and French Acoustical Society (SFA). Special Session of the XVI Meeting of Russian Acoustical Society (Moscow. 14–18 November 2005), с. 65-74 (2005)

The present study gives a simplified analytical description of spontaneous generation and finite amplitude saturation of sound in annular thermoacoustic engines, and also provides comparison with experiments. The model includes the description of thermoacoustic amplification of sound (induced by interaction between an heterogeneously heated stack of solid plates and resonant gas oscillations), which accounts for the details of the temperature distribution in the whole thermoacoustic device. The saturation of the acoustic wave amplitude is described by taking into account both the reverse influence of the acoustic field on the temperature field, and the dissipation of acoustic power due to higher harmonics generation and minor losses (vortex generation). From the comparison between simulation results and experiments, it is demonstrated that the dynamical behavior observed in our experimental device is predominantly controlled by the effects of acoustic streaming and acoustically enhanced thermal conductivity tending not only to reduce the externally imposed temperature gradient along the stack, but also to change the shape of the temperature field in such a way that additional thermoacoustic amplification may occur.

Зайцев В., Назаров В., Tournat V., Gusev V., Castagnede B. «Люксембург-горьковский эффект в гранулированной среде» Труды (восьмой) научной конференции по радиофизике, посвященной 80–летию со дня рождения Б.Н.Гершмана. 7 мая 2004 г., с. 209-211 (2004)

Tournat V., Gusev V.E., Zaitsev V.Yu., Nazarov V.E., Castagnede B., Bequin Ph., Inserra C. «Nonlinear acoustic effects in unconsolidated granular media» High intensity acoustic waves in modern technological and medical applications. Joint Workshop of Russian Acoustical Society (RAS) and French Acoustical Society (SFA). Special Session of the XVI Meeting of Russian Acoustical Society (Moscow. 14–18 November 2005), с. 86-92 (2005)

This paper deals with various manifestations of classical and non classical nonlinear acoustic effects that have been observed recently in unconsolidated assemblages of glass beads: operation of the parametric antenna with shear pump waves, non monotonous amplitude dynamics of the longitudinal second harmonic generated from a shear fundamental wave, cross-modulation of propagating waves. Theoretical interpretations of each of these non linear effects demonstrate the important role of the so-called weak contacts, i.e. contacts that support weaker static loads than the average one in the medium. In contrast, the linear wave propagation is mainly affected by the average and strong contacts. As a consequence, nonlinear acoustic methods are found to be much more sensitive than the linear methods for the evaluation of the granular materials in general, and may contribute to a better understanding of their peculiar properties.