Interaction, between ultrasound and

There is a good understanding of the interaction between ultrasound and matter for many materials, and mathematical theories are available to relate the measurable ultrasonic parameters to the composition and microstruture of these systems. The most important examples of these types of system in the food industry are homogeneous liquids, emulsions and suspensions. 

Interaction between ultrasound and tissue can be characterized by a number of parameters like speed of propagation, attenuation, absorption coefficients etc. As ultrasound velocity is characteristic for a particular tissue the possibility is opened for ultrasound velocity tomography. The principles hereof and implications for medicine have been described by Greenleaf et al. (1975). In ultrasound velocity tomography transmitters and receivers are positioned around the object under study. Times of flight of ultrasonic pulses from transmitter to receiver are measured accurately. By rotating the transmitters and receivers in a plane around... 

While soundwaves are commonly used for communication through various media, some unique events occur in liquids when soundwaves interact with the medium. In particular, when ultrasound passes through a liquid medium, it strongly interacts with small gas bubbles that exist in the liquid. Such interaction between ultrasound and gas bubbles leads to a phenomenon known as acoustic cavitation [31, 32]. 

Drinkwater, B.W., Dwyer-Joyce, R.S. and Cawley, P., 1996, A study of the interaction between ultrasound and a partially contacting solid-solid interface, Proc. R. 

Servant G, Laborde JL, Hita A, Caltagirone JP, Gerard A (2003) On the interaction between ultrasound waves and bubble clouds in mono and dual-frequency sonoreactors. Ultrason Sonochem 10 347-355... 

Table 22.1. The ultrasound meal accommodation test (UMAX) was developed at Haukeland University Hospital on the basis of close interaction between scientific and clinical work in patients with dyspepsia. Before entering the protocol, the patients have been carefully studied with history, physical examination, blood tests, testing for H. pylori and upper endoscopy. In some cases, additional examinations are performed to rule out organic causes of their symptoms. The protocol presented here is the mainstream clinical protocol. In scientific studies, other elements are often added. A 500-ml liquid meal of commercial meat soup (Toro clear meat soup, Rieber Son A/S, Bergen, Norway) containing 1.8 g protein, 0.9 g bovine fat, and 1.1 g carbohydrate (20kcal) is ingested over a period of 4 min. The soup is preheated and then cooled to 37°C to improve imaging quality by reducing the amount of air bubbles. Psychometric evaluation is also performed...

In Ultrasound computed tomography, the interaction between ultrasound wave and the body is used to determine the distribution of sound velocity c and the tissue density p. Ultrasound signals are stimulated and received by piezoelectric transducers. Received data is also processed by above mentioned algorithms, i.e by applying Fourier transform algorithm in order to reconstruct internal stmctures of the body as indicated in the following diagram ... 

Ultrasound is used to obtain information about the properties of a material by measuring the interaction between a high frequency sound wave and the material through which it propagates. This interaction depends on the frequency and nature of the ultrasonic wave, as well as the composition and microstructure of the material. The parameters most commonly measured in an ultrasonic experiment are the velocity at which the wave travels and the extent by which it is attenuated. To understand how these parameters are related to the properties of foods it is useful to consider the propagation of ultrasonic waves in materials in general. 

In non-ideal mixtures, or systems where scattering of ultrasound is significant, the above equations are no longer applicable. In these systems the ultrasonic properties depend on the microstructure of the system, and the interactions between the various components, as well as the concentration. Mathematical descriptions of ultrasonic propagation in emulsions and suspensions have been derived which take into account the scattering of ultrasound by particles [20-21]. These theories relate the velocity and attenuation to the size (r), shape (x) and concentration (0) of the particles, as well as the ultrasonic frequency (co) and thermophysical properties of the component phases (TP). 

Interaction between Metallic Copper and [(CH3)2NCS2—]2 (TMTD) with Simultaneous Application of Ultrasound [715]... 

In many applications it is difficult to apply surface vibration because of the large mass of the heat transfer apparatus. The alternative technique is then utilized, whereby vibrations are applied to the fluid and focused toward the heated surface. The generators that have been employed range from the flow interrupter to the piezoelectric transducer, thus covering the range of pulsations from 1 Hz to ultrasound of 106 Hz. The description of the interaction between fluid vibrations and heat transfer is even more complex than it is in the case of surface vibration. In particular, the vibrational variables are more difficult to define because of the remote placement of the generator. Under certain conditions, the flow fields may be similar for both fluid and surface vibration, and analytical results can be applied to both types of data. 

As it is seen, when nanocomposite is introduced and undergoes ultrasound dispergation, the band intensity in the spectrum increases significantly. Also the shift of the bands in the regions 1100 - 1,300 cm , 2,100 -2,200 cm is observed, which can indicate the interaction between sodium lignosulfonate and nanocomposite. However after 2 weeks the decrease in band intensity is seen. As the suspension stability evaluated by the optic density is 30 days, the nanocomposite activity is quite high in the period when IR spectra are taken. It can be expected that the effect of foam concrete modification with such suspension will be revealed if only 0.001% of nanocomposite is introduced. 

In an insonated system, it is possible to optimize the ultrasound power and deposition potential in order to target a specific heavy metal. Fig. 3(a,b) shows the variation in ultrasound power and deposition potential for copper and lead from a dilute mucous solution. It is evident that the optimum deposition of copper is effected at 200 W cm ultrasound power and potential of —1.6 V. For lead, this is found to be 100 W cm ultrasound power and a potential of —1.7 V. We conclude that stability of the deposit on the surface of the electrode is dependent on the interaction between the deposit and the electrode surface and the cavitational activity, which also acts to depassivate the electrode in the presence of glycoproteins from the mucus. 

Aveline C, Cognet F, Bonnet F. Ineffectiveness of intralipid infusion for central nervous toxicity following ultrasound-guided sciatic nerve block with lidocaine-ropivacaine solution interaction between carbamazepine, local anaesthetic and intralipid Eur J Anaesthesiol 2010 27 1070-2. 

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