The conclusion of the theoretical part is that the relative

The conclusion of the theoretical part is that the relative theoretical data of the calculated implosion pressures were satisfactorily correlated with the relative intensities values Nocodazole of Ir,ave and Ir,max experimentally measured. Moreover the calculated curves suggest a possible operating zone between 50 and 60°C.
In the experimental part, US-assisted wool dyeing tests were carried out in the same plant used for mapping tests, in the same temperature range (40–70°C) and compared with the conventional wool dyeing test made at the “standard” temperature (98°C). The dyeing performances in presence and absence of US were verified by measuring ΔE (colour variation), Re,% (reflectance percentage), K/S (colour strength) and colour fastness.
From the data concerning the dyeing performances, it can be concluded that a temperature close to 60°C should be chosen as the recommended condition for US-assisted wool fabric dyeing. It must also be observed that the good result at 60°C is obtained also with a reduced dyeing time with respect to the reference test at 98°C. This leads to a reduction of the global energy consumption of the process.
Moreover the results obtained from mechanical tests on dyed samples demonstrate that the fabrics properties are better for the US-dyed sample, proving that the long dwell time at 98°C of the conventional dyeing negatively affects the wool fibres.

Introduction
A single bubble driven by a large sound field in a levitation cell undergoes nonlinear periodic radial oscillations, exhibiting at each Nocodazole a large expansion phase followed by a collapse. The high energy density at collapse time produces short visible light-pulse, termed single-bubble sonoluminescence (SBSL) [1–3]. When air is used as the dissolved gas, above a threshold in the driving amplitude, the energy focusing during the collapse produces temperatures high enough for air dissociation to take place, so that only argon and water vapor remain inside the bubble [4–10].
The bubble levitation cell is a now classical experimental setup used to observe this phenomenon. It is made of an acoustical resonator, spherical [11,12], cylindrical [1,13–15] or cubic [1,16,17], driven by piezoelectric ceramics in its breathing mode at a few tenth of kHz. The bubble is trapped at the pressure antinode in the cell center by the so-called primary Bjerknes force, which, for amplitudes moderate enough, counterbalances buoyancy and maintains the bubble stable against translational motion [18–21]. Observation of a stable spherical bubble also requires diffusional equilibrium, which is achieved by adequately degassing the water [1,6], down to 10–40% of the saturation concentration in the case of air [8,22,23]. The bubble must also be stable against shape instabilities, which is ensured in a given amplitude range [22,24,25].
Levitation cells owe their popularity to the fact that the radial dynamics of the trapped bubble closely follows the theoretical picture of a bubble driven by an isotropic sound field in an infinite liquid domain [22,26,27]. The latter can be reasonably modeled by a small set of ordinary differential equations, allowing an efficient scan of the parameter set [28–31]. This theory has been successfully used to explore the details of the light-emission mechanism [32].
On the other hand, a bubble oscillating in the stable SBSL regime is known to show a clear acoustic emission. The latter can be recorded by an hydrophone or a focused transducer located near the bubble [21,33]. An easier and non-invasive method consists in recording the output signal of a small piezo-ceramics glued on the side of the levitation cell [1,33]. Holzfuss and co-workers showed that an SBSL bubble had a perfectly periodic acoustic signature, constituted of a rich set of harmonics of the driving frequency [21]. It can be conjectured that this signature would be modified when a perturbing object approaches or appears sufficiently close to the bubble. Thus, real-time acoustic monitoring of the levitation experiment may allow to detect otherwise non-predictable events such as a cell or droplet passing near the bubble, or the growth of a crystal in its neighborhood. Using this information may for example allow to trigger a camera and image the event as soon as possible.