Bubble temperature

Fig. 1.6 The correlation between the bubble temperature at the collapse and the amount of the oxidants created inside a bubble per collapse in number of molecules. The calculated results for various ambient pressures and acoustic amplitudes are plotted. The temperature of liquid water is 20 °C. (a) For an air bubble of 5 pm in ambient radius at 140 kHz in ultrasonic frequency, (b) For an oxygen bubble of 0.5 pm in ambient radius at 1 MHz. Reprinted with permission from Yasui K, Tuziuti T, Iida Y, Mitome H (2003) Theoretical study of the ambient-pressure dependence of sonochemical reactions. J Chem Phys 119 346-356. Copyright 2003, American Institute of Physics...

Yasui K, Tuziuti T, Iida Y (2004) Optimum bubble temperature for the sonochemical production of oxidants. Ultrasonics 42 579-584... 

Yasui K, Tuziuti T, Kozuka T, Towata A, Iida Y (2007) Relationship between the bubble temperature and main oxidant created inside an air bubble under ultrasound. J Chem Phys 127 154502... 

Thermal conductivity of Ar(0.01772 W/mK) is higher than Xe (0.00565 W/mK) and hence the loss of heat from bubble containing Ar is more rapid as compared to Xe. So the bubble temperature with Xe is always higher than bubble with Ar gas, resulting in higher cavitational intensity. 

Rae J, Ashokkumar M, Eulaerts O, von Sonntag C, Reisse J, Grieser F (2005) Estimation of ultrasound induced cavitation bubble temperatures in aqueous solutions. Ultrason Sonochem 12 325-329... 

Based on these results, the reduction of Au(III) requires the formation of hot cavitation bubbles which cause pyrolysis of water and 1-propanol molecules. In addition, it is suggested that the number of hot cavitation bubbles and/or the bubble temperatures increase with increasing ultrasound intensity in the irradiation system. 

Tauber et al. [23] following the same method as Hart et al. but using tert-butanol as the methyl radical source, obtained a temperature of 3,600 K in 10 3 M /(77-butanol and reported, similar to Hart et al. that this temperature decreased with increasing /( / /-butanol concentration. More recently, this method was adopted by Rae et al. [24] and Ciawi et al. [25, 26] in aqueous solutions. Rae et al. examined the effect of concentration of a series of aliphatic alcohols, extrapolating a maximum temperature of about 4,600 K at zero alcohol concentration [24]. They also observed a decrease in temperature with increasing alcohol concentration, which correlated well with the alcohol surface-excess and SL measurements obtained in the same system. Ciawi et al. investigated the effects of ultrasound frequency, solution temperature and dissolved gas on bubble temperature [26],... 

SL thermometry) exhibiting a strong dependence on thermal conductivity, the more spatially and temporally averaged temperature (from the MRR method), which is more representative for sonochemical processes, does not show such dependence. It is probable that it is actually the water vapour content within the bubble not the gas itself that dictates the bubble temperature. 

Fig. 14.13 (a) Bubble temperatures estimated using the MRR method as a function of thermal conductivity for the rare gases, (b) Hydrogen peroxide concentration following sonication of pure water as a function of gas solubility in different rare gases ( ) He ( ) Ne (a) Ar ( ) Kr ( ) Xe ( ) He/Xe mixture [42] (reprinted with permission from the American Chemical Society)... 

Fig. 14.15 Cavitation bubble temperature at different alcohol concentrations at 363 kHz in (a) helium saturated and (b) argon saturated solutions, (c) Temperature at different alcohol concentrations in argon saturated solutions at 1,056 kHz [60]...

Assuming a cooler temperature for helium, this means the amount of heat energy available for pyrolysis is less, which would produce less hydrocarbon products. This ultimately would lead to a relatively smaller SL quenching compared to that observed in argon saturated solutions. The relative change in bubble temperature would also be less in helium saturated solutions due to the lower amount of hydrocarbon products generated. Solubility differences would re-enforce this. 

Ciawi E, Ashokkumar M, Grieser F (2006) Limitations of the methyl radical recombination method for acoustic cavitation bubble temperature measurements in aqueous solutions. J Phys Chem B 110 9779-9781... 

Okitsu K, Suzuki T, Takenaka N, Bandow FI, Nishimura R, Maeda Y (2006) Acoustic multibubble cavitation in water a new aspect of the effect of a rare gas atmosphere on bubble temperature and its relevance to sonochemistry. J Phys Chem B 110 20081-20084... 

The liquid range of a nonaqueous electrolyte system is defined at the upper limit by the temperature at which one of its components begins to vaporize (also called the bubble temperature, Ob) and at the lower limit by the temperature at which one of its components begins to crystallize (liquidus temperature, Apparently, along with restrictions im-... 

These subroutines are used to calculate respectively, the bubble temperature of a liquid composition, dew temperature of a vapor composition, equilibrium temperature and composition of the phases produced by the flash of a particular stream at known values of total vapor and liquid, and the composition and amount of the phases produced by the flash of a particular stream at a known temperature. All are done at the column pressure which applies. 

The following reactor performance in recycle is the aim over 99.9% per/pass propylene conversion over 88% cumene selectivity, adiabatic temperature rise below 70 °C, but a maximum catalyst temperature of 250 °C. The inlet pressure should be sufficiently high to ensure only one liquid phase. Thermodynamic calculations at 35 bar indicate bubble temperatures of 198 and 213 °C for propylene/ benzene ratios of 1/4 and 1/7, respectively (Figure 6.5). The reactive mixture can be maintained as liquid up to about 250 °C, since the concentration of propylene diminishes gradually by reaction. 

The effect of wind The effect of waves The effect of bubbles Temperature, humidity, and rain effects The effect of surfactants Summary of laboratory experiments... 

Figure 7. Vapor phase mole fractions of ethylene glycol (bottom-left), ethanol (top-left), water (top-right), and the bubble temperature (bottom-right) prediction from the NRTL-SAC model [20].

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