Sonication time effect

The overall pressure boost of a steam jet is obtained by multiplying the sonic boost effect times the velocity boost effect. The overall boost is called the jet s compression ratio. 

When PCP solution (Id4 M) under continuous air bubbling is subjected to ultrasound effects, the characteristic absorption bands decrease and the treatment leads to a complex mixture of products. Carbon-chlorine bonds are rapidly cleaved, and after a 150-min sonication time, 90% of the chlorine is recovered in the solution as chloride ions. PCP transformation in aerated solution occurs together with nitrite and nitrate formation. Carbon dioxide is a product of PCP degradation, and it has long been recognized as an inhibitor for sonochemical reactions. 

Figure 6.4 Effect of sonication time on API particle size in terms of >[4 gj ee cojor insert.)...

TABLE 6.10 Effect of Sonication Time on the Agglomerated API Particle Size After Exposure to Thermal Cycling"... 

The effect of ultrasonic treatment on com particles was examined by sonicating both cooked and raw corn slurry samples and the resulting particle size was compared with nonsonicated samples (controls). The peak of the particle size distribution curve shifted from 800 pm to around 80 pm following sonication at high-power levels for cooked corn slurry samples. In addition, the particle size reduction was directly related to the power level and sonication time. The particle size reduction at the... 

Landfester et al. [ 143] studied the miniemulsion polymerization of styrene using hexadecane as the costabilizer. When styrene miniemulsions were subjected to varying sonication times (see Table 5), very similar trends are seen as for the MMA miniemulsions. The particle size and the polydispersity of miniemulsion droplets rapidly polymerized after sonication either do not depend on the amount of the costabihzer, or are very weak functions of the amount of costabilizer (see Table 6). It was found that doubhng the amount of costabilizer does not decrease the radius nor have any effect on the polydis-... 

There are only two references to continuous US-assisted digestion, both by the same authors [11,12], who optimized the composition of the liquid phase, sonication time, temperature, volume of solvent and flow-rate. On the other hand, they failed to consider the potential effects of other important variables such as the shape of the container, the volume and nature of transmitting liquid, particle size and, especially, the position of the container in the ultrasonic bath. 

Figure 7.10. Effect of pulse length (A) and sonication time (B) on the US-assIsted determination of COD. Ampiitude 55%, tip depth 0.7 cm from the iiquid surface, (H2SO4) 56% (v/v), theoreticai oxygen demand 100 mglmi, temperature 27 2°C, sonication time in (A) 2 min, puise iength in (B) 0.9 s/s. (Reproduced with permission of Springer-Veriag, Ref [55].)...

Fig. 9 Effect of sonication time on emulsion droplet size for 0.4g/ml of poly(methyl methacrylate)/methylene chloride solution in 6% of polyvinyl alcohol (PVA) solution at a volume ratio of 15 2(ml/ml) sonicated at 20% (o), 50% ( ), and 100% ( ) of full power. (Adapted from Ref l)...

Figure 13. Effect of sonication time on measured mean particle size for samples formed in experiment L4.

A study on the cavitation effect of 28-kHz ultrasound on sonic intensity and sonication time was completed using the electrical method [89]. The experimental... 

Properties of nanoparticles and base fluid used in this study are shown in Table 1. De-ionized water was used as a base fluid. In the nanofluid, nanoparticles tend to cluster and form agglomerates which reduce the effective thermal conductivity. It is known that ultrasonication break the nanoclusters into smaller clusters. Hong et al. [41] investigated the role of sonication time on thermal conductivity of iron (Fe) nanofluids. The thermal conductivity of each nanofluid showed saturation after a gradual increase as the sonication time was increased. The thermal conductivity of 0.2 vol% Fe nanofluid exhibited 18% enhancement with a 30 min sonication and was saturated after 30 min. So, in order to obtain good quality nanofluids, it is essential that the solid-liquid mixture be exposed to ultrasonication. 

Figure 10. Effect of sonication time on P NMR signals of poly(dAdT) poly-(AAdT) 0 min, 31 C 10 min, 26°C 1 h, 28 C and 3 h, 20 C, each with 3 Hz line broadening. The average chair lengths determined by gel electrophoresis were 690, 195,116, and 84 bp, respectively (22).

Fig. 28 (a) Three polymers used in Striegel s work [230]. Effect of sonication time on the differential molar mass distribution of (b) PS-L 257, (c) PS-S3 85/255, and (d) PS-S8 25.5/202. (Adopted with permission from Striegel [230]. Copyright 2003 Elsevier)... 

FIGURE 1.90 Effective diameter as a function of the sonication time of the aqueous suspensions of nanosilicas (CsiO2=0.02, 0.25, 1.0, and 5.0 wt%) at the values from 70 to 350 m /g, DJS) is also shown for MCA suspension (5 wt%). (Adapted from Adv. Colloid Interface ScL, 91, Gun ko, V.M., Zarko, V.I., Leboda, R., and Chibowski, E., Aqueous suspensions of fumed oxides particle size distribution and zeta potential, 1-112, 2001e. Copyright 2001, with permission from Elsevier.)... 

The changes in the electrical conductivity of a liquid submitted to sonication have been observed by various authors. Experiments were essentially made on hydrocarbons, halocarbons,65 alcohols, and water, at frequencies between 250 and 1000 kHz. A typical curve of the conductivity (K) as a function of the sonication time is shown in Fig. 6(a). After sonication is started, K increases almost immediately. After switching off the power, the initial value is restored in a few minutes, which dismisses the hypothesis of the sonolytic decomposition of the medium to ionic species. This general aspect is found with all the liquids tested except ethanol (Fig. 6b), for which an initial decrease is found. Under chosen conditions of frequency and energy density, AK can be as high as 50%, and as usual with "sonochemical effects, it is increased by lowering the temperature. 

Our laboratory conducted a study to confirm that these same effects are seen when carbon nanotubes are sonicated in the presence of DNA. The results showed that length of the DNArSWCNT conjugates decreased with an increase of sonication time. We have also shown that carbon nanotubes made from different synthesis methods yielded different lengths on sonication. These results support the previous reports that sonication causes damage leading to shortening of the carbon nanotubes. 

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