Direct sonication

Figure 3.5 (a) Indirect sonication using an ultrasonic bath, (b) Direct sonication using an ultrasonic horn, (c) Direct sonication... 

Dahlem O, Demaiffe V, Halloin V, Reisse J (1998) Direct sonication system suitable for medium scale sonochemical reactors. AIChE J 44 2724-2730... 

The reaction is performed in the bath itself and is therefore subjected to direct sonication. The acoustic field is more regular throughout the reacting system as a single flat emitting face is used. The vessel itself is enclosed and can be equipped with the... 

The polyaniline was prepared by emulsion polymerization following the procedure outlined in US patent 5,863,465 with DNNSAused as a dopant [22]. Carbon Nanotubes (CNI) manufactured the nanotubes used in the work either by a high-pressure fabrication method (Hipco SWNT) or via laser ablation (Laser SWNT). We found that excellent dispersions of the nanotubes in PANI could be produced by two different procedures. The nanotubes could either be directly sonicated into the PANI solution or first sonicated into xylene and that dispersion afterwards sonicated into the DNNSA-PANI solution. 

Fig. 5 Flow through reactor with direct sonication via an amplifying horn.

The first reactor type, which employs direct sonication, is represented by the lab scale system shown in Fig. 5. This flow reactor assembly consists of a titanium horn assembly, a piezoelectric transducer capable of variable energy output, and a flow through reaction chamber. This design provides for maximum... 

By directly immersing a vibrating metal plate or a horn into the reaction medium (direct sonication)... 

Large-scale batch sonochemical reactors can be designed on the basis of the performance of conventional laboratory sonicators if it is assumed that there are no serious scale-up factors. These are the cleaning bath reactors (indirect sonication) and reactors with immersible transducers or sonic probes (direct sonication). Continuous reactors use either wall-mounted transducers (indirect sonication) or sonic probes (direct sonication). 

M-Pact Glove — Designed with an anatomically engineered direct sonic welded rubber top, tapered finger stretch side panels, reflective ink Spandex... 

A second class of lipid derivatives that contained two hydrophobic chains and a NTA polar head group was synthesized the double lipidic chain contained 12 (DC-12), 14 (DC-14), 16 (DC-16), and 18 (DC-18) carbon atoms. Unlike the single-chained (sc) class of molecules, no supramolecular assembly was observed for the double-chained (dc) reagents upon direct sonication with CNTs. Moreover, unlike the SC class, these reagents were not water soluble and formed vesicles in aqueous solutions. To ascertain whether micelles were required for supramolecular assembly formation, MWNTs were sonicated in the presence of DC compounds and a 1% concentration of the surfactant SDS. A mixed micelle consisting of DC/SDS formed in the aqueous solution SDS was subsequently removed through dialysis. TEM (see Transmission Electron Microscopy (TEM), Techniques) showed the formation of half-cylinder striations that were approximately 5.5-7.5nm, which was in agreement with the size of the different lipidic chains the striations were >4.5 nm, which implied that they were not due to SDS. Therefore, the formation of micelles appears to be the key step for the formation of noncovalent supramolecular assemblies on CNTs. 

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