Sonication/sonochemical synthesis

Arefian NA, Shokuhfar A, Vaezi MR, Kandjani AE, Tabriz MF (2008) Sonochemical synthesis of SnO/ZnO nano-Composite the effects of temperature and sonication power. In Ochsner A, Murch GE (eds) Defect and diffusion forum, vol 273-276, Diffusion in solids and liquids III., pp 34-39... 

In the case of dichlorosilanes, oligomerization to form cyclopolysilanes occurs in high yields, with the product s ring size dependent upon the steric bulk of the starting silane (219). Boudjouk initially reported (221) the synthesis of West s novel disilene (222) upon sonication of lithium with the highly hindered bis(mesityl)dichlorosilane [Eq. (44)]. It is difficult, however, to obtain consistent results with this sonochemical synthesis of the... 

Results of a chemical activation induced by ultrasound have been reported by Nakamura et al. in the initiation of radical chain reactions with tin radicals [59]. When an aerated solution of R3SnH and an olefin is sonicated at low temperatures (0 to 10 °C), hydroxystannation of the double bond occurs and not the conventional hydrostannation achieved under silent conditions (Scheme 3.10). This point evidences the differences between radical sonochemistry and the classical free radical chemistry. The result was interpreted on the basis of the generation of tin and peroxy radicals in the region of hot cavities, which then undergo synthetic reactions in the bulk liquid phase. These findings also enable the sonochemical synthesis of alkyl hydroperoxides by aerobic reductive oxygenation of alkyl halides [60], and the aerobic catalytic conversion of alkyl halides into alcohols by trialkyltin halides [61]. 

An interesting sonochemical synthesis of elongated copper nanoparticles (approx. 50 X 500 nm) has been described [164]. The principle of the method is the use of an organised medium of aqueous cetyltrimethylammonium p-toluenesulphonate as the supporting fluid for sonication. The resulting nanoparticles are produced from the sonication of copper hydrazine carboxylate in the interconnected threadlike micelles which act as a template. The nanoparticles are coated with a layer of the surfactant. In the absence of the detergent the particles were spherical (ca. 50 nm). 

Sonochemical Synthesis of M50 Type Steel Nanopowders. A dispersion of 15g (0.0765 mol) of Fe(CO)5, 0.66g of Cr(EtxC6H6-x)2, 0.75g (0.0015 mol) of CpMo(CO)3 and 1.0 g of polyoxyethylene sorbitan trioleate (surfactant) in dry decalin was sonicated at 50% amplitude for 7h at room temperature in a sonochemical reactor fitted with a condenser and gas inlet and outlet tubes connected to a mercury bubbler. The color of the solution turned dark and then black within a few minutes and this reaction mixture was sonicated until the formation of shiny metallic particles was observed on the walls of the reaction vessel. The sonication was then stopped and the decalin solvent was removed from the reaction flask via vacuum distillation. Fine black powder (Yield 4.448g) remained at the bottom of the reactor, which was then isolated, transferred to a vial and coated with mineral oil before the compaction. 

P. Jabbarnezhad, M. Haghighi, P. Taghavinezhad, Sonochemical synthesis of NiMo/Al203-Zr02 nanocatalyst Effect of sonication and zirconia loading on catalytic properties and performance in hydrodesulfurization reaction. Fuel Process. Technol. 126, 392-401 (2014)... 

A. Ziarati, J. Safaei-Ghomi, S. Rohani, Sonochemically synthesis of pyrazolones using reusable catalyst Cul nanoparticles that was prepared by sonication, Ultrason. Sonochem. 20 (2013) 1069-1075. 

Abstract This chapter discusses the effect of ultrasound propagation in water and aqueous solutions, in the atmosphere of inert and reactive gases. Sonochemical studies of aqueous solutions of divalent and trivalent metal ions and their salts have been reviewed and the precipitation behaviour of hydroxides of metal ions has been discussed. Synthesis of nanoparticles of many metals using ultrasound and in aqueous solutions has also been discussed briefly. Besides, the nephelometric and conductometric studies of sonicated solutions of these metal ions have been reported. 

In many syntheses activation is not effected by sonochemical preparation of the metal alone but rather by sonication of a mixture of the metal and an organic reagent(s). The first example was published many years ago by Renaud, who reported the beneficial role of sonication in the preparation of organo-lithium, magnesium, and mercury compounds [86]. For many years, these important findings were not followed up but nowadays this approach is very common in sonochemistry. In another early example an ultrasonic probe (25 kHz) was used to accelerate the preparation of radical anions [87]. Unusually for this synthesis of benzoquinoline sodium species (5) the metal was used in the form of a cube attached to the horn and preparation times in diethyl ether were reduced from 48 h (reflux using sodium wire) to 45 min using ultrasound. 

An intramolecular 2-alkylation was also observed in a sulfonyl free radical induced addition-cyclization <95SL763>. A key intermediate in a new synthesis of pallescensin A (a biologically active labdane diterpene) was prepared by a cationic cyclization reaction with a furan <95SYN1141>. The sonochemical Barbier reaction was extended to carboxylate salts. 2-Furanylketones 10 can be obtained by sonication of a mixture of furan, lithium carboxylate, an alkylchloride, and lithium in THF <95JOC8>. 

In addition to the above reported synthesis of ferrites our search has revealed that aluminates [119], nickelates [120], and manganates [121], have also been prepared by the sonochemical method. Nanosized nickel aluminate spinel particles have been synthesized [119] with the aid of ultrasound radiation by a precursor approach. Sonicating an aqueous solution of nickel nitrate, aluminum nitrate, and urea yields a precursor which, on heating at 950 °C for 14 h yields nanosized N1A1204 particles with a size of ca. 13 nm and with a surface area of about 108 m g-i. 

The syndiesis of nanomaterials is being pursued via a number of methods. Physical mediods include sonication and ball milling of solids ((f). Chemical techniques include vqwr condensation methods (7-P), micellular synthesis, chemical reduction (//), sonochemical syndiesis (/O), and the sol-gel methodology (12-20). For nanomaterials to have a notewordiy impact in the area of energetic materials processes for dieir syndiesis must satisfy significant production specifications such as cost, health and safety, and reproducibility. The sol-gel mediod provides another iqqnoach to nanomaterials syndiesis for energetic nanoconqiosites and, in some reflects, it is a more suitable candidate method than those Ascribed previously. 

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