Sonic methods

Applications The physical principle of measurement is similar to the scanning acoustic microscopy discussed in the Section 14.23, but applications and the method of data processing are essentially different. Sonic methods were used in the following applications to filled materials the effect of particle size and surface treatment on acoustic emission of filled epoxy, longitudinal velocity measurement of tungsten filled epoxy, and in-line ultrasonic measurement of fillers during extrusion. Numerous parameters related to fillers can be characterized by this non-destructive method. 

Applications. Determination of specific surface area of filler which is used as a factor relative to particle size, porosity, and surface activity of filler. 

Testing procedure. The automated instruments (e.g., Quantachrome NOVA 1000 or Micrometries Gemini 2360) are used for rapid surface determination. The physical adsorption of nitrogen or other inert gas should be conducted at a pressure which is within the range of linearity. 

Standard methods. ASTM C 1069, ASTM D 1993, ASTM D 5604, BS 4359 Part 1,1SO 9277 

Tap test. In this method, a coin is used as a special tapping hammer. Tone differences indicate inconsistencies in the bonded joint. Sharp, clear tones 

uneven glue Clamping pressure too low Increase pressure, check that 

Adhesive residue has Excess air stirred into Vacuum-degas adhesive before 

Voids in bond (i.e., Joint surfaces not properly Check treating procedure  

Adhesive can be Adhesive not properly cured Use higher curing temperature 

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Sonic Methods A fixed-point level detector based on sonic-propagation characteristics is available for detection of a liquid-vapor interface. This device uses a piezoelectric transmitter and receiver, separated by a short gap. When the gap is filled with liquid, ultrasonic energy is transmitted across the gap, and the receiver actuates a relay. With a vapor filling the gap, the transmission of ultrasonic energy is insufficient to actuate the receiver. 

It is quite clear that in the near future extraction of non-ionic surfactants from solid matrices will be based on SFE, PLE and sonication methods. The initial costs for SFE/PLE equipment will be earned back quickly by the reduction of man-hours and solvent consumption per sample. For sonication methods, not even this financial barrier is present. More emphasis must be laid on quality assurance of the extraction, clean-up and detection methodologies. The recently available 13C-labeled standards will help to account for matrix... 

The main comparisons between extraction methods have been made between the Soxhlet, ultrasonication, and supercritical fluid extraction [377, 398,456,461,462]. This has primarily been prompted by the need to evaluate critically the relative merits of SFE as an alternative to the more established methods. Richards and Campbell [456] made a comparison between SFE, Soxhlet, and sonication methods for the determination of some priority pollutants in soil. The SFE apparatus was the same, relatively standard system as described by Campbell et al. [457] with the addition of a C02 cryogenic trap to... 

The comparability of results has prompted the use of the Grindo-Sonic method in hardness tests of other ceramic materials and has led to attempts... 

Non-Destructive Sonic Method for Hardness Measurement of Brittle Materials... 

Jakubicki W., Janusz Cz., Szymanski A., 1979, Hardness measuring of glass and ceramic bodies using non-destructive sonic method, VIIIBAUSIL, Weimar, Vertrag Nr 4.1.5. 

An extraction procedure performed by sonication method for dried marine sediments and soil followed by the analysis of the extracts using an electrochemical immunosensor based on magnetic beads and carbon screen-printed electrodes is described in the protocol (see Procedure 25 in CD accompanying this book). 

Marvin et al. [14] compared sonication with Soxhlet for the extraction of PAHs from sediments, and from an urban dust standard reference material (SRM 1649). The sonication method required less than 5 g of sample. The amount of organic materials extracted by sonication with two solvents was 2.53 + 0.10% of the sediment samples (w/w), while 2.41 + 0.14% was extracted by Soxhlet. Sequential sonicaion with two solvents was much faster (45 minutes) than Soxhlet (2 days), with practically the same extraction efficiency. The variation of PAH extracted by sonication from the urban dust SRM was within 15%. 

The sonication method of magnesium activation has been employed to initiate sluggish Grignard reactions in ether. Sonication is the preferred technique for effecting the Barbier variation, in which the electrophilic species and organohalide are introduced concomitantly, and the Grignard reagent is then intercepted as fast as it is formed (Fig. 15) [36]. 

In general, elastic liposomes are prepared using similar methods to conventional liposomes, most commonly using the conventional rotary evaporation sonication method (26, 28-30). A typical preparation method is outlined ... 

Chlorinated phenolic compounds in air-dried sediments collected downstream of chlorine-bleaching mills were treated with acetic anhydride in the presence of triethylamine. The acetylated derivatives were removed from the matrix by supercritical fluid extraction (SEE) using carbon dioxide. The best overall recovery for the phenolics was obtained at 110°C and 37 MPa pressure. Two SEE steps had to be carried out on the same sample for quantitative recovery of the phenolics in weathered sediments. The SEE unit was coupled downstream with a GC for end analysis . Off-line SEE followed by capillary GC was applied in the determination of phenol in polymeric matrices . The sonication method recommended by EPA for extraction of pollutants from soil is inferior to both MAP and SEE techniques in the case of phenol, o-cresol, m-cresol and p-cresol spiked on soil containing various proportions of activated charcoal. MAP afforded the highest recoveries (>80%), except for o-cresol in a soil containing more than 5% of activated carbon. The SEE method was inefficient for the four phenols tested however, in situ derivatization of the analytes significantly improved the performance . 

Fig. 19. Plot of birefringence as measured by the compensator technique against the orientation function as measured by the sonic method. Values in parenthesis represent theoretical values for Nylon 66, cellulose, and polypropylene from top to bottom respectively...

Samuels, R. J. Morphology of deformed polypropylene. Quantitative relations by combined X-ray, optical and sonic methods. J. Polymer Sci. A, 3, 1741 (1965). 

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