Qsonica SONICATOR S-4000, Руководство по эксплуатации

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processing. Three different sizes are available.
Most laboratory grade plastic or borosilicate glass vessels that will fit into the cup are suitable
for sonication. Polystyrene and polycarbonate are the best transmitters of acoustic energy.
Polypropylene and polyethylene are softer and may be less effective. Glassware must be
free of any scratches and fully annealed or it may over stress and crack.
Ultrasonic energy is radiated directly upward through the vessel while transmission through
the side is negligible. For this reason, flat-bottomed vessels are best and round bottomed
are next best. Vessels should have thin, uniform bases, without any heavy edges or centers.
Conical tubes should be tilted to expose maximum sample area to the horn. Samples should
be wide and shallow, rather than tall and narrow. Maintain a small clearance around the
vessel to allow adequate coolant flow.
Energy transmission to the sample vessel can be determined easily by the pattern of
sonication (cavitation bubbles or micro streaming) in the coolant. At low levels, the bubbles
will usually appear as a dome of bubbles capping the coolant exit in the face of the horn. As
the amplitude of the ultrasonic vibration (amplitude control knob setting) is increased, the
bubble pattern will lift and become vertical diaphanous streams in the center of the cup,
sometimes forming a spider-like pattern.
Output (Amplitude) Settings
When working with small samples there is a tendency to turn the Amplitude setting too high.
Doing so may cause the ultrasonic energy to go around the vessel, not through it.
It is important to run the unit and look at the sonication field before you use the unit on actual
samples. Notice the tiny bubbles traveling through the liquid. The action above the Horn
may resemble a mini tornado. As you increase the amplitude setting you will see that the
intensity of the sonication increases and actually moves higher through the liquid.
Sample height above the horn should loosely correspond to the amplitude setting. The
closer the samples are to the horn, the lower the setting should be used.
At high settings it is possible to generate so many cavitation bubbles that the Horn creates
an air pocket where energy will not be effectively transferred. Too much amplitude will
reduce the effectiveness of the sonication inside your vessel by expending too much energy
in generating cavitation outside the vessel. Lower amplitude settings are recommended for
the Cup Horn.
Cup Horn Maintenance
The cup is made of acrylic plastic and should be cleaned periodically with a mild detergent
like soap and water. Do not clean with solvents or abrasives. The horn is a tuned resonant
body of titanium alloy. Do not attempt to resurface the horn if it shows erosion after extended
use.