Q-Sense Quartz Crystal Microbalance with Dissipation (QCM-D) technology animation

[aprilpieces]

always find the dissipation data is confusing

[MsQSense]

@aprilpieces Let us try to explain it better:

The dissipation (D) is the sum of all energy losses in the system per oscillation cycle.

Think of a bell. If I hit the bell it will start to oscillate and make a sound for quite some time. This is the case of a rigid layer oscillating on the sensor. In the other case I hit the bell and put my hand on it. The bell will stop ringing quite quickly due to my (soft) hand dampening the motion.

[aprilpieces]

@MsQSense THX, I do like the bell metaphor.

[MsQSense]

@aprilpieces

...This is the case of the sensor with a soft film on it. It will dampen quickly, which gives a high dissipation.

The resonance frequency (f) of the crystal depends on the total oscillating mass, including water coupled to the oscillation. When a film is attached to the sensor crystal, the frequency decreases. If the film is thin and rigid the decrease in frequency is directly proportional to the mass of the film (the Sauerbrey relation)...

[MsQSense]

@aprilpieces

...But when the film is soft, there is energy lost in the system which is only detected by the dissipation. This means that in order to quantify the mass of a soft film, one needs the information from both f and D. With only f, the mass of a soft film would be underestimated. The other good part with having both f and D and measuring them at several overtones is that it enables the quantification of viscosity and elasticity of the film.

[drminatti]

There is a huge error in this animation: we can NEVER touch the golden electrode with the tweezers!



[azzaelhm]

What's the sensibility of the device? (In grams)

[aprilpieces]

@azzaelhm nanogram

[Lau25052]

Awesome!

[saintsaevio]

WHAT THE FUCK IS THIS