hi mattstat I don't know this instrument however as I already said the transducer will be 60 cm from the ground, so it will have to pass through 60 cm of air, then 4 cm of soil/soil to then get to the root, can the sonicator do this?
I don't understand the requirement for the transducer to be 60 cm from the ground or exactly what that means to you.
In sonicators, the transducer is near the top (where the wire goes in in the image below). The sound is coupled through the metal bar (horn), and exits at the tip (in the blue liquid in the image below). If for some reason you need a longer horn, that can probably be incorporated. Ultrasonic plastic welders employ similar geometry/coupling mechanisms and might be another source for a longer device.
I'm not saying this is the best option, it's just one from a name-brand supplier. There are cheaper options available from other manufacturers and sites. Different power levels are also available.
https://www.fishersci.com/shop/prod...-120-sonic-dismembrator-4/p-3974654#?keyword=
In sonicators, the transducer is near the top (where the wire goes in in the image below). The sound is coupled through the metal bar (horn), and exits at the tip (in the blue liquid in the image below). If for some reason you need a longer horn, that can probably be incorporated. Ultrasonic plastic welders employ similar geometry/coupling mechanisms and might be another source for a longer device.
I'm not saying this is the best option, it's just one from a name-brand supplier. There are cheaper options available from other manufacturers and sites. Different power levels are also available.
https://www.fishersci.com/shop/prod...-120-sonic-dismembrator-4/p-3974654#?keyword=
Note that the gel is a medium to illuminate any air in the path between the transducer and the flesh. If the ultrasound in airborne for even 1cm, no amount of gel will transform the radically different acoustic impedances. Water is used to expose things to ultrasound, ie submerge the transducer and target in water.
Rabbilo certainly hasn't explained that to my satisfaction.
There would have to be a transducer-soil interface.
According to a quick search, the propagation of ultrasound in soil depends on soil compactness, soil porosity, water content, particle size, and particle size distribution.
What a fun bunch of variables, each just crying out to be investigated in turn!
no guys, I've already explained it, the transducer must be 60 or 50 cm above the ground because any closer could negatively interfere with the growth of the plant. and then there are the herbs that could damage it. therefore the ultrasounds must travel 60 or 50 cm in the air and then a few cm in the ground
Hi Galu, there is no soil and transducer interface but the distance of 60 cm between the transducer and the ground, but I have explained this many times. and since there is air first and then the ground then there is acoustic impedance that I want to eliminate or reduce
I found the following article on the reduction of pesticide residues in plants through the use of ultrasound.
It MAY help shine a light on Rabbilo's line of research:
https://www.sciencedirect.com/science/article/abs/pii/S0308814617313584
Mention is made if an ultrasonic probe operating at 24 kHz.
The ultrasound is responsible for the breakdown of contaminant molecules present inside cavitation bubbles.
I'm not sure what that sentence means.
I don't follow - how could you eliminate or reduce the acoustic impedance of the soil?
It MAY help shine a light on Rabbilo's line of research:
https://www.sciencedirect.com/science/article/abs/pii/S0308814617313584
Mention is made if an ultrasonic probe operating at 24 kHz.
The ultrasound is responsible for the breakdown of contaminant molecules present inside cavitation bubbles.
I'm not sure what that sentence means.
I don't follow - how could you eliminate or reduce the acoustic impedance of the soil?
Yes Galu, I had already read that article and it is very similar to this technology. then by herbs I mean that herbs grow around the plant naturally and by positioning the transducer too close to the plant these herbs could climb up and destroying it is very simple. as regards the last sentence, I'm talking about impedance precisely because first there is the 60 cm layer of air and then there is the 3 or 4 cm layer of soil to penetrate, this is why I talk about impedance and this is the problem I want to overcome but what name are we managing
A very small percentage of the ultrasonic energy will be transmitted into the soil if the transducer is in the air.
The ultrasound would have to be directed towards the soil via a medium whose acoustic impedance is close to that of moist soil - perhaps through a tube full of water (z = 1.5 MRayl) closed at the bottom end with polyethylene (z = 1.8 Mrayl) - NOT glass which has too high an acoustic impedance (z = 11.6 MRayl).
This procedure is known as acoustic impedance matching.
The ultrasound would have to be directed towards the soil via a medium whose acoustic impedance is close to that of moist soil - perhaps through a tube full of water (z = 1.5 MRayl) closed at the bottom end with polyethylene (z = 1.8 Mrayl) - NOT glass which has too high an acoustic impedance (z = 11.6 MRayl).
This procedure is known as acoustic impedance matching.
yes galu I also thought of a similar solution, but I can't put anything between the transducer and the ground because the plants must be free. However, is there another way perhaps similar to this to reduce the impedance?
You mean, is there a similar way to match the impedances. Not that I can think of at present.
Is the ultrasound transducer you are currently using omnidirectional?
I assumed it to have a focused beam which would obviously concentrate the energy on the air-soil interface.
P.S. May I ask if your specialism is in biology or perhaps in both biology and physics?
Galu my greatest expertise is in biology, however I would like to tell you that the transducers have a frequency of 20 khz therefore very broad even if ultrasound, perhaps with a reflector that directs the entire beam onto the ground I could solve the problem. I also heard that by coupling the phase you can overcome the impedance problem
I'm not trying to be rude - just offering advice for future requests.
When you ask for creative solutions from others, it helps to give enough information so someone can provide a useful suggestion. Or at least prevent people from spending their time making suggestions that aren't viable.
In your mind, where all the variables and limitations are known, the situation may be simple. It seems some of us were left confused as to what the restrictions were there for and what they actually meant. Simply saying it "must be 60 or 50 cm above the ground" doesn't tell us whether that's because you're trying to replicate a previous test, that's where a test system gantry is so things need to mount there, that's where some standard piece of farm equipment runs and you want to emulate that, if getting closer would block light, whether you're afraid the ultrasound damages the above-ground foliage, whether you are continuously exposing things to ultrasound, whether a short dose with a penetrating probe from above or the side is a viable solution, etc., etc., etc.
When you ask for creative solutions from others, it helps to give enough information so someone can provide a useful suggestion. Or at least prevent people from spending their time making suggestions that aren't viable.
no no I'm not angry maybe the translation can transform the meaning 😥. However, I thought that if the transducer beam was conveyed with a parabolic reflector, the beam could be narrowed and a flat PNDA created, what do you think? or on Wikipedia I read when the frequency of the wave and the sound pressure are in phase with the transmission, also in this second case what do you think?
Galu no no I meant to say flat "wave", which is created after being conveyed by the parabolic reflector
Galu yes it's a flat wave, then do you think the idea is feasible? And what do you think about phase coupling?
