In a PM to me, the OP says that he wants to explode a virus (a medical one) by tuning a standing wave inside a plazma tube to the resonant frequency of the virus.
Why do people believe the lies that quack "doctors" talk about?
I understand your frustration with the subject, and although this forum isn't really the place to discuss the validity of so called 'pseudo-science' it bugs (see what I did there?) me too. However, regardless of the OP's intentions, providing its not hazardous and providing infomation isn't responsible for harm/crime, I don't see why we can't just provide answers.
Wehther you're producing a standing wave in liquid, or gas, either way its a fluid. Open ends of tubes reflect longitudinal waves as is often used in musical instruments, with air to resonate at a particular frequency. A typical setup would be a wide range frequency transducer (a 'speaker' for audio) at the end of a tube/cavity of a specific length. To create a standing wave, you must set the length of the tube, as well as the frequency of sound (above, below, or at audio frequencies) to resonate.
YouTube - Standing waves in water in a speaker cone
Standing Waves and Musical Instruments
A great link:
A New Wave: Scientists Write on Water | LiveScience
Simply providing a sound source (longitudinal waves) of a particular frequency doesn't create a standing wave, it all depends on the medium used, and the shape of the cavity the medium is in. In other words, in ain't easy. For 'zapping viruses', in a controlled situaiton I don't see why it wouldn't kill them, but the frequencies would be high, and it'll be impractical in any other situation. Plus, plenty of other things kill viruses, UV, RF, electricity