Re: secondary x-rays from ultra-sound:proved to exist

[Rachid Zitouni <azittouni@yahoo.com>]

--- LAM HOI CHING <lamhc@hkusua.hku.hk> wrote:

> Ultansonic wave is only a kind of mechanical
> effect,it is a kind of
> macroscopic phenomenon in the material, it affects
> only the mechanical
> vibration of atom, but  not to the atomic structure
> change like the atomic
> orbital,whereas x-rays are due to internal
> transition of atom or molecules,
> in fact from electrons of the atom, these two
> effects are not in the same
> category.
> 	But you can discuss ionizing damage from x-ray
> (doses)
> or you can still discuss the harmful effect of
> ultrasound. The two types of
> interactions (by ultra-sound and x-ray) are totally
> different.
> 
> 

Few years ago, I would have agreed with you. Yes, ultrasound acts on
the bulk of the matter, at the macroscopic level and X-rays at the
electronic level.
Ultrasonic waves are not supposed to ionize matter.

BUT:
Very low Enegy X-rays have been detected following diagnostic
ultrasound. I lost track of the paper which was published on this
subject.This phenomenon has been proved to exist. I haven't done the
experiment myself, but I suppose the excitation of matter by ultrasound
at the molecular level may, under certain circumstances (which are to
be determined), give rise to very low energy X-ray 

By the way, I haven't referred to any biological effect related to
these low-energy X-rays. In fact, the dose in this case is meaningless.

Thanks for the reply and keep digging if the subject is of interest to
you.

Abderrachid ZITOUNI, health Physicist

azittouni@yahoo.com
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