The bubble tray is good for oxygen enrichment in the fish tank, with more bubbles and less noise. If bubble stones are used, they are generally two-headed. Can increase the oxygen in the bathtub. Disadvantages: it is not easy to clean, and sometimes it will affect the viewing.
There are three concepts about nanotechnology:
The first one is that in 1986, Dr. drexler, an American scientist, put forward molecular nanotechnology in his book The Machine of Creation. Because of this concept, the machine of combining molecules can be very practical, so that all kinds of molecules can be combined at will, and the structure of any kind of molecules can be made. The nanotechnology of this concept has not made significant progress.
the second concept, nanotechnology, has been positioned as the limit of micromachining technology. That is, the technology of artificially forming nano-sized structures through nano-precision "processing". This nano-scale processing skill also makes the miniaturization of the semiconductor reach its limit. Even if the existing technologies continue to develop, they will eventually reach the limit in theory, because if the line width of the circuit is gradually reduced, the insulating film that constitutes the circuit will become extremely thin, which will destroy the insulation effect. In addition, there are problems such as fever and shaking. Researchers are studying new nanotechnology to solve these problems.
The third concept is put forward from the biological point of view. Because organisms have nano-scale structures in cells and biofilms. The development of cellular biological computers and DNA molecular computers has become an important part of nanotechnology.