School children know that substance has 3 main aggregate States – solid, liquid and gaseous. But few people remember that there are others. For example, the state of the plasma. To it is not so easy, however, a group of physicists-lovers turned the conventional microwave oven available in the plasma generator.
As is known, the principle of operation of the microwave oven based on the effects of electromagnetic fields on molecules. Under normal conditions, the density of the molecules in a substance is very large, which leads to oscillations, causing objects placed in a magnetic field, heat. In this case the particles can not gain the necessary amount of energy to “accelerate” and move in a plasma state. However, if not solid, and the gas in the desired concentration, the distance between molecules will be greater, which increases the chances of getting a plasma.
This is what scientists and used in their work. They took a sealed vessel with oxygen, the content of which was precisely calculated. In addition, it was calculated and the optimal pressure inside the vessel, and that fluctuations in the gas do not break it. When placing the vessel in a microwave oven, for gas transport in the plasma takes a few minutes, and the vessel begins to glow. According to physics, the resulting plasma can be used to examine and modify the properties of various substances. As an example, they demonstrated hydrophilic (i.e., absorb moisture) polymer is a polydimethylsiloxane. After a few seconds of “bathing” in the plasma, a property of the polymer has changed to the opposite – it has become hydrophobic (i.e. water repellent). In addition, the authors believe that with the “microwave plasma” you can change the conductivity and other properties of various substances.
Physics turned a microwave into the plasma generator
Vladimir Kuznetsov