Microwave heaters

So long as water is present m the adsorbent layer, the temperature does not nse above 100 °C However, microwave heaters will even perform pyrolyses when this has evaporated... 

Microwave heaters. Increasing interest is being shown towards applications in chemistry of microwave heating, both for solution and solid-state chemistry. Domestic ovens are so-called multi-mode instruments in which the microwaves are reflected by the walls of the cavity. This kind of equipment can irradiate several vessels in a cavity, whereas in a single-mode instrument there is one vessel at a fixed distance from the radiation source. 

Exploring Operation Limits—Dielectric and Microwave Heaters... 

These preliminary tests indicated an erratic response by the frozen book to the radiation. Equivalent drying did not occur with similar damaged materials. Whether the irregularities were caused by the material or the equipments performance was not evident. After the initial experiments with both dielectric and microwave heaters, the dielectric apparatus was chosen for additional experiments. This decision was based primarily upon this equipment s having the higher power capability. 

The forming line may also include the means for heating the mat ahead of the press. Microwave heaters have been used. Other systems apply steam or a steam/hot air mixture to heat the mat. Typically the mat can be heated to 50-60°C before the press. Temperatures in excess of this are likely to result in some resin cure ahead of the press. 

There are many ingenious sophisticated variations on the reactor cells, but a simple, though not very versatile, flow cell has been described for use in a microwave heater, where the reaction solution was percolated through sand in a test tube as the equivalent of multiple microchannels. This set-up was used to carry out a Bohlmann-Rahtz pyridine synthesis and a Fischer indolisation. ... 

The microwave region of the spectrum is situated between the radiofrequency (RE) and infrared regions and corresponds to wavelengths between 1 cm and 1 m. So as not to interfere with telecommunication and RADAR systems, domestic and industrial microwave heaters operate at either 12.2 cm (2.45 GHz) or 33.3 cm (900 MHz). ... 

An industrial microwave heating system consists of a dc power supply, a microwave generator (magnetrons are available in 915- and 2450-MHz bands and klystrons at the higher-frequency bands) and an applicator. A microwave heater has only one electrode. On the other hand, an RF device requires two electrodes. The power can only be drawn from an RF generator when there is material present in the applicator therefore, the material is an essential electrical component of the circuit and affects the electrical characteristics [59]. 

Electromagnetic sensors Microwave heaters Microwave near field sensors Microwave sensors... 

High resistivity, low-thermal conductivity, resistance to thermal shocks and low reactivity to metals Induction, dielectric and microwave heaters in contact with metals Si3N4, SiC, MgO... 

Dieiectric heaters Broadcasting equipment Microwave heaters... 

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