Microwave frequency range, absorption cross

The significance of the above theoretical estimates of the absorption cross section lies in comparing the absorption of the incoming radiation by the biopolymer with that of the surrounding medium (water). The absorption cross section for water in the microwave frequency range can be obtained from the dielectric dispersion data (5) by using the following expression... 

Both microwave and millimetre wave radiation can be channelled in any direction by a waveguide made from metal tubing of rectangular cross-section, the dimensions depending on the frequency range. The absorption cell is also made from waveguide tubing. 

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