MNDO study of the tautomers of nucleic bases: Part III. Reinvestigation of the amino-type tautomers structure
Abstract MNDO recalculations with full geometry optimization for the amino-type tautomers of cytosine, adenine and guanine predict noncoplanarity of the amino nitrogen atom with heteroaromatic rings. These molecular structures are about 2.1 kJ mol −1 more stable in comparison with “coplanar” structures. Bond lengths, valence angles, dipole moments and ionization potentials of the “coplanar” and “noncopolanar” forms do not differ significantly.
This paper presents design and characteristics of a compact, highly integrated Ka-band T/R module built by using a miniature magnetron in the transmitter chain. By implementing a solid-state modulator and microstrip design in the microwave part of the receiver, the overall size of the module has been reduced significantly. The module provides capabilities to realize Doppler date processing by using a digital coherent-on-receiver technique.