The measurement and verification of parameters of pulse electromagnetic radiation generated by a large-radius ring current

Experimental and analytic studies of the generation and propagation of electromagnetic radiation due to repetitive current pulses of a nanosecond duration (peak power to 1 MW, current slew rate of 3.5 A/ns) are presented. The radiation source was a fine-wire ring antenna of large radius (ρ_a=1.4 m). The antenna was driven along its full length instantaneously within the time τ shorter than the time of wave travel along the ring diameter (τ≤2ρ_a/c). Parameters of the emitted wave were measured. The experimental data are consistent with the calculated emitted-wave parameters that take into account radiation reflection from the conducting walls of the laboratory. The efficiency of transformation of drive pulse energy into ultra-wideband radiation was found to be approximately 15%. A ring antenna driven by repetitive current pulses (within the time τ≤2ρ_a/c) is suggested to be used as a reference ultra-wideband emitter.     

Purification of baddeleyite concentrate by alloying with sulfuric acid and its salts

The conditions for the sulfation of rough baddeleyite concentrate to remove impurity minerals were studied.     

Complexes of poly-N-vinylpyrrolidone with sulfonated tetraphenylporphins

The interaction of sulfonated tetraphenylporphins H₂ TPPS₄(HCl)₂ and in CuTPPS₄ with poly-N-vinylpyrrolidone (PVP) is studied using small-angle neutron scattering, dynamic light scattering, visible spectrophotometry, and viscometry. It is shown that porphyrin molecules form complexes with PVP, thus charging the polymeric chain.