A Co2 -Selective Poly(vinyl chloride) Membrane Electrode Based on a Newly Synthesized 3 3 -(Dodecylazanediyl)bis(N-(2-(2-aminoethylamino)ethyl)propanamide) Synthesized 3 3 -(Dodecylazanediyl)bis(N-(2-(2-aminoethylamino)ethyl)propanamide) compound