With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Al Capone died.
text_B: Heterogenous catalytic reactors put emphasis on catalyst effectiveness factors and the heat and mass transfer implications .. catalyst. catalyst. heat. heat. mass transfer. mass transfer. Heterogenous catalytic reactors are among the most commonly utilized chemical reactors in the chemical engineering industry .
not_related.