First of all, the title of the novel is actually Cien años de soledad, so we need to check the Spanish:
Buendía no trató siquiera de consolarla, entregado por entero a sus experimentos tácticos con la
abnegación de un científico y aun a riesgo de su propia vida.
And we find that the translation is word for word. Next, we need to check the context fore and aft. "His tactical experiments" (sus experimentos tácticos) are Buendía's work to make a large magnifying glass into a weapon of war. To this end, he spends his wife's money (to her despair) and seriously burns himself. This is a completely self-indulgent project, since his efforts to interest the government in his plans come to nothing. Thus abnegation in the sense of self-denial is inapt. But abnegation also means simply rejection or refusal. And in the pursuit of his "scientific" project, Buendía has rejected his wife's pleas without providing her any consolation, and he has refused to take safety precautions for himself.