Polycarbonate Diols (PCD) are used for a wide range of polyurethane-based coating formulations, providing an extreme durability and a high performance to the final polymer. ok
In mathematics, a reciprocity law is a generalization of the law of quadratic reciprocity. There are several different ways to express reciprocity laws.
The social norm of reciprocity is the expectation that people will respond to each other in similar waysâresponding to gifts and kindnesses from others with similar benevolence of their own, and responding to harmful, hurtful acts from others with either indifference or some form of retaliation.