Does dry impurity not affect dry purity, and does wet purity not get affected by dry impurity, regarding the impurity of urine?

If a dry pure substance meets a dry impure substance, it does not become impure. However, if a wet pure substance meets something that has become impure, it does not become impure according to the Maliki and Hanafi schools, while it does become impure according to the Shafi'i school. According to the Hanbali school, it becomes impure if it has wetness, not merely dampness. If a wet pure substance meets the essence of impurity itself, it becomes impure.