No known chemical by the name Pseudoproto-Pb has been recognized in scientific literature or chemical databases. As a result, there are no established applications for this substance. If this is a hypothetical, fictional, or incorrectly named compound, further clarification would be needed to provide meaningful information. In real-world chemistry, lead (Pb)-based compounds are used in batteries, radiation shielding, and certain industrial processes, but such uses do not apply here without verification of the compound’s existence and properties.