Anvils allow you to rename items, repair enchanted items, and even combine the enchantments from different items, at the cost of experience points. Crafting. You'll need 3 blocks of iron, plus 4 more iron bars, for a total of 31 iron bars.
Passivation is the treatment of the surface of stainless steels, often with acid solutions (or pastes), to remove contaminants and promote the formation of the passive film on a freshly created surface (e.g. through grinding, machining or mechanical damage).
Inactivation and closure is an intrinsic property of that type of calcium channel, and the channels do not REACTIVATE until the cell returns to being polarized once again. This inactivation is what limits the amount of calcium flux INTO the cell, which as mentioned in the other answer can be toxic to the cell.