A memory system and an operating method thereof are provided. The compositions are tougher, stronger, and more scuff and abrasion resistant than typical ionomer compositions. In additional embodiments, the invention relates methods of correlating color changes of a dye to the presence or absence of hydroxyl radicals. A mechanism is further disclosed for automatically moving emails from one container to another after an email has been read. The first range includes: a central section facing the semiconductor element in the central portion in a thickness direction; and an outer edge section facing the semiconductor element in the outer edge portion in the thickness direction. The inspection system provides a phase contrast imaging unit and an inspection method using said phase contrast imaging unit designed to recognize defective lenses with an improved degree of reliability but that does not falsely sort out perfect lenses.