The present invention aims at making it possible to successfully achieve fast recovery during magnetic resonance imaging in which the fast spin echo technique combined with the inversion recovery technique is implemented. In one embodiment, a modular roofing structure comprises a photovoltaic shingle panel having a planar lower surface and an upper surface, and a rigid back member having a length the same as or greater than the length of the shingle panel and attached to the planar lower surface of the shingle panel. After removing a residue or a natural oxide film present on the silicon film through dry etching, the silicon film is dry etched by using the hard mask as a mask. The adsorbed samples are desorbed later for analysis by a plurality of individual mass spectrometers. In addition, the present invention also provides kits and methods for screening a library of cells presenting the candidate peptides in peptide display scaffolds to identify a ligand for an enzyme. The literal symbols are collected into a group and compressed separately.