https://w3id.org/framester/conceptnet5/data/en/ybco <https://w3id.org/framester/conceptnet5/schema/RelatedTo> <https://w3id.org/framester/conceptnet5/data/en/oxygen> <https://w3id.org/framester/conceptnet5/data/en/copper> <https://w3id.org/framester/conceptnet5/data/en/superconducting> <https://w3id.org/framester/conceptnet5/data/en/barium> <https://w3id.org/framester/conceptnet5/data/en/yttrium> risorse dalla linked data cloud