Solitons: Differential equations, symmetries, and infinite-dimensional algebras
《Solitons: Differential equations, symmetries, and infinite-dimensional algebras》 · 第 86 页 · Definition 3.41(2)
A morphism $i:Z\to X$ of schemes is called a closed immersion, if the underlying continuous map is a homeomorphism between $Z$ and a closed subset of $X$, and the sheaf homomorphism $i^\sharp:\mathcal O_X\to i_*\mathcal O_Z$ is surjective.