1 citations · 2 across the 4 of their papers we have counts for
11 papers
The Alternating Groups and K3 Surfaces
D. -Q. Zhang
In this note, we consider all possible extensions G of a non-trivial perfect group H acting faithfully on a K3 surface X. The pair (X, G) is proved to be uniquely determined by G i…
A Nonvanishing Theorem for Q-divisors
Jungkai Alfred Chen, Meng Chen, De-Qi Zhang
We prove a non-vanishing theorem of the cohomology H^0 of the adjoint divisor K_X + L' where L' is the round up of a nef and big Q-divisor L.
Equivariant classification of Gorenstein open log del Pezzo surfaces with finite group actions
Masayoshi Miyanishi, De-Qi Zhang
We classify equivariantly Gorenstein log del Pezzo surfaces with boundaries at infinity and with finite group actions such that the quotient surface modulo the finite group has Pic…
The determination of integral closures and geometric applications
Sheng-Li Tan, De-Qi Zhang
We express explicitly the integral closures of some ring extensions; this is done for all Bring-Jerrard extensions of any degree as well as for all general extensions of degree < 6…
On Gorenstein Surfaces Dominated by P^2
R. V. Gurjar, C. R. Pradeep, D. -Q. Zhang
In this paper we prove that a normal Gorenstein surface dominated by the projective plane P^2 is isomorphic to a quotient P^2/G, where G is a finite group of automorphisms of P^2 (…
Fundamental groups of open K3 surfaces, Enriques surfaces and Fano 3-folds
J. Keum, D. -Q. Zhang
We investigate when the fundamental group of the smooth part of a K3 surface or Enriques surface with Du Val singularities, is finite. As a corollary we give an effective upper bou…