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Abstract Let H $\mathcal{H}$ be a k-uniform hypergraph on n vertices with degree sequence Δ=d1≥⋯≥dn=δ $\Delta=d_{1} \geq\cdots\geq d_{n}=\delta$. In this paper, in terms of degree di $d_{i}$, we give a new upper bound for the Z-spectral radius of the adjacency tensor of H $\mathcal{H}$. Some examples are given to show the efficiency of the bound.

Abstract In this paper, we give some new sharp upper and lower bounds for the spectral radius of a nonnegative irreducible matrix. Using these bounds, we obtain some new and improved bounds for the signless Laplacian spectral radius of a graph or a digraph.

Abstract In this paper, for a given matrix A = ( a i j ) ∈ C n × n $A=(a_{ij}) \in\mathbb{C}^{n\times n}$ , in terms of r i $r_{i}$ and c i $c_{i}$ , where r i = ∑ j = 1 , j ≠ i n | a i j | $r_{i} = \sum _{j = 1,j \ne i}^{n} {\vert {a_{ij} } \vert }$ , c i = ∑ j = 1 , j ≠ i n | a j i | $c_{i} = \sum _{j = 1,j \ne i}^{n} {\vert {a_{ji} } \vert }$ , some new inclusion sets for singular values of the matrix are established. It is proved that the new inclusion sets are tighter than the Geršgorin-type sets (Qi in Linear Algebra Appl. 56:105-119, 1984) and the Brauer-type sets (Li in Comput. Math. Appl. 37:9-15, 1999). A numerical experiment shows the efficiency of our new results.