New upper bounds for graph energy

For a graph G of order n, the (ordinary) graph energy, denoted by EG, is defined as EG=∑i=1nλi, where λ1≥λ2≥⋯≥λn, are the eigenvalues of G. In this paper, new upper bounds for E(G) are presented. From two of these results, some earlier known upper bounds on E(G) could be improved.