In this paper we mainly study the relation between |A|^2, |H|^2 and cosα (α is the Kähler angle) of the blow up flow around the type II singularities of a symplectic mean curvature flow. We also study similar property of an almost calibrated Lagrangian mean curvature flow. We show the nonexistence of type II blow-up flows for a symplectic mean curvature flow satisfying |A|^2≤λ|H|^2 and cosα≥δ>1-\frac{1}{2λ}(½≤α≤ 2), or for an almost calibrated Lagrangian mean curvature flow satisfying |A|^2≤λ|H|^2 and cosθ≥δ>max{0,1-\frac{1}{λ}}(\frac34≤λ≤ 2), where θ is the Lagrangian angle.

}, issn = {2079-732X}, doi = {https://doi.org/10.4208/jpde.v25.n3.1}, url = {http://global-sci.org/intro/article_detail/jpde/5183.html} }