5 B_9 nanocrystalline alloy, we proposed a model for exploring the influence of the mesoscopic structure on the soft magntic properties of this kind of Fe-based nanocrystalline alloys, and calculate the frequency function—D-function for the soft magntic properties of Fe_ 73.

Distingnishing again on the extreme point of binary function;

A Talk of The Relation of Certain Concepts In Binary Function Differential Calculus;

This paper defines a binary function related to Schwarz inequation,investigates its properties and gives some refinements for Schwarz inequation.

Experimental result shows that the non-uniform flux of open channel is single-valued corresponding to the opening angle of the plate and water depth in front of the plate,and satisfies the dualistic function.

The concept of partial derivative & directional derivative of multivariate function is presented for deducing the directional derivative & geometric meaning of Dualistic function.

Rolle theorem and Lagrange mean value theorem are improved in the case of two variable function, and the geometric meaning is given.

This paper gives out a sufficient and solution of quadratic function s maximum with theory of quadratic form and gives out the define of the positive d efinite property of the following homogeneous polynomial of degree 2n two varia ble function ,based on the definite of local maximum of two variable function i s derived .