Through the study on the relation between number of path 2(P2),number of path 3(P3),boiling point(Tb) and flash points(Tf) of 77 alkanes and alkenes(with 2~20 carbon atoms),it is found that P2,P3 and Tb have high correlativity with Tf,the equation can be expressed as follows: Tf=0.

Experimental study on relationship among runoff coefficients of different underlying surfaces,rainfall intensity and duration;

Development of runoff coefficient forecast model under simulated rainfall;

Effect of topographic form and vegetation type on the runoff coefficient in the Xiangshuihe Watershed of Liupan Mountains

The topological index XZ,numbers of path P 1,S 1 and S 2 can be used to characterize the size,branchins and shape of saturated monobasic alcohol,and site of hydroxyl in alcohol.

The topological index x z numbers of path 1,3,4 (P 1,P 3,P 4) can be used to characterize the size,branchins and shape of alkanes.

The topological index z x ,numbers of path p, measures s 1 and s 2 can be used to characterize the size,branching and shape of fatty ether,and the site of oxy atom in ether.

To obtain the calculating formula of theoretical diameter of ramie yarn, the author tests the diameter by using the microscope projecter, determines the metric number by surveying its length and weighing it, and gets the diameter coefficient ( k =0.