When the instrument was used to determine samples of lower abundance( 235 U abundance less than 1%),the accuracy is poor (relative bias 1%) due to the secondary electrons and strong peak tails of the instrument.

Purpose: In order to assess the angiogenesis of hepatocellular carcinoma, the peak intensity in contrast ultrasonography of the lesions was compared with the findings of immunohistochemistry.

Objective: To study the peak intensity in contrast ultrasonography of hepatocellular carcinoma and its relationship with angiogenesis and to provide a wound-less index for angiogenesis evaluation in clinic.

By numerical analysis method,influences of beam separation distance,characteristics of unit beam and array structure on far field peak intensity and beam quality of incoherent combination and the same phase coherent combination were researched.

Research results:Residual strength of slip soil has linear regression with peak strength;plastic index can be better used to estimate residual strength.

A modified Ashby-Hallam model was used to calculate the peak strength of granite specimens containing flaws.

Joint was treated as quadrate elements of ideal plastic material beyond peak strength.

This kind of dynamic effect is caused by elastic rocky impulse and peak-residual strength drop on reverse slope of stratified rocks while the locked-up segment of slope rockmass is sharply cut off.