In order to study the mechanical behaviour of frozen soil under the roadbed of the Qinghai-Tibet Railway and explore a new method to estimate the uniaxial compressive strength quickly and correctly,the stress-strain-electrical resistivity experiments for the clay in Beilu River are done under different temperatures during the whole process of uniaxial compression.

In situ measuring electronic-resistance strains of Sn-3.5Ag solder joints creep;

The dissertation performs systemic study on the electronic-resistance strains of Sn-3.

Secondly, the full bridge sensor of strain gauge is designed.

Failure analysis of lead-free solder joints based on resistance strain critical point

The resistance strain of solder joints with different thickness (0.

5Ag),as the test objects,a creep resistance test system based on the equivalent mode of resistance strain and crack developing is designed to test the resistance strain and observe the shear creep quality of solder joints,with in-situ micro electronic-resistance measurement using four-probe techniques.

In this paper,a series of carbon nanofibers/epoxy resin composite samples were fabricated,and the resistance-strain behavior was researched,as the result,the carbon nanofibers composite showed superior sensor property.

Based on the theory of dual laterolog and dual induction log response,this pap er brings up an available method that we can identify oil and water layers with deep investigation laterolog and deep induction resistivity values according to the log response features of a reservoir in shallow and middle layers.

Because of the difference between salinity (resistivity) of the formation water and the mud filtrate, the mud filtrate invasion results in the resistivity changes of the invaded zone, thus affecting the measuring result of the formation induction resistivity.