A new method was set up to determine the arsenic, selenium and tellurium in sulphur by the graphite fumaee a-tomic absorption spectrometry by means of the sample being solved with HNO3 in the pressure vessel.

On the basis of the calculation of compressed roller area and the rubber rigidity test, the authors give a method of calculating the elastic pressure of offset rollers and the waveform of time domain.

After a lot of EHL numerical calculations have been done with improved inverse method,this paper advances a formula used to compute the maximum contact stress on tooth surface and a criterion parameter which can be used to distinguish the difference degree between EHL pressure and Hertz stress.