The light intensity distribution exhibits straw hat shape on a certain conditions, in other word to say, the central light intensity is less than acroteric light intensity.
The cross section morphology and skin-core structure of PAN fiber in wet-spinning are analyzed by the means of electron probe microanalyser (EPMA) and scanning electron microscope (SEM).
Counterfort retaining walls are optimized in the paper, using the optimum program, costs of different counterfort retaining wall parameters were calculated and based on the contrast analysis.
Ends of the tegular filters (10) are cut off crosswise to make the end surfaces respectively form inclined surfaces such that vertical sections of the tegular filters (10) are in a rough trapezoid.