Pyrazole has been prepared through the dehydrogenation of 2 pyrazoline in which catalytic amonts of sodium iodide acts as dehydrogenation agent in sulfuric acid.
As to metal halide torch with gallium iodide is special rise 403nm and 417nm wave crest, and the highest wave crest 417nm has conspicuousness and good effect to exposal Diazo material.