Abstract: A method for selective removal of polycyclic aromatic hydrocarbons from oils obtained as a result of petroleum processing, including two separate processes: filtration through a porous carbon-containing bed comprising and filtration through microfiltration membranes. The method is particularly useful for purifying oils selected from unconverted oils obtained in hydrocracking processes, products of further processing of these oils, engine oil and used engine oil.

Abstract: A generator for dynamic loading of a mine lining simulates an unstable ground structure, such as a "bump" of the formation roof by an explosion of an explosive. The generator /3/ comprises a cylinder /6/ with a piston /7/, the said piston functioning as a percussion member. The bottom of the cylinder /6/ is provided with symmetrical chambers /10/ to place an explosive. The explosive is batched to each of chambers /10/ through holes /8, 9/ made in the flank of the cylinder /6/. Holes /8, 9/ are bored at an angle enabling gravitational filling of the chamber /10/ with an explosive already after initial spragging of the lining section /1/ under test between the floor /2/ and the generator /3/ abutting the roof /5/ of the test-stand. The cylinder /6/ is closed with a limiter /12/ of the stroke of the piston. Between the piston /7/ and the limiter /12/ of its stroke there is a shock-absorbing washer /13/. In the limiter /12/ there are additional holes for release of powder gases.