Method of dechroming leathers and/or leather waste tanned withic chromium compounds or other substances containing chromium compounds, in particular wastes of collagen origin
PL313842A1
Method of eliminating methanol and formaldehyde from waste waters
PL313646A1
Method of producing foamed melamine material
PL313645A1
Method of obtaining plastic materials and plastic materials obtained thereby
PL312117A1
Plasticising system of an injection moulding machine
PL309299A1
Method of treating dye-house waste waters
PL307794A1
Method of an dtool for smoothening flat surfaces
PL307659A1
Stepping motor feeder circuit
PL307660A1
Blinking interrupter for road-crossing warning lights
PL306895A1
System for protecting a storage battery against excessive discharging
PL306894A1
System for protecting a storage battery against overcharging
PL305335A1
Modified poly(vinyl chlorode), method of obtaining same and leather-like materials containing it
PL303798A1
Method of measuring rail-vehicle speed and system therefor
PL301749A1
Abrasive tool with single layer of abrasive particles
