Abstract: To provide a semiconductive roller which, when being used as a developing roller in combination with a positively chargeable toner, is capable of suppressing adhesion of the toner thereto to suppress reduction of image density, charging the toner to a higher toner charging level to ensure formation of higher-quality images, and suppressing reduction of toner charging level even after continuous repeated image formation to thereby suppress fogging of formed images for a longer period of time. The semiconductive roller (1) is made of a crosslinking product of a rubber composition containing at least an epichlorohydrin rubber and a chloroprene rubber, and has a fluorinated film (5) formed in an outer peripheral surface (4) thereof by treatment with fluorine gas.

Abstract: A process for the pyrolysis of 1,2-dichloroethane (EDC) in a pyrolysis furnace (1) involves feeding liquid EDC into a convection heat transfer tube (2) for preheating, channeling an intermediate flow of preheated EDC into a radiation heat transfer tube (3) for further heating, thereby pyrolyzing a part of EDC into vinyl chloride monomer, and discharging a decomposition gas flow from the pyrolysis furnace. Potential heat is recovered from the decomposition gas by using a double tube type heat exchanger (10) consisting of outer and inner tubes, that is, by channeling the intermediate flow through the outer tube (11), channeling the decomposition gas through the inner tube (15) for heat exchange between the intermediate flow and the decomposition gas, and feeding the heat acquired intermediate flow into the radiation heat transfer tube (3).

Abstract: A process for the pyrolysis of 1,2-dichloroethane (EDC) in a pyrolysis furnace (1) involves feeding liquid EDC into a convection heat transfer tube (2) for preheating, channeling an intermediate flow of preheated EDC into a radiation heat transfer tube (3) for further heating, thereby pyrolyzing a part of EDC into vinyl chloride monomer, and discharging a decomposition gas flow from the pyrolysis furnace. Potential heat is recovered from the decomposition gas by using a double tube type heat exchanger (10) consisting of outer and inner tubes, that is, by channeling the intermediate flow through the outer tube (11), channeling the decomposition gas through the inner tube (15) for heat exchange between the intermediate flow and the decomposition gas, and feeding the heat acquired intermediate flow into the radiation heat transfer tube (3).

Abstract: A nozzle is formed of reaction sintered silicon carbide consisting essentially of silicon carbide and unreacted metallic silicon and having a density of 3.03-3.16 g/cm.sup.3. The nozzle satisfies the requirements of heat, wear, corrosion and chemical resistance and has experienced no volume shrinkage during sintering. The nozzle is suitable for use in a mixing/dispersing arrangement mounted in a fluidized bed reactor.