Abstract: A method of continuously degassing water in which the vapor phase components melted in the water are continuously degassed by heating the water and reducing the pressure of the water. An in-line heater is used to continuously mix saturated steam into water supplied continuously, to heat said water and to accelerate the foaming of the vapor phase components melted in the water by cavitation caused by the mixing of said saturated steam. Thereafter the water is degassed automatically while being pooled in a degassing tank under atmospheric pressure.

Abstract: A catalyst for the selective reduction of nitrogen oxides in exhaust gases in the presence of ammonia is vanadium oxide supported on a specific carrier of the anatase form of titanium oxide.

Abstract: The reduction of nitrogen oxides involves the passage of gases containing nitrogen oxides at higher than 500.degree. C. over a catalyst comprising cerium oxide and nickel oxide in the CeO.sub.2 /NiO molar ratio of about 0.05 : 1 to 2.5 : 1 and when desired an addition thereto of rhodium in an amount of from about 7.5 to 25 parts by weight per 100 parts by weight of the nickel oxide and cerium oxide composition and when desired an addition to said nickel oxide and cerium oxide composition of ruthenium in an amount of about 10 to 50 parts by weight or an addition to said composition containing rhodium of ruthenium in an amount of about 15 to 50 parts by weight per 100 parts by weight of the nickel oxide and cerium oxide composition. Also, when desired, an addition to said composition of one or more metal sulfides and an addition to said composition of one or more metal oxides is utilized.