Abstract: An internal combustion engine is equipped with an air line for admitting supplementary air to the induction manifold or the exhaust manifold in order to compensate for an intentional air deficiency, so as to make the mixture stoichiometric. The air line is throttled by a pneumatically activated throttle valve which is subject to at least two control pressures, one of these being the atmosphere or a constant pressure and the other being, for example, the induction tube vacuum. The termini of the two lines which admit these control pressures are so disposed in the valve as to be jointly openable and closable, in opposite phase, by an electromagnetically controlled valve-closing leaf-spring. The electromagnet is energized by a current of variable frequency, the frequency being dependent on the exhaust gas composition as monitored by an oxygen sensor.

Abstract: Process for fixing prints with reactive dyestuffs on textile materials of native or regenerated fibers and fiber mixtures which contain such fibers in admixture with synthetic fibers, which process comprises printing reactive dyestuffs having the usual printing paste composition on the textile material, drying, impregnating with an alkali mixture of liquid alkali water glass of 37.degree.-52.degree. Be and concentrated sodium hydroxide solution of 38.degree.-50.degree. Be at pH 10-14, preferably 11-12, and fixing. By this process the drawbacks of using either a sodium hydroxide soluion or liquid alkali water glass alone are avoided. The fixing solution is rendered more fluid to such an extent that less liquor is consumed, the heating of the liquor is made superfluous, deposits on the rolls are avoided, the material to be printed is more rapidly wetted, the fabric webs do not dry on or stick together during the dwelling periods and thus the process is rendered more economical in total.