Abstract: The process of detecting the presence on a surface of at least one of bis(2-chloroethyl)sulfide and bis(2-chloroethyl)imine, including (a) providing a solution comprising at least one dyestuff selected from the group consisting of brilliant blue R, guinea green B, neutral red, and lissamine green B, which at least one dyestuff is capable of fluorescing and is capable, when applied as a solution, of forming an adduct with at least one of bis(2-chloroethyl)sulfide and bis(2-chloroethyl)imine when present on a surface, which at least one adduct, is capable of fluorescing in a spectral range which is different from that of the corresponding at least one dyestuff; (b) applying the solution to the surface; (c) irradiating the surface onto which the solution has been applied with light having a wavelength effective to excite the at least one dyestuff and, when present, the at least one adduct, and induce light emission by fluorescence therefrom; (d) measuring the wavelength of the light emitted from the surface; and

Abstract: A process for the production of a composite membrane consisting of a porous supporting membrane and a thin separating membrane. The separating membrane is produced on the surface of a carrier film (consisting essentially of a soluble polymer). The carrier film coated with the separating membrane is placed with its separating membrane side on a porous supporting membrane such that the separating membrane is between the supporting membrane and the carrier film. The carrier film is then dissolved.