Abstract: A process is provided for cleaning, disinfecting, and sterilizing substrates comprising the steps of: (a) placing the contaminated substrate in a cleaning vessel; (b) contacting the contaminated substrate with dense phase carbon dioxide in liquid form; (c) subjecting the substrate and the dense phase carbon dioxide to ultraviolet radiation having a wavelength within the range of about 180 to 300 nm for a duration and intensity sufficient to produce a photochemical reaction capable of destroying the DNA of microorganisms on the substrate; (d) substantially simultaneously subjecting at least the dense phase carbon dioxide to agitation; and (e) removing the dense phase carbon dioxide from the cleaning vessel and thereby transporting the contaminants from the substrate such that the substrate is cleaned and, in the case of contaminated garments, disinfected or, in the case of medical and dental instrumentation, sterilized.

Abstract: Solidifiable petroleum wax is placed in liquid form to solidify on the surface of a pond, such as a degradant lagoon for deterring emanation of malodorous gases or collecting malodorous or energy latent gases, or a reservoir to deter evaporation. The entire cover can be of liquid solidified in situ on the surface of the pond or a sheet cover can be formed by placing solidifiable buoyant material in liquid form between premolded solid cover sections or cakes to which the liquid can bond in solidifying to join adjacent premolded sections. The premolded cakes and/or the buoyant material solidified in situ can include reinforcement, such as net, which preferably also is buoyant. A suitable solidifiable buoyant material is petroleum wax which can include woody material such as sawdust or shavings, serving as an adsorbent, filler and/or vehicle for treating materials, and/or other additives such as oxidizer material, deodorant material, catalysts, enzymes and/or nutrients for anaerobic bacteria.