Abstract: Compositions for CO2 detector solutions and rapid-response reversible dry surface CO2 detectors made from them are disclosed. The CO2 detector solutions generally comprise a poly(oxyethylene) based compound, a pH sensitive indicator dye, an organic solvent, a cationic phase transfer agent and an anionic base. However, minimally these detector solutions comprise a poly(oxyethylene) based compound, a pH sensitive indicating dye, an organic solvent and a base. The solutions were embedded onto a solid support made of polyethersulfone filter material in order to form rapid-response reversible dry surface CO2 detectors. Rapid-response reversible dry surface CO2 detectors are produced which function at rates in excess of 180 one-way color changes/minute when exposed to alternating 0% and 5% CO2 concentrations. A preferred embodiment using cationic methyltricaprylylammonium in conjunction with the phenoxide anion is substantially humidity resistant.

Abstract: The construction of a collapsible rotary torso exercise machine is disclosed. The machine's extended parts fold down and/or detach so that it may be stored in a small space. The machine is also lightweight and therefore portable. Three different types of resistance mechanism are specifically disclosed: 1) piston in cylinder resistance 2) friction resistance and 3) elastic member resistance. The collapsible rotary torso exercise machine preferably has variable resistance and for each type of resistance mechanism disclosed, a mechanism or method for varying the resistance is also disclosed.