An Analog Computer to Simulate Systems of Coupled Bimolecular Reactions

An analog computer has been constructed to simulate, as nearly as possible, the flux of material in systems of coupled chemical reactions. Concentrations of various reactants, intermediates, and products are represented by the potentials at the outputs of electronic integrators. Rates of turnover of materials are represented by charges flowing to and from the integrators. The charges are caused to circulate by means of a "pump" mechanism that transfers charge at a rate proportional to the triple product of three voltages, two of which are derived from integrators and represent the concentrations of reactants. The third represents a rate constant. One voltage controls the frequency of an oscillator, the second, the duration of a triangular waveform, which is triggered by the oscillator, and the third, its rate of rise. By suitable interconnection of a number of integrators and pumps, a wide variety of reaction schemes can be simulated.