MODULAR CHEMICAL ANALYSIS SYSTEM

The modular chemical analysis system includes a first module or sample preparation apparatus for preparing sample solutions, a second module including a nephelometer apparatus comprising a stationary flow cell, mechanisms for moving sample solutions into and out of the flow cell, light generating means for passing light through the flow cell, electronic circuitry for sensing the relative light scattered(R.L.S.) by the solution or particles in the solution in the flow cell and a third module comprising a microprocessing/ calculator having a tape cartridge program. The microprocessor is coupled to the nephelometer apparatus (and, if desired, is also coupled to the sample preparation apparatus) for controlling operation of the nepheloneter apparatus (and, if desired, to control the sample preparation apparatus). Also, the output from the nephelometer apparatus is coupled to the microprocessor which receives R.L.S. values and known concentration values for some solutions from which R.L.S. values were obtained. The microprocessor then calculates curve fit parameters for a polynomial regression curve equation, performs a Newton-Raphson inversion on the equation and calculated parameters to automatically calculate concentration values for R.L.S. values obtained from unknown test solutions thereby to obtain calculated concentration values from R.L.S. measurements.