A method and apparatus is provided for concentration determination of at least one component in an acid catalyst for hydrocarbon conversion containing an unknown concentration of an acid, an acid-soluble-oil (ASO), and water. An instrument configured for measuring a property of the acid catalyst, has responsivities to concentrations of one of the acid, ASO, and water, substantially independent of the concentrations of the others of the acid catalyst, ASO, and water. A temperature detector is configured to generate temperature data for the acid catalyst. A processor is configured to capture data generated by the temperature detector and the instrument, and to use the data in combination with a model to determine a temperature compensated concentration of the one of the acid, the ASO, and the water. Optionally, one or more other instruments configured for measuring other properties of the liquid mixture may also be used.

The invention is directed to a method of identifying a patient undergoing periodic hemodialysis treatments at increased risk for death that includes determining at least one of the patient's clinical or biochemical parameters, consisting of serum bicarbonate concentration level, serum potassium concentration level, serum calcium concentration level, hemoglobin concentration level, serum phosphorus concentration level, neutrophil to lymphocyte ratio, equilibrated normalized protein catabolic rate (enPCR), equilibrated fractional clearance of total body water by dialysis and residual kidney function (eKdrt/V), EPO resistance index, transferrin saturation index, serum ferritin concentration level, serum creatinine concentration level, platelet count, Aspartat-Aminotransferase level, and Alanin-Aminotransferase level at periodic hemodialysis treatments, and identifying a patient as having an increased risk for death if the patient has a significant change in the rate of change of at least one of the patient's clinical or biochemical parameters. The invention is also directed to a method of identifying an increased mortality risk factor for a patient undergoing periodic hemodialysis treatment. The method includes analyzing data of deceased patients that were previously undergoing periodic hemodialysis treatments by performing a longitudinal analysis backwards in time of changes in a clinical or biochemical parameter the patients, and identifying a significant change in the rate of decline or the rate of increase in a clinical or biochemical parameter before death of the patients.