Abstract: An ion selective electrode sensor includes a housing containing an internal solution and enclosing a reference element containing a metal salt solution; open mesh fabric sieves traversing an opening in the housing; and at least one ion sensitive film layer on the mesh fabric sieves.

Abstract: An ion selective electrode sensor includes a housing containing an internal solution and enclosing a reference element containing a metal salt solution; open mesh fabric sieves traversing an opening in the housing; and at least one ion sensitive film layer on the mesh fabric sieves.

Abstract: The present invention relates to apparatus and a method for measuring ammonia in biochemical processes, and more particularly to apparatus for real time measuring the amount of ammonia in a liquid with or without suspended solids.

Abstract: The invention relates to apparatus and a method for measuring NOx in biochemical processes, and to apparatus and methods for real time measuring the nitrification and/or denitrification rate of a liquid with or without suspended solids.

Abstract: The present invention relates to apparatus and a method for measuring ammonia in biochemical processes, and more particularly to apparatus for real time measuring the amount of ammonia in a liquid with or without suspended solids.

Abstract: A method of determining denitrification time for at least a portion of wastewater in a wastewater treatment process including isolating a wastewater sample from the wastewater in the wastewater treatment process; detecting changes in fluorescence emitted by NADH from microorganisms contained within the sample; detecting changes in pH of the sample; analyzing the changes in NADH and pH and establishing that the sample is denitrified at a point where NADH shifts from a steady state or a decreasing state to an increasing state and, substantially simultaneously, the pH shifts from a steady state or an increasing state to a decreasing state; and calculating elapsed time between when the sample was taken and when the sample was denitrified to determine the denitrification time for the portion of the wastewater treatment process.

Abstract: A method for measuring NO.sub.x in biochemical processes which includes a) isolating a liquid sample; b) adjusting the pH or ionic strength of the sample; c) recording mV values present in the sample after predetermined time periods; d) determining NO.sub.x concentrations in the sample at each of the predetermined time periods from the mV values; e) determining the difference in NO.sub.x in the sample from the NO.sub.x concentrations at each of the predetermined time periods; and f) determining the NO.sub.x concentration of the liquid sample from the difference in NO.sub.x and the predetermined time periods.

Abstract: A method of monitoring a microbiological process in a fluid supply involving isolation of a fluid sample from a fluid supply, measuring the pH of the fluid sample at selected time intervals, then calculating changes in pH, if any, to determine a pH variation rate for the sample. The dissolved oxygen in the sample is also measured at selected time intervals substantially synchronously with the pH measurements, and changes in dissolved oxygen, if any, are calculated to determine a biological oxygen consumption rate for the sample.

Abstract: A method of monitoring a microbiological process in a fluid supply involving isolation of a fluid sample from a fluid supply, measuring the pH of the fluid sample at selected time intervals, then analyzing changes in pH, if any, to determine a pH production rate for the sample. Changes in pH production rate are then analyzed to determine when the pH production rate changes from a negative value to zero and/or to zero for the second time as an indicator of nitrification time.

Abstract: Apparatus which monitors and controls biological activity of wastewater under anaerobic, anoxic and aerobic conditions by measuring changes in dissolved oxygen content of the wastewater and/or cellular NADH. A wastewater treatment system is controlled in accordance with the results generated by the monitoring system.

Abstract: Apparatus which monitors and controls biological activity of mixed liquor under anaerobic, anoxic and aerobic conditions by measuring the change of intracellular NAD(P)H of the microorganisms. A wastewater treatment system is controlled in accordance with the results generated by the monitoring system.

Abstract: Apparatus and method monitors and controls biological activity of mixed liquor under anaerobic, anoxic and aerobic conditions by measuring the change of intracellular AND(P)H of the microorganisms. A wastewater treatment system is controlled in accordance with the results generated by the monitoring system.