Abstract: Apparatus and methods for measuring the concentrations of organic and inorganic carbon, or of other materials in aqueous samples are described, having a reactor that is resistively heated by passing an electric current through the reactor.

Abstract: A conductivity meter for measuring the conductivity of a fluid is provided. The conductivity meter has a cell circuit and a control unit circuit. The cell circuit has a square wave drive amp, a cell, and a trans-impedance amplifier. The fluid flows through the cell. The control unit circuit and the square wave drive amp are configured to apply a square wave pulse train having a voltage to the fluid of the cell, thereby inducing a flow of current through the fluid in the cell. The cell circuit trans-impedance amplifier and the control unit circuit are configured to obtain a plurality of measurements of current flowing through the fluid in the cell and estimate a raw conductivity of the fluid in the cell using the current flow measurements. A method for measuring the conductivity of a fluid is also provided.

Abstract: A conductivity meter for measuring the conductivity of a fluid is provided. The conductivity meter has a cell circuit and a control unit circuit. The cell circuit has a square wave drive amp, a cell, and a trans-impedance amplifier. The fluid flows through the cell. The control unit circuit and the square wave drive amp are configured to apply a square wave pulse train having a voltage to the fluid of the cell, thereby inducing a flow of current through the fluid in the cell. The cell circuit trans-impedance amplifier and the control unit circuit are configured to obtain a plurality of measurements of current flowing through the fluid in the cell and estimate a raw conductivity of the fluid in the cell using the current flow measurements. A method for measuring the conductivity of a fluid is also provided.

Abstract: Methods and apparatus (50) are disclosed for accurately measuring low concentrations of boron in deionized water utilizing the chemical reaction of boric acid with a polyol by injecting very small plugs of concentrated polyol into streams of boron containing and non-boron containing water samples to produce an ionized acids product, and then measuring the conductivity difference (delta conductivity), corrected for interfering or extraneous factors which can effect conductivity, between such boron containing and non-boron containing samples using a conductivity and temperature detector (23).

Abstract: Methods and apparatus (50) are disclosed for accurately measuring low concentrations of boron in deionized water utilizing the chemical reaction of boric acid with a polyol by injecting very small plugs of concentrated polyol into streams of boron containing and non-boron containing water samples to produce an ionized acids product, and then measuring the conductivity difference (delta conductivity), corrected for interfering or extraneous factors which can effect conductivity, between such boron containing and non-boron containing samples using a conductivity and temperature detector (23).

Abstract: Apparatus and methods for determining the content of total organic carbon, total inorganic carbon, total carbon and total heteroorganic carbon in water are disclosed. In a preferred comprehensive embodiment, the water sample is split into a first stream and a second stream. Inorganic carbon in the first stream, if any, is determined by acidifying the sample, measuring the electrical conductivity using a temperature and conductivity sensor, and removing the ionic species. Organic carbon in the first stream is then substantially completely oxidized in a U.V. oxidation reactor to carbon dioxide and possibly other oxidation products, and the electrical conductivity of the effluent- stream is measured using another temperature and conductivity sensor. At least a portion of the carbon dioxide in the first stream is transferred through a carbon dioxide permeable membrane into the second strewn. The second stream then passes into another temperature and conductivity sensor and conductivity is measured.

Abstract: An improved apparatus and method is disclosed utilizing hydrogen absorption in combination with photolysis and/or electrolysis for in situ generation, i.e., without the need for adding chemical oxidizing agents, or enhancement of oxidizing conditions used to promote oxidation of organic compounds to form carbon dioxide, and the use of the same in connection with high-accuracy determination of even extremely low levels of organic and/or inorganic carbon compounds both in flowing aqueous streams and in bulk solutions.

Abstract: An oxidation reactor having particular utility in a system for measuring carbon in an aqueous sample. A first chamber and second chamber are separated by a hydrogen-permeable electrode, each chamber having a separate electrolysis cell. The hydrogen-permeable electrode acts as the anode of one cell and the cathode of the other cell. The sample stream flows into one chamber and the electrolysis cell produces oxygen from the water at one optically transparent electrode and in combination with short wave ultraviolet light oxidizes organic carbon to CO.sub.2 and produces hydrogen at the other electrode which passes through the hydrogen-permeable electrode into the second chamber. The electrolysis cell in the second chamber produces oxygen at hydrogen-permeable electrode to react with the hydrogen that passes through the hydrogen-permeable electrode to form water, thereby maintaining the maximum concentration gradient of hydrogen across the hydrogen-permeable electrode to improve hydrogen transferring efficiency.