A method for process monitoring and control of a chemical reactor in which a chemical reaction utilizing a halogenated selectivity modifier is performed includes: measuring a level of halogenated components in an inlet stream of a reactor inlet; measuring a level of halogenated components in an outlet stream of a reactor outlet; based on the level of halogenated components at the inlet stream and the outlet stream, determining a process performance indicator associated with a halogenated component; and adjusting an amount of halogenated selectivity modifier added to the reactor based on the process performance indicator.

Provided is a method for measuring the concentration of aliphatic hydroxy oxime and neodecanoic acid using gas chromatography. The method includes the steps of: (a) removing, from a reference material containing an extractant and a diluent, the diluent using a silica column; (b) generating a calibration curve by calculating each peak area of aliphatic hydroxy oxime and neodecanoic acid, which are extractants, by peak integration of gas chromatograms; and (c) calculating the peak area of the organic solvent used in DSX process through the steps (a) and (b) and comparing the peak area with the calibration curve of the step (b) to measure the concentration of aliphatic hydroxy oxime and neodecanoic acid.

A system for providing standard mixtures of volatile and semi-volatile organic compounds for simultaneous GC and MS calibration in a calibration vial, wherein calibration mixtures are prepared by diluting calibration analytes in granular PDMS such that most of the analytes are in the PDMS phase and the sample can then be taken from the analytes in the headspace vapor in the calibration vial, wherein a reliable calibration sample can be taken from the calibration vial because the analytes in the PDMS phase and the headspace vapor are in thermodynamic equilibrium, and wherein the method provides solvent-less sampling, long-time stability, ease of use, is quantifiable, and related to temperature.

There is provided a method and a corresponding system for determining binding capacities of a chromatography column. The method includes detecting a feed signal representative of the composition of a feed material provided to the inlet of the column. The method further includes detecting an effluent signal representative of the composition of the effluent from the column. The method further includes using the feed signal and the effluent signal to determine binding capacities of the column.

A method of detecting gas includes determining and storing, by a controller, a zero level of a photoionization detector using ambient air inflow when an ultraviolet lamp is in a turned OFF state, wherein the stored zero level is based on an ambient temperature; sampling, by the controller, an output of a detector electrode of the photoionization detector when the ultraviolet lamp is in a turned ON state; and comparing the sampled output of the detector electrode to the stored zero level to determine if a threshold concentration of a gas is present.

A method in a separation system including parallel fluid paths each having a separation module, includes providing a sensor of the same type in at least each of the parallel fluid paths except one: measuring a characteristic fluid property with at least one of the sensors in the parallel fluid paths; possibly measuring the same characteristic fluid property with a system sensor positioned in the outlet of the separation system; and comparing measured characteristic fluid properties to evaluate and/or qualify the performance of the separation system.

A method of calibrating, a chromatography system is described. The method includes injecting a standard into a chromatographic separator. The standard including a first analyte having a first calibrant concentration and a second analyte having a second calibrant concentration. The standard can be separated in the chromatographic separator and measured with a detector. The method automatically identifies whether the first peak corresponds to the first analyte or the second analyte and whether the second peak corresponds to the first analyte or the second analyte, based on either an area or a peak height of the first peak and the second peak, and a ratio based on the first calibrant concentration and the second calibrant concentration.

Provided herein are definitive screening techniques for qualitatively and quantitatively detecting analytes in biological specimens.

A method, apparatus, and computer-readable storage medium for analyzing component separation/mass spectrometer data for a sample having known characteristic includes analyzing reference ion data for a relationship between ion mass, retention time, and intensity. The analyzed data is added to a repository, wherein each ion therein has an intensity maxima within a characteristic retention time range for a characteristic ion mass. If the reference ion is in the repository, the range is modified according to the characteristic retention time of the reference ion intensity maxima. Based on the known characteristic, an ion expected in the sample is selected from the repository, and sample data is compared to data for the ion selected from the repository to determine whether the ion is present in the sample. The range in the repository is then modified according to the characteristic retention time of the intensity maxima for the ion present in the sample.

A method of detecting gas with a photoionization detector (PID) system. The method includes powering on a photoionization detector, turning off an ultraviolet lamp of the photoionization detector by a controller of the PID system and keeping it turned off during the zero calibration procedure, flowing ambient air from a surrounding environment by a fan of the photoionization detector system past a detector electrode of the photoionization detector, processing an output of the detector electrode by the controller to determine a zero level of the photoionization detector, and storing the zero level in a memory of the photoionization detector system. The photoionization detector system in a detecting mode compares an output of the detector electrode to the zero level to determine if a threshold concentration of a gas is present.