摘要:
A data manipulation method to make local chromatography data more usable and comparable to a reference. The method provides time axis correction to better match local data to a reference of the same time scale, time axis transformation to correspond more directly to a reference based on a different time scale, and response axis correction to better match a reference of the same or different response scale, while maintaining the original peak areas. The method may be used along or concurrently with other data manipulation technique to facilitate operations such as searching, matching, visual comparison, mathematical manipulation, and pattern recognition of chromatographic data.
摘要:
A data manipulation method to make local chromatography data more usable and comparable to a reference. The method provides time axis correction to better match local data to a reference of the same time scale, time axis transformation to correspond more directly to a reference based on a different time scale, and response axis correction to better match a reference of the same or different response scale, while maintaining the original peak areas. The method may be used along or concurrently with other data manipulation technique to facilitate operations such as searching, matching, visual comparison, mathematical manipulation, and pattern recognition of chromatographic data.
摘要:
A method, apparatus, and article of manufacture for enhanced integration of signals, such as those generated by chromatographs. In one embodiment an approximate baseline used for integration of a signal is improved to reduce error. Alternate embodiments filter drift, noise, or both from a signal prior to integration or simulated distillation. The signals are processed according to a computer program stored in a memory. The methods include steps for subtracting an approximate baseline from the signal, defining a noise band in the resulting difference, and forming a composite baseline by substituting signal data for baseline data wherever the difference does not exceed the threshold, thus leaving the parts of the approximate baseline that correspond to signal peaks unchanged.
摘要:
Methods and apparatus for extracting sample components from complex matrices using supercritical carbon dioxide as the principal extracting solvent are disclosed. The present invention takes advantage of the fact that the solvent power of a supercritical fluid is stepwise settable by the parameters of density, modifier concentration, and temperature. Accordingly, methods and apparatus for extracting a component from a sample using flow system having a variable and controllable flow restriction are disclosed. The methods of the present invention comprise the steps of inserting the sample into the sample container section, inputting temperature, pressure, flow rate and extraction time setpoints. The flow rate is controlled and the system pressure regulated by the variable flow restriction. The present invention contemplates opening and closing the orifice in order to control the variable flow restriction, or closing the orifice until setpoint pressure is achieved and controlling the restriction of the orifice to maintain the setpoint pressure.The present invention also discloses apparatus for the extraction of components from a sample which include means for regulating the pressure and flowrate of a supercritical extraction solvent.
摘要:
Methods and apparatus for extracting sample components from complex matrices using supercritical fluid as the principal extracting solvent are disclosed. The invention takes advantage of the fact that the solvent power of a supercritical fluid is stepwise settable by the parameters of density, modifier concentration, and temperature. Accordingly, methods and apparatus for extracting a component from a sample using fluid flow system having a variable and controllable flow restriction are disclosed. The methods of the present invention comprise the steps of inserting the sample into the sample container section, inputting temperature, pressure, flow rate and extraction time set points. Flow rate is controlled and system pressure regulated by the variable flow restriction. The invention contemplates opening and closing an orifice in order to control the variable flow restriction, or closing the orifice until set point pressure is achieved and controlling the restriction of the orifice to maintain the set point pressure. The present invention also discloses apparatus for the extraction of components from a sample which include means for regulating the pressure and flow rate of a supercritical extraction solvent.
摘要:
An instrument is disclosed which performs measurements and calculates the average and the variance of the measurements. The particular instrument illustrating the invention is a spectrophotometer which measures sets of dark, reference and sample spectra for use in calculating an average absorbance spectrum and its variance. The measurements are performed in an order which enables the cancellation of measurement variation due to variation in instrument response. The order of measurements is determined by measurement subroutines which can be aggregated to produce a series of measurements performed over a user selected period of integration time.
摘要:
A system for controlling fluid flow comprises a first fluid conduit having a length, an inner diameter, an input pressure and an output pressure, and a second fluid conduit having a length, an inner diameter, an input pressure and an output pressure where the output pressure of the first fluid conduit is the input pressure of the second fluid conduit. The system also comprises a pressure sensor configured to determine the output pressure of the first fluid conduit, and a controller configured to control the output pressure of the first fluid conduit, thereby establishing a desired fluid flow through the second fluid conduit based on the length of the second fluid conduit, the inner diameter of the second fluid conduit, the temperature of the second fluid conduit and the type of fluid flowing in the second fluid conduit.
摘要:
An instrument is disclosed which performs measurements and calculates the average and the variance of the measurements. The particular instrument illustrating the invention is a spectrophotometer which measures sets of dark, reference and sample spectra for use in calculating an average absorbance spectrum and its variance. The measurements are performed in an order which enables the cancellation of measurement variation due to variation in instrument response. The order of measurements is determined by measurement subroutines which can be aggregated to produce a series of measurements performed over a user selected period of integration time.
摘要:
Methods and apparatus for extracting sample components from complex matrices using supercritical fluid as the principal extracting solvent are disclosed. The invention takes advantage of the fact that the solvent power of a supercritical fluid is stepwise settable by the parameters of density, modifier concentration, and temperature. Accordingly, methods and apparatus for extracting a component from a sample using fluid flow system having a variable and controllable flow restriction are disclosed. The methods of the present invention comprise the steps of inserting the sample into the sample container section, inputting temperature, pressure, flow rate and extraction time set points. Flow rate is controlled and system pressure regulated by the variable flow restriction. The output stream from the extraction is then expanded through a nozzle and into a trap. In certain embodiments, the trap is filled with chemically active packing material. In other embodiments, a fractionation zone and other analytical instruments are coupled to the apparatus of the present invention. Methods and apparatus for rinsing the extraction instrument and for diluting the extraction fluid are also disclosed. Methods for operating a supercritical fluid extraction systems comprising a pressure and thermal control systems which are programmable to regulate the system to maintain such values within the design specifications during the extraction process.
摘要:
Methods and apparatus for extracting sample components from complex matrices using supercritical fluid as the principal extracting solvent are disclosed. The invention takes advantage of the fact that the solvent power of a supercritical fluid is stepwise settable by the parameters of density, modifier concentration, and temperature. Accordingly, methods and apparatus for extracting a component from a sample using fluid flow system having a variable and controllable flow restriction are disclosed. The methods of the present invention comprise the steps of inserting the sample into the sample container section, inputting temperature, pressure, flow rate and extraction time set points. Flow rate is controlled and system pressure regulated by the variable flow restriction. The output stream from the extraction is then expanded through a nozzle and into a trap. In certain embodiments, the trap is filled with chemically active packing material. In other embodiments, a fractionation zone and other analytical instruments are coupled to the apparatus of the present invention. Methods and apparatus for rinsing the extraction instrument and for diluting the extraction fluid are also disclosed. Methods for operating a supercritical fluid extraction systems comprising a pressure and thermal control systems which are programmable to regulate the system to maintain such values within the design specifications during the extraction process are also disclosed.