The Experts below are selected from a list of 87 Experts worldwide ranked by ideXlab platform
Bruce R. Kowalski - One of the best experts on this subject based on the ideXlab platform.
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Multicomponent Determination of Chlorinated Hydrocarbons Using a Reaction-Based Chemical Sensor. 1. Multivariate Calibration of Fujiwara Reaction Products
Analytical Chemistry, 1994Co-Authors: John M. Henshaw, Lloyd W. Burgess, Karl S. Booksh, Bruce R. KowalskiAbstract:Multicomponent analysis for 1,1,1-trichloroethane, trichloroethylene, and chloroform is demonstrated by partial least squares modeling of absorbance data collected from the Fujiwara Reaction of these analytes over time. Optimal calibration times are determined for each analyte dependent upon its Reaction rate. This is the simplest example of trying to use the selectivity gained from a second data dimension or order. Problems associated with first-order calibration are demonstrated when interferences unaccounted for in the calibration model are present
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Multicomponent Determination of Chlorinated Hydrocarbons Using a Reaction-Based Chemical Sensor. 3. Medium-Rank Second-Order Calibration with Restricted Tucker Models
Analytical Chemistry, 1994Co-Authors: Age K. Smilde, John M. Henshaw, Lloyd W. Burgess, Romà Tauler, Bruce R. KowalskiAbstract:The calibration of a chemical sensor for chlorinated hydrocarbon analytes based on the Fujiwara Reaction is described. This sensor generates a particular type of data: medium-rank second-order data. With this type of data it is possible to calibrate the sensor in such a way that quantitation for the analytes in the presence of unknown interferents is possible. The calibration method developed is a new approach based on so-called restricted Tucker models that utilize all available chemical information
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Multicomponent determination of chlorinated hydrocarbons using a Reaction-based chemical sensor.2. Chemical speciation using multivariate curve resolution.
Analytical Chemistry, 1994Co-Authors: Romà Tauler, John M. Henshaw, Lloyd W. Burgess, Age K. Smilde, Bruce R. KowalskiAbstract:A new multivariate curve resolution method that can extract analytical information from UV/visible spectroscopic data collected from a Reaction-based chemical sensor is proposed. The method is demonstrated with the determination of mixtures of chlorinated hydrocarbons by estimating the kinetic and spectral profiles of the chemical species formed in the Fujiwara Reaction. The three key aspects of the proposed method are (1) the initial estimation of the kinetic concentration profiles from evolving factor analysis; (2) the implementation of an alternating and constrained least squares method to optimize the determination of both the spectral and concentration profiles of the species present in the Reaction, and (3) the development of a quantitative approach based on the simultaneous analysis of standards and unknowns for the determination of the initial concentration of the analytes in the mixtures
John M. Henshaw - One of the best experts on this subject based on the ideXlab platform.
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Multicomponent Determination of Chlorinated Hydrocarbons Using a Reaction-Based Chemical Sensor. 1. Multivariate Calibration of Fujiwara Reaction Products
Analytical Chemistry, 1994Co-Authors: John M. Henshaw, Lloyd W. Burgess, Karl S. Booksh, Bruce R. KowalskiAbstract:Multicomponent analysis for 1,1,1-trichloroethane, trichloroethylene, and chloroform is demonstrated by partial least squares modeling of absorbance data collected from the Fujiwara Reaction of these analytes over time. Optimal calibration times are determined for each analyte dependent upon its Reaction rate. This is the simplest example of trying to use the selectivity gained from a second data dimension or order. Problems associated with first-order calibration are demonstrated when interferences unaccounted for in the calibration model are present
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Multicomponent Determination of Chlorinated Hydrocarbons Using a Reaction-Based Chemical Sensor. 3. Medium-Rank Second-Order Calibration with Restricted Tucker Models
Analytical Chemistry, 1994Co-Authors: Age K. Smilde, John M. Henshaw, Lloyd W. Burgess, Romà Tauler, Bruce R. KowalskiAbstract:The calibration of a chemical sensor for chlorinated hydrocarbon analytes based on the Fujiwara Reaction is described. This sensor generates a particular type of data: medium-rank second-order data. With this type of data it is possible to calibrate the sensor in such a way that quantitation for the analytes in the presence of unknown interferents is possible. The calibration method developed is a new approach based on so-called restricted Tucker models that utilize all available chemical information
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Multicomponent determination of chlorinated hydrocarbons using a Reaction-based chemical sensor.2. Chemical speciation using multivariate curve resolution.
Analytical Chemistry, 1994Co-Authors: Romà Tauler, John M. Henshaw, Lloyd W. Burgess, Age K. Smilde, Bruce R. KowalskiAbstract:A new multivariate curve resolution method that can extract analytical information from UV/visible spectroscopic data collected from a Reaction-based chemical sensor is proposed. The method is demonstrated with the determination of mixtures of chlorinated hydrocarbons by estimating the kinetic and spectral profiles of the chemical species formed in the Fujiwara Reaction. The three key aspects of the proposed method are (1) the initial estimation of the kinetic concentration profiles from evolving factor analysis; (2) the implementation of an alternating and constrained least squares method to optimize the determination of both the spectral and concentration profiles of the species present in the Reaction, and (3) the development of a quantitative approach based on the simultaneous analysis of standards and unknowns for the determination of the initial concentration of the analytes in the mixtures
V. K. Gupta - One of the best experts on this subject based on the ideXlab platform.
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A sensitive spectrophotometric method for determination of carbon tetrachloride
Journal of the Indian Chemical Society, 2005Co-Authors: Sukumar Chatterjee, V. K. GuptaAbstract:A sensitive spectrophotometric method for the determination of carbon tetrachloride (CTC) in ppm level is described. The method involves the modification of the Fujiwara Reaction i.e. discharging the colour with glacial acetic acid followed by addition of p-aminoacetophenone reagent which results in the formation of the purple red coloured polymethine dye having an absorption maximum at 495 nm. Beer's law is obeyed in the range of 4.0-36 μg (0.4-3.6 ppm) of carbon tetrachloride per 10 ml of solution. The sensitivity of the conventional Fujiwara procedure is increased after this modification. The method has been successfully applied for the determination of carbon tetrachloride in air, laundry air and biological samples.
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A sensitive colorimetric method for determination of chloroform
Indian Journal of Chemical Technology, 1999Co-Authors: Ajai K. Pillai, Rachana Rastogi, V. K. GuptaAbstract:A sensitive colorimetric method for determination of chloroform in ppm level is described, which is based on modification of Fujiwara Reaction i.e. colour development on treatment with pyridine and sodium hydroxide and discharging the colour with acetic acid and followed by addition of p-amino acetophenone reagent. The purple red colour formed has an absorption maximum at 520 nm. Beer's law is obeyed in the range of 1.0-10 μg (0.1 to 1.0 ppm) of chloroform per 10 mL of solution. The method is found to be free from interference of various copollutants. The sensitivity of the conventional Fujiwara procedure is increased after this modification. The method has been successfully applied for the determination of chloroform in various environmental and biological samples.
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Modified Fujiwara Reaction for the determination of trichloroacetic acid
Microchemical Journal, 1991Co-Authors: Madhusri Bhattacharjee, Lata Cherian, V. K. GuptaAbstract:Abstract A new sensitive spectrophotometric method for the determination of trichloroacetic acid (TCA) at the ppm level is described. The method involves the modification of the Fujiwara Reaction, i.e., discharging the color with acetic acid followed by the addition of sulfanilic-formic acid reagent which results in the formation of an orange-yellow-colored polymethine dye having an absorption maximum at 505 nm. The sensitivity after this modification is found to be about five times more than that of the conventional Fujiwara procedure. Beer's law is obeyed in the range of 10–100 μg (1–10 ppm) of trichloroacetic acid per 10 ml of solution. The method is found to be free from the interference of various organic compounds including carbon tetrachloride, benzene, and chloroform under the conditions employed. The method has been successfully applied for the determination of trichloroacetic acid in air, serum, and urine samples.
Lloyd W. Burgess - One of the best experts on this subject based on the ideXlab platform.
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Multicomponent Determination of Chlorinated Hydrocarbons Using a Reaction-Based Chemical Sensor. 1. Multivariate Calibration of Fujiwara Reaction Products
Analytical Chemistry, 1994Co-Authors: John M. Henshaw, Lloyd W. Burgess, Karl S. Booksh, Bruce R. KowalskiAbstract:Multicomponent analysis for 1,1,1-trichloroethane, trichloroethylene, and chloroform is demonstrated by partial least squares modeling of absorbance data collected from the Fujiwara Reaction of these analytes over time. Optimal calibration times are determined for each analyte dependent upon its Reaction rate. This is the simplest example of trying to use the selectivity gained from a second data dimension or order. Problems associated with first-order calibration are demonstrated when interferences unaccounted for in the calibration model are present
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Multicomponent Determination of Chlorinated Hydrocarbons Using a Reaction-Based Chemical Sensor. 3. Medium-Rank Second-Order Calibration with Restricted Tucker Models
Analytical Chemistry, 1994Co-Authors: Age K. Smilde, John M. Henshaw, Lloyd W. Burgess, Romà Tauler, Bruce R. KowalskiAbstract:The calibration of a chemical sensor for chlorinated hydrocarbon analytes based on the Fujiwara Reaction is described. This sensor generates a particular type of data: medium-rank second-order data. With this type of data it is possible to calibrate the sensor in such a way that quantitation for the analytes in the presence of unknown interferents is possible. The calibration method developed is a new approach based on so-called restricted Tucker models that utilize all available chemical information
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Multicomponent determination of chlorinated hydrocarbons using a Reaction-based chemical sensor.2. Chemical speciation using multivariate curve resolution.
Analytical Chemistry, 1994Co-Authors: Romà Tauler, John M. Henshaw, Lloyd W. Burgess, Age K. Smilde, Bruce R. KowalskiAbstract:A new multivariate curve resolution method that can extract analytical information from UV/visible spectroscopic data collected from a Reaction-based chemical sensor is proposed. The method is demonstrated with the determination of mixtures of chlorinated hydrocarbons by estimating the kinetic and spectral profiles of the chemical species formed in the Fujiwara Reaction. The three key aspects of the proposed method are (1) the initial estimation of the kinetic concentration profiles from evolving factor analysis; (2) the implementation of an alternating and constrained least squares method to optimize the determination of both the spectral and concentration profiles of the species present in the Reaction, and (3) the development of a quantitative approach based on the simultaneous analysis of standards and unknowns for the determination of the initial concentration of the analytes in the mixtures
Romà Tauler - One of the best experts on this subject based on the ideXlab platform.
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Multicomponent Determination of Chlorinated Hydrocarbons Using a Reaction-Based Chemical Sensor. 3. Medium-Rank Second-Order Calibration with Restricted Tucker Models
Analytical Chemistry, 1994Co-Authors: Age K. Smilde, John M. Henshaw, Lloyd W. Burgess, Romà Tauler, Bruce R. KowalskiAbstract:The calibration of a chemical sensor for chlorinated hydrocarbon analytes based on the Fujiwara Reaction is described. This sensor generates a particular type of data: medium-rank second-order data. With this type of data it is possible to calibrate the sensor in such a way that quantitation for the analytes in the presence of unknown interferents is possible. The calibration method developed is a new approach based on so-called restricted Tucker models that utilize all available chemical information
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Multicomponent determination of chlorinated hydrocarbons using a Reaction-based chemical sensor.2. Chemical speciation using multivariate curve resolution.
Analytical Chemistry, 1994Co-Authors: Romà Tauler, John M. Henshaw, Lloyd W. Burgess, Age K. Smilde, Bruce R. KowalskiAbstract:A new multivariate curve resolution method that can extract analytical information from UV/visible spectroscopic data collected from a Reaction-based chemical sensor is proposed. The method is demonstrated with the determination of mixtures of chlorinated hydrocarbons by estimating the kinetic and spectral profiles of the chemical species formed in the Fujiwara Reaction. The three key aspects of the proposed method are (1) the initial estimation of the kinetic concentration profiles from evolving factor analysis; (2) the implementation of an alternating and constrained least squares method to optimize the determination of both the spectral and concentration profiles of the species present in the Reaction, and (3) the development of a quantitative approach based on the simultaneous analysis of standards and unknowns for the determination of the initial concentration of the analytes in the mixtures
