The Experts below are selected from a list of 252 Experts worldwide ranked by ideXlab platform
Eberhard Lorbeer - One of the best experts on this subject based on the ideXlab platform.
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Investigation of combwax of honeybees with High-Temperature Gas chromatography and High-Temperature Gas chromatography-chemical ionization mass spectrometry. I. High-Temperature Gas chromatography.
Journal of Chromatography A, 1999Co-Authors: Reiner Aichholz, Eberhard LorbeerAbstract:Abstract The combwaxes of the honeybee species Apis mellifera, Apis cerana, Apis dorsata, Apis laboriosa, Apis florea and Apis andreniformis have been examined by High-Temperature Gas chromatography. Combwax consists of a complex mixture of homologous neutral lipids. These compounds containing up to 64 carbons were chromatographed intact on a 10 m×0.2 mm High-Temperature stable SOP-50-PFD (50%-diphenyl/50%-1H,1H,2H,2H-perfluorodecylmethylpolysiloxane)-coated Duran glass capillary column. The use of this stationary phase results in lower retention values and, at last, in lower thermal stress of the analytes. In order to minimize the discrimination effect due to adsorption and/or degradation, a two-step derivatization was performed resulting in the formation of tert.-butyldimethylsilyl esters of the long chain fatty acids and trimethylsilyl ethers of complex hydroxyesters, respectively. The derivatization procedure was optimized using a modification of the extended Donike test. In addition this test allows the quantification of the thermal stability of the derivatives performed. The derivatization procedure was applied for combwax analysis. More than 80 compounds were separated and their peak areas semiquantitatively exploited.
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Identification of cyclopropene triacylglycerols by High-Temperature Gas chromatography and High-Temperature Gas chromatography–negative chemical ionization mass spectrometry
Journal of Microcolumn Separations, 1999Co-Authors: Reiner Aichholz, Volker Spitzer, Eberhard LorbeerAbstract:The seed oil of Choriosa speciosa, which is known to be rich in cyclopropene triacylglycerols, has been investigated by High-Temperature Gas chromatography using glass capillary columns coated with the stationary phase SOP-50 (50% diphenyl–50% dimethylpolysiloxane, methoxy terminated). Cyclopropene rings were characterized after a mild catalyzed hydrogenation procedure. The partial π-character of the resulting cyclopropane ring supports the separation of individual triacylglycerol species on the polarizable stationary phase. Characterization of the separated compounds was performed by negative chemical ionization–mass spectrometry with ammonia as reagent Gas. ©1999 John Wiley & Sons, Inc. J Micro Sep 11: 223–229, 1999
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Analysis of cyanolipids and triacylglycerols from sapindaceae seed oils with High-Temperature Gas chromatography and High-Temperature Gas chromatography-chemical ionization mass spectrometry
Journal of Chromatography A, 1997Co-Authors: Reiner Aichholz, Volker Spitzer, Eberhard LorbeerAbstract:Abstract The seed oils of three Sapindaceae species have been examined by High-Temperature Gas chromatography using glass capillary columns coated with the stationary phases SOP-50 (50% diphenyl-50% dimethylpolysiloxane, methoxy-terminated) and OV-225-OH (25% phenylmethyl-25% cyanopropylmethylpolysiloxane, hydroxy-terminated), respectively. The cyanolipid and triacylglycerol fraction could be identified by a combination of High-Temperature Gas chromatography with a flame ionization and a nitrogen-phosphorus detector and Gas chromatography-mass spectrometry in positive and negative chemical ionization mode using NH3 and CH4/N2O as reagent Gases. The OV-225-OH phase showed better separation properties than the SOP-50 phase and up to 34 peaks could be separated. The analysis of the fatty acids in the seed oil of Allophylus edulis as their methyl esters by High-resolution GC and GC-MS are presented for the first time.
Reiner Aichholz - One of the best experts on this subject based on the ideXlab platform.
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Investigation of combwax of honeybees with High-Temperature Gas chromatography and High-Temperature Gas chromatography-chemical ionization mass spectrometry. I. High-Temperature Gas chromatography.
Journal of Chromatography A, 1999Co-Authors: Reiner Aichholz, Eberhard LorbeerAbstract:Abstract The combwaxes of the honeybee species Apis mellifera, Apis cerana, Apis dorsata, Apis laboriosa, Apis florea and Apis andreniformis have been examined by High-Temperature Gas chromatography. Combwax consists of a complex mixture of homologous neutral lipids. These compounds containing up to 64 carbons were chromatographed intact on a 10 m×0.2 mm High-Temperature stable SOP-50-PFD (50%-diphenyl/50%-1H,1H,2H,2H-perfluorodecylmethylpolysiloxane)-coated Duran glass capillary column. The use of this stationary phase results in lower retention values and, at last, in lower thermal stress of the analytes. In order to minimize the discrimination effect due to adsorption and/or degradation, a two-step derivatization was performed resulting in the formation of tert.-butyldimethylsilyl esters of the long chain fatty acids and trimethylsilyl ethers of complex hydroxyesters, respectively. The derivatization procedure was optimized using a modification of the extended Donike test. In addition this test allows the quantification of the thermal stability of the derivatives performed. The derivatization procedure was applied for combwax analysis. More than 80 compounds were separated and their peak areas semiquantitatively exploited.
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Identification of cyclopropene triacylglycerols by High-Temperature Gas chromatography and High-Temperature Gas chromatography–negative chemical ionization mass spectrometry
Journal of Microcolumn Separations, 1999Co-Authors: Reiner Aichholz, Volker Spitzer, Eberhard LorbeerAbstract:The seed oil of Choriosa speciosa, which is known to be rich in cyclopropene triacylglycerols, has been investigated by High-Temperature Gas chromatography using glass capillary columns coated with the stationary phase SOP-50 (50% diphenyl–50% dimethylpolysiloxane, methoxy terminated). Cyclopropene rings were characterized after a mild catalyzed hydrogenation procedure. The partial π-character of the resulting cyclopropane ring supports the separation of individual triacylglycerol species on the polarizable stationary phase. Characterization of the separated compounds was performed by negative chemical ionization–mass spectrometry with ammonia as reagent Gas. ©1999 John Wiley & Sons, Inc. J Micro Sep 11: 223–229, 1999
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Analysis of cyanolipids and triacylglycerols from sapindaceae seed oils with High-Temperature Gas chromatography and High-Temperature Gas chromatography-chemical ionization mass spectrometry
Journal of Chromatography A, 1997Co-Authors: Reiner Aichholz, Volker Spitzer, Eberhard LorbeerAbstract:Abstract The seed oils of three Sapindaceae species have been examined by High-Temperature Gas chromatography using glass capillary columns coated with the stationary phases SOP-50 (50% diphenyl-50% dimethylpolysiloxane, methoxy-terminated) and OV-225-OH (25% phenylmethyl-25% cyanopropylmethylpolysiloxane, hydroxy-terminated), respectively. The cyanolipid and triacylglycerol fraction could be identified by a combination of High-Temperature Gas chromatography with a flame ionization and a nitrogen-phosphorus detector and Gas chromatography-mass spectrometry in positive and negative chemical ionization mode using NH3 and CH4/N2O as reagent Gases. The OV-225-OH phase showed better separation properties than the SOP-50 phase and up to 34 peaks could be separated. The analysis of the fatty acids in the seed oil of Allophylus edulis as their methyl esters by High-resolution GC and GC-MS are presented for the first time.
Volker Spitzer - One of the best experts on this subject based on the ideXlab platform.
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Identification of cyclopropene triacylglycerols by High-Temperature Gas chromatography and High-Temperature Gas chromatography–negative chemical ionization mass spectrometry
Journal of Microcolumn Separations, 1999Co-Authors: Reiner Aichholz, Volker Spitzer, Eberhard LorbeerAbstract:The seed oil of Choriosa speciosa, which is known to be rich in cyclopropene triacylglycerols, has been investigated by High-Temperature Gas chromatography using glass capillary columns coated with the stationary phase SOP-50 (50% diphenyl–50% dimethylpolysiloxane, methoxy terminated). Cyclopropene rings were characterized after a mild catalyzed hydrogenation procedure. The partial π-character of the resulting cyclopropane ring supports the separation of individual triacylglycerol species on the polarizable stationary phase. Characterization of the separated compounds was performed by negative chemical ionization–mass spectrometry with ammonia as reagent Gas. ©1999 John Wiley & Sons, Inc. J Micro Sep 11: 223–229, 1999
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Analysis of cyanolipids and triacylglycerols from sapindaceae seed oils with High-Temperature Gas chromatography and High-Temperature Gas chromatography-chemical ionization mass spectrometry
Journal of Chromatography A, 1997Co-Authors: Reiner Aichholz, Volker Spitzer, Eberhard LorbeerAbstract:Abstract The seed oils of three Sapindaceae species have been examined by High-Temperature Gas chromatography using glass capillary columns coated with the stationary phases SOP-50 (50% diphenyl-50% dimethylpolysiloxane, methoxy-terminated) and OV-225-OH (25% phenylmethyl-25% cyanopropylmethylpolysiloxane, hydroxy-terminated), respectively. The cyanolipid and triacylglycerol fraction could be identified by a combination of High-Temperature Gas chromatography with a flame ionization and a nitrogen-phosphorus detector and Gas chromatography-mass spectrometry in positive and negative chemical ionization mode using NH3 and CH4/N2O as reagent Gases. The OV-225-OH phase showed better separation properties than the SOP-50 phase and up to 34 peaks could be separated. The analysis of the fatty acids in the seed oil of Allophylus edulis as their methyl esters by High-resolution GC and GC-MS are presented for the first time.
T. Chiang - One of the best experts on this subject based on the ideXlab platform.
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High-Temperature Gas stream cleanup test facility
1995Co-Authors: J. Ontko, T. ChiangAbstract:The High-Temperature Gas stream cleanup facility at the Morgantown Energy Technology Center will provide a versatile platform for testing novel hot Gas cleanup filtration concepts. The facility will be available for joint ventures with CRADA partners.
Ta-kuan Chiang - One of the best experts on this subject based on the ideXlab platform.
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High-Temperature Gas-Stream Cleanup Test Facility
1996Co-Authors: D. Straub, Ta-kuan ChiangAbstract:In support of METC`s hot-Gas filter development program, the High- Temperature, Gas-stream cleanup test facility was designed to: investigate conventional and novel approaches to High-Temperature filtration; conduct detailed parametric studies that characterize particulate control devices under well-controlled conditions; and screen new materials for other High-Temperature applications, such as heat exchanger tubes. This new facility utilizes a natural Gas-fueled combustor to produce High-Temperature process Gas, and a screw feeder to inject ash, or other fine media, into the Gas stream. The vessel that surrounds the particulate control devices has an inside diameter of roughly 0.20 meters (8 inches) and is about 3 meters (10 feet) long. Three commercial-size filter elements can be tested simultaneously, and the facility is capable of operating over a wide range of conditions. Operating Temperatures can vary from 540 to 870{degrees}C (1,000 to 1,600 {degrees}F), and the operating pressure can vary from 0 to 400 kPa (0 to 60 psig).