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Sample records for characterization project headspace

  1. Tank Vapor Characterization Project: Headspace vapor characterization of Hanford Tank 241-TY-102: Results from samples collected on 04/12/96

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Pool, K.H.; Thomas, B.L. [and others

    1997-01-01

    This report describes the analytical results of vapor samples taken from the headspace of the waste storage tank 241-TY-102 (Tank TY-102) at the Hanford Site in Washington State. The results described in this report were obtained to`characterize the vapors present in the tank headspace and to support safety evaluations and tank farm operations. The results include air concentrations of selected inorganic and organic analytes, and grouped compounds from samples obtained by Westinghouse Hanford Company (WHC) and provided for analysis to Pacific Northwest National Laboratory (PNNL). Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Analyte concentrations were based on analytical results and, where appropriate, sample volumes provided by WHC. A summary of the inorganic analytes, permanent gases, and total non-methane organic compounds is listed in Table S.1. The three highest concentration analytes detected in SUMMA{trademark} canister and triple sorbent trap samples are also listed in Table S.1. Detailed descriptions of the analytical results appear in the appendices.

  2. Tank 241-B-103 headspace gas and vapor characterization: Results for homogeneity samples collected on October 16, 1996. Tank vapor characterization project

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    Olsen, K.B.; Pool, K.H.; Evans, J.C. [and others

    1997-06-01

    This report presents the results of analyses of samples taken from the headspace of waste storage tank 241-B-103 (Tank B-103) at the Hanford Site in Washington State. Samples were collected to determine the homogeneity of selected inorganic and organic headspace constituents. Two risers (Riser 2 and Riser 7) were sampled at three different elevations (Bottom, Middle, and Top) within the tank. Tank headspace samples were collected by SGN Eurisys Service Corporation (SESC) and were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL.

  3. Tank vapor characterization project - Tank 241-U-112 headspace gas and vapor characterization: Results for homogeneity samples collected on December 6, 1996

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    Sklarew, D.S.; Pool, K.H.; Evans, J.C.; Hayes, J.C. [and others

    1997-09-01

    This report presents the results of analyses of samples taken from the headspace of waste storage tank 241-U-112 (Tank U-112) at the Hanford Site in Washington State. Samples were collected to determine the homogeneity of selected inorganic and organic headspace constitutents. Two risers (Riser 3 and Riser 6) were sampled at three different elevations (Bottom, Middle, and Top) within the tank. Tank headspace samples were collected by SGN Eurisys Service Corporation (SESC) and were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Ammonia was determined to be above the immediate notification limit specified by the sampling and analysis plan.

  4. Tank vapor characterization project - Tank 241-TY-103 headspace gas and vapor characterization: Results for homogeneity samples collected on November 22, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, K.B.; Pool, K.H.; Evans, J.C.; Hayes, J.C. [and others

    1997-07-01

    This report presents the results of analyses of samples taken from the headspace of waste storage tank 241-TY-103 (Tank TY-103) at the Hanford Site in Washington State. Samples were collected to determine the homogeneity of selected inorganic and organic headspace constituents. Two risers (Riser 8 and Riser 18) were sampled at three different elevations (Top, Middle, and Bottom) within the tank. Tank headspace samples were collected by SGN Eurisys Service Corporation (SESC) and were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. No analytes were determined to be above immediate notification limits specified by the sampling and analysis plan (SAP).

  5. Tank Vapor Characterization Project: Tank 241-S-102 fourth temporal study: Headspace gas and vapor characterization results from samples collected on December 19, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Pool, K.H.; Evans, J.C.; Olsen, K.B.; Hayes, J.C. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-S-102 (Tank S-102) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurisys Service Corporation (SESC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by SESC. Ammonia was determined to be above the immediate notification limit of 150 ppm as specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank S-102 headspace, determined to be present at approximately 2.410% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <2.973% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <2.973% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  6. Tank 241-BX-104 fourth temporal study: Headspace gas and vapor characterization results from samples collected on April 7, 1997. Tank vapor characterization project

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    Mitroshkov, A.V.; Hayes, J.C.; Evans, J.C. [and others

    1997-09-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BX-04 (Tank BX-104) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurisys Service Corporation (SESC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by SESC. Ammonia was determined to be above the immediate notification limit specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank BX-104 headspace, determined to be present at approximately 0.208% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <0.536% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  7. Tank 241-BY-108 fifth temporal study: Headspace gas and vapor characterization results from samples collected on January 30, 1997. Tank vapor characterization project

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    Evans, J.C.; Pool, K.H.; Olsen, K.B. [and others

    1997-09-01

    This report presents the results from analyses of samples taken from tile headspace of waste storage tank 241-B-108 (Tank BY - 108) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurisys Services Corporation (SESC) and analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by SESC. Ammonia was determined to be above the immediate notification limit of 150 ppm specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank BY-108 headspace, determined to be present at approximately 0.888% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <1.979% of tile LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  8. Tank vapor characterization project: Tank 241-S-102 temporal study headspace gas and vapor characterization results from samples collected on September 19, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.; Sklarew, D.S. [and others

    1997-08-01

    This report presents the results from analysis of samples taken from the headspace of waste storage tank 241-S-102 (Tank S-102) at the Hanford Site in Washington State. Tank headspace samples collected by Westinghouse Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by WHC. Ammonia was determined to be above the immediate notification limit of 150 ppm as specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank S-102 headspace, determined to be present at approximately 2.948% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <3.659% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Tables S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  9. Tank vapor characterization project: Tank 241-BX-104 fifth temporal study: Headspace gas and vapor characterization results from samples collected on June 10, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, J.C.; Pool, K.H.; Evans, J.C.; Olsen, K.B. [and others

    1997-07-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BX-104 (Tank BX-104) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurisys Service Corporation (SESC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by SESC. Ammonia was determined to be above the immediate notification limit specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank BX-104 headspace, determined to be present at approximately 0.270% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <0.675% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  10. Tank 241-BY-108 fourth temporal study: Headspace gas and vapor characterization results from samples collected on November 14, 1997. Tank vapor characterization project

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Pool, K.H.; Olsen, K.B. [and others

    1997-07-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BY-108 (Tank BY-108) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurisys Service Corporation (SESC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected nonradioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by SESC. Ammonia was determined to be above the immediate notification limit of 150 ppm specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank BY-108 headspace, determined to be present at approximately 1.390% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <2.830% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  11. Tank Vapor Characterization Project: Tank 241-BX-103 headspace gas and vapor characterization results from samples collected on August 1, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.; Sklarew, D.S.; Edwards, J.A. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from headspace of waste storage tank 241-BX-103 (Tank BX-103) at the Hanford Site in Washington State. Tank headspace samples collected by Westinghouse Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by WHC. No analytes were determined to be above the immediate notification limits specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank BX-103 headspace, determined to be present at approximately 0.385% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <0.633% if the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  12. Tank 241-BX-104 third temporal study: Headspace gas and vapor characterization results from samples collected on February 6, 1997. Tank vapor characterization project

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Pool, K.H.; Hayes, J.C. [and others

    1997-09-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BX-104 (Tank BX-104) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurisys Service Corporation (SESC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by SESC. Ammonia was determined to be above the immediate notification limit specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank BX-104 headspace, determined to be present at approximately 0.178 % of its lower flammability limit (LFL). Total headspace flammability was estimated to be <0.458% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  13. Tank Vapor Characterization Project: Tank 241-BX-104 headspace gas and vapor characterization results from samples collected on August 22, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.; Olsen, K.B.; Julya, J.L. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BX-104 (Tank BX-104) at the Hanford Site in Washington State. Tank headspace samples collected by Westinghouse Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by WHC. Ammonia was determined to be above the immediate notification limit specified by the sampling and analyses plan (SAP). Total non-methane organic compounds was the principal flammable constituent of the Tank BX-104 headspace, determined to be present at approximately 0.310% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <0.784% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  14. Tank Vapor Characterization Project: Tank 241-C-107 fourth temporal study: Headspace gas and vapor characterization results from samples collected on December 17, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Pool, K.H.; Evans, J.C.; Olsen, K.B.; Hayes, J.C. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-C-107 (Tank C-107) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurisys Service Corporation (SESC) and were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by SESC. No analytes were determined to be above the immediate notification limits specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank C-107 headspace, determined to be present at approximately 2.825% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <2.935% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  15. Tank Vapor Characterization Project: Tank 241-BX-104 second temporal study headspace gas and vapor characterization results from samples collected on December 12, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Pool, K.H.; Evans, J.C.; Hayes, J.C.; Olsen, K.B. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BX-104 (Tank BX-104) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurisys Service Corporation (SESC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample provided by SESC. Ammonia was determined to be above the immediate notification limit specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank BX-104 headspace, determined to be present at approximately 0.248% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <0.645% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  16. Tank 241-S-102 fifth temporal study: Headspace gas and vapor characterization results from samples collected on February 11, 1997. Tank vapor characterization project

    Energy Technology Data Exchange (ETDEWEB)

    Mitroshkov, A.V.; Evans, J.C.; Hayes, J.C. [and others

    1997-09-01

    This report presents tile results from analyses of samples taken from the headspace of waste storage tank 241-S-102 (Tank S-102) at the Hanford Site in Washington State. Tank headspace samples collected by SGN Eurlsys Service Corporation (SESC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by tile Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based oil measured sample volumes provided by SESC. Ammonia was determined to be above tile immediate notification limit of 150 ppm as specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank S-102 headspace, determined to be present at approximately 1.150% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <1.624% of the LFL, Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of tile analytical results are provided in Section 3.0.

  17. Tank Vapor Characterization Project: Tank 241-BX-102 headspace gas and vapor characterization results from samples collected on July 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Pool, K.H.; Evans, J.C.; Thomas, B.L.; Olsen, K.B. Edwards, J.A. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BX-102 (Tank BX-102) at the Hanford Site in Washington State. Tank headspace samples collected by Westinghouse Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured volumes provided by WHC. No analytes were determined to be above the immediate notification limits specified by the sampling and and analysis plan. Ammonia and TNMOCs were the principal flammable constituents of the Tank BX-102 headspace, each determined to be present at approximately 0.002% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <0.107% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  18. Tank Vapor Characterization Project: Tank 241-BX-111 headspace gas and vapor characterization results from samples collected on August 27, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Pool, K.H.; Evans, J.C.; Thomas, B.L.; Sklarew, D.S. Edwards, J.A. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BX-111 (Tank BX-111) at the Hanford Site in Washington State. Tank headspace samples collected by Westinghouse Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by WHC. No analytes were determined to be above the immediate notification limits specified by the sampling and analysis plan (SAP). Ammonia was the principal flammable constituent of the Tank BX-111 headspace, determined to be present at approximately 0.042 of its lower flammability limit (LFL). Total headspace flammability was estimated to be <0.157% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  19. Tank Vapor Characterization Project: Tank 241-C-107 temporal study headspace gas and vapor characterization results from samples collected on September 5, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Pool, K.H.; Evans, J.C.; Thomas, B.L.; Edwards, J.A.; Silvers, K.L. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-C-107 at the Hanford Site in Washington State. Tank headspace samples collected by Westinghouse Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by WHC. No analytes were determined to be above the immediate notification limits specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank C-107 headspace, determined to be present at approximately 1.405% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <1.519% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  20. Tank vapor characterization project: Tank 241-BY-101 headspace gas and vapor characterization results from samples collected on August 29, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.; Olsen, K.B. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BY-101 (Tank BY-101) at the Hanford Site in Washington State. Tank headspace samples collected by Westinghouse Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by WHC. No analytes were determined to be above the immediate notification limits specified by the sampling and analysis plan (SAP). Total non-methane organic compounds (TNMOCs) were the principal flammable constituent of the Tank By-101 headspace, determined to be present at approximately 0.136% of the LFL. Averaged measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  1. Tank Vapor Characterization Project: Tank 241-BY-108 temporal study headspace gas and vapor characterization results from samples collected on September 10, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.C.; Pool, K.H.; Thomas, B.L.; Sklarew, D.S. [and others

    1997-08-01

    This report presents the results from analyses of samples taken from the headspace of waste storage tank 241-BY-108 (Tank BY-108) at the Hanford Company (WHC) were analyzed by Pacific Northwest National Laboratory (PNNL) to determine headspace concentrations of selected non-radioactive analytes. Analyses were performed by the Vapor Analytical Laboratory (VAL) at PNNL. Vapor concentrations from sorbent trap samples are based on measured sample volumes provided by WHC. Ammonia was determined to be above the immediate notification limit of 150 ppm specified by the sampling and analysis plan (SAP). Hydrogen was the principal flammable constituent of the Tank BY-108 headspace, determined to be present at approximately 1.463% of its lower flammability limit (LFL). Total headspace flammability was estimated to be <2.940% of the LFL. Average measured concentrations of targeted gases, inorganic vapors, and selected organic vapors are provided in Table S.1. A summary of experimental methods, including sampling methodology, analytical procedures, and quality assurance and control methods are presented in Section 2.0. Detailed descriptions of the analytical results are provided in Section 3.0.

  2. Fast characterization of cheeses by dynamic headspace-mass spectrometry.

    Science.gov (United States)

    Pérès, Christophe; Denoyer, Christian; Tournayre, Pascal; Berdagué, Jean-Louis

    2002-03-15

    This study describes a rapid method to characterize cheeses by analysis of their volatile fraction using dynamic headspace-mass spectrometry. Major factors governing the extraction and concentration of the volatile components were first studied. These components were extracted from the headspace of the cheeses in a stream of helium and concentrated on a Tenax TA trap. They were then desorbed by heating and injected directly into the source of a mass spectrometer via a short deactivated silica transfer line. The mass spectra of the mixture of volatile components were considered as fingerprints of the analyzed substances. Forward stepwise factorial discriminant analysis afforded a limited number of characteristic mass fragments that allowed a good classification of the batches of cheeses studied.

  3. Tank 241-C-106 headspace gas and vapor characterization results for samples collected in February 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hackaby, J.L. [Pacific Northwest Lab., Washington, DC (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-26

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  4. Tank 241-U-103 headspace gas and vapor characterization results for samples collected in February 1995

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Richland, WA (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-27

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories.

  5. Tank 241-U-111 headspace gas and vapor characterization results for samples collected in February 1995

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Richland, WA (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories.

  6. Tank 241-SX-106 headspace gas and vapor characterization results for samples collected in March 1995

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Richland, WA (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories.

  7. Tank 241-S-102 headspace gas and vapor characterization results for samples collected in March 1995

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Richland, WA (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-26

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  8. Tank 241-U-107 headspace gas and vapor characterization results for samples collected in February 1995

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Richland, WA (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories.

  9. Tank 241-TY-104 headspace gas and vapor characterization results for samples collected in April 1995

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Richland, WA (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories.

  10. Tank 241-C-111 headspace gas and vapor characterization results for samples collected in August 1993 and September 1994

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Richland, WA (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories.

  11. Tank 241-BY-107 headspace gas and vapor characterization results for samples collected in March 1994 and October 1994

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Richland, WA (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories.

  12. Characterization of the most odor-active compounds of Iberian ham headspace.

    Science.gov (United States)

    Carrapiso, Ana I; Ventanas, Jesús; García, Carmen

    2002-03-27

    Gas chromatography-olfactometry (GC-O) based on detection frequency (DF) was used to characterize the most odor-active compounds from the headspace of Iberian ham. Twenty-eight odorants were identified by GC-O on two capillary columns, including aldehydes (11), sulfur-containing compounds (7), ketones (5), nitrogen-containing compounds (2), esters (2), and an alcohol. Among them, the highest odor potencies (DF values) were found for 2-methyl-3-furanthiol, 2-heptanone, 3-methylbutanal, methanethiol, hexanal, hydrogen sulfide, 1-penten-3-one, 2-methylpropanal, ethyl 2-methylbutyrate, and (E)-2-hexenal. Nine of the 28 most odor-active compounds were identified for the first time as aroma components of dry-cured ham, including hydrogen sulfide, 1-penten-3-one, (Z)-3-hexenal, 1-octen-3-one, and the meaty-smelling compounds 2-methyl-3-furanthiol, 2-furfurylthiol, 3-mercapto-2-pentanone, 2-acetyl-1-pyrroline, and 2-propionyl-1-pyrroline.

  13. Tank 241-BY-105 Headspace Gas and Vapor Characterization Results for Samples Collected in May 1994 and July 1994. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L. [Pacific Northwest Lab., Washington, DC (United States); Bratzel, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-09-01

    Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories

  14. Characterization of Brazilian green propolis throughout the seasons by headspace GC/MS and ESI-MS.

    Science.gov (United States)

    Nunes, Cleiton A; Guerreiro, Mário C

    2012-01-30

    A screening of the chemical composition of eight commercial classes of raw Brazilian green propolis throughout the seasons was carried out. A multivariate exploratory analysis of chemical composition obtained by gas chromatography associated with mass spectrometry with headspace extraction (HS-GC/MS), and by mass spectrometry with electrospray ionization (ESI-MS) was carried out using principal component analysis (PCA). Differences in the volatile and polyphenolic profiles of propolis samples were verified during the seasons. Within each season, the high quality commercial classes of propolis presented similar characteristics, while the low quality classes presented distinct compositions. In spring and summer, propolis of the trimming class, commonly considered of low quality by beekeepers, presented a composition similar to the superior quality propolis. Seasonality influences the chemical composition of the commercial classes of raw Brazilian green propolis. Headspace-GC/MS and ESI-MS assisted by PCA are effective to characterize volatile and non-volatile compounds of the propolis samples, and to correlate it to the seasons. Copyright © 2011 Society of Chemical Industry.

  15. Characterization of volatiles from cultured dairy spreads during storage by dynamic headspace GC/MS

    DEFF Research Database (Denmark)

    Lund, Pia; Hølmer, Gunhild Kofoed

    2001-01-01

    The effect of storage time and storage temperature on the formation of volatile compounds in dairy spreads was investigated. Dairy spreads were stored for 10 weeks at -18, 5 and 20 degreesC, respectively, and analyzed after 0, 38, 54 and 67 days of storage. By means of a dynamic headspace GC....../MS method using Tenax traps the dairy spreads were analyzed for volatile aromatic compounds. 61 components were identified and their relative content was followed during the storage period. Among these were four alcohols, 17 aldehydes, four esters, ten alkanes, 11 ketones and six lactones. A general...... increase in the concentration of most of the volatile compounds during storage was found. The content of volatile compounds in dairy spreads stored at -18 OC was nearly constant or showed a rather low increase in the content during the storage period. Storage at higher temperatures (5 and 20 degrees...

  16. Characterization of volatile compounds of Daucus crinitus Desf. Headspace Solid Phase Microextraction as alternative technique to Hydrodistillation

    Directory of Open Access Journals (Sweden)

    Tabti Boufeldja

    2010-09-01

    Full Text Available Abstract Background Traditionally, the essential oil of aromatic herbs is obtained using hydrodistillation (HD. Because the emitted volatile fraction plays a fundamental role in a plant's life, various novel techniques have been developed for its extraction from plants. Among these, headspace solid phase microextraction (HS-SPME can be used to obtain a rapid fingerprint of a plant's headspace. Daucus crinitus Desf. is a wild plant that grows along the west coast of Algeria. Only a single study has dealt with the chemical composition of the aerial part oils of Algerian D. crinitus, in which isochavicol isobutyrate (39.0%, octyl acetate (12.3%, and β-caryophyllene (5.4% were identified. Using GC-RI and GC-MS analysis, the essential oils and the volatiles extracted from separated organs of D. crinitus Desf. were studied using HS-SPME. Results GC-RI and GC-MS analysis identified 72 and 79 components in oils extracted using HD and in the volatile fractions extracted using SPME, respectively. Two types of essential oils were produced by the plant: the root oils had aliphatic compounds as the main component (87.0%-90.1%, and the aerial part oils had phenylpropanoids as the main component (43.1%-88.6%. HS-SPME analysis showed a more precise distribution of compounds in the organs studied: oxygenated aliphatic compounds were well represented in the roots (44.3%-84.0%, hydrocarbon aliphatic compounds were in the leaves and stems (22.2%-87.9%, and phenylpropanoids were in the flowers and umbels (47.9%-64.2%. Moreover, HS-SPME allowed the occurrence of isochavicol (29.6 - 34.7% as main component in D. crinitus leaves, but it was not detected in the oils, probably because of its solubility in water. Conclusions This study demonstrates that HD and HS-SPME modes could be complimentary extraction techniques in order to obtain the complete characterization of plant volatiles.

  17. Dynamic headspace gas chromatography/mass spectrometry characterization of volatiles produced in fish oil enriched mayonnaise during storage.

    Science.gov (United States)

    Hartvigsen, K; Lund, P; Hansen, L F; Holmer, G

    2000-10-01

    Protection against lipid oxidation and formation of unpleasant fishy and rancid off-flavors in oil-in-water food emulsions, such as fish oil enriched mayonnaise, is difficult to achieve. Volatile profiles from stored mayonnaises with different oil phase compositions were collected using a developed dynamic headspace sampling technique, in which interfering acetic acid was removed in situ with potassium hydroxide, and subsequently 148 volatiles were characterized and monitored by gas chromatography/mass spectrometry. Multivariate statistics showed correlation between the concentration of 62 volatiles and the fish oil and storage parameters, indicating the formation of lipid oxidation products, which impose fishy off-flavors. Further verification was obtained by gas chromatography/olfactometry, by which, among 78 odors, cis-4-heptenal and trans,cis-2,4-heptadienal were detected as distinct fishy notes. In total, 27 volatiles, including 1-penten-3-one, cis-2-penten-1-ol, cis-3-hexenal, cis-4-heptenal, 1-octen-3-one, 1,cis-5-octadien-3-one, 1-octen-3-ol, trans,cis-2, 4-heptadienal, and trans,cis-2,6-nonadienal, were suggested to contribute to the developed unpleasant fishy and rancid off-flavors.

  18. Use of headspace mulberry paper bag micro solid phase extraction for characterization of volatile aromas of essential oils from Bulgarian rose and Provence lavender.

    Science.gov (United States)

    Won, Mi-Mi; Cha, Eun-Ju; Yoon, Ok-Kyung; Kim, Nam-Sun; Kim, Kun; Lee, Dong-Sun

    2009-01-05

    In this study, a new sampling method called headspace mulberry paper bag micro solid phase extraction (HS-MPB-mu-SPE) combined to gas chromatography-mass spectrometry has been applied for the analysis of volatile aromas of liquid essential oils from Bulgarian rose and Provence lavender. The technique uses an adsorbent (Tenax TA) contained in a mulberry paper bag, minimal amount of organic solvent. Linearities for the six-points calibration curves were excellent. LOD values were in the rage from 0.38 ng mL(-1) to 0.77 ng mL(-1). Overall, precision and recovery were generally good. Phenethyl alcohol and citronellol were the main components in the essential oil from Bulgarian rose. Linalyl acetate and linalool were the most abundant components in the essential oils from true lavender or lavandin. Additionally, the relative extraction efficiencies of proposed method have been compared with HS-SPME. The overall extraction efficiency was evaluated by the relative concentration factors (CF) of the several characteristic components. CF values by HS-MPB-mu-SPE were lower than those by headspace solid phase microextraction (HS-SPME). The HS-MPB-mu-SPE method is very simple to use, inexpensive, rapid, requires small sample amounts and solvent consumption. In addition, this method allowed combining of extraction, enrichment, and clean-up in a single step. HS-MPB-mu-SPE and GC/MS is a promising technique for the characterization of volatile aroma compounds from liquid essential oils.

  19. Headspace solid-phase microextraction for characterization of fragrances of lemon verbena (Aloysia triphylla) by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Kim, Nam-Sun; Lee, Dong-Sun

    2004-01-01

    Natural fragrances from lemon verbena (Aloysia triphylla) were studied by headspace solid phase microextraction (HS-SPME) techniques followed by gas chromatography-mass spectrometry (GC-MS), with six different fibre coatings being tested to evaluate the extraction efficiencies of several selected compounds. A total of 14 compounds were identified in the fragrances of lemon verbena. Geranial and neral were detected as major components and alpha-pinene, beta-pinene, beta-caryophyllene, and curcumene as minor components. Enantiomeric analysis of chiral compounds from lemon verbena was carried out on a chiral column. alpha-Pinene, limonene, and camphor in the fragrances emitted from lemon verbena were found in the (+), (-), and (-) forms, respectively.

  20. Characterization of the volatile organic compounds present in the headspace of decomposing animal remains, and compared with human remains.

    Science.gov (United States)

    Cablk, Mary E; Szelagowski, Erin E; Sagebiel, John C

    2012-07-10

    Human Remains Detection (HRD) dogs can be a useful tool to locate buried human remains because they rely on olfactory rather than visual cues. Trained specifically to locate deceased humans, it is widely believed that HRD dogs can differentiate animal remains from human remains. This study analyzed the volatile organic compounds (VOCs) present in the headspace above partially decomposed animal tissue samples and directly compared them with results published from human tissues using established solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) methods. Volatile organic compounds present in the headspace of four different animal tissue samples (bone, muscle, fat and skin) from each of cow, pig and chicken were identified and compared to published results from human samples. Although there were compounds common to both animal and human remains, the VOC signatures of each of the animal remains differed from those of humans. Of particular interest was the difference between pigs and humans, because in some countries HRD dogs are trained on pig remains rather than human remains. Pig VOC signatures were not found to be a subset of human; in addition to sharing only seven of thirty human-specific compounds, an additional nine unique VOCs were recorded from pig samples which were not present in human samples. The VOC signatures from chicken and human samples were most similar sharing the most compounds of the animals studied. Identifying VOCs that are unique to humans may be useful to develop human-specific training aids for HRD canines, and may eventually lead to an instrument that can detect clandestine human burial sites. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  1. Aerosol characterization during project POLINAT

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, D.E.; Hopkins, A.R.; Paladino, J.D.; Whitefield, P.D. [Missouri Univ., Rolla, MO (United States). Cloud and Aerosol Sciences Lab.; Lilenfeld, H.V. [McDonnell Douglas Aerospace-East, St. Louis, MO (United States)

    1997-12-31

    The objectives of the aerosol/particulate characterization measurements of project POLINAT (POLlution from aircraft emissions In the North ATlantic flight corridor) are: to search for aerosol/particulate signatures of air traffic emissions in the region of the North Atlantic Flight Corridor; to search for the aerosol/particulate component of large scale enhancement (`corridor effects`) of air traffic related species in the North Atlantic region; to determine the effective emission indices for the aerosol/particulate component of engine exhaust in both the near and far field of aircraft exhaust plumes; to measure the dispersion and transformation of the aerosol/particulate component of aircraft emissions as a function of ambient condition; to characterize background levels of aerosol/particulate concentrations in the North Atlantic Region; and to determine effective emission indices for engine exhaust particulates for regimes beyond the jet phase of plume expansion. (author) 10 refs.

  2. Characterization of volatile compounds of Daucus crinitus Desf. Headspace Solid Phase Microextraction as alternative technique to Hydrodistillation

    OpenAIRE

    Tabti Boufeldja; Allali Houcine; Desjobert Jean-Marie; Djabou Nassim; El Amine Dib Mohammed; Muselli Alain; Costa Jean

    2010-01-01

    Background : Traditionally, the essential oil of aromatic herbs is obtained using hydrodistillation (HD). Because the emitted volatile fraction plays a fundamental role in a plant's life, various novel techniques have been developed for its extraction from plants. Among these, headspace solid phase microextraction (HS-SPME) can be used to obtain a rapid fingerprint of a plant's headspace. Daucus crinitus Desf. is a wild plant that grows along the west coast of Algeria. Only a single study ...

  3. Characterize Human Forward Contamination Project

    Science.gov (United States)

    Rucker, Michelle

    2015-01-01

    Let's face it: wherever we go, we will inevitably carry along the little critters that live in and on us. Conventional wisdom has long held that it's unlikely those critters could survive the space environment, but in 2007 microscopic animals called Tardigrades survived exposure to space and in 2008 Cyanobacteria lived for 548 days outside the International Space Station (ISS). But what about the organisms we might reasonably expect a crewed spacecraft to leak or vent? Do we even know what they are? How long might our tiny hitch-hikers survive in close proximity to a warm spacecraft that periodically leaks/vents water or oxygen-and how might they mutate with long-duration exposure? Unlike the Mars rovers that we cleaned once and sent on their way, crew members will provide a constantly regenerating contaminant source. Are we prepared to certify that we can meet forward contamination protocols as we search for life at new destinations? This project has four technical objectives: 1. TEST: Develop a test plan to leverage existing equipment (i.e. ISS) to characterize the kinds of organisms we can reasonably expect pressurized, crewed volumes to vent or leak overboard; as part of testing, we'll need to develop an Extravehicular Activity (EVA)-compatible tool that can withstand the pressure and temperature extremes of space, as well as collect, separate, and store multiple samples; 2. ANALYSIS: Develop an analysis plan to study those organisms in relevant destination environments, including spacecraft-induced conditions; 3. MODEL: Develop a modeling plan to model organism transport mechanisms in relevant destination environments; 4. SHARE: Develop a plan to disseminate findings and integrate recommendations into exploration requirements & ops. In short, we propose a system engineering approach to roadmap the necessary experiments, analysis, and modeling up front--rather than try to knit together disparate chunks of data into a sensible conclusion after the fact.

  4. Projective Hulls and Characterizations of Meromorphic Functions

    CERN Document Server

    Anderson, J T; Levenberg, N; Ransford, T J

    2011-01-01

    We give conditions characterizing holomorphic and meromorphic functions in the unit disk of the complex plane in terms of certain weak forms of the maximum principle. Our work is directly inspired by recent results of John Wermer, and by the theory of the projective hull of a compact subset of complex projective space developed by Reese Harvey and Blaine Lawson.

  5. Headspace Analysis of Ammonium Nitrate

    Science.gov (United States)

    2017-01-25

    Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/6110--17-9709 Headspace Analysis of Ammonium Nitrate January 25, 2017 Approved for public...TELEPHONE NUMBER (include area code) b. ABSTRACT c. THIS PAGE 18. NUMBER OF PAGES 17. LIMITATION OF ABSTRACT Headspace Analysis of Ammonium Nitrate G...isobutane reagent ion from analysis of ammonia desorbed from packed tungsten oxide sampling tube .................. 18 E-1 Executive Summary The

  6. Gypsy Field project in reservoir characterization

    Energy Technology Data Exchange (ETDEWEB)

    Castagna, John P.; Jr., O' Meara, Daniel J.

    2000-01-12

    The overall objective of this project was to use extensive Gypsy Field Laboratory and data as a focus for developing and testing reservoir characterization methods that are targeted at improved recovery of conventional oil. This report describes progress since project report DOE/BC/14970-7 and covers the period June 1997-September 1998 and represents one year of funding originally allocated for the year 1996. During the course of the work previously performed, high resolution geophysical and outcrop data revealed the importance of fractures at the Gypsy site. In addition, personnel changes and alternative funding (OCAST and oil company support of various kinds) allowed the authors to leverage DOE contributions and focus more on geophysical characterization.

  7. Performance Demonstration Program Plan for Analysis of Simulated Headspace Gases

    Energy Technology Data Exchange (ETDEWEB)

    Carlsbad Field Office

    2007-11-13

    The Performance Demonstration Program (PDP) for headspace gases distributes blind audit samples in a gas matrix for analysis of volatile organic compounds (VOCs). Participating measurement facilities (i.e., fixed laboratories, mobile analysis systems, and on-line analytical systems) are located across the United States. Each sample distribution is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed for transuranic (TRU) waste characterization. The primary documents governing the conduct of the PDP are the Quality Assurance Program Document (QAPD) (DOE/CBFO-94-1012) and the Waste Isolation Pilot Plant (WIPP) Waste Analysis Plan (WAP) contained in the Hazardous Waste Facility Permit (NM4890139088-TSDF) issued by the New Mexico Environment Department (NMED). The WAP requires participation in the PDP; the PDP must comply with the QAPD and the WAP. This plan implements the general requirements of the QAPD and the applicable requirements of the WAP for the Headspace Gas (HSG) PDP. Participating measurement facilities analyze blind audit samples of simulated TRU waste package headspace gases according to the criteria set by this PDP Plan. Blind audit samples (hereafter referred to as PDP samples) are used as an independent means to assess each measurement facility’s compliance with the WAP quality assurance objectives (QAOs). To the extent possible, the concentrations of VOC analytes in the PDP samples encompass the range of concentrations anticipated in actual TRU waste package headspace gas samples. Analyses of headspace gases are required by the WIPP to demonstrate compliance with regulatory requirements. These analyses must be performed by measurement facilities that have demonstrated acceptable performance in this PDP. These analyses are referred to as WIPP analyses and the TRU waste package headspace gas samples on which they are performed are referred to as WIPP samples in this document

  8. Performance Demonstration Program Plan for Analysis of Simulated Headspace Gases

    Energy Technology Data Exchange (ETDEWEB)

    Carlsbad Field Office

    2007-11-19

    The Performance Demonstration Program (PDP) for headspace gases distributes blind audit samples in a gas matrix for analysis of volatile organic compounds (VOCs). Participating measurement facilities (i.e., fixed laboratories, mobile analysis systems, and on-line analytical systems) are located across the United States. Each sample distribution is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed for transuranic (TRU) waste characterization. The primary documents governing the conduct of the PDP are the Quality Assurance Program Document (QAPD) (DOE/CBFO-94-1012) and the Waste Isolation Pilot Plant (WIPP) Waste Analysis Plan (WAP) contained in the Hazardous Waste Facility Permit (NM4890139088-TSDF) issued by the New Mexico Environment Department (NMED). The WAP requires participation in the PDP; the PDP must comply with the QAPD and the WAP. This plan implements the general requirements of the QAPD and the applicable requirements of the WAP for the Headspace Gas (HSG) PDP. Participating measurement facilities analyze blind audit samples of simulated TRU waste package headspace gases according to the criteria set by this PDP Plan. Blind audit samples (hereafter referred to as PDP samples) are used as an independent means to assess each measurement facility’s compliance with the WAP quality assurance objectives (QAOs). To the extent possible, the concentrations of VOC analytes in the PDP samples encompass the range of concentrations anticipated in actual TRU waste package headspace gas samples. Analyses of headspace gases are required by the WIPP to demonstrate compliance with regulatory requirements. These analyses must be performed by measurement facilities that have demonstrated acceptable performance in this PDP. These analyses are referred to as WIPP analyses and the TRU waste package headspace gas samples on which they are performed are referred to as WIPP samples in this document

  9. Development of a portable mass spectrometer characterized by discontinuous sample gas introduction, a low-pressure dielectric barrier discharge ionization source, and a vacuumed headspace technique.

    Science.gov (United States)

    Kumano, Shun; Sugiyama, Masuyuki; Yamada, Masuyoshi; Nishimura, Kazushige; Hasegawa, Hideki; Morokuma, Hidetoshi; Inoue, Hiroyuki; Hashimoto, Yuichiro

    2013-05-21

    The present study has attempted to downscale a mass spectrometer in order to make it portable and enable onsite analysis with it. The development of a small mass spectrometer required the use of a compact pump whose displacement was small, decreasing the sensitivity of that spectrometer. To get high sensitivity with a small mass spectrometer, we have integrated novel techniques: a highly sensitive ionization source and efficient extraction of sample vapor. The low-pressure dielectric barrier discharge ionization (LP-DBDI) source made it possible to increase the conductance between the source and the mass analyzer, compared with ambient ionization sources, enhancing the efficiency of the ion transfer from the ionization source to the mass analyzer. We have also developed a vacuumed headspace method efficiently transporting the sample vapor to the ionization source. The sensitivity was further enhanced by also using a discontinuous sample gas introduction technique. A prototype portable mass spectrometer using those novel techniques was found to be sensitive enough to detect 0.1 ppm methamphetamine, 1 ppm amphetamine, 1 ppm 3,4-methylenedioxymethamphetamine, and 10 ppm cocaine in liquid.

  10. Headspace analysis of foams and fixatives

    Energy Technology Data Exchange (ETDEWEB)

    Harper, Kyle [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Truong, Thanh-Tam [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Magwood, Leroy [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Peters, Brent [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nicholson, James [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-27

    In the process of decontaminating and decommissioning (D&D) older nuclear facilities, special precautions must be taken with removable or airborne contamination. One possible strategy utilizes foams and fixatives to affix these loose contaminants. Many foams and fixatives are already commercially available, either generically or sold specifically for D&D. However, due to a lack of revelant testing in a radioactive environment, additional verification is needed to confirm that these products not only affix contamination to their surfaces, but also will function in a D&D environment. Several significant safety factors, including flammability and worker safety, can be analyzed through the process of headspace analysis, a technique that analyzes the off gas formed before or during the curing process of the foam/fixative, usually using gas chromatography-mass spectrometry (GC-MS). This process focuses on the volatile components of a chemical, which move freely between the solid/liquid form within the sample and the gaseous form in the area above the sample (the headspace). Between possibly hot conditions in a D&D situation and heat created in a foaming reaction, the volatility of many chemicals can change, and thus different gasses can be released at different times throughout the reaction. This project focused on analysis of volatile chemicals involved in the process of using foams and fixatives to identify any potential hazardous or flammable compounds.

  11. Orbital Debris Shape Characterization Project Abstract

    Science.gov (United States)

    Pease, Jessie

    2016-01-01

    I have been working on a project to further our understanding of orbital debris by helping create a new dataset previously too complex to be implemented in past orbital debris propagation models. I am doing this by creating documentation and 3D examples and illustrations of the shape categories. Earlier models assumed all orbital debris to be spherical aluminum fragments. My project will help expand our knowledge of shape populations to 6 categories: Straight Needle/Rod/Cylinder, Bent Needle/Rod/Cylinder, Flat Plate, Bent Plate, Nugget/Parallelepiped/Spheroid, and Flexible. The last category, Flexible, is still up for discussion and may be modified. These categories will be used to characterize fragments in the DebriSat experiment.

  12. Characterization of sulfur compounds in whisky by full evaporation dynamic headspace and selectable one-dimensional/two-dimensional retention time locked gas chromatography-mass spectrometry with simultaneous element-specific detection.

    Science.gov (United States)

    Ochiai, Nobuo; Sasamoto, Kikuo; MacNamara, Kevin

    2012-12-28

    A method is described for characterization of sulfur compounds in unaged and aged whisky. The method is based on full evaporation dynamic headspace (FEDHS) of 100 μL of whisky samples followed by selectable one-dimensional ((1)D) or two-dimensional ((2)D) retention-time-locked (RTL) gas chromatography (GC)-mass spectrometry (MS) with simultaneous element-specific detection using a sulfur chemiluminescence detector (SCD) and a nitrogen chemiluminescence detector (NCD). Sequential heart-cuts of the 16 sulfur fractions were used to identify each individual sulfur compound in the unaged whisky. Twenty sulfur compounds were positively identified by a MS library search, linear retention indices (LRI), and formula identification using MS calibration software. Additionally eight formulas were also identified for unknown sulfur compounds. Simultaneous heart-cuts of the 16 sulfur fractions were used to produce the (2)D RTL GC-SCD chromatograms for principal component analysis. PCA of the (2)D RTL GC-SCD data clearly demonstrated the difference between unaged and aged whisky, as well as two different whisky samples. Fourteen sulfur compounds could be characterized as key sulfur compounds responsible for the changes in the aging step and/or the difference between two kinds of whisky samples. The determined values of the key sulfur compounds were in the range of 0.3-210 ng mL(-1) (RSD: 0.37-12%, n=3).

  13. Gypsy Field Project in Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    John P. Castagna; William J. Lamb; Carlos Moreno; Roger Young; Lynn Soreghan

    2000-09-19

    The objective of the Gypsy Project was to properly calculate seismic attributes and integrate these into a reservoir characterization project. Significant progress was made on the project in four areas. (1) Attenuation: In order for seismic inversion for rock properties or calculation of seismic attributes used to estimate rock properties to be performed validly, it is necessary to deal with seismic data that has had true amplitude and frequency content restored to account for earth filtering effects that are generally not included in seismic reservoir characterization methodologies. This requires the accurate measurement of seismic attenuation, something that is rarely achieved in practice. It is hoped that such measurements may also provide additional independent seismic attributes for use in reservoir characterization studies. In 2000, we were concerned with the ground truthing of attenuation measurements in the vicinity of wells. Our approach to the problem is one of extracting as time varying wavelet and relating temporal variations in the wavelet to an attenuation model of the earth. This method has the advantage of correcting for temporal variations in the reflectivity spectrum of the earth which confound the spectral ratio methodology which is the most commonly applied means of measuring attenuation from surface seismic data. Part I of the report describes our efforts in seismic attenuation as applied to the Gypsy data. (2) Optimal Attributes: A bewildering array of seismic attributes is available to the reservoir geoscientist to try to establish correlations to rock properties. Ultimately, the use of such a large number of degrees of freedom in the search for correlations with limited well control leads to common misapplication of statistically insignificant results which yields invalid predictions. Cross-validation against unused wells can be used to recognize such problems, but does not offer a solution to the question of which attributes should be used

  14. Herbs and spices: characterization and quantitation of biologically-active markers for routine quality control by multiple headspace solid-phase microextraction combined with separative or non-separative analysis.

    Science.gov (United States)

    Sgorbini, Barbara; Bicchi, Carlo; Cagliero, Cecilia; Cordero, Chiara; Liberto, Erica; Rubiolo, Patrizia

    2015-01-09

    Herbs and spices are used worldwide as food flavoring, thus determination of their identity, origin, and quality is mandatory for safe human consumption. An analysis strategy based on separative (HS-SPME-GC-MS) and non-separative (HS-SPME-MS) approaches is proposed for the volatile fraction of herbs and spices, for quality control and to quantify the aromatic markers with a single analysis directly on the plant material as such. Eight-to-ten lots of each of the following herbs/spices were considered: cloves (Syzygium aromaticum (L.) Merr. & Perry), American peppertree (Schinus molle L.), black pepper and white pepper (Piper nigrum L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.). Homogeneity, origin, and chemotypes of the investigated lots of each herb/spice were defined by fingerprinting, through statistical elaboration with principal component analysis (PCA). Characterizing aromatic markers were directly quantified on the solid matrix through multiple headspace extraction-HS-SPME (MHS-SPME). Reliable results were obtained with both separative and non-separative methods (where the latter were applicable); the two were in full agreement, RSD% ranging from 1.8 to 7.7% for eugenol in cloves, 2.2-18.4% for carvacrol+thymol in thyme, and 3.1-16.8% for thujones in sage.

  15. Launch Vehicle Design Process Characterization Enables Design/Project Tool

    Science.gov (United States)

    Blair, J. C.; Ryan, R. S.; Schutzenhofer, L. A.; Robinson, Nancy (Technical Monitor)

    2001-01-01

    The objectives of the project described in this viewgraph presentation included the following: (1) Provide an overview characterization of the launch vehicle design process; and (2) Delineate design/project tool to identify, document, and track pertinent data.

  16. A Characterization of Projective-free Rings

    Institute of Scientific and Technical Information of China (English)

    P.M. Cohn

    2003-01-01

    A simple condition is given for a projective module to be free, in terms of the matrix presenting it. This leads to a criterion for a ring to be projective-free,and it provides a simple proof that Sylvester domains are projective-free.

  17. Yucca Mountain Site Characterization Project Technical Data Catalog; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-06-30

    The June 1, 1985 DOE/NRC Site-Specific Procedural Agreement for Geologic Repository Site Investigation and Characterization Program requires the DOE to develop and maintain a catalog of data which will be updated and provided to the NRC at least quarterly. This catalog is to include a description of the data; the time (date), place, and method of acquisition; and where it may be examined. The Yucca Mountain Site Characterization Project (YMP) Technical Data Catalog is published and distributed in accordance with the requirements of the Site-Specific Agreement. The YMP Technical Data Catalog is a report based on reference information contained in the YMP Automated Technical Data Tracking System (ATDT). The reference information is provided by Participants for data acquired or developed in support of the YMP. The Technical Data Catalog is updated quarterly and published in the month following the end of each quarter. This edition of the Technical Data Catalog supersedes the edition dated March 31, 1992.

  18. Headspace - Guided Meditation and Mindfulness Techniques.

    Science.gov (United States)

    2016-08-03

    Mindfulness has been recommended by the National Institute for Health and Care Excellence and the NHS to help mental wellbeing, but can the Headspace app be used by nurses and health professionals in clinical settings?

  19. Characterization of Ash Standards for the Residues Project

    CERN Document Server

    Westsik, G A

    2001-01-01

    Measurements have been completed to characterize the plutonium content and isotopic composition of ash standards that are or may be used as quality control check sources for the Residues Stabilization Project. These standards are for use as check sources for the Segmented Gamma Scan Assay System (SGSAS) employed for the Residues Stabilization Project.

  20. Final Hanford Site Transuranic (TRU) Waste Characterization QA Project Plan

    Energy Technology Data Exchange (ETDEWEB)

    GREAGER, T.M.

    1999-12-14

    The Transuranic Waste Characterization Quality Assurance Program Plan required each U.S. Department of Energy (DOE) site that characterizes transuranic waste to be sent the Waste Isolation Pilot Plan that addresses applicable requirements specified in the quality assurance project plan (QAPP).

  1. Hot-Gas Filter Ash Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, M.L.; Hurley, J.P.; Dockter, B.A.; O`Keefe, C.A.

    1997-07-01

    Large-scale hot-gas filter testing over the past 10 years has revealed numerous cases of cake buildup on filter elements that has been difficult, if not impossible, to remove. At times, the cake can blind or bridge between candle filters, leading to filter failure. Physical factors, including particle-size distribution, particle shape, the aerodynamics of deposition, and system temperature, contribute to the difficulty in removing the cake, but chemical factors such as surface composition and gas-solid reactions also play roles in helping to bond the ash to the filters or to itself. This project is designed to perform the research necessary to determine the fuel-, sorbent-, and operations-related conditions that lead to blinding or bridging of hot-gas particle filters. The objectives of the project are threefold: (1) Determine the mechanisms by which a difficult-to-clean ash is formed and how it bridges hot-gas filters (2) Develop a method to determine the rate of bridging based on analyses of the feed coal and sorbent, filter properties, and system operating conditions and (3) Suggest and test ways to prevent filter bridging.

  2. AMMONIA CONCENTRATION IN SALTSTONE HEADSPACE SUMMARY REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Zamecnik, J; Alex Cozzi, A

    2008-09-26

    The Saltstone Facility Documented Safety Analysis (DSA) is under revision to accommodate changes in the Composite Lower Flammability Limit (CLFL) from the introduction of Isopar into Tank 50. Saltstone samples were prepared with an 'MCU' type salt solution spiked with ammonia. The ammonia released from the saltstone was captured and analyzed. The ammonia concentration found in the headspace of samples maintained at 95 C and 1 atm was, to 95% confidence, less than or equal to 3.9 mg/L. Tank 50 is fed by several influent streams. The salt solution from Tank 50 is pumped to the salt feed tank (SFT) in the Saltstone Production Facility (SPF). The premix materials cement, slag and fly ash are blended together prior to transfer to the grout mixer. The premix is fed to the grout mixer in the SPF and the salt solution is incorporated into the premix in the grout mixer, yielding saltstone slurry. The saltstone slurry drops into a hopper and then is pumped to the vault. The Saltstone Facility Documented Safety Analysis (DSA) is under revision to accommodate changes in the Composite Lower Flammability Limit (CLFL) from the introduction of Isopar{reg_sign} L into Tank 50. Waste Solidification-Engineering requested that the Savannah River National Laboratory (SRNL) perform testing to characterize the release of ammonia in curing saltstone at 95 C. The test temperature represents the maximum allowable temperature in the Saltstone Disposal Facility (SDF). Ammonia may be present in the salt solution and premix materials, or may be produced by chemical reactions when the premix and salt solution are combined. A final report (SRNS-STI-2008-00120, Rev. 0) will be issued that will cover in more depth the information presented in this report.

  3. Letter of Intent for RPP Characterization Program Process Engineering and Hanford Analytical Services and Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    ADAMS, M.R.

    2000-02-25

    The Characterization Project level of success achieved by the River Protection Project (RPP) is determined by the effectiveness of several organizations across RPP working together. The requirements, expectations, interrelationships, and performance criteria for each of these organizations were examined in order to understand the performances necessary to achieve characterization objectives. This Letter of Intent documents the results of the above examination. It formalizes the details of interfaces, working agreements, and requirements for obtaining and transferring tank waste samples from the Tank Farm System (RPP Process Engineering, Characterization Project Operations, and RPP Quality Assurance) to the characterization laboratory complex (222-S Laboratory, Waste Sampling and Characterization Facility, and the Hanford Analytical Service Program) and for the laboratory complex analysis and reporting of analytical results.

  4. Method for improving accuracy in full evaporation headspace analysis.

    Science.gov (United States)

    Xie, Wei-Qi; Chai, Xin-Sheng

    2017-03-21

    We report a new headspace analytical method in which multiple headspace extraction is incorporated with the full evaporation technique. The pressure uncertainty caused by the solid content change in the samples has a great impact to the measurement accuracy in the conventional full evaporation headspace analysis. The results (using ethanol solution as the model sample) showed that the present technique is effective to minimize such a problem. The proposed full evaporation multiple headspace extraction analysis technique is also automated and practical, and which could greatly broaden the applications of the full-evaporation-based headspace analysis. This article is protected by copyright. All rights reserved.

  5. Statistical Modeling Efforts for Headspace Gas

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, Brian Phillip [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-17

    The purpose of this document is to describe the statistical modeling effort for gas concentrations in WIPP storage containers. The concentration (in ppm) of CO2 in the headspace volume of standard waste box (SWB) 68685 is shown. A Bayesian approach and an adaptive Metropolis-Hastings algorithm were used.

  6. GAS ANALYSES FROM HEADSPACE OF PLUTONIUM-BEARING MATERIALS CONTAINERS

    Energy Technology Data Exchange (ETDEWEB)

    Almond, P.; Livingston, R.; Traver, L.; Arnold, M.; Bridges, N.; Kessinger, G.; Duffey, J.

    2010-02-01

    The Savannah River National Laboratory (SRNL) 3013 destructive examination program performs surveillances on 3013 containers originating from multiple sites across the DOE complex. The bases for the packaging, storage, and surveillance activities are derived from the Department of Energy's 3013 Standard (DOE-STD-3013-2004). During destructive examination, headspace gas samples are obtained from the 3013 inner container and the annulus between the outer and inner containers. To characterize gas species, the samples are analyzed by gas chromatography (GC), direct-inlet mass spectrometry (DIMS), and Fourier-transform infrared spectroscopy (FTIR). The GC results, as well as other parameters, are utilized as input into the gas evaluation software tool (GEST) program for computation of pre-puncture gas compositions and pressures. Over 30 containers from the Hanford Site and the Rocky Flats Environmental Technology Site (RFETS) have been examined in the first three years of the surveillance program. Several containers were shown to have appreciable hydrogen content (some greater than 30 mol %), yet little or no oxygen was detected in any of the containers, including those exhibiting high hydrogen concentrations. Characteristics including moisture content, surface area, and material composition, along with the headspace gas composition, are utilized in an attempt to explain the chemical behavior of the packaged materials.

  7. Final Hanford Site Transuranic (TRU) Waste Characterization QA Project Plan

    Energy Technology Data Exchange (ETDEWEB)

    GREAGER, T.M.

    2000-12-06

    The Quality Assurance Project Plan (QAPjP) has been prepared for waste characterization activities to be conducted by the Transuranic (TRU) Project at the Hanford Site to meet requirements set forth in the Waste Isolation Pilot Plan (WIPP) Hazardous Waste Facility Permit, 4890139088-TSDF, Attachment B, including Attachments B1 through B6 (WAP) (DOE, 1999a). The QAPjP describes the waste characterization requirements and includes test methods, details of planned waste sampling and analysis, and a description of the waste characterization and verification process. In addition, the QAPjP includes a description of the quality assurance/quality control (QA/QC) requirements for the waste characterization program. Before TRU waste is shipped to the WIPP site by the TRU Project, all applicable requirements of the QAPjP shall be implemented. Additional requirements necessary for transportation to waste disposal at WIPP can be found in the ''Quality Assurance Program Document'' (DOE 1999b) and HNF-2600, ''Hanford Site Transuranic Waste Certification Plan.'' TRU mixed waste contains both TRU radioactive and hazardous components, as defined in the WLPP-WAP. The waste is designated and separately packaged as either contact-handled (CH) or remote-handled (RH), based on the radiological dose rate at the surface of the waste container. RH TRU wastes are not currently shipped to the WIPP facility.

  8. Reliable characterization of coffee bean aroma profiles by automated headspace solid phase microextraction-gas chromatography-mass spectrometry with the support of a dual-filter mass spectra library.

    Science.gov (United States)

    Mondello, Luigi; Costa, Rosaria; Tranchida, Peter Quinto; Dugo, Paola; Lo Presti, Maria; Festa, Saverio; Fazio, Alessia; Dugo, Giovanni

    2005-06-01

    This investigation is based on the automated solid phase microextraction GC-MS analysis of the volatile fraction of a variety of coffee bean matrices. Volatile analytes were extracted by headspace (HS)-SPME which was achieved with the support of automated instrumentation. The research was directed towards various important aspects relating to coffee aroma analysis: monitoring of the volatile fraction formation during roasting; chromatographic differentiation of the two main coffee species (Arabica and Robusta) and of a single species from different geographical origins; evaluation of the influence of specific industrial treatments prior to roasting. Reliable peak assignment was carried out through the use of a recently laboratory-constructed "flavour and fragrance" library and a dual-filter MS spectral search procedure. Further emphasis was placed on the automated SPME instrumentation and on its ability to supply highly repeatable chromatographic data.

  9. Quality Assurance Project Plan for waste tank vapor characterization

    Energy Technology Data Exchange (ETDEWEB)

    Suydam, C.D. Jr.

    1993-12-01

    This Quality Assurance Project Plan, WHC-SD-WM-QAPP-013, applies to four separate vapor sampling tasks associated with Phases 1 and 2 of the Tank Vapor Issue Resolution Program and support of the Rotary Mode Core Drilling Portable Exhauster Permit. These tasks focus on employee safety concerns and tank ventilation emission control design requirements. Previous characterization efforts and studies are of insufficient accuracy to adequately define the problem. It is believed that the technology and maturity of sampling and analytical methods can be sufficiently developed to allow the characterization of the constituents of the tank vapor space.

  10. Generalized projection retrieval of dispersion scans for ultrashort pulse characterization

    CERN Document Server

    Miranda, Miguel; Guo, Chen; Harth, Anne; Louisy, Maite; Neoricic, Lana; L'Huillier, Anne; Arnold, Cord L

    2016-01-01

    We present a retrieval algorithm based on generalized projections for ultrashort pulse characterization using dispersion scan (d-scan). The new algorithm is tested on several simulated cases and in two different experimental cases in the few-cycle regime. The proposed algorithm is much faster and leads to a drastic reduction of retrieval times, but performs less robust in the retrieval of noisy d-scan traces compared to the standard algorithm.

  11. Potential application of microsensor technology in radioactive waste management with emphasis on headspace gas detection.

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Chad Edward; Thomas, Michael Loren; Wright, Jerome L.; Pohl, Phillip Isabio; Hughes, Robert Clark; Wang, Yifeng; McGrath, Lucas K.; Ho, Clifford Kuofei; Gao, Huizhen

    2004-09-01

    Waste characterization is probably the most costly part of radioactive waste management. An important part of this characterization is the measurements of headspace gas in waste containers in order to demonstrate the compliance with Resource Conservation and Recovery Act (RCRA) or transportation requirements. The traditional chemical analysis methods, which include all steps of gas sampling, sample shipment and laboratory analysis, are expensive and time-consuming as well as increasing worker's exposure to hazardous environments. Therefore, an alternative technique that can provide quick, in-situ, and real-time detections of headspace gas compositions is highly desirable. This report summarizes the results obtained from a Laboratory Directed Research & Development (LDRD) project entitled 'Potential Application of Microsensor Technology in Radioactive Waste Management with Emphasis on Headspace Gas Detection'. The objective of this project is to bridge the technical gap between the current status of microsensor development and the intended applications of these sensors in nuclear waste management. The major results are summarized below: {sm_bullet} A literature review was conducted on the regulatory requirements for headspace gas sampling/analysis in waste characterization and monitoring. The most relevant gaseous species and the related physiochemical environments were identified. It was found that preconcentrators might be needed in order for chemiresistor sensors to meet desired detection {sm_bullet} A long-term stability test was conducted for a polymer-based chemresistor sensor array. Significant drifts were observed over the time duration of one month. Such drifts should be taken into account for long-term in-situ monitoring. {sm_bullet} Several techniques were explored to improve the performance of sensor polymers. It has been demonstrated that freeze deposition of black carbon (CB)-polymer composite can effectively eliminate the so

  12. Dynamic headspace analysis of fresh tomato juices.

    Science.gov (United States)

    Sucan, M K; Russell, G F

    2001-01-01

    The methods used to isolate volatile compounds for GC analyses can cause profound effects on the quantitative and qualitative composition of the injected sample, and exert a great influence in the resultant bioactivity of volatiles. Especially with plant tissues like tomatoes, the isolation of volatile constituents using classical methods may yield results which are not representative of the chemicals present in the natural material. Headspace sampling methods may be advantageous in capturing the same volatile compounds emitted from tomatoes that are detected by the human nose. This study utilized an extremely sensitive dynamic headspace sampling with thermal desorption method to determine volatile components of fresh tomato juices. The method proved very sensitive for the isolation of tomato volatiles and concentrations of flavor compounds were much greater than related literature studies.

  13. Technical note: Headspace analysis of explosive compounds using a novel sampling chamber.

    Science.gov (United States)

    DeGreeff, Lauryn; Rogers, Duane A; Katilie, Christopher; Johnson, Kevin; Rose-Pehrsson, Susan

    2015-03-01

    The development of instruments and methods for explosive vapor detection is a continually evolving field of interest. A thorough understanding of the characteristic vapor signatures of explosive material is imperative for the development and testing of new and current detectors. In this research a headspace sampling chamber was designed to contain explosive materials for the controlled, reproducible sampling and characterization of vapors associated with these materials. In a detonation test, the chamber was shown to contain an explosion equivalent to three grams of trinitrotoluene (TNT) without damage to the chamber. The efficacy of the chamber in controlled headspace sampling was evaluated in laboratory tests with bulk explosive materials. Small quantities of TNT, triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD) were separately placed in the sampling chamber, and the headspace of each material was analyzed by gas chromatography/mass spectrometry (GC/MS) with online cryogenic trapping to yield characteristic vapor signatures for each explosive compound. Chamber sampling conditions, temperature and sampling time, were varied to demonstrate suitability for precise headspace analysis.

  14. Static and dynamic headspace analysis of instant coffee blends by proton-transfer-reaction mass spectrometry.

    Science.gov (United States)

    Romano, Andrea; Gaysinsky, Sylvia; Czepa, Andreas; Del Pulgar, José Sanchez; Cappellin, Luca; Biasioli, Franco

    2015-09-01

    Instant coffee is a widespread product, generally related to a high consumer acceptability, also because of its ease of preparation. The present work addresses the characterization of the headspace of freshly brewed instant coffees resulting from different blends, during and immediately after preparation. The sample set consisted of 10 coffees, obtained by mixing three different blends in different proportions. The employment of Proton Transfer Reaction-Mass Spectrometry (PTR-MS) allowed for direct and real-time sampling from the headspace, under conditions that mimic those that are encountered above the cup during and right after brewing. Different coffee brews were separated on the basis of the respective volatile profiles, and data showed good consistency with the respective blend compositions. When the headspace evolution was monitored during preparation, similar results were obtained in terms of blend separation; moreover, different blends displayed different and reproducible 'signatures' in terms of time evolution. A straightforward method for the prediction of headspace composition is proposed, allowing to predict the volatile profiles of two-component and three-component blends on the basis of the respective parent components. Overall, the results constitute a successful example of the applicability of PTR-MS as a tool for product development in food science. Copyright © 2015 John Wiley & Sons, Ltd.

  15. Visualization and characterization of users in a citizen science project

    Science.gov (United States)

    Morais, Alessandra M. M.; Raddick, Jordan; Coelho dos Santos, Rafael D.

    2013-05-01

    Recent technological advances allowed the creation and use of internet-based systems where many users can collaborate gathering and sharing information for specific or general purposes: social networks, e-commerce review systems, collaborative knowledge systems, etc. Since most of the data collected in these systems is user-generated, understanding of the motivations and general behavior of users is a very important issue. Of particular interest are citizen science projects, where users without scientific training are asked for collaboration labeling and classifying information (either automatically by giving away idle computer time or manually by actually seeing data and providing information about it). Understanding behavior of users of those types of data collection systems may help increase the involvement of the users, categorize users accordingly to different parameters, facilitate their collaboration with the systems, design better user interfaces, and allow better planning and deployment of similar projects and systems. Behavior of those users could be estimated through analysis of their collaboration track: registers of which user did what and when can be easily and unobtrusively collected in several different ways, the simplest being a log of activities. In this paper we present some results on the visualization and characterization of almost 150.000 users with more than 80.000.000 collaborations with a citizen science project - Galaxy Zoo I, which asked users to classify galaxies' images. Basic visualization techniques are not applicable due to the number of users, so techniques to characterize users' behavior based on feature extraction and clustering are used.

  16. Characterization of the Typical Potent Odorants in Chinese Roasted Sesame-like Flavor Type Liquor by Headspace Solid Phase Microextraction-Aroma Extract Dilution Analysis, with Special Emphasis on Sulfur-Containing Odorants.

    Science.gov (United States)

    Sha, Sha; Chen, Shuang; Qian, Michael; Wang, Chengcheng; Xu, Yan

    2017-01-11

    The aroma profile of Chinese roasted sesame-like flavor type liquor was investigated by means of headspace solid phase microextraction-aroma extract dilution analysis (HS-SPME-AEDA). Sixty-three odor-active regions were detected by HS-SPME-AEDA with flavor dilution (FD) factors >5, and 58 of these were further identified. Among them, ethyl hexanoate, 2-furfurylthiol, dimethyl trisulfide, 3-methylbutanal, ethyl butanoate, ethyl 2-methylbutanoate, ethyl pentanoate, and ethyl 4-methylpentanoate appeared with the highest FD factors. In particular, eight sulfur-containing odorants were identified to be potentially important to roasted sesame-like flavor type liquor. The concentration of these odor-active compounds was further quantitated by combination of four different quantitative measurements, and 36 odorants had concentrations higher than their corresponding odor thresholds. On the basis of the odor activity values (OAVs), 2-furfurylthiol (OAV 1182), dimethyl trisulfide (OAV 220), β-damascenone (OAV 116), and methional (OAV 99) could be responsible for the unique aroma of roasted sesame-like flavor type liquor. An aroma recombination model prepared by mixing 36 aroma compounds with OAVs >1 showed a good similarity to the aroma of the original roasted sesame-like flavor type liquor. For the first time, 2-furfurylthiol was determined to be a typical potent odorant in roasted sesame-like flavor type liquor by omission study.

  17. Characterizing symmetries in a projected entangled pair state

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Garcia, D; Gonzalez-Guillen, C E [Departamento Analisis Matematico and IMI, Universidad Complutense de Madrid, 28040 Madrid (Spain); Sanz, M; Cirac, J I [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Str. 1, 85748 Garching (Germany); Wolf, M M [Niels Bohr Institute, Blegdamsvej 17, 2100 Copenhagen (Denmark)], E-mail: dperez@mat.ucm.es

    2010-02-15

    We show that two different tensors defining the same translational invariant injective projected entangled pair state (PEPS) in a square lattice must be the same up to a trivial gauge freedom. This allows us to characterize the existence of any local or spatial symmetry in the state. As an application of these results we prove that a SU(2) invariant PEPS with half-integer spin cannot be injective, which can be seen as a Lieb-Shultz-Mattis theorem in this context. We also give the natural generalization for U(1) symmetry in the spirit of Oshikawa-Yamanaka-Affleck, and show that a PEPS with Wilson loops cannot be injective.

  18. Hydrological, geomorphological and ecological river characterization: PELLIDRAC (Alcotra Project)

    Science.gov (United States)

    Piccione, S.; Comino, E.; Rosso, M.; Chouquet, I.

    2012-04-01

    PELLIDRAC Project, allowed to highlight both the positive characteristics that the critical ones of the two analyzed rivers: Pellice river in Italy and Drac river, in French territory. We also analyzed different methods of river management to identify the best one for risk mitigation (hydraulic and concerning populations) and for water bodies and riparian environment protection. Main activities were inspections, to allow a direct knowledge of investigated areas, application of environmental and morphological indices, hydraulic simulations and evaluation of planimetrical variations and elevation changes of riverbed. The work shows two not homogeneous river ecosystems, characterized by high erosion of the banks and progressive lowering of riverbed bottom that leads to local outcrops of the substrate (most evident on Drac); to fight against erosion, many bank protections have been built. In addition, we observed human actions, such as riverbed remodeling and extraction of material, that cause negative impacts on riparian areas. About ecological and environmental aspects, we identified some areas with good river functionality and high level of naturalness, mainly characterized by the presence of wetlands and riparian vegetation well-developed and diversified. In analyzed territories, we proposed some interventions, such as creation of new wetlands, widening of some riverbed sections and a material recharge, attempting to mitigate founded problems. PELLIDRAC Project conclusion is not a point of arrival but a point of departure for further planning of specific interventions on river ecosystems, aimed at good management of water courses and at improvement of riparian populations living conditions.

  19. GNS Castor V/21 Headspace Gas Sampling 2014

    Energy Technology Data Exchange (ETDEWEB)

    Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-01-01

    Prior to performing an internal visual inspection, samples of the headspace gas of the GNS Castor V/21 cask were taken on June 12, 2014. These samples were taken in support of the CREIPI/Japanese nuclear industry effort to validate fuel integrity without visual inspection by measuring the 85Kr content of the cask headspace

  20. Project plan for the Background Soil Characterization Project on the Oak Ridge Reservation, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    1992-08-01

    The Background Soil characterization Project (BSCP) will provide background concentration levels of selected metals, organic compounds, and radionuclides in soils from uncontaminated on-site areas at the Oak Ridge Reservation (ORR), and off-site in the western part of Roane County and the eastern part of Anderson County. The BSCP will establish a database, recommend how to use the data for contaminated site assessment, and provide estimates of the potential human health and environmental risks associated with the background level concentrations of potentially hazardous constituents.

  1. Fluid characterization for miscible EOR projects and CO2 sequestration

    DEFF Research Database (Denmark)

    Jessen, Kristian; Stenby, Erling Halfdan

    2007-01-01

    Accurate performance prediction of miscible enhanced-oil-recovery (EOR) projects or CO, sequestration in depleted oil and gas reservoirs relies in part on the ability of an equation-of-state (EOS) model to adequately represent the properties of a wide range of mixtures of the resident fluid...... and the injected fluid(s). The mixtures that form when gas displaces oil in a porous medium will, in many cases, differ significantly from compositions created in swelling tests and other standard pressure/volume/temperature (PVT) experiments. Multicontact experiments (e.g., slimtube displacements) are often used...... in the data reduction and demonstrate that for some gas/oil systems, swelling tests do not contribute to a more accurate prediction of multicontact miscibility. Finally, we report on the impact that use of EOS models based on different characterization procedures can have on recovery predictions from dynamic...

  2. Preliminary Characterization Results from the DebriSat Project

    Science.gov (United States)

    Rivero, M.; Shiotani, B.; Kleespies, J.; Toledo-Burdett, R.; Moraguez, M.; Carrasquila, M.; Fitz-Coy, N.; Liou, J.-C.; Sorge, M.; Huynh, T.

    2016-01-01

    The DebriSat project is a continuing effort sponsored by NASA and DoD to update existing break-up models using data obtained from two separate hypervelocity impact tests used to simulate on-orbit collisions. To protect the fragments resulting from the impact tests, "soft-catch" arenas made of polyurethane foam panels were utilized. After each impact test, the test chamber was cleaned and debris resulting from the catastrophic demise of the test article were collected and shipped to the University of Florida for post-impact processing. The post-impact processing activities include collecting, characterizing, and cataloging of the fragments. Since the impact tests, a team of students has been working to characterize the fragments in terms of their mass, size, shape, color and material content. The focus of the 20 months since the impact tests has been on the collection of 2 millimeters- and larger fragments resulting from impact test on the 56 kilogram-representative LEO (Low Earth Orbit) satellite referred to as DebriSat. To date we have recovered in excess of 115,000 fragments, 30,000 more than the prediction of 85,000 fragments from the existing model. We continue to collect fragments but have transitioned to the characterization phase of the post-impact activities. Since the start of the characterization phase, the focus has been to utilize automation to (i) expedite fragment characterization process and (ii) minimize human-in-the- loop. We have developed and implemented such automated processes; e.g., we have automated the data entry process to reduce operator errors during transcription of the measurement data. However, at all steps of the process, there is human oversight to ensure the integrity of the data. Additionally, we have developed and implemented repeatability and reproducibility tests to ensure that the instrumentation used in the characterization process is accurate and properly calibrated. In this paper, the implemented processes are described and

  3. Fault Hydrogeology Characterization for a Civil Infrastructure Project

    Science.gov (United States)

    Sholley, M. G.; Waterman, M. K.; Attanayake, P. M.

    2011-12-01

    Planning for the construction of an 18-ft diameter water conveyance tunnel in Southern California was made additionally complex due to the tunnel alignment crossing the San Andreas Fault and a tunnel portal within an area of elevated groundwater temperatures associated with branches/splays of the Arrowhead Spring fault system. This abstract describes the investigation techniques used to characterize the hydrogeology associated with these faults and the conceptual models developed to assist with hazard mitigation during construction. From an early phase of the project it was recognized that tunneling through the San Andreas Fault posed the risk of increased groundwater inflows and therefore potentially hazardous construction conditions. Characterization of the fault focused on estimating those parameters critical to the groundwater regime. In addition to geologic mapping, several boreholes were drilled and the cores logged to determine rock mass characteristics. Prior to installing monitoring wells in these boreholes, in-situ testing to determine hydraulic conductivity was conducted with a double packer system. Analysis of the packer test results demonstrated that factors found to have significant correspondence to hydraulic conductivity were depth of test and proximity to faults. The combination of rock mass characterization, hydraulic conductivity distribution, and water levels were then used to estimate groundwater inflows to the tunnel. The inflow estimates were developed to provide a measure for determining the need to prevent and control the inflows and in identifying likely delays in construction progress. Two semi-empirical methods were used to evaluate the probable magnitude of tunnel inflow. This combination of field techniques and analyses led to a preliminary understanding of the hydrogeological characteristics of the San Andreas Fault and the potential interaction between tunnel construction and the groundwater resource. A detailed understanding of the

  4. TWRS phase 1 infrastructure project (W-519) characterization

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, C.J.

    1998-09-24

    In order to treat the mixed radioactive and hazardous waste stored in 177 underground tanks, the Tank Waste Remediation System (TWRS) program is developing a `demonstration` site for treatment and immobilization of these wastes by a private contractor. Project W-519 is providing the infrastructure support to this site by developing the designs and emplacing required pipelines, roads, electrical, etc. In support of the TWRS Phase 1 Infrastructure Project (W-519) Characterization, Numatec Hanford Corporation (NHC) contracted with Waste Management Federal Services, Inc., Northwest Operations (WMNW) to investigate a number of locations in and just outside the 200 East Area eastern fenceline boundary. These areas consisted of known or suspected waste lines or waste sites that could potentially impact the construction and emplacement of the proposed facility improvements, including waterlines and roads. These sites were all located subsurface and sugaring would be required to obtain sample material from the desired depth. The soils would then be sampled and submitted to the laboratory for analysis of radioactivity.

  5. Method Development for Container Closure Integrity Evaluation via Headspace Gas Ingress by Using Frequency Modulation Spectroscopy.

    Science.gov (United States)

    Victor, Ken G; Levac, Lauren; Timmins, Michael; Veale, James

    2017-07-20

    USP Section 3.5 states that "A deterministic leak test method having the ability to detect leaks at the product's maximum allowable leakage limit is preferred when establishing the inherent integrity of a container-closure system." Ideally, container closure integrity (CCI) of parenteral packaging would be evaluated by measuring a physical property that is sensitive to the presence of any package defect that breaches package integrity by increasing its leakage above its maximum allowable leakage limit (MALL). The primary goals of the work presented herein were to demonstrate the viability of the non-destructive, deterministic method known as laser-based gas headspace analysis for evaluating CCI and to provide a physical model for predicting leak rates for a variety of container volumes, headspace conditions and defect sizes. The results demonstrate that laser-based headspace analysis provides sensitive, accurate and reproducible measurements of the gas ingress into glass vial-stopper package assemblies that are under either diffusive or effusive leak conditions. Two different types of positive controls were examined. First, laser-drilled micro-holes in thin metal disks that were crimped on top of 15R glass vials served as positive controls with a well-characterized defect geometry. For these, a strong correlation was observed between the measured ingress parameter and the size of the defect for both diffusive and effusive conditions. Second, laser-drilled holes in the wall of glass vials served as controls that more closely simulate "real world" defects. Due to their complex defect geometries, their diffusive and effusive ingress parameters did not necessarily correlate; this is an important observation that has significant implications for standardizing the characterization of container defects. Regardless, laser-based headspace analysis could readily differentiate positive and negative controls for all leak conditions and the results provide a guide for method

  6. Yucca Mountain Site Characterization Project technical data catalog: Quarterly supplement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The Department of Energy (DOE)/Nuclear Regulatory Commission (NRC) Site-Specific Procedural Agreement for Geologic Repository Site Investigation and Characterization Program requires the DOE to develop and maintain a catalog of data which will be updated and provided to the NRC at least quarterly. This catalog is to include a description of the data; the time (date), place, and method of acquisition; and where the data may be examined. The Yucca Mountain Site Characterization Project (YMP) Technical Data Catalog is published and distributed-in accordance with the requirements of the Site-Specific Agreement. The YMP Technical Data Catalog is a report based on reference information contained in the YMP Automated Technical Data Tracking System (ATDT). The reference information is provided by Participants for data acquired or developed in support of the YMP. The Technical Data Catalog is updated quarterly and distributed in the month following the end of each quarter. A complete revision to the catalog is published at the end of each fiscal year. Supplements to the end-of-year edition are published each quarter. These supplements provide information related to new data items not included in previous quarterly updates and data items affected by changes to previously published reference information. The Technical Data Catalog, dated September 30, 1994, should be retained as the baseline document for the supplements until the end-of-year revision is published and distributed in October 1995.

  7. Yucca Mountain Site Characterization Project technical data catalog quarterly supplement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-31

    The Department of Energy (DOE)/Nuclear Regulatory Commission (NRC) Site-Specific Procedural Agreement for Geologic Repository Site Investigation and Characterization Program requires the DOE to develop and maintain a catalog of data which will be updated and provided to the NRC at least quarterly. This catalog is to include a description of the data; the time (date), place, and method of acquisition; and where the data may be examined. The Yucca Mountain Site Characterization Project (YMP) Technical Data Catalog is published and distributed in accordance with t requirements of the Site-Specific Agreement. The YMP Technical Data Catalog is a report based on reference information contained in the YMP Automated Technical Data Tracking System (ATDT). The reference information is provided by Participants for data acquired or developed in support of the YMP. The Technical Data Catalog is updated quarterly and distributed in the month following the end of each quarter. A complete revision to the catalog is published at the end of each fiscal year. Supplements to the end-of-year edition are published each quarter. These supplements provide information related to new data items not included in previous quarterly updates and data items affected by changes to@ previously published reference information. The Technical Data Catalog, dated September 30, 1994, should be retained as the baseline document for the supplements until the end-of-year revision is published and distributed in October 1995.

  8. Yucca Mountain Site Characterization Project: Technical Data Catalog quarterly supplement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-31

    The March 21, 1993, Department of Energy (DOE)/Nuclear Regulatory Commission (NRC) Site-Specific Procedural Agreement for Geologic Repository Site Investigation and Characterization Program requires the DOE to develop and maintain a catalog of data which will be updated and provided to the NRC at least quarterly. This catalog is to include a description of the data; the time (date), place, and method of acquisition; and where it may be examined. The Yucca Mountain Site Characterization Project (YMP) Technical Data Catalog is published and distributed in accordance with the requirements of the Site-Specific Agreement. The YMP Technical Data Catalog is a report based on reference information contained in the YMP Automated Technical Data Tracking System (ATDT). The reference information is provided by Participants for data acquired or developed in support of the YMP. The Technical Data Catalog is updated quarterly and published in the month following the end of each quarter. A complete revision to the Catalog is published at the end of each fiscal year. Supplements to the end-of-year edition are published each quarter. These supplements provide information related to new data items not included in previous quarterly updates and data items affected by changes to previously published reference information. The Technical Data Catalog, dated September 30, 1993, should be retained as the baseline document for the supplements until the end-of-year revision is published and distributed in October 1994.

  9. Headspace chromatographic determination of water pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Otson, R.; Williams, D.T.

    1982-05-01

    A readily constructed, automated purging assembly, on-column trapping, and simultaneous use of flame ionization and electrolytic conductivity detectors were applied to develop a dynamic headspace gas chromatographic technique which was evaluated for the determination of 42 organic polluants in water. Detection limits of <1 ..mu..g/L and linear plots of peak area against concentration in the range 0.25-16 ..mu..g/L were obtained for 32 compounds. At aqueous concentrations of 4 and 16 ..mu..g/L, peak area precision of <10% relative standard deviation (RSD) for triplicate sample analysis and purging efficiencies of >75% were generally obtained. Storage of aqueous composite standard solutions at 4 and 16 ..mu..g/L for 6 weeks at 4/sup 0/C did not usually affect analytical results by more than +/- 15%.

  10. Gas flow headspace liquid phase microextraction.

    Science.gov (United States)

    Yang, Cui; Qiu, Jinxue; Ren, Chunyan; Piao, Xiangfan; Li, Xifeng; Wu, Xue; Li, Donghao

    2009-11-06

    There is a trend towards the use of enrichment techniques such as microextraction in the analysis of trace chemicals. Based on the theory of ideal gases, theory of gas chromatography and the original headspace liquid phase microextraction (HS-LPME) technique, a simple gas flow headspace liquid phase microextraction (GF-HS-LPME) technique has been developed, where the extracting gas phase volume is increased using a gas flow. The system is an open system, where an inert gas containing the target compounds flows continuously through a special gas outlet channel (D=1.8mm), and the target compounds are trapped on a solvent microdrop (2.4 microL) hanging on the microsyringe tip, as a result, a high enrichment factor is obtained. The parameters affecting the enrichment factor, such as the gas flow rate, the position of the microdrop, the diameter of the gas outlet channel, the temperatures of the extracting solvent and of the sample, and the extraction time, were systematically optimized for four types of polycyclic aromatic hydrocarbons. The results were compared with results obtained from HS-LPME. Under the optimized conditions (where the extraction time and the volume of the extracting sample vial were fixed at 20min and 10mL, respectively), detection limits (S/N=3) were approximately a factor of 4 lower than those for the original HS-LPME technique. The method was validated by comparison of the GF-HS-LPME and HS-LPME techniques using data for PAHs from environmental sediment samples.

  11. Headspace mass spectrometry methodology: application to oil spill identification in soils

    Energy Technology Data Exchange (ETDEWEB)

    Perez Pavon, J.L.; Garcia Pinto, C.; Moreno Cordero, B. [Universidad de Salamanca, Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias Quimicas, Salamanca (Spain); Guerrero Pena, A. [Universidad de Salamanca, Departamento de Quimica Analitica, Nutricion y Bromatologia, Facultad de Ciencias Quimicas, Salamanca (Spain); Laboratorio de Suelos, Plantas y Aguas, Campus Tabasco, Colegio de Postgraduados, Cardenas, Tabasco (Mexico)

    2008-05-15

    In the present work we report the results obtained with a methodology based on direct coupling of a headspace generator to a mass spectrometer for the identification of different types of petroleum crudes in polluted soils. With no prior treatment, the samples are subjected to the headspace generation process and the volatiles generated are introduced directly into the mass spectrometer, thereby obtaining a fingerprint of volatiles in the sample analysed. The mass spectrum corresponding to the mass/charge ratios (m/z) contains the information related to the composition of the headspace and is used as the analytical signal for the characterization of the samples. The signals obtained for the different samples were treated by chemometric techniques to obtain the desired information. The main advantage of the proposed methodology is that no prior chromatographic separation and no sample manipulation are required. The method is rapid, simple and, in view of the results, highly promising for the implementation of a new approach for oil spill identification in soils. (orig.)

  12. Multiple headspace extraction for gas detection in ionic liquids.

    Science.gov (United States)

    Müller, D; Fühl, M; Pinkwart, K; Baltes, N

    2014-10-16

    In this study multiple headspace extraction was used for the first time to measure the saturation concentration of carbon monoxide and oxygen in various ionic liquids (ILs). Many processes in ILs involve the reaction of gases so that the reactant solubility is not a mere characteristical parameter, but understanding the solubility of gases in ILs is required for assessing the feasibility of possible applications. Multiple headspace extraction has proofed to be a powerful tool to obtain solubilities in good accordance with literature data. The measured saturation concentration for carbon monoxide and oxygen in ILs based on rarely researched tetracyanoborates and other anions was in the range of 1.5-6.5mmol/L. The great advantage of multiple headspace extraction is that it is a nonexpensive method that can be realised in most analytical laboratories by combination of a simple gas chromatograph and an eligible headspace injector.

  13. Headspace solid-phase microextraction for wine volatile analysis.

    Science.gov (United States)

    Azzi-Achkouty, Samar; Estephan, Nathalie; Ouaini, Naïm; Rutledge, Douglas N

    2017-07-03

    The most commonly used technique to prepare samples for the analysis of wine volatile is the headspace solid-phase microextraction (HS-SPME). This method has gained popularity in last few years, as it is a unique solventless preparation technique. In this paper, a summary of recently published studies using HS-SPME for the analysis of wine aromas, with special emphasis on the method developed, has been compiled. Several papers are discussed in detail, mainly with respect to the SPME conditions used. A brief summary of the reviews related to HS-SPME analysis is given and discussed. Several parameters affecting the HS-SPME, such as the salt concentration and the agitation conditions, are used in the same way as used in several papers. The HS-SPME extraction proved to be sufficiently sensitive to satisfy legislative requirements related to low detection and quantification limits as well as method accuracy and precision requirements. However, in order to achieve the best performance and precision, the protocol needs to be optimized for each case. The effect of different parameters must be well characterized to ensure correct extraction and desorption to ensure the transfer of extracted compounds into the analytical system. The operating parameters, such as time, temperature, and agitation, must then be kept constant for all the samples.

  14. Hydrologic characterization of four cores from the Geysers Coring Project

    Energy Technology Data Exchange (ETDEWEB)

    Persoff, Peter; Hulen, Jeffrey B.

    1996-01-24

    Results of hydrologic tests conducted on four representative core plugs from Geysers Coring Project drill hole SB-15-D have been related to detailed mineralogic and textural characterization of the plugs to yield new information about permeability, porosity, and capillary-pressure characteristics of the uppermost Geysers steam reservoir and its immediately overlying caprock. The core plugs are all fine- to medium-grained, Franciscan-assemblage (late Mesozoic) metagraywacke with sparse Franciscan metamorphic quartz-calcite veins and late Cenozoic, hydrothermal quartz-calcite-pyrite veins. The matrices of three plugs from the caprock are rich in metamorphic mixed-layer illite/smectite and disseminated hydrothermal pyrite; the reservoir plug instead contains abundant illite and only minor pyrite. The reservoir plug and one caprock plug are sparsely disrupted by latest-stage, unmineralized microfractures which both follow and crosscut veinlets but which could be artifacts. Porosities of the plugs, measured by Boyles-law gas expansion, range between 1.9 and 2.5%. Gas permeability and Klinkenberg slip factor were calculated from gas-pressure-pulse-decay measurements using a specially designed permeameter with small (2 mL) reservoirs. Matrix permeabilities in the range 10-21 m² ( = 1 nanodarcy) were measured for two plugs that included mineral-filled veins but no unfilled microfractures. Greater permeabilities were measured on plugs that contained microfractures; at 500 psi net confining pressure, an effective aperture of 1.6 µm was estimated for one plug. Capillary pressure curves were determined for three cores by measuring saturation as weight gain of plugs equilibrated with atmospheres in which the relative humidity was controlled by saturated brines.

  15. Post Process Characterization of Friction Stir Welded Components Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna Innovations Incorporated proposes in this STTR Phase II project to continue development and validation of Luna's amplitude-dependent, nonlinear ultrasonic...

  16. Final Hanford Site Transuranic (TRU) Waste Characterization QA Project Plan

    Energy Technology Data Exchange (ETDEWEB)

    GREAGER, T.M.

    1999-09-09

    The Transuranic Waste Characterization Quality Assurance Program Plan required each US Department of Energy (DOE) site that characterizes transuranic waste to be sent the Waste Isolation Pilot Plan that addresses applicable requirements specified in the QAPP.

  17. Headspace-free setup of in vitro bioassays for the evaluation of volatile disinfection by-products.

    Science.gov (United States)

    Stalter, Daniel; Dutt, Mriga; Escher, Beate I

    2013-11-18

    The conventional setup of in vitro bioassays in microplates does not prevent the loss of volatile compounds, which hampers the toxicological characterization of waterborne volatile disinfection by-products (DBPs). To minimize the loss of volatile test chemicals, we adapted four in vitro bioassays to a headspace-free setup using eight volatile organic compounds (four trihalomethanes, 1,1-dichloroethene, bromoethane, and two haloacetonitriles) that cover a wide range of air-water partition coefficients. The nominal effect concentrations of the test chemicals decreased by up to three orders of magnitude when the conventional setup was changed to a headspace-free setup for the bacterial cytotoxicity assay using bioluminescence inhibition of Vibrio fischeri. The increase of apparent sensitivity correlated significantly with the air-water partition coefficient. Purge and trap GC/MS analysis revealed a reduced loss of dosed volatile compounds in the headspace free setup (78-130% of nominal concentration) compared to a substantial loss in the conventional set up (2-13% of the nominal concentration). The experimental effect concentrations converged with the headspace-free setup to the effect concentrations predicted by a QSAR model, confirming the suitability of the headspace-free approach to minimize the loss of volatile test chemicals. The analogue headspace-free design of the bacterial bioassays for genotoxicity (umuC assay) and mutagenicity (Ames fluctuation assay) increased the number of compounds detected as genotoxic or mutagenic from one to four and zero to two, respectively. In a bioassay with a mammalian cell line applied for detecting the induction of the Nrf-2-mediated oxidative stress response (AREc32 assay), the headspace-free setup improved the apparent sensitivity by less than one order of magnitude, presumably due to the retaining effect of the serum components in the medium, which is also reflected in the reduced aqueous concentrations of compounds. This

  18. Yucca Mountain Site Characterization Project bibliography, January--June 1995. Supplement 4, Add.3: An update

    Energy Technology Data Exchange (ETDEWEB)

    Stephan, P.M. [ed.

    1996-01-01

    Following a reorganization of the Office of Civilian Radioactive Waste Management in 1990, the Yucca Mountain Project was renamed Yucca Mountain Site Characterization Project. The title of this bibliography was also changed to Yucca Mountain Site Characterization Project Bibliography. Prior to August 5, 1988, this project was called the Nevada Nuclear Waste Storage Investigations. This bibliography contains information on this ongoing project that was added to the Department of Energy`s Energy Science and Technology Database from January 1, 1995, through June 30, 1995. The bibliography is categorized by principal project participating organization. Participant-sponsored subcontractor reports, papers, and articles are included in the sponsoring organization`s list. Another section contains information about publications on the Energy Science and Technology Database that were not sponsored by the project but have some relevance to it.

  19. Yucca Mountain Site Characterization Project Bibliography, January--June 1993. An update: Supplement 4, Addendum 1

    Energy Technology Data Exchange (ETDEWEB)

    Stephan, P.M. [ed.

    1995-01-01

    Following a reorganization of the Office of Civilian Radioactive Waste Management in 1990, the Yucca Mountain Project was renamed Yucca Mountain Site Characterization Project. The title of this bibliography was also changed to Yucca Mountain Site Characterization Project Bibliography. Prior to August 5, 1988, this project was called the Nevada Nuclear Waste Storage Investigations. This bibliography contains information on this ongoing project that was added to the Department of Energy`s Energy Science and Technology Database from January 1, 1994 through June 30, 1994. The bibliography is categorized by principal project participating organization. Participant-sponsored subcontractor reports, papers,and articles are included in the sponsoring organization`s list. Another section contains information about publications on the Energy Science and Technology Database that were not sponsored by the project but have some relevance to it.

  20. Characterizing and Manufacturing Multifunctional Radiation Shielding Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project addresses two vital problems for long-term space travel activities: radiation shielding and hydrogen storage for power and propulsion. While both...

  1. [Analysis of headspace constituents of Gardenia flower by GC/MS with solid-phase microextraction and dynamic headspace sampling].

    Science.gov (United States)

    Liu, B Z; Gao, Y

    2000-09-01

    The headspace constituents of fresh Gardenia flower were investigated by GC/MS. The headspace volatiles were sampled by solid-phase microextraction (SPME) and dynamic headspace sampling (DHS). SPME sampling was conducted with 100 microns PDMS fiber at 28 degrees C for 60 min. In DHS sampling, purified nitrogen was used as purging gas with a flow rate at 80 mL/min for 120 min. Tenax GR(20 mesh-40 mesh) was used as adsorbent and the volatiles were eluted by ether, and concentrated to 0.5 mL for GC/MS analysis. A Supelco-wax capillary column (30 m x 0.25 mm i.d. x 0.25 micron df) was employed in GC/MS analysis. Initial oven temperature was kept at 45 degrees C for 2 min, then raised to 250 degrees C at 4 degrees C/min, and kept at 250 degrees C for 10 min. According to SPME-GC/MS analysis, the main compounds in headspace of fresh Gardenia flower included farnesene(64.86%), cis-ocimene(29.33%), linalool(2.74%), cis-3-hexenyl tiglate(1.34%), methyl benzoate(0.25%). Results obtained from SPME and DHS sampling were also compared. In this study, SPME afforded a simpler and more sensitive sampling method, and much more accurate information about headspace volatiles of Gardenia flower.

  2. DQO Summary Report for 105-N/109-N Interim Safe Storage Project Waste Characterization

    Energy Technology Data Exchange (ETDEWEB)

    T. A. Lee

    2005-09-15

    The DQO summary report provides the results of the DQO process completed for waste characterization activities for the 105-N/109-N Reactor Interim Safe Storage Project including decommission, deactivate, decontaminate, and demolish activities for six associated buildings.

  3. Los Alamos National Laboratory Yucca Mountain Site Characterization Project 1995 quality program status report

    Energy Technology Data Exchange (ETDEWEB)

    Bolivar, S.L.

    1996-07-01

    This status report summarizes the activities and accomplishments of the Los Alamos National Laboratory Yucca Mountain Site Characterization Project`s (YMP`s) quality assurance program for January 1 to September 30, 1995. The report includes major sections on program activities and trend analysis.

  4. THz transceiver characterization : LDRD project 139363 final report.

    Energy Technology Data Exchange (ETDEWEB)

    Nordquist, Christopher Daniel; Wanke, Michael Clement; Cich, Michael Joseph; Reno, John Louis; Fuller, Charles T.; Wendt, Joel Robert; Lee, Mark; Grine, Albert D.

    2009-09-01

    LDRD Project 139363 supported experiments to quantify the performance characteristics of monolithically integrated Schottky diode + quantum cascade laser (QCL) heterodyne mixers at terahertz (THz) frequencies. These integrated mixers are the first all-semiconductor THz devices to successfully incorporate a rectifying diode directly into the optical waveguide of a QCL, obviating the conventional optical coupling between a THz local oscillator and rectifier in a heterodyne mixer system. This integrated mixer was shown to function as a true heterodyne receiver of an externally received THz signal, a breakthrough which may lead to more widespread acceptance of this new THz technology paradigm. In addition, questions about QCL mode shifting in response to temperature, bias, and external feedback, and to what extent internal frequency locking can improve stability have been answered under this project.

  5. Yucca Mountain Site Characterization Project Bibliography, July--December 1994: An update

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    Following a reorganization of the Office of Civilian Radioactive Waste Management in 1990, the Yucca Mountain Project was renamed Yucca Mountain Site Charactrization Project. The title of this bibliography was also changed to Yucca Mountain Site Characterization Project Bibliography. Prior to August 5, 1988, this project was called the Nevada Nuclear Waste Storage Investigations. This bibliography contains information on this ongoing project that was added to the Department of Energy`s Science and Technology Database from July 1, 1994 through December 31, 1994. The bibliography is categorized by principal project participating organization. Participant-sponsored subcontractor reports, papers, and articles are included in the sponsoring organization`s list. Another section contains information about publications on the Energy Science and Technology Database that were not sponsored by the project but have some relevance to it.

  6. An Economical Method for Static Headspace Enrichment for Arson Analysis

    Science.gov (United States)

    Olesen, Bjorn

    2010-01-01

    Static headspace analysis of accelerants from suspected arsons is accomplished by placing an arson sample in a sealed container with a carbon strip suspended above the sample. The sample is heated, cooled to room temperature, and then the organic components are extracted from the carbon strip with carbon disulfide followed by gas chromatography…

  7. Quality control of raw cows' milk by headspace analysis

    NARCIS (Netherlands)

    Hettinga, K.A.; Valenberg, van H.J.F.; Hooijdonk, van A.C.M.

    2008-01-01

    This study investigated whether headspace analysis of volatile components can be used for monitoring the quality of raw cows¿ milk. The detection of different quality defects caused by cows¿ feed, microbiological and chemical contamination, as well as enzymatic deterioration was studied. Fresh raw m

  8. A Survey of Vapors in the Headspaces of Single-Shell Waste Tanks

    Energy Technology Data Exchange (ETDEWEB)

    Stock, Leon M.; Huckaby, James L.

    2000-10-31

    This report summarizes data on the organic vapors in the single-shell high level radioactive waste tanks at the Hanford site to support a forthcoming toxicological study. All data were obtained from the Tank Characterization Database (PNNL 1999). The TCD contains virtually all the available tank headspace characterization data from 1992 to the present, and includes data for 109 different single-shell waste tanks. Each single-shell tank farm and all major waste types are represented. Descriptions of the sampling and analysis methods have been given elsewhere (Huckaby et al. 1995, Huckaby et al. 1996), and references for specific data are available in the TCD. This is a revision of a report with the same title issued on March 1, 2000 (Stock and Huckaby 2000).

  9. The DICE calibration project: design, characterization, and first results

    CERN Document Server

    Regnault, N; Schahmanèche, K; Guillou, L Le; Antilogus, P; Astier, P; Barrelet, E; Betoule, M; Bongard, S; Cuillandre, J -C; Juramy, C; Pain, R; Rocci, P -F; Tisserand, P; Villa, F

    2015-01-01

    We describe the design, operation, and first results of a photometric calibration project, called DICE (Direct Illumination Calibration Experiment), aiming at achieving precise instrumental calibration of optical telescopes. The heart of DICE is an illumination device composed of 24 narrow-spectrum, high-intensity, light-emitting diodes (LED) chosen to cover the ultraviolet-to-near-infrared spectral range. It implements a point-like source placed at a finite distance from the telescope entrance pupil, yielding a flat field illumination that covers the entire field of view of the imager. The purpose of this system is to perform a lightweight routine monitoring of the imager passbands with a precision better than 5 per-mil on the relative passband normalisations and about 3{\\AA} on the filter cutoff positions. The light source is calibrated on a spectrophotometric bench. As our fundamental metrology standard, we use a photodiode calibrated at NIST. The radiant intensity of each beam is mapped, and spectra are m...

  10. Hydrologic characterization of four cores from the Geysers Coring Project

    Energy Technology Data Exchange (ETDEWEB)

    Persoff, P. [Lawrence Berkeley National Lab., CA (United States); Hulen, J.B. [Univ. of Utah, Salt Lake City, UT (United States). Earth Sciences and Resources Institute

    1996-01-01

    Results of hydrologic tests on 4 representative core plugs from Geysers Coring Project drill hole SB-15-D were related to mineralogy and texture. Permeability measurements were made on 3 plugs from caprock and one plug from the steam reservoir. Late-stage microfractures present in 2 of the plugs contributed to greater permeability, but the values for the 2 other plugs indicate a typical matrix permeability of 1 to 2 {times} 10{sup {minus}21}m{sup 2}. Klinkenberg slip factor b for these plugs is generally consistent with the inverse relation between slip factor and permeability observed by Jones (1972) for plugs of much more permeable material. The caprock and reservoir samples are nearly identical metagraywackes with slight mineralogical differences which appear to have little effect on hydrology. The late stage microfractures are suspected of being artifacts. The capillary pressure curves for 3 cores are fit by power-law relations which can be used to estimate relative permeability curves for the matrix rocks.

  11. Yucca Mountain Site Characterization Project bibliography, 1992--1994. Supplement 4

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-06-01

    Following a reorganization of the Office of Civilian Radioactive Waste Management in 1990, the Yucca Mountain Project was renamed Yucca Mountain Site Characterization Project. The title of this bibliography was also changed to Yucca Mountain Site Characterization Project Bibliography. Prior to August 5, 1988, this project was called the Nevada Nuclear Waste Storage Investigations. This bibliography contains information on this ongoing project that was added to the Department of Energy`s Energy Science and Technology Database from January 1, 1992, through December 31, 1993. The bibliography is categorized by principal project participating organization. Participant-sponsored subcontractor reports, papers, and articles are included in the sponsoring organization`s list. Another section contains information about publications on the Energy Science and Technology Database that were not sponsored by the project but have some relevance to it. Earlier information on this project can be found in the first bibliography DOE/TIC-3406, which covers 1977--1985, and its three supplements DOE/OSTI-3406(Suppl.1), DOE/OSTI-3406(Suppl.2), and DOE/OSTI-3406(Suppl.3), which cover information obtained during 1986--1987, 1988--1989, and 1990--1991, respectively. All entries in the bibliographies are searchable online on the NNW database file. This file can be accessed through the Integrated Technical Information System (ITIS) of the US Department of Energy (DOE).

  12. Los Alamos National Laboratory Yucca Mountain Site Characterization Project 1994 quality program status report

    Energy Technology Data Exchange (ETDEWEB)

    Bolivar, S.L.

    1996-03-01

    This status report is for calendar year 1994. It summarizes the annual activities and accomplishments of the Los Alamos National Laboratory Yucca Mountain Site Characterization Project (YMP or Project) quality assurance program. By identifying the accomplishments of the quality program, a baseline is established that will assist in decision making, improve administrative controls and predictability, and allow us to annually identify adverse trends and to evaluate improvements. This is the fourth annual status report.

  13. Comparative analysis of headspace volatiles of Chinese Rosa rugosa.

    Science.gov (United States)

    Feng, Li-Guo; Chen, Chen; Sheng, Li-Xia; Liu, Ping; Tao, Jun; Su, Jia-Le; Zhao, Lan-Yong

    2010-11-16

    The floral headspace compounds of Chinese Rosa rugosa germplasms that were isolated by an automated headspace sampler with built-in trap, and followed by gas chromatography-mass spectrometry for identification and quantification. Up to 33 volatile compounds were identified from the 23 rose germplasms, including nine alcohols, five esters, three alkanes, 10 terpenes, three aldehydes, two ketones, and one ether. The main floral components identified were 2-phenylethanol, β-citronellol, ethanol, and n-hexane. 'xizi', 'miaofengshan', 'xiangciguo', and 'tangbai' contained the highest amounts of 2-phenylethanol at 84.66 μg·g⁻¹, β-citronellol at 70.98 μg·g⁻¹, ethanol at 83.87 μg·g⁻¹, and n-hexane at 18.23 μg·g⁻¹, respectively. 'Rongchengyesheng', 'tanghong', 'xizi', 'miaofengshan', and 'baizizhi' could be considered good materials for extracting rose oil and breeding new cultivars.

  14. Volatile release from aqueous solutions under dynamic headspace dilution conditions.

    Science.gov (United States)

    Marin, M; Baek, I; Taylor, A J

    1999-11-01

    Static equilibrium was established between the gas phase (headspace) and an unstirred aqueous phase in a sealed vessel. The headspace was then diluted with air to mimic the situation when a container of food is opened and the volatiles are diluted by the surrounding air. Because this first volatile signal can influence overall flavor perception, the parameters controlling volatile release under these conditions are of interest. A mechanistic model was developed and validated experimentally. Release of compounds depended on the air-water partition coefficient (K(aw)) and the mass transport in both phases. For compounds with K(aw) values 10(-)(3), mass transport in the gas phase became significant and the Reynolds number played a role. Because release from packaged foods occurs at low Reynolds numbers, whereas most experiments are conducted at medium to high Reynolds numbers, the experimentally defined profile may not reflect the real situation.

  15. Technology projects for characterization--monitoring of volatile organic compounds (VOCs)

    Energy Technology Data Exchange (ETDEWEB)

    Junk, G.A.; Haas, W.J. Jr.

    1992-07-01

    One hundred thirty technology project titles related to the characterization of volatile organic compounds (VOCs) at an arid site are listed alphabetically by first contact person in a master compilation that includes phone numbers, addresses, keywords, and short descriptions. Separate tables are presented for 62 field-demonstrated, 36 laboratory-demonstrated, and 35 developing technology projects. The technology projects in each of these three categories are also prioritized in separate summary tables. Additional tables are presented for a number of other categorizations of the technology projects: In Situ; Fiberoptic; Mass Spectrometer; Optical Spectroscopy; Raman or SERS; Ion Mobility or Acoustic; Associated; and Commercial. Four lists of contact person names are provided so details concerning the projects that deal with sampling, and VOCs in gases, waters, and soils (sediments) can be obtained. Finally, seven wide-ranging conclusions based on observations and experiences during this work are presented.

  16. A short review of headspace extraction and ultrasonic solvent extraction for honey volatiles fingerprinting

    OpenAIRE

    Jerković, I.; Marijanović, Z.

    2009-01-01

    Honey volatiles exhibit a potential role in distinguishing honeys as a function of botanical origin, but heating of honey generates artefacts such as compounds of Strecker degradation and Maillard reaction products. This short review is focused on the most recently applied methods for honey volatiles fingerprinting (without generation of thermal artefacts): headspace extraction (dynamic headspace extraction (DHE), headspace solid-phase microextraction (HS-SPME)) and ultrasonic solvent extract...

  17. K Basin Sandfilter Backwash Line Characterization Project and Analytical Results for Campaign 24

    Energy Technology Data Exchange (ETDEWEB)

    STEEN, F.H.

    1999-12-08

    Sample 203KWBMF was taken from the K West Sandfilter Backwash Pit on November 4, 1999 and received by 2224 Laboratory on November 4, 1999. Analyses were performed on sample 203KWBMF in accordance with ''Letter of Instruction for K Basins sandfilter Backwash Line Samples'' (LOI) in support of the K Basin Sandfilter Backwash Line Characterization Project.

  18. K Basin sandfilter backwash line characterization project, analytical results for Campaign 20

    Energy Technology Data Exchange (ETDEWEB)

    STEEN, F.H.

    1999-08-12

    Sample 112KWBMF was taken from the K West Sandfilter Backwash Pit on June 1, 1999, and received by 222-S Laboratory on June 2,1999. Analyses were performed on sample 112KWBMF in accordance with Letter of Instruction for K Basins Sandfilter Backwash Line Samples (LOI) in support of the K Basin Sandfilter Backwash Line Characterization Project.

  19. K Basin Sandfilter Backwash Line Characterization Project Analytical Results for Campaign 25

    Energy Technology Data Exchange (ETDEWEB)

    STEEN, F.H.

    2000-03-22

    Sample 023KWBMF was taken from the K West Sandfilter Backwash Pit on February 10, 2000 and received by 222-S Laboratory on February 11, 2000. Analyses were performed on sample 023KWBMF in accordance with ''Letter of Instruction for K Basins Sandfilter Backwash Line Samples'' (LOI) in support of the K Basin Sandfilter Backwash Line Characterization Project.

  20. A characterization of weak (semi-)projectivity for commutative C*-algebras

    CERN Document Server

    Enders, Dominic

    2011-01-01

    We show that the spectrum X of a weakly semiprojective, commutative C*-algebra C(X) is at most one dimensional. This completes the work of S{\\o}rensen and Thiel on the characterization of weak (semi-)projectivity for commutative C*-algebras.

  1. Analysis of Volatile Compounds from Solanumbetaceum Cav. Fruits from Panama by Head-Space Micro Extraction

    Directory of Open Access Journals (Sweden)

    Armando A. Durant

    2013-01-01

    Full Text Available The characterization of the volatile compounds of two varieties of Solanum betaceum Cav. by means of headspace solid-phase microextraction (HS-SPME coupled with gas chromatography-mass spectrometry ( GC-MS i s presented. The HS-SPME method for extraction of the volatiles compounds was optimized by using a 2 3 central composite design. Maximum extraction of volatile compounds was achieved by using a divinylbenzene-carboxen-polydimethylsiloxane (DVB/CAR/PDMS fiber, extraction temperature 76° C, incubation time 44 min, and extraction time of 46 min. The main types of compounds detected in both varieties are terpenoids, followed by aromatics, esters, and aldehydes. Golden-yellow cultivars contained higher levels of esters and terpenes, while the reddish-purple variety contained a significant amount of aromatic compounds. The data structure of the chemical information obtained as well as the relationship between variables was evaluated by means of principal component analysis and cluster analysis.

  2. Area 5 Site Characterization Project: Report of hydraulic property analysis through August 1993

    Energy Technology Data Exchange (ETDEWEB)

    Estrella, R.; Tyler, S.; Chapman, J.; Miller, M.

    1993-12-01

    The Area 5 Site Characterization Project is designed to determine the suitability of the Radioactive Waste Management Site (RWMS) for disposal of low-level waste (LLW), mixed waste (MW) and transuranic waste (TRU). The Desert Research Institute (DRI) has supported the Area 5 Site Characterization Project for the US Department of Energy, Nevada Operations Office (DOE/NV), Environmental Restoration and Waste Management Division (ERWM), Waste Operations Branch (WOB). The purpose of DRI`s Area 5 Site Characterization project is to characterize important properties of the upper vadose zone which influence infiltration and redistribution of water and transport of solutes as well as to characterize the water quality and hydrologic conditions of the uppermost aquifer. This report describes methods and presents a summary of all data and results from laboratory physical and chemical testing from Pilot Wells and Science Trench borehole samples through August 1993. DRI laboratories performed soil water content, soil water potential, soil bulk density, soil water extract isotope analyses and soil water chemistry analyses.

  3. Sandia National Laboratories site-wide hydrogeologic characterization project calendar year 1992 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Crowson, D.; Gibson, J.D.; Haase, C.S.; Holt, R.; Hyndman, D.; Krumhansl, J.; Lauffer, F.; McCord, J.P.; McCord, J.T.; Neel, D. [and others

    1993-10-01

    The Sandia National Laboratories, New Mexico (SNL/NM) Site-Wide Hydrogeologic Characterization (SWHC) project has been implemented as part of the SNL/NM Environmental Restoration (ER) Program to develop the regional hydrogeologic framework and baseline for the approximately 100 mi of Kirtland Air Force Base (KAFB) and adjacent withdrawn public lands upon which SNL/NM has performed research and development activities. Additionally, the SWHC project will investigate and characterize generic hydrogeologic issues associated with the 172 ER sites owned by SNL/NM across its facilities on KAFB. As called for in the Hazardous and Solid Waste Amendments (HSWA) to the Resource Conservation and Recovery Act (RCRA) Part B permit agreement between the U.S. Environmental Protection Agency (EPA) as the permitter and the U.S. Department of Energy (DOE) and SNL/NM as the permittees, an annual report is to be prepared by the SWHC project team. This document serves two primary purposes: (1) to identify and describe the conceptual framework for the hydrogeologic system underlying SNL/NM and (2) to describe characterization activities undertaken in the preceding year that add to our understanding (reduce our uncertainties) regarding the conceptual and quantitative hydrogeologic framework. This SWHC project annual report focuses primarily on purpose 1, providing a summary description of the current {open_quotes}state of knowledge{close_quotes} of the Sandia National Laboratories/Kirtland Air Force Base (SNL/KAFB) hydrogeologic setting.

  4. Large Area Projection Microstereolithography: Characterization and Optimization of 3D Printing Parameters

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Melissa R. [Ohlone College, Fremont, CA (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Moran, Bryan [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bekker, Logan [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dudukovic, Nikola [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-08-12

    Large Area Projection Microstereolithography (LAPμSL) is a new technology that allows the additive manufacture of parts that have feature sizes spanning from centimeters to tens of microns. Knowing the accuracy of builds from a system like this is a crucial step in development. This project explored the capabilities of the second and newest LAPμSL system that was built by comparing the features of actual builds to the desired structures. The system was then characterized in order to achieve the best results. The photo polymeric resins that were used were Autodesk PR48 and HDDA. Build parameters for Autodesk PR48 were found that allowed the prints to progress while using the full capacity of the system to print quality parts in a relatively short amount of time. One of the larger prints in particular had a print time that was nearly eighteen times faster than it would have been had printed in the first LAPμSL system. The characterization of HDDA resin helped the understanding that the flux of the light projected into the resin also affected the quality of the builds, rather than just the dose of light given. Future work for this project includes exploring the use of other resins in the LAPμSL systems, exploring the use of Raman Spectroscopy to analyze builds, and completing the characterization of the LAPμSL system.

  5. Global Threat Reduction Initiative Fuel Thermo-Physical Characterization Project: Sample Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    Casella, Amanda J.; Pereira, Mario M.; Steen, Franciska H.

    2013-01-01

    This sample management plan provides guidelines for sectioning, preparation, acceptance criteria, analytical path, and end-of-life disposal for the fuel element segments utilized in the Global Threat Reduction Initiative (GTRI), Fuel Thermo-Physical Characterization Project. The Fuel Thermo-Physical Characterization Project is tasked with analysis of irradiated Low Enriched Uranium (LEU) Molybdenum (U-Mo) fuel element samples to support the GTRI conversion program. Sample analysis may include optical microscopy (OM), scanning electron microscopy (SEM) fuel-surface interface analysis, gas pycnometry (density) measurements, laser flash analysis (LFA), differential scanning calorimetry (DSC), thermogravimetry and differential thermal analysis with mass spectroscopy (TG /DTA-MS), Inductively Coupled Plasma Spectrophotometry (ICP), alpha spectroscopy, and Thermal Ionization Mass Spectroscopy (TIMS). The project will utilize existing Radiochemical Processing Laboratory (RPL) operating, technical, and administrative procedures for sample receipt, processing, and analyses. Test instructions (TIs), which are documents used to provide specific details regarding the implementation of an existing RPL approved technical or operational procedure, will also be used to communicate to staff project specific parameters requested by the Principal Investigator (PI). TIs will be developed, reviewed, and issued in accordance with the latest revision of the RPL-PLN-700, RPL Operations Plan. Additionally, the PI must approve all project test instructions and red-line changes to test instructions.

  6. Headspace-gas chromatographic fingerprints to discriminate and classify counterfeit medicines.

    Science.gov (United States)

    Custers, D; Canfyn, M; Courselle, P; De Beer, J O; Apers, S; Deconinck, E

    2014-06-01

    Counterfeit medicines are a global threat to public health. These pharmaceuticals are not subjected to quality control and therefore their safety, quality and efficacy cannot be guaranteed. Today, the safety evaluation of counterfeit medicines is mainly based on the identification and quantification of the active substances present. However, the analysis of potential toxic secondary components, like residual solvents, becomes more important. Assessment of residual solvent content and chemometric analysis of fingerprints might be useful in the discrimination between genuine and counterfeit pharmaceuticals. Moreover, the fingerprint approach might also contribute in the evaluation of the health risks different types of counterfeit medicines pose. In this study a number of genuine and counterfeit Viagra(®) and Cialis(®) samples were analyzed for residual solvent content using headspace-GC-MS. The obtained chromatograms were used as fingerprints and analyzed using different chemometric techniques: Principal Component Analysis, Projection Pursuit, Classification and Regression Trees and Soft Independent Modelling of Class Analogy. It was tested whether these techniques can distinguish genuine pharmaceuticals from counterfeit ones and if distinct types of counterfeits could be differentiated based on health risks. This chemometric analysis showed that for both data sets PCA clearly discriminated between genuine and counterfeit drugs, and SIMCA generated the best predictive models. This technique not only resulted in a 100% correct classification rate for the discrimination between genuine and counterfeit medicines, the classification of the counterfeit samples was also superior compared to CART. This study shows that chemometric analysis of headspace-GC impurity fingerprints allows to distinguish between genuine and counterfeit medicines and to differentiate between groups of counterfeit products based on the public health risks they pose. Copyright © 2014 Elsevier B

  7. Geotechnical characterization of the North Ramp of the Exploratory Studies Facility: Yucca Mountain Site Characterization Project. Volume 1, Data summary

    Energy Technology Data Exchange (ETDEWEB)

    Brechtel, C.E.; Lin, Ming; Martin, E. [Agapito Associates, Inc., Grand Junction, CO (United States); Kessel, D.S. [Sandia National Labs., Albuquerque, NM (United States)

    1995-05-01

    This report presents the results of geological and geotechnical characterization of the Miocene volcanic tuff rocks of the Timber Mountain and Paintbrush groups that the tunnel boring machine will encounter during excavation of the Exploratory Studies Facility (ESF) North Ramp. The is being constructed by the DOE as part of the Yucca Mountain Project site characterization activities. The purpose of these activities is to evaluate the feasibility of locating a potential high-level nuclear waste repository on lands adjacent to the Nevada Test Site, Nye County, Nevada. This report was prepared as part of the Soil and Rock Properties Studies in accordance with the 8.3.1.14.2 Study Plan. This report is volume 1 of the data summary.

  8. Effects of headspace fraction and aqueous alkalinity on subcritical hydrothermal gasification of cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Dolan, Ryan; Yin, Sudong; Tan, Zhongchao [Department of Mechanical and Manufacturing Engineering, Centre for Environmental Engineering Research and Education, Schulich School of Engineering, University of Calgary, 2500 University Dr. N.W. Calgary, AB (Canada)

    2010-07-15

    In order to better understand the pathways of hydrothermal gasification of cellulose, the effect of headspace fraction and alkalinity on the hydrothermal gasification of cellulose has been studied at 315 C in the presence of Pt/Al{sub 2}O{sub 3} as catalyst. It was found that regardless of alkalinity the headspace fraction had a large impact on gasification yield, with larger headspace fractions resulting in considerably more gas product. Without the addition of sodium carbonate, the effect of headspace fraction became more pronounced, with gas increasing by approximately a factor of forty from the lowest to highest headspace fraction. On the other hand, for the same residence time the addition of sodium carbonate co-catalyst dampened the magnitude of the effect, to a factor of 2.5 and 1.5, for 50 and 100 mM sodium carbonate solutions, respectively. These results indicated that the headspace fraction affected the phase behaviour, and that this altered the pathway of the cellulose decomposition. While furfural alcohol was the major product obtained with a 49% headspace fraction, it was effectively suppressed by using 78% or greater headspace fractions. Based on the effects of phase behaviour and previous literature, the reduced effect occurring upon the addition of sodium carbonate may relate to catalysis of the Lobry de-bruyn Van Eckenstein transform to produce lactic acid rather than intermediates proceeding through glycolaldehyde. (author)

  9. Bepaling van tetrachloor- en trichloorethyleen in olijfolie met behulp van headspace - gaschromatografie

    NARCIS (Netherlands)

    Roos, A.H.; Mazijk, van R.J.; Tuinstra, L.G.M.Th.

    1990-01-01

    De resultaten van de EEG headspace methode wijzen uit dat de herhaalbaarheid en nauwkeurigheid voldoende zijn om tetrachloor- en trichloorethyleen in olijfolie te bepalen tot een niveau van 0,01 mg/kg op produkt. De headspace techniek is door de eenvoudige procedure zeer geschikt voor routine analys

  10. DISSOLVED OXYGEN AND METHANE IN WATER BY A GC HEADSPACE EQUILIBRATION TECHNIQUE

    Science.gov (United States)

    An analytical procedure is described for the determination of dissolved oxygen and methane in groundwater samples. The method consists of generating a helium gas headspace in a water filled bottle, and analysis of the headspace by gas chromatography. Other permanent gases such as...

  11. Primary Polymer Aging Processes Identified from Weapon Headspace Chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, D M; Bazan, J M; Ithaca, J G

    2002-03-25

    A current focus of our weapon headspace sampling work is the interpretation of the volatile chemical signatures that we are collecting. To help validate our interpretation we have been developing a laboratory-based material aging capability to simulate material decomposition chemistries identified. Key to establishing this capability has been the development of an automated approach to process, analyze, and quantify arrays of material combinations as a function of time and temperature. Our initial approach involves monitoring the formation and migration of volatile compounds produced when a material decomposes. This approach is advantageous in that it is nondestructive and provides a direct comparison with our weapon headspace surveillance initiative. Nevertheless, this approach requires us to identify volatile material residue and decomposition byproducts that are not typically monitored and reported in material aging studies. Similar to our weapon monitoring method, our principle laboratory-based method involves static headspace collection by solid phase microextraction (SPME) followed by gas chromatography/mass spectrometry (GC/MS). SPME is a sorbent collection technique that is ideally suited for preconcentration and delivery of trace gas-phase compounds for analysis by GC. When combined with MS, detection limits are routinely in the low- and sub-ppb ranges, even for semivolatile and polar compounds. To automate this process we incorporated a robotic sample processor configured for SPME collection. The completed system will thermally process, sample, and analyze a material sample. Quantification of the instrument response is another process that has been integrated into the system. The current system screens low-milligram quantities of material for the formation or outgas of small compounds as initial indicators of chemical decomposition. This emerging capability offers us a new approach to identify and non-intrusively monitor decomposition mechanisms that are

  12. Multiple headspace-solid-phase microextraction: An application to quantification of mushroom volatiles

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Rosaria; Tedone, Laura; De Grazia, Selenia [Dipartimento Farmaco-chimico, University of Messina, viale Annunziata, 98168 Messina (Italy); Dugo, Paola [Dipartimento Farmaco-chimico, University of Messina, viale Annunziata, 98168 Messina (Italy); Centro Integrato di Ricerca (C.I.R.), Università Campus-Biomedico, Via Álvaro del Portillo, 21, 00128 Roma (Italy); Mondello, Luigi, E-mail: lmondello@unime.it [Dipartimento Farmaco-chimico, University of Messina, viale Annunziata, 98168 Messina (Italy); Centro Integrato di Ricerca (C.I.R.), Università Campus-Biomedico, Via Álvaro del Portillo, 21, 00128 Roma (Italy)

    2013-04-03

    Highlights: ► Multiple headspace extraction-solid phase microextraction (MHS-SPME) has been applied to the analysis of Agaricus bisporus. ► Mushroom flavor is characterized by the presence of compounds with a 8-carbon atoms skeleton. ► Formation of 8-carbon compounds involves a unique fungal biochemical pathway. ► The MHS-SPME allowed to determine quantitatively 5 target analytes of A. bisporus for the first time. -- Abstract: Multiple headspace-solid phase microextraction (MHS-SPME) followed by gas chromatography/mass spectrometry (GC–MS) and flame ionization detection (GC–FID) was applied to the identification and quantification of volatiles released by the mushroom Agaricus bisporus, also known as champignon. MHS-SPME allows to perform quantitative analysis of volatiles from solid matrices, free of matrix interferences. Samples analyzed were fresh mushrooms (chopped and homogenized) and mushroom-containing food dressings. 1-Octen-3-ol, 3-octanol, 3-octanone, 1-octen-3-one and benzaldehyde were common constituents of the samples analyzed. Method performance has been tested through the evaluation of limit of detection (LoD, range 0.033–0.078 ng), limit of quantification (LoQ, range 0.111–0.259 ng) and analyte recovery (92.3–108.5%). The results obtained showed quantitative differences among the samples, which can be attributed to critical factors, such as the degree of cell damage upon sample preparation, that are here discussed. Considerations on the mushrooms biochemistry and on the basic principles of MHS analysis are also presented.

  13. CACAO: A project for a laboratory for the production and characterization of thin radioactive layers

    Energy Technology Data Exchange (ETDEWEB)

    Bacri, C.O., E-mail: bacri@ipno.in2p3.f [Institut de Physique Nucleaire d' Orsay, 91406 Orsay Cedex, CNRS (UMR8608-IN2P3), Universite Paris-Sud (Paris XI) (France); Petitbon, V.; Pierre, S. [Institut de Physique Nucleaire d' Orsay, 91406 Orsay Cedex, CNRS (UMR8608-IN2P3), Universite Paris-Sud (Paris XI) (France)

    2010-02-11

    CACAO, Chimie des Actinides et Cibles radioActives a Orsay (actinide chemistry and radioactive targets at Orsay), is a project under construction that consists of the installation of a hot laboratory dedicated to the production and characterization of thin radioactive layers. The project aims to be a joint CNRS-CEA national laboratory to overcome difficulties related mainly to safety issues and to the lack of knowledge and potential manpower. The first goal is to fulfill, at least, the needs of the whole French community, and to be able to coordinate the different activities related to radioactive targets. For this purpose, itis important to be complementary to already existing international installations. Inside this framework, it will of course be possible to produce and/or characterize targets for other users.

  14. CACAO: A project for a laboratory for the production and characterization of thin radioactive layers

    Science.gov (United States)

    Bacri, C. O.; Petitbon, V.; Pierre, S.; Cacao Group

    2010-02-01

    CACAO, Chimie des Actinides et Cibles radioActives à Orsay (actinide chemistry and radioactive targets at Orsay), is a project under construction that consists of the installation of a hot laboratory dedicated to the production and characterization of thin radioactive layers. The project aims to be a joint CNRS-CEA national laboratory to overcome difficulties related mainly to safety issues and to the lack of knowledge and potential manpower. The first goal is to fulfill, at least, the needs of the whole French community, and to be able to coordinate the different activities related to radioactive targets. For this purpose, itis important to be complementary to already existing international installations. Inside this framework, it will of course be possible to produce and/or characterize targets for other users.

  15. Study of ultrasonic characterization and propagation in austenitic welds: The MOSAICS project

    Energy Technology Data Exchange (ETDEWEB)

    Chassignole, Bertrand, E-mail: bertrand.chassignole@edf.fr [EDF R and D, MMC department, Les Renardières, 77818 Moret sur Loing (France); Recolin, Patrick, E-mail: patrick.recolin@dcnsgroup.com [DCNS CESMAN, 44620 La montagne (France); Leymarie, Nicolas, E-mail: nicolas.leymarie@cea.fr [CEA LIST, 91191 Gif-sur-Yvette (France); Gueudré, Cécile, E-mail: cecile.gueudre@univ-amu.fr [LMA, Aix Marseille Université, CNRS, UPR 7051, F-13402 Marseille Cedex 20 (France); Guy, Philippe, E-mail: philippe.guy@insa-lyon.fr [INSA Lyon, LVA laboratory, 69621 Villeurbanne (France); Elbaz, Deborah, E-mail: deborah.elbaz@extende.com [Extende, 91400 Orsay (France)

    2015-03-31

    Regulatory requirements enforce a volumetric inspection of welded components of nuclear equipments. However, the multi-pass austenitic welds are characterized by anisotropic and heterogeneous structures which lead to numerous disturbances of the ultrasonic beam. The MOSAICS project supported by the ANR (French National Research Agency) aims at matching various approaches to improve the prediction of the ultrasonic testing in those welds. The first stage consists in characterizing the weld structure (determination of the columnar grain orientation and measurements of elastic constants and attenuation coefficients). The techniques of characterization provide input data for the modeling codes developed in another task of the project. For example, a 3D version of the finite elements code ATHENA is developed by EDF R and D to take into account anisotropic texture in any direction. Semi-analytical models included in CIVA software are also improved to better predict the ultrasonic propagation in highly anisotropic and heterogeneous structures. The last stage deals with modeling codes validation based on experimental inspections on representative mock-ups containing calibrated defects. The objective of this paper is to give an overview of the MOSAICS project and to present specific results illustrating the various tasks.

  16. Global Threat Reduction Initiative Fuel-Thermo-Physical Characterization Project Quality Assurance Plan

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Mario M.; Slonecker, Bruce D.

    2012-06-01

    The charter of the Fuel Thermo-Physical Characterization Project is to ready Pacific Northwest National Laboratory (PNNL) facilities and processes for the receipt of unirradiated and irradiated low enriched uranium (LEU) molybdenum (U-Mo) fuel element samples, and to perform analysis to support the Global Threat Reduction Initiative conversion program. PNNL’s support for the program will include the establishment of post-irradiation examination processes, including thermo-physical properties, unique to the U.S. Department of Energy laboratories. These processes will ultimately support the submission of the base fuel qualification (BFQ) to the U.S. Nuclear Regulatory Commission (NRC) and revisions to High Performance Research Reactor Safety Analysis Reports to enable conversion from highly enriched uranium to LEU fuel. This quality assurance plan (QAP) provides the quality assurance requirements and processes that support the NRC BFQ. This QAP is designed to be used by project staff, and prescribes the required management control elements that are to be met and how they are implemented. Additional controls are captured in Fuel Thermo-Physical Characterization Project plans, existing procedures, and procedures to be developed that provide supplemental information on how work is conducted on the project.

  17. The Salvá-Sinobas project: Characterization of Iberian climate during the 1750-1850 period.

    Science.gov (United States)

    García-Herrera, R.

    2009-09-01

    This poster describes the recently started Salvá-Sinobas project, which is funded by the Spanish Ministry of Environment for the period 2009-2011. It includes research groups from different Spanish Universities: Complutense de Madrid, Extremadura, Almería, Barcelona, Murcia, Vigo, Pablo de Olavide and Zaragoza. The main aim of the project is the characterization of climate in Iberia during the period 1750-1850. The main steps that can be identified are: data recovery and abstraction, building of new documentary and natural proxies, regional modeling and data analysis. To increase the data availability for this period, new data sources will be used: - Early instrumental series will be recovered for several sites, including Barcelona, Madrid and Menorca. We expect to recover the longest observational series for Spain. - The complete collection of English logbooks sailing in the Mediterranean during the study period - Documentary proxies of extreme hydrological, precipitation and temperature events. - Tree ring series from unexplored species and areas. - New simulations from RCMs. All these series will be freely available at the end of the project from the project website http://www.salva-sinobas.uvigo.es. They will be used as the basis for different statistical and dynamical analysis. They will include: identification of temperature and precipitation extreme events, characterization of circulation patterns and the role of teleconnections along the study period, evaluation of the climate anomalies recorded during the Dalton minimum (1790-1820) and evaluation of health impacts.

  18. Comparative Analysis of Headspace Volatiles of Chinese Rosa rugosa

    Directory of Open Access Journals (Sweden)

    Lan-Yong Zhao

    2010-11-01

    Full Text Available The floral headspace compounds of Chinese Rosa rugosa germplasms that were isolated by an automated headspace sampler with built-in trap, and followed by gas chromatography-mass spectrometry for identification and quantification. Up to 33 volatile compounds were identified from the 23 rose germplasms, including nine alcohols, five esters, three alkanes, 10 terpenes, three aldehydes, two ketones, and one ether. The main floral components identified were 2-phenylethanol, β-citronellol, ethanol, and n-hexane. ‘xizi’, ‘miaofengshan’, ‘xiangciguo’, and ‘tangbai’ contained the highest amounts of 2-phenylethanol  at 84.66 μg·g-1, β-citronellol at 70.98 μg·g-1, ethanol at 83.87 μg·g-1, and n-hexane at 18.23 μg·g-1, respectively. ‘Rongchengyesheng’, ‘tanghong’, ‘xizi’, ‘miaofengshan’, and ‘baizizhi’ could be considered good materials for extracting rose oil and breeding new cultivars.

  19. Dynamic headspace time-extended helix liquid-phase microextraction.

    Science.gov (United States)

    Huang, Shih-Pin; Chen, Pai-Shan; Huang, Shang-Da

    2009-05-15

    Liquid-phase microextraction (LPME) has been proved to be a fast, inexpensive and effective sample pre-treatment technique for the analyses of pesticides and many other compounds. In this investigation, a new headspace microextraction technique, dynamic headspace time-extended helix liquid-phase microextraction (DHS-TEH-LPME), is presented. In this work, use of a solvent cooling system, permits the temperature of the extraction solvent to be lowered. Lowering the temperature of the extraction solvent not only reduces solvent loss but also extends the feasible extraction time, thereby improving extraction efficiency. Use of a larger volume of the solvent not only extends the feasible extraction time but also, after extraction, leaves a larger volume to be directly injected into the gas chromatography (GC) to increase extraction efficiency and instrument signal. The DHS-TEH-LPME technique was used to extract six organochlorine pesticides (OCPs) from 110ml water samples that had been spiked with the analytes at ng/l levels, and stirred for 60min. The proposed method attained enrichments up to 2121 fold. The effects of extraction solvent identity, sample agitation, extraction time, extraction temperature, and salt concentration on extraction performance were also investigated. The method detection limits (MDLs) varied from 0.2 to 25ng/l. The calibration curves were linear for at least 2 orders of magnitude with R(2)>==0.996. Relative recoveries in river water were more than 86%.

  20. Dynamic headspace liquid-phase microextraction of alcohols.

    Science.gov (United States)

    Saraji, Mohammad

    2005-01-07

    A method was developed using dynamic headspace liquid-phase microextraction and gas chromatography-mass spectrometry for extraction and determination of 9 alcohols from water samples. Four different solvents, hexyl acetate, n-octanol, o-xylene and n-decane were studied as extractants. The analytes were extracted using 0.8 microl of n-octanol from the headspace of a 2 ml sample solution. The effect of sampling volume, solvent volume, sample temperature, syringe plunger withdrawal rate and ionic strength of the solution on the extraction performance were studied. A semiautomated system including a variable speed stirring motor was used to ensure a uniform movement of syringe plunger through the barrel. The method provided a fairly good precision for all compounds (5.5-9.3%), except methanol (16.4%). Detection limits were found to be between 1 and 97 microg/l within an extraction time of approximately 9.5 min under GC-MS in full scan mode.

  1. Nevada Test Site Perspective on Characterization and Loading of Legacy Transuranic Drums Utilizing the Central Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    R.G. Lahoud; J. F. Norton; I. L. Siddoway; L. W. Griswold

    2006-01-01

    The Nevada Test Site (NTS) has successfully completed a multi-year effort to characterize and ship 1860 legacy transuranic (TRU) waste drums for disposal at the Waste Isolation Pilot Plant (WIPP), a permanent TRU disposal site. This has been a cooperative effort among the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), the U.S. Department of Energy, Carlsbad Field Office (DOE/CBFO), the NTS Management and Operations (M&O) contractor Bechtel Nevada (BN), and various contractors under the Central Characterization Project (CCP) umbrella. The success is due primarily to the diligence, perseverance, and hard work of each of the contractors, the DOE/CBFO, and NNSA/NSO, along with the support of the U.S. Department of Energy, Headquarters (DOE/HQ). This paper presents, from an NTS perspective, the challenges and successes of utilizing the CCP for obtaining a certified characterization program, sharing responsibilities for characterization, data validation, and loading of TRU waste with BN to achieve disposal at WIPP from a Small Quantity Site (SQS) such as the NTS. The challenges in this effort arose from two general sources. First, the arrangement of DOE/CBFO contractors under the CCP performing work and certifying waste at the NTS within a Hazard Category 2 (HazCat 2) non-reactor nuclear facility operated by BN, presented difficult challenges. The nuclear safety authorization basis, safety liability and responsibility, conduct of operations, allocation and scheduling of resources, and other issues were particularly demanding. The program-level and field coordination needed for the closely interrelated characterization tasks was extensive and required considerable effort by all parties. The second source of challenge was the legacy waste itself. None of the waste was generated at the NTS. The waste was generated at Lawrence Livermore National Laboratory (LLNL), Lawrence Berkeley Laboratory (LBL), Lynchburg, Rocky Flats

  2. Comparison between dynamic headspace and headspace solid-phase microextraction for gas chromatography of BTEX in urine.

    Science.gov (United States)

    Brcić Karaconji, Irena; Skender, Ljiljana

    2007-12-01

    The aim of this study was to compare two extraction procedures: dynamic headspace-purge and trap (PT) and headspace solid-phase microextraction (HS-SPME) for gas chromatographic determination of benzene, toluene, ethylbenzene, and isomeric xylenes (BTEX) in urine with photoionization (PID) and mass spectrometric (MS) detection, respectively. Both methods showed linearity in the range of interest [(50-2000) ng L-1], good accuracy (80% to 100%), and repeatability (RSD< or =11%). Detection limits were in the low ng L-1 level for both methods, although slightly greater sensitivity was found for the PT method. In comparison with PT, HS-SPME was simpler and required less time for analysis. Although the analytical features of both examined methods are appropriate for biomonitoring of environmental exposure to BTEX, only the HS-SPME-GC-MS method is recommended for routine analysis of BTEX in urine. The method was applied for the quantitative analysis of BTEX in urine samples collected from non-smokers (n=10) and smokers (n=10).

  3. Innovation in youth mental health services in Australia: common characteristics across the first headspace centres.

    Science.gov (United States)

    Rickwood, Debra; Van Dyke, Nina; Telford, Nic

    2015-02-01

    headspace centres comprise a significant innovation in community-based youth mental health service delivery in Australia. This paper examines the service activity of the first headspace centres to determine common and unique practice characteristics across headspace centres in this new approach to mental health service delivery. Data come from quarterly progress reports provided by the first 30 headspace centres during the 2010-2011 financial year. The information from 120 reports was analysed qualitatively using thematic analysis techniques to determine the types of activities reported by centres against key performance indicators. The main finding was the large number and wide range of centre activity. This heterogeneity may be explained in part by the diversity of communities across Australia and the importance that headspace places on addressing the specific needs of the local community as well as drawing upon the existing capacity that is available within a community. The most common activities were community engagement, building local partnerships and providing a youth friendly environment. There was a particularly strong focus by the majority of centres on establishing and supporting a Youth Reference Group to guide centre development and implementation. The progressive upscaling of headspace centres across Australia provides a unique opportunity to observe how a significant reorientation in health service delivery is implemented in practice to meet the needs of diverse communities. Further investigation of the headspace experience will provide critical lessons for other countries investing in new approaches to youth mental health. © 2013 Wiley Publishing Asia Pty Ltd.

  4. Characterizing Mystery Cell Lines: Student-driven Research Projects in an Undergraduate Neuroscience Laboratory Course

    Science.gov (United States)

    Lemons, Michele L.

    2012-01-01

    Inquiry-based projects promote discovery and retention of key concepts, increase student engagement, and stimulate interest in research. Described here are a series of lab exercises within an undergraduate upper level neuroscience course that train students to design, execute and analyze their own hypothesis-driven research project. Prior to developing their own projects, students learn several research techniques including aseptic cell culture, cell line maintenance, immunocytochemistry and fluorescent microscopy. Working in groups, students choose how to use these techniques to characterize and identify a “mystery” cell line. Each lab group is given a unique cell line with either a neural, astrocyte, or Schwann cell origin. Working together, students plan and execute experiments to determine the cellular origin and other unique characteristics of their mystery cell line. Students generate testable hypotheses, design interpretable experiments, generate and analyze data, and report their findings in both oral and written formats. Students receive instructor and peer feedback throughout the entire project. In summary, these labs train students the process of scientific research. This series of lab exercises received very strong positive feedback from the students. Reflections on student feedback and plans for future improvements are discussed. PMID:23504583

  5. Characterizing Mystery Cell Lines: Student-driven Research Projects in an Undergraduate Neuroscience Laboratory Course.

    Science.gov (United States)

    Lemons, Michele L

    2012-01-01

    Inquiry-based projects promote discovery and retention of key concepts, increase student engagement, and stimulate interest in research. Described here are a series of lab exercises within an undergraduate upper level neuroscience course that train students to design, execute and analyze their own hypothesis-driven research project. Prior to developing their own projects, students learn several research techniques including aseptic cell culture, cell line maintenance, immunocytochemistry and fluorescent microscopy. Working in groups, students choose how to use these techniques to characterize and identify a "mystery" cell line. Each lab group is given a unique cell line with either a neural, astrocyte, or Schwann cell origin. Working together, students plan and execute experiments to determine the cellular origin and other unique characteristics of their mystery cell line. Students generate testable hypotheses, design interpretable experiments, generate and analyze data, and report their findings in both oral and written formats. Students receive instructor and peer feedback throughout the entire project. In summary, these labs train students the process of scientific research. This series of lab exercises received very strong positive feedback from the students. Reflections on student feedback and plans for future improvements are discussed.

  6. Technical data base quarterly report, April--June 1992; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-09-01

    The acquisition and development of technical data are activities that provide the information base from which the Yucca mountain Site will be characterized and may P-ventually be licensed as a high-level waste repository. The Project Technical Data Base (TDB) is the repository for the regional and site-specific technical data required in intermediate and license application analyses and models. The TDB Quarterly Report provides the mechanism for identifying technical data currently available from the Project TDB. Due to the variety of scientific information generated by YMP activities, the Project TDB consists of three components, each designed to store specific types of data. The Site and Engineering Properties Data Base (SEPDB) maintains technical data best stored in a tabular format. The Geographic Nodal Information Study and Evaluation System (GENISES), which is the Geographic Information System (GIS) component of the Project TDB, maintains spatial or map-like data. The Geologic and Engineering Materials Bibliography of Chemical Species (GEMBOCHS) data base maintains thermodynamic/geochemical data needed to support geochemical reaction models involving the waste package and repository geochemical environment. Each of these data bases are addressed independently within the TDB Quarterly Report.

  7. In Situ Site Characterization Technologies Demonstrated at the INEEL in Decommissioning Projects

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Kelly Clyde; Meservey, Richard Harlan; Whitmill, Larry Joseph

    1999-04-01

    The United States Department of Energy (DOE)continually seeks safer, more cost-effective, and better performing technologies for decontamination and decommissioning (D&D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE Federal Energy Technology Center (FETC) sponsors Large Scale Demonstration and Deployment Projects (LSDDPs) which are conducted at various DOE sites. The Idaho National Engineering and Environmental Laboratory (INEEL) is one of the DOE sites for demonstration of these newa and improved technologies. The INEEL needs statement defines specific needs or problems for their D&D program. One of the needs identified at the INEEL was for new or improved site characterization technologies. A variety of in-situ site characterization technologies have been demonstrated through the INEEL LSDDP. These technologies provide a safer means of characterization, improved documentation, real-time information, improved D&D schedules, and reduction in costs and radiation exposures to workers. These technologies have provided vast improvements to the D&D site characterizations. Some of these technologies include: • The Global Positioning Radiometric Scanner System for large-area, surface gamma radiation surveys • Remote underwater characterization system• Identifying heavy metals in painted surfaces and determining the alloy composition in metallic material • In-Situ Object Counting System for free release • Real-time radiological data acquisition with the Surveillance and Measurement’s sodium iodide detector • Electromagnetic radiography to locate contaminated soils. Historically, site characterization has been a slow, costly, and tedious process. However, through these demonstrations, new technologies have provided more accurate data, real-time information, and enhanced site characterization documentation. In addition, a safer work environment has been established as a result of decreasing the worker’s time

  8. Utilizing Isolation, Purification, and Characterization of Enzymes as Project-Oriented Labs for Undergraduate Biochemistry

    Science.gov (United States)

    Deal, S. Todd; Hurst, Michael O.

    1997-02-01

    Senior-level biochemistry labs are mostly verification-type laboratories with little chance for exploration. We have developed a project-based biochemistry laboratory which gives them a chance to carry out a major biochemistry project. In the first quarter it is based on the purification of the enzyme lysozyme. The students are given some basic information, and then work out the details of their own procedures, make up their own solutions, and work at their own pace. Students use centrifugation, ion-exchange chromatography, spectral enzyme assays, and SDS-gel electrophoresis to purify and characterize the protein. In the second quarter students are given acid phosphatase and the basic assay for the enzyme, and then develop and carry out a method for determining the kinetic parameters of the enzyme. These experiments continue the development of laboratory independence of the students which steadily progresses in most curriculum

  9. Characterizing the emissivity of materials under dynamic compression (final report for LDRD project 79877).

    Energy Technology Data Exchange (ETDEWEB)

    Dolan, Daniel H.

    2007-10-01

    Temperature measurements are crucial to equation of state development, but difficult to perform reliably. In the case of infrared pyrometry, a large uncertainty comes from the fact that sample emissivity (the deviation from a blackbody) is unknown. In this project, a method for characterizing the emissivity of shocked materials was developed. By coupling infrared radiation from the National Synchrotron Light Source to a gas gun system, broad spectrum emissivity changes were studied to a peak stress of 8 GPa. Emissivity measurements were performed on standard metals (Al, Cr, Cu, and Pt) as well as a high emissivity coating developed at Sandia.

  10. Test and characterization of multigap resistive plate chambers for the EEE project

    CERN Document Server

    Bossini, E

    2016-01-01

    The Extreme Energy Events project is based on the deployment of cosmic-ray telescopes in Italian high schools with the active contribution of students and teachers. Each telescope is made by three Multigap Resistive Plate Chambers readout by strips. With around 50 telescopes already built and others under construction, specific systems to test and characterize the chambers are needed. In this article I will present a flexible and software-configurable solution to perform chamber efficiency studies with a set of scintillators and hardware to automatically scan detector strips to identify electrical issues. Both systems can provide accurate information but at the same time they can be easily operated by students.

  11. Test and characterization of multigap resistive plate chambers for the EEE project

    Science.gov (United States)

    Bossini, E.; EEE Collaboration

    2016-03-01

    The Extreme Energy Events project is based on the deployment of cosmic-ray telescopes in Italian high schools with the active contribution of students and teachers. Each telescope is made by three Multigap Resistive Plate Chambers readout by strips. With around 50 telescopes already built and others under construction, specific systems to test and characterize the chambers are needed. In this article I will present a flexible and software-configurable solution to perform chamber efficiency studies with a set of scintillators and hardware to automatically scan detector strips to identify electrical issues. Both systems can provide accurate information but at the same time they can be easily operated by students.

  12. Review of Mass Spectrometry Data from Waste Tank Headspace Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Sklarew, Debbie S.; Mitroshkov, Alexandre V.

    2006-02-28

    Numerous analytes have been categorized as tentatively identified compounds (TICs) in air samples from the headspaces of the Hanford Site high-level radioactive waste tanks. The tentative identification of these compounds was based mainly on the agreement between the observed mass spectra and a library of published mass spectra with consideration given to the gas chromatographic conditions and retention times. Many of the TICs were found in a limited number of tanks, were identified by only one laboratory or by one method, and/or were thought to be unlikely components of the waste or its degradation products. Consequently, the mass spectra of selected analytes have been reviewed to determine if their tentative identifications were correct. From our current review of 49 TICs, we found 25 that were misidentified and recommend that 54 of the associated results be flagged as suspect and 22 of the associated results be assigned a different compound name.

  13. Solvent desorption dynamic headspace sampling of fermented dairy product volatiles.

    Science.gov (United States)

    Rankin, S A

    2001-01-01

    A method was developed based on solvent desorption dynamic headspace analysis for the identification and relative quantification of volatiles significant to the study of fermented dairy product aroma. Descriptions of applications of this method are presented including the measurement of diacetyl and acetoin in fermented milk, the evaluation of volatile-hydrocolloid interactions in dairy-based matrices, and the identification of volatiles in cheeses for canonical discriminative analysis. Advantages of this method include rapid analysis, minimal equipment investment, and the ability to analyze samples with traditional GC split/splitless inlet systems. Limitations of this method are that the sample must be in the liquid state and the inherent analytical limitation to those compounds that do not coelute with the solvent or solvent impurity peaks.

  14. Central and Eastern United States (CEUS) Seismic Source Characterization (SSC) for Nuclear Facilities Project

    Energy Technology Data Exchange (ETDEWEB)

    Kevin J. Coppersmith; Lawrence A. Salomone; Chris W. Fuller; Laura L. Glaser; Kathryn L. Hanson; Ross D. Hartleb; William R. Lettis; Scott C. Lindvall; Stephen M. McDuffie; Robin K. McGuire; Gerry L. Stirewalt; Gabriel R. Toro; Robert R. Youngs; David L. Slayter; Serkan B. Bozkurt; Randolph J. Cumbest; Valentina Montaldo Falero; Roseanne C. Perman' Allison M. Shumway; Frank H. Syms; Martitia (Tish) P. Tuttle

    2012-01-31

    This report describes a new seismic source characterization (SSC) model for the Central and Eastern United States (CEUS). It will replace the Seismic Hazard Methodology for the Central and Eastern United States, EPRI Report NP-4726 (July 1986) and the Seismic Hazard Characterization of 69 Nuclear Plant Sites East of the Rocky Mountains, Lawrence Livermore National Laboratory Model, (Bernreuter et al., 1989). The objective of the CEUS SSC Project is to develop a new seismic source model for the CEUS using a Senior Seismic Hazard Analysis Committee (SSHAC) Level 3 assessment process. The goal of the SSHAC process is to represent the center, body, and range of technically defensible interpretations of the available data, models, and methods. Input to a probabilistic seismic hazard analysis (PSHA) consists of both seismic source characterization and ground motion characterization. These two components are used to calculate probabilistic hazard results (or seismic hazard curves) at a particular site. This report provides a new seismic source model. Results and Findings The product of this report is a regional CEUS SSC model. This model includes consideration of an updated database, full assessment and incorporation of uncertainties, and the range of diverse technical interpretations from the larger technical community. The SSC model will be widely applicable to the entire CEUS, so this project uses a ground motion model that includes generic variations to allow for a range of representative site conditions (deep soil, shallow soil, hard rock). Hazard and sensitivity calculations were conducted at seven test sites representative of different CEUS hazard environments. Challenges and Objectives The regional CEUS SSC model will be of value to readers who are involved in PSHA work, and who wish to use an updated SSC model. This model is based on a comprehensive and traceable process, in accordance with SSHAC guidelines in NUREG/CR-6372, Recommendations for Probabilistic

  15. Headspace analysis study of evaporation rate of perfume ingredients applied onto skin.

    Science.gov (United States)

    Vuilleumier, C; Flament, I; Sauvegrain, P

    1995-04-01

    Synopsis Diffusion of perfume ingredients from skin or hair is measured using an original method based on dynamic headspace technology. This has been used for pure odorants, fine fragrances, as well as for perfumed cosmetic applications such as soaps, creams or shampoos, in order to characterize diffusion processes and air/skin or air/hair partitioning. Accordingly, a special collection system, applied on the inner face of the forearm, has been developed, allowing the adsorption of diffusing organic vapours from skin onto Tenax (poly-diphenyl phenylene oxide) with a controlled air flow rate. A simple model composition containing eleven volatile synthetic odorants was prepared in an alcoholic matrix and the solution was applied onto the skin. The diffusion rate of the different components was measured by determining the concentration of each in the gas phase versus time. Conversely, the same experiment was effected by the application of an alcoholic solution of each individual component. In this manner, the relative diffusion from skin of the components alone or mixed was compared using the same experimental technique. The effect of a musky component was also tested. Both compositions (with and without musk) were then applied in a soap base. Thus, following a rigorous protocol, the forearm was washed with the perfumed soap and rinsed with water before collection of the headspace. The results show the different diffusion rates of the individual odorants. In particular, components evaporate slower from the skin when they have been applied from a soap bar compared to when they have been applied from alcoholic solution. We also present results describing the characterization of skin types using a panel comprised of 80 people (40 females and 40 males); amount of sebum, hydration and pH were systematically measured on different parts of the face, the neck as well as the outer and inner faces of the forearm. The panelists were then classified into different sub

  16. Anatomical characterization of subcortical descending projections to the inferior colliculus in mouse.

    Science.gov (United States)

    Patel, Mili B; Sons, Stacy; Yudintsev, Georgiy; Lesicko, Alexandria M H; Yang, Luye; Taha, Gehad A; Pierce, Scott M; Llano, Daniel A

    2017-03-01

    Descending projections from the thalamus and related structures to the midbrain are evolutionarily highly conserved. However, the basic organization of this auditory thalamotectal pathway has not yet been characterized. The purpose of this study was to obtain a better understanding of the anatomical and neurochemical features of this pathway. Analysis of the distributions of retrogradely labeled cells after focal injections of retrograde tracer into the inferior colliculus (IC) of the mouse revealed that most of the subcortical descending projections originated in the brachium of the IC and the paralaminar portions of the auditory thalamus. In addition, the vast majority of thalamotectal cells were found to be negative for the calcium-binding proteins calbindin, parvalbumin, or calretinin. Using two different strains of GAD-GFP mice, as well as immunostaining for GABA, we found that a subset of neurons in the brachium of the IC is GABAergic, suggesting that part of this descending pathway is inhibitory. Finally, dual retrograde injections into the IC and amygdala plus corpus striatum as well into the IC and auditory cortex did not reveal any double labeling. These data suggest that the thalamocollicular pathway comprises a unique population of thalamic neurons that do not contain typical calcium-binding proteins and do not project to other paralaminar thalamic forebrain targets, and that a previously undescribed descending GABAergic pathway emanates from the brachium of the IC. J. Comp. Neurol. 525:885-900, 2017. © 2016 Wiley Periodicals, Inc.

  17. ECHO Project: a series of tools for studying and characterizing seismic sequences evolution

    Science.gov (United States)

    Falcone, Giuseppe; De Santis, Angelo; Di Giovambattista, Rita; Cianchini, Gianfranco; Murru, Maura; Calderoni, Giovanna; Lucente, Pio Francesco; De Gori, Pasquale; Frepoli, Alberto; Signanini, Patrizio; Rainone, Mario; Vessia, Giovanna

    2016-04-01

    One of the most ubiquitous problems in seismology is to discriminate between seismic sequences (a series of small-to-moderate earthquakes that culminate with a mainshock) and swarms (diffuse seismicity w/o mainshock), that can be easily done only after a certain class of earthquakes have occurred. We propose to put these phenomena under the same framework provided by the geosystemics (De Santis, 2009, 2014), where the planet Earth and its processes are seen from a holistic point of view, and the New Geophysics (Crampin et al., 2013), where fluid-saturated microcracks in almost all crustal rocks are so closely-spaced they verge on failure and hence are highly-compliant critical systems (Signanini and De Santis, 2012). In this context, nonlinear concepts typical of Chaos and Information theories are fundamental to study and characterize the various features of the series of seismic events, and, eventually, to discriminate between seismic sequences and swarms. The two theories imply the use of non-linear techniques which are innovative in seismology. The project ECHO ("Entropy and CHaOs: tools for studying and characterizing seismic sequences evolution"), a recent INGV-funded project, would aim at applying the above approaches in a more integrated way mainly to establish a suite of effective tools to disclose and characterise the principal features of the series of earthquakes which are of interest. In our view this will represent the very first step before to face the more challenging (but longer-term) problem of discriminating between the two kinds of series of seismic events. This poster will describe these kinds of preliminary activities and relative results in the framework of the project.

  18. Los Alamos National Laboratory Yucca Mountain Site Characterization Project 1992 quality program status report

    Energy Technology Data Exchange (ETDEWEB)

    Bolivar, S.L.; Burningham, A.; Chavez, P. [and others

    1994-03-01

    This status report summarizes the activities and accomplishments of the Los Alamos Yucca Mountain Site Characterization Project`s quality assurance program for calendar year 1992. The report includes major sections on Program Activities and Trend Analysis. Program Activities are discussed periodically at quality meetings. The most significant issue addressed in 1992 has been the timely revision of quality administrative procedures. The procedure revision process was streamlined from 55 steps to 7. The number of forms in procedures was reduced by 38%, and the text reduced by 29%. This allowed revision in 1992 of almost half of all implementing procedures. The time necessary to complete the revision process (for a procedure) was reduced from 11 months to 3 months. Other accomplishments include the relaxation of unnecessarily strict training requirements, requiring quality assurance reviews only from affected organizations, and in general simplifying work processes. All members of the YMP received training to the new Orientation class Eleven other training classed were held. Investigators submitted 971 records to the Project and only 37 were rejected. The software program has 115 programs approved for quality-affecting work. The Project Office conducted 3 audits and 1 survey of Los Alamos activities. We conducted 14 audits and 4 surveys. Eight corrective action reports were closed, leaving only one open. Internally, 22 deficiencies were recognized. This is a decrease from 65 in 1991. Since each deficiency requires about 2 man weeks to resolve, the savings are significant. Problems with writing acceptable deficiency reports have essentially disappeared. Trend reports for 1992 were examined and are summarized herein. Three adverse trends have been closed; one remaining adverse trend will be closed when the affected procedures are revised. The number of deficiencies issued to Los Alamos compared to other participants is minimal.

  19. Imaging and characterizing exo-Earths at 10 microns - The TIKI project

    Science.gov (United States)

    Marchis, F.; Christian, M.; Bradley, C.; Blain, C.; Lardiere, O.; Melis, C.; Packham, C.; Skemer, A.

    2016-12-01

    The next major breakthrough in the exoplanet field will be the discovery and characterization of an Earth-like planet in the solar neighborhood. While there are many promising ways to achieve such a detection, imaging at a wavelength of 10-micron offers a unique, fast and cost-effective approach to detect and characterize planets around nearby stars with physical properties similar to Earth (same size, incident stellar radiation, low clouds and average black body temperature of 288K). Instead of detecting reflected light from such planets (typical of shorter wavelength ground/space missions), the 10-micron band is sensitive to the thermal emission of planets, being very close to the peak emission wavelength of 288K black bodies. In less than 200h worth of observing, a 10-micron imager could detect the thermal emission of an Earth-like planet around Alpha Centauri A and B on current 8-m telescopes. The same instrument on a 30-m telescope, like the TMT, will be quite competitive, allowing such discovery and characterization in an hour. We will present the design of such instrument for the 8m Gemini South telescope, as well as simulations of observations and the schedule of our project which aims at a first light in 2019.

  20. Dynamic headspace analysis of the release of volatile organic compounds from ethanolic systems by direct APCI-MS.

    Science.gov (United States)

    Tsachaki, Maroussa; Linforth, Robert S T; Taylor, Andrew J

    2005-10-19

    Static equilibrium headspace was diluted with a stream of nitrogen to study the stability of the volatile headspace concentration. The headspace dilution profile of 18 volatile compounds above aqueous and ethanolic solutions was measured in real time using atmospheric pressure chemical ionization-mass spectrometry. Under dynamic conditions the volatiles headspace concentration above water solutions decreased readily upon dilution. The presence of ethanol helped to maintain the volatile headspace concentration when the ethanol solution concentration was above 50 mL/L. This effect was such that under dynamic conditions the absolute volatile concentration above an ethanolic solution was higher than that above an aqueous solution, contrary to results observed in equilibrium studies. The ratio of the headspace concentration of volatiles above ethanolic 120 mL/L and water solutions was correlated to their air/water partition coefficient.

  1. Vadose zone characterization project at the Hanford Tank Farms: U Tank Farm Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    The U.S. Department of Energy Grand Junction Office (DOE-GJO) was tasked by the DOE Richland Operations Office (DOE-RL) to perform a baseline characterization of the gamma-ray-emitting radionuclides that are distributed in the vadose zone sediments beneath and around the single-shell tanks (SSTs) at the Hanford Site. The intent of this characterization is to determine the nature and extent of the contamination, to identify contamination sources when possible, and to develop a baseline of the contamination distribution that will permit future data comparisons. This characterization work also allows an initial assessment of the impacts of the vadose zone contamination as required by the Resource Conservation and Recovery Act (RCRA). This characterization project involves acquiring information regarding vadose zone contamination with borehole geophysical logging methods and documenting that information in a series of reports. This information is presently limited to detection of gamma-emitting radionuclides from both natural and man-made sources. Data from boreholes surrounding each tank are compiled into individual Tank Summary Data Reports. The data from each tank in a tank farm are then compiled and summarized in a Tank Farm Report. This document is the Tank Farm Report for the U Tank Farm. Logging operations used high-purity germanium detection systems to acquire laboratory-quality assays of the gamma-emitting radionuclides in the sediments around and below the tanks. These assays were acquired in 59 boreholes that surround the U Tank Farm tanks. Logging of all boreholes was completed in December 1995, and the last Tank Summary Data Report for the U Tank Farm was issued in September 1996.

  2. THE BC CRIBS & TRENCHES GEOPHYSICAL CHARACTERIZATION PROJECT ONE STEP FORWARD IN HANFORDS CLEANUP PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    BENECKE, MN.W.

    2006-02-22

    A geophysical characterization project was conducted at the BC Cribs and Trenches Area, located south of 200 East at the Hanford Site. The area consists of 26 waste disposal trenches and cribs, which received approximately 30 million gallons of liquid waste from the uranium recovery process and the ferrocyanide processes associated with wastes generated by reprocessing nuclear fuel. Waste discharges to BC Cribs contributed perhaps the largest liquid fraction of contaminants to the ground in the 200 Areas. The site also includes possibly the largest inventory of Tc-99 ever disposed to the soil at Hanford with an estimated quantity of 400 Ci. Other waste constituents included high volumes of nitrate and U-238. The geophysical characterization at the 50 acre site primarily included high resolution resistivity (HRR). The resistivity technique is a non-invasive method by which electrical resistivity data are collected along linear transects, and data are presented as continuous profiles of subsurface electrical properties. The transects ranged in size from about 400-700 meters and provided information down to depths of 60 meters. The site was characterized by a network of 51 HRR lines with a total of approximately 19.7 line kilometers of data collected parallel and perpendicular to the trenches and cribs. The data were compiled to form a three-dimensional representation of low resistivity values. Low resistivity, or high conductivity, is indicative of high ionic strength soil and porewater resulting from the migration of nitrate and other inorganic constituents through the vadose zone. High spatial density soil data from a single borehole, that included coincident nitrate concentrations, electrical conductivity, and Tc-99, were used to transform the electrical resistivity data into a nitrate plume. The plume was shown to extend laterally beyond the original boundaries of the waste site and, in one area, to depths that exceeded the characterization strategy. It is

  3. Characterization and classification of pequi trees (Caryocar brasiliense Camb. based on the profile of volatile constituents using headspace solid-phase microextraction - gas chromatography - mass spectrometry and multivariate analysis Caracterização e classificação de pequizeiros (Caryocar brasiliense Camb. baseadas no perfil de constituintes voláteis usando microextração em fase sólida no modo headspace - cromatografia a gás - espectrometria de massas e análise multivariada

    Directory of Open Access Journals (Sweden)

    Renata França Cassimiro Belo

    2013-02-01

    Full Text Available In order to determine the variability of pequi tree (Caryocar brasiliense Camb. populations, volatile compounds from fruits of eighteen trees representing five populations were extracted by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. Seventy-seven compounds were identified, including esters, hydrocarbons, terpenoids, ketones, lactones, and alcohols. Several compounds had not been previously reported in the pequi fruit. The amount of total volatile compounds and the individual compound contents varied between plants. The volatile profile enabled the differentiation of all of the eighteen plants, indicating that there is a characteristic profile in terms of their origin. The use of Principal Component Analysis and Cluster Analysis enabled the establishment of markers (dendrolasin, ethyl octanoate, ethyl 2-octenoate and β-cis-ocimene that discriminated among the pequi trees. According to the Cluster Analysis, the plants were classified into three main clusters, and four other plants showed a tendency to isolation. The results from multivariate analysis did not always group plants from the same population together, indicating that there is greater variability within the populations than between pequi tree populations.A fim de determinar a variabilidade de populações de pequizeiro (Caryocar brasiliense Camb., compostos voláteis de frutos de dezoito árvores representando cinco populações foram extraídos por microextração em fase sólida no modo headspace e analisados por cromatografia a gás acoplada à espectrometria de massas. Setenta e sete compostos foram identificados, incluindo ésteres, hidrocarbonetos, terpenoides, cetonas, lactonas e álcoois. Vários compostos não haviam sido encontrados anteriormente no fruto. A quantidade total e a composição de voláteis variaram entre as plantas. O perfil volátil permitiu a diferenciação de todas as dezoito plantas, indicando que há um

  4. Characterization of new FPS (Focus Projection and Scale) vidicons for scientific imaging applications

    Science.gov (United States)

    Yates, G. J.; Jaramillo, S. A.; Holmes, V. H.; Black, J. P.

    1988-06-01

    Several new photoconductors now commercially available as targets in Type 7803 FPS (Focus Projection and Scan) electrostatically focussed vidicons have been characterized for use as radiometric sensors in transient illumination and single frame applications. These include Saticon (Se + Te + As), Newvicon (ZnSe), Pasecon (CdSe), and Plumbicon (PbO). Samples from several domestic and foreign manufacturers have been evaluated for photoconductive response time and responsivity at selected narrow wavelength bands, including 410 nm, 560 nm, and 822 nm. These data are compared with performance data from older target materials including antimony trisulfide (Sb2S3) and silicon. Dynamic range and resolution trade-offs as functions of read-beam aperture diameter and raster size are also presented. The point spread functions for standard 1-mil vidicons and for increased apertures of 1.5, 2.0, 3.0, and 4.0-mil are also discussed.

  5. Fuel Thermo-physical Characterization Project: Evaluation of Models to Calculate Thermal Diffusivity of Layered Composites

    Energy Technology Data Exchange (ETDEWEB)

    Burkes, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Amanda J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gardner, Levi D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Andrew M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Huber, Tanja K. [Technische Universität München, Munich (Germany); Breitkreutz, Harald [Technische Universität München, Munich (Germany)

    2015-02-11

    The Office of Material Management and Minimization Fuel Thermo-physical Characterization Project at Pacific Northwest National Laboratory (PNNL) is tasked with using PNNL facilities and processes to receive irradiated low enriched uranium-molybdenum fuel plate samples and perform analyses in support of the Office of Material Management and Minimization Reactor Conversion Program. This work is in support of the Fuel Development Pillar that is managed by Idaho National Laboratory. A key portion of the scope associated with this project was to measure the thermal properties of fuel segments harvested from plates that were irradiated in the Advanced Test Reactor. Thermal diffusivity of samples prepared from the fuel segments was measured using laser flash analysis. Two models, one developed by PNNL and the other developed by the Technische Universität München (TUM), were evaluated to extract the thermal diffusivity of the uranium-molybdenum alloy from measurements made on the irradiated, layered composites. The experimental data of the “TC” irradiated fuel segment was evaluated using both models considering a three-layer and five-layer system. Both models are in acceptable agreement with one another and indicate that the zirconium diffusion barrier has a minimal impact on the overall thermal diffusivity of the monolithic U-Mo fuel.

  6. Retinal projections and neurochemical characterization of the pregeniculate nucleus of the common marmoset (Callithrix jacchus).

    Science.gov (United States)

    Lima, Ruthnaldo R M; Pinato, Luciana; Nascimento, Rayane B S; Engelberth, Rovena Clara G J; Nascimento, Expedito S Junior; Cavalcante, Judney C; Britto, Luiz R G; Costa, Miriam S M O; Cavalcante, Jeferson S

    2012-05-01

    In mammals, the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) are the main components of the circadian timing system. The SCN is the site of the endogenous biological clock that generates rhythms and synchronizes them to environmental cues. The IGL is a key structure that modulates SCN activity and is responsible for the transmission of non-photic information to the SCN, thus participating in the integration between photic and non-photic stimuli. Both the SCN and IGL receive projections of retinal ganglion cells and the IGL is connected to the SCN through the geniculohypothalamic tract. Little is known about these structures in the primate brain and the pregeniculate nucleus (PGN) has been suggested to be the primate equivalent of the rodent IGL. The aim of this study was to characterize the PGN of a primate, the common marmoset (Callithrix jacchus), and to analyze its retinal afferents. Here, the marmoset PGN was found to be organized into three subsectors based on neuronal size, pattern of retinal projections, and the distribution of neuropeptide Y-, GAD-, serotonin-, enkephalin- and substance P-labeled terminals. This pattern indicates that the marmoset PGN is equivalent to the IGL. This detailed description contributes to the understanding of the circadian timing system in this primate species considering the importance of the IGL within the context of circadian regulation.

  7. Advanced reservoir characterization for improved oil recovery in a New Mexico Delaware basin project

    Energy Technology Data Exchange (ETDEWEB)

    Martin, F.D.; Kendall, R.P.; Whitney, E.M. [Dave Martin and Associates, Inc., Socorro, NM (United States)] [and others

    1997-08-01

    The Nash Draw Brushy Canyon Pool in Eddy County, New Mexico is a field demonstration site in the Department of Energy Class III program. The basic problem at the Nash Draw Pool is the low recovery typically observed in similar Delaware fields. By comparing a control area using standard infill drilling techniques to a pilot area developed using advanced reservoir characterization methods, the goal of the project is to demonstrate that advanced technology can significantly improve oil recovery. During the first year of the project, four new producing wells were drilled, serving as data acquisition wells. Vertical seismic profiles and a 3-D seismic survey were acquired to assist in interwell correlations and facies prediction. Limited surface access at the Nash Draw Pool, caused by proximity of underground potash mining and surface playa lakes, limits development with conventional drilling. Combinations of vertical and horizontal wells combined with selective completions are being evaluated to optimize production performance. Based on the production response of similar Delaware fields, pressure maintenance is a likely requirement at the Nash Draw Pool. A detailed reservoir model of pilot area was developed, and enhanced recovery options, including waterflooding, lean gas, and carbon dioxide injection, are being evaluated.

  8. Advanced Compatibility Characterization Of AF-M315E With Spacecraft Propulsion System Materials Project

    Science.gov (United States)

    McClure, Mark B.; Greene, Benjamin

    2014-01-01

    All spacecraft require propulsion systems for thrust and maneuvering. Propulsion systems can be chemical, nuclear, electrical, cold gas or combinations thereof. Chemical propulsion has proven to be the most reliable technology since the deployment of launch vehicles. Performance, storability, and handling are three important aspects of liquid chemical propulsion. Bipropellant systems require a fuel and an oxidizer for propulsion, but monopropellants only require a fuel and a catalyst for propulsion and are therefore simpler and lighter. Hydrazine is the state of the art propellant for monopropellant systems, but has drawbacks because it is highly hazardous to human health, which requires extensive care in handling, complex ground ops due to safety and environmental considerations, and lengthy turnaround times for reusable spacecraft. All users of hydrazine monopropellant must contend with these issues and their associated costs. The development of a new monopropellant, intended to replace hydrazine, has been in progress for years. This project will apply advanced techniques to characterize the engineering properties of materials used in AF-M315E propulsion systems after propellant exposure. AF-M315E monopropellant has been selected HQ's Green Propellant Infusion Mission (GPIM) to replace toxic hydrazine for improved performance and reduce safety and health issues that will shorten reusable spacecraft turn-around time. In addition, this project will fundamentally strengthen JSC's core competency to evaluate, use and infuse liquid propellant systems.

  9. The DLR project Wirbelschleppe. Detecting, characterizing, controlling, attenuating, understanding, and predicting aircraft wake vortices

    Energy Technology Data Exchange (ETDEWEB)

    Holzaepfel, F. (ed.)

    2008-07-01

    This collection of reports presents an excerpt of the investigations that were performed in the framework of the DLR Projekt Wirbelschleppe. A similar sample of reports was presented as part of three dedicated wake vortex sessions accomplished at the 1{sup st} European Air and Space Conference (CEAS 2007) and Deutscher Luft- und Raumfahrtkongress 2007 in Berlin. The Projekt Wirbelschleppe was conducted in two phases in the time frame from 1999 to 2007 with the five contributing DLR Institutes: Institute of Atmospheric Physics, Institute of Aerodynamics and Flow Technology, Institute of Flight Systems, Institute of Flight Guidance, Institute of Robotics and Mechatronics and the Institute of Aeronautics and Astronautics of the University of Technology Berlin. The project unified a multitude of different aspects and disciplines of wake vortex research which can be characterized by four main themes: - minimization of wake vortices by measures at the aircraft; - development and demonstration of a system for wake vortex prediction and observation; - airborne wake vortex detection and active control; - integration of systems into air traffic control. The Projekt Wirbelschleppe greatly benefited from the European projects AWIATOR, ATC-Wake, Credos, C-Wake, Eurowake, FAR-Wake, FLYSAFE, I-Wake, S-Wake, WakeNet, WakeNet2-Europe, WakeNet3-Europe, and Wavenc. DLR's wake vortex activities will be continued in the Projekt Wetter and Fliegen (2008-2011): Because the current compilation represents only a limited extract of the accomplished work, it is completed by a list of references emerging from the project. (orig.)

  10. Fiscal year 1997 Memorandum of Understanding for the TWRS characterization project

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, R.D., Fluor Daniel Hanford

    1997-02-27

    During fiscal year 1997, the level of success achieved by the Tank Waste Remediation System (TWRS) shall be determined by specific performance measures. These measures take the form of significant deliverables, one of which is the completion of Tank Characterization Reports (TCRs). In order to achieve success regarding the TCR performance deliverable, multiple organizations across TWRS must work together. Therefore, the requirements and expectations needed from each of these TWRS organizations were examined in order to gain an understanding of the performance necessary from each organization to achieve the end deliverable. This memorandum of understanding (MOU) documents the results of this review and establishes the performance criteria by which TWRS will assess its progress and success. These criteria have been determined based upon a TWRS Characterization Project budget of $56.8 million for fiscal year 1997; if this budget is changed or the currently identified workscope is modified, this MOU will need to be revised accordingly. This MOU is subdivided into six sections, where sections three through six each identify individual interfaces between TWRS organizations. The specific performance criteria related to each TWRS organizational interface are then delineated in the section, along with any additional goals or issues pertaining to that interface.

  11. Fiscal Year 1999 memorandum of understanding for the TWRS characterization project

    Energy Technology Data Exchange (ETDEWEB)

    HUNT, J.W.

    1998-11-11

    During fiscal year 1999, the level of success achieved by the Tank Waste Remediation System (TWRS) shall be determined by specific performance measures. These measures take the form of significant deliverables, one of which is the completion of Tank Characterization Reports (TCRS). In order to achieve success regarding the TCR performance deliverable, multiple organizations across TWRS must work together. Therefore, the requirements and expectations needed from each of these TWRS organizations were examined in order to gain an understanding of the performance necessary from each organization to achieve the end deliverable. This memorandum of understanding (MOU) documents the results of this review and establishes the performance criteria by which TWRS will assess its progress and success. These criteria have been determined based upon a TWRS Characterization Project budget of $42.1 million for fiscal year 1999; if this budget is changed or the currently identified workscope is modified, this MOU will need to be revised accordingly. This MOU is subdivided into six sections, where sections three through six each identify individual interfaces between TWRS organizations. The specific performance criteria related to each TWRS organizational interface are then delineated in the section, along with any additional goals or issues pertaining to that interface.

  12. Fiscal year 1998 memorandum of understanding for the TWRS characterization project

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, R.D.

    1998-03-24

    During fiscal year 1998, the level of success achieved by the Tank Waste Remediation System (TWRS) shall be determined by specific performance measures. These measures take the form of significant deliverables, one of which is the completion of Tank Characterization Reports (TCRs). In order to achieve success regarding the TCR performance deliverable, multiple organizations across TWRS must work together. Therefore, the requirements and expectations needed from each of these TWRS organizations were examined in order to gain an understanding of the performance necessary from each organization to achieve the end deliverable. This memorandum of understanding (MOU) documents the results of this review and establishes the performance criteria by which TWRS will assess its progress and success. These criteria have been determined based upon a TWRS Characterization Project budget of $47.5 million for fiscal year 1998; if this budget is changed or the currently identified work scope is modified, this MOU will need to be revised accordingly. This MOU is subdivided into six sections, where sections three through six each identify individual interfaces between TWRS organizations. The specific performance criteria related to each TWRS organizational interface are then delineated in the section, along with any additional goals or issues pertaining to that interface.

  13. YUCCA MOUNTAIN SITE CHARACTERIZATIONS PROJECT TUNNEL BORING MACHINE (TBM) SYSTEM SAFETY ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    1997-02-19

    The purpose of this analysis is to systematically identify and evaluate hazards related to the tunnel boring machine (TBM) used in the Exploratory Studies Facility (ESF) at the Yucca Mountain Site Characterization Project. This process is an integral part of the systems engineering process; whereby safety is considered during planning, design, testing, and construction. Since the TBM is an ''as built'' system, the M&O is conducting the System Safety Analysis during the construction or assembly phase of the TBM. A largely qualitative approach was used since a radiological System Safety Analysis is not required. The risk assessment in this analysis characterizes the accident scenarios associated with the TBM in terms of relative risk and includes recommendations for mitigating all identified risks. The priority for recommending and implementing mitigation control features is: (1) Incorporate measures to reduce risks and hazards into the system/subsystem/component design, (2) add safety features and capabilities to existing designs, and (3) develop procedures and conduct training to increase worker awareness of potential hazards, on methods to reduce exposure to hazards, and on the actions required to avoid accidents or correct hazardous conditions. The scope of this analysis is limited to the TBM during normal operations, excluding hazards occurring during assembly and test of the TBM or maintenance of the TBM equipment.

  14. Cost estimate of high-level radioactive waste containers for the Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Russell, E.W.; Clarke, W. [Lawrence Livermore National Lab., CA (United States); Domian, H.A. [Babcock and Wilcox Co., Lynchburg, VA (United States); Madson, A.A. [Kaiser Engineers California Corp., Oakland, CA (United States)

    1991-08-01

    This report summarizes the bottoms-up cost estimates for fabrication of high-level radioactive waste disposal containers based on the Site Characterization Plan Conceptual Design (SCP-CD). These estimates were acquired by Babcock and Wilcox (B&S) under sub-contract to Lawrence Livermore National Laboratory (LLNL) for the Yucca Mountain Site Characterization Project (YMP). The estimates were obtained for two leading container candidate materials (Alloy 825 and CDA 715), and from other three vendors who were selected from a list of twenty solicited. Three types of container designs were analyzed that represent containers for spent fuel, and for vitrified high-level waste (HLW). The container internal structures were assumed to be AISI-304 stainless steel in all cases, with an annual production rate of 750 containers. Subjective techniques were used for estimating QA/QC costs based on vendor experience and the specifications derived for the LLNL-YMP Quality Assurance program. In addition, an independent QA/QC analysis is reported which was prepared by Kasier Engineering. Based on the cost estimates developed, LLNL recommends that values of $825K and $62K be used for the 1991 TSLCC for the spent fuel and HLW containers, respectively. These numbers represent the most conservative among the three vendors, and are for the high-nickel anstenitic steel (Alloy 825). 6 refs., 7 figs.

  15. Environmental assessment for the Groundwater Characterization Project, Nevada Test Site, Nye County, Nevada; Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-08-01

    The US Department of Energy (DOE) proposes to conduct a program to characterize groundwater at the Nevada Test Site (NTS), Nye County, Nevada, in accordance with a 1987 DOE memorandum stating that all past, present, and future nuclear test sites would be treated as Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites (Memorandum from Bruce Green, Weapons Design and Testing Division, June 6, 1987). DOE has prepared an environmental assessment (DOE/EA-0532) to evaluate the environmental consequences associated with the proposed action, referred to as the Groundwater Characterization Project (GCP). This proposed action includes constructing access roads and drill pads, drilling and testing wells, and monitoring these wells for the purpose of characterizing groundwater at the NTS. Long-term monitoring and possible use of these wells in support of CERCLA, as amended by the Superfund Amendments and Reauthorization Act, is also proposed. The GCP includes measures to mitigate potential impacts on sensitive biological, cultural and historical resources, and to protect workers and the environment from exposure to any radioactive or mixed waste materials that may be encountered. DOE considers those mitigation measures related to sensitive biological, cultural and historic resources as essential to render the impacts of the proposed action not significant, and DOE has prepared a Mitigation Action Plan (MAP) that explains how such mitigations will be planned and implemented. Based on the analyses presented in the EA, DOE has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act of 1969 (NEPA). Therefore, preparation of an environmental impact statement is not required and the Department is issuing this FONSI.

  16. Tank 241-C-109 vapor sampling and analysis tank characterization report. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L.

    1995-05-31

    This report presents the details of the Hanford waste tank characterization study for tank C-109. The drivers and objectives of the waste tank headspace vapor sampling and analysis were in accordance with procedures that were presented in other reports.

  17. Seasonal changes in the composition of passively ventilated waste tank headspaces

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L.; Hayes, J.C.; Buckley, L.L.; Jensen, L.; Pennington, L.D.; Wilmarth, S.R.

    1997-08-01

    The headspaces of four passively ventilated high-level radioactive waste tanks were sampled five times over a one-year period to evaluate seasonal changes in composition. Tanks BX-104, BY-108, C-107, and SX-102 were selected for the study on the bases of their widely varying headspace compositions, waste types, and physical headspace conditions. Samples were collected and analyzed for inorganic vapors, permanent gases, and organic vapors. Data from the 20 sampling events were compiled and reviewed. Raw mass spectral data for organic vapors were reprocessed by a single analyst. Measurement precision for results within individual sampling events, which includes both sampling and analytical random errors, was generally within the requirement of a 25% relative standard deviation. Data were fit to an analysis of variance (ANOVA) model and tested for correlation with headspace temperature. The ANOVA results indicate that the majority of headspace constituents studied were at relatively constant levels during the year-long study. The percent relative standard deviation (RSD{sub TIME}) of analyte means obtained for the five sampling events were generally low; only 15 of the 152 analytes had RSD{sub TIME} values above 60%. These highest RSD{sub TIME} values were obtained for 13 organic vapors in Tank BX-104 and two permanent gases in Tank C-107.

  18. Influence of headspace pressure on methane production in Biochemical Methane Potential (BMP) tests.

    Science.gov (United States)

    Valero, David; Montes, Jesús A; Rico, José Luis; Rico, Carlos

    2016-02-01

    The biochemical methane potential test is the most commonly applied method to determine methane production from organic wastes. One of the parameters measured is the volume of biogas produced which can be determined manometrically by keeping the volume constant and measuring increases in pressure. In the present study, the effect of pressure accumulation in the headspace of the reactors has been studied. Triplicate batch trials employing cocoa shell, waste coffee grounds and dairy manure as substrates have been performed under two headspace pressure conditions. The results obtained in the study showed that headspace overpressures higher than 600mbar affected methane production for waste coffee grounds. On the contrary, headspace overpressures within a range of 600-1000mbar did not affect methane production for cocoa shell and dairy manure. With the analyses performed in the present work it has not been possible to determine the reasons for the lower methane yield value obtained for the waste coffee grounds under high headspace pressures. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Evaluation of headspace equilibration methods for quantifying greenhouse gases in groundwater.

    Science.gov (United States)

    Jahangir, M M R; Johnston, P; Khalil, M I; Grant, J; Somers, C; Richards, K G

    2012-11-30

    The objective of the study was to evaluate the different headspace equilibration methods for the quantification of dissolved greenhouse gases in groundwater. Groundwater samples were collected from wells with contrasting hydrogeochemical properties and degassed using the headspace equilibration method. One hundred samples from each well were randomly selected, treatments were applied and headspace gases analysed by gas chromatography. Headspace equilibration treatments varied helium (He):water ratio, shaking time and standing time. Mean groundwater N(2)O, CO(2) and CH(4) concentrations were 0.024 mg N L(-1), 13.71 mg C L(-1) and 1.63 μg C L(-1), respectively. All treatments were found to significantly influence dissolved gas concentrations. Considerable differences in the optimal He:water ratio and standing time were observed between the three gases. For N(2)O, CO(2) and CH(4) the optimum operating points for He:water ratio was 4.4:1, 3:1 and 3.4:1; shaking time was 13, 12 and 13 min; and standing time was 63, 17 and 108 min, respectively. The headspace equilibration method needs to be harmonised to ensure comparability between studies. The experiment reveals that He:water ratio 3:1 and shaking time 13 min give better estimation of dissolved gases than any lower or higher ratios and shaking times. The standing time 63, 17 and 108 min should be applied for N(2)O, CO(2) and CH(4), respectively.

  20. Dynamic headspace generation and quantitation of triacetone triperoxide vapor.

    Science.gov (United States)

    Giordano, Braden C; Lubrano, Adam L; Field, Christopher R; Collins, Greg E

    2014-02-28

    Two methods for quantitation of triacetone triperoxide (TATP) vapor using a programmable temperature vaporization (PTV) inlet coupled to a gas chromatography/mass spectrometer (GC/MS) have been demonstrated. The dynamic headspace of bulk TATP was mixed with clean humid air to produce a TATP vapor stream. Sampling via a heated transfer line to a PTV inlet with a Tenax-TA™ filled liner allowed for direct injection of the vapor stream to a GC/MS for vapor quantitation. TATP was extracted from the vapor stream and subsequently desorbed from the PTV liner for splitless injection on the GC column. Calibration curves were prepared using solution standards with a standard split/splitless GC inlet for quantitation of the TATP vapor. Alternatively, vapor was sampled onto a Tenax-TA™ sample tube and placed into a thermal desorption system. In this instance, vapor was desorbed from the tube and subsequently trapped on a liquid nitrogen cooled PTV inlet. Calibration curves for this method were prepared from direct liquid injection of standards onto samples tube with the caveat that a vacuum is applied to the tube during deposition to ensure that the volatile TATP penetrates into the tube. Vapor concentration measurements, as determined by either GC/MS analysis or mass gravimetry of the bulk TATP, were statistically indistinguishable. Different approaches to broaden the TATP vapor dynamic range, including diluent air flow, sample chamber temperature, sample vial orifice size, and sample size are discussed. Vapor concentrations between 50 and 5400ngL(-1) are reported, with stable vapor generation observed for as long as 60 consecutive hours.

  1. Characterization of ionic currents of cells of the subfornical organ that project to the supraoptic nuclei

    Science.gov (United States)

    Johnson, R. F.; Beltz, T. G.; Jurzak, M.; Wachtel, R. E.; Johnson, A. K.

    1999-01-01

    The subfornical organ (SFO) is a forebrain structure that converts peripheral blood-borne signals reflecting the hydrational state of the body to neural signals and then through efferent fibers conveys this information to several central nervous system structures. One of the forebrain areas receiving input from the SFO is the supraoptic nucleus (SON), a source of vasopressin synthesis and control of release from the posterior pituitary. Little is known of the transduction and transmission processes by which this conversion of systemic information to brain input occurs. As a step in elucidating these mechanisms, the present study characterized the ionic currents of dissociated cells of the SFO that were identified as neurons that send efferents to the SON. A retrograde tracer was injected into the SON area in eleven-day-old rats. After three days for retrograde transport of the label, the SFOs of these animals were dissociated and plated for tissue culture. The retrograde tracer was used to identify the soma of SFO cells projecting to the SON so that voltage-dependent ionic currents using whole-cell voltage clamp methods could be studied. The three types of currents in labeled SFO neurons were characterized as a 1) rapid, transient inward current that can be blocked by tetrodotoxin (TTX) characteristic of a sodium current; 2) slow-onset sustained outward current that can be blocked by tetraethylammonium (TEA) characteristic of a delayed rectifier potassium current; and 3) remaining outward current that has a rapid-onset and transient characteristic of a potassium A-type current. Copyright 1999 Elsevier Science B.V.

  2. Status of volcanism studies for the Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Crowe, B.; Perry, F.; Murrell, M.; Poths, J.; Valentine, G.A. [Los Alamos National Lab., NM (United States); Wells, S. [Univ. of California, Riverside, CA (United States); Bowker, L.; Finnegan, K. [Univ. of Nevada, Las Vegas, NV (United States); Geissman, J.; McFadden, L.

    1995-02-01

    Chapter 1 introduces the volcanism issue for the Yucca Mountain site and provides the reader with an overview of the organization, content, and significant conclusions of this report. The risk of future basaltic volcanism is the primary topic of concern including both events that intersect a potential repository and events that occur near or within the waste isolation system of a repository. Chapter 2 describes the volcanic history of the Yucca Mountain region (YMR) and emphasizes the Pliocene and Quaternary volcanic record, the interval of primary concern for volcanic risk assessment. The Lathrop Wells volcanic center is described in detail because it is the youngest basalt center in the YMR. Chapter 3 describes the tectonic setting of the YMR and presents and assesses the significance of multiple alternative tectonic models. Geophysical data are described for the YMR and are used as an aid to understand the distribution of basaltic volcanic centers. Chapter 4 discusses the petrologic and geochemical features of basaltic volcanism in the YMR, the southern Great Basin and the Basin and Range province. The long time of activity and characteristic small volume of the Postcaldera basalt of the YMR result in one of the lowest eruptive rates in a volcanic field in the southwest United States. Chapter 5 summarizes current concepts of the segregation, ascent, and eruption of basalt magma. Chapter 6 summarizes the history of volcanism studies (1979 through early 1994), including work for the Yucca Mountain Site Characterization Project and overview studies by the state of Nevada and the Nuclear Regulatory Commission. Chapter 7 summarizes probabilistic volcanic hazard assessment using a three-part conditional probability model. Chapter 8 describes remaining volcanism work judged to be needed to complete characterization studies for the YMR. Chapter 9 summarizes the conclusions of this volcanism status report.

  3. Development of the headspace Family and Friends Satisfaction Scale: Findings from a pilot study.

    Science.gov (United States)

    Nicholas, Angela; Holloway, Erin; Telford, Nic; Rickwood, Debra

    2017-04-19

    The primary aim of this pilot study was to determine the psychometric properties of the 18-item headspace Family and Friends Satisfaction Scale (hFAFSS). During August 2015, staff from 22 headspace centres approached family members and friends of young people attending headspace to complete the hFAFSS. Principal components analysis with oblique Promin rotation and polychoric correlations were used to assess the factor structure of the hFAFSS. There were 277 usable responses. Satisfaction was high, resulting in little variance. Parallel analyses suggested that the scale items tapped a single factor (68% of variance). This study is one of the first attempts to measure the satisfaction of family and friends with primary care-based youth mental health services. Satisfaction of family members and friends was shown to be high, but limited variance restricts the usability of the hFAFSS as an evaluation measure, and revision and further testing is needed. © 2017 John Wiley & Sons Australia, Ltd.

  4. Development of a sensory test method for odor measurement in a package headspace

    DEFF Research Database (Denmark)

    Reinbach, Helene Christine; Allesen-Holm, Bodil Helene; Kristoffersson, Lars

    2011-01-01

    The aim of the present study was to develop a sensory method to evaluate off-odors in a package headspace relative to a reference scale. Selection of panelists was performed with a questionnaire and with the Sniffin' stick test. A 1-butanol reference scale and three types of scales (a 15-cm line...... of the sensory panel to evaluation of different scaling techniques. Finally, a reliable and overtime fairly reproducible method for the evaluation of off-odors in the headspace of packages is presented....... to a physical intensity scale of 1-butanol and thus provides a valuable reference for comparing different package assessments over time. PRACTICAL APPLICATIONS A method for assessing off-odors in a package headspace is developed. The method development includes everything from selection and monitoring...

  5. Statistical analysis of hydrologic data for Yucca Mountain; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Rutherford, B.M.; Hall, I.J.; Peters, R.R.; Easterling, R.G.; Klavetter, E.A.

    1992-02-01

    The geologic formations in the unsaturated zone at Yucca Mountain are currently being studied as the host rock for a potential radioactive waste repository. Data from several drill holes have been collected to provide the preliminary information needed for planning site characterization for the Yucca Mountain Project. Hydrologic properties have been measured on the core samples and the variables analyzed here are thought to be important in the determination of groundwater travel times. This report presents a statistical analysis of four hydrologic variables: saturated-matrix hydraulic conductivity, maximum moisture content, suction head, and calculated groundwater travel time. It is important to modelers to have as much information about the distribution of values of these variables as can be obtained from the data. The approach taken in this investigation is to (1) identify regions at the Yucca Mountain site that, according to the data, are distinctly different; (2) estimate the means and variances within these regions; (3) examine the relationships among the variables; and (4) investigate alternative statistical methods that might be applicable when more data become available. The five different functional stratigraphic units at three different locations are compared and grouped into relatively homogeneous regions. Within these regions, the expected values and variances associated with core samples of different sizes are estimated. The results provide a rough estimate of the distribution of hydrologic variables for small core sections within each region.

  6. Intial characterization fo a commerical electron gun for profiling high intensity proton beams in Project X

    Energy Technology Data Exchange (ETDEWEB)

    Thurman-Keup, R.; Johnson, A.S.; Lumpkin, A.H.; Thangaraj, J.C.T.; Zhang, D.; /Fermilab; Blokland, W.; /Oak Ridge

    2011-03-01

    Measuring the profile of a high-intensity proton beam is problematic in that traditional invasive techniques such as flying wires don't survive the encounter with the beam. One alternative is the use of an electron beam as a probe of the charge distribution in the proton beam as was done at the Spallation Neutron Source at ORNL. Here we present an initial characterization of the beam from a commercial electron gun from Kimball Physics, intended for use in the Fermilab Main Injector for Project X. Despite the fact that the horizontal spot size is abnormally large in the high current measurement, the spot size at the downstream cross X2 is reasonable in the context of measuring the deflection. A thin foil OTR would help with the beam heating and should be tried. The next phase of this experiment is to simulate the proton beam with a pair of current carrying wires and to design and construct a fast deflector. Some of the remaining issues to be considered include determining the minimum beam current needed to observe the deflected beam for a given sweep time and the impact of longitudinal variations in the charge density of the bunch.

  7. Mechanical characterization of hyperelastic materials with fringe projection and optimization techniques

    Science.gov (United States)

    Genovese, Katia; Lamberti, Luciano; Pappalettere, Carmine

    2006-05-01

    This paper presents a new hybrid technique for mechanical characterization of hyperelastic materials. The research is motivated by the fact that standard identification procedures based on the fitting of strain-stress curves determined experimentally from planar biaxial tests may be inaccurate for non-uniform states of deformation. Therefore, we propose an alternative approach where the difference Ω between the displacement field measured with Projection Moiré and its counterpart predicted by FEM is minimized using non-linear optimization algorithms that finally find unknown material properties. In order to check the feasibility of the new procedure, we considered a thin latex membrane modelling it as a two-parameter Mooney-Rivlin (MR) hyperelastic material. The Ω function is minimized either using optimization routines available in a commercial finite element package and by implementing a global optimizer able to deal with non-linearity and non-convexity included in the identification process. In order to check accuracy of optimization results, target values of MR constants for the latex specimen tested have previously been determined by fitting experimental stress-strain data gathered from a standard planar biaxial tension test. Results indicate that the present hybrid identification procedure can determine accurately properties of the hyperelastic material under investigation. In fact, the average residual error on displacements was less than 1% while the difference between the MR constants found with optimization and their target values was less than 3.5%.

  8. Characterization of materials for a reactive transport model validation experiment: Interim report on the caisson experiment. Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Siegel, M.D.; Cheng, W.C. [Sandia National Labs., Albuquerque, NM (United States); Ward, D.B.; Bryan, C.R. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Earth and Planetary Sciences

    1995-08-01

    Models used in performance assessment and site characterization activities related to nuclear waste disposal rely on simplified representations of solute/rock interactions, hydrologic flow field and the material properties of the rock layers surrounding the repository. A crucial element in the design of these models is the validity of these simplifying assumptions. An intermediate-scale experiment is being carried out at the Experimental Engineered Test Facility at Los Alamos Laboratory by the Los Alamos and Sandia National Laboratories to develop a strategy to validate key geochemical and hydrological assumptions in performance assessment models used by the Yucca Mountain Site Characterization Project.

  9. Evidence That Certain Waste Tank Headspace Vapor Samples Were Contaminated by Semivolatile Polymer Additives

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, James L.

    2006-02-09

    Vapor samples collected from the headspaces of the Hanford Site high-level radioactive waste tanks in 1994 and 1995 using the Vapor Sampling System (VSS) were reported to contain trace levels of phthalates, antioxidants, and certain other industrial chemicals that did not have a logical origin in the waste. This report examines the evidence these chemicals were sampling artifacts (contamination) and identifies the chemicals reported as headspace constituents that may instead have been contaminants. Specific recommendations are given regarding the marking of certain chemicals as suspect on the basis they were sampling manifold contaminants.

  10. Headspace solid phase microextraction (HSSPME) for the determination of volatile and semivolatile pollutants in soils

    Energy Technology Data Exchange (ETDEWEB)

    Llompart, Maria [Departamento de Quimica Analitica Nutricion y Bromatologia, Facultad de Quimica, Universidad de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Li, Ken; Fingas, Merv [Emergencies Science Division, Environment Canada, Environmental Technology Centre, 3439 River Road, Ottawa, ON (Canada)

    1999-02-08

    We have investigated the use of headspace solid phase microextraction (HSSPME) as a sample concentration and preparation technique for the analysis of volatile and semivolatile pollutants in soil samples. Soil samples were suspended in solvent and the SPME fibre suspended in the headspace above the slurry. Finally, the fibre was desorbed in the Gas Chromatograph (GC) injection port and the analysis of the samples was carried out. Since the transfer of contaminants from the soil to the SPME fibre involves four separate phases (soil-solvent-headspace and fibre coating), parameters affecting the distribution of the analytes were investigated. Using a well-aged artificially spiked garden soil, different solvents (both organic and aqueous) were used to enhance the release of the contaminants from the solid matrix to the headspace. It was found that simple addition of water is adequate for the purpose of analysing the target volatile organic chemicals (VOCs) in soil. The addition of 1 ml of water to 1 g of soil yielded maximum response. Without water addition, the target VOCs were almost not released from the matrix and a poor response was observed. The effect of headspace volume on response as well as the addition of salt were also investigated. Comparison studies between conventional static headspace (HS) at high temperature (95C) and the new technology HSSPME at room temperature (=20C) were performed. The results obtained with both techniques were in good agreement. HSSPME precision and linearity were found to be better than automated headspace method and HSSPME also produced a significant enhancement in response. The detection and quantification limits for the target VOCs in soils were in the sub-ng g{sup -1} level. Finally, we tried to extend the applicability of the method to the analysis of semivolatiles. For these studies, two natural soils contaminated with diesel fuel and wood preservative, as well as a standard urban dust contaminated with polyaromatic

  11. COMPARISON OF VOLATILE COMPOUNDS IN TEUCRIUM POLIUM L. BY HEADSPACE AND HYDRODISTILLATION TECHNIQUES

    OpenAIRE

    2012-01-01

    Aerial parts of Teucrium polium were subjected to headspace (HS) and hydro-distillation (HD) techniques after drying, then headspace volatiles and the essential oil were analyzed by GC/MS. Forty-eight and Thirty-nine constituents were identified in hydro-distillation and CombiPAL system which represented 99.7% and 99.8% of the oils, respectively. hydro-distillation method were α-pinene (30.8%), β- pinene (12.0%), myrcene (8.9%), limonene (7.9%), (E)-caryophyllene (5.6%), Germacrene D (6.9%), ...

  12. A dynamical characterization of the uncertainty in projections of regional precipitation change in the semi-arid tropics

    Science.gov (United States)

    Giannini, A.

    2016-12-01

    The uncertainty in CMIP multi-model ensembles of regional precipitation change in tropical regions is well known: taken at face value, models do not agree on the direction of precipitation change. Consequently, in adaptation discourse, either projections are discounted, e.g., by giving more relevance to temperature projections, or outcomes are grossly misrepresented, e.g., in extrapolating recent drought into the long-term future. That this is an unsatisfactory state of affairs, given the dominant role of precipitation in shaping climate-sensitive human endeavors in the tropics, is an understatement.Here I will provide a dynamical characterization of the uncertainty in regional precipitation projections that exploits the CMIP multi-model ensembles. This characterization is based on decomposing the moisture budget and relating its terms to the influence of the oceans, specifically to the roles of moisture supply and stabilization of the vertical profile. I will discuss some preliminary findings highlighting the relevance of lessons learned from seasonal-to-interannual prediction. One such lesson is to go beyond the projection taken at face value, and understand physical processes, specifically, the role of the oceans, in order to be able to make qualitative arguments, in addition to quantitative predictions. One other lesson is to abandon the search for the "best model" and exploit the multi-model ensemble to characterize "emergent constraints".

  13. A progress report on the ARRA-funded geotechnical site characterization project

    Science.gov (United States)

    Martin, A. J.; Yong, A.; Stokoe, K.; Di Matteo, A.; Diehl, J.; Jack, S.

    2011-12-01

    For the past 18 months, the 2009 American Recovery and Reinvestment Act (ARRA) has funded geotechnical site characterizations at 189 seismographic station sites in California and the central U.S. This ongoing effort applies methods involving surface-wave techniques, which include the horizontal-to-vertical spectral ratio (HVSR) technique and one or more of the following: spectral analysis of surface wave (SASW), active and passive multi-channel analysis of surface wave (MASW) and passive array microtremor techniques. From this multi-method approach, shear-wave velocity profiles (VS) and the time-averaged shear-wave velocity of the upper 30 meters (VS30) are estimated for each site. To accommodate the variability in local conditions (e.g., rural and urban soil locales, as well as weathered and competent rock sites), conventional field procedures are often modified ad-hoc to fit the unanticipated complexity at each location. For the majority of sites (>80%), fundamental-mode Rayleigh wave dispersion-based techniques are deployed and where complex geology is encountered, multiple test locations are made. Due to the presence of high velocity layers, about five percent of the locations require multi-mode inversion of Rayleigh wave (MASW-based) data or 3-D array-based inversion of SASW dispersion data, in combination with shallow P-wave seismic refraction and/or HVSR results. Where a strong impedance contrast (i.e. soil over rock) exists at shallow depth (about 10% of sites), dominant higher modes limit the use of Rayleigh wave dispersion techniques. Here, use of the Love wave dispersion technique, along with seismic refraction and/or HVSR data, is required to model the presence of shallow bedrock. At a small percentage of the sites, surface wave techniques are found not suitable for stand-alone deployment and site characterization is limited to the use of the seismic refraction technique. A USGS Open File Report-describing the surface geology, VS profile and the

  14. Discrimination of Three Panax Species Based on Differences in Volatile Organic Compounds Using a Static Headspace GC-MS-Based Metabolomics Approach.

    Science.gov (United States)

    Chen, Xiao-Jia; Qiu, Jian-Feng; Wang, Yi-Tao; Wan, Jian-Bo

    2016-01-01

    Panax ginseng (Asian ginseng), Panax quinquefolium (American ginseng) and Panax notoginseng (notoginseng) are highly valuable tonic herbs derived from the Panax genus that have similar morphological appearances and odors but different pharmacological activities and clinical indications. Thus, the authentication of these three Panax species is crucial for ensuring the quality, safety and efficacy of medication. In the present study, a static headspace gas chromatography - mass spectrometry (GC-MS) followed by a multivariate statistical analysis was developed to globally characterize the volatile organic compound (VOC) profiles in P. ginseng, P. quinquefolium, and P. notoginseng, and subsequently to discover differentiating chemical markers. Under the optimized conditions, the headspace VOCs of a total of 49 batches of Panax herbs derived from the three Panax species were profiled, and the dataset of sample code, [Formula: see text]-m/z pair and ion intensity was processed by unsupervised principal component analysis (PCA) and by supervised partial least squared discriminant analysis (PLS-DA) to comprehensively compare the chemical differences in Panax across the species. The results demonstrated that Panax herbs derived from three species possess obviously diverse chemical characteristics of VOCs, PCA, and PLS-DA. According to their VOC profiles, 49 tested samples could be clearly differentiated according to species. Chemomarker 1, 2, and 4 might be used as unique chemical markers of P. ginseng, P. notoginseng and P. quinquefolium, respectively. Our findings indicate that static headspace GC-MS-based VOC profiling, combined with multivariate statistical analysis, provide a reliable tool to discriminate between the three Panax species and to identify their differentiation markers, which will be helpful for ensuring their quality, safety and efficacy.

  15. Greater Green River Basin production improvement project, Phase 1: Site characterization report

    Energy Technology Data Exchange (ETDEWEB)

    DeJarnett, B.B.; Krystinik, L.F.; Mead, R.H.; Poe, S.C.

    1996-05-01

    Several tight, naturally-fractured, gas-productive formations in the Greater Green River Basin (GGRB) in Wyoming have been exploited using conventional vertical well technology. Typically, hydraulic fracture treatments must be performed in completing these wells to increase gas production rates to economic levels. However, with the maturation of horizontal drilling technology hydraulic fracture treatments may not be the most effective method for improving gas production from these tight reservoirs. Two of the most prolific tight gas reservoirs in the Green River Basin, the Frontier and the Mesaverde, are candidates for the application of horizontal well completion technology. The objective of the proposed project is to apply the DOE`s technical concept to the Second Frontier Formation on the western flank of the Rock Springs Uplift. Previous industry attempts to produce in commercial quantities from the Second Frontier Formation have been hampered by lack of understanding of both the in-situ natural fracture system and lack of adequate stimulation treatments. The proposed technical approach involves drilling a vertical characterization well to the Second Frontier Formation at a depth of approximately 16,000 ft. from a site located about 18 miles northwest of Rock Springs, Wyoming. Logging, coring, and well testing information from the vertical well will be used to design a hydraulic fracturing treatment and to assess the resulting production performance. Data from the vertical drilling phase will be used to design a 2,500 to 3,000-ft lateral wellbore which will be kicked off from the vertical hole and extend into the blanket marine sandstone bench of the Second Frontier Formation. The trajectory of this wellbore will be designed to intersect the maximum number of natural fractures to maximize production rates. Production testing of the resulting completion will provide an assessment of reserve potential related to horizontal lateral completions.

  16. A strategy to seal exploratory boreholes in unsaturated tuff; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, J.A. [Sandia National Labs., Albuquerque, NM (United States); Case, J.B.; Givens, C.A.; Carney, B.C. [IT Corp., Albuquerque, NM (United States)

    1994-04-01

    This report presents a strategy for sealing exploratory boreholes associated with the Yucca Mountain Site Characterization Project. Over 500 existing and proposed boreholes have been considered in the development of this strategy, ranging from shallow (penetrating into alluvium only) to deep (penetrating into the groundwater table). Among the comprehensive list of recommendations are the following: Those boreholes within the potential repository boundary and penetrating through the potential repository horizon are the most significant boreholes from a performance standpoint and should be sealed. Shallow boreholes are comparatively insignificant and require only nominal sealing. The primary areas in which to place seals are away from high-temperature zones at a distance from the potential repository horizon in the Paintbrush nonwelded tuff and the upper portion of the Topopah Spring Member and in the tuffaceous beds of the Calico Hills Unit. Seals should be placed prior to waste emplacement. Performance goals for borehole seals both above and below the potential repository are proposed. Detailed construction information on the boreholes that could be used for future design specifications is provided along with a description of the environmental setting, i.e., the geology, hydrology, and the in situ and thermal stress states. A borehole classification scheme based on the condition of the borehole wall in different tuffaceous units is also proposed. In addition, calculations are presented to assess the significance of the boreholes acting as preferential pathways for the release of radionuclides. Design calculations are presented to answer the concerns of when, where, and how to seal. As part of the strategy development, available technologies to seal exploratory boreholes (including casing removal, borehole wall reconditioning, and seal emplacement) are reviewed.

  17. Phase 1 Characterization sampling and analysis plan West Valley demonstration project.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R. L. (Environmental Science Division)

    2011-06-30

    The Phase 1 Characterization Sampling and Analysis Plan (CSAP) provides details about environmental data collection that will be taking place to support Phase 1 decommissioning activities described in the Phase 1 Decommissioning Plan for the West Valley Demonstration Project, Revision 2 (Phase I DP; DOE 2009). The four primary purposes of CSAP data collection are: (1) pre-design data collection, (2) remedial support, (3) post-remediation status documentation, and (4) Phase 2 decision-making support. Data collection to support these four main objectives is organized into two distinct data collection efforts. The first is data collection that will take place prior to the initiation of significant Phase 1 decommissioning activities (e.g., the Waste Management Area [WMA] 1 and WMA 2 excavations). The second is data collection that will occur during and immediately after environmental remediation in support of remediation activities. Both data collection efforts have a set of well-defined objectives that encompass the data needs of the four main CSAP data collection purposes detailed in the CSAP. The main body of the CSAP describes the overall data collection strategies that will be used to satisfy data collection objectives. The details of pre-remediation data collection are organized by WMA. The CSAP contains an appendix for each WMA that describes the details of WMA-specific pre-remediation data collection activities. The CSAP is intended to expand upon the data collection requirements identified in the Phase 1 Decommissioning Plan. The CSAP is intended to tightly integrate with the Phase 1 Final Status Survey Plan (FSSP). Data collection described by the CSAP is consistent with the FSSP where appropriate and to the extent possible.

  18. Headspace Fourier transform infrared spectroscopy for the differentiation of Pandanus species.

    Science.gov (United States)

    Aganda, Kim Christopher C; Nonato, Maribel G; Sevilla, Fortunato; Santiago, Karen S

    2017-03-01

    Headspace Fourier Transform Infrared Spectroscopy (HS-FTIR) in tandem with chemometrics was applied to differentiate several species of the genus Pandanus. The headspace was generated from each Pandanus sample after incubation in a tightly sealed sample chamber. The resulting FTIR spectra of the headspace samples were found to be almost similar, but the application of principal component analysis (PCA) effectively differentiated the species. The unique spectral features for some samples were highlighted in the second-derivative FTIR spectra. A higher variance was exhibited in the PCA bi-plot of the 2nd derivative spectral data. The principal components differentiated not only the species, but also the cultivars or varieties, which formed distinct but proximate clusters. The manner of clustering obtained in this study resembled the behavior reported in a Random Amplified Polymorphic DNA analysis conducted on the Pandanus samples. The results demonstrate the potential of headspace FTIR spectroscopy as a simple, rapid, non-destructive, and relatively inexpensive method to discriminate between plant species and varieties.

  19. Flight attraction of Spodoptera littoralis (Lepidoptera, Noctuidae to cotton headspace and synthetic volatile blends

    Directory of Open Access Journals (Sweden)

    Felipe eBorrero-Echeverry

    2015-06-01

    Full Text Available The insect olfactory system discriminates odor signals of different biological relevance, which drive innate behavior. Identification of stimuli that trigger upwind flight attraction towards host plants is a current challenge, and is essential in developing new, sustainable plant protection methods, and for furthering our understanding of plant-insect interactions. Using behavioral, analytical and electrophysiological studies, we here show that both females and males of the Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera, Noctuidae, use blends of volatile compounds to locate their host plant, cotton, Gossypium hirsutum (Malvales, Malvaceae. Female S. littoralis were engaged in upwind orientation flight in a wind tunnel when headspace collected from cotton plants was delivered through a piezoelectric sprayer. Although males took off towards cotton headspace significantly fewer males than females flew upwind towards the sprayed headspace. Subsequent assays with antennally active synthetic compounds revealed that a blend of nonanal, (Z-3 hexenyl acetate, (E-β-ocimene, and (R-(+-limonene was as attractive as cotton headspace to females and more attractive to males. DMNT and (R-(--linalool, both known plant defense compounds may have reduced the flight attraction of both females and males; more moths were attracted to blends without these two compounds. Our findings provide a platform for further investigations on host plant signals mediating innate behavior, and for the development of novel insect plant protection strategies against S. littoralis.

  20. Volatile profile of yellow passion fruit juice by static headspace and solid phase microextraction techniques

    Directory of Open Access Journals (Sweden)

    Gilberto Costa Braga

    2015-02-01

    Full Text Available The profile of volatile compounds of yellow passion fruit juice was analyzed by solid phase microextraction headspace (HS-SPME and optimized static headspace (S-HS extraction techniques. Time, temperature, NaCl concentration and sample volume headspace equilibrium parameters was adjusted to the S-HS technique. The gaseous phase in the headspace of samples was collected and injected into a gas chromatograph coupled to a mass spectrometer. In the HS-SPME technique was identified 44 volatile compounds from the yellow passion fruit juice, but with S-HS only 30 compounds were identified. Volatile esters were majority in both techniques, being identified ethyl butanoate, ethyl hexanoate, (3z-3-hexenyl acetate, hexyl acetate, hexyl butanoate and hexyl hexanoate. Aldehydes and ketones were not identified in S-HS, but were in HS-SPME. β-Pinene, p-cymene, limonene, (Z-β-ocimene, (E-β-ocimene, γ-terpinene, α-terpinolene and (E -4,8-dimethyl-1, 3,7 - nonatriene terpenes were identified in both techniques. This study showed that the S-HS optimized extraction technique was effective to recovery high concentrations of the major volatile characteristics compounds in the passion fruit, such as ethyl butanoate and ethyl hexanoate, which can be advantageous due to the simplicity of the method.

  1. Bacterial bioremediation of selenium oxyanions using a dynamic flow bioreactor and headspace analysis

    Energy Technology Data Exchange (ETDEWEB)

    McCarty, S.L.; Chasteen, T.G. [Sam Houston State Univ., Huntsville, TX (United States). Dept. of Chemistry; Stalder, V.; Bachofen, R. [Univ. of Zuerich (Switzerland). Inst. of Plant Biology

    1995-12-31

    The volatile products of the biological reduction and methylation of selenium`s most common oxyanions, selenate and selenite, were determined using capillary gas chromatography and fluorine-induced chemiluminescence detection. Dimethyl selenide and dimethyl diselenide were detected in the headspace above cultures of bacteria resistant to this metalloid using static and dynamic headspace sampling techniques. Fluorine-induced chemiluminescence detection was applied to determine the relative concentrations of the organosulfur and organoselenium species released over many days of culture growth at a controlled temperature and purge rate. A selenium-resistant bacterium, Pseudomonas fluorescens K27, and a phototrophic bacterium Rhodobacter sphaeroides 2.4.1 were exposed to SeO{sub 4}{sup 2{minus}}, and the cultures` headspaces were examined over a period of several days for volatile selenium-containing products. The results show that the relative production of the volatile species over time depicts a pattern generally independent of the growth phase in the case of the phototrophic bacterium; the concentrations of metabolic dimethyl sulfide and dimethyl selenide determined in static headspace were highest after the microbe had been in stationary phase for 4 days.

  2. Subsurface Access, Characterization, Acquisition, Transport, Storage and Delivery in Microgravity Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will develop geotechnical measurements, sample extraction and transport equipment for subsurface regolith on NEOs, asteroids, moons and planets,...

  3. Final report on the Background Soil Characterization Project at the Oak Ridge Reservation, Oak Ridge, Tennessee. Volume 2: Data

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    The Background Soil Characterization Project (BSCP) will provide background concentration levels of selected metals organic compounds, and radionuclides in soils from uncontaminated on-site areas at the Oak Ridge Reservation (ORR), and off-site in the western part of Roane County and the eastern part of Anderson County. The BSCP will establish a database, recommend how to use the data for contaminated site assessment, and provide estimates of the potential human health and environmental risks associated with the background level concentrations of potentially hazardous constituents. This volume contains the data from the Background Soil Characterization Project. When available, the following validation qualifiers are used in the appendixes. When validation qualifiers are not available, the corresponding contract laboratory data qualifiers appearing on the next page are used.

  4. Remote sensing data exploiration for geologic characterization of difficult targets : Laboratory Directed Research and Development project 38703 final report.

    Energy Technology Data Exchange (ETDEWEB)

    Costin, Laurence S.; Walker, Charles A.; Lappin, Allen R.; Hayat, Majeed M. (University of New Mexico, Albuquerque, NM); Ford, Bridget K.; Paskaleva, Biliana (University of New Mexico, Albuquerque, NM); Moya, Mary M.; Mercier, Jeffrey Alan (University of Arizona, Tucson, AZ); Stormont, John C. (University of New Mexico, Albuquerque, NM); Smith, Jody Lynn

    2003-09-01

    Characterizing the geology, geotechnical aspects, and rock properties of deep underground facility sites can enhance targeting strategies for both nuclear and conventional weapons. This report describes the results of a study to investigate the utility of remote spectral sensing for augmenting the geological and geotechnical information provided by traditional methods. The project primarily considered novel exploitation methods for space-based sensors, which allow clandestine collection of data from denied sites. The investigation focused on developing and applying novel data analysis methods to estimate geologic and geotechnical characteristics in the vicinity of deep underground facilities. Two such methods, one for measuring thermal rock properties and one for classifying rock types, were explored in detail. Several other data exploitation techniques, developed under other projects, were also examined for their potential utility in geologic characterization.

  5. Effects of headspace and oxygen level on off-gas emissions from wood pellets in storage.

    Science.gov (United States)

    Kuang, Xingya; Shankar, Tumuluru Jaya; Sokhansanj, Shahab; Lim, C Jim; Bi, Xiaotao T; Melin, Staffan

    2009-11-01

    Few papers have been published in the open literature on the emissions from biomass fuels, including wood pellets, during the storage and transportation and their potential health impacts. The purpose of this study is to provide data on the concentrations, emission factors, and emission rate factors of CO(2), CO, and CH(4) from wood pellets stored with different headspace to container volume ratios with different initial oxygen levels, in order to develop methods to reduce the toxic off-gas emissions and accumulation in storage spaces. Metal containers (45 l, 305 mm diameter by 610 mm long) were used to study the effect of headspace and oxygen levels on the off-gas emissions from wood pellets. Concentrations of CO(2), CO, and CH(4) in the headspace were measured using a gas chromatograph as a function of storage time. The results showed that the ratio of the headspace ratios and initial oxygen levels in the storage space significantly affected the off-gas emissions from wood pellets stored in a sealed container. Higher peak emission factors and higher emission rates are associated with higher headspace ratios. Lower emissions of CO(2) and CO were generated at room temperature under lower oxygen levels, whereas CH(4) emission is insensitive to the oxygen level. Replacing oxygen with inert gases in the storage space is thus a potentially effective method to reduce the biomass degradation and toxic off-gas emissions. The proper ventilation of the storage space can also be used to maintain a high oxygen level and low concentrations of toxic off-gassing compounds in the storage space, which is especially useful during the loading and unloading operations to control the hazards associated with the storage and transportation of wood pellets.

  6. Subsurface Characterization and Seismic Monitoring for the Southwest Partnerships Phase III Demonstration Project at Farnsworth Field, TX

    Science.gov (United States)

    Will, R. A.; Balch, R. S.

    2015-12-01

    The Southwest Partnership on Carbon Sequestration is performing seismic based characterization and monitoring activities at an active CO2 EOR project at Farnsworth Field, Texas. CO2 is anthropogenically sourced from a fertilizer and an ethanol plant. The field has 13 CO2 injectors and has sequestered 302,982 metric tonnes of CO2 since October 2013. The field site provides an excellent laboratory for testing a range of monitoring technologies in an operating CO2 flood since planned development is sequential and allows for multiple opportunities to record zero CO2 baseline data, mid-flood data, and fully flooded data. The project is comparing and contrasting several scales of seismic technologies in order to determine best practices for large scale commercial sequestration projects. Characterization efforts include an 85 km2 3D surface seismic survey, baseline and repeat 3D VSP surveys centered on injection wells, cross-well tomography baseline and repeat surveys between injector/producer pairs, and a borehole passive seismic array to monitor induced seismicity. All surveys have contributed to detailed geologic models which were then used for fluid flow and risk assessment simulations. 3D VSP and cross-well data with repeat surveys have allowed for direct comparisons of the reservoir prior to CO2 injection and at eight months into injection, with a goal of imaging the CO2 plume as it moves away from injection wells. Additional repeat surveys at regular intervals will continue to refine the plume. The goal of this work is to demonstrate seismic based technologies to monitor CO2 sequestration projects, and to contribute to best practices manuals for commercial scale CO2 sequestration projects. In this talk the seismic plan will be outlined, progress towards goals enumerated, and preliminary results from baseline and repeat seismic data will be discussed. Funding for this project is provided by the U.S. Department of Energy under Award No. DE-FC26-05NT42591.

  7. Characterizing Cross-Professional Collaboration in Research and Development Projects in Secondary Education

    Science.gov (United States)

    Schenke, Wouter; van Driel, Jan H.; Geijsel, Femke P.; Sligte, Henk W.; Volman, Monique L. L.

    2016-01-01

    Collaboration between practitioners and researchers can increasingly be observed in research and development (R&D) projects in secondary schools. This article presents an analysis of cross-professional collaboration between teachers, school leaders and educational researchers and/or advisers as part of R&D projects in terms of three…

  8. Fuel Thermo-physical Characterization Project. Fiscal Year 2014 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Burkes, Douglas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Andrew M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Amanda J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Edwards, Matthew K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); MacFarlan, Paul J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pool, Karl N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Slonecker, Bruce D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smith, Frances N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Steen, Franciska H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-15

    The Office of Material Management and Minimization (M3) Reactor Conversion Fuel Thermo-Physical Characterization Project at Pacific Northwest National Laboratory (PNNL) was tasked with using PNNL facilities and processes to receive irradiated low enriched uranium–molybdenum (LEU-Mo) fuel plate samples and perform analysis in support of the M3 Reactor Conversion Program. This work is in support of the M3 Reactor Conversion Fuel Development Pillar that is managed by Idaho National Laboratory. The primary research scope was to determine the thermo-physical properties as a function of temperature and burnup. Work conducted in Fiscal Year (FY) 2014 complemented measurements performed in FY 2013 on four additional irradiated LEU-Mo fuel plate samples. Specifically, the work in FY 2014 investigated the influence of different processing methods on thermal property behavior, the absence of aluminum alloy cladding on thermal property behavior for additional model validation, and the influence of higher operating surface heat flux / more aggressive irradiation conditions on thermal property behavior. The model developed in FY 2013 and refined in FY 2014 to extract thermal properties of the U-Mo alloy from the measurements conducted on an integral fuel plate sample (i.e., U-Mo alloy with a thin Zr coating and clad in AA6061) continues to perform very well. Measurements conducted in FY 2014 on samples irradiated under similar conditions compare well to measurements performed in FY 2013. In general, there is no gross influence of fabrication method on thermal property behavior, although the difference in LEU-Mo foil microstructure does have a noticeable influence on recrystallization of grains during irradiation. Samples irradiated under more aggressive irradiation conditions, e.g., higher surface heat flux, revealed lower thermal conductivity when compared to samples irradiated at moderate surface heat fluxes, with the exception of one sample. This report documents thermal

  9. Tank 241-TY-104 vapor sampling and analysis tank characterization report

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, J.L.

    1995-05-31

    This report presents the details of the Hanford waste tank characterization study for tank 241-TY-104. The drivers and objectives of the headspace vapor sampling and analysis were in accordance with procedures that were presented in other reports. The vapor and headspace gas samples were collected and analyzed to determine the potential risks to tank farm workers due to fugitive emissions from the tank.

  10. Analysis of volatile organic compounds in pleural effusions by headspace solid-phase microextraction coupled with cryotrap gas chromatography and mass spectrometry.

    Science.gov (United States)

    Huang, Zhongping; Zhang, Jie; Zhang, Peipei; Wang, Hong; Pan, Zaifa; Wang, Lili

    2016-07-01

    Headspace solid-phase microextraction coupled with cryotrap gas chromatography and mass spectrometry was applied to the analysis of volatile organic compounds in pleural effusions. The highly volatile organic compounds were separated successfully with high sensitivity by the employment of a cryotrap device, with the construction of a cold column head by freezing a segment of metal capillary with liquid nitrogen. A total of 76 volatile organic compounds were identified in 50 pleural effusion samples (20 malignant effusions and 30 benign effusions). Among them, 34 more volatile organic compounds were detected with the retention time less than 8 min, by comparing with the normal headspace solid-phase microextraction coupled with gas chromatography and mass spectrometry method. Furthermore, 24 volatile organic compounds with high occurrence frequency in pleural effusion samples, 18 of which with the retention time less than 8 min, were selected for the comparative analysis. The results of average peak area comparison and box-plot analysis showed that except for cyclohexanone, 2-ethyl-1-hexanol, and tetramethylbenzene, which have been reported as potential cancer biomarkers, cyclohexanol, dichloromethane, ethyl acetate, n-heptane, ethylbenzene, and xylene also had differential expression between malignant and benign effusions. Therefore, the proposed approach was valuable for the comprehensive characterization of volatile organic compounds in pleural effusions.

  11. Engineered Materials Characterization Report for the Yucca Mountain Site Characterization Project, Volume 3, Revision 1, Corrosion Data and Modeling

    Energy Technology Data Exchange (ETDEWEB)

    McCright, R D

    1998-04-01

    The Engineered Materials Characterization Report (EMCR) serves as a source of information on the properties of materials proposed as elements in the engineered barrier system (EBS) for the Yucca Mountain nuclear waste repository. Volume 3 covered the corrosion data and modeling efforts. The present report is a revision to Volume 3 and updates information on the corrosion (and other degradation modes) behavior of candidate materials for the various components of the EBS. It also includes work on the performance modeling of these materials. Work is reported on metallic barriers, basket materials, packing/backfill/invert materials, and non-metallic materials.

  12. Geotechnical characterization of the North Ramp of the Exploratory Studies Facility: Yucca Mountain Site Characterization Project. Volume 2, NRG corehole data appendices

    Energy Technology Data Exchange (ETDEWEB)

    Brechtel, C.E.; Lin, Ming; Martin, E. [Agapito Associates, Inc., Grand Junction, CO (United States); Kessel, D.S. [Sandia National Labs., Albuquerque, NM (United States)

    1995-05-01

    This report presents the results of the geological and geotechnical characterization of the Miocene volcanic tuff rocks of the Timber Mountain and Paintbrush groups that the tunnel boring machine will encounter during excavations of the Exploratory Studies Facility (ESF) North Ramp. The information in this report was developed to support the design of the ESF North Ramp. The ESF is being constructed by the DOE as part of the Yucca Mountain Project site characterization activities. The purpose of these activities is to evaluate the potential to locate the national high-level nuclear waste repository on land within and adjacent to the Nevada Test Site (NTS), Nye County, Nevada. This report was prepared as part of the Soil and Rock Properties Studies in accordance with the 8.3.1.14.2 Study Plan to Provide Soil and Rock Properties. This is volume 2 which contains NRG Corehole Data for each of the NRG Holes.

  13. Characterization, Monitoring, and Risk Assessment at the IEA GHG Weyburn-Midale CO2 Monitoring and Storage Project, Saskatchewan, Canada.

    Science.gov (United States)

    Ben, R.; Chalaturnyk, R.; Gardner, C.; Hawkes, C.; Johnson, J.; White, D.; Whittaker, S.

    2008-12-01

    In July 2000, a major research project was initiated to study the geological storage of CO2 as part of a 5000 tonnes/day EOR project planned for the Weyburn Field in Saskatchewan, Canada. Major objectives of the IEA GHG Weyburn CO2 monitoring and storage project included: assessing the integrity of the geosphere encompassing the Weyburn oil pool for effective long-term storage of CO2; monitoring the movement of the injected CO2, and assessing the risk of migration of CO2 from the injection zone (approximately 1500 metres depth) to the surface. Over the period 2000-2004, a diverse group of 80+ researchers worked on: geological, geophysical, and hydrogeological characterizations at both the regional (100 km beyond the field) and detailed scale (10 km around the field); conducted time-lapse geophysical surveys; carried out surface and subsurface geochemical surveys; and undertook numerical reservoir simulations. Results of the characterization were used for a performance assessment that concluded the risk of CO2 movement to the biosphere was very small. By September 2007, more than 14 Mtonnes of CO2 had been injected into the Weyburn reservoir, including approximately 3 Mtonnes recycled from oil production. A "Final Phase" research project was initiated (2007- 2011) to contribute to a "Best Practices" guide for long-term CO2 storage in EOR settings. Research objectives include: improving the geoscience characterization; further detailed analysis and data collection on the role of wellbores; additional geochemical and geophysical monitoring activities; and an emphasis on quantitative risk assessments using multiple analysis techniques. In this talk a review of results from Phase I will be presented followed by plans and initial results for the Final Phase.

  14. Process-Hardened, Multi-Analyte Sensor for Characterizing Rocket Plum Constituents Under Test Environment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This STTR project aims to develop a process-hardened, simple and low cost multi-analyte sensor for detecting components of rocket engine plumes. The sensor will be...

  15. Blade Vibration Measurement System for Characterization of Closely Spaced Modes and Mistuning Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phase I project successfully demonstrated that the advanced non-contacting stress measurement system (NSMS) was able to address closely spaced modes and...

  16. Process-Hardened, Multi-Analyte Sensor for Characterizing Rocket Plum Constituents Under Test Environment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the Phase II STTR project is to develop a prototype multi-analyte sensor system to detect gaseous analytes present in the test stands during...

  17. Effect of Subcritical Fluid Extraction on the High Quality of Headspace Oil from Jasminum sambac (L.) Aiton.

    Science.gov (United States)

    Ye, Qiuping; Jin, Xinyi; Wei, Shiqin; Zheng, Gongyu; Li, Xinlei

    2016-05-01

    Subcritical fluid extraction (SFE), as a novel method, was applied to investigate the yield, quality, and sensory evaluation of headspace oil from Jasminum sambac (L.) Aiton in comparison with petroleum ether extraction (PEE). The results indicated that the yield of the headspace oil using SFE was significantly higher (P < 0.05) than when using PEE. SFE contributed to obtaining alcohols and ethers, prevented the thermal reaction of terpenes, and reduced α-caryophyllene and β-caryophyllene in the headspace oil. The contents of linalool (21.90%) and benzyl acetate (16.31%) were higher via SFE than PEE. In addition, the sensory evaluation of SFE was superior to PEE, indicating a fresh, jasmine-like odor and green-yellow color. Thus, SFE is an improved method for obtaining natural headspace oil from jasmine flowers.

  18. Effect of Subcritical Fluid Extraction on the High Quality of Headspace Oil from Jasminum sambac (L.) Aiton.

    Science.gov (United States)

    2016-04-22

    Subcritical fluid extraction (SFE), as a novel method, was applied to investigate the yield, quality, and sensory evaluation of headspace oil from Jasminum sambac (L.) Aiton in comparison with petroleum ether extraction (PEE). The results indicated that the yield of the headspace oil using SFE was significantly higher (P < 0.05) than when using PEE. SFE contributed to obtaining alcohols and ethers, prevented the thermal reaction of terpenes, and reduced α-caryophyllene and β-caryophyllene in the headspace oil. The contents of linalool (21.90%) and benzyl acetate (16.31%) were higher via SFE than PEE. In addition, the sensory evaluation of SFE was superior to PEE, indicating a fresh, jasmine-like odor and green-yellow color. Thus, SFE is an improved method for obtaining natural headspace oil from jasmine flowers.

  19. Effect of ethanol, temperature, and gas flow rate on volatile release from aqueous solutions under dynamic headspace dilution conditions.

    Science.gov (United States)

    Tsachaki, Maroussa; Gady, Anne-Laure; Kalopesas, Michalis; Linforth, Robert S T; Athès, Violaine; Marin, Michele; Taylor, Andrew J

    2008-07-09

    On the basis of a mechanistic model, the overall and liquid mass transfer coefficients of aroma compounds were estimated during aroma release when an inert gas diluted the static headspace over simple ethanol/water solutions (ethanol concentration = 120 mL x L(-1)). Studied for a range of 17 compounds, they were both increased in the ethanol/water solution compared to the water solution, showing a better mass transfer due to the presence of ethanol, additively to partition coefficient variation. Thermal imaging results showed differences in convection of the two systems (water and ethanol/water) arguing for ethanol convection enhancement inside the liquid. The effect of ethanol in the solution on mass transfer coefficients at different temperatures was minor. On the contrary, at different headspace dilution rates, the effect of ethanol in the solution helped to maintain the volatile headspace concentration close to equilibrium concentration, when the headspace was replenished 1-3 times per minute.

  20. Time since discharge of 9mm cartridges by headspace analysis, part 1: Comprehensive optimisation and validation of a headspace sorptive extraction (HSSE) method.

    Science.gov (United States)

    Gallidabino, M; Romolo, F S; Weyermann, C

    2017-03-01

    Estimating the time since discharge of spent cartridges can be a valuable tool in the forensic investigation of firearm-related crimes. To reach this aim, it was previously proposed that the decrease of volatile organic compounds released during discharge is monitored over time using non-destructive headspace extraction techniques. While promising results were obtained for large-calibre cartridges (e.g., shotgun shells), handgun calibres yielded unsatisfying results. In addition to the natural complexity of the specimen itself, these can also be attributed to some selective choices in the methods development. Thus, the present series of paper aimed to more systematically evaluate the potential of headspace analysis to estimate the time since discharge of cartridges through the use of more comprehensive analytical and interpretative techniques. Specifically, in this first part, a method based on headspace sorptive extraction (HSSE) was comprehensively optimised and validated, as the latter recently proved to be a more efficient alternative than previous approaches. For this purpose, 29 volatile organic compounds were preliminary selected on the basis of previous works. A multivariate statistical approach based on design of experiments (DOE) was used to optimise variables potentially involved in interaction effects. Introduction of deuterated analogues in sampling vials was also investigated as strategy to account for analytical variations. Analysis was carried out by selected ion mode, gas chromatography coupled to mass spectrometry (GC-MS). Results showed good chromatographic resolution as well as detection limits and peak area repeatability. Application to 9mm spent cartridges confirmed that the use of co-extracted internal standards allowed for improved reproducibility of the measured signals. The validated method will be applied in the second part of this work to estimate the time since discharge of 9mm spent cartridges using multivariate models.

  1. Differentiating organically and conventionally grown oregano using ultraperformance liquid chromatography mass spectrometry (UPLC-MS), headspace gas chromatography with flame ionization detection (headspace-GC-FID), and flow injection mass spectrum (FIMS) fingerprints combined with multivariate data analysis.

    Science.gov (United States)

    Gao, Boyan; Qin, Fang; Ding, Tingting; Chen, Yineng; Lu, Weiying; Yu, Liangli Lucy

    2014-08-13

    Ultraperformance liquid chromatography mass spectrometry (UPLC-MS), flow injection mass spectrometry (FIMS), and headspace gas chromatography (headspace-GC) combined with multivariate data analysis techniques were examined and compared in differentiating organically grown oregano from that grown conventionally. It is the first time that headspace-GC fingerprinting technology is reported in differentiating organically and conventionally grown spice samples. The results also indicated that UPLC-MS, FIMS, and headspace-GC-FID fingerprints with OPLS-DA were able to effectively distinguish oreganos under different growing conditions, whereas with PCA, only FIMS fingerprint could differentiate the organically and conventionally grown oregano samples. UPLC fingerprinting provided detailed information about the chemical composition of oregano with a longer analysis time, whereas FIMS finished a sample analysis within 1 min. On the other hand, headspace GC-FID fingerprinting required no sample pretreatment, suggesting its potential as a high-throughput method in distinguishing organically and conventionally grown oregano samples. In addition, chemical components in oregano were identified by their molecular weight using QTOF-MS and headspace-GC-MS.

  2. Geochemistry of drill core headspace gases and its significance in gas hydrate drilling in Qilian Mountain permafrost

    Science.gov (United States)

    Lu, Zhengquan; Rao, Zhu; He, Jiaxiong; Zhu, Youhai; Zhang, Yongqin; Liu, Hui; Wang, Ting; Xue, Xiaohua

    2015-02-01

    Headspace gases from cores are sampled in the gas hydrate drilling well DK-8 in the Qilian Mountain permafrost. Gas components and carbon isotopes of methane from headspace gas samples are analyzed. The geochemical features of the headspace gases along the well profile are compared with occurrences of gas hydrate, and with the distribution of faults or fractures. Their geochemical significance is finally pointed out in gas hydrate occurrences and hydrocarbon migration. Results show high levels of hydrocarbon concentrations in the headspace gases at depths of 149-167 m, 228-299 m, 321-337 m and 360-380 m. Visible gas hydrate and its associated anomalies occur at 149-167 m and 228-299 m; the occurrence of high gas concentrations in core headspace gases was correlated to gas hydrate occurrences and their associated anomalies, especially in the shallow layers. Gas compositions, gas ratios of C1/ΣC1-5, C1/(C2 + C3), iC4/nC4, and iC5/nC5, and carbon isotopic compositions of methane (δ13C1, PDB‰) indicate that the headspace gases are mainly thermogenic, partly mixed with biodegraded thermogenic sources with small amounts derived from microbial sources. Faults or fracture zones are identified at intervals of 149-167 m, 228-299 m, 321-337 m, and near 360-380 m; significantly higher gas concentrations and lower dryness ratio were found in the headspace gases within the fault or fracture zones compared with areas above these zones. In the shallow zones, low dryness ratios were observed in headspace gases in zones where gas hydrate and faults or fracture zones were found, suggesting that faults or fracture zones serve as migration paths for gases in the deep layers and provide accumulation space for gas hydrate in the shallow layers of the Qilian Mountain permafrost.

  3. Final work plan: Expedited Site Characterization of the IES Industries, Inc., Site at Marshalltown, Iowa. Ames Expedited Site Characterization Project, Version 1.0

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-04

    The overall goal of the Ames Laboratory Expedited Site Characterization (ESC) project is to evaluate and promote both innovative and state-of-the-practice site characterization and/or monitoring technologies. This will be accomplished by fielding both types of technologies together in the context of an expedited site characterization. The first site will be at a former manufactured gas plant (FMGP) in Marshalltown, Iowa. The project will field three areas of technology: geophysical, analytical, and data fusion. Geophysical technologies are designed to understand the subsurface geology to help predict fate and transport of the target contaminants. Analytical technologies/methods are designed to detect and quantify the target contaminants. Data fusion technology consists of software systems designed to rapidly integrate or fuse all site information into a conceptual site model that then becomes the decision making tool for the site team to plan subsequent sampling activity. Not all of the contaminants present can be located at the action level. Polynuclear aromatic hydrocarbons (PAHs) are the signature organics associated with the coal tar activities that took place at the site. As a result, PAHs were selected as the target compounds. Screening analytical instruments and nonintrusive geophysical techniques will be fielded to qualitatively map the spatial contaminant distribution. Soil gas surveys, immunoassay testing (IMA), innovative optical techniques, and passive organic sorbent sensors will be deployed along with the geophysical methods. Gas chromatography/mass spectrometry (GC/MS) instruments and a cone penetrometer system equipped with a laser-induced fluorescence (LIF) probe will quantitatively map the action level edges of the PAH plume(s). Samples will be taken both by the cone penetrometer test system (CPT) and the Geoprobe {reg_sign} sampler system.

  4. Final report for the Iowa Livestock Industry Waste Characterization and Methane Recovery Information Dissemination Project

    Energy Technology Data Exchange (ETDEWEB)

    Garrison, M.V.; Richard, Thomas L

    2001-11-13

    This report summarizes analytical methods, characterizes Iowa livestock wastes, determines fossil fuel displacement by methane use, assesses the market potential, and offers recommendations for the implementation of methane recovery technologies.

  5. Multi-Use Non-Intrusive Flow Characterization System (FCS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The product of the Phase II effort will be a Multi-Use Non-Intrusive Flow Characterization System (FCS) for densified, normal boiling point, and two-phase cryogenic...

  6. Multi-Use Non-Intrusive Flow Characterization System (FCS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation is a Multi-Use Non-Intrusive Flow Characterization System (FCS) for densified, normal boiling point, and two-phase cryogenic flows, capable of...

  7. Biomonitoring of benzene and toluene in human blood by headspace-solid-phase microextraction

    Energy Technology Data Exchange (ETDEWEB)

    Schimming, E.; Levsen, K. [Fraunhofer-Institut fuer Toxikologie und Aerosolforschung (ITA), Hannover (Germany); Koehme, C.; Schuermann, W. [Medizinische Hochschule Hannover (Germany). Abt. fuer Pneumologie

    1999-01-01

    A simple and rapid method for the determination of benzene and toluene in whole blood by headspace-solid-phase microextraction (HS-SPME) is described. Using SPME fibres coated with 65 {mu}m carboxene/polydimethylsiloxane, limits of quantification (LOQ) of 5 ng/L for benzene and 25 ng/L for toluene are achieved. As a result of its large linear range (i.e. 5-5000 ng/L for benzene) the method is suitable for biomonitoring of both occupationally and environmentally exposed people. The reproducibility of the determination of benzene is {<=} 8%. An interlaboratory comparison demonstrated that the method proposed here compares favorably with existing methods (dynamic headspace, purge and trap). (orig.) With 2 figs., 2 tabs., 10 refs.

  8. Simultaneous Determination of Alkoxyalcohols in Wet Wipes Using Static Headspace Gas Chromatography and Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lee, So Jin; Pyo, Hee Soo; Chung, Bong Chul; Lee, Jeon Gae [KIST, Seoul (Korea, Republic of); Kim, Hai Dong [Kyung Hee University, Seoul (Korea, Republic of)

    2014-09-15

    Alkoxyalcohols are used as solvents or preservatives in various consumer products such as wet wipes. The metabolites of alkoxyalcohols are known to be chronically toxic and carcinogenic to animals. Thus, an analytical method is needed to monitor alkoxyalcohols in wet wipes. The aim of this study was to develop a simultaneous analytical method for 14 alkoxyalcohols using headspace gas chromatography coupled with mass spectrometry to analyze the wet wipes. This method was developed by comparing with various headspace extraction parameters. The linear calibration curves were obtained for the method (r2 > 0.995). The limit of detection of alkoxyalcohols ranged from 2 to 200 ng mL-1. The precision of the determinative method was less than 18.20% coefficient of variation both intra and inter days. The accuracy of the method ranged from 82.86% to 119.83%. (2-Methoxymethylethoxy)propanol, 2-phenoxyethanol, and 1-phenoxy-2-propanol were mainly detected in wet wipes.

  9. Teaching Protein Purification and Characterization Techniques: A Student-Initiated, Project-Oriented Biochemistry Laboratory Course

    Science.gov (United States)

    MacDonald, Gina

    2008-01-01

    This report describes a biochemistry laboratory that is completely project-oriented. Upper-level biology and chemistry majors work in teams to purify a protein of their choice. After the student groups have completed literature searches, ordered reagents, and made buffers they continue to learn basic protein purification and biochemical techniques…

  10. Selective fiber used for headspace solid-phase microextraction of abused drugs in human urine

    OpenAIRE

    Sunanta Wangkarn

    2007-01-01

    A sensitive and selective fiber for simultaneous analysis of three drugs of abuse (amphetamine, methamphetamine and ephedrine) in urine samples was explored using headspace solid phase microextraction and gas chromatography with flame ionization detection. Several parameters affecting extraction such as extraction time, extraction temperature, pH of solution and salt concentrations were investigated. Among five commercially available fibers, divinylbenzene/carboxen/ polydimethylsiloxane is th...

  11. Determination of volatile organic compounds in water using headspace knotted hollow fiber microextraction.

    Science.gov (United States)

    Chen, Pai-Shan; Tseng, Yu-Hsiang; Chuang, Yuh-Lin; Chen, Jung-Hsuan

    2015-05-22

    An efficient and effective headspace microextraction technique named static headspace knotted hollow fiber microextraction (HS-K-HFME) has been developed for the determination of volatile organic compounds (VOCs) in water samples. The knot-shaped hollow fiber is filled with 25μL of the extraction solvent. The excess solvent forms a large droplet (13μL) and is held in the center of the knot. Even after 20min of extraction time at high temperature (95°C) without cooling, there was still enough volume of extraction solvent for gas chromatography-mass spectrometry (GC-MS) analysis, which extends the choice of solvents for headspace LPME. Moreover, the knot-shaped fiber has a larger extraction contact interface, which increases the rate of mass transfer between the headspace and extraction solvent film attached to the fiber, thus improving the extraction efficiency. The effects of extraction solvent, temperature, stirring rate, salt concentration and extraction time on extraction performance were optimized. The calibration curves exhibited coefficients of determination (R(2)) ranging from 0.9957 to 0.9999 and the limit of detection (LOD) ranged from 0.2 to 10μgL(-1). Relative standard deviations (RSDs) ranged from 4.5% to 11.6% for intraday measurements (n=5). Interday (n=15) values were between 2.2% and 12.9%. The relative recoveries (RRs) ranged from 90.3% to 106.0% for river water and 95.9% to 103.6% for wastewater.

  12. Evaluation of noni (Morinda citrifolia) volatile profile by dynamic headspace and gas chromatography-mass spectrometry

    OpenAIRE

    Sousa, A.; M. A. SOUZA NETO; GARRUTI, D. dos S.; Sousa, J. A.; BRITO, E. S. de

    2010-01-01

    Noni is a fruit that has interested the scientific community due to its medicinal and functional activities. Different products that contain noni are already in the market, but their consumption could be impaired by their distinctive unpleasant aroma and flavor. The aim of this work was to evaluate the noni pulp volatile profile by dynamic headspace and gas chromatography-mass spectrometry. Thirty seven volatile compounds were detected, mainly alcohols (63.3%), esters (26.9%), cetones (7.4%),...

  13. Site characterization report for the basalt waste isolation project. Volume II

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-11-01

    The reference location for a repository in basalt for the terminal storage of nuclear wastes on the Hanford Site and the candidate horizons within this reference repository location have been identified and the preliminary characterization work in support of the site screening process has been completed. Fifteen technical questions regarding the qualification of the site were identified to be addressed during the detailed site characterization phase of the US Department of Energy-National Waste Terminal Storage Program site selection process. Resolution of these questions will be provided in the final site characterization progress report, currently planned to be issued in 1987, and in the safety analysis report to be submitted with the License Application. The additional information needed to resolve these questions and the plans for obtaining the information have been identified. This Site Characterization Report documents the results of the site screening process, the preliminary site characterization data, the technical issues that need to be addressed, and the plans for resolving these issues. Volume 2 contains chapters 6 through 12: geochemistry; surface hydrology; climatology, meteorology, and air quality; environmental, land-use, and socioeconomic characteristics; repository design; waste package; and performance assessment.

  14. Simultaneous Determination of Benzene and Toluene in Pesticide Emulsifiable Concentrate by Headspace GC-MS

    Directory of Open Access Journals (Sweden)

    Lidong Cao

    2013-01-01

    Full Text Available The toxic inert ingredients in pesticide formulations are strictly regulated in many countries. In this paper, a simple and efficient headspace-gas chromatography-mass spectrometry (HSGC-MS method using fluorobenzene as an internal standard (IS for rapid simultaneous determination of benzene and toluene in pesticide emulsifiable concentrate (EC was established. The headspace and GC-MS conditions were investigated and developed. A nonpolar fused silica Rtx-5 capillary column (30 m×0.20 mm i.d. and 0.25 μm film thickness with temperature programming was used. Under optimized headspace conditions, equilibration temperature of 120°C, equilibration time of 5 min, and sample size of 50 μL, the regression of the peak area ratios of benzene and toluene to IS on the concentrations of analytes fitted a linear relationship well at the concentration levels ranging from 3.2 g/L to 16.0 g/L. Standard additions of benzene and toluene to blank different matrix solutions 1ead to recoveries of 100.1%–109.5% with a relative standard deviation (RSD of 0.3%–8.1%. The method presented here stands out as simple and easily applicable, which provides a way for the determination of toxic volatile adjuvant in liquid pesticide formulations.

  15. Headspace liquid-phase microextraction of methamphetamine and amphetamine in urine by an aqueous drop

    Energy Technology Data Exchange (ETDEWEB)

    He Yi [Department of Sciences, John Jay College of Criminal Justice, City University of New York, 445 W 59th Street, New York, NY 10019 (United States)]. E-mail: yhe@jjay.cuny.edu; Vargas, Angelica [Department of Sciences, John Jay College of Criminal Justice, City University of New York, 445 W 59th Street, New York, NY 10019 (United States); Kang, Youn-Jung [Department of Sciences, John Jay College of Criminal Justice, City University of New York, 445 W 59th Street, New York, NY 10019 (United States)

    2007-04-25

    This study developed a headspace liquid-phase microextraction (LPME) method by using a single aqueous drop in combination with high performance liquid chromatography (HPLC)-UV detection for the determination of methamphetamine (MAP) and amphetamine (AP) in urine samples. The analytes, volatile and basic, were released from sample matrix into the headspace first, and then protonated and dissolved in an aqueous H{sub 3}PO{sub 4} drop hanging in the headspace by a HPLC syringe. After extraction, this drop was directly injected into HPLC. Parameters affecting extraction efficiency were investigated and optimized. This method showed good linearity in the investigated concentration range of 1.0-1500 {mu}g L{sup -1}, repeatability of the extraction (R.S.D. < 5%, n = 6), and low detection limits (0.3 {mu}g L{sup -1} for both analytes). Enrichment factors of about 400-fold and 220-fold were achieved for MAP and AP, respectively, at optimum conditions. The feasibility of the method was demonstrated by analyzing human urine samples.

  16. Quantitative analysis of perfumes in talcum powder by using headspace sorptive extraction.

    Science.gov (United States)

    Ng, Khim Hui; Heng, Audrey; Osborne, Murray

    2012-03-01

    Quantitative analysis of perfume dosage in talcum powder has been a challenge due to interference of the matrix and has so far not been widely reported. In this study, headspace sorptive extraction (HSSE) was validated as a solventless sample preparation method for the extraction and enrichment of perfume raw materials from talcum powder. Sample enrichment is performed on a thick film of poly(dimethylsiloxane) (PDMS) coated onto a magnetic stir bar incorporated in a glass jacket. Sampling is done by placing the PDMS stir bar in the headspace vial by using a holder. The stir bar is then thermally desorbed online with capillary gas chromatography-mass spectrometry. The HSSE method is based on the same principles as headspace solid-phase microextraction (HS-SPME). Nevertheless, a relatively larger amount of extracting phase is coated on the stir bar as compared to SPME. Sample amount and extraction time were optimized in this study. The method has shown good repeatability (with relative standard deviation no higher than 12.5%) and excellent linearity with correlation coefficients above 0.99 for all analytes. The method was also successfully applied in the quantitative analysis of talcum powder spiked with perfume at different dosages. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Effects of alpha-tocopherol on lactones in beef headspace during storage.

    Science.gov (United States)

    Watanabe, A; Imanari, M; Higuchi, M; Shiba, N; Yonai, M

    2010-01-01

    We studied the effect of alpha-tocopherol (alpha-Toc) on the production of lactones, a desirable flavor in Wagyu beef (Japanese Black Cattle), in meat headspace. Fresh beef was minced and divided into 4 groups containing different alpha-Toc levels (1.9, 2.7, 6.1, and 10.7 mg/kg) or packed with oxygen absorber. After 10 d of storage at 2 °C, these samples were cooked in distilled water and rendered fat was collected. The headspace of the fat was analyzed with solid-phase microextraction combined with gas chromatography-mass spectrometry. The DB-17MS capillary column led to good separation of aliphatic lactones. Oxygen was important for the development of all lactones during storage. The amounts of gamma-octalactone and gamma-nonalactone decreased linearly with increasing alpha-Toc levels. The effect of alpha-Toc on delta-decalactone, delta-undecalactone, and delta-tetoradecalactone was weaker, and that on delta-hexadecalactone was ambiguous. These observations suggest that oxidation was necessary to develop the flavor of Wagyu beef, and warn that an excessive increase of alpha-Toc could reduce levels of positive flavor components, gamma-octalactone and gamma-nonalactone, in the headspace of Wagyu beef. © 2010 Institute of Food Technologists®

  18. Development of a syringe pump assisted dynamic headspace sampling technique for needle trap device.

    Science.gov (United States)

    Eom, In-Yong; Niri, Vadoud H; Pawliszyn, Janusz

    2008-07-04

    This paper describes a new approach that combines needle trap devices (NTDs) with a dynamic headspace sampling technique (purge and trap) using a bidirectional syringe pump. The needle trap device is a 22-G stainless steel needle 3.5-in. long packed with divinylbenzene sorbent particles. The same sized needle, without packing, was used for purging purposes. We chose an aqueous mixture of benzene, toluene, ethylbenzene, and p-xylene (BTEX) and developed a sequential purge and trap (SPNT) method, in which sampling (trapping) and purging cycles were performed sequentially by the use of syringe pump with different distribution channels. In this technique, a certain volume (1 mL) of headspace was sequentially sampled using the needle trap; afterwards, the same volume of air was purged into the solution at a high flow rate. The proposed technique showed an effective extraction compared to the continuous purge and trap technique, with a minimal dilution effect. Method evaluation was also performed by obtaining the calibration graphs for aqueous BTEX solutions in the concentration range of 1-250 ng/mL. The developed technique was compared to the headspace solid-phase microextraction method for the analysis of aqueous BTEX samples. Detection limits as low as 1 ng/mL were obtained for BTEX by NTD-SPNT.

  19. Profile of volatile compounds in 11 brandies by headspace solid-phase microextraction followed by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Zhao, Y; Xu, Y; Li, J; Fan, W; Jiang, W

    2009-03-01

    A headspace solid-phase microextraction (HS-SPME) method coupled with gas chromatography-mass spectrometry (GC-MS) was applied for the qualitative or semiquantitative characterization of brandy volatiles. SPME variables (SPME fiber, extraction temperature and time, and ethanol concentration) were optimized. A total of 144 compounds were from the brandies' volatiles, tentatively identified or identified by comparing mass spectra and retention indices of the standards or from literature. Of these, 57 are common to 11 brandies. They were mainly represented by esters and alcohols, such as 2-methyl propanol, 3-methyl butanol, 1-hexanol, ethyl octanoate, and ethyl decanoate, which were quantitatively determined. Chromatographic peaks were integrated using selective ion method (SIM) and the semiquantitative data analyzed using principal component analysis (PCA) and cluster analysis (CA) to study relationships between volatile composition and brandy. Eleven brandies were differentiated into 3 groups: 1 for Hennessy VSOP and XO samples, 1 for Changyu PEGASE VSOP and XO-1, 2, 3 samples, and the other for Changyu PEGASE brandy and VO, Taro brandy, Baiyang River brandy, and Wealth XO samples. The classification of groups is consistent with the brandy samples by variety and grade.

  20. The NINJA-2 project: Detecting and characterizing gravitational waveforms modelled using numerical binary black hole simulations

    CERN Document Server

    :,; Abbott, B P; Abbott, R; Abbott, T; Abernathy, M R; Accadia, T; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ain, A; Ajith, P; Alemic, A; Allen, B; Allocca, A; Amariutei, D; Andersen, M; Anderson, R; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barbet, M; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Bauchrowitz, J; Bauer, Th S; Behnke, B; Bejger, M; Beker, M G; Belczynski, C; Bell, A S; Bell, C; Bergmann, G; Bersanetti, D; Bertolini, A; Betzwieser, J; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biscans, S; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bloemen, S; Blom, M; Bock, O; Bodiya, T P; Boer, M; Bogaert, G; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, Sukanta; Bosi, L; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Buchman, S; Bulik, T; Bulten, H J; Buonanno, A; Burman, R; Buskulic, D; Buy, C; Cadonati, L; Cagnoli, G; Bustillo, J Calderón; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Celerier, C; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chamberlin, S J; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P -F; Colla, A; Collette, C; Colombini, M; Cominsky, L; Constancio, M; Conte, A; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corpuz, A; Corsi, A; Costa, C A; Coughlin, M W; Coughlin, S; Coulon, J -P; Countryman, S; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dahl, K; Canton, T Dal; Damjanic, M; Danilishin, S L; D'Antonio, S; Danzmann, K; Dattilo, V; Daveloza, H; Davier, M; Davies, G S; Daw, E J; Day, R; Dayanga, T; Debreczeni, G; Degallaix, J; Deléglise, S; Del Pozzo, W; Denker, T; Dent, T; Dereli, H; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Dhurandhar, S; Díaz, M; Di Fiore, L; Di Lieto, A; Di Palma, I; Di Virgilio, A; Donath, A; Donovan, F; Dooley, K L; Doravari, S; Dossa, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Dwyer, S; Eberle, T; Edo, T; Edwards, M; Effler, A; Eggenstein, H; Ehrens, P; Eichholz, J; Eikenberry, S S; Endrőczi, G; Essick, R; Etzel, T; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fehrmann, H; Fejer, M M; Feldbaum, D; Feroz, F; Ferrante, I; Ferrini, F; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R P; Flaminio, R; Fournier, J -D; Franco, S; Frasca, S; Frasconi, F; Frede, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gair, J; Gammaitoni, L; Gaonkar, S; Garufi, F; Gehrels, N; Gemme, G; Genin, E; Gennai, A; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, C; Gleason, J; Goetz, E; Goetz, R; Gondan, L; González, G; Gordon, N; Gorodetsky, M L; Gossan, S; Goßler, S; Gouaty, R; Gräf, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Groot, P; Grote, H; Grover, K; Grunewald, S; Guidi, G M; Guido, C; Gushwa, K; Gustafson, E K; Gustafson, R; Hammer, D; Hammond, G; Hanke, M; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hart, M; Hartman, M T; Haster, C -J; Haughian, K; Heidmann, A; Heintze, M; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Heptonstall, A W; Heurs, M; Hewitson, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Hooper, S; Hopkins, P; Hosken, D J; Hough, J; Howell, E J; Hu, Y; Hughey, B; Husa, S; Huttner, S H; Huynh, M; Huynh-Dinh, T; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Iyer, B R; Izumi, K; Jacobson, M; James, E; Jang, H; Jaranowski, P; Ji, Y; Jiménez-Forteza, F; Johnson, W W; Jones, D I; Jones, R; Jonker, R J G; Ju, L; K, Haris; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Karlen, J; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, H; Kawabe, K; Kawazoe, F; Kéfélian, F; Keiser, G M; Keitel, D; Kelley, D B; Kells, W; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, C; Kim, K; Kim, N; Kim, N G; Kim, Y -M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kline, J; Koehlenbeck, S; Kokeyama, K; Kondrashov, V; Koranda, S; Korth, W Z; Kowalska, I; Kozak, D B; Kremin, A; Kringel, V; Krishnan, B; Królak, A; Kuehn, G; Kumar, A; Kumar, P; Kumar, R; Kuo, L; Kutynia, A; Kwee, P; Landry, M; Lantz, B; Larson, S; Lasky, P D; Lawrie, C; Lazzarini, A; Lazzaro, C; Leaci, P; Leavey, S; Lebigot, E O; Lee, C -H; Lee, H K; Lee, H M; Lee, J; Leonardi, M; Leong, J R; Roux, A Le; Leroy, N; Letendre, N; Levin, Y; Levine, B; Lewis, J; Li, T G F; Libbrecht, K; Libson, A; Lin, A C; Littenberg, T B; Litvine, V; Lockerbie, N A; Lockett, V; Lodhia, D; Loew, K; Logue, J; Lombardi, A L; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lough, J; Lubinski, M J; Lück, H; Luijten, E; Lundgren, A P; Lynch, R; Ma, Y; Macarthur, J; Macdonald, E P; MacDonald, T; Machenschalk, B; MacInnis, M; Macleod, D M; Magana-Sandoval, F; Mageswaran, M; Maglione, C; Mailand, K; Majorana, E; Maksimovic, I; Malvezzi, V; Man, N; Manca, G M; Mandel, I; Mandic, V; Mangano, V; Mangini, N; Mantovani, M; Marchesoni, F; Marion, F; Márka, S; Márka, Z; Markosyan, A; Maros, E; Marque, J; Martelli, F; Martin, I W; Martin, R M; Martinelli, L; Martynov, D; Marx, J N; Mason, K; Masserot, A; Massinger, T J; Matichard, F; Matone, L; Matzner, R A; Mavalvala, N; Mazumder, N; Mazzolo, G; McCarthy, R; McClelland, D E; McGuire, S C; McIntyre, G; McIver, J; McLin, K; Meacher, D; Meadors, G D; Mehmet, M; Meidam, J; Meinders, M; Melatos, A; Mendell, G; Mercer, R A; Meshkov, S; Messenger, C; Meyers, P; Miao, H; Michel, C; Mikhailov, E E; Milano, L; Milde, S; Miller, J; Minenkov, Y; Mingarelli, C M F; Mishra, C; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Moe, B; Moesta, P; Mohan, M; Mohapatra, S R P; Moraru, D; Moreno, G; Morgado, N; Morriss, S R; Mossavi, K; Mours, B; Mow-Lowry, C M; Mueller, C L; Mueller, G; Mukherjee, S; Mullavey, A; Munch, J; Murphy, D; Murray, P G; Mytidis, A; Nagy, M F; Kumar, D Nanda; Nardecchia, I; Naticchioni, L; Nayak, R K; Necula, V; Nelemans, G; Neri, I; Neri, M; Newton, G; Nguyen, T; Nitz, A; Nocera, F; Nolting, D; Normandin, M E N; Nuttall, L K; Ochsner, E; O'Dell, J; Oelker, E; Oh, J J; Oh, S H; Ohme, F; Oppermann, P; O'Reilly, B; O'Shaughnessy, R; Osthelder, C; Ottaway, D J; Ottens, R S; Overmier, H; Owen, B J; Padilla, C; Pai, A; Palashov, O; Palomba, C; Pan, H; Pan, Y; Pankow, C; Paoletti, F; Paoletti, R; Papa, M A; Paris, H; Pasqualetti, A; Passaquieti, R; Passuello, D; Pedraza, M; Penn, S; Perreca, A; Phelps, M; Pichot, M; Pickenpack, M; Piergiovanni, F; Pierro, V; Pinard, L; Pinto, I M; Pitkin, M; Poeld, J; Poggiani, R; Poteomkin, A; Powell, J; Prasad, J; Premachandra, S; Prestegard, T; Price, L R; Prijatelj, M; Privitera, S; Prodi, G A; Prokhorov, L; Puncken, O; Punturo, M; Puppo, P; Qin, J; Quetschke, V; Quintero, E; Quiroga, G; Quitzow-James, R; Raab, F J; Rabeling, D S; Rácz, I; Radkins, H; Raffai, P; Raja, S; Rajalakshmi, G; Rakhmanov, M; Ramet, C; Ramirez, K; Rapagnani, P; Raymond, V; Re, V; Read, J; Reed, C M; Regimbau, T; Reid, S; Reitze, D H; Rhoades, E; Ricci, F; Riles, K; Robertson, N A; Robinet, F; Rocchi, A; Rodruck, M; Rolland, L; Rollins, J G; Romano, R; Romanov, G; Romie, J H; Rosińska, D; Rowan, S; Rüdiger, A; Ruggi, P; Ryan, K; Salemi, F; Sammut, L; Sandberg, V; Sanders, J R; Sannibale, V; Santiago-Prieto, I; Saracco, E; Sassolas, B; Sathyaprakash, B S; Saulson, P R; Savage, R; Scheuer, J; Schilling, R; Schnabel, R; Schofield, R M S; Schreiber, E; Schuette, D; Schutz, B F; Scott, J; Scott, S M; Sellers, D; Sengupta, A S; Sentenac, D; Sequino, V; Sergeev, A; Shaddock, D; Shah, S; Shahriar, M S; Shaltev, M; Shapiro, B; Shawhan, P; Shoemaker, D H; Sidery, T L; Siellez, K; Siemens, X; Sigg, D; Simakov, D; Singer, A; Singer, L; Singh, R; Sintes, A M; Slagmolen, B J J; Slutsky, J; Smith, J R; Smith, M; Smith, R J E; Smith-Lefebvre, N D; Son, E J; Sorazu, B; Souradeep, T; Sperandio, L; Staley, A; Stebbins, J; Steinlechner, J; Steinlechner, S; Stephens, B C; Steplewski, S; Stevenson, S; Stone, R; Stops, D; Strain, K A; Straniero, N; Strigin, S; Sturani, R; Stuver, A L; Summerscales, T Z; Susmithan, S; Sutton, P J; Swinkels, B; Tacca, M; Talukder, D; Tanner, D B; Tarabrin, S P; Taylor, R; ter Braack, A P M; Thirugnanasambandam, M P; Thomas, M; Thomas, P; Thorne, K A; Thorne, K S; Thrane, E; Tiwari, V; Tokmakov, K V; Tomlinson, C; Toncelli, A; Tonelli, M; Torre, O; Torres, C V; Torrie, C I; Travasso, F; Traylor, G; Tse, M; Ugolini, D; Unnikrishnan, C S; Urban, A L; Urbanek, K; Vahlbruch, H; Vajente, G; Valdes, G; Vallisneri, M; Brand, J F J van den; Broeck, C Van Den; van der Putten, S; van der Sluys, M V; van Heijningen, J; van Veggel, A A; Vass, S; Vasúth, M; Vaulin, R; Vecchio, A; Vedovato, G; Veitch, J; Veitch, P J; Venkateswara, K; Verkindt, D; Verma, S S; Vetrano, F; Viceré, A; Vincent-Finley, R; Vinet, J -Y; Vitale, S; Vo, T; Vocca, H; Vorvick, C; Vousden, W D; Vyachanin, S P; Wade, A; Wade, L; Wade, M; Walker, M; Wallace, L; Wang, M; Wang, X; Ward, R L; Was, M; Weaver, B; Wei, L -W; Weinert, M; Weinstein, A J; Weiss, R; Welborn, T; Wen, L; Wessels, P; West, M; Westphal, T; Wette, K; Whelan, J T; Whitcomb, S E; White, D J; Whiting, B F; Wiesner, K; Wilkinson, C; Williams, K; Williams, L; Williams, R; Williams, T; Williamson, A R; Willis, J L; Willke, B; Wimmer, M; Winkler, W; Wipf, C C; Wiseman, A G; Wittel, H; Woan, G; Worden, J; Yablon, J; Yakushin, I; Yamamoto, H; Yancey, C C; Yang, H; Yang, Z; Yoshida, S; Yvert, M; Zadrożny, A; Zanolin, M; Zendri, J -P; Zhang, Fan; Zhang, L; Zhao, C; Zhu, X J; Zucker, M E; Zuraw, S; Zweizig, J; Boyle, M; Brügmann, B; Buchman, L T; Campanelli, M; Chu, T; Etienne, Z B; Hannam, M; Healy, J; Hinder, I; Kidder, L E; Laguna, P; Liu, Y T; London, L; Lousto, C O; Lovelace, G; MacDonald, I; Marronetti, P; Mösta, P; Müller, D; Mundim, B C; Nakano, H; Paschalidis, V; Pekowsky, L; Pollney, D; Pfeiffer, H P; Ponce, M; Pürrer, M; Reifenberger, G; Reisswig, C; Santamaría, L; Scheel, M A; Shapiro, S L; Shoemaker, D; Sopuerta, C F; Sperhake, U; Szilágyi, B; Taylor, N W; Tichy, W; Tsatsin, P; Zlochower, Y

    2014-01-01

    The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave astrophysics communities. The purpose of NINJA is to study the ability to detect gravitational waves emitted from merging binary black holes and recover their parameters with next-generation gravitational-wave observatories. We report here on the results of the second NINJA project, NINJA-2, which employs 60 complete binary black hole hybrid waveforms consisting of a numerical portion modelling the late inspiral, merger, and ringdown stitched to a post-Newtonian portion modelling the early inspiral. In a "blind injection challenge" similar to that conducted in recent LIGO and Virgo science runs, we added 7 hybrid waveforms to two months of data recolored to predictions of Advanced LIGO and Advanced Virgo sensitivity curves during their first observing runs. The resulting data was analyzed by gravitational-wave detection algorithms and 6 of the waveforms were recovered w...

  1. Characterization of the 80-mm diameter Hamamatsu PMTs for the KM3NeT project

    Energy Technology Data Exchange (ETDEWEB)

    Aiello, S.; Giordano, V.; Leonora, E., E-mail: emanuele.leonora@ct.infn.it [INFN, sezione di Catania, Via S.Sofia 64, 95125, Catania (Italy); Classen, L.; Reubelt, J. [ECAP, Erwin-Rommel-Str. 1, 91052, Erlangen (Germany); Peek, H.; Visser, E. [NIKHEF, Science Park, Amsterdam (Netherlands); Samtleben, D. [NIKHEF, Science Park, Amsterdam, The Netherlands and Leiden University, Leiden Institute of Physics, PO Box 9504, Leiden, 2300 RA (Netherlands); Kalekin, Oleg, E-mail: kalekin@physik.uni-erlangen.de; Collaboration: KM3NeT Collaboration

    2014-11-18

    The optical module designed for the KM3NeT project consists of 31 photomultipliers of 3-inch diameter housed into a 17-inch diameter glass sphere. A proposed photomultiplier was the R12199-02 Hamamatsu 80-mm diameter. 203 of such PMTs have been delivered from Hamamatsu and tested by the KM3NeT groups of NIKHEF-Amsterdam, ECAP-Erlangen and INFN-Catania. Tests have been performed to measure the main parameters, such as gain, transit time spread, dark pulses rate, fraction of spurious pulses, quantum efficiency and effective photocathode size. The main results matched with the requirements of the project. Methods and results are presented in this report.

  2. MISTY ECHO Tunnel Dynamics Experiment--Data report: Volume 1; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, J.S.; Luke, B.A.; Long, J.W.; Lee, J.G.

    1992-04-01

    Tunnel damage resulting from seismic loading is an important issue for the Yucca Mountain nuclear waste repository. The tunnel dynamics experiment was designed to obtain and document ground motions, permanent displacements, observable changes in fracture patterns, and visible damage at ground motion levels of interest to the Yucca Mountain Project. Even though the maximum free-field loading on this tunnel was 28 g, the damage observed was minor. Fielding details, data obtained, and supporting documentation are reported.

  3. The Wudapt Project: Engaging a Global Community to Map and Characterize Cities Worldwide

    Science.gov (United States)

    Feddema, J. J.; Mills, G.; See, L. M.; Bechtel, B.; Ching, J.

    2016-12-01

    Over 50% of the world's population lives is urban areas that occupy about 2-4% of the terrestrial surface. These human built environments account for approximately 70% of anthropogenic carbon emissions and within these locations we observe some of the most extreme human altered climates with direct impacts on human health and air quality. Counterintuitively, while most humans live in urban spaces, there is a dearth of knowledge about the true nature of these urban spaces. Within human settlements there are significant variations in building types, building materials, energy management systems, transport systems, water and air quality management systems and socio-economic activities. For most of the world's cities there are few if any observations of these systems, and little knowledge of urban extent and distribution of urban types within cities. The World Urban Database and Portal Tools (WUDAPT), aims to fill this knowledge gap. This project merges local expert knowledge with open source remote sensing tools, Landsat data and GIS software to classify cities into 10 major neighborhood scale classes based on urban morphology characteristics. Known as Local Climate Zones (LCZs), these classes represent relatively homogeneous urban areas that can give a first approximation to typical urban climate and environmental impacts regardless of location or temporal occurrence. This project is designed to engage scientists and citizens in the mapping process, but also to provide participants (citizens, scientists, planners and policy makers) with output products. To date this project has classified about 200 cities worldwide. This presentation illustrates the process and products of the WUDAPT project and its potential benefits for local and global science. A next step will develop methods for linking LCZ areas to socioeconomic information and local building characteristics and uses.

  4. The Dust Management Project: Characterizing Lunar Environments and Dust, Developing Regolith Mitigation Technology and Simulants

    Science.gov (United States)

    Hyatt, Mark J.; Straka, Sharon A.

    2010-01-01

    A return to the Moon to extend human presence, pursue scientific activities, use the Moon to prepare for future human missions to Mars, and expand Earth?s economic sphere, will require investment in developing new technologies and capabilities to achieve affordable and sustainable human exploration. From the operational experience gained and lessons learned during the Apollo missions, conducting long-term operations in the lunar environment will be a particular challenge, given the difficulties presented by the unique physical properties and other characteristics of lunar regolith, including dust. The Apollo missions and other lunar explorations have identified significant lunar dust-related problems that will challenge future mission success. Comprised of regolith particles ranging in size from tens of nanometers to microns, lunar dust is a manifestation of the complex interaction of the lunar soil with multiple mechanical, electrical, and gravitational effects. The environmental and anthropogenic factors effecting the perturbation, transport, and deposition of lunar dust must be studied in order to mitigate it?s potentially harmful effects on exploration systems and human explorers. The Dust Management Project (DMP) is tasked with the evaluation of lunar dust effects, assessment of the resulting risks, and development of mitigation and management strategies and technologies related to Exploration Systems architectures. To this end, the DMP supports the overall goal of the Exploration Technology Development Program (ETDP) of addressing the relevant high priority technology needs of multiple elements within the Constellation Program (CxP) and sister ETDP projects. Project scope, plans, and accomplishments will be presented.

  5. Analytical results for the 107-N and 1310-N basin sedimentdisposition sample characterization project

    Energy Technology Data Exchange (ETDEWEB)

    Miller, G.L.

    1997-06-02

    Turnaround time for this project was 60 days, as required in Reference 2. The analyses were to be performed using SW-846 procedures whenever possible to meet analytical requirements as a Resource Conservation Recovery Act (RCRA) protocol project. Except for the preparation and analyses of polychlorinated biphenyl hydrocarbons (PCB) and Nickel-63, which the program deleted as a required analyte for 222-S Laboratory, all preparative and analytical work was performed at the 222-S Laboratory. Quanterra Environmental Services of Earth City, Missouri, performed the PCB analyses. During work on this project, two events occurred nearly simultaneously, which negatively impacted the 60 day deliverable schedule: an analytical hold due to waste handling issues at the 222-S Laboratory, and the discovery of PCBs at concentrations of regulatory significance in the 105-N Basin samples. Due to findings of regulatory non-compliance by the Washington State, Department of Ecology, the 222-S Laboratory placed a temporary administrative hold on its analytical work until all waste handling, designation and segregation issues were resolved. During the hold of approximately three weeks, all analytical and waste.handling procedures were rewritten to comply with the legal regulations, and all staff were retrained in the designation, segregation and disposal of RCRA liquid and solid wastes.

  6. DEVELOPMENT OF A SYSTEMATIC ANALYSIS FOR THE CHARACTERIZATION OF SPANISH PRODUCTIVE SME PERFORMING PROJECTS R&D&I

    Directory of Open Access Journals (Sweden)

    PEREZ MOLINA Ana Isabel

    2014-05-01

    Full Text Available Innovation in SMEs is a key to competitiveness and economic growth pillar. Currently, in Spain, the most important policy to support innovation is tax incentives for R&D&I, based on the issuance of Motivated Binding reports of the Ministry of Economy and Competitiveness. This work offers SMEs a quantitative and qualitative model of analysis, and enterprise-level projects, which aims to help them get a favorable structure for innovation. Specifically, a systematic analysis is proposed for Spanish SMEs that perform productive R&D&I, based on factors of company, projects and on both of them, and based on an interview for SMEs, on an analysis of the projects based Motivated Binding a Report and on a review of key data presented in the Mercantile Register. The method developed has been endorsed by a panel of experts in the field: managers related to innovation, researchers from the University, Agents involved in Institutions binding Motivated management Reports, Managers of innovative SMEs, Business Associations, etc. By providing a systematic analysis, it will be able to make a quantitative and qualitative empirical study of a representative sample of companies, based on the application of this method. With all this, we will achieve the characterization and modeling of the Spanish productive SMEs performing R&D&I, obtaining, a model able to assist Spanish companies to achieve including the R&D&I, in its business strategy, which will generate new possibilities for improving competitiveness.

  7. Complementary primary mental health programs for young people in Australia: Access to Allied Psychological Services (ATAPS) and headspace.

    Science.gov (United States)

    Bassilios, Bridget; Telford, Nicolas; Rickwood, Debra; Spittal, Matthew J; Pirkis, Jane

    2017-01-01

    Access to Allied Psychological Services (ATAPS) was introduced in 2001 by the Australian Government to provide evidence-based psychological interventions for people with high prevalence disorders. headspace, Australia's National Youth Mental Health Foundation, was established in 2006 to promote and facilitate improvements in the mental health, social wellbeing and economic participation of young people aged 12-25 years. Both programs provided free or low cost psychological services. This paper aims to describe the uptake of psychological services by people aged 12-25 years via ATAPS and headspace, the characteristics of these clients, the types of services received and preliminary client outcomes achieved. Data from 1 July 2009 to 30 June 2012 were sourced from the respective national web-based minimum datasets used for routine data collection in ATAPS and headspace. In total, 20,156 and 17,337 young people accessed two or more psychological services via ATAPS and headspace, respectively, in the 3-year analysis period. There were notable differences between the clients of, and the services delivered by, the programs. ATAPS clients were less likely to be male (31 vs 39%) and to reside in major cities (51 vs 62%) than headspace clients; ATAPS clients were also older (18-21 vs 15-17 years modal age group). There was some variation in the number and types of psychological sessions that young people received via the programs but the majority received at least one session of cognitive behavioural therapy. Based on limited available outcome data, both programs appear to have produced improvements in clients' mental health; specifically, psychological distress as assessed by the Kessler-10 (K-10) was reduced. ATAPS and headspace have delivered free or low-cost psychological services to 12-25 year olds with somewhat different characteristics. Both programs have had promising effects on mental health. ATAPS and headspace have operated in a complementary fashion to fill a

  8. DQO Summary Report for 324 and 327 Building Hot Cells D4 Project Waste Characterization

    Energy Technology Data Exchange (ETDEWEB)

    T.A. Lee

    2006-02-06

    This data quality objective (DQO) summary report provides the results of the DQO process conducted for waste characterization activities for the 324 and 327 Building hot cells decommission, deactivate, decontaminate, and demolish activities. This DQO summary report addresses the systems and processes related to the hot cells, air locks, vaults, tanks, piping, basins, air plenums, air ducts, filters, an adjacent elements that have high dose rates, high contamination levels, and/or suspect transuranic waste, which will require nonstandard D4 techniques.

  9. Final report on the Background Soil Characterization Project at the Oak Ridge Reservation, Oak Ridge, Tennessee. Volume 1: Results of Field Sampling Program

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, D.R.; Ammons, J.T.; Branson, J.L. [and others

    1993-10-01

    This report presents, evaluates, and documents data and results obtained in the Background Soil Characterization Project (BSCP). It is intended to be a stand-alone document for application and use in structuring and conducting remedial investigation and remedial action projects in the Environmental Restoration (ER) Program. The objectives of the BSCP consist of the following: determine background concentrations of organics, metals, and radionuclides in natural soils that are key to environmental restoration projects; provide remediation projects with 100% validated data on background concentrations, which are technically and legally defensible; and quantify baseline risks from background constituents for comparison of risks associated with contaminated sites.

  10. Morphological characterization of spinal cord dorsal horn lamina I neurons projecting to the parabrachial nucleus in the rat.

    Science.gov (United States)

    Almarestani, L; Waters, S M; Krause, J E; Bennett, G J; Ribeiro-da-Silva, A

    2007-09-20

    Many Rexed's lamina I neurons are nociceptive and project to the brain. Lamina I projection neurons can be classified as multipolar, fusiform, or pyramidal, based on cell body shape and characteristics of their proximal dendrites in the horizontal plane. There is also evidence that both multipolar and fusiform cells are nociceptive and pyramidal neurons nonnociceptive. In this investigation we identified which types of lamina I neurons belong to the spinoparabrachial tract in the rat and characterized them regarding the presence or absence of neurokinin-1 receptor (NK-1r) immunoreactivity. For this, cholera toxin subunit B (CTb), conjugated to a fluorescent marker was injected unilaterally into the parabrachial nucleus. Sections were additionally stained for the detection of NK-1r immunoreactivity and were examined using fluorescence and confocal microscopy. Serial confocal optical sections and 3D reconstructions were obtained for a considerable number of neurons per animal. Using immunofluorescence, we assessed the proportion of lamina I neurons belonging to the spinoparabrachial (SPB) tract and/or expressing NK-1r. The relative distribution of neurons belonging to the SPB tract was: 38.7% multipolar, 36.8% fusiform, 22.7% pyramidal, and 1.9% unclassified. Most of the SPB neurons expressing NK-1r were either multipolar or fusiform. Pyramidal SPB neurons were seldom immunoreactive for NK-1r, an observation that provides further support to the concept that most lamina I projection neurons of the pyramidal type are nonnociceptive. In addition, our study provides further evidence that these distinct morphological types of neurons differ in their phenotypic properties, but not in their projection patterns.

  11. Initial characterization of the groundwater system near the Lower Colorado Water Supply Project, Imperial Valley, California

    Science.gov (United States)

    Coes, Alissa L.; Land, Michael; Densmore, Jill N.; Landrum, Michael T.; Beisner, Kimberly R.; Kennedy, Jeffrey R.; Macy, Jamie P.; Tillman, Fred D

    2015-01-01

    In 2009, the U.S. Geological Survey, in cooperation with the city of Needles, began a study of the hydrogeology along the All-American Canal, which conveys water from the Colorado River to the Imperial Valley. The focus of this study was to gain a better understanding of the effect of lining the All-American Canal, and other management actions, on future total dissolved solids concentrations in groundwater pumped by Lower Colorado Water Supply Project wells that is delivered to the All-American Canal. The study included the compilation and evaluation of previously published hydrogeologic and geochemical information, establishment of a groundwater-elevation and groundwater-quality monitoring network, results of monitoring groundwater elevations and groundwater quality from 2009 to 2011, site-specific hydrologic investigations of the Lower Colorado Water Supply Project area, examination of groundwater salinity by depth by using time-domain electromagnetic surveys, and monitoring of groundwater-storage change by using microgravity methods. 

  12. Evaluation of the effects of underground water usage and spillage in the Exploratory Studies Facility; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, E.; Sobolik, S.R.

    1993-12-01

    The Yucca Mountain Site Characterization Project is studying Yucca Mountain in southwestern Nevada as a potential site for a high-level radioactive waste repository. Analyses reported herein were performed to support the design of site characterization activities so that these activities will have a minimal impact on the ability of the site to isolate waste and a minimal impact on underground tests performed as part of the characterization process. These analyses examine the effect of water to be used in the underground construction and testing activities for the Exploratory Studies Facility on in situ conditions. Underground activities and events where water will be used include construction, expected but unplanned spills, and fire protection. The models used predict that, if the current requirements in the Exploratory Studies Facility Design Requirements are observed, water that is imbibed into the tunnel wall rock in the Topopah Springs welded tuff can be removed over the preclosure time period by routine or corrective ventilation, and also that water imbibed into the Paintbrush Tuff nonwelded tuff will not reach the potential waste storage area.

  13. Coastal Fog in Atlantic Canada: Characterization and Projection in a Changing Climate

    Science.gov (United States)

    Duplessis, P.; Hartery, S.; Macdonald, A. M.; Wheeler, M.; Miller, J.; Bhatia, S.; Chang, R. Y. W.

    2016-12-01

    Marine and coastal fog in Atlantic Canada is usually advective and favored by the meeting of the warm Gulf Stream and cold Labrador Current. As moist warm air moves over cold water, it cools down and becomes supersaturated. The interactions between microphysical, dynamical and radiative processes can also be a determining element in the formation and persistence of fog, which makes fog forecasting a highly challenging task. Current parameterizations within models suffer notably from unresolved microphysical problems such as neglecting droplet concentration, which leads to errors in droplet density predictions of up to 50%. In the scope of improving our understanding of fog and its characteristics, our research group conducted a field study on the coast of Nova Scotia in Eastern Canada during the fog season of 2016. Meteorological variables, droplet and aerosol size distributions, chemical speciation and fog water composition were measured. Results from this study will be presented, along with projections in a changing climate.

  14. Experimental and Numerical Characterization of Synthetic and Natural Rock Properties in Support of the NEESROCK Project

    Science.gov (United States)

    Adams, S.; Smith, S.; Maclaughlin, M.; Wartman, J.; Applegate, K. N.; Gibson, M. D.; Arnold, L.; Keefer, D. K.

    2013-12-01

    Seismically induced rock slope failures are one of the most dangerous and least understood of all seismic hazards. The NEESROCK project, a collaboration between researchers at the University of Washington, Montana Tech, and the University of Maine, is supported by the National Science Foundation through its Network for Earthquake Engineering Simulation (NEES) program. The overall goal of the project is to advance our understanding of the fundamental mechanisms of the rock-slope failure process by integrating centrifuge physical modeling and distinct element numerical simulations in order to develop more advanced predictive tools and analysis procedures. Centrifuge experiments will calibrate and verify the numerical models. A fundamental component of this project and the primary focus of the Montana Tech research is laboratory testing of the synthetic materials used in the centrifuge models and comparison of these materials with natural rock specimens. Properties such as strength of the intact material, the geometry and strength of material interfaces, and the material's response to deformation and wave propagation are being studied with laboratory experiments that include tilt table tests, direct shear tests, laser scanning of the interface surfaces, unconfined compression tests, ultrasonic velocity tests, and free-free resonant column tests. The numerical modeling portion of the study is being used to simulate selected laboratory tests to investigate the abilities of the distinct element programs (Itasca's Universal Distinct Element Code (UDEC) and Particle Flow Code (PFC) software) to simulate the material behavior in the laboratory. Direct shear test results, in particular, are used to validate the performance of the joint constitutive models in UDEC. The experimental ultrasonic velocity tests, in combination with unconfined compression tests, are being used to investigate the relationship between static and dynamic modulus values for the project material as

  15. West Hackberry Brine Disposal Project pre-discharge characterization. Final report

    Energy Technology Data Exchange (ETDEWEB)

    DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C. (eds.)

    1982-01-01

    The physical, chemical and biological attributes are described for: (1) a coastal marine environment centered about a Department of Energy Strategic Petroleum Reserve (SPR) brine disposal site 11.4 km off the southwest coast of Louisiana; and (2) the lower Calcasieu and Sabine estuarine systems that provide leach waters for the SPR project. A three month sampling effort, February through April 1981, and previous investigations from the study area are integrated to establish baseline information for evaluation of impacts from brine disposal in the nearshore marine waters and from freshwater withdrawal from the coastal marsh of the Chenier Plain. January data are included for some tasks that sampled while testing and mobilizing their instruments prior to the February field effort. The study addresses the areas of physical oceanography, estuarine hydrology and hydrography, water and sediment quality, benthos, nekton, phytoplankton, zooplankton, and data management.

  16. Characterization of the Metabochip in diverse populations from the International HapMap Project in the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) project.

    Science.gov (United States)

    Crawford, Dana C; Goodloe, Robert; Brown-Gentry, Kristin; Wilson, Sarah; Roberson, Jamie; Gillani, Niloufar B; Ritchie, Marylyn D; Dilks, Holli H; Bush, William S

    2013-01-01

    Genome-wide association studies (GWAS) have identified hundreds of genomic regions associated with common human disease and quantitative traits. A major research avenue for mature genotype-phenotype associations is the identification of the true risk or functional variant for downstream molecular studies or personalized medicine applications. As part of the Population Architecture using Genomics and Epidemiology (PAGE) study, we as Epidemiologic Architecture for Genes Linked to Environment (EAGLE) are fine-mapping GWAS-identified genomic regions for common diseases and quantitative traits. We are currently genotyping the Metabochip, a custom content BeadChip designed for fine-mapping metabolic diseases and traits, in∼15,000 DNA samples from patients of African, Hispanic, and Asian ancestry linked to de-identified electronic medical records from the Vanderbilt University biorepository (BioVU). As an initial study of quality control, we report here the genotyping data for 360 samples of European, African, Asian, and Mexican descent from the International HapMap Project. In addition to quality control metrics, we report the overall allele frequency distribution, overall population differentiation (as measured by FST), and linkage disequilibrium patterns for a select GWAS-identified region associated with low-density lipoprotein cholesterol levels to illustrate the utility of the Metabochip for fine-mapping studies in the diverse populations expected in EAGLE, the PAGE study, and other efforts underway designed to characterize the complex genetic architecture underlying common human disease and quantitative traits.

  17. Flares of Nearby, Mid-to-late M-dwarfs Characterized by the MEarth Project

    Science.gov (United States)

    Mondrik, Nicholas; Charbonneau, David; Irwin, Jonathan; Newton, Elisabeth R.

    2017-01-01

    Stellar flares are both a curse and a blessing: Transit and radial velocity searches for exoplanets are hindered by the variability caused by flares, while the characteristics of this variability offer valuable insight into the magnetic properties of the star. We present an analysis of flare events of nearby, mid-to-late M-dwarfs from the MEarth Project. MEarth consists of a northern and a southern array of 8 telescopes each that photometrically monitors most mid-to-late M-dwarfs within 30 parsecs. Although the initial motivation was to search for exoplanet transits, the cadence of approximately 20 minutes is well-suited to capturing long-lived flares. However, MEarth employs a single, wide, red bandpass, which poses challenges to the robust detection of flare events, which are typically bluer in color. Using MEarth data, our team has recently published trigonometric parallaxes and estimates of rotation periods for an unprecedented number of nearby low-mass stars. We also gathered supplementary optical and near infrared spectra of a subset of these stars. We describe here the properties of the flares detected by MEarth, and explore the relation of the presence of flares on individual stars with stellar parameters such as rotational period, mass, and H-alpha equivalent width. We also provide an estimate of flare rate for individual stars by injecting flares into our pipeline.The MEarth project acknowledges funding from the National Science Foundation and the David and Lucile Packard Foundation Fellowship for Science and Engineering. This work was made possible through the support of a grant from the John Templeton Foundation.

  18. The AlpArray-CASE project: temporary broadband seismic network deployment and characterization

    Science.gov (United States)

    Dasović, Iva; Molinari, Irene; Stipčević, Josip; Šipka, Vesna; Salimbeni, Simone; Jarić, Dejan; Prevolnik, Snježan; Kissling, Eduard; Clinton, John; Giardini, Domenico

    2017-04-01

    While the northern part of the Adriatic microplate will be accurately imaged within the AlpArray project, its central and southern parts deserve detailed studies to obtain a complete picture of its structure and evolution. The Adriatic microplate forms the upper plate in the Western and Central Alps whereas it forms the lower plate in the Apennines and the Dinarides. However, the tectonics of Adriatic microplate is not well constrained and remains controversial, especially with regard to its contact with the Dinarides. The primary goal of the Central Adriatic Seismic Experiment (CASE) is to provide high quality seismological data and to shed light on seismicity and 3D lithospheric structure of the central Adriatic microplate and its boundaries. The CASE project is an international AlpArray Complementary Experiment carried out by four institutions: Department of Earth Sciences and Swiss Seismological Service of ETH Zürich (CH), Department of Geophysics and Croatian Seismological Service of Faculty of Science at University of Zagreb (HR), Republic Hydrometeorological Service of Republic of Srpska (BIH) and Istituto Nazionale di Geofisica e Vulcanologia (I). It establishes a temporary seismic network, expected to be operational at least for one year, composed by existing permanent and temporary seismic stations operated by the institutions involved and newly deployed temporary seismic stations, installed in November and December 2016, provided by ETH Zürich and INGV: five in Croatia, four in Bosnia and Herzegovina and two in Italy. In this work, we present stations sites and settings and discuss their characteristics in terms of site-effects and noise level of each station. In particular, we analyse the power spectral density estimates in order to investigate major sources of noise and background noise.

  19. The NYC native air sampling pilot project: using HVAC filter data for urban biological incident characterization.

    Science.gov (United States)

    Ackelsberg, Joel; Leykam, Frederic M; Hazi, Yair; Madsen, Larry C; West, Todd H; Faltesek, Anthony; Henderson, Gavin D; Henderson, Christopher L; Leighton, Terrance

    2011-09-01

    Native air sampling (NAS) is distinguished from dedicated air sampling (DAS) devices (eg, BioWatch) that are deployed to detect aerosol disseminations of biological threat agents. NAS uses filter samples from heating, ventilation, and air conditioning (HVAC) systems in commercial properties for environmental sampling after DAS detection of biological threat agent incidents. It represents an untapped, scientifically sound, efficient, widely distributed, and comparably inexpensive resource for postevent environmental sampling. Calculations predict that postevent NAS would be more efficient than environmental surface sampling by orders of magnitude. HVAC filter samples could be collected from pre-identified surrounding NAS facilities to corroborate the DAS alarm and delineate the path taken by the bioaerosol plume. The New York City (NYC) Native Air Sampling Pilot Project explored whether native air sampling would be acceptable to private sector stakeholders and could be implemented successfully in NYC. Building trade associations facilitated outreach to and discussions with property owners and managers, who expedited contact with building managers of candidate NAS properties that they managed or owned. Nominal NAS building requirements were determined; procedures to identify and evaluate candidate NAS facilities were developed; data collection tools and other resources were designed and used to expedite candidate NAS building selection and evaluation in Manhattan; and exemplar environmental sampling playbooks for emergency responders were completed. In this sample, modern buildings with single or few corporate tenants were the best NAS candidate facilities. The Pilot Project successfully demonstrated that in one urban setting a native air sampling strategy could be implemented with effective public-private collaboration.

  20. Comparative studies of the static and dynamic headspace extraction of saturated short chain aldehydes from cellulose-based packaging materials.

    Science.gov (United States)

    Wenzl, T; Lankmayr, E P

    2002-03-01

    Aldehydes in cellulose-based materials such as cardboard are derived from lipid degradation. Depending on the production- and storage conditions of the cardboard, the aldehyde content changes. Owing to their sensorial properties, accurate control of their content is obligatory. The cardboard usually exhibits strong and even varying matrix effects and considerable inhomogeneity. The comparability of results of analysis after static and dynamic headspace extraction of short chained saturated aldehydes from cellulose-based matrices was studied. In the case of the static extraction technique, special attention was given to the establishment of the headspace equilibrium, which could be reached by the addition of water as a displacer. For dynamic headspace extraction, the volatiles were purged from the matrix by an inert gas and enriched on an adsorbent trap. In theory, the extraction yield should be 100%. Since there are no certified reference materials for verification of the extraction efficiency available, confirmation was achieved by determining the total amount of analytes in the sample by means of multiple headspace extraction.In comparison to the static operation mode, the major drawbacks of the dynamic technique were found to be based on a more complex parameter string and on limitations to the extractable sample quantities, which may result in enhanced uncertainty of the measurements. Nevertheless, the results of analysis pointed out that both headspace extraction techniques are suitable for the determination of volatile aldehydes from cellulose-based materials.

  1. Quantitative Analysis of Bioactive Compounds from Aromatic Plants by Means of Dynamic Headspace Extraction and Multiple Headspace Extraction-Gas Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Omar, Jone; Olivares, Maitane; Alonso, Ibone; Vallejo, Asier; Aizpurua-Olaizola, Oier; Etxebarria, Nestor

    2016-04-01

    Seven monoterpenes in 4 aromatic plants (sage, cardamom, lavender, and rosemary) were quantified in liquid extracts and directly in solid samples by means of dynamic headspace-gas chromatography-mass spectrometry (DHS-GC-MS) and multiple headspace extraction-gas chromatography-mass spectrometry (MHSE), respectively. The monoterpenes were 1st extracted by means of supercritical fluid extraction (SFE) and analyzed by an optimized DHS-GC-MS. The optimization of the dynamic extraction step and the desorption/cryo-focusing step were tackled independently by experimental design assays. The best working conditions were set at 30 °C for the incubation temperature, 5 min of incubation time, and 40 mL of purge volume for the dynamic extraction step of these bioactive molecules. The conditions of the desorption/cryo-trapping step from the Tenax TA trap were set at follows: the temperature was increased from 30 to 300 °C at 150 °C/min, although the cryo-trapping was maintained at -70 °C. In order to estimate the efficiency of the SFE process, the analysis of monoterpenes in the 4 aromatic plants was directly carried out by means of MHSE because it did not require any sample preparation. Good linearity (r2) > 0.99) and reproducibility (relative standard deviation % <12) was obtained for solid and liquid quantification approaches, in the ranges of 0.5 to 200 ng and 10 to 500 ng/mL, respectively. The developed methods were applied to analyze the concentration of 7 monoterpenes in aromatic plants obtaining concentrations in the range of 2 to 6000 ng/g and 0.25 to 110 μg/mg, respectively.

  2. Effect of destoned olive cake on the aromatic profile of cows’ milk and dairy products: comparison of two techniques for the headspace aroma profile analysis

    Directory of Open Access Journals (Sweden)

    Anna Rocchina Caputo

    2015-03-01

    Full Text Available The aim of this study, carried out within the NOVOROD project (PSR Campania 2007-2013 Misura 124 HC, was to evaluate the aromatic profile of milk and dairy products of dairy cows supplemented with destoned olive cake (DOC. Two techniques for the headspace aroma profile analysis: the thermal desorption by gas chromatography with a mass selective (GC/MS detector and the electronic nose were compared. The trial was performed into a dairy cow farm. Ten dairy cows were allotted into two homogenous groups: control and experimental. Animals received the same diet, while in the experimental group the concentrate supplementation (15% dry matter was replaced with DOC. After two weeks of adaptation, animals were fed with the experimental diet for other 15 days. During the experimental period, the milk was collected and cumulatively processed in Caciotta cheese (a soft cheese, 25 days ripened and in Semicotto cheese (hard cheese, 3 months ripened for 13 times for each group. Milk and cheese volatile organic compounds (VOCs were extracted and concentrated with dynamic headspace method and determined by GC/MS. Statistical analysis of data, expressed in arbitrary units (a.u.=peak area × 10–6 and allotted in compound classes, was carried out by ANOVA. All data collected of VOCs were processed with principal component analysis (PCA. Milk and cheese samples were comparatively analysed with the electronic nose, fitted with a tenmetal oxide sensors electronic device. PCA has been used for the evaluation of the pattern data. Our results show that the use of DOC, as an unconventional feed for livestock, has no effect on the aromatic profile of both milk and dairy products. In fact, no significant differences were found in both milk and dairy products between the two groups using the GC/MS method. Also the discriminating analysis carried out by electronic nose did not show significant differences between the two groups. The two compared techniques seem to lead to

  3. North American landscape characterization project: The production of a continental scale three‐decade Landsat data set

    Science.gov (United States)

    Sohl, Terry L.; Dwyer, John L.

    1998-01-01

    The North American Landscape Characterization (NALC) project is a component of the National Aeronautics and Space Administration (NASA) Landsat Pathfinder program. Pathfinder projects are focused on the investigation of global change utilizing current remote sensing technologies. The NALC project is a cooperative effort between the U. S. Environmental Protection Agency (EPA), the U.S. Geological Survey (USGS), and NASA to make Landsat data available to the widest possible user community for scientific research and general public interest. The NALC project is principally funded by the EPA Office of Research and Development and the USGS's Earth Resources Observation Systems (EROS) Data Center (EDC).The objectives of the NALC project are to produce standardized remote sensing data sets, develop standardized analysis methods, and derive standardized land cover change products for a large portion of the North American continent (the conterminous United States and Mexico) (Lunetta and Sturdevant, 1993). The standard product is the NALC “triplicate”;, consisting of co‐registered Landsat multispectral scanner data for the years 1973, 1986, and 1991 (plus or minus one year), plus co‐registered 3 arcsecond digital terrain elevation data. Processing began with the 1986 scene, which was precision corrected (with full terrain correction) to a 60 meter Universal Transverse Mercator base. Automated cross‐correlation procedures were used to co‐register the 1970's and 1990's data to the 1980's base, and independent verifications of registration quality were performed on all triplicate components. The pertinent metadata were compiled in a relational database, which includes WRS2 path/rows, scene ID's, image dates, solar azimuth and elevation, verification RMSE's, and the number of verification control points. NALC triplicate data sets are being used for a number of applications, including the analysis of urbanization patterns, dynamics of climatic fluctuations

  4. Characterization and heat flux testing of beryllium coatings on Inconel for JET ITER-like wall project

    Energy Technology Data Exchange (ETDEWEB)

    Hirai, T [Forschungszentrum Juelich, Association EURATOM-FZJ, 52425 Juelich (Germany); Linke, J [Forschungszentrum Juelich, Association EURATOM-FZJ, 52425 Juelich (Germany); Sundelin, P [Alfven Laboratory, Association EURATOM-VR, 100 44 Stockholm (Sweden); Rubel, M [Alfven Laboratory, Association EURATOM-VR, 100 44 Stockholm (Sweden); Kuehnlein, W [Forschungszentrum Juelich, Association EURATOM-FZJ, 52425 Juelich (Germany); Wessel, E [Forschungszentrum Juelich, Association EURATOM-FZJ, 52425 Juelich (Germany); Coad, J P [Culham Science Centre, EURATOM-UKAEA Fusion Association, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Lungu, C P [National Institute of Lasers, Plasma and Radiation Physics, Association EURATOM-MEdC, Bucharest (Romania); Matthews, G F [Culham Science Centre, EURATOM-UKAEA Fusion Association, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Pedrick, L [Culham Science Centre, EURATOM-UKAEA Fusion Association, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Piazza, G [EFDA, CSU, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom)

    2007-03-15

    In order to perform a fully integrated material test, JET has launched the ITER-like wall project with the aim of installing a full metal wall during the next major shutdown. The material foreseen for the main chamber wall is bulk Be at the limiters and Be coatings on inconel tiles elsewhere. R and D process comprises global characterization (structure, purity etc) of the evaporated films and testing of their performance under heat loads. The major results are (i) the layers have survived energy loads of 20 MJ m{sup -2} which is significantly above the required level of 5-10 MJ m{sup -2} (ii) melting limit of beryllium coating would be at the energy level of 30 MJ m{sup -2} (iii) cyclic thermal load of 10 MJ m{sup -2} for up to 50 cycles have not induced any noticeable damage such as flaking or detachment.

  5. The NINJA-2 project: detecting and characterizing gravitational waveforms modelled using numerical binary black hole simulations

    Science.gov (United States)

    Aasi, J.; Abbott, B. P.; Abbott, R.; Abbott, T.; Abernathy, M. R.; Accadia, T.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Affeldt, C.; Agathos, M.; Aggarwal, N.; Aguiar, O. D.; Ain, A.; Ajith, P.; Alemic, A.; Allen, B.; Allocca, A.; Amariutei, D.; Andersen, M.; Anderson, R.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C.; Areeda, J.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Austin, L.; Aylott, B. E.; Babak, S.; Baker, P. T.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barbet, M.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Bauchrowitz, J.; Bauer, Th S.; Behnke, B.; Bejger, M.; Beker, M. G.; Belczynski, C.; Bell, A. S.; Bell, C.; Bergmann, G.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biscans, S.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bloemen, S.; Blom, M.; Bock, O.; Bodiya, T. P.; Boer, M.; Bogaert, G.; Bogan, C.; Bond, C.; Bondu, F.; Bonelli, L.; Bonnand, R.; Bork, R.; Born, M.; Boschi, V.; Bose, Sukanta; Bosi, L.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brückner, F.; Buchman, S.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burman, R.; Buskulic, D.; Buy, C.; Cadonati, L.; Cagnoli, G.; Calderón Bustillo, J.; Calloni, E.; Camp, J. B.; Campsie, P.; Cannon, K. C.; Canuel, B.; Cao, J.; Capano, C. D.; Carbognani, F.; Carbone, L.; Caride, S.; Castiglia, A.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Celerier, C.; Cella, G.; Cepeda, C.; Cesarini, E.; Chakraborty, R.; Chalermsongsak, T.; Chamberlin, S. J.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Chen, X.; Chen, Y.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Chow, J.; Christensen, N.; Chu, Q.; Chua, S. S. Y.; Chung, S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Collette, C.; Colombini, M.; Cominsky, L.; Constancio, M., Jr.; Conte, A.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corpuz, A.; Corsi, A.; Costa, C. A.; Coughlin, M. W.; Coughlin, S.; Coulon, J.-P.; Countryman, S.; Couvares, P.; Coward, D. M.; Cowart, M.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dahl, K.; Dal Canton, T.; Damjanic, M.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Dattilo, V.; Daveloza, H.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; Dayanga, T.; Debreczeni, G.; Degallaix, J.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dereli, H.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Dhurandhar, S.; Díaz, M.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; Di Virgilio, A.; Donath, A.; Donovan, F.; Dooley, K. L.; Doravari, S.; Dossa, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dwyer, S.; Eberle, T.; Edo, T.; Edwards, M.; Effler, A.; Eggenstein, H.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Endrőczi, G.; Essick, R.; Etzel, T.; Evans, M.; Evans, T.; Factourovich, M.; Fafone, V.; Fairhurst, S.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Favata, M.; Fehrmann, H.; Fejer, M. M.; Feldbaum, D.; Feroz, F.; Ferrante, I.; Ferrini, F.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Fisher, R. P.; Flaminio, R.; Fournier, J.-D.; Franco, S.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gair, J.; Gammaitoni, L.; Gaonkar, S.; Garufi, F.; Gehrels, N.; Gemme, G.; Genin, E.; Gennai, A.; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, C.; Gleason, J.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gordon, N.; Gorodetsky, M. L.; Gossan, S.; Goßler, S.; Gouaty, R.; Gräf, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Groot, P.; Grote, H.; Grover, K.; Grunewald, S.; Guidi, G. M.; Guido, C.; Gushwa, K.; Gustafson, E. K.; Gustafson, R.; Hammer, D.; Hammond, G.; Hanke, M.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hart, M.; Hartman, M. T.; Haster, C.-J.; Haughian, K.; Heidmann, A.; Heintze, M.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Heptonstall, A. W.; Heurs, M.; Hewitson, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Hooper, S.; Hopkins, P.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hu, Y.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh, M.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Iyer, B. R.; Izumi, K.; Jacobson, M.; James, E.; Jang, H.; Jaranowski, P.; Ji, Y.

    2014-06-01

    The Numerical INJection Analysis (NINJA) project is a collaborative effort between members of the numerical relativity and gravitational-wave (GW) astrophysics communities. The purpose of NINJA is to study the ability to detect GWs emitted from merging binary black holes (BBH) and recover their parameters with next-generation GW observatories. We report here on the results of the second NINJA project, NINJA-2, which employs 60 complete BBH hybrid waveforms consisting of a numerical portion modelling the late inspiral, merger, and ringdown stitched to a post-Newtonian portion modelling the early inspiral. In a ‘blind injection challenge’ similar to that conducted in recent Laser Interferometer Gravitational Wave Observatory (LIGO) and Virgo science runs, we added seven hybrid waveforms to two months of data recoloured to predictions of Advanced LIGO (aLIGO) and Advanced Virgo (AdV) sensitivity curves during their first observing runs. The resulting data was analysed by GW detection algorithms and 6 of the waveforms were recovered with false alarm rates smaller than 1 in a thousand years. Parameter-estimation algorithms were run on each of these waveforms to explore the ability to constrain the masses, component angular momenta and sky position of these waveforms. We find that the strong degeneracy between the mass ratio and the BHs’ angular momenta will make it difficult to precisely estimate these parameters with aLIGO and AdV. We also perform a large-scale Monte Carlo study to assess the ability to recover each of the 60 hybrid waveforms with early aLIGO and AdV sensitivity curves. Our results predict that early aLIGO and AdV will have a volume-weighted average sensitive distance of 300 Mpc (1 Gpc) for 10M⊙ + 10M⊙ (50M⊙ + 50M⊙) BBH coalescences. We demonstrate that neglecting the component angular momenta in the waveform models used in matched-filtering will result in a reduction in sensitivity for systems with large component angular momenta. This

  6. The Effects of Revealed Information on Catastrophe Loss Projection Models' Characterization of Risk: Damage Vulnerability Evidence from Florida.

    Science.gov (United States)

    Karl, J Bradley; Medders, Lorilee A; Maroney, Patrick F

    2016-06-01

    We examine whether the risk characterization estimated by catastrophic loss projection models is sensitive to the revelation of new information regarding risk type. We use commercial loss projection models from two widely employed modeling firms to estimate the expected hurricane losses of Florida Atlantic University's building stock, both including and excluding secondary information regarding hurricane mitigation features that influence damage vulnerability. We then compare the results of the models without and with this revealed information and find that the revelation of additional, secondary information influences modeled losses for the windstorm-exposed university building stock, primarily evidenced by meaningful percent differences in the loss exceedance output indicated after secondary modifiers are incorporated in the analysis. Secondary risk characteristics for the data set studied appear to have substantially greater impact on probable maximum loss estimates than on average annual loss estimates. While it may be intuitively expected for catastrophe models to indicate that secondary risk characteristics hold value for reducing modeled losses, the finding that the primary value of secondary risk characteristics is in reduction of losses in the "tail" (low probability, high severity) events is less intuitive, and therefore especially interesting. Further, we address the benefit-cost tradeoffs that commercial entities must consider when deciding whether to undergo the data collection necessary to include secondary information in modeling. Although we assert the long-term benefit-cost tradeoff is positive for virtually every entity, we acknowledge short-term disincentives to such an effort. © 2015 Society for Risk Analysis.

  7. Microwave-assisted headspace single-drop microextration of chlorobenzenes from water samples.

    Science.gov (United States)

    Vidal, Lorena; Domini, Claudia E; Grané, Nuria; Psillakis, Elefteria; Canals, Antonio

    2007-05-29

    A one-step and in-situ sample preparation method used for quantifying chlorobenzene compounds in water samples has been developed, coupling microwave and headspace single-drop microextraction (MW-HS-SDME). The chlorobenzenes in water samples were extracted directly onto an ionic liquid single-drop in headspace mode under the aid of microwave radiation. For optimization, a Plackett-Burman screening design was initially used, followed by a mixed-level factorial design. The factors considered were: drop volume, aqueous sample volume, stirring speed, ionic strength, extraction time, ionic liquid type, microwave power and length of the Y-shaped glass-tube. The optimum experimental conditions found from this statistical evaluation were: a 5 microL microdrop of 1-hexyl-3-methylimidazolium hexafluorophosphate exposed for 20 min to the headspace of a 30 mL aqueous sample, irradiated by microwaves at 200 W and placed in a 50 mL spherical flask connected to a 25 cm Y-shaped glass-tube. Under the optimised experimental conditions, the response of a high performance liquid chromatographic system was found to be linear over the range studied and with correlation coefficients ranging between 0.9995 and 0.9999. The method showed a good level of repeatability, with relative standard deviations varying between 2.3 and 8.3% (n=5). Detection limits were found in the low microg L(-1) range varying between 0.016 and 0.039 microg L(-1). Overall, the performance of the proposed method demonstrated the favourable effect of microwave sample irradiation upon HS-SDME. Finally, recovery studies from different types of environmental water samples revealed that matrix had little effect upon extraction.

  8. Microwave-assisted headspace single-drop microextration of chlorobenzenes from water samples

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, Lorena [Departamento de Quimica Analitica, Nutricion y Bromatologia, Universidad de Alicante, P.O. Box 99, E-03080 Alicante (Spain); Domini, Claudia E. [Departamento de Quimica Analitica, Nutricion y Bromatologia, Universidad de Alicante, P.O. Box 99, E-03080 Alicante (Spain); Grane, Nuria [Departamento de Quimica Analitica, Nutricion y Bromatologia, Universidad de Alicante, P.O. Box 99, E-03080 Alicante (Spain); Psillakis, Elefteria [Department of Environmental Engineering, Technical University of Crete, Polytechneioupolis, GR-73100 Chania, Crete (Greece); Canals, Antonio [Departamento de Quimica Analitica, Nutricion y Bromatologia, Universidad de Alicante, P.O. Box 99, E-03080 Alicante (Spain)]. E-mail: a.canals@ua.es

    2007-05-29

    A one-step and in-situ sample preparation method used for quantifying chlorobenzene compounds in water samples has been developed, coupling microwave and headspace single-drop microextraction (MW-HS-SDME). The chlorobenzenes in water samples were extracted directly onto an ionic liquid single-drop in headspace mode under the aid of microwave radiation. For optimization, a Plackett-Burman screening design was initially used, followed by a mixed-level factorial design. The factors considered were: drop volume, aqueous sample volume, stirring speed, ionic strength, extraction time, ionic liquid type, microwave power and length of the Y-shaped glass-tube. The optimum experimental conditions found from this statistical evaluation were: a 5 {mu}L microdrop of 1-hexyl-3-methylimidazolium hexafluorophosphate exposed for 20 min to the headspace of a 30 mL aqueous sample, irradiated by microwaves at 200 W and placed in a 50 mL spherical flask connected to a 25 cm Y-shaped glass-tube. Under the optimised experimental conditions, the response of a high performance liquid chromatographic system was found to be linear over the range studied and with correlation coefficients ranging between 0.9995 and 0.9999. The method showed a good level of repeatability, with relative standard deviations varying between 2.3 and 8.3% (n = 5). Detection limits were found in the low {mu}g L{sup -1} range varying between 0.016 and 0.039 {mu}g L{sup -1}. Overall, the performance of the proposed method demonstrated the favourable effect of microwave sample irradiation upon HS-SDME. Finally, recovery studies from different types of environmental water samples revealed that matrix had little effect upon extraction.

  9. Determination of residual isobutylene oxide--a genotoxic starting material in a drug substance by static headspace gas chromatography.

    Science.gov (United States)

    Han, Jun; Yeung, David; Wang, Fang; Semin, David

    2008-08-01

    A sensitive static headspace gas chromatography (sHS-GC) method is developed and validated for the determination of residual isobutylene oxide (IBO)-a genotoxic starting material in a drug substance for Phase I clinical trial studies. The experimental parameters, such as headspace vial pressure, headspace oven temperature, vial equilibration time, column flow rate, and GC oven temperature programs are optimized. Under the optimal conditions, the recovery is between 89.3% and 102.4% for spiked samples at three levels of IBO concentration in triplicates in sample preparations. Limits of quantitation (LOQ) and detection (LOD) of the standard solutions are 0.048 and 0.018 microg/mL, respectively. Linear range from 0.018 to 6 microg/mL is obtained with a correlation coefficient of 0.9999. The method is applied to determine residual IBO in drug substance samples from different batches.

  10. Headspace solvent microextraction-gas chromatography-mass spectrometry for the analysis of volatile compounds from Foeniculum vulgare Mill.

    Science.gov (United States)

    Fang, Lianghua; Qi, Meiling; Li, Ting; Shao, Qinglong; Fu, Ruonong

    2006-06-07

    A novel and rapid headspace solvent microextraction followed by gas chromatography-mass spectrometry (HSME-GC-MS) for the analysis of the volatile compounds of Foeniculum vulgare Mill is described. HSME parameters including extracting solvent, extraction temperature and time, headspace volume and particle size were optimized. As a result, benzyl alcohol was finally used for the extraction at 70 degrees C for 20 min with headspace volume of 12.1 ml and particle size of 120 mesh. Under the determined conditions, the powered samples of Foeniculum vulgare Mill were directly applied for the analysis. A comparison of HSME-GC-MS, solid phase microextraction (SPME)-GC-MS and steam distillation (SD)-GC-MS methods was made and showed that the HSME-GC-MS method was simple, inexpensive and effective and can be used for the analysis of volatile compounds in traditional Chinese medicines (TCMs).

  11. Dynamic headspace: a single-step extraction for isotopic analysis of microg/L concentrations of dissolved chlorinated ethenes.

    Science.gov (United States)

    Morrill, Penny L; Lacrampe-Couloume, Georges; Lollar, Barbara Sherwood

    2004-01-01

    In this study a dynamic headspace method was developed to measure the carbon isotope values of dissolved chlorinated ethenes at microg/L concentrations. A gas chromatograph/combustion/isotope ratio mass spectrometer (GC/C/IRMS) was modified to include a headspace extraction system followed by a cryogenic trap. Extracting headspace from a 160 mL vial with 80 mL of aqueous solution and 40 g of NaCl for 8-12 min resulted in accurate and reproducible delta13C values for trichloroethene (TCE) and cis-1,2-dichloroethene (cDCE) at concentrations of 50-75 microg/L. Based on these results a conservative lower limit of quantitation of 38 microg/L can be calculated for these compounds. For more volatile compounds such as tetrachloroethene (PCE) and vinyl chloride (VC), field data analyzed using this method indicate a lower limit of quantitation in the tens of microg /L range.

  12. Analysis of Cyanide in Blood by Headspace-Isotope-Dilution-GC-MS

    DEFF Research Database (Denmark)

    Løbger, Lise Lotte; Petersen, Henning Willads; Andersen, Jens Enevold Thaulov

    2008-01-01

    An uncomplicated, rapid, automated procedure for the analysis of low cyanide concentrations in whole blood is reported. The analysis was performed by headspace gas chromatography and mass spectrometry in the (1H12C14N) and m/z 29 (1H13C15N). Carryover from cyanide adsorption onto the surface...... of the needle was prevented by developing a new method that enabled automated flushing of the needle in between each cyanide analysis. Results were compared of ordinary calibrations and those of isotope dilutions. The total time of analysis was 18min for a single cyanide analysis....

  13. Optimizing headspace sampling temperature and time for analysis of volatile oxidation products in fish oil

    DEFF Research Database (Denmark)

    Rørbæk, Karen; Jensen, Benny

    1997-01-01

    Headspace-gas chromatography (HS-GC), based on adsorption to Tenax GR(R), thermal desorption and GC, has been used for analysis of volatiles in fish oil. To optimize sam sampling conditions, the effect of heating the fish oil at various temperatures and times was evaluated from anisidine values (......) and HS-CC. AV indicated sample degradations at 90 degrees C but only small alterations between 60 and 75 degrees C. HS-GC showed increasing response with temperature and rime. Purging at 75 degrees C for 45 min was selected as the preferred sampling condition for oxidized fish oil....

  14. SIMPLE EXTRACTION OF GAMMA-HYDROXYBUTYRATE IN HUMAN WHOLE BLOOD BY HEADSPACE SOLID-PHASE MICROEXTRACTION

    OpenAIRE

    2001-01-01

    We have developed a simple method for the extraction of gamma-hydroxybutyrate (GHB) in human whole blood using headspace solid-phase microextraction (SPME). The procedure involves the conversion of GHB to gamma-butyrolactone (GBL) with acid catalysis; gamma-valerolactone (GVL) was used as internal standard (IS). After heating a vial containing a whole blood sample with GHB and IS at 80℃ for 5 min in the presence of H3PO4 solution, a Carboxen/polydimethylsiloxane -coated fiber was exposed to t...

  15. Isolation and quantification of volatiles in fish by dynamic headspace sampling and mass spectrometry

    DEFF Research Database (Denmark)

    Refsgaard, Hanne; Haahr, Anne-Mette; Jensen, Benny

    1999-01-01

    determined by use of this sample preparation method and for samples chewed for 10 s. Effects of sampling time, temperature, and purge flow on level of volatiles were tested. Purging at 340 mL/min for 30 min at 45 degrees C was found to be optimal. Detection Emits for a number of aldehydes were 0.2-2.7 mu g......A dynamic headspace sampling method for isolation of volatiles in fish has been developed. The sample preparation involved freezing of fish tissue in liquid nitrogen, pulverizing the tissue, and sampling of volatiles from an aqueous slurry of the fish powder. Similar volatile patterns were...

  16. Headspace single drop microextraction coupled with microwave extraction of essential oil from plant materials.

    Science.gov (United States)

    Zhai, Yujuan; Sun, Shuo; Wang, Ziming; Zhang, Yupu; Liu, He; Sun, Ye; Zhang, Hanqi; Yu, Aimin

    2011-05-01

    Headspace single drop microextraction (HS-SDME) coupled with microwave extraction (ME) was developed and applied to the extraction of the essential oil from dried Syzygium aromaticum (L.) Merr. et Perry and Cuminum cyminum L. The operational parameters, such as microdrop volume, microwave absorption medium (MAM), extraction time, and microwave power were optimized. Ten microliters of decane was used as the microextraction solvent. Ionic liquid and carbonyl iron powder were used as MAM. The extraction time was less than 7 min at the microwave power of 440 W. The proposed method was compared with hydrodistillation (HD). There were no obvious differences in the constituents of essential oils obtained by the two methods.

  17. Analysis of Furaneol in tomato using dynamic headspace sampling with sodium sulfate.

    Science.gov (United States)

    Buttery, R G; Takeoka, G R; Naim, M; Rabinowitch, H; Nam, Y

    2001-09-01

    High-flow dynamic headspace sampling with excess anhydrous sodium sulfate was found to be an effective method of isolating Furaneol from fresh tomatoes. Quantitative analysis was carried out by gas chromatography using maltol as internal standard. Furaneol was found in the highest concentrations (660-1100 ppb) in the summer crop of home-grown tomatoes and in some of the greenhouse hydroponically grown tomatoes, which are ripened on the plant before being transported to the supermarkets. Furaneol was found in the lowest concentrations (38-180 ppb) in the common ethylene-ripened, field-grown, supermarket tomatoes.

  18. Specific determination of benzene in urine using dynamic headspace and mass-selective detection.

    Science.gov (United States)

    Ljungkvist, G; Lärstad, M; Mathiasson, L

    1999-01-08

    A method for the determination of benzene in urine was developed, based on dynamic headspace and preconcentration of the analyte on a solid sorbent. The subsequent analysis by thermal desorption of the sorbent, capillary gas chromatography and mass-selective detection ascertained a low limit of detection (6.5 ng/l) and a highly specific determination. The limit of detection is an order of magnitude lower than that reported earlier and allows reliable quantitation of occupational exposure and of most environmental exposures. Samples could be stored frozen for at least a month without significant loss.

  19. Characterization of the disturbed zone in a large rock excavation for the Three Gorges Project

    Energy Technology Data Exchange (ETDEWEB)

    Deng, J.H.; Ge, X.R. [Chinese Academy of Sciences, Wuhan (China); Lee, C.F. [Hong Kong Univ., (China)

    2001-02-01

    In situ studies were conducted in the navigation structures of China's Three Gorges Project. The navigation structures included the permanent shiplock, the shiplift and the temporary shiplock located on the left bank of the Yangtze River. Each of the structures was constructed by deep excavation into the plagioclase granite basement rock to maximum depths of 173.5, 140 and 86 m respectively. A comprehensive study was conducted to determine the mechanical properties and the actual extent of the weakened or disturbed zones. It was determined that excavation in a rock mass results in the disturbance of the stress regime, and creates a stress-relieved, locally weakened zone. The two types of geological and geophysical tests used to determine the vertical extent of this disturbed or weakened zone were the cross-hole seismic wave penetration test and the borehole elastic modulus test. The deformation characteristics were monitored and evaluated to determine the horizontal extent of the weakened zone. It was shown that the P-wave velocity in the disturbed zone was reduced by 34-38 per cent compared to an undisturbed rock. Similarly, the P-wave in the borehole elastic modulus was reduced by 12-31 per cent. This reduction resulted from local sliding along the structural planes which created an opening in the primary structural planes. No newly formed fracture planes were found in the weakened zones. The disturbed zone was compared with both the tensile stress zones and the shear-damaged zones calculated by the finite element method. A reinforcement plan using cable bolts or conventional rock bolts anchored into the undisturbed basement rock was recommended. 4 refs., 5 tabs., 17 figs.

  20. Preparation and Characterization of Uranium Oxides in Support of the K Basin Sludge Treatment Project

    Energy Technology Data Exchange (ETDEWEB)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2008-07-08

    Uraninite (UO2) and metaschoepite (UO3·2H2O) are the uranium phases most frequently observed in K Basin sludge. Uraninite arises from the oxidation of uranium metal by anoxic water and metaschoepite arises from oxidation of uraninite by atmospheric or radiolytic oxygen. Studies of the oxidation of uraninite by oxygen to form metaschoepite were performed at 21°C and 50°C. A uranium oxide oxidation state characterization method based on spectrophotometry of the solution formed by dissolving aqueous slurries in phosphoric acid was developed to follow the extent of reaction. This method may be applied to determine uranium oxide oxidation state distribution in K Basin sludge. The uraninite produced by anoxic corrosion of uranium metal has exceedingly fine particle size (6 nm diameter), forms agglomerates, and has the formula UO2.004±0.007; i.e., is practically stoichiometric UO2. The metaschoepite particles are flatter and wider when prepared at 21°C than the particles prepared at 50°C. These particles are much smaller than the metaschoepite observed in prolonged exposure of actual K Basin sludge to warm moist oxidizing conditions. The uraninite produced by anoxic uranium metal corrosion and the metaschoepite produced by reaction of uraninite aqueous slurries with oxygen may be used in engineering and process development testing. A rapid alternative method to determine uranium metal concentrations in sludge also was identified.

  1. Yucca Mountain Project thermal and mechanical codes first benchmark exercise: Part 3, Jointed rock mass analysis; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Costin, L.S.; Bauer, S.J.

    1991-10-01

    Thermal and mechanical models for intact and jointed rock mass behavior are being developed, verified, and validated at Sandia National Laboratories for the Yucca Mountain Site Characterization Project. Benchmarking is an essential part of this effort and is one of the tools used to demonstrate verification of engineering software used to solve thermomechanical problems. This report presents the results of the third (and final) phase of the first thermomechanical benchmark exercise. In the first phase of this exercise, nonlinear heat conduction code were used to solve the thermal portion of the benchmark problem. The results from the thermal analysis were then used as input to the second and third phases of the exercise, which consisted of solving the structural portion of the benchmark problem. In the second phase of the exercise, a linear elastic rock mass model was used. In the third phase of the exercise, two different nonlinear jointed rock mass models were used to solve the thermostructural problem. Both models, the Sandia compliant joint model and the RE/SPEC joint empirical model, explicitly incorporate the effect of the joints on the response of the continuum. Three different structural codes, JAC, SANCHO, and SPECTROM-31, were used with the above models in the third phase of the study. Each model was implemented in two different codes so that direct comparisons of results from each model could be made. The results submitted by the participants showed that the finite element solutions using each model were in reasonable agreement. Some consistent differences between the solutions using the two different models were noted but are not considered important to verification of the codes. 9 refs., 18 figs., 8 tabs.

  2. Uncertainty of Blood Alcohol Concentration (BAC Results as Related to Instrumental Conditions: Optimization and Robustness of BAC Analysis Headspace Parameters

    Directory of Open Access Journals (Sweden)

    Haleigh A. Boswell

    2015-12-01

    Full Text Available Analysis of blood alcohol concentration is a routine analysis performed in many forensic laboratories. This analysis commonly utilizes static headspace sampling, followed by gas chromatography combined with flame ionization detection (GC-FID. Studies have shown several “optimal” methods for instrumental operating conditions, which are intended to yield accurate and precise data. Given that different instruments, sampling methods, application specific columns and parameters are often utilized, it is much less common to find information on the robustness of these reported conditions. A major problem can arise when these “optimal” conditions may not also be robust, thus producing data with higher than desired uncertainty or potentially inaccurate results. The goal of this research was to incorporate the principles of quality by design (QBD in the adjustment and determination of BAC (blood alcohol concentration instrumental headspace parameters, thereby ensuring that minor instrumental variations, which occur as a matter of normal work, do not appreciably affect the final results of this analysis. This study discusses both the QBD principles as well as the results of the experiments, which allow for determination of more favorable instrumental headspace conditions. Additionally, method detection limits will also be reported in order to determine a reporting threshold and the degree of uncertainty at the common threshold value of 0.08 g/dL. Furthermore, the comparison of two internal standards, n-propanol and t-butanol, will be investigated. The study showed that an altered parameter of 85 °C headspace oven temperature and 15 psi headspace vial pressurization produces the lowest percent relative standard deviation of 1.3% when t-butanol is implemented as an internal standard, at least for one very common platform. The study also showed that an altered parameter of 100 °C headspace oven temperature and 15-psi headspace vial pressurization

  3. SYSTHESIS OF VOLCANISM STUDIES FOR THE YUCCA MOUNTAIN SITE CHARACTERIZATION PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Perry, F. V.; Crowe, G. A.; Valentine, G. A.; Bowker, L. M.

    1997-09-23

    This report synthesizes the results of volcanism studies conducted by scientists at the Los Alamos National Laboratory and collaborating institutions on behalf of the Department of Energy's Yucca Mountain Project. Chapter 1 introduces the volcanism issue for the Yucca Mountain site and provides the reader with an overview of the organization, content, and significant conclusions of this report. The hazard of future basaltic volcanism is the primary topic of concern including both events that intersect a potential repository and events that occur near or within the waste isolation system of a repository. Future volcanic events cannot be predicted with certainty but instead are estimated using formal methods of probabilistic volcanic hazard assessment (PVHA). Chapter 2 describes the volcanic history of the Yucca Mountain region (YMR) and emphasizes the Pliocene and Quaternary volcanic record, the interval of primary concern for volcanic risk assessment. The distribution, eruptive history, and geochronology of Plio-Quaternary basalt centers are described by individual center emphasizing the younger postcaldera basalt (<5 Ma). The Lathrop Wells volcanic center is described in detail because it is the youngest basalt center in the YMR. The age of the Lathrop Wells center is now confidently determined to be about 75 thousand years old. Chapter 3 describes the tectonic setting of the YMR and presents and assesses the significance of multiple alternative tectonic models. The distribution of Pliocene and Quaternary basaltic volcanic centers is evaluated with respect to tectonic models for detachment, caldera, regional and local rifting, and the Walker Lane structural zone. Geophysical data are described for the YMR and are used as an aid to understand the distribution of past basaltic volcanic centers and possible future magmatic processes. Chapter 4 discusses the petrologic and geochemical features of basaltic volcanism in the YMR, the southern Great Basin and the

  4. SYSTHESIS OF VOLCANISM STUDIES FOR THE YUCCA MOUNTAIN SITE CHARACTERIZATION PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Perry, F. V.; Crowe, G. A.; Valentine, G. A.; Bowker, L. M.

    1997-09-23

    This report synthesizes the results of volcanism studies conducted by scientists at the Los Alamos National Laboratory and collaborating institutions on behalf of the Department of Energy's Yucca Mountain Project. Chapter 1 introduces the volcanism issue for the Yucca Mountain site and provides the reader with an overview of the organization, content, and significant conclusions of this report. The hazard of future basaltic volcanism is the primary topic of concern including both events that intersect a potential repository and events that occur near or within the waste isolation system of a repository. Future volcanic events cannot be predicted with certainty but instead are estimated using formal methods of probabilistic volcanic hazard assessment (PVHA). Chapter 2 describes the volcanic history of the Yucca Mountain region (YMR) and emphasizes the Pliocene and Quaternary volcanic record, the interval of primary concern for volcanic risk assessment. The distribution, eruptive history, and geochronology of Plio-Quaternary basalt centers are described by individual center emphasizing the younger postcaldera basalt (<5 Ma). The Lathrop Wells volcanic center is described in detail because it is the youngest basalt center in the YMR. The age of the Lathrop Wells center is now confidently determined to be about 75 thousand years old. Chapter 3 describes the tectonic setting of the YMR and presents and assesses the significance of multiple alternative tectonic models. The distribution of Pliocene and Quaternary basaltic volcanic centers is evaluated with respect to tectonic models for detachment, caldera, regional and local rifting, and the Walker Lane structural zone. Geophysical data are described for the YMR and are used as an aid to understand the distribution of past basaltic volcanic centers and possible future magmatic processes. Chapter 4 discusses the petrologic and geochemical features of basaltic volcanism in the YMR, the southern Great Basin and the

  5. headspace: National Youth Mental Health Foundation: making headway with rural young people and their mental health.

    Science.gov (United States)

    Hodges, Craig A; O'Brien, Matthew S; McGorry, Patrick D

    2007-04-01

    Mental health is the number one health issue affecting young people in Australia today, yet only one in four of these young people receive professional help. Approximately 14% of 12- to 17-year-olds and 27% of 18- to 25-year-olds experience mental health problems each year. However, many do not have ready access to treatment or are reluctant to seek that help. These issues might be exacerbated in the rural and remote regions of Australia where sociocultural barriers such as stigma, lack of anonymity and logistic difficulties including cost and availability of transport can hinder young people accessing mental health services. headspace: the National Youth Mental Health Foundation has been funded to address these issues. headspace will provide funding for the establishment of communities of youth services across Australia, provide national and local community awareness campaigns and plans, establish a centre of excellence that will identify and disseminate evidence-based practice in addressing youth mental health issues, and translate findings into education and training programs that are targeted at service providers to work with youth mental health. The communities of youth services will build the capacity of local communities to identify early, and provide effective responses to, young people aged 12-25 years with mental health and related substance use disorders. Specific approaches in rural, regional and remote areas will be developed as well as specific programs to involve young Indigenous people.

  6. Grains colonised by moulds: fungal identification and headspace analysis of produced volatile metabolites

    Directory of Open Access Journals (Sweden)

    Maria Paola Tampieri

    2010-01-01

    Full Text Available The aim of this work was to verify if the headspace analysis of fungal volatile compounds produced by some species of Fusarium can be used as a marker of mould presence on maize. Eight samples of maize (four yellow maize from North Italy and four white maize from Hungary, naturally contaminated by Fusarium and positive for the presence of fumonisins, were analyzed to detect moisture content, Aw, volatile metabolites and an enumeration of viable moulds was performed by means of a colony count technique. Headspace samples were analysed using a gas-chromatograph equipped with a capillary column TR-WAX to detect volatile metabolites of moulds. Furthermore macro and microscopic examination of the colonies was performed in order to distinguish, according to their morphology, the genera of the prevalent present moulds. Prevalent mould of eight samples was Fusarium, but other fungi, like Aspergillus, Penicillum and Mucoraceae, were observed. The metabolites produced by F.graminearum and F. moniliforme were Isobutyl-acetate, 3-Methyl-1-butanol and, only at 8 days, 3-Octanone. The incubation time can affect off flavour production in consequence of the presence of other moulds. Further studies on maize samples under different conditions are needed in order to establish the presence of moulds using the count technique and through the identification of volatile compounds.

  7. Determination of dissolved methane in natural waters using headspace analysis with cavity ring-down spectroscopy.

    Science.gov (United States)

    Roberts, Hannah M; Shiller, Alan M

    2015-01-26

    Methane (CH4) is the third most abundant greenhouse gas (GHG) but is vastly understudied in comparison to carbon dioxide. Sources and sinks to the atmosphere vary considerably in estimation, including sources such as fresh and marine water systems. A new method to determine dissolved methane concentrations in discrete water samples has been evaluated. By analyzing an equilibrated headspace using laser cavity ring-down spectroscopy (CRDS), low nanomolar dissolved methane concentrations can be determined with high reproducibility (i.e., 0.13 nM detection limit and typical 4% RSD). While CRDS instruments cost roughly twice that of gas chromatographs (GC) usually used for methane determination, the process presented herein is substantially simpler, faster, and requires fewer materials than GC methods. Typically, 70-mL water samples are equilibrated with an equivalent amount of zero air in plastic syringes. The equilibrated headspace is transferred to a clean, dry syringe and then drawn into a Picarro G2301 CRDS analyzer via the instrument's pump. We demonstrate that this instrument holds a linear calibration into the sub-ppmv methane concentration range and holds a stable calibration for at least two years. Application of the method to shipboard dissolved methane determination in the northern Gulf of Mexico as well as river water is shown. Concentrations spanning nearly six orders of magnitude have been determined with this method.

  8. River water quality analysis via headspace detection of volatile organic compounds

    Science.gov (United States)

    Tang, Johnny Jock Lee; Nishi, Phyllis Jacqueline; Chong, Gabriel Eng Wee; Wong, Martin Gideon; Chua, Hong Siang; Persaud, Krishna; Ng, Sing Muk

    2017-03-01

    Human civilization has intensified the interaction between the community and the environment. This increases the threat on the environm ent for being over exploited and contaminated with m anmade products and synthetic chemicals. Of all, clean water is one of the resources that can be easily contaminated since it is a universal solvent and of high mobility. This work reports the development and optimization of a water quality monitoring system based on metal oxide sensors. The system is intended to a ssist the detection of volatile organic compounds (VOCs) present in water sources online and onsite. The sampling mechanism was based on contactless mode, where headspace partial pressure of the VOCs formed above the water body in a close chamber was drawn for detection at the sensor platform. Pure toluene was used as standard to represent the broad spectrum of VOCs, and the sensor dynamic range was achieved from 1-1000 ppb. Several sensing parameters such as sampling time, headspace volume, and sensor recovery were s tudied and optimized. Besides direct detection of VOC contaminants in the water, the work has also been extended to detect VOCs produced by microbial communities and to c orrelate the size of the communities with the reading of V OCs recorded. This can serve to give b etter indication of water quality, not only on the conce ntration of VOCs c ontamination from chemicals, but also the content of microbes, which some can have severe effect on human health.

  9. Brain and Liver Headspace Aldehyde Concentration Following Dietary Supplementation with n-3 Polyunsaturated Fatty Acids.

    Science.gov (United States)

    Ross, Brian M; Babay, Slim; Malik, Imran

    2015-11-01

    Reactive oxygen species react with unsaturated fatty acids to form a variety of metabolites including aldehydes. Many aldehydes are volatile enough to be detected in headspace gases of blood or cultured cells and in exhaled breath, in particular propanal and hexanal which are derived from omega-3 and omega-6 polyunsaturated fatty acids, respectively. Aldehydes are therefore potential non-invasive biomarkers of oxidative stress and of various diseases in which oxidative stress is thought to play a role including cancer, cardiovascular disease and diabetes. It is unclear, however, how changes in the abundance of the fatty acid precursors, for example by altered dietary intake, affect aldehyde concentrations. We therefore fed male Wistar rats diets supplemented with either palm oil or a combination of palm oil plus an n-3 fatty acid (alpha-linolenic, eicosapentaenoic, or docosahexaenoic acids) for 4 weeks. Fatty acid analysis revealed large changes in the abundance of both n-3 and n-6 fatty acids in the liver with smaller changes observed in the brain. Despite the altered fatty acid abundance, headspace concentrations of C1-C8 aldehydes, and tissue concentrations of thiobarbituric acid reactive substances, did not differ between the 4 dietary groups. Our data suggest that tissue aldehyde concentrations are independent of fatty acid abundance, and further support their use as volatile biomarkers of oxidative stress.

  10. Rapid determination of methanol content in paper materials by alkaline extraction, coupled with headspace analysis.

    Science.gov (United States)

    Zhang, Chun-Yun; Li, Ling-Ling; Chai, Xin-Sheng; Barnes, Donald G

    2014-07-11

    This study reports on a rapid method for the determination of methanol in paper-based materials by alkaline extraction, coupled with headspace analysis. Methanol partition equilibria between solid-liquid phases and vapor-liquid phases were conducted in two separate containers, from which an equation for calculating the total methanol content in the original paper sample was derived. It was found that the extraction equilibrium of methanol from solid sample could be achieved within 5min at room temperature using a high-speed disintegrator, and a subsequent neutralization step is an effective way to prevent methanol from being regenerated at high temperature during headspace equilibration. The results showed that the relative standard deviations for reproducibility tests were in the range of 1.86-6.03%, and the recoveries were in the range of 92.3-107%. The present method is simple and practical; it can be an efficient tool for quantifying the methanol content in paper-based materials and thus play an important role in the investigation of methanol migration behavior in food and beverage packaging.

  11. Quantitative analysis of total starch content in wheat flour by reaction headspace gas chromatography.

    Science.gov (United States)

    Xie, Wei-Qi; Gong, Yi-Xian; Yu, Kong-Xian

    2017-07-10

    This paper proposed a new reaction headspace gas chromatographic (HS-GC) method for efficiently quantifying the total starch content in wheat flours. A certain weight of wheat flour was oxidized by potassium dichromate in an acidic condition in a sealed headspace vial. The results show that the starch in wheat flour can be completely transferred to carbon dioxide at the given conditions (at 100 °C for 40 min) and the total starch content in wheat flour sample can be indirectly quantified by detecting the CO2 formed from the oxidation reaction. The data showed that the relative standard deviation of the reaction HS-GC method in the precision test was less than 3.06%, and the relative differences between the new method and the reference method (titration method) were no more than 8.90%. The new reaction HS-GC method is automated, accurate, and can be a reliable tool for determining the total starch content in wheat flours in both laboratory and industrial applications. Graphical abstract The total starch content in wheat flour can be indirectly quantified by the GC detection of the CO2 formed from the oxidation reaction between wheat flour and potassium dichromate in an acidic condition.

  12. Calibration of an optical condensate measurement technique using indirect static headspace gas chromatography.

    Science.gov (United States)

    Hoke, P B; Loconto, P R; McGrath, J J

    2001-12-01

    Researchers in the Department of Mechanical Engineering seek to obtain a means to measure less than 3 mg of H2O that adheres to a metal surface as condensate. The objective is to calibrate optical reflectance measurements of an aluminum surface as a function of the condensate thickness present. Collaboration with the Hazardous Substance Research Center at Michigan State University results in the development of an indirect static headspace gas chromatographic technique capable of measuring H2O in low-milligram quantities. The technique utilizes manual headspace sampling, a megabore capillary column, and a flame ionization detector. A correlation of r2 = 0.999 is obtained for the calibration of the indirect measurement technique. The calibration of the analytical instrument demonstrates adequate precision (calcium carbide to convert the H2O to acetylene. A scaled calibration technique is used to simplify handling trace water volumes. The surface reflectance measurements are found to correlate well (r2 = 0.935) with measurements of the condensate mass. This result facilitates the development of an optical mass-transfer measurement technique. This study focuses on the analytical method and its relationship with engineering research.

  13. Characterization of a backfill candidate material, IBECO-RWC-BF Baclo Project - Phase 3 Laboratory tests

    Energy Technology Data Exchange (ETDEWEB)

    Johannesson, Lars-Erik; Sanden, Torbjoern; Dueck, Ann; Ohlsson, Lars (Clay Technology AB, Lund (Sweden))

    2010-01-15

    A backfill candidate material, IBECO-RWC-BF, which origin from Milos, Greece, has been investigated. The material was delivered both as granules and as pellets. The investigation described in this report aimed to characterize the material and evaluate if it can be used in a future repository. The following investigations have been done and are presented in this report: 1. Standard laboratory tests. Water content, liquid limit and swelling potential are examples on standard tests that have been performed. 2. Block manufacturing. The block compaction properties of the material have been determined. A first test was performed in laboratory but also tests in large scale have been performed. After finishing the test phase, 60 tons of blocks were manufactured at Hoeganaes Bjuf AB. The blocks will be used in large scale laboratory tests at Aespoe HRL. 3. Mechanical parameters. The compressibility of the material was investigated with oedometer tests (four tests) where the load was applied in steps after saturation. The evaluated oedometer modulus varied between 34.50 MPa. Tests were made to evaluate the elastic parameters of the material (E, nu). Altogether three tests were made on specimens with dry densities of about 1,710 kg/m3. The evaluated E-modulus and Poisson's ratio varied between 231-263 MPa and 0.16-0.19 respectively. The strength of the material, both the compressive strength and the tensile strength were measured on specimens compacted to different dry densities. The test results yielded a relation between density and the two types of strength. Furthermore, tests have been made in order to determine the compressibility of the unsaturated filling of pellets. Two tests were made where the pellets were loosely filled in a Proctor cylinder and then compressed at a constant rate of strain during continuously measurement of the applied load. 4. Swelling pressure and hydraulic conductivity. There is, as expected, a very clear influence of the dry density on the

  14. Characterization of a backfill candidate material, IBECO-RWC-BF Baclo Project - Phase 3 Laboratory tests

    Energy Technology Data Exchange (ETDEWEB)

    Johannesson, Lars-Erik; Sanden, Torbjoern; Dueck, Ann; Ohlsson, Lars (Clay Technology AB, Lund (Sweden))

    2010-01-15

    A backfill candidate material, IBECO-RWC-BF, which origin from Milos, Greece, has been investigated. The material was delivered both as granules and as pellets. The investigation described in this report aimed to characterize the material and evaluate if it can be used in a future repository. The following investigations have been done and are presented in this report: 1. Standard laboratory tests. Water content, liquid limit and swelling potential are examples on standard tests that have been performed. 2. Block manufacturing. The block compaction properties of the material have been determined. A first test was performed in laboratory but also tests in large scale have been performed. After finishing the test phase, 60 tons of blocks were manufactured at Hoeganaes Bjuf AB. The blocks will be used in large scale laboratory tests at Aespoe HRL. 3. Mechanical parameters. The compressibility of the material was investigated with oedometer tests (four tests) where the load was applied in steps after saturation. The evaluated oedometer modulus varied between 34.50 MPa. Tests were made to evaluate the elastic parameters of the material (E, nu). Altogether three tests were made on specimens with dry densities of about 1,710 kg/m3. The evaluated E-modulus and Poisson's ratio varied between 231-263 MPa and 0.16-0.19 respectively. The strength of the material, both the compressive strength and the tensile strength were measured on specimens compacted to different dry densities. The test results yielded a relation between density and the two types of strength. Furthermore, tests have been made in order to determine the compressibility of the unsaturated filling of pellets. Two tests were made where the pellets were loosely filled in a Proctor cylinder and then compressed at a constant rate of strain during continuously measurement of the applied load. 4. Swelling pressure and hydraulic conductivity. There is, as expected, a very clear influence of the dry density on the

  15. SMART 3D SUBSURFACE CONTAMINANT CHARACTERIZATION AT THE BGRR DECOMMISSIONING PROJECT. ACCELERATED SITE TECHNOLOGY DEPLOYMENT COST AND PERFORMANCE REPORT.

    Energy Technology Data Exchange (ETDEWEB)

    HEISER,J.; KALB,P.; SULLIVAN,T.; MILIAN,L.

    2001-12-01

    The BGRR was the world's first nuclear reactor dedicated to the peaceful exploration of atomic energy. The reactor pile consisted of a 700-ton, 25-foot cube of graphite fueled by uranium. A total of 1,369 fuel channels were available with roughly half in use at any given time. Insertion and removal of boron steel control rods controlled reactor power levels. One or more of five fans powered air-cooling. Air was brought in through two filtered plenums, flowed through and around the reactor core, through an exhaust duct containing filters, and finally out through the 320-foot high exhaust stack. Spent fuel was temporarily stored in the spent-fuel canal, and then sent to the Department of Energy's Savannah River Site (SRS). Access to the canal for removing spent fuel was through the Canal House (Building 709). The BGRR ceased operation in 1968 and was placed in a shutdown mode in which all fuel was removed and sent to SRS. Penetrations in the biological shield around the graphite cube and fuel channels were sealed. The final decontamination and decommissioning (D and D) process was initiated in 1999 and is scheduled for completion in 2005. An accelerated schedule was developed that combines characterization with removal actions for the various systems and structures. Before D and D work on a section of the BGRR facility begins, contaminant characterization is conducted to determine the types and amounts of contaminants present. The data are then used for project planning, including decisions affecting the extent of removal, waste designation, and health and safety plans.

  16. Bromination of Aromatic Compounds by Residual Bromide in Sodium Chloride Matrix Modifier Salt During Heated Headspace GC/MS Analysis

    Science.gov (United States)

    Analytical artifacts attributed to the bromination of toluene, xylenes, and trimethylbenzenes were found during the heated headspace gas chromatography/mass spectrometry (GC/MS) analysis of aqueous samples. The aqueous samples were produced from Fenton-like chemical oxidation rea...

  17. Comparison of tomatillo and tomato volatile compounds in the headspace by selected ion flow tube mass spectrometry (SIFT-MS).

    Science.gov (United States)

    Xu, Yichi; Barringer, Sheryl

    2010-04-01

    The concentration of 31 volatiles were measured in the headspace of tomatillos using selected ion flow tube-mass spectrometry (SIFT-MS), and were compared with those in vine-ripened tomato, roma tomato, cherry tomato, and grape tomato. None of the volatiles were higher in the headspace of tomatillos than of tomatoes. Compounds (E)-2-octenal, (E)-2-pentenal, 2-isobutylthiazole, 6-methyl-5-hepten-2-one, and phenylacetaldehyde were significantly lower in tomatillo than in the tomato varieties in the headspace. After blending, volatiles in the headspace increased, and then decreased after reaching a maximum concentration, due to further degradation or depletion. Compounds (E)-2-pentenal and 1-penten-3-one reached a maximum concentration later than (E)-2-hexenal, (Z)-3-hexenal, and hexanal for tomatillo and tomatoes. The slope of the ratio of (E)-2-hexenal and (Z)-3-hexenal was not significantly different for any of the samples, implying that the activity of cis/trans isomerase was not different between tomatillos and tomatoes.

  18. Application of head-space solid-phase microextraction for the analysis of volatile metabolites emitted by Penicillium species

    DEFF Research Database (Denmark)

    Nilsson, Torben; Larsen, Thomas Ostenfeld; Montanarella, Luca

    1996-01-01

    Head-space solid-phase microextraction (HS-SPME) has been used to collect volatile organic compounds (VOCs) emitted from fungi of the genus Penicillium. Gas chromatography combined with mass spectrometry (GC-MS) was employed for the analysis of the profiles of volatile metabolites characteristic ...

  19. Dynamic headspace-gas-chromatography-olfactometry analysis of different anatomical parts of lovage (Levisticum officinale Koch.) at eight growing stages

    NARCIS (Netherlands)

    Bylaite, E.; Roozen, J.P.; Legger, A.; Venskutonis, R.P.; Posthumus, M.A.

    2000-01-01

    Volatiles of five different parts of lovage (leaves, stems, flowers, seeds, and roots) were isolated by dynamic headspace (DHS) method and analyzed by GC-FID and GC-olfactometry (GC-O) techniques. In total, 98 compounds were identified in the samples, of which 41 are reported as lovage volatiles for

  20. Reference materials and representative test materials to develop nanoparticle characterization methods: the NanoChOp project case

    Science.gov (United States)

    Roebben, Gert; Kestens, Vikram; Varga, Zoltan; Charoud-Got, Jean; Ramaye, Yannic; Gollwitzer, Christian; Bartczak, Dorota; Geißler, Daniel; Noble, James; Mazoua, Stéphane; Meeus, Nele; Corbisier, Philippe; Palmai, Marcell; Mihály, Judith; Krumrey, Michael; Davies, Julie; Resch-Genger, Ute; Kumarswami, Neelam; Minelli, Caterina; Sikora, Aneta; Goenaga-Infante, Heidi

    2015-10-01

    This paper describes the production and characteristics of the nanoparticle test materials prepared for common use in the collaborative research project NanoChOp (Chemical and optical characterisation of nanomaterials in biological systems), in casu suspensions of silica nanoparticles and CdSe/CdS/ZnS quantum dots. This paper is the first to illustrate how to assess whether nanoparticle test materials meet the requirements of a 'reference material' (ISO Guide 30:2015) or rather those of the recently defined category of 'representative test material' (ISO TS 16195:2013). The NanoChOp test materials were investigated with small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and centrifugal liquid sedimentation (CLS) to establish whether they complied with the required monomodal particle size distribution. The presence of impurities, aggregates, agglomerates and viable microorganisms in the suspensions was investigated with DLS, CLS, optical and electron microscopy and via plating on nutrient agar. Suitability of surface functionalization was investigated with attenuated total reflection Fourier transform infrared spectrometry (ATR-FTIR) and via the capacity of the nanoparticles to be fluorescently labeled or to bind antibodies. Between-unit homogeneity and stability were investigated in terms of particle size and zeta potential. This paper shows that only based on the outcome of a detailed characterization process one can raise the status of a test material to representative test material or reference material, and how this status depends on its intended use.

  1. Characterization techniques for nano-electronics, with emphasis to electron microscopy. The role of the European Project ANNA

    Science.gov (United States)

    Armigliato, A.

    2008-07-01

    , however, European laboratories with high-level expertise in materials characterization still operate in a largely independent way; this adversely affects the competitivity of European science and industry at the international level. For this reason the European Commission has started an Integrated Infrastructure Initiative (I3) in the sixth Framework Programme (now continuing in FP7) and funded a project called ANNA (2006-2010). This acronym stands for European Integrated Activity of Excellence and Networking for Nano and Micro- Electronics Analysis. The consortium includes 12 partners from 7 European countries and is coordinated by the Fondazione B.Kessler (FBK) in Trento (Italy); CNR-IMM is one of the 12 partners. Aim of ANNA is the onset of strong, long-term collaboration among the partners, so to form an integrated multi-site analytical facility, able to offer to the European community a wide variety of top-level analytical expertise and services in the field of micro- and nano-electronics. They include X-ray diffraction and scattering, SIMS, electron microscopy, medium-energy ion scattering, optical and electrical techniques. The project will be focused on three main activities: Networking (standardization of samples and methodologies, establishment of accredited reference laboratories), Transnational Access to laboratories located in the partners' premises to perform specific analytical experiments (an example is given by the two STEM methodologies discussed above) and Joint Research activity, which is targeted at the improvement and extension of the methodologies through a continuous instrumental and technical development. It is planned that the European joint analytical laboratory will continue its activity beyond the end of the project in 2010.

  2. Hydrogeological characterization based on the results of long term monitoring in the Mizunami Underground Research Laboratory Project

    Science.gov (United States)

    Takeuchi, R.; Ohyama, T.; Matsuoka, T.; Saegusa, H.; Takeuchi, S.

    2009-12-01

    The Mizunami Underground Research Laboratory (MIU) is now under construction by the Japan Atomic Energy Agency in the Cretaceous Toki granite in the Tono area of central Japan. Conceptual design of the MIU consists of two 1,000 m shafts (the Main Shaft and the Ventilation Shaft) and horizontal research galleries. The MIU project is a broad scientific study of the deep geological environment as a base for the research and development for geological disposal of nuclear wastes. One of the main goals is to establish comprehensive techniques for investigation, analysis and assessment of the deep geological environment in fractured crystalline rock. The project is being implemented in three overlapping phases: Surface-based Investigation (Phase I), Construction (Phase II) and Operation (Phase III), with a total duration of 20 years. In Phase I, surface investigations were carried out in a stepwise manner in order to obtain information of the geological environment at the site scale (about 2km square). Geological modeling and simulations of various kinds had been carried out in order to synthesize these investigation results. Two NNW-trending faults, which are important for hydrogeological characterization, are included in the model. One of the faults (fault A) strikes through the site in the immediate vicinity of the Main Shaft and another fault (fault B) strikes through the southern part of the MIU construction site. In Phase II, field investigations have been carried out in and around the MIU construction site. For hydrogeological characterization, long term monitoring of hydraulic pressure, surface tilt and self-potential have been carried out on surface and in the research galleries to obtain information on changes of groundwater flow due to shaft excavation. The results of the long term monitoring focused on fault A are as follows: - The hydraulic pressure responses are observed in surface boreholes in and around the MIU construction site and the galleries. The

  3. Sample Preparation for Headspace GC Analysis of Residual Solvents in Hyaluronic Acid Derivative Fiber

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hoon Joo; Kim, Dong Min; Yang, Jeong Soo [LG life Sciences, Ltd./R and D Park, Daejeon (Korea, Republic of); Kim, Chan Wha [Korea University, Seoul (Korea, Republic of)

    2006-02-15

    The aim of this study is to develop efficient sample preparation method for HS-GC analysis of residual solvents in HA derivative fiber. Compared to direct extraction of residual solvents from HA derivative fiber, the extraction through the hydrolysis of HA derivative fiber by HAse gave more complete and higher reproducible quantification of residual solvent. To validate HS-GC analysis method of residual solvents, specificity, limits of detection and quantification, linearity, accuracy and precision are investigated in the study. HA derivative fiber was hydrolyzed using HAse for headspace gas chromatographic analysis of residual solvents of ethanol, acetone and isopropanol in HA derivative fiber. This study showed that the developed method had specificity, linearity, accuracy and precision. In addition, it demonstrated that HS-GC coupled with matrix-breaking method such as hydrolysis was available for the determination of residual solvents in a matrix like HA derivative fiber.

  4. Carbon monoxide analysis: a comparison of two co-oximeters and headspace gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Costantino, A.G.; Park, J.; Caplan, Y.H.

    Three methods (lL-182 Co-Oximeter, lL-282 Co-Oximeter, and headspace gas chromatography) for the analysis of carbon monoxide in postmortem blood were studied and compared using a prepared reference standard, Quantra control materials, and 62 postmortem blood specimens. The methods compared favorably with one another. The linear regression equations for the 62 postmortem blood samples (range = 1.0 to 86% saturation) were: lL-282 vs. lL-182, y = 1.11x - 3.10, r = 0.981; lL-182 vs. GC, y = 0.88x + 2.97, r = 0.973; lL-282 vs. GC, y = 1.00x - 1.24, r = 0.986.

  5. Headspace screening: A novel approach for fast quality assessment of the essential oil from culinary sage.

    Science.gov (United States)

    Cvetkovikj, Ivana; Stefkov, Gjoshe; Acevska, Jelena; Karapandzova, Marija; Dimitrovska, Aneta; Kulevanova, Svetlana

    2016-07-01

    Quality assessment of essential oil (EO) from culinary sage (Salvia officinalis L., Lamiaceae) is limited by the long pharmacopoeial procedure. The aim of this study was to employ headspace (HS) sampling in the quality assessment of sage EO. Different populations (30) of culinary sage were assessed using GC/FID/MS analysis of the hydrodistilled EO (pharmacopoeial method) and HS sampling directly from leaves. Compound profiles from both procedures were evaluated according to ISO 9909 and GDC standards for sage EO quality, revealing compliance for only 10 populations. Factors to convert HS values, for the target ISO and GDC components, into theoretical EO values were calculated. Statistical analysis revealed a significant relationship between HS and EO values for seven target components. Consequently, HS sampling could be used as a complementary extraction technique for rapid screening in quality assessment of sage EOs.

  6. Rapid quantification of dimethyl methylphosphonate from activated carbon particles by static headspace gas chromatography mass spectrometry.

    Science.gov (United States)

    Mitchell, Brendan L; Billingsley, Brit G; Logue, Brian A

    2013-06-01

    Activated carbon (AC) particles are utilized as an adsorbent for binding hazardous vapors in protective equipment. The binding affinity and utilization of these AC particles should be known to ensure effective and efficient use. Therefore, a simple and effective method was developed for the quantification of the chemical warfare agent simulant, dimethyl methylphosphonate (DMMP), from AC particles. Static headspace gas chromatography mass-spectrometry with internal standard, DMMP-d6, was used to perform the analysis. The method produced a linear dynamic range of 2.48-620g DMMP/kg carbon and a detection limit of 1.24g DMMP/kg carbon. Furthermore, the method produced a coefficient of variation of less than 16% for all intra- and inter-assay analyses. The method provided a simple and effective procedure for quantifying DMMP from AC particles and was applied to the analysis of a DMMP-exposed AC protective respirator filter.

  7. Storage stability of crips measured by headspace and peroxide value analyses

    Directory of Open Access Journals (Sweden)

    Lahtinen, R. M.

    1996-04-01

    Full Text Available Normal sunflower oil and high oleic acid sunflower oil were tested in industrial frying of crisps against the reference oil palm olein. A protective agent, dimethyl polysiloxane (DMPS, was also tested in crisp frying. Peroxide values and volatile contents of the crisps stored in normal storage conditions (room temperature were measured during storage. From the peroxide values it could be seen that crisps fried in normal sunflower oil were the most unstable during storage. Crisps fried in high oleic sunflower oil proved to be almost as stable towards oxidation as crisps fried in reference oil palm olein. Volatile contents, measured by a static headspace - gas chromatograph - mass spectrometry system, confirmed the conclusions of peroxide analysis. Neither of the methods could find any difference between the samples which had been fried with and without DMPS.

  8. Rapid determination of moisture content in paper materials by multiple headspace extraction gas chromatography.

    Science.gov (United States)

    Xie, Wei-Qi; Chai, Xin-Sheng

    2016-04-22

    This paper describes a new method for the rapid determination of the moisture content in paper materials. The method is based on multiple headspace extraction gas chromatography (MHE-GC) at a temperature above the boiling point of water, from which an integrated water loss from the tested sample due to evaporation can be measured and from which the moisture content in the sample can be determined. The results show that the new method has a good precision (with the relative standard deviation <0.96%), high sensitivity (the limit of quantitation=0.005%) and good accuracy (the relative differences <1.4%). Therefore, the method is quite suitable for many uses in research and industrial applications.

  9. Hanford Tank Ventilation System Condensates and Headspace Vapors: An Assessment of Potential Dermal Exposures

    Energy Technology Data Exchange (ETDEWEB)

    Huckaby, James L.; Springer, David L.

    2006-04-24

    This study considers the question of whether potential dermal exposures to Hanford high-level radioactive waste tank headspace vapors and their condensates could result in significant exposure to workers. Three types of potential exposures were evaluated; dermal contact with aqueous condensate, organic condensate, and direct contact with head space vapors. The dermal absorption rates from aqueous and organic condensates were estimated for selected chemicals using a model described by EPA (1992) with a modified correlation for dermal permeability suggested by Wilschut et al. (1995). Dermal absorption rates of vapors were estimated using a model given by AIHA (2000). Results were compared to an ''equivalent inhalation dose'' calculated by multiplying the inhalation occupational exposure limit by a nominal daily inhalation rate. The results should provide guidance for industrial hygienists to prepare specific recommendations based on specific scenarios.

  10. Isolation and quantification of volatiles in fish by dynamic headspace sampling and mass spectrometry.

    Science.gov (United States)

    Refsgaard, H H; Haahr, A M; Jensen, B

    1999-03-01

    A dynamic headspace sampling method for isolation of volatiles in fish has been developed. The sample preparation involved freezing of fish tissue in liquid nitrogen, pulverizing the tissue, and sampling of volatiles from an aqueous slurry of the fish powder. Similar volatile patterns were determined by use of this sample preparation method and for samples chewed for 10 s. Effects of sampling time, temperature, and purge flow on level of volatiles were tested. Purging at 340 mL/min for 30 min at 45 degrees C was found to be optimal. Detection limits for a number of aldehydes were 0.2-2.7 microg/kg. Levels of volatiles are given for fresh salmon, cod, saithe, mackerel, and redfish.

  11. Floral scent of brazilian Passiflora: five species analised by dynamic headspace.

    Science.gov (United States)

    Montero, Daniel A V; Marques, Marcia Ortiz M; Meletti, Laura M M; Kampen, Maria H VAN; Polozzi, Sandra C

    2016-09-01

    This study describes for the first time the chemical composition and olfactive description of floral scent from Brazilian Passiflora (Passiflora edulis Sim, Passiflora alata Curtis, Passiflora cincinnata Mast., Passiflora coccinea Aubl. and Passiflora quadrangularis L.). Five species were grown in greenhouse at the Agronomic Institute (IAC), São Paulo, Brazil. Volatile compounds were collected using dynamic headspace. Analyses of scent composition were performed by gas chromatograph coupled to mass spectrometer. Identification of chemical constituents was conducted through of retention index followed by comparative analysis of mass spectra with specialized databases. The olfactive descriptions of floral scent from each species was evaluated for a professional perfumer. High interspecific diversity was found between chemical compositions of floral scent within Passiflora and different bouquets were observed amount the studied species. Mayor constituents were linalool (P. alata), geraniol (P. quadrangularis), 1,4-dimethoxybenzene (P. edulis), benzaldehyde (P. cincinnata) and 2-methyl-3-pentanone (P. coccinea).

  12. Floral scent of brazilian Passiflora: five species analised by dynamic headspace

    Directory of Open Access Journals (Sweden)

    DANIEL A.V. MONTERO

    2016-01-01

    Full Text Available ABSTRACT This study describes for the first time the chemical composition and olfactive description of floral scent from Brazilian Passiflora (Passiflora edulis Sim, Passiflora alata Curtis, Passiflora cincinnata Mast., Passiflora coccinea Aubl. and Passiflora quadrangularis L.. Five species were grown in greenhouse at the Agronomic Institute (IAC, São Paulo, Brazil. Volatile compounds were collected using dynamic headspace. Analyses of scent composition were performed by gas chromatograph coupled to mass spectrometer. Identification of chemical constituents was conducted through of retention index followed by comparative analysis of mass spectra with specialized databases. The olfactive descriptions of floral scent from each species was evaluated for a professional perfumer. High interspecific diversity was found between chemical compositions of floral scent within Passiflora and different bouquets were observed amount the studied species. Mayor constituents were linalool (P. alata, geraniol (P. quadrangularis, 1,4-dimethoxybenzene (P. edulis, benzaldehyde (P. cincinnata and 2-methyl-3-pentanone (P. coccinea.

  13. Headspace Solid Phase Micro Extraction Gas Chromatographic Determination of Fenthion in Human Serum

    Directory of Open Access Journals (Sweden)

    Kyriaki Machera

    2008-05-01

    Full Text Available A simple and effective analytical procedure was developed for the determination of fenthion residues in human serum samples. The sample treatment was performed using the headspace solid-phase micro extraction with polyacrylate fiber, which has the advantage to require low amount of serum (1 mL without tedious pre-treatment. The quantification of fenthion was carried out by gas chromatography-mass spectrometry and the recoveries ranged from 79 to 104% at two spiking levels for 6 replicates. Detection and quantification limits were calculated as 1.51 and 4.54 ng/mL of serum respectively. Two fenthion metabolites − fenoxon and fenthion–sulfoxide − were also identified.

  14. [Rapid determination of ethephon residues in concentrated pineapple juice by head-space gas chromatography].

    Science.gov (United States)

    Chu, X G; Yong, W; Cai, H X; Pan, J W

    2001-05-01

    The method developed is based on the special property that ethephon can be easily decomposed into ethene in alkaline solution by heating. Certain amount of concentrated KOH solution was added to the sample and heated at 70 degrees C. Then, 1 mL of the gas above the sample was injected into a gas chromatograph by head-space sampler for the determination of the target compound with external standard quantitation method. The detection limit was 0.025 mg/kg and the fortified recoveries of ethephon in concentrated pineapple juice (60 +/- 1) Brix at the range of 0.1 mg/kg-10 mg/kg were 92%-98% (n = 8, for each level). The relative standard deviations were 3.99%-7.94%.

  15. Identification and Characterization of Hydrogeologic Units at the Nevada Test Site Using Geophysical Logs: Examples from the Underground Test Area Project

    Energy Technology Data Exchange (ETDEWEB)

    Prothro, Lance [National Security Technologies, LLC, Las Vegas, NV (United States); Drellack, Sigmund [National Security Technologies, LLC, Las Vegas, NV (United States); Townsend, Margaret [National Security Technologies, LLC, Las Vegas, NV (United States)

    2009-03-25

    The diverse and complex geology of the Nevada Test Site region makes for a challenging environment for identifying and characterizing hydrogeologic units penetrated by wells drilled for the U.S. Department of Energy, National Nuclear Security Administration, Underground Test Area (UGTA) Environmental Restoration Sub-Project. Fortunately, UGTA geoscientists have access to large and robust sets of subsurface geologic data, as well as a large historical knowledge base of subsurface geological analyses acquired mainly during the underground nuclear weapons testing program. Of particular importance to the accurate identification and characterization of hydrogeologic units in UGTA boreholes are the data and interpretation principles associated with geophysical well logs. Although most UGTA participants and stakeholders are probably familiar with drill hole data such as drill core and cuttings, they may be less familiar with the use of geophysical logs; this document is meant to serve as a primer on the use of geophysical logs in the UGTA project. Standard geophysical logging tools used in the UGTA project to identify and characterize hydrogeologic units are described, and basic interpretation principles and techniques are explained. Numerous examples of geophysical log data from a variety of hydrogeologic units encountered in UGTA wells are presented to highlight the use and value of geophysical logs in the accurate hydrogeologic characterization of UGTA wells.

  16. Influence of olive oil phenolic compounds on headspace aroma release by interaction with whey proteins.

    Science.gov (United States)

    Genovese, Alessandro; Caporaso, Nicola; De Luca, Lucia; Paduano, Antonello; Sacchi, Raffaele

    2015-04-22

    The release of volatile compounds in an oil-in-water model system obtained from olive oil-whey protein (WP) pairing was investigated by considering the effect of phenolic compounds. Human saliva was used to simulate mouth conditions by retronasal aroma simulator (RAS) analysis. Twelve aroma compounds were quantified in the dynamic headspace by SPME-GC/MS. The results showed significant influences of saliva on the aroma release of virgin olive oil (VOO) volatiles also in the presence of WP. The interaction between WP and saliva leads to lower headspace release of ethyl esters and hexanal. Salivary components caused lower decrease of the release of acetates and alcohols. A lower release of volatile compounds was found in the RAS essay in comparison to that in orthonasal simulation of only refined olive oil (without addition of saliva or WP), with the exception of hexanal and 1-penten-3-one, where a significantly higher release was found. Our results suggest that the extent of retronasal odor (green, pungent) of these two volatile compounds is higher than orthonasal odor. An extra VOO was used to verify the release in model systems, indicating that WP affected aroma release more than model systems, while saliva seems to exert an opposite trend. A significant increase in aroma release was found when phenolic compounds were added to the system, probably due to the contrasting effects of binding of volatile compounds caused by WP, for the polyphenol-protein interaction phenomenon. Our study could be applied to the formulation of new functional foods to enhance flavor release and modulate the presence and concentrations of phenolics and whey proteins in food emulsions/dispersions.

  17. Systematic comparison of static and dynamic headspace sampling techniques for gas chromatography.

    Science.gov (United States)

    Kremser, Andreas; Jochmann, Maik A; Schmidt, Torsten C

    2016-09-01

    Six automated, headspace-based sample preparation techniques were used to extract volatile analytes from water with the goal of establishing a systematic comparison between commonly available instrumental alternatives. To that end, these six techniques were used in conjunction with the same gas chromatography instrument for analysis of a common set of volatile organic carbon (VOC) analytes. The methods were thereby divided into three classes: static sampling (by syringe or loop), static enrichment (SPME and PAL SPME Arrow), and dynamic enrichment (ITEX and trap sampling). For PAL SPME Arrow, different sorption phase materials were also included in the evaluation. To enable an effective comparison, method detection limits (MDLs), relative standard deviations (RSDs), and extraction yields were determined and are discussed for all techniques. While static sampling techniques exhibited sufficient extraction yields (approx. 10-20 %) to be reliably used down to approx. 100 ng L(-1), enrichment techniques displayed extraction yields of up to 80 %, resulting in MDLs down to the picogram per liter range. RSDs for all techniques were below 27 %. The choice on one of the different instrumental modes of operation (aforementioned classes) was thereby the most influential parameter in terms of extraction yields and MDLs. Individual methods inside each class showed smaller deviations, and the least influences were observed when evaluating different sorption phase materials for the individual enrichment techniques. The option of selecting specialized sorption phase materials may, however, be more important when analyzing analytes with different properties such as high polarity or the capability of specific molecular interactions. Graphical Abstract PAL SPME Arrow during the extraction of volatile analytes from the headspace of an aqueous sample.

  18. Analysis of ultrafine TATB by ultrasonic-assisted equilibrium headspace analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, D M

    2000-09-12

    The purpose of this work was to screen different lots of ultrafine 1,3,5-triamine 2,4,6-trinitrobenzene (TATB) for chemical differences, which may include synthesis and formulation byproducts, decomposition products, and contaminants. The approach used here permits analysis of trapped species as volatile and semivolatile chemicals within a solid. This procedure involves preconcentration of species from the TATB matrix into a surrounding headspace followed by a preconcentration and collection step using solid phase microextraction (SPME) collection. The sample is prepared by sealing it in a glass ampule with a few milliliters of water, ultrasonicating the solution, and then sampling the headspace using SPME collection. Water couples in the ultrasonic energy to fracture the TATB, which permits the release of nonpolar species into the gas phase. However, polar species will favor the aqueous phase and require a separate analysis procedure, which is not included here. Following SPME collection, the sample is transferred to a gas chromatography/mass spectrometer (GCMS) for analysis. In this work, we analyzed and interpreted outgas signatures from four different lots (1169-135MPS-001, 4271-135M-002, 91190-135M-003, and 98170-135M-001) of ultrafine TATB. Lot 98170-135M-001 is a reprocessing of Lot 4271-135M-002, which was washed to remove the water-soluble polysaccharides. The pedigree for these materials are found in a memo from Tom Stallings and Gordon Osborn of Mason & Hanger Co., Pantex Plant in the Appendix section. Nominally, ultrafine TATB is synthesized via the emulsion-amination method in which an emulsifier is included during the amination of the 1,3,5-trichloro-2,4,6-trinitrobenzene (TCTNB) precursor. The ultrafine TATB formulation also includes 0.2% by weight guar gum, a galactomannan polysaccharide, to enhance flow properties. Historically, this polysaccharide was added to PETN to reduce its sublimation temperature, but it was also found to enhance flow

  19. Bibliography of publications related to the Yucca Mountain Site Characterization Project prepared by U.S. Geological Survey personnel through April 1991

    Energy Technology Data Exchange (ETDEWEB)

    Glanzman, V.M.

    1991-11-01

    Personnel of the US Geological Survey have participated in nuclear-waste management studies in the State of Nevada since the mid-1970`s. A bibliography of publications prepared principally for the US Department of Energy Yucca Mountain Site Characterization Project (formerly Nevada Nuclear Waste Storage Investigations) through April 1991 contains 475 entries in alphabetical order. The listing includes publications prepared prior to the inception of the Nevada Nuclear Waste Storage Investigations Project in April 1977 and selected publications of interest to the Yucca Mountain region. 480 refs.

  20. Sequencing and characterizing the genome of Estrella lausannensis as an undergraduate project: training students and biological insights.

    Science.gov (United States)

    Bertelli, Claire; Aeby, Sébastien; Chassot, Bérénice; Clulow, James; Hilfiker, Olivier; Rappo, Samuel; Ritzmann, Sébastien; Schumacher, Paolo; Terrettaz, Céline; Benaglio, Paola; Falquet, Laurent; Farinelli, Laurent; Gharib, Walid H; Goesmann, Alexander; Harshman, Keith; Linke, Burkhard; Miyazaki, Ryo; Rivolta, Carlo; Robinson-Rechavi, Marc; van der Meer, Jan Roelof; Greub, Gilbert

    2015-01-01

    With the widespread availability of high-throughput sequencing technologies, sequencing projects have become pervasive in the molecular life sciences. The huge bulk of data generated daily must be analyzed further by biologists with skills in bioinformatics and by "embedded bioinformaticians," i.e., bioinformaticians integrated in wet lab research groups. Thus, students interested in molecular life sciences must be trained in the main steps of genomics: sequencing, assembly, annotation and analysis. To reach that goal, a practical course has been set up for master students at the University of Lausanne: the "Sequence a genome" class. At the beginning of the academic year, a few bacterial species whose genome is unknown are provided to the students, who sequence and assemble the genome(s) and perform manual annotation. Here, we report the progress of the first class from September 2010 to June 2011 and the results obtained by seven master students who specifically assembled and annotated the genome of Estrella lausannensis, an obligate intracellular bacterium related to Chlamydia. The draft genome of Estrella is composed of 29 scaffolds encompassing 2,819,825 bp that encode for 2233 putative proteins. Estrella also possesses a 9136 bp plasmid that encodes for 14 genes, among which we found an integrase and a toxin/antitoxin module. Like all other members of the Chlamydiales order, Estrella possesses a highly conserved type III secretion system, considered as a key virulence factor. The annotation of the Estrella genome also allowed the characterization of the metabolic abilities of this strictly intracellular bacterium. Altogether, the students provided the scientific community with the Estrella genome sequence and a preliminary understanding of the biology of this recently-discovered bacterial genus, while learning to use cutting-edge technologies for sequencing and to perform bioinformatics analyses.

  1. Volatile profile of the headspace fraction of "assa-peixe" (Vernonia sp. honeys Perfil dos compostos voláteis presentes na fração "headspace" de méis de assa-peixe

    Directory of Open Access Journals (Sweden)

    Mariana Carvalho Ribeiro

    2008-03-01

    Full Text Available The volatile compounds were isolated from the headspace fraction of "assa-peixe" honeys by adsorptive column chromatography, eluted with acetone and analysed by GC-FID and GC-MS. Volatile compounds were separated using a polar phase column. Low- and medium-boiling point volatile compounds predominated in the headspace. A large proportion of 3-penten-2-one (80.5 ± 13.9 µg.kg-1 and benzaldehyde (25.9 ± 4.2 µg.kg-1 was found in the headspace fraction, while 2-penten-1-ol, 3-hexenyl butanoate, octadecane and hexanoic acid (Os compostos voláteis da fração "Headspace" de méis de assa-peixe foram adsorvidos pela técnica de cromatografia de adsorção, eluídos com acetona e analisados através da CG/DIC e CG/EM usando coluna polar de sílica fundida. Os compostos voláteis de baixo e médio ponto de ebulição predominaram na fração "headspace". Foi achada uma grande proporção de 3-penten-2-ona (80,5 ± 13,9 µg.kg-1 e benzaldeído (25,9 ± 4,2 µg.kg-1, enquanto o 2-penten-1-ol, o hexanoato de 3-hexenila, o octadecano e o ácido hexanóico (<0,01 µg.kg-1 foram compostos minoritários. Um total de doze compostos voláteis foi identificado, sendo cinco descritos pela primeira vez no mel de assa-peixe. Destes cinco, a 3-penten-2-ona, o dodecano, o tridecano e o benzaldeído foram definitivamente identificados na fração "headspace" dos méis de assa-peixe brasileiro.

  2. Neurochemical, morphologic, and laminar characterization of cortical projection neurons in the cingulate motor areas of the macaque monkey

    Science.gov (United States)

    Nimchinsky, E. A.; Hof, P. R.; Young, W. G.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1996-01-01

    The primate cingulate gyrus contains multiple cortical areas that can be distinguished by several neurochemical features, including the distribution of neurofilament protein-enriched pyramidal neurons. In addition, connectivity and functional properties indicate that there are multiple motor areas in the cortex lining the cingulate sulcus. These motor areas were targeted for analysis of potential interactions among regional specialization, connectivity, and cellular characteristics such as neurochemical profile and morphology. Specifically, intracortical injections of retrogradely transported dyes and intracellular injection were combined with immunocytochemistry to investigate neurons projecting from the cingulate motor areas to the putative forelimb region of the primary motor cortex, area M1. Two separate groups of neurons projecting to area M1 emanated from the cingulate sulcus, one anterior and one posterior, both of which furnished commissural and ipsilateral connections with area M1. The primary difference between the two populations was laminar origin, with the anterior projection originating largely in deep layers, and the posterior projection taking origin equally in superficial and deep layers. With regard to cellular morphology, the anterior projection exhibited more morphologic diversity than the posterior projection. Commissural projections from both anterior and posterior fields originated largely in layer VI. Neurofilament protein distribution was a reliable tool for localizing the two projections and for discriminating between them. Comparable proportions of the two sets of projection neurons contained neurofilament protein, although the density and distribution of the total population of neurofilament protein-enriched neurons was very different in the two subareas of origin. Within a projection, the participating neurons exhibited a high degree of morphologic heterogeneity, and no correlation was observed between somatodendritic morphology and

  3. Annual report on the Background Soil Characterization Project on the Oak Ridge Reservation, Oak Ridge, Tennessee: Results of Phase 1 investigation

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, D.R.; Goddard, P.L.; Hatmaker, T.L.; Hook, L.A.; Jackson, B.L.; Kimbrough, C.W.; Lee, S.Y.; Lietzke, D.A.; McGin, C.W.; Nourse, B.D.; Schmoyer, R.L.; Shaw, R.A.; Stinnette, S.E.; Switek, J.; Wright, J.C. [Oak Ridge National Lab., TN (United States); Ammons, J.T.; Branson, J.L.; Burgoa, B.B. [Tennessee Univ., Knoxville, TN (United States). Dept. of Plant and Soil Science; Lietzke, D.A. [Lietzke (David A.), Rutledge, TN (United States)

    1993-05-01

    Many constituents of potential concern for human health occur naturally at low concentrations in undisturbed soils. The Background soil Characterization Project (BSCP) was undertaken to provide background concentration data on potential contaminants in natural soils on the Oak Ridge Reservation (ORR). The objectives of the BSCP are to provide baseline data for contaminated site assessment and estimates of potential human health risk associated with background concentrations of hazardous and other constituents in native soils. This report presents, evaluates, and documents data and results obtained in Phase I of the project. It is intended to be a stand-alone document for application and use in structuring and conducting remedial investigation and remedial action projects in the Environmental Restoration (ER) Program.

  4. Simultaneous Determination of Methanol, Ethanol and Formic Acid in Serum and Urine by Headspace GC-FID.

    Science.gov (United States)

    Bursová, Miroslava; Hložek, Tomáš; Čabala, Radomír

    2015-01-01

    A simple, cost-effective headspace gas chromatography (GC) method coupled with GC with flame ionization detection for simultaneous determination of methanol, ethanol and formic acid was developed and validated for clinical and toxicological purposes. Formic acid was derivatized with an excess of isopropanol under acidic conditions to its volatile isopropyl ester while methanol and ethanol remained unchanged. The entire sample preparation procedure is complete within 6 min. The design of the experiment (the face-centered central composite design) was used for finding the optimal conditions for derivatization, headspace sampling and chromatographic separation. The calibration dependences of the method were quadratic in the range from 50 to 5,000 mg/L, with adequate accuracy (89.0-114.4%) and precision (<12%) in the serum. The new method was successfully used for determination of selected analytes in serum samples of intoxicated patients from among those affected by massive methanol poisonings in the Czech Republic in 2012.

  5. Aroma compound analysis of Eruca sativa (Brassicaceae) SPME headspace leaf samples using GC, GC-MS, and olfactometry.

    Science.gov (United States)

    Jirovetz, Leopold; Smith, David; Buchbauer, Gerhard

    2002-07-31

    The aroma compounds of rocket salad (Eruca sativa) SPME headspace samples of fresh leaves were analyzed using GC, GC-MS, and olfactometry. More than 50 constituents of the Eruca headspace could be identified to be essential volatiles, responsible for the characteristic intense green; herbal; nutty and almond-like; Brassicaceae-like (direction of cabbage, broccoli, and mustard); and horseradish-like aroma of these salad leaves. As aroma impact compounds, especially isothiocyanates, and derivatives of butane, hexane, octane, and nonane were identified. 4-Methylthiobutyl isothiocyanate (14.2%), cis-3-hexen-1-ol (11.0%), cis-3-hexenyl butanoate (10.8%), 5-methylthiopentyl isothiocyanate (9.3%), cis-3-hexenyl 2-methylbutanoate (5.4%), and 5-methylthiopentanenitrile (5.0%) were found in concentrations higher than 5.0% (calculated as % peak area of GC analysis using a nonpolar column).

  6. Understanding the role of saliva in aroma release from wine by using static and dynamic headspace conditions.

    Science.gov (United States)

    Muñoz-González, Carolina; Feron, Gilles; Guichard, Elisabeth; Rodríguez-Bencomo, J José; Martín-Álvarez, Pedro J; Moreno-Arribas, M Victoria; Pozo-Bayón, M Ángeles

    2014-08-20

    The aim of this work was to determine the role of saliva in wine aroma release by using static and dynamic headspace conditions. In the latter conditions, two different sampling points (t = 0 and t = 10 min) corresponding with oral (25.5 °C) and postoral phases (36 °C) were monitored. Both methodologies were applied to reconstituted dearomatized white and red wines with different nonvolatile wine matrix compositions and a synthetic wine (without matrix effect). All of the wines had the same ethanol concentration and were spiked with a mixture of 45 aroma compounds covering a wide range of physicochemical characteristics at typical wine concentrations. Two types of saliva (human and artificial) or control samples (water) were added to the wines. The adequacy of the two headspace methodologies for the purposes of the study (repeatability, linear ranges, determination coefficients, etc.) was previously determined. After application of different chemometric analysis (ANOVA, LSD, PCA), results showed a significant effect of saliva on aroma release dependent on saliva type (differences between artificial and human) and on wine matrix using static headspace conditions. Red wines were more affected than white and synthetic wines by saliva, specifically human saliva, which provoked a reduction in aroma release for most of the assayed aroma compounds independent of their chemical structure. The application of dynamic headspace conditions using a saliva bioreactor at the two different sampling points (t = 0 and t = 10 min) showed a lesser but significant effect of saliva than matrix composition and a high influence of temperature (oral and postoral phases) on aroma release.

  7. "Aqua-space", a new headspace method for isolation of natural floral aromas using humidified air as a carrier gas.

    Science.gov (United States)

    Ishikawa, Masashi; Honda, Tsutomu; Fujita, Akira; Kurobayashi, Yoshiko; Kitahara, Takeshi

    2004-02-01

    A new method called "Aqua-space" was developed for the isolation of the natural fragrances of plants. Living flowers were enclosed in a space under simulated natural conditions, and humidified air was pumped into the space as a fragrance carrier. In a comparison among three isolation methods, i.e., Aqua-space, headspace, and solvent extraction, the Aqua-space method proved to be the most effective in retaining natural fragrances with abundant oxygenated components key to floral fragrances.

  8. Rapid Separation of Elemental Species by Fast Multicapillary Gas Chromatography with Multichannel Optical Spectrometry Detection following Headspace Solid Phase Microextraction

    OpenAIRE

    Jacek Giersz; Krzysztof Jankowski; Monika Truskolaska

    2015-01-01

    A method for conducting fast and efficient gas chromatography based on short multicapillaries in straight alignment combined with atomic emission detection was developed for field analysis. The strategy enables for speciation analysis of organometallic compounds. The analytes are simultaneously ethylated and preconcentrated on a solid phase microextraction (SPME) fiber placed in the headspace over the sample for 25 min. The ethylated species are then completely separated and selectively quant...

  9. New cold-fiber headspace solid-phase microextraction device for quantitative extraction of polycyclic aromatic hydrocarbons in sediment.

    Science.gov (United States)

    Ghiasvand, Ali Reza; Hosseinzadeh, Shokouh; Pawliszyn, Janusz

    2006-08-18

    A new automated headspace solid-phase microextraction (HS-SPME) sampling device was developed, with the capability of heating the sample matrix and simultaneously cooling the fiber coating. The device was evaluated for the quantitative extraction of polycyclic aromatic hydrocarbons (PAHs) from solid matrices. The proposed device improves the efficiency of the release of analytes from the matrix, facilitates the mass transfer into the headspace and significantly increases the partition coefficients of the analytes, by creating a temperature gap between the cold-fiber (CF) coating and the hot headspace. The reliability and applicability of previously reported cold-fiber devices are significantly enhanced by this improvement. In addition, it can be easily adopted for full automation of extraction, enrichment and introduction of different samples using commercially available autosampling devices. Sand samples spiked with PAHs were used as solid matrices and the effect of different experimental parameters were studied, including the extraction temperature, extraction time, moisture content, and the effect of sonication and modifier under optimal experimental conditions, linear calibration curves were obtained in the range of 0.0009-1000 ng/g, with regression coefficients higher than 0.99 and detection limits that ranged from 0.3 to 3 pg/g. Reproducible, precise and high throughput extraction, monitoring and quantification of PAHs were achieved with the automated cold-fiber headspace solid-phase microextraction (CF-HS-SPME) device coupled to GC-flame ionization detection. Determination of PAHs in certified reference sediments using the proposed approach exhibited acceptable agreement with the standard values.

  10. Application of headspace solid phase microextraction for study of noncovalent interaction of borneol with human serum albumin

    Institute of Scientific and Technical Information of China (English)

    Liang HU; Dong-ying CHEN

    2009-01-01

    Aim: To investigate noncovalent interactions between borneol and human serum albumin (HSA) under near-physiological conditions. Methods: A 65-um polydimethylsiloxane (PDMS) fiber was selected for sampling. The extraction temperature was kept at 37 ℃, and the extraction time was optimized at 10 min. Borneol solutions of different concentrations were equilibrated in 600 umol/L HSA and 67 mmol/L phosphate buffer solution (pH 7.4,37 ℃) for 24 h prior to solid phase microextraction (SPME) using headspace mode. The binding properties were obtained based on the calculation of extracted borneol amount using gas chromatography (GC) determination. Results: The headspace SPME extraction method avoided disturbance from the HSA binding matrix. The recovery showed good linearity for the borneol concentrations over the range of 0.4-16.3 μmol/L with a regression coefficient (R~2) of 0.9998. The limit of detection and lower limit of quantitation were determined to be 0.01 umol/L and 0.4 umol/L, respectively. The binding constant and the percentage binding rate were estimated to be 2.4×10~3(mol/L)~(-1) and 59.5%, respectively.Conclusion: Headspace SPME coupled to GC is a simple, sensitive and rapid method for the study of borneol binding to HSA. The method may be applied in the determination of other protein binding properties in human plasma.

  11. Full evaporation headspace gas chromatography for sensitive determination of high boiling point volatile organic compounds in low boiling matrices.

    Science.gov (United States)

    Mana Kialengila, Didi; Wolfs, Kris; Bugalama, John; Van Schepdael, Ann; Adams, Erwin

    2013-11-08

    Determination of volatile organic components (VOC's) is often done by static headspace gas chromatography as this technique is very robust and combines easy sample preparation with good selectivity and low detection limits. This technique is used nowadays in different applications which have in common that they have a dirty matrix which would be problematic in direct injection approaches. Headspace by nature favors the most volatile compounds, avoiding the less volatile to reach the injector and column. As a consequence, determination of a high boiling solvent in a lower boiling matrix becomes challenging. Determination of VOCs like: xylenes, cumene, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMA), N-methyl-2-pyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI), benzyl alcohol (BA) and anisole in water or water soluble products are an interesting example of the arising problems. In this work, a headspace variant called full evaporation technique is worked out and validated for the mentioned solvents. Detection limits below 0.1 μg/vial are reached with RSD values below 10%. Mean recovery values ranged from 92.5 to 110%. The optimized method was applied to determine residual DMSO in a water based cell culture and DMSO and DMA in tetracycline hydrochloride (a water soluble sample). Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Analysis of volatile organic compounds emitted from aircraft carpets:comparison using headspace and dynamic chamber tests 

    Institute of Scientific and Technical Information of China (English)

    WANG Chao; YANG Xu-Dong; GAO Peng

    2014-01-01

    Volatile organic compounds (VOCs) emitted from three types of carpets used in aircrafts were compared by using headspace and dynamic chamber tests. The headspace samples contained many compounds that were not detected in the dynamic chamber test;in addition, the dominant VOCs found by these two methods were different. The findings indicate that for highly sorptive materials such as carpets, headspace analysis may give inaccurate indication of actual VOC emissions, and it is necessary to conduct dynamic chamber tests over a certain period of time in order to identify the true emission characteristics. From the dynamic chamber tests, 2-ethyl-1-hexanol was the main VOC emitted from all three carpets. The study also examined the emission characteristics of aircraft carpets. In all experiments, total VOC (TVOC) concentration peaked within a few hours after the start of the experiment and was followed by rapid decay. The emission parameters of TVOC emitted by all three carpets were calculated and the simulated data matched the measured data well.

  13. [Determination of partition coefficient of dissolved gases in transformer oil using phase ratio variation method and static headspace gas chromatography].

    Science.gov (United States)

    Zhao, Jinghong; Wang, Hailong; Liu, Wenmin; Zhou, Yansheng; Guan, Yafeng

    2004-05-01

    The partition coefficients of dissolved gases in transformer oil were determined using a phase ratio variation method and static headspace gas chromatography (GC). A pressure balancing and gas volume-metering device was connected to the vent of a sample loop on a six-port injection valve of the GC. The gas phase sample from the headspace vial of 25 mL was transferred to an 80 microL sample-loop through a fused silica capillary of 0.53 mm i.d., and then separated and determined quantitatively by GC. A 2 m x 1 mm i.d. GDX502 micro-packed column was used for the separation. Five different gas-liquid volume ratios in the headspace vials were measured at different equilibrium concentrations. The partition coefficients of hydrocarbon gases including methane, acetylene, ethylene, ethane and propane dissolved in transformer oil were determined by using linear regression analysis at 20 degrees C and 50 degrees C separately. The errors between the real values and regression values from experimental data were less than 4.14% except methane. Fundamental data for on-line measurement of dissolved gases in transformer oil are provided by GC.

  14. Novel multiwalled carbon nanotubes-polyaniline composite film coated platinum wire for headspace solid-phase microextraction and gas chromatographic determination of phenolic compounds.

    Science.gov (United States)

    Du, Wei; Zhao, Faqiong; Zeng, Baizhao

    2009-05-01

    A novel multiwalled carbon nanotubes-polyaniline composite (MWCNTs-PANI) film coated platinum wire was fabricated through electrochemical deposition. The coating was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectrophotometry and thermogravimetry. It was found that the coating was porous and had large specific area and adsorption capacity; in the composite MWCNTs and polyaniline interacted with each other and the film kept stable up to 320 degrees C. The as-made fiber was used for the headspace solid-phase microextraction (HS-SPME) of some phenolic compounds (i.e. 2-chlorophenol, 2,4-dichlorophenol, 2-methylphenol, 3-methylphenol, 2,6-dimethylphenol, 2-nitrophenol), followed by gas chromatographic analysis. The MWCNTs-PANI coating showed better analytical performance than PANI. Under the optimized conditions, the detection limits were 1.89-65.9 ng L(-1), the relative standard deviations (RSDs) were 2.7-6.5% for six successive measurements with single fiber, the RSDs for fiber-to-fiber were 5.2-12.4%, the linear ranges exceeded two magnitudes with correlation coefficient above 0.992. The fiber could be used for more than 250 times without decrease of efficiency. The proposed method was successfully applied to the extraction and determination of phenolic compounds in water sample, and the recoveries were 87.7-111.5% for different analytes. In addition, the fiber also presented advantages of easy preparation and low cost. Therefore, it is a promising SPME fiber.

  15. Graphene oxide based sol-gel stainless steel fiber for the headspace solid-phase microextraction of organophosphate ester flame retardants in water samples.

    Science.gov (United States)

    Jin, Tingting; Cheng, Jing; Cai, Cuicui; Cheng, Min; Wu, Shiju; Zhou, Hongbin

    2016-07-29

    In this paper, graphene oxide was coated onto a stainless steel wire through sol-gel technique and it was used as a solid phase microextraction (SPME) fiber. The prepared fiber was characterized by scanning electron microscopy (SEM), which displayed that the fiber had crinkled surface and porous structure The application of the fiber was evaluated through the headspace SPME of nine organophosphate ester flame retardants (OPFRs) with different characteristics in water samples followed by gas chromatography and nitrogen-phosphorous detector (GC/NPD). The major factors influencing the extraction efficiency, including the extraction and desorption conditions, were studied and optimized. Under the optimum conditions, the proposed method was evaluated, and applied to the analysis of organophosphate ester flame retardants in real environmental water samples. The results demonstrated the HS-SPME method based on GO sol-gel fiber had good linearity (R>0.9928), and limits of detection (1.4-135.6ngL(-1)), high repeatability (RSDsol-gel fiber displayed bigger extraction capability than the commercial PDMS fiber and the pure sol-gel fiber for both polar and apolar organophosphate esters, especially for the OPFRs containing benzene rings.

  16. Headspace-Solid-Phase Microextraction-Gas Chromatography as Analytical Methodology for the Determination of Volatiles in Wild Mushrooms and Evaluation of Modifications Occurring during Storage

    Directory of Open Access Journals (Sweden)

    Rosaria Costa

    2015-01-01

    Full Text Available Mushrooms are sources of food, medicines, and agricultural means. Not much is reported in the literature about wild species of the Mediterranean flora, although many of them are traditionally collected for human consumption. The knowledge of their chemical constituents could represent a valid tool for both taxonomic and physiological characterizations. In this work, a headspace-solid-phase microextraction (HS-SPME method coupled with GC-MS and GC-FID was developed to evaluate the volatile profiles of ten wild mushroom species collected in South Italy. In addition, in order to evaluate the potential of this analytical methodology for true quantitation of volatiles, samples of the cultivated species Agaricus bisporus were analyzed. The choice of this mushroom was dictated by its ease of availability in the food market, due to the consistent amounts required for SPME method development. For calibration of the main volatile compounds, the standard addition method was chosen. Finally, the assessed volatile composition of A. bisporus was monitored in order to evaluate compositional changes occurring during storage, which represents a relevant issue for such a wide consumption edible product.

  17. Polydopamine-based immobilization of a hydrazone covalent organic framework for headspace solid-phase microextraction of pyrethroids in vegetables and fruits.

    Science.gov (United States)

    Wu, Mingxue; Chen, Gang; Liu, Ping; Zhou, Weihong; Jia, Qiong

    2016-07-22

    We designed a novel hydrazone covalent organic framework (COF) and developed a polydopamine (PDA) method to immobilize COF on a stainless steel fiber for headspace solid-phase microextraction (HS-SPME). A series of characterization studies was performed to validate the structure and property of the prepared fiber. The COF-PDA fiber was applied for the extraction of pyrethroids coupled with gas chromatography equipped with an electron capture detector (GC-ECD). Under the optimum experimental conditions, high enhancement factors of 307-2327 were achieved, indicating that the hydrazone COF possessed good extraction efficiency for pyrethroids. The detection limits ranged from 0.11 to 0.23μgkg(-1) with relative standard deviations varying in the range of 3.6-9.2% (intra-batch) and 6.9-12.1% (inter-batch), respectively. The developed method was applied to the determination of pyrethroids in fruit and vegetable samples and the accuracy was assessed through recovery experiments. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. WIPP waste characterization program sampling and analysis guidance manual

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The Waste Isolation Pilot Plant (WIPP) Waste Characterization Program Sampling and Analysis Guidance Manual (Guidance Manual) provides a unified source of information on the sampling and analytical techniques that enable Department of Energy (DOE) facilities to comply with the requirements established in the current revision of the Quality Assurance Program Plan (QAPP) for the WIPP Experimental-Waste Characterization Program (the Program). This Guidance Manual includes all of the sampling and testing methodologies accepted by the WIPP Project Office (DOE/WPO) for use in implementing the Program requirements specified in the QAPP. This includes methods for characterizing representative samples of transuranic (TRU) wastes at DOE generator sites with respect to the gas generation controlling variables defined in the WIPP bin-scale and alcove test plans, as well as waste container headspace gas sampling and analytical procedures to support waste characterization requirements under the WIPP test program and the Resource Conservation and Recovery Act (RCRA). The procedures in this Guidance Manual are comprehensive and detailed and are designed to provide the necessary guidance for the preparation of site specific procedures. The use of these procedures is intended to provide the necessary sensitivity, specificity, precision, and comparability of analyses and test results. The solutions to achieving specific program objectives will depend upon facility constraints, compliance with DOE Orders and DOE facilities' operating contractor requirements, and the knowledge and experience of the TRU waste handlers and analysts. With some analytical methods, such as gas chromatography/mass spectrometry, the Guidance Manual procedures may be used directly. With other methods, such as nondestructive/destructive characterization, the Guidance Manual provides guidance rather than a step-by-step procedure.

  19. Class III Mid-Term Project, "Increasing Heavy Oil Reserves in the Wilmington Oil Field Through Advanced Reservoir Characterization and Thermal Production Technologies"

    Energy Technology Data Exchange (ETDEWEB)

    Scott Hara

    2007-03-31

    The overall objective of this project was to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involved improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective has been to transfer technology that can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The first budget period addressed several producibility problems in the Tar II-A and Tar V thermal recovery operations that are common in SBC reservoirs. A few of the advanced technologies developed include a three-dimensional (3-D) deterministic geologic model, a 3-D deterministic thermal reservoir simulation model to aid in reservoir management and subsequent post-steamflood development work, and a detailed study on the geochemical interactions between the steam and the formation rocks and fluids. State of the art operational work included drilling and performing a pilot steam injection and production project via four new horizontal wells (2 producers and 2 injectors), implementing a hot water alternating steam (WAS) drive pilot in the existing steamflood area to improve thermal efficiency, installing a 2400-foot insulated, subsurface harbor channel crossing to supply steam to an island location, testing a novel alkaline steam completion technique to control well sanding problems, and starting on an advanced reservoir management system through computer-aided access to production and geologic data to integrate reservoir characterization, engineering, monitoring, and evaluation. The second budget period phase (BP2) continued to implement state-of-the-art operational work to optimize thermal recovery processes, improve well drilling and completion practices, and evaluate the

  20. Analysis of endogenous aldehydes in human urine by static headspace gas chromatography-mass spectrometry.

    Science.gov (United States)

    Serrano, María; Gallego, Mercedes; Silva, Manuel

    2016-03-11

    Endogenous aldehydes (EAs) generated during oxidative stress and cell processes are associated with many pathogenic and toxicogenic processes. The aim of this research was to develop a solvent-free and automated analytical method for the determination of EAs in human urine using a static headspace generator sampler coupled with gas chromatography-mass spectrometry (HS-GC-MS). Twelve significant EAs used as markers of different biochemical and physiological processes, namely short- and medium-chain alkanals, α,β-unsaturated aldehydes and dicarbonyl aldehydes have been selected as target analytes. Human urine samples (no dilution is required) were derivatized with O-2,3,4,5,6-pentafluorobenzylhydroxylamine in alkaline medium (hydrogen carbonate-carbonate buffer, pH 10.3). The HS-GC-MS method developed renders an efficient tool for the sensitive and precise determination of EAs in human urine with limits of detection from 1 to 15ng/L and relative standard deviations, (RSDs) from 6.0 to 7.9%. Average recoveries by enriching urine samples ranged between 92 and 95%. Aldehydes were readily determined at 0.005-50μg/L levels in human urine from healthy subjects, smokers and diabetic adults.

  1. Determination of ethanol content in medicated syrups by static headspace gas chromatography.

    Science.gov (United States)

    Huzar, Elźbieta; Wodnicka, Alicja

    2013-01-01

    Liquid drug preparations are the most convenient for pediatric patients. Unfortunately, these formulations very often contain ethanol, which may have an impact on children development. Moreover, medicines containing alcohol may cause undesirable interactions in conjunction with other drugs. This work reports complete validated method for the quantitation of ethanol in commercial medicated syrups. For determination of ethanol headspace gas chromatography and different methods of quantitative analysis were used. The analyzed samples of commercial medicated syrups available on the home marked contained from 3.37 to 8.65% (v/v) of ethanol. The estimated theoretical values of blood ethanol concentration for children after single recommended dose ingestion were at least twice lower than 0.125 g/mL. The process of validation showed that the applied GC method is selective, sensitive, linear and precise. The use of internal standard makes it accurate. The developed method could be considered as an analytical tool for the quality control of various liquid drug preparations.

  2. Headspace in-tube microextraction coupled with micellar electrokinetic chromatography of neutral aromatic compounds.

    Science.gov (United States)

    Cho, Sung Min; Park, Bum Su; Jung, Woo Sung; Lee, Sang Won; Jung, Yunhwan; Chung, Doo Soo

    2016-02-01

    Headspace (HS) extraction can be carried out easily and aptly via single drop microextraction coupled with capillary electrophoresis (CE). However, one drawback is the difficulty of keeping the single drop stably at the capillary tip. To solve this problem, we have recently demonstrated HS in-tube microextraction (ITME) of acidic compounds such as chlrophenols in an acidic sample using a basic run buffer plug in the separation capillary for CE as an acceptor phase. In this report, an organic acceptor plug in a capillary was used to extract neutral organic volatile pollutants such as BTEX (benzene, toluene, ethylbenzene, and m-xylene). After extraction, the analytes enriched in the organic acceptor plug were analyzed with micellar electrokinetic chromatography (MEKC). The enrichment factors for BTEX in a standard solution were up to 350 under an optimal condition of 25°C for 20 min. As an application, BTEX spiked into bottled water were analyzed with HS-ITME-MEKC, and the enrichment factors for BTEX were up to 320. The limits of detections were 1-4 ppb, which are at least 200 times lower than the US Environmental Protection Agency guidelines for drinking water, except benzene. The entire procedure of HS-ITME-MEKC was carried out automatically using a commercial CE instrument.

  3. [Simultaneous determination of seven residual solvents in bovis calculus artifactus by headspace gas chromatography].

    Science.gov (United States)

    Chi, Shuyao; Wu, Dike; Sun, Jinhong; Ye, Ruhan; Wang, Xiaoyan

    2014-05-01

    A headspace gas chromatography (HS-GC) method was developed for the simultaneous determination of seven residual solvents (petroleum ether (60-90 degrees C), acetone, ethyl acetate, methanol, methylene chloride, ethanol and butyl acetate) in bovis calculus artifactus. The DB-WAX capillary column and flame ionization detector (FID) were used for the separation and detection of the residual solvents, and the internal standard method was used for the quantification. The chromatographic conditions, such as equilibrium temperature and equilibrium time, were optimized. Under the optimized conditions, all of the seven residual solvents showed good linear relationships with good correlation coefficients (not less than 0.999 3) in the prescribed concentration range. At three spiked levels, the recoveries for the seven residual solvents were 94.7%-105.2% with the relative standard deviations (RSDs) less than 3.5%. The limits of detection (LODs) of the method were 0.43-5.23 mg/L, and the limits of quantification (LOQs) were 1.25-16.67 mg/L. The method is simple, rapid, sensitive and accurate, and is suitable for the simultaneous determination of the seven residual solvents in bovis calculus artifactus.

  4. Determination of amphetamines in human urine by headspace solid-phase microextraction and gas chromatography.

    Science.gov (United States)

    Raikos, Nikolaos; Christopoulou, Klio; Theodoridis, Georgios; Tsoukali, Heleni; Psaroulis, Dimitrios

    2003-06-05

    Solid-phase microextraction (SPME) is under investigation for its usefulness in the determination of a widening variety of volatile and semivolatile analytes in biological fluids and materials. Semivolatiles are increasingly under study as analytical targets, and difficulties with small partition coefficients and long equilibration times have been identified. Amphetamines were selected as semivolatiles exhibiting these limitations and methods to optimize their determination were investigated. A 100- micro m polydimethylsiloxane (PDMS)-coated SPME fiber was used for the extraction of the amphetamines from human urine. Amphetamine determination was made using gas chromatography (GC) with flame-ionization detection (FID). Temperature, time and salt saturation were optimized to obtain consistent extraction. A simple procedure for the analysis of amphetamine (AMP) and methamphetamine (MA) in urine was developed and another for 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxy-N-methamphetamine (MDMA) and 3,4-methylenedioxy-N-ethylamphetamine (MDEA) using headspace solid-phase microextraction (HS-SPME) and GC-FID. Higher recoveries were obtained for amphetamine (19.5-47%) and methamphetamine (20-38.1%) than MDA (5.1-6.6%), MDMA (7-9.6%) and MDEA (5.4-9.6%).

  5. Selective fiber used for headspace solid-phase microextraction of abused drugs in human urine

    Directory of Open Access Journals (Sweden)

    Sunanta Wangkarn

    2007-09-01

    Full Text Available A sensitive and selective fiber for simultaneous analysis of three drugs of abuse (amphetamine, methamphetamine and ephedrine in urine samples was explored using headspace solid phase microextraction and gas chromatography with flame ionization detection. Several parameters affecting extraction such as extraction time, extraction temperature, pH of solution and salt concentrations were investigated. Among five commercially available fibers, divinylbenzene/carboxen/ polydimethylsiloxane is the most sensitive and selective fiber at pH 10.0, extraction temperature at 80 C for 20 min and desorption temperature at 220 C for 2 min. Under the optimal conditions, the proposed solid phase microextraction method provided good linearity in the ranges 0.1-10 µg/ml for amphetamine and methamphetamine and 0.5-20 µg/ml for ephedrine. The detection limits for amphetamine, methamphetamine and ephedrine were 9, 3 and 30 ng/ml, respectively. The recoveries of three drugs in urine samples were exceeding 85%.

  6. Headspace Analysis of Philippine Civet Coffee Beans Using Gas Chromatography-Mass Spectrometry and Electronic Nose

    Science.gov (United States)

    Ongo, E.; Sevilla, F.; Antonelli, A.; Sberveglieri, G.; Montevecchi, G.; Sberveglieri, V.; de Paola, E. L.; Concina, I.; Falasconi, M.

    2011-11-01

    Civet coffee, the most expensive and best coffee in the world, is an economically important export product of the Philippines. With a growing threat of food adulteration and counterfeiting, a need for quality authentication is essential to protect the integrity and strong market value of Philippine civet coffee. At present, there is no internationally accepted method of verifying whether a bean is an authentic civet coffee. This study presented a practical and promising approach to identify and establish the headspace qualitative profile of Philippine civet coffee using electronic nose (E-nose) and gas chromatography-mass spectrometry (GC-MS). E-nose analysis revealed that aroma characteristic is one of the most important quality indicators of civet coffee. The findings were supported by GC-MS analysis. Principal component analysis (PCA) exhibited a clearly separated civet coffees from their control beans. The chromatographic fingerprints indicated that civet coffees differed with their control beans in terms of composition and concentration of individual volatile constituents.

  7. Headspace Solid-Phase Microextraction Analysis of Volatile Components in Narcissus tazetta var. chinensis Roem

    Directory of Open Access Journals (Sweden)

    Hai-Shan Chi

    2013-11-01

    Full Text Available The volatile components in single-flowered and double-flowered Chinese narcissus were identified by headspace-solid phase microextraction (HS-SPME coupled with GC and GC/MS. Changes in aroma during the vase-life (days 0, 1, 2, 3, 4, 5 and 6 of two samples were also studied. A total of 35 compounds were identified, of which all were present in single-flowered and 26 in double-flowered samples. The main aroma components were (E-β-ocimene, and benzyl acetate. Single-flowered narcissus have a higher percentage of benzyl acetate, while double-flowered narcissus have a higher percentage of 1,8-cineole. In vase-life, the total volatile component content peaked on day 2 for single-flowered and day 3 for the double-flowered narcissus. For both single-flowered and double-flowered narcissus flowers, the total content of volatile components had decreased significantly by day 4.

  8. Water Determination in Solid Pharmaceutical Products Utilizing Ionic Liquids and Headspace Gas Chromatography.

    Science.gov (United States)

    Frink, Lillian A; Armstrong, Daniel W

    2016-08-01

    A rapid, accurate, and precise headspace gas chromatographic (HSGC) analytical method was developed for the detection and quantification of water in drug products. The analysis is able to be performed in 10 min and automated. The HSGC method used an ionic liquid (IL) based open tubular capillary gas chromatographic column to increase the ruggedness of this method and provide improved peak shapes for water. Due to the ionic liquids low vapor pressure, unique physiochemical properties, and high thermal stability, they also make idea solvents for HSGC. Unlike Karl Fischer titration methods, this HSGC method is not affected by side reactions. The developed method was shown to be broadly applicable. The water content in 12 different samples was found to range from 1%-7% water. The use of HSGC was highly sensitive and only required 10 mg of sample. In addition, it was found to have greater precision and accuracy than Karl Fischer titration and greater precision and speed than loss on drying.

  9. Endemic Balkan parsnip Pastinaca hirsuta: the chemical profile of essential oils, headspace volatiles and extracts.

    Science.gov (United States)

    Jovanović, Snežana Č; Jovanović, Olga P; Petrović, Goran M; Stojanović, Gordana S

    2015-04-01

    The present study for the first time reports the chemical composition of the endemic Balkan parsnip Pastinaca hirsuta Pančić essential oil and headspace (HS) volatiles, obtained from fresh roots, stems, flowers and fruits, as well as fresh fruits n-hexane and diethyl ether extracts. According to GC-MS and GC-FID analyses, β-Pinene was one of the major components of the root and stem HS volatiles (50.6-24.1%). (E)-β-Ocimene was found in a significant percentage in the stem and flowers HS volatiles (31.6-57.3%). The most abundant constituent of the fruit HS, flower and fruit essential oils and both extracts was hexyl butanoate (70.5%, 31.1%, 80.4%, 47.4% and 52.7%, respectively). Apiole, accompanied by myristicin and (Z)-falcarinol, make up over 70% of the root essential oils. γ-Palmitolactone was the major component of the stem essential oils (51.9% at the flowering stage and 45.7% at the fruiting stage). Beside esters as dominant compounds, furanocoumarins were also identified in extracts. (Dis)similarity relations of examined plant samples were also investigated by the agglomerative hierarchical cluster analysis. The obtained results show there is difference in the composition of volatile components from different plant organs, while the stage of growth mainly affects the quantitative volatiles composition.

  10. Automated dynamic headspace/GC-MS analyses affect the repeatability of volatiles in irradiated Turkey.

    Science.gov (United States)

    Nam, Ki-Chang; Cordray, Joseph; Ahn, Dong U

    2004-03-24

    Although a dynamic headspace/gas chromatography-mass spectrometry (DH/GC-MS) method is an effective tool for determining volatiles of irradiated turkey meat, the profile of volatiles may be changeable depending upon the availability of oxygen in the sample vial and sample holding time before purge. The objective of this study was to evaluate the effects of helium flushing and sample holding time before purge on the volatiles profiles of irradiated raw and cooked turkey breast meat. Vacuum-packaged turkey breasts were irradiated at 2.5 kGy, and the volatiles of irradiated raw and cooked samples were analyzed using a DH/GC-MS with different holding times up to 280 min. The amounts of dimethyl disulfide and dimethyl trisulfide decreased as sample holding time in an autosampler (4 degrees C) before purge increased, whereas those of aldehdyes increased as holding time increased due to lipid oxidation. Helium flush of sample vials before sample loading on an autosampler retarded lipid oxidation and minimized the changes of sulfur volatiles in raw meat but was not enough to prevent oxidative changes in cooked meat. Although DH/GC-MS is a convenient method for automatic analysis of volatiles in meat samples, the number of samples that can be loaded in an autosampler at a time should be limited within the range that can permit reasonable repeatabilities for target volatile compounds.

  11. Determination of benzene residues in recycled polyethylene terephthalate (PETE) by dynamic headspace-gas chromatography.

    Science.gov (United States)

    Komolprasert, V; Hargraves, W A; Armstrong, D J

    1994-01-01

    A dynamic headspace-gas chromatography (HS/GC) method was developed to quantitate benzene in recycled PETE material derived from 21 PETE beverage bottles. The analytical system consisted of a purge-and-trap apparatus which was interfaced directly with a gas chromatograph/flame ionization detector. Cryofocusing and non-cryofocusing GC systems were used. The technique was applied to spiked PETE test samples which were prepared at various benzene concentrations ranging from 100 ppb to 117 ppm. The initial spiked benzene concentration in the PETE test samples was determined gravimetrically. The HS/GC technique was limited by the slow desorption rate of benzene from the PETE matrix; as a result, multipurges were performed at 60 degrees C. Regression analysis was done on the multipurge data to develop a desorption model which would predict the total amount of benzene in the PETE. The calculated results agreed with the experimental recoveries within +/- 10%. Recovery depended on the initial benzene level in the PETE and ranged from 70 to 90% after the first five purges.

  12. On-matrix derivatization for dynamic headspace sampling of nonvolatile surface residues.

    Science.gov (United States)

    Harvey, Scott D; Wahl, Jon H

    2012-09-21

    The goal of this study is to extend sampling by the field and laboratory emission cell (FLEC) dynamic headspace technique to applications that target nonvolatile residues. On-matrix derivatization of residues to render analytes stable and more volatile is explored to achieve this goal. Results show that on-matrix derivatizations of nerve agent hydrolysis products (monoalkyl methylphosphonic acids and methylphosphonic acid [MPA]) with diazomethane were successful on glass and painted wallboard (at the 10-μg level). It also was successful on the more difficult concrete (at the 500-μg level) and carpet (at the 20-μg level), substrates that cannot be successfully sampled using swipe techniques. Analysis of additional chemical warfare (CW)-associated residues can be approached by on-matrix derivatization with trifluoroacetic anhydride (TFAA). For example, amines (used as stabilizers or present as decomposition products of the nerve agent VX) or thiodiglycol (hydrolysis product of sulfur mustard) could be sampled as their TFAA derivatives from glass, painted wallboard, and concrete (at the 40-μg level), as well as carpet (at the 80-μg level) surfaces. Although the amine and thiodiglycol are semi-volatile and could be sampled directly, derivatization improves the recovery and chromatographic behavior of these analytes.

  13. Effects of gas composition in headspace and bicarbonate concentrations in media on gas and methane production, degradability, and rumen fermentation using in vitro gas production techniques.

    Science.gov (United States)

    Patra, Amlan Kumar; Yu, Zhongtang

    2013-07-01

    Headspace gas composition and bicarbonate concentrations in media can affect methane production and other characteristics of rumen fermentation in in vitro gas production systems, but these 2 important factors have not been evaluated systematically. In this study, these 2 factors were investigated with respect to gas and methane production, in vitro digestibility of feed substrate, and volatile fatty acid (VFA) profile using in vitro gas production techniques. Three headspace gas compositions (N2+ CO2+ H2 in the ratio of 90:5:5, CO2, and N2) with 2 substrate types (alfalfa hay only, and alfalfa hay and a concentrate mixture in a 50:50 ratio) in a 3×2 factorial design (experiment 1) and 3 headspace compositions (N2, N2 + CO2 in a 50:50 ratio, and CO2) with 3 bicarbonate concentrations (80, 100, and 120 mM) in a 3×3 factorial design (experiment 2) were evaluated. In experiment 1, total gas production (TGP) and net gas production (NGP) was the lowest for CO2, followed by N2, and then the gas mixture. Methane concentration in headspace gas after fermentation was greater for CO2 than for N2 and the gas mixture, whereas total methane production (TMP) and net methane production (NMP) were the greatest for CO2, followed by the gas mixture, and then N2. Headspace composition did not affect in vitro digestibility or the VFA profile, except molar percentages of propionate, which were greater for CO2 and N2 than for the gas mixture. Methane concentration in headspace gas, TGP, and NGP were affected by the interaction of headspace gas composition and substrate type. In experiment 2, increasing concentrations of CO2 in the headspace decreased TGP and NGP quadratically, but increased the concentrations of methane, NMP, and in vitro fiber digestibility linearly, and TMP quadratically. Fiber digestibility, TGP, and NGP increased linearly with increasing bicarbonate concentrations in the medium. Concentrations of methane and NMP were unaffected by bicarbonate concentration, but

  14. Summary and evaluation of existing geological and geophysical data near prospective surface facilities in Midway Valley, Yucca Mountain Project, Nye County, Nevada; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, J.D. [Sandia National Labs., Albuquerque, NM (United States); Swan, F.H.; Wesling, J.R.; Bullard, T.F.; Perman, R.C.; Angell, M.M.; DiSilvestro, L.A. [Geomatrix Consultants, Inc., San Francisco, CA (United States)

    1992-01-01

    Midway Valley, located at the eastern base of the Yucca Mountain in southwestern Nevada, is the preferred location of the surface facilities for the potential high-level nuclear waste repository at Yucca Mountain. One goal in siting these surface facilities is to avoid faults that could produce relative displacements in excess of 5 cm in the foundations of the waste-handling buildings. This study reviews existing geologic and geophysical data that can be used to assess the potential for surface fault rupture within Midway Valley. Dominant tectonic features in Midway Valley are north-trending, westward-dipping normal faults along the margins of the valley: the Bow Ridge fault to the west and the Paintbrush Canyon fault to the east. Published estimates of average Quaternary slip rates for these faults are very low but the age of most recent displacement and the amount of displacement per event are largely unknown. Surface mapping and interpretive cross sections, based on limited drillhole and geophysical data, suggest that additional normal faults, including the postulated Midway Valley fault, may exist beneath the Quaternary/Tertiary fill within the valley. Existing data, however, are inadequate to determine the location, recency, and geometry of this faulting. To confidently assess the potential for significant Quaternary faulting in Midway Valley, additional data are needed that define the stratigraphy and structure of the strata beneath the valley, characterize the Quaternary soils and surfaces, and establish the age of faulting. The use of new and improved geophysical techniques, combined with a drilling program, offers the greatest potential for resolving subsurface structure in the valley. Mapping of surficial geologic units and logging of soil pits and trenches within these units must be completed, using accepted state-of-the-art practices supported by multiple quantitative numerical and relative age-dating techniques.

  15. Chemical characterization and source apportionment estimates of particulate matter collected within the framework of EU project HEPMEAP

    OpenAIRE

    Bloemen HJT; Gerlofs-Nijland ME; Janssen NAH; Sandstrom T; Bree L van; Cassee FR; LVM; MGO; LOK

    2005-01-01

    Een groot deel van de massa van het fijnstof bestaat uit anorganisch aerosol (34% nitraat, sulfaat en ammonium). Daarnaast bestaat circa 2% uit organisch materiaal afkomstig van verbrandingsprocessen. Ruwe schattingen van de verkeersbijdrage voor deze twee fracties varieren tussen 30% en 60%. In het kader van het project 'Health effects of particles from motor engine exhaust and ambient pollution - HEPMEAP', een unieke Europese samenwerking tussen toxicologen en epidemiologen, is bu...

  16. [Determination of residual organic solvents in flunixin meglumine raw material by headspace gas chromatography].

    Science.gov (United States)

    Hu, Huilian

    2012-01-01

    A method for the determination of five kinds of residual organic solvents in flunixin meglumine raw material was developed by headspace gas chromatography. An HP-FFAP capillary column (30 m x 0.32 mm x 1.0 microm), a flame ionization detector and the external standard method were used for the separation and quantitative analysis. The effects of equilibrium temperature and equilibrium time on the determination of residual organic solvents were investigated. The good results were obtained in the equilibrium temperature of 90 degrees C and equilibrium time of 30 min. The standard curves were linear in the range of 0.40-7.93 mg/L (r = 0.999 8) for ethyl acetate, 7.32-146.48 mg/L (r = 0.999 6) for methanol, 4.53-90.61 mg/L (r = 0.999 9) for isopropanol, 3.62-72.32 mg/L (r = 0.999 8) for ethanol and 2.31-46.24 mg/L (r = 0.999 6) for acetonitrile. The recoveries for the five residual organic solvents were between 95.96% and 100.31% with relative standard deviations (RSDs) (n = 6) of 1.97%-3.28%. The detection limits of ethyl acetate, methanol, isopropanol, ethanol and acetonitrile were 0.08, 0.9, 0.2, 0.4 and 0.3 mg/L, respectively. The proposed method was successfully applied to analyze the residual organic solvents in the real sample of flunixin meglumine raw material. The results showed that only isopropanol and ethanol were found in the sample with the contents of 177.44 microg/g and 69.32 microg/g, respectively. The method is rapid, sensitive and accurate for the content determination of residual solvents in flunixin meglumine raw material.

  17. Multivariate optimization of headspace trap for furan and furfural simultaneous determination in sponge cake.

    Science.gov (United States)

    Cepeda-Vázquez, Mayela; Blumenthal, David; Camel, Valérie; Rega, Barbara

    2017-03-01

    Furan, a possibly carcinogenic compound to humans, and furfural, a naturally occurring volatile contributing to aroma, can be both found in thermally treated foods. These process-induced compounds, formed by close reaction pathways, play an important role as markers of food safety and quality. A method capable of simultaneously quantifying both molecules is thus highly relevant for developing mitigation strategies and preserving the sensory properties of food at the same time. We have developed a unique reliable and sensitive headspace trap (HS trap) extraction method coupled to GC-MS for the simultaneous quantification of furan and furfural in a solid processed food (sponge cake). HS Trap extraction has been optimized using an optimal design of experiments (O-DOE) approach, considering four instrumental and two sample preparation variables, as well as a blocking factor identified during preliminary assays. Multicriteria and multiple response optimization was performed based on a desirability function, yielding the following conditions: thermostatting temperature, 65°C; thermostatting time, 15min; number of pressurization cycles, 4; dry purge time, 0.9min; water / sample amount ratio (dry basis), 16; and total amount (water + sample amount, dry basis), 10g. The performances of the optimized method were also assessed: repeatability (RSD: ≤3.3% for furan and ≤2.6% for furfural), intermediate precision (RSD: 4.0% for furan and 4.3% for furfural), linearity (R(2): 0.9957 for furan and 0.9996 for furfural), LOD (0.50ngfuran gsample dry basis(-1) and 10.2ngfurfural gsample dry basis(-1)), LOQ (0.99ngfuran gsample dry basis(-1) and 41.1ngfurfural gsample dry basis(-1)). Matrix effect was observed mainly for furan. Finally, the optimized method was applied to other sponge cakes with different matrix characteristics and levels of analytes.

  18. A rapid analysis of plasma/serum ethylene and propylene glycol by headspace gas chromatography.

    Science.gov (United States)

    Ehlers, Alexandra; Morris, Cory; Krasowski, Matthew D

    2013-12-01

    A rapid headspace-gas chromatography (HS-GC) method was developed for the analysis of ethylene glycol and propylene glycol in plasma and serum specimens using 1,3-propanediol as the internal standard. The method employed a single-step derivitization using phenylboronic acid, was linear to 200 mg/dL and had a lower limit of quantitation of 1 mg/dL suitable for clinical analyses. The analytical method described allows for laboratories with HS-GC instrumentation to analyze ethanol, methanol, isopropanol, ethylene glycol, and propylene glycol on a single instrument with rapid switch-over from alcohols to glycols analysis. In addition to the novel HS-GC method, a retrospective analysis of patient specimens containing ethylene glycol and propylene glycol was also described. A total of 36 patients ingested ethylene glycol, including 3 patients who presented with two separate admissions for ethylene glycol toxicity. Laboratory studies on presentation to hospital for these patients showed both osmolal and anion gap in 13 patients, osmolal but not anion gap in 13 patients, anion but not osmolal gap in 8 patients, and 1 patient with neither an osmolal nor anion gap. Acidosis on arterial blood gas was present in 13 cases. Only one fatality was seen; this was a patient with initial serum ethylene glycol concentration of 1282 mg/dL who died on third day of hospitalization. Propylene glycol was common in patients being managed for toxic ingestions, and was often attributed to iatrogenic administration of propylene glycol-containing medications such as activated charcoal and intravenous lorazepam. In six patients, propylene glycol contributed to an abnormally high osmolal gap. The common presence of propylene glycol in hospitalized patients emphasizes the importance of being able to identify both ethylene glycol and propylene glycol by chromatographic methods.

  19. Fractionated dynamic headspace sampling in the analysis of matrices of vegetable origin in the food field.

    Science.gov (United States)

    Liberto, Erica; Cagliero, Cecilia; Cordero, Chiara; Rubiolo, Patrizia; Bicchi, Carlo; Sgorbini, Barbara

    2017-03-17

    Recent technological advances in dynamic headspace sampling (D-HS) and the possibility to automate this sampling method have lead to a marked improvement in its the performance, a strong renewal of interest in it, and have extended its fields of application. The introduction of in-parallel and in-series automatic multi-sampling and of new trapping materials, plus the possibility to design an effective sampling process by correctly applying the breakthrough volume theory, have make profiling more representative, and have enhanced selectivity, and flexibility, also offering the possibility of fractionated enrichment in particular for high-volatility compounds. This study deals with fractionated D-HS ability to produce a sample representative of the volatile fraction of solid or liquid matrices. Experiments were carried out on a model equimolar (0.5mM) EtOH/water solution, comprising 16 compounds with different polarities and volatilities, structures ranging from C5 to C15 and vapor pressures from 4.15kPa (2,3-pentandione) to 0.004kPa (t-β-caryophyllene), and on an Arabica roasted coffee powder. Three trapping materials were considered: Tenax TA™ (TX), Polydimethylsiloxane foam (PDMS), and a three-carbon cartridge Carbopack B/Carbopack C/Carbosieve S-III™ (CBS). The influence of several parameters on the design of successful fractionated D-HS sampling. Including the physical and chemical characteristics of analytes and matrix, trapping material, analyte breakthrough, purge gas volumes, and sampling temperature, were investigated. The results show that, by appropriately choosing sampling conditions, fractionated D-HS sampling, based on component volatility, can produce a fast and representative profile of the matrix volatile fraction, with total recoveries comparable to those obtained by full evaporation D-HS for liquid samples, and very high concentration factors for solid samples.

  20. Calculation and verification of blood ethanol measurement uncertainty for headspace gas chromatography.

    Science.gov (United States)

    Sklerov, Jason H; Couper, Fiona J

    2011-09-01

    An estimate was made of the measurement uncertainty for blood ethanol testing by headspace gas chromatography. While uncertainty often focuses on compliance to a single threshold level (0.08 g/100 mL), the existence of multiple thresholds, related to enhanced sentencing, subject age, or commercial vehicle licensure, necessitate the use of an estimate with validity across multiple specification levels. The uncertainty sources, in order of decreasing magnitude, were method reproducibility, linear calibration, recovery, calibrator preparation, reference material, and sample preparation. A large set of reproducibility data was evaluated (n = 15,433) in order to encompass measurement variability across multiple conditions, operators, instruments, concentrations and timeframes. The relative, combined standard uncertainty was calculated as ±2.7%, with an expanded uncertainty of ±8.2% (99.7% level of confidence, k = 3). Bias was separately evaluated through a recovery study using standard reference material from a national metrology institute. The uncertainty estimate was verified through the use of proficiency test (PT) results. Assigned values for PT results and their associated uncertainties were calculated as robust means (x*) and standard deviations (s*) of participant values. Performance scores demonstrated that the uncertainty estimate was appropriate across the full range of PT concentrations (0.010-0.370 g/100 mL). The use of PT data as an empirical estimate of uncertainty was not examined. Until providers of blood ethanol PT samples include details on how an assigned value is obtained along with its uncertainty and traceability, the use of PT data should be restricted to the role of verification of uncertainty estimates.

  1. Identificação e quantificação de voláteis de café através de cromatografia gasosa de alta resolução / espectrometria de massas empregando um amostrador automático de "headspace" Identification and quantification of coffee volatile components through high resolution gas chromatoghaph/mass spectrometer using a headspace automatic sampler

    Directory of Open Access Journals (Sweden)

    Leonardo César AMSTALDEN

    2001-01-01

    Full Text Available Usando um amostrador automático, os "headspaces" de três marcas comerciais de café torrado e moído foram analisados qualitativa e quantitativamente quanto a composição dos voláteis responsáveis pelo aroma através da técnica de cromatografia gasosa/espectrometria de massas. Uma vez que a metodologia não envolveu isolamento ou concentração dos aromas, suas proporções naturais foram mantidas, além de simplificar o preparo das amostras. O emprego do amostrador automático permitiu também boa resolução dos picos cromatográficos sem o emprego de criogenia, contribuindo para redução no tempo de análise. Noventa e um componentes puderam ser identificados, sendo que alguns compostos conhecidos como presentes em café como o dimetilsulfeto, metional e furfuril mercaptana não foram detectados. Os voláteis presentes em maior concentração puderam ser quantificados com o auxílio de dois padrões internos. A técnica se provou viável, tanto para caracterização como para quantificação de voláteis de café.Employing an automatic headspace sampler, the headspaces of three commercial brands of ground roasted coffee were qualitatively and quantitatively analyzed by gas chromatography / mass spectrometry. Since the methodology did not involve aroma isolation or concentration, their natural proportions were maintained, providing a more accurate composition of the flavors, and simplifying sample preparation. The automatic sampler allowed good resolution of the chromatographic peaks without cryofocusing the samples at the head of the column during injection, reducing analysis time. Ninety one compounds were identified and some known coffee volatiles, such as dimethyl sulphide, methional and furfuryl mercaptan were not detected. The more concentrated volatiles could be identified using two internal standards. The technique proved viable, for both characterization and for quantification of coffee volatiles.

  2. Syntheses and Characterization of Ruthenium(II) Tetrakis(pyridine)complexes: An Advanced Coordination Chemistry Experiment or Mini-Project

    Science.gov (United States)

    Coe, Benjamin J.

    2004-01-01

    An experiment for third-year undergraduate a student is designed which provides synthetic experience and qualitative interpretation of the spectroscopic properties of the ruthenium complexes. It involves the syntheses and characterization of several coordination complexes of ruthenium, the element found directly beneath iron in the middle of the…

  3. Design and testing of a new sampler for simplified vacuum-assisted headspace solid-phase microextraction.

    Science.gov (United States)

    Yiantzi, Evangelia; Kalogerakis, Nicolas; Psillakis, Elefteria

    2016-07-13

    The design and testing of a new and low-cost experimental setup used for vacuum-assisted headspace solid-phase microextraction (Vac-HSSPME) is reported here. The device consists of a specially designed O-ring seal screw cap offering gas-tight seal to commercially available headspace vials. The new polytetrafluoroethylene (PTFE) cap was molded by a local manufacturer and had a hole that could tightly accommodate a septum. All operations were performed through the septum: air evacuation of the sampler, sample introduction and HSSPME sampling. The analytical performance of the new sampler was evaluated using 22 mL headspace vials with 9 mL water samples spiked with polychlorinated biphenyls (PCBs). Several experimental parameters were controlled and the optimized conditions were: 1000 rpm agitation speed; 30 min extraction time; 40 °C sampling temperature; polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber. The lack of accurate Henry's law constant (KH) values and information regarding how they change with temperature was a major limitation in predicting the phase location of evaporation resistance during Vac-HSSPME. Nevertheless, the combined effects of system conditions indicated the increasing importance of gas phase resistance with increasing degree of PCBs chlorination. Stirring enhancements were not recorded for the higher chlorinated PCBs suggesting that the hyperhydrophobic gas/water interface was the preferred location for these compounds. Analytically, the developed method was found to yield linear calibration curves with limits of detection in the sub ng L(-1) level and relative standard deviations ranging between 5.8 and 14%. To compensate for the low recoveries of the higher chlorinated PCB congeners in spiked river water the standard addition methodology was applied. Overall, the compact design of the new and reusable sample container allows efficient HSSPME sampling of organic analytes in water within short extraction times and at low sampling

  4. Comparative study of the whisky aroma profile based on headspace solid phase microextraction using different fibre coatings.

    Science.gov (United States)

    Câmara, J S; Marques, J C; Perestrelo, R M; Rodrigues, F; Oliveira, L; Andrade, P; Caldeira, M

    2007-05-25

    A dynamic headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled to ion trap mass spectrometry (GC-(IT)MS) method was developed and applied for the qualitative determination of the volatile compounds present in commercial whisky samples which alcoholic content was previously adjusted to 13% (v/v). Headspace SPME experimental conditions, such as fibre coating, extraction temperature and extraction time, were optimized in order to improve the extraction process. Five different SPME fibres were used in this study, namely, poly(dimethylsiloxane) (PDMS), poly(acrylate) (PA), Carboxen-poly(dimethylsiloxane) (CAR/PDMS), Carbowax-divinylbenzene (CW/DVB) and Carboxen-poly(dimethylsiloxane)-divinylbenzene (CAR/PDMS/DVB). The best results were obtained using a 75 microm CAR/PDMS fibre during headspace extraction at 40 degrees C with stirring at 750 rpm for 60 min, after saturating the samples with salt. The optimised methodology was then applied to investigate the volatile composition profile of three Scotch whisky samples--Black Label, Ballantines and Highland Clan. Approximately seventy volatile compounds were identified in the these samples, pertaining at several chemical groups, mainly fatty acids ethyl esters, higher alcohols, fatty acids, carbonyl compounds, monoterpenols, C13 norisoprenoids and some volatile phenols. The ethyl esters form an essential group of aroma components in whisky, to which they confer a pleasant aroma, with "fruity" odours. Qualitatively, the isoamyl acetate, with "banana" aroma, was the most interesting. Quantitatively, significant components are ethyl esters of caprilic, capric and lauric acids. The highest concentration of fatty acids, were observed for caprilic and capric acids. From the higher alcohols the fusel oils (3-methylbutan-1-ol and 2.phenyletanol) are the most important ones.

  5. Optimization of dynamic headspace extraction system for measurement of halogenated volatile organic compounds in liquid or viscous samples

    Science.gov (United States)

    Taniai, G.; Oda, H.; Kurihara, M.; Hashimoto, S.

    2010-12-01

    Halogenated volatile organic compounds (HVOCs) produced in the marine environment are thought to play a key role in atmospheric reactions, particularly those involved in the global radiation budget and the depression of tropospheric and stratospheric ozone. To evaluate HVOCs concentrations in the various natural samples, we developed an automated dynamic headspace extraction method for the determination of 15 HVOCs, such as chloromethane, bromomethane, bromoethane, iodomethane, iodoethane, bromochloromethane, 1-iodopropane, 2-iodopropane, dibromomethane, bromodichloromethane, chloroiodomethane, chlorodibromomethane, bromoiodomethane, tribromomethane, and diiodomethane. Dynamic headspace system (GERSTEL DHS) was used to purge the gas phase above samples and to trap HVOCs on the adsorbent column from the purge gas. We measured the HVOCs concentrations in the adsorbent column with gas chromatograph (Agilent 6890N)- mass spectrometer (Agilent 5975C). In dynamic headspace system, an glass tube containing Tenax TA or Tenax GR was used as adsorbent column for the collection of 15 HVOCs. The parameters for purge and trap extraction, such as purge flow rate (ml/min), purge volume (ml), incubation time (min), and agitator speed (rpm), were optimized. The detection limits of HVOCs in water samples were 1270 pM (chloromethane), 103 pM (bromomethane), 42.1 pM (iodomethane), and 1.4 to 10.2 pM (other HVOCs). The repeatability (relative standard deviation) for 15 HVOCs were < 9 % except chloromethane (16.2 %) and bromomethane (11.0 %). On the basis of the measurements for various samples, we concluded that this analytical method is useful for the determination of wide range of HVOCs with boiling points between - 24°C (chloromethane) and 181°C (diiodomethane) for the liquid or viscous samples.

  6. Dynamic headspace analysis of volatile metabolites from the reductive dehalogenation of trichloro- and tetrachloroethanes by hepatic microsomes.

    Science.gov (United States)

    Thompson, J A; Ho, B; Mastovich, S L

    1985-03-01

    A dynamic headspace technique was developed to facilitate the identification and quantitation of low levels of volatile metabolites produced in vitro by subcellular preparations. The method is complementary to commonly used static headspace and solvent-extraction techniques, and involves purging the compounds from microsomal suspensions with an inert gas, trapping them on a short column of adsorbant resin, and transferring the metabolites to a gas chromatograph. An apparatus was designed to facilitate the incubations and isolations of volatile compounds. Recoveries of several chlorinated hydrocarbons with boiling points in the range 12 to 186 degrees C were 85% or higher, and the recovery of vinyl chloride (boiling point -13 degrees C) was 25%. The quantitative precision of the method was determined and calibration curves were established for each metabolite, demonstrating that no discrimination occurred over a wide range of concentrations. This technique was employed to investigate the reductive metabolism of 1,1,1-trichloroethane, 1,1,2-trichloroethane, and 1,1,2,2-tetrachloroethane by rat liver microsomes. The metabolites from these substrates were 1,1-dichloroethane, vinyl chloride, and 1,2-dichloroethylene, respectively. These conversions were NADPH-dependent, occurred only under anaerobic conditions, and indicate that chloroethanes with relatively low electron affinities can be reduced slowly by microsomal cytochrome P-450. The rates of formation of vinyl chloride, 1,1-dichloroethane, and 1,2-dichloroethylene with 1.0 mM substrate were 12.5 +/- 2.0, 122 +/- 14, and 147 +/- 12 pmol/min/mg of protein, respectively. The results show that there are distinct advantages of the purge/trap method over the static headspace method for studying volatile metabolites when high sensitivity is required.

  7. Approach for tank safety characterization of Hanford site waste

    Energy Technology Data Exchange (ETDEWEB)

    Meacham, J.E.; Babad, H.; Cash, R.J.; Dukelow, G.T.; Eberlein, S.J.; Hamilton, D.W.; Johnson, G.D.; Osborne, J.W.; Payne, M.A.; Sherwood, D.J. [and others

    1995-03-01

    The overall approach and associated technical basis for characterizing Hanford Site waste to help identify and resolve Waste Tank Safety Program safety issues has been summarized. The safety issues include flammable gas, noxious vapors, organic solvents, condensed-phase exothermic reactions (ferrocyanide and organic complexants), criticality, high heat, and safety screening. For the safety issues involving chemical reactions (i.e., flammable gas, organic solvents, ferrocyanide, and organic complexants), the approach to safety characterization is based on the fact that rapid exothermic reactions cannot occur if either fuel, oxidizer, or temperature (initiators) is not sufficient or controlled. The approach to characterization has been influenced by the progress made since mid-1993: (1) completion of safety analyses on ferrocyanide, criticality, organic solvent in tank 241-C-103, and sludge dryout. (2) successful mitigation of tank 241-SY-101; (3) demonstration of waste aging in laboratory experiments and from waste sampling, and (4) increased understanding of the information that can be obtained from headspace sampling. Headspace vapor sampling is being used to confirm that flammable gas does not accumulate in the single-shell tanks, and to determine whether organic solvents are present. The headspaces of tanks that may contain significant quantities of flammable gas will be monitored continuously using standard hydrogen monitors. For the noxious vapors safety issue, characterization will consist of headspace vapor sampling of most of the Hanford Site waste tanks. Sampling specifically for criticality is not required to confirm interim safe storage; however, analyses for fissile material will be conducted as waste samples are obtained for other reasons. High-heat tanks will be identified through temperature monitoring coupled with thermal analyses.

  8. Fast analysis of volatile components of Achillea tenuifolia Lam with microwave distillation followed by headspace single-drop microextraction coupled to gas chromatography-mass spectrometry (GC-MS).

    Science.gov (United States)

    Piryaei, Marzieh; Nazemiyeh, Hossein

    2016-01-01

    This article investigates the effect of microwaves on the amount of volatile compounds Achillea tenuifolia Lam with two methods, headspace single-drop microextraction and microwave-assisted headspace single-drop microextraction (MA-SDME), for the analysis of essential oil. Solvent selection, solvent volume, microwave power, irradiation time and sample mass were optimised by the simplex method.

  9. Comparison of quarter-hourly on-line dynamic headspace analysis to purge-and-trap analysis of varying volatile organic compounds in drinking water sources.

    Science.gov (United States)

    Schnable, J G; Dussert, B; Suffet, I H; Hertz, C D

    1990-07-27

    On-line dynamic headspace analysis was refined for the quarter-hourly monitoring of select volatile organic compounds (VOCs) in ground and surface waters, for extended periods of time. Hourly comparisons were made to on-line purge-and-trap analysis, and to purge-and-trap analysis after sample preservation and storage. Variations in VOC concentrations of 6047% biweekly, 222% daily, 97% hourly, and 35% quarter-hourly were observable, with the 15-min cycle of the dynamic headspace analysis. The headspace analyzer had superior retention time stability, required less maintenance, and had 1/4 the analysis time as a typical purge-and-trap-gas chromatograph system used for hourly comparisons.

  10. Furan determination in jarred baby food purchased from the Spanish market by headspace gas chromatography-mass spectrometry.

    OpenAIRE

    Ruiz, Elvira

    2010-01-01

    Abstract The aim of this paper is to offer a method based on headspace gas chromatography-mass spectrometry technique (US FDA 2006) in-house validated and used to estimate furan concentrations in jarred baby food samples purchased from the Spanish market. The validation was performed according to ISO 17025 and EFSA requirements and the results obtained (LOD 0.05 ?g.kg-1; LOQ 4 ?g.kg-1, lowest validated level; RSD% 3.1-10.5; recoveries 85.4-101.5%) confirm that this method is fit fo...

  11. Optimization of dynamic headspace extraction of the edible red algae Palmaria palmata and identification of the volatile components.

    Science.gov (United States)

    Le Pape, Marie-Annick; Grua-Priol, Joëlle; Prost, Carole; Demaimay, Michel

    2004-02-11

    A new extraction method was applied to the volatile compounds of Palmaria palmata. Dynamic headspace was optimized according to an experimental design, and descriptive sensory analysis and intensity and similarity tests were performed for each extract to assess their respective representativeness. Results showed that extract obtained with crushed algae after a 30 min purge was the most representative. GC-MS analysis was then performed on this extract to identify the volatile components. Seven halogenated compounds, seven aldehydes, two ketones, three alcohols, and four miscellaneous compounds were identified. Among them, halogenated compounds were the most characteristic of red algae, and more particularly, iodoethane and iodopentane, which had yet been found in other seaweeds.

  12. Choice and use of standards for dynamic headspace trapping and application to the analysis of the volatiles of baked potato.

    Science.gov (United States)

    Ames, J M; Duckham, S C; Bakker, J

    2001-01-01

    When attempting to quantify the volatile components of a food isolated by dynamic headspace trapping onto an adsorbent, the analyst has to select the most appropriate compounds to use as standards and at which stage of the analysis to add them. Factors to be borne in mind include the volatility of the standard, the response of the GC detector, and whether to add the standard to the sample or to the adsorbent trap. This chapter considers the issues and describes the application of one chosen method to the quantitation of the volatile components of baked potato.

  13. Understanding the role of saliva in aroma release from wine by using static and dynamic headspace conditions

    OpenAIRE

    Muñoz-González, Carolina; Feron, Gilles; GUICHARD, Elisabeth; Rodríguez-Bencomo, Juan José; Pedro J. Martín-Álvarez; Moreno-Arribas, M. Victoria; Pozo-Bayón, Mª Ángeles

    2014-01-01

    The aim of this work was to determine the role of saliva in wine aroma release by using static and dynamic headspace conditions. In the latter conditions, two different sampling points (t = 0 and t = 10 min) corresponding with oral (25.5 °C) and postoral phases (36 °C) were monitored. Both methodologies were applied to reconstituted dearomatized white and red wines with different nonvolatile wine matrix compositions and a synthetic wine (without matrix effect). All of the wines had the same e...

  14. Report of early site suitability evaluation of the potential repository site at Yucca Mountain, Nevada; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Younker, J.L.; Andrews, W.B.; Fasano, G.A.; Herrington, C.C.; Mattson, S.R.; Murray, R.C. [Science Applications International Corp., Las Vegas, NV (United States); Ballou, L.B.; Revelli, M.A. [Lawrence Livermore National Lab., CA (United States); Ducharme, A.R.; Shephard, L.E. [Sandia National Labs., Albuquerque, NM (United States); Dudley, W.W.; Hoxie, D.T. [Geological Survey, Denver, CO (United States); Herbst, R.J.; Patera, E.A. [Los Alamos National Lab., NM (United States); Judd, B.R. [Decision Analysis Co., Portola Valley, CA (United States); Docka, J.A.; Rickertsen, L.D. [Weston Technical Associates, Washington, DC (United States)

    1992-01-01

    This study evaluated the technical suitability of Yucca Mountain, Nevada, as a potential site for a mined geologic repository for the permanent disposal of radioactive waste. The evaluation was conducted primarily to determine early in the site characterization program if there are any features or conditions at the site that indicate it is unsuitable for repository development. A secondary purpose was to determine the status of knowledge in the major technical areas that affect the suitability of the site. This early site suitability evaluation (ESSE) was conducted by a team of technical personnel at the request of the Associate Director of the US Department of Energy (DOE) Office of Geologic Disposal, a unit within the DOE`s Office of Civilian Radioactive Waste Management. The Yucca Mountain site has been the subject of such evaluations for over a decade. In 1983, the site was evaluated as part of a screening process to identify potentially acceptable sites. The site was evaluated in greater detail and found suitable for site characterization as part of the Environmental Assessment (EA) (DOE, 1986) required by the Nuclear Waste Policy Act of 1982 (NWPA). Additional site data were compiled during the preparation of the Site Characterization Plan (SCP) (DOE, 1988a). This early site suitability evaluation has considered information that was used in preparing both-documents, along with recent information obtained since the EA and SCP were published. This body of information is referred to in this report as ``current information`` or ``available evidence.``

  15. Molecular and Cellular Characterization of Space Flight Effects on Microvascular Endothelial Cell Function - PreparatoryWork for the SFEF Project

    Science.gov (United States)

    Balsamo, Michele; Barravecchia, Ivana; Mariotti, Sara; Merenda, Alessandra; De Cesari, Chiara; Vukich, Marco; Angeloni, Debora

    2014-12-01

    Exposure to microgravity during space flight (SF) of variable length induces suffering of the endothelium (the cells lining all blood vessels), mostly responsible for health problems found in astronauts and animals returning from space. Of interest to pre-nosological medicine, the effects of microgravity on astronauts are strikingly similar to the consequences of sedentary life, senescence and degenerative diseases on Earth, although SF effects are accelerated and reversible. Thus, microgravity is a significant novel model for better understanding of common pathologies. A comprehensive cell and molecular biology study is needed in order to explain pathophysiological findings after SFs. This project will study the effects of microgravity and cosmic radiation on endothelial cells (ECs) cultured on the International Space Station through analysis of 1) cell transcriptome, 2) DNA methylome, 3) DNA damage and cell senescence, 4) variations in cell cycle and cell morphology. This project has been selected by the European Space Agency and the Italian Space Agency and is presently in preparation. The ground study presented here was performed to determine the biological and engineering requirements that will allow us to retrieve suitable samples after culturing, fixing and storing ECs in space. We expect to identify molecular pathways activated by space microgravity in microvascular ECs, which may shed light on pathogenic molecular mechanisms responsible for endothelial suffering shared by astronauts and individuals affected with aging, degenerative and sedentary life-associated pathologies on Earth.

  16. A demonstration of remote survey and characterization of a buried waste site using the SRIP (Soldier Robot Interface Project) testbed

    Energy Technology Data Exchange (ETDEWEB)

    Burks, B.L.; Richardson, B.S.; Armstrong, G.A.; Hamel, W.R.; Jansen, J.F.; Killough, S.M.; Thompson, D.H.; Emery, M.S.

    1990-01-01

    During FY 1990, the Oak Ridge National Laboratory (ORNL) supported the Department of Energy (DOE) Environmental Restoration and Waste Management (ER WM) Office of Technology Development through several projects including the development of a semiautonomous survey of a buried waste site using a remotely operated all-terrain robotic testbed borrowed from the US Army. The testbed was developed for the US Army's Human Engineering Laboratory (HEL) for the US Army's Soldier Robot Interface Project (SRIP). Initial development of the SRIP testbed was performed by a team including ORNL, HEL, Tooele Army Depot, and Odetics, Inc., as an experimental testbed for a variety of human factors issues related to military applications of robotics. The SRIP testbed was made available to the DOE and ORNL for the further development required for a remote landfill survey. The robot was modified extensively, equipped with environmental sensors, and used to demonstrate an automated remote survey of Solid Waste Storage Area No. 3 (SWSA 3) at ORNL on Tuesday, September 18, 1990. Burial trenches in this area containing contaminated materials were covered with soil nearly twenty years ago. This paper describes the SRIP testbed and work performed in FY 1990 to demonstrate a semiautonomous landfill survey at ORNL. 5 refs.

  17. Direct synthesis of nitrogen-doped graphene on platinum wire as a new fiber coating method for the solid-phase microextraction of BXes in water samples: Comparison of headspace and cold-fiber headspace modes.

    Science.gov (United States)

    Memarian, Elham; Hosseiny Davarani, Saied Saeed; Nojavan, Saeed; Movahed, Siyavash Kazemi

    2016-09-01

    In this work, a new solid-phase microextraction fiber was prepared based on nitrogen-doped graphene (N-doped G). Moreover, a new strategy was proposed to solve problems dealt in direct coating of N-doped G. For this purpose, first, Graphene oxide (GO) was coated on Pt wire by electrophoretic deposition method. Then, chemical reduction of coated GO to N-doped G was accomplished by hydrazine and NH3. The prepared fiber showed good mechanical and thermal stabilities. The obtained fiber was used in two different modes (conventional headspace solid-phase microextraction and cold-fiber headspace solid-phase microextraction (CF-HS-SPME)). Both modes were optimized and applied for the extraction of benzene and xylenes from different aqueous samples. All effective parameters including extraction time, salt content, stirring rate, and desorption time were optimized. The optimized CF-HS-SPME combined with GC-FID showed good limit of detections (LODs) (0.3-2.3 μg/L), limit of quantifications (LOQs) (1.0-7.0 μg/L) and linear ranges (1.0-5000 μg/L). The developed method was applied for the analysis of benzene and xylenes in rainwater and some wastewater samples.

  18. Analyses of nitrobenzene,benzene and aniline in environmental water samples by headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    CHEN Ming; YIN Yongguang; TAI Chao; ZHANG Qinghua; LIU Jiyan; HU Jingtian; JIANG Guibin

    2006-01-01

    A headspace solid phase microextraction coupled with gas chromatography mass spectrometry (HS-SPME/GC-MS) method was established for analyzing nitrobenzene, benzene and aniline in environmental water samples simultaneously.Factors affecting extraction efficiency (SPME fiber selection, acidity, temperature, salt addition, extraction time, headspace, etc) were verified. Under optimal extraction conditions, the detection limits are 0.50, 0.11 and 1.00 μg/L for nitrobenzene, benzene and aniline, respectively. The results indicate that this method is capable of making sensitive and accuracy analyses on nitrobenzene, benzene and aniline in environmental water samples.

  19. Fabrication of novel nanoporous array anodic alumina solid-phase microextraction fiber coating and its potential application for headspace sampling of biological volatile organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Zhuomin [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Wang Qingtang [Key Laboratory of Analysis and Detection for Food Safety of Ministry of Education, College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou, Fujian 350002 (China); Li Gongke, E-mail: cesgkl@mail.sysu.edu.cn [School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China)

    2012-05-21

    Highlights: Black-Right-Pointing-Pointer Nanoporous array anodic alumina (NAAA) SPME coating was originally prepared. Black-Right-Pointing-Pointer NAAA SPME coating achieved excellent enrichment capability and selectivity for VOCs. Black-Right-Pointing-Pointer NAAA SPME coating can be applied for the headspace sampling of biological VOCs. - Abstract: In the study, nanoporous array anodic alumina (NAAA) prepared by a simple, rapid and stable two-step anodic oxidization method was introduced as a novel solid-phase microextraction (SPME) fiber coating. The regular nanoporous array structure and chemical composition of NAAA SPME fiber coating was characterized and validated by scanning electron microscopy and energy dispersive spectroscopy, respectively. Compared with the commercial polydimethylsiloxane (PDMS) SPME fiber coating, NAAA SPME fiber coating achieved the higher enrichment capability (1.7-4.7 folds) for the mixed standards of volatile organic compounds (VOCs). The selectivity for volatile alcohols by NAAA SPME fiber coating demonstrated an increasing trend with the increasing polarity of alcohols caused by the gradually shortening carbon chains from 1-undecanol to 1-heptanol or the isomerization of carbon chains of some typical volatile alcohols including 2-ethyl hexanol, 1-octanol, 2-phenylethanol, 1-phenylethanol, 5-undecanol, 2-undecanol and 1-undecanol. Finally, NAAA SPME fiber coating was originally applied for the analysis of biological VOCs of Bailan flower, stinkbug and orange peel samples coupled with gas chromatography-mass spectrometry (GC-MS) detection. Thirty, twenty-seven and forty-four VOCs of Bailan flower, stinkbug and orange peel samples were sampled and identified, respectively. Moreover, the contents of trace 1-octanol and nonanal of real orange peel samples were quantified for the further method validation with satisfactory recoveries of 106.5 and 120.5%, respectively. This work proposed a sensitive, rapid, reliable and convenient

  20. DECOVALEX-THMC Project. Task B. Understanding and characterizing the excavation disturbed zone (EDZ). Phase 2 Report

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, John A. (ed.) [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)]|[Rock Engineering Consultants (United Kingdom); Lanru Jing (ed.) [Royal Institute of Technology, Stockholm (Sweden); Antikainen, Juha [Helsinki University of Technology, Helsinki (Finland); Backers, Tobias [GeoFrames GmbH, (Germany); Baeckstroem, Ann [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)]|[Bergbyggkonsult AB (Sweden); Koyama, Tomofumi [Swedish Nuclear Power Inspectorate, Stockholm (Sweden); Xiating Feng; Pengzhi Pan [Chinese Academy of Sciences (China); Kobayashi, Akira [Kyoto Univ. (Japan); Rinne, Mikael; Baotang Shen [Fracom Ltd. (Finland)

    2007-02-15

    The DECOVALEX-THMC project is an ongoing international co-operative project that was stared in 2004 to support the development of mathematical models of coupled Thermal (T), Hydrological (H), Mechanical (M) and Chemical (C) processes in geological media for siting potential nuclear fuel waste repositories. The general objective is to characterise and evaluate the coupled THMC processes in the near field and far field of a geological repository and to assess their impact on performance assessment: - during the three phases of repository development: excavation phase, operation phase and post-closure phase; - for three different rocks types: crystalline, argillaceous and tuff; - with specific focus on the issues of: Excavation Damaged Zone (EDZ), permanent property changes of rock masses, and glaciation and permafrost phenomena. The project involves a large number of research teams supported by radioactive waste management agencies or governmental regulatory bodies in Canada, China, Finland, France, Germany, Japan, Sweden and USA, who conducted advanced studies and numerical modelling of coupled THMC processes under five tasks. This report summarizes the work contributed to Phase 2 of Task B of the project, which took place during the period of March 2004 to May 2006. The Phase 2 work incorporated the use of a wide range of numerical models to simulate the failure of a number of intact rock core samples, from the APSE tunnel at Aespoe HRL, as tested in uniaxial compression and other loading conditions with the intention of establishing the common and code-specific features of the models. The core samples of the Aespoe diorite were treated with different initial mechanical and chemical conditions as dry samples, saturated with distilled water, formation water and saline water, with different durations of submersion, respectively, in order to observe the mechanical effects of saturation by different chemical fluids on the mechanical properties of the intact core

  1. Photometric characterization of a well defined sample of isolated galaxies in the context of the AMIGA project

    CERN Document Server

    Durbala, A; Buta, R; Verdes-Montenegro, L

    2008-01-01

    We perform a detailed photometric analysis (bulge-disk-bar decomposition and Concentration-Asymmetry-Clumpiness - CAS parametrization) for a well defined sample of isolated galaxies, extracted from the Catalog of Isolated Galaxies (Karachentseva 1973) and reevaluated morphologically in the context of the AMIGA project. We focus on Sb-Sc morphological types, as they are the most representative population among the isolated spiral galaxies. Assuming that the bulge Sersic index and/or Bulge/Total luminosity ratios are reasonable diagnostics for pseudo- versus classical bulges, we conclude that the majority of late-type isolated disk galaxies likely host pseudobulges rather than classical bulges. Our parametrization of galactic bulges and disks suggests that the properties of the pseudobulges are strongly connected to those of the disks. This may indicate that pseudobulges are formed through internal processes within the disks (i.e. secular evolution) and that bars may play an important role in their formation. A...

  2. Análise qualitativa de compostos voláteis do headspace de carne cozida de ovinos e caprinos

    Directory of Open Access Journals (Sweden)

    Jossiê Zamperetti Donadel

    2013-11-01

    Full Text Available Este estudo teve como objetivo caracterizar qualitativamente os compostos voláteis (CV do headspace de diferentes músculos de carne cozida de ovinos e caprinos da região do Alto Camaquã, Rio Grande do Sul - Brasil. Os CV do headspace dos músculos cozidos, L. dorsi e V. lateralis de cinco ovinos machos (idade de 6 meses e cinco cabritos machos castrados (idade de 8-9 meses foram analisados pela técnica de microextração em fase sólida (HS-SPME e cromatógrafo a gás acoplado a espectrômetro de massas (GC/MS. Foram encontrados 73 compostos voláteis, dentre eles aldeídos, cetonas e compostos sulfurados, característicos de carne processada termicamente. A partir da fração volátil, foi possível encontrar marcadores que discriminassem as espécies animais estudadas, caracterizando os caprinos por apresentarem, entre outros compostos, terpenos (β-pineno, α-gurjuneno, α-muuroleno, ausentes em ovinos. Alguns compostos discriminaram V. lateralis e L. dorsi de ovinos, como álcool isopropílico, α-pineno, o-xileno, porém não foi possível obter uma diferenciação entre os músculos de caprinos.

  3. Detection and identification of volatile substances by headspace capillary gas chromatography to aid the diagnosis of acute poisoning.

    Science.gov (United States)

    Streete, P J; Ruprah, M; Ramsey, J D; Flanagan, R J

    1992-07-01

    Headspace gas chromatography with split flame-ionization-electron-capture detection is a simple method of screening for a wide range of volatile substances in biological fluids. A 60 m x 0.53 mm i.d. thick-film (5 microns) fused-silica capillary coated with SPB-1 (Supelchem) with split flame-ionization-electron-capture detection provides a valuable alternative to packed columns in this work. Most commonly abused compounds, including many with very low boiling-points such as bromochlorodifluoromethane (BCF), butane, dimethyl ether, FC 11, FC 12, isobutane and propane, can be retained and differentiated at an initial column temperature of 40 degrees C followed by programming to 200 degrees C. The total analysis time is 26 min. Retention and detector response data were generated for 244 compounds. Good peak shapes are obtained for polar analytes such as ethanol and injections of up to 0.30 cm3 of headspace can be performed with no discernable loss of efficiency. The sensitivity is thus at least as good as that attainable with packed columns. Of the commonly encountered compounds, only isobutane-methanol and paraldehyde-toluene are at all difficult to differentiate. Quantitative measurements can be performed either isothermally or by using the temperature programme.

  4. [Headspace GC/MS analysis of residual vinyl chloride and vinylidene chloride in polyvinyl chloride and polyvinylidene chloride products].

    Science.gov (United States)

    Ohno, Hiroyuki; Mutsuga, Motoh; Kawamura, Yoko; Suzuki, Masako; Aoyama, Taiki

    2005-02-01

    A headspace GC/MS analysis method for the simultaneous determination of residual vinyl chloride (VC) and vinylidene chloride (VDC) in polyvinyl chloride (PVC) and polyvinylidene chloride (PVDC) products was developed. A test sample was swelled overnight with N,N-dimethylacetamide in a sealed vial. The vial was incubated for 1 hour at 90 degrees C, then the headspace gas was analyzed by GC/MS using a PLOT capillary column. The recoveries from spiked PVC and PVDC samples were 90.0-112.3% for VC and 85.2-108.3% for VDC. The determination limits were 0.01 microg/g for VC and 0.06/microg/g for VDC, respectively. By this method, VC was detected in two PVC water supply pipes at the levels of 0.61 and 0.01 microg/g. On the other hand, VC and VDC were not detected in any of the food container-packages or toys tested.

  5. Static headspace-gas chromatography-mass spectrometry for the simultaneous determination of trihalomethanes and haloacetic acids in canned vegetables.

    Science.gov (United States)

    Cardador, Maria Jose; Gallego, Mercedes

    2016-07-08

    Canned vegetables appear to be a possible exposure pathway for hazardous disinfection by-products due to the use of sanitizers and treated water by the canning industry in the preparation of these foods. This work reports on two static headspace-gas chromatography-mass spectrometry methods for the simultaneous determination of 10 trihalomethanes (THMs) and 13 haloacetic acids (HAAs) in both solid and liquid phases of the canned vegetables. Both methods carry out the whole process (including the leaching of target analytes from the vegetable), derivatization of HAAs and volatilization of THMs and HAA esters, in a single step within a static headspace unit. The methods proposed provide an efficient and simple tool for the determination of regulated disinfection by-products in canned vegetables. Average limits of detection for THMs and HAAs were 0.19 and 0.45μg/kg, respectively, in the solid phase of canned vegetables, and 0.05 and 0.09μg/L, respectively, in the liquid phase. Satisfactory recoveries (90-99%) and precision, calculated as relative standard deviations (RSD≤10%), were obtained in both phases of canned vegetables. The methods proposed were applied for the analysis of frequently-used canned vegetables and confirmed the presence of up to 3 THMs and 5 HAAs at microgram per kilogram or liter levels in both phases of the samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. A novel method for rapid determination of total solid content in viscous liquids by multiple headspace extraction gas chromatography.

    Science.gov (United States)

    Xin, Li-Ping; Chai, Xin-Sheng; Hu, Hui-Chao; Barnes, Donald G

    2014-09-05

    This work demonstrates a novel method for rapid determination of total solid content in viscous liquid (polymer-enriched) samples. The method is based multiple headspace extraction gas chromatography (MHE-GC) on a headspace vial at a temperature above boiling point of water. Thus, the trend of water loss from the tested liquid due to evaporation can be followed. With the limited MHE-GC testing (e.g., 5 extractions) and a one-point calibration procedure (i.e., recording the weight difference before and after analysis), the total amount of water in the sample can be determined, from which the total solid contents in the liquid can be calculated. A number of black liquors were analyzed by the new method which yielded results that closely matched those of the reference method; i.e., the results of these two methods differed by no more than 2.3%. Compared with the reference method, the MHE-GC method is much simpler and more practical. Therefore, it is suitable for the rapid determination of the solid content in many polymer-containing liquid samples.

  7. Determination of arsenic and selenium by hydride generation and headspace solid phase microextraction coupled with optical emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Tyburska, Anna; Jankowski, Krzysztof, E-mail: kj@ch.pw.edu.pl; Rodzik, Agnieszka

    2011-07-15

    A hydride generation headspace solid phase microextraction technique has been developed in combination with optical emission spectrometry for determination of total arsenic and selenium. Hydrides were generated in a 10 mL volume septum-sealed vial and subsequently collected onto a polydimethylsiloxane/Carboxen solid phase microextraction fiber from the headspace of sample solution. After completion of the sorption, the fiber was transferred into a thermal desorption unit and the analytes were vaporized and directly introduced into argon inductively coupled plasma or helium microwave induced plasma radiation source. Experimental conditions of hydride formation reaction as well as sorption and desorption of analytes have been optimized showing the significant effect of the type of the solid phase microextraction fiber coating, the sorption time and hydrochloric acid concentration of the sample solution on analytical characteristics of the method developed. The limits of detection of arsenic and selenium were 0.1 and 0.8 ng mL{sup -1}, respectively. The limit of detection of selenium could be improved further using biosorption with baker's yeast Saccharomyces cerevisiae for analyte preconcentration. The technique was applied for the determination of total As and Se in real samples.

  8. Multi-Component Profiling of Trace Volatiles in Blood by Gas Chromatography/Mass Spectrometry with Dynamic Headspace Extraction.

    Science.gov (United States)

    Kakuta, Shoji; Yamashita, Toshiyuki; Nishiumi, Shin; Yoshida, Masaru; Fukusaki, Eiichiro; Bamba, Takeshi

    2015-01-01

    A dynamic headspace extraction method (DHS) with high-pressure injection is described. This dynamic extraction method has superior sensitivity to solid phase micro extraction, SPME and is capable of extracting the entire gas phase by purging the headspace of a vial. Optimization of the DHS parameters resulted in a highly sensitive volatile profiling system with the ability to detect various volatile components including alcohols at nanogram levels. The average LOD for a standard volatile mixture was 0.50 ng mL(-1), and the average LOD for alcohols was 0.66 ng mL(-1). This method was used for the analysis of volatile components from biological samples and compared with acute and chronic inflammation models. The method permitted the identification of volatiles with the same profile pattern as in vitro oxidized lipid-derived volatiles. In addition, the concentration of alcohols and aldehydes from the acute inflammation model samples were significantly higher than that for the chronic inflammation model samples. The different profiles between these samples could also be identified by this method. Finally, it was possible to analyze alcohols and low-molecular-weight volatiles that are difficult to analyze by SPME in high sensitivity and to show volatile profiling based on multi-volatile simultaneous analysis.

  9. Volatile flavour constituent patterns of Terras Madeirenses red wines extracted by dynamic headspace solid-phase microextraction.

    Science.gov (United States)

    Perestrelo, Rosa; Caldeira, Michael; Rodrigues, Freddy; Câmara, José S

    2008-06-01

    A suitable analytical procedure based on static headspace solid-phase microextraction (SPME) followed by thermal desorption gas chromatography-ion trap mass spectrometry detection (GC-(ITD)MS), was developed and applied for the qualitative and semi-quantitative analysis of volatile components of Portuguese Terras Madeirenses red wines. The headspace SPME method was optimised in terms of fibre coating, extraction time, and extraction temperature. The performance of three commercially available SPME fibres, viz. 100 mum polydimethylsiloxane; 85 mum polyacrylate, PA; and 50/30 mum divinylbenzene/carboxen on polydimethylsiloxane, was evaluated and compared. The highest amounts extracted, in terms of the maximum signal recorded for the total volatile composition, were obtained with a PA coating fibre at 30 degrees C during an extraction time of 60 min with a constant stirring at 750 rpm, after saturation of the sample with NaCl (30%, w/v). More than sixty volatile compounds, belonging to different biosynthetic pathways, have been identified, including fatty acid ethyl esters, higher alcohols, fatty acids, higher alcohol acetates, isoamyl esters, carbonyl compounds, and monoterpenols/C(13)-norisoprenoids.

  10. Optimization of extraction of apple aroma by dynamic headspace and influence of saliva on extraction of volatiles.

    Science.gov (United States)

    Mehinagic, Emira; Prost, Carole; Demaimay, Michel

    2004-08-11

    The dynamic headspace procedure of aroma extraction was optimized on Gala apples (Malus domestica). Two parameters affecting the extractability of compounds were studied: temperature and purge time. The influence of artificial saliva was also included. An increase in purge time and temperature caused an increase in the extraction of volatiles from the apple matrix. The optimum point of extraction was 40 degrees C and 70 min of purge. The study also showed that the addition of saliva influenced the extraction of volatile compounds, but this effect was different from one compound to another. To verify that the headspace extracts presented a global odor representativeness of fresh apple under these conditions of extraction, eight assessors compared the odor of extracts with fresh fruit odor for three different cultivars. With regard to the sensory profiles of extracts, the optimal conditions of extraction were suitable for extraction of volatile compounds, even if cooked apple odor appeared in some extracts. The similarity marks of extracts were low but acceptable.

  11. [Analysis of the components of floral scent in Glochidion puberum using gas chromatography-mass spectrometry with dynamic headspace adsorption].

    Science.gov (United States)

    Huang, Daihong; Zhang, Zhenguo; Chen, Guoping; Li, Houhun; Shi, Fuchen

    2015-03-01

    The floral scent plays the important key role in maintaining the obligate pollination mutualism between Glochidion plants and Epicephala moths. In the study, the dynamic headspace adsorption technique was employed to collect the floral scent emitted by Glochidion puberum, gas chromatography coupled with mass spectrometry (GC-MS) was used for the detection and identification of volatile chemical components in headspace samples of flowers from G. puberum. The peak area normalization was used to determine the relative contents of each odour component. The results showed that 45 compounds mainly consisting of monoterpenes and sesquiterpenes were isolated from the floral scent produced by G. puberum. Especially, both linalool (38.06%) and β-elemene (23.84%) were considered as the major scent components of G. puberum. It was speculated that linalool and β-elemene may be the two potential compounds attracting female Epicephala moths. The study provided the basic data for further electroantennographic detection and bioassays to identify the compounds having the actual physiological activity to female Epicephala moths.

  12. Changes of headspace volatile constituents of palm olein and selected oils after frying French fries.

    Science.gov (United States)

    Omar, Muhammad Nor Bin; Nor, Nor Nazuha M; Idris, Nor Aini

    2007-04-01

    Changes of aroma constituents of palm olein and selected oils after frying French fries have been studied. The aroma constituents of used oils were collected using a solid-phase microextraction (SPME) headspace technique with an absorbent of a divinylbenzene/carboxen (DVB/CAR) (50/30 microm) on polydimethylsiloxane (PDMS) fibre. The extracted volatiles were desorbed from the fibre in the injection port of the gas chromatograph at 250 degrees C and the aroma constituents were identified by GC-MS. Analytical data showed that volatile constituents of palm olein, soybean oil, corn oil and sunflower oil changed while frying continued from 2 to 40 h, respectively. In palm olein, the 2t,4t-decadienal content decreased from 14.7 to 5.5 microg g(-1) (40 h) whilst hexanal increased from 7.9 microg g(-1) (2 h) to 29.2 microg g(-1) (40 h), respectively. Similar result was also obtained from soybean oil after frying French fries. The 2t,4t-decadienal content decreased from 15.9 microg g(-1) (2 h) to 3.2 microg g(-1) after 40 h frying whilst hexanal increased from 10.2 microg g(-1) (2 h) to 34.2 microg g(-1) (40 h). Meanwhile, in corn oil, it was found that 2t,4t-decadienal decreased from 15.6 microg g(-1) (2 h) to 3.2 microg g(-1) (40 h) whilst hexanal increased from 11.3 microg g(-1) (2 h) to 33.8 microg g(-1) when frying time reached 40 h. In sunflower oil, it was found that 2t,4t-decadienal, decreased from 16.8 microg g(-1) (2 h) to 1.2 microg g(-1) (40 h) while hexanal increased from 9.5 microg g(-1) (2 h) to 32.4 microg g(-1) when frying time reached 40 h. It also showed that used oils exhibited off-odour characteristics due to the increasing amount ofhexanal while their freshness characteristics diminished due to the decreasing amount of 2t, 4t-decadienal.

  13. Vacuum-assisted headspace solid phase microextraction of polycyclic aromatic hydrocarbons in solid samples.

    Science.gov (United States)

    Yiantzi, Evangelia; Kalogerakis, Nicolas; Psillakis, Elefteria

    2015-08-26

    For the first time, Vacuum Assisted Headspace Solid Phase Microextraction (Vac-HSSPME) is used for the recovery of polycyclic aromatic hydrocarbons (PAHs) from solid matrices. The procedure was investigated both theoretically and experimentally. According to the theory, reducing the total pressure increases the vapor flux of chemicals at the soil surface, and hence improves HSSPME extraction kinetics. Vac-HSSPME sampling could be further enhanced by adding water as a modifier and creating a slurry mixture. For these soil-water mixtures, reduced pressure conditions may increase the volatilization rates of compounds with a low K(H) present in the aqueous phase of the slurry mixture and result in a faster HSSPME extraction process. Nevertheless, analyte desorption from soil to water may become a rate-limiting step when significant depletion of the aqueous analyte concentration takes place during Vac-HSSPME. Sand samples spiked with PAHs were used as simple solid matrices and the effect of different experimental parameters was investigated (extraction temperature, modifiers and extraction time). Vac-HSSPME sampling of dry spiked sand samples provided the first experimental evidence of the positive combined effect of reduced pressure and temperature on HSSPME. Although adding 2 mL of water as a modifier improved Vac-HSSPME, humidity decreased the amount of naphthalene extracted at equilibrium as well as impaired extraction of all analytes at elevated sampling temperatures. Within short HSSPME sampling times and under mild sampling temperatures, Vac-HSSPME yielded linear calibration curves in the range of 1-400 ng g(-1) and, with the exception of fluorene, regression coefficients were found higher than 0.99. The limits of detection for spiked sand samples ranged from 0.003 to 0.233 ng g(-1) and repeatability from 4.3 to 10 %. Finally, the amount of PAHs extracted from spiked soil samples was smaller compared to spiked sand samples, confirming that soil could bind target

  14. Characterization, performance modeling, and design of an active capping remediation project in a heavily polluted urban channel.

    Science.gov (United States)

    Yin, Ke; Viana, Priscilla; Zhao, Xiuhong; Rockne, Karl

    2010-07-15

    Collateral Channel is a heavily polluted former navigation slip to the Chicago Sanitary and Ship Canal (Illinois, USA). Characterization of sediment cores taken in the channel show high levels of heavy metals, polycyclic aromatic hydrocarbons (PAHs) and other contaminants in deposited sediment dating back to the 1800's. Of these, PAHs were the contaminants of greatest concern based upon exceedance of sediment contamination criteria (Sigma(16) PAHs up to 1500mg/kg). Benthic animal counts revealed a lack of biodiversity, with relatively low levels of small tubificid oligochaetes (generally work (Viana et al., 2008). Based on the sediment characterization and modeling results, the active capping design will be focused on organic contaminant sequestration through the use of organoclay. A site-specific difficulty is the substantial rates of gas ebullition from anaerobic organic matter biodegradation in the sediments, particularly in the summer months. These gases can open advective channels that may result in substantial pollution release and compromise cap effectiveness, and thus the capping scenario must control for such releases. The active capping layer will underlay a sloped sand layer and a high permeability gas venting system to allow biogenically-produced gas migration to shoreline collectors through an innovative support grid. The cap will include an overlaying wetland to remove nutrients from the adjoining Chicago River and provide a public recreational space.

  15. Preparation and Characterization of a Master Blend of Plutonium Oxide for the 3013 Large Scale Shelf-Life Surveillance Project

    Energy Technology Data Exchange (ETDEWEB)

    Gillispie, Obie William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Worl, Laura Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Veirs, Douglas Kirk [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stroud, Mary Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Narlesky, Joshua Edward [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Berg, John M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kelly, Elizabeth J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Padilla, Dennis D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bender, Beverly [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lopez, Annabelle S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Martinex, Max A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Trujillo, Leonardo A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wilson, Edward L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-04-10

    A mixture of chlorine-containing, impure plutonium oxides has been produced and has been given the name Master Blend. This large quantity of well-characterized chlorinecontaining material is available for use in the Integrated Surveillance and Monitoring Program for shelf-life experiments. It is intended to be representative of materials packaged to meet DOE-STD-3013.1 The Master Blend contains a mixture of items produced in Los Alamos National Laboratory’s (LANL) electro-refining pyrochemical process in the late 1990s. Twenty items were crushed and sieved, calcined to 800ºC for four hours, and blended multiple times. This process resulted in four batches of Master Blend. Calorimetry and density data on material from the four batches indicate homogeneity.

  16. The Urbis Project: Identification and Characterization of Potential Urban Development Areas as a Web-Based Service

    Science.gov (United States)

    Manzke, Nina; Kada, Martin; Kastler, Thomas; Xu, Shaojuan; de Lange, Norbert; Ehlers, Manfred

    2016-06-01

    Urban sprawl and the related landscape fragmentation is a Europe-wide challenge in the context of sustainable urban planning. The URBan land recycling Information services for Sustainable cities (URBIS) project aims for the development, implementation, and validation of web-based information services for urban vacant land in European functional urban areas in order to provide end-users with site specific characteristics and to facilitate the identification and evaluation of potential development areas. The URBIS services are developed based on open geospatial data. In particular, the Copernicus Urban Atlas thematic layers serve as the main data source for an initial inventory of sites. In combination with remotely sensed data like SPOT5 images and ancillary datasets like OpenStreetMap, detailed site specific information is extracted. Services are defined for three main categories: i) baseline services, which comprise an initial inventory and typology of urban land, ii) update services, which provide a regular inventory update as well as an analysis of urban land use dynamics and changes, and iii) thematic services, which deliver specific information tailored to end-users' needs.

  17. Initial field testing definition of subsurface sealing and backfilling tests in unsaturated tuff; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, J.A. [Sandia National Labs., Albuquerque, NM (United States); Case, J.B.; Tyburski, J.R. [I. T. Corp., Albuquerque, NM (United States)

    1993-05-01

    This report contains an initial definition of the field tests proposed for the Yucca Mountain Project repository sealing program. The tests are intended to resolve various performance and emplacement concerns. Examples of concerns to be addressed include achieving selected hydrologic and structural requirements for seals, removing portions of the shaft liner, excavating keyways, emplacing cementitious and earthen seals, reducing the impact of fines on the hydraulic conductivity of fractures, efficient grouting of fracture zones, sealing of exploratory boreholes, and controlling the flow of water by using engineered designs. Ten discrete tests are proposed to address these and other concerns. These tests are divided into two groups: Seal component tests and performance confirmation tests. The seal component tests are thorough small-scale in situ tests, the intermediate-scale borehole seal tests, the fracture grouting tests, the surface backfill tests, and the grouted rock mass tests. The seal system tests are the seepage control tests, the backfill tests, the bulkhead test in the Calico Hills unit, the large-scale shaft seal and shaft fill tests, and the remote borehole sealing tests. The tests are proposed to be performed in six discrete areas, including welded and non-welded environments, primarily located outside the potential repository area. The final selection of sealing tests will depend on the nature of the geologic and hydrologic conditions encountered during the development of the Exploratory Studies Facility and detailed numerical analyses. Tests are likely to be performed both before and after License Application.

  18. Experiment plan for characterization of the properties of molten rock at atmospheric and elevated pressures: Magma Energy Research Project

    Energy Technology Data Exchange (ETDEWEB)

    Modreski, P.J.

    1979-02-01

    Knowledge of the properties of molten rock (magma) is of importance to the Magma Energy Research Project of Sandia Laboratories. Facilities have been set up at Sandia to study the physical properties, chemistry, and corrosive nature of magma to 1600/sup 0/C and from atmospheric pressure to 4 kbar (400 MPa). Experiments at atmospheric pressure are being done in the presence of multicomponent gas mixtures to control the chemical activities of oxygen and sulfur. The high-pressure apparatus includes cold-seal small-volume pressure vessels (to 1100/sup 0/C and 1 kbar) and a large (750 cm/sup 3/ sample volume), internally heated pressure vessel (to 1600/sup 0/C and 4 kbar). The large vessel contains a number of penetrations for electrical leads and pressure lines, and is linked to a computer for data acquisition and control of experiments. Water and other dissolved volatiles (CO/sub 2/, CO, SO/sub 2/, S/sub 2/, H/sub 2/S, HCl, HF) have significant effects on all the properties of magma, and these effects will be studied in the high-pressure apparatus. Phase equilibria, viscosity, electrical conductivity, and materials compatibility will be the first properties to be examined under pressure. This report includes a review of the nature and chemical basis for the effects of dissolved volatiles on these properties of magma. 70 references, 10 figures.

  19. Got a Match? Ion Extraction GC-MS Characterization of Accelerants Adsorbed in Charcoal Using Negative Pressure Dynamic Headspace Concentration

    Science.gov (United States)

    Anzivino, Barbara; Tilley, Leon J.; Ingalls, Laura R.; Hall, Adam B.; Drugan, John E.

    2009-01-01

    An undergraduate organic chemistry experiment demonstrating real-life application of GC-MS to arson accelerant identification is described. Students are given the task of comparing a sample recovered from a "crime scene" to that from a "suspect's clothing". Accelerants subjected to different conditions are recovered using a quick and simple…

  20. Predictions of tracer transport in interwell tracer tests at the C-Hole complex. Yucca Mountain site characterization project report milestone 4077

    Energy Technology Data Exchange (ETDEWEB)

    Reimus, P.W.

    1996-09-01

    This report presents predictions of tracer transport in interwell tracer tests that are to be conducted at the C-Hole complex at the Nevada Test Site on behalf of the Yucca Mountain Site Characterization Project. The predictions are used to make specific recommendations about the manner in which the tracer test should be conducted to best satisfy the needs of the Project. The objective of he tracer tests is to study flow and species transport under saturated conditions in the fractured tuffs near Yucca Mountain, Nevada, the site of a potential high-level nuclear waste repository. The potential repository will be located in the unsaturated zone within Yucca Mountain. The saturated zone beneath and around the mountain represents the final barrier to transport to the accessible environment that radionuclides will encounter if they breach the engineered barriers within the repository and the barriers to flow and transport provided by the unsaturated zone. Background information on the C-Holes is provided in Section 1.1, and the planned tracer testing program is discussed in Section 1.2.

  1. Computational and Experimental Characterization of the Mach 6 Facility Nozzle Flow for the Enhanced Injection and Mixing Project at NASA Langley Research Center

    Science.gov (United States)

    Drozda, Tomasz G.; Cabell, Karen F.; Passe, Bradley J.; Baurle, Robert A.

    2017-01-01

    Computational fluid dynamics analyses and experimental data are presented for the Mach 6 facility nozzle used in the Arc-Heated Scramjet Test Facility for the Enhanced Injection and Mixing Project (EIMP). This project, conducted at the NASA Langley Research Center, aims to investigate supersonic combustion ramjet (scramjet) fuel injection and mixing physics relevant to flight Mach numbers greater than 8. The EIMP experiments use a two-dimensional Mach 6 facility nozzle to provide the high-speed air simulating the combustor entrance flow of a scramjet engine. Of interest are the physical extent and the thermodynamic properties of the core flow at the nozzle exit plane. The detailed characterization of this flow is obtained from three-dimensional, viscous, Reynolds-averaged simulations. Thermodynamic nonequilibrium effects are also investigated. The simulations are compared with the available experimental data, which includes wall static pressures as well as in-stream static pressure, pitot pressure and total temperature obtained via in-stream probes positioned just downstream of the nozzle exit plane.

  2. Rate and peak concentrations of off-gas emissions in stored wood pellets--sensitivities to temperature, relative humidity, and headspace volume.

    Science.gov (United States)

    Kuang, Xingya; Shankar, Tumuluru Jaya; Bi, Xiaotao T; Lim, C Jim; Sokhansanj, Shahab; Melin, Staffan

    2009-11-01

    Wood pellets emit CO, CO(2), CH(4), and other volatiles during storage. Increased concentration of these gases in a sealed storage causes depletion of concentration of oxygen. The storage environment becomes toxic to those who operate in and around these storages. The objective of this study was to investigate the effects of temperature, moisture, and the relative size of storage headspace on emissions from wood pellets in an enclosed space. Twelve 10-l plastic containers were used to study the effects of headspace ratio (25, 50, and 75% of container volume) and temperatures (10-50 degrees C). Another eight containers were set in uncontrolled storage relative humidity (RH) and temperature. Concentrations of CO(2), CO, and CH(4) were measured by gas chromatography (GC). The results showed that emissions of CO(2), CO, and CH(4) from stored wood pellets are more sensitive to storage temperature than to RH and the relative volume of headspace. Higher peak emission factors are associated with higher temperatures. Increased headspace volume ratio increases peak off-gas emissions because of the availability of oxygen associated with pellet decomposition. Increased RH in the enclosed container increases the rate of off-gas emissions of CO(2), CO, and CH(4) and oxygen depletion.

  3. Quantification of liquid products from the electroreduction of CO2 and CO using static headspace-gas chromatography and nuclear magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Bertheussen, Erlend; Abghoui, Younes; Jovanov, Zarko P.

    2017-01-01

    Static headspace-gas chromatography (HS-GC) useful for ex-situ liquid product analysis. Could complement high-performance liquid chromatography and NMR spectroscopy. Particularly high sensitivity towards compounds with high vapor pressure. Detection limits below 0.5μM were shown for acetaldehyde ...

  4. The effect of surfactant on headspace single drop microextraction for the determination of some volatile aroma compounds in citronella grass and lemongrass leaves by gas chromatography

    Science.gov (United States)

    A rapid method for the determination of some volatile aromatic compounds (VACs), including citronellal, citronellol, neral, geranial, geraniol, and eugenol in citronella grass and lemongrass leaves, was developed using surfactant as a surface tension modifier while performing headspace single drop m...

  5. Effect of emulsion properties on release of esters under static headspace, in vivo, and artificial throat conditions in relation to sensory intensity

    NARCIS (Netherlands)

    Weel, K.G.C.; Boelrijk, A.E.M.; Burger, J.J.; Jacobs, M.A.; Gruppen, H.; Voragen, A.G.J.; Smit, G.

    2004-01-01

    The effects of oil content and droplet size distributions of dilute oil-in-water emulsions on release of four esters with different hydrophobicities were studied under in vivo, static headspace, and artificial throat conditions. The effect of oil content on orthonasal and retronasal perceived

  6. Background vapor from six ionic liquids and the partition coefficients and limits of detection for 10 different analytes in those ionic liquids measured using headspace gas chromatography.

    Science.gov (United States)

    Von Wald, Grant; Albers, David; Cortes, Hernan; McCabe, Terry

    2008-08-01

    The concentration and identity of the compounds detected in the vapor above six ionic liquids by headspace gas chromatography (HS-GC) at 100 degrees C are reported. In addition, the partition coefficients for 10 different compounds in these ionic liquids and limits of detection were measured. These results provide quantitative guidance for the application of ionic liquids for HS-GC.

  7. Effect of emulsion properties on release of esters under static headspace, in vivo, and artificial throat conditions in relation to sensory intensity

    NARCIS (Netherlands)

    Weel, K.G.C.; Boelrijk, A.E.M.; Burger, J.J.; Jacobs, M.A.; Gruppen, H.; Voragen, A.G.J.; Smit, G.

    2004-01-01

    The effects of oil content and droplet size distributions of dilute oil-in-water emulsions on release of four esters with different hydrophobicities were studied under in vivo, static headspace, and artificial throat conditions. The effect of oil content on orthonasal and retronasal perceived intens

  8. Characterization of flood and precipitation events in Southwestern Germany and stochastic simulation of extreme precipitation (Project FLORIS-SV)

    Science.gov (United States)

    Florian, Ehmele; Michael, Kunz

    2016-04-01

    Several major flood events occurred in Germany in the past 15-20 years especially in the eastern parts along the rivers Elbe and Danube. Examples include the major floods of 2002 and 2013 with an estimated loss of about 2 billion Euros each. The last major flood events in the State of Baden-Württemberg in southwest Germany occurred in the years 1978 and 1993/1994 along the rivers Rhine and Neckar with an estimated total loss of about 150 million Euros (converted) each. Flood hazard originates from a combination of different meteorological, hydrological and hydraulic processes. Currently there is no defined methodology available for evaluating and quantifying the flood hazard and related risk for larger areas or whole river catchments instead of single gauges. In order to estimate the probable maximum loss for higher return periods (e.g. 200 years, PML200), a stochastic model approach is designed since observational data are limited in time and space. In our approach, precipitation is linearly composed of three elements: background precipitation, orographically-induces precipitation, and a convectively-driven part. We use linear theory of orographic precipitation formation for the stochastic precipitation model (SPM), which is based on fundamental statistics of relevant atmospheric variables. For an adequate number of historic flood events, the corresponding atmospheric conditions and parameters are determined in order to calculate a probability density function (pdf) for each variable. This method involves all theoretically possible scenarios which may not have happened, yet. This work is part of the FLORIS-SV (FLOod RISk Sparkassen Versicherung) project and establishes the first step of a complete modelling chain of the flood risk. On the basis of the generated stochastic precipitation event set, hydrological and hydraulic simulations will be performed to estimate discharge and water level. The resulting stochastic flood event set will be used to quantify the

  9. The M 4 Core Project with HST - V. Characterizing the PSFs of WFC3/UVIS by focus★

    Science.gov (United States)

    Anderson, J.; Bedin, L. R.

    2017-09-01

    As part of the astrometric Hubble Space Telescope (HST) large program GO-12911, we conduct an in-depth study to characterize the point spread function (PSF) of the Uv-VISual channel of the Wide Field Camera 3 (WFC3), as a necessary step to achieve the astrometric goals of the program. We extracted a PSF from each of the 589 deep exposures taken through the F467M filter over the course of a year and find that the vast majority of the PSFs lie along a 1-D locus that stretches continuously from one side of focus, through optimal focus, to the other side of focus. We constructed a focus-diverse set of PSFs and find that with only five medium-bright stars in an exposure it is possible to pin down the focus level of that exposure. We show that the focus-optimized PSF does a considerably better job fitting stars than the average 'library' PSF, especially when the PSF is out of focus. The fluxes and positions are significantly improved over the 'library' PSF treatment. These results are beneficial for a much broader range of scientific applications than simply the program at hand, but the immediate use of these PSFs will enable us to search for astrometric wobble in the bright stars in the core of the globular cluster M 4, which would indicate a dark, high-mass companion, such as a white dwarf, neutron star or black hole.

  10. Projecting policy-relevant metrics to characterize changing ozone extremes over the US: Variations by region, season and scenario

    Science.gov (United States)

    Rieder, Harald E.; Fiore, Arlene M.; Correa, Gus; Clifton, Olivia; Horrowitz, Larry W.; Naik, Vaishali

    2015-04-01

    Nitrogen oxide (NOx) emission controls have led to improved air quality (particularly in the Eastern US) over the past two decades, but concerns have been raised that climate warming may offset some of these gains in the coming decades. Here we address these concerns by analyzing the effect of projected future changes of emissions and climate, in isolation and combination, on US surface ozone (O3) during the 21st century in an ensemble of simulations (3 members per scenario) performed with the GFDL chemistry-climate model CM3. We analyze two Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5. Under both scenarios, NOx emissions decrease by ~80% over North America by 2100. In additional 3-member ensemble simulations, termed RCP4.5_WMGG and RCP8.5_WMGG, well-mixed greenhouse gases follow the respective RCP but O3 and aerosol precursor emissions are held at 2005 levels. These simulations enable us to isolate the role of well-mixed greenhouse gas induced climate change from that of emission reductions. Another set of simulations, following RCP8.5 but with methane (CH4) held fixed at 2005 levels, termed RCP8.5_2005CH4, allows us to quantify the background influence of CH4 on O3. For each season, we examine changes in the surface O3 distribution over the US during the 21st century, calculating policy relevant statistics: days above the current national ambient air quality standard (NAAQS) of 75 ppb and other proposed future levels, as well as the probabilistic 1-year return levels for maximum daily 8-hour average ozone (MDA8 O3), within each model grid cell. Specifically, we analyze: (i) regional and seasonal changes in the frequency and return level of high O3 pollution events during the 21st century, as well as (ii) differences among the RCPs by the middle and end of the 21st century. We find that the response of surface O3 to changes in emissions and climate varies strongly, seasonally and spatially, with certain regions more prone to a 'climate

  11. The Salton Seismic Imaging Project: Tomographic characterization of a sediment-filled rift valley and adjacent ranges, southern California

    Science.gov (United States)

    Davenport, K.; Hole, J. A.; Stock, J. M.; Fuis, G. S.; Carrick, E.; Tikoff, B.

    2011-12-01

    The Salton Trough in Southern California represents the northernmost rift of the Gulf of California extensional system. Relative motion between the Pacific and North American plates is accommodated by continental rifting in step-over zones between the San Andreas, Imperial, and Cerro Prieto transform faults. Rapid sedimentation from the Colorado River has isolated the trough from the southern portion of the Gulf of California, progressively filling the subsiding rift basin. Based on data from previous seismic surveys, the pre-existing continent has ruptured completely, and a new ~22 km thick crust has been created entirely by sedimentation overlying rift-related magmatism. The MARGINS, EarthScope, and USGS-funded Salton Seismic Imaging Project (SSIP) was designed to investigate the nature of this new crust, the ongoing process of continental rifting, and associated earthquake hazards. SSIP, acquired in March 2011, comprises 7 lines of onshore seismic refraction / wide-angle reflection data, 2 lines of refraction / reflection data in the Salton Sea, and a line of broadband stations. This presentation focuses on the refraction / wide-angle reflection line across the Imperial Valley, extending ~220 km across California from Otay Mesa, near Tijuana, to the Colorado River. The data from this line includes seventeen 100-160 kg explosive shots and receivers at 100 m spacing across the Imperial Valley to constrain the structure of the Salton Trough rift basin, including the Imperial Fault. Eight larger shots (600-920 kg) at 20-35 km spacing and receivers at 200-500 m spacing extend the line across the Peninsular Ranges and the Chocolate Mountains. These data will contrast the structure of the rift to that of the surrounding crust and provide constraints on whole-crust and uppermost mantle structure. Preliminary work has included tomographic inversion of first-arrival travel times across the Valley, emphasizing a minimum-structure approach to create a velocity model of the

  12. Characterization of the relocated and dispersed fuel in the Halden reactor project LOCA tests based on gamma scan data

    Energy Technology Data Exchange (ETDEWEB)

    Brankov, Vladimir, E-mail: vladimir.brankov@psi.ch [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Khvostov, Grigori; Mikityuk, Konstantin [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Pautz, Andreas [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne (Switzerland); Wiesenack, Wolfgang [Institutt For Energiteknikk OECD Halden Reactor Project, P.O. Box 173, Halden 1751 (Norway)

    2016-04-15

    Highlights: • We propose method to estimate dispersed fuel based on gamma scan data. • Analysis to determine the origin of relocated and dispersed fuel in Halden LOCA tests. • Useful data is gathered for code validation. • Suggestions are discussed to improve the quality of gamma scan data at Halden. • Dispersed and relocated material is a mixture of fuel from pellet periphery and bulk. - Abstract: The on-going Loss-of-Coolant Accident (LOCA) test program at the OECD Halden Reactor Project (HRP) conducts in-house gamma scanning as standard post-irradiation examination (PIE) procedure on Light Water Reactor (LWR) fuel rods. One of the primary objectives of the program is to investigate fuel relocation into the balloon region and fuel dispersal through the cladding rupture opening after burst. A simple model called Gamma Transport Model was formulated for the purpose of interpretation of fuel relocation based on the gamma scan data. Fuel relocation may have a strong effect on the linear heat generation rate at the balloon due to, firstly, increase in linear fuel density, and secondly due to differences in burn-up and local heat generation rate at the periphery and bulk of the pellet. For this analysis, a pair of short-lived isotopes with very different fission product yields for {sup 235}U and {sup 239}Pu is selected from the gamma scan spectrum. The intention is to use the difference in the ratio of their concentrations in the balloon region to qualitatively make conclusion on the fuel relocation. As a separate outcome, the same analysis can be applied to the dispersed fuel region and to draw conclusion on its origin (pellet rim or bulk). The Gamma Transport Model is validated against a special (non-destructive) case from the Halden LOCA test program and then applied for the analysis of selected tests. In addition, a methodology is presented for estimation of the amount of dispersed fuel from the LOCA tests based on the gamma scan data. Currently, at

  13. Reflex Project: Using Model-Data Fusion to Characterize Confidence in Analyzes and Forecasts of Terrestrial C Dynamics

    Science.gov (United States)

    Fox, A. M.; Williams, M.; Richardson, A.; Cameron, D.; Gove, J. H.; Ricciuto, D. M.; Tomalleri, E.; Trudinger, C.; van Wijk, M.; Quaife, T.; Li, Z.

    2008-12-01

    The Regional Flux Estimation Experiment, REFLEX, is a model-data fusion inter-comparison project, aimed at comparing the strengths and weaknesses of various model-data fusion techniques for estimating carbon model parameters and predicting carbon fluxes and states. The key question addressed here is: what are the confidence intervals on (a) model parameters calibrated from eddy covariance (EC) and leaf area index (LAI) data and (b) on model analyses and predictions of net ecosystem C exchange (NEE) and carbon stocks? The experiment has an explicit focus on how different algorithms and protocols quantify the confidence intervals on parameter estimates and model forecasts, given the same model and data. Nine participants contributed results using Metropolis algorithms, Kalman filters and a genetic algorithm. Both observed daily NEE data from FluxNet sites and synthetic NEE data, generated by a model, were used to estimate the parameters and states of a simple C dynamics model. The results of the analyses supported the hypothesis that parameters linked to fast-response processes that mostly determine net ecosystem exchange of CO2 (NEE) were well constrained and well characterised. Parameters associated with turnover of wood and allocation to roots, only indirectly related to NEE, were poorly characterised. There was only weak agreement on estimations of uncertainty on NEE and its components, photosynthesis and ecosystem respiration, with some algorithms successfully locating the true values of these fluxes from synthetic experiments within relatively narrow 90% confidence intervals. This exercise has demonstrated that a range of techniques exist that can generate useful estimates of parameter probability density functions for C models from eddy covariance time series data. When these parameter PDFs are propagated to generate estimates of annual C fluxes there was a wide variation in size of the 90% confidence intervals. However, some algorithms were able to make

  14. Characterization of Saharan dust properties transported towards Europe in the frame of the FENNEC project: a case study

    Science.gov (United States)

    Marnas, F.; Chazette, P.; Flamant, C.; Royer, P.; Sodemman, H.; Derimian, Y.

    2012-04-01

    In the framework of the FENNEC experiment (6 to 30 June 2011) an effort has been dedicated to characterize Saharan dust plumes transported towards southern Europe. Hence, a multi instrumented field campaign has been conducted. Ground based nitrogen Raman LIDAR (GBNRL) has been deployed in southern Spain close to Marbella, simultaneously with airborne lidar (AL) performing measurements over both the tropical Atlantic Ocean and the western Africa (from 2 to 23 June). The GBNRL was equipped with co-polar and cross-polar channels to perform continuous measurements of the dust aerosols trapped in the troposphere. It was developed by LSCE with the support of the LEOSPHERE Company. The French FALCON 20 research aircraft operated by SAFIRE (Service des Avions Francais Instrumentés pour la Recherche en Environnement) carried the AL Leandre Nouvelle Generation (LNG) as well as a dropsonde releasing system and radiometers. A major, one week long, dust event has been sampled over Spain from 25 June to 1 July with high optical depth (>0.5 at 355nm) and particular depolarization ratios (15 to 25%). Backtrajectory studies suggest that the dust particles observed were from dust uplifts that occurred in Southern Morocco and Northern Mauritania. The event has been also documented 3 days before by the AL flying over Mauritania. AERONET sunphotometer measurements of aerosol properties, along the dust plume transport path appear to be coherent with both the lidar and the backtrajectory analysis. These analysis exhibit a likely major contribution from the Western Sahara sources to the Southern Europe. Such a contribution may impact the visibility and then the airtrafic, modify the tropospheric chemistry, and add nutrients to both the Mediterranean Sea and the continental surfaces. It can also affect the health of European populations. We will present strategy of the experiment and the case study built from measurements performed at the end of June.

  15. Electro-mechanical characterization of MgB2 wires for the Superconducting Link Project at CERN

    Science.gov (United States)

    Konstantopoulou, K.; Ballarino, A.; Gharib, A.; Stimac, A.; Garcia Gonzalez, M.; Perez Fontenla, A. T.; Sugano, M.

    2016-08-01

    In previous years, the R & D program between CERN and Columbus Superconductors SpA led to the development of several configurations of MgB2 wires. The aim was to achieve excellent superconducting properties in high-current MgB2 cables for the HL-LHC upgrade. In addition to good electrical performance, the superconductor shall have good mechanical strength in view of the stresses during operation (Lorenz forces and thermal contraction) and handling (tension and bending) during cabling and installation at room temperature. Thus, the study of the mechanical properties of MgB2 wires is crucial for the cable design and its functional use. In the present work we report on the electro-mechanical characterization of ex situ processed composite MgB2 wires. Tensile tests (critical current versus strain) were carried out at 4.2 K and in a 3 T external field by means of a purpose-built bespoke device to determine the irreversible strain limit of the wire. The minimum bending radius of the wire was calculated taking into account the dependence of the critical current with the strain and it was then used to obtain the minimum twist pitch of MgB2 wires in the cable. Strands extracted from cables having different configurations were tested to quantify the critical current degradation. The Young’s modulus of the composite wire was measured at room temperature. Finally, all measured mechanical parameters will be used to optimize an 18-strand MgB2 cable configuration.

  16. Geomorphic characterization of the Fortymile Wash alluvial fan, Nye County, Nevada, in support of the Yucca Mountain Project

    Science.gov (United States)

    Cline, M.; Delong, S.; Pelletier, J.

    2005-12-01

    In the event of an unlikely volcanic eruption through the proposed high-level radioactive waste repository at Yucca Mountain, contaminated ash may be deposited in portions of the Fortymile Wash drainage basin and subsequently redistributed to the Fortymile Wash alluvial fan by fluvial processes. Characterization of the Fortymile Wash alluvial fan has been undertaken as part of an effort to quantify the transport of contaminated ash throughout the fluvial system, especially to define the spatial distribution of fluvial activity over time scales of repository operation, and the rates of radionuclide migration into different soils on the fan. The Fortymile Wash alluvial fan consists of extremely low relief terraces as old as 70 ka. By conducting soils-geomorphic mapping and correlating relative surface ages with available geochronology from the Fortymile Wash fan and adjacent piedmonts, we identified 4 distinct surfaces on the fan. Surface ages are used to predict the relative stability of different areas of the fan to fluvial activity. Pleistocene-aged surfaces are assumed to be fluvially inactive over the 10 kyr time scale, for example. Our mapping and correlation provides a map of the depozone for contaminated ash that takes into account long-term channel migration for the time scales of repository operation, and it provides a geomorphic framework for predicting radionuclide dispersion rates into different soils across the fan. The standard model for vertical migration of radionuclides in soil is diffusion; therefore we used diffusion profiles derived from 137Cs fallout to determine radionuclide infiltration rates on the various geomorphic surfaces. The results show a strong inverse correlation of the geomorphic surface age and diffusivity values inferred from the 137Cs profiles collected on the different surfaces of the fan.

  17. Characterization of masses in digital breast tomosynthesis: Comparison of machine learning in projection views and reconstructed slices

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Heang-Ping; Wu Yita; Sahiner, Berkman; Wei, Jun; Helvie, Mark A.; Zhang Yiheng; Moore, Richard H.; Kopans, Daniel B.; Hadjiiski, Lubomir; Way, Ted [Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109 (United States); Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2010-07-15

    Purpose: In digital breast tomosynthesis (DBT), quasi-three-dimensional (3D) structural information is reconstructed from a small number of 2D projection view (PV) mammograms acquired over a limited angular range. The authors developed preliminary computer-aided diagnosis (CADx) methods for classification of malignant and benign masses and compared the effectiveness of analyzing lesion characteristics in the reconstructed DBT slices and in the PVs. Methods: A data set of MLO view DBT of 99 patients containing 107 masses (56 malignant and 51 benign) was collected at the Massachusetts General Hospital with IRB approval. The DBTs were obtained with a GE prototype system which acquired 11 PVs over a 50 deg. arc. The authors reconstructed the DBTs at 1 mm slice interval using a simultaneous algebraic reconstruction technique. The region of interest (ROI) containing the mass was marked by a radiologist in the DBT volume and the corresponding ROIs on the PVs were derived based on the imaging geometry. The subsequent processes were fully automated. For classification of masses using the DBT-slice approach, the mass on each slice was segmented by an active contour model initialized with adaptive k-means clustering. A spiculation likelihood map was generated by analysis of the gradient directions around the mass margin and spiculation features were extracted from the map. The rubber band straightening transform (RBST) was applied to a band of pixels around the segmented mass boundary. The RBST image was enhanced by Sobel filtering in the horizontal and vertical directions, from which run-length statistics texture features were extracted. Morphological features including those from the normalized radial length were designed to describe the mass shape. A feature space composed of the spiculation features, texture features, and morphological features extracted from the central slice alone and seven feature spaces obtained by averaging the corresponding features from three to 19

  18. Management system information of characterization of the dismantling project of Jose Cabrera; Sistema de Gestion de la informacion de caracterizacion del proyecto de desmantelamiento de la CN Jose Cabrera

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno Blesa, M. E.; Martin Palomo, N.; Gomez Rodriguez, C. A.

    2011-07-01

    In the proposed dismantling and decommissioning of the Jose Cabrera NPP is designed and implemented a database of physical and radiological inventory, which provides a powerful tool to optimize the storage, monitoring and control of the characterization data. The database is a useful and reliable management system characterization information that facilitates access and information processing, and ensures their integrity and traceability along of the dismantling project.

  19. Project 2010 Project Management

    CERN Document Server

    Happy, Robert

    2010-01-01

    The ideal on-the-job reference guide for project managers who use Microsoft Project 2010. This must-have guide to using Microsoft Project 2010 is written from a real project manager's perspective and is packed with information you can use on the job. The book explores using Project 2010 during phases of project management, reveals best practices, and walks you through project flow from planning through tracking to closure. This valuable book follows the processes defined in the PMBOK Guide, Fourth Edition , and also provides exam prep for Microsoft's MCTS: Project 2010 certification.: Explains

  20. Analysis of benzene, toluene, ethylbenzene and xylenes in soils by headspace and gas chromatography/flame ionization detector

    Directory of Open Access Journals (Sweden)

    Jurandir Pereira Pinto

    2006-02-01

    Full Text Available The constituents of gasoline: benzene, toluene, ethylbenzene and xylenes (BTEX are frequently found in soils due to leaks in fuel storage tanks and they present chronic toxicity. In this work it was developed and validated a methodology of BTEX analysis in soil by gas chromatography/ flame ionization detector and static headspace. The recovery of BTEX in soil samples was evaluated using soils with different textures (sandy and loamy. The analysis method showed good resolution, in a low time of analysis (less than 30 minutes. Limits of quantification of 0.05 mg Kg¯¹ soil for benzene, toluene, ethylbenzene and xylenes are below the guiding values that range from 0.15 to 95 mg Kg¯¹ soil, established to determine soil quality. It was verified that the methodology enables the use of this method for BTEX analysis of soil samples for passive environmental identification of gas stations.

  1. Determination of 1,3-dichloropropanol in soy sauces by automated headspace gas chromatography-mass spectrometry.

    Science.gov (United States)

    Crews, C; LeBrun, G; Brereton, P A

    2002-04-01

    There has been recent concern about the levels of carcinogenic chloropropanols in some soy sauces. We have devised and tested a new automated headspace GC-MS technique for the analysis of 1,3-dichloropropan-2-ol (1,3-DCP) in soy sauce and similar products. The method incorporates the use of cryogenic trapping and a deuterium-labelled internal standard. The limit of detection was 0.003 mg kg(-1). After in-house validation testing, the method was applied to soy sauce samples that had previously been analysed for the related contaminant 3-monochloropropanediol (3-MCPD). 1,3-DCP was detected in 10 of 40 sauces, all of which also contained 3-MCPD. The highest level was just >1 mg kg(-1). There was no correlation between the levels of 1,3-DCP and 3-MCPD.

  2. Comparison of two headspace sampling techniques for the analysis of off-flavour volatiles from oat based products.

    Science.gov (United States)

    Cognat, Claudine; Shepherd, Tom; Verrall, Susan R; Stewart, Derek

    2012-10-01

    Two different headspace sampling techniques were compared for analysis of aroma volatiles from freshly produced and aged plain oatcakes. Solid phase microextraction (SPME) using a Carboxen-Polydimethylsiloxane (PDMS) fibre and entrainment on Tenax TA within an adsorbent tube were used for collection of volatiles. The effects of variation in the sampling method were also considered using SPME. The data obtained using both techniques were processed by multivariate statistical analysis (PCA). Both techniques showed similar capacities to discriminate between the samples at different ages. Discrimination between fresh and rancid samples could be made on the basis of changes in the relative abundances of 14-15 of the constituents in the volatile profiles. A significant effect on the detection level of volatile compounds was observed when samples were crushed and analysed by SPME-GC-MS, in comparison to undisturbed product. The applicability and cost effectiveness of both methods were considered. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Determination of benzene in soft drinks and other beverages by isotope dilution headspace gas chromatography/mass spectrometry.

    Science.gov (United States)

    Cao, Xu-Liang; Casey, Valerie; Seaman, Steve; Tague, Brett; Becalski, Adam

    2007-01-01

    An automated, simple, and reproducible method was developed for the determination of benzene in soft drinks, based on isotope dilution headspace gas chromatography/mass spectrometry in the selected-ion monitoring mode. The method was used to assess benzene levels in samples of 124 soft drinks and beverages. Benzene was not detected in 60% of the 124 products. The average benzene levels in 6 products exceeded the Canadian maximum acceptable concentration of 5 microg/L for benzene in drinking water, and 2 of the 6 products had benzene levels above the World Health Organization guideline of 10 microg/L. The highest level of benzene, 23 microg/L, was found in a soft drink product specifically marketed to children.

  4. Determination of the solubility of low volatility liquid organic compounds in water using volatile-tracer assisted headspace gas chromatography.

    Science.gov (United States)

    Zhang, Shu-Xin; Chai, Xin-Sheng; Barnes, Donald G

    2016-02-26

    This study reports a new headspace gas chromatographic method (HS-GC) for the determination of water solubility of low volatility liquid organic compounds (LVLOs). The HS-GC analysis was performed on a set of aqueous solutions containing a range of concentrations of toluene-spiked (as a tracer) LVLOs, from under-saturation to over-saturation. A plot of the toluene tracer GC signal vs. the concentration of the LVLO results in two lines of different slopes that intersect at the concentration corresponding to the compound's solubility in water. The results showed that the HS-GC method has good precision (RSD solubility of LVLOs at elevated temperatures. This approach should be of special interest to those concerned about the impact of the presence of low-volatility organic liquids in waters of environmental and biological systems.

  5. Volatile constituents of Murraya koenigii fresh leaves using headspace solid phase microextraction--gas chromatography-mass spectrometry.

    Science.gov (United States)

    Sukkaew, Sayamol; Pripdeevech, Patcharee; Thongpoon, Chalermporn; Machan, Theeraphan; Wongchuphan, Rattana

    2014-12-01

    The volatile components of Murraya koenigii fresh leaves, collected from Surat Thani province, Thailand were studied by using headspace (HS) solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). The four fibers employed to extract the volatiles were polydimethylsiloxane (PDMS), polydimethylsiloxane-divinylbenzene (PDMS-DVB), carboxane-polydimethylsiloxane (CAR-PDMS) and polydimethylsiloxane-divinylbenzene-carboxane (PDMS-DVB-CAR). The volatile constituents of M. koenigii fresh leaves were also extracted by hydrodistillation and analyzed by GC-MS. Fifty-one compounds were identified by these fibers. Five major compounds, γ-terpinene, β-caryophyllene, β-phellandrene, a-selinene and a-pinene, were detected in all fibers. The PDMS-DVB-CAR fiber was considered as the best for trapping key volatiles of M. koenigii fresh leaves.

  6. Prediction of the wine sensory properties related to grape variety from dynamic-headspace gas chromatography-olfactometry data.

    Science.gov (United States)

    Campo, Eva; Ferreira, Vicente; Escudero, Ana; Cacho, Juan

    2005-07-13

    Wine extracts obtained by a dynamic headspace sampling technique were studied by quantitative gas chromatography-olfactometry (GC-O) to determine the aroma profiles of six young monovarietal Spanish white wines. A partial least-square regression study was carried out to look for models relating wine aroma properties with GC-O scores. Models were validated by sensory analysis. Four out of the five most important sensory descriptors were satisfactorily described by a model, and sensory tests confirmed most of the predictions. The main aroma differences between these wines are due to the ratio linalool/3-mercaptohexyl acetate. Floral, sweet, and muscat are positively related to the concentration of linalool and negatively to that of 3-mercaptohexyl acetate. Tropical fruit is related to the wine content in this last odorant. 2-Phenyl acetate, reinforced by other acetates, can also contribute to floral and sweet notes. Alkyl-methoxypyrazines lessen the tropical fruit note, and acetic acid lessens the muscat nuance.

  7. Quantitative determination of volatile organic compounds (VOC) in milk by multiple dynamic headspace extraction and GC-MS.

    Science.gov (United States)

    Ciccioli, Paolo; Brancaleoni, Enzo; Frattoni, Massimiliano; Fedele, Vincenzo; Claps, Salvatore; Signorelli, Federica

    2004-01-01

    A method for the accurate determination of volatile organic compounds (VOC) in milk samples has been developed and tested. It combines multiple dynamic headspace extraction with GC-MS. Absolute amounts of VOC in the liquid phase are obtained by determining the first order kinetic dependence of the stepwise extraction of the analytes and internal standards from the liquid matrix. Compounds released from milk were collected on a train of traps filled with different solid sorbents to cover all components having a number of carbon atoms ranging from 4 to 15. They were analysed by GC-MS after thermal desorption of VOC from the collecting traps. Quantification of VOC in milk was performed using deuterated compounds as internal standards. The method was used to follow seasonal variations of monoterpenes in goat milk and to detect the impact of air pollution on the quality of milk.

  8. Coupled extruder-headspace, a new method for analysis of the essential oil components of Coriandrum sativum fruits.

    Science.gov (United States)

    Sriti, Jazia; Msaada, Kamel; Talou, Thierry; Faye, Mamadou; Vilarem, Gerard; Marzouk, Brahim

    2012-10-15

    A new method involving concurrent single screw extruder combined with continuous headspace dynamic for the extraction and identification of the essential oil of Coriandrum sativum L. fruit was developed. The effect of six different nozzle diameters (5, 6, 7, 8, 9 and 10 mm) on the content and chemical composition of the essential oil of coriander fruit was studied. The oils from fruit samples were obtained by OMEGA 20 extruder. The result showed that the highest yield (0.53%) was obtained by the diameter of the nozzle was 8mm. Twenty-nine components were determined in essential oils, which were mostly hydrocarbons and alcohol monoterpenes. The main components linalool, α-pinene, γ-terpinene, p-cymene and limonene showed significant variations with drying trials.

  9. Semi-projective modules

    Directory of Open Access Journals (Sweden)

    D. Döman

    1984-03-01

    Full Text Available It is well-known that the submodules of a projective module need not be projective. In this article we investigate a certain projectivity which is preserved under the taking of submodules. This property is used to characterize hereditary rings and QF rings.

  10. [Study of volatile organic compounds of fresh allium species using headspace combined with surface-enhanced Raman scattering].

    Science.gov (United States)

    Si, Min-Zhen; Zhang, De-Qing; Liu, Ren-Ming

    2014-09-01

    In order to identify volatile organic compounds of fresh plants at room temperature and avoid sample pretreatment and extractions which can be labor intensive, garlic, Chinese chives and scallion were chopped into pieces. Then some of them were placed in the headspace vial and sealed. The gases were drawn from the vial with a syringe and were injected very slowly into Ag colloids for test using R-3000 portable Raman spectrometer. The spectra of volatile organic compounds of allium species, fresh garlic, Chinese chive and shallot plants were successfully.recorded for the first time. For garlic high intensity bands are present at 307, 399, 569, 711, 1,182, 1,287, 1,397 and 1,622 cm(-1). For Chinese chives the high intensity band is present at 672 cm(-1). Low intensity bands are present at 274, 412, 575, 1,185, 1,289, 1,396, 1,618 cm(-1). For shallot high intensity bands are present at 693 cm(-1). Lower intensity bands are present at 372, 888, 1,023 cm(-1). Low intensity bands are present at 1,088, 1,211 and 1,322 cm(-1). The SERS of diallyl disulfide, allyl methyl sulfide and 1-propanethiol in liquid state and gas state were also obtained. The main volatile organic compound of fresh garlic, Chinese chive and shallot are diallyl disulfide, allyl methyl sulfide and 1-propanethiol respectively, and the volatile organic compound of fresh onion, scallion, shallot and chive are all 1-propanethiol. The presented results illustrate that combining headspace and SERS is a powerful tool for volatile organic compound analysis in fresh plants. The volatile organic compound can be detected in fresh plant samples directly and quickly without extraction.

  11. Determination of Polybrominated Diphenyl Ethers in Water Samples by Headspace Solid-Phase Microextraction Technique with Carbon Nanotube Coated Fibers

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A headspace solid-phase microextraction (HS-SPME) method was developed for gas chromatography with electron-capture detection (GC-ECD) of polybrominated diphenyl ethers (PBDEs) in water samples. Silicon fibers coated with multiwalled carbon nanotube (MWCNT) with a 35 μm thickness were prepared for the SPME. Various parameters affecting the efficiency for the SPME of PBDEs, such as extraction time, temperature, agitation, volume of headspace, pH of sample, addition of salt and acetone were studied and optimized. The extraction efficiencies by HS-SPME and SPME at 25 and 100℃ were compared. At room temperature (ca. 25 ℃) the response obtained with SPME was 2-10 times higher than with HS-SPME. However, at 100℃ HS-SPME gave responses 1-8 times higher than SPME. The responses obtained with SPME and HS-SPME at 100℃ were higher than those at room temperature by a factor of 0.7-1.4 for SPME and by a factor of 2-40 for HS-SPME. The linear range of the developed method was 50-1600 ng/L with the linear correlation coefficients (r) ranging from 0.995 to 0.998. The limits of detection (S/N=3) for the five PBDEs were in the range of 1.1-16.0 ng/L and the precision (RSD, n=5) for peak area was 5.0%-9.1%. The developed method was successfully applied to the analysis of real water sam-ples with recovery of 74.2%-98.7%.

  12. Polytope projects

    CERN Document Server

    Iordache, Octavian

    2013-01-01

    How do you know what works and what doesn't? This book contains case studies highlighting the power of polytope projects for complex problem solving. Any sort of combinational problem characterized by a large variety of possibly complex constructions and deconstructions based on simple building blocks can be studied in a similar way. Although the majority of case studies are related to chemistry, the method is general and equally applicable to other fields for engineering or science.

  13. Comparison of different methods: static and dynamic headspace and solid-phase microextraction for the measurement of interactions between milk proteins and flavor compounds with an application to emulsions.

    Science.gov (United States)

    Fabre, M; Aubry, V; Guichard, E

    2002-03-13

    Interactions between 10 aroma compounds from different chemical classes and 5 mixtures of milk proteins have been studied using static or dynamic headspace gas chromatography and solid-phase microextraction (SPME). Static headspace analysis allows the quantification of the release of only the most abundant compounds. Dynamic headspace analysis does not allow the discrimination of flavor release from the different protein mixtures, probably due to a displacement of headspace equilibrium. By SPME analysis and quantification by GC-MS (SIM mode) all of the volatiles were quantified. This method was optimized to better discriminate aroma release from the different milk protein mixtures and then from oil/water emulsions made with these proteins. The highest difference between the release in different proteins was observed for ethyl hexanoate, which has a great affinity for beta-lactoglobulin. Ethyl hexanoate is thus less released from models and emulsions containing this protein.

  14. House dust fungal communities' characterization: a double take on the six by sixty by six (6 × 60 × 6) project

    Science.gov (United States)

    Amaro, Raquel; Coelho, Sónia D.; Pastorinho, M. Ramiro; Taborda-Barata, Luís; Vaz-Patto, Maria A.; Monteiro, Marisa; Nepomuceno, Miguel C. S.; Lanzinha, Joăo C. G.; Teixeira, Joăo P.; Pereira, Cristiana C.; Sousa, Ana C. A.

    2016-11-01

    Fungi are a group of microbes that are found with particular incidence in the indoor environment. Their direct toxicity or capability of generating toxic compounds has been associated with a large number of adverse health effects, such as infectious diseases and allergies. Given that in modern society people spend a large part of their time indoors; fungal communities' characterization of this environmental compartment assumes paramount importance in the comprehension of health effects. House dust is an easy to obtain, time-integrative matrix, being its use in epidemiological studies on human exposure to environmental contaminants highly recommended. Furthermore, dust can carry a great variety of fungal content that undergoes a large number of processes that modulate and further complexify human exposure. Our study aims to identify and quantify the fungal community on house dust samples collected using two different methodologies (an approach not often seen in the literature): active (vacuum cleaner bags) and passive sampling (dust settled in petri dishes). Sampling was performed as part of the ongoing 6 × 60 × 6 Project in which six houses from Covilhă (Portugal), with building dates representative of six decades, were studied for a period of sixty days.

  15. THE BNL ASTD FIELD LAB - NEAR - REAL - TIME CHARACTERIZATION OF BNL STOCKPILED SOILS TO ACCELERATE COMPLETION OF THE EM CHEMICAL HOLES PROJECT.

    Energy Technology Data Exchange (ETDEWEB)

    BOWERMAN,B.S.; ADAMS,J.W.; HEISER,J.; KALB,P.D.; LOCKWOOD,A.

    2003-04-01

    As of October 2001, approximately 7,000 yd{sup 3} of stockpiled soil remained at Brookhaven National Laboratory (BNL) after the remediation of the BNL Chemical/Animal/Glass Pits disposal area. The soils were originally contaminated with radioactive materials and heavy metals, depending on what materials had been interred in the pits, and how the pits were excavated. During the 1997 removal action, the more hazardous/radioactive materials were segregated, along with, chemical liquids and solids, animal carcasses, intact gas cylinders, and a large quantity of metal and glass debris. Nearly all of these materials have been disposed of. In order to ensure that all debris was removed and to characterize the large quantity of heterogeneous soil, BNL initiated an extended sorting, segregation, and characterization project directed at the remaining soil stockpiles. The project was co-funded by the Department of Energy Environmental Management Office (DOE EM) through the BNL Environmental Restoration program and through the DOE EM Office of Science and Technology Accelerated Site Technology Deployment (ASTD) program. The focus was to remove any non-conforming items, and to assure that mercury and radioactive contaminant levels were within acceptable limits for disposal as low-level radioactive waste. Soils with mercury concentrations above allowable levels would be separated for disposal as mixed waste. Sorting and segregation were conducted simultaneously. Large stockpiles (ranging from 150 to 1,200 yd{sup 3}) were subdivided into manageable 20 yd{sup 3} units after powered vibratory screening. The 1/2-inch screen removed almost all non-conforming items (plus some gravel). Non-conforming items were separated for further characterization. Soil that passed through the screen was also visually inspected before being moved to a 20 yd{sup 3} ''subpile.'' Eight samples from each subpile were collected after establishing a grid of four quadrants: north, east

  16. Headspace solid-phase microextraction-gas chromatographic-time-of-flight mass spectrometric methodology for geographical origin verification of coffee.

    Science.gov (United States)

    Risticevic, Sanja; Carasek, Eduardo; Pawliszyn, Janusz

    2008-06-09

    Increasing consumer awareness of food safety issues requires the development of highly sophisticated techniques for the authentication of food commodities. The food products targeted for falsification are either products of high commercial value or those produced in large quantities. For this reason, the present investigation is directed towards the characterization of coffee samples according to the geographical origin. The conducted research involves the development of a rapid headspace solid-phase microextraction (HS-SPME)-gas chromatography-time-of-flight mass spectrometry (GC-TOFMS) method that is utilized for the verification of geographical origin traceability of coffee samples. As opposed to the utilization of traditional univariate optimization methods, the current study employs the application of multivariate experimental designs to the optimization of extraction-influencing parameters. Hence, the two-level full factorial first-order design aided in the identification of two influential variables: extraction time and sample temperature. The optimum set of conditions for the two variables was 12 min and 55 degrees C, respectively, as directed by utilization of Doehlert matrix and response surface methodology. The high-throughput automated SPME procedure was completed by implementing a single divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) 50/30 microm metal fiber with excellent durability properties ensuring the completion of overall sequence of coffee samples. The utilization of high-speed TOFMS instrument ensured the completion of one GC-MS run of a complex coffee sample in 7.9 min and the complete list of benefits provided by ChromaTOF software including fully automated background subtraction, baseline correction, peak find and mass spectral deconvolution algorithms was exploited during the data evaluation procedure. The combination of the retention index (RI) system using C(8)-C(40) alkanes and the mass spectral library search was utilized

  17. Estimation of the impact of water movement from sewage and settling ponds near a potential high level radioactive waste repository in Yucca Mountain, Nevada; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Sobolik, S.R.; Fewell, M.E.

    1992-02-01

    The Yucca Mountain Site Characterization Project is studying Yucca Mountain in southwestern Nevada as a potential site for a high-level nuclear waste repository. Site characterization includes surface-based and underground testing. Analyses have been performed to design site characterization activities with minimal impact on the ability of the site to isolate waste, and on tests performed as part of the characterization process. One activity of site characterization is the construction of an Exploratory Studies Facility, which may include underground shafts, drifts, and ramps, and the accompanying ponds used for the storage of sewage water and muck water removed from construction operations. The information in this report pertains to the two-dimensional numerical calculations modelling the movement of sewage and settling pond water, and the potential effects of that water on repository performance and underground experiments. This document contains information that has been used in preparing Appendix I of the Exploratory Studies Facility Design Requirements document (ESF DR) for the Yucca Mountain Site Characterization Project.

  18. Microwave distillation followed by headspace single drop microextraction coupled to gas chromatography-mass spectrometry (GC-MS) for fast analysis of volatile components of Echinophora platyloba DC.

    Science.gov (United States)

    Gholivand, Mohammad Bagher; Abolghasemi, Mir Mahdi; Piryaei, Marzieh; Maassoumi, Sayed Mohammad; Papzan, Abdolhamid

    2013-05-01

    To avoid the traditional and time consuming hydrodistillation, the analyses of volatile components in aerial parts of Echinophora platyloba DC was carried out by a simple microwave distillation followed by headspace single drop microextraction (MD-HS-SDME) coupled to gas chromatography-mass spectrometry (GC-MS). The headspace volatile compounds were collected after irradiation using a single drop of n-heptadecan. The extraction conditions were optimised using the relative peak areas as index. The chemical composition of the MD-HS-SDME extracts was confirmed according to their retention indexes and mass spectra. Fifty-three components were extracted and identified by using the MD-HS-SDME method. E-β-ocimene (53.81%), R-D-decalactone (12.75%), α-pinene (6.43%), n-heptanol (6.27%), β-phellanderne (2.70%) and linalool (1.89%) were the major constituents. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Flash Evaporation and Headspace Solid-phase Microextraction for the Analysis of the Essential Oils in Traditional Chinese Medicine, Houttuynia Cordata Thunb

    Institute of Scientific and Technical Information of China (English)

    Min Min LIANG; Mei Ling QI; Ruo Nong FU

    2005-01-01

    We have investigated the use of flash evaporation, headspace solid-phase microextraction (HS-SPME) and steam distillation (SD) as sample concentration and preparation techniques for the analysis of volatile constituents present in Houttuynia cordata Thunb. The samples were analyzed by gas chromatography (GC) and identified by mass spectrometry (MS).Comparison studies were performed. It was found that the results obtained between Headspace solid-phase microextraction HS-SPME and SD techniques were in good agreement. Seventy-nine compounds in Houttuynia cordata Thunb were identified by MS. In flash evaporation, thirty-nine compounds were identified. Discrimination in the response for many constituents studied was not observed, which can be clearly observed in SD and HS-SPME techniques. As a conclusion,HS-SPME is a powerful tool for determining the volatile constitutes present in the Houttuynia cordata.

  20. Evaluation of dynamic headspace with gas chromatography/mass spectrometry for the determination of 1,1,1-trichloroethane, trichloroethanol, and trichloroacetic acid in biological samples.

    Science.gov (United States)

    Johns, Douglas O; Dills, Russell L; Morgan, Michael S

    2005-03-25

    A sensitive and reproducible method is described for the analysis of trichloroacetic acid in urine and 1,1,1-trichloroethane in blood using dynamic headspace GC/MS. Samples were analyzed using the soil module of a modified purge and trap autosampler to facilitate the use of disposable purging vessels. Coefficients of variation were below 3.5% for both analytes, and response was linear in the range of 0.01-7.0 microg/ml for trichloroacetic acid and 0.9 ng/ml-2.2 microg/ml for 1,1,1-trichloroethane. Attempts at using dynamic headspace for the analysis of trichloroethanol in urine were unsuccessful.

  1. Assessment of the degradation of polyurethane foams after artificial and natural ageing by using pyrolysis-gas chromatography/mass spectrometry and headspace-solid phase microextraction-gas chromatography/mass spectrometry.

    Science.gov (United States)

    Lattuati-Derieux, A; Thao-Heu, S; Lavédrine, B

    2011-07-15

    Polyurethane foams are widely present in museum collections either as part of the artefacts, or as a material for their conservation. Unfortunately many of PU foam artefacts are in poor condition and often exhibit specific conservation issues. Their fast thermal and photochemical degradations have been the aim of previous researches. It is now accepted that hydrolysis predominates for polyester-based polyurethane PU(ES) whereas oxidation is the principal cause of degradation for polyether-based polyurethane PU(ET) variety. Only a few studies have been devoted to volatile organic compounds (VOCs) emitted by polyurethanes and, to our knowledge, none were performed on polyurethane foams by using headspace-solid phase microextraction (HS-SPME). The objective of the work described here is to assess the impact of some environmental factors (humidity, temperature and daylight) on the degradation of PU foams by evaluating their volatile fractions. We investigated morphological changes, polymerized fractions and volatile fractions of (i) one modern produced PU(ES) foam and one modern PU(ET) foam artificially aged in different conditions as well as (ii) four naturally aged foams collected from various daily life objects and selected for the representativeness of their analytical data. Characterization procedure used was based on attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and non-invasive headspace solid-phase microextraction coupled with gas chromatography and mass spectrometry (HS-SPME-GC/MS). In this paper, the formation of alcohol and acid raw products for PU(ES) and glycol derivatives for PU(ET) during natural and artificial ageing is confirmed. These main products can be considered as degradation markers for PU foams. Results show that artificial and natural ageing provide similar analytical results, and confirm that the dominant degradation paths for PU(ES) and for PU(ET) are

  2. Time since discharge of 9mm cartridges by headspace analysis, part 2: Ageing study and estimation of the time since discharge using multivariate regression.

    Science.gov (United States)

    Gallidabino, M; Romolo, F S; Weyermann, C

    2017-03-01

    Estimating the time since discharge of spent cartridges can be a valuable tool in the forensic investigation of firearm-related crimes. To reach this aim, it was previously proposed that the decrease of volatile organic compounds released during discharge is monitored over time using non-destructive headspace extraction techniques. While promising results were obtained for large-calibre cartridges (e.g., shotgun shells), handgun calibres yielded unsatisfying results. In addition to the natural complexity of the specimen itself, these can also be attributed to some selective choices in the methods development. Thus, the present series of papers aimed to systematically evaluate the potential of headspace analysis to estimate the time since discharge of cartridges through the use of more comprehensive analytical and interpretative techniques. Following the comprehensive optimisation and validation of an exhaustive headspace sorptive extraction (HSSE) method in the first part of this work, the present paper addresses the application of chemometric tools in order to systematically evaluate the potential of applying headspace analysis to estimate the time since discharge of 9mm Geco cartridges. Several multivariate regression and pre-treatment methods were tested and compared to univariate models based on non-linear regression. Random forests (RF) and partial least squares (PLS) proceeded by pairwise log-ratios normalisation (PLR) showed the best results, and allowed to estimate time since discharge up to 48h of ageing and to differentiate recently fired from older cartridges (e.g., less than 5h compared to more than 1-2 days). The proposed multivariate approaches showed significant improvement compared to univariate models. The effects of storage conditions were also tested and results demonstrated that temperature, humidity and cartridge position should be taken into account when estimating the time since discharge.

  3. Quantification of acetaldehyde and carbon dioxide in the headspace of malignant and non-malignant lung cells in vitro by SIFT-MS.

    Science.gov (United States)

    Sulé-Suso, Josep; Pysanenko, Andriy; Spanel, Patrik; Smith, David

    2009-12-01

    Previous studies using selected ion flow tube mass spectrometry, SIFT-MS, showed that CALU-1 lung cancer cell cultures emit acetaldehyde in proportion to the number of cells in the culture medium. However, studies in another laboratory led to conflicting results, so these SIFT-MS studies have been repeated and extended to include NL20 normal lung epithelial cells and 35FL121 Tel+ telomerase positive lung fibroblast cells. Thus, SIFT-MS has been used to quantify acetaldehyde and, additionally, carbon dioxide, acetone and ethanol in the headspace of the cell culture medium alone and the headspace of the appropriate medium containing 50 x 10(6) or 80 x 10(6) cells following incubation for 16 h at 37 degrees C. Three independent experiments were carried out for each cell type for both cell numbers and for each of the two culture media used. The results showed that acetone and ethanol were only released by the culture medium, specifically from the foetal calf serum contained in the medium, and not by the cells. Acetaldehyde was also released by the medium, but at relatively lower levels than the other three compounds, and was also generated by the CALU-1 and NL20 cell cultures in proportions to the number of cells in the medium. However, following incubation, the acetaldehyde levels in the headspace of the 35FL121 Tel+ cell cultures were much lower than those present in the headspace of the medium alone. Carbon dioxide was clearly generated by the CALU-1 and 35FL121 Tel+ cells indicating that they were respiring normally, but much less was produced by the NL20 cells, presumably indicating that normal metabolism was being inhibited.

  4. A comparative study of three tissue-cultured Dendrobium species and their wild correspondences by headspace gas chromatography–mass spectrometry combined with chemometric methods

    OpenAIRE

    Nai-Dong Chen; Tao You; Jun Li; Li-Tao Bai; Jing-Wen Hao; Xiao-Yuan Xu

    2016-01-01

    Plant tissue culture technique is widely used in the conservation and utilization of rare and endangered medicinal plants and it is crucial for tissue culture stocks to obtain the ability to produce similar bioactive components as their wild correspondences. In this paper, a headspace gas chromatography–mass spectrometry method combined with chemometric methods was applied to analyze and evaluate the volatile compounds in tissue-cultured and wild Dendrobium huoshanense Cheng and Tang, Dendrob...

  5. Orthogonal Design Study on Factors Affecting the Determination of Common Odors in Water Samples by Headspace Solid-Phase Microextraction Coupled to GC/MS

    OpenAIRE

    Shifu Peng; Zhen Ding; Weiwen Xia; Hao Zheng; Yuting Xia; Xiaodong Chen

    2013-01-01

    Geosmin and 2-MIB are responsible for the majority of earthy and musty events related to the drinking water. These two odorants have extremely low odor threshold concentrations at ng L−1 level in the water, so a simple and sensitive method for the analysis of such trace levels was developed by headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry. In this study, the orthogonal experiment design L32 (49) was applied to arrange and optimize experimental condition...

  6. Components detected by headspace-solid phase microextraction in artisanal fresh goat's cheese smoked using dry prickly pear (Opuntia ficus indica)

    OpenAIRE

    Guillén, María; Ibargoitia, María; Sopelana, Patricia; Palencia, Gemma

    2004-01-01

    International audience; The study of the headspace components of six different samples of hand-made fresh goat's cheese smoked with dry prickly pear (Opuntia ficus indica) smoke, protected by the Palmero Denomination of Origin, was carried out. These cheeses were manufactured by six different artisans from the Island of Palma. In spite of this cheese not being a ripened cheese, more than 330 components were detected, by means of solid phase microextraction using a polyacrylate fiber followed ...

  7. Determination of residual acetone and acetone related impurities in drug product intermediates prepared as Spray Dried Dispersions (SDD) using gas chromatography with headspace autosampling (GCHS).

    Science.gov (United States)

    Quirk, Emma; Doggett, Adrian; Bretnall, Alison

    2014-08-05

    Spray Dried Dispersions (SDD) are uniform mixtures of a specific ratio of amorphous active pharmaceutical ingredient (API) and polymer prepared via a spray drying process. Volatile solvents are employed during spray drying to facilitate the formation of the SDD material. Following manufacture, analytical methodology is required to determine residual levels of the spray drying solvent and its associated impurities. Due to the high level of polymer in the SDD samples, direct liquid injection with Gas Chromatography (GC) is not a viable option for analysis. This work describes the development and validation of an analytical approach to determine residual levels of acetone and acetone related impurities, mesityl oxide (MO) and diacetone alcohol (DAA), in drug product intermediates prepared as SDDs using GC with headspace (HS) autosampling. The method development for these analytes presented a number of analytical challenges which had to be overcome before the levels of the volatiles of interest could be accurately quantified. GCHS could be used after two critical factors were implemented; (1) calculation and application of conversion factors to 'correct' for the reactions occurring between acetone, MO and DAA during generation of the headspace volume for analysis, and the addition of an equivalent amount of polymer into all reference solutions used for quantitation to ensure comparability between the headspace volumes generated for both samples and external standards. This work describes the method development and optimisation of the standard preparation, the headspace autosampler operating parameters and the chromatographic conditions, together with a summary of the validation of the methodology. The approach has been demonstrated to be robust and suitable to accurately determine levels of acetone, MO and DAA in SDD materials over the linear concentration range 0.008-0.4μL/mL, with minimum quantitation limits of 20ppm for acetone and MO, and 80ppm for DAA.

  8. Use of volatile organic solvents in headspace liquid-phase microextraction by direct cooling of the organic drop using a simple cooling capsule.

    Science.gov (United States)

    Ghiasvand, Ali Reza; Yazdankhah, Fatemeh; Hajipour, Somayeh

    2016-08-01

    A low-cost and simple cooling-assisted headspace liquid-phase microextraction device for the extraction and determination of 2,6,6-trimethyl-1,3 cyclohexadiene-1-carboxaldehyde (safranal) in Saffron samples, using volatile organic solvents, was fabricated and evaluated. The main part of the cooling-assisted headspace liquid-phase microextraction system was a cooling capsule, with a Teflon microcup to hold the extracting organic solvent, which is able to directly cool down the extraction phase while the sample matrix is simultaneously heated. Different experimental factors such as type of organic extraction solvent, sample temperature, extraction solvent temperature, and extraction time were optimized. The optimal conditions were obtained as: extraction solvent, methanol (10 μL); extraction temperature, 60°C; extraction solvent temperature, 0°C; and extraction time, 20 min. Good linearity of the calibration curve (R(2) = 0.995) was obtained in the concentration range of 0.01-50.0 μg/mL. The limit of detection was 0.001 μg/mL. The relative standard deviation for 1.0 μg/mL of safranal was 10.7% (n = 6). The proposed cooling-assisted headspace liquid-phase microextraction device was coupled (off-line) to high-performance liquid chromatography and used for the determination of safranal in Saffron samples. Reasonable agreement was observed between the results of the cooling-assisted headspace liquid-phase microextraction high-performance liquid chromatography method and those obtained by a validated ultrasound-assisted solvent extraction procedure.

  9. Development of a dynamic headspace solid-phase microextraction procedure coupled to GC–qMSD for evaluation the chemical profile in alcoholic beverages

    OpenAIRE

    Rodrigues, F.; Caldeira, M; Câmara, José de Sousa

    2008-01-01

    In the present study, a simple and sensitive methodology based on dynamic headspace solid-phase microextraction (HS-SPME) followed by thermal desorption gas chromatography with quadrupole mass detection (GC–qMSD), was developed and optimized for the determination of volatile (VOCs) and semi-volatile (SVOCs) compounds from different alcoholic beverages: wine, beer and whisky. Key experimental factors influencing the equilibrium of the VOCs and SVOCs between the sample and the SPME fibre, as th...

  10. Simultaneous identification and qualitative determination of hydrocyanic acid and phosphine by gas chromatography with nitrogen-phosphorus detector and Headspace autosampler (hs-gc-npd) in biological fluids

    OpenAIRE

    Monsalve-Salamanca, Luz Adriana; Ortiz-Rangel, María Martha; Mateus-Fontecha, Alexis

    2015-01-01

    Introduction: This article described a simple, rapid, sensitive methodology for the identification and qualitative determination of phosphine and hydrocyanic cyanide in biological (i.e., blood and stomach contents) and non-biological samples by gas chromatography (gc). Methodology: The foregoing was carried out by a selective nitrogen-phosphorus detector (npd) and Headspace (hs) volatile autosampler using acetonitrile (acn) as internal standard (istd). The procedure involves taking and pourin...

  11. Detecting volatile compounds from Kraft lignin degradation in the headspace of microbial cultures by selected ion flow tube mass spectrometry (SIFT-MS).

    Science.gov (United States)

    Gibson, Andrew; Malek, Lada; Dekker, Robert F H; Ross, Brian

    2015-05-01

    Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) was used to quantify methanol and other volatile compounds in the headspace of one bacterial and 12 fungal lignin-degrading microbial cultures. Cultures were grown in 250 mL Erlenmeyer flasks capped with aluminum foil containing 40 mL of nutrient media using Kraft lignin (0.3% w/v) as the sole carbon source. Analysis was done using SIFT-MS with H3O(+) and NO(+) precursors. Product ions were identified with multiple ion mode (MIM). Full scan (FS) mode was used to identify other compounds of interest. Absidia cylindrospora, Ischnoderma resinosum and Pholiota aurivella increased headspace methanol concentration by 136 ppb, 1196 ppb and 278 ppb, respectively, while Flammulina velutipes and Laetiporus sulphureus decreased concentration below ambient levels. F. velutipes and L. sulphureus were found to produce products of methanol oxidation (formaldehyde and formic acid) and were likely metabolizing methanol. Some additional unidentified compounds generated by the fungal cultures are intriguing and will require further study. SIFT-MS can be used to quantify methanol and other volatile compounds in the headspace of microbial cultures and has the potential to be a rapid, sensitive, non-invasive tool useful in elucidating the mechanisms of lignin degradative pathways.

  12. Purge-assisted headspace solid-phase microextraction combined with gas chromatography-mass spectrometry for determination of chlorophenols in aqueous samples.

    Science.gov (United States)

    Ho, Hsin-Pin; Lee, Ren-Jye; Lee, Maw-Rong

    2008-12-12

    A simple, economical and very effective method is demonstrated for simultaneous determination of 2,4-dichlorophenol, 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol, in aqueous samples, by using purge-assisted headspace solid-phase microextraction (PA/HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). In the new method, purging the sample enhances the removal of the trace chlorophenols without derivatization from the matrices to the headspace. Extraction parameters including extraction temperature, purge gas flow rate and extraction time were systematically investigated. Under optimal conditions, the relative standard deviations (RSDs) were 4-11% at 50 pg/mL and 5-14% at 5 pg/mL, respectively. The recoveries were in the range of 83-114%. Detection limits were determined at the fg level. These results indicate that PA/HS-SPME provides a significant contribution to highly efficient extraction of semi-volatile CPs, especially for pentachlorophenol, which has the smallest Henry's constant and large octanol-water partitioning coefficient. In addition, the proposed method was successfully applied to the analysis of chlorophenols in landfill leachate. New perspectives are opened for headspace extraction of relatively low vapor pressure compounds in complex matrices.

  13. Headspace-multicapillary column-ion mobility spectrometry for the direct analysis of 2,4,6-trichloroanisole in wine and cork samples.

    Science.gov (United States)

    Márquez-Sillero, Isabel; Cárdenas, Soledad; Valcárcel, Miguel

    2012-11-23

    Headspace-multicapillary column-ion mobility spectrometry coupling has been evaluated for the direct analysis of wine and cork stopper samples for the determination of 2,4,6-trichloroanisole (2,4,6-TCA). The instrumental configuration permits the sample to be introduced in headspace vials which are placed into the autosampler oven in order to facilitate the transference of the volatile compounds from the sample to its headspace. Further, an aliquot of 200 μL of the homogenized gaseous phase is injected into the multicapillary column in order to separate the target compounds from potential interferents. The detection of 2,4,6-TCA was carried out in an ion mobility spectrometer with a radioactive source and working under negative mode. All the system was computer controlled, including data acquisition and treatment. The limits of detection achieved were 0.012 ng L(-1) for wine and 0.28 ng g(-1) for the cork stopper. The procedure was applied to the analysis of commercial wine samples in different packages and 2,4,6-TCA was found in all of those closed with a cork stopper. The excellent recovery values obtained testify for the goodness of the method as no interference from the sample matrix exits.

  14. Ultrasonic nebulization extraction-heating gas flow transfer-headspace single drop microextraction of essential oil from pericarp of Zanthoxylum bungeanum Maxim.

    Science.gov (United States)

    Wei, Shigang; Zhang, Huihui; Wang, Yeqiang; Wang, Lu; Li, Xueyuan; Wang, Yinghua; Zhang, Hanqi; Xu, Xu; Shi, Yuhua

    2011-07-22

    The ultrasonic nebulization extraction-heating gas flow transfer coupled with headspace single drop microextraction (UNE-HGFT-HS-SDME) was developed for the extraction of essential oil from Zanthoxylum bungeanum Maxim. The gas chromatography-mass spectrometry was applied to the determination of the constituents in the essential oil. The contents of the constituents from essential oil obtained by the proposed method were found to be more similar to those obtained by hydro-distillation (HD) than those obtained by ultrasonic nebulization extraction coupled with headspace single drop microextraction (UNE-HS-SDME). The heating gas flow was firstly used in the analysis of the essential oil to transfer the analytes from the headspace to the solvent microdrop. The relative standard deviations for determining the five major constituents were in the range from 1.5 to 6.7%. The proposed method is a fast, sensitive, low cost and small sample consumption method for the determination of the volatile and semivolatile constituents in the plant materials.

  15. Extraction of formic and acetic acids from aqueous solution by dynamic headspace-needle trap extraction temperature and pH optimization.

    Science.gov (United States)

    Lou, Da-Wei; Lee, Xinqing; Pawliszyn, Janusz

    2008-08-08

    A combined method of dynamic headspace-needle trap sample preparation and gas chromatography for the determination of formic and acetic acids in aqueous solution was developed in this study. A needle extraction device coupled with a gas aspirating pump was intended to perform sampling and preconcentration of target compounds from aqueous sample before gas chromatographic analysis. The needle trap extraction (NTE) technique allows for the successful sampling of short chain fatty acids under dynamic conditions while keeping the headspace (HS) volume constant. Two important parameters, including extraction temperature and effect of acidification, have been optimized and evaluated using the needle trap device. The method detection limits for the compounds estimated were 87.2microg/L for acetic acid and 234.8microg/L for formic acid in spite of the low flame ionization detection response for formic acid and its low Henry's law constant in aqueous solution. Precision was determined based on the two real samples and ranged between 4.7 and 10.7%. The validated headspace-needle trap extraction method was also successfully applied to several environmental samples.

  16. Identification and Quantitation of Volatile Organic Compounds in Poly(methyl methacrylate) Kitchen Utensils by Headspace Gas Chromatography/Mass Spectrometry.

    Science.gov (United States)

    Ohno, Hiroyuki; Mutsuga, Motoh; Kawamura, Yoko

    2014-01-01

    A headspace GC/MS method was developed for identification and quantitation of residual volatile organic compounds in poly(methyl methacrylate) (PMMA) kitchen utensils. A sample was cut into small pieces, then N,N-dimethylacetamide was added in a headspace vial and sealed. After storing for more than 1 day at room temperature, the vial was incubated for 1 h at 90°C, and the headspace gas was analyzed by GC/MS. In 24 PMMA kitchen utensils, 16 volatile organic compounds including methyl methacrylate, methyl acrylate, toluene, 2-methyl-1-butene, 2-methyl-2-butene, 2-methylpropanal, methyl propionate, methyl isobutyrate, trans-3-heptene, heptane, cis-3-heptene, trans-2-heptene, cis-2-heptene, 2,4,4-trimethyl-1-pentene, 2,4,4-trimethyl-2-pentene, and 1-octene were identified and quantitated. These 15 volatile compounds except methyl methacrylate were found for the first time in PMMA kitchen utensils. Recovery rates from spiked samples were 97.4-104.0% with CV values of 2.8-9.6%. Samples contained 190-7900 μg/g of methyl methacrylate, 26-810 μg/g of methyl acrylate, and 2-1300 μg/g of toluene; other compounds were at levels less than 100 μg/g. Methyl methacrylate was the main monomer of PMMA and methyl acrylate was a comonomer; toluene should be used as a solvent.

  17. Multivariate analysis of the volatile components in tobacco based on infrared-assisted extraction coupled to headspace solid-phase microextraction and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Yang, Yanqin; Pan, Yuanjiang; Zhou, Guojun; Chu, Guohai; Jiang, Jian; Yuan, Kailong; Xia, Qian; Cheng, Changhe

    2016-11-01

    A novel infrared-assisted extraction coupled to headspace solid-phase microextraction followed by gas chromatography with mass spectrometry method has been developed for the rapid determination of the volatile components in tobacco. The optimal extraction conditions for maximizing the extraction efficiency were as follows: 65 μm polydimethylsiloxane-divinylbenzene fiber, extraction time of 20 min, infrared power of 175 W, and distance between the infrared lamp and the headspace vial of 2 cm. Under the optimum conditions, 50 components were found to exist in all ten tobacco samples from different geographical origins. Compared with conventional water-bath heating and nonheating extraction methods, the extraction efficiency of infrared-assisted extraction was greatly improved. Furthermore, multivariate analysis including principal component analysis, hierarchical cluster analysis, and similarity analysis were performed to evaluate the chemical information of these samples and divided them into three classifications, including rich, moderate, and fresh flavors. The above-mentioned classification results were consistent with the sensory evaluation, which was pivotal and meaningful for tobacco discrimination. As a simple, fast, cost-effective, and highly efficient method, the infrared-assisted extraction coupled to headspace solid-phase microextraction technique is powerful and promising for distinguishing the geographical origins of the tobacco samples coupled to suitable chemometrics.

  18. Analysis of Odorants in Marking Fluid of Siberian Tiger (Panthera tigris altaica Using Simultaneous Sensory and Chemical Analysis with Headspace Solid-Phase Microextraction and Multidimensional Gas Chromatography-Mass Spectrometry-Olfactometry

    Directory of Open Access Journals (Sweden)

    Simone B. Soso

    2016-06-01

    Full Text Available Scent-marking is the most effective method of communication in the presence or absence of a signaler. These complex mixtures result in a multifaceted interaction triggered by the sense of smell. The objective was to identify volatile organic compound (VOC composition and odors emitted by total marking fluid (MF associated with Siberian tigers (Panthera tigris altaica. Siberian tiger, an endangered species, was chosen because its MF had never been analyzed. Solid phase microextraction (SPME for headspace volatile collection combined with multidimensional gas chromatography-mass spectrometry-olfactometry for simultaneous chemical and sensory analyses were used. Thirty-two VOCs emitted from MF were identified. 2-acetyl-1-pyrroline, the sole previously identified compound responsible for the “characteristic” odor of P. tigris MF, was identified along with two additional compounds confirmed with standards (urea, furfural and four tentatively identified compounds (3-methylbutanamine, (R-3-methylcyclopentanone, propanedioic acid, and 3-hydroxybutanal as being responsible for the characteristic aroma of Siberian tiger MF. Simultaneous chemical and sensory analyses improved characterization of scent-markings and identified compounds not previously reported in MF of other tiger species. This research will assist animal ecologists, behaviorists, and zookeepers in understanding how scents from specific MF compounds impact tiger and wildlife communication and improve management practices related to animal behavior. Simultaneous chemical and sensory analyses is applicable to unlocking scent-marking information for other species.

  19. Report of the Peer Review Panel on the early site suitability evaluation of the Potential Repository Site at Yucca Mountain, Nevada; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-01-01

    The US Department of Energy (DOE) Yucca mountain Site Characterization Project Office (YMPO) assigned Science Applications International Corporation (SAIC), the Technical and Management Support Services (T&MSS) contractor to the YmPo, the task of conducting an Early Site Suitability Evaluation (ESSE) of the Yucca mountain site as a potential site for a high-level radioactive waste repository. First, the assignment called for the development of a method to evaluate a single site against the DOE General Guidelines for Recommendation of Sites for Nuclear Waste Repositories, 10 CFR Part 960. Then, using this method, an evaluation team, the ESSE Core Team, of senior YMP scientists, engineers, and technical experts, evaluated new information obtained about the site since publication of the final Environmental Assessment (DOE, 1986) to determine if new suitability/unsuitability findings could be recommended. Finally, the Core Team identified further information and analyses needed to make final determinations for each of the guidelines. As part of the task, an independent peer review of the ESSE report has been conducted. Expertise was solicited that covered the entire spectrum of siting guidelines in 10 CFR Part 960 in order to provide a complete, in-depth critical review of the data evaluated and cited in the ESSE report, the methods used to evaluate the data, and the conclusions and recommendations offered by the report. Fourteen nationally recognized technical experts (Table 2) served on the Peer Review Panel. The comments from the Panel and the responses prepared by the ESSE Core Team, documented on formal Comment Response Forms, constitute the body of this document.

  20. Comparison of Two Surface Contamination Sampling Techniques Conducted for the Characterization of Two Pajarito Site Manhattan Project National Historic Park Properties

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, Tammy Ann [Montana Tech of the Univ. of Montana, Butte, MT (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-07-29

    Technical Area-18 (TA-18), also known as Pajarito Site, is located on Los Alamos National Laboratory property and has historic buildings that will be included in the Manhattan Project National Historic Park. Characterization studies of metal contamination were needed in two of the four buildings that are on the historic registry in this area, a “battleship” bunker building (TA-18-0002) and the Pond cabin (TA-18-0029). However, these two buildings have been exposed to the elements, are decades old, and have porous and rough surfaces (wood and concrete). Due to these conditions, it was questioned whether standard wipe sampling would be adequate to detect surface dust metal contamination in these buildings. Thus, micro-vacuum and surface wet wipe sampling techniques were performed side-by-side at both buildings and results were compared statistically. A two-tail paired t-test revealed that the micro-vacuum and wet wipe techniques were statistically different for both buildings. Further mathematical analysis revealed that the wet wipe technique picked up more metals from the surface than the microvacuum technique. Wet wipes revealed concentrations of beryllium and lead above internal housekeeping limits; however, using an yttrium normalization method with linear regression analysis between beryllium and yttrium revealed a correlation indicating that the beryllium levels were likely due to background and not operational contamination. PPE and administrative controls were implemented for National Park Service (NPS) and Department of Energy (DOE) tours as a result of this study. Overall, this study indicates that the micro-vacuum technique may not be an efficient technique to sample for metal dust contamination.

  1. Full evaporation dynamic headspace and gas chromatography-mass spectrometry for uniform enrichment of odor compounds in aqueous samples.

    Science.gov (United States)

    Ochiai, Nobuo; Sasamoto, Kikuo; Hoffmann, Andreas; Okanoya, Kazunori

    2012-06-01

    A method for analysis of a wide range of odor compounds in aqueous samples at sub-ng mL⁻¹ to μg mL⁻¹ levels was developed by full evaporation dynamic headspace (FEDHS) and gas chromatography-mass spectrometry (GC-MS). Compared to conventional DHS and headspace solid phase microextraction (HS-SPME), FEDHS provides more uniform enrichment over the entire polarity range for odor compounds in aqueous samples. FEDHS at 80°C using 3 L of purge gas allows complete vaporization of 100 μL of an aqueous sample, and trapping and drying it in an adsorbent packed tube, while providing high recoveries (85-103%) of the 18 model odor compounds (water solubility at 25°C: log0.54-5.65 mg L⁻¹, vapor pressure at 25°C: 0.011-3.2 mm Hg) and leaving most of the low volatile matrix behind. The FEDHS-GC-MS method showed good linearity (r²>0.9909) and high sensitivity (limit of detection: 0.21-5.2 ng mL⁻¹) for the model compounds even with the scan mode in the conventional MS. The feasibility and benefit of the method was demonstrated with analyses of key odor compounds including hydrophilic and less volatile characteristics in beverages (whiskey and green tea). In a single malt whiskey sample, phenolic compounds including vanillin could be determined in the range of 0.92-5.1 μg mL⁻¹ (RSD<7.4%, n=6). For a Japanese green tea sample, 48 compounds including 19 potent odorants were positively identified from only 100 μL of sample. Heat-induced artifact formation for potent odorants was also examined and the proposed method does not affect the additional formation of thermally generated compounds. Eighteen compounds including 12 potent odorants (e.g. coumarin, furaneol, indole, maltol, and pyrazine congeners) were determined in the range of 0.21-110 ng mL⁻¹ (RSD<10%, n=6).

  2. RESULTS FROM THE (1) DATA COLLECTION WORKSHOP, (2) MODELING WORKSHOP AND (3) DRILLING AND CORING METHODS WORKSHOP AS PART OF THE JOINT INDUSTRY PARTICIPATION (JIP) PROJECT TO CHARACTERIZE NATURAL GAS HYDRATES IN THE DEEPWATER GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Stephen A. Holditch; Emrys Jones

    2002-09-01

    In 2000, Chevron began a project to learn how to characterize the natural gas hydrate deposits in the deepwater portions of the Gulf of Mexico. A Joint Industry Participation (JIP) group was formed in 2001, and a project partially funded by the U.S. Department of Energy (DOE) began in October 2001. The primary objective of this project is to develop technology and data to assist in the characterization of naturally occurring gas hydrates in the deepwater Gulf of Mexico. These naturally occurring gas hydrates can cause problems relating to drilling and production of oil and gas, as well as building and operating pipelines. Other objectives of this project are to better understand how natural gas hydrates can affect seafloor stability, to gather data that can be used to study climate change, and to determine how the results of this project can be used to assess if and how gas hydrates act as a trapping mechanism for shallow oil or gas reservoirs. As part of the project, three workshops were held. The first was a data collection workshop, held in Houston during March 14-15, 2002. The purpose of this workshop was to find out what data exist on gas hydrates and to begin making that data available to the JIP. The second and third workshop, on Geoscience and Reservoir Modeling, and Drilling and Coring Methods, respectively, were held simultaneously in Houston during May 9-10, 2002. The Modeling Workshop was conducted to find out what data the various engineers, scientists and geoscientists want the JIP to collect in both the field and the laboratory. The Drilling and Coring workshop was to begin making plans on how we can collect the data required by the project's principal investigators.

  3. Final technical report for project titled Quantitative Characterization of Cell Aggregation/Adhesion as Predictor for Distribution and Transport of Microorganisms in Subsurface Environment

    Energy Technology Data Exchange (ETDEWEB)

    Gu, April Z. [Northeastern Univ., Boston, MA (United States); Wan, Kai-tak [Northeastern Univ., Boston, MA (United States)

    2014-09-02

    This project aims to explore and develop enabling methodology and techniques for nano-scale characterization of microbe cell surface contact mechanics, interactions and adhesion quantities that allow for identification and quantification of indicative properties related to microorganism migration and transport behavior in porous media and in subsurface environments. Microbe transport has wide impact and therefore is of great interest in various environmental applications such as in situ or enhanced subsurface bioremediation,filtration processes for water and wastewater treatments and protection of drinking water supplies. Although great progress has been made towards understanding the identities and activities of these microorganisms in the subsurface, to date, little is known of the mechanisms that govern the mobility and transport of microorganisms in DOE’s contaminated sites, making the outcomes of in situ natural attenuation or contaminant stability enhancement unpredictable. Conventionally, movement of microorganisms was believed to follows the rules governing solute (particle) transport. However, recent studies revealed that cell surface properties, especially those pertaining to cell attachment/adhesion and aggregation behavior, can cause the microbe behavior to deviate from non-viable particles and hence greatly influence the mobility and distribution of microorganisms in porous media.This complexity highlights the need to obtain detailed information of cell-cell and cell-surface interactions in order to improve and refine the conceptual and quantitative model development for fate and transport of microorganisms and contaminant in subsurface. Traditional cell surface characterization methods are not sufficient to fully predict the deposition rates and transport behaviors of microorganism observed. A breakthrough of methodology that would allow for quantitative and molecular-level description of intrinsic cell surface properties indicative for cell

  4. Project Prometheus

    Science.gov (United States)

    Johnson, Steve

    2003-01-01

    Project Prometheus will enable a new paradigm in the scientific exploration of the Solar System. The proposed JIMO mission will start a new generation of missions characterized by more maneuverability, flexibility, power and lifetime. Project Prometheus organization is established at NASA Headquarters: 1.Organization established to carry out development of JIMO, nuclear power (radioisotope), and nuclear propulsion research. 2.Completed broad technology and national capacity assessments to inform decision making on planning and technology development. 3.Awarded five NRA s for nuclear propulsion research. 4.Radioisotope power systems in development, and Plutonium-238 being purchased from Russia. 5.Formulated science driven near-term and long-term plan for the safe utilization of nuclear propulsion based missions. 6.Completed preliminary studies (Pre-Phase A) of JIMO and other missions. 7.Initiated JIMO Phase A studies by Contractors and NASA.

  5. Headspace gas chromatography with flame ionization detection (HS-GC-FID) for the determination of dissolved methane in wastewater.

    Science.gov (United States)

    Beale, D J; Tjandraatmadja, G; Toifl, M; Goodman, N

    2014-01-01

    There is currently a need for a simple, accurate and reproducible method that quantifies the amount of dissolved methane in wastewater in order to realize the potential methane that can be recovered and account for any emissions. This paper presents such a method, using gas chromatography with flame ionization detection fitted with a GS-Gas PRO column coupled with a headspace auto sampler. A practical limit of detection for methane of 0.9 mg L(-1), with a retention time of 1.24 min, was obtained. It was found that the reproducibility and accuracy of the method increased significantly when samples were collected using an in-house constructed bailer sampling device and with the addition of 100 μL hydrochloric acid (HCl) and 25% sodium chloride (NaCl) and sonication for 30 min prior to analysis. Analysis of wastewater samples and wastewater sludge collected from a treatment facility were observed to range from 12.51 to 15.79 mg L(-1) (relative standard deviation (RSD) 8.1%) and 17.56 to 18.67 mg L(-1) (RSD 3.4%) respectively. The performance of this method was validated by repeatedly measuring a mid-level standard (n=8; 10 mg L(-1)), with an observed RSD of 4.6%.

  6. Fast quality assessment of German chamomile (Matricaria chamomilla L.) by headspace solid-phase microextraction: influence of flower development stage.

    Science.gov (United States)

    Rafieiolhossaini, Mohammad; Adams, An; Sodaeizadeh, Hamid; Van Damme, Patrick; De Kimpe, Norbert

    2012-01-01

    For an adequate quality evaluation of aromatic plants grown under different conditions, a rapid, simple and sensitive method for the analysis of volatile constituents is indispensable. The main objective of the present study was to compare fast screening of German chamomile (Matricaria chamomilla L.) by means of headspace solid-phase microextraction (HS-SPME) with conventional isolation of the essential oil (steam distillation-solvent extraction (SDSE)) for the differentiation of chamomile essential oil constituents. Flowers were harvested at two distinct development stages: stage I, when ligulate flowers start to develop and tubular flowers are still closed, and stage II, when tubular flowers are partially to completely opened. Dried chamomile flowers at two development stages were extracted by means of both SDSE and HS-SPME, followed by GC-MS analysis. Among 30 compounds detected, (E)-beta-farnesene (49%), artemisia ketone (10%) and germacrene D (9%) were the predominant volatile components in the HS-SPME-extract, while alpha-bisabolol oxide A (42%), chamazulene (21%) and (Z)-spiroether (8%) were the main essential oil constituents among the 13 compounds obtained by SDSE. After statistical analysis of the data, both techniques enabled the same conclusion: (E)-beta-farnesene was the only compound which showed significant differences between the two flower development stages. These results suggest that HS-SPME-GC-MS can be used as a sensitive technique for the rapid screening and quality assessment of M. chamomilla.

  7. [Determination of dichloromethane and trichloromethane residues in ranitidine hydrochloride by headspace liquid phase microextraction coupled with gas chromatography].

    Science.gov (United States)

    Shen, Shuchang; Yun, Dan; Li, Fei

    2009-11-01

    A method for the determination of residual dichloromethane and trichloromethane in ranitidine hydrochloride by headspace liquid phase microextraction coupled with gas chromatography (GC) was developed. A homemade device was used to protect the organic drop. The effects of the nature of extraction solvent, extraction time, extraction temperature and microdrop volume on the extraction efficiency were investigated separately. The optimal experimental conditions were as follows: 2 microL of n-tridecane as extraction solvent, 30 min of extraction time, 60 degrees C of extraction temperature. The correlation coefficients of linear calibration curve were 0.9733 and 0.9724 within the concentration ranges of dichloromethane (1-10 microg/g) and trichloromethane (1-10 microg/g), respectively. The detection limits of dichlormethane and trichloromethane were 0.0273 microg/g and 0.0410 microg/g, respectively, the relative standard deviations were lower than 4.36% and 5.89%, and the recoveries of the method were 93.6%-102% and 98.1% respectively. The method is simple and reliable.

  8. Nuclear Magnetic Resonance and Headspace Solid-Phase Microextraction Gas Chromatography as Complementary Methods for the Analysis of Beer Samples

    Directory of Open Access Journals (Sweden)

    Sarah R. Johnson

    2017-04-01

    Full Text Available Chemical analysis of the organic components in beer has applications to quality control, authenticity and improvements to the flavor characteristics and brewing process. This study aims to show the complementary nature of two instrumental techniques which, in combination, can identify and quantify a number of organic components in a beer sample. Nuclear Magnetic Resonance (NMR was used to provide concentrations of 26 different organic compounds including alcohols, organic acids, carbohydrates, and amino acids. Calorie content was also estimated for the samples. NMR data for ethanol concentrations were validated by comparison to a Fourier Transform Infrared Spectrometry (FTIR method. Headspace Solid-Phase Microextraction (SPME Gas Chromatography Mass Spectrometry (GCMS was used to identify a range of volatile compounds such as alcohols, esters and hop-derived aroma compounds. A simple and inexpensive conversion of a Gas Chromatography Flame Ionization Detector (GC FID instrument to allow the use of Solid-Phase Microextraction was found to be useful for the quantification of volatile esters.

  9. [A novel vapor dynamic headspace enrichment equipment for nontarget screening of volatile organic compounds in drinking water].

    Science.gov (United States)

    Ma, Huilian; Zhang, Haijun; Tian, Yuzeng; Wang, Longxing; Chen, Jiping

    2011-09-01

    A novel vapor dynamic headspace enrichment device was set up for nontarget screening of volatile organic compounds (VOCs) in drinking water. The main operating parameters of this device, such as length of distillation tube, volume of collected condensate, and choice of absorbent, were optimized. In this device, vapor was utilized as a purge gas and water was utilized as a absorbent. With the help of the device, one liter of water sample could be concentrated to 5 mL and the sensitivity of traditional purge and trap-gas chromatography-mass spectrometry (P&T-GC-MS) could be improved 1-2 orders of magnitude. Source and disinfected water samples from a water treatment plant were analyzed with this method. Compared with the traditional P&T-GC-MS analysis without pre-enrichment, the numbers of identified VOCs were improved from 0 to 16 for source water and 5 to 35 for disinfected water samples. It is also shown that there are many halide compounds in VOCs in disinfected water which do not exist in source water.

  10. Determination of roasted pistachio (Pistacia vera L.) key odorants by headspace solid-phase microextraction and gas chromatography-olfactometry.

    Science.gov (United States)

    Aceña, Laura; Vera, Luciano; Guasch, Josep; Busto, Olga; Mestres, Montserrat

    2011-03-23

    Key odorants in roasted pistachio nuts have been determined for the first time. Two different pistachio varieties (Fandooghi and Kerman) have been analyzed by means of headspace solid-phase microextraction (HS-SPME) and gas chromatography-olfactometry (GCO). The aroma extract dilution analyses (AEDA) applied have revealed 46 and 41 odor-active regions with a flavor dilution (FD) factor≥64 for the Fandooghi and the Kerman varieties, respectively, and 39 of them were related to precisely identified compounds. These included esters, pyrazines, aldehydes, acids, furans, and phenols. The results show that the Fandooghi variety presents, not only more odor-active regions but also higher FD factors than the Kerman variety that can lead to the conclusion that the first variety has a richer aromatic profile than the second one. The descriptive sensory analysis (DSA) showed that the roasted, chocolate/coffee, and nutty attributes were rated significantly higher in the Fandooghi variety, whereas the green attribute was significantly higher in the Kerman one.

  11. Determination of Tuta absoluta pheromones in water and tomato samples by headspace-gas chromatography-mass spectrometry.

    Science.gov (United States)

    del Carmen Alcudia-León, María; Lucena, Rafael; Cárdenas, Soledad; Valcárcel, Miguel

    2015-01-01

    Tuta absoluta is a tomato pest which is originally from South America. This pest was detected in eastern Spain in 2006 and it rapidly invaded various European countries and spread throughout the Mediterranean basin. The usual detection of this pest is based on the physical evaluation of the crops and in the exhaustive count of potential insects in dedicated traps. The early detection of that pest on the basis of more objective or measurable indicators is desirable. In this case, the combination of headspace and gas chromatography with mass spectrometric detection is proposed for the identification of Tuta absoluta pest using two of its pheromone components as markers. These components, namely: (3E,8Z,11Z)-tetradecatrien-1-yl acetate and (3E,8Z)-tetradecadien-1-yl acetate, are characteristic of Tuta absoluta and they are not present in other insect pheromones. The developed combination allows the determination of both components in water and tomato samples with limits of detection in the range from 25-32 ng/L to 89-111 ng/kg, respectively. The precision, expressed as relative standard deviation, was better than 4.6% for water samples and better than 7.1% when tomato samples were analyzed. The relative recovery values varied in the interval 94-100 and 83-99% for water and tomato samples.

  12. Multiple responses optimization in the development of a headspace gas chromatography method for the determination of residual solvents in pharmaceuticals

    Directory of Open Access Journals (Sweden)

    Carla M. Teglia

    2015-10-01

    Full Text Available An efficient generic static headspace gas chromatography (HSGC method was developed, optimized and validated for the routine determination of several residual solvents (RS in drug substance, using a strategy with two sets of calibration. Dimethylsulfoxide (DMSO was selected as the sample diluent and internal standards were used to minimize signal variations due to the preparative step. A gas chromatograph from Agilent Model 6890 equipped with flame ionization detector (FID and a DB-624 (30 m×0.53 mm i.d., 3.00 µm film thickness column was used. The inlet split ratio was 5:1. The influencing factors in the chromatographic separation of the analytes were determined through a fractional factorial experimental design. Significant variables: the initial temperature (IT, the final temperature (FT of the oven and the carrier gas flow rate (F were optimized using a central composite design. Response transformation and desirability function were applied to find out the optimal combination of the chromatographic variables to achieve an adequate resolution of the analytes and short analysis time. These conditions were 30 °C for IT, 158 °C for FT and 1.90 mL/min for F. The method was proven to be accurate, linear in a wide range and very sensitive for the analyzed solvents through a comprehensive validation according to the ICH guidelines.

  13. Multiple responses optimization in the development of a headspace gas chromatography method for the determination of residual solvents in pharmaceuticals

    Institute of Scientific and Technical Information of China (English)

    Carla M. Teglia; Milagros Montemurro; María M. De Zan; María S. Cámara

    2015-01-01

    An efficient generic static headspace gas chromatography (HSGC) method was developed, optimized and validated for the routine determination of several residual solvents (RS) in drug substance, using a strategy with two sets of calibration. Dimethylsulfoxide (DMSO) was selected as the sample diluent and internal standards were used to minimize signal variations due to the preparative step. A gas chroma-tograph from Agilent Model 6890 equipped with flame ionization detector (FID) and a DB-624 (30 m × 0.53 mm i.d., 3.00μm film thickness) column was used. The inlet split ratio was 5:1. The influ-encing factors in the chromatographic separation of the analytes were determined through a fractional factorial experimental design. Significant variables: the initial temperature (IT), the final temperature (FT) of the oven and the carrier gas flow rate (F) were optimized using a central composite design. Response transformation and desirability function were applied to find out the optimal combination of the chromatographic variables to achieve an adequate resolution of the analytes and short analysis time. These conditions were 30 °C for IT, 158 °C for FT and 1.90 mL/min for F. The method was proven to be accurate, linear in a wide range and very sensitive for the analyzed solvents through a comprehensive validation according to the ICH guidelines.

  14. Determination of tetrachloroethylene and other volatile halogenated organic compounds in oil wastes by headspace SPME GC-MS

    Energy Technology Data Exchange (ETDEWEB)

    Fabbri, D.; Bezzi, R.; Torri, C.; Galletti, P.; Tagliavini, E. [Bologna Univ., Ravenna (Italy). Lab. of Chemistry, C.I.R.S.A

    2007-09-15

    Oil wastes and slops are complex mixtures of hydrocarbons, which may contain a variety of contaminants including tetrachloroethylene (perchloroethylene, PCE) and other volatile halogenated organic compounds (VHOCs). The analytical determination of PCE at trace levels in petroleum-derived matrices is difficult to carry out in the presence of large amounts of hydrocarbon matrix components. In the following study, we demonstrate that headspace solid-phase microextraction (HS-SPME) combined with GC-MS analysis can be applied for the rapid measurement of PCE concentration in oil samples. The HS-SPME method was developed using liquid paraffin as matrix matching reference material for external and internal calibration and optimisation of experimental parameters. The limit of quantitation was 0.05 mg kg{sup -1}, and linearity was established up to 25 mg kg{sup -1}. The HS-SPME method was extended to several VHOCs, including trichloroethylene (TCE) in different matrices and was applied to the quantitative analysis of PCE and TCE in real samples.

  15. Method and apparatus for pyrolysis--porous layer open tubular column--cryoadsorption headspace sampling and analysis.

    Science.gov (United States)

    Bruno, Thomas J; Nichols, Jessica E

    2013-04-19

    In previous work, dynamic headspace vapor collection on short, porous layer open tubular (PLOT) capillary columns maintained at low temperature was introduced. In this paper, that metrology is extended with the introduction of a small in situ pyrolysis platform that provides for rapid heating and rapid vapor capture for a wide variety of samples. The new approach is referred to as pyro-PLOT-cryo. The pyrolysis platform is made from two small copper lead wires that hold a basket formed from small diameter, high resistance stainless steel or NiCr wire. The basket is formed to accept a small sample, the mass of which can typically range from 0.2 to 0.05 mg. The pyrolysis is performed by use of a resistor capacitor circuit of the type used in spot welders. We have provided examples of the application of this technique with the analysis of facial cosmetics, plastic explosives, organometallic gasoline additives, polymers, and in micro scale chemical reactions. Additional modifications and future work are also discussed.

  16. Liquid-solid sample preparation followed by headspace solid-phase microextraction determination of multiclass pesticides in soil.

    Science.gov (United States)

    Durović, Rada D; Dordević, Tijana M; Santrić, Ljiljana R

    2012-01-01

    This paper describes development and validation of a multiresidue method for the determination of five pesticides (terbufos, prochloraz, chloridazon, pendimethalin, and fluorochloridone) belonging to different pesticide groups in soil samples by GC/MS, followed by its application in the analysis of some agricultural soil samples. The method is based on a headspace solid-phase microextraction method. Microextraction conditions, namely temperature, extraction time, and NaCI content, were tested and optimized using a 100 microm polydimethylsiloxane fiber. Three extraction solvents [methanol, methanol-acetone (1 + 1, v/v), and methanol-acetone-hexane (2 + 2 + 1, v/v/v)] and the optimum number of extraction steps within the sample preparation stage were optimized for the extraction procedure. LOD values for all the studied compounds were less than 12 microg/kg. Recovery values for multiple analyses of soil samples fortified at 30 microg/kg of each pesticide were higher than 64%. The method was proven to be repeatable, with RSD lower than 15%.

  17. A robust method for determining water-extractable alkylphenol polyethoxylates in textile products by reaction-based headspace gas chromatography.

    Science.gov (United States)

    Zhang, Shu-Xin; Chai, Xin-Sheng; Huang, Bo-Xi; Mai, Xiao-Xia

    2015-08-07

    Alkylphenol polyethoxylates (APEO), surfactants used in the production of textiles, have the potential to move from the fabric to the skin of the person wearing the clothes, posing an inherent risk of adverse health consequences. Therefore, the textile industry needs a fast, robust method for determining aqueous extractable APEO in fabrics. The currently-favored HPLC methods are limited by the presence of a mixture of analytes (due to the molecular weight distribution) and a lack of analytical standards for quantifying results. As a result, it has not been possible to reach consensus on a standard method for the determination of APEO in textiles. This paper addresses these limitations through the use of reaction-based head space-gas chromatography (HS-GC). Specifically, water is used to simulate body sweat and extract APEO. HI is then used to react the ethoxylate chains to depolymerize the chains into iodoethane that is quantified through HS-GC, providing an estimate of the average amount of APEO in the clothing. Data are presented to justify the optimal operating conditions; i.e., water extraction at 60°C for 1h and reaction with a specified amount of HI in the headspace vial at 135°C for 4h. The results show that the HS-GC method has good precision (RSDtextile and related materials. As such, the method should be a strong candidate to become a standard method for such determinations.

  18. Analysis of Volatile Components of Adenosma indianum (Lour. Merr. by Steam Distillation and Headspace Solid-Phase Microextraction

    Directory of Open Access Journals (Sweden)

    Zhi Zeng

    2013-01-01

    Full Text Available The essential oil of Adenosma indianum (Lour. Merr. plays an important role in its antibacterial and antiphlogistic activities. In this work, the volatile components were extracted by steam distillation (SD and headspace solid-phase microextraction (HS-SPME and analysed by gas chromatography-mass spectrometry (GC-MS. A total of 49 volatile components were identified by GC-MS, and the major volatile components were α-limonene (20.59–35.07%, fenchone (15.79–31.81%, α-caryophyllene (6.98–10.32%, β-caryophyllene (6.98–10.19%, and piperitenone oxide (1.96–11.63%. The comparison of the volatile components from A. indianum (Lour. Merr. grown in two regions of China was reported. Also, the comparison of the volatile components by SD and HS-SPME was discussed. The results showed that the major volatile components of A. indianum (Lour. Merr. from two regions of China were similar but varied with different extraction methods. These results were indicative of the suitability of HS-SPME method for simple, rapid, and solvent-free analysis of the volatile components of the medicinal plants.

  19. Development of a Direct Headspace Collection Method from Arabidopsis Seedlings Using HS-SPME-GC-TOF-MS Analysis

    Directory of Open Access Journals (Sweden)

    Kazuki Saito

    2013-04-01

    Full Text Available Plants produce various volatile organic compounds (VOCs, which are thought to be a crucial factor in their interactions with harmful insects, plants and animals. Composition of VOCs may differ when plants are grown under different nutrient conditions, i.e., macronutrient-deficient conditions. However, in plants, relationships between macronutrient assimilation and VOC composition remain unclear. In order to identify the kinds of VOCs that can be emitted when plants are grown under various environmental conditions, we established a conventional method for VOC profiling in Arabidopsis thaliana (Arabidopsis involving headspace-solid-phase microextraction-gas chromatography-time-of-flight-mass spectrometry (HS-SPME-GC-TOF-MS. We grew Arabidopsis seedlings in an HS vial to directly perform HS analysis. To maximize the analytical performance of VOCs, we optimized the extraction method and the analytical conditions of HP-SPME-GC-TOF-MS. Using the optimized method, we conducted VOC profiling of Arabidopsis seedlings, which were grown under two different nutrition conditions, nutrition-rich and nutrition-deficient conditions. The VOC profiles clearly showed a distinct pattern with respect to each condition. This study suggests that HS-SPME-GC-TOF-MS analysis has immense potential to detect changes in the levels of VOCs in not only Arabidopsis, but other plants grown under various environmental conditions.

  20. Determination of urinary ortho- and meta-cresol in humans by headspace SPME gas chromatography/mass spectrometry.

    Science.gov (United States)

    Fustinoni, Silvia; Mercadante, Rosa; Campo, Laura; Scibetta, Licia; Valla, Carla; Foà, Vito

    2005-03-25

    ortho-Cresol (o-C) and meta-cresol (m-C) are minor urinary metabolites of toluene, a widely used chemical with neurotoxicological properties. A new assay for their determination in human urine is here proposed. Urinary cresol sulphates and glucuronates are submitted to acid hydrolysis, urine is neutralized, added with o-cresols-d8, and analytes are sampled in the headspace of urine by SPME using a polydimethylsiloxane fiber. Analysis is performed by GC/MS using, for separation, either a SupelcoWax10 (for o-C) or a chiral CP Cresol (for o-C and m-C) column. The method is very specific, with a range of linearity 0-5.0 mg/l, within- and between-run precision, as coefficient of variation, <15% and <19%, limit of detection of 0.006 mg/l for o-C and 0.007 mg/l for m-C. The procedure is applied to the quantification of cresols in urine from workers exposed to toluene and from subjects belonging to the general population.

  1. Determination of lactones in wines by headspace solid-phase microextraction and gas chromatography coupled with mass spectrometry.

    Science.gov (United States)

    Pérez-Olivero, S J; Pérez-Pont, M L; Conde, J E; Pérez-Trujillo, J P

    2014-01-01

    Application of headspace solid-phase microextraction (HS-SPME) coupled with high-resolution gas chromatographic (HRGC) analysis was studied for determining lactones in wines. Six different SPME fibers were tested, and the influence of different factors such as temperature and time of desorption, ionic strength, time of extraction, content of sugar, ethanol, tannins and anthocyanins, and pH and influence of SO2 were studied. The proposed HS-SPME-GC method is an appropriate technique for the quantitative analysis of γ-butyrolactone, γ-hexalactone, trans-whiskey lactone, γ-octalactone, cis-whiskey lactone, γ-nonalactone, γ-decalactone, δ-decalactone, and γ-undecalactone in wines. Method reproducibility and repeatability ranged between 0.6 and 5.2% for all compounds. Detection limit for γ-butyrolactone was 0.17 mg/L and a few μg/L for the rest of the compounds. The optimized method has been applied to several wine samples.

  2. Headspace Hanging Drop Liquid Phase Microextraction and Gas Chromatography-Mass Spectrometry for the Analysis of Flavors from Clove Buds

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Mi Jin; Shin, Yeon Jae; Oh, Se Yeon; Kim, Nam Sun; Kim, Kun; Lee, Dong Sun [Seoul Women' s University, Seoul (Korea, Republic of)

    2006-02-15

    A novel sample pretreatment technique, headspace hanging drop liquid phase microextraction (HS-LPME) was studied and applied to the determination of flavors from solid clove buds by gas chromatography-mass spectrometry (GC-MS). Several parameters affecting on HS-LPME such as organic solvent drop volume, extraction time, extraction temperature and phase ratio were investigated. 1-Octanol was selected as the extracting solvent, drop size was fixed to 0.6 μL. 60 min extraction time at 25 .deg. C was chosen. HS-LPME has the good efficiency demonstrated by the higher partition equilibrium constant (K{sub lh}) values and concentration factor (CF) values. The limits of detection (LOD) were 1.5-3.2 ng. The amounts of eugenol, β-caryophyllene and eugenol acetate from the clove bud sample were 1.90 mg/g, 1.47 mg/g and 7.0 mg/g, respectively. This hanging drop based method is a simple, fast and easy sample enrichment technique using minimal solvent. HSLPME is an alternative sample preparation method for the analysis of volatile aroma compounds by GC-MS.

  3. Trace-Level Volatile Quantitation by DART-MS following Headspace Extraction - Optimization and Validation in Grapes.

    Science.gov (United States)

    Jastrzembski, Jillian A; Bee, Madeleine Y; Sacks, Gavin L

    2017-10-02

    Ambient Ionization - Mass Spectrometry (AI-MS) techniques like Direct Analysis in Real Time (DART) offer the potential for rapid quantitative analyses of trace volatiles in food matrices, but performance is generally limited by the lack of pre-concentration and extraction steps. The sensitivity and selectivity of AI-MS approaches can be improved through solid-phase microextraction (SPME) with appropriate thin-film geometries, e.g. solid phase mesh enhanced sorption from headspace (SPMESH). This work improves the SPMESH-DART-MS approach for use in food analyses, and validates the approach for trace volatile analysis for two compounds in real samples (grape macerates). SPMESH units prepared with different sorbent coatings were evaluated for their ability to extract a range of odor-active volatiles, with polydimethylsiloxane/divinylbenzene giving the most satisfactory results. In combination with high-resolution mass spectrometry (HRMS), detection limits for SPMESH-DART-MS under 4 ng/L in less than 30 s acquisition times could be achieved for some volatiles (3-isobutyl-2-methoxypyrazine (IBMP), β-damascenone). A comparison of SPMESH-DART-MS and SPME-GC-MS quantitation of linalool and IBMP demonstrates excellent agreement between the two methods using real grape samples (r2≥0.90), although linalool measurements appeared to also include isobaric interferences.

  4. Rapid Separation of Elemental Species by Fast Multicapillary Gas Chromatography with Multichannel Optical Spectrometry Detection following Headspace Solid Phase Microextraction

    Directory of Open Access Journals (Sweden)

    Jacek Giersz

    2015-05-01

    Full Text Available A method for conducting fast and efficient gas chromatography based on short multicapillaries in straight alignment combined with atomic emission detection was developed for field analysis. The strategy enables for speciation analysis of organometallic compounds. The analytes are simultaneously ethylated and preconcentrated on a solid phase microextraction (SPME fiber placed in the headspace over the sample for 25 min. The ethylated species are then completely separated and selectively quantified within 25 s under isothermal conditions. A new miniaturized speciation analyzer has been constructed and evaluated. The system consists of a GC injection port and a lab-made miniaturized GC unit directly coupled with miniaturized plasma excitation source. The emitted light is transferred via optical fiber and registered with a miniaturized charged coupled device (CCD based spectrometer. Working parameters for multicapillary column gas chromatography with atomic emission detector, including carrier gas flow rate, desorption temperature, and GC column temperature, were optimized to achieve good separation of analytes. Basic investigations of the fundamental properties of 5 cm-long multicapillary column, to evaluate its potential and limitations as a rapid separation unit, are presented. The adaptation of the technique for use with a SPME system and with a multichannel element-selective plasma-emission detector is highlighted.

  5. Classification of 7 monofloral honey varieties by PTR-ToF-MS direct headspace analysis and chemometrics.

    Science.gov (United States)

    Schuhfried, Erna; Sánchez del Pulgar, José; Bobba, Marco; Piro, Roberto; Cappellin, Luca; Märk, Tilmann D; Biasioli, Franco

    2016-01-15

    Honey, in particular monofloral varieties, is a valuable commodity. Here, we present proton transfer reaction-time of flight-mass spectrometry, PTR-ToF-MS, coupled to chemometrics as a successful tool in the classification of monofloral honeys, which should serve in fraud protection against mispresentation of the floral origin of honey. We analyzed 7 different honey varieties from citrus, chestnut, sunflower, honeydew, robinia, rhododendron and linden tree, in total 70 different honey samples and a total of 206 measurements. Only subtle differences in the profiles of the volatile organic compounds (VOCs) in the headspace of the different honeys could be found. Nevertheless, it was possible to successfully apply 6 different classification methods with a total correct assignment of 81-99% in the internal validation sets. The most successful methods were stepwise linear discriminant analysis (LDA) and probabilistic neural network (PNN), giving total correct assignments in the external validation sets of 100 and 90%, respectively. Clearly, PTR-ToF-MS/chemometrics is a powerful tool in honey classification.

  6. Second Order Kinetic Modeling of Headspace Solid Phase Microextraction of Flavors Released from Selected Food Model Systems

    Directory of Open Access Journals (Sweden)

    Jiyuan Zhang

    2014-09-01

    Full Text Available The application of headspace-solid phase microextraction (HS-SPME has been widely used in various fields as a simple and versatile method, yet challenging in quantification. In order to improve the reproducibility in quantification, a mathematical model with its root in psychological modeling and chemical reactor modeling was developed, describing the kinetic behavior of aroma active compounds extracted by SPME from two different food model systems, i.e., a semi-solid food and a liquid food. The model accounted for both adsorption and release of the analytes from SPME fiber, which occurred simultaneously but were counter-directed. The model had four parameters and their estimated values were found to be more reproducible than the direct measurement of the compounds themselves by instrumental analysis. With the relative standard deviations (RSD of each parameter less than 5% and root mean square error (RMSE less than 0.15, the model was proved to be a robust one in estimating the release of a wide range of low molecular weight acetates at three environmental temperatures i.e., 30, 40 and 60 °C. More insights of SPME behavior regarding the small molecule analytes were also obtained through the kinetic parameters and the model itself.

  7. Improvement of biohydrogen production from solid wastes by intermittent venting and gas flushing of batch reactors headspace.

    Science.gov (United States)

    Valdez-Vazquez, Idania; Ríos-Leal, Elvira; Carmona-Martínez, Alessandro; Muñoz-Páez, Karla M; Poggi-Varaldo, Héctor M

    2006-05-15

    Headspace of batch minireactors was intermittently vented and gas flushed with N2 in order to enhance H2 production (PH) by anaerobic consortia degrading organic solid wastes. Type of inocula (meso and thermophilic), induction treatment (heat-shock pretreatment, HSP, and acetylene, Ac), and incubation temperature (37 and 55 degrees C) were studied by means of a factorial design. On average, it was found that mesophilic incubation had the most significant positive effect on PH followed by treatment with Ac, although the units with the best performance (high values of PH, initial hydrogen production rate, and short lag time) were those HSP-induced units incubated at 37 degrees C (type of inocula was not significant). In this way, after 720 h of incubation PH was inhibited in those units by H2 partial pressure (pH2) of 0.54 atm. Venting and gas flushing with N2 was efficient to eliminate that inhibition achieving additional hydrogen generation in subsequent incubation cycles although smaller than the first one. Thus, four cycles of PH were obtained from the same substrate with neither addition of inocula nor application of induction treatment obtaining an increment of 100% in the generated H2. In those subsequent cycles there was a positive correlation between PH and organic acids/solvent ratio; maximum values were found in the first cycle. Solventogenesis could be clearly distinguished in third and fourth production cycles, probably due to a metabolic shift originated by high organic acid concentrations.

  8. Naphthalene emissions from moth repellents or toilet deodorant blocks determined using head-space and small-chamber tests

    Institute of Scientific and Technical Information of China (English)

    JO Wan-Kuen; LEE Jong-Hyo; LIM Ho-Jin; JEONG Woo-Sik

    2008-01-01

    The present study investigated the emissions of naphthalene and other compounds from several different moth repellents (MRs) and one toilet deodorant block (TDB) currently sold in Korea, using a headspace analysis. The emission factors and emission rates of naphthalene were studied using a small-scale environmental chamber. Paper-type products emitted a higher concentration of the total volatile organic compounds (VOCs) (normalized to the weight of test piece) than ball-type products, which in turn emitted higher concentration than a gel-type product. In contrast, naphthalene was either the most or the second highest abundant compound for the four ball products, whereas