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Sample records for 3c clamped downhole

  1. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2002-09-01

    Borehole seismology is the highest resolution geophysical imaging technique available to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This proposal takes direct aim at this shortcoming. P/GSI is developing a 400 level 3C clamped downhole seismic receiver array for borehole seismic 3D imaging. This array will remove the acquisition barrier to record the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for economic use of 3D borehole seismic imaging for reservoir characterization and monitoring. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore facilitate 9C reservoir imaging. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the fluid types. The data quality and the data volumes from a 400 level 3C array will allow us to develop the data processing technology necessary for high resolution reservoir imaging.

  2. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P Paulsson

    2002-05-01

    Borehole seismology is the highest resolution geophysical imaging technique available to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This proposal takes direct aim at this shortcoming. P/GSI is developing a 400 level 3C clamped downhole seismic receiver array for borehole seismic 3D imaging. This array will remove the acquisition barrier to record the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for economic use of 3D borehole seismic imaging for reservoir characterization and monitoring. By using 3C surface seismic or borehole seismic sources the 400 level receiver array will furthermore facilitate 9C reservoir imaging. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the fluid types. The data quality and the data volumes from a 400 level 3C array will allow us to develop the data processing technology necessary for high resolution reservoir imaging.

  3. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-12-31

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  4. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2005-03-31

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently hampered by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  5. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-06-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  6. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2002-12-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  7. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-05-31

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  8. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P Paulsson

    2003-09-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  9. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS.

    SciTech Connect

    Bjorn N.P Paulsson

    2003-01-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  10. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-09-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  11. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2003-12-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  12. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P Paulsson

    2003-07-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  13. DEVELOPMENT OF A 400 LEVEL 3C CLAMPED DOWNHOLE SEISMIC RECEIVER ARRAY FOR 3D BOREHOLE SEISMIC IMAGING OF GAS RESERVOIRS

    SciTech Connect

    Bjorn N.P. Paulsson

    2004-05-01

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of the rock and the

  14. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    SciTech Connect

    Bjorn N.P. Paulsson

    2005-08-21

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently hampered by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  15. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    SciTech Connect

    Bjorn N. P. Paulsson

    2005-09-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently hampered by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  16. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    SciTech Connect

    Bjorn N.P Paulsson

    2006-05-05

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently hampered by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver arrays will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging of the complex deep gas reservoirs and allow quantitative prediction of

  17. Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs

    SciTech Connect

    Bjorn N. P. Paulsson

    2006-09-30

    Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to perform high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology has been hampered by the lack of acquisition technology necessary to record large volumes of high frequency, high signal-to-noise-ratio borehole seismic data. This project took aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array has removed the technical acquisition barrier for recording the data volumes necessary to do high resolution 3D VSP and 3D cross-well seismic imaging. Massive 3D VSP{reg_sign} and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that promise to take the gas industry to the next level in their quest for higher resolution images of deep and complex oil and gas reservoirs. Today only a fraction of the oil or gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of detailed compartmentalization of oil and gas reservoirs. In this project, we developed a 400 level 3C borehole seismic receiver array that allows for economic use of 3D borehole seismic imaging for reservoir characterization and monitoring. This new array has significantly increased the efficiency of recording large data volumes at sufficiently dense spatial sampling to resolve reservoir complexities. The receiver pods have been fabricated and tested to withstand high temperature (200 C/400 F) and high pressure (25,000 psi), so that they can operate in wells up to 7,620 meters (25,000 feet) deep. The receiver array is deployed on standard production or drill tubing. In combination with 3C surface seismic or 3C borehole seismic sources, the 400

  18. Advanced downhole periodic seismic generator

    DOEpatents

    Hardee, Harry C.; Hills, Richard G.; Striker, Richard P.

    1991-07-16

    An advanced downhole periodic seismic generator system for transmitting variable frequency, predominantly shear-wave vibration into earth strata surrounding a borehole. The system comprises a unitary housing operably connected to a well head by support and electrical cabling and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a variable speed pneumatic oscillator and a self-contained pneumatic reservoir for producing a frequency-swept seismic output over a discrete frequency range.

  19. Downhole hydraulic seismic generator

    DOEpatents

    Gregory, Danny L.; Hardee, Harry C.; Smallwood, David O.

    1992-01-01

    A downhole hydraulic seismic generator system for transmitting energy wave vibrations into earth strata surrounding a borehole. The system contains an elongated, unitary housing operably connected to a well head aboveground by support and electrical cabling, and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a hydraulic oscillator containing a double-actuating piston whose movement is controlled by an electro-servovalve regulating a high pressure hydraulic fluid flow into and out of upper and lower chambers surrounding the piston. The spent hydraulic fluid from the hydraulic oscillator is stored and pumped back into the system to provide high pressure fluid for conducting another run at the same, or a different location within the borehole.

  20. Downhole tool adapted for telemetry

    DOEpatents

    Hall, David R.; Fox, Joe

    2010-12-14

    A cycleable downhole tool such as a Jar, a hydraulic hammer, and a shock absorber adapted for telemetry. This invention applies to other tools where the active components of the tool are displaced when the tool is rotationally or translationally cycled. The invention consists of inductive or contact transmission rings that are connected by an extensible conductor. The extensible conductor permits the transmission of the signal before, after, and during the cycling of the tool. The signal may be continuous or intermittent during cycling. The invention also applies to downhole tools that do not cycle, but in operation are under such stress that an extensible conductor is beneficial. The extensible conductor may also consist of an extensible portion and a fixed portion. The extensible conductor also features clamps that maintain the conductor under stresses greater than that seen by the tool, and seals that are capable of protecting against downhole pressure and contamination.

  1. Downhole tool

    DOEpatents

    Hall, David R.; Muradov, Andrei; Pixton, David S.; Dahlgren, Scott Steven; Briscoe, Michael A.

    2007-03-20

    A double shouldered downhole tool connection comprises box and pin connections having mating threads intermediate mating primary and secondary shoulders. The connection further comprises a secondary shoulder component retained in the box connection intermediate a floating component and the primary shoulders. The secondary shoulder component and the pin connection cooperate to transfer a portion of makeup load to the box connection. The downhole tool may be selected from the group consisting of drill pipe, drill collars, production pipe, and reamers. The floating component may be selected from the group consisting of electronics modules, generators, gyroscopes, power sources, and stators. The secondary shoulder component may comprises an interface to the box connection selected from the group consisting of radial grooves, axial grooves, tapered grooves, radial protrusions, axial protrusions, tapered protrusions, shoulders, and threads.

  2. Post clamp

    NASA Technical Reports Server (NTRS)

    Ramsey, John K. (Inventor); Meyn, Erwin H. (Inventor)

    1990-01-01

    A pair of spaced collars are mounted at right angles on a clamp body by retaining rings which enable the collars to rotate with respect to the clamp body. Mounting posts extend through aligned holes in the collars and clamp body. Each collar can be clamped onto the inserted post while the clamp body remains free to rotate about the post and collar. The clamp body is selectively clamped onto each post.

  3. Rigid clamp

    DOEpatents

    Benavides, G.L.; Burt, J.D.

    1994-07-12

    The invention relates to a clamp mechanism that can be used to attach or temporarily support objects inside of tubular goods. The clamp mechanism can also be modified so that it grips objects. The clamp has a self-centering feature to accommodate out-of-roundness or other internal defections in tubular objects such as pipe. A plurality of clamping shoes are expanded by a linkage which is preferably powered by a motor to contact the inside of a pipe. The motion can be reversed and jaw elements can be connected to the linkage so as to bring the jaws together to grab an object. 12 figs.

  4. Rigid clamp

    DOEpatents

    Benavides, Gilbert L.; Burt, Jack D.

    1994-01-01

    The invention relates to a clamp mechanism that can be used to attach or temporarily support objects inside of tubular goods. The clamp mechanism can also be modified so that it grips objects. The clamp has a self-centering feature to accommodate out-of-roundness or other internal defections in tubular objects such as pipe. A plurality of clamping shoes are expanded by a linkage which is preferably powered by a motor to contact the inside of a pipe. The motion can be reversed and jaw elements can be connected to the linkage so as to bring the jaws together to grab an object.

  5. Downhole Dynamometer Data Processor

    Energy Science and Technology Software Center (ESTSC)

    1996-08-19

    The Downhole Dynamometer Database contains data taken during tests made on a number of different wells using both a surface dynamometer and a number of different downhole dynamometer tools. DOWNDYN allows the user to perform four different functions on the database: select a data file, choose information from the file, and either plot or export that information.

  6. Downhole telemetry system

    DOEpatents

    Normann, R.A.; Kadlec, E.R.

    1994-11-08

    A downhole telemetry system is described for optically communicating to the surface operating parameters of a drill bit during ongoing drilling operations. The downhole telemetry system includes sensors mounted with a drill bit for monitoring at least one operating parameter of the drill bit and generating a signal representative thereof. The downhole telemetry system includes means for transforming and optically communicating the signal to the surface as well as means at the surface for producing a visual display of the optically communicated operating parameters of the drill bit. 7 figs.

  7. Downhole telemetry system

    DOEpatents

    Normann, Randy A.; Kadlec, Emil R.

    1994-01-01

    A downhole telemetry system is described for optically communicating to the surface operating parameters of a drill bit during ongoing drilling operations. The downhole telemetry system includes sensors mounted with a drill bit for monitoring at least one operating parameter of the drill bit and generating a signal representative thereof. The downhole telemetry system includes means for transforming and optically communicating the signal to the surface as well as means at the surface for producing a visual display of the optically communicated operating parameters of the drill bit.

  8. Charlie's Clamp.

    ERIC Educational Resources Information Center

    Tarino, Janet Z.

    1998-01-01

    Presents a version of the crush-the-can demonstration which is a hands-on activity in which students use an inexpensive, easily made holder for the can called Charlie's clamp. Includes some suggestions for the follow-up discussion. (DDR)

  9. Downhole steam quality measurement

    DOEpatents

    Lee, David O.; Montoya, Paul C.; Muir, James F.; Wayland, Jr., J. Robert

    1987-01-01

    An empirical method for the remote sensing of steam quality that can be easily adapted to downhole steam quality measurements by measuring the electrical properties of two-phase flow across electrode grids at low frequencies.

  10. Downhole Data Transmission System

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Fox, Joe

    2004-04-06

    A system for transmitting data through a string of down-hole components. In accordance with one aspect, the system includes a plurality of downhole components, such as sections of pipe in a drill string. Each downhole component includes a pin end and a box end, with the pin end of one downhole component being adapted to be connected to the box end of another. Each pin end includes external threads and an internal pin face distal to the external threads. Each box end includes an internal shoulder face with internal threads distal to the internal shoulder face. The internal pin face and the internal shoulder face are aligned with and proximate each other when the pin end of the one component is threaded into a box end of the other component.

  11. CORCO downhole steam generator

    SciTech Connect

    Rintoul, B.

    1982-03-01

    The opening of a new frontier in steaming moved forward in Jan. 1982 when a CORCO (Chemical Oil Recovery Co.) generator described as the first commercial down-hole steam generator went into operation in Kern County's Devils Den field, 60 miles northwest of Bakersfield, CA. A major reason for selecting the down-hole generator for the Devils Den field is that along with steam the unit puts away flue gas resulting from combustion. There is no pressure to speak of in the escudo, and it is hoped that the inert gas will build up bottom-hole pressure to assist in oil recovery. Another reason is that the down-hole generator, rated for 7 million btu/hr, makes it possible to tailor steam injection to the well's requirements. The advantages and disadvantages of the CORCO generator are described, along with its application in the Kern River field.

  12. Three phase downhole separator process

    DOEpatents

    Cognata, Louis John

    2008-06-24

    Three Phase Downhole Separator Process (TPDSP) is a process which results in the separation of all three phases, (1) oil, (2) gas, and (3) water, at the downhole location in the well bore, water disposal injection downhole, and oil and gas production uphole.

  13. Distributed downhole drilling network

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Fox, Joe; Pixton, David S.

    2006-11-21

    A high-speed downhole network providing real-time data from downhole components of a drilling strings includes a bottom-hole node interfacing to a bottom-hole assembly located proximate the bottom end of a drill string. A top-hole node is connected proximate the top end of the drill string. One or several intermediate nodes are located along the drill string between the bottom-hole node and the top-hole node. The intermediate nodes are configured to receive and transmit data packets transmitted between the bottom-hole node and the top-hole node. A communications link, integrated into the drill string, is used to operably connect the bottom-hole node, the intermediate nodes, and the top-hole node. In selected embodiments, a personal or other computer may be connected to the top-hole node, to analyze data received from the intermediate and bottom-hole nodes.

  14. Downhole transmission system

    DOEpatents

    Hall, David R.; Fox, Joe

    2008-01-15

    A transmission system in a downhole component comprises a data transmission element in both ends of the downhole component. Each data transmission element houses an electrically conducting coil in a MCEI circular trough. An electrical conductor connects both the transmission elements. The electrical conductor comprises at least three electrically conductive elements insulated from each other. In the preferred embodiment the electrical conductor comprises an electrically conducting outer shield, an electrically conducting inner shield and an electrical conducting core. In some embodiments of the present invention, the electrical conductor comprises an electrically insulating jacket. In other embodiments, the electrical conductor comprises a pair of twisted wires. In some embodiments, the electrical conductor comprises semi-conductive material.

  15. Downhole pressure attenuation apparatus

    SciTech Connect

    Ricles, T.D.; Barton, J.A.

    1992-02-18

    This patent describes a process for preventing damage to tool strings and other downhole equipment in a well caused by pressures produced during detonation of one or more downhole explosive devices. It comprises adding to a tool string at least one pressure attenuating apparatus for attenuating the peak pressure wave and quasi-static pressure pulse produced by the explosive devices, the pressure attenuating apparatus including an initially closed relief vent including tubing means supporting a plurality of charge port assemblies each including an explosive filled shaped charge and a prestressed disc, the shaped charges interconnected by a detonating cord, the amount of explosive in each shaped charge being sufficient to rupture its associated disc without damaging surrounding tubular bodies in the well, and a vent chamber defined by the tubing means and providing a liquid free volume, and opening the relief vent substantially contemporaneously with downhole explosive device detonation by detonating the shaped charges to rupture the discs of the charge port assemblies.

  16. Downhole Fluid Analyzer Development

    SciTech Connect

    Bill Turner

    2006-11-28

    A novel fiber optic downhole fluid analyzer has been developed for operation in production wells. This device will allow real-time determination of the oil, gas and water fractions of fluids from different zones in a multizone or multilateral completion environment. The device uses near infrared spectroscopy and induced fluorescence measurement to unambiguously determine the oil, water and gas concentrations at all but the highest water cuts. The only downhole components of the system are the fiber optic cable and windows. All of the active components--light sources, sensors, detection electronics and software--will be located at the surface, and will be able to operate multiple downhole probes. Laboratory testing has demonstrated that the sensor can accurately determine oil, water and gas fractions with a less than 5 percent standard error. Once installed in an intelligent completion, this sensor will give the operating company timely information about the fluids arising from various zones or multilaterals in a complex completion pattern, allowing informed decisions to be made on controlling production. The research and development tasks are discussed along with a market analysis.

  17. Clamp usable as jig and lifting clamp

    DOEpatents

    Tsuyama, Yoshizo

    1976-01-01

    There is provided a clamp which is well suited for use as a lifting clamp for lifting and moving materials of assembly in a shipyard, etc. and as a pulling jig in welding and other operations. The clamp comprises a clamp body including a shackle for engagement with a pulling device and a slot for receiving an article, and a pair of jaws provided on the leg portions of the clamp body on the opposite sides of the slot to grip the article in the slot, one of said jaws consisting of a screw rod and the other jaw consisting of a swivel jaw with a spherical surface, whereby when the article clamped in the slot by the pair of jaws tends to slide in any direction with respect to the clamp body, the article is more positively gripped by the pair of jaws.

  18. Downhole steam injector

    DOEpatents

    Donaldson, A. Burl; Hoke, Donald E.

    1983-01-01

    An improved downhole steam injector has an angled water orifice to swirl the water through the device for improved heat transfer before it is converted to steam. The injector also has a sloped diameter reduction in the steam chamber to throw water that collects along the side of the chamber during slant drilling into the flame for conversion to steam. In addition, the output of the flame chamber is beveled to reduce hot spots and increase efficiency, and the fuel-oxidant inputs are arranged to minimize coking.

  19. Method and system for downhole clock synchronization

    DOEpatents

    Hall, David R.; Bartholomew, David B.; Johnson, Monte; Moon, Justin; Koehler, Roger O.

    2006-11-28

    A method and system for use in synchronizing at least two clocks in a downhole network are disclosed. The method comprises determining a total signal latency between a controlling processing element and at least one downhole processing element in a downhole network and sending a synchronizing time over the downhole network to the at least one downhole processing element adjusted for the signal latency. Electronic time stamps may be used to measure latency between processing elements. A system for electrically synchronizing at least two clocks connected to a downhole network comprises a controlling processing element connected to a synchronizing clock in communication over a downhole network with at least one downhole processing element comprising at least one downhole clock. Preferably, the downhole network is integrated into a downhole tool string.

  20. Downhole pulse tube refrigerators

    SciTech Connect

    Swift, G.; Gardner, D.

    1997-12-01

    This report summarizes a preliminary design study to explore the plausibility of using pulse tube refrigeration to cool instruments in a hot down-hole environment. The original motivation was to maintain Dave Reagor`s high-temperature superconducting electronics at 75 K, but the study has evolved to include three target design criteria: cooling at 30 C in a 300 C environment, cooling at 75 K in a 50 C environment, cooling at both 75 K and 30 C in a 250 C environment. These specific temperatures were chosen arbitrarily, as representative of what is possible. The primary goals are low cost, reliability, and small package diameter. Pulse-tube refrigeration is a rapidly growing sub-field of cryogenic refrigeration. The pulse tube refrigerator has recently become the simplest, cheapest, most rugged and reliable low-power cryocooler. The authors expect this technology will be applicable downhole because of the ratio of hot to cold temperatures (in absolute units, such as Kelvin) of interest in deep drilling is comparable to the ratios routinely achieved with cryogenic pulse-tube refrigerators.

  1. Downhole heat exchangers

    SciTech Connect

    Culver, G.; Lund, J.W.

    1999-09-01

    The downhole heat exchanger (DHE) eliminates the problem of disposal of geothermal fluid, since only heat is taken from the well. The exchanger consists of a system of pipes or tubes suspended in the well through which clean secondary water is pumped or allowed to circulate by natural convection. These systems offer substantial economic savings over surface heat exchangers where a single-well system is adequate (typically less than 0.8 MWt, with well depths up to about 500 ft) and may be economical under certain conditions at well depths to 1500 ft. Several designs have proven successful; but, the most popular are a simple hairpin loop or multiple loops of iron pipe (similar to the tubes in a U-tube and shell exchanger) extending to near the well bottom. An experimental design consisting of multiple small tubes with headers at each end suspended just below the water surface appears to offer economic and heating capacity advantages. The paper describes design and construction details and New Zealand`s experience with downhole heat exchangers.

  2. Drilling jar for use in a downhole network

    DOEpatents

    Hall, David R.; Fox, Joe; McPherson, James; Pixton, David S.; Briscoe, Michael

    2006-01-31

    Apparatus and methods for integrating transmission cable into the body of selected downhole tools, such as drilling jars, having variable or changing lengths. A wired downhole-drilling tool is disclosed in one embodiment of the invention as including a housing and a mandrel insertable into the housing. A coiled cable is enclosed within the housing and has a first end connected to the housing and a second end connected to the mandrel. The coiled cable is configured to stretch and shorten in accordance with axial movement between the housing and the mandrel. A clamp is used to fix the coiled cable with respect to the housing, the mandrel, or both, to accommodate a change of tension in the coiled cable.

  3. Downhole steam quality measurement

    DOEpatents

    Lee, D.O.; Montoya, P.C.; Muir, J.F.; Wayland, J.R. Jr.

    1985-06-19

    The present invention relates to an empirical electrical method for remote sensing of steam quality utilizing flow-through grids which allow measurement of the electrical properties of a flowing two-phase mixture. The measurement of steam quality in the oil field is important to the efficient application of steam assisted recovery of oil. Because of the increased energy content in higher quality steam it is important to maintain the highest possible steam quality at the injection sandface. The effectiveness of a steaming operation without a measure of steam quality downhole close to the point of injection would be difficult to determine. Therefore, a need exists for the remote sensing of steam quality.

  4. Downhole data transmission system

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S; Dahlgren, Scott; Fox, Joe

    2006-06-20

    A system for transmitting data through a string of downhole components. In one aspect, the system includes first and second magnetically conductive, electrically insulating elements at both ends of the component. Each element includes a first U-shaped trough with a bottom, first and second sides and an opening between the two sides. Electrically conducting coils are located in each trough. An electrical conductor connects the coils in each component. In operation, a varying current applied to a first coil in one component generates a varying magnetic field in the first magnetically conductive, electrically insulating element, which varying magnetic field is conducted to and thereby produces a varying magnetic field in the second magnetically conductive, electrically insulating element of a connected component, which magnetic field thereby generates a varying electrical current in the second coil in the connected component.

  5. Downhole Data Transmission System

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Fox, Joe

    2003-12-30

    A system for transmitting data through a string of downhole components. In one aspect, the system includes first and second magnetically conductive, electrically insulating elements at both ends of the component. Each element includes a first U-shaped trough with a bottom, first and second sides and an opening between the two sides. Electrically conducting coils are located in each trough. An electrical conductor connects the coils in each component. In operation, a varying current applied to a first coil in one component generates a varying magnetic field in the first magnetically conductive, electrically insulating element, which varying magnetic field is conducted to and thereby produces a varying magnetic field in the second magnetically conductive, electrically insulating element of a connected component, which magnetic field thereby generates a varying electrical current in the second coil in the connected component.

  6. Force-Measuring Clamp

    NASA Technical Reports Server (NTRS)

    Nunnelee, Mark (Inventor)

    2004-01-01

    A precision clamp that accurately measures force over a wide range of conditions is described. Using a full bridge or other strain gage configuration. the elastic deformation of the clamp is measured or detected by the strain gages. Thc strain gages transmit a signal that corresponds to the degree of stress upon the clamp. Thc strain gage signal is converted to a numeric display. Calibration is achieved by ero and span potentiometers which enable accurate measurements by the force-measuring clamp.

  7. Downhole steam generator shows merit

    SciTech Connect

    Not Available

    1980-11-01

    Production from a 5-spot pattern in Kern River Field reached 25,000 bbl during a 5-month test of a down-hole steam generator-equivalent to the amount of oil expected if steam injection from the conventional source had been continued. The test evaluated the down-hole generator as a steam source relatively free of atmospheric pollutants. The biggest objection to steam recovery of heavy crude is the volume of combustion products vented to the atmosphere, and these frequently contain small amounts of sulfur compounds. One big advantage of generating steam down hole is elimination of heat losses in the injection well. The practical limit for conventional steam injection is in a reservoir approximately 2,500 ft deep; the down-hole generator should operate economically to 6,000 ft. The test proved the feasibility of the method, and cleared the way for a series of down-hole generator installation and retrieval tests.

  8. Photovoltaic panel clamp

    DOEpatents

    Mittan, Margaret Birmingham; Miros, Robert H. J.; Brown, Malcolm P.; Stancel, Robert

    2012-06-05

    A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.

  9. Photovoltaic panel clamp

    DOEpatents

    Brown, Malcolm P.; Mittan, Margaret Birmingham; Miros, Robert H. J.; Stancel, Robert

    2013-03-19

    A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.

  10. Radial wedge flange clamp

    DOEpatents

    Smith, Karl H.

    2002-01-01

    A radial wedge flange clamp comprising a pair of flanges each comprising a plurality of peripheral flat wedge facets having flat wedge surfaces and opposed and mating flat surfaces attached to or otherwise engaged with two elements to be joined and including a series of generally U-shaped wedge clamps each having flat wedge interior surfaces and engaging one pair of said peripheral flat wedge facets. Each of said generally U-shaped wedge clamps has in its opposing extremities apertures for the tangential insertion of bolts to apply uniform radial force to said wedge clamps when assembled about said wedge segments.

  11. Transducer for downhole drilling components

    DOEpatents

    Hall, David R; Fox, Joe R

    2006-05-30

    A robust transmission element for transmitting information between downhole tools, such as sections of drill pipe, in the presence of hostile environmental conditions, such as heat, dirt, rocks, mud, fluids, lubricants, and the like. The transmission element maintains reliable connectivity between transmission elements, thereby providing an uninterrupted flow of information between drill string components. A transmission element is mounted within a recess proximate a mating surface of a downhole drilling component, such as a section of drill pipe. The transmission element may include an annular housing forming a trough, an electrical conductor disposed within the trough, and an MCEI material disposed between the annular housing and the electrical conductor.

  12. Reusable thermal cycling clamp

    NASA Technical Reports Server (NTRS)

    Debnam, W. J., Jr.; Fripp, A. L.; Crouch, R. K. (Inventor)

    1985-01-01

    A reusable metal clamp for retaining a fused quartz ampoule during temperature cycling in the range of 20 deg C to 1000 deg C is described. A compressible graphite foil having a high radial coefficient of thermal expansion is interposed between the fused quartz ampoule and metal clamp to maintain a snug fit between these components at all temperature levels in the cycle.

  13. Quick action clamp

    NASA Technical Reports Server (NTRS)

    Calco, Frank S. (Inventor)

    1991-01-01

    A quick release toggle clamp that utilizes a spring that requires a deliberate positive action for disengagement is presented. The clamp has a sliding bolt that provides a latching mechanism. The bolt is moved by a handle that tends to remain in an engaged position while under tension.

  14. Downhole steam generation: material studies

    SciTech Connect

    Beauchamp, E.K.; Weirick, L.J.; Muir, J.F.

    1982-01-01

    One enhanced oil recovery technique for extracting heavy crude from deep reservoirs by steam at the bottom of an injection well. Development of a downhole steam generator that will produce steam and inject it into formations at depths greater than 2500 feet is one objective of a Department of Energy/Sandia National Laboratories development effort - Project DEEP STEAM. Extensive material studies have been performed in support of Project DEEP STEAM; current efforts are devoted primarily to the selection and evaluation of materials for use in downhole steam generators. This paper presents observations of the performance of candidate metals and refractory ceramics (combustor liners) during tests of two prototypic, high pressure, diesel/air combustion, direct contact, downhole steam generators. The first downhole test of such a generator provides data on the performance of various metals (304L, 310 and 316S stainless steels and plain carbon steel) exposed for several weeks to a warm, aerated saltwater environment. A number of corrosion mechanisms acted to cause severely degraded perforance of some of the metals. Several refractory liner designs were evaluated during ground level tests of a generator having a ceramic-lined combustion chamber. Of the two refractories employed, alumina and silicon carbide, the alumina liners exhibited more serious surface degradation and corrosion.

  15. West Flank Downhole Temperature Data

    DOE Data Explorer

    Doug Blankenship

    2008-03-01

    Downhole temperature data for the three wells inside the West Flank FORGE footprint; 83-11, TCH 74-2 and TCH 48-11. TCH 74-2 and TCH 48-11 were both collected before 1990 and 83-11 was collected in 2009. The are compiled into one spreadsheet for ease of visualization.

  16. Battery switch for downhole tools

    DOEpatents

    Boling, Brian E.

    2010-02-23

    An electrical circuit for a downhole tool may include a battery, a load electrically connected to the battery, and at least one switch electrically connected in series with the battery and to the load. The at least one switch may be configured to close when a tool temperature exceeds a selected temperature.

  17. Laser beam guard clamps

    DOEpatents

    Dickson, Richard K.

    2010-09-07

    A quick insert and release laser beam guard panel clamping apparatus having a base plate mountable on an optical table, a first jaw affixed to the base plate, and a spring-loaded second jaw slidably carried by the base plate to exert a clamping force. The first and second jaws each having a face acutely angled relative to the other face to form a V-shaped, open channel mouth, which enables wedge-action jaw separation by and subsequent clamping of a laser beam guard panel inserted through the open channel mouth. Preferably, the clamping apparatus also includes a support structure having an open slot aperture which is positioned over and parallel with the open channel mouth.

  18. A monogenean without clamps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ectoparasites face a daily challenge: to remain attached to their host. Polyopisthocotylean monogeneans attach to the surface of fish gills by highly specialized structures, the sclerotized clamps. In the original description of the protomicrocotylid species Lethacotyle fijiensis, described 50 years...

  19. Downhole steam generator having a downhole oxidant compressor

    DOEpatents

    Fox, R.L.

    1981-01-07

    Am improved apparatus is described for the downhole injection of steam into boreholes, for tertiary oil recovery. It includes an oxidant supply, a fuel supply, an igniter, a water supply, an oxidant compressor, and a combustor assembly. The apparatus is designed for efficiency, preheating of the water, and cooling of the combustion chamber walls. The steam outlet to the borehole is provided with pressure-responsive doors for closing the outlet in response to flameout. (DLC)

  20. Sperm Patch-Clamp

    PubMed Central

    Lishko, Polina; Clapham, David E.; Navarro, Betsy; Kirichok, Yuriy

    2014-01-01

    Sperm intracellular pH and calcium concentration ([Ca2+]i) are two central factors that control sperm activity within the female reproductive tract. As such, the ion channels of the sperm plasma membrane that alter intracellular sperm [Ca2+] and pH play important roles in sperm physiology and the process of fertilization. Indeed, sperm ion channels regulate sperm motility, control sperm chemotaxis toward the egg in some species, and may trigger the acrosome reaction. Until recently, our understanding of these important molecules was rudimentary due to the inability to patch-clamp spermatozoa and directly record the activity of these ion channels under voltage clamp. Recently, we overcame this technical barrier and developed a method for reproducible application of the patch-clamp technique to mouse and human spermatozoa. This chapter covers important aspects of application of the patch-clamp technique to spermatozoa, such as selection of the electrophysiological equipment, isolation of spermatozoa for patch-clamp experiments, formation of the gigaohm seal with spermatozoa, and transition into the whole-cell mode of recording. We also discuss potential pitfalls in application of the patch-clamp technique to flagellar ion channels. PMID:23522465

  1. Direct firing downhole steam generator

    SciTech Connect

    Wagner, W.R.; Wright, D.E.; Binsley, R.L.

    1982-06-29

    A direct firing down-hole steam generator is composed of an injector assembly axially connected with a combustion chamber. Downstream of the combustion chamber and oriented so as to receive its output is a heat exchanger where preheated water is injected into the heat exchanger through a number of one-way valves. The heated water is vaporized and injected through a nozzle, packer, and check valve into the well formation. 9 claims.

  2. Clamp for arctic pipeline support

    SciTech Connect

    Morton, A.W.

    1988-11-29

    This patent describes a ring clamp for supporting and anchoring a large diameter metallic arctic pipeline comprising substantially rigid, curved clamp portions adapted to completely encircle the pipeline and fastening means connecting the clamp portions, the clamp portions having inner and outer layers of fiber reinforced rigid polymer material and an intermediate core layer of honeycomb-form aramid paper.

  3. Downhole component with a pressure equalization passageway

    DOEpatents

    Hall, David R.; Pixton, David S.; Dahlgren, Scott; Reynolds, Jay T.; Breihan, James W.; Briscoe, Michael A.

    2006-08-22

    The present invention includes a downhole component adapted for transmitting downhole data. The downhole component includes a threaded end on a downhole component. The threaded end furthermore includes an interior region, and exterior region, and a mating surface wherein a cavity is formed. A data transmission element is disposed in the cavity and displaces a volume of the cavity. At least one passageway is formed in the threaded region between interior and exterior regions. The passageway is in fluid communication with both the interior and exterior regions and thereby relieves pressure build up of thread lubricant upon tool joint make up.

  4. Corrosion reference for geothermal downhole materials selection

    SciTech Connect

    Ellis, P.F. II, Smith, C.C.; Keeney, R.C.; Kirk, D.K.; Conover, M.F.

    1983-03-01

    Geothermal downhole conditions that may affect the performance and reliability of selected materials and components used in the drilling, completion, logging, and production of geothermal wells are reviewed. The results of specific research and development efforts aimed at improvement of materials and components for downhole contact with the hostile physicochemical conditions of the geothermal reservoir are discussed. Materials and components covered are tubular goods, stainless steels and non-ferrous metals for high-temperature downhole service, cements for high-temperature geothermal wells, high-temperature elastomers, drilling and completion tools, logging tools, and downhole pumps. (MHR)

  5. Clamping characteristics study on different types of clamping unit

    SciTech Connect

    Jiao, Zhiwei; Liu, Haichao; Xie, Pengcheng; Yang, Weimin

    2015-05-22

    Plastic products are becoming more and more widely used in aerospace, IT, digital electronics and many other fields. With the development of technology, the requirement of product precision is getting higher and higher. However, type and working performance of clamping unit play a decisive role in product precision. Clamping characteristics of different types of clamping unit are discussed in this article, which use finite element numerical analysis method through the software ABAQUS to study the clamping uniformity, and detect the clamping force repeatability precision. The result shows that compared with toggled three-platen clamping unit, clamping characteristics of internal circulation two-platen clamping unit are better, for instance, its mold cavity deformation and force that bars and mold parting surface suffered are more uniform, and its clamping uniformity and repeatability precision is also better.

  6. Clamp for detonating fuze

    NASA Technical Reports Server (NTRS)

    Holderman, E. J.

    1968-01-01

    Quick acting clamp provides physical support for a closely confined detonating fuse in an application requiring removal and replacement at frequent intervals during test. It can be designed with a base of any required strength and configuration to permit the insertion of an object.

  7. Downhole steam generator having a downhole oxidant compressor

    DOEpatents

    Fox, Ronald L.

    1983-01-01

    Apparatus and method for generation of steam in a borehole for penetration into an earth formation wherein a downhole oxidant compressor is used to compress relatively low pressure (atmospheric) oxidant, such as air, to a relatively high pressure prior to mixing with fuel for combustion. The multi-stage compressor receives motive power through a shaft driven by a gas turbine powered by the hot expanding combustion gases. The main flow of compressed oxidant passes through a velocity increasing nozzle formed by a reduced central section of the compressor housing. An oxidant bypass feedpipe leading to peripheral oxidant injection nozzles of the combustion chamber are also provided. The downhole compressor allows effective steam generation in deep wells without need for high pressure surface compressors. Feedback preheater means are provided for preheating fuel in a preheat chamber. Preheating of the water occurs in both a water feed line running from aboveground and in a countercurrent water flow channel surrounding the combustor assembly. The countercurrent water flow channels advantageously serve to cool the combustion chamber wall. The water is injected through slotted inlets along the combustion chamber wall to provide an unstable boundary layer and stripping of the water from the wall for efficient steam generation. Pressure responsive doors are provided at the steam outlet for closing and sealing the combustion chamber from entry of reservoir fluids in the event of a flameout.

  8. Downhole steam generator having a downhole oxidant compressor

    SciTech Connect

    Fox, R.L.

    1983-04-19

    Apparatus and method for generation of steam in a borehole for penetration into an earth formation wherein a downhole oxidant compressor is used to compress relatively low pressure (Atmospheric) oxidant, such as air, to a relatively high pressure prior to mixing with fuel for combustion. The multi-stage compressor receives motive power through a shaft driven by a gas turbine powered by the hot expanding combustion gases. The main flow of compressed oxidant passes through a velocity increasing nozzle formed by a reduced central section of the compressor housing. An oxidant bypass feedpipe leading to peripheral oxidant injection nozzles of the combustion chamber are also provided. The downhole compressor allows effective steam generation in deep wells without need for high pressure surface compressors. Feedback preheater means are provided for preheating fuel in a preheat chamber. Preheating of the water occurs in both a water feed line running from aboveground and in a countercurrent water flow channel surrounding the combustor assembly. The countercurrent water flow channels advantageously serve to cool the combustion chamber wall. The water is injected through slotted inlets along the combustion chamber wall to provide an unstable boundary layer and stripping of the water from the wall for efficient steam generation. Pressure responsive doors are provided at the steam outlet for closing and sealing the combustion chamber from entry of reservoir fluids in the event of a flameout.

  9. Downhole material injector for lost circulation control

    DOEpatents

    Glowka, David A.

    1994-01-01

    Apparatus and method for simultaneously and separately emplacing two streams of different materials through a drillstring in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drillstring at the desired downhole location and harden only after mixing for control of a lost circulation zone.

  10. Downhole material injector for lost circulation control

    DOEpatents

    Glowka, D.A.

    1991-01-01

    This invention is comprised of an apparatus and method for simultaneously and separately emplacing two streams of different materials through a drillstring in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drillstring at the desired downhole location and harden only after mixing for control of a lost circulation zone.

  11. Downhole material injector for lost circulation control

    DOEpatents

    Glowka, D.A.

    1994-09-06

    Apparatus and method are disclosed for simultaneously and separately emplacing two streams of different materials through a drill string in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drill string at the desired downhole location and harden only after mixing for control of a lost circulation zone. 6 figs.

  12. Harsh environments electronics : downhole applications.

    SciTech Connect

    Vianco, Paul Thomas

    2011-03-01

    The development and operational sustainment of renewable (geothermal) and non-renewable (fossil fuel) energy resources will be accompanied by increasingly higher costs factors: exploration and site preparation, operational maintenance and repair. Increased government oversight in the wake of the Gulf oil spill will only add to the cost burden. It is important to understand that downhole conditions are not just about elevated temperatures. It is often construed that military electronics are exposed to the upper limit in terms of extreme service environments. Probably the harshest of all service conditions for electronics and electrical equipment are those in oil, gas, and geothermal wells. From the technology perspective, advanced materials, sensors, and microelectronics devices are benefificial to the exploration and sustainment of energy resources, especially in terms of lower costs. Besides the need for the science that creates these breakthroughs - there is also a need for sustained engineering development and testing. Downhole oil, gas, and geothermal well applications can have a wide range of environments and reliability requirements: Temperature, Pressure, Vibration, Corrosion, and Service duration. All too frequently, these conditions are not well-defifined because the application is labeled as 'high temperature'. This ambiguity is problematic when the investigation turns to new approaches for electronic packaging solutions. The objective is to develop harsh environment, electronic packaging that meets customer requirements of cost, performance, and reliability. There are a number of challenges: (1) Materials sets - solder alloys, substrate materials; (2) Manufacturing process - low to middle volumes, low defect counts, new equipment technologies; and (3) Reliability testing - requirements documents, test methods and modeling, relevant standards documents. The cost to develop and sustain renewable and non-renewable energy resources will continue to escalate

  13. Development of the downhole dynamometer database

    SciTech Connect

    Waggoner, J.R.; Mansure, A.

    1997-02-01

    The Downhole Dynamometer Database is a compilation of test data collected with a set of five downhole tools built by Albert Engineering under contract to Sandia National Laboratories. The downhole dynamometer tools are memory tools deployed in the sucker rod string with sensors to measure pressure, temperature, load, and acceleration. The acceleration data is processed to yield position, so that a load vs. position dynagraph can be generated using data collected downhole. With five tools in the hole at one time, all measured data and computed dynagraphs from five different positions in the rod string are available. The purpose of the Database is to provide industry with a complete and high quality measurement of downhole sucker rod pumping dynamics. To facilitate use of the database, Sandia has developed a Microsoft Windows-based interface that functions as a visualizer and browser to the more than 40 MBytes of data. The interface also includes a data export feature to allow users to extract data from the database for use in their own programs. This paper includes a description of the downhole dynamometer tools, data collection program, database content, and a few illustrations of the data contained in the downhole dynamometer database.

  14. Cantilever clamp fitting

    NASA Technical Reports Server (NTRS)

    Melton, Patrick B. (Inventor)

    1989-01-01

    A device is disclosed for sealing and clamping a cylindrical element which is to be attached to an object such as a wall, a pressurized vessel or another cylindrical element. The device includes a gland having an inner cylindrical wall, which is threaded at one end and is attached at a bendable end to a deformable portion, which in turn is attached to one end of a conical cantilever structure. The other end of the cantilever structure connects at a bendable area to one end of an outer cylindrical wall. The opposite end of cylindrical wall terminates in a thickened portion, the radially outer surface of which is adapted to accommodate a tool for rotating the gland. The terminal end of cylindrical wall also includes an abutment surface, which is adapted to engage a seal, which in turn engages a surface of a receiver. The receiver further includes a threaded portion for engagement with the threaded portion of gland whereby a tightening rotation of gland relative to receiver will cause relative movement between cylindrical walls and of gland. This movement causes a rotation of the conical structure and thus a bending action at bending area and at the bending end of the upper end of inner cylindrical wall. These rotational and bending actions result in a forcing of the deformable portion radially inwardly so as to contact and deform a pipe. This forcible contact creates a seal between gland and pipe, and simultaneously clamps the pipe in position.

  15. Energy harvesting under excitation of clamped-clamped beam

    NASA Astrophysics Data System (ADS)

    Batra, Ashok; Alomari, Almuatasim; Aggarwal, Mohan; Bandyopadhyay, Alak

    2016-04-01

    In this article, a piezoelectric energy harvesting has been developed experimentally and theoretically based on Euler- Bernoulli Theory. A PVDF piezoelectric thick film has attached along of clamped-clamped beam under sinusoidal base excitation of shaker. The results showed a good agreement between the experimental and simulation of suggested model. The voltage output frequency response function (FRF), current FRF, and output power has been studied under short and open circuit conditions at first vibration mode. The mode shape of the clamped-clamped beam for first three resonance frequency has been modeled and investigated using COMSOL Multiphysics and MATLAB.

  16. Hand-Held Power Clamp

    NASA Technical Reports Server (NTRS)

    Clancy, J. P.

    1985-01-01

    Tool furnishes large pushing or pulling forces. Device includes two clamping blocks, two clamping plates, and a motor-driven linear actuator with selflocking screw shaft. Power clamp exerts opening or closing force at push of switch. Tool approximately 1 m long. Originally designed to secure payload aboard Space Shuttle, operated with one hand to apply opening or closing force of up to 1,000 lb (4,400 N). Clamp has potential applications as end effector for industrial robots and in rescue work to push or pull wreckage with great force.

  17. Downhole steam generator: field tests

    SciTech Connect

    Eson, R.L.

    1982-01-01

    Excessive air pollution and heat losses up to 32% in the surface lines and out the stacks of conventional generators are reasons why conventional steam generation is efficient. These problems are addressed and overcome through the use of a direct-fired down-hole steam generator (DSG). By performing the combustion process at high pressure, and then adding water, a mixture of carbon dioxide, nitrogen, and steam is discharged directly into the heavy oil reservoir. This study documents a series of field tests of a direct-fired DSG showing its ability to produce and inject high quality steam into heavy oil reservoirs without the need for expensive stack scrubbers to remove sulfur dioxide (SO/sub 2/), as well as sophisticated nitrogen oxides (NO/sub x/) control techniques. Results from the 6-in. diameter, 6-ft long, 7.1-mmBtu/hr DSG showed that corrosion can be controlled and production can be improved dramatically in actual field tests in California heavy oil reservoirs.

  18. New downhole steam generator tested

    SciTech Connect

    Bleakley, W.B.

    1981-07-01

    Completion of 2 field tests of a new-model down-hole steam generator paves the way for further evaluation and development of a system destined to increase California's heavy oil production. Current air pollution restrictions there prevent installation of conventional steam generators in several areas of interest to oil operators. The current series of tests, conducted by Chemical Oil Recovery Co. (CORCO) of Bakersfield, California, follows an earlier prototype operation conducted by Sandia National Laboratories in conjunction with the US Department of Energy. The CORCO tests were conducted on the surface with the generator's output going into Tenneco Oil Exploration and Production Co.'s overland-Riokern Well No. 80, located in the Kern River field 4 miles north of Bakersfield. The first test was concluded with just under 1000 bbl of steam injected, less than planned due to a higher-than-expected injection pressure. The unit operated at less than 25% capacity because of the air compressor limitation. Compressor output was only 285 psi, not enough to inject the desired volumes into the reservoir. Test data shows that injection amounted to 150 bpd of 90 to 95% quality steam at 225-psi wellhead pressure. After injection, the well was shut in for 3 days to allow soaking, then put on production. Initial production was 40 bopd at 175 F.

  19. DHE (downhole heat exchangers). [Downhole Heat Exchangers (DHE)

    SciTech Connect

    Culver, G.

    1990-11-01

    The use of downhole heat exchangers (DHE) for residential or commercial space and domestic water heating and other applications has several desirable features. Systems are nearly or completely passive -- that is, no or very little geothermal water or steam is produced from the well either reducing or completely eliminating surface environmental concerns and the need for disposal systems or injection wells. Initial cost of pumps and installation are eliminated or reduced along with pumping power costs and maintenance costs associated with pumping often corrosive geothermal fluids. Many residential and small commercial systems do not require circulating pumps because the density difference in the incoming and outgoing sides of the loop are sufficient to overcome circulating friction losses in the entire system. The major disadvantage of DHEs is their dependence on natural heat flow. In areas where geological conditions provide high permeability and a natural hydraulic gradient, DHEs can provide a substantial quantity of heat. A single 500-ft (152 m) well in Klamath Falls, Oregon, supplies over one megawatt thermal and output is apparently limited by the surface area of pipe that can be installed in the well bore. In contrast, DHEs used in conjunction with heat pumps may supply less than 8 KW from a well of similar depth. Here output is limited by conductive heat flow with perhaps a small contribution from convection near the well bore. The highest capacity DHE reported to date, in Turkey, supplies 6 MW thermal from an 820-ft (250 m) well. There were two main goals for this project. The first was to gather, disseminate and exchange internationally information on DHES. The second was to perform experiments that would provide insight into well bore/aquifer interaction and thereby provide more information on which to base DHE designs. 27 refs., 31 figs., 3 tabs.

  20. DOWNHOLE VIBRATION MONITORING & CONTROL SYSTEM

    SciTech Connect

    Martin E. Cobern

    2004-10-13

    The deep hard rock drilling environment induces severe vibrations into the drillstring, which can cause reduced rates of penetration (ROP) and premature failure of the equipment. The only current means of controlling vibration under varying conditions is to change either the rotary speed or the weight-on-bit (WOB). These changes often reduce drilling efficiency. Conventional shock subs are useful in some situations, but often exacerbate the problems. The objective of this project is development of a unique system to monitor and control drilling vibrations in a ''smart'' drilling system. This system has two primary elements: (1) The first is an active vibration damper (AVD) to minimize harmful axial, lateral and torsional vibrations. The hardness of this damper will be continuously adjusted using a robust, fast-acting and reliable unique technology. (2) The second is a real-time system to monitor drillstring vibration, and related parameters. This monitor adjusts the damper according to local conditions. In some configurations, it may also send diagnostic information to the surface via real-time telemetry. The AVD is implemented in a configuration using magnetorheological (MR) fluid. By applying a current to the magnetic coils in the damper, the viscosity of the fluid can be changed rapidly, thereby altering the damping coefficient in response to the measured motion of the tool. Phase I of this program entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype. Phase I of the project was completed by the revised end date of May 31, 2004. The objectives of this phase were met, and all prerequisites for Phase II have been completed. The month of June, 2004 was primarily occupied with the writing of the Phase I Final Report, the sole deliverable of Phase I, which will be submitted in the next quarter. Redesign of the laboratory prototype and design of the downhole (Phase II) prototype was begun.

  1. 275 C Downhole Microcomputer System

    SciTech Connect

    Chris Hutchens; Hooi Miin Soo

    2008-08-31

    An HC11 controller IC and along with serial SRAM and ROM support ICs chip set were developed to support a data acquisition and control for extreme temperature/harsh environment conditions greater than 275 C. The 68HC11 microprocessor is widely used in well logging tools for control, data acquisition, and signal processing applications and was the logical choice for a downhole controller. This extreme temperature version of the 68HC11 enables new high temperature designs and additionally allows 68HC11-based well logging tools and MWD tools to be upgraded for high temperature operation in deep gas reservoirs, The microcomputer chip consists of the microprocessor ALU, a small boot ROM, 4 kbyte data RAM, counter/timer unit, serial peripheral interface (SPI), asynchronous serial interface (SCI), and the A, B, C, and D parallel ports. The chip is code compatible with the single chip mode commercial 68HC11 except for the absence of the analog to digital converter system. To avoid mask programmed internal ROM, a boot program is used to load the microcomputer program from an external mask SPI ROM. A SPI RAM IC completes the chip set and allows data RAM to be added in 4 kbyte increments. The HC11 controller IC chip set is implemented in the Peregrine Semiconductor 0.5 micron Silicon-on-Sapphire (SOS) process using a custom high temperature cell library developed at Oklahoma State University. Yield data is presented for all, the HC11, SPI-RAM and ROM. The lessons learned in this project were extended to the successful development of two high temperature versions of the LEON3 and a companion 8 Kbyte SRAM, a 200 C version for the Navy and a 275 C version for the gas industry.

  2. Operational experiences of a downhole steam generator

    NASA Astrophysics Data System (ADS)

    Marshall, B. W.

    The US Department of Energy supported the development of downhole steam generators for enhanced oil recovery as a part of Project DEEP STEAM. A final step in the development program was to deploy a downhole steam generator in the field to demonstrate its reliable operation and to evaluate the effect of the combined steam/exhaust products effluent on the reservoir. Sandia National Laboratories entered into an agreement with the City of Long Beach to place two direct contact, high pressure combustors in the Wilmington Field in Long Beach, California. These units one downhole and the other on the surface, have now been operated for a few months and gas communication with the production wells measured. The operational experience of this field experiment are discussed.

  3. Operational experiences of a downhole steam generator

    SciTech Connect

    Marshall, B.W.

    1982-01-01

    The US Department of Energy has supported the development of downhole steam generators for enhanced oil recovery as a part of Project DEEP STEAM. A final step in the development program was to deploy a downhole steam generator (DHSG) in the field to demonstrate its reliable operation and to evaluate the effect of the combined steam/exhaust products effluent on the reservoir. Sandia National Laboratories entered into an agreement with the City of Long Beach to place two direct contact, high pressure combustors in the Wilmington Field in Long Beach, California. These units one downhole and the other on the surface, have now been operated for a few months and gas communication with the production wells measured. The operational experience of this field experiment are discussed.

  4. Parameters affecting downhole pH

    SciTech Connect

    Garber, J.D.; Jangama, V.R.; Willmon, J.

    1997-09-01

    The presence of acetic and formic acids in the produced water of gas condensate wells has been known for some time by the industry. In traditional water analysis, it has been titrated and reported as alkalinity. The calculation of accurate downhole pH values requires that these ions be analyzed separately in the water and that an organic acid material balance be performed on all three phases in the separator. In this manner, it is then possible to use phase distribution coefficients involving ionic equilibrium to determine how these acids distribute themselves between phases as the pH calculation proceeds downhole. In this paper, the above method of calculation of pH and {Delta}pH is used to examine the effect that various concentrations of these acids have on the downhole pH. Various concentrations of acids are examined, and two cases are calculated in which the effect of condensate on the pH is examined.

  5. Loaded transducer for downhole drilling components

    DOEpatents

    Hall, David R.; Fox, Joe; Daly, Jeffery E.

    2009-05-05

    A system for transmitting information between downhole components has a first downhole component with a first mating surface and a second downhole component having a second mating surface configured to substantially mate with the first mating surface. The system also has a first transmission element with a first communicating surface and is mounted within a recess in the first mating surface. The first transmission element also has an angled surface. The recess has a side with multiple slopes for interacting with the angled surface, each slope exerting a different spring force on the first transmission element. A second transmission element has a second communicating surface mounted proximate the second mating surface and adapted to communicate with the first communicating surface.

  6. Dual-cone double-helical downhole logging device

    DOEpatents

    Yu, Jiunn S.

    1984-01-01

    A broadband downhole logging device includes a double-helix coil wrapped over a dielectric support and surrounded by a dielectric shield. The device may also include a second coil longitudinally aligned with a first coil and enclosed within the same shield for measuring magnetic permeability of downhole formations and six additional coils for accurately determining downhole parameters.

  7. Downhole pump unseating apparatus and method

    SciTech Connect

    Burrows, M.L.

    1991-04-09

    This patent describes a fluid producing borehole having a downhole pump assembly located at a lower end of a tubing string for producing fluid from a pay zone, wherein some parts of the pump assembly are affixed to a hold-down and the hold-down is telescopingly received in sealed relationship within a seating nipple, the combination with the pump assembly of an apparatus for unsticking a downhole pump assembly by pushing the hold-down in an uphole direction and thereby forcing the hold-down to become unseated from the seating nipple.

  8. Loaded Transducer Fpr Downhole Drilling Component

    DOEpatents

    Hall, David R.; Hall, H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Briscoe, Michael; Fox, Joe

    2005-07-05

    A robust transmission element for transmitting information between downhole tools, such as sections of drill pipe, in the presence of hostile environmental conditions, such as heat, dirt, rocks, mud, fluids, lubricants, and the like. The transmission element maintains reliable connectivity between transmission elements, thereby providing an uninterrupted flow of information between drill string components. A transmission element is mounted within a recess proximate a mating surface of a downhole drilling component, such as a section of drill pipe. To close gaps present between transmission elements, transmission elements may be biased with a "spring force," urging them closer together.

  9. Loaded transducer for downhole drilling components

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Briscoe, Michael A.; Dahlgren, Scott Steven; Fox, Joe; Sneddon, Cameron

    2006-02-21

    A robust transmission element for transmitting information between downhole tools, such as sections of drill pipe, in the presence of hostile environmental conditions, such as heat, dirt, rocks, mud, fluids, lubricants, and the like. The transmission element maintains reliable connectivity between transmission elements, thereby providing an uninterrupted flow of information between drill string components. A transmission element is mounted within a recess proximate a mating surface of a downhole drilling component, such as a section of drill pipe. To close gaps present between transmission elements, transmission elements may be biased with a "spring force, urging them closer together."

  10. Downhole Elemental Analysis with LIBS

    NASA Technical Reports Server (NTRS)

    Moreschini, Paolo; Zacny, Kris; Rickman, Doug

    2011-01-01

    vertical stage; a second actuator at the top of the downhole probe allows radial scanning of the borehole. Analysis of iron and titanium in lunar simulant with LIBS was performed in air using the method of standard addition. The results for lunar simulant NU-LHT-2M show a value for the concentration of iron ranging between 2.29% and 3.05% depending on the atomic line selected. The accepted value for the sample analyzed is 2.83%, showing the capability for the system in development to provide qualitative and semi-quantitative analysis in real-time.

  11. Downhole elemental analysis with LIBS

    NASA Astrophysics Data System (ADS)

    Moreschini, P.; Zacny, K.; Rickman, D.

    2011-12-01

    top of the downhole probe allows radial scanning of the borehole. Analysis of iron and titanium in lunar simulant with LIBS was performed in air using the method of standard addition. The results for lunar simulant NU-LHT-2M show a value for the concentration of iron ranging between 2.29% and 3.05% depending on the atomic line selected. The accepted value for the sample analyzed is 2.83%, showing the capability for the system in development to provide qualitative and semi-quantitative analysis in real-time.

  12. Internal V-Band Clamp

    DOEpatents

    Vaughn, Mark R.; Hafenrichter, Everett S.; Chapa, Agapito C.; Harris, Steven M.; Martinez, Marcus J.; Baty, Roy S.

    2006-02-28

    A system for clamping two tubular members together in an end-to-end relationship uses a split ring with a V-shaped outer rim that can engage a clamping surface on each member. The split ring has a relaxed closed state where the ends of the ring are adjacent and the outside diameter of the split ring is less than the minimum inside diameter of the members at their ends. The members are clamped when the split ring is spread into an elastically stretched position where the ring rim is pressed tightly against the interior surfaces of the members. Mechanisms are provided for removing the spreader so the split ring will return to the relaxed state, releasing the clamped members.

  13. Development of PDC Bits for Downhole Motors

    SciTech Connect

    Karasawa, H.; Ohno, T.

    1995-01-01

    To develop polycrystalline hamond compact (PDC) bits of the full-face type which can be applied to downhole motor drilling, drilling tests for granite and two types of andesite were conducted using bits with 98.43 and 142.88 mm diameters. The bits successfully drilled these types of rock at rotary speeds from 300 to 400 rpm.

  14. Remote down-hole well telemetry

    DOEpatents

    Briles, Scott D.; Neagley, Daniel L.; Coates, Don M.; Freund, Samuel M.

    2004-07-20

    The present invention includes an apparatus and method for telemetry communication with oil-well monitoring and recording instruments located in the vicinity of the bottom of gas or oil recovery pipes. Such instruments are currently monitored using electrical cabling that is inserted into the pipes; cabling has a short life in this environment, and requires periodic replacement with the concomitant, costly shutdown of the well. Modulated reflectance, a wireless communication method that does not require signal transmission power from the telemetry package will provide a long-lived and reliable way to monitor down-hole conditions. Normal wireless technology is not practical since batteries and capacitors have to frequently be replaced or recharged, again with the well being removed from service. RF energy generated above ground can also be received, converted and stored down-hole without the use of wires, for actuating down-hole valves, as one example. Although modulated reflectance reduces or eliminates the loss of energy at the sensor package because energy is not consumed, during the transmission process, additional stored extra energy down-hole is needed.

  15. Expandable Metal Liner For Downhole Components

    DOEpatents

    Hall, David R.; Fox, Joe R.

    2004-10-05

    A liner for an annular downhole component is comprised of an expandable metal tube having indentations along its surface. The indentations are formed in the wall of the tube either by drawing the tube through a die, by hydroforming, by stamping, or roll forming and may extend axially, radially, or spirally along its wall. The indentations accommodate radial and axial expansion of the tube within the downhole component. The tube is inserted into the annular component and deformed to match an inside surface of the component. The tube may be expanded using a hydroforming process or by drawing a mandrel through the tube. The tube may be expanded in such a manner so as to place it in compression against the inside wall of the component. The tube is useful for improving component hydraulics, shielding components from contamination, inhibiting corrosion, and preventing wear to the downhole component during use. It may also be useful for positioning conduit and insulated conductors within the component. An insulating material may be disposed between the tube and the component in order to prevent galvanic corrosion of the downhole component.

  16. Lifting clamp positively grips structural shapes

    NASA Technical Reports Server (NTRS)

    Reinhardt, E. C.

    1966-01-01

    Welded steel clamps securely grip structural shapes of various sizes for crane operations. The clamp has adjustable clamping jaws and screw-operated internal v-jaws and provides greater safety than hoisting slings presently used. The structural member can be rotated in any manner, angle, or direction without being released by the clamp.

  17. Split-tapered joint clamping device

    DOEpatents

    Olsen, Max J.; Schwartz, Jr., John F.

    1988-01-01

    This invention relates to a clamping device for removably attaching a tool element to a bracket element wherein a bracket element is disposed in a groove in the tool and a clamping member is disposed in said groove and in engagement with a clamping face of the bracket and a wall of the groove and with the clamping member having pivot means engaging the bracket and about which the clamping member rotates.

  18. Feasibility evaluation of a downhole steam generator

    SciTech Connect

    Wright, D.E.; Binsley, R.L.

    1982-04-01

    A discussion is presented of a downhole steam generator (DHSG); benefits and features are described. The work was done under the management of Sandia Laboratories as part of the U.S. DOE's Project Deep Steam. The effort began with a comparison of alternate ways of generating steam downhole. The most economical was found to be the indirect system, where heat from low-pressure (approximately 5-atm (500-kPal))combustion of fuel oil and air is transferred to high pressure water. A feasibility test unit was constructed and tested extensively; results are described. Comparative economic analyses indicate that the DHSG is competitive with conventional systems even at moderate depths. Below 2,500 ft (762 m) it is a clear choice. 3 refs.

  19. Downhole steam generator at Kern River

    SciTech Connect

    Rintoul, B.

    1980-05-01

    Testing of a prototype down-hole steam generator for use in enhanced oil recovery (EOR) operations has begun at a heavy oil reservoir in the Kern River oil field in California. Steam and combustion gases are directed into an 800-ft-deep reservoir through a standard surface steam delivery system, although the system is designed to function at depths to 4500 ft. Present steam injection techniques require one-third of the oil recovered to be used to fuel the injection system, and the boilers require scrubbers to control emissions to specifications. The down-hole system is expected to use only 2/3 as much fuel as the conventional systems and to have less impact on air quality.

  20. Development of a downhole steam generator system

    SciTech Connect

    Not Available

    1984-04-01

    This report describes the development of a downhole steam generator system for use in enhanced oil recovery. The system is composed of four major components: A state-of-the-art review indicated that advances in technology would be necessary in two areas (high pressure combustion and high temperature packer seals) in order to fabricate a field-worthy system. As a result, two tasks were undertaken which resulted in the development of a novel ceramic-lined combustor and a unique all-metal packer. These elements were incorporated into an overall system design. Key system components were built and tested in the laboratory. The program culminated in a successful simulated downhole test of the entire system, less tube string, at Sandia National Laboratories. 5 references, 41 figures, 9 tables.

  1. Downhole transmission system comprising a coaxial capacitor

    DOEpatents

    Hall, David R.; Pixton, David S.; Johnson, Monte L.; Bartholomew, David B.; Hall, Jr., H. Tracy; Rawle, Michael

    2011-05-24

    A transmission system in a downhole component comprises a plurality of data transmission elements. A coaxial cable having an inner conductor and an outer conductor is disposed within a passage in the downhole component such that at least one capacitor is disposed in the passage and having a first terminal coupled to the inner conductor and a second terminal coupled to the outer conductor. Preferably the transmission element comprises an electrically conducting coil. Preferably, within the passage a connector is adapted to electrically connect the inner conductor of the coaxial cable and the lead wire. The coaxial capacitor may be disposed between and in electrically communication with the connector and the passage. In another embodiment a connector is adapted to electrical connect a first and a second portion of the inner conductor of the coaxial cable and a coaxial capacitor is in electrical communication with the connector and the passage.

  2. Polished Downhole Transducer Having Improved Signal Coupling

    DOEpatents

    Hall, David R.; Fox, Joe

    2006-03-28

    Apparatus and methods to improve signal coupling in downhole inductive transmission elements to reduce the dispersion of magnetic energy at the tool joints and to provide consistent impedance and contact between transmission elements located along the drill string. A transmission element for transmitting information between downhole tools is disclosed in one embodiment of the invention as including an annular core constructed of a magnetically conductive material. The annular core forms an open channel around its circumference and is configured to form a closed channel by mating with a corresponding annular core along an annular mating surface. The mating surface is polished to provide improved magnetic coupling with the corresponding annular core. An annular conductor is disposed within the open channel.

  3. Data transmission element for downhole drilling components

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Fox, Joe; Sneddon, Cameron; Briscoe, Michael

    2006-01-31

    A robust data transmission element for transmitting information between downhole components, such as sections of drill pipe, in the presence of hostile environmental conditions, such as heat, dirt, rocks, mud, fluids, lubricants, and the like. The data transmission element components include a generally U-shaped annular housing, a generally U-shaped magnetically conductive, electrically insulating element such as ferrite, and an insulated conductor. Features on the magnetically conducting, electrically insulating element and the annular housing create a pocket when assembled. The data transmission element is filled with a polymer to retain the components within the annular housing by filling the pocket with the polymer. The polymer can bond with the annular housing and the insulated conductor but preferably not the magnetically conductive, electrically insulating element. A data transmission element is mounted within a recess proximate a mating surface of a downhole drilling component, such as a section of drill pipe.

  4. Downhole pipe selection for acoustic telemetry

    DOEpatents

    Drumheller, D.S.

    1995-12-19

    A system is described for transmitting signals along a downhole string including a plurality of serially connected tubular pipes such as drill or production pipes, a transmitter for transmitting a signal along the string and a receiver for receiving the signal placed along the string at a location spaced from said transmitting means, wherein the pipes between the transmitter and the receiver are ordered according to length of tube to minimize loss of signal from said transmitter to said receiver. 7 figs.

  5. Downhole pipe selection for acoustic telemetry

    DOEpatents

    Drumheller, Douglas S.

    1995-01-01

    A system for transmitting signals along a downhole string including a plurality of serially connected tubular pipes such as drill or production pipes, a transmitter for transmitting a signal along the string and a receiver for receiving the signal placed along the string at a location spaced from said transmitting means, wherein the pipes between the transmitter and the receiver are ordered according to length of tube to minimize loss of signal from said transmitter to said receiver.

  6. Downhole drilling network using burst modulation techniques

    DOEpatents

    Hall; David R. , Fox; Joe

    2007-04-03

    A downhole drilling system is disclosed in one aspect of the present invention as including a drill string and a transmission line integrated into the drill string. Multiple network nodes are installed at selected intervals along the drill string and are adapted to communicate with one another through the transmission line. In order to efficiently allocate the available bandwidth, the network nodes are configured to use any of numerous burst modulation techniques to transmit data.

  7. How to Assess the Quality of Glucose Clamps? Evaluation of Clamps Performed With ClampArt, a Novel Automated Clamp Device

    PubMed Central

    Benesch, Carsten; Heise, Tim; Klein, Oliver; Heinemann, Lutz; Arnolds, Sabine

    2015-01-01

    Background: There are no widely accepted parameters to assess the quality of glucose clamps. Thus, we selected different parameters describing clamp quality. These parameters were then evaluated in glucose clamps carried out with ClampArt, a novel CE-marked, state-of-the-art fully automated glucose clamp device employing continuous blood glucose (BG) measurements and minute-by-minute adaptations of glucose infusion rate (GIR). Methods: Thirty-nine glucose clamps were performed in 10 healthy and 29 subjects with type 1 diabetes (T1DM) (total duration 583 h). ClampArt-based BG measurements were compared with those obtained with a laboratory reference method. Clamp quality was assessed by 5 parameters: (1) difference (mg/dl) of all paired BG measurements of ClampArt versus reference method (“trueness”), (2) coefficient of variation (CV, %) of ClampArt’s BG measurements at target clamp level (“precision”), (3) mean absolute relative difference (MARD, %) at target clamp level (“accuracy”), (4) difference (mg/dl) between ClampArt and target BG (“control deviation”), and (5) percentage operational time (“utility”). Results: ClampArt-based BG measurements showed a trueness of 1.2 ± 2.5 mg/dl. CV and MARD at target BG were 5.5 ± 2.1% and 5.3 ± 2.3%, respectively. There were only small deviations from target level (1.2 ± 1.6 mg/dl). Operational time was as high as 95.4% ± 4.1% (means ± SD). Conclusions: The selected parameters seem to be adequate to characterize clamp quality. The novel, fully automated clamp device ClampArt achieves high clamp quality, which in future trials should be compared with other (automated and manual) clamp methods. PMID:25852075

  8. Method and apparatus of assessing down-hole drilling conditions

    DOEpatents

    Hall, David R.; Pixton, David S.; Johnson, Monte L.; Bartholomew, David B.; Fox, Joe

    2007-04-24

    A method and apparatus for use in assessing down-hole drilling conditions are disclosed. The apparatus includes a drill string, a plurality of sensors, a computing device, and a down-hole network. The sensors are distributed along the length of the drill string and are capable of sensing localized down-hole conditions while drilling. The computing device is coupled to at least one sensor of the plurality of sensors. The data is transmitted from the sensors to the computing device over the down-hole network. The computing device analyzes data output by the sensors and representative of the sensed localized conditions to assess the down-hole drilling conditions. The method includes sensing localized drilling conditions at a plurality of points distributed along the length of a drill string during drilling operations; transmitting data representative of the sensed localized conditions to a predetermined location; and analyzing the transmitted data to assess the down-hole drilling conditions.

  9. Downhole Seismic Monitoring at the Geysers

    SciTech Connect

    Rutledge, J.T.; Anderson, T.D.; Fairbanks, T.D.; Albright, J.N.

    1999-10-17

    A 500-ft length, 6-level, 3-component, vertical geophone array was permanently deployed within the upper 800 ft of Unocal's well GDCF 63-29 during a plug and abandonment operation on April 7, 1998. The downhole array remains operational after a period of 1 year, at a temperature of about 150 C. Continuous monitoring and analysis of shallow seismicity (<4000 ft deep) has been conducted over that same 1-year period. The downhole array was supplemented with 4 surface stations in late-1998 and early-1999 to help constrain locations of shallow seismicity. Locations occurring within about 1 km ({approximately}3000 ft) of the array have been determined for a subset of high-frequency events detected on the downhole and surface stations for the 10-week period January 6 to March 16, 1999. These events are distinct from surface-monitored seismicity at The Geysers in that they occur predominantly above the producing reservoir, at depths ranging from about 1200 to 4000 ft depth (1450 to -1350 ft elevation). The shallow seismicity shows a northeast striking trend, similar to seismicity trends mapped deeper within the reservoir and the strike of the predominant surface lineament observed over the productive field.

  10. Emission controller for indirect fired downhole steam generators

    SciTech Connect

    Vrolyk, J. J.

    1985-02-12

    The present invention provides an indirect downhole steam generator system comprising a downhole combustor, a well casing which provides a flue for the exhaust gases of the downhole combustor, and one or more aerosol nozzles situated within the exhaust flue of the well casing for injecting an aerosol limestone dust into the exhaust gases of the combustor as the exhaust gases travel up the flue.

  11. Limit analysis of pipe clamps

    SciTech Connect

    Flanders, H.E. Jr.

    1990-01-01

    The Service Level D (faulted) load capacity of a conventional three-bolt pipe-clamp based upon the limit analysis method is presented. The load distribution, plastic hinge locations, and collapse load are developed for the lower bound limit load method. The results of the limit analysis are compared with the manufacturer's rated loads. 3 refs.

  12. Downhole seismic logging for high-resolution reflection surveying in unconsolidated overburden

    SciTech Connect

    Hunter, J.A.; Pullan, S.E.; Burns, R.A.; Good, R.L.; Harris, J.B.; Pugin, A.; Skvortsov, A.; Goriainov, N.N.

    1998-07-01

    Downhole seismic velocity logging techniques have been developed and applied in support of high-resolution reflection seismic surveys. Data obtained from downhole seismic logging can provide accurate velocity-depth functions and directly correlate seismic reflections to depth. The methodologies described in this paper are designed for slimhole applications in plastic-cased boreholes (minimum ID of 50 mm) and with source and detector arrays that yield similar frequency ranges and vertical depth resolutions as the surface reflection surveys. Compressional- (P-) wave logging uses a multichannel hydrophone array with 0.5-m detector spacings in a fluid-filled borehole and a high-frequency, in-hole shotgun source at the surface. Overlapping array positions downhole results in redundant first-arrival data which can be processed to provide accurate interval velocities. The data also can be displayed as a record suite, showing reflections and directly correlating reflection events with depths. Example applications include identification of gas zones, lithological boundaries within unconsolidated sediments, and the overburden-bedrock interface. Shear- (S-) wave logging uses a slimhole, well-locked, three-component (3-C) geophone pod and a horizontally polarized, hammer-and-loaded-plate source at ground surface. In unconsolidated sediments, shear-wave velocity contrasts can be associated with changes in material density or dynamic shear modulus, which in turn can be related to consolidation. Example applications include identification of a lithological boundary for earthquake hazard applications and mapping massive ice within permafrost materials.

  13. A clamped rectangular plate containing a crack

    NASA Technical Reports Server (NTRS)

    Tang, R.; Erdogan, F.

    1985-01-01

    The general problem of a rectangular plate clamped along two parallel sides and containing a crack parallel to the clamps is considered. The problem is formulated in terms of a system of singular integral equations and the asymptotic behavior of the stress state near the corners is investigated. Numerical examples are considered for a clamped plate without a crack and with a centrally located crack, and the stress intensity factors and the stresses along the clamps are calculated.

  14. Evaluation of alternatives in downhole steam generation

    SciTech Connect

    Not Available

    1981-09-01

    The objective is to evaluate two alternative approaches, taken by Sandia and World Energy Systems in their development of downhole steam generators, in terms of the requirements for commercialization and the technical and economic goals which each one must reach in order to satisfy those requirements. The conclusions are as follows: (1) The high-pressure downhole steam generator being developed by Sandia has potential for commercialization for production of heavy oil in the next few years. (2) The critical performance parameter is oil yield and can be expressed in terms of bbl oil/million Btu of steam generated; the yield which is required for clear economic attractiveness of the high-pressure generator is 1.2 bbl/10/sup 6/ Btu which corresponds to 5.3 bbl steam/bbl oil. (3) The downhole hydrogen/oxygen burner being developed by World Energy Systems has potential for commercialization for production of resources which are now unproducible or uneconomical. (4) The critical performance provided in nearly 1100 pre- and post-training forms returned by the solarr and 201 stream sediment samples. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the survey area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. Ground water data indicate that high uranium values occur almost exclusively in the western portion of the quadrangle along the eastern portion of the Williston Basin. These high uranium values occur primarily in Pleistocene delta deposits and in glacial outwash and till. Groundwater in this area is geographically associated with high values of calcium, magnesium, manganese, potassium, selenium, strontium, sulfate, and total alkalinity. Stream sediment data indicate high uranium value the relative concentration of Sm/sup 2 +/ and Sm/sup 3 +/ ions changes with the change of composition.

  15. Downhole seismic noise measurements in the Beowawe geothermal field, Nevada

    SciTech Connect

    Rutledge, J.T.; Albright, J.N.; Batra, R.

    1985-01-01

    A downhole seismic noise study was conducted at The Geysers area of Chevron's Beowawe geothermal field. Four wells were acoustically monitored with sensors placed simultaneously downhole and at the wellhead. Analyses included the correlation of downhole to surficial noise characteristics, well-to-well data correlations for noise source location or direction, and testing for the presence of borehole acoustic coupling between downhole and wellhead receivers. Intrawell cross-correlations in cased or lined boreholes clearly indicate acoustic coupling between wellhead and downhole receivers. Mean-integrated power values calculated over three frequency intervals indicate that the coupled signal is in the frequency interval 30 to 85 Hz and is the dominant component of signal downhole. Surficial variations of noise intensity in the frequency interval 0.5 to 15 Hz show little relation to simultaneously monitored downhole noise integrity. Downhole noise measurement appears to be predominantly a function of near-borehole phenomena in lined or cased holes. Measurements in an uncased borehole showed good correlations with surficial variations. Interwell correlations of noise could not be found. Reservoir noise in the Beowawe field indicated by conventional geophysical surveys could not be corroborated. 8 refs., 4 figs.

  16. Sullair low pressure downhole steam generator system

    SciTech Connect

    Klingler, R.P.

    1982-01-01

    Scientists and engineers are continually searching for techniques to release more oil from known reservoirs to improve productivity and lessen dependence on new finds. Based on a record of success dating to the early 1960s, thermal methods, and in particular methodology for steam treating deep reservoirs, have become an area of intense activity. In the U.S. alone, it has been reported that ca 300,000 bopd was produced in 1981 by traditional surface steam methods. Of the thermal techniques emerging, downhole steam generation is of particular interest in this discussion. 11 references.

  17. Downhole delay assembly for blasting with series delay

    DOEpatents

    Ricketts, Thomas E.

    1982-01-01

    A downhole delay assembly is provided which can be placed into a blasthole for initiation of explosive in the blasthole. The downhole delay assembly includes at least two detonating time delay devices in series in order to effect a time delay of longer than about 200 milliseconds in a round of explosions. The downhole delay assembly provides a protective housing to prevent detonation of explosive in the blasthole in response to the detonation of the first detonating time delay device. There is further provided a connection between the first and second time delay devices. The connection is responsive to the detonation of the first detonating time delay device and initiates the second detonating time delay device. A plurality of such downhole delay assemblies are placed downhole in unfragmented formation and are initiated simultaneously for providing a round of explosive expansions. The explosive expansions can be used to form an in situ oil shale retort containing a fragmented permeable mass of formation particles.

  18. Method for bonding a transmission line to a downhole tool

    DOEpatents

    Hall, David R.; Fox, Joe

    2007-11-06

    An apparatus for bonding a transmission line to the central bore of a downhole tool includes a pre-formed interface for bonding a transmission line to the inside diameter of a downhole tool. The pre-formed interface includes a first surface that substantially conforms to the outside contour of a transmission line and a second surface that substantially conforms to the inside diameter of a downhole tool. In another aspect of the invention, a method for bonding a transmission line to the inside diameter of a downhole tool includes positioning a transmission line near the inside wall of a downhole tool and placing a mold near the transmission line and the inside wall. The method further includes injecting a bonding material into the mold and curing the bonding material such that the bonding material bonds the transmission line to the inside wall.

  19. Apparatus for responding to an anomalous change in downhole pressure

    DOEpatents

    Hall, David R.; Fox, Joe; Wilde, Tyson; Barlow, Jonathan S.

    2010-04-13

    A method of responding to an anomalous change in downhole pressure in a bore hole comprises detecting the anomalous change in downhole pressure, sending a signal along the segmented electromagnetic transmission path, receiving the signal, and performing a automated response. The anomalous change in downhole pressure is detected at a first location along a segmented electromagnetic transmission path, and the segmented electromagnetic transmission path is integrated into the tool string. The signal is received by at least one receiver in communication with the segmented electromagnetic transmission path. The automated response is performed along the tool string. Disclosed is an apparatus for responding to an anomalous change in downhole pressure in a downhole tool string, comprising a segmented electromagnetic transmission path connecting one or more receivers and at least one pressure sensor.

  20. Down-hole periodic seismic generator

    DOEpatents

    Hardee, H.C.; Hills, R.G.; Striker, R.P.

    1982-10-28

    A down hole periodic seismic generator system is disclosed for transmitting variable frequency, predominantly shear-wave vibration into earth strata surrounding a borehole. The system comprises a unitary housing operably connected to a well head by support and electrical cabling and contains clamping apparatus for selectively clamping the housing to the walls of the borehole. The system further comprises a variable speed pneumatic oscillator and a self-contained pneumatic reservoir for producing a frequency-swept seismic output over a discrete frequency range.

  1. INTEGRATED POLARIZATION PROPERTIES OF 3C48, 3C138, 3C147, AND 3C286

    SciTech Connect

    Perley, R. A.; Butler, B. J. E-mail: BButler@nrao.edu

    2013-06-01

    We present the integrated polarization properties of the four compact radio sources 3C48, 3C138, 3C147, and 3C286, from 1 to 50 GHz, over a 30 yr time frame spanning 1982-2012. Using the polarized emission of Mars, we have determined that the position angle of the linearly polarized emission of 3C286 rises from 33 Degree-Sign at 8 GHz to 36 Degree-Sign at 45 GHz. There is no evidence for a change in the position angle over time. Using these values, the position angles of the integrated polarized emission from the other three sources are determined as a function of frequency and time. The fractional polarization of 3C286 is found to be slowly rising, at all frequencies, at a rate of {approx}0.015% yr{sup -1}. The fractional polarizations of 3C48, 3C138, and 3C147 are all slowly variable, with the variations correlated with changes in the total flux densities of these sources.

  2. Solution structure of an "open" E. coli Pol III clamp loader sliding clamp complex.

    PubMed

    Tondnevis, Farzaneh; Weiss, Thomas M; Matsui, Tsutomu; Bloom, Linda B; McKenna, Robert

    2016-06-01

    Sliding clamps are opened and loaded onto primer template junctions by clamp loaders, and once loaded on DNA, confer processivity to replicative polymerases. Previously determined crystal structures of eukaryotic and T4 clamp loader-clamp complexes have captured the sliding clamps in either closed or only partially open interface conformations. In these solution structure studies, we have captured for the first time the clamp loader-sliding clamp complex from Escherichia coli using size exclusion chromatography coupled to small angle X-ray scattering (SEC-SAXS). The data suggests the sliding clamp is in an open conformation which is wide enough to permit duplex DNA binding. The data also provides information about spatial arrangement of the sliding clamp with respect to the clamp loader subunits and is compared to complex crystal structures determined from other organisms. PMID:26968362

  3. Data transmission system for a downhole component

    DOEpatents

    Hall, David R.; Hall, Jr., Tracy H.; Pixton, David S.; Dahlgren, Scott Steven; Fox, Joe; Sneddon, Cameron; Briscoe, Michael A.

    2006-05-09

    The invention is a system for transmitting data through a string of downhole components. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string. Each component has a first and second end, with a first communication element located at the first end and a second communication element located at the second end. Each communication element includes a first contact and a second contact. The system also includes a coaxial cable running between the first and second communication elements, the coaxial cable having a conductive tube and a conductive core within it. The system also includes a first and second connector for connecting the first and second communication elements respectively to the coaxial cable. Each connector includes a conductive sleeve, lying concentrically within the conductive tube, which fits around and makes electrical contact with the conductive core. The conductive sleeve is electrically isolated from the conductive tube. The conductive sleeve of the first connector is in electrical contact with the first contact of the first communication element, the conductive sleeve of the second connector is in electrical contact with the first contact of the second communication element, and the conductive tube is in electrical contact with both the second contact of the first communication element and the second contact of the second communication element.

  4. Data Transmission System For A Downhole Component

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Fox, Joe; Briscoe, Michael

    2005-01-18

    The invention is a system for transmitting data through a string of downhole components. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string. Each component has a first and second end, with a first communication element located at the first end and a second communication element located at the second end. Each communication element includes a first contact and a second contact. The system also includes a coaxial cable running between the first and second communication elements, the coaxial cable having a conductive tube and a conductive core within it. The system also includes a first and second connector for connecting the first and second communication elements respectively to the coaxial cable. Each connector includes a conductive sleeve, lying concentrically within the conductive tube, which fits around and makes electrical contact with the conductive core. The conductive sleeve is electrically isolated from the conductive tube. The conductive sleeve of the first connector is in electrical contact with the first contact of the first communication element, the conductive sleeve of the second connector is in electrical contact with the first contact of the second communication element, and the conductive tube is in electrical contact with both the second contact of the first communication element and the second contact of the second communication element.

  5. Dynamics of Open DNA Sliding Clamps.

    PubMed

    Oakley, Aaron J

    2016-01-01

    A range of enzymes in DNA replication and repair bind to DNA-clamps: torus-shaped proteins that encircle double-stranded DNA and act as mobile tethers. Clamps from viruses (such as gp45 from the T4 bacteriophage) and eukaryotes (PCNAs) are homotrimers, each protomer containing two repeats of the DNA-clamp motif, while bacterial clamps (pol III β) are homodimers, each protomer containing three DNA-clamp motifs. Clamps need to be flexible enough to allow opening and loading onto primed DNA by clamp loader complexes. Equilibrium and steered molecular dynamics simulations have been used to study DNA-clamp conformation in open and closed forms. The E. coli and PCNA clamps appear to prefer closed, planar conformations. Remarkably, gp45 appears to prefer an open right-handed spiral conformation in solution, in agreement with previously reported biophysical data. The structural preferences of DNA clamps in solution have implications for understanding the duty cycle of clamp-loaders. PMID:27148748

  6. Dynamics of Open DNA Sliding Clamps

    PubMed Central

    Oakley, Aaron J.

    2016-01-01

    A range of enzymes in DNA replication and repair bind to DNA-clamps: torus-shaped proteins that encircle double-stranded DNA and act as mobile tethers. Clamps from viruses (such as gp45 from the T4 bacteriophage) and eukaryotes (PCNAs) are homotrimers, each protomer containing two repeats of the DNA-clamp motif, while bacterial clamps (pol III β) are homodimers, each protomer containing three DNA-clamp motifs. Clamps need to be flexible enough to allow opening and loading onto primed DNA by clamp loader complexes. Equilibrium and steered molecular dynamics simulations have been used to study DNA-clamp conformation in open and closed forms. The E. coli and PCNA clamps appear to prefer closed, planar conformations. Remarkably, gp45 appears to prefer an open right-handed spiral conformation in solution, in agreement with previously reported biophysical data. The structural preferences of DNA clamps in solution have implications for understanding the duty cycle of clamp-loaders. PMID:27148748

  7. Deep Downhole Seismic Testing for Earthquake Engineering Studies

    SciTech Connect

    Stokoe, Kenneth H.; Li, Song Cheng; Cox, Brady R.; Menq, Farn-Yuh; Rohay, Alan C.

    2008-10-17

    Downhole seismic testing is one field test that is commonly used to determine compression-wave (P) and shear-wave (S) velocity profiles in geotechnical earthquake engineering investigations. These profiles are required input in evaluations of the responses to earthquake shaking of geotechnical sites and structures at these sites. In the past, traditional downhole testing has generally involved profiling in the 30- to 150-m depth range. As the number of field seismic investigations at locations with critical facilities has increased, profiling depths have also increased. An improved downhole test that can be used for wave velocity profiling to depths of 300 to 600 m or more is presented.

  8. High-speed pressure clamp.

    PubMed

    Besch, Stephen R; Suchyna, Thomas; Sachs, Frederick

    2002-10-01

    We built a high-speed, pneumatic pressure clamp to stimulate patch-clamped membranes mechanically. The key control element is a newly designed differential valve that uses a single, nickel-plated piezoelectric bending element to control both pressure and vacuum. To minimize response time, the valve body was designed with minimum dead volume. The result is improved response time and stability with a threefold decrease in actuation latency. Tight valve clearances minimize the steady-state air flow, permitting us to use small resonant-piston pumps to supply pressure and vacuum. To protect the valve from water contamination in the event of a broken pipette, an optical sensor detects water entering the valve and increases pressure rapidly to clear the system. The open-loop time constant for pressure is 2.5 ms for a 100-mmHg step, and the closed-loop settling time is 500-600 micros. Valve actuation latency is 120 micros. The system performance is illustrated for mechanically induced changes in patch capacitance. PMID:12397401

  9. Progressive cavity pump for downhole inflatable packer

    SciTech Connect

    Clark, J.A.

    1992-03-24

    This patent describes a downhole inflatable packer pump. It comprises: case means for attaching to a lower testing string portion and having an inlet and an outlet, the outlet being communicable with an inflatable packer at a location below the pump; mandrel means, rotatably disposed within the case means, for connecting to an upper testing string portion for mutual rotation therewith and rotating within the case means; an elastomeric pump stator disposed in the case means, the stator having a convoluted inner surface; a rotor extending form the mandrel means and into the stator, the rotor having a convoluted outer surface, the stator and rotor defining a plurality of cavities therebetween, whereby rotation of the rotor within the stator moves fluid progressively from cavity to cavity and thereby from the inlet to the outlet; passageway means for providing fluid communication between the lower testing string portion and the upper testing string portion, the passageway means being sealing separated from the cavities.

  10. Downhole steam generator subject of Sandia tests

    SciTech Connect

    Not Available

    1981-05-01

    The first field test of a down-hole steam generator developed to inject hot steam directly into deeply buried heavy oil reservoirs began in mid-April near Long Beach, CA. The 23-ft-long, 6-in.-diameter generator, developed by Sandia National Laboratories, will produce up to 800 cu ft of 500 F steam a minute (1.2 MW thermal) at the bottom of a 2500-ft well. Goals of the test are to demonstrate the feasibility of operating the generator at realistic depths and to determine its overall performance and environmental impact. Development of the generator is part of the US Department of Energy's Project Deep Steam to identify techniques for recovering heavy oil from deeply buried (greater than 2500 ft) reservoirs.

  11. Releasable latch for downhole well tools

    SciTech Connect

    Setterberg, J.R. Jr.

    1986-02-18

    This patent describes a latch for releasably anchoring well tools at a preselected downhole location defined in part by an annular recess. The latch consists of: a. a mandrel; b. a device for locking the mandrel with the recess; c. the locking means slidably mounted on the mandrel; d. a backup device having a first position which allows disengagement of the locking device from the recess and a second position which holds the locking device against disengagement from the recess; e. a first frangible device holding the backup device in its first position and releasing the backup device in response to application of a predetermined force tending to move the backup device to its second position; and f. a second frangible device for holding the backup device in its second position.

  12. Multipurpose Acoustic Sensor for Downhole Fluid Monitoring

    SciTech Connect

    Pantea, Cristian

    2012-05-04

    The projects objectives and purpose are to: (1) development a multipurpose acoustic sensor for downhole fluid monitoring in Enhanced Geothermal Systems (EGS) reservoirs over typical ranges of pressures and temperatures and demonstrate its capabilities and performance for different EGS systems; (2) determine in real-time and in a single sensor package several parameters - temperature, pressure, fluid flow and fluid properties; (3) needed in nearly every phase of an EGS project, including Testing of Injection and Production Wells, Reservoir Validation, Inter-well Connectivity, Reservoir Scale Up and Reservoir Sustainability. (4) Current sensors are limited to operating at lower temperatures, but the need is for logging at high temperatures. The present project deals with the development of a novel acoustic-based sensor that can work at temperatures up to 374 C, in inhospitable environments.

  13. Signal connection for a downhole tool string

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Bradford, Kline; Fox, Joe; Briscoe, Michael

    2006-08-29

    A signal transmission connection for a tool string used in exploration and production of natural resources, namely: oil, gas, and geothermal energy resources. The connection comprises first and second annular elements deployed in cooperative association with each other. The respective elements comprise inductive transducers that are capable of two-way signal transmission between each other, with downhole components of the tool string, and with ground-level equipment. The respective inductive transducers comprise one or more conductive loops housed within ferrite troughs, or within ferrite trough segments. When energized, the conductive loops produce a magnetic field suitable for transmitting the signal. The second element may be rotational in drilling applications. The respective elements may be fitted with electronic equipment to aid and manipulate the transmission of the signal. The first element may also be in communication with the World Wide Web.

  14. Advanced motor driven clamped borehole seismic receiver

    DOEpatents

    Engler, Bruce P.; Sleefe, Gerard E.; Striker, Richard P.

    1993-01-01

    A borehole seismic tool including a borehole clamp which only moves perpendicular to the borehole. The clamp is driven by an electric motor, via a right angle drive. When used as a seismic receiver, the tool has a three part housing, two of which are hermetically sealed. Accelerometers or geophones are mounted in one hermetically sealed part, the electric meter in the other hermetically sealed part, and the clamp and right angle drive in the third part. Preferably the tool includes cable connectors at both ends. Optionally a shear plate can be added to the clamp to extend the range of the tool.

  15. Advanced motor driven clamped borehole seismic receiver

    DOEpatents

    Engler, B.P.; Sleefe, G.E.; Striker, R.P.

    1993-02-23

    A borehole seismic tool is described including a borehole clamp which only moves perpendicular to the borehole. The clamp is driven by an electric motor, via a right angle drive. When used as a seismic receiver, the tool has a three part housing, two of which are hermetically sealed. Accelerometers or geophones are mounted in one hermetically sealed part, the electric motor in the other hermetically sealed part, and the clamp and right angle drive in the third part. Preferably the tool includes cable connectors at both ends. Optionally a shear plate can be added to the clamp to extend the range of the tool.

  16. DOWNHOLE POWER GENERATION AND WIRELESS COMMUNICATIONS FOR INTELLIGENT COMPLETIONS APPLICATIONS

    SciTech Connect

    Paul Tubel

    2004-02-01

    The development work during this quarter was focused in the assembly of the downhole power generator hardware and its electronics module. The quarter was also spent in the development of the surface system electronics and software to extract the acoustic data transmitted from downhole to the surface from the noise generated by hydrocarbon flow in wells and to amplify very small acoustic signals to increase the distance between the downhole tool and the surface receiver. The tasks accomplished during this report period were: (1) Assembly of the downhole power generator mandrel for generation of electrical power due to flow in the wellbore. (2) Test the piezoelectric wafers to assure that they are performing properly prior to integrating them to the mechanical power generator mandrel. (3) Coat the power generator wafers to prevent water from shorting the power generator wafers. (4) Test of the power generator using a water tower and an electric pump to create a water flow loop. (5) Test the power harvesting electronics module. (6) Upgrade the signal condition and amplification from downhole into the surface system. (7) Upgrade the surface processing system capability to process data faster. (8) Create a new filtering technique to extract the signal from noise after the data from downhole is received at the surface system.

  17. Diverless pipeline repair clamp: Phase 2

    SciTech Connect

    Miller, J.E.; Lane, B. )

    1992-04-01

    The objective of this project sponsored by the Pipeline Research Committee of the American Gas Association, is to develop a system suitable for repairing small leaks on deepwater pipelines. Phase I of the project, completed in 1990 by Stress Engineering Services, Inc. investigated the types of problems that would have to be overcome to effect a diverless clamp-type repair. Several repair systems were investigated and ten mechanisms were proposed that could be used to secure two clamp halves together. This current Phase 11 effort, is to take two most promising clamp concepts from Phase 1, further evaluate hardware and installation issues, develop conceptual designs, and determine which concept should be carried forward to detailed design. The two concepts evaluated were (1) a bolted split-sleeve clamp suited for ROV installation, and (2) a hydraulically self-actuating clamp requiring only placement on the pipe and actuation by ROV hydraulic hot stabs. Both concepts were evaluated for a 12-inch (324 mm) nominal pipe diameter with an ANSI 900 (15.3 mPa) pressure rating, presuming either system could be adapted to a wider range of pipe sizes and design pressures. Based on the results of this investigation a modified bolted split-sleeve clamp was recommended over the hydraulically self-actuating clamp. The main reasons are (1) the bolted split-sleeve clamp can be adapted to installation by a ROV, (2) sealing and clamping mechanisms borrow from available proven technology, (3) it would require less development effort than the hydraulically self-actuating clamp, and (4) the bolted split-sleeve clamp would probably result in a simpler, less costly design.

  18. Protein folding in a force clamp

    NASA Astrophysics Data System (ADS)

    Cieplak, Marek; Szymczak, P.

    2006-05-01

    Kinetics of folding of a protein held in a force clamp are compared to an unconstrained folding. The comparison is made within a simple topology-based dynamical model of ubiquitin. We demonstrate that the experimentally observed variations in the end-to-end distance reflect microscopic events during folding. However, the folding scenarios in and out of the force clamp are distinct.

  19. Completion system for downhole steam generator

    SciTech Connect

    Vandevier, J.E.

    1989-05-30

    This patent describes an apparatus for providing electrical power to a downhole steam generator in a cased well. The method consists of: a packer supported on a string of tubing, the packer having means for sealing against casing in the well and at least one conduit extending longitudinally through the packer; a connector box mounted below the lower end of the packer, the connector box having a connector plate containing a plurality of passages; a plurality of feed through electrical connectors mounted in insulators in the passages in the connector plate; support means for mounting the steam generator below the connector box; an aperture located in the sidewall of the tubing immediately above the packer; an electrical cable extending from the surface alongside the tubing into the aperture and through the conduit into the connector box, the electrical cable having a plurality of electrical conductors, each of which ends in a terminal that is electrically connected to one of the electrical connectors; and electrical conductors extending between the steam generator and engaging a lower end of each electrical connector in the connection plate.

  20. Continuous chain bit with downhole cycling capability

    DOEpatents

    Ritter, Don F.; St. Clair, Jack A.; Togami, Henry K.

    1983-01-01

    A continuous chain bit for hard rock drilling is capable of downhole cycling. A drill head assembly moves axially relative to a support body while the chain on the head assembly is held in position so that the bodily movement of the chain cycles the chain to present new composite links for drilling. A pair of spring fingers on opposite sides of the chain hold the chain against movement. The chain is held in tension by a spring-biased tensioning bar. A head at the working end of the chain supports the working links. The chain is centered by a reversing pawl and piston actuated by the pressure of the drilling mud. Detent pins lock the head assembly with respect to the support body and are also operated by the drilling mud pressure. A restricted nozzle with a divergent outlet sprays drilling mud into the cavity to remove debris. Indication of the centered position of the chain is provided by noting a low pressure reading indicating proper alignment of drilling mud slots on the links with the corresponding feed branches.

  1. Downhole pump with retrievable nozzle assembly

    SciTech Connect

    Roeder, G.K.

    1991-10-08

    This paper describes improvement in a system for producing fluid from a wellbore wherein a downhole jet pump has a main body with there being a passageway extending therethrough and the passageway having an upper end opposed to a lower end; there being power fluid inlet means at the upper end of the passageway for connecting the pump to a source of power fluid, formation fluid inlet means at the lower end of the passageway for connecting the pump to a source of formation fluid; and a produced fluid outlet through which spent power fluid admixed with formation fluid can flow. The improvement comprises: the pump includes a nozzle and a throat affixed together in spaced relationship respective to one another and forming a unitary assembly for producing formation fluid in response to power fluid flowing therethrough; a seating cavity formed between the upper end and the lower end of the passageway; the seating cavity is axially aligned with the upper end of the passageway; the seating cavity having an upper cylindrical part spaced from a lower cylindrical part with there being a formation fluid working chamber formed therebetween and connected to the formation fluid inlet.

  2. Sound speed in downhole flow measurement.

    PubMed

    Ünalmis, Ö Haldun

    2016-07-01

    This paper describes the use of sound speed in flow measurement applications in the high-pressure/high-temperature downhole environment. The propagation speed of a sound wave is a powerful tool to extract useful information from a flowing fluid medium in pipe whether the medium consists of a single-phase or multiphase flow. Considering the complex nature of the flow patterns and changing phase fractions from reservoir to surface, utilizing the propagation speed of sound of a fluid mixture is not a trivial task, especially if the interest is real-time flow measurement. The demanding applications span a wide spectrum from noisy medium originating from fast-moving gas/liquid flows to quiet medium originating from slow-moving liquid/liquid flows. In the current work, multiple flow loop tests are conducted in different facilities to evaluate the direct use of sound speed in flow rate measurement and the results are associated with real-life field examples. A tool analysis map is developed that addresses the use of sound speed for flow measurement under different scenarios. Although most examples are based on strain-based local sensing of the flow, the use of sound speed is independent of the methodology and can be implemented by other methods such as acoustic-based distributed sensing. PMID:27475167

  3. The Monogenean Which Lost Its Clamps

    PubMed Central

    Justine, Jean-Lou; Rahmouni, Chahrazed; Gey, Delphine; Schoelinck, Charlotte; Hoberg, Eric P.

    2013-01-01

    Ectoparasites face a daily challenge: to remain attached to their hosts. Polyopisthocotylean monogeneans usually attach to the surface of fish gills using highly specialized structures, the sclerotized clamps. In the original description of the protomicrocotylid species Lethacotyle fijiensis, described 60 years ago, the clamps were considered to be absent but few specimens were available and this observation was later questioned. In addition, genera within the family Protomicrocotylidae have either clamps of the “gastrocotylid” or the “microcotylid” types; this puzzled systematists because these clamp types are characteristic of distinct, major groups. Discovery of another, new, species of the genus Lethacotyle, has allowed us to explore the nature of the attachment structures in protomicrocotylids. Lethacotyle vera n. sp. is described from the gills of the carangid Caranx papuensis off New Caledonia. It is distinguished from Lethacotyle fijiensis, the only other species of the genus, by the length of the male copulatory spines. Sequences of 28S rDNA were used to build a tree, in which Lethacotyle vera grouped with other protomicrocotylids. The identity of the host fish was confirmed with COI barcodes. We observed that protomicrocotylids have specialized structures associated with their attachment organ, such as lateral flaps and transverse striations, which are not known in other monogeneans. We thus hypothesized that the clamps in protomicrocotylids were sequentially lost during evolution, coinciding with the development of other attachment structures. To test the hypothesis, we calculated the surfaces of clamps and body in 120 species of gastrocotylinean monogeneans, based on published descriptions. The ratio of clamp surface: body surface was the lowest in protomicrocotylids. We conclude that clamps in protomicrocotylids are vestigial organs, and that occurrence of “gastrocotylid” and simpler “microcotylid” clamps within the same family are

  4. 33 CFR 183.560 - Hose clamps: Installation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Hose clamps: Installation. Each hose clamp on a hose from the fuel tank to the fuel inlet connection on..., pipe, or hose fitting; and (d) Not depend solely on the spring tension of the clamp for...

  5. Surface characterization of selected LDEF tray clamps

    NASA Technical Reports Server (NTRS)

    Cromer, T. F.; Grammer, H. L.; Wightman, J. P.; Young, Philip R.; Slemp, Wayne S.

    1993-01-01

    The surface characterization of chromic acid anodized 6061-T6 aluminum alloy tray clamps has shown differences in surface chemistry depending upon the position on the Long Duration Exposure Facility (LDEF). Water contact angle results showed no changes in wettability of the tray clamps. The overall surface topography of the control, trailing edge(E3) and leading edge(D9) samples was similar. The thickness of the aluminum oxide layer for all samples determined by Auger depth profiling was less than one micron. X-ray photoelectron spectroscopy (XPS) analysis of the tray clamps showed significant differences in the surface composition. Carbon and silicon containing compounds were the primary contaminants detected.

  6. Dual Functions, Clamp Opening and Primer-Template Recognition, Define a Key Clamp Loader Subunit

    PubMed Central

    Coman, Maria Magdalena; Jin, Mi; Ceapa, Razvan; Finkelstein, Jeff; O'Donnell, Michael; Chait, Brian T.; Hingorani, Manju M.

    2010-01-01

    Clamp loader proteins catalyze assembly of circular sliding clamps on DNA to enable processive DNA replication. During the reaction, the clamp loader binds primer-template DNA and positions it in the center of a clamp to form a topological link between the two. Clamp loaders are multi-protein complexes, such as the five protein Escherichia coli, Saccharomyces cerevisiae, and human clamp loaders, and the two protein Pyrococcus furiosus and Methanobacterium thermoautotrophicum clamp loaders, and thus far the site(s) responsible for binding and selecting primer-template DNA as the target for clamp assembly remain unknown. To address this issue, we analyzed the interaction between the E. coli γ complex clamp loader and DNA using UV-induced protein–DNA cross-linking and mass spectrometry. The results show that the δ subunit in the γ complex makes close contact with the primer-template junction. Tryptophan 279 in the δ C-terminal domain lies near the 3′-OH primer end and may play a key role in primer-template recognition. Previous studies have shown that δ also binds and opens the β clamp (hydrophobic residues in the N-terminal domain of δ contact β. The clamp-binding and DNA-binding sites on δ appear positioned for facile entry of primer-template into the center of the clamp and exit of the template strand from the complex. A similar analysis of the S. cerevisiae RFC complex suggests that the dual functionality observed for δ in the γ complex may be true also for clamp loaders from other organisms. PMID:15364574

  7. Downhole Vibration Monitoring and Control System

    SciTech Connect

    Martin E. Cobern

    2007-09-30

    The objective of this program is to develop a system to both monitor the vibration of a bottomhole assembly, and to adjust the properties of an active damper in response to these measured vibrations. The key feature of this system is its use of a magnetorheological fluid (MRF) to allow the damping coefficient to be changed extensively, rapidly and reversibly without the use of mechanical valves, but only by the application of a current. Phase I of this program, which entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype, was completed on May 31, 2004. Much of the effort was devoted to the design and testing of the MRF damper, itself. The principal objectives of Phase II were: more extensive laboratory testing, including the evaluation of different feedback algorithms for control of the damper; design and manufacture of a field prototype system; and, testing of the field prototype in a drilling laboratory. Phase II concluded on January 31, 2006, and a final report was issued. Work on Phase III of the project began during the first quarter, 2006, with the objectives of building precommercial prototypes, testing them in a drilling laboratory and the field; developing and implementing a commercialization plan. All of these have been accomplished. The Downhole Vibration Monitoring & Control System (DVMCS) prototypes have been successfully proven in testing at the TerraTek drilling facility and at the Rocky Mountain Oilfield Test Center (RMOTC.) Based on the results of these tests, we have signed a definitive development and distribution agreement with Smith, and commercial deployment is underway. This current version of the DVMCS monitors and controls axial vibrations. Due to time and budget constraints of this program, it was not possible to complete a system that would also deal with lateral and torsional (stick-slip) vibrations as originally planned; however, this effort is continuing without DOE

  8. Software defined down-hole telemetric systems: training course

    NASA Astrophysics Data System (ADS)

    Morozov, Oleg G.; Danilaev, Dmitry P.; Denisenko, Pavel E.; Dautova, Rezeda V.; Nureev, Ilnur I.; Sakhabutdinov, Airat Z.; Feofilaktov, Sergey V.

    2015-03-01

    The paper is devoted for presentation of training course for applications and construction principles of poly-harmonic (two-frequency or four-frequency) cw laser systems for characterization of different nonlinear scattering effects in fibers and reflection of devices based on fiber Bragg gratings (FBG) in down-hole telemetric sensor nets, which are widely used in down-hole telemetric systems. In particular, we'll speak about evaluation of Mandelstam-Brillouin gain contour, Raman scattering contours and FBG reflection spectra characterization. Investigation methods and approaches are based on the unity of resonant structures of generated fiber responses on exciting and probing radiation or external physical fields for all given effects. The main decision is based on poly-harmonic probing of formed resonance responses. Training course united idea is software defined approach for down-hole parameters characterization in spite of measuring conversion principles.

  9. Dynamic clamp with StdpC software

    PubMed Central

    2011-01-01

    Dynamic clamp is a powerful method that allows the introduction of artificial electrical components into target cells to simulate ionic conductances and synaptic inputs. This method is based on a fast cycle of measuring the membrane potential of a cell, calculating the current of a desired simulated component using an appropriate model and injecting this current into the cell. Here, we present a dynamic clamp protocol using free, fully integrated, open-source software (StdpC, Spike timing dependent plasticity Clamp). Use of this protocol does not require specialist hardware, costly commercial software, experience in real time operating systems or a strong programming background. The software enables the configuration and operation of a wide range of complex and fully automated dynamic clamp experiments via an intuitive and powerful interface with a minimal initial lead-time of a few hours. After initial configuration, experimental results can be generated within minutes of cell impalement. PMID:21372819

  10. Molecular Mechanisms of DNA Polymerase Clamp Loaders

    NASA Astrophysics Data System (ADS)

    Kelch, Brian; Makino, Debora; Simonetta, Kyle; O'Donnell, Mike; Kuriyan, John

    Clamp loaders are ATP-driven multiprotein machines that couple ATP hydrolysis to the opening and closing of a circular protein ring around DNA. This ring-shaped clamp slides along DNA, and interacts with numerous proteins involved in DNA replication, DNA repair and cell cycle control. Recently determined structures of clamp loader complexes from prokaryotic and eukaryotic DNA polymerases have revealed exciting new details of how these complex AAA+ machines perform this essential clamp loading function. This review serves as background to John Kuriyan's lecture at the 2010 Erice School, and is not meant as a comprehensive review of the contributions of the many scientists who have advanced this field. These lecture notes are derived from recent reviews and research papers from our groups.

  11. Patch-Clamp Fluorometry: Electrophysiology meets Fluorescence

    PubMed Central

    Kusch, Jana; Zifarelli, Giovanni

    2014-01-01

    Ion channels and transporters are membrane proteins whose functions are driven by conformational changes. Classical biophysical techniques provide insight into either the structure or the function of these proteins, but a full understanding of their behavior requires a correlation of both these aspects in time. Patch-clamp and voltage-clamp fluorometry combine spectroscopic and electrophysiological techniques to simultaneously detect conformational changes and ionic currents across the membrane. Since its introduction, patch-clamp fluorometry has been responsible for invaluable advances in our knowledge of ion channel biophysics. Over the years, the technique has been applied to many different ion channel families to address several biophysical questions with a variety of spectroscopic approaches and electrophysiological configurations. This review illustrates the strength and the flexibility of patch-clamp fluorometry, demonstrating its potential as a tool for future research. PMID:24655500

  12. Structural analysis of a eukaryotic sliding DNA clamp-clamp loadercomplex.

    SciTech Connect

    Bowman, Gregory D.; O'Donnell, Mike; Kuriyan, John

    2006-06-17

    Sliding clamps are ring-shaped proteins that encircle DNA and confer high processivity on DNA polymerases. Here we report the crystal structure of the five-protein clamp loader complex (replication factor-C, RFC) of the yeast Saccharomyces cerevisiae, bound to the sliding clamp (proliferating cell nuclear antigen, PCNA). Tight interfacial coordination of the ATP analogue ATP-?-S by RFC results in a spiral arrangement of the ATPase domains of the clamp loader above the PCNA ring. Placement of a model for primed DNA within the central hole of PCNA reveals a striking correspondence between the RFC spiral and the grooves of the DNA double helix. This model, in which the clamp loader complex locks onto primed DNA in a screw-cap-like arrangement, provides a simple explanation for the process by which the engagement of primer-template junctions by the RFC:PCNA complex results in ATP hydrolysis and release of the sliding clamp on DNA.

  13. Protein folding in a force-clamp

    NASA Astrophysics Data System (ADS)

    Cieplak, Marek; Szymczak, Piotr

    2006-03-01

    Kinetics of folding of a protein held in a force-clamp are compared to an unconstrained folding. The comparison is made within a simple topology-based dynamical model of ubiquitin. We demonstrate that the experimentally observed rapid changes in the end-to-end distance mirror microscopic events during folding. However, the folding scenarios in and out of the force-clamp are distinct.

  14. RUBBER BEARINGS FOR DOWN-HOLE PUMPS

    SciTech Connect

    Bob Sullivan Mammoth Pacific, L.P.

    2005-09-07

    Synopsis of project activity: 1998--Awarded cost share grant from DOE. 1st Qtr 1999--Developed fail safe lubricating system. 2nd Qtr 1999--Performed first large scale test with nitrile based bearings. It failed due to material swelling. Failure was blamed on improper tolerance. 3rd Qtr 1999--Material tests were performed with autoclaves and exposure tests to Casa Diablo fluids. Testing of Viton materials began. Alternate bearing designs were developed to limit risk of improper tolerances. 4th Qtr 1999--Site testing indicated a chemical attack on the bearing material caused the test failure and not improper bearing tolerance. 1st Qtr 2000--The assistance of Brookhaven National Laboratory was obtained in evaluating the chemical attack. The National Laboratory also began more elaborate laboratory testing on bearing materials. 2nd Qtr 2000--Testing indicated Viton was an inappropriate material due to degradation in Casa Diablo fluid. Testing of EPDM began. 3rd Qtr 2001--EPDM bearings were installed for another large scale test. Bearings failed again due to swelling. Further testing indicated that larger then expected oil concentrations existed in lubricating water geothermal fluid causing bearing failure. 2002-2003--Searched for and tested several materials that would survive in hot salt and oil solutions. Kalrez{reg_sign}, Viton{reg_sign}ETP 500 and Viton{reg_sign}GF were identified as possible candidates. 2003-2005--Kalrez{reg_sign}has shown superior resistance to downhole conditions at Casa Diablo from among the various materials tested. Viton ETP-500 indicated a life expectancy of 13 years and because it is significantly less expensive then Kalrez{reg_sign}, it was selected as the bearing material for future testing. Unfortunately during the laboratory testing period Dupont Chemical chose to stop manufacturing this specific formulation and replaced it with Viton ETP 600S. The material is available with six different fillers; three based on zinc oxide and three

  15. Diverless pipeline repair clamp, Phase 3

    SciTech Connect

    Miller, J.E.

    1993-08-01

    The objective of this project is to develop a system suitable for repairing small leaks in deep water pipelines. It is assumed that leak repair operations at the water depths in question will be performed by Remotely Operated Vehicles (ROV`s). This report summarizes the results of the third and final phase of this project. Phase 3 work included design, manufacture, and dry testing of (1) a one-half scale model of a 12 inch repair clamp, (2) a full-scale bolt test fixture to demonstrate bolt containment and startup under realistic misalignment of the clamp halves, and (3) a full-scale one-way cylinder for end seal activation. Phase 3 also included a study commissioned from Oceaneering directed at defining the interfaces of the clamp package and the ROV, including suggested procedures for deployment and positioning of the clamp package on the pipeline. Issues regarding bolt make-up by the ROV were also studied in detail and limitations in bolting capability were outlined. The conclusion of this work is that the clamping system described herein may be implemented in a direct manner. The design issues causing the most concern have been resolved through laboratory tests. Note however that all testing performed was mechanical in nature and performed in a dry environment. The recommended next development step, prior to declaring the system operational, is to manufacture a fully outfitted clamp package and to perform installation tests in a controlled underwater environment using a typical deepwater ROV. Wet tests are required in order to demonstrate ROV interfaces and installation procedures, however, the major mechanical features represented by the clamp design as well as its operation have been proven.

  16. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  17. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  18. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  19. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  20. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  1. Fallon FORGE GIS and Downhole Well Lithology Data

    SciTech Connect

    Doug Blankenship

    2015-12-23

    ArcGIS Map Package with MT Station Locations, 2D Seismic Lines, Well data, Known Regional Hydrothermal Systems, Regional Historic Earthquake Seismicity, Regional Temperature Gradient Data, Regional Heat Flow Data, Regional Radiogenic Heat Production, Local Geology, Land Status, Cultural Data, 2m Temperature Probe Data, and Gravity Data. Also a detailed down-hole lithology notes are provided.

  2. Corrosion reference for geothermal downhole materials selection: Overview

    SciTech Connect

    Ellis, Peter F.

    1982-10-08

    A consolidated reference of materials for downhole equipment used in geothermal energy exploitation is nearing completion. The reference is a summary of recent developments in the areas of tubular goods materials, highly alloyed metals, high temperature cements, high temperature elastomers, drilling and completion tools, logging tools, and downwell pumps. A brief overview is presented in this paper.

  3. Slim hole MWD tool accurately measures downhole annular pressure

    SciTech Connect

    Burban, B.; Delahaye, T. )

    1994-02-14

    Measurement-while-drilling of downhole pressure accurately determines annular pressure losses from circulation and drillstring rotation and helps monitor swab and surge pressures during tripping. In early 1993, two slim-hole wells (3.4 in. and 3 in. diameter) were drilled with continuous real-time electromagnetic wave transmission of downhole temperature and annular pressure. The data were obtained during all stages of the drilling operation and proved useful for operations personnel. The use of real-time measurements demonstrated the characteristic hydraulic effects of pressure surges induced by drillstring rotation in the small slim-hole annulus under field conditions. The interest in this information is not restricted to the slim-hole geometry. Monitoring or estimating downhole pressure is a key element for drilling operations. Except in special cases, no real-time measurements of downhole annular pressure during drilling and tripping have been used on an operational basis. The hydraulic effects are significant in conventional-geometry wells (3 1/2-in. drill pipe in a 6-in. hole). This paper describes the tool and the results from the field test.

  4. Downhole steam generator with improved preheating, combustion, and protection features

    DOEpatents

    Fox, R.L.

    1981-01-07

    For tertiary oil recovery, a downhole steam generator is designed which provides for efficient counterflow cooling of the combustion chamber walls and preheating of the fuel and water. Pressure-responsive doors are provided for closing and opening the outlet in response to flameout, thereby preventing flooding of the combustion chamber. (DLC)

  5. Piezoresistive cantilever force-clamp system

    SciTech Connect

    Park, Sung-Jin; Petzold, Bryan C.; Pruitt, Beth L.; Goodman, Miriam B.

    2011-04-15

    We present a microelectromechanical device-based tool, namely, a force-clamp system that sets or ''clamps'' the scaled force and can apply designed loading profiles (e.g., constant, sinusoidal) of a desired magnitude. The system implements a piezoresistive cantilever as a force sensor and the built-in capacitive sensor of a piezoelectric actuator as a displacement sensor, such that sample indentation depth can be directly calculated from the force and displacement signals. A programmable real-time controller operating at 100 kHz feedback calculates the driving voltage of the actuator. The system has two distinct modes: a force-clamp mode that controls the force applied to a sample and a displacement-clamp mode that controls the moving distance of the actuator. We demonstrate that the system has a large dynamic range (sub-nN up to tens of {mu}N force and nm up to tens of {mu}m displacement) in both air and water, and excellent dynamic response (fast response time, <2 ms and large bandwidth, 1 Hz up to 1 kHz). In addition, the system has been specifically designed to be integrated with other instruments such as a microscope with patch-clamp electronics. We demonstrate the capabilities of the system by using it to calibrate the stiffness and sensitivity of an electrostatic actuator and to measure the mechanics of a living, freely moving Caenorhabditis elegans nematode.

  6. An Ultrasonic Clamp for Bloodless Partial Nephrectomy

    NASA Astrophysics Data System (ADS)

    Lafon, Cyril; Bouchoux, Guillaume; Murat, François Joseph; Birer, Alain; Theillère, Yves; Chapelon, Jean Yves; Cathignol, Dominique

    2007-05-01

    Maximum conservation of the kidney is preferable through partial nephrectomy for patients at risk of disease recurrence of renal cancers. Haemostatic tools are needed in order to achieve bloodless surgery and reduce post surgery morbidity. Two piezo-ceramic transducers operating at a frequency of 4 MHz were mounted on each arm of a clamp. When used for coagulation purposes, two transducers situated on opposite arms of the clamp were driven simultaneously. Heat delivery was optimized as each transducers mirrored back to targeted tissues the wave generated by the opposite transducer. Real-time treatment monitoring with an echo-based technique was also envisaged with this clamp. Therapy was periodically interrupted so one transducer could generate a pulse. The echo returning from the opposite transducer was treated. Coagulation necroses were obtained in vitro on substantial thicknesses (23-38mm) of pig liver over exposure durations ranging from 30s to 130s, and with acoustic intensities of less than 15W/cm2 per transducer. Both kidneys of two pigs were treated in vivo with the clamp (14.5W/cm2 for 90s), and the partial nephrectomies performed proved to be bloodless. In vitro and in vivo, wide transfixing lesions corresponded to an echo energy decrease superior to -10dB and parabolic form of the time of flight versus treatment time. In conclusion, this ultrasound clamp has proven to be an excellent mean for achieving monitored haemostasis in kidney.

  7. Compact, Stiff, Remotely-Actuable Quick-Release Clamp

    NASA Technical Reports Server (NTRS)

    Tsai, Ted W. (Inventor)

    2000-01-01

    The present invention provides a clamp that is compact and lightweight, yet provides high holding strength and stiffness or rigidity. The clamp uses a unique double slant interface design which provides mechanical advantages to resist forces applied to the clamp member as the load increases. The clamp allows for rapid and remote-activated release of the clamp jaws by applying only a small operating force to an over-center lock/release mechanism, such as by pulling a manual tether.

  8. Comparative evaluation of surface and downhole steam-generation techniques

    SciTech Connect

    Hart, C.

    1982-01-01

    It has long been recognized that the application of heat to reservoirs containing high API gravity oils can substantially improve recovery. Although steam injection is currently the principal thermal recovery method, heat transmission losses associated with delivery of the steam from the surface generators to the oil-bearing formation has limited conventional steam injection to shallow reservoirs. The objective of the Department of Energy's Project DEEP STEAM is to develop the technology required to economically produce heavy oil from deep reservoirs. The tasks included in this effort are the development and evaluation of thermally efficient delivery systems and downhole steam generation systems. This paper compares the technical and economic performance of conventional surface steam drives, which are strongly influenced by heat losses, with (a) thermally efficient delivery (through insulated strings) of surface generated steam, (b) low pressure combustion downhole steam generation, (c) high pressure combustion downhole steam generation using air as the oxygen source, and (d) high pressure combustion downhole steam generation substituting pure oxygen for air. The selection of a preferred technology based upon either total efficiency or cost is found to be strongly influenced by reservoir depth, steam mass flow rate, and sandface steam quality. Therefore, a parametric analysis has been performed which examines varying depths, injection rates and steam qualities. Results indicate that the technologies are not readily distinguishable for low injectivity reservoirs in which conventional steam drives are feasible. However, high injection rates produce a notable cost difference between high pressure combustion systems and the other technologies. Issues that must be addressed before gaining further insight into the economic viability of downhole steam generation are discussed.

  9. Kinetic analysis of PCNA clamp binding and release in the clamp loading reaction catalyzed by Saccharomyces cerevisiae replication factor C

    PubMed Central

    Marzahn, Melissa R.; Hayner, Jaclyn N.; Meyer, Jennifer A.; Bloom, Linda B.

    2014-01-01

    DNA polymerases require a sliding clamp to achieve processive DNA synthesis. The toroidal clamps are loaded onto DNA by clamp loaders, members of the AAA+ family of ATPases. These enzymes utilize the energy of ATP binding and hydrolysis to perform a variety of cellular functions. In this study, a clamp loader-clamp binding assay was developed to measure the rates of ATP-dependent clamp binding and ATP-hydrolysis-dependent clamp release for the S. cerevisiae clamp loader (RFC) and clamp (PCNA). Pre-steady-state kinetics of PCNA binding showed that although ATP binding to RFC increases affinity for PCNA, ATP binding rates and ATP-dependent conformational changes in RFC are fast relative to PCNA binding rates. Interestingly, RFC binds PCNA faster than the Escherichia coli γ complex clamp loader binds the β-clamp. In the process of loading clamps on DNA, RFC maintains contact with PCNA while PCNA closes, as the observed rate of PCNA closing is faster than the rate of PCNA release, precluding the possibility of an open clamp dissociating from DNA. Rates of clamp closing and release are not dependent on the rate of the DNA binding step and are also slower than reported rates of ATP hydrolysis, showing that these rates reflect unique intramolecular reaction steps in the clamp loading pathway. PMID:25450506

  10. Downhole cleaner assembly for cleansing lubricant of downhole turbo-machines within wells

    SciTech Connect

    Erickson, J.W.; Petrie, H.L.

    1981-04-28

    While in a well, a downhole turbo-machine of a series of turbine stages and pump stages is driven by power fluid circulated into the turbine stages from the surface. A branch stream from the power fluid passes through a centrifugal cleaner and is cleansed of solid material. The turbine stages drive the centrifugal cleaner. The cleansed stream becomes lubricant for the turbomachine bearings. On the turbine side, the lubricant stream passes at substantially cleaner discharge pressure into longitudinal passages between turbine shrouds and an alignment tube to journal bearings and journals located between turbine stage stators and a drive shaft driven by the turbines. Annular channels between separate shrouds effect communication between the longitudinal passages between the shrouds and the alignment tube. On the pump side, the lubricant stream is first directed so that it can act on a thrust bearing runner and apply a force in opposition to an otherwise unbalanced axial force. A low pressure discharge from the thrust bearing runner supplies galleries that feed journal and journal bearings of the pump stage stators. Gallery pressure is maintained positive with respect to the pump stage bearings by a feed to the gallery in excess of bleed-out of the bearings. A check valve relieves any excess gallery pressure to that of the next to the last turbine stage fluid passage. Lubricant bleeds from the journals and journal bearings into the fluid stream passing through the turbine pumps.

  11. Limit analysis of pipe clamps. Revision 1

    SciTech Connect

    Flanders, H.E. Jr.

    1990-12-31

    The Service Level D (faulted) load capacity of a conventional three-bolt pipe-clamp based upon the limit analysis method is presented. The load distribution, plastic hinge locations, and collapse load are developed for the lower bound limit load method. The results of the limit analysis are compared with the manufacturer`s rated loads. 3 refs.

  12. Clamp and Gas Nozzle for TIG Welding

    NASA Technical Reports Server (NTRS)

    Gue, G. B.; Goller, H. L.

    1982-01-01

    Tool that combines clamp with gas nozzle is aid to tungsten/inert-gas (TIG) welding in hard-to-reach spots. Tool holds work to be welded while directing a stream of argon gas at weld joint, providing an oxygen-free environment for tungsten-arc welding.

  13. Piezoresistive cantilever force-clamp system

    PubMed Central

    Park, Sung-Jin; Petzold, Bryan C.; Goodman, Miriam B.; Pruitt, Beth L.

    2011-01-01

    We present a microelectromechanical device-based tool, namely, a force-clamp system that sets or “clamps” the scaled force and can apply designed loading profiles (e.g., constant, sinusoidal) of a desired magnitude. The system implements a piezoresistive cantilever as a force sensor and the built-in capacitive sensor of a piezoelectric actuator as a displacement sensor, such that sample indentation depth can be directly calculated from the force and displacement signals. A programmable real-time controller operating at 100 kHz feedback calculates the driving voltage of the actuator. The system has two distinct modes: a force-clamp mode that controls the force applied to a sample and a displacement-clamp mode that controls the moving distance of the actuator. We demonstrate that the system has a large dynamic range (sub-nN up to tens of μN force and nm up to tens of μm displacement) in both air and water, and excellent dynamic response (fast response time, <2 ms and large bandwidth, 1 Hz up to 1 kHz). In addition, the system has been specifically designed to be integrated with other instruments such as a microscope with patch-clamp electronics. We demonstrate the capabilities of the system by using it to calibrate the stiffness and sensitivity of an electrostatic actuator and to measure the mechanics of a living, freely moving Caenorhabditis elegans nematode. PMID:21529009

  14. Lotung downhole array. 2: Evaluation of soil nonlinear properties

    SciTech Connect

    Zeghal, M.; Elgamal, A.W.; Tang, H.T.; Stepp, J.C.

    1995-04-01

    The characteristics of soil response during earthquake excitations, at a site in Lotung, Taiwan are identified using the Lotung large scale seismic test (LSST) data. A technique is developed to evaluate soil shear stress-strain histories directly from the free-field downhole accelerations. These histories are used to estimate variation of soil shear moduli and material damping characteristics with shear strain amplitude, and to assess the effects of pore pressure buildup. Soil stiffness properties are found to compare satisfactorily with those obtained through laboratory tests conducted by the University of California, Davis; the National Taiwan University; and the University of Texas at Austin. Pore pressure buildup appears to be accompanied by a reduction in soil stiffness. The information obtained in this study demonstrates that downhole accelerometer and pore pressure arrays offer a direct effective means of evaluating seismic soil properties.

  15. Lotung downhole array. 1: Evaluation of site dynamic properties

    SciTech Connect

    Elgamal, A.W.; Zeghal, M.; Tang, H.T.; Stepp, J.C.

    1995-04-01

    The Lotung large-scale seismic test (LSST) site in Taiwan was instrumented in 1985 with an array of downhole and surface accelerometers, by the Electric Power Research Institute (EPRI), Palo Alto, California, and the Taiwan Power Company (TPC), Taipei, Taiwan. A total of 18 earthquakes were recorded during the period 1985--86. Correlation and spectral analyses of the recorded downhole accelerations are performed to evaluate shear wave propagation characteristics, variation of shear wave velocity with depth, and site resonant frequencies and modal configurations. A shear-beam model, calibrated by the identified site properties, is found to represent the site dynamic response characteristics over a wide frequency range. In a companion paper, strong-motion earthquake records are utilized to investigate the Lotung site large-strain soil response characteristics.

  16. Active cooling for downhole instrumentation: Preliminary analysis and system selection

    SciTech Connect

    Bennett, G.A.

    1988-03-01

    A feasibility study and a series of preliminary designs and analyses were done to identify candidate processes or cycles for use in active cooling systems for downhole electronic instruments. A matrix of energy types and their possible combinations was developed and the energy conversion process for each pari was identified. The feasibility study revealed conventional as well as unconventional processes and possible refrigerants and identified parameters needing further clarifications. A conceptual design or series od oesigns for each system was formulated and a preliminary analysis of each design was completed. The resulting coefficient of performance for each system was compared with the Carnot COP and all systems were ranked by decreasing COP. The system showing the best combination of COP, exchangeability to other operating conditions, failure mode, and system serviceability is chosen for use as a downhole refrigerator. 85 refs., 48 figs., 33 tabs.

  17. High power laser downhole cutting tools and systems

    SciTech Connect

    Zediker, Mark S; Rinzler, Charles C; Faircloth, Brian O; Koblick, Yeshaya; Moxley, Joel F

    2015-01-20

    Downhole cutting systems, devices and methods for utilizing 10 kW or more laser energy transmitted deep into the earth with the suppression of associated nonlinear phenomena. Systems and devices for the laser cutting operations within a borehole in the earth. These systems and devices can deliver high power laser energy down a deep borehole, while maintaining the high power to perform cutting operations in such boreholes deep within the earth.

  18. Apparatus and method for downhole injection of radioactive tracer

    DOEpatents

    Potter, Robert M.; Archuleta, Jacobo R.; Fink, Conrad F.

    1983-01-01

    The disclosure relates to downhole injection of radioactive .sup.82 Br and monitoring its progress through fractured structure to determine the nature thereof. An ampule containing granular .sup.82 Br is remotely crushed and water is repeatedly flushed through it to cleanse the instrument as well as inject the .sup.82 Br into surrounding fractured strata. A sensor in a remote borehole reads progress of the radioactive material through fractured structure.

  19. Apparatus and method for downhole injection of radioactive tracer

    DOEpatents

    Potter, R.M.; Archuleta, J.; Fink, C.F.

    The disclosure relates to downhole injection of radioactive /sup 82/Br and monitoring its progress through fractured structure to determine the nature thereof. An ampule containing granular /sup 82/Br is remotely crushed and water is repeatedly flushed through it to cleanse the instrument as well as inject the /sup 82/Br into surrounding fractured strata. A sensor in a remote horehole reads progress of the radioactive material through fractured structure.

  20. Downhole steam-generator study. Volume 2: Design summary

    NASA Astrophysics Data System (ADS)

    1982-06-01

    A detailed design of a low pressure combustion, indirect contact, downhole steam generator was prepared. The design is based on analysis and experiments conducted previously (reported in Vol. I). The generator is sized to operate in a 7-inch casing and deliver 350 bbl/d of 80% quality steam at a pressure of 1500 psia. Included in this report are a description of the design, the expected range of operating conditions, and a suggested installation procedure.

  1. Downhole steam-generator study. Volume II. Design summary

    SciTech Connect

    Not Available

    1982-06-01

    A detailed design of a low pressure combustion, indirect contact, downhole steam generator was prepared. The design is based on analysis and experiments conducted previously (reported in Vol. I). The generator is sized to operate in a 7-inch casing and deliver 350 bbl/d of 80% quality steam at a pressure of 1500 psia. Included in this report are a description of the design, the expected range of operating conditions, and a suggested installation procedure.

  2. Use of Downhole Motors in Geothermal Drilling in the Philippines

    SciTech Connect

    Pyle, D. E.

    1981-01-01

    This paper describes the use of downhole motors in the Tiwi geothermal field in the Philippines, The discussion includes the application Of a Dyna-Drill with insert-type bits for drilling through surface alluvium. The economics of this type of drilling are compared to those of conventional rotary drilling. The paper also describes the use of a turbodrill that drills out scale as the well produces geothermal fluids.

  3. System for loading executable code into volatile memory in a downhole tool

    DOEpatents

    Hall, David R.; Bartholomew, David B.; Johnson, Monte L.

    2007-09-25

    A system for loading an executable code into volatile memory in a downhole tool string component comprises a surface control unit comprising executable code. An integrated downhole network comprises data transmission elements in communication with the surface control unit and the volatile memory. The executable code, stored in the surface control unit, is not permanently stored in the downhole tool string component. In a preferred embodiment of the present invention, the downhole tool string component comprises boot memory. In another embodiment, the executable code is an operating system executable code. Preferably, the volatile memory comprises random access memory (RAM). A method for loading executable code to volatile memory in a downhole tool string component comprises sending the code from the surface control unit to a processor in the downhole tool string component over the network. A central processing unit writes the executable code in the volatile memory.

  4. Fate of hydraulic fracturing chemicals under down-hole conditions

    NASA Astrophysics Data System (ADS)

    Blotevogel, J.; Kahrilas, G.; Corrin, E. R.; Borch, T.

    2013-12-01

    Hydraulic fracturing is a method to increase the yield of oil and natural gas extraction from unconventional rock formations. The process of hydrofracturing occurs via injecting water, sand, and chemicals into the production well and subjecting this mixture to high pressures to crack the rock shale, allowing increased amounts of gas and oil to seep out of the target formation. Typical constituents of the chemical mixtures are biocides, which are applied to inhibit growth of sulfate reducing bacteria in order to prevent pipe corrosion and production of hazardous gases. However, very little is known about the persistence, fate, and activity of biocides when subjected to the high temperatures and pressures of down-hole conditions. Thus, the objective of this talk is to present data from ongoing experiments focused on determining the fate of biocides commonly used for hydraulic fracturing under conditions simulating down-hole environments. Using stainless steel reactors, the high pressures and temperatures of down-hole conditions in the Marcellus shale are simulated, while concentration, speciation, and degradation of priority biocides are observed as a function of time, using primarily LC/MS techniques. The impact of water quality, shale, temperature, and pressure on the transformation kinetics and pathways of biocides will be discussed. Finally, field samples (both sediments and flowback brine) from the Marcellus shale are analyzed to verify that our lab simulations mirror real-life conditions and results.

  5. Prediction of the combustion characteristics in a downhole steam generator

    SciTech Connect

    Naugler, David G.; Mohtadi, M. F.

    1984-02-01

    Downhole steam generation is an attractive alternative to conventional surface steam generation for recovery of heavy oils from deep reservoirs. Downhole steam generation technique has been under development in the past five years in the United States, Canada and the United Kingdom. The main advantages of this method are very high thermal efficiency, flexibility of operation and lower environmental pollution load. In conjunction with experimental work on the development of a downhole steam generator at the University of Calgary, two computer models for prediction of the combustion characteristics in such generators have been developed. The first model is based on the assumption of a balanced reaction and complete combustion of the fuel. It determines the reaction temperature and the enthalpy of the product gases at different pressures, air/fuel ratios and water injection rates. The second model uses a modified version of the Dixon Lewis method to determine equilibrium for all species of the reaction system, including nitrogen oxides. A non-Jacobian numerical method is used for the solution of the resulting system of non-linear equations. The results show that to a fairly good approximation, the reaction temperature and the composition of product gases may be correlated with the main operating variables by simple logarithmic plots. This facilitates extrapolation of the experimental data by the use of allocation transformations.

  6. Geothermal cement: high temperature downhole tests: continuation of an API project

    SciTech Connect

    Pettitt, R.A.; Rowley, J.C.

    1983-08-01

    A research program, funded by DOE, on developing geothermal cement mixtures that will give optimum qualities under harsh downhole conditions is discussed. Downhole static tests and downhole pumpdown tests are described. This program will lead to the determination of suitable high-temperature cement mixtures, with improved strength, durability and pumpability characteristics for the completion and repair of wells in a corrosive fluid environment at very high temperatures.

  7. Electrical cable connector-clamp has smooth exterior surface

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Electrical cable connector-clamp fitted with a collet has a smooth exterior surface that can be easily gripped. The collet clamps a portion of the cable and provides for connecting it to a standard electrical connector.

  8. Comparative analysis of steam delivery cost for surface and downhole steam drive technologies

    SciTech Connect

    Hart, C.M.

    1981-10-01

    A basis is established for evaluating the economic performances of the technologies for enhanced recovery of heavy crude being investigated through the Department of Energy's Project DEEP STEAM. Conventional surface steam drive is compared with: (1) thermally efficient delivery (through insulated strings) of surface generated steam; (2) low pressure combustion downhole steam generation; (3) high pressure combustion downhole steam generation; (4) high pressure combustion downhole steam generation using air as the oxygen source; and (5) high pressure combustion downhole steam generation substituting pure oxygen for air. A parametric analysis is performed for varying depths, injection rates, and steam qualities.

  9. Mechanical and metallurgical properties of carotid artery clamps.

    PubMed

    Dujovny, M; Kossovsky, N; Kossowsky, R; Segal, R; Diaz, F G; Kaufman, H; Perlin, A; Cook, E E

    1985-11-01

    The mechanical and metallurgical properties of carotid artery clamps were evaluated. The pressure plate retreat propensity, metallurgical composition, surface morphology, magnetic properties, and corrosion resistance of the Crutchfield, Selverstone, Salibi, and Kindt clamps were tested. None of the clamps showed evidence of pressure plate retreat. The clamps differed significantly in their composition, surface cleanliness, magnetic properties, and corrosion resistance. The Crutchfield clamp was the only one manufactured from an ASTM-ANSI-approved implantable stainless steel (AISI 316) and the only clamp in which the surfaces were clean and free of debris. The Selverstone clamp was made principally from AISI 304 stainless steel, as was one Salibi clamp. The pressure plate on another Salibi clamp was made from a 1% chromium and 1% manganese steel. Machining and surface debris consisting principally of aluminum, silicon, and sulfur was abundant on the Selverstone and Salibi clamps. The Kindt clamp was manufactured from AISI 301 stainless steel with a silicate-aluminized outer coating. The Crutchfield and Selverstone clamps were essentially nonferromagnetic, whereas the Salibi and Kindt clamps were sensitive to magnetic flux. In the pitting potential corrosion test, the Crutchfield clamp demonstrated good corrosion resistance with a pitting potential of 310 mV and no surface corrosion or pitting by scanning electron microscopy examination. The Selverstone clamp had lower pitting potentials and showed various degrees of corrosion and surface pitting by scanning electron microscopy. The Salibi pressure plate had a very low pitting potential of -525 mV and showed severe corrosion. By metallurgical criteria, only the Crutchfield clamp is suitable for long term implantation. PMID:4069328

  10. 30 CFR 18.40 - Cable clamps and grips.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Requirements § 18.40 Cable clamps and grips. Insulated clamps shall be provided for all portable (trailing) cables to prevent strain on the cable terminals of a machine. Also insulated clamps shall be provided to... mounted component. Cable grips anchored to the cable may be used in lieu of insulated strain...

  11. 30 CFR 18.40 - Cable clamps and grips.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Requirements § 18.40 Cable clamps and grips. Insulated clamps shall be provided for all portable (trailing) cables to prevent strain on the cable terminals of a machine. Also insulated clamps shall be provided to... mounted component. Cable grips anchored to the cable may be used in lieu of insulated strain...

  12. 30 CFR 18.40 - Cable clamps and grips.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Requirements § 18.40 Cable clamps and grips. Insulated clamps shall be provided for all portable (trailing) cables to prevent strain on the cable terminals of a machine. Also insulated clamps shall be provided to... mounted component. Cable grips anchored to the cable may be used in lieu of insulated strain...

  13. 30 CFR 18.40 - Cable clamps and grips.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Requirements § 18.40 Cable clamps and grips. Insulated clamps shall be provided for all portable (trailing) cables to prevent strain on the cable terminals of a machine. Also insulated clamps shall be provided to... mounted component. Cable grips anchored to the cable may be used in lieu of insulated strain...

  14. Single molecule study of a processivity clamp sliding on DNA

    SciTech Connect

    Laurence, T A; Kwon, Y; Johnson, A; Hollars, C; O?Donnell, M; Camarero, J A; Barsky, D

    2007-07-05

    Using solution based single molecule spectroscopy, we study the motion of the polIII {beta}-subunit DNA sliding clamp ('{beta}-clamp') on DNA. Present in all cellular (and some viral) forms of life, DNA sliding clamps attach to polymerases and allow rapid, processive replication of DNA. In the absence of other proteins, the DNA sliding clamps are thought to 'freely slide' along the DNA; however, the abundance of positively charged residues along the inner surface may create favorable electrostatic contact with the highly negatively charged DNA. We have performed single-molecule measurements on a fluorescently labeled {beta}-clamp loaded onto freely diffusing plasmids annealed with fluorescently labeled primers of up to 90 bases. We find that the diffusion constant for 1D diffusion of the {beta}-clamp on DNA satisfies D {le} 10{sup -14} cm{sup 2}/s, much slower than the frictionless limit of D = 10{sup -10} cm{sup 2}/s. We find that the {beta} clamp remains at the 3-foot end in the presence of E. coli single-stranded binding protein (SSB), which would allow for a sliding clamp to wait for binding of the DNA polymerase. Replacement of SSB with Human RP-A eliminates this interaction; free movement of sliding clamp and poor binding of clamp loader to the junction allows sliding clamp to accumulate on DNA. This result implies that the clamp not only acts as a tether, but also a placeholder.

  15. π-Clamp Mediated Cysteine Conjugation

    PubMed Central

    Zhang, Chi; Welborn, Matthew; Zhu, Tianyu; Yang, Nicole J.; Santos, Michael S.; Van Voorhis, Troy; Pentelute, Bradley L.

    2016-01-01

    Site-selective functionalization of complex molecules is a grand challenge in chemistry. Protecting groups or catalysts must be used to selectively modify one site among many that are similarly reactive. General strategies are rare such the local chemical environment around the target site is tuned for selective transformation. Here we show a four amino acid sequence (Phe-Cys-Pro-Phe), which we call the “π-clamp”, tunes the reactivity of its cysteine thiol for the site-selective conjugation with perfluoroaromatic reagents. We used the π-clamp to selectively modify one cysteine site in proteins containing multiple endogenous cysteine residues (e.g. antibodies and cysteine-based enzymes), which was impossible with prior cysteine modification methods. The modified π-clamp antibodies retained binding affinity to their targets, enabling the synthesis of site-specific antibody-drug conjugates (ADCs) for selective killing of HER2-positive breast cancer cells. The π-clamp is an unexpected approach for site-selective chemistry and provides opportunities to modify biomolecules for research and therapeutics. PMID:26791894

  16. Temperature-Controlled Clamping and Releasing Mechanism

    NASA Technical Reports Server (NTRS)

    Rosing, David; Ford, Virginia

    2005-01-01

    A report describes the development of a mechanism that automatically clamps upon warming and releases upon cooling between temperature limits of approx. =180 K and approx. =293 K. The mechanism satisfied a need specific to a program that involved repeated excursions of a spectrometer between a room-temperature atmospheric environment and a cryogenic vacuum testing environment. The mechanism was also to be utilized in the intended application of the spectrometer, in which the spectrometer would be clamped for protection during launch of a spacecraft and released in the cold of outer space to allow it to assume its nominal configuration for scientific observations. The mechanism is passive in the sense that its operation does not depend on a control system and does not require any power other than that incidental to heating and cooling. The clamping and releasing action is effected by bolt-preloaded stacks of shape-memory-alloy (SMA) cylinders. In designing this mechanism, as in designing other, similar SMA mechanisms, it was necessary to account for the complex interplay among thermal expansion, elastic and inelastic deformation under load, and SMA thermomechanical properties.

  17. Carbon nanotube-clamped metal atomic chain

    PubMed Central

    Tang, Dai-Ming; Yin, Li-Chang; Li, Feng; Liu, Chang; Yu, Wan-Jing; Hou, Peng-Xiang; Wu, Bo; Lee, Young-Hee; Ma, Xiu-Liang; Cheng, Hui-Ming

    2010-01-01

    Metal atomic chain (MAC) is an ultimate one-dimensional structure with unique physical properties, such as quantized conductance, colossal magnetic anisotropy, and quantized magnetoresistance. Therefore, MACs show great potential as possible components of nanoscale electronic and spintronic devices. However, MACs are usually suspended between two macroscale metallic electrodes; hence obvious technical barriers exist in the interconnection and integration of MACs. Here we report a carbon nanotube (CNT)-clamped MAC, where CNTs play the roles of both nanoconnector and electrodes. This nanostructure is prepared by in situ machining a metal-filled CNT, including peeling off carbon shells by spatially and elementally selective electron beam irradiation and further elongating the exposed metal nanorod. The microstructure and formation process of this CNT-clamped MAC are explored by both transmission electron microscopy observations and theoretical simulations. First-principles calculations indicate that strong covalent bonds are formed between the CNT and MAC. The electrical transport property of the CNT-clamped MAC was experimentally measured, and quantized conductance was observed. PMID:20427743

  18. π-Clamp-mediated cysteine conjugation

    NASA Astrophysics Data System (ADS)

    Zhang, Chi; Welborn, Matthew; Zhu, Tianyu; Yang, Nicole J.; Santos, Michael S.; van Voorhis, Troy; Pentelute, Bradley L.

    2016-02-01

    Site-selective functionalization of complex molecules is one of the most significant challenges in chemistry. Typically, protecting groups or catalysts must be used to enable the selective modification of one site among many that are similarly reactive, and general strategies that selectively tune the local chemical environment around a target site are rare. Here, we show a four-amino-acid sequence (Phe-Cys-Pro-Phe), which we call the ‘π-clamp’, that tunes the reactivity of its cysteine thiol for site-selective conjugation with perfluoroaromatic reagents. We use the π-clamp to selectively modify one cysteine site in proteins containing multiple endogenous cysteine residues. These examples include antibodies and cysteine-based enzymes that would be difficult to modify selectively using standard cysteine-based methods. Antibodies modified using the π-clamp retained binding affinity to their targets, enabling the synthesis of site-specific antibody-drug conjugates for selective killing of HER2-positive breast cancer cells. The π-clamp is an unexpected approach to mediate site-selective chemistry and provides new avenues to modify biomolecules for research and therapeutics.

  19. Condition of chromic acid anodized aluminum clamps flown

    NASA Technical Reports Server (NTRS)

    Plagemann, W. L.

    1991-01-01

    A survey of the condition of the chromic acid anodized (CAA) coating on selected LDEF tray clamps was carried out. Measurements of solar absorptance and thermal emittance were carried out at multiple locations on both the space exposed and spacecraft facing sides of the clamps. Multiple clamps from each available angle relative to the ram direction were examined. The diffuse component of the reflectance spectrum was measured for a selected subset of the clamps. The thickness of the CAA was determined for a small set of clamps. Examples of variation in integrity of the coatings from leading to trailing edge will be shown.

  20. A mathematical model for the downhole orbital vibrator source

    SciTech Connect

    Dong, W.

    1994-12-31

    An analytical expression for the downhole orbital vibrator source is proposed by approximating the source as rotating radial forces applied to the borehole wall. Decomposition of this expression indicates that the source is equivalent to the sum of four imaginary non-rotational sources. These imaginary sources, in conjunction with Green`s functions, provide a direct way of generating synthetic seismograms. They are used in this paper to obtain the displacement in homogeneous isotropic and transversely isotropic (TI) media. Evaluation of the displacement suggests that the source would be useful in detecting shear wave anisotropy by crosshole experiments.

  1. Steam drive recovery method utilizing a downhole steam generator

    SciTech Connect

    Snavely, E. S.; Hopkins, D. N.

    1984-09-18

    Viscous oil is recovered from a subterranean, viscous oil-containing formation by a steam flooding technique wherein steam is generated in a downhole steam generator located in an injection well by spontaneous combustion of a pressurized mixture of a water-soluble fuel such as sugars and alcohols dissolved in water and substantially pure oxygen. The generated mixture of steam and combustion gases pass through the formation, displacing oil and reducing the oil's viscosity and the mobilized oil is produced from the formation via a spaced-apart production well.

  2. Steam drive oil recovery method utilizing a downhole steam generator

    SciTech Connect

    Nopkins, D. N.; Snavely, E. S.

    1984-10-23

    Viscous oil is recovered from a subterranean, viscous oil-containing formation by a steam flooding technique wherein steam is generated in a downhole steam generator located in an injection well by spontaneous combustion of a pressurized mixture of a water-soluble fuel such as sugars and alcohols dissolved in water or a stable hydrocarbon fuel-in-water emulsion and substantially pure oxygen. The generated mixture of steam and combustion gases pass through the formation, displacing oil and reducing the oil's viscosity and the mobilized oil is produced from the formation via a spaced-apart production well.

  3. Working member of a helical downhole motor for drilling wells

    SciTech Connect

    Kochnev, A.M.; Vshivkov, A.N.; Goldobin, V.B.

    1993-06-22

    A working member of a helical downhole motor is described for drilling wells comprising: separate tubular sections having helical teeth arranged in succession and interconnected by connecting elements, each connecting element having the form of a ring, rigidly secured at the tubular sections and having helical teeth of a pitch and a direction equal to a pitch and a direction, respectively, of the helical teeth of the tubular sections, whereas a profile of the helical teeth of the ring is equidistant to a profile of the helical teeth of the sections.

  4. Experiment 2030. EE-2 Temperature Log and Downhole Water Sample

    SciTech Connect

    Grigsby, Charles O.

    1983-07-29

    A temperature log and downhole water sample run were conducted in EE-2 on July 13, 1983. The temperature log was taken to show any changes which had occurred in the fracture-to-wellbore intersections as a result of the Experiment 2020 pumping and to locate fluid entries for taking the water sample. The water sample was requested primarily to determine the arsenic concentration in EE-2 fluids (see memo from C.Grigsby, June 28, 1983 concerning arsenic in EE-3 samples.) The temperature log was run using the thermistor in the ESS-6 water samples.

  5. Inductive coupler for downhole components and method for making same

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Sneddon, Cameron; Fox, Joe; Briscoe, Michael A.

    2006-10-03

    An inductive coupler for downhole components. The inductive coupler includes an annular housing having a recess defined by a bottom portion and two opposing side wall portions. At least one side wall portion includes a lip extending toward but not reaching the other side wall portion. A plurality of generally U-shaped MCEI segments, preferably comprised of ferrite, are disposed in the recess and aligned so as to form a circular trough. The coupler further includes a conductor disposed within the circular trough and a polymer filling spaces between the segments, the annular housing and the conductor.

  6. Biological cell controllable patch-clamp microchip

    NASA Astrophysics Data System (ADS)

    Penmetsa, Siva; Nagrajan, Krithika; Gong, Zhongcheng; Mills, David; Que, Long

    2010-12-01

    A patch-clamp (PC) microchip with cell sorting and positioning functions is reported, which can avoid drawbacks of random cell selection or positioning for a PC microchip. The cell sorting and positioning are enabled by air bubble (AB) actuators. AB actuators are pneumatic actuators, in which air pressure is generated by microheaters within sealed microchambers. The sorting, positioning, and capturing of 3T3 cells by this type of microchip have been demonstrated. Using human breast cancer cells MDA-MB-231 as the model, experiments have been demonstrated by this microchip as a label-free technical platform for real-time monitoring of the cell viability.

  7. Laser-assisted patch clamping: a methodology

    NASA Technical Reports Server (NTRS)

    Henriksen, G. H.; Assmann, S. M.; Evans, M. L. (Principal Investigator)

    1997-01-01

    Laser microsurgery can be used to perform both cell biological manipulations, such as targeted cell ablation, and molecular genetic manipulations, such as genetic transformation and chromosome dissection. In this report, we describe a laser microsurgical method that can be used either to ablate single cells or to ablate a small area (1-3 microns diameter) of the extracellular matrix. In plants and microorganisms, the extracellular matrix consists of the cell wall. While conventional patch clamping of these cells, as well as of many animal cells, requires enzymatic digestion of the extracellular matrix, we illustrate that laser microsurgery of a portion of the wall enables patch clamp access to the plasma membrane of higher plant cells remaining situated in their tissue environment. What follows is a detailed description of the construction and use of an economical laser microsurgery system, including procedures for single cell and targeted cell wall ablation. This methodology will be of interest to scientists wishing to perform cellular or subcellular ablation with a high degree of accuracy, or wishing to study how the extracellular matrix affects ion channel function.

  8. ClampOn acoustic solid fuel monitor

    SciTech Connect

    Vesterhus, T.

    1999-07-01

    The general idea of the project is to develop a ClampOn Solid Fuel Monitor, enabling optimization of the combustion process in pulverized coal fired boilers. The development will be based on adapting existing technology for measuring the content of sand particles in a flow of natural gas. The Norwegian firm ClampOn AS develops equipment for such measurements, and has already a proven track record as a result of its work with major oil companies throughout the world. The industry wants some sort of fuel indicator, e.g. a piece of equipment that enables the operator to measure and control the amounts of the fuel to each individual burner. The best techniques available today--as far as the author knows--can only offer samples of the fuel stream at discrete points of time. To truly optimize the combustion process, it is vital to continuously monitor the mass of fuel to each burner, and optimize the combustion process through continuous and infinitesimal adjustments of the fuel flow. This will minimize the NO{sub x} created by uneven temperature-distribution in the combustion chamber. In this way maximum power generation can be obtained at minimal emission of pollutants for a given amount of coal burned.

  9. Characterization of the clamp pressure of electrostatic chucks

    NASA Astrophysics Data System (ADS)

    Ziemann, M.; Voss, S.; Baldus, O.; Schmidt, V.

    2010-04-01

    Berliner Glas KGaA is specialized on the manufacturing of high performance wafer and reticle chucks. Electrostatic chucks (ESC) are especially used in vacuum environments e.g. during lithographic processing, coating and etching. The main task of the chuck is to provide a well defined positioning and thermal stabilization of the wafer or reticle. Typical wafer materials are semiconductors like silicon and in some special cases dielectrics like magnesia, alumina or glass. For a functional characterization of the ESC clamps Berliner Glas has developed a measurement method to determine the clamp pressure with a Fizeau interferometer. The setup utilizes the local bending of clamped wafers to determine the effective clamp pressure. The clamp pressure is measured in the range of 20...500 mbar. This new method allows for a lateral resolution of the clamp pressure measurement. It can be calibrated by various methods. Direct computation of the clamp pressure based on the bending height or comparative measurements with vacuum chucking by the same chuck gives evidence for the quantitative results. Transient clamp pressure variation can be measured with a resolution of 2 mbar. The results can be used to qualify and optimize ESĆs and even for a local correction of the clamp force.

  10. An Optimal Cell Detection Technique for Automated Patch Clamping

    NASA Technical Reports Server (NTRS)

    McDowell, Mark; Gray, Elizabeth

    2004-01-01

    While there are several hardware techniques for the automated patch clamping of cells that describe the equipment apparatus used for patch clamping, very few explain the science behind the actual technique of locating the ideal cell for a patch clamping procedure. We present a machine vision approach to patch clamping cell selection by developing an intelligent algorithm technique that gives the user the ability to determine the good cell to patch clamp in an image within one second. This technique will aid the user in determining the best candidates for patch clamping and will ultimately save time, increase efficiency and reduce cost. The ultimate goal is to combine intelligent processing with instrumentation and controls in order to produce a complete turnkey automated patch clamping system capable of accurately and reliably patch clamping cells with a minimum amount of human intervention. We present a unique technique that identifies good patch clamping cell candidates based on feature metrics of a cell's (x, y) position, major axis length, minor axis length, area, elongation, roundness, smoothness, angle of orientation, thinness and whether or not the cell is only particularly in the field of view. A patent is pending for this research.

  11. Spectral infrared hemispherical reflectance measurements for LDEF tray clamps

    NASA Technical Reports Server (NTRS)

    Cromwell, B. K.; Shepherd, S. D.; Pender, C. W.; Wood, B. E.

    1993-01-01

    Infrared hemispherical reflectance measurements that were made on 58 chromic acid anodized tray clamps from LDEF are described. The measurements were made using a hemiellipsoidal mirror reflectometer with interferometer for wavelengths between 2-15 microns. The tray clamps investigated were from locations about the entire spacecraft and provided the opportunity for comparing the effects of atomic oxygen at each location. Results indicate there was essentially no dependence on atomic oxygen fluence for the surfaces studied, but there did appear to be a slight dependence on solar radiation exposure. The reflectances of the front sides of the tray clamps consistently were slightly higher than for the protected rear tray clamp surfaces.

  12. Re-visiting the trans insertion model for complexin clamping.

    PubMed

    Krishnakumar, Shyam S; Li, Feng; Coleman, Jeff; Schauder, Curtis M; Kümmel, Daniel; Pincet, Frederic; Rothman, James E; Reinisch, Karin M

    2015-01-01

    We have previously proposed that complexin cross-links multiple pre-fusion SNARE complexes via a trans interaction to function as a clamp on SNARE-mediated neurotransmitter release. A recent NMR study was unable to detect the trans clamping interaction of complexin and therefore questioned the previous interpretation of the fluorescence resonance energy transfer and isothermal titration calorimetry data on which the trans clamping model was originally based. Here we present new biochemical data that underscore the validity of our previous interpretation and the continued relevancy of the trans insertion model for complexin clamping. PMID:25831964

  13. Gas Hydrate Research Coring and Downhole Logging Operational Protocol

    NASA Astrophysics Data System (ADS)

    Collett, T. S.; Riedel, M.; Malone, M.

    2006-12-01

    Recent gas hydrate deep coring and downhole logging projects, including ODP Leg 204, IODP Expedition 311, and the India NGHP-01 effort have contributed greatly to our understanding of the geologic controls on the occurrence of gas hydrate. These projects have also built on the relatively sparse history of gas hydrate drilling experience to collectively develop a unique operational protocol to examine and sample gas hydrate in nature. The ideal gas hydrate research drill site in recent history, consists of at least three drill holes, with the first hole dedicated to LWD/MWD downhole logging in order to identify intervals to be pressurized cored and to collect critical petrophysical data. The second hole is usually dedicated for continuous coring operations. The third hole is used for special downhole tool measurements such as pressure coring and wire line logging. There is a strong scientific need to obtain LWD/MWD data prior to coring. The coring operations are complemented by frequent deployment of the PCS/HYACINTH pressure core systems. It is essential to know what the gas hydrate concentrations and vertical distribution are before deploying the available pressure core systems in order to choose the optimum depths for pressure coring operations. The coring operations are also complemented by frequent sampling for interstitial water, headspace gas, and microbiological analyses. Although those samples will be taken at relatively regular depths, the sampling frequency can be adjusted if gas hydrate concentrations and distribution can be forward predicted through the analysis of the LWD/MWD pre-core logging surveys. After completing the LWD/MWD logging program, usually as a dedicated drilling leg, field efforts will switch to conventional and pressure-controlled coring operations at each of the sites drilled during the LWD/MWD campaign. The standard continuous core hole will usually include APC coring to an expected refusal depth of ~100 mbsf; each hole is usually

  14. Voltage clamp experiments on ventricular myocarial fibres.

    PubMed

    Beeler, G W; Reuter, H

    1970-03-01

    1. A voltage clamp method utilizing a sucrose gap and glass microelectrodes was developed and used to study dog ventricular myocardial fibre bundles. The limitations and the reliability of this method are demonstrated by a series of tests.2. A dynamic sodium current, excited at membrane potentials more positive than -65 mV, was measured. The equilibrium potential for this large, rapid inward current depends directly on [Na](o), shifting 29.0 +/- 2.3 mV (+/- S.E. of mean), as opposed to a theoretically expected value of 30.6 mV, when [Na](o) is reduced to 31% of normal.3. Sodium current is inactivated by conditioning depolarizations. Complete inactivation occurs with conditioning potentials more positive than -45 mV, and 50% inactivation occurs at about -55 mV. The location of the inactivation curve shifts along the voltage axis, when [Ca](o) is varied between 0.2 and 7.2 mM.4. A second, much smaller and slower net inward current, with a threshold around -30 mV, and an equilibrium potential above +40 mV was also observed.5. The ;steady-state' current-voltage relationship (after 300-600 msec) exhibits inward-going (anomalous) rectification with negative slope between -50 and -25 mV.6. A small, very slowly developing component of outward current was observed at inside positive potentials. The equilibrium potential for this current, although slightly dependent on [K](o), is neither identical with the potassium equilibrium potential nor with the resting potential in normal Tyrode solution.7. Anatomical limitations, primarily resistance in the extracellular space within the bundle, prevent complete characterization of the rapid, large sodium current, but do not limit the application of the clamp method to the study of other, smaller and slower currents. The evidence for this is discussed extensively in the Appendix. PMID:5503866

  15. NATO-3C/Delta launch

    NASA Technical Reports Server (NTRS)

    1978-01-01

    NATO-3C, the third in a series of NATO defense-related communication satellites, is scheduled to be launched on a delta vehicle from the Eastern Test Range no earlier than November 15, 1978. NATO-3A and -3B were successfully launched by Delta vehicles in April 1976 and January 1977, respectively. The NATO-3C spacecraft will be capable of transmitting voice, data, facsimile, and telex messages among military ground stations. The launch vehicle for the NATO-3C mission will be the Delta 2914 configuration. The launch vehicle is to place the spacecraft in a synchronous transfer orbit. The spacecraft Apogee Kick motor is to be fired at fifth transfer orbit apogee to circularize its orbit at geosynchronous altitude of 35,900 km(22,260 miles) above the equator over the Atlantic Ocean somewhere between 45 and 50 degrees W longitude.

  16. Program for the improvement of downhole drilling motors

    SciTech Connect

    Finger, J.T.

    1983-11-01

    This report describes the work done under contract to Sandia National Labs and to the Department of Energy for improvement of downhole drilling motors. The focus of this program was the development of a better bearing-and-seal assembly that could be used in different kinds of drilling motors in a geothermal environment. Major tasks were: (1) design and construction of seal testing devices, (2) screening and evaluation of candidate seals in a simulated bearing/seal package, (3) tests of the most promising candidates in a full-scale bearing/seal package, and (4) analysis of failed seals after testing. The key results from this program were: (1) identification of seal/shaft/lubricant systems that performed well at high pressure and temperature, (2) identification of other seal designs that should be avoided for similar applications, and (3) evaluation of the test machines' design.

  17. Packer cooling system for a downhole steam generator assembly

    SciTech Connect

    Baugh, J.L.; Mooney, F.X.; Vandevier, J.E.

    1989-02-21

    An apparatus is described for providing electrical power to a downhole stream generator in a cased well, comprising in combination: a packer supported on a string of tubing; a connector box; an electrical cable extending from the surface alongside the tubing into the aperture and through the conduit into the connector box; a plurality of electrical conductors extending between the steam generator and engaging a lower end of each electrical connector in the connection plate; and cooling fluid passage means extending through the packer for circulating cooling fluid pumped down from the surface through the packer and back up the well to the surface. The patent also describes a method for installing an operating a steam generator in a well.

  18. Downhole steam generator with improved preheating/cooling features

    SciTech Connect

    Donaldson, A.B.; Hoke, D.E.

    1983-10-25

    An apparatus for down-hole steam generation employs dual-stage preheaters for liquid fuel and for the water. A first heat exchange jacket for the fuel surrounds the fuel/oxidant mixing section of the combustor assembly downstream of the fuel nozzle and contacts the top of the combustor unit of the combustor assembly, thereby receiving heat directly from the combustion of the fuel/ oxidant. A second stage heat exchange jacket surrounds an upper portion of the oxidant supply line adjacent the fuel nozzle, receiving further heat from the compression heat which results from pressurization of the oxidant. The combustor unit includes an inner combustor sleeve, whose inner wall defines the combustion zone. The inner combustor sleeve is surrounded by 2 concentric water channels. The channels are connected by an annular passage adjacent the top of the combustor assembly, and the countercurrent nature of the water flow provides efficient cooling of the inner combustor sleeve. (3 claims.

  19. Comparative evaluation of surface and downhole steam-generation techniques

    NASA Astrophysics Data System (ADS)

    Hart, C.

    The application of heat to reservoirs containing high API gravity oils can substantially improve recovery. Although steam injection is currently the principal thermal recovery method, heat transmission losses associated with delivery of the steam from the surface generators to the oil bearing formation has limited conventional steam injection to shallow reservoirs. The objective of the Department of Energy's Project DEEP STEAM is to develop the technology required to economically produce heavy oil from deep reservoirs. The tasks included in this effort are the development and evaluation of thermally efficient delivery systems and downhole steam generation systems. The technical and economic performance of conventional surface steam drives, which are strongly influenced by heat losses are compared. The selection of a preferred technology based upon either total efficiency or cost is found to be strongly influenced by reservoir depth, steam mass flow rate, and sandface steam quality.

  20. 275 C Downhole Switched-Mode Power Supply

    SciTech Connect

    Chris Hutchens; Vijay Madhuravasal

    2008-08-31

    A vee-square (V2) control based controller IC is developed for a switch mode power supply capable of operating at extreme temperature/harsh environment conditions. A buck type regulator with silicon carbide power junction field effect transistors (JFET) as power devices is used to analyze the performance of controller. Special emphases are made on the analog sub-blocks--voltage reference, operational transconductance amplifier and comparator as individual building blocks. Transformer coupled gate drives and high temperature operable magnetic cores and capacitors are identified and tested for use in the design. Conventional ceramic chip packaging of ICs combined with lead carrier type mounting of passive filter components is introduced for hybrid packaging of the complete product. The developed SMPS is anticipated to support the operation of down-hole microcontrollers and other electronics devices that require low/medium power filtered dc inputs over an operating temperature of 275 C.

  1. Downhole cement test in a very hot hole

    SciTech Connect

    Pettitt, R.A.; Cocks, G.G.; Dreesen, D.N.; Sims, J.R.; Nicholson, R.W.; Boevers, B.

    1982-01-01

    Completion of the commercial-sized Hot Dry Rock Geothermal Energy Project requires that hydraulic fractures be created between two inclined wellbores at a depth of about 4 km (15,000 ft). Isolation of a section of the open wellbore is necessary for pressurization to achieve the fracture connections. A cemented-in liner/PBR assembly is one of the methods used for zone isolation near the botton of the injection well. A downhole, pumped cement test was first conducted at a wellbore temperature of 275/sup 0/C (525/sup 0/F) to determine if a suitable slurry could be designed, pumped, and later recovered to assure the success of the cemented-in liner operation.

  2. Downhole cement test in a very hot hole

    SciTech Connect

    Pettitt, R.A.; Cocks, G.G.; Dreesen, D.S.; Sims, J.R.

    1982-10-01

    Completion of the commercial-sized Hot Dry Rock Geothermal Energy Project requires that hydraulic fractures be created between two inclined wellbores at a depth of about 4 km (15,000 ft). Isolation of a section of the open wellbore is necessary for pressurization to achieve the fracture connections. A cemented-in liner/PBR assembly is one of the methods used for zone isolation near the bottom of the injection well. A downhole, pumped cement test was first conducted at a wellbore temperature of 275/sup 0/C (525/sup 0/F) to determine if a suitable slurry could be designed, pumped, and later recovered to assure the success of the cemented-in liner operation.

  3. Element for use in an inductive coupler for downhole components

    DOEpatents

    Hall, David R.; Fox, Joe

    2009-03-31

    An element for use in an inductive coupler for downhole components comprises an annular housing having a generally circular recess. The element further comprises a plurality of generally linear, magnetically conductive segments. Each segment includes a bottom portion, an inner wall portion, and an outer wall portion. The portions together define a generally linear trough from a first end to a second end of each segment. The segments are arranged adjacent to each other within the housing recess to form a generally circular trough. The ends of at least half of the segments are shaped such that the first end of one of the segments is complementary in form to the second end of an adjacent segment. In one embodiment, all of the ends are angled. Preferably, the first ends are angled with the same angle and the second ends are angled with the complementary angle.

  4. Lithostratigraphy from downhole logs in Hole AND-1B, Antarctica

    USGS Publications Warehouse

    Williams, Trevor; Morin, Roger H.; Jarrard, Richard D.; Jackolski, Chris L.; Henrys, Stuart A.; Niessen, Frank; Magens, Diana; Kuhn, Gerhard; Monien, Donata; Powell, Ross D.

    2012-01-01

    The ANDRILL (Antarctic Drilling Project) McMurdo Ice Shelf (MIS) project drilled 1285 m of sediment in Hole AND–1B, representing the past 12 m.y. of glacial history. Downhole geophysical logs were acquired to a depth of 1018 mbsf (meters below seafloor), and are complementary to data acquired from the core. The natural gamma radiation (NGR) and magnetic susceptibility logs are particularly useful for understanding lithological and paleoenvironmental change at ANDRILL McMurdo Ice Shelf Hole AND–1B. NGR logs cover the entire interval from the seafloor to 1018 mbsf, and magnetic susceptibility and other logs covered the open hole intervals between 692 and 1018 and 237–342 mbsf. In the upper part of AND–1B, clear alternations between low and high NGR values distinguish between diatomite (lacking minerals containing naturally radioactive K, U, and Th) and diamictite (containing K-bearing clays, K-feldspar, mica, and heavy minerals). In the lower open hole logged section, NGR and magnetic susceptibility can also distinguish claystones (rich in K-bearing clay minerals, relatively low in magnetite) and diamictites (relatively high in magnetite). Sandstones can be distinguished by their high resistivity values in AND–1B. On the basis of these three downhole logs, diamictite, claystones, and sandstones can be predicted correctly for 74% of the 692–1018 mbsf interval. The logs were then used to predict facies for the 6% of this interval that was unrecovered by coring. Given the understanding of the physical property characteristics of different facies, it is also possible to identify subtle changes in lithology from the physical properties and help refine parts of the lithostratigraphy, for example, the varying terrigenous content of diatomites and the transitions from subice diamictite to open-water diatomite.

  5. Combination Space Station Handrail Clamp and Pointing Device

    NASA Technical Reports Server (NTRS)

    Hughes, Stephen J. (Inventor)

    1999-01-01

    A device for attaching an experiment carrier to a space station handrail is provided. The device has two major components, a clamping mechanism for attachment to a space station handrail, and a pointing carrier on which an experiment package can be mounted and oriented. The handrail clamp uses an overcenter mechanism and the carrier mechanism uses an adjustable preload ball and socket for carrier positioning. The handrail clamp uses a stack of disk springs to provide a spring loaded button. This configuration provides consistent clamping force over a range of possible handrail thicknesses. Three load points are incorporated in the clamping mechanism thereby spreading the clamping load onto three separate points on the handrail. A four bar linkage is used to provide for a single actuation lever for all three load points. For additional safety, a secondary lock consisting of a capture plate and push lock keeps the clamp attached to the handrail in the event of main clamp failure. For the carrier positioning mechanism, a ball in a spring loaded socket uses friction to provide locking torque; however. the ball and socket are torque limited so that the ball ran slip under kick loads (125 pounds or greater). A lead screw attached to disk spring stacks is used to provide an adjustable spring force on the socket. A locking knob is attached to the lead screw to allow for hand manipulation of the lead screw.

  6. OPTIMAL TIMING FOR CLAMPING THE UMBILICAL CORD AFTER BIRTH

    PubMed Central

    Raju, Tonse N. K.; Singal, Nalini

    2013-01-01

    Synopsis This paper provides a brief overview of pros and cons of clamping the cord too early (within seconds) after birth. It also highlights evolving data that suggests that delaying cord clamping for 30–60 seconds after birth is beneficial to the baby and the mother, with no measurable negative effects. PMID:23164185

  7. 21 CFR 876.5160 - Urological clamp for males.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Urological clamp for males. 876.5160 Section 876.5160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5160 Urological clamp for males. (a) Identification. A urological...

  8. Off-clamp robotic partial nephrectomy: Technique and outcome

    PubMed Central

    Lamoshi, Abdulraouf Y.; Salkini, Mohamad W.

    2015-01-01

    Introduction: Robotic partial nephrectomy (RPN) is a technically challenging procedure. Advanced skills are needed to accomplish tumor resection, hemostasis, and renorrhaphy within short ischemia time in RPN. Off-clamp RPN with zero ischemia may decrease the risk of ischemic reperfusion injury to the kidney. However, the off-clamp technique has been associated with an increased risk of blood loss. The purpose of this study was to evaluate the outcome of our modified off-clamp technique utilized in certain RPN cases. Patients and Methods: A total of 81 patients underwent RPN between September 2009 and July 2013 for renal masses. We studied a subgroup of patients who underwent off-clamp RPN with zero ischemia time. The off-clamp technique was utilized for exophytic, nonhilar tumors that have a base of 2 cm or less. We developed a novel technique to avoid ischemia reperfusion renal injury while minimizing blood loss in certain cases of RPN. Results: Of the 81 cases of RPN, we reviewed and adopted the off-clamp technique in 34 patients (41.98%). Utilizing off-clamp RPN resulted in an average blood loss of 96.29 ml and 1.56 days (range: 1-3 days) of hospital stay and minimal change in serum creatinine. Conclusions: Off-clamp RPN is safe and feasible approach to excise certain kidney tumors. It carries the benefits of RPN and prevents ischemia reperfusion renal injury. PMID:25835489

  9. 21 CFR 876.5160 - Urological clamp for males.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Urological clamp for males. 876.5160 Section 876.5160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5160 Urological clamp for...

  10. 21 CFR 876.5160 - Urological clamp for males.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Urological clamp for males. 876.5160 Section 876.5160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5160 Urological clamp for males. (a) Identification. A urological...

  11. Periodicity Analysis of the Spectral Index in 3c 273 and 3c 446

    NASA Astrophysics Data System (ADS)

    Yuan, Yu-Hai; Fan, Jun-Hui

    In this work, we used the preliminary data of University of Michigan Radio Astronomy Observatory (UMRAO) for the spectral index calculation for two blazars, 3C 273 (1226+023) and 3C 446 (2223-052), and found that the spectral indices are variable. Therefore, we used three methods (Jurkevich method (J), the discrete correlation analysis (D), and the Periodogram method (P)) to investigate the period in the spectral index variation curves. The results show that 3C 273 has a quasi-period of 8.8 ± 1.3 yr, and 3C 446 has a period of 5.8 ± 1.2 yr.

  12. Circumferential hoof clamp method of lameness induction in the horse.

    PubMed

    Swaab, M E; Mendez-Angulo, J L; Groschen, D M; Ernst, N S; Brown, M P; Trumble, T N

    2015-07-01

    A circumferential hoof clamp method to induce controlled and reversible lameness in the forelimbs of eight horses was assessed. Peak vertical forces and vertical impulses were recorded using a force plate to verify induced lameness. Video recordings were used by blinded observers to determine subjective lameness using a 0-5 scale and any residual lameness following clamp loosening. Tightening of clamps resulted in consistent, visible lameness in the selected limbs in all horses. Lameness was confirmed by significant decreases from baseline in the peak vertical force (P <0.01). Lameness was also confirmed subjectively by elevated median scores (0 at baseline and 2 during lameness). Lameness was not immediately reversible after clamp loosening (median score 1.5), but horses were not obviously lame after clamp removal and were no different from initial baseline (median score 0.5) approximately 3 days later. PMID:26045357

  13. Method and apparatus for transmitting and receiving data to and from a downhole tool

    DOEpatents

    Hall, David R.; Fox, Joe

    2007-03-13

    A transmission line network system for transmitting and/or receiving data from a downhole tool. The invention is achieved by providing one or more transceiving elements, preferably rings, at either end of a downhole tool. A conduit containing a coaxial cable capable of communicating an electrical signal is attached to the transceiving element and extends through a central bore of the downhole tool and through the central bore of any tool intermediate the first transceiving element and a second transceiving element. Upon receiving an electrical signal from the cable, the second transceiving element may convert such signal to a magnetic field. The magnetic field may be detected by a third transceiving element in close proximity to the second transceiving element. In this manner, many different tools may be included in a downhole transmission network without requiring substantial modification, if any, of any particular tool.

  14. Report covering examination of parts from downhole steam generators. [Combustor head and sleeve parts

    SciTech Connect

    Pettit, F. S.; Meier, G. H.

    1983-08-01

    Combustor head and sleeve parts were examined by using optical and scanning electron metallography after use in oxygen/diesel and air/diesel downhole steam generators. The degradation of the different alloy components is described in terms of reactions with oxygen, sulfur and carbon in the presence of cyclic stresses, all generated by the combustion process. Recommendations are presented for component materials (alloys and coatings) to extend component lives in the downhole steam generators. 9 references, 22 figures, 3 tables.

  15. Apparatus for downhole drilling communications and method for making and using the same

    DOEpatents

    Normann, R.A.; Lockwood, G.J.; Gonzales, M.

    1998-03-03

    An apparatus for downhole drilling communications is presented. The apparatus includes a spool and end pieces for maintaining the spool at the bottom of a drill string near a drill bit during drilling operations. The apparatus provides a cable for communicating signals between a downhole electronics package and a surface receiver in order to perform measurements while drilling. A method of forming the apparatus is also set forth wherein the apparatus is formed about a central spindle and lathe. 6 figs.

  16. Apparatus for downhole drilling communications and method for making and using the same

    DOEpatents

    Normann, Randy A.; Lockwood, Grant J.; Gonzales, Meliton

    1998-01-01

    An apparatus for downhole drilling communications is presented. The apparatus includes a spool and end pieces for maintaining the spool at the bottom of a drill string near a drill bit during drilling operations. The apparatus provides a cable for communicating signals between a downhole electronics package and a surface receiver in order to perform measurements while drilling. A method of forming the apparatus is also set forth wherein the apparatus is formed about a central spindle and lathe.

  17. Cell-Detection Technique for Automated Patch Clamping

    NASA Technical Reports Server (NTRS)

    McDowell, Mark; Gray, Elizabeth

    2008-01-01

    A unique and customizable machinevision and image-data-processing technique has been developed for use in automated identification of cells that are optimal for patch clamping. [Patch clamping (in which patch electrodes are pressed against cell membranes) is an electrophysiological technique widely applied for the study of ion channels, and of membrane proteins that regulate the flow of ions across the membranes. Patch clamping is used in many biological research fields such as neurobiology, pharmacology, and molecular biology.] While there exist several hardware techniques for automated patch clamping of cells, very few of those techniques incorporate machine vision for locating cells that are ideal subjects for patch clamping. In contrast, the present technique is embodied in a machine-vision algorithm that, in practical application, enables the user to identify good and bad cells for patch clamping in an image captured by a charge-coupled-device (CCD) camera attached to a microscope, within a processing time of one second. Hence, the present technique can save time, thereby increasing efficiency and reducing cost. The present technique involves the utilization of cell-feature metrics to accurately make decisions on the degree to which individual cells are "good" or "bad" candidates for patch clamping. These metrics include position coordinates (x,y) in the image plane, major-axis length, minor-axis length, area, elongation, roundness, smoothness, angle of orientation, and degree of inclusion in the field of view. The present technique does not require any special hardware beyond commercially available, off-the-shelf patch-clamping hardware: A standard patchclamping microscope system with an attached CCD camera, a personal computer with an imagedata- processing board, and some experience in utilizing imagedata- processing software are all that are needed. A cell image is first captured by the microscope CCD camera and image-data-processing board, then the image

  18. The optical variability of 3C 345

    NASA Astrophysics Data System (ADS)

    Kidger, M. R.

    1989-12-01

    The behavior of the light curve of 3C 345 is analyzed using all B magnitudes available in the literature, thus extending the number of points in the compiled light curve of this object by a factor of more than 50 percent and the coverage by about 7 yrs, in comparison with the light curve compiled by Kidger and Beckman (1986). In addition, a new and better m(B) - m(pg) correction is applied to all the data. Results of the analysis demonstrate that the light curve of 3C 345 is effectively aperiodic and that the power spectrum is not continuous, in the sense that even overlapping sections of light curve have very distinct power spectra. This behavior indicates that the curve variations are random. This conclusion is supported by the use of the Jurkevich (1971) V(m)-sq statistic.

  19. Dynamic clamp: a powerful tool in cardiac electrophysiology.

    PubMed

    Wilders, Ronald

    2006-10-15

    Dynamic clamp is a collection of closely related techniques that have been employed in cardiac electrophysiology to provide direct answers to numerous research questions regarding basic cellular mechanisms of action potential formation, action potential transfer and action potential synchronization in health and disease. Building on traditional current clamp, dynamic clamp was initially used to create virtual gap junctions between isolated myocytes. More recent applications include the embedding of a real pacemaking myocyte in a simulated network of atrial or ventricular cells and the insertion of virtual ion channels, either simulated in real time or simultaneously recorded from an expression system, into the membrane of an isolated myocyte. These applications have proven that dynamic clamp, which is characterized by the real-time evaluation and injection of simulated membrane current, is a powerful tool in cardiac electrophysiology. Here, each of the three different experimental configurations used in cardiac electrophysiology is reviewed. Also, directions are given for the implementation of dynamic clamp in the cardiac electrophysiology laboratory. With the growing interest in the application of dynamic clamp in cardiac electrophysiology, it is anticipated that dynamic clamp will also prove to be a powerful tool in basic research on biological pacemakers and in identification of specific ion channels as targets for drug development. PMID:16873403

  20. The Optical Variability of 3C273

    NASA Astrophysics Data System (ADS)

    Lin, Rui-Guang

    2001-06-01

    B-band measurements of 3C273 over some 110 years are compiled and used in a search for periodicities using the Jurkevich method. Periods of 2.0, 13.65±0.20 and 22.5±0.2 yr are found. If the long-term periodicity is from the instability of a slim disk, then the periodicity (~ 13-yr or ~ 22-yr) suggests masses of 107 Msun for the central black holes.

  1. Patch voltage clamp of squid axon membrane.

    PubMed

    Fishman, H M

    1975-12-01

    A small area (patch) of the external surface of a squid axon can be "isolated" electrically from the surrounding bath by means of a pair of concentric glass pipettes. The seawater-filled inner pipette makes contact with the axon and constitutes the external access to the patch. The outer pipette is used to direct flowing sucrose solution over the area surrounding the patch of membrane underlying the inner pipette. Typically, sucrose isolated patches remain in good condition (spike amplitude greater than 90 mV) for periods of approximately one half hour. Patches of axon membrane which had previously been exposed to sucrose solution were often excitable. Membrane survival of sucrose treatment apparently arises from an outflow of ions from the axon and perhaps satellite cells into the interstitial cell space surrounding the exolemma. Estimate of the total access resistance (electrode plus series resistance) to the patch is about 100 komega (7 omega cm2). Patch capacitance ranges from 10-100 pF, which suggests areas of 10(-4) to 10(-5) cm2 and resting patch resistances of 10-100 Momega. Shunt resistance through the interstitial space exposed to sucrose solution, which isolates the patch, is typically 1-2 Momega. These parameters indicate that good potential control and response times can be achieved on a patch. Furthermore, spatial uniformity is demonstrated by measurement of an exoplasmic isopotential during voltage clamp of an axon patch. The method may be useful for other preparations in which limited membrane area is available or in special instances such as in the measurement of membrane conduction noise. PMID:1214276

  2. Downhole Seismic Monitoring in the Istanbul/Eastern Sea of Marmara Region: Recent Results from the ICDP-GONAF Project

    NASA Astrophysics Data System (ADS)

    Bohnhoff, Marco; Dresen, Georg; Acarel, Digdem; Raub, Christina; Kilic, Tugbay; Kartal, Recai; Kadirioglu, Filiz; Nurlu, Murat; Bulut, Fatih; Malin, Peter

    2015-04-01

    As part of the ICDP-GONAF project (Geophysical Observatory at the North Anatolian Fault) geophone arrays are being installed in 300 m deep boreholes around the eastern Sea of Marmara. The objectives of GONAF are to (1) monitor the NAFZ transition from the 1999 Izmit rupture to the Princes Islands offshore Istanbul, where a M ~ 7 earthquake can reasonably be expected to occur and (2) to determine ground-motion amplification and near-surface properties at the GONAF sites. Five geophone arrays are fully operational while two more are being completed in Spring 2015. The vertical arrays consist of one 1 Hz 3C Mark Products L4 seismometer at the surface, three 1 Hz vertical Mark Products L4 seismometers at 75 m depth-spacings, and 1 Hz, 2 Hz and 15 Hz 3C seismometers at 288 m depth. The 1Hz MARK 3C seismometer has been redesigned, gimble-mounted and deployed downhole to operate under low-noise conditions for the first time. During April-May 2013 the GONAF-Tuzla array in eastern Istanbul recorded a microearthquake swarm located ~ 3.5 km epicentral distance east of the site. By cross-correlating the continuous Tuzla data with the only swarm event detected by the regional network (20th of April 2013, Md 1.6) we retrieved an additional of 113 events confirming the expectations of a substantially lowered magnitude-detection threshold allowing for unprecedented fault-zone characterization along the Princes island fault segment offshore of Istanbul.

  3. Inductive coupler for downhole components and method for making same

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Briscoe, Michael A.; Sneddon, Cameron; Fox, Joe

    2006-05-09

    The present invention includes a method of making an inductive coupler for downhole components. The method includes providing an annular housing, preferably made of steel, the housing having a recess. A conductor, preferably an insulated wire, is also provided along with a plurality of generally U-shaped magnetically conducting, electrically insulating (MCEI) segments. Preferably, the MCEI segments comprise ferrite. An assembly is formed by placing the plurality of MCEI segments within the recess in the annular housing. The segments are aligned to form a generally circular trough. A first portion of the conductor is placed within the circular trough. This assembly is consolidated with a meltable polymer which fills spaces between the segments, annular housing and the first portion of the conductor. The invention also includes an inductive coupler including an annular housing having a recess defined by a bottom portion and two opposing side wall portions. At least one side wall portion includes a lip extending toward but not reaching the other side wall portion. A plurality of generally U-shaped MCEI segments, preferably comprised of ferrite, are disposed in the recess and aligned so as to form a circular trough. The coupler further includes a conductor disposed within the circular trough and a polymer filling spaces between the segments, the annular housing and the conductor.

  4. Enhanced oil recovery using direct downhole steam generation

    SciTech Connect

    Fox, R.L.

    1983-01-01

    High pressure, direct contact steam generators are capable of producing high quality steam and inert combustion gas from a compact apparatus. The combination of steam and inert gas is attractive for many enhanced recovery operations. Direct contact steam generators can be utilized to produce steam with gases either on the surface or down hole. The utilization of these devices down hole can reduce capital and operating costs and eliminate delivery heat loss at the expense of a loss of accessibility. These devices are usually referred to as down-hole generators, even if operated on the surface. The current state of technology of these generators has evolved from a series of field test demonstrations to commercial deployment. The results obtained from demonstration tests conducted in reservoirs ranging from 250 to 800 m in depth showed that these devices could be operated successfully in the oil field for long periods of time. Subsequent to the successful demonstrations, commercial equipment has been deployed in various reservoir conditions. The results from both demonstration tests and current commercial operations are discussed.

  5. Downhole steam generator with improved preheating/cooling features

    DOEpatents

    Donaldson, A. Burl; Hoke, Donald E.; Mulac, Anthony J.

    1983-01-01

    An apparatus for downhole steam generation employing dual-stage preheaters for liquid fuel and for the water. A first heat exchange jacket for the fuel surrounds the fuel/oxidant mixing section of the combustor assembly downstream of the fuel nozzle and contacts the top of the combustor unit of the combustor assembly, thereby receiving heat directly from the combustion of the fuel/oxidant. A second stage heat exchange jacket surrounds an upper portion of the oxidant supply line adjacent the fuel nozzle receiving further heat from the compression heat which results from pressurization of the oxidant. The combustor unit includes an inner combustor sleeve whose inner wall defines the combustion zone. The inner combustor sleeve is surrounded by two concentric water channels, one defined by the space between the inner combustor sleeve and an intermediate sleeve, and the second defined by the space between the intermediate sleeve and an outer cylindrical housing. The channels are connected by an annular passage adjacent the top of the combustor assembly and the countercurrent nature of the water flow provides efficient cooling of the inner combustor sleeve. An annular water ejector with a plurality of nozzles is provided to direct water downwardly into the combustor unit at the boundary of the combustion zone and along the lower section of the intermediate sleeve.

  6. Development of technology for downhole steam production. SPE Paper 9776

    SciTech Connect

    Fox, R. L.; Donaldson, A. B.; Mulac, A. J.

    1981-01-01

    Two concepts for downhole production of steam for drive operations have been selected for comparative development. The two designs differ in method of transferring heat from hot combustion gases to produce steam. A low pressure combustion design transfers energy to water through a heat exchanger thus enabling the combustion process to be conducted at a pressure less than the injection pressure; a high pressure combustion design mixes the combustion gases directly with water, resulting in the injection of steam and combustion gases into the reservoir. The comparative development program has included analysis of energy efficiency, computational examination of recovery, core recovery experiments, and field evaluation. Field tests have been conducted under low reservoir injection pressure (2.76 MPa). The tests were carried out in a 260 m (800 ft) deep reservoir utilizing a 2.5 acre five spot pattern. Data collected from injection and production wells included fluid flow rates, fluid compositions, and energy content. The reservoir conditions were monitored by a combination of global flow measurements and simultaneous core flow tests. Test results have demonstrated that the recovery with the high pressure combustion design is equivalent to the low pressure design at low reservoir pressure. The injection of combustion gases with steam have reduced the quantity of air contaminents released to the atmosphere.

  7. Inference of dynamic shear modulus from Lotung downhole data

    SciTech Connect

    Chang, C.Y.; Mok, C.M.; Tang, H.T.

    1996-08-01

    Downhole ground motions recorded at the Lotung Large-Scale Seismic Test (LSST) site were used in this paper to infer in-situ dynamic soil properties. The purposes were (1) to provide field evidence of nonlinear soil behavior during earthquake excitation; and (2) to evaluate the accuracy of dynamic properties obtained from geophysical measurements and laboratory tests. For each horizontal component and event analyzed, representative shear-wave velocity and effective shear strain (defined as 65% of peak strain) between consecutive recording stations were estimated. The representative shear-wave velocities were estimated from fundamental resonant frequencies identifiable from the Fourier spectral ratios. The effective shear strains were estimated by linear ground response deconvolution analyses based on the inferred shear-wave velocity profiles. The inferred reduction in shear modulus with increasing effective shear strain was compared with laboratory test data. The degree of agreement between the inferred shear modulus reduction curves and the laboratory test data varied with different testing programs. The inferred low-strain shear-wave velocity profile agreed with geophysical measurements. These observations not only provide field evidence of nonlinear dynamic soil behavior during earthquakes, but also confirm the reasonableness of data provided by geophysical measurements and laboratory tests.

  8. Drilling Optimization Utilizing Surface Instrumentaton for Downhole Event Recognition

    SciTech Connect

    John H. Cohen; Greg Deskins

    2006-02-01

    This DOE project was undertaken to develop and test an instrumented data-acquisition sub that is mounted in a drill string below the top drive and used to detect downhole events. Data recorded at the surface during drilling operations would then be processed and presented to the driller to discern undesirable drilling conditions and help optimize drilling rates and maximize the life of components in the BHA. This instrumented sub was originally conceived and developed solely as a single-point collection center for rig data that would be used in a number of Noble's products. The sub was designed to collect hook load, rotary torque, rotary speed, rotary position, drill pipe pressure, mud temperature, triaxial vibration, and triaxial magnetometer data. The original design and fabrication was by Sandia National Labs under Noble's direction, which was then tested with Sandia's diagnostics-while-drilling downhole package. After initial results were analyzed, the team surmised that important information describing performance and condition of the bottom-hole assembly (BHA) was embedded in the data recorded by the instrumented sub, and began investigating the potential of using surface measurements from the sub to highlight problems occurring downhole before they could be discerned by the driller. Later, a proposal was submitted to DOE for funding to more broadly investigate use of the system for detecting downhole problems while drilling. Soon after DOE awarded this contract, the Noble team responsible for the previous developments was disbanded and their work terminated (due to factors unrelated to the sub development). This change halted the complementary work that Noble had planned to conduct during the DOE project, and necessitated that all the development work be completed by the DOE project. More effort was expended on the project to develop a field-ready prototype than was originally foreseen. The sub's design had to be significantly modified during the project

  9. Advances in downhole sampling of high temperature solutions

    SciTech Connect

    Bayhurst, G.K.; Janecky, D.R.

    1991-01-01

    A fluid sampler capable of sampling hot and/or deep wells has been developed at Los Alamos National Laboratory. In collaboration with Leutert Instruments, an off-the-shelf sampler design was modified to meet gas-tight and minimal chemical reactivity/contamination specifications for use in geothermal wells and deep ocean drillholes. This downhole sampler has been routinely used at temperatures up to 300{degrees}C and hole depths of greater than 5 km. We have tested this sampler in various continental wells, including Valles Caldera VC-2a and VC-2b, German KTB, Cajon Pass, and Yellowstone Y-10. Both the standard commercial and enhanced samplers have also been used to obtain samples from a range of depths in the Ocean Drilling Project's hole 504B and during recent mid-ocean ridge drilling efforts. The sampler has made it possible to collect samples at temperatures and conditions beyond the limits of other tools with the added advantage of chemical corrosion resistance.

  10. Examples of individual downhole heat exchangers systems in Klamath Falls

    SciTech Connect

    Lund, J.W.

    1999-09-01

    The downhole heat exchanger (DHE), used extensively in Klamath Falls in over 500 installations, provides heating for one or more homes from a single geothermal well. The DHE eliminates the problem of disposal for geothermal fluids, since only heat is taken from the well. The heat exchangers consists of a loop of pipe or tubes (locally called a coil) suspended in the geothermal well through which clean secondary city water is pumped or allowed to circulate by natural convection. These systems offer substantial economic savings over surface heat exchangers where a single-well system is adequate. The maximum output of large installations is typically less than 2.73 {times} 10{sup 6} Btu/hr or 0.8 MWt, with well depths up to about 500 feet, and may be economical under certain conditions at well depths of 1500 feet. However, typical DHE output for individual homes tends to be less than 250,000 Btu/hr or 0.07 MWt. The paper describes a basic installation and a complex installation.

  11. Insulin Tolerance Test and Hyperinsulinemic-Euglycemic Clamp

    PubMed Central

    Paschos, Georgios K.; FitzGerald, Garret A.

    2016-01-01

    The two tests are used to evaluate in vivo sensitivity to insulin in mouse. The hypoerinsulinemic-euglycemic clamp provides information about the sensitivity to insulin in liver and other metabolically relevant tissues.

  12. A clamp-like biohybrid catalyst for DNA oxidation

    NASA Astrophysics Data System (ADS)

    van Dongen, Stijn F. M.; Clerx, Joost; Nørgaard, Kasper; Bloemberg, Tom G.; Cornelissen, Jeroen J. L. M.; Trakselis, Michael A.; Nelson, Scott W.; Benkovic, Stephen J.; Rowan, Alan E.; Nolte, Roeland J. M.

    2013-11-01

    In processive catalysis, a catalyst binds to a substrate and remains bound as it performs several consecutive reactions, as exemplified by DNA polymerases. Processivity is essential in nature and is often mediated by a clamp-like structure that physically tethers the catalyst to its (polymeric) template. In the case of the bacteriophage T4 replisome, a dedicated clamp protein acts as a processivity mediator by encircling DNA and subsequently recruiting its polymerase. Here we use this DNA-binding protein to construct a biohybrid catalyst. Conjugation of the clamp protein to a chemical catalyst with sequence-specific oxidation behaviour formed a catalytic clamp that can be loaded onto a DNA plasmid. The catalytic activity of the biohybrid catalyst was visualized using a procedure based on an atomic force microscopy method that detects and spatially locates oxidized sites in DNA. Varying the experimental conditions enabled switching between processive and distributive catalysis and influencing the sliding direction of this rotaxane-like catalyst.

  13. The peculiar radio galaxy 3C 433

    NASA Technical Reports Server (NTRS)

    Van Breugel, W.; Helfand, D.; Balick, B.; Heckman, T.; Miley, G.

    1983-01-01

    Radio, optical and X-ray observations are presented of the peculiar radio galaxy 3C 433, a Seyfert 2 object with luminosity an order of magnitude greater than that expected from its complex, shell-type morphology. Observations conducted at 6 and 12 cm with the VLA and at 21 cm with the Westerbork telescope show a striking asymmetry between the northern and southern radio emissions, and an overall X-shaped morphology. Optical observations using the Video Camera and High Gain Video Spectrometer on the 4-m telescope and the Intensified Image Dissector Scanner on the 2.1-m telescope at Kitt Peak confirm the identification of the source with a pair of bright galaxies. Observations in the X-ray from the Einstein Observatory IPC reveal an unresolved source at the position of 3C 433, as well as two serendipitous X-ray sources. The observations may be used to explain the overall structure of the source either in terms of tidal torquing or precessing models of double galaxies; however, it is argued that the tidal torquing model requires fewer assumptions to account for the brightness asymmetry.

  14. Downhole geophysical observatories: best installation practices and a case history from Turkey

    NASA Astrophysics Data System (ADS)

    Prevedel, Bernhard; Bulut, Fatih; Bohnhoff, Marco; Raub, Christina; Kartal, Recai F.; Alver, Fatih; Malin, Peter E.

    2015-09-01

    Downhole sensors of different types and in various environments provide substantial benefit to signal quality. They also add the depth dimension to measurements performed at the Earths' surface. Sensor types that particularly benefit from downhole installation due to the absence of near-surface noise include piezometers, seismometers, strainmeters, thermometers, and tiltmeters. Likewise, geochemical and environmental measurements in a borehole help eliminate near-surface weathering and cultural effects. Installations from a few hundred meter deep to a few kilometer deep dramatically reduce surface noise levels—the latter noticeably also reduces the hypocentral distance for shallow microearthquakes. The laying out of a borehole network is always a compromise of local boundary conditions and the involved drilling costs. The installation depth and procedure for a long-term downhole observatory can range from time limited installations, with a retrieval option, to permanently cemented sensors. Permanently cemented sensors have proven to be long-term stable with non-deteriorating coupling and borehole integrity. However, each type needs to be carefully selected and planned according to the research aims. A convenient case study is provided by a new installation of downhole seismometers along the shoreline of the eastern Marmara Sea in Turkey. These stations are being integrated into the regional net for monitoring the North Anatolian Fault Zone. Here we discuss its design, installation, and first results. We conclude that, despite the logistical challenges and installation costs, the superior quality of downhole data puts this technique at the forefront of applied and fundamental research.

  15. Two Active Nuclei in 3C 294

    NASA Astrophysics Data System (ADS)

    Stockton, Alan; Canalizo, Gabriela; Nelan, E. P.; Ridgway, Susan E.

    2004-01-01

    The z=1.786 radio galaxy 3C 294 lies < 10" from a 12 mag star and has been the target of at least three previous investigations using adaptive optics (AO) imaging. A major problem in interpreting these results is the uncertainty in the precise alignment of the radio structure with the H- or K-band AO imaging. Here we report observations of the position of the AO guide star with the Hubble Space Telescope Fine Guidance Sensor, which, together with positions from the second United States Naval Observatory's CCD Astrograph Catalog (UCAC2), allow us to register the infrared and radio frames to an accuracy of better than 0.1". The result is that the nuclear compact radio source is not coincident with the brightest discrete object in the AO image, an essentially unresolved source on the eastern side of the light distribution, as Quirrenbach and coworkers had suggested. Instead, the radio source is centered about 0.9" to the west of this object, on one of the two apparently real peaks in a region of diffuse emission. Nevertheless, the conclusion of Quirrenbach and coworkers that 3C 294 involves an ongoing merger appears to be correct: analysis of a recent deep Chandra image of 3C 294 obtained from the archive shows that the nucleus comprises two X-ray sources, which are coincident with the radio nucleus and the eastern stellar object. The X-ray/optical flux ratio of the latter makes it extremely unlikely that it is a foreground Galactic star. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555. These observations are associated with proposal 08315. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a

  16. Feasibility evaluation of downhole oil/water separator (DOWS) technology.

    SciTech Connect

    Veil, J. A.; Langhus, B. G.; Belieu, S.

    1999-01-31

    The largest volume waste stream associated with oil and gas production is produced water. A survey conducted by the American Petroleum Institute estimated that 20.9 billion barrels of produced water were disposed of in 1985 (Wakim 1987). Of this total, 91% was disposed of through disposal wells or was injected for enhanced oil recovery projects. Treatment and disposal of produced water represents a significant cost for operators. A relatively new technology, downhole oil/water separators (DOWS), has been developed to reduce the cost of handling produced water. DOWS separate oil and gas from produced water at the bottom of the well and reinject some of the produced water into another formation or another horizon within the same formation, while the oil and gas are pumped to the surface. Since much of the produced water is not pumped to the surface, treated, and pumped from the surface back into a deep formation, the cost of handling produced water is greatly reduced. When DOWS are used, additional oil may be recovered as well. In cases where surface processing or disposal capacity is a limiting factor for further production within a field, the use of DOWS to dispose of some of the produced water can allow additional production within that field. Simultaneous injection using DOWS minimizes the opportunity for contamination of underground sources of drinking water (USDWs) through leaks in tubing and casing during the injection process. This report uses the acronym 'DOWS' although the technology may also be referred to as DHOWS or as dual injection and lifting systems (DIALS). Simultaneous injection using DOWS has the potential to profoundly influence the domestic oil industry. The technology has been shown to work in limited oil field applications in the United States and Canada. Several technical papers describing DOWS have been presented at oil and gas industry conferences, but for the most part, the information on the DOWS technology has not been widely transferred

  17. Double Faraday rotation toward 3C 27

    NASA Astrophysics Data System (ADS)

    Goldstein, S. J., Jr.; Reed, J. A.

    1984-08-01

    From observations of the integrated flux of 3C 27 with the NRAO 140 foot (43 m) telescope at 40 frequencies between 1250 and 1445 MHz, the authors deduce rotation measures of 165±15 and -104±4 rad m-2. Since the source (assumed to be a radio galaxy) has components 45arcsec apart, it is concluded that the net magnetic field reverses between these directions. One explanation is that a large magnetic field surrounding the central galaxy of the distant source covers one component but not the other. Another explanation is that our Galaxy contains a dipole field with a scale of order 1 pc. One component of the distant source is seen inside the current loop associated with the dipole field, while the other is seen outside the loop.

  18. Downhole fluid analysis and asphaltene science for petroleum reservoir evaluation.

    PubMed

    Mullins, Oliver C; Pomerantz, Andrew E; Zuo, Julian Y; Dong, Chengli

    2014-01-01

    Petroleum reservoirs are enshrouded in mysteries associated with all manner of geologic and fluid complexities that Mother Nature can inspire. Efficient exploitation of petroleum reservoirs mandates elucidation of these complexities; downhole fluid analysis (DFA) has proven to be indispensable for understanding both fluids and reservoir architecture. Crude oil consists of dissolved gases, liquids, and dissolved solids, known as the asphaltenes. These different fluid components exhibit fluid gradients vertically and laterally, which are best revealed by DFA, with its excellent precision and accuracy. Compositional gradient analysis falls within the purview of thermodynamics. Gas-liquid equilibria can be treated with a cubic equation of state (EoS), such as the Peng-Robinson EoS, a modified van der Waals EoS. In contrast, the first EoS for asphaltene gradients, the Flory-Huggins-Zuo (FHZ) EoS, was developed only recently. The resolution of the asphaltene molecular and nanocolloidal species in crude oil, which is codified in the Yen-Mullins model of asphaltenes, enabled the development of this EoS. The combination of DFA characterization of gradients of reservoir crude oil with the cubic EoS and FHZ EoS analyses brings into view wide-ranging reservoir concerns, such as reservoir connectivity, fault-block migration, heavy oil gradients, tar mat formation, huge disequilibrium fluid gradients, and even stochastic variations of reservoir fluids. New petroleum science and DFA technology are helping to offset the increasing costs and technical difficulties of exploiting ever-more-remote petroleum reservoirs. PMID:24702298

  19. Spectral infrared hemispherical reflectance measurements for LDEF tray clamps

    NASA Technical Reports Server (NTRS)

    Wood, Bobby E.; Cromwell, Brian K.; Pender, Charles W.; Shepherd, Seth D.

    1992-01-01

    This paper describes infrared hemispherical reflectance measurements (2-15 microns) that were made on 58 chromic acid anodized tray clamps retrieved from the LDEF spacecraft. These clamps were used for maintaining the experiments in place and were located at various locations about the spacecraft. Changes in reflectance of the tray clamps at these locations were compared with atomic oxygen fluxes at the same locations. A decrease in absorption band depth was seen for the surfaces exposed to space indicating that there was some surface layer erosion. In all of the surfaces measured, little evidence of contamination was observed and none of the samples showed evidence of the brown nicotine stain that was so prominent in other experiments. Total emissivity values were calculated for both exposed and unexposed tray clamp surfaces. Only small differences, usually less than 1 percent, were observed. The spectral reflectances were measured using a hemi-ellipsoidal mirror reflectometer matched with an interferometer spectrometer. The rapid scanning capability of the interferometer allowed the reflectance measurements to be made in a timely fashion. The ellipsoidal mirror has its two foci separated by 2 inches and located on the major axis. A blackbody source was located at one focus while the tray clamp samples were located at the conjugate focus. The blackbody radiation was modulated and then focused by the ellipsoid onto the tray clamps. Radiation reflected from the tray clamp was sampled by the interferometer by viewing through a hole in the ellipsoid. A gold mirror (reflectance approximately 98 percent) was used as the reference surface.

  20. Measuring beta-cell function relative to insulin sensitivity in youth: Does the hyperglycemic clamp suffice?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To compare beta-cell function relative to insulin sensitivity, disposition index (DI), calculated from two clamps (2cDI, insulin sensitivity from the hyperinsulinemic-euglycemic clamp and first-phase insulin from the hyperglycemic clamp) with the DI calculated from the hyperglycemic clamp alone (hcD...

  1. Development of an improved bearing pack for downhole motors in geothermal applications

    SciTech Connect

    DeLafosse, P.H.; Black, A.D.; Sandstrom, J.L.; Tibbitts, G.A.

    1981-10-01

    A sealed bearing pack (called the Bearing-Seal Package) is being developed for use with downhole mud motors and turbines for geothermal applications. The Bearing-Seal Package contains a sealed lubrication system which allows the bearings to operate in oil instead of abrasive drilling mud. The key to the success of the lubrication system is the development of a reliable rotary seal that will operate under downhole conditions. The development program emphasizes extensive laboratory screening tests of candidate high temperature seals and lubricants. A Seal Test Machine has been constructed to test candidate high temperature seals under simulated downhole conditions. Descriptions of the Bearing-Seal Package and Seal Test Machine are presented. Candidate high temperature seals and lubricants are reviewed and seal tests are discussed.

  2. Apparatus and method for compensating for clock drift in downhole drilling components

    DOEpatents

    Hall, David R.; Pixton, David S.; Johnson, Monte L.; Bartholomew, David B.; Hall, Jr., H. Tracy

    2007-08-07

    A precise downhole clock that compensates for drift includes a prescaler configured to receive electrical pulses from an oscillator. The prescaler is configured to output a series of clock pulses. The prescaler outputs each clock pulse after counting a preloaded number of electrical pulses from the oscillator. The prescaler is operably connected to a compensator module for adjusting the number loaded into the prescaler. By adjusting the number that is loaded into the prescaler, the timing may be advanced or retarded to more accurately synchronize the clock pulses with a reference time source. The compensator module is controlled by a counter-based trigger module configured to trigger the compensator module to load a value into the prescaler. Finally, a time-base logic module is configured to calculate the drift of the downhole clock by comparing the time of the downhole clock with a reference time source.

  3. Multiwavelength observations of giant radio galaxy 3C 35 and 3C 284

    NASA Astrophysics Data System (ADS)

    Pal, Sabyasachi; Chakrabarti, Sandip Kumar; Patra, Dusmanta; Konar, Chiranjib

    2016-07-01

    We report multi wavelength observations of large radio galaxy 3C35 and 3C284. The low frequency observations were done with the Giant Metrewave Radio Telescope (GMRT) starting from 150 MHz. The high frequency observations were done with Jansky Very Large Array (JVLA). Our main motivation for these observations is to estimate the spectral ages of these galaxies and to examine any proof of extended emission at low radio frequencies due to an earlier cycle of activity. The spectral age is measured by fitting the spectra with different spectral ageing models e.g. Kardashev-Pacholczyk (KP), Jaffe-Perola (JP) and Continuous Injection (CI).

  4. Development of a High Pressure/High Temperature Down-hole Turbine Generator

    SciTech Connect

    Ben Plamp

    2008-06-30

    As oil & natural gas deposits become more difficult to obtain by conventional means, wells must extend to deeper more heat-intensive environments. The technology of the drilling equipment required to reach these depths has exceeded the availability of electrical power sources needed to operate these tools. Historically, logging while drilling (LWD) and measure while drilling (MWD) devices utilized a wireline to supply power and communication from the operator to the tool. Lithium ion batteries were used in scenarios where a wireline was not an option, as it complicated operations. In current downhole applications, lithium ion battery (LIB) packs are the primary source for electrical power. LIB technology has been proven to supply reliable downhole power at temperatures up to 175 °C. Many of the deeper well s reach ambient temperatures above 200 °C, creating an environment too harsh for current LIB technology. Other downfalls of LIB technology are cost, limitations on charge cycles, disposal issues and possible safety hazards including explosions and fires. Downhole power generation can also be achieved by utilizing drilling fluid flow and converting it to rotational motion. This rotational motion can be harnessed to spin magnets around a series of windings to produce power proportional to the rpm experienced by the driven assembly. These generators are, in most instances, driven by turbine blades or moyno-based drilling fluid pumps. To date, no commercially available downhole power generators are capable of operating at ambient temperatures of 250 °C. A downhole power g enerator capable of operation in a 250 °C and 20,000 psi ambient environment will be an absolute necessity in the future. Dexter Magnetic Technologies’ High-Pressure High-Temperature (HPHT) Downhole Turbine Generator is capable of operating at 250 °C and 20, 000 psi, but has not been tested in an actual drilling application. The technology exists, but to date no company has been willing to

  5. Dynamic Clamp in Cardiac and Neuronal Systems Using RTXI

    PubMed Central

    Ortega, Francis A.; Butera, Robert J.; Christini, David J.; White, John A.; Dorval, Alan D.

    2016-01-01

    The injection of computer-simulated conductances through the dynamic clamp technique has allowed researchers to probe the intercellular and intracellular dynamics of cardiac and neuronal systems with great precision. By coupling computational models to biological systems, dynamic clamp has become a proven tool in electrophysiology with many applications, such as generating hybrid networks in neurons or simulating channelopathies in cardiomyocytes. While its applications are broad, the approach is straightforward: synthesizing traditional patch clamp, computational modeling, and closed-loop feedback control to simulate a cellular conductance. Here, we present two example applications: artificial blocking of the inward rectifier potassium current in a cardiomyocyte and coupling of a biological neuron to a virtual neuron through a virtual synapse. The design and implementation of the necessary software to administer these dynamic clamp experiments can be difficult. In this chapter, we provide an overview of designing and implementing a dynamic clamp experiment using the Real-Time eXperiment Interface (RTXI), an open- source software system tailored for real-time biological experiments. We present two ways to achieve this using RTXI’s modular format, through the creation of a custom user-made module and through existing modules found in RTXI’s online library. PMID:25023319

  6. THE SUZAKU VIEW OF 3C 382

    SciTech Connect

    Sambruna, R. M.; Gliozzi, M.; Tombesi, F.; Braito, V.; Ballo, L.; Reynolds, C. S.

    2011-06-20

    We present a long (116 ks) Suzaku observation of the broad-line radio galaxy (BLRG) 3C 382 acquired in 2007 April. A Swift BAT spectrum in 15-200 keV from the 58 month survey is also analyzed, together with an archival XMM-Newton EPIC exposure of 20 ks obtained one year after Suzaku. Our main result is the finding with Suzaku of a broad Fe K line with a relativistic profile consistent with emission from an accretion disk at tens of gravitational radii from the central black hole. The XIS data indicate emission from highly ionized iron and allow us to set tight, albeit model-dependent, constraints on the inner and outer radii of the disk reflecting region, r{sub in} {approx_equal} 10 r{sub g} and r{sub out} {approx_equal} 20 r{sub g} , respectively, and on the disk inclination, i {approx_equal} 30{sup 0}. Two ionized reflection components are possibly observed, with similar contributions of {approx}10% to the total continuum-a highly ionized one, with log{xi} {approx_equal} 3 erg s{sup -1} cm, which successfully models the relativistic line, and a mildly ionized one, with log{xi} {approx_equal} 1.5 erg s{sup -1} cm, which models the narrow Fe K{alpha} and high energy hump. When both these components are included, there is no further requirement for an additional blackbody soft excess below 2 keV. The Suzaku data confirm the presence of a warm absorber previously known from grating studies. After accounting for all the spectral features, the intrinsic photon index of the X-ray continuum is {Gamma}{sub x} {approx_equal} 1.8 with a cutoff energy at {approx}200 keV, consistent with Comptonization models and excluding jet-related emission up to these energies. Comparison of the X-ray properties of 3C 382 and other BLRGs to Seyferts recently observed with Suzaku and BAT confirms the idea that the distinction between radio-loud and radio-quiet active galactic nucleus at X-rays is blurred. The two classes form a continuum distribution in terms of X-ray photon index

  7. Summary of DEEP STEAM downhole steam generator development activities. [Kern River and Long Beach field tests

    SciTech Connect

    Donaldson, A.B.; Fox, R.L.; Mulac, A.J.

    1981-01-01

    In this paper the concept and goals of the DOE program, DEEP STEAM, as related to the development of a downhole steam generator for deep heavy oil recovery will be discussed. Additionally, the past, present and future activities of the development program being carried out at Sandia National Laboratories will be discussed. These include evaluation studies, surface testing at Bakersfield, CA, a run-in test at Hobbs, NM, and status of field testing at Long Beach, CA. The Long Beach test includes both a downhole diesel-air generator and a surface diesel-oxygen generator. 7 figures.

  8. Multifrequency Monitoring of 3C 120, 3C 279, and PKS 1510--089

    NASA Technical Reports Server (NTRS)

    Jorstad, S. G.; Marscher, A. P.; Aller, M. F.; Balonek, T. J.; Gomez, J.-L.; McHardy, I. M.; Terasranta, H.; Raiteri, C.; Tosti, G.

    2001-01-01

    We analyze contemporaneous X-ray, optical, and radio light curves of 3C 120, ABC 279, and PKS 1510-089 on timescales from a few to hundreds of days over a 3-5 year period. The results show the diverse connections between variability properties at different frequencies for different blazers.

  9. The resolved outflow from 3C 48

    SciTech Connect

    Shih, Hsin-Yi; Stockton, Alan E-mail: stockton@ifa.hawaii.edu

    2014-10-20

    We investigate the properties of the high-velocity outflow driven by the young radio jet of 3C 48, a compact-steep-spectrum source. We use the Space Telescope Imaging Spectrograph on board the Hubble Space Telecope to obtain (1) low-resolution UV and optical spectra and (2) multi-slit medium-resolution spectra of the ionized outflow. With supporting data from ground-based spectrographs, we are able to accurately measure the ratios of diagnostic emission lines such as [O III] λ5007, [O III] λ3727, [N II] λ6548, Hα, Hβ, [Ne V] λ3425, and [Ne III] λ3869. We fit the observed emission-line ratios using a range of ionization models, powered by active galactic nucleus (AGN) radiation and shocks, produced by the MAPPINGS code. We have determined that AGN radiation is likely the dominant ionization source. The outflow's density is estimated to be in the range n = 10{sup 3}-10{sup 4} cm{sup –3}, the mass is ∼6 × 10{sup 6} M {sub ☉}, and the metallicity is likely equal to or higher than solar. Compared with the typical outflows associated with more evolved radio jets, this young outflow is denser, less massive, and more metal rich. Multi-slit observations allow us to construct a two-dimensional velocity map of the outflow that shows a wide range of velocities with distinct velocity components, suggesting a wide-angle clumpy outflow.

  10. Self-locking clamping tool with swivel jaws

    NASA Technical Reports Server (NTRS)

    Redmon, Jr., John W. (Inventor); Jankowski, Fred (Inventor)

    1989-01-01

    A plier-like tool (11) having two plier-like members (13, 15) pivotally joined togther intermediate of their ends and having handle portions (17, 18) and swivel jaw members (29,30). An automatic locking mechanism (27) extending between the members permits an user to clamp the handle portions together so as to clamp the jaw members on an object (25) but holds the position so reached if the clamping action of the user is removed. A release device (65) is provided so that the jaw members may be opened up again. A compression spring (23) extending between the members (19, 20) assists in the opening of the jaw members. The swivel jaw members (29, 30) permit the user to rotate the plier-like members (13,15) relative to the object (25) being grasped.

  11. Hysteresis modeling of clamp band joint with macro-slip

    NASA Astrophysics Data System (ADS)

    Qin, Zhaoye; Cui, Delin; Yan, Shaoze; Chu, Fulei

    2016-01-01

    Clamp band joints are commonly used to connect spacecrafts with launch vehicles. Due to the frictional slippage between the joint components, hysteresis behavior might occur at joint interfaces under cyclic loading. The joint hysteresis will bring friction damping into the launching systems. In this paper, a closed-form hysteresis model for the clamp band joint is developed based on theoretical and numerical analyses of the interactions of the joint components. Then, the hysteresis model is applied to investigating the dynamic response of a payload fastened by the clamp band joint, where the nonlinearity and friction damping effects of the joint is evaluated. The proposed analytical model, which is validated by both finite element analyses and quasi-static experiments, has a simple form with sound accuracy and can be incorporated into the dynamic models of launching systems conveniently.

  12. [Pedicular clamping in major hepatectomies: clamping "of principle" or "of necessity"? A comparative study].

    PubMed

    Le Treut, Y P; Christophe, M; Banti, J C; Berthet, B; Bricot, R

    1995-02-01

    Fifty-two consecutive patients undergoing major hepatic resection for liver tumor were divided into two groups according to the operative procedure. Group A consisted of 34 patients in whom vascular inflow occlusion was performed "de principle" during parenchymal division and intrahepatic approach of the portal structures; the mean duration of the portal triad clamping was 43 mn (ranged 17 to 70 mn). Group B patients (18 cases) had hilar division of the structures of that portion of the liver due to be removed, prior to parenchymal division was performed without vascular arrest, except in five "de necessitate" cases during 5 to 22 mn. Groups A and B were comparable in terms of patient age or status, of king of liver tumors and extent of resection. Mean operating duration (215 vs 263 mn), volume of intraoperative blood transfusion (557 vs 1019 ml), intensive care (2.5 vs 4.2 days) and total hospital stays (19.6 vs 30.5 days) were significantly reduced in group A. A higher but transient increase of amino-transferase level was the only biochemical consequence of liver ischemia in group A, whereas postoperative disturbance in serum bilirubin, prothrombin time, fibrinogen, and total protein were significantly greater in group B, probably because of the greater volume of blood transfusion in this group. Thus, routine vascular inflow occlusion with transhepatic approach of the portal structures may be an effective and innocuous procedure for major liver resection. PMID:7751341

  13. Plasma temperature clamping in filamentation laser induced breakdown spectroscopy

    SciTech Connect

    Harilal, Sivanandan S.; Yeak, J.; Phillips, Mark C.

    2015-10-19

    Ultrafast laser filament induced breakdown spectroscopy is a very promising method for remote material detection. We present characteristics of plasmas generated in a metal target by laser filaments in air. Our measurements show that the temperature of the ablation plasma is clamped along the filamentation channel due to intensity clamping in a filament. Nevertheless, significant changes in radiation intensity are noticeable, and this is essentially due to variation in the number density of emitting atoms. The present results also partly explains the reason for the occurrence of atomic plume during fs LIBS in air compared to long-pulse ns LIBS.

  14. Plasma temperature clamping in filamentation laser induced breakdown spectroscopy.

    PubMed

    Harilal, S S; Yeak, J; Phillips, M C

    2015-10-19

    Ultrafast laser filament induced breakdown spectroscopy is a very promising method for remote material detection. We present characteristics of plasmas generated in a metal target by laser filaments in air. Our measurements show that the temperature of the ablation plasma is clamped along the filament channel due to intensity clamping in a filament. Nevertheless, significant changes in radiation intensity are noticeable, and this is essentially due to variation in the number density of emitting atoms. The present results also explain the near absence of ion emission but strong atomic neutral emission from plumes produced during fs LIBS in air. PMID:26480372

  15. Photosynthesis of C3, C3-C4, and C4 grasses at glacial CO2.

    PubMed

    Pinto, Harshini; Sharwood, Robert E; Tissue, David T; Ghannoum, Oula

    2014-07-01

    Most physiology comparisons of C3 and C4 plants are made under current or elevated concentrations of atmospheric CO2 which do not reflect the low CO2 environment under which C4 photosynthesis has evolved. Accordingly, photosynthetic nitrogen (PNUE) and water (PWUE) use efficiency, and the activity of the photosynthetic carboxylases [Rubisco and phosphoenolpyruvate carboxylase (PEPC)] and decarboxylases [NADP-malic enzyme (NADP-ME) and phosphoenolpyruvate carboxykinase (PEP-CK)] were compared in eight C4 grasses with NAD-ME, PCK, and NADP-ME subtypes, one C3 grass, and one C3-C4 grass grown under ambient (400 μl l(-1)) and glacial (180 μl l(-1)) CO2. Glacial CO2 caused a smaller reduction of photosynthesis and a greater increase of stomatal conductance in C4 relative to C3 and C3-C4 species. Panicum bisulcatum (C3) acclimated to glacial [CO2] by doubling Rubisco activity, while Rubisco was unchanged in Panicum milioides (C3-C4), possibly due to its high leaf N and Rubisco contents. Glacial CO2 up-regulated Rubisco and PEPC activities in concert for several C4 grasses, while NADP-ME and PEP-CK activities were unchanged, reflecting the high control exerted by the carboxylases relative to the decarboxylases on the efficiency of C4 metabolism. Despite having larger stomatal conductance at glacial CO2, C4 species maintained greater PWUE and PNUE relative to C3-C4 and C3 species due to higher photosynthetic rates. Relative to other C4 subtypes, NAD-ME and PEP-CK grasses had the highest PWUE and PNUE, respectively; relative to C3, the C3-C4 grass had higher PWUE and similar PNUE at glacial CO2. Biomass accumulation was reduced by glacial CO2 in the C3 grass relative to the C3-C4 grass, while biomass was less reduced in NAD-ME grasses compared with NADP-ME and PCK grasses. Under glacial CO2, high resource use efficiency offers a key evolutionary advantage for the transition from C3 to C4 photosynthesis in water- and nutrient-limited environments. PMID:24723409

  16. 30 CFR 250.1158 - How do I receive approval to downhole commingle hydrocarbons?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... hydrocarbons? 250.1158 Section 250.1158 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT... downhole commingle hydrocarbons? (a) Before you perforate a well, you must request and receive approval from the Regional Supervisor to commingle hydrocarbons produced from multiple reservoirs within...

  17. 30 CFR 250.1158 - How do I receive approval to downhole commingle hydrocarbons?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... hydrocarbons? 250.1158 Section 250.1158 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND... approval to downhole commingle hydrocarbons? (a) Before you perforate a well, you must request and receive approval from the Regional Supervisor to commingle hydrocarbons produced from multiple reservoirs within...

  18. 30 CFR 250.1158 - How do I receive approval to downhole commingle hydrocarbons?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... hydrocarbons? 250.1158 Section 250.1158 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT... downhole commingle hydrocarbons? (a) Before you perforate a well, you must request and receive approval from the Regional Supervisor to commingle hydrocarbons produced from multiple reservoirs within...

  19. 30 CFR 250.1158 - How do I receive approval to downhole commingle hydrocarbons?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... hydrocarbons? 250.1158 Section 250.1158 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT... downhole commingle hydrocarbons? (a) Before you perforate a well, you must request and receive approval from the Regional Supervisor to commingle hydrocarbons produced from multiple reservoirs within...

  20. Downhole geothermal well sensors comprising a hydrogen-resistant optical fiber

    DOEpatents

    Weiss, Jonathan D.

    2005-02-08

    A new class of optical fiber based thermal sensors has been invented. The new sensors comprise hydrogen-resistant optical fibers which are able to withstand a hot, hydrogen-containing environment as is often found in the downhole well environment.

  1. The Resolved Outflow from 3C 48

    NASA Astrophysics Data System (ADS)

    Shih, Hsin-Yi; Stockton, Alan

    2014-10-01

    We investigate the properties of the high-velocity outflow driven by the young radio jet of 3C 48, a compact-steep-spectrum source. We use the Space Telescope Imaging Spectrograph on board the Hubble Space Telecope to obtain (1) low-resolution UV and optical spectra and (2) multi-slit medium-resolution spectra of the ionized outflow. With supporting data from ground-based spectrographs, we are able to accurately measure the ratios of diagnostic emission lines such as [O III] λ5007, [O III] λ3727, [N II] λ6548, Hα, Hβ, [Ne V] λ3425, and [Ne III] λ3869. We fit the observed emission-line ratios using a range of ionization models, powered by active galactic nucleus (AGN) radiation and shocks, produced by the MAPPINGS code. We have determined that AGN radiation is likely the dominant ionization source. The outflow's density is estimated to be in the range n = 103-104 cm-3, the mass is ~6 × 106 M ⊙, and the metallicity is likely equal to or higher than solar. Compared with the typical outflows associated with more evolved radio jets, this young outflow is denser, less massive, and more metal rich. Multi-slit observations allow us to construct a two-dimensional velocity map of the outflow that shows a wide range of velocities with distinct velocity components, suggesting a wide-angle clumpy outflow. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program GO-11574. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. Some of the

  2. THE ACCELERATING JET OF 3C 279

    SciTech Connect

    Bloom, S. D.; Fromm, C. M.; Ros, E.

    2013-01-01

    Analysis of the proper motions of the subparsec scale jet of the quasar 3C 279 at 15 GHz with the Very Long Baseline Array shows significant accelerations in four of nine superluminal features. Analysis of these motions is combined with the analysis of flux density light curves to constrain values of Lorentz factor and viewing angle (and their derivatives) for each component. The data for each of these components are consistent with significant changes to the Lorentz factor, viewing angle, and azimuthal angle, suggesting jet bending with changes in speed. We see that for these observed components Lorentz factors are in the range {Gamma} = 10-41, viewing angles are in the range thetav = 0. Degree-Sign 1-5. Degree-Sign 0, and intrinsic (source frame) flux density is in the range, F{sub {nu},int} 1.5 Multiplication-Sign 10{sup -9}-1.5 Multiplication-Sign 10{sup -5} Jy. Considering individual components, the Lorentz factors vary from {Gamma} = 11-16 for C1, {Gamma} = 31-41 for C5, {Gamma} = 29-41 for C6, and {Gamma} = 9-12 for C8, indicating that there is no single underlying flow speed to the jet and likely we are seeing pattern speeds from shocks in the jet. The viewing angles vary in time from 0. Degree-Sign 6 to 1. Degree-Sign 5 in the case of C1 (the least extreme example), from 0. Degree-Sign 5 to 5. Degree-Sign 0 in the case of C8, and from 0. Degree-Sign 1 to 0. Degree-Sign 9 for C5 (the last two being the most extreme examples). The intrinsic flux density varies by factors from 1.4 for C8 and 430 for C5. Theoretical analysis of the accelerations also indicates potential jet bending. In addition, for one component, C5, polarization measurements also set limits to the trajectory of the jet.

  3. Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma

    SciTech Connect

    J. Ford Brett; Robert V. Westermark

    2001-03-31

    The objective of this project is to demonstrate the impact of downhole vibration stimulation on oil production rates in a mature waterflood field. Oil & Gas Consultants International, Inc. (OGCI) will manage the project in close cooperation with the Osage Tribe as the tests will be conducted in Osage County, Oklahoma, the mineral estate of the Osage Tribe. The field is owned and operated by Calumet Oil Company. Phillips Petroleum Company will contribute their proprietary vibration core analysis of cores recovered from the pilot test area. To achieve the project objectives, the work has been divided into nine tasks, some are concurrent, while other tasks rely on completion of previous steps. The operator, Calumet Oil Company operates several field in Osage County Oklahoma. The North Burbank Unit will be the site of the test. The team will then determine where within the field to optimally locate the vibration test well. With the location determined, the test well will be drilled, cored, logged and 7-inch production casing run and cemented. In a parallel effort, OGCI will be designing, building, and testing a new version of the downhole vibration tool based on their patented and field proven whirling orbital vibrator. With the field test tool built to run in 7-inch casing. Reliability testing of the downhole tool and surface power source will be conducted in nearby field operated by Calumet Oil Company. After the core is recovered, Phillips Petroleum Company will be conducting laboratory tests utilizing their proprietary sonic core apparatus to determine fluid flow response to a range of vibration frequencies. These results, in turn, will allow final adjustments to the frequency generation mechanisms of the downhole vibration tool. One or more offset wells, near to the vibration test well, will be equipped with downhole geophones and or hydro-phones to determine the strength of signal and if the producing formation has a characteristic resonant frequency response

  4. A band clamp with a spring toggle lever

    NASA Technical Reports Server (NTRS)

    Simmonds, M.

    1974-01-01

    Clamp could have several applications, as it provides tolerance for both expansion and contraction. It might be useful with firemen's breathing apparatus and luggage racks and other freight-carrying equipment. Also, using same piece as handle and spring reduces production costs by reducing number of parts.

  5. 30 CFR 18.40 - Cable clamps and grips.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design...) cables to prevent strain on the cable terminals of a machine. Also insulated clamps shall be provided to prevent strain on both ends of each cable or cord leading from a machine to a detached or...

  6. Mechanical stability of multidomain proteins and novel mechanical clamps.

    PubMed

    Sikora, Mateusz; Cieplak, Marek

    2011-06-01

    We estimate the size of mechanostability for 318 multidomain proteins which are single-chain and contain up to 1021 amino acids. We predict existence of novel types of mechanical clamps in which interdomain contacts play an essential role. Mechanical clamps are structural regions which are the primary source of a protein's resistance to pulling. Among these clamps there is one that opposes tensile stress due to two domains swinging apart. This movement strains and then ruptures the contacts that hold the two domains together. Another clamp also involves tensile stress but it originates from an immobilization of a structural region by a surrounding knot-loop (without involving any disulfide bonds). Still another mechanism involves shear between helical regions belonging to two domains. We also consider the amyloid-prone cystatin C which provides an example of a two-chain 3D domain-swapped protein. We predict that this protein should withstand remarkably large stress, perhaps of order 800 pN, when inducing a shearing strain. The survey is generated through molecular dynamics simulations performed within a structure-based coarse grained model. PMID:21465555

  7. 21 CFR 882.5175 - Carotid artery clamp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Carotid artery clamp. 882.5175 Section 882.5175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... (the principal artery in the neck that supplies blood to the brain) and has a removable...

  8. 21 CFR 882.5175 - Carotid artery clamp.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Carotid artery clamp. 882.5175 Section 882.5175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... (the principal artery in the neck that supplies blood to the brain) and has a removable...

  9. 21 CFR 882.5175 - Carotid artery clamp.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Carotid artery clamp. 882.5175 Section 882.5175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... (the principal artery in the neck that supplies blood to the brain) and has a removable...

  10. 21 CFR 882.5175 - Carotid artery clamp.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Carotid artery clamp. 882.5175 Section 882.5175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... (the principal artery in the neck that supplies blood to the brain) and has a removable...

  11. 21 CFR 882.5175 - Carotid artery clamp.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Carotid artery clamp. 882.5175 Section 882.5175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... (the principal artery in the neck that supplies blood to the brain) and has a removable...

  12. Management of Senile Ptosis with Levator Muscle Resection Using the Putterman Clamp

    PubMed Central

    2016-01-01

    Summary: Putterman clamp, a muscle clamp, is commonly used in conjunctival müllerectomies. We report 3 cases of senile ptosis repaired with levator muscle resection using the Putterman clamp. The redundant levator aponeurosis was removed with electrocautery after clamping with the Putterman clamp. The levator muscle was refixed to the tarsus with three 4-0 Vicryl stitches after adjusting the height of the eyelid fissure. No intraoperative difficulties were encountered. Ecchymosis and edema were limited in the immediate postoperative period. No complications were noted during the follow-up. The benefits of using the Putterman clamp in levator muscle resection are illustrated in these cases. PMID:27482474

  13. Management of Senile Ptosis with Levator Muscle Resection Using the Putterman Clamp.

    PubMed

    Yang, Ju-Wen

    2016-06-01

    Putterman clamp, a muscle clamp, is commonly used in conjunctival müllerectomies. We report 3 cases of senile ptosis repaired with levator muscle resection using the Putterman clamp. The redundant levator aponeurosis was removed with electrocautery after clamping with the Putterman clamp. The levator muscle was refixed to the tarsus with three 4-0 Vicryl stitches after adjusting the height of the eyelid fissure. No intraoperative difficulties were encountered. Ecchymosis and edema were limited in the immediate postoperative period. No complications were noted during the follow-up. The benefits of using the Putterman clamp in levator muscle resection are illustrated in these cases. PMID:27482474

  14. Vibration control of a flexible clamped-clamped plate based on an improved FULMS algorithm and laser displacement measurement

    NASA Astrophysics Data System (ADS)

    Xie, Lingbo; Qiu, Zhi-cheng; Zhang, Xian-min

    2016-06-01

    This paper presents a novel active resonant vibration control experiment of a flexible clamped-clamped plate using an improved filtered-U least mean square (FULMS) algorithm and laser displacement measurement. Different from the widely used PZT sensors or acceleration transducers, the vibration of the flexible clamped-clamped plate is measured by a non-contact laser displacement measurement sensor with higher measurement accuracy and without additional load to the plate. The conventional FULMS algorithm often uses fixed step size and needs reference signal related to the external disturbance signal. However, the fixed step size method cannot obtain a fast convergence speed and it will result in a low residual error. Thus, a variable step size method is investigated. In addition, it is difficult to extract reference signal related to the vibration source directly in the practical application. Therefore, it is practically useful that a reference signal is constructed by both the controller parameters and the vibration residual signal. The experimental results demonstrate that the improved FULMS algorithm has better vibration control effect than the proportional derivative (PD) feedback control algorithm and the fixed step-size control algorithm.

  15. Review: The lord of the rings: Structure and mechanism of the sliding clamp loader.

    PubMed

    Kelch, Brian A

    2016-08-01

    Sliding clamps are ring-shaped polymerase processivity factors that act as master regulators of cellular replication by coordinating multiple functions on DNA to ensure faithful transmission of genetic and epigenetic information. Dedicated AAA+ ATPase machines called clamp loaders actively place clamps on DNA, thereby governing clamp function by controlling when and where clamps are used. Clamp loaders are also important model systems for understanding the basic principles of AAA+ mechanism and function. After nearly 30 years of study, the ATP-dependent mechanism of opening and loading of clamps is now becoming clear. Here I review the structural and mechanistic aspects of the clamp loading process, as well as comment on questions that will be addressed by future studies. © 2016 Wiley Periodicals, Inc. Biopolymers 105: 532-546, 2016. PMID:26918303

  16. Downhole well log and core montages from the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope

    USGS Publications Warehouse

    Collett, T.S.; Lewis, R.E.; Winters, W.J.; Lee, M.W.; Rose, K.K.; Boswell, R.M.

    2011-01-01

    The BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well was an integral part of an ongoing project to determine the future energy resource potential of gas hydrates on the Alaska North Slope. As part of this effort, the Mount Elbert well included an advanced downhole geophysical logging program. Because gas hydrate is unstable at ground surface pressure and temperature conditions, a major emphasis was placed on the downhole-logging program to determine the occurrence of gas hydrates and the in-situ physical properties of the sediments. In support of this effort, well-log and core data montages have been compiled which include downhole log and core-data obtained from the gas-hydrate-bearing sedimentary section in the Mount Elbert well. Also shown are numerous reservoir parameters, including gas-hydrate saturation and sediment porosity log traces calculated from available downhole well log and core data. ?? 2010.

  17. GONAF - A deep Geophysical Observatory at the North Anatolian Fault: Permanent downhole monitoring of a pending major earthquake

    NASA Astrophysics Data System (ADS)

    Bulut, Fatih; Bohnhoff, Marco; Dresen, Georg; Raub, Christina; Kilic, Tugbay; Kartal, Recai F.; Tuba Kadirioglu, F.; Nurlu, Murat; Ito, Hisao; Malin, Peter E.

    2014-05-01

    The North Anatolian Fault Zone (NAFZ hereafter) is a right-lateral transform plate boundary between the Anatolian plate and Eurasia accommodating a relative plate motion of ~25 mm/yr. Almost the entire fault zone has failed during the last century as a westward migrating sequence of destructive earthquakes leaving a very high probability of a forthcoming large event to the Sea of Marmara segments. This area did not host any M>7 earthquake since 1766. Therefore, listening to the Sea of Marmara segments at a very low detection threshold is required to address how the brittle deformation develops along a critically-stressed fault segment prior to a potential failure. GONAF-ICDP project has been developed to design a downhole seismic network surrounding the Sea of Marmara segments of the NAFZ deploying 300 m deep boreholes equipped with a chain of sensitive seismographs. Natural and city-induced noise is attenuated through the unconsolidated subsurface formation and therefore provides ideal boundary conditions for seismic monitoring within the intact rocks at greater depths. A typical GONAF borehole consists of 1 Hz vertical sensor at every 75 m depth increment and a combination of 1Hz, 2Hz and 15 Hz 3C sensors at 300 m depth. By now, three boreholes were successfully implemented in the Tuzla and Yalova-Çınarcık regions. The plan is to complete four more GONAF boreholes in 2014. Our preliminary results show that GONAF waveform recordings will broaden the magnitude range down to ~M -1 in the target area providing a better characterization of seismically active features in time and space.

  18. Patch Clamp Experiments under Conditions of Variable Graviy

    NASA Astrophysics Data System (ADS)

    Kohn, F. P. M.; Meissner, K.

    2013-02-01

    The cellular membrane is an intrinsic part of any cell. It has a complex composition of lipid molecules and proteins. The membrane is, among others, involved in excitation and signal transduction. Ion channels, as integral membrane proteins, play an important role. For the question of gravity sensitivity of biological systems, especially neuronal cells, ion channels are of high interest. Gravity might directly interact with the ion channel protein or it might change the thermodynamic membrane parameters, influencing the incorporated proteins indirectly. Detailed information about the effects of gravity on the function of single ion-channels can up to now only be acquired by electrophysiological approaches like the patch clamp technique. Today this technique is the preferentially used technique for single ion-channel studies. Consequently, experiments have been developed in recent years to investigate the interaction of gravity with single ion channel molecules utilizing the patch-clamp technology on different macro- and micro-gravity platforms.

  19. Patch Clamp Recording of Ion Channels Expressed in Xenopus Oocytes

    PubMed Central

    L Brown, Austin; E. Johnson, Brandon; B. Goodman, Miriam

    2008-01-01

    Since its development by Sakmann and Neher 1, 2, the patch clamp has become established as an extremely useful technique for electrophysiological measurement of single or multiple ion channels in cells. This technique can be applied to ion channels in both their native environment and expressed in heterologous cells, such as oocytes harvested from the African clawed frog, Xenopus laevis. Here, we describe the well-established technique of patch clamp recording from Xenopus oocytes. This technique is used to measure the properties of expressed ion channels either in populations (macropatch) or individually (single-channel recording). We focus on techniques to maximize the quality of oocyte preparation and seal generation. With all factors optimized, this technique gives a probability of successful seal generation over 90 percent. The process may be optimized differently by every researcher based on the factors he or she finds most important, and we present the approach that have lead to the greatest success in our hands. PMID:19078941

  20. Glycine decarboxylase in C3, C4 and C3-C4 intermediate species.

    PubMed

    Schulze, Stefanie; Westhoff, Peter; Gowik, Udo

    2016-06-01

    The glycine decarboxylase complex (GDC) plays a central role in photorespiration. GDC is localized in the mitochondria and together with serine hydroxymethyltransferase it converts two molecules of glycine to one molecule of serine, CO2 and NH3. Overexpression of GDC subunits in the C3 species Arabidopsis thaliana can increase the metabolic flux through the photorespiratory pathway leading to enhanced photosynthetic efficiency and consequently to an enhanced biomass production of the transgenic plants. Changing the spatial expression patterns of GDC subunits was an important step during the evolution of C3-C4 intermediate and likely also C4 plants. Restriction of the GDC activity to the bundle sheath cells led to the establishment of a photorespiratory CO2 pump. PMID:27038285

  1. DNA Sliding Clamps: Just the Right Twist to Load onto DNA

    SciTech Connect

    Barsky, D; Venclovas, C

    2005-10-24

    Two recent papers illuminate a long sought step in DNA sliding clamp loading. One paper reveals the structure of the PCNA clamp wrapped around DNA--still open from being loaded--while a second paper discovers that the clamp may assist this process by forming a right-handed helix upon opening.

  2. Oscillations and latency in the clamped pupil light reflex

    NASA Astrophysics Data System (ADS)

    Milton, John G.; Ohira, Toru; Steck, Jeff; Crate, John; Longtin, Andre

    1993-11-01

    It is shown that the pupil latency can be estimated from pupil cycling measurements when the pupil light reflex is clamped with piecewise constant negative feedback. The solution of the mathematical model previously shown to describe these oscillations is utilized to develop a variety of strategies to estimate latency and to evaluate the effects of noise on these estimates. The results demonstrate that the pupil latency shows considerable variation.

  3. Acute aortic dissection from cross-clamp injury.

    PubMed

    Litchford, B; Okies, J E; Sugimura, S; Starr, A

    1976-11-01

    Acute dissection of the ascending aorta secondary to cross-clamp injury can be successfully managed if the problem is recognized immediately. Bypass must be instituted after recannulation at a point distal to the innominate artery so that proper exposure of the site of injury can be obtained. Systemic as well as local hypothermia for myocardial preservation are both necessary. Direct suture closure of all layers at the site of dissection over Teflon felt can terminate this process. PMID:979312

  4. From Galvani to patch clamp: the development of electrophysiology.

    PubMed

    Verkhratsky, Alexei; Krishtal, O A; Petersen, Ole H

    2006-12-01

    The development of electrophysiology is traced from the early beginnings represented by the work of the Dutch microscopist, Jan Swammerdam, in the 17th century through the first notion of an aqueous transmembrane pore as a substrate of excitability made by Luigi Galvani in late 18th century to the invention late in the 20th century of the patch-clamp technique by Erwin Neher and Bert Sakmann. PMID:17072639

  5. Force-clamp laser trapping of rapidly interacting molecules

    NASA Astrophysics Data System (ADS)

    Capitanio, Marco; Monico, Carina; Vanzi, Francesco; Pavone, Francesco S.

    2013-06-01

    Forces play a fundamental role in a wide array of biological processes, regulating enzymatic activity, kinetics of molecular bonds, and molecular motors mechanics. Single molecule force spectroscopy techniques have enabled the investigation of such processes, but they are inadequate to probe short-lived (millisecond and sub-millisecond) molecular complexes. We developed an ultrafast force-clamp spectroscopy technique that uses a dual trap configuration to apply constant loads to a single intermittently interacting biological polymer and a binding protein. Our system displays a delay of only ˜10 μs between formation of the molecular bond and application of the force and is capable of detecting interactions as short as 100 μs. The force-clamp configuration in which our assay operates allows direct measurements of load-dependence of lifetimes of single molecular bonds. Moreover, conformational changes of single proteins and molecular motors can be recorded with sub-nanometer accuracy and few tens of microseconds of temporal resolution. We demonstrate our technique on molecular motors, using myosin II from fast skeletal muscle and on protein-DNA interaction, specifically on Lactose repressor (LacI). The apparatus is stabilized to less than 1 nm with both passive and active stabilization, allowing resolving specific binding regions along the actin filament and DNA molecule. Our technique extends single-molecule force-clamp spectroscopy to molecular complexes that have been inaccessible up to now, opening new perspectives for the investigation of the effects of forces on biological processes.

  6. On the Y-chromosome haplogroup C3c classification.

    PubMed

    Malyarchuk, Boris A; Derenko, Miroslava; Denisova, Galina

    2012-10-01

    As there are ambiguities in classification of the Y-chromosome haplogroup C3c, relatively frequent in populations of Northern Asia, we analyzed all three haplogroup-defining markers M48, M77 and M86 in C3-M217-individuals from Siberia, Eastern Asia and Eastern Europe. We have found that haplogroup C3c is characterized by the derived state at M48, whereas mutations at both M77 and M86 define subhaplogroup C3c1. The branch defined by M48 alone would belong to subhaplogroup C3c*, characteristic for some populations of Central and Eastern Siberia, such as Koryaks, Evens, Evenks and Yukaghirs. Subhaplogroup C3c* individuals could be considered as remnants of the Neolithic population of Siberia, based on the age of C3c*-short tandem repeat variation amounting to 4.5 ± 2.4 thousand years. PMID:22810113

  7. Simulation analysis of the oil/water structure in the downhole with presence of hydrocyclone separator

    NASA Astrophysics Data System (ADS)

    Jamil, I. E.; Al-Kayiem, H. H.

    2015-12-01

    The maturing oil fields with increasing water production can pose a challenge in terms of produced water handling and disposal issues. This paper presents the modelling and simulation procedure of the two-phase flow of water/oil in a downhole using ANSYS- FLUENT 14 software. The developed procedure successfully simulated the production zone and the interaction of the two fluids in a natural environment where the reservoir pressure is the sole driving force. The results show significant difference of volume distribution in the flows with different oil content. The model can become an essential tool to assist in prediction of the behavior of oil/water mixture flow in the wellbores, and to serve in designing downhole oil/water separators.

  8. A history of downhole scale inhibition by squeeze treatments on the Murchison platform

    SciTech Connect

    Payne, G.E.

    1987-01-01

    The formation water of the Murchison reservoir has a natural scaling potential. As pressure reduces from reservoir conditions carbonate scaling can occur. Also the water has a barium and strontium content so that when injected seawater broke through to the producing wells sulphate scaling also became possible. Initial scale inhibitor squeeze treatments achieved what scale itself to that date had not. They plugged the wells. Since then scale inhibitor squeezes have been successfully carried out and regularly achieve squeeze lives of up to a year. This paper outlines in historical form the philosophies and events of downhole scale inhibition for the Murchison wells. The initial difficulties and present successes are described. Details are also given of previous problem areas of downhole asphaltene deposition and present thoughts on squeeze treating different producing zones within the same wellbore.

  9. High-Temperature Motor Windings for Downhole Pumps Used in Geothermal Energy Production

    SciTech Connect

    Hooker, Matthew; Hazelton, Craig; Kano, Kimi

    2010-12-31

    The development of highly reliable downhole equipment is an essential element in enabling the widespread utilization of Enhanced Geothermal Systems (EGS). The downhole equipment used in these systems will be required to operate at high voltages and temperatures on the order of 200 to 250°C (and eventually to 300°C). These conditions exceed the practical operating ranges of currently available thermoplastic wire insulations, and thus limit the operating lifetime of tools such as Electric Submersible Pumps (ESPs). In this work, high-temperature insulations based on composite materials were developed and demonstrated. The products of this work were found to exhibit electrical resistivities and dielectric breakdown strengths that PEEK at temperatures above 250C. In addition, sub-scale motor windings were fabricated and tested to validate the performance of this technology

  10. Evaluation of a direct contact downhole steam generator in a field environment. Final results

    SciTech Connect

    Marshall, B.W.; Moreno, J.B.; Muir, J.F.

    1983-01-01

    A test program to demonstrate the operation of downhole steam generators (DSG) in an oil field environment was conducted in the Wilmington Field at Long Beach, CA. Two DSG design variations were used. One burned diesel fuel in air and was placed downhole; the other burned diesel in oxygen and was located on the surface. Gas communication was established with all wells in the production patterns. Relative rates of movement of nitrogen, CO/sub 2/ and CO were inferred and the wells were monitored for any production changes. Operating lifetimes of both prototype units were limited by the corrosion of various system components. Metallurgical analyses of degraded components of the generator and support systems have been completed.

  11. An Internal Coaxial Cable Electrical Connector For Use In Downhole Tools

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Fox, Joe; Sneddon, Cameron; Briscoe, Michael

    2005-11-29

    A coaxial cable electrical connector more specifically an internal coaxial cable connector placed within a coaxial cable and its constituent components. A coaxial cable connector is in electrical communcation with an inductive transformer and a coaxial cable. The connector is in electrical communication with the outer housing of the inductive transfonner. A generally coaxial center conductor, a portion of which could be the coil in the inductive transformer, passes through the connector, is electrically insulated from the connector, and is in electrical communication with the conductive care of the coaxial cable. A plurality of bulbous pliant tabs on the coaxial cable connector mechanically engage the inside diameter of the coaxial cable thus grounding the transformer to the coaxial cable. The coaxial cable and inductive transformer are disposed within downhole tools to transmit electrical signals between downhole tools within a drill string.

  12. Linear and radial flow targets for characterizing downhole flow in perforations

    SciTech Connect

    Deo, M. ); Tariq, S.M. ); Halleck, P.M. )

    1989-08-01

    Two types of sandstone targets are commonly used to test flow efficiency of shaped-charge jet perforations: linear targets, in which flow enters only the unperforated end of the cylindrical sample, and radial targets, in which flow enters through the end and sides of the sample. To determine which of these targets best represents downhole conditions, the flow distribution along the length of a perforation has been studied by three-dimensional (3D) finite-element analyses. Linear and radial laboratory targets have been compared with downhole perforations under varying conditions. For ideal perforations, the low-shot-density (LSD) case is adequately represented by the radial target, while the high-shot-density (HSD) case falls between the two targets. With realistic crushed and damaged zones, the HSD closely matches the linear target, and the LSD case falls between the two targets.

  13. Biased insert for installing data transmission components in downhole drilling pipe

    DOEpatents

    Hall, David R.; Briscoe, Michael A.; Garner, Kory K.; Wilde, Tyson J.

    2007-04-10

    An apparatus for installing data transmission hardware in downhole tools includes an insert insertable into the box end or pin end of drill tool, such as a section of drill pipe. The insert typically includes a mount portion and a slide portion. A data transmission element is mounted in the slide portion of the insert. A biasing element is installed between the mount portion and the slide portion and is configured to create a bias between the slide portion and the mount portion. This biasing element is configured to compensate for varying tolerances encountered in different types of downhole tools. In selected embodiments, the biasing element is an elastomeric material, a spring, compressed gas, or a combination thereof.

  14. Downhole steam generator using low-pressure fuel and air supply

    DOEpatents

    Fox, R.L.

    1981-01-07

    For tertiary oil recovery, an apparatus for downhole steam generation is designed in which water is not injected directly onto the flame in the combustor, the combustion process is isolated from the reservoir pressure, the fuel and oxidant are supplied to the combustor at relatively low pressures, and the hot exhaust gases is prevented from entering the earth formation but is used to preheat the fuel and oxidant and water. The combustion process is isolated from the steam generation process. (DLC)

  15. Applications of a downhole programmable microprocessor for a geothermal borehole inspection tool

    SciTech Connect

    Jermance, R.L.; Moore, T.K.; Archuleta, J.; Hinz, K.

    1987-01-01

    The high-temperature scanning borehole inspection system is currently being developed jointly by the Los Alamos National Laboratory (LANL) and Westfalische Berggewerkschaftskasse (WBK) of West Germany. The downhole instrument is a digital televiewer that utilized a microprocessor to digitize, process and transmit the acoustic information to the surface acquisition and control system. The primary operation of the downhole acoustic assembly uses a piezoelectric crystal acting as a receiver-transmitter which is mounted on the rotating head. The crystal emits a burst of acoustic energy that propagates through the borehole fluid with a portion of the energy reflected by the borehole wall back to the crystal. The time of travel and the amplitude of the reflected signal are conditioned by the microprocessor and transmitted along with other pertinent data to the surface data processing center. This instrument has been designed specifically for use in geothermal borehole environments to determine the location of fractures intersecting the borehole and provide information concerning overall borehole conditions. It may also be used for definitive casing inspection. The instrument essentially eliminates operator interaction for downhole control and simplifies assembly and maintenance procedures.

  16. The surface area modulation downhole telemetry system for measurement while drilling

    SciTech Connect

    Mansure, A.J.; Keefe, R.G.; Caffey, T.W.H.; Bartel, L.C.; Ballard, S.

    1998-04-01

    The need for a reliable, fast, wireless telemetry system in the drilling industry is great but the technical challenge to develop such a system is huge. A downhole wireless telemetry system based on Surface Area Modulation (SAM) has been developed which involves the introduction of an electrically insulated gap near the bottom of an otherwise conductive drillstring. The electrical resistance of this gap can be modulated to alter the electrical characteristics of a circuit involving a surface power supply, the sections of the drillstring above and below the gap, the earth, and a nearby return electrode. These changes alter the current in the circuit, which can be monitored at the surface with an ammeter. Downhole data are encoded and transmitted to the surface as a pattern of current oscillations. In a field test, the SAM system successfully transmitted downhole information from depths of 1,400 ft below the fluid level to the surface at a rate of 110 baud. Electrical insulation on the outside of the simulated drillstring was required to achieve this level of performance. Electrically insulated tubing improved the data transmission rate at a given depth by more than an order of magnitude, and increased the maximum depth from which successful data telemetry could be achieved by more than a factor of two.

  17. Development and operation of a high-pressure downhole steam generator

    SciTech Connect

    Marshall, B.W.

    1982-01-01

    Injection of thermal energy is an often used treatment to enhance the production from reservoirs which contain heavy oil. Historically steam is generated on the surface in conventional boilers and supplied downhole to the reservoir through tubing which, until recent years, was uninsulated. Changing economic conditions have stimulated development of techniques to more efficiently deliver thermal energy to the reservoir sandface. The US Department of Energy has sponsored a program that includes the development of a downhole steam generator which can be placed at the bottom of a well and inject not only the steam but also combustion products directly into the reservoir. The advantages of this include no exhaust products directly on the surface, no heat loss in downhole tubing, and perhaps an additive effect of the exhaust carbon dioxide on the reservoir. After design and laboratory development, a three phase test program, culminating in a long term field operation, was successfully completed. The system design and field operation experiences are reported in this paper.

  18. An Internal Coaxial Cable Electrical Connector For Use In Downhole Tools

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Fox, Joe; Sneddon, Cameron; Briscoe, Michael

    2005-09-20

    A seal for a coaxial cable electrical connector more specifically an internal seal for a coaxial cable connector placed within a coaxial cable and its constituent components. A coaxial cable connector is in electrical communcation with an inductive transformer and a coaxial cable. The connector is in electrical communication with the outer housing of the inductive transformer. A generally coaxial center conductor, a portion of which could be the coil in the inductive transformer, passes through the connector, is electrically insulated from the connector, and is in electrical communication with the conductive core of the coaxial cable. The electrically insulating material also doubles as a seal to safegaurd against penetration of fluid, thus protecting against shorting out of the electrical connection. The seal is a multi-component seal, which is pre-compressed to a desired pressure rating. The coaxial cable and inductive transformer are disposed within downhole tools to transmit electrical signals between downhole tools within a drill string. The internal coaxial cable connector and its attendant seal can be used in a plurality of downhole tools, such as sections of pipe in a drill string, drill collars, heavy weight drill pipe, and jars.

  19. Self-tuning behavior of a clamped-clamped beam with sliding proof mass for broadband energy harvesting

    NASA Astrophysics Data System (ADS)

    Pillatsch, P.; Miller, L. M.; Halvorsen, E.; Wright, P. K.; Yeatman, E. M.; Holmes, A. S.

    2013-12-01

    Real world systems rarely vibrate at a single resonance frequency and the frequencies drift over time. Tunable devices exist, but generally need additional energy to achieve frequency adaptation. This means that the benefits in power output from this tuning need to be large enough to power the mechanism itself. Passively self-tuning systems go into resonance without requiring active control. This paper focuses on a passively self-tuning system with a proof mass that can slide freely along a clamped-clamped beam. Under external vibration, the slider moves along the beam until the system goes into resonance. A proof-of-concept design is introduced using either a copper or a steel beam and a 3D-printed ABS thermoplastic proof mass. Successful self-tuning is demonstrated in both cases. The frequencies range from 80 - 140 Hz at accelerations as low as 0.007 g rms. Results show the resonance of the beam and the position of the slider along the beam with time. Furthermore, the dynamic magnification and the proof mass position at resonance are discussed, together with the inherent non-linearities of double-clamped beam resonators. The findings support the hypothesis that the effect of the ratio between proof mass and beam mass outweighs the Duffing spring stiffening effects.

  20. Yeast Rad17/Mec3/Ddc1: A sliding clamp for the DNA damage checkpoint

    PubMed Central

    Majka, Jerzy; Burgers, Peter M. J.

    2003-01-01

    The Saccharomyces cerevisiae Rad24 and Rad17 checkpoint proteins are part of an early response to DNA damage in a signal transduction pathway leading to cell cycle arrest. Rad24 interacts with the four small subunits of replication factor C (RFC) to form the RFC-Rad24 complex. Rad17 forms a complex with Mec3 and Ddc1 (Rad17/3/1) and shows structural similarities with the replication clamp PCNA. This parallelism with a clamp-clamp loader system that functions in DNA replication has led to the hypothesis that a similar clamp-clamp loader relationship exists for the DNA damage response system. We have purified the putative checkpoint clamp loader RFC-Rad24 and the putative clamp Rad17/3/1 from a yeast overexpression system. Here, we provide experimental evidence that, indeed, the RFC-Rad24 clamp loader loads the Rad17/3/1 clamp around partial duplex DNA in an ATP-dependent process. Furthermore, upon ATP hydrolysis, the Rad17/3/1 clamp is released from the clamp loader and can slide across more than 1 kb of duplex DNA, a process which may be well suited for a search for damage. Rad17/3/1 showed no detectable exonuclease activity. PMID:12604797

  1. Effect of various irrigant and autoclaving regimes on the fracture resistance of rubber dam clamps.

    PubMed

    Sutton, J; Saunders, W P

    1996-09-01

    Rubber dam clamps are known to break during clinical use in endodontics. This in-vitro study examined some of the variables which may contribute to the fracture. Stainless steel rubber dam clamps were subjected to various cleaning and autoclaving regimes and exposure to various solutions of sodium hypochlorite (NaOCl). Each clamp was examined after four cycles of cleaning and exposure to NaOCl. During environmental exposure to NaOCl, the clamp was stressed over a perspex rod to simulate placement onto the crown of a tooth. Clamps were examined after each test cycle visually and microscopically, or immediately after breakage. Results suggested that the fractures were because of a stress corrosion cracking phenomenon. There was evidence of intergranular and transgranular cracking of the metal. Corrosion spots were seen on the surface of the clamps and fracture occurred mainly through these spots. A number of recommendations to reduce breakage of clamps have been suggested. PMID:9206417

  2. Nonlinear vibrations of fluid-filled clamped circular cylindrical shells

    NASA Astrophysics Data System (ADS)

    Karagiozis, K. N.; Amabili, M.; Païdoussis, M. P.; Misra, A. K.

    2005-12-01

    In this study, the nonlinear vibrations are investigated of circular cylindrical shells, empty or fluid-filled, clamped at both ends and subjected to a radial harmonic force excitation. Two different theoretical models are developed. In the first model, the standard form of the Donnell's nonlinear shallow-shell equations is used; in the second, the equations of motion are derived by a variational approach which permits the inclusion of constraining springs at the shell extremities and taking in-plane inertial terms into account. In both cases, the solution includes both driven and companion modes, thus allowing for a travelling wave in the circumferential direction; they also include axisymmetric modes to capture the nonlinear inward shell contraction and the correct type (softening) nonlinear behaviour observed in experiments. In the first model, the clamped beam eigenfunctions are used to describe the axial variations of the shell deformation, automatically satisfying the boundary conditions, leading to a 7 degree-of-freedom (dof) expansion for the solution. In the second model, rotational springs are used at the ends of the shell, which when large enough reproduce a clamped end; the solution involves a sine series for axial variations of the shell deformation, leading to a 54 dof expansion for the solution. In both cases the modal expansions satisfy the boundary conditions and the circumferential continuity condition exactly. The Galerkin method is used to discretize the equations of motion, and AUTO to integrate the discretized equations numerically. When the shells are fluid-filled, the fluid is assumed to be incompressible and inviscid, and the fluid structure interaction is described by linear potential flow theory. The results from the two theoretical models are compared with existing experimental data, and in all cases good qualitative and quantitative agreement is observed.

  3. Intensity clamping in the filament of femtosecond laser radiation

    SciTech Connect

    Kandidov, V P; Fedorov, V Yu; Tverskoi, O V; Kosareva, O G; Chin, S L

    2011-04-30

    We have studied numerically the evolution of the light field intensity and induced refractive index of a medium upon filamentation of femtosecond laser radiation in air. It is shown that the intensity clamping results from the dynamic balance of optical powers of nonlinear lenses, induced by radiation due to the Kerr nonlinearity of air, and laser plasma produced during photoionisation. We have found the relation between the peak values of the light field intensity and the electron density in laser-produced plasma, as well as the transverse sizes of the filament and the plasma channel. (effects of laser radiation on matter)

  4. Vibration of clamped right triangular thin plates: Accurate simplified solutions

    NASA Astrophysics Data System (ADS)

    Saliba, H. T.

    1994-12-01

    Use of the superposition techniques in the free-vibration analyses of thin plates, as they were first introduced by Gorman, has provided simple and effective solutions to a vast number of rectangular plate problems. A modified superposition method is presented that is a noticeable improvement over existing techniques. It deals only with simple support conditions, leading to a simple, highly accurate, and very economical solution to the free-vibration problem of simply-supported right angle triangular plates. The modified method is also applicable to clamped-edge conditions.

  5. Normal-Pressure Tests of Circular Plates with Clamped Edges

    NASA Technical Reports Server (NTRS)

    Mcpherson, Albert E; Ramberg, Walter; Levy, Samuel

    1942-01-01

    A fixture is described for making normal-pressure tests of flat plates 5 inches in diameter in which particular care was taken to obtain rigid clamping at the edges. Results are given for 19 plates, ranging in thickness form 0.015 to 0.072 inch. The center deflections and the extreme-fiber stresses at low pressures were found to agree with theoretical values; the center deflections at high pressures were 4 to 12 percent greater than the theoretical values. Empirical curves are derived of the pressure for the beginning of the permanent set as a function of the dimensions of the plate and the tensile properties of the material.

  6. A precessing relativistic jet model for 3C 449

    NASA Technical Reports Server (NTRS)

    Gower, A. C.; Hutchings, J. B.

    1982-01-01

    It is shown that the radio structure of 3C 449 can be matched with a model in which the jets are precessing and have relativistic (beta greater-than or equal to 0.4) velocities. The best-fit model implies a precession period of about 100,000 yr and a cone angle which increases with time. A similar model may be relevant for the radio structure of 3C 31. A brief discussion of the implications for 3C 449 is given.

  7. Field test of two high-pressure, direct-contact downhole steam generators. Volume III. Metallurgical analyses

    SciTech Connect

    Muir, J.F.; Weirick, L.J.; Pettit, F.S.

    1983-10-01

    Two prototype downhole steam generator (DSG) systems were operated in an oil field environment during a test in the Wilmington Field, Long Beach, CA, from June 1981 through March 1982. One generator burned diesel fuel in air and was located downhole, the other burned diesel in oxygen and was operated on the surface. Components of the two systems experienced varying degrees of corrosion during the test. Severe degradation of certain critical components limited the operating lifetimes of both steam generators. Metallurgical analyses of degraded components were performed to determine the causes and mechanisms of corrosion of materials exposed to the diesel combustion, generator effluent, and downhole environments. Two separate analyses were conducted reflecting the two classes of attack mechanisms encountered in these environments, i.e., aqueous corrosion and mixed gas hot corrosion. Materials examined included plain carbon steel, 310 and 316 stainless steels, Inconel 600 and 625, and Hastelloy X. The degradation of combustor materials was caused primarily by fluctuations in the combustion environment, notably composition and temperature, at exposed surfaces. Most of the materials examined were found to be unsuitable for extended life in the environments to which they were exposed. Stainless steels, in particular, are not recommended for continued use in downhole steam generators. Other recommendations are provided, including alternate materials, design modifications, and changes in operating procedures, which should improve the lifetime of downhole steam generators. 83 references, 83 figures, 10 tables.

  8. The human dynamic clamp as a paradigm for social interaction.

    PubMed

    Dumas, Guillaume; de Guzman, Gonzalo C; Tognoli, Emmanuelle; Kelso, J A Scott

    2014-09-01

    Social neuroscience has called for new experimental paradigms aimed toward real-time interactions. A distinctive feature of interactions is mutual information exchange: One member of a pair changes in response to the other while simultaneously producing actions that alter the other. Combining mathematical and neurophysiological methods, we introduce a paradigm called the human dynamic clamp (HDC), to directly manipulate the interaction or coupling between a human and a surrogate constructed to behave like a human. Inspired by the dynamic clamp used so productively in cellular neuroscience, the HDC allows a person to interact in real time with a virtual partner itself driven by well-established models of coordination dynamics. People coordinate hand movements with the visually observed movements of a virtual hand, the parameters of which depend on input from the subject's own movements. We demonstrate that HDC can be extended to cover a broad repertoire of human behavior, including rhythmic and discrete movements, adaptation to changes of pacing, and behavioral skill learning as specified by a virtual "teacher." We propose HDC as a general paradigm, best implemented when empirically verified theoretical or mathematical models have been developed in a particular scientific field. The HDC paradigm is powerful because it provides an opportunity to explore parameter ranges and perturbations that are not easily accessible in ordinary human interactions. The HDC not only enables to test the veracity of theoretical models, it also illuminates features that are not always apparent in real-time human social interactions and the brain correlates thereof. PMID:25114256

  9. 27 CFR 21.37 - Formula No. 3-C.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Formula No. 3-C. 21.37 Section 21.37 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specially Denatured Spirits Formulas and Authorized Uses § 21.37 Formula No. 3-C....

  10. 27 CFR 21.37 - Formula No. 3-C.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Formula No. 3-C. 21.37 Section 21.37 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specially Denatured Spirits Formulas and Authorized Uses § 21.37 Formula No. 3-C....

  11. Enhanced Oil Recovery with Downhole Vibrations Stimulation in Osage County, Oklahoma

    SciTech Connect

    J. Ford Brett; Robert V. Westermark

    2001-09-30

    This Technical Quarterly Report is for the reporting period July 1, 2001 to September 30, 2001. The report provides details of the work done on the project entitled ''Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma''. The project is divided into nine separate tasks. Several of the tasks are being worked on simultaneously, while other tasks are dependent on earlier tasks being completed. The vibration stimulation well is permitted as Well 111-W-27, section 8 T26N R6E Osage County Oklahoma. It was spud July 28, 2001 with Goober Drilling Rig No. 3. The well was drilled to 3090-feet cored, logged, cased and cemented. The Rig No.3 moved off August 6, 2001. Phillips Petroleum Co. has begun analyzing the cores recovered from the test well. Standard porosity, permeability and saturation measurements will be conducted. They will then begin the sonic stimulation core tests Calumet Oil Company, the operator of the NBU, has begun to collect both production and injection wells information to establish a baseline for the project in the pilot field test area. Green Country Submersible Pump Company, a subsidiary of Calumet Oil Company, will provide both the surface equipment and downhole tools to allow the Downhole Vibration Tool to be operated by a surface rod rotating system. The 7-inch Downhole Vibration Tool (DHVT) has been built and is ready for initial shallow testing. The shallow testing will be done in a temporarily abandoned well operated by Calumet Oil Co. in the Wynona waterflood unit. The data acquisition doghouse and rod rotating equipment have been placed on location in anticipation of the shallow test in Well No.20-12 Wynona Waterflood Unit. A notice of invention disclosure was submitted to the DOE Chicago Operations Office. DOE Case No.S-98,124 has been assigned to follow the documentation following the invention disclosure. A paper covering the material presented to the Oklahoma Geologic Survey (OGS)/DOE Annual Workshop in

  12. ENHANCED OIL RECOVERY WITH DOWNHOLE VIBRATION STIMULATION IN OSAGE COUNTY OKLAHOMA

    SciTech Connect

    Robert Westermark; J. Ford Brett

    2003-11-01

    This Final Report covers the entire project from July 13, 2000 to June 30, 2003. The report summarizes the details of the work done on the project entitled ''Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma'' under DOE Contract Number DE-FG26-00BC15191. The project was divided into nine separate tasks. This report is written in an effort to document the lessons learned during the completion of each task. Therefore each task will be discussed as the work evolved for that task throughout the duration of the project. Most of the tasks are being worked on simultaneously, but certain tasks were dependent on earlier tasks being completed. During the three years of project activities, twelve quarterly technical reports were submitted for the project. Many individual topic and task specific reports were included as appendices in the quarterly reports. Ten of these reports have been included as appendices to this final report. Two technical papers, which were written and accepted by the Society of Petroleum Engineers, have also been included as appendices. The three primary goals of the project were to build a downhole vibration tool (DHVT) to be installed in seven inch casing, conduct a field test of vibration stimulation in a mature waterflooded field and evaluate the effects of the vibration on both the produced fluid characteristics and injection well performance. The field test results are as follows: In Phase I of the field test the DHVT performed exceeding well, generating strong clean signals on command and as designed. During this phase Lawrence Berkeley National Laboratory had installed downhole geophones and hydrophones to monitor the signal generated by the downhole vibrator. The signals recorded were strong and clear. Phase II was planned to be ninety-day reservoir stimulation field test. This portion of the field tests was abruptly ended after one week of operations, when the DHVT became stuck in the well during a routine

  13. Program for the improvement of downhole drilling motor bearings and seals. Phase V. Final report

    SciTech Connect

    DeLafosse, P.H.; Tibbitts, G.A.; Black, A.D.; DiBona, B.G.

    1983-08-01

    The work done during the fifth and final phase of a program to improve downhole drilling motor bearing and seals is described. The principal activities in this phase were: (a) testing seals with abrasive-laden mud on the low-pressure side; (b) test second and third generation designs of both elastomeric chevron seals and Teflon U-seals; and (c) testing a full-scale bearing/seal package. Several operating parameters which have a radical effect on seal life were identified, and some promising designs and materials were tested.

  14. Conceptual design of a direct-contact natural-gas-fired downhole steam generator

    SciTech Connect

    Moreno, J.B.

    1982-06-01

    Conceptual designs are presented for three natural gas fueled, 1500 to 2000 psi, downhole steam generators: a 4 MMBtu/h unit sized for 7-inch casing, an 18.4 MMBtu/h unit sized for 7-inch casing, and an 18.4 MMBtu/h unit sized for 9-5/8-inch casing. Specifications for the support system for each system are outlined, considering both 3650-foot and 7000-foot well depths. Costs for major components and confidence levels for each design are estimated. Design philosophy and procedures are given in sufficient detail to enable extrapolation of or interpolation between the three designs.

  15. Downhole steam-generator study. Volume 1: Conception and feasibilty evaluation

    NASA Astrophysics Data System (ADS)

    1982-06-01

    A feasibility evaluation of a downhill steam generator was performed by the Rocketdyne Division of Rockwell International, under contract to Sandia National Laboratories, from September 1978 to September 1980. The study was conducted in four phases: (1) selection of a preliminary system design, (2) parametric analysis of the selected system, (3) experimental studies to demonstrate feasibility and develop design data, and (4) development of a final system design based on the parametric and experimental results. The feasibility of a low pressure combustion, indirect contact, downhole steam generator system was demonstrated. Key results from all phases of the study are presented herein.

  16. Direct-fired downhole steam generator - from design to field test

    SciTech Connect

    Schirmer, R.M.; Eson, R.L.

    1982-01-01

    A direct-fired downhole steam generator (DFDSG) has been developed which shows considerable promise for production of heavy oil. By carrying out the combustion process at high pressure, and then adding water, a mixture of carbon dioxide, nitrogen, and steam is charged directly into the heavy oil reservoir. This eliminates the need for expensive, and inefficient, stack scrubbers to remove sulfur dioxide, as well as sophisticated NO/sub x/ control techniques. The carbon dioxide created during the fuel burning process is absorbed by the heavy oil and increases its mobility without expending additional energy. 6 refs.

  17. Conceptual design of a direct-contact natural-gas-fired downhole steam generator

    NASA Astrophysics Data System (ADS)

    Moreno, J. B.

    1982-06-01

    Conceptual designs are presented for three natural gas fueled, 1500 to 2000 psi, downhole steam generators: a 4 MMBtu/h unit sized for 7-inch casing, an 18.4 MMBtu/h unit sized for 7-inch casing, and an 18.4 MMBtu/h unit sized for 9-5/8 inch casing. Specifications for the support systems for each system are outlined, considering both 3650-foot and 7000-foot well depths. Costs for major components and confidence levels for each design are estimated. Design philosophy and procedures are given in sufficient detail to enable extrapolation of or interpolation between the three designs.

  18. Analysis of Data from a Downhole Oil/Water Separator Field Trial in East Texas

    SciTech Connect

    Veil, John A.; Layne, Arthur Langhus

    2001-04-19

    Downhole oil/water separator (DOWS) technology is available to separate oil from produced water at the bottom of an oil well. Produced water can be injected directly to a disposal formation rather than lifting it to the surface, treating it there, and reinjecting it. Because of a lack of detailed performance data on DOWS systems, the U.S. Department of Energy (DOE) provided funding to secure DOWS performance data. A large U.S. oil and gas operator offered to share its data with Argonne National Laboratory. This report summarizes data from the DOWS installation in eastern Texas.

  19. The advantages of fluoropolymer encapsulation of the lines installed with continuous downhole injection systems

    SciTech Connect

    Goodson, J. ); Fox, B. )

    1989-01-01

    Dealing with corrosion has evolved from the early days of {und rust and replace} and now corrosion is effectively controlled by continuous chemical injection systems. A critical component of all continuous injection systems is the line. The line serves the purpose of transporting the chemical inhibitor downhole to the packer. Protecting the line during installation as well as its service life requires use of an encapsulation material to ensure integrity of the line and, therefore effectiveness of the entire system. Design criteria for the line and properties or encapsulation materials, including ECTFE fluoropolymer are discussed.

  20. Microchip amplifier for in vitro, in vivo, and automated whole cell patch-clamp recording.

    PubMed

    Harrison, Reid R; Kolb, Ilya; Kodandaramaiah, Suhasa B; Chubykin, Alexander A; Yang, Aimei; Bear, Mark F; Boyden, Edward S; Forest, Craig R

    2015-02-15

    Patch clamping is a gold-standard electrophysiology technique that has the temporal resolution and signal-to-noise ratio capable of reporting single ion channel currents, as well as electrical activity of excitable single cells. Despite its usefulness and decades of development, the amplifiers required for patch clamping are expensive and bulky. This has limited the scalability and throughput of patch clamping for single-ion channel and single-cell analyses. In this work, we have developed a custom patch-clamp amplifier microchip that can be fabricated using standard commercial silicon processes capable of performing both voltage- and current-clamp measurements. A key innovation is the use of nonlinear feedback elements in the voltage-clamp amplifier circuit to convert measured currents into logarithmically encoded voltages, thereby eliminating the need for large high-valued resistors, a factor that has limited previous attempts at integration. Benchtop characterization of the chip shows low levels of current noise [1.1 pA root mean square (rms) over 5 kHz] during voltage-clamp measurements and low levels of voltage noise (8.2 μV rms over 10 kHz) during current-clamp measurements. We demonstrate the ability of the chip to perform both current- and voltage-clamp measurement in vitro in HEK293FT cells and cultured neurons. We also demonstrate its ability to perform in vivo recordings as part of a robotic patch-clamping system. The performance of the patch-clamp amplifier microchip compares favorably with much larger commercial instrumentation, enabling benchtop commoditization, miniaturization, and scalable patch-clamp instrumentation. PMID:25429119

  1. Delaying cord clamping until ventilation onset improves cardiovascular function at birth in preterm lambs

    PubMed Central

    Bhatt, Sasmira; Alison, Beth J; Wallace, Euan M; Crossley, Kelly J; Gill, Andrew W; Kluckow, Martin; te Pas, Arjan B; Morley, Colin J; Polglase, Graeme R; Hooper, Stuart B

    2013-01-01

    Delayed cord clamping improves circulatory stability in preterm infants at birth, but the underlying physiology is unclear. We investigated the effects of umbilical cord clamping, before and after ventilation onset, on cardiovascular function at birth. Prenatal surgery was performed on lambs (123 days) to implant catheters into the pulmonary and carotid arteries and probes to measure pulmonary (PBF), carotid (CaBF) and ductus arteriosus blood flows. Lambs were delivered at 126 ± 1 days and: (1) the umbilical cord was clamped at delivery and ventilation was delayed for about 2 min (Clamp 1st; n = 6), and (2) umbilical cord clamping was delayed for 3–4 min, until after ventilation was established (Vent 1st; n = 6). All lambs were subsequently ventilated for 30 min. In Clamp 1st lambs, cord clamping rapidly (within four heartbeats), but transiently, increased pulmonary and carotid arterial pressures (by ∼30%) and CaBF (from 30.2 ± 5.6 to 40.1 ± 4.6 ml min−1 kg−1), which then decreased again within 30–60 s. Following ventilation onset, these parameters rapidly increased again. In Clamp 1st lambs, cord clamping reduced heart rate (by ∼40%) and right ventricular output (RVO; from 114.6 ± 14.4 to 38.8 ± 9.7 ml min−1 kg−1), which were restored by ventilation. In Vent 1st lambs, cord clamping reduced RVO from 153.5 ± 3.8 to 119.2 ± 10.6 ml min−1 kg−1, did not affect heart rates and resulted in stable blood flows and pressures during transition. Delaying cord clamping for 3–4 min until after ventilation is established improves cardiovascular function by increasing pulmonary blood flow before the cord is clamped. As a result, cardiac output remains stable, leading to a smoother cardiovascular transition throughout the early newborn period. PMID:23401615

  2. Fine Structure in 3C 120 and 3C 84. Ph.D. Thesis - Maryland Univ., 24 Aug. 1976

    NASA Technical Reports Server (NTRS)

    Hutton, L. K.

    1976-01-01

    Seven epochs of very long baseline radio interferometric observations of the Seyfert galaxies 3C 120 and 3C 84, at 3.8-cm wave length using stations at Westford, Massachusetts, Goldstone, California, Green Bank, West Virginia, and Onsala, Sweden, have been analyzed for source structure. An algorithm for reconstructing the brightness distribution of a spatially confined source from fringe amplitude and so called closure phase data has been developed and successfully applied to artificially generated test data and to data on the above mentioned sources. Over the two year time period of observation, 3C 120 was observed to consist of a double source showing apparent super relativistic expansion and separation velocities. The total flux changes comprising one outburst can be attributed to one of these components. 3C 84 showed much slower changes, evidently involving flux density changes in individual stationary components rather than relative motion.

  3. Outward currents in voltage-clamped rat sympathetic neurones.

    PubMed Central

    Galvan, M; Sedlmeir, C

    1984-01-01

    Outward membrane currents were studied in neurones of the isolated rat superior cervical ganglion by using a two-micro-electrode or single-micro-electrode voltage-clamp technique. Under current clamp, depolarization elicited electrotonic potentials that displayed marked outward rectification. From negative resting potentials (-70 mV) a short latency, short duration outward rectification was observed. From more positive potentials (-40 mV) a longer latency persistent outward rectification could be demonstrated. Under voltage clamp, four distinct outward currents were observed: a delayed rectifier (IK); a transient outward current (IA); a Ca2+-activated current (IC) and the M-current (IM). The maximum amplitude of IK, IA and IC was 1-2 orders of magnitude greater than IM. Depolarizing from -40 mV to potentials more positive than -20 mV co-activated IK and IC, producing a characteristic N-shaped current voltage curve with a minimum at about +80 mV. Superfusion with Mn2+-containing solutions reduced outward current at all voltages and abolished the N-characteristic; the remaining current (IK) slowly inactivated (tau greater than 1 s). Raising [K+]o from 6 to 36 mmol/l reversed outward tail currents observed in normal solution. Addition of tetraethylammonium ions (1-3 mmol/l) strongly reduced the amplitude of IK and IC. IA was characterized by very rapid activation at potentials more positive than -60 mV and by fast and complete inactivation at potentials in the activation range. The amplitude of IA was dependent on [K+]o and was reduced by external 4-aminopyridine (1-3 mmol/l). The activation appeared to depend on the nature and concentration of divalent cations present in the superfusate. It is concluded that the soma membrane of rat sympathetic neurones, like many other vertebrate and invertebrate neurones, contains multiple populations of K+ channels. The possible functions of these in the control of ganglion cell excitability are discussed. PMID:6097667

  4. Triplex-stabilizing properties of parallel clamps carrying LNA derivatives at the Hoogsteen strand.

    PubMed

    Alvira, Margarita; Eritja, Ramon

    2010-02-01

    DNA Parallel clamps with a polypurine strand linked to a polypyrimidine Hoogsteen strand containing locked nucleic acids bind their corresponding polypyrimidine targets with high affinity. PMID:20151386

  5. Kvn Source-Frequency Phase-Referencing Observation of 3c 66A and 3c 66B

    NASA Astrophysics Data System (ADS)

    Zhao, Guang-Yao; Jung, Taehyun; Dodson, Richard; Rioja, Maria; Sohn, Bong Won

    2015-09-01

    In this proceedings, preliminary results of the KVN Source-Frequency Phase-Referencing (SFPR) observation of 3C 66A and 3C 66B are presented. The motivation of this work is to measure the core-shift of these 2 sources and study the temporal evolution of the jet opacity. Two more sources were observed as secondary reference calibrators and each source was observed at 22, 43, and 86 GHz simultaneously. Our preliminary results show that after using the observations at the lower frequency to calibrate those at the higher frequency of the same source, the residual visibility phases for each source at the higher frequencies became more aligned, and the coherence time became much longer; also, the residual phases for different sources, within 10 degrees angular separations, follow similar trends. After reference to the nearby calibrator, the SFPRed maps were obtained as well as the astrometric measurements, i.e. the combined coreshift. The measurements were found to be affected by structural blending effects because of the large beamsize of KVN, but this can be corrected with higher resolution maps (e.g. KAVA maps). *%K Astrometry, radio continuum: galaxies, galaxies: active, galaxy: individual(3C 66A, 3C 66B), techniques: interferometric *%O 3C 66A, 3C 66B

  6. RXTE, VLBA, Optical, and Radio Monitoring of the Quasars 3C 279, PKS 1510--089, and 3C 273

    NASA Technical Reports Server (NTRS)

    Marscher, A. P.; Jorstad, S. G.; Aller, M. F.; McHardy, I. M.; Balonek, T. J.

    2001-01-01

    We are continuing our combined RXTE X-ray, VLBA imaging (at 43 GHz), optical (several observatories), and radio (University of Michigan Radio Astronomy Observatory) monitoring of the quasars 3C 279 and PKS 1510-089, and have started similar monitoring of 3C 273. X-ray flares in 3C 279 and PKS 1510-089 are associated with ejections of superluminal components. In addition, there is a close connection between the optical and X-ray variability of 3C 279. There is a strong correlation between the 14.5 GHz and X-ray variability of PKS 1510-089 in 1997 and 1998 (with the radio leading the X-ray) that becomes weaker in subsequent years. X-ray fluctuations occur on a variety of timescales in 3C 273, with a major prolonged outburst in mid-2001. The lead author will discuss the correlations in terms of inverse Compton models for the X-ray emission coupled with synchrotron models for the lower-frequency radiation. Synchrotron self-Compton models can explain the "reverse" time lag in PKS 1510-089 is well as the variable correlation between the X-ray variations and those at lower frequencies in this object and in 3C 279.

  7. Downhole steam-generator study. Volume I. Conception and feasibility evaluation. Final report, September 1978-September 1980

    SciTech Connect

    Not Available

    1982-06-01

    A feasibility evaluation of a downhole steam generator was performed by the Rocketdyne Division of Rockwell International, under contract to Sandia National Laboratories, from September 1978 to September 1980. The study was conducted in four phases: (1) selection of a preliminary system design, (2) parametric analysis of the selected system, (3) experimental studies to demonstrate feasibility and develop design data, and (4) development of a final system design based on the parametric and experimental results. The feasibility of a low pressure combustion, indirect contact, downhole steam generator system was demonstrated. Key results from all phases of the study are presented herein.

  8. Self-clamping arc light reflector for welding torch

    NASA Technical Reports Server (NTRS)

    Gordon, Stephen S. (Inventor)

    1987-01-01

    This invention is directed to a coaxial extending metal mirror reflector attached to the electrode housing or gas cup on a welding torch. An electric welding torch with an internal viewing system for robotic welding is provded with an annular arc light reflector to reflect light from the arc back onto the workpiece. The reflector has a vertical split or gap in its surrounding wall to permit the adjacent wall ends forming the split to be sprung open slightly to permit the reflector to be removed or slipped onto the torch housing or gas cup. The upper opening of the reflector is slightly smaller than the torch housing or gas cup and therefore, when placed on the torch housing or gas cup has that springiness to cause it to clamp tightly on the housing or gas cup. The split or gap also serves to permit the feed of weld wire through to the weld area,

  9. Non-Linear Vibration Characteristics of Clamped Laminated Shallow Shells

    NASA Astrophysics Data System (ADS)

    ABE, A.; KOBAYASHI, Y.; YAMADA, G.

    2000-07-01

    This paper examines non-linear free vibration characteristics of first and second vibration modes of laminated shallow shells with rigidly clamped edges. Non-linear equations of motion for the shells based on the first order shear deformation and classical shell theories are derived by means of Hamilton's principle. We apply Galerkin's procedure to the equations of motion in which eigenvectors for first and second modes of linear vibration obtained by the Ritz method are employed as trial functions. Then simultaneous non-linear ordinary differential equations are derived in terms of amplitudes of the first and second vibration modes. Backbone curves for the first and second vibration modes are solved numerically by the Gauss-Legendre integration method and the shooting method respectively. The effects of lamination sequences and transverse shear deformation on the behavior are discussed. It is also shown that the motion of the first vibration mode affects the response for the second vibration mode.

  10. Simple clamp pressure cell up to 30 kbar

    NASA Astrophysics Data System (ADS)

    Fujiwara, H.; Kadomatsu, H.; Tohma, K.

    1980-10-01

    A design of simple clamp type pressure apparatus utilized for measurements of magnetic susceptibility and electrical resistivity at low temperatures is presented. The cell consists of a WC piston and Be-Cu cylinder which was autofrettage-processed, and the sample cavity consists of a teflon bucket and an electrode plug. In a temperature range from 300 to 77 K, pressure was determined by a manganin gage calibrated by Bi I-II transition pressure at room temperature; the temperature dependence of pressure coefficient of manganin resistance was taken into account. As a result, the cell was capable of generating hydrostatic pressures up to 30 kbar at room temperature and at least up to 25 kbar at 4.2 K.

  11. Vibration of clamped right triangular thin plates: Accurate simplified solutions

    NASA Astrophysics Data System (ADS)

    Saliba, H. T.

    1994-12-01

    Use of the superposition techniques in the free-vibration analyses of thin plates, as they were first introduced by Gorman, has provided simple and effective solutions to a vast number of rectangular plate problems. The method has also been extended to nonrectangular plates such as triangular and trapezoidal plates. However, serious difficulties were encountered in some of these analyses. These difficulties were discussed and obviated in Salibra, 1990. This reference, however, dealt only with simple support conditions, leading to a simple, highly accurate, and very economical solution to the free-vibration problem of simply supported right angle triangular plates. The purpose of this Note is to show that the modified superposition method of Salibra, 1990 is also applicable to clamped-edge conditions. This is accomplished through the application of this method to the title problem.

  12. Polarization-maintaining amplifier based on 3C fiber structures

    NASA Astrophysics Data System (ADS)

    Enokidani, Jun; Ito, Rumi; Sakurai, Tsutomu; Shin, Sumida; Tei, Kazuyoku

    2015-03-01

    Chirally-Coupled-Core (3C) fiber structure can preserve a single mode quality and even a linear polarization for a large core size. A principal advantage of fiber laser is its compatibility with monolithic integration and robust system. But so far, devices such as a combiner using the 3C fibers have not been reported. Here we report the first demonstration of such monolithic amplifier structure which contains an active fiber and a combiner based on 3C fibers. A single-stage amplifier is seeded by an EO Q-switched micro-laser and pumped by two high power fiber pigtailed 976-nm laser diodes via an in-house fabricated (2 + 1) × 1 pump signal combiner. The active fiber is based on a 3-m-long, 3C Yb-doped fiber (33 μm/250 μm core/cladding diameter with 0.06/0.46 NA). The amplifier demonstrates scaling up to 30W average power and 150 kW peak power in 0.3mJ, 2ns pulses. The beam profiles and beam qualities were characterized as its output power was varied up to 30W. The beam profile was maintained at a high beam quality of around M2=1.2. The spectral properties of the 3C fiber were also characterized as its output peak power was varied.

  13. Whole-cell Patch-clamp Recordings in Brain Slices.

    PubMed

    Segev, Amir; Garcia-Oscos, Francisco; Kourrich, Saïd

    2016-01-01

    Whole-cell patch-clamp recording is an electrophysiological technique that allows the study of the electrical properties of a substantial part of the neuron. In this configuration, the micropipette is in tight contact with the cell membrane, which prevents current leakage and thereby provides more accurate ionic current measurements than the previously used intracellular sharp electrode recording method. Classically, whole-cell recording can be performed on neurons in various types of preparations, including cell culture models, dissociated neurons, neurons in brain slices, and in intact anesthetized or awake animals. In summary, this technique has immensely contributed to the understanding of passive and active biophysical properties of excitable cells. A major advantage of this technique is that it provides information on how specific manipulations (e.g., pharmacological, experimenter-induced plasticity) may alter specific neuronal functions or channels in real-time. Additionally, significant opening of the plasma membrane allows the internal pipette solution to freely diffuse into the cytoplasm, providing means for introducing drugs, e.g., agonists or antagonists of specific intracellular proteins, and manipulating these targets without altering their functions in neighboring cells. This article will focus on whole-cell recording performed on neurons in brain slices, a preparation that has the advantage of recording neurons in relatively well preserved brain circuits, i.e., in a physiologically relevant context. In particular, when combined with appropriate pharmacology, this technique is a powerful tool allowing identification of specific neuroadaptations that occurred following any type of experiences, such as learning, exposure to drugs of abuse, and stress. In summary, whole-cell patch-clamp recordings in brain slices provide means to measure in ex vivo preparation long-lasting changes in neuronal functions that have developed in intact awake animals

  14. The human dynamic clamp as a paradigm for social interaction

    PubMed Central

    Dumas, Guillaume; de Guzman, Gonzalo C.; Tognoli, Emmanuelle; Kelso, J. A. Scott

    2014-01-01

    Social neuroscience has called for new experimental paradigms aimed toward real-time interactions. A distinctive feature of interactions is mutual information exchange: One member of a pair changes in response to the other while simultaneously producing actions that alter the other. Combining mathematical and neurophysiological methods, we introduce a paradigm called the human dynamic clamp (HDC), to directly manipulate the interaction or coupling between a human and a surrogate constructed to behave like a human. Inspired by the dynamic clamp used so productively in cellular neuroscience, the HDC allows a person to interact in real time with a virtual partner itself driven by well-established models of coordination dynamics. People coordinate hand movements with the visually observed movements of a virtual hand, the parameters of which depend on input from the subject’s own movements. We demonstrate that HDC can be extended to cover a broad repertoire of human behavior, including rhythmic and discrete movements, adaptation to changes of pacing, and behavioral skill learning as specified by a virtual “teacher.” We propose HDC as a general paradigm, best implemented when empirically verified theoretical or mathematical models have been developed in a particular scientific field. The HDC paradigm is powerful because it provides an opportunity to explore parameter ranges and perturbations that are not easily accessible in ordinary human interactions. The HDC not only enables to test the veracity of theoretical models, it also illuminates features that are not always apparent in real-time human social interactions and the brain correlates thereof. PMID:25114256

  15. Analysis of impactor residues in tray clamps from the Long Duration Exposure Facility. Part 1: Clamps from Bay A of the satellite

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael E.; Bernhard, Ronald P.

    1993-01-01

    The Long Duration Exposure Facility (LDEF) was placed in low Earth orbit (LEO) in 1984 and was recovered 5.7 years later. The LDEF was host to several individual experiments that were specifically designed to characterize critical aspects of meteoroid and debris environment in LEO. It was realized from the beginning, however, that the most efficient use of the satellite would be to examine the entire surface of the Earth for impact features. In this regard, particular interest has centered on common exposed materials that faced in all LDEF pointing directions. Among the most important of these materials is the tray clamps. Therefore, in an effort to understand the nature of particulates in LEO and their effects on spacecraft hardware better, we are analyzing residues found in impact features on LDEF tray clamp surfaces. This catalog presents all data from clamps from Bay A of the LDEF. Subsequent catalogs will include clamps from succeeding bays of the satellite.

  16. Subsurface exploration using bucket auger borings and down-hole geologic inspection

    SciTech Connect

    Scullin, C.M. )

    1994-03-01

    The down-hole geologic inspection of 24 in. bucket auger borings has been a hands-on technique for collecting valuable geologic structural and lithologic detail in southern California investigations for over 35 yr. Although it has been used for all types of investigations for hillside urban development, it is of particular benefit in landslide investigations and evaluations. The benefits of down-hole geologic inspection during detailed mapping of large landslide complexes with multiple slide planes are discussed in this paper. Many of the geotechnical investigations of these massive landslide complexes have been very limited in their determinations of accurate landslide parameters and very deficient in proper engineering analysis while based upon this limited data. This has resulted in many cases where the geotechnical consultant erroneously concludes that ancient landslides don't move and it is all right to build upon them, even though they have neither justified the landslide parameters, nor the slope stability or safety. Because this author and the many consultants contacted during the preparation of this paper were not aware of other publications regarding this method of collecting detailed geologic data, this author included the safety considerations, safety equipment, the cost and the Cal OSHA requirements for entering exploration shafts.

  17. Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma

    SciTech Connect

    J. Ford Brett; Robert V. Westermark

    2000-09-30

    This Technical Quarterly Report is for the reporting period July 1, 2000 to September 30, 2000. The report provides details of the work done on the project entitled ''Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma''. The project is divided into nine separate tasks. Since this is the first Quarterly report, much of the work done is of a preliminary nature. Several of the tasks are being worked on simultaneously, while other tasks are dependent on earlier tasks being completed. The selection of the pilot test area has been completed. The drilling of the test well is waiting on rig availability. Phillips has begun sonic core testing of offset cores, waiting on the core from the well to be drilled. Design work is progressing for the tool, which will be built to fit the test well. Installation of monitoring equipment and the downhole vibration tool will occur after the well is drilled. Technical transfer efforts have begun with the submission of an abstract for a technical paper for the Oklahoma City Society of Petroleum Engineers meeting in March 2001.

  18. Advanced Data Communications for Downhole Data Logging and Control Applications in the Oil Industry

    NASA Astrophysics Data System (ADS)

    Spracklen, C. T.; Aslam, Tariq

    2013-12-01

    We present details of 'Mercury', a high-speed downhole communications system that utilizes the (metallic) wall of a gas or oil pipeline or a drill 'string' as the communications 'channel' to control or monitor equipment or sensors used in the oil industry. Conventional downhole communication systems typically use 'mud pulse' telemetry for 'Measurement While Drilling' (MWD) operations. Current mud pulse telemetry technology offers bandwidths of up to 40 bit/s. However the data rate drops with increasing length of the wellbore and is typically as low as 1.5 bit/s - 3.0 bit/s at a depth of 35,000 ft. - 40,000 ft. The system described, by contrast, offers data rates of several megabits per second over distances of many kilometres and uses Orthogonal Frequency Division Multiplexing (OFDM) coupled with Wideband Frequency Division Multiple Access (W-CDMA). This paper presents details of our system; results of several trials undertaken on actual gas pipelines in the UK will be presented at the Conference.

  19. Fabrication, assembly, bench and drilling tests of two prototype downhole pneumatic turbine motors: Final technical report

    SciTech Connect

    Bookwalter, R.; Duettra, P.D.; Johnson, P.; Lyons, W.C.; Miska, S.

    1987-04-01

    The first and second prototype downhole pneumatic turbine motors have been fabricated, assembled and tested. All bench tests showed that the motor will produce horsepower and bit speeds approximating the predicted values. Specifically, the downhole pneumatic turbine motor produced approximately 50 horsepower at 100 rpm, while being supplied with about 3600 SCFM of compressed air. The first prototype was used in a drilling test from a depth of 389 feet to a depth of 789 feet in the Kirtland formation. This first prototype motor drilled at a rate exceeding 180 ft/hr, utilizing only 3000 SCFM of compressed air. High temperature tests (at approximately 460/sup 0/F) were carried out on the thrust assembly and the gearboxes for the two prototypes. These components operated successfully at these temperatures. Although the bench and drilling tests were successful, the tests revealed design changes that should be made before drilling tests are carried out in geothermal boreholes at the Geysers area, near Santa Rosa, California.

  20. Element for use in an inductive coupler for downhole drilling components

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David S.; Dahlgren, Scott; Fox, Joe; Sneddon, Cameron

    2006-08-29

    The present invention includes an element for use in an inductive coupler in a downhole component. The element includes a plurality of ductile, generally U-shaped leaves that are electrically conductive. The leaves are less than about 0.0625" thick and are separated by an electrically insulating material. These leaves are aligned so as to form a generally circular trough. The invention also includes an inductive coupler for use in downhole components, the inductive coupler including an annular housing having a recess with a magnetically conductive, electrically insulating (MCEI) element disposed in the recess. The MCEI element includes a plurality of segments where each segment further includes a plurality of ductile, generally U-shaped electrically conductive leaves. Each leaf is less than about 0.0625" thick and separated from the otherwise adjacent leaves by electrically insulating material. The segments and leaves are aligned so as to form a generally circular trough. The inductive coupler further includes an insulated conductor disposed within the generally circular trough. A polymer fills spaces between otherwise adjacent segments, the annular housing, insulated conductor, and further fills the circular trough.

  1. Downhole measurements and fluid chemistry of a castle rock steam well, the Geysers, Lake County, California

    USGS Publications Warehouse

    Truesdell, A.H.; Nathenson, M.; Frye, G.A.

    1981-01-01

    Wellbore and reservoir processes in a steam well in the Castle Rock field of The Geysers have been studied by means of down-hole pressure and temperature measurements and analyses of ejected water and steam produced under bleed and full flow. Down-hole measurements show that below a vapor zone there is liquid water in the well in pressure equilibrium with reservoir steam at a depth of 2290 m. The progressive decreases, from 1973 to 1977, of pressure and temperature in the vapor zone indicate that wellbore heat loss is high enough to condense a large fraction of the steam inflow. The chemical composition of water ejected from the well is consistent with an origin from wellbore condensation of steam. Calculations using the differences in gas and isotopic compositions between bleed and full-flow steam show that about half of the full-flow steam originated as liquid water in the reservoir and that about 30% of the steam entering the well under bleed was condensed in the wellbore and drained downward. Heat loss calculations are also consistent with this amount of condensation. ?? 1981.

  2. Downhole measurements in the AND-1B borehole, ANDRILL McMurdo Ice Shelf Project, Antarctica

    USGS Publications Warehouse

    Morin, R.; Williams, T.; Henrys, S.; Crosby, T.; Hansaraj, D.

    2007-01-01

    A comprehensive set of downhole measurements was collected in the AND-1B drillhole as part of the on-ice scientific programme defined for the McMurdo Ice Shelf (MIS) Project. Geophysical logs were recorded over two operation phases and consisted of calliper, temperature, fluid conductivity, induction resistivity, magnetic susceptibility, natural gamma activity, acoustic televiewer, borehole deviation, and dipmeter. In addition, two standard vertical seismic profiles (VSP) and one walk-away VSP were obtained. Radioactive logs (porosity and density) were not run because of unstable borehole conditions. Although the total depth of the hole is 1285 metres below seafloor (mbsf), the depth range for in situ measurements was limited by the length of the wireline (1018 mbsf) and by the nullification of some geophysical logs due to the presence of steel casing. A depth correction was derived to account for systematic discrepancies in depth between downhole measurements and cores; consequently, log responses can be directly compared to core properties. The resulting data are amenable to studies of cyclicity and climate, heat flux and fluid flow, and stricture and stress. When integrated with physical properties and fractures measured on the core, this information should play a significant role in addressing many of the scientific objectives of the ANDRILL programme.

  3. Energetics and structural stability of Cs3C60

    SciTech Connect

    Saito, Susumu; Umemoto, Koichiro; Louie, Steven G.; Cohen, MarvinL.

    2003-12-15

    Using the ab initio pseudo potential total-energy method and the density-functional theory, we study the energetics of face-centered-cubic Cs3C60 which is a material of great interest as a possible high transition-temperature superconductor. At the optimized lattice constant the volume per C60 is found to be smaller than the most stable hexagon-coordination A15 phase, while the total energy of the fcc phase is about 0.9 eV higher than the A15 phase. These results indicate that a low-temperature and high-pressure synthesis method might be a possible way to produce the fcc Cs3C60 phase. In addition, it is also found that the A15 Cs3C60 should show a phase transformation from a hexagon-coordination phase to a pentagon-coordination phase under hydrostatic pressure.

  4. Graphene/3C-SiC Hybrid Nanolaminate.

    PubMed

    Zhuang, Hao; Yang, Bing; Heuser, Steffen; Huang, Nan; Fu, Haiyuan; Jiang, Xin

    2015-12-30

    In this work, we demonstrate a one-step approach to create graphene/3C-SiC nanolaminate structure using microwave plasma chemical vapor deposition technique. Layer-by-layer arrangement of thin 3C-SiC layers and graphene sheets is obtained with the thicknesses of the individual 3C-SiC layers and graphene sheets being 5-10 nm and 2-5 nm, respectively. An intimate contact between 3C-SiC and the graphene sheets is achieved and the nanolaminate film shows a high room temperature conductivity of 96.1 S/cm. A dedicated structural analysis of the nanolaminates by means of high-resolution transmission electron microscopy (HRTEM) reveals that the growth of the nanolaminates follows an iterative process: preferential graphene nucleation around the planar defects at the central region of the SiC layer, leading to the "splitting" of the SiC layer; and the thickening of the SiC layer after being "split". A growth mechanism based on both kinetics and thermodynamics is proposed. Following the proposed mechanism, it is possible to control the layer thickness of the graphene/3C-SiC hybrid nanolaminate by manipulating the carbon concentration in the gas phase, which is further experimentally verified. The high electrical conductivity, large surface area porous structure, feasible integration on different substrates (metal, Mo; semiconductor, Si and 2H-SiC; insulator, diamond) of the graphene/3C-SiC hybrid nanolaminate as well as other unprecedented advantages of the nanolaminate structure make it very promising for applications in mechanical, energy, and sensor-related areas. PMID:26650041

  5. Antibacterial Activity of Ti3C2Tx MXene.

    PubMed

    Rasool, Kashif; Helal, Mohamed; Ali, Adnan; Ren, Chang E; Gogotsi, Yury; Mahmoud, Khaled A

    2016-03-22

    MXenes are a family of atomically thin, two-dimensional (2D) transition metal carbides and carbonitrides with many attractive properties. Two-dimensional Ti3C2Tx (MXene) has been recently explored for applications in water desalination/purification membranes. A major success indicator for any water treatment membrane is the resistance to biofouling. To validate this and to understand better the health and environmental impacts of the new 2D carbides, we investigated the antibacterial properties of single- and few-layer Ti3C2Tx MXene flakes in colloidal solution. The antibacterial properties of Ti3C2Tx were tested against Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) by using bacterial growth curves based on optical densities (OD) and colonies growth on agar nutritive plates. Ti3C2Tx shows a higher antibacterial efficiency toward both Gram-negative E. coli and Gram-positive B. subtilis compared with graphene oxide (GO), which has been widely reported as an antibacterial agent. Concentration dependent antibacterial activity was observed and more than 98% bacterial cell viability loss was found at 200 μg/mL Ti3C2Tx for both bacterial cells within 4 h of exposure, as confirmed by colony forming unit (CFU) and regrowth curve. Antibacterial mechanism investigation by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) coupled with lactate dehydrogenase (LDH) release assay indicated the damage to the cell membrane, which resulted in release of cytoplasmic materials from the bacterial cells. Reactive oxygen species (ROS) dependent and independent stress induction by Ti3C2Tx was investigated in two separate abiotic assays. MXenes are expected to be resistant to biofouling and offer bactericidal properties. PMID:26909865

  6. Biglycan is a novel binding partner of fibroblast growth factor receptor 3c (FGFR3c) in the human testis.

    PubMed

    Winge, S B; Nielsen, J; Jørgensen, A; Owczarek, S; Ewen, K A; Nielsen, J E; Juul, A; Berezin, V; Rajpert-De Meyts, E

    2015-01-01

    Regulation of spermatogonial maintenance in the human testis is currently not well understood. One pathway suggested to be involved is activated by fibroblast growth factor receptor 3 (FGFR3), which is expressed in a subset of spermatogonia. FGFR3-activating mutations have been identified in spermatocytic seminoma, thought to originate from clonal expansion of spermatogonia. In this study we aimed to characterize potential binding partners of FGFR3, and specifically its mesenchymal "c" splice isoform, in human spermatogonia. Based on expression patterns and homology to the binding site, we identified FGF1, FGF2, and FGF9 as the best candidates for natural ligands of FGFR3c in the testis. In addition, we screened non-FGF proteins and found that a proteoglycan biglycan (BGN) contains a sequence homologous to the FGFR3c binding site on FGF1, and is expressed in peritubular cells adjacent to FGFR3-expressing spermatogonia. Experiments in a cell-free system confirmed that BGN binds to FGFR3c and FGF1. In conclusion, our findings further clarify the complex regulation of FGFR3c in the human testis. We postulate that BGN is a factor secreted by peritubular cells to modulate FGFR3c signaling and thus contributes to the regulation of spermatogonial maintenance. PMID:25260943

  7. A comparison of the performance and application differences between manual and automated patch-clamp techniques.

    PubMed

    Yajuan, Xiao; Xin, Liang; Zhiyuan, Li

    2012-01-01

    The patch clamp technique is commonly used in electrophysiological experiments and offers direct insight into ion channel properties through the characterization of ion channel activity. This technique can be used to elucidate the interaction between a drug and a specific ion channel at different conformational states to understand the ion channel modulators' mechanisms. The patch clamp technique is regarded as a gold standard for ion channel research; however, it suffers from low throughput and high personnel costs. In the last decade, the development of several automated electrophysiology platforms has greatly increased the screen throughput of whole cell electrophysiological recordings. New advancements in the automated patch clamp systems have aimed to provide high data quality, high content, and high throughput. However, due to the limitations noted above, automated patch clamp systems are not capable of replacing manual patch clamp systems in ion channel research. While automated patch clamp systems are useful for screening large amounts of compounds in cell lines that stably express high levels of ion channels, the manual patch clamp technique is still necessary for studying ion channel properties in some research areas and for specific cell types, including primary cells that have mixed cell types and differentiated cells that derive from induced pluripotent stem cells (iPSCs) or embryonic stem cells (ESCs). Therefore, further improvements in flexibility with regard to cell types and data quality will broaden the applications of the automated patch clamp systems in both academia and industry. PMID:23346269

  8. 30 CFR 75.605 - Clamping of trailing cables to equipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Clamping of trailing cables to equipment. 75.605 Section 75.605 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.605 Clamping of trailing cables to equipment....

  9. 30 CFR 75.605 - Clamping of trailing cables to equipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Clamping of trailing cables to equipment. 75.605 Section 75.605 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.605 Clamping of trailing cables to equipment....

  10. 30 CFR 75.605 - Clamping of trailing cables to equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clamping of trailing cables to equipment. 75.605 Section 75.605 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.605 Clamping of trailing cables to equipment....

  11. 30 CFR 75.605 - Clamping of trailing cables to equipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Clamping of trailing cables to equipment. 75.605 Section 75.605 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.605 Clamping of trailing cables to equipment....

  12. Structural insight into β-Clamp and its interaction with DNA Ligase in Helicobacter pylori.

    PubMed

    Pandey, Preeti; Tarique, Khaja Faisal; Mazumder, Mohit; Rehman, Syed Arif Abdul; Kumari, Nilima; Gourinath, Samudrala

    2016-01-01

    Helicobacter pylori, a gram-negative and microaerophilic bacterium, is the major cause of chronic gastritis, gastric ulcers and gastric cancer. Owing to its central role, DNA replication machinery has emerged as a prime target for the development of antimicrobial drugs. Here, we report 2Å structure of β-clamp from H. pylori (Hpβ-clamp), which is one of the critical components of DNA polymerase III. Despite of similarity in the overall fold of eubacterial β-clamp structures, some distinct features in DNA interacting loops exists that have not been reported previously. The in silico prediction identified the potential binders of β-clamp such as alpha subunit of DNA pol III and DNA ligase with identification of β-clamp binding regions in them and validated by SPR studies. Hpβ-clamp interacts with DNA ligase in micromolar binding affinity. Moreover, we have successfully determined the co-crystal structure of β-clamp with peptide from DNA ligase (not reported earlier in prokaryotes) revealing the region from ligase that interacts with β-clamp. PMID:27499105

  13. Structural insight into β-Clamp and its interaction with DNA Ligase in Helicobacter pylori

    PubMed Central

    Pandey, Preeti; Tarique, Khaja Faisal; Mazumder, Mohit; Rehman, Syed Arif Abdul; kumari, Nilima; Gourinath, Samudrala

    2016-01-01

    Helicobacter pylori, a gram-negative and microaerophilic bacterium, is the major cause of chronic gastritis, gastric ulcers and gastric cancer. Owing to its central role, DNA replication machinery has emerged as a prime target for the development of antimicrobial drugs. Here, we report 2Å structure of β-clamp from H. pylori (Hpβ-clamp), which is one of the critical components of DNA polymerase III. Despite of similarity in the overall fold of eubacterial β-clamp structures, some distinct features in DNA interacting loops exists that have not been reported previously. The in silico prediction identified the potential binders of β-clamp such as alpha subunit of DNA pol III and DNA ligase with identification of β-clamp binding regions in them and validated by SPR studies. Hpβ-clamp interacts with DNA ligase in micromolar binding affinity. Moreover, we have successfully determined the co-crystal structure of β-clamp with peptide from DNA ligase (not reported earlier in prokaryotes) revealing the region from ligase that interacts with β-clamp. PMID:27499105

  14. Revisiting correlations between broad-line and jet emission variations for AGNs: 3C 120 and 3C 273

    NASA Astrophysics Data System (ADS)

    Liu, H. T.; Bai, J. M.; Feng, H. C.; Li, S. K.

    2015-06-01

    We restudy the issue of cross-correlations between broad-line and jet emission variations, and aim to locate the position of a radio (and gamma-ray) emitting region in a jet of active galactic nuclei. Considering the radial profiles of the radius and number density of clouds in a spherical broad-line region (BLR), we derive new formulae connecting the jet-emitting position Rjet to the time lag τob between broad-line and jet emission variations, and the BLR radius. Also, formulae are derived for a disc-like BLR and a spherical shell BLR. The model-independent flux randomization/random subset selection method is used to estimate τob. For 3C 120, positive lags of about 0.3 yr are found between the 15 GHz emission and the Hβ, Hγ and He II λ4686 lines, including broad-line data in a newly published paper, indicating that the line variations lead the 15 GHz ones. Each of the broad-line light curves corresponds to a radio outburst. Rjet = 1.1-1.5 parsec (pc) is obtained for 3C 120. For 3C 273, a common feature of negative time lags is found in the cross-correlation functions between light curves of radio emission and the Balmer lines, as well as Lyα λ1216 and C IV λ1549 lines. Rjet = 1.0-2.6 pc is obtained for 3C 273. The estimated Rjet is comparable for 3C 120 and 3C 273, and the gamma-ray-emitting positions will be within ˜1-3 pc from the central engines. Comparisons show that the cloud number density and radius radial distributions and the BLR structures have only negligible effects on Rjet.

  15. Microwave Radiometer – 3 Channel (MWR3C) Handbook

    SciTech Connect

    Cadeddu, MP

    2012-05-04

    The microwave radiometer 3-channel (MWR3C) provides time-series measurements of brightness temperatures from three channels centered at 23.834, 30, and 89 GHz. These three channels are sensitive to the presence of liquid water and precipitable water vapor.

  16. The 3C support: A survivable alternative to wood cribbing

    SciTech Connect

    Frederick, J.

    1995-10-01

    Wood cribbing has historically been a somewhat dependable and low cost method of providing mine roof support. In high stress conditions, such as longwall tailgates, the wood crib does not always survive. Failure of tailgate cribs can block travelways, restrict ventilation and force costly time-consuming rehabilitation. At least in the Western United States, wood cribbing is no longer the answer to many roof support problems. Western mines are being forced to find alternatives to wood cribbing. This is due to the escalating cost, questionable availability and dubious quality of available wood supplies. The Corrugated Confined Core mine roof Support (3C Support) was developed to survive the extreme ground control conditions of a longwall tailgate. The 3C Support testing has shown ultimate strengths exceeding 2,000,000 lbs and a yield range over 48-inches. Standard wood cribs, constructed from Western United States softwood, were also tested. The wood cribs had ultimate strengths up to 237,000 lbs and a yield range up to 27-inches. Underground testing of the 3C Support in longwall tailgates at Southern Utah Fuel Company (SUFCO) was also conducted. This testing and installation of over 5000 3C Supports have demonstrated the following advantages: (1) lower installed cost; (2) 55 percent reduction in cribbing manpower requirements; (3) improved yield and ultimate strength characteristics; (4) much improved tailgate roof support survivability; (5) virtually eliminates blocked tailgates; (6) improved safety; (7) reduced flammable material; (8) improved ventilation; and (9) environmentally friendly.

  17. Low Frequency Radio Observations of 3C 129

    NASA Astrophysics Data System (ADS)

    Lane, W. M.; Harris, D. E.; Ensslin, T. A.; Kassim, N. E.; Perley, R. A.

    2001-12-01

    We present a wide-field map of the radio galaxy 3C 129 and its companion galaxy 3C 129.1 at λ = 90 cm. Both galaxies are part of an X-ray identified cluster at z=0.021, which has been excluded from most optical studies because it lies in the galactic plane. 3C 129 is a narrow-angle-tail (NAT) source with a plume-like double-tail extending nearly 30' at a wavelength of 90cm. We see a distinct steep-spectrum feature near its head, extending in a direction perpendicular to the radio tails. We propose is that this `crosspiece' might consist of fossil radio plasma, which has been re-energized by the compression of the bow shock wave of the supersonically moving galaxy 3C 129. One possible origin of the fossil radio plasma could be the tail of a nearby head-tail radio galaxy, and we discuss the implications of this scenario. WML is a National Research Council Postdoctoral Fellow. Basic research in astronomy at the Naval Research Laboratory is funded by the Office of Naval Research. DEH acknowledges support from NASA grant GO1-2135A.

  18. The linear polarization of 3C 345 in the ultraviolet

    NASA Technical Reports Server (NTRS)

    Dolan, Joseph F.; Boyd, Patricia T.; Wolinski, Karen G.; Smith, Paul S.; Impey, C. D.; Bless, Robert C.; Nelson, M. J.; Percival, J. W.; Taylor, M. J.; Elliot, J. L.

    1994-01-01

    The linear polarization of 3C 345, a superluminal radio source and OVV quasar, was observed in two bandpasses in the ultraviolet (centered at 2160 A and 2770 A) in 1993 April using the High Speed Photometer on the Hubble Space Telescope. The quasar is significantly polarized in the UV (p greater than 5%). Ground-based polarimetry was obtained 11 days later, but a difference in the position angle between the observations in the visible and those in the UV indicate that the magnitude of the polarization of 3C 345 may have changed over that time. If the two observation sets represent the same state of spectral polarization, then the large UV flux implies that either the polarization of the synchrotron continuum must stop decreasing in the UV, or that there is an additional source of polarized flux in the ultraviolet. Only if the UV observations represent a spectral polarization state with the same position angle in the visible seen previously in 3C 345 can the polarized flux be represented by a single power law consistent with the three-component model of Smith et al. This model consists of a polarized synchrotron component, an unpolarized component from the broad-line region, and an unpolarized component attributed to thermal radiation from an optically thick accretion disk. Additional simultaneous polarimetry in the UV and visible will be required to further constrain models of the continuum emission processes in 3C 345 and determine if the UV polarized flux is synchrotron in origin.

  19. Program for the Improvement of Downhole Drilling-Motor Bearings and Seals. Phase III, Part 2: final report

    SciTech Connect

    Not Available

    1980-03-01

    Six months of activity to improve downhole drilling-motor bearings and seals for geothermal applications are reported. The following are covered: seal testing and evaluation, bearing-seal package testing and evaluation, lubricant testing and evaluation, and program status, plans and schedule. (MHR)

  20. Note: High-efficiency energy harvester using double-clamped piezoelectric beams

    SciTech Connect

    Zheng, Yingmei; Wu, Xuan; Parmar, Mitesh; Lee, Dong-weon

    2014-02-15

    In this study, an improvement in energy conversion efficiency has been reported, which is realized by using a double-clamped piezoelectric beam, based on uniaxial stretching strain. The buckling mechanism is applied to maximize axial stress in the double-clamped beam. The voltage generated by using the double-clamped piezoelectric beam is higher than that generated by using other conventional structures, such as bending cantilevers coated/sandwiched with piezoelectric film, which is proven both theoretically and experimentally. The power generation efficiency is enhanced by further optimizing the double-clamped structure. The optimized high-efficiency energy harvester utilizing double-clamped piezoelectric beams generates a peak output power of 80 μW, under an acceleration of 0.1g.

  1. Clamp ultrastructure of the basal monogenean Chimaericola leptogaster (Leuckart, 1830) (Polyopisthocotylea: Chimaericolidae).

    PubMed

    Poddubnaya, Larisa G; Hemmingsen, Willy; Gibson, David I

    2014-11-01

    The ultrastructure of the haptoral clamps of the chimaericolid monogenean Chimaericola leptogaster, a basal polyopisthocotylean from the gills of a holocephalan fish, is described. These clamps are characterized by the presence of two muscle blocks interrupted mid-anteriorly and mid-posteriorly and different kinds of hard structures: a single median and paired lateral sclerites embedded in the clamp wall; six spine-like structures directed towards the clamp lumen; and electron dense surface structures along the internal surface of the anterior clamp lips and along the luminal surface of the tegument of the clamp lumen. The lateral sclerites are situated deep within muscular tissue and are closely bounded by radial myofibrils, possessing a uniform electron dense matrix within which are hollow areas of different sizes. The median sclerite occupies an area between the clamp wall myofibrils and the luminal epithelium, is surrounded by a basement lamina and is composed of a heterogeneous matrix comprising two different morphological layers related to variations in the type and concentration of fibrils. Four of the spine-like structures are extensions of the margins of the two spindle-like muscle blocks in the clamps, i.e. the two anterior and two posterior structures, and the two others are situated at the lateral constrictions of the left and right muscle blocks. The electron dense surface structures are derivations of the clamp tegument or, to be more precise, its outer, densely fibrous region. These results are discussed in relation to the evidence that the haptoral clamps of C. leptogaster are apparently ancient origin. PMID:25112214

  2. Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County, Oklahoma

    SciTech Connect

    J. Ford Brett; Robert V. Westermark

    2002-06-30

    This Technical Quarterly Report is for the reporting period March 31, 2002 to June 30, 2002. The report provides details of the work done on the project entitled ''Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma''. The project is divided into nine separate tasks. Several of the tasks are being worked on simultaneously, while other tasks are dependent on earlier tasks being completed. The vibration stimulation Well 111-W-27 is located in section 8 T26N R6E of the North Burbank Unit (NBU), Osage County Oklahoma. It was drilled to 3090-feet cored, logged, cased and cemented. The rig moved off August 6, 2001. Phillips Petroleum Co. has performed several core studies on the cores recovered from the test well. Standard porosity, permeability and saturation measurements have been conducted. In addition Phillips has prepared a Core Petrology Report, detailing the lithology, stratigraphy and sedimentology for Well 111-W27, NBU. Phillips has also conducted the sonic stimulation core tests, the final sonic stimulation report has not yet been released. Calumet Oil Company, the operator of the NBU, began collecting both production and injection wells information to establish a baseline for the project in the pilot field test area since May 2001. The original 7-inch Downhole Vibration Tool (DHVT) has been thoroughly tested and it has been concluded that it needs to be redesigned. An engineering firm from Fayetteville AR has been retained to assist in developing a new design for the DHVT. The project participants requested from the DOE, a no-cost extension for the project through December 31, 2002. The no-cost extension amendment to the contract was signed during this reporting period. A technical paper SPE 75254 ''Enhanced Oil Recovery with Downhole Vibration Stimulation, Osage County, Oklahoma'' was presented at the 2002 SPE/DOE Thirteenth Symposium on Improved Oil Recovery, in Tulsa OK, April 17, 2002. A one-day short course was conducted at

  3. Preliminary analysis of downhole logging data from ICDP Lake Junin drilling Project, Peru

    NASA Astrophysics Data System (ADS)

    Pierdominici, Simona; Kück, Jochem; Rodbell, Donald T.; Abbott, Mark B.

    2016-04-01

    The International Continental Drilling Programm (ICDP) has supported a scientific drilling campaign in Peru during the summer season 2015. The Lake Junin Drilling Project mainly aims at obtaining high-resolution paleoclimate records from lacustrine sediments to reconstruct the history of the continental records covering the glacial-interglacial cycles. Lake Junín is located at 4000 m a.s.l. in the tropical Andes of Peru, and is characterized by a thick (> 125 m) sediment package deposited at a high rate (0.2 to 1.0 mm yr-1). Lake Junín is one of the few lakes in the tropical Andes that predates the maximum extent of glaciation and is in a geomorphic position to record the waxing and waning of glaciers in nearby cordillera, hence making the lake a key site for the investigation of the Quaternary climate evolution in the inner-tropics of the Southern Hemisphere. Continous coring was performed at three sites in overall 11 boreholes on the lake with at least two overlapping boreholes per site to avoid core gaps. The depth of the boreholes varied between approx. 30 m and 110 m depending on the drill site. The core bit had a bit size of 122.6 mm and yielded a core diameter of 85 mm. Upon completion of coring operations downhole geophysical logging was performed in five of the 11 boreholes (1A, 1C, 1D, 2A and 3B) by the Operational Support Group of ICDP. The main objective was to record in-situ the physical properties of the lacustrine sediments of Lake Junin. Downhole logs provide a powerful tool to fill in information at intervals with core gaps and as depth reference for depth matching of the discontinous cores. Furthermore it will be used for the lithological reconstruction and interpretation. The OSG downhole logging comprised total and spectrum gamma ray, magnetic susceptibility, borehole geometry, temperature, and sonic P-wave velocity. Unstable and collapsing borehole walls made it neccessary to carry out logging in several sections instead of in one run. The

  4. Characterization of Lesser Antilles Volcanic Landslide Deposits from Downhole Logging, IODP Expedition 340

    NASA Astrophysics Data System (ADS)

    Slagle, A. L.; Morgan, S.; Expedition 340 Scientific Party, .

    2012-12-01

    The Lesser Antilles Arc is an ideal location to study the constructive and destructive processes associated with island arc volcanism. With a range of magmatic and eruptive styles occurring across the Arc, this study area provides an excellent opportunity to capture a variety of related, but different material and measurements. This project focuses on four of the nine sites drilled during Integrated Ocean Drilling Program Expedition 340 which took place in March-April 2012. Holes U1394B and U1395B were drilled through deposits offshore Montserrat in the north of the Arc while Holes U1397B and U1399C penetrated deposits offshore Martinique in the south. Here we present a summary of the downhole logging data from these four sites and provide a preliminary comparison of northern debris deposits with southern debris deposits based on the different logging datasets acquired during the expedition. Wireline logging data provide a record of physical properties which can prove complementary to core data and particularly valuable over intervals where core recovery is poor. Logging data are continuous with depth, high-resolution (vertical sampling interval from 2.5 mm to 15 cm), and are measured in situ. Data recorded during Expedition 340 include electrical resistivity, spectral gamma radiation, sonic velocity, electrical images and magnetic susceptibility. In Hole U1399C a vertical seismic profile (VSP) experiment was also conducted. Shipboard analysis of logging data revealed distinct variations and downhole trends in physical properties. More detailed postcruise analyses include: the correlation of downhole and core magnetic susceptibility for core-log integration; the use of high-resolution Formation MicroScanner images for the identification of electrofacies; the integration of physical properties and structural information from the full suite of logging data for the distinction of thickness and character of turbidites; and the generation of synthetic seismograms to

  5. Field test of two high-pressure, direct-contact downhole steam generators. Volume I. Air/diesel system

    SciTech Connect

    Marshall, B.W.

    1983-05-01

    As a part of the Project DEEP STEAM to develop technology to more efficiently utilize steam for the recovery of heavy oil from deep reservoirs, a field test of a downhole steam generator (DSG) was performed. The DSG burned No. 2 diesel fuel in air and was a direct-contact, high pressure device which mixed the steam with the combustion products and injected the resulting mixture directly into the oil reservoir. The objectives of the test program included demonstration of long-term operation of a DSG, development of operational methods, assessment of the effects of the steam/combustion gases on the reservoir and comparison of this air/diesel DSG with an adjacent oxygen/diesel direct contact generator. Downhole operation of the air/diesel DSG was started in June 1981 and was terminated in late February 1982. During this period two units were placed downhole with the first operating for about 20 days. It was removed, the support systems were slightly modified, and the second one was operated for 106 days. During this latter interval the generator operated for 70% of the time with surface air compressor problems the primary source of the down time. Thermal contact, as evidenced by a temperature increase in the production well casing gases, and an oil production increase were measured in one of the four wells in the air/diesel pattern. Reservoir scrubbing of carbon monoxide was observed, but no conclusive data on scrubbing of SO/sub x/ and NO/sub x/ were obtained. Corrosion of the DSG combustor walls and some other parts of the downhole package were noted. Metallurgical studies have been completed and recommendations made for other materials that are expected to better withstand the downhole combustion environment. 39 figures, 8 tables.

  6. Clamping the Mec1/ATR checkpoint kinase into action.

    PubMed

    Majka, Jerzy; Burgers, Peter M J

    2007-05-15

    The yeast checkpoint protein kinase Mec1, the ortholog of human ATR, is the essential upstream regulator of the cell cycle checkpoint in response to DNA damage and to stalling of DNA replication forks. The activity of Mec1/ATR is not directly regulated by the DNA substrates that signal checkpoint activation. Rather the signal appears to be transduced to Mec1 by factors that interact with the signaling DNA substrates. One of these factors, the DNA damage checkpoint clamp Rad17-Mec3-Ddc1 (human 9-1-1) is loaded onto gapped DNA resulting from the partial repair of DNA damage, and the Ddc1 subunit of this complex activates Mec1. In vertebrate cells, the TopBP1 protein (Cut5 in S. pombe and Dpb11 in S. cervisiae) that is also required for establishment of the replication fork, functions during replication fork dysfunction to activate ATR. Both mechanisms of activation generally upregulate the kinase activity towards all downstream targets. PMID:17495536

  7. Position clamping in a holographic counterpropagating optical trap.

    PubMed

    Bowman, Richard; Jesacher, Alexander; Thalhammer, Gregor; Gibson, Graham; Ritsch-Marte, Monika; Padgett, Miles

    2011-05-01

    Optical traps consisting of two counterpropagating, divergent beams of light allow relatively high forces to be exerted along the optical axis by turning off one beam, however the axial stiffness of the trap is generally low due to the lower numerical apertures typically used. Using a high speed spatial light modulator and CMOS camera, we demonstrate 3D servocontrol of a trapped particle, increasing the stiffness from 0.004 to 1.5 μN m(-1). This is achieved in the "macro-tweezers" geometry [Thalhammer, J. Opt. 13, 044024 (2011); Pitzek, Opt. Express 17, 19414 (2009)], which has a much larger field of view and working distance than single-beam tweezers due to its lower numerical aperture requirements. Using a 10×, 0.2 NA objective, active feedback produces a trap with similar effective stiffness to a conventional single-beam gradient trap, of order 1 μN m(-1) in 3D. Our control loop has a round-trip latency of 10 ms, leading to a resonance at 20 Hz. This is sufficient bandwidth to reduce the position fluctuations of a 10 μm bead due to Brownian motion by two orders of magnitude. This approach can be trivially extended to multiple particles, and we show three simultaneously position-clamped beads. PMID:21643247

  8. Dynamic Clamp Analysis of Synaptic Integration in Sympathetic Ganglia

    PubMed Central

    Horn, J. P.; Kullmann, P. H. M.

    2008-01-01

    Advances in modern neuroscience require the identification of principles that connect different levels of experimental analysis, from molecular mechanisms to explanations of cellular functions, then to circuits, and, ultimately, to systems and behavior. Here, we examine how synaptic organization of the sympathetic ganglia may enable them to function as use-dependent amplifiers of preganglionic activity and how the gain of this amplification may be modulated by metabotropic signaling mechanisms. The approach combines a general computational model of ganglionic integration together with experimental tests of the model using the dynamic clamp method. In these experiments, we recorded intracellularly from dissociated bullfrog sympathetic neurons and then mimicked physiological synapses with virtual computer-generated synapses. It thus became possible to analyze the synaptic gain by recording cellular responses to complex patterns of synaptic activity that normally arise in vivo from convergent nicotinic and muscarinic synapses. The results of these studies are significant because they illustrate how gain generated through ganglionic integration may contribute to the feedback control of important autonomic behaviors, in particular to the control of the blood pressure. We dedicate this paper to the memory of Professor Vladimir Skok, whose rich legacy in synaptic physiology helped establish the modern paradigm for connecting multiple levels of analysis in studies of the nervous system. PMID:19756262

  9. One-channel Cell-attached Patch-clamp Recording

    PubMed Central

    Maki, Bruce A.; Cummings, Kirstie A.; Paganelli, Meaghan A.; Murthy, Swetha E.; Popescu, Gabriela K.

    2014-01-01

    Ion channel proteins are universal devices for fast communication across biological membranes. The temporal signature of the ionic flux they generate depends on properties intrinsic to each channel protein as well as the mechanism by which it is generated and controlled and represents an important area of current research. Information about the operational dynamics of ion channel proteins can be obtained by observing long stretches of current produced by a single molecule. Described here is a protocol for obtaining one-channel cell-attached patch-clamp current recordings for a ligand gated ion channel, the NMDA receptor, expressed heterologously in HEK293 cells or natively in cortical neurons. Also provided are instructions on how to adapt the method to other ion channels of interest by presenting the example of the mechano-sensitive channel PIEZO1. This method can provide data regarding the channel’s conductance properties and the temporal sequence of open-closed conformations that make up the channel’s activation mechanism, thus helping to understand their functions in health and disease. PMID:24961614

  10. Stochastic modal models of slender uncertain curved beams preloaded through clamping

    NASA Astrophysics Data System (ADS)

    Avalos, Javier; Richter, Lanae A.; Wang, X. Q.; Murthy, Raghavendra; Mignolet, Marc P.

    2015-01-01

    This paper addresses the stochastic modeling of the stiffness matrix of slender uncertain curved beams that are forced fit into a clamped-clamped fixture designed for straight beams. Because of the misfit with the clamps, the final shape of the clamped-clamped beams is not straight and they are subjected to an axial preload. Both of these features are uncertain given the uncertainty on the initial, undeformed shape of the beams and affect significantly the stiffness matrix associated with small motions around the clamped-clamped configuration. A modal model using linear modes of the straight clamped-clamped beam with a randomized stiffness matrix is employed to characterize the linear dynamic behavior of the uncertain beams. This stiffness matrix is modeled using a mixed nonparametric-parametric stochastic model in which the nonparametric (maximum entropy) component is used to model the uncertainty in final shape while the preload is explicitly, parametrically included in the stiffness matrix representation. Finally, a maximum likelihood framework is proposed for the identification of the parameters associated with the uncertainty level and the mean model, or part thereof, using either natural frequencies only or natural frequencies and mode shape information of the beams around their final clamped-clamped state. To validate these concepts, three simulated, computational experiments were conducted within Nastran to produce populations of natural frequencies and mode shapes of uncertain slender curved beams after clamping. The three experiments differed from each other by the nature of the clamping condition in the in-plane direction. One experiment assumed a no-slip condition (zero in-plane displacement), another a perfect slip (no in-plane force), while the third one invoked friction. The first two experiments gave distributions of frequencies with similar features while the latter one yielded a strong deterministic dependence of the frequencies on each other, a

  11. The application limits of alloyed 13%Cr tubular steels for downhole duties

    SciTech Connect

    Cooling, P.J.; Kennani, M.B.; Martin, J.W.; Nice, P.I.

    1998-12-31

    In the past few years, a new family of materials has entered the downhole tubular market, known as the ``alloyed 13%Cr steels.`` These are a development of the conventional API 5CT grade 13%Cr steels to which alloying elements of Ni, Mo and Cu have been added, hence offering a number of advantages. In the present paper, domains of application for the 95ksi grade alloyed 13%Cr steels with respect to sour service conditions have been defined on pH vs. H{sub 2}S partial pressure plots. Corrosion properties have also been determined for two other aspects; chloride stress corrosion cracking (ClSCC) and high temperature corrosion resistance. The results have reiterated the importance of solution chemistry, pH and H{sub 2}S partial pressure in defining the corrosion properties of steels.

  12. Downhole fiber optic sensing: the oilfield service provider's perspective: from the cradle to the grave

    NASA Astrophysics Data System (ADS)

    Skinner, Neal G.; Maida, John L.

    2014-06-01

    For almost three decades, interest has continued to increase with respect to the application of fiber-optic sensing techniques for the upstream oil and gas industry. This paper reviews optical sensing technologies that have been and are being adopted downhole, as well as their drivers. A brief description of the life of a well, from the cradle to the grave, and the roles fiber-optic sensing can play in optimizing production, safety, and protection of the environment are also presented. The performance expectations (accuracy, resolution, stability, and operational lifetime) that oil companies and oil service companies have for fiber-optic sensing systems is described. Additionally, the environmental conditions (high hydrostatic pressures, high temperatures, shock, vibration, crush, and chemical exposure) that these systems must tolerate to provide reliable and economically attractive oilfield monitoring solutions are described.

  13. Near-surface attenuation using traffic-induced seismic noise at a downhole array

    NASA Astrophysics Data System (ADS)

    Dikmen, S. Umit; Pinar, Ali; Edincliler, Ayse

    2016-01-01

    A novel approach is developed for estimating the near-surface attenuation using seismic noise recordings at a downhole array. The amplitude spectrum of the traffic-induced seismic noise at the engineering bedrock level exhibits a high-frequency decay between 10 and 40 Hz. Subsequently, it yields a Kappa value of 14 ± 3 ms and a quality factor of 45 ± 10 for the profile between the highway and the sensor. Likewise, using the earthquake recordings made at the surface and the engineering bedrock levels, the Kappa values are calculated as 60 and 45 ms, respectively. The difference was attributed to near-surface attenuation where the upgoing earthquake waves and the downgoing traffic-induced seismic waves traverse similar soil profiles resulting in similar Kappa values. Hence, the near-site geology attenuation properties can be derived using the seismic noise data induced by a known source at a close distance recorded at engineering bedrock level.

  14. DOE/GRI development and testing of a downhole pump for jet-assist drilling

    SciTech Connect

    1995-07-01

    The objective of this project is to accelerate development and commercialization of a high pressure downhole pump (DHP{trademark}) to be used for ultra-high pressure, jet-assisted drilling. The purpose of jet-assisted drilling is to increase the rate of penetration (ROP) in the drilling of deeper gas and oil wells where the rocks become harder and more difficult to drill. As a means to accomplishing this objective, a second generation commercial prototype of a DHP is to be designed, fabricated, tested in the laboratory, and eventually tested in the field. The design of the DOE commercial prototype DHP is current in progress. The layout of the complete DHP is expected to be completed by mid-April. Fabrication and laboratory experimentation is expected to be completed in September. Pending successful completion of the laboratory testing phase, the DOE commercial DHP should be ready for testing in the field by the end of the calendar year.

  15. Harsh-Environment Solid-State Gamma Detector for Down-hole Gas and Oil Exploration

    SciTech Connect

    Peter Sandvik; Stanislav Soloviev; Emad Andarawis; Ho-Young Cha; Jim Rose; Kevin Durocher; Robert Lyons; Bob Pieciuk; Jim Williams; David O'Connor

    2007-08-10

    The goal of this program was to develop a revolutionary solid-state gamma-ray detector suitable for use in down-hole gas and oil exploration. This advanced detector would employ wide-bandgap semiconductor technology to extend the gamma sensor's temperature capability up to 200 C as well as extended reliability, which significantly exceeds current designs based on photomultiplier tubes. In Phase II, project tasks were focused on optimization of the final APD design, growing and characterizing the full scintillator crystals of the selected composition, arranging the APD device packaging, developing the needed optical coupling between scintillator and APD, and characterizing the combined elements as a full detector system preparing for commercialization. What follows is a summary report from the second 18-month phase of this program.

  16. Evaluation of a direct contact downhole steam generator in a field environment--final results

    SciTech Connect

    Marshall, B.W.; Moreno, J.B.; Muir, J.R.

    1983-01-01

    A test program to demonstrate the operation of down-hole steam generators (DSG) in an oil field environment was conducted in the Wilmington field at Long Beach, California. Two DSG design variations were used. One burned diesel fuel in air and was placed down hole; the other burned diesel in oxygen and was located on the surface. Gas communication was established with all wells in the production patterns. Relative rates of movement of nitrogen, CO/sub 2/ and CO were inferred and the wells were monitored for any production changes. Operating lifetimes of both prototype units were limited by the corrosion of various system components. Metallurgical analyses of degraded components of the generator and support systems have been completed.

  17. Stem drive oil recovery method utilizing a downhole steam generator and anti clay-swelling agent

    SciTech Connect

    Hopkins, D. N.; Snavely, E. S.

    1985-06-11

    Viscous oil is recovered from a subterranean, viscous oil-containing formation by a steam flooding technique wherein steam is generated in a downhole steam generator located in an injection well by spontaneous combustion of a pressurized mixture of a water-soluble fuel such as sugars and alcohols dissolved in water or a stable hydrocarbon fuel-in-water emulsion containing an anti clay-swelling agent and substantially pure oxygen. The generated mixture of steam and combustion gases pass through the formation, displacing oil and reducing the oil's viscosity and the mobilized oil is produced from the formation via a spaced-apart production well. Suitable anti clay-swelling agents include metal halide salts and diammonium phosphate.

  18. Comparison of lower-frequency (<1000 Hz) downhole seismic sources for use at environmental sites

    SciTech Connect

    Elbring, G.J.

    1995-03-01

    In conjunction with crosswell seismic surveying being done at the Hanford Site in south-central Washington, four different downhole seismic sources have been tested between the same set of boreholes. The four sources evaluated were the Bolt airgun, the OYO-Conoco orbital vibrator, and two Sandia-developed vertical vibrators, one pneumatically-driven, and the other based on a magnetostrictive actuator. The sources generate seismic energy in the lower frequency range of less than 1000 Hz and have different frequency characteristics, radiation patterns, energy levels, and operational considerations. Collection of identical data sets with all four sources allows the direct comparison of these characteristics and an evaluation of the suitability of each source for a given site and target.

  19. Downhole fluid injection systems, CO2 sequestration methods, and hydrocarbon material recovery methods

    DOEpatents

    Schaef, Herbert T.; McGrail, B. Peter

    2015-07-28

    Downhole fluid injection systems are provided that can include a first well extending into a geological formation, and a fluid injector assembly located within the well. The fluid injector assembly can be configured to inject a liquid CO2/H2O-emulsion into the surrounding geological formation. CO2 sequestration methods are provided that can include exposing a geological formation to a liquid CO2/H2O-emulsion to sequester at least a portion of the CO2 from the emulsion within the formation. Hydrocarbon material recovery methods are provided that can include exposing a liquid CO2/H2O-emulsion to a geological formation having the hydrocarbon material therein. The methods can include recovering at least a portion of the hydrocarbon material from the formation.

  20. Analysis of data from a downhole oil/water separator field trial in east Texas.

    SciTech Connect

    Veil, J. A.; Langhus, B.

    2002-08-15

    The U.S. Department of Energy's (DOE's) National Petroleum Technology Office (NPTO) is interested in promoting new technologies that can produce oil and gas at a lower cost or with enhanced environmental protection at a reasonable cost. Several years ago, DOE became aware of a new technology for produced water management known as a downhole oil/water separator (or DOWS). A DOWS system separates oil from water at the bottom of a production well and injects the water directly to a disposal zone without lifting it to the surface. DOWS technology offered three potential advantages over traditional pumping systems. First, DOWS were reported to reduce the volume of produced water brought to the surface. Second, the volume of oil produced often increased. Third, because large volumes of produced water were not being lifted to the surface past drinking water zones and subsequently reinjected downward past the same drinking water zones, there was less opportunity for contamination of those zones.

  1. Gauging the feasibility of a downhole energy harvesting system through a proof-of-concept study

    NASA Astrophysics Data System (ADS)

    Kjolsing, Eric; Todd, Michael

    2016-04-01

    Hydrocarbon well operators deploy downhole reservoir monitoring equipment in order to optimize the rate at which hydrocarbons are extracted. Alternative power sources are sought that could be deployed in these harsh environments to replace or supplement standard power sources currently in use. To this end, a three phase proof-of-concept study was performed to gauge the feasibility of such a device. In the first phase a parametric study was performed to understand how high uncertainty variables affect the natural frequency of a producing hydrocarbon well. In a follow up study, the relationship between boundary conditions and system damping was investigated. In the second phase a structural housing was designed to satisfy American Petroleum Institute load cases. Using finite element models and standard tube/casing geometries, design pressures were iterated until a permissible housing design was achieved. This preliminary design provided estimates of the radial width and volume in which energy harvesting and storage elements may be situated. In the last phase a software program was developed to estimate the energy that might be harvested from user specified harvester configurations. The program is dependent on user input production tube accelerations; this permits well operators to use well-specific vibrational data as inputs to generate well-specific energy output estimates. Results indicate that a downhole energy harvesting tool is structurally feasible under reasonable operating conditions but no conclusions can be made as to the sufficiency of generated power as no in-situ acceleration time histories are available. Future work is discussed. Approved for publication, LA-UR-16-21193.

  2. Downhole Microseismic Monitoring at a Carbon Capture, Utilization, and Storage Site, Farnsworth Unit, Ochiltree County, Texas

    NASA Astrophysics Data System (ADS)

    Ziegler, A.; Balch, R. S.; van Wijk, J.

    2015-12-01

    Farnsworth Oil Field in North Texas hosts an ongoing carbon capture, utilization, and storage project. This study is focused on passive seismic monitoring at the carbon injection site to measure, locate, and catalog any induced seismic events. A Geometrics Geode system is being utilized for continuous recording of the passive seismic downhole bore array in a monitoring well. The array consists of 3-component dual Geospace OMNI-2400 15Hz geophones with a vertical spacing of 30.5m. Downhole temperature and pressure are also monitored. Seismic data is recorded continuously and is produced at a rate of over 900GB per month, which must be archived and reviewed. A Short Term Average/Long Term Average (STA/LTA) algorithm was evaluated for its ability to search for events, including identification and quantification of any false positive events. It was determined that the algorithm was not appropriate for event detection with the background level of noise at the field site and for the recording equipment as configured. Alternatives are being investigated. The final intended outcome of the passive seismic monitoring is to mine the continuous database and develop a catalog of microseismic events/locations and to determine if there is any relationship to CO2 injection in the field. Identifying the location of any microseismic events will allow for correlation with carbon injection locations and previously characterized geological and structural features such as faults and paleoslopes. Additionally, the borehole array has recorded over 1200 active sources with three sweeps at each source location that were acquired during a nearby 3D VSP. These data were evaluated for their usability and location within an effective radius of the array and were stacked to improve signal-noise ratio and are used to calibrate a full field velocity model to enhance event location accuracy. Funding for this project is provided by the U.S. Department of Energy under Award No. DE-FC26-05NT42591.

  3. System to inject steam and produce oil from the same wellbore through downhole valve switching

    SciTech Connect

    Not Available

    1992-01-01

    Various Downhole Equipment systems have been designed for typical applications in three California Oilfields,based on well data gathered from three different Operating Companies. The first system, applicable to a 2,000 ft deep reservoir (Monarch) a highly underpressured, unconsolidated sand of 200 ft net pay, located in the Midway-Sunset field, is based on the use of a new well. The second well configuration considered was the re-entry into an existing well equipped with a 7 inches casing and penetrating into two separate sandstone reservoirs, at normal pressures in the North Antelope Hills field. Only the bottom layer is presently in production through a gravel-packed 5.5 inch linear, while the upper zone is behind the cemented casing. The third case studied was the re-entry into an existing well equipped with an 8 5/8 inch casing, presently unperforated, into a thin under-pressured sand reservoir (Weber) in the Midway-Sunset field. All three California fields contain Heavy Oils of different but relatively high viscosities. A new class of potential applications of our new technology has also been considered: the recovery of Light Oil (> 20 API) by steam injection in under-pressured Carbonate reservoirs which lay at depths beyond the economic limit for conventional steam injection technology. The possibility of including this application in a Field Test proposal to the DOE, under the Class II Oil Program, is now under review by various Operators. A drilling contractor experienced in drilling multiple horizontal wells in Carbonate reservoirs and a team of reservoir engineers experienced in the recovery of Light Oil by steam in fractured reservoirs have expressed their interest in participating in such a joint Field Project. Laboratory tests on specific prototypes of Downhole Sealing Elements are underway.

  4. Investigating the Deep Biosphere using Downhole Measurements, North Pond, IODP Expedition 336

    NASA Astrophysics Data System (ADS)

    Anderson, L. M.; Salas, E. C.; Edwards, K. J.; Bach, W.; Becker, K.; Scientists, I.

    2012-12-01

    Downhole measurements acquired using logging tools are in situ, continuous measurements taken down a borehole. They provide physical property information on formations drilled, and allow for gaps in core recovery to be filled. During IODP Expedition 336 a series of three adapted triple combination tool strings were deployed at Sites 395, U1382 and U1383 (Microbiology Combo, Adapted Microbiology Combo I and Adapted Microbiology Combo II respectively). These included sondes to measure natural gamma radiation, borehole diameter, density, resistivity, temperature and density. Additionally, on each of these tool strings the basal sonde was the Deep Exploration Biosphere Investigative tool (DEBI-t). This tool was specifically designed and built for Expedition 336 to assess the presence and distribution of microbial communities in boreholes using laser induced native fluorescence. Two other tool strings incorporating the Formation MicroScanner (FMS) were deployed in order to acquire electrical images of the borehole wall and two-axis borehole diameter information (Sites U1382 and U1383); one of the strings included the sonic sonde (Site U1383). This study correlates the more standard physical property measurements and unique spectral data collected with the DEBI-t to investigate the biology found in these hostile environments. In order to examine trends in the data more objectively, the downhole measurements were also analyzed using an Iterative Non-hierarchical Cluster Analysis (INCA) program. The program starts with k random clusters, and then moves objects between those clusters aiming to (1) minimize variability within clusters and (2) maximize variability between clusters. It is a novel tool that outputs data groups, and produces independent log 'lithofacies' which can be correlated with those observed and described in recovered cores.

  5. Behavior of a hollow core photonic crystal fiber under high radial pressure for downhole application

    SciTech Connect

    Sadeghi, J. Chenari, Z.; Ziaee, F.; Latifi, H.; Santos, J. L.

    2014-02-17

    Pressure fiber sensors play an important role in downhole high pressure measurements to withstand long term operation. The purpose of this paper is to present an application of hollow core photonic crystal fiber (HC-PCF) as a high pressure sensor head for downhole application based on dispersion variation. We used a high pressure stainless steel unit to exert pressure on the sensor. The experimental results show that different wavelengths based on sagnac loop interferometer have additive sensitivities from 5 × 10{sup −5} nm/psi at 1480 nm to 1.3 × 10{sup −3} nm/psi at 1680 nm. We developed a simulation to understand the reason for difference in sensitivity of wavelengths and also the relationship between deformation of HC-PCF and dispersion variation under pressure. For this purpose, by using the finite element method, we investigated the effect of structural variation of HC-PCF on spectral transformation of two linear polarizations under 1000 psi pressure. The simulation and experimental results show exponential decay behavior of dispersion variation from −3.4 × 10{sup −6} 1/psi to −1.3 × 10{sup −6} 1/psi and from −5 × 10{sup −6} 1/psi to −1.8 × 10{sup −6} 1/psi, respectively, which were in a good accordance with each other.

  6. Experimental Evaluation of the Static Strain on the Clamping Bolt in the Structure of a Bolt-Clamped Langevin-Type Transducer

    NASA Astrophysics Data System (ADS)

    Takahashi, Toru; Adachi, Kazunari

    2008-06-01

    Bolt-clamped Langevin-type transducers (BLTs) used in high-power ultrasonics are required to realize various characteristics depending on the technical field where they are used. Specifically for high amplitude operation, the static prestress or bearing stress imposed on the piezoelectric elements in the transducer by clamping should be large enough to compensate for their low tensile strength. The authors previously calculated prestress by the finite element method (FEM), but the numerical results have not been experimentally confirmed yet because of the difficulty of directly measuring of the prestress. In this study, the authors measured the strain on the surface of the clamping bolt using strain gauges pasted on it and compared the results with those of the numerical analysis by FEM in order to confirm the validity of the calculation. The measurement has been conducted for three BLTs of identical shape. The results of the measurement show reasonable agreement with those of the numerical analysis, and thus the authors have found that the measurement of the strain on the clamping bolt gives us a practical method for indirect evaluation of the prestress actually imposed on the piezoelectric elements that changes with the turning angle of the metal block in the clamping.

  7. The Trails of Superluminal Jet Components in 3C 111

    NASA Technical Reports Server (NTRS)

    Kadler, M.; Ros, E.; Perucho, M.; Kovalev, Y. Y.; Homan, D. C.; Agudo, I.; Kellermann, K. I.; Aller, M. F.; Aller, H. D.; Lister, M. L.; Zensus, J. A.

    2007-01-01

    The parsec-scale radio jet of the broad-line radio galaxy 3C 111 has been monitored since 1995 as part of the 2cm Survey and MOJAVE monitoring observations conducted with the VLBA. Here, we present results from 18 epochs of VLBA observations of 3C 111 and from 18 years of radio flux density monitoring observations conducted at the University of Michigan. A major radio flux-density outburst of 3C 111 occurred in 1996 and was followed by a particularly bright plasma ejection associated with a superluminal jet component. This major event allows us to study a variety of processes associated with outbursts of radio-loud AGN in much greater detail than possible in other cases: the primary perturbation gives rise to the formation of a forward and a backward-shock, which both evolve in characteristically different ways and allow us to draw conclusions about the workflow of jet-production events; the expansion, acceleration and recollimation of the ejected jet plasma in an environment with steep pressure and density gradients are revealed; trailing components are formed in the wake of the primary perturbation as a result of Kelvin- Helmholtz instabilities from the interaction of the jet with the external medium. The jet-medium interaction is further scrutinized by the linear-polarization signature of jet components traveling along the jet and passing a region of steep pressure/density gradients.

  8. Optimal High-TC Superconductivity in Cs3C60

    NASA Astrophysics Data System (ADS)

    Harshman, Dale; Fiory, Anthony

    The highest superconducting transition temperatures in the (A1-xBx)3C60 superconducting family are seen in the A15 and FCC structural phases of Cs3C60 (optimized under hydrostatic pressure), exhibiting measured values for near-stoichiometric samples of TC0 meas . = 37.8 K and 35.7 K, respectively. It is argued these two Cs-intercalated C60 compounds represent the optimal materials of their respective structures, with superconductivity originating from Coulombic e- h interactions between the C60 molecules, which host the n-type superconductivity, and mediating holes associated with the Cs cations. A variation of the interlayer Coulombic pairing model [Harshman and Fiory, J. Supercond. Nov. Magn. 28 ̲, 2967 (2015), and references therein] is introduced in which TC0 calc . ~ 1 / lζ , where l relates to the mean spacing between interacting charges on surfaces of the C60 molecules, and ζ is the average radial distance between the surface of the C60 molecules and the neighboring Cs cations. For stoichiometric Cs3C60, TC0 calc . = 38.08 K and 35.67 K for the A15 and FCC macrostructures, respectively; the dichotomy is attributable to differences in ζ.

  9. The double transverse microvascular clamp: a new instrument for microsurgical anastomoses.

    PubMed

    El-Shazly, Mohamed

    2012-11-01

    Since the introduction of microvascular surgeries, the sophisticated ideas and techniques of tissue transplantations are continually advancing and searching for the best work conditions to present the best outcomes in these critical interferences. Every tissue transplant has its donor vessels, artery and vein, which should be anastomosed to recipient vessels. A new instrument, the double transverse microvascular clamp (DTMC), has been developed to be applied simultaneously, as one clamp, to both the artery and its accompanying vein. The transverse design of this clamp keeps the artery separate from its vein, allowing each anastomosis to be performed more easily. The limited clamp surface area minimizes the glazing and blurring effects. Applying only one clamp to the two vessels presents more work space and overcomes the crowdedness caused by the use of two single clamps. Using a DTMC on both the recipient and donor vessels provides optimal suture maneuverability and ideal work situation compared with the use of two double approximating clamps. We believe this DTMC would be a valuable addition to the microsurgical instruments market. PMID:22711201

  10. The checkpoint clamp activates Mec1 kinase during initiation of the DNA damage checkpoint

    PubMed Central

    Majka, Jerzy; Niedziela-Majka, Anita; Burgers, Peter M. J.

    2007-01-01

    SUMMARY Yeast Mec1/Ddc2 protein kinase, the ortholog of human ATR/ATRIP, plays a central role in the DNA-damage checkpoint. The PCNA-like clamp Rad17/Mec3/Ddc1 (the 9-1-1 complex in human) and its loader Rad24-RFC are also essential components of this signal transduction pathway. Here we have studied the role of the clamp in regulating Mec1, and delineate how the signal generated by DNA lesions is transduced to the Rad53 effector kinase. The checkpoint clamp greatly activates the kinase activity of Mec1, but only if the clamp is appropriately loaded upon partial duplex DNA. Activated Mec1 phosphorylates the Ddc1 and Mec3 subunits of the clamp, the Rad24 subunit of the loader, and the Rpa1 and Rpa2 subunits of RPA. Phosphorylation of Rad53, and of human PHAS-1, a non-specific target, also requires a properly loaded clamp. Phosphorylation and binding studies with individual clamp subunits indicate that the Ddc1 subunit mediates the functional interactions with Mec1. PMID:17189191

  11. The checkpoint clamp activates Mec1 kinase during initiation of the DNA damage checkpoint.

    PubMed

    Majka, Jerzy; Niedziela-Majka, Anita; Burgers, Peter M J

    2006-12-28

    Yeast Mec1/Ddc2 protein kinase, the ortholog of human ATR/ATRIP, plays a central role in the DNA damage checkpoint. The PCNA-like clamp Rad17/Mec3/Ddc1 (the 9-1-1 complex in human) and its loader Rad24-RFC are also essential components of this signal transduction pathway. Here we have studied the role of the clamp in regulating Mec1, and we delineate how the signal generated by DNA lesions is transduced to the Rad53 effector kinase. The checkpoint clamp greatly activates the kinase activity of Mec1, but only if the clamp is appropriately loaded upon partial duplex DNA. Activated Mec1 phosphorylates the Ddc1 and Mec3 subunits of the clamp, the Rad24 subunit of the loader, and the Rpa1 and Rpa2 subunits of RPA. Phosphorylation of Rad53, and of human PHAS-1, a nonspecific target, also requires a properly loaded clamp. Phosphorylation and binding studies with individual clamp subunits indicate that the Ddc1 subunit mediates the functional interactions with Mec1. PMID:17189191

  12. Motion of a DNA Sliding Clamp Observed by Single Molecule Fluorescence Spectroscopy*S⃞

    PubMed Central

    Laurence, Ted A.; Kwon, Youngeun; Johnson, Aaron; Hollars, Christopher W.; O'Donnell, Mike; Camarero, Julio A.; Barsky, Daniel

    2008-01-01

    DNA sliding clamps attach to polymerases and slide along DNA to allow rapid, processive replication of DNA. These clamps contain many positively charged residues that could curtail the sliding due to attractive interactions with the negatively charged DNA. By single-molecule spectroscopy we have observed a fluorescently labeled sliding clamp (polymerase III β subunit or β clamp) loaded onto freely diffusing, single-stranded M13 circular DNA annealed with fluorescently labeled DNA oligomers of up to 90 bases. We find that the diffusion constant for the β clamp diffusing along DNA is on the order of 10–14 m2/s, at least 3 orders of magnitude less than that for diffusion through water alone. We also find evidence that the β clamp remains at the 3′ end in the presence of Escherichia coli single-stranded-binding protein. These results may imply that the clamp not only acts to hold the polymerase on the DNA but also prevents excessive drifting along the DNA. PMID:18556658

  13. Solutions for transients in arbitrarily branching cables: III. Voltage clamp problems.

    PubMed Central

    Major, G

    1993-01-01

    Branched cable voltage recording and voltage clamp analytical solutions derived in two previous papers are used to explore practical issues concerning voltage clamp. Single exponentials can be fitted reasonably well to the decay phase of clamped synaptic currents, although they contain many underlying components. The effective time constant depends on the fit interval. The smoothing effects on synaptic clamp currents of dendritic cables and series resistance are explored with a single cylinder + soma model, for inputs with different time courses. "Soma" and "cable" charging currents cannot be separated easily when the soma is much smaller than the dendrites. Subtractive soma capacitance compensation and series resistance compensation are discussed. In a hippocampal CA1 pyramidal neurone model, voltage control at most dendritic sites is extremely poor. Parameter dependencies are illustrated. The effects of series resistance compound those of dendritic cables and depend on the "effective capacitance" of the cell. Plausible combinations of parameters can cause order-of-magnitude distortions to clamp current waveform measures of simulated Schaeffer collateral inputs. These voltage clamp problems are unlikely to be solved by the use of switch clamp methods. PMID:8369450

  14. [A data interface based on USB bus technology for full auto patch-clamp system].

    PubMed

    Liu, Youlin; Hu, Yang; Qu, Anlian

    2006-04-01

    A USB bus based data interface technology for full auto Patch-Clamp system is discussed in the article. The main controller is CY2131QC (Cypress) and the logic controller is EPM3256A (Altera). Optocouplers are used to get rid of the noise from the interface. It makes the installation of the Patch-Clamp system easier by using the USB bus, and is suitable for the new generation of the Patch-Clamp system with a high speed of 1M bytes/s. PMID:16706338

  15. Voltage clamping single cells in intact malpighian tubules of mosquitoes.

    PubMed

    Masia, R; Aneshansley, D; Nagel, W; Nachman, R J; Beyenbach, K W

    2000-10-01

    Principal cells of the Malpighian tubule of the yellow fever mosquito were studied with the methods of two-electrode voltage clamp (TEVC). Intracellular voltage (V(pc)) was -86.7 mV, and input resistance (R(pc)) was 388.5 kOmega (n = 49 cells). In six cells, Ba(2+) (15 mM) had negligible effects on V(pc), but it increased R(pc) from 325.3 to 684.5 kOmega (P < 0.001). In the presence of Ba(2+), leucokinin-VIII (1 microM) increased V(pc) to -101.8 mV (P < 0.001) and reduced R(pc) to 340.2 kOmega (P < 0.002). Circuit analysis yields the following: basolateral membrane resistance, 652. 0 kOmega; apical membrane resistance, 340.2 kOmega; shunt resistance (R(sh)), 344.3 kOmega; transcellular resistance, 992.2 kOmega. The fractional resistance of the apical membrane (0.35) and the ratio of transcellular resistance and R(sh) (3.53) agree closely with values obtained by cable analysis in isolated perfused tubules and confirm the usefulness of TEVC methods in single principal cells of the intact Malpighian tubule. Dinitrophenol (0.1 mM) reversibly depolarized V(pc) from -94.3 to -10.7 mV (P < 0.001) and reversibly increased R(pc) from 412 to 2,879 kOmega (P < 0.001), effects that were duplicated by cyanide (0.3 mM). Significant effects of metabolic inhibition on voltage and resistance suggest a role of ATP in electrogenesis and the maintenance of conductive transport pathways. PMID:10997925

  16. Assimilatory Sulfate Reduction in C3, C3-C4, and C4 Species of Flaveria1

    PubMed Central

    Koprivova, Anna; Melzer, Michael; von Ballmoos, Peter; Mandel, Therese; Brunold, Christian; Kopriva, Stanislav

    2001-01-01

    The activity of the enzymes catalyzing the first two steps of sulfate assimilation, ATP sulfurylase and adenosine 5′-phosphosulfate reductase (APR), are confined to bundle sheath cells in several C4 monocot species. With the aim to analyze the molecular basis of this distribution and to determine whether it was a prerequisite or a consequence of the C4 photosynthetic mechanism, we compared the intercellular distribution of the activity and the mRNA of APR in C3, C3-C4, C4-like, and C4 species of the dicot genus Flaveria. Measurements of APR activity, mRNA level, and protein accumulation in six Flaveria species revealed that APR activity, cysteine, and glutathione levels were significantly higher in C4-like and C4 species than in C3 and C3-C4 species. ATP sulfurylase and APR mRNA were present at comparable levels in both mesophyll and bundle sheath cells of C4 species Flaveria trinervia. Immunogold electron microscopy demonstrated the presence of APR protein in chloroplasts of both cell types. These findings, taken together with results from the literature, show that the localization of assimilatory sulfate reduction in the bundle sheath cells is not ubiquitous among C4 plants and therefore is neither a prerequisite nor a consequence of C4 photosynthesis. PMID:11598228

  17. Comparative Characterization of Phosphoenolpyruvate Carboxylase in C3, C4, and C3-C4 Intermediate Panicum Species 1

    PubMed Central

    Holaday, A. Scott; Black, Clanton C.

    1981-01-01

    Various properties of phosphoenolpyruvate carboxylases were compared in leaf preparations from C3-C4 intermediate, C3, and C4Panicum species. Values of Vmax in micromoles per milligram chlorophyll per hour at pH 8.3 were 57 to 75 for the enzyme from Panicum milioides, Panicum schenckii, and Panicum decipiens (all C3-C4). The values for Panicum laxum (C3) and Panicum prionitis (C4) were 20 to 40 and 952 to 1374, respectively. The Vmax values did not change at pH 7.3 except for the C4 value, which increased about 24%. At pH 8.3, the phosphoenolpyruvate carboxylases from C3 and C3-C4 species had slightly higher Km HCO3− and lower K′ phosphoenolpyruvate values than did the C4 enzyme. With each species at pH 7.3, all K′ phosphoenolpyruvate values were 2- to 4-fold greater. The enzyme from all species was inhibited 85 to 90% by 1 millimolar malate at rate-limiting phosphoenolpyruvate and Mg2+ levels. With low levels of malate, 0.2 millimolar, the rate curve with respect to phosphoenolpyruvate was distinctly sigmoidal, and the inhibition was not eliminated at 5 millimolar phosphoenolpyruvate. Malate at 10 millimolar protected all phosphoenolpyruvate carboxylases from inactivation at 55 C at pH 5.5, but not at pH 8.3. Aspartate did not protect well. When incubated at 37 C at pH 8.3 without phosphoenolpyruvate, but with HCO3−, the enzyme from several C4 grasses lost 92 to 98% of the initial activity after 4 minutes, whereas the enzymes from C3 and C3-C4Panicum species retained 60 to 70% of their activities. In contrast, 5 millimolar phosphoenolpyruvate stabilized the enzyme at 37 C in all plant extracts. The phosphoenolpyruvate carboxylase from C3-C4 intermediate Panicum species has properties most similar to the enzyme from C3Panicum species. The higher leaf activity of the enzyme from the intermediate plants than from C3 species is not due to any unusual property assayed other than a higher Vmax. PMID:16661669

  18. X-rays from the SNR 3C 391

    NASA Technical Reports Server (NTRS)

    Seward, F. D.; Wang, Z. R.

    1984-01-01

    An X-ray map and spectral information were obtained from a short Einstein observation of 3C 391 (G31.9 + 0.0). Both X-ray and radio emission appear to come from an irregular shell 5 arcmin in diameter. For a distance of 11 kpc the X-ray luminosity is at least 10 to the 35th ergs/sec. The luminosity, the radius, and the temperature are about as expected from a middle-aged SNR expanding into a medium with density a few tenths of an atom per cu cm.

  19. Discovery of an optical synchrotron jet in 3C 264

    NASA Technical Reports Server (NTRS)

    Crane, P.; Peletier, R.; Baxter, D.; Sparks, W. B.; Albrecht, R.; Barbieri, C.; Blades, J. C.; Boksenberg, A.; Deharveng, J. M.; Disney, M. J.

    1993-01-01

    Observations with the Faint Object Camera on board the Hubble Space Telescope have revealed a new optical jet in the core of the elliptical galaxy NGC 3862 (3C 264). Morphologically, this jet is similar to the synchrotron jets seen in other galaxies, as it shows knots and bifurcations. The optical spectral index is also similar to that found in other jets. Thus, the nucleus of NGC 3862 appears to contain the fifth known example of an optical synchrotron jet. Since NGC 3862 is a typical radio-loud elliptical galaxy, it seems likely that many nonthermal jets found in the radio continuum may also have optical counterparts.

  20. The optical variability periodicity analysis of 3C273

    NASA Astrophysics Data System (ADS)

    Fan, J. H.; Romero, G. E.; Lin, R. G.

    2001-02-01

    The authors have compiled measurements of ~ 110 years in the B-band of the quasar 3C273 and used this database to search for periodicity signals in the optical light curve. Two different methods were applied: the Jurkevich technique and the discrete correlation function (DCF) method. They revealed the existence of periods of 2.0, (13.65+/-0.20) and (22.50+/-0.20) years in the source variability. The possible origin of such a behavior is also discussed.

  1. Infrared variability properties of the blazar 3C 279

    NASA Astrophysics Data System (ADS)

    Fan, J. H.

    1999-10-01

    The long-term (about 27 years) near-infrared K light curve is constructed from the published literature for the blazar 3C 279. The Jurkevich method is adopted to analyse the periodicity, and a strong 7.1+/-0.44yr period is found, suggesting that the next near-infrared outburst will occur in 2002/03. The correlation between colour index (spectral index) and magnitude is discussed, and a significant correlation between (J-H) and K is found with a correlation coefficient r=0.72 (p=2.0x10^-10), which is consistent with Brown et al.'s proposal.

  2. Photopolarimetry of Blazar 3C454.3 from MIRO

    NASA Astrophysics Data System (ADS)

    Baliyan, Ks; Ganesh, S.; Chandra, Sunil; Joshi, Uc

    2009-12-01

    The Blazar 3C 454.3 has been active in Gamma-rays, optical and X- rays since Sept. 2009 ( Atel #2181, #2200, #2201). Very recently, it has been reported to be flaring up in the optical, X-ray and gamma-ray energy regimes(ATel #2322; #2325; #2326; #2328; #2329; #2330; #2332). In Atel #2333, Sasada et al report optical behaviour of this source on Dec 1.9 with brightness (V=14.06+/-0.02 and degree of polarization 6.0+/-0.1% on the same epoch.

  3. The optical variability of the quasar 3C 446

    SciTech Connect

    Barbieri, C.; Vio, R.; Cappellaro, E; Turatto, M Padova Osservatorio Astronomico, Padua )

    1990-08-01

    The optical variability of the quasar 3C 446 is investigated using power spectrum and structure function analysis along with a new set of observations that extend the available data till 1989. No contradiction is found between the PS and SF analyses. The presence of the 1540-day periodicity is strengthened by the occurrence of the 1988 luminosity peak, suggesting that the next burst will occur in the northern spring of 1992. The time series of the quasar is nonstationary. The light variations are determined by a sequence of luminosity bursts, mostly regularly spaced in time and lasting up to 2 yr. 25 refs.

  4. Substrate Clamping Effects on Irreversible Domain Wall Dynamics in Lead Zirconate Titanate Thin Films

    SciTech Connect

    Griggio, Flavio; Jesse, Stephen; Kumar, Amit; Ovchinnikov, Oleg S; Kim, H.; Jackson, T. N.; Damjanovic, Dragan; Kalinin, Sergei V; Trolier-Mckinstry, Susan E

    2012-01-01

    The role of long-range strain interactions on domain wall dynamics is explored through macroscopic and local measurements of nonlinear behavior in mechanically clamped and released polycrystalline lead zirconate-titanate (PZT) films. Released films show a dramatic change in the global dielectric nonlinearity and its frequency dependence as a function of mechanical clamping. Furthermore, we observe a transition from strong clustering of the nonlinear response for the clamped case to almost uniform nonlinearity for the released film. This behavior is ascribed to increased mobility of domain walls. These results suggest the dominant role of collective strain interactions mediated by the local and global mechanical boundary conditions on the domain wall dynamics. The work presented in this Letter demonstrates that measurements on clamped films may considerably underestimate the piezoelectric coefficients and coupling constants of released structures used in microelectromechanical systems, energy harvesting systems, and microrobots.

  5. Finite element analysis on factors influencing the clamping force in an electrostatic chuck

    NASA Astrophysics Data System (ADS)

    Xingkuo, Wang; Jia, Cheng; Kesheng, Wang; Yiyong, Yang; Yuchun, Sun; Minglu, Cao; Linhong, Ji

    2014-09-01

    As one of the core components of IC manufacturing equipment, the electrostatic chuck (ESC) has been widely applied in semiconductor processing such as etching, PVD and CVD. The clamping force of the ESC is one of the most important technical indicators. A multi-physics simulation software COMSOL is used to analyze the factors influencing the clamping force. The curves between the clamping force and the main parameters such as DC voltage, electrode thickness, electrode radius, dielectric thickness and helium gap are obtained. Moreover, the effects of these factors on the clamping force are investigated by means of orthogonal experiments. The results show that the factors can be ranked in order of voltage, electrode radius, helium gap and dielectric thickness according to their importance, which may offer certain reference for the design of ESCs.

  6. Acoustic plane waves incident on an oblique clamped panel in a rectangular duct

    NASA Technical Reports Server (NTRS)

    Unz, H.; Roskam, J.

    1980-01-01

    The theory of acoustic plane waves incident on an oblique clamped panel in a rectangular duct was developed from basic theoretical concepts. The coupling theory between the elastic vibrations of the panel (plate) and the oblique incident acoustic plane wave in infinite space was considered in detail, and was used for the oblique clamped panel in the rectangular duct. The partial differential equation which governs the vibrations of the clamped panel (plate) was modified by adding to it stiffness (spring) forces and damping forces. The Transmission Loss coefficient and the Noise Reduction coefficient for oblique incidence were defined and derived in detail. The resonance frequencies excited by the free vibrations of the oblique finite clamped panel (plate) were derived and calculated in detail for the present case.

  7. The Xenopus Oocyte Cut-open Vaseline Gap Voltage-clamp Technique With Fluorometry

    PubMed Central

    Rudokas, Michael W.; Varga, Zoltan; Schubert, Angela R.; Asaro, Alexandra B.; Silva, Jonathan R.

    2014-01-01

    The cut-open oocyte Vaseline gap (COVG) voltage clamp technique allows for analysis of electrophysiological and kinetic properties of heterologous ion channels in oocytes. Recordings from the cut-open setup are particularly useful for resolving low magnitude gating currents, rapid ionic current activation, and deactivation. The main benefits over the two-electrode voltage clamp (TEVC) technique include increased clamp speed, improved signal-to-noise ratio, and the ability to modulate the intracellular and extracellular milieu. Here, we employ the human cardiac sodium channel (hNaV1.5), expressed in Xenopus oocytes, to demonstrate the cut-open setup and protocol as well as modifications that are required to add voltage clamp fluorometry capability. The properties of fast activating ion channels, such as hNaV1.5, cannot be fully resolved near room temperature using TEVC, in which the entirety of the oocyte membrane is clamped, making voltage control difficult. However, in the cut-open technique, isolation of only a small portion of the cell membrane allows for the rapid clamping required to accurately record fast kinetics while preventing channel run-down associated with patch clamp techniques. In conjunction with the COVG technique, ion channel kinetics and electrophysiological properties can be further assayed by using voltage clamp fluorometry, where protein motion is tracked via cysteine conjugation of extracellularly applied fluorophores, insertion of genetically encoded fluorescent proteins, or the incorporation of unnatural amino acids into the region of interest1. This additional data yields kinetic information about voltage-dependent conformational rearrangements of the protein via changes in the microenvironment surrounding the fluorescent molecule. PMID:24637712

  8. The TCF C-clamp DNA binding domain expands the Wnt transcriptome via alternative target recognition

    PubMed Central

    Hoverter, Nate P.; Zeller, Michael D.; McQuade, Miriam M.; Garibaldi, Angela; Busch, Anke; Selwan, Elizabeth M.; Hertel, Klemens J.; Baldi, Pierre; Waterman, Marian L.

    2014-01-01

    LEF/TCFs direct the final step in Wnt/β-catenin signalling by recruiting β-catenin to genes for activation of transcription. Ancient, non-vertebrate TCFs contain two DNA binding domains, a High Mobility Group box for recognition of the Wnt Response Element (WRE; 5′-CTTTGWWS-3′) and the C-clamp domain for recognition of the GC-rich Helper motif (5′-RCCGCC-3′). Two vertebrate TCFs (TCF-1/TCF7 and TCF-4/TCF7L2) use the C-clamp as an alternatively spliced domain to regulate cell-cycle progression, but how the C-clamp influences TCF binding and activity genome-wide is not known. Here, we used a doxycycline inducible system with ChIP-seq to assess how the C-clamp influences human TCF1 binding genome-wide. Metabolic pulse-labeling of nascent RNA with 4′Thiouridine was used with RNA-seq to connect binding to the Wnt transcriptome. We find that the C-clamp enables targeting to a greater number of gene loci for stronger occupancy and transcription regulation. The C-clamp uses Helper sites concurrently with WREs for gene targeting, but it also targets TCF1 to sites that do not have readily identifiable canonical WREs. The coupled ChIP-seq/4′Thiouridine-seq analysis identified new Wnt target genes, including additional regulators of cell proliferation. Thus, C-clamp containing isoforms of TCFs are potent transcriptional regulators with an expanded transcriptome directed by C-clamp-Helper site interactions. PMID:25414359

  9. Corrosion response of downhole steam generator assembly and instrumentation and supply line tubings at Long Beach field test

    SciTech Connect

    Weirick, L.J.

    1983-07-01

    Three families of metals were used to make the non-combustor components for Sandia's downhole steam generator assembly and supply and instrumentation lines. These three families were: first, plain carbon steel (API Grade J 55); second, austenitic stainless steels (316 and 310); and third, a nickel-base superalloy (Inconel 600). The metals in all three of these families were found to be deficient in their corrosion response. J 55 exhibited minimal to severe general corrosion (rusting). The austenitic stainless steels pitted and cracked. Inconel 600 showed both severe pitting and some intergranular attack. For the most part, these materials were found to be unsuitable for extended life in a downhole steam generator. It is recommended that Inconel 625 be used in future systems where a moderate strength material is specified and Inconel 718 be considered where a high strength material is necessary. 11 references, 45 figures, 5 tables.

  10. Photonic Crystal Cavities in Cubic (3C) Silicon Carbide

    NASA Astrophysics Data System (ADS)

    Radulaski, Marina; Babinec, Thomas; Buckley, Sonia; Rundquist, Armand; Provine, J.; Alassaad, Kassem; Ferro, Gabriel; Vuckovic, Jelena

    2014-03-01

    Silicon carbide (SiC) combines many of the outstanding material properties of other well-known optical and quantum optical materials, including strong optical nonlinearity, high Young's modulus, and a host of optically-active crystalline defects, in a single CMOS-compatible platform. For many applications in classical and quantum information processing, the material properties of the cubic silicon carbide polytype (3C-SiC) in particular are advantageous. We therefore present the design, fabrication, and characterization of high quality factor and small mode volume planar photonic crystal cavities in cubic 3C-SiC thin films (200 nm). We demonstrate cavity resonances across the infrared telecommunications band, with wavelengths from 1.25 - 1.6 μm. Finally, we highlight our progress developing higher Q/V nanobeam cavities, as well as extending this optical cavity platform towards integration with SiC color centers. PECASE Grant ECCS-10 25811, NSF Grant ECS-9731293, Stanford Graduate Fellowship, National Science Graduate Fellowship.

  11. Modeling CICR in rat ventricular myocytes: voltage clamp studies

    PubMed Central

    2010-01-01

    Background The past thirty-five years have seen an intense search for the molecular mechanisms underlying calcium-induced calcium-release (CICR) in cardiac myocytes, with voltage clamp (VC) studies being the leading tool employed. Several VC protocols including lowering of extracellular calcium to affect Ca2+ loading of the sarcoplasmic reticulum (SR), and administration of blockers caffeine and thapsigargin have been utilized to probe the phenomena surrounding SR Ca2+ release. Here, we develop a deterministic mathematical model of a rat ventricular myocyte under VC conditions, to better understand mechanisms underlying the response of an isolated cell to calcium perturbation. Motivation for the study was to pinpoint key control variables influencing CICR and examine the role of CICR in the context of a physiological control system regulating cytosolic Ca2+ concentration ([Ca2+]myo). Methods The cell model consists of an electrical-equivalent model for the cell membrane and a fluid-compartment model describing the flux of ionic species between the extracellular and several intracellular compartments (cell cytosol, SR and the dyadic coupling unit (DCU), in which resides the mechanistic basis of CICR). The DCU is described as a controller-actuator mechanism, internally stabilized by negative feedback control of the unit's two diametrically-opposed Ca2+ channels (trigger-channel and release-channel). It releases Ca2+ flux into the cyto-plasm and is in turn enclosed within a negative feedback loop involving the SERCA pump, regulating[Ca2+]myo. Results Our model reproduces measured VC data published by several laboratories, and generates graded Ca2+ release at high Ca2+ gain in a homeostatically-controlled environment where [Ca2+]myo is precisely regulated. We elucidate the importance of the DCU elements in this process, particularly the role of the ryanodine receptor in controlling SR Ca2+ release, its activation by trigger Ca2+, and its refractory characteristics

  12. Comparative analysis of Drosophila and mammalian complexins as fusion clamps and facilitators of neurotransmitter release

    PubMed Central

    Cho, Richard W.; Song, Yun; Littleton, J. Troy

    2010-01-01

    The SNARE-binding protein complexin (Cpx) has been demonstrated to regulate synaptic vesicle fusion. Previous studies are consistent with Cpx functioning either as a synaptic vesicle fusion clamp to prevent premature exocytosis, or as a facilitator to directly stimulate release. Here we examined conserved roles of invertebrate and mammalian Cpx isoforms in the regulation of neurotransmitter release using the Drosophila neuromuscular junction as a model synapse. We find that SNARE binding by Cpx is required for its role as a fusion clamp. All four mammalian Cpx proteins (mCpx), which have been demonstrated to facilitate release, also function as fusion clamps when expressed in Drosophilacpx null mutants, though their clamping abilities varies between isoforms. Moreover, expression of mCpx I, II or III isoforms dramatically enhance evoked release compared to mCpx IV or Drosophila Cpx. Differences in the clamping and facilitating properties of complexin isoforms can be partially attributed to differences in the C-terminal membrane tethering domain. Our findings indicate that the function of complexins as fusion clamps and facilitators of fusion are conserved across evolution, and that these roles are genetically separable within an isoform and across different isoforms. PMID:20678575

  13. The sliding clamp tethers the endonuclease domain of MutL to DNA

    PubMed Central

    Pillon, Monica C.; Babu, Vignesh M. P.; Randall, Justin R.; Cai, Jiudou; Simmons, Lyle A.; Sutton, Mark D.; Guarné, Alba

    2015-01-01

    The sliding clamp enhances polymerase processivity and coordinates DNA replication with other critical DNA processing events including translesion synthesis, Okazaki fragment maturation and DNA repair. The relative binding affinity of the sliding clamp for its partners determines how these processes are orchestrated and is essential to ensure the correct processing of newly replicated DNA. However, while stable clamp interactions have been extensively studied; dynamic interactions mediated by the sliding clamp remain poorly understood. Here, we characterize the interaction between the bacterial sliding clamp (β-clamp) and one of its weak-binding partners, the DNA mismatch repair protein MutL. Disruption of this interaction causes a mild mutator phenotype in Escherichia coli, but completely abrogates mismatch repair activity in Bacillus subtilis. We stabilize the MutL-β interaction by engineering two cysteine residues at variable positions of the interface. Using disulfide bridge crosslinking, we have stabilized the E. coli and B. subtilis MutL-β complexes and have characterized their structures using small angle X-ray scattering. We find that the MutL-β interaction greatly stimulates the endonuclease activity of B. subtilis MutL and supports this activity even in the absence of the N-terminal region of the protein. PMID:26384423

  14. Mechanism of polymerase collision release from sliding clamps on the lagging strand

    PubMed Central

    Georgescu, Roxana E; Kurth, Isabel; Yao, Nina Y; Stewart, Jelena; Yurieva, Olga; O'Donnell, Mike

    2009-01-01

    Replicative polymerases are tethered to DNA by sliding clamps for processive DNA synthesis. Despite attachment to a sliding clamp, the polymerase on the lagging strand must cycle on and off DNA for each Okazaki fragment. In the ‘collision release' model, the lagging strand polymerase collides with the 5′ terminus of an earlier completed fragment, which triggers it to release from DNA and from the clamp. This report examines the mechanism of collision release by the Escherichia coli Pol III polymerase. We find that collision with a 5′ terminus does not trigger polymerase release. Instead, the loss of ssDNA on filling in a fragment triggers polymerase to release from the clamp and DNA. Two ssDNA-binding elements are involved, the τ subunit of the clamp loader complex and an OB domain within the DNA polymerase itself. The τ subunit acts as a switch to enhance polymerase binding at a primed site but not at a nick. The OB domain acts as a sensor that regulates the affinity of Pol III to the clamp in the presence of ssDNA. PMID:19696739

  15. The sliding clamp tethers the endonuclease domain of MutL to DNA.

    PubMed

    Pillon, Monica C; Babu, Vignesh M P; Randall, Justin R; Cai, Jiudou; Simmons, Lyle A; Sutton, Mark D; Guarné, Alba

    2015-12-15

    The sliding clamp enhances polymerase processivity and coordinates DNA replication with other critical DNA processing events including translesion synthesis, Okazaki fragment maturation and DNA repair. The relative binding affinity of the sliding clamp for its partners determines how these processes are orchestrated and is essential to ensure the correct processing of newly replicated DNA. However, while stable clamp interactions have been extensively studied; dynamic interactions mediated by the sliding clamp remain poorly understood. Here, we characterize the interaction between the bacterial sliding clamp (β-clamp) and one of its weak-binding partners, the DNA mismatch repair protein MutL. Disruption of this interaction causes a mild mutator phenotype in Escherichia coli, but completely abrogates mismatch repair activity in Bacillus subtilis. We stabilize the MutL-β interaction by engineering two cysteine residues at variable positions of the interface. Using disulfide bridge crosslinking, we have stabilized the E. coli and B. subtilis MutL-β complexes and have characterized their structures using small angle X-ray scattering. We find that the MutL-β interaction greatly stimulates the endonuclease activity of B. subtilis MutL and supports this activity even in the absence of the N-terminal region of the protein. PMID:26384423

  16. A novel monolithic piezoelectric actuated flexure-mechanism based wire clamp for microelectronic device packaging.

    PubMed

    Liang, Cunman; Wang, Fujun; Tian, Yanling; Zhao, Xingyu; Zhang, Hongjie; Cui, Liangyu; Zhang, Dawei; Ferreira, Placid

    2015-04-01

    A novel monolithic piezoelectric actuated wire clamp is presented in this paper to achieve fast, accurate, and robust microelectronic device packaging. The wire clamp has compact, flexure-based mechanical structure and light weight. To obtain large and robust jaw displacements and ensure parallel jaw grasping, a two-stage amplification composed of a homothetic bridge type mechanism and a parallelogram leverage mechanism was designed. Pseudo-rigid-body model and Lagrange approaches were employed to conduct the kinematic, static, and dynamic modeling of the wire clamp and optimization design was carried out. The displacement amplification ratio, maximum allowable stress, and natural frequency were calculated. Finite element analysis (FEA) was conducted to evaluate the characteristics of the wire clamp and wire electro discharge machining technique was utilized to fabricate the monolithic structure. Experimental tests were carried out to investigate the performance and the experimental results match well with the theoretical calculation and FEA. The amplification ratio of the clamp is 20.96 and the working mode frequency is 895 Hz. Step response test shows that the wire clamp has fast response and high accuracy and the motion resolution is 0.2 μm. High speed precision grasping operations of gold and copper wires were realized using the wire clamper. PMID:25933896

  17. A novel monolithic piezoelectric actuated flexure-mechanism based wire clamp for microelectronic device packaging

    NASA Astrophysics Data System (ADS)

    Liang, Cunman; Wang, Fujun; Tian, Yanling; Zhao, Xingyu; Zhang, Hongjie; Cui, Liangyu; Zhang, Dawei; Ferreira, Placid

    2015-04-01

    A novel monolithic piezoelectric actuated wire clamp is presented in this paper to achieve fast, accurate, and robust microelectronic device packaging. The wire clamp has compact, flexure-based mechanical structure and light weight. To obtain large and robust jaw displacements and ensure parallel jaw grasping, a two-stage amplification composed of a homothetic bridge type mechanism and a parallelogram leverage mechanism was designed. Pseudo-rigid-body model and Lagrange approaches were employed to conduct the kinematic, static, and dynamic modeling of the wire clamp and optimization design was carried out. The displacement amplification ratio, maximum allowable stress, and natural frequency were calculated. Finite element analysis (FEA) was conducted to evaluate the characteristics of the wire clamp and wire electro discharge machining technique was utilized to fabricate the monolithic structure. Experimental tests were carried out to investigate the performance and the experimental results match well with the theoretical calculation and FEA. The amplification ratio of the clamp is 20.96 and the working mode frequency is 895 Hz. Step response test shows that the wire clamp has fast response and high accuracy and the motion resolution is 0.2 μm. High speed precision grasping operations of gold and copper wires were realized using the wire clamper.

  18. Peptide- and proton-driven allosteric clamps catalyze anthrax toxin translocation across membranes

    PubMed Central

    Das, Debasis; Krantz, Bryan A.

    2016-01-01

    Anthrax toxin is an intracellularly acting toxin in which sufficient information is available regarding the structure of its transmembrane channel, allowing for detailed investigation of models of translocation. Anthrax toxin, comprising three proteins—protective antigen (PA), lethal factor (LF), and edema factor—translocates large proteins across membranes. Here we show that the PA translocase channel has a transport function in which its catalytic active sites operate allosterically. We find that the phenylalanine clamp (ϕ-clamp), the known conductance bottleneck in the PA translocase, gates as either a more closed state or a more dilated state. Thermodynamically, the two channel states have >300-fold different binding affinities for an LF-derived peptide. The change in clamp thermodynamics requires distant α-clamp and ϕ-clamp sites. Clamp allostery and translocation are more optimal for LF peptides with uniform stereochemistry, where the least allosteric and least efficiently translocated peptide had a mixed stereochemistry. Overall, the kinetic results are in less agreement with an extended-chain Brownian ratchet model but, instead, are more consistent with an allosteric helix-compression model that is dependent also on substrate peptide coil-to-helix/helix-to-coil cooperativity. PMID:27506790

  19. Peptide- and proton-driven allosteric clamps catalyze anthrax toxin translocation across membranes.

    PubMed

    Das, Debasis; Krantz, Bryan A

    2016-08-23

    Anthrax toxin is an intracellularly acting toxin in which sufficient information is available regarding the structure of its transmembrane channel, allowing for detailed investigation of models of translocation. Anthrax toxin, comprising three proteins-protective antigen (PA), lethal factor (LF), and edema factor-translocates large proteins across membranes. Here we show that the PA translocase channel has a transport function in which its catalytic active sites operate allosterically. We find that the phenylalanine clamp (ϕ-clamp), the known conductance bottleneck in the PA translocase, gates as either a more closed state or a more dilated state. Thermodynamically, the two channel states have >300-fold different binding affinities for an LF-derived peptide. The change in clamp thermodynamics requires distant α-clamp and ϕ-clamp sites. Clamp allostery and translocation are more optimal for LF peptides with uniform stereochemistry, where the least allosteric and least efficiently translocated peptide had a mixed stereochemistry. Overall, the kinetic results are in less agreement with an extended-chain Brownian ratchet model but, instead, are more consistent with an allosteric helix-compression model that is dependent also on substrate peptide coil-to-helix/helix-to-coil cooperativity. PMID:27506790

  20. Analysis of impactor residues in tray clamps from the Long Duration Exposure Facility. Part 2: Clamps from Bay B of the satellite

    NASA Technical Reports Server (NTRS)

    Bernhard, Ronald P.; Zolensky, Michael E.

    1994-01-01

    The Long Duration Exposure Facility (LDEF) was placed in low-Earth orbit (LEO) in 1984 and recovered 5.7 years later. The LDEF was host to several individual experiments specifically designed to characterize critical aspects of meteoroid and debris environment in LEO. However, it was realized from the beginning that the most efficient use of the satellite would be to examine the entire surface for impact features. In this regard, particular interest centered on common exposed materials that faced in all LDEF pointing directions. Among the most important of these materials was the tray clamps. Therefore, in an effort to better understand the nature of particulates in LEO and their effects on spacecraft hardware, residues found in impact features on LDEF tray clamp surfaces are being analyzed. This catalog presents all data from clamps from Bay B of the LDEF. NASA Technical Memorandum 104759 has cataloged impacts that occurred on Bay B (published March 1993). Subsequent catalogs will include clamps from succeeding bays of the satellite.

  1. Three-dimensional site response at KiK-net downhole arrays

    USGS Publications Warehouse

    Thompson, Eric M.; Tanaka, Yasuo; Baise, Laurie G.; Kayen, Robert E.

    2010-01-01

    Ground motions at two Kiban-Kyoshin Network (KiK-net) strong motion downhole array sites in Hokkaido, Japan (TKCH08 in Taiki and TKCH05 in Honbetsu) illustrate the importance of three-dimensional (3D) site effects. These sites recorded the M8.0 2003 Tokachi-Oki earthquake, with recorded accelerations above 0.4 g at both sites as well as numerous ground motions from smaller events. Weak ground motions indicate that site TKCH08 is well modeled with the assumption of plane SH waves traveling through a 1D medium (SH1D), while TKCH05 is characteristic of a poor fit to the SH1D theoretical response. We hypothesized that the misfit at TKCH05results from the heterogeneity of the subsurface. To test this hypothesis, we measured four S-wave velocity profiles in the vicinity (< 300 m) of each site with the spectral analysis of surface waves (SASW) method. This KiK-net site pair is ideal for assessing the relative importance of 3D site effects and nonlinear site effects. The linear ground motions at TKCH05 isolate the 3D site effects, as we hypothesized from the linear ground motions and confirmed with our subsequent SASW surveys. The Tokachi-Oki time history at TKCH08 isolates the effects of nonlinearity from spatial heterogeneity because the 3D effects are negligible. The Tokachi-Oki time history at TKCH05 includes both nonlinear and 3D site effects. Comparisons of the accuracy of the SH1D model predictions of these surface time histories from the downhole time histories indicates that the 3D site effects are at least as important as nonlinear effects in this case. The errors associated with the assumption of a 1D medium and 1D wave propagation will be carried into a nonlinear analysis that relies on these same assumptions. Thus, the presence of 3D effects should be ruled out prior to a 1D nonlinear analysis. The SH1D residuals show that 3D effects can be mistaken for nonlinear effects.

  2. Recent CSMIP/CALTRANS Downhole Array Data and their Application in Site Specific Analysis

    NASA Astrophysics Data System (ADS)

    Haddadi, H. R.; Graizer, V.; Shakal, T.; Hipely, P.

    2002-12-01

    The California Strong Motion Instrumentation Program (CSMIP) operates 13 downhole geotechnical arrays throughout the state of California, 8 of them instrumented with the support and cooperation of California Department of Transportation (Caltrans). More than 60 low amplitude recordings from earthquakes with 2.4downhole profile of US Geological Survey and Caltrans. At the La Cienega site the shear wave velocity increases gradually from 163 m/s at the ground surface to 653 m/s at depth of 250 m. Due to vertical propagation of waves, the one dimensional wave propagation program SHAKE91 can be used to model ground motion in the layers. The earthquake ground motion at depth of 252 m is considered as the input, and the ground motion is computed at the surface, and at depths of 18 m and 100 m using SHAKE91 program. The recorded motion at the depth of 252 m consists of the two main phases: incident wave and reflected wave from the ground surface. The incident wave is used as an input ground motion in order to prevent coupling effect. Output motions are in good agreement with the actual recordings at the ground surface, 18 m and 100 m depths. The earthquake ground motion recorded at geotechnical arrays show that the incident and reflected phases of P- waves overlap in some cases (because of higher P-wave velocity the arrival time of reflected phase cannot be visually identified) and additional analysis is necessary to distinguish the arrival

  3. Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County, Oklahoma

    SciTech Connect

    J. Ford Brett; Robert V. Westermark

    2001-12-31

    This Technical Quarterly Report is for the reporting period September 30, 2001 to December 31, 2001. The report provides details of the work done on the project entitled ''Enhanced Oil Recovery with Downhole Vibration Stimulation in Osage County Oklahoma''. The project is divided into nine separate tasks. Several of the tasks are being worked on simultaneously, while other tasks are dependent on earlier tasks being completed. The vibration stimulation well was permitted as Well 111-W-27, section 8 T26N R6E Osage County Oklahoma. It was spud July 28, 2001 with Goober Drilling Rig No. 3. The well was drilled to 3090-feet cored, logged, cased and cemented. The Rig No.3 moved off August 6, 2001. Phillips Petroleum Co. has performed standard core analysis on the cores recovered from the test well. Standard porosity, permeability and saturation measurements have been conducted. Phillips has begun the sonic stimulation core tests. Calumet Oil Company, the operator of the NBU, has been to collecting both production and injection wells information to establish a baseline for the project in the pilot field test area since May 2001. The 7-inch Downhole Vibration Tool (DHVT) has been built and has been run in a shallow well for initial power source testing. This testing was done in a temporarily abandoned well, Wynona Waterflood Unit, Well No.20-12 operated by Calumet Oil Co both in October and December 2001. The data acquisition system, and rod rotating equipment performed as designed. However, the DHVT experienced two internal failures during vibration operations. The DHVT has been repaired with modifications to improve its functionality. A proposed technical paper abstract has been accepted by the SPE to be presented at the 2002 SPE/DOE Thirteenth Symposium on Improved Oil Recovery, in Tulsa OK, 13-17 April 2002. A one-day SPE sponsored short course which is planned to cover seismic stimulation efforts around the world, will be offered at the SPE/DOE Thirteenth Symposium on

  4. Imaging Fracking Zones by Microseismic Reverse Time Migration for Downhole Microseismic Monitoring

    NASA Astrophysics Data System (ADS)

    Lin, Y.; Zhang, H.

    2015-12-01

    Hydraulic fracturing is an engineering tool to create fractures in order to better recover oil and gas from low permeability reservoirs. Because microseismic events are generally associated with fracturing development, microseismic monitoring has been used to evaluate the fracking process. Microseismic monitoring generally relies on locating microseismic events to understand the spatial distribution of fractures. For the multi-stage fracturing treatment, fractures created in former stages are strong scatterers in the medium and can induce strong scattering waves on the waveforms for microseismic events induced during later stages. In this study, we propose to take advantage of microseismic scattering waves to image fracking zones by using seismic reverse time migration method. For downhole microseismic monitoring that involves installing a string of seismic sensors in a borehole near the injection well, the observation geometry is actually similar to the VSP (vertical seismic profile) system. For this reason, we adapt the VSP migration method for the common shot gather to the common event gather. Microseismic reverse-time migration method involves solving wave equation both forward and backward in time for each microseismic event. At current stage, the microseismic RTM is based on 2D acoustic wave equation (Zhang and Sun, 2008), solved by the finite-difference method with PML absorbing boundary condition applied to suppress the reflections of artificial boundaries. Additionally, we use local wavefield decomposition instead of cross-correlation imaging condition to suppress the imaging noise. For testing the method, we create a synthetic dataset for a downhole microseismic monitoring system with multiple fracking stages. It shows that microseismic migration using individual event is able to clearly reveal the fracture zone. The shorter distance between fractures and the microseismic event the clearer the migration image is. By summing migration images for many

  5. Substitutional Ge in 3C-SiC

    NASA Astrophysics Data System (ADS)

    Guedj, C.; Kolodzey, J.

    1999-02-01

    The incorporation of substitutional Ge into 3C-SiC alloys is studied theoretically with an anharmonic Keating model specifically adapted to the computation of the structural properties and the lattice dynamics of Si1-x-yGexCy alloys. Basic energy calculations show that the substitution of Si by Ge is more probable than the substitution of C by Ge in the zinc-blende silicon carbide crystal. If Ge replaces only Si, then the lattice parameter equals (0.43593±0.00002)+(0.000337±0.000002)y, where y stands for the Ge content. Hence, Vegard's law is not applicable. The alloy is characterized by a distinct phonon spectrum whose maximum peak position in cm-1 is best described by the exponential decay (243±1)+(27±2)exp[-y/(7.5±1.2)] up to the zinc-blende GeC compound.

  6. Behavior of inversion layers in 3C silicon carbide

    NASA Technical Reports Server (NTRS)

    Avila, R. E.; Kopanski, J. J.; Fung, C. D.

    1986-01-01

    A study on the field-induced surface-charge region in 3C silicon carbide (SiC) using 1 MHz capacitance-voltage (C-V) measurements at room temperature is here reported. A double column mercury probe was used on oxidized SiC substrates to form metal-oxide-semiconductor (MOS) structures. These structures were characterized in terms of the substrate doping profile, effective fixed oxide charge, and interface trap density. A distinctive feature of the MOS C-V curves from accumulation to inversion is that after going into deep depletion the capacitance rises to its equilibrium inversion level during the voltage sweep. Capacitance transient measurements indicate that the minority-carrier generation occurs at the SiO2/SiC interface.

  7. Behavior of inversion layers in 3C silicon carbide

    NASA Astrophysics Data System (ADS)

    Avila, R. E.; Kopanski, J. J.; Fung, C. D.

    1986-08-01

    A study on the field-induced surface-charge region in 3C silicon carbide (SiC) using 1 MHz capacitance-voltage (C-V) measurements at room temperature is here reported. A double column mercury probe was used on oxidized SiC substrates to form metal-oxide-semiconductor (MOS) structures. These structures were characterized in terms of the substrate doping profile, effective fixed oxide charge, and interface trap density. A distinctive feature of the MOS C-V curves from accumulation to inversion is that after going into deep depletion the capacitance rises to its equilibrium inversion level during the voltage sweep. Capacitance transient measurements indicate that the minority-carrier generation occurs at the SiO2/SiC interface.

  8. Structural Variability of 3C 111 on Parsec Scales

    NASA Technical Reports Server (NTRS)

    Grossberger, C.; Kadler, M.; Wilms, J.; Muller, C.; Beuchert, T.; Ros, E.; Ojha, R.; Aller, M.; Aller, H.; Angelakis, E.; Fuhrmann, L.; Nestoras, I.; Schmidt, R.; Zensus, J. A.; Krichbaum, T. P.; Ungerechts, H.; Sievers, A.; Riquelme, D.

    2011-01-01

    We discuss the parsec-scale structural variability of the extragalactic jet 3C 111 related to a major radio flux density outburst in 2007, The data analyzed were taken within the scope of the MOJAVE, UMRAO, and F-GAMMA programs, which monitor a large sample of the radio brightest compact extragalactic jets with the VLBA, the University of Michigan 26 m, the Effelsberg 100 m, and the IRAM 30 m radio telescopes. The analysis of the VLBA data is performed by fitting Gaussian model components in the visibility domain, We associate the ejection of bright features in the radio jet with a major flux-density outburst in 2007, The evolution of these features suggests the formation of a leading component and multiple trailing components

  9. Trisodium citrate, Na3(C6H5O7)

    PubMed Central

    Rammohan, Alagappa; Kaduk, James A.

    2016-01-01

    The crystal structure of anhydrous tris­odium citrate, Na3(C6H5O7), has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory (DFT). There are two independent five-coordinate Na+ and one six-coordinate Na+ cations in the asymmetric unit. The [NaO5] and [NaO6] polyhedra share edges and corners to form a three-dimensional framework. There are channels parallel to the a and b axes in which the remainder of the citrate anions reside. The only hydrogen bonds are an intra­molecular one between the hy­droxy group and one of the terminal carboxyl­ate O atoms and an intermolecular one between a methylene group and the hydroxyl O atom. PMID:27308044

  10. Milliarcsecond polarization structure of the superluminal quasar 3C 273

    NASA Astrophysics Data System (ADS)

    Roberts, David H.; Kollgaard, Ronald I.; Brown, Leslie F.; Gabuzda, Denise C.; Wardle, John F. C.

    1990-09-01

    A 2 x 10 marcsec-resolution determination is presented for the total intensity and linear polarization structures of the superluminal quasar 3C 273 at 5 GHz. Substantial polarized flux was detected from several superluminal components of the jet, whose fractional polarization increased symmetrically with distance from the core; the most distant component is highly polarized and exhibits a highly ordered magnetic field. Within a few marcsec of the core, the inferred magnetic field orientation varies rapidly with position along the jet. The primarily longitudinal magnetic field orientation is concluded to become established within 20 marcsec of the core. A highly disorganized magnetic field is the most plausible explanation for the low degree of polarization in the innermost regions of the jet.

  11. The Parsec-Scale Jet of Quasar 3C345

    NASA Astrophysics Data System (ADS)

    Zensus, J. A.; Rabaca, C. R.

    1993-12-01

    We discuss the parsec-scale structure of the superluminal quasar 3C345. Monitoring of the structure with VLBI at cm and mm wavelengths has shown apparent superluminal motion of at least four distinct emission features, over a distance of more than 40 pc from the stationary core (Zensus, Cohen, and Unwin, submitted to APJ). Near the core, the projected trajectories are curved and different for individual components, indicative of more complicated flow patterns than previously suspected, and consistent with motion along helical paths. The motion accelerates with increasing separation from the core, as the jet curves towards the extended kiloparsec structure. The flux evolution of individual components can be described using a generalized shock model. We apply this to component C4 and discuss the impact of orientation effects and implications for specific shock models.

  12. Extended Ly-alpha emission associated with 3C 294

    NASA Technical Reports Server (NTRS)

    Mccarthy, Patrick J.; Spinrad, Hyron; Dickinson, Mark; Van Breugel, Wil; Liebert, James; Djorgovski, S.; Eisenhardt, Peter

    1990-01-01

    Optical, IR, and radio observations of the powerful radio source 3C 294, which is surrounded by a large cloud of ionized gas, are presented. The galaxy is faint in the rest-frame UV, yet has a near-IR luminosity that is typical of radio galaxies at redshifts of order two. In contrast to the large extent of the ionized gas, the K-band image is quite compact. The emission-line cloud is closely aligned with the radio source axis and has an ionization state indicative of ionization by a nonstellar source. The velocity field of the gas has both large ordered motions and large turbulent components. The total mass required to keep the gas bound to the system is comparable to present-day massive galaxies and their halos. The velocity fields of the high-ionization lines are systematically different from Ly-alpha in a manner that is not easily understood.

  13. NIR Flaring of the Quasar 3C454.3

    NASA Astrophysics Data System (ADS)

    Carrasco, L.; Carramiñana, A.; Recillas, E.; Escobedo, G.; Porras, A.; Mayya, Y. D.; Valdes, J. R.

    2010-10-01

    We report the ongoing NIR flare of the quasar 3C454.3, also known as [HB89]2251+158. It is likely associated with a gamma ray source CGRaBSJ2253+1608 and the radio source WMAP055. It is an intermediate redshift FRSQSO Z=0.859 (RA=22:53:57.75, Dec=+16:08:53.6(J2000). On October 31th,2010 (JD 2455500.781451), we determined the NIR flux from this object to correspond to H = 11.190 +/- 0.03, 0.63mag brighter than it was two days earlier(JD 2455498.821166) when we determined it to have H = 11.820 +/- 0.03.

  14. Development of potent inhibitors of the coxsackievirus 3C protease

    SciTech Connect

    Lee, Eui Seung; Lee, Won Gil; Yun, Soo-Hyeon; Rho, Seong Hwan; Im, Isak; Yang, Sung Tae; Sellamuthu, Saravanan; Lee, Yong Jae; Kwon, Sun Jae; Park, Ohkmae K.; Jeon, Eun-Seok; Park, Woo Jin . E-mail: wjpark@gist.ac.kr; Kim, Yong-Chul . E-mail: yongchul@gist.ac.kr

    2007-06-22

    Coxsackievirus B3 (CVB3) 3C protease (3CP) plays essential roles in the viral replication cycle, and therefore, provides an attractive therapeutic target for treatment of human diseases caused by CVB3 infection. CVB3 3CP and human rhinovirus (HRV) 3CP have a high degree of amino acid sequence similarity. Comparative modeling of these two 3CPs revealed one prominent distinction; an Asn residue delineating the S2' pocket in HRV 3CP is replaced by a Tyr residue in CVB3 3CP. AG7088, a potent inhibitor of HRV 3CP, was modified by substitution of the ethyl group at the P2' position with various hydrophobic aromatic rings that are predicted to interact preferentially with the Tyr residue in the S2' pocket of CVB3 3CP. The resulting derivatives showed dramatically increased inhibitory activities against CVB3 3CP. In addition, one of the derivatives effectively inhibited the CVB3 proliferation in vitro.

  15. Intermittent selective clamping improves rat liver regeneration by attenuating oxidative and endoplasmic reticulum stress

    PubMed Central

    Ben Mosbah, I; Duval, H; Mbatchi, S-F; Ribault, C; Grandadam, S; Pajaud, J; Morel, F; Boudjema, K; Compagnon, P; Corlu, A

    2014-01-01

    Intermittent clamping of the portal trial is an effective method to avoid excessive blood loss during hepatic resection, but this procedure may cause ischemic damage to liver. Intermittent selective clamping of the lobes to be resected may represent a good alternative as it exposes the remnant liver only to the reperfusion stress. We compared the effect of intermittent total or selective clamping on hepatocellular injury and liver regeneration. Entire hepatic lobes or only lobes to be resected were subjected twice to 10 min of ischemia followed by 5 min of reperfusion before hepatectomy. We provided evidence that the effect of intermittent clamping can be damaging or beneficial depending to its mode of application. Although transaminase levels were similar in all groups, intermittent total clamping impaired liver regeneration and increased apoptosis. In contrast, intermittent selective clamping improved liver protein secretion and hepatocyte proliferation when compared with standard hepatectomy. This beneficial effect was linked to better adenosine-5′-triphosphate (ATP) recovery, nitric oxide production, antioxidant activities and endoplasmic reticulum adaptation leading to limit mitochondrial damage and apoptosis. Interestingly, transient and early chaperone inductions resulted in a controlled activation of the unfolded protein response concomitantly to endothelial nitric oxide synthase, extracellular signal-regulated kinase-1/2 (ERK1/2) and p38 MAPK activation that favors liver regeneration. Endoplasmic reticulum stress is a central target through which intermittent selective clamping exerts its cytoprotective effect and improves liver regeneration. This procedure could be applied as a powerful protective modality in the field of living donor liver transplantation and liver surgery. PMID:24603335

  16. Can selective arterial clamping with fluorescence imaging preserve kidney function during robotic partial nephrectomy?

    PubMed Central

    McClintock, Tyler R.; Bjurlin, Marc A.; Wysock, James S.; Borofsky, Michael S.; Marien, Tracy P.; Okoro, Chinonyerem; Stifelman, Michael D.

    2015-01-01

    Objectives To compare renal functional outcomes in robotic partial nephrectomy (RPN) with selective arterial clamping guided by near infrared fluorescence (NIRF) imaging to a matched cohort of patients who underwent RPN without selective arterial clamping and NIRF imaging. Methods From April 2011 to December 2012, NIRF imaging-enhanced RPN with selective clamping was utilized in 42 cases. Functional outcomes of successful cases were compared with a cohort of patients, matched by tumor size, preoperative eGFR, functional kidney status, age, sex, body mass index, and American Society of Anesthesiologists score, who underwent RPN without selective clamping and NIRF imaging. Results In matched-pair analysis, selective clamping with NIRF was associated with superior kidney function at discharge, as demonstrated by postoperative eGFR (78.2 vs 68.5 ml/min per 1.73m2; P=0.04), absolute reduction of eGFR (−2.5 vs −14.0 ml/min per 1.73m2; P<0.01) and percent change in eGFR (−1.9% vs −16.8%, P<0.01). Similar trends were noted at three month follow up but these differences became non-significant (P[eGFR]=0.07], P[absolute reduction of eGFR]=0.10, and P[percent change in eGFR]=0.07). In the selective clamping group, a total of four perioperative complications occurred in three patients, all of which were Clavien I-III. Conclusion Utilization of NIRF imaging was associated with improved short-term renal functional outcomes when compared to RPN without selective arterial clamping and NIRF imaging. With this effect attenuated at later follow-up, randomized prospective studies and long-term assessment of kidney-specific functional outcomes are needed to further assess the benefits of this technology. PMID:24909960

  17. Yielding of the clamped-wire system in the Ilizarov external fixator.

    PubMed

    Watson, M A; Matthias, K J; Maffulli, N; Hukins, D W L

    2003-01-01

    This study demonstrates that the clamped-wire system used to suspend bones within an Ilizarov external fixator yields when the perpendicular load exceeds 50 N per wire. Cyclic loading was applied to tensioned wires clamped within an Ilizarov ring component, with steadily increasing load amplitude. Wires were tested at four initial tension settings. The amount of energy lost within the clamped-wire system per load cycle was calculated for every test. The results showed that there was a consistent trend to increasing non-recoverable energy loss per load cycle when peak loads exceed 50 N for all initial tension settings. A finite element (FE) model replicating the experimental conditions was performed to investigate the levels of stress within the loaded wires. The FE model analyses showed that high stresses were generated in the wires close to the clamping sites, and that the stress levels could reasonably be expected to exceed the material yield stress when loaded to about 55 N, for all initial tension settings. The results show that material yield, accompanied by some wire slippage through the clamps, is responsible for system yield, in agreement with previous studies. Although the initial wire tension has an appreciable effect on the wire stiffness, it did not affect the elastic load range of the clamped-wire system. To prevent yield of the clamped-wire system in practice, the fixator should be assembled with sufficient wires to ensure that the load transmitted to each wire by the patient does not exceed 50 N. PMID:14558649

  18. Intermittent selective clamping improves rat liver regeneration by attenuating oxidative and endoplasmic reticulum stress.

    PubMed

    Ben Mosbah, I; Duval, H; Mbatchi, S-F; Ribault, C; Grandadam, S; Pajaud, J; Morel, F; Boudjema, K; Compagnon, P; Corlu, A

    2014-01-01

    Intermittent clamping of the portal trial is an effective method to avoid excessive blood loss during hepatic resection, but this procedure may cause ischemic damage to liver. Intermittent selective clamping of the lobes to be resected may represent a good alternative as it exposes the remnant liver only to the reperfusion stress. We compared the effect of intermittent total or selective clamping on hepatocellular injury and liver regeneration. Entire hepatic lobes or only lobes to be resected were subjected twice to 10 min of ischemia followed by 5 min of reperfusion before hepatectomy. We provided evidence that the effect of intermittent clamping can be damaging or beneficial depending to its mode of application. Although transaminase levels were similar in all groups, intermittent total clamping impaired liver regeneration and increased apoptosis. In contrast, intermittent selective clamping improved liver protein secretion and hepatocyte proliferation when compared with standard hepatectomy. This beneficial effect was linked to better adenosine-5'-triphosphate (ATP) recovery, nitric oxide production, antioxidant activities and endoplasmic reticulum adaptation leading to limit mitochondrial damage and apoptosis. Interestingly, transient and early chaperone inductions resulted in a controlled activation of the unfolded protein response concomitantly to endothelial nitric oxide synthase, extracellular signal-regulated kinase-1/2 (ERK1/2) and p38 MAPK activation that favors liver regeneration. Endoplasmic reticulum stress is a central target through which intermittent selective clamping exerts its cytoprotective effect and improves liver regeneration. This procedure could be applied as a powerful protective modality in the field of living donor liver transplantation and liver surgery. PMID:24603335

  19. 50 CFR Table 3c to Part 680 - Crab Product Codes for Economic Data Reports

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Crab Product Codes for Economic Data Reports 3c Table 3c to Part 680 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 3c Table 3c to Part 680—Crab Product Codes for...

  20. 50 CFR Table 3c to Part 680 - Crab Product Codes for Economic Data Reports

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Crab Product Codes for Economic Data Reports 3c Table 3c to Part 680 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 3c Table 3c to Part 680—Crab Product Codes for...

  1. 50 CFR Table 3c to Part 680 - Crab Product Codes for Economic Data Reports

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Crab Product Codes for Economic Data Reports 3c Table 3c to Part 680 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 3c Table 3c to Part 680—Crab Product Codes for...

  2. Subsurface sediment contamination during borehole drilling with an air-actuated down-hole hammer.

    PubMed

    Malard, Florian; Datry, Thibault; Gibert, Janine

    2005-10-01

    Drilling methods can severely alter physical, chemical, and biological properties of aquifers, thereby influencing the reliability of water samples collected from groundwater monitoring wells. Because of their fast drilling rate, air-actuated hammers are increasingly used for the installation of groundwater monitoring wells in unconsolidated sediments. However, oil entrained in the air stream to lubricate the hammer-actuating device can contaminate subsurface sediments. Concentrations of total hydrocarbons, heavy metals (Cu, Ni, Cr, Zn, Pb, and Cd), and nutrients (particulate organic carbon, nitrogen, and phosphorus) were measured in continuous sediment cores recovered during the completion of a 26-m deep borehole drilled with a down-hole hammer in glaciofluvial deposits. Total hydrocarbons, Cu, Ni, Cr and particulate organic carbon (POC) were all measured at concentrations far exceeding background levels in most sediment cores. Hydrocarbon concentration averaged 124 +/- 118 mg kg(-1) dry sediment (n = 78 samples) with peaks at depths of 8, 14, and 20 m below the soil surface (maximum concentration: 606 mg kg(-1)). The concentrations of hydrocarbons, Cu, Ni, Cr, and POC were positively correlated and exhibited a highly irregular vertical pattern, that probably reflected variations in air loss within glaciofluvial deposits during drilling. Because the penetration of contaminated air into the formation is unpreventable, the representativeness of groundwater samples collected may be questioned. It is concluded that air percussion drilling has strong limitations for well installation in groundwater quality monitoring surveys. PMID:16091299

  3. Methods and computer executable instructions for marking a downhole elongate line and detecting same

    DOEpatents

    Watkins, Arthur D.

    2003-05-13

    Methods and computer executable instructions are provided for making an elongate line (22) with a plurality of marks (30) and detecting those marks (30) to determine a distance of the elongate line (22) in a downhole or a physical integrity thereof. In a preferred embodiment, each mark comprises a plurality of particles (44) having a substantially permanent magnetizing capability adhered to an exterior surface of the elongate line (22) at preselected intervals with an epoxy paint. The particles (44) are arranged at each interval as a plurality of bands (40). Thereafter, the particles are oriented into a magnetic signature for that interval by magnetizing the particles to create a magnetic field substantially normal to the exterior surface. This facilitates detection by a Hall effect probe. The magnetic signatures are stored in a computing configuration and, once a mark is detected, a correlation is made to a unique position on the elongate line by comparison with the stored magnetic signatures. Preferred particles include samarium-cobalt and neodymium-iron-boride.

  4. Tracer dye transport from a well fitted with a downhole heat exchanger, Klamath Falls, Oregon

    SciTech Connect

    Dunstall, M.G.

    1990-02-01

    Low or medium temperature geothermal resources are often used for space and domestic hot water heating. If the resource is located at reasonably shallow depths and adjacent to a major population centre large amounts of relatively cheap, clean heat can be provided. Geothermal fluid is often brought to the surface, either under natural artesian pressure or by pumping, to be used in surface heat exchangers (SHEs). This method generally requires a second well for disposal of the cooled fluid and a substantial capital outlay for pumps and heat exchangers. Large amounts of heat can be extracted from just one or two wells using surface heat exchangers and the method can prove very cost effective in areas with a high density of energy intensive users. For smaller heat loads surface heat exchangers can become expensive and in many instances a downhole heat exchanger (DHE) installed directly in the well bore is capable of supplying cheap heat to a smaller number of users. This report first describes the methods used to carry out the series of dye tests, from well selection to injection of the dye samples. It then discusses the results of these tests in terms of how much dye was recovered, where it was recovered from and how long it took to arrive. The results of the concurrent temperature monitoring work and DHE heat output performance are also presented. Some recommendations are made for any future testing. 13 refs., 42 figs.

  5. Subsurface sediment contamination during borehole drilling with an air-actuated down-hole hammer

    NASA Astrophysics Data System (ADS)

    Malard, Florian; Datry, Thibault; Gibert, Janine

    2005-10-01

    Drilling methods can severely alter physical, chemical, and biological properties of aquifers, thereby influencing the reliability of water samples collected from groundwater monitoring wells. Because of their fast drilling rate, air-actuated hammers are increasingly used for the installation of groundwater monitoring wells in unconsolidated sediments. However, oil entrained in the air stream to lubricate the hammer-actuating device can contaminate subsurface sediments. Concentrations of total hydrocarbons, heavy metals (Cu, Ni, Cr, Zn, Pb, and Cd), and nutrients (particulate organic carbon, nitrogen, and phosphorus) were measured in continuous sediment cores recovered during the completion of a 26-m deep borehole drilled with a down-hole hammer in glaciofluvial deposits. Total hydrocarbons, Cu, Ni, Cr and particulate organic carbon (POC) were all measured at concentrations far exceeding background levels in most sediment cores. Hydrocarbon concentration averaged 124 ± 118 mg kg - 1 dry sediment ( n = 78 samples) with peaks at depths of 8, 14, and 20 m below the soil surface (maximum concentration: 606 mg kg - 1 ). The concentrations of hydrocarbons, Cu, Ni, Cr, and POC were positively correlated and exhibited a highly irregular vertical pattern, that probably reflected variations in air loss within glaciofluvial deposits during drilling. Because the penetration of contaminated air into the formation is unpreventable, the representativeness of groundwater samples collected may be questioned. It is concluded that air percussion drilling has strong limitations for well installation in groundwater quality monitoring surveys.

  6. Analysis of seismograms from a downhole array in sediments near San Francisco Bay

    USGS Publications Warehouse

    Joyner, William B.; Warrick, Richard E.; Oliver, Adolph A., III

    1976-01-01

    A four-level downhole array of three-component instruments was established on the southwest shore of San Francisco Bay to monitor the effect of the sediments on low-amplitude seismic ground motion. The deepest instrument is at a depth of 186 meters, two meters below the top of the Franciscan bedrock. Earthquake data from regional distances (29 km ≤ Δ ≤ 485 km) over a wide range of azimuths are compared with the predictions of a simple plane-layered model with material properties independently determined. Spectral ratios between the surface and bedrock computed for the one horizontal component of motion that was analyzed agree rather well with the model predictions; the model predicts the frequencies of the first three peaks within 10 percent in most cases and the height of the peaks within 50 percent in most cases. Surface time histories computed from the theoretical model predict the time variations of amplitude and frequency content reasonably well, but correlations of individual cycles cannot be made between observed and predicted traces.

  7. Direct-fired downhole steam generator: from design to field test

    SciTech Connect

    Schirmer, R.M.; Eson, R.L.

    1982-01-01

    A direct-fired downhole steam generator (DFDSG) has been developed which shows considerable promise for production of heavy oil. Generation of steam by surface boilers is inefficient because of heat losses, and air pollution curtails crude production. The technology of DFDSG is very attractive because it deals with both of these problems directly, and there are additional benefits. By carrying out the combustion process at high pressure, and then adding water, a mixture of carbon dioxide, nitrogen, and steam is charged directly into the heavy oil reservoir. This eliminates the need for expensive, and inefficient, stack scrubbers to remove sulfur dioxide, as well as sophisticated NO/sub x/ control techniques. The carbon dioxide created during the fuel burning process is absorbed by the heavy oil and increases its mobility without expending additional energy. Even the nitrogen contributes a high-velocity drag which increases both crude production rate and efficiency. DFDSG offers the potential for placing into the production zone, regardless of its depth, any quality effluent desired, from wet to superheated steam.

  8. Steam drive oil recovery method utilizing a downhole steam generator and anti clay-swelling agent

    SciTech Connect

    Hopkins, D.N.; Snavely, E.S.

    1986-03-11

    This patent describes a method of recovering viscous oil from a subterranean, permeable, viscous oil-containing formation, the formation being penetrated by at least one injection well and at least one spaced-apart production well, the wells in fluid communication with a substantial portion of the formation. The method consists of injecting a stable hydrocarbon fuel-in-water emulsion containing an anti clay-swelling agent under pressure into a downhole steam generator in the injection well; injecting substantially pure oxygen into the steam generator under pressure via the injection well which contacts the pressurized hydrocarbon fuel-in-water emulsion containing an anti clay-swelling agent in the steam generator thereby effecting spontaneous combustion of the hydrocarbon fuel to generate a mixture of steam and combustion gases that pass through the formation, displacing oil and reducing the oil's viscosity; and recovering fluids including oil from the formation via the production well. Or the method can continue injecting the pressurized mixture of hydrocarbon fuel-in-water emulsion and substantially pure oxygen for a predetermined period of time; and thereafter, discontinuing fluid injection of step (d) and opening the well to production so that fluids including oil are recovered from the formation.

  9. On using surface-source downhole-receiver logging to determine seismic slownesses

    USGS Publications Warehouse

    Boore, D.M.; Thompson, E.M.

    2007-01-01

    We present a method to solve for slowness models from surface-source downhole-receiver seismic travel-times. The method estimates the slownesses in a single inversion of the travel-times from all receiver depths and accounts for refractions at layer boundaries. The number and location of layer interfaces in the model can be selected based on lithologic changes or linear trends in the travel-time data. The interfaces based on linear trends in the data can be picked manually or by an automated algorithm. We illustrate the method with example sites for which geologic descriptions of the subsurface materials and independent slowness measurements are available. At each site we present slowness models that result from different interpretations of the data. The examples were carefully selected to address the reliability of interface-selection and the ability of the inversion to identify thin layers, large slowness contrasts, and slowness gradients. Additionally, we compare the models in terms of ground-motion amplification. These plots illustrate the sensitivity of site amplifications to the uncertainties in the slowness model. We show that one-dimensional site amplifications are insensitive to thin layers in the slowness models; although slowness is variable over short ranges of depth, this variability has little affect on ground-motion amplification at frequencies up to 5 Hz.

  10. Surface and downhole shear wave seismic methods for thick soil site investigations

    USGS Publications Warehouse

    Hunter, J.A.; Benjumea, B.; Harris, J.B.; Miller, R.D.; Pullan, S.E.; Burns, R.A.; Good, R.L.

    2002-01-01

    Shear wave velocity-depth information is required for predicting the ground motion response to earthquakes in areas where significant soil cover exists over firm bedrock. Rather than estimating this critical parameter, it can be reliably measured using a suite of surface (non-invasive) and downhole (invasive) seismic methods. Shear wave velocities from surface measurements can be obtained using SH refraction techniques. Array lengths as large as 1000 m and depth of penetration to 250 m have been achieved in some areas. High resolution shear wave reflection techniques utilizing the common midpoint method can delineate the overburden-bedrock surface as well as reflecting boundaries within the overburden. Reflection data can also be used to obtain direct estimates of fundamental site periods from shear wave reflections without the requirement of measuring average shear wave velocity and total thickness of unconsolidated overburden above the bedrock surface. Accurate measurements of vertical shear wave velocities can be obtained using a seismic cone penetrometer in soft sediments, or with a well-locked geophone array in a borehole. Examples from thick soil sites in Canada demonstrate the type of shear wave velocity information that can be obtained with these geophysical techniques, and show how these data can be used to provide a first look at predicted ground motion response for thick soil sites. ?? 2002 Published by Elsevier Science Ltd.

  11. Casingless down-hole for sealing an ablation volume and obtaining a sample for analysis

    DOEpatents

    Noble, Donald T.; Braymen, Steven D.; Anderson, Marvin S.

    1996-10-01

    A casing-less down hole sampling system for acquiring a subsurface sample for analysis using an inductively coupled plasma system is disclosed. The system includes a probe which is pushed into the formation to be analyzed using a hydraulic ram system. The probe includes a detachable tip member which has a soil point mad a barb, with the soil point aiding the penetration of the earth, and the barb causing the tip member to disengage from the probe and remain in the formation when the probe is pulled up. The probe is forced into the formation to be tested, and then pulled up slightly, to disengage the tip member and expose a column of the subsurface formation to be tested. An instrumentation tube mounted in the probe is then extended outward from the probe to longitudinally extend into the exposed column. A balloon seal mounted on the end of the instrumentation tube allows the bottom of the column to be sealed. A source of laser radiation is emitted from the instrumentation tube to ablate a sample from the exposed column. The instrumentation tube can be rotated in the probe to sweep the laser source across the surface of the exposed column. An aerosol transport system carries the ablated sample from the probe to the surface for testing in an inductively coupled plasma system. By testing at various levels in the down-hole as the probe is extracted from the soil, a profile of the subsurface formation may be obtained.

  12. Casingless down-hole for sealing an ablation volume and obtaining a sample for analysis

    DOEpatents

    Noble, D.T.; Braymen, S.D.; Anderson, M.S.

    1996-10-01

    A casing-less down hole sampling system for acquiring a subsurface sample for analysis using an inductively coupled plasma system is disclosed. The system includes a probe which is pushed into the formation to be analyzed using a hydraulic ram system. The probe includes a detachable tip member which has a soil point and a barb, with the soil point aiding the penetration of the earth, and the barb causing the tip member to disengage from the probe and remain in the formation when the probe is pulled up. The probe is forced into the formation to be tested, and then pulled up slightly, to disengage the tip member and expose a column of the subsurface formation to be tested. An instrumentation tube mounted in the probe is then extended outward from the probe to longitudinally extend into the exposed column. A balloon seal mounted on the end of the instrumentation tube allows the bottom of the column to be sealed. A source of laser radiation is emitted from the instrumentation tube to ablate a sample from the exposed column. The instrumentation tube can be rotated in the probe to sweep the laser source across the surface of the exposed column. An aerosol transport system carries the ablated sample from the probe to the surface for testing in an inductively coupled plasma system. By testing at various levels in the down-hole as the probe is extracted from the soil, a profile of the subsurface formation may be obtained. 9 figs.

  13. Downhole steam generator with improved preheating/cooling features. [Patent application

    DOEpatents

    Donaldson, A.B.; Hoke, D.E.; Mulac, A.J.

    1980-10-10

    An apparatus is described for downhole steam generation employing dual-stage preheaters for liquid fuel and for the water. A first heat exchange jacket for the fuel surrounds the fuel/oxidant mixing section of the combustor assembly downstream of the fuel nozzle and contacts the top of the combustor unit of the combustor assembly, thereby receiving heat directly from the combustion of the fuel/oxidant. A second stage heat exchange jacket surrounds an upper portion of the oxidant supply line adjacent the fuel nozzle receiving further heat from the compression heat which results from pressurization of the oxidant. The combustor unit includes an inner combustor sleeve whose inner wall defines the combustion zone. The inner combustor sleeve is surrounded by two concentric water channels, one defined by the space between the inner combustor sleeve and an intermediate sleeve, and the second defined by the space between the intermediate sleeve and an outer cylindrical housing. The channels are connected by an annular passage adjacent the top of the combustor assembly and the countercurrent nature of the water flow provides efficient cooling of the inner combustor sleeve. An annular water ejector with a plurality of nozzles is provided to direct water downwardly into the combustor unit at the boundary of the combustion zone and along the lower section of the intermediate sleeve.

  14. A hybrid fiber-optic sensing system for down-hole pressure and distributed temperature measurements

    NASA Astrophysics Data System (ADS)

    Chen, Ke; Zhou, Xinlei; Yang, Bokai; Peng, Wei; Yu, Qingxu

    2015-10-01

    A hybrid fiber-optic sensing technique, combining the extrinsic Fabry-Perot interferometer (EFPI) based pressure sensor with the incoherent optical frequency domain reflectometry (IOFDR) based distributed temperature sensor (DTS), is presented for down-hole measurements. By using a laser diode as the common light source, a highly integrated hybrid EFPI/DTS sensing system has been developed with a single fiber. With the injection current of the laser diode below lasing threshold, the broadband spontaneous emission light is used for EFPI based pressure sensing; while with the injection current above the threshold, the stimulated emission light is used for Raman based distributed temperature sensing. There is no overlap between the spectral range of the reflected light from the EFPI sensor and the spectral range of the Raman scattered light. Pressure and distributed temperature can thus be measured by using wavelength-division multiplexing (WDM) technology. Experimental results show that both the pressure and the distributed temperature are measured with little interference. Furthermore, the pressure measurement can be compensated by the measured temperature values.

  15. Trail without Catheter after Transurethral Resection of Prostate: Clamp It or Not?

    PubMed Central

    Talreja, Vikash; Saeed, Summaya; Rani, Kiran; Farid, Farah Naz; Haider, Mumtazuddin

    2016-01-01

    Background. There has been argument between clinical practitioners about clamping catheter or not prior to its removal after transurethral resection of prostate (TURP). We conducted a clinical trial to assess whether clamping has any role in early bladder tone recovery particularly in patients who undergo TURP. Methods. Randomized clinical trial was conducted at a tertiary care hospital, Karachi from January 2014 to July 2015. Eighty-six study participants who underwent TURP were randomly allocated into two groups of 43 participants each. In Group I, patient's Foley catheter was not clamped prior to its removal and in Group II Foley catheter was clamped. Data of all subjects were analyzed using SPSS version 20. Results. There was no significant difference in age and weight of resected tissues between two groups. Among 4 patients in Group I who required recatheterization, 1 patient was discharged with catheter as compared to Group II in which 2 patients were discharged with catheter (P = 0.99). Only 1 patient (2.3%) in Group II had bleeding which required recatheterization. Length of stay was significantly affected by early and free removal of Foley catheter (P < 0.001). Conclusion. The results of current study identified that clamping whether done or not had no significant impact on urinary retention. PMID:27034894

  16. Dynamics of beta and proliferating cell nuclear antigen sliding clamps in traversing DNA secondary structure.

    PubMed

    Yao, N; Hurwitz, J; O'Donnell, M

    2000-01-14

    Chromosomal replicases of cellular organisms utilize a ring shaped protein that encircles DNA as a mobile tether for high processivity in DNA synthesis. These "sliding clamps" have sufficiently large linear diameters to encircle duplex DNA and are perhaps even large enough to slide over certain DNA secondary structural elements. This report examines the Escherichia coli beta and human proliferating cell nuclear antigen clamps for their ability to slide over various DNA secondary structures. The results show that these clamps are capable of traversing a 13-nucleotide ssDNA loop, a 4-base pair stem-loop, a 4-nucleotide 5' tail, and a 15-mer bubble within the duplex. However, upon increasing the size of these structures (20-nucleotide loop, 12-base pair stem-loop, 28-nucleotide 5' tail, and 20-nucleotide bubble) the sliding motion of the beta and proliferating cell nuclear antigen over these elements is halted. Studies of the E. coli replicase, DNA polymerase III holoenzyme, in chain elongation with the beta clamp demonstrate that upon encounter with an oligonucleotide annealed in its path, it traverses the duplex and resumes synthesis on the 3' terminus of the oligonucleotide. This sliding and resumption of synthesis occurs even when the oligonucleotide contains a secondary structure element, provided the beta clamp can traverse the structure. However, upon encounter with a downstream oligonucleotide containing a large internal secondary structure, the holoenzyme clears the obstacle by strand displacing the oligonucleotide from the template. Implications of these protein dynamics to DNA transactions are discussed. PMID:10625694

  17. Nonlinear Bending Stiffness of Plates Clamped by Bolted Joints under Bending Moment

    NASA Astrophysics Data System (ADS)

    Naruse, Tomohiro; Shibutani, Yoji

    Equivalent stiffness of plates clamped by bolted joints for designing should be evaluated according to not only the strength of bolted joints but also the deformation and vibration characteristics of the structures. When the applied external axial load or the bending moment is sufficiently small, the contact surfaces of the bolted joint are stuck together, and thus both the bolt and the clamped plates deform linearly. Although the sophisticated VDI 2230 code gives the appropriate stiffness of clamped plates for the infinitesimal deformation, the stiffness may vary nonlinearly with increasing the loading because of changing the contact state. Therefore, the present paper focuses on the nonlinear behaviour of the bending stiffness of clamped plates by using Finite Element (FE) analyses, taking the contact condition on bearing surfaces and between the plates into account. The FE models of the plates with thicknesses of 3.2, 4.5, 6.0 and 9.0 mm tightened with M8, 10, 12 and 16 bolts were constructed. The relation between bending moment and bending compliance of clamped plates is found to be categorized into three regions, namely, (i) constant compliance with fully stuck contact surfaces, (ii) transition showing the nonlinear compliance, and (iii) constant compliance with one-side contact surfaces. The mechanical models for these three regions are proposed and compared with FEM solutions. The prediction on the bounds of three regions is in a fairly good agreement except the case with smaller bolts and thicker plates.

  18. A bacterial toxin inhibits DNA replication elongation through a direct interaction with the β sliding clamp.

    PubMed

    Aakre, Christopher D; Phung, Tuyen N; Huang, David; Laub, Michael T

    2013-12-12

    Toxin-antitoxin (TA) systems are ubiquitous on bacterial chromosomes, yet the mechanisms regulating their activity and the molecular targets of toxins remain incompletely defined. Here, we identify SocAB, an atypical TA system in Caulobacter crescentus. Unlike canonical TA systems, the toxin SocB is unstable and constitutively degraded by the protease ClpXP; this degradation requires the antitoxin, SocA, as a proteolytic adaptor. We find that the toxin, SocB, blocks replication elongation through an interaction with the sliding clamp, driving replication fork collapse. Mutations that suppress SocB toxicity map to either the hydrophobic cleft on the clamp that binds DNA polymerase III or a clamp-binding motif in SocB. Our findings suggest that SocB disrupts replication by outcompeting other clamp-binding proteins. Collectively, our results expand the diversity of mechanisms employed by TA systems to regulate toxin activity and inhibit bacterial growth, and they suggest that inhibiting clamp function may be a generalizable antibacterial strategy. PMID:24239291

  19. The effects of thoracic aortic cross-clamping and declamping on visceral organ blood flow.

    PubMed Central

    Oyama, M; McNamara, J J; Suehiro, G T; Suehiro, A; Sue-Ako, K

    1983-01-01

    Blood flow was measured using radioactive microspheres in 11 macaque monkeys 1) before hemorrhage shock, 2) after onset of shock, 3) after aortic cross-clamping and resuscitation, and 4) after release of the cross-clamp and stabilization. Hemodynamic parameters (cardiac output, arterial, right atrial and left atrial pressure) and blood gases were also monitored. Total abdominal organ flow fell with hemorrhage and fell further with aortic clamping. Reinfusion of shed volume did not restore abdominal organ flow (4.7% baselines) but increased LAP and cardiac output to the upper body. Release of the cross-clamp produced profound acidosis that was treated effectively with NcHCO3. After stabilization of blood, flow to kidney remained low (49% baseline) although intestinal flow was increased threefold (320% of baseline). It is clear that thoracic aortic cross-clamping in shock further compromises already reduced visceral blood flow and may contribute to the problem of ischemic multiple organ failure after resuscitation from hemorrhagic shock. PMID:6830352

  20. Organic functionalization of 3C-SiC surfaces.

    PubMed

    Schoell, Sebastian J; Sachsenhauser, Matthias; Oliveros, Alexandra; Howgate, John; Stutzmann, Martin; Brandt, Martin S; Frewin, Christopher L; Saddow, Stephen E; Sharp, Ian D

    2013-02-01

    We demonstrate the functionalization of n-type (100) and (111) 3C-SiC surfaces with organosilanes. Self-assembled monolayers (SAMs) of amino-propyldiethoxymethylsilane (APDEMS) and octadecyltrimethoxysilane (ODTMS) are formed via wet chemical processing techniques. Their structural, chemical, and electrical properties are investigated using static water contact angle measurements, atomic force microscopy, and X-ray photoelectron spectroscopy, revealing that the organic layers are smooth and densely packed. Furthermore, combined contact potential difference and surface photovoltage measurements demonstrate that the heterostructure functionality and surface potential can be tuned by utilizing different organosilane precursor molecules. Molecular dipoles are observed to significantly affect the work functions of the modified surfaces. Furthermore, the magnitude of the surface band bending is reduced following reaction of the hydroxylated surfaces with organosilanes, indicating that partial passivation of electrically active surface states is achieved. Micropatterning of organic layers is demonstrated by lithographically defined oxidation of organosilane-derived monolayers in an oxygen plasma, followed by visualization of resulting changes of the local wettability, as well as fluorescence microscopy following immobilization of fluorescently labeled BSA protein. PMID:23357505

  1. Effluent sampling of Titan 3 C vehicle exhaust

    NASA Technical Reports Server (NTRS)

    Gregory, G. L.; Storey, R. W., Jr.

    1975-01-01

    Downwind in situ ground-level measurements of the exhaust from a Titan 3 C launch vehicle were made during a normal launch. The measurement activity was conducted as part of an overall program to obtain field data for comparison with the multilayer dispersion model currently being used to predict the behavior of rocket vehicle exhaust clouds. All measurements were confined to land, ranging from the launch pad to approximately 2 kilometers downwind from the pad. Measurement systems included detectors for hydrogen chloride (HCl), carbon dioxide (CO2), and particulates (Al2O3). Airborne and ground-based optical systems were employed to monitor exhaust cloud rise, growth, and movement. These measurement systems, located along the ground track (45 deg azimuth from the launch pad) of the exhaust cloud, showed no effluents attributable to the launch. Some hydrogen chloride and aluminum oxide were detected in the surface wind direction (15 deg azimuth) from the pad. Comparisons with the model were made in three areas: (1) assumption of cloud geometry at stabilization; (2) prediction of cloud stabilization altitude; and (3) prediction of the path of cloud travel. In addition, the importance of elemental analyses of the particulate samples is illustrated.

  2. Surface-downhole and crosshole geoelectrics for monitoring of brine injection at the Ketzin CO2 storage site

    NASA Astrophysics Data System (ADS)

    Rippe, Dennis; Bergmann, Peter; Labitzke, Tim; Wagner, Florian; Schmidt-Hattenberger, Cornelia

    2016-04-01

    The Ketzin pilot site in Germany is the longest operating on-shore CO2 storage site in Europe. From June 2008 till August 2013, a total of ˜67,000 tonnes of CO2 were safely stored in a saline aquifer at depths of 630 m to 650 m. The storage site has now entered the abandonment phase, and continuation of the multi-disciplinary monitoring as part of the national project "CO2 post-injection monitoring and post-closure phase at the Ketzin pilot site" (COMPLETE) provides the unique chance to participate in the conclusion of the complete life cycle of a CO2 storage site. As part of the continuous evaluation of the functionality and integrity of the CO2 storage in Ketzin, from October 12, 2015 till January 6, 2015 a total of ˜2,900 tonnes of brine were successfully injected into the CO2 reservoir, hereby simulating in time-lapse the natural backflow of brine and the associated displacement of CO2. The main objectives of this brine injection experiment include investigation of how much of the CO2 in the pore space can be displaced by brine and if this displacement of CO2 during the brine injection differs from the displacement of formation fluid during the initial CO2 injection. Geophysical monitoring of the brine injection included continuous geoelectric measurements accompanied by monitoring of pressure and temperature conditions in the injection well and two adjacent observation wells. During the previous CO2 injection, the geoelectrical monitoring concept at the Ketzin pilot site consisted of permanent crosshole measurements and non-permanent large-scale surveys (Kiessling et al., 2010). Time-lapse geoelectrical tomographies derived from the weekly crosshole data at near-wellbore scale complemented by six surface-downhole surveys at a scale of 1.5 km showed a noticeable resistivity signature within the target storage zone, which was attributed to the CO2 plume (Schmidt-Hattenberger et al., 2011) and interpreted in terms of relative CO2 and brine saturations (Bergmann

  3. Surface-downhole and crosshole geoelectrics for monitoring of brine injection at the Ketzin CO2 storage site

    NASA Astrophysics Data System (ADS)

    Rippe, Dennis; Bergmann, Peter; Labitzke, Tim; Wagner, Florian; Schmidt-Hattenberger, Cornelia

    2016-04-01

    The Ketzin pilot site in Germany is the longest operating on-shore CO2 storage site in Europe. From June 2008 till August 2013, a total of ˜67,000 tonnes of CO2 were safely stored in a saline aquifer at depths of 630 m to 650 m. The storage site has now entered the abandonment phase, and continuation of the multi-disciplinary monitoring as part of the national project "CO2 post-injection monitoring and post-closure phase at the Ketzin pilot site" (COMPLETE) provides the unique chance to participate in the conclusion of the complete life cycle of a CO2 storage site. As part of the continuous evaluation of the functionality and integrity of the CO2 storage in Ketzin, from October 12, 2015 till January 6, 2015 a total of ˜2,900 tonnes of brine were successfully injected into the CO2 reservoir, hereby simulating in time-lapse the natural backflow of brine and the associated displacement of CO2. The main objectives of this brine injection experiment include investigation of how much of the CO2 in the pore space can be displaced by brine and if this displacement of CO2 during the brine injection differs from the displacement of formation fluid during the initial CO2 injection. Geophysical monitoring of the brine injection included continuous geoelectric measurements accompanied by monitoring of pressure and temperature conditions in the injection well and two adjacent observation wells. During the previous CO2 injection, the geoelectrical monitoring concept at the Ketzin pilot site consisted of permanent crosshole measurements and non-permanent large-scale surveys (Kiessling et al., 2010). Time-lapse geoelectrical tomographies derived from the weekly crosshole data at near-wellbore scale complemented by six surface-downhole surveys at a scale of 1.5 km showed a noticeable resistivity signature within the target storage zone, which was attributed to the CO2 plume (Schmidt-Hattenberger et al., 2011) and interpreted in terms of relative CO2 and brine saturations (Bergmann

  4. Development and Test of a 1,000 Level 3C Fiber Optic Borehole Seismic Receiver Array Applied to Carbon Sequestration

    SciTech Connect

    Paulsson, Bjorn N.P.

    2015-02-28

    To address the critical site characterization and monitoring needs for CCS programs, US Department of Energy (DOE) awarded Paulsson, Inc. in 2010 a contract to design, build and test a fiber optic based ultra-large bandwidth clamped borehole seismic vector array capable of deploying up to one thousand 3C sensor pods suitable for deployment into high temperature and high pressure boreholes. Paulsson, Inc. has completed a design or a unique borehole seismic system consisting of a novel drill pipe based deployment system that includes a hydraulic clamping mechanism for the sensor pods, a new sensor pod design and most important – a unique fiber optic seismic vector sensor with technical specifications and capabilities that far exceed the state of the art seismic sensor technologies. These novel technologies were all applied to the new borehole seismic system. In combination these technologies will allow for the deployment of up to 1,000 3C sensor pods in vertical, deviated or horizontal wells. Laboratory tests of the fiber optic seismic vector sensors developed during this project have shown that the new borehole seismic sensor technology is capable of generating outstanding high vector fidelity data with extremely large bandwidth: 0.01 – 6,000 Hz. Field tests have shown that the system can record events at magnitudes much smaller than M-2.3 at frequencies up to 2,000 Hz. The sensors have also proved to be about 100 times more sensitive than the regular coil geophones that are used in borehole seismic systems today. The fiber optic seismic sensors have furthermore been qualified to operate at temperatures over 300°C (572°F). The fibers used for the seismic sensors in the system are used to record Distributed Temperature Sensor (DTS) data allowing additional value added data to be recorded simultaneously with the seismic vector sensor data.

  5. The Role of the C-Clamp in Wnt-Related Colorectal Cancers

    PubMed Central

    Ravindranath, Aditi J.; Cadigan, Ken M.

    2016-01-01

    T-cell Factor/Lymphoid Enhancer Factor (TCF/LEF) transcription factors are major regulators of Wnt targets, and the products of the TCF7 and TCF7L2 genes have both been implicated in the progression of colorectal cancer in animal models and humans. TCFs recognize specific DNA sequences through their high mobility group (HMG) domains, but invertebrate TCFs and some isoforms of vertebrate TCF7 and TCF7L2 contain a second DNA binding domain known as the C-clamp. This review will cover the basic properties of C-clamps and their importance in Wnt signaling, using data from Drosophila, C. elegans, and mammalian cell culture. The connection between C-clamp containing TCFs and colorectal cancer will also be discussed. PMID:27527215

  6. The Anion Paradox in Sodium Taste Reception: Resolution by Voltage-Clamp Studies

    NASA Astrophysics Data System (ADS)

    Ye, Qing; Heck, Gerard L.; Desimone, John A.

    1991-11-01

    Sodium salts are potent taste stimuli, but their effectiveness is markedly dependent on the anion, with chloride yielding the greatest response. The cellular mechanisms that mediate this phenomenon are not known. This "anion paradox" has been resolved by considering the field potential that is generated by restricted electrodiffusion of the anion through paracellular shunts between taste-bud cells. Neural responses to sodium chloride, sodium acetate, and sodium gluconate were studied while the field potential was voltage-clamped. Clamping at electronegative values eliminated the anion effect, whereas clamping at electropositive potentials exaggerated it. Thus, field potentials across the lingual epithelium modulate taste reception, indicating that the functional unit of taste reception includes the taste cell and its paracellular microenvironment.

  7. The Role of the C-Clamp in Wnt-Related Colorectal Cancers.

    PubMed

    Ravindranath, Aditi J; Cadigan, Ken M

    2016-01-01

    T-cell Factor/Lymphoid Enhancer Factor (TCF/LEF) transcription factors are major regulators of Wnt targets, and the products of the TCF7 and TCF7L2 genes have both been implicated in the progression of colorectal cancer in animal models and humans. TCFs recognize specific DNA sequences through their high mobility group (HMG) domains, but invertebrate TCFs and some isoforms of vertebrate TCF7 and TCF7L2 contain a second DNA binding domain known as the C-clamp. This review will cover the basic properties of C-clamps and their importance in Wnt signaling, using data from Drosophila, C. elegans, and mammalian cell culture. The connection between C-clamp containing TCFs and colorectal cancer will also be discussed. PMID:27527215

  8. Delayed cord clamping in red blood cell alloimmunization: safe, effective, and free?

    PubMed Central

    2016-01-01

    Hemolytic disease of the newborn (HDN), an alloimmune disorder due to maternal and fetal blood type incompatibility, is associated with fetal and neonatal complications related to red blood cell (RBC) hemolysis. After delivery, without placental clearance, neonatal hyperbilirubinemia may develop from ongoing maternal antibody-mediated RBC hemolysis. In cases refractory to intensive phototherapy treatment, exchange transfusions (ET) may be performed to prevent central nervous system damage by reducing circulating bilirubin levels and to replace antibody-coated red blood cells with antigen-negative RBCs. The risks and costs of treating HDN are significant, but appear to be decreased by delayed umbilical cord clamping at birth, a strategy that promotes placental transfusion to the newborn. Compared to immediate cord clamping (ICC), safe and beneficial short-term outcomes have been demonstrated in preterm and term neonates receiving delayed cord clamping (DCC), a practice that may potentially be effective in cases RBC alloimmunization. PMID:27186530

  9. Temporary clamping of branch pulmonary artery for pulmonary hemorrhage after endarterectomy.

    PubMed

    Reddy, Srinivasa; Rajanbabu, Balram Babu; Kumar, Nalkunda Kyathaplar Sunil; Rajani, Indira

    2013-10-01

    A 49-year-old man underwent pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension. A massive pulmonary hemorrhage developed, which was identified to be from the right lower lobe, when weaning off cardiopulmonary bypass was attempted. He was managed by temporary overnight clamping of the right pulmonary artery, after the upper lobe branch. The next morning the clamp was removed, the bleeding had stopped completely, and his chest was closed. The patient was discharged on the 21st day. At 14 months' follow-up, he is in New York Heart Association functional class I. In suitable patients, temporary clamping of branch pulmonary artery can be a useful salvage measure, as in this patient. PMID:24088460

  10. Delayed cord clamping in red blood cell alloimmunization: safe, effective, and free?

    PubMed

    McAdams, Ryan M

    2016-04-01

    Hemolytic disease of the newborn (HDN), an alloimmune disorder due to maternal and fetal blood type incompatibility, is associated with fetal and neonatal complications related to red blood cell (RBC) hemolysis. After delivery, without placental clearance, neonatal hyperbilirubinemia may develop from ongoing maternal antibody-mediated RBC hemolysis. In cases refractory to intensive phototherapy treatment, exchange transfusions (ET) may be performed to prevent central nervous system damage by reducing circulating bilirubin levels and to replace antibody-coated red blood cells with antigen-negative RBCs. The risks and costs of treating HDN are significant, but appear to be decreased by delayed umbilical cord clamping at birth, a strategy that promotes placental transfusion to the newborn. Compared to immediate cord clamping (ICC), safe and beneficial short-term outcomes have been demonstrated in preterm and term neonates receiving delayed cord clamping (DCC), a practice that may potentially be effective in cases RBC alloimmunization. PMID:27186530

  11. The interplay of primer-template DNA phosphorylation status and single-stranded DNA binding proteins in directing clamp loaders to the appropriate polarity of DNA

    PubMed Central

    Hayner, Jaclyn N.; Douma, Lauren G.; Bloom, Linda B.

    2014-01-01

    Sliding clamps are loaded onto DNA by clamp loaders to serve the critical role of coordinating various enzymes on DNA. Clamp loaders must quickly and efficiently load clamps at primer/template (p/t) junctions containing a duplex region with a free 3′OH (3′DNA), but it is unclear how clamp loaders target these sites. To measure the Escherichia coli and Saccharomyces cerevisiae clamp loader specificity toward 3′DNA, fluorescent β and PCNA clamps were used to measure clamp closing triggered by DNA substrates of differing polarity, testing the role of both the 5′phosphate (5′P) and the presence of single-stranded binding proteins (SSBs). SSBs inhibit clamp loading by both clamp loaders on the incorrect polarity of DNA (5′DNA). The 5′P groups contribute selectivity to differing degrees for the two clamp loaders, suggesting variations in the mechanism by which clamp loaders target 3′DNA. Interestingly, the χ subunit of the E. coli clamp loader is not required for SSB to inhibit clamp loading on phosphorylated 5′DNA, showing that χ·SSB interactions are dispensable. These studies highlight a common role for SSBs in directing clamp loaders to 3′DNA, as well as uncover nuances in the mechanisms by which SSBs perform this vital role. PMID:25159615

  12. Measurement of transmembrane potential and current in cardiac muscle: a new voltage clamp method.

    PubMed Central

    Goldman, Y; Morad, M

    1977-01-01

    1. A single sucrose gap voltage clamp technique was developed to correct for artifacts of 'leakage' corrent and extracellular resistance making possible improved measurement of membrane current and membrane potential in cardiac muscle. 2. A fourth compartment termed 'guard gap' was added to the sucrose gap. The guard gap is maintained at the same potential as the Reinger pool, so that no extracellular leakage current can flow into the Ringer pool. Comparison of experimental results with the predictions of an idealized cable model indicates that the guard gap is effective in trapping leakage current. 3. The slow charging of membrane capacitance due to extracellular series resistance was accelerated by applying a 'pre-pulse' of the command potential past the final voltage clamp value. 4. A second technique, termed 'chopped current pulse clamp', was used to compensate for the extracellular resistance throughout the voltage clamp step. The applied current was turned on and off at a frequency of 0-5-2 kHz. The membrane potential sampled during the zero current phase was fed back through the clamp loop. 5. With either of these compensation techniques, the voltage and current traces settle to effectively constant values within 2-4 msec after initiation of a hyperpolarizing voltage clamp step from rest. 6. The membrane conductance measured by the prepulse and chopped current-pulse technique are equal and confirm a higher conductance at rest than during the plateau of the action potential. 7. The 'instantaneous' current-voltage relation of the membrane is linear during the plateau of the frog ventricular action potential. PMID:301933

  13. Observations of Titan 3C-4 Transtage Fragmentation Debris

    NASA Technical Reports Server (NTRS)

    Cowardin, Heather; Seitzer, P.; Abercromby, K.; Barker, E.; Cardona, T.; Krisko, P.; Lederer, S.

    2013-01-01

    The fragmentation of a Titan 3C-4 Transtage (1968-081) on 21 February 1992 is one of only two known break-ups in or near geosynchronous orbit. The original rocket body and 24 pieces of debris are currently being tracked by the US Space Surveillance Network (SSN). The rocket body (SSN# 3432) and several of the original fragments (SSN# 25000, 25001, 30000, and 33511) were observed in survey mode during 2004-2010 using the 0.6-m Michigan Orbital DEbris Survey Telescope (MODEST) in Chile using a broad R filter. This paper will present a size distribution for all calibrated magnitude data acquired on MODEST. Size distribution plots will also be shown using historical models for small fragmentation debris (down to 10 cm) believed to be associated with the Titan break-up. In November 2010, visible broadband photometry (Johnson/Kron-Cousins BVRI) was acquired with the 0.9-m Small and Moderate Aperture Research Telescope System (SMARTS) at the Cerro Tololo Inter-American Observatory (CTIO) in Chile on several Titan fragments (SSN# 25001, 33509, 33510) and the parent rocket body. Color index data will be used to determine the fragment brightness distribution and how the data compares to spacecraft materials measured in the laboratory using similar photometric measurement techniques. In 2012, the SSN added 16 additional fragments to the catalogue. MODEST acquired magnitude data on ten Titan fragments in late 2012 and early 2013. The magnitude distribution of all the observed fragments are analyzed as a function of time. In order to better characterize the breakup fragments spectral measurements were acquired on the original rocket body and five Titan fragments using the 6.5-m Magellan telescopes at Las Campanas Observatory in Chile. The telescopic spectra are compared with laboratory acquired spectra of materials (e.g., Aluminum and various paints) and categorized based on known absorption features for spacecraft materials.

  14. Thermal EOR: a review of insulated tubing and downhole steam generator materials evaluations

    SciTech Connect

    Aeschliman, D.P.; Moreno, J.B.; Marshall, B.W.

    1985-01-01

    A downhole steam generator post-field-test materials study program has been completed. For the particular combustor design that was tested, wall temperatures as high as 1500/sup 0/F (816/sup 0/C) were observed. Significant variations with respect to time and position were also observed. The CoCrAlY and FeCrAlY alloys appeared to suffer little chemical attack, but both were damaged by what we conclude to be thermally-induced stresses. This mechanism also appears to be a dominant component in the corrosive attack suffered by 310 SS. It was concluded that very thin combustor walls are required in this design to avoid the potentially damaging ''alternating plasticity'' and ''ratcheting'' regimes of cyclic thermal stress. A study of wellbore heat losses from steam injection wells equipped with insulated tubing and conventional (uninsulated) couplings was completed. This study has confirmed that overall wellbore heat loss is substantially higher than expected for good quality tubing with uninsulated couplings if the well bore is wet - an effect attributed to ''wellbore refluxing.'' The temperature at which wellbore refluxing occurs is the boiling point of the annulus water, and is consequently a controllable function of annulus pressure. Reduction of annulus pressure is one means of decreasing the heat loss associated with the refluxing process. Another method is the use of insulated couplings which provided a sufficient thermal resistance to prevent boiling, and hence refluxing, even when totally immersed. Finally, the observation that steady wellbore refluxing can occur without visible steam venting at the wellhead demonstrates that operators should not assume a dry, nonrefluxing annulus based solely on the observed absence of venting. 9 refs., 7 figs.

  15. Numerical simulation of surface-downhole geoelectrical measurements in order to detect brine plumes

    NASA Astrophysics Data System (ADS)

    Bongiovanni, María Victoria; Grünhut, Vivian; Osella, Ana; Tichno, Adrián

    2015-05-01

    A large amount of hydrocarbon reservoirs in the world are in the secondary recovery stage and improving this step in the exploitation of these reservoirs would greatly benefit the oil industry. Secondary recovery involves injecting brine in some wells in order to maintain reservoir pressure. The injected water moves mainly through the channels with higher permeability of the reservoir rock. The identification of these channels would allow the development of technical strategies to close them. In this context, the ability to detect brine flow pathways after injection is a goal of this work. Given the high electrical conductivity of brine, the use of geoelectrical methods can be useful to detect and monitor flow evolution. The limitations in the application of this method are due to the characteristics of the target: a very conductive fluid is usually contained in paths with dimensions that are much smaller than the depth at which it is located. Therefore, our objective is to overcome these constraints in order to find the strategies required to successfully detect and eventually monitor the movement of brine flowing from injection wells. In this work, we studied the feasibility of detecting brine in an oil reservoir with surface-downhole electrical measurements. To achieve this, we designed an electrical model of the reservoir from well data and numerically simulated the forward geoelectrical response to determine the conditions under which the anomaly, i.e., the accumulation of brine, can be identified. Our results show that once the initial location of the brine is known, by installing potential electrodes in a single well the direction of brine migration can be determined, even in unfavorable conditions with relatively few surface measurements. In the case of a well equipped with permanent electrodes, this could be an efficient method to monitor the evolution of the brine plume.

  16. Supervised classification of down-hole physical properties measurements using neural network to predict the lithology

    NASA Astrophysics Data System (ADS)

    Mahmoodi, Omid; Smith, Richard S.; Tinkham, Douglas K.

    2016-01-01

    The reliability of rock-type prediction using down-hole density, gamma ray response, and magnetic susceptibility measurements was evaluated at the Victoria property, Sudbury, ON. A supervised neural network, trained using lithological information from drill hole FNX1168, yields a predictive accuracy of 83% for the training data. Applying the trained network on drill hole FNX1182 resulted in 64% of the rock types being correctly classified when compared with the classification produced by geologists during logging of the core. The homogenous rock types, like quartz diorite, had a high accuracy of classification; while the heterogeneous rock types such as diabase were poorly classified. Overlap between physical properties of rock types caused by heterogeneity or inherent similarity in physical properties of rock types, which were verified by observing the cores, accounts for most of the misclassification. To reduce the misclassification, the network was trained from physical log units in FNX1168 derived from clustering of physical properties measurements. Four physical log units mainly represented four groups of rocks: i) quartz diorite; ii) metabasalt and metagabbro; iii) metasediment and quartzite; and iv) sulfide and diabase. The predictive accuracy in the training process rose to 95%. The trained network then was applied to predicting the physical log units in FNX1182. Given the relationships between physical log units and rock types from FNX1168, the results of physical-log-unit classification in FNX1182 were interpreted from a geological point of view. Although in ideal cases we would like to be able to extract the same classification that a geologist provides, the extraction of physical log units is a more realistic goal. The interpretation of the lithological units from the physical log units can be compared with the geologist's classification and discrepancies or anomalies analyzed in greater detail.

  17. Cracking associated with micrometeoroid impact craters in anodized aluminum alloy clamps on LDEF

    NASA Technical Reports Server (NTRS)

    Murr, Lawrence E.; Niou, Chorng S.; Quinones, Stella; Murr, Kyle S.

    1992-01-01

    The Long Duration Exposure Facility (LDEF) is a reusable hollow-cylindrical satellite sustaining a total of 57 different experiments. The 130 sq m of spacecraft surface area included anodized 6061-T6 Al alloy bay frames and clamps for holding experiment trays in the bay areas. Attention is presently given to the micrometeoroid impact crater features observed on two tray clamps recovered from the LDEF leading-edge locations. It is found that even very subtle surface modifications in structural alloy anodizing can influence micrometeoroid impact crater cracking, notable radial cracking due to the ejecta-rim of the impact craters.

  18. High pressure clamp for electrical measurements up to 8 GPa and temperature down to 77 K

    NASA Astrophysics Data System (ADS)

    Bandyopadhyay, A. K.; Nalini, A. V.; Gopal, E. S. R.; Subramanyam, S. V.

    1980-01-01

    A compact clamp-type high pressure cell for carrying out electrical conductivity measurements on small solid samples of size 1 mm or less at pressures upto 8 GPa (i.e., 80 kbar) and for use down to 77 K has been designed and fabricated. The pressure generated in the sample region has been calibrated at room temperature against the polymorphic phase transitions of Bismuth and Ytterbium. The pressure relaxation of the clamp at low temperatures has been estimated by monitoring the electrical conductivity behavior of lead.

  19. Clamping of RNA with PNA enables targeting of microRNA.

    PubMed

    Ghidini, Alice; Bergquist, Helen; Murtola, Merita; Punga, Tanel; Zain, Rula; Strömberg, Roger

    2016-06-21

    To be able to target microRNAs also at stages where these are in a double stranded or hairpin form we have studied BisPNA designed to clamp the target and give sufficient affinity to allow for strand invasion. We show that BisPNA complexes are more stable with RNA than with DNA. In addition, 24-mer BisPNA (AntimiR) constructs form complexes with a hairpin RNA that is a model of the microRNA miR-376b, suggesting that PNA-clamping may be an effective way of targeting microRNAs. PMID:27203783

  20. Ultrafast spectroscopy of super high frequency mechanical modes of doubly clamped beams

    NASA Astrophysics Data System (ADS)

    Ristow, Oliver; Merklein, Moritz; Grossmann, Martin; Hettich, Mike; Schubert, Martin; Bruchhausen, Axel; Grebing, Jochen; Erbe, Artur; Mounier, Denis; Gusev, Vitalyi; Scheer, Elke; Dekorsy, Thomas; Barretto, Elaine C. S.

    2013-12-01

    We use ultrafast pump-probe spectroscopy to study the mechanical vibrations in the time domain of doubly clamped silicon nitride beams. Beams with two different clamping conditions are investigated. Finite element method calculations are performed to analyse the mode spectra of both structures. By calculating the strain integral on the surface of the resonators, we are able to reproduce the effect of the detection mechanism and identify all the measured modes. We show that our spectroscopy technique combined with our modelling tools allow the investigation of several different modes in the super high frequency range (3-30 GHz) and above, bringing more information about the vibration modes of nanomechanical resonators.