The Experts below are selected from a list of 78651 Experts worldwide ranked by ideXlab platform
Ali Bashir Biderkab - One of the best experts on this subject based on the ideXlab platform.
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Visual Observation of gas hydrate formation and dissociation in synthetic porous media by means of glass micromodels
Geology, 2001Co-Authors: Bahman Tohidi, Ross Anderson, Ben Clennell, Rod Burgass, Ali Bashir BiderkabAbstract:Visual Observation of gas hydrates at the microscopic scale in synthetic porous media provides unequivocal Visual evidence that clathrates can form in systems without the presence of a free-gas phase. Hydrates were formed from a soluble liquid hydrate former (tetrahydrofuran, C 4 H 8 O), from free gas (CH 4 ), and from dissolved gas (CO 2 ). Clathrates were found to form within the center of pore spaces, rather than on grain surfaces. Cementation of grains only occurred in regions of a small grain size, or where a large proportion of pore space was filled with hydrate. However, even at high clathrate saturations, a thin film of free water persisted on grain surfaces. The results have important implications for the potential cementing effect of hydrates on sediments, and thus for sediment permeability, slope stability, and seismic interpretation of hydrate-bearing sediments.
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Visual Observation of gas hydrate formation in glass micromodels
63rd EAGE Conference and Exhibition, 2001Co-Authors: Ross Anderson, Ali Bashir Biderkab, Bahman Tohidi, Ben ClennellAbstract:P568 Visual Observation OF GAS HYDRATE FORMATION IN GLASS MICROMODELS 1 1 1 1 2 ROSS ANDERSON A. B. BIDERKAB BAHMAN TOHIDI and M. BEN CLENNELL 1 Centre for Gas Hydrate Research Department of Petroleum Engineering Heriot-Watt University Edinburgh EH14 4AS UK 2 Centro de Pesquisa em Geofsica e Geologia – IGEO Universidade Federal da Bahia SUMMARY: A glass micromodel rig had been commissioned for use in the Visual Observation of gas hydrate formation and dissociation in porous media. The rig provides a unique opportunity for direct Visual Observation of phase behaviour at the microscopic scale. We report results on
Ben Clennell - One of the best experts on this subject based on the ideXlab platform.
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Visual Observation of gas hydrate formation and dissociation in synthetic porous media by means of glass micromodels
Geology, 2001Co-Authors: Bahman Tohidi, Ross Anderson, Ben Clennell, Rod Burgass, Ali Bashir BiderkabAbstract:Visual Observation of gas hydrates at the microscopic scale in synthetic porous media provides unequivocal Visual evidence that clathrates can form in systems without the presence of a free-gas phase. Hydrates were formed from a soluble liquid hydrate former (tetrahydrofuran, C 4 H 8 O), from free gas (CH 4 ), and from dissolved gas (CO 2 ). Clathrates were found to form within the center of pore spaces, rather than on grain surfaces. Cementation of grains only occurred in regions of a small grain size, or where a large proportion of pore space was filled with hydrate. However, even at high clathrate saturations, a thin film of free water persisted on grain surfaces. The results have important implications for the potential cementing effect of hydrates on sediments, and thus for sediment permeability, slope stability, and seismic interpretation of hydrate-bearing sediments.
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Visual Observation of gas hydrate formation in glass micromodels
63rd EAGE Conference and Exhibition, 2001Co-Authors: Ross Anderson, Ali Bashir Biderkab, Bahman Tohidi, Ben ClennellAbstract:P568 Visual Observation OF GAS HYDRATE FORMATION IN GLASS MICROMODELS 1 1 1 1 2 ROSS ANDERSON A. B. BIDERKAB BAHMAN TOHIDI and M. BEN CLENNELL 1 Centre for Gas Hydrate Research Department of Petroleum Engineering Heriot-Watt University Edinburgh EH14 4AS UK 2 Centro de Pesquisa em Geofsica e Geologia – IGEO Universidade Federal da Bahia SUMMARY: A glass micromodel rig had been commissioned for use in the Visual Observation of gas hydrate formation and dissociation in porous media. The rig provides a unique opportunity for direct Visual Observation of phase behaviour at the microscopic scale. We report results on
Bahman Tohidi - One of the best experts on this subject based on the ideXlab platform.
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Visual Observation of gas hydrate formation and dissociation in synthetic porous media by means of glass micromodels
Geology, 2001Co-Authors: Bahman Tohidi, Ross Anderson, Ben Clennell, Rod Burgass, Ali Bashir BiderkabAbstract:Visual Observation of gas hydrates at the microscopic scale in synthetic porous media provides unequivocal Visual evidence that clathrates can form in systems without the presence of a free-gas phase. Hydrates were formed from a soluble liquid hydrate former (tetrahydrofuran, C 4 H 8 O), from free gas (CH 4 ), and from dissolved gas (CO 2 ). Clathrates were found to form within the center of pore spaces, rather than on grain surfaces. Cementation of grains only occurred in regions of a small grain size, or where a large proportion of pore space was filled with hydrate. However, even at high clathrate saturations, a thin film of free water persisted on grain surfaces. The results have important implications for the potential cementing effect of hydrates on sediments, and thus for sediment permeability, slope stability, and seismic interpretation of hydrate-bearing sediments.
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Visual Observation of gas hydrate formation in glass micromodels
63rd EAGE Conference and Exhibition, 2001Co-Authors: Ross Anderson, Ali Bashir Biderkab, Bahman Tohidi, Ben ClennellAbstract:P568 Visual Observation OF GAS HYDRATE FORMATION IN GLASS MICROMODELS 1 1 1 1 2 ROSS ANDERSON A. B. BIDERKAB BAHMAN TOHIDI and M. BEN CLENNELL 1 Centre for Gas Hydrate Research Department of Petroleum Engineering Heriot-Watt University Edinburgh EH14 4AS UK 2 Centro de Pesquisa em Geofsica e Geologia – IGEO Universidade Federal da Bahia SUMMARY: A glass micromodel rig had been commissioned for use in the Visual Observation of gas hydrate formation and dissociation in porous media. The rig provides a unique opportunity for direct Visual Observation of phase behaviour at the microscopic scale. We report results on
Ross Anderson - One of the best experts on this subject based on the ideXlab platform.
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Visual Observation of gas hydrate formation and dissociation in synthetic porous media by means of glass micromodels
Geology, 2001Co-Authors: Bahman Tohidi, Ross Anderson, Ben Clennell, Rod Burgass, Ali Bashir BiderkabAbstract:Visual Observation of gas hydrates at the microscopic scale in synthetic porous media provides unequivocal Visual evidence that clathrates can form in systems without the presence of a free-gas phase. Hydrates were formed from a soluble liquid hydrate former (tetrahydrofuran, C 4 H 8 O), from free gas (CH 4 ), and from dissolved gas (CO 2 ). Clathrates were found to form within the center of pore spaces, rather than on grain surfaces. Cementation of grains only occurred in regions of a small grain size, or where a large proportion of pore space was filled with hydrate. However, even at high clathrate saturations, a thin film of free water persisted on grain surfaces. The results have important implications for the potential cementing effect of hydrates on sediments, and thus for sediment permeability, slope stability, and seismic interpretation of hydrate-bearing sediments.
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Visual Observation of gas hydrate formation in glass micromodels
63rd EAGE Conference and Exhibition, 2001Co-Authors: Ross Anderson, Ali Bashir Biderkab, Bahman Tohidi, Ben ClennellAbstract:P568 Visual Observation OF GAS HYDRATE FORMATION IN GLASS MICROMODELS 1 1 1 1 2 ROSS ANDERSON A. B. BIDERKAB BAHMAN TOHIDI and M. BEN CLENNELL 1 Centre for Gas Hydrate Research Department of Petroleum Engineering Heriot-Watt University Edinburgh EH14 4AS UK 2 Centro de Pesquisa em Geofsica e Geologia – IGEO Universidade Federal da Bahia SUMMARY: A glass micromodel rig had been commissioned for use in the Visual Observation of gas hydrate formation and dissociation in porous media. The rig provides a unique opportunity for direct Visual Observation of phase behaviour at the microscopic scale. We report results on
Marcia I Endres - One of the best experts on this subject based on the ideXlab platform.
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technical note validation of an ear tag accelerometer sensor to determine rumination eating and activity behaviors of grazing dairy cattle
Journal of Dairy Science, 2017Co-Authors: G M Pereira, Bradley J Heins, Marcia I EndresAbstract:ABSTRACT The objective of this study was to validate an ear-tag accelerometer sensor (CowManager SensOor, Agis Automatisering BV, Harmelen, the Netherlands) using direct Visual Observations in a grazing dairy herd. Lactating crossbred cows (n = 24) were used for this experiment at the University of Minnesota West Central Research and Outreach Center grazing dairy (Morris, MN) during the summer of 2016. A single trained observer recorded behavior every minute for 6 h for each cow (24 cows × 6 h=144 h of Observation total). Direct Visual Observation was compared with sensor data during August and September 2016. The sensor detected and identified ear and head movements, and through algorithms the sensor classified each minute as one of the following behaviors: rumination, eating, not active, active, and high active. A 2-sided t -test was conducted with PROC TTEST of SAS (SAS Institute Inc., Cary, NC) to compare the percentage of time each cow's behavior was recorded by direct Visual Observation and sensor data. For total recorded time, the percentage of time of direct Visual Observation compared with sensor data was 17.9 and 19.1% for rumination, 52.8 and 51.9% for eating, 17.4 and 11.9% for not active, and 7.9 and 21.1% for active. Pearson correlations (PROC CORR of SAS) were used to evaluate associations between direct Visual Observations and sensor data. Furthermore, concordance correlation coefficient (CCC), bias correction factors, location shift, and scale shift (epiR package of R version 3.3.1; R Foundation for Statistical Computing, Vienna, Austria) were calculated to provide a measure of accuracy and precision. Correlations between Visual Observations for all 4 behaviors were highly to weakly correlated (rumination: r=0.72, CCC=0.71; eating: r=0.88, CCC=0.88; not active: r=0.65, CCC=0.52; and active: r=0.20, CCC=0.19) compared with sensor data. The results suggest that the sensor accurately monitors rumination and eating behavior of grazing dairy cattle. However, active behaviors may be more difficult for the sensor to record than others.
