The detailed process and mechanism of colonic motility are still unclear, and colonic motility disorders are associated with numerous clinical diseases. Colonic manometry is considered to the most direct means of eval...The detailed process and mechanism of colonic motility are still unclear, and colonic motility disorders are associated with numerous clinical diseases. Colonic manometry is considered to the most direct means of evaluating colonic peristalsis. Colonic manometry has been studied for more than 30 years;however, the long duration of the examination, high risk of catheterization, huge amount of real-time data, strict catheter sterilization, and high cost of disposable equipment restrict its wide application in clinical practice. Recently, highresolution colonic manometry (HRCM) has rapidly developed into a major technique for obtaining more effective information involved in the physiology and/or pathophysiology of colonic contractile activity in colonic dysmotility patients. This review focuses on colonic motility, manometry, operation, and motor patterns, and the clinical application of HRCM. Furthermore, the limitations, future directions, and potential usefulness of HRCM in the evaluation of clinical treatment effects are also discussed.展开更多
The sedimentary, paleogeomorphological and reservoir characteristics of the Jurassic Yan’an Formation in the southwestern Ordos Basin, northwestern China, were studied by means of casting thin sections, scanning elec...The sedimentary, paleogeomorphological and reservoir characteristics of the Jurassic Yan’an Formation in the southwestern Ordos Basin, northwestern China, were studied by means of casting thin sections, scanning electron microscopy, inclusion analysis and identification of low-amplitude structures. A model for reservoir formation is established, and the controlling effects of sedimentary facies, paleotopography, low-amplitude structures and formation water on oil reservoirs are revealed. There are significant differences in the sedimentary characteristics, structural morphology and paleowater characteristics between the reservoirs above the Yan 10 Member and those in the Yan 9 to Yan 7 Members. The Yan 10 Member contains fluvial sediments, whereas the Yan 9 to Yan 7 members contain delta-plain anastomosing-river deposits. The distribution of high-permeability reservoir is controlled by pre-Jurassic paleogeomorphology and sedimentary facies. Some of these facies exhibit high porosity and high permeability in a lowpermeability background. The main hydrocarbon accumulation period was the late Early Cretaceous, filling was continuous, and the charging strength altered from weak to strong and then from strong to weak. The Yan 10 reservoir is mainly controlled by the paleogeomorphology: hydrocarbons migrated upward at a high speed through the unconformity surface, and accumulated in the favorable traps formed by paleogeomorphic structural units, such as gentle slopes or channel island. Furthermore, groundwater alternation in these areas was relatively stagnant, providing good reservoir preservation conditions. The reservoirs in the Yan 9 and higher members are controlled by the sedimentary facies, lowamplitude structure and paleowater characteristics. Hydrocarbons migrated through the three-dimensional delivery system, influenced by favorable sedimentary facies and high-salinity groundwater, then accumulated in the favorable low-amplitude structural traps that formed during the hydrocarbon production period.展开更多
In this context,a testing system to understand rock fracturing processes induced by different dynamic disturbances under true triaxial compression was developed.The system is mainly composed of a static loading subsys...In this context,a testing system to understand rock fracturing processes induced by different dynamic disturbances under true triaxial compression was developed.The system is mainly composed of a static loading subsystem,a dynamic loading subsystem,a specimen box subsystem,and a data measurement subsystem.The static loading subsystem uses low stiffness loss frame structure technology,which greatly improves the frame stiffness in the three principal stress directions(up to 20 GN/m)and ensures the demand of the disturbance experiment in both the prepeak and postpeak stages.The disturbance loads with frequency of 0e20 Hz and stress level of 0e30 MPa were applied using large flow parallel oil source technology characterized with high heat dissipation efficiency.For the disturbance loads with frequency of 100e500 Hz and stress level of 0e30 MPa,they were realized by using high-frequency and centimeter-per-second-scale low-speed disturbance rod technology.Three rigid self-stabilizing specimen boxes were utilized to provide support for the specimen and deformation sensors,ensuring the stability and accuracy of the data obtained.To verify the performance of the true triaxial test system,disturbance experiments were conducted on granite specimens.The results show that the experimental device satisfies the requirements of original design,with an excellent repeatability and reliable testing results.展开更多
Currently, horizontal well fracturing is indispensable for shale gas development. Due to the variable reservoir formation morphology, the drilling trajectory often deviates from the high-quality reservoir,which increa...Currently, horizontal well fracturing is indispensable for shale gas development. Due to the variable reservoir formation morphology, the drilling trajectory often deviates from the high-quality reservoir,which increases the risk of fracturing. Accurately recognizing low-amplitude structures plays a crucial role in guiding horizontal wells. However, existing methods have low recognition accuracy, and are difficult to meet actual production demand. In order to improve the drilling encounter rate of high-quality reservoirs, we propose a method for fine recognition of low-amplitude structures based on the non-subsampled contourlet transform(NSCT). Firstly, the seismic structural data are analyzed at multiple scales and directions using the NSCT and decomposed into low-frequency and high-frequency structural components. Then, the signal of each component is reconstructed to eliminate the low-frequency background of the structure, highlight the structure and texture information, and recognize the low-amplitude structure from it. Finally, we combined the drilled horizontal wells to verify the low-amplitude structural recognition results. Taking a study area in the west Sichuan Basin block as an example, we demonstrate the fine identification of low-amplitude structures based on NSCT. By combining the variation characteristics of logging curves, such as organic carbon content(TOC), natural gamma value(GR), etc., the real structure type is verified and determined, and the false structures in the recognition results are checked. The proposed method can provide reliable information on low-amplitude structures for optimizing the trajectory of horizontal wells. Compared with identification methods based on traditional wavelet transform and curvelet transform, NSCT enhances the local features of low-amplitude structures and achieves finer mapping of low-amplitude structures, showing promise for application.展开更多
Based on drilling, logging, test production and dynamic monitoring data, the control effects of low-amplitude structure on hydrocarbon accumulation and development performance of ultra-low permeability reservoirs were...Based on drilling, logging, test production and dynamic monitoring data, the control effects of low-amplitude structure on hydrocarbon accumulation and development performance of ultra-low permeability reservoirs were discussed by using the methods of dense well pattern, multi-factor geological modeling, macro and micro analysis and static and dynamic analysis. The results show that the low-amplitude structure always had a significant control and influence on the distribution and accumulation of original hydrocarbon and water and the evolution trend of water flooding performance in ultra-low permeability reservoirs, and it was not only the direction of oil and gas migration, but also a favorable place for relative accumulation of oil and gas. The controlling effect of low-amplitude structure on ultra-low permeability reservoir mainly depended on its tectonic amplitude and scale;the larger the tectonic amplitude and scale, and the higher the tectonic position of the low amplitude structure, the better the reservoir characteristic parameters, oil and gas enrichment degree and development effect, and the larger the spatial scope it controlled and influenced;water cut and oil well output always fluctuated orderly with the height of the low-amplitude structure;the dynamic response of waterflooding was closely related to the relative structural position of the injection and production wells;the injected water always advanced to the low-lying area of the structure first and then moved up to the high-lying area of the structure gradually;with the continuous expansion of the flooded area, part of the oil and gas in the low-lying part of the structure was forced to be distributed to the high part of the structure, resulting in a new oil and gas enrichment, so that the dynamic reserves of oil wells in the high part increased, and the production capacity remained stable.展开更多
Varying degree of velocity anomalies has been appeared in Shijiutuo uplift in Bohai Sea,which is mainly demonstrated in the inconsistent between seismic interpretation and the actual drilling depth.In this paper, QHD3...Varying degree of velocity anomalies has been appeared in Shijiutuo uplift in Bohai Sea,which is mainly demonstrated in the inconsistent between seismic interpretation and the actual drilling depth.In this paper, QHD33-1S area is taken as the example.First of all,the main reason that causes the velocity anomaly phenomena is the effect of sand-formation ratio by forward model analysis,and then technical approaches to improve the accuracy of the velocity field and the degree of understanding of anomalies are further explored,resulting in more precise determination of horizontal variation trend of the velocity in QHD33-1S area.Consequences of actual applications indicate that through the accurate analysis of the velocity anomaly,we can not only realize the fine description of low-amplitude structure,but also the effective prediction of the hydrocarbon-bearing properties of the reservoir.Meanwhile,the results also have a certain significance for the other low-amplitude structures in Bohai Sea.展开更多
Thermoacoustic refrigerator （TAR） converts acoustic waves into heat without any moving parts. The study presented here aims to optimize the parameters like frequency, stack position, stack length, and plate spacing ...Thermoacoustic refrigerator （TAR） converts acoustic waves into heat without any moving parts. The study presented here aims to optimize the parameters like frequency, stack position, stack length, and plate spacing involving in designing TAR using the Response Surface Methodology （RSM）. A mathematical model is developed using the RSM based on the results obtained from DeltaEC software. For desired temperature difference of 40 K, optimized parameters suggested by the RSM are the frequency 254 Hz, stack position 0.108 m, stack length 0.08 m, and plate spacing 0.0005 m. The experiments were conducted with optimized parameters and simulations were performed using the Design Environment for Low-amplitude ThermoAcoustic Energy Conversion （DeltaEC） which showed similar results.展开更多
文摘The detailed process and mechanism of colonic motility are still unclear, and colonic motility disorders are associated with numerous clinical diseases. Colonic manometry is considered to the most direct means of evaluating colonic peristalsis. Colonic manometry has been studied for more than 30 years;however, the long duration of the examination, high risk of catheterization, huge amount of real-time data, strict catheter sterilization, and high cost of disposable equipment restrict its wide application in clinical practice. Recently, highresolution colonic manometry (HRCM) has rapidly developed into a major technique for obtaining more effective information involved in the physiology and/or pathophysiology of colonic contractile activity in colonic dysmotility patients. This review focuses on colonic motility, manometry, operation, and motor patterns, and the clinical application of HRCM. Furthermore, the limitations, future directions, and potential usefulness of HRCM in the evaluation of clinical treatment effects are also discussed.
基金National Science and Technology Major Projects(Grant No.2016ZX05050,2017ZX05001002-008)CNPC Major Projects(Grant No.2016E-0501).
文摘The sedimentary, paleogeomorphological and reservoir characteristics of the Jurassic Yan’an Formation in the southwestern Ordos Basin, northwestern China, were studied by means of casting thin sections, scanning electron microscopy, inclusion analysis and identification of low-amplitude structures. A model for reservoir formation is established, and the controlling effects of sedimentary facies, paleotopography, low-amplitude structures and formation water on oil reservoirs are revealed. There are significant differences in the sedimentary characteristics, structural morphology and paleowater characteristics between the reservoirs above the Yan 10 Member and those in the Yan 9 to Yan 7 Members. The Yan 10 Member contains fluvial sediments, whereas the Yan 9 to Yan 7 members contain delta-plain anastomosing-river deposits. The distribution of high-permeability reservoir is controlled by pre-Jurassic paleogeomorphology and sedimentary facies. Some of these facies exhibit high porosity and high permeability in a lowpermeability background. The main hydrocarbon accumulation period was the late Early Cretaceous, filling was continuous, and the charging strength altered from weak to strong and then from strong to weak. The Yan 10 reservoir is mainly controlled by the paleogeomorphology: hydrocarbons migrated upward at a high speed through the unconformity surface, and accumulated in the favorable traps formed by paleogeomorphic structural units, such as gentle slopes or channel island. Furthermore, groundwater alternation in these areas was relatively stagnant, providing good reservoir preservation conditions. The reservoirs in the Yan 9 and higher members are controlled by the sedimentary facies, lowamplitude structure and paleowater characteristics. Hydrocarbons migrated through the three-dimensional delivery system, influenced by favorable sedimentary facies and high-salinity groundwater, then accumulated in the favorable low-amplitude structural traps that formed during the hydrocarbon production period.
基金This study was financially supported by the National Natural Science Foundation of China(Grant No.51839003),for which we are grateful.
文摘In this context,a testing system to understand rock fracturing processes induced by different dynamic disturbances under true triaxial compression was developed.The system is mainly composed of a static loading subsystem,a dynamic loading subsystem,a specimen box subsystem,and a data measurement subsystem.The static loading subsystem uses low stiffness loss frame structure technology,which greatly improves the frame stiffness in the three principal stress directions(up to 20 GN/m)and ensures the demand of the disturbance experiment in both the prepeak and postpeak stages.The disturbance loads with frequency of 0e20 Hz and stress level of 0e30 MPa were applied using large flow parallel oil source technology characterized with high heat dissipation efficiency.For the disturbance loads with frequency of 100e500 Hz and stress level of 0e30 MPa,they were realized by using high-frequency and centimeter-per-second-scale low-speed disturbance rod technology.Three rigid self-stabilizing specimen boxes were utilized to provide support for the specimen and deformation sensors,ensuring the stability and accuracy of the data obtained.To verify the performance of the true triaxial test system,disturbance experiments were conducted on granite specimens.The results show that the experimental device satisfies the requirements of original design,with an excellent repeatability and reliable testing results.
基金supported by Sichuan Science and Technology Program under Grant 2024NSFSC1984 and Grant 2024NSFSC1990。
文摘Currently, horizontal well fracturing is indispensable for shale gas development. Due to the variable reservoir formation morphology, the drilling trajectory often deviates from the high-quality reservoir,which increases the risk of fracturing. Accurately recognizing low-amplitude structures plays a crucial role in guiding horizontal wells. However, existing methods have low recognition accuracy, and are difficult to meet actual production demand. In order to improve the drilling encounter rate of high-quality reservoirs, we propose a method for fine recognition of low-amplitude structures based on the non-subsampled contourlet transform(NSCT). Firstly, the seismic structural data are analyzed at multiple scales and directions using the NSCT and decomposed into low-frequency and high-frequency structural components. Then, the signal of each component is reconstructed to eliminate the low-frequency background of the structure, highlight the structure and texture information, and recognize the low-amplitude structure from it. Finally, we combined the drilled horizontal wells to verify the low-amplitude structural recognition results. Taking a study area in the west Sichuan Basin block as an example, we demonstrate the fine identification of low-amplitude structures based on NSCT. By combining the variation characteristics of logging curves, such as organic carbon content(TOC), natural gamma value(GR), etc., the real structure type is verified and determined, and the false structures in the recognition results are checked. The proposed method can provide reliable information on low-amplitude structures for optimizing the trajectory of horizontal wells. Compared with identification methods based on traditional wavelet transform and curvelet transform, NSCT enhances the local features of low-amplitude structures and achieves finer mapping of low-amplitude structures, showing promise for application.
基金Supported by Open Fund(PLC20190203)of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology)the Natural Science Foundation of Shaanxi Province,China(2006Z07,2010JM5003)Youth Science and Technology Innovation Fund Project of Xi’an Petroleum University(2012BS010)
文摘Based on drilling, logging, test production and dynamic monitoring data, the control effects of low-amplitude structure on hydrocarbon accumulation and development performance of ultra-low permeability reservoirs were discussed by using the methods of dense well pattern, multi-factor geological modeling, macro and micro analysis and static and dynamic analysis. The results show that the low-amplitude structure always had a significant control and influence on the distribution and accumulation of original hydrocarbon and water and the evolution trend of water flooding performance in ultra-low permeability reservoirs, and it was not only the direction of oil and gas migration, but also a favorable place for relative accumulation of oil and gas. The controlling effect of low-amplitude structure on ultra-low permeability reservoir mainly depended on its tectonic amplitude and scale;the larger the tectonic amplitude and scale, and the higher the tectonic position of the low amplitude structure, the better the reservoir characteristic parameters, oil and gas enrichment degree and development effect, and the larger the spatial scope it controlled and influenced;water cut and oil well output always fluctuated orderly with the height of the low-amplitude structure;the dynamic response of waterflooding was closely related to the relative structural position of the injection and production wells;the injected water always advanced to the low-lying area of the structure first and then moved up to the high-lying area of the structure gradually;with the continuous expansion of the flooded area, part of the oil and gas in the low-lying part of the structure was forced to be distributed to the high part of the structure, resulting in a new oil and gas enrichment, so that the dynamic reserves of oil wells in the high part increased, and the production capacity remained stable.
文摘Varying degree of velocity anomalies has been appeared in Shijiutuo uplift in Bohai Sea,which is mainly demonstrated in the inconsistent between seismic interpretation and the actual drilling depth.In this paper, QHD33-1S area is taken as the example.First of all,the main reason that causes the velocity anomaly phenomena is the effect of sand-formation ratio by forward model analysis,and then technical approaches to improve the accuracy of the velocity field and the degree of understanding of anomalies are further explored,resulting in more precise determination of horizontal variation trend of the velocity in QHD33-1S area.Consequences of actual applications indicate that through the accurate analysis of the velocity anomaly,we can not only realize the fine description of low-amplitude structure,but also the effective prediction of the hydrocarbon-bearing properties of the reservoir.Meanwhile,the results also have a certain significance for the other low-amplitude structures in Bohai Sea.
基金financially supported by student research fund of National Institute of Technology,Tiruchirapalli–620 015, India
文摘Thermoacoustic refrigerator （TAR） converts acoustic waves into heat without any moving parts. The study presented here aims to optimize the parameters like frequency, stack position, stack length, and plate spacing involving in designing TAR using the Response Surface Methodology （RSM）. A mathematical model is developed using the RSM based on the results obtained from DeltaEC software. For desired temperature difference of 40 K, optimized parameters suggested by the RSM are the frequency 254 Hz, stack position 0.108 m, stack length 0.08 m, and plate spacing 0.0005 m. The experiments were conducted with optimized parameters and simulations were performed using the Design Environment for Low-amplitude ThermoAcoustic Energy Conversion （DeltaEC） which showed similar results.
