In intracratnoic basins, the effect of strike-slip faults on sedimentary microfacies is generally underestimated due to their small scale. Based on the integration of core, well logs, and three-dimensional seismic dat...In intracratnoic basins, the effect of strike-slip faults on sedimentary microfacies is generally underestimated due to their small scale. Based on the integration of core, well logs, and three-dimensional seismic data, this study presents a comprehensive analysis of the Permian carbonate platform and strike-slip faults in the southwestern Kaijiang-Liangping trough of the Sichuan Basin. The relationship between strike-slip faults and Permian carbonate microfacies is investigated. The results reveals the existence of a NW-trending strike-slip fault zone along the platform margin, exhibiting clear segmentation. The western side of the study area exhibits a rimmed platform margin characterized by type I reefs, which corresponds to the presence of a large-scale strike-slip fault zone. In contrast, the eastern side is characterized by a norimmed and weak rimmed platform margin, accompanied by type II reefs, which align with smaller strike-slip fault zones. It was found that the strike-slip fault had some effects on the platform and reef-shoal complex of the Permain Changxing Formation. First, the platform was divided by strike-slip fault into three segments to show rimmed, week rimmed and norimmed platform. Second, reef-shoal complex devolped along the faulted high position in the strike-slip fault zone, and separated by faulted depression. Third, strike-slip faults can offset or migrated the reef-shoal complex and platform margin. Additionally, the thickness of the platform margin varies across strike-slip fault zone, which is related to the activity of strike-slip faults. The strike-slip faults affect the microfacies by controlling the pre-depositional paleotopography. This case suggests that the strike-slip faults play a crucial role in the diversity and distribution of carbonate microfacies in the intracratonic basin.展开更多
Inconel 718,a nickel,chrome and iron alloy,has special advantages,such as high-temperature strength,thermal resistance and corrosion resistance,which facilitate wide usage in the aerospace industry,especially in the h...Inconel 718,a nickel,chrome and iron alloy,has special advantages,such as high-temperature strength,thermal resistance and corrosion resistance,which facilitate wide usage in the aerospace industry,especially in the hot sections of gas turbine engines.However,machining this alloy is correlated closely with the material’s inherent properties such as excellent combination of strength,hardness and toughness,low thermal conductivity and the tendency to adhere to cutting tools.This nickel alloy also contains inclusions of hard abrasive carbide particles that lead to work-hardening of the workpiece material and thus abrasive wear of the cutting tool.That is,the machining of Inconel 718 is always influenced by high mechanical and thermal loads.This article reviews the chip formation mechanism of Inconel 718.One of the main characteristics in machining of Inconel 718 is that it will produce serrated or segmented chips in a wide range of cutting speeds and feeds.Existing studies show that the chip serration or segmentation by shear localization affects the machined surface integrity,and also contributes to the chip’s evacuation and the automation of machining operations.Thus,research conclusion indicates that the serrated or segmented chip phenomenon is desirable in reducing the level of cutting force,and detailed analysis of models and approaches to understand the chip formation mechanism of Inconel 718 is vital for machining this alloy effectively and efficiently.Therefore,this article presents some summaries on the models and approaches on the chip formation in machining of Inconel 718.展开更多
Based on analysis of field survey, drilling and seismic data, the formation and evolution process of Deyang-Anyue erosion rift trough in Sichuan Basin was reconstructed, and exploration areas were divided and evaluate...Based on analysis of field survey, drilling and seismic data, the formation and evolution process of Deyang-Anyue erosion rift trough in Sichuan Basin was reconstructed, and exploration areas were divided and evaluated. The results show that:(1) Dengying Formation in and around Deyang-Anyue erosion rift trough varies widely in sedimentary characteristics. The Dengying Formation in the northern part of the erosion rift trough developed deep-water sediments, the Dengying Formation in the northern part of the basin varied gradually from basin to slope, platform margin, and restricted platform, and the Dengying Formation in the middle and southern parts of the trough developed carbonate platform facies.(2) Deyang-Anyue erosion rift trough is formed by extensional rift and karst erosion jointly, the north section of the erosion rift trough is mainly the product of tensile rift, while the middle and south sections are formed by erosion in multi-episodes of Tongwan period.(3) Based on the segmented origins of the erosion rift trough, Dengying Formation in and around it is divided into three exploration fields: lithologic mound and beach bodies at the northern platform margin of the basin, karst mound and beach bodies in the central platform, and karst residual mounds in the central southern trough of the basin, among them, the karst residual mounds in the central southern trough of the basin are a new frontier for natural gas exploration in the basin, and the lithologic mound and beach bodies at the northern platform margin are a new position for increasing the reserves of trillions of cubic meters of natural gas resources in the basin.展开更多
The volume of hippocampal subfields is closely related with early diagnosis of Alzheimer's disease.Due to the anatomical complexity of hippocampal subfields,automatic segmentation merely on the content of MR image...The volume of hippocampal subfields is closely related with early diagnosis of Alzheimer's disease.Due to the anatomical complexity of hippocampal subfields,automatic segmentation merely on the content of MR images is extremely difficult.We presented a method which combines multi-atlas image segmentation with extreme learning machine based bias detection and correction technique to achieve a fully automatic segmentation of hippocampal subfields.Symmetric diffeomorphic registration driven by symmetric mutual information energy was implemented in atlas registration,which allows multi-modal image registration and accelerates execution time.An exponential function based label fusion strategy was proposed for the normalized similarity measure case in segmentation combination,which yields better combination accuracy.The test results show that this method is effective,especially for the larger subfields with an overlap of more than 80%,which is competitive with the current methods and is of potential clinical significance.展开更多
A series of PCL/MDI/BDO segmented polyurethanes have been synthesized by two-step method in solution.The hard segment content ranges from 10% to 48% by weight, and the molecular weight of PCL diols is 1500. Hard segme...A series of PCL/MDI/BDO segmented polyurethanes have been synthesized by two-step method in solution.The hard segment content ranges from 10% to 48% by weight, and the molecular weight of PCL diols is 1500. Hard segment spherulites have been observed in compression molded specimens of all of the samples except the one of the lowest hard segment content. The difficulty in sphernlite formation was explained as only in a small temperature range,the microphase separation rate may be faster than the crystallization rate and all these processes are very slow due to the hydrogen bonding between hard and soft segments and the interactions between hard segments themselves. PCL soft segments of molecular weight 1500 is still crystallizable and may form different crystalline superstructures.展开更多
In this study,we aim to clarify the structural characteristics and deformation process of the Changning anticline.We carefully interpret 38 two-dimensional(2D)seismic profiles in the study area and establish three-dim...In this study,we aim to clarify the structural characteristics and deformation process of the Changning anticline.We carefully interpret 38 two-dimensional(2D)seismic profiles in the study area and establish three-dimensional(3D)geometric and quantitative kinematic models of the Changning anticline.This study shows that the basement fault controls the formation of the Changning anticline.The fault slope of the main fault in the basement shows’steep in the upper and gentle in the lower’structural characteristics vertically,possessing obvious segmentary characteristics transversely and presents the overall characteristics of’steep in the east and gentle in the west’.Further analysis shows that the Changning anticline proceeds west and terminates at the boundary defined by current surface features but gradually disappears westward across the Mt.Huaying fault zone.Furthermore,we identified that deformation of the Changning anticline began during the early Yanshanian movement period.Under compressional stress from the southeast,the anticline slid forward along the basement fault until the end of the Yanshanian movement period,when the dominant WNW-ESE structure gradually emerged.Since the Himalayan movement period,a series of NE-trending structures have been formed in the anticline,owing to multi-directional compressive stress.展开更多
基金partly supported by the National Natural Science Foundation of China (Grant No. 4224100017)Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance (Grant No.2020CX010300)。
文摘In intracratnoic basins, the effect of strike-slip faults on sedimentary microfacies is generally underestimated due to their small scale. Based on the integration of core, well logs, and three-dimensional seismic data, this study presents a comprehensive analysis of the Permian carbonate platform and strike-slip faults in the southwestern Kaijiang-Liangping trough of the Sichuan Basin. The relationship between strike-slip faults and Permian carbonate microfacies is investigated. The results reveals the existence of a NW-trending strike-slip fault zone along the platform margin, exhibiting clear segmentation. The western side of the study area exhibits a rimmed platform margin characterized by type I reefs, which corresponds to the presence of a large-scale strike-slip fault zone. In contrast, the eastern side is characterized by a norimmed and weak rimmed platform margin, accompanied by type II reefs, which align with smaller strike-slip fault zones. It was found that the strike-slip fault had some effects on the platform and reef-shoal complex of the Permain Changxing Formation. First, the platform was divided by strike-slip fault into three segments to show rimmed, week rimmed and norimmed platform. Second, reef-shoal complex devolped along the faulted high position in the strike-slip fault zone, and separated by faulted depression. Third, strike-slip faults can offset or migrated the reef-shoal complex and platform margin. Additionally, the thickness of the platform margin varies across strike-slip fault zone, which is related to the activity of strike-slip faults. The strike-slip faults affect the microfacies by controlling the pre-depositional paleotopography. This case suggests that the strike-slip faults play a crucial role in the diversity and distribution of carbonate microfacies in the intracratonic basin.
基金Supported by National Natural Science Foundation of China(Grant Nos.51975481 and 51675440)Fundamental Research Funds for the Central Universities(Grant No.3102020ZX004).
文摘Inconel 718,a nickel,chrome and iron alloy,has special advantages,such as high-temperature strength,thermal resistance and corrosion resistance,which facilitate wide usage in the aerospace industry,especially in the hot sections of gas turbine engines.However,machining this alloy is correlated closely with the material’s inherent properties such as excellent combination of strength,hardness and toughness,low thermal conductivity and the tendency to adhere to cutting tools.This nickel alloy also contains inclusions of hard abrasive carbide particles that lead to work-hardening of the workpiece material and thus abrasive wear of the cutting tool.That is,the machining of Inconel 718 is always influenced by high mechanical and thermal loads.This article reviews the chip formation mechanism of Inconel 718.One of the main characteristics in machining of Inconel 718 is that it will produce serrated or segmented chips in a wide range of cutting speeds and feeds.Existing studies show that the chip serration or segmentation by shear localization affects the machined surface integrity,and also contributes to the chip’s evacuation and the automation of machining operations.Thus,research conclusion indicates that the serrated or segmented chip phenomenon is desirable in reducing the level of cutting force,and detailed analysis of models and approaches to understand the chip formation mechanism of Inconel 718 is vital for machining this alloy effectively and efficiently.Therefore,this article presents some summaries on the models and approaches on the chip formation in machining of Inconel 718.
基金Supported by the National Key Research and Development Program of China (2017YFC0603106)Project of Science and Technology Department of PetroChina Southwest Oil and Gas Field Company (20200301-01)。
文摘Based on analysis of field survey, drilling and seismic data, the formation and evolution process of Deyang-Anyue erosion rift trough in Sichuan Basin was reconstructed, and exploration areas were divided and evaluated. The results show that:(1) Dengying Formation in and around Deyang-Anyue erosion rift trough varies widely in sedimentary characteristics. The Dengying Formation in the northern part of the erosion rift trough developed deep-water sediments, the Dengying Formation in the northern part of the basin varied gradually from basin to slope, platform margin, and restricted platform, and the Dengying Formation in the middle and southern parts of the trough developed carbonate platform facies.(2) Deyang-Anyue erosion rift trough is formed by extensional rift and karst erosion jointly, the north section of the erosion rift trough is mainly the product of tensile rift, while the middle and south sections are formed by erosion in multi-episodes of Tongwan period.(3) Based on the segmented origins of the erosion rift trough, Dengying Formation in and around it is divided into three exploration fields: lithologic mound and beach bodies at the northern platform margin of the basin, karst mound and beach bodies in the central platform, and karst residual mounds in the central southern trough of the basin, among them, the karst residual mounds in the central southern trough of the basin are a new frontier for natural gas exploration in the basin, and the lithologic mound and beach bodies at the northern platform margin are a new position for increasing the reserves of trillions of cubic meters of natural gas resources in the basin.
基金Supported by the National Natural Science Foundation of China(Nos.60971133,61271112)
文摘The volume of hippocampal subfields is closely related with early diagnosis of Alzheimer's disease.Due to the anatomical complexity of hippocampal subfields,automatic segmentation merely on the content of MR images is extremely difficult.We presented a method which combines multi-atlas image segmentation with extreme learning machine based bias detection and correction technique to achieve a fully automatic segmentation of hippocampal subfields.Symmetric diffeomorphic registration driven by symmetric mutual information energy was implemented in atlas registration,which allows multi-modal image registration and accelerates execution time.An exponential function based label fusion strategy was proposed for the normalized similarity measure case in segmentation combination,which yields better combination accuracy.The test results show that this method is effective,especially for the larger subfields with an overlap of more than 80%,which is competitive with the current methods and is of potential clinical significance.
文摘A series of PCL/MDI/BDO segmented polyurethanes have been synthesized by two-step method in solution.The hard segment content ranges from 10% to 48% by weight, and the molecular weight of PCL diols is 1500. Hard segment spherulites have been observed in compression molded specimens of all of the samples except the one of the lowest hard segment content. The difficulty in sphernlite formation was explained as only in a small temperature range,the microphase separation rate may be faster than the crystallization rate and all these processes are very slow due to the hydrogen bonding between hard and soft segments and the interactions between hard segments themselves. PCL soft segments of molecular weight 1500 is still crystallizable and may form different crystalline superstructures.
基金supported by the National Natural Science Foundation of China(Grant No.U19B6003-01)。
文摘In this study,we aim to clarify the structural characteristics and deformation process of the Changning anticline.We carefully interpret 38 two-dimensional(2D)seismic profiles in the study area and establish three-dimensional(3D)geometric and quantitative kinematic models of the Changning anticline.This study shows that the basement fault controls the formation of the Changning anticline.The fault slope of the main fault in the basement shows’steep in the upper and gentle in the lower’structural characteristics vertically,possessing obvious segmentary characteristics transversely and presents the overall characteristics of’steep in the east and gentle in the west’.Further analysis shows that the Changning anticline proceeds west and terminates at the boundary defined by current surface features but gradually disappears westward across the Mt.Huaying fault zone.Furthermore,we identified that deformation of the Changning anticline began during the early Yanshanian movement period.Under compressional stress from the southeast,the anticline slid forward along the basement fault until the end of the Yanshanian movement period,when the dominant WNW-ESE structure gradually emerged.Since the Himalayan movement period,a series of NE-trending structures have been formed in the anticline,owing to multi-directional compressive stress.