A novel temperature-preserved core chamber designed for depths exceeding 5000 m has been developed to enhance the scientific understanding of deep oil and gas reservoirs.This temperature-preserved core chamber employs...A novel temperature-preserved core chamber designed for depths exceeding 5000 m has been developed to enhance the scientific understanding of deep oil and gas reservoirs.This temperature-preserved core chamber employs an innovative vacuum layer for temperature preservation and is compatible with a temperature-pressure preserved coring system.The design principles and key parameters of the temperature-preserved core chamber were determined through static analysis.Numerical simulations assessed the mechanical properties of 70,85,and 100 MPa core chambers under conditions of 120-150℃.The results demonstrate that the temperature-preserved core chambers withstand the applied stresses without plastic deformation,and the vacuum layer maintains its integrity under these conditions.A 70 MPa class core chamber prototype was manufactured,and system integration tests were performed on a self-developed in-situ coring platform.The system demonstrated stable operation at 70 MPa for 120 min,with pressure fluctuations within 5%.Additionally,the integrated system operated without interference,enabling the successful extraction of cores with a 50 mm diameter.These findings provide valuable theoretical guidance and design recommendations for advancing oil and gas in-situ temperature-pressure preserved coring technologies in high-temperature and high-pressure environments.展开更多
Gypsum caprocks'sealing ability is affected by temperature-pressure coupling.Due to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consid...Gypsum caprocks'sealing ability is affected by temperature-pressure coupling.Due to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure coupling.Triaxial stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility analysis.According to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more ductile.This reduces the amount of time it takes for the rock to transition from brittle to plastic.When temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal pressurization.The sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are compared.This provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved.展开更多
A novel wireless and passive surface acoustic wave(SAW)sensor is developed for measuring temperature and pressure.The sensor has two single-port resonators on a substrate.One resonator,acting as the temperature sensor...A novel wireless and passive surface acoustic wave(SAW)sensor is developed for measuring temperature and pressure.The sensor has two single-port resonators on a substrate.One resonator,acting as the temperature sensor,is located at the fixed end without pressure deformation,and the other one,acting as the pressure sensor,is located at the free end to detect pressure changes due to substrate deformation.Pressure at the free end bends the cantilever,causing a relative change in the acoustic propagation characteristics of the SAW traveling along the surface of the substrate and a relative change in the resonant frequency of the resulting signal.The temperature acts on the entire substrate,affecting the propagation speed of the SAW on the substrate and directly affecting the resonant frequency characteristic parameters.The temperature and pressure performance of this new antenna-connected sensor is tested by using a network analyzer,a constant temperature heating station,and a force gauge.A temperature sensitivity of 1.5015 kHz/℃and a pressure sensitivity of 10.6 kHz/gf at the ambient temperature have been observed by wireless measurements.This work should result in practical engineering applications for high-temperature devices.展开更多
By analyzing and studying a lot of weather charts and the weather condition of several typical cases,some kinds of unconventional high-altitude and ground weather situations whether the ground cold,warm front had the ...By analyzing and studying a lot of weather charts and the weather condition of several typical cases,some kinds of unconventional high-altitude and ground weather situations whether the ground cold,warm front had the precipitation in Jilin area were summarized.The results showed that the temperature field was the main element field which affected the weather variation.The analysis and research on the movement condition of cold,warm air in the different temperature-pressure field configuration in the high-altitude was the key of frontal precipitation weather forecast.展开更多
Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cor...Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cores and cannot guide the development of deep oil and gas resources on Earth. The fundamental reason is the lack of temperature and pressure control in in-situ coring environments. In this paper, a pressure control method of a coring device is studied. The theory and method of deep intelligent temperature-pressure coupling control are innovatively proposed, and a multifield coupling dynamic sealing model is established. The optimal cardinality three term PID (Proportional-Integral-Differential) intelligent control algorithm of pressure system is developed. The temperature-pressure characteristic of the gas-liquid two-phase cavity is analyzed, and the pressure intelligent control is carried out based on three term PID control algorithms. An in-situ condition-preserved coring (ICP-Coring) device is developed, and an intelligent control system for the temperature and pressure of the coring device is designed and verified by experiments. The results show that the temperature-pressure coupling control system can effectively realize stable sealing under temperature-pressure fields of 140 MPa and 150 °C. The temperature-pressure coupling control method can accurately realize a constant pressure inside the coring device. The maximum working pressure is 140 MPa, and the effective pressure compensation range is 20 MPa. The numerical simulation experiment of pressure system control algorithm is carried out, and the optimal cardinality and three term coefficients are obtained. The pressure steady-state error is less than 0.01%. The method of temperature-pressure coupling control has guiding significance for coring device research, and is also the basis for temperature-pressure decoupling control in ICP-Coring.展开更多
The Jingdezhen ductile shear zone is evolved from the Neoproterozoic Zhangyuan ophiolite melange belt in the eastern Jiangnan Orogen, South China. Comprehensive study of geometry, kinematics, quartz c-axis fabric, tem...The Jingdezhen ductile shear zone is evolved from the Neoproterozoic Zhangyuan ophiolite melange belt in the eastern Jiangnan Orogen, South China. Comprehensive study of geometry, kinematics, quartz c-axis fabric, temperature-pressure conditions and geochronology were conducted in this study. The Jingdezhen shear zone extends -180 km along the NE orientation with two groups of subvertical fo- liation and subhorizontal lineation. One group of foliation strikes NEN orientation whereas another one NEE orientation. Field investigation, microscopic observation and quartz c-axis fabric show that sinistral shearing along NEN-striking foliation occurred earlier than dextral shearing along NEE-striking foliation. Syn-tectonic staurolite porphyroblasts and deformation manner of feldspar imply that sinistral shearing occurred at 530-420 ℃ and 6-2 kbar. Deformation manner and c-axis fabric of quartz and pre-tectonic staurolite porphyroblasts indicate that dextral shearing took place at 420-300 ℃. LA-ICP-MS zircon U-Pb and mica ^40Ar/^39Ar dating indicate that the sinistral shearing occurred during Neoproterozoic oro- geny (830-800 Ma) whereas the dextral shearing at 447+12 Ma. The sinistral shearing resulted from the Neoproterozoic final assembly between the Yangtze and Cathaysia blocks. The dextral shearing was caused by Early Paleozoic orogen parallel extension and clockwise rotation.展开更多
We will build a cubic anvil cell (CAC) apparatus for high-pressure and low-temperature physical property measurements in the synergic extreme condition user facility (SECUF). In this article, we first introduce th...We will build a cubic anvil cell (CAC) apparatus for high-pressure and low-temperature physical property measurements in the synergic extreme condition user facility (SECUF). In this article, we first introduce the operating principle, the development history, and the current status of the CAC apparatus, and subsequently describe the design plan and technical targets for the CAC in SECUF. We will demonstrate the unique advantages of CAC, i.e., excellent pressure homogeneity and large hydrostatic pressure capacity, by summarizing our recent research progresses using CAC. Finally, we conclude by providing some perspectives on the applications of CAC in the related research fields.展开更多
The transientflow testing of ultra-deepwater gas wells is greatly impacted by the low temperatures of seawater encountered over extended distances.This leads to a redistribution of temperature within the wellbore,whic...The transientflow testing of ultra-deepwater gas wells is greatly impacted by the low temperatures of seawater encountered over extended distances.This leads to a redistribution of temperature within the wellbore,which in turn influences theflow behavior.To accurately predict such a temperature distribution,in this study a comprehensive model of theflowing temperature and pressurefields is developed.This model is based on principles offluid mechanics,heat transfer,mass conservation,and energy conservation and relies on the Runge-Kutta method for accurate integration in time of the resulting equations.The analysis includes the examination of the influence of various factors,such as gasflow production rate,thermal diffusivity of the formation,and thermal diffusivity of seawater,on the temperature and pressure profiles of the wellbore.The keyfindings can be summarized as follows:1.Higher production rates during testing lead to increasedflowing temperatures and decreased pressures within the wellbore.However,in the presence of a seawater thermocline,a crossover inflowing temperature is observed.2.An increase in wellbore pressure is associated with larger pipe diameters.3.Greater thermal diffusivity of the formation results in more rapid heat transfer from the wellbore to the formation,which causes lowerflowing temperatures within the wellbore.4.In an isothermal layer,higher thermal diffusivity of seawater leads to increased wellboreflowing temperatures.Conversely,in thermocline and mixed layer segments,lower temperatures are noted.5.Production test data from a representative deep-water gas well in the South China Sea,used to calculate the bottom-seafloor-wellhead temperature and pressurefields across three operating modes,indicate that the average error in temperature prediction is 2.18%,while the average error in pressure prediction is 5.26%,thereby confirming the reliability of the theoretical model.展开更多
Aiming at deep roadway anchorage solids, laboratory similar model tests were used to reveal the mechanical properties of anchorage solids with different anchorage lengths under the coupling effect of temperature and p...Aiming at deep roadway anchorage solids, laboratory similar model tests were used to reveal the mechanical properties of anchorage solids with different anchorage lengths under the coupling effect of temperature and pressure, and SPSS statistical analysis software was used to conduct linear regression analysis of the ultimate anchorage force obtained from the tests. The results show that: through multiple linear regression analysis, the influence degree of temperature and pressure coupling on the ultimate anchorage force is arranged in order of anchoring length > surrounding rock strength > temperature > side pressure coefficient, and the linear regression equation of the model is obtained. Compared with the linear regression equation of simulation results, the model has a high explanatory ability.展开更多
The coupling effect of temperature and confining pressure on fracture toughness is a critical issue in deep shale gas development that cannot be overlooked.Field and laboratory studies have shown that this coupling ef...The coupling effect of temperature and confining pressure on fracture toughness is a critical issue in deep shale gas development that cannot be overlooked.Field and laboratory studies have shown that this coupling effect significantly alters shale fracture toughness,but the underlying mechanisms of it remain poorly understood.To investigate the mechanisms of the temperature-pressure coupling effect on the fracture toughness of transversely isotropic shale,this study develops a thermal-mechanical DEM(discrete element method)model that integrates a customized thermal algorithm and a shining-lamp algorithm.The model validity is verified by using experimental results from high-temperature SCB(semi-circular bend)tests.Additionally,a series of SCB tests under different temperatures and confining pressures are simulated based on this model.The loading curves,fracture toughness evolution,crack morphology,and microcrack statistics results obtained from simulations are analyzed to provide insights into the mechanisms of the temperature-pressure coupling effect.The simulation results indicate that the stimulation of thermal-induced microcracks on crack propagation may be the primary microscopic mechanism behind the thermal-induced weakening of shale fracture toughness.Meanwhile,confining pressure has an inhibitory influence on the thermal effect of shale fracture toughness.The activation of shear microcracks under the application of confining pressure is identified as the leading microscopic mechanism of confining pressure inhibition.The findings in this study enhance the understanding of the fracture property evolution of deep shale reservoirs and provide guidance for site selection,engineering design,and reservoir stability assessment in deep shale gas development.展开更多
Nanoimprint lithography(NIL) is widely used in the fabrication of nano-scale semiconductor devices for its advantages of high resolution,low cost,and high throughput.However,traditional hard stamp imprinting has som...Nanoimprint lithography(NIL) is widely used in the fabrication of nano-scale semiconductor devices for its advantages of high resolution,low cost,and high throughput.However,traditional hard stamp imprinting has some drawbacks such as short stamp lifetime,bad uniformity in big areas,and large particle influence.In this paper, a flexible intermediate polymer stamp(IPS) is proposed to solve the drawbacks mentioned above.Meanwhile, we use a method of temperature-pressure variation imprinting to improve the resist liquidity in the process of imprinting,and eventually we achieve high quality patterns.This method combined with IPS has been used to fabricate a high quality grating whose half pitch is 50 nm.展开更多
基金the financial support from the National Key R&D Program of China(No.2022YFB3706604)the National Natural Science Foundation of China(52304033)+2 种基金the National Natural Science Foundation of China(No.51827901)Sichuan Science and Technology Program(2023NSFSC0790)China Postdoctoral Science Foundation(No.2023M742446)。
文摘A novel temperature-preserved core chamber designed for depths exceeding 5000 m has been developed to enhance the scientific understanding of deep oil and gas reservoirs.This temperature-preserved core chamber employs an innovative vacuum layer for temperature preservation and is compatible with a temperature-pressure preserved coring system.The design principles and key parameters of the temperature-preserved core chamber were determined through static analysis.Numerical simulations assessed the mechanical properties of 70,85,and 100 MPa core chambers under conditions of 120-150℃.The results demonstrate that the temperature-preserved core chambers withstand the applied stresses without plastic deformation,and the vacuum layer maintains its integrity under these conditions.A 70 MPa class core chamber prototype was manufactured,and system integration tests were performed on a self-developed in-situ coring platform.The system demonstrated stable operation at 70 MPa for 120 min,with pressure fluctuations within 5%.Additionally,the integrated system operated without interference,enabling the successful extraction of cores with a 50 mm diameter.These findings provide valuable theoretical guidance and design recommendations for advancing oil and gas in-situ temperature-pressure preserved coring technologies in high-temperature and high-pressure environments.
基金funded by the National Natural Science Foundation of China(Grant No.42172147)PetroChina Major Science and Technology Project(Grant No.ZD2019-183-002).
文摘Gypsum caprocks'sealing ability is affected by temperature-pressure coupling.Due to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure coupling.Triaxial stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility analysis.According to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more ductile.This reduces the amount of time it takes for the rock to transition from brittle to plastic.When temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal pressurization.The sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are compared.This provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved.
文摘A novel wireless and passive surface acoustic wave(SAW)sensor is developed for measuring temperature and pressure.The sensor has two single-port resonators on a substrate.One resonator,acting as the temperature sensor,is located at the fixed end without pressure deformation,and the other one,acting as the pressure sensor,is located at the free end to detect pressure changes due to substrate deformation.Pressure at the free end bends the cantilever,causing a relative change in the acoustic propagation characteristics of the SAW traveling along the surface of the substrate and a relative change in the resonant frequency of the resulting signal.The temperature acts on the entire substrate,affecting the propagation speed of the SAW on the substrate and directly affecting the resonant frequency characteristic parameters.The temperature and pressure performance of this new antenna-connected sensor is tested by using a network analyzer,a constant temperature heating station,and a force gauge.A temperature sensitivity of 1.5015 kHz/℃and a pressure sensitivity of 10.6 kHz/gf at the ambient temperature have been observed by wireless measurements.This work should result in practical engineering applications for high-temperature devices.
基金Supported by The Special Project of Public Welfare Industry Science and Research(GYHY200806014)The Project of Nanjing University of Information Science&Technology(E30JG0730)
文摘By analyzing and studying a lot of weather charts and the weather condition of several typical cases,some kinds of unconventional high-altitude and ground weather situations whether the ground cold,warm front had the precipitation in Jilin area were summarized.The results showed that the temperature field was the main element field which affected the weather variation.The analysis and research on the movement condition of cold,warm air in the different temperature-pressure field configuration in the high-altitude was the key of frontal precipitation weather forecast.
基金supported by the National Natural Science Foundation of China(grant numbers 51827901,51805340)funded by the Program for Guangdong Introducing Innovative and Enterpreneurial Teams(No.2019ZT08G315)Shenzhen Basic Research Program(General Program)(No.JCYJ20190808153416970).
文摘Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cores and cannot guide the development of deep oil and gas resources on Earth. The fundamental reason is the lack of temperature and pressure control in in-situ coring environments. In this paper, a pressure control method of a coring device is studied. The theory and method of deep intelligent temperature-pressure coupling control are innovatively proposed, and a multifield coupling dynamic sealing model is established. The optimal cardinality three term PID (Proportional-Integral-Differential) intelligent control algorithm of pressure system is developed. The temperature-pressure characteristic of the gas-liquid two-phase cavity is analyzed, and the pressure intelligent control is carried out based on three term PID control algorithms. An in-situ condition-preserved coring (ICP-Coring) device is developed, and an intelligent control system for the temperature and pressure of the coring device is designed and verified by experiments. The results show that the temperature-pressure coupling control system can effectively realize stable sealing under temperature-pressure fields of 140 MPa and 150 °C. The temperature-pressure coupling control method can accurately realize a constant pressure inside the coring device. The maximum working pressure is 140 MPa, and the effective pressure compensation range is 20 MPa. The numerical simulation experiment of pressure system control algorithm is carried out, and the optimal cardinality and three term coefficients are obtained. The pressure steady-state error is less than 0.01%. The method of temperature-pressure coupling control has guiding significance for coring device research, and is also the basis for temperature-pressure decoupling control in ICP-Coring.
基金supported by the National Natural Science Foundation of China (Nos. 41402174, 41472166)the Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)+1 种基金China Scholarship Council (No. 201406415007)the Natural Sciences and Engineering Research Council of Canada
文摘The Jingdezhen ductile shear zone is evolved from the Neoproterozoic Zhangyuan ophiolite melange belt in the eastern Jiangnan Orogen, South China. Comprehensive study of geometry, kinematics, quartz c-axis fabric, temperature-pressure conditions and geochronology were conducted in this study. The Jingdezhen shear zone extends -180 km along the NE orientation with two groups of subvertical fo- liation and subhorizontal lineation. One group of foliation strikes NEN orientation whereas another one NEE orientation. Field investigation, microscopic observation and quartz c-axis fabric show that sinistral shearing along NEN-striking foliation occurred earlier than dextral shearing along NEE-striking foliation. Syn-tectonic staurolite porphyroblasts and deformation manner of feldspar imply that sinistral shearing occurred at 530-420 ℃ and 6-2 kbar. Deformation manner and c-axis fabric of quartz and pre-tectonic staurolite porphyroblasts indicate that dextral shearing took place at 420-300 ℃. LA-ICP-MS zircon U-Pb and mica ^40Ar/^39Ar dating indicate that the sinistral shearing occurred during Neoproterozoic oro- geny (830-800 Ma) whereas the dextral shearing at 447+12 Ma. The sinistral shearing resulted from the Neoproterozoic final assembly between the Yangtze and Cathaysia blocks. The dextral shearing was caused by Early Paleozoic orogen parallel extension and clockwise rotation.
基金Project supported by the National Natural Science Foundation of China(Grant No.11574377)the State Key Development Program for Basic Research of China(Grant Nos.2018YFA0305700 and 2014CB921500)+1 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(Grant No.QYZDB-SSW-SLH013)the JSPS KAKENHI(Grant No.15H03681)
文摘We will build a cubic anvil cell (CAC) apparatus for high-pressure and low-temperature physical property measurements in the synergic extreme condition user facility (SECUF). In this article, we first introduce the operating principle, the development history, and the current status of the CAC apparatus, and subsequently describe the design plan and technical targets for the CAC in SECUF. We will demonstrate the unique advantages of CAC, i.e., excellent pressure homogeneity and large hydrostatic pressure capacity, by summarizing our recent research progresses using CAC. Finally, we conclude by providing some perspectives on the applications of CAC in the related research fields.
文摘The transientflow testing of ultra-deepwater gas wells is greatly impacted by the low temperatures of seawater encountered over extended distances.This leads to a redistribution of temperature within the wellbore,which in turn influences theflow behavior.To accurately predict such a temperature distribution,in this study a comprehensive model of theflowing temperature and pressurefields is developed.This model is based on principles offluid mechanics,heat transfer,mass conservation,and energy conservation and relies on the Runge-Kutta method for accurate integration in time of the resulting equations.The analysis includes the examination of the influence of various factors,such as gasflow production rate,thermal diffusivity of the formation,and thermal diffusivity of seawater,on the temperature and pressure profiles of the wellbore.The keyfindings can be summarized as follows:1.Higher production rates during testing lead to increasedflowing temperatures and decreased pressures within the wellbore.However,in the presence of a seawater thermocline,a crossover inflowing temperature is observed.2.An increase in wellbore pressure is associated with larger pipe diameters.3.Greater thermal diffusivity of the formation results in more rapid heat transfer from the wellbore to the formation,which causes lowerflowing temperatures within the wellbore.4.In an isothermal layer,higher thermal diffusivity of seawater leads to increased wellboreflowing temperatures.Conversely,in thermocline and mixed layer segments,lower temperatures are noted.5.Production test data from a representative deep-water gas well in the South China Sea,used to calculate the bottom-seafloor-wellhead temperature and pressurefields across three operating modes,indicate that the average error in temperature prediction is 2.18%,while the average error in pressure prediction is 5.26%,thereby confirming the reliability of the theoretical model.
文摘Aiming at deep roadway anchorage solids, laboratory similar model tests were used to reveal the mechanical properties of anchorage solids with different anchorage lengths under the coupling effect of temperature and pressure, and SPSS statistical analysis software was used to conduct linear regression analysis of the ultimate anchorage force obtained from the tests. The results show that: through multiple linear regression analysis, the influence degree of temperature and pressure coupling on the ultimate anchorage force is arranged in order of anchoring length > surrounding rock strength > temperature > side pressure coefficient, and the linear regression equation of the model is obtained. Compared with the linear regression equation of simulation results, the model has a high explanatory ability.
基金supported by the National Natural Science Foundation of China(No.42320104003).
文摘The coupling effect of temperature and confining pressure on fracture toughness is a critical issue in deep shale gas development that cannot be overlooked.Field and laboratory studies have shown that this coupling effect significantly alters shale fracture toughness,but the underlying mechanisms of it remain poorly understood.To investigate the mechanisms of the temperature-pressure coupling effect on the fracture toughness of transversely isotropic shale,this study develops a thermal-mechanical DEM(discrete element method)model that integrates a customized thermal algorithm and a shining-lamp algorithm.The model validity is verified by using experimental results from high-temperature SCB(semi-circular bend)tests.Additionally,a series of SCB tests under different temperatures and confining pressures are simulated based on this model.The loading curves,fracture toughness evolution,crack morphology,and microcrack statistics results obtained from simulations are analyzed to provide insights into the mechanisms of the temperature-pressure coupling effect.The simulation results indicate that the stimulation of thermal-induced microcracks on crack propagation may be the primary microscopic mechanism behind the thermal-induced weakening of shale fracture toughness.Meanwhile,confining pressure has an inhibitory influence on the thermal effect of shale fracture toughness.The activation of shear microcracks under the application of confining pressure is identified as the leading microscopic mechanism of confining pressure inhibition.The findings in this study enhance the understanding of the fracture property evolution of deep shale reservoirs and provide guidance for site selection,engineering design,and reservoir stability assessment in deep shale gas development.
文摘Nanoimprint lithography(NIL) is widely used in the fabrication of nano-scale semiconductor devices for its advantages of high resolution,low cost,and high throughput.However,traditional hard stamp imprinting has some drawbacks such as short stamp lifetime,bad uniformity in big areas,and large particle influence.In this paper, a flexible intermediate polymer stamp(IPS) is proposed to solve the drawbacks mentioned above.Meanwhile, we use a method of temperature-pressure variation imprinting to improve the resist liquidity in the process of imprinting,and eventually we achieve high quality patterns.This method combined with IPS has been used to fabricate a high quality grating whose half pitch is 50 nm.