CO_(2) drilling is a promising underbalance drilling technology with great advantages,such as lower cutting force,intense cooling and excellent lubrication.However,in the underbalance drilling,the mechanism of the cou...CO_(2) drilling is a promising underbalance drilling technology with great advantages,such as lower cutting force,intense cooling and excellent lubrication.However,in the underbalance drilling,the mechanism of the coupling CO_(2) jet and polycrystalline-diamond-compact(PDC)cutter are still unclear.Whereby,we established a coupled smoothed particle hydrodynamics/finite element method(SPH/FEM)model to simulate the composite rock-breaking of high-pressure CO_(2) jet&PDC cutter.Combined with the experimental research results,the mechanism of composite rock-breaking is studied from the perspectives of rock stress field,cutting force and jet field.The results show that the composite rock-breaking can effectively relieve the influence of vibration and shock on PDC cutter.Meanwhile,the high-pressure CO_(2) jet has a positive effect on carrying rock debris,which can effectively reduce the temperature rising and the thermal wear of the PDC cutter.In addition,the effects of CO_(2) jet parameters on composite rock-breaking were studied,such as jet impact velocity,nozzle diameter,jet injection angle and impact distance.The studies show that when the impact velocity of the CO_(2) jet is greater than 250 m/s,the CO_(2) jet could quickly break the rock.It is found that the optimal range of nozzle diameter is 1.5–2.5 mm,the best injection angle of CO_(2) jet is 60,the optimal impact distance is 10 times the nozzle diameter.The above studies could provide theoretical supports and technical guidance for composite rock-breaking,which is useful for the CO_(2) underbalance drilling and drill bit design.展开更多
A simulate daily oriental dietary pattern(a blend of lard and soybean oil)was performed in this research to investigate influence on liver and kidney function.Sixty mice were randomly divided into 6 groups with diets ...A simulate daily oriental dietary pattern(a blend of lard and soybean oil)was performed in this research to investigate influence on liver and kidney function.Sixty mice were randomly divided into 6 groups with diets of different fat added oils respectively for 12 weeks.Malondialdehyde and uric acid contents in mice fed with blended oil were significantly lower than in those fed only with soybean oil and lard due to the improved activities of antioxidant enzymes.Daily use of a blend of lard with soybean oil significantly increased antioxidant capacity,reduced lipid peroxidation of liver and serum uric acid production,thus protected liver and renal function.It also suggests that the oriental dietary pattern might reduce the risk of gout.展开更多
Endometriosis refers to as an estrogen-dependent disease.Estrogen receptorβ(ERB),the main estrogen receptor subtype which is encoded by the estrogen receptor 2(ESR2)gene,can mediate the action of estrogen in endometr...Endometriosis refers to as an estrogen-dependent disease.Estrogen receptorβ(ERB),the main estrogen receptor subtype which is encoded by the estrogen receptor 2(ESR2)gene,can mediate the action of estrogen in endometriosis.Although selective estrogen receptor modulators can target the ERβ,they are not specific due to the wide distribution of ERβ.Recently,long noncoding RNAs have been implicated in endometriosis.Therefore,we aim to explore and validate the downstream regulatory mechanism of ERβ,and to investigate the potential role of long intergenic noncoding RNA 1018(LINC01018)as a nonhormonal treatment for endometriosis.Our study demonstrates that the expression levels of ESR2 and LINCo1018 are increased in ectopic endometrial tissues and reveals a significant positive correlation between the ESR2 and LINCo1018 expression.Mechanistically,ERβdirectly binds to an estrogen response element located in the LINCO1018 promoter region and activates LINC01018 transcription.Functionally,ERβcan regulate the CDC25C/CDK1/CyclinB1 pathway and promote ectopic endometrial stromal cell proliferation via LINC01018 in vitro.Consistent with these findings,the knockdown of LINC01018 inhibits endometriotic lesion proliferation in vivo.In summary,our study demonstrates that the ERβ/LINC01018/CDC25C/CDK1/CyclinB1 signaling axis regulates endometriosis progression.展开更多
Although several theoretical calculation methods for high-pressure jet are available,there is currently no theoretical model for the high-pressure CO_(2)jet based on the high-precision equation of state(EOS).To invest...Although several theoretical calculation methods for high-pressure jet are available,there is currently no theoretical model for the high-pressure CO_(2)jet based on the high-precision equation of state(EOS).To investigate the flow field of the high-pressure CO_(2)jet in cases of the composite rock-breaking under the high-pressure CO_(2)Jet and PDC cutter,a semi-analytical approach of the high-pressure CO_(2)jet is developed based on the Span-Wagner EOS and CO_(2)jet theory.The semi-analytical calculations and the physical property calculations under the action of the high-pressure CO_(2)jet are conducted with consideration of the jet pressure,the jet distance,the nozzle diameter and the jet angle.The results indicate that the distribution of the physical properties calculated by the semi-analytical approaches is similar to that obtained by experimental monitoring and numerical simulation,which indicates that the calculation method of the high-pressure CO_(2)jet presented in this paper is effective and reliable.The properties of the CO_(2)jet obtained by the theoretical calculation see a significant difference between the initial region and the jet impact region.At the temperature of 300 K,the increase of the initial pressure can effectively increase the impact force and the cooling ability of the jet.The proportion of the jet core lengths in the jet on the axis increases with the increase of the ratio of the nozzle diameter to the jet length,accompanied with the increase of the impact force of the jet.The increase of the jet angle can effectively increase the impacting force of the jet,but hampers the fluid diffusion.The study combines the theoretical calculation of the jet with the calculation of the physical properties of the high-pressure CO_(2),for comprehensively understanding the CO_(2)jet field in the composite rock-breaking under the action of the high-pressure CO_(2)jet and PDC cutter.This theoretical calculation of the CO_(2)jet based on the high-precision EOS provides an option for the convenient calculation of the CO_(2)drilling in practical engineering.展开更多
The acoustic response of gas and/or water saturated coal rock is fundamental for establishing the correspondence between the physical properties of the coal reservoir and the characteristics of the well-logging respon...The acoustic response of gas and/or water saturated coal rock is fundamental for establishing the correspondence between the physical properties of the coal reservoir and the characteristics of the well-logging response,which is the technology essential for the geophysical exploration of coalbed methane(CBM).This acoustic response depends on water(Sw)and gas(Sg)saturation among other factors.In this study,we performed acoustic tests on dry and different gas-water saturated coal samples with different degrees of metamorphism and deformation,collected from several coal mining areas in China.These tests enabled us to analyze the influence of coal type and gas-water saturation on the acoustic response of CBM formations.Our results show that the acoustic velocity of P-wave and S-wave(Vp and Vs,respectively),and the relative anisotropy of and Vs,increased with increasing vitrinite reflectance,density,Vp and Sw.WithSw increasing from 0 to 100%,the growth rate of the acoustic velocity decreased with increasing vitrinite reflectance.The Vp/Vs ratio of tectonic coal was generally higher than that of primary coal.The growth rate of the relative anisotropy in tectonic coal was markedly higher than that in primary coal.展开更多
Gas diffusion in the coal matrix plays a significant role in forecasting the production performance of coalbed methane(CBM)wells.To better understand methane diffusion behavior,a systematic study was performed on vari...Gas diffusion in the coal matrix plays a significant role in forecasting the production performance of coalbed methane(CBM)wells.To better understand methane diffusion behavior,a systematic study was performed on various rank coals with vitrinite reflectance(Ro,m)ranging from 0.46%to 2.79%.Multiple experiments,including coal petrographic analysis,field emission scanning electron microscopy(FESEM),low-temperature N2 adsorption/desorption,and mercury intrusion porosimetry(MIP),were conducted to quantitatively characterize the multiscale micro-nano pore system in different rank coals,which showed that the pore structure of coals exhibited a multimodal pore size and volume distribution.Isothermal adsorption-diffusion experiments using the volumetric method were also performed to understand the methane diffusion characteristics in the micro-nano pores of the coal reservoir.The applicability of the multiporous diffusion model is verified,and methane diffusion in the multi-scale pores of coal reservoirs exhibits the characteristics of early fast diffusion,transitional diffusion in the medium term,and slow diffusion in the later period.In addition,the factors affecting methane diffusion in coals were systematically analyzed,and gray relational analysis(GRA)was employed to analyze and identify the importance of these factors on methane diffusion.The results show the impact ranking of factors,in order from the most important to the least:particle size>moisture>surface area>pore volume>pressure>coal rank>temperature in all of three diffusion stages.These findings are helpful for forecasting production performance and enhancing the production efficiency of CBM.展开更多
基金This work was supported by the National Natural Science Foundation of China(No.52004236)Sichuan Science and Technology Program(No.2021JDRC0114)+4 种基金the Starting Project of Southwest Petroleum University(No.2019QHZ009)the China Postdoctoral Science Foundation(No.2020M673285)the Open Project Program of Key Laboratory of Groundwater Resources and Environment(Jilin University)Ministry of Education(No.202005009KF)the Chinese Scholarship Council(CSC)funding(No.202008515107).
文摘CO_(2) drilling is a promising underbalance drilling technology with great advantages,such as lower cutting force,intense cooling and excellent lubrication.However,in the underbalance drilling,the mechanism of the coupling CO_(2) jet and polycrystalline-diamond-compact(PDC)cutter are still unclear.Whereby,we established a coupled smoothed particle hydrodynamics/finite element method(SPH/FEM)model to simulate the composite rock-breaking of high-pressure CO_(2) jet&PDC cutter.Combined with the experimental research results,the mechanism of composite rock-breaking is studied from the perspectives of rock stress field,cutting force and jet field.The results show that the composite rock-breaking can effectively relieve the influence of vibration and shock on PDC cutter.Meanwhile,the high-pressure CO_(2) jet has a positive effect on carrying rock debris,which can effectively reduce the temperature rising and the thermal wear of the PDC cutter.In addition,the effects of CO_(2) jet parameters on composite rock-breaking were studied,such as jet impact velocity,nozzle diameter,jet injection angle and impact distance.The studies show that when the impact velocity of the CO_(2) jet is greater than 250 m/s,the CO_(2) jet could quickly break the rock.It is found that the optimal range of nozzle diameter is 1.5–2.5 mm,the best injection angle of CO_(2) jet is 60,the optimal impact distance is 10 times the nozzle diameter.The above studies could provide theoretical supports and technical guidance for composite rock-breaking,which is useful for the CO_(2) underbalance drilling and drill bit design.
基金supported by the grants of Innovation and Entrepreneurship Investment Project in Hunan(2017GK5009)Postgraduate Scientific Research and Innovation Project of Hunan(CX20190500)+1 种基金the Hunan Collaborative Innovation Center of Animal Production Safety,Laboratory of Animal Clinical Toxicology at The Department of Veterinary,Hunan Agriculture UniversityAnimal Health Care Engineering Technology Research Center of Hunan Agricultural University。
文摘A simulate daily oriental dietary pattern(a blend of lard and soybean oil)was performed in this research to investigate influence on liver and kidney function.Sixty mice were randomly divided into 6 groups with diets of different fat added oils respectively for 12 weeks.Malondialdehyde and uric acid contents in mice fed with blended oil were significantly lower than in those fed only with soybean oil and lard due to the improved activities of antioxidant enzymes.Daily use of a blend of lard with soybean oil significantly increased antioxidant capacity,reduced lipid peroxidation of liver and serum uric acid production,thus protected liver and renal function.It also suggests that the oriental dietary pattern might reduce the risk of gout.
基金the National Natural Science Foundation of China(82271676)for funding support.
文摘Endometriosis refers to as an estrogen-dependent disease.Estrogen receptorβ(ERB),the main estrogen receptor subtype which is encoded by the estrogen receptor 2(ESR2)gene,can mediate the action of estrogen in endometriosis.Although selective estrogen receptor modulators can target the ERβ,they are not specific due to the wide distribution of ERβ.Recently,long noncoding RNAs have been implicated in endometriosis.Therefore,we aim to explore and validate the downstream regulatory mechanism of ERβ,and to investigate the potential role of long intergenic noncoding RNA 1018(LINC01018)as a nonhormonal treatment for endometriosis.Our study demonstrates that the expression levels of ESR2 and LINCo1018 are increased in ectopic endometrial tissues and reveals a significant positive correlation between the ESR2 and LINCo1018 expression.Mechanistically,ERβdirectly binds to an estrogen response element located in the LINCO1018 promoter region and activates LINC01018 transcription.Functionally,ERβcan regulate the CDC25C/CDK1/CyclinB1 pathway and promote ectopic endometrial stromal cell proliferation via LINC01018 in vitro.Consistent with these findings,the knockdown of LINC01018 inhibits endometriotic lesion proliferation in vivo.In summary,our study demonstrates that the ERβ/LINC01018/CDC25C/CDK1/CyclinB1 signaling axis regulates endometriosis progression.
基金This work was supported by the Sichuan Science and Technology Program(Grant No.2021JDRC0114)the Starting Project of Southwest Petroleum University(Grant No.2019QHZ009)+2 种基金the China Postdoctoral Science Foundation(Grant No.2020M673285)the Open Project Program of Key Laboratory of Groundwater Resources and Environment,Ministry of Education,Jilin University(Grant No.202005009KF)the Chinese Scholarship Council funding(Grant No.202008515107).
文摘Although several theoretical calculation methods for high-pressure jet are available,there is currently no theoretical model for the high-pressure CO_(2)jet based on the high-precision equation of state(EOS).To investigate the flow field of the high-pressure CO_(2)jet in cases of the composite rock-breaking under the high-pressure CO_(2)Jet and PDC cutter,a semi-analytical approach of the high-pressure CO_(2)jet is developed based on the Span-Wagner EOS and CO_(2)jet theory.The semi-analytical calculations and the physical property calculations under the action of the high-pressure CO_(2)jet are conducted with consideration of the jet pressure,the jet distance,the nozzle diameter and the jet angle.The results indicate that the distribution of the physical properties calculated by the semi-analytical approaches is similar to that obtained by experimental monitoring and numerical simulation,which indicates that the calculation method of the high-pressure CO_(2)jet presented in this paper is effective and reliable.The properties of the CO_(2)jet obtained by the theoretical calculation see a significant difference between the initial region and the jet impact region.At the temperature of 300 K,the increase of the initial pressure can effectively increase the impact force and the cooling ability of the jet.The proportion of the jet core lengths in the jet on the axis increases with the increase of the ratio of the nozzle diameter to the jet length,accompanied with the increase of the impact force of the jet.The increase of the jet angle can effectively increase the impacting force of the jet,but hampers the fluid diffusion.The study combines the theoretical calculation of the jet with the calculation of the physical properties of the high-pressure CO_(2),for comprehensively understanding the CO_(2)jet field in the composite rock-breaking under the action of the high-pressure CO_(2)jet and PDC cutter.This theoretical calculation of the CO_(2)jet based on the high-precision EOS provides an option for the convenient calculation of the CO_(2)drilling in practical engineering.
基金This research was funded by the National Natural Science Foundation of China(Grant Nos.42130806,41922016,41830427 and 41772160).
文摘The acoustic response of gas and/or water saturated coal rock is fundamental for establishing the correspondence between the physical properties of the coal reservoir and the characteristics of the well-logging response,which is the technology essential for the geophysical exploration of coalbed methane(CBM).This acoustic response depends on water(Sw)and gas(Sg)saturation among other factors.In this study,we performed acoustic tests on dry and different gas-water saturated coal samples with different degrees of metamorphism and deformation,collected from several coal mining areas in China.These tests enabled us to analyze the influence of coal type and gas-water saturation on the acoustic response of CBM formations.Our results show that the acoustic velocity of P-wave and S-wave(Vp and Vs,respectively),and the relative anisotropy of and Vs,increased with increasing vitrinite reflectance,density,Vp and Sw.WithSw increasing from 0 to 100%,the growth rate of the acoustic velocity decreased with increasing vitrinite reflectance.The Vp/Vs ratio of tectonic coal was generally higher than that of primary coal.The growth rate of the relative anisotropy in tectonic coal was markedly higher than that in primary coal.
基金This research was funded by the National Natural Science Foundation of China(Grant Nos.41922016,41830427,and 41772160)the Fundamental Research Funds for the Central Universities(No.2652019264).
文摘Gas diffusion in the coal matrix plays a significant role in forecasting the production performance of coalbed methane(CBM)wells.To better understand methane diffusion behavior,a systematic study was performed on various rank coals with vitrinite reflectance(Ro,m)ranging from 0.46%to 2.79%.Multiple experiments,including coal petrographic analysis,field emission scanning electron microscopy(FESEM),low-temperature N2 adsorption/desorption,and mercury intrusion porosimetry(MIP),were conducted to quantitatively characterize the multiscale micro-nano pore system in different rank coals,which showed that the pore structure of coals exhibited a multimodal pore size and volume distribution.Isothermal adsorption-diffusion experiments using the volumetric method were also performed to understand the methane diffusion characteristics in the micro-nano pores of the coal reservoir.The applicability of the multiporous diffusion model is verified,and methane diffusion in the multi-scale pores of coal reservoirs exhibits the characteristics of early fast diffusion,transitional diffusion in the medium term,and slow diffusion in the later period.In addition,the factors affecting methane diffusion in coals were systematically analyzed,and gray relational analysis(GRA)was employed to analyze and identify the importance of these factors on methane diffusion.The results show the impact ranking of factors,in order from the most important to the least:particle size>moisture>surface area>pore volume>pressure>coal rank>temperature in all of three diffusion stages.These findings are helpful for forecasting production performance and enhancing the production efficiency of CBM.
