Based on the coalbed methane(CBM)/coal-rock gas(CRG)geological,geophysical,and experimental testing data from the Daji block in the Ordos Basin,the coal-forming and hydrocarbon generation&accumulation characterist...Based on the coalbed methane(CBM)/coal-rock gas(CRG)geological,geophysical,and experimental testing data from the Daji block in the Ordos Basin,the coal-forming and hydrocarbon generation&accumulation characteristics across different zones were dissected,and the key factors controlling the differential CBM/CRG enrichment were identified.The No.8 coal seam of the Carboniferous Benxi Formation in the Daji block is 8-10 m thick,typically overlain by limestone.The primary hydrocarbon generation phase occurred during the Early Cretaceous.Based on the differences in tectonic evolution and CRG occurrence,and with the maximum vitrinite reflectance of 2.0%and burial depth of 1800 m as boundaries,the study area is divided into deeply buried and deeply preserved,deeply buried and shallowly preserved,and shallowly buried and shallowly preserved zones.The deeply buried and deeply preserved zone contains gas content of 22-35 m^(3)/t,adsorbed gas saturation of 95%-100%,and formation water with total dissolved solid(TDS)higher than 50000 mg/L.This zone features structural stability and strong sealing capacity,with high gas production rates.The deeply buried and shallowly preserved zone contains gas content of 16-20 m^(3)/t,adsorbed gas saturation of 80%-95%,and formation water with TDS of 5000-50000 mg/L.This zone exhibits localized structural modification and hydrodynamic sealing,with moderate gas production rate.The shallowly buried and shallowly preserved zone contains gas content of 8-16 m^(3)/t,adsorbed gas saturation of 50%-70%,and formation water with TDS lower than 5000 mg/L.This zone experienced intense uplift,resulting in poor sealing and secondary alteration of the primary gas reservoir,with partial adsorbed gas loss,and low gas production rate.A depositional unification and structural divergence model is proposed,that is,although coal seams across the basin experienced broadly similar depositional and tectonic histories,differences in tectonic intensity have led to spatial heterogeneity in the maximum burial depth(i.e.,thermal maturity of coal)and current burial depth and occurrence of CRG(i.e.,gas content and occurrence state).The research results provide valuable guidance for advancing the theoretical understanding of CBM/CRG enrichment and for improving exploration and development practices.展开更多
[Objective] The aim was to analyze yield stability of attar No.8, which is direct sowing and early-maturing. [Method] Analysis was made on yielding ability, stability and adaptability of attar No.8 in Yunnan Province ...[Objective] The aim was to analyze yield stability of attar No.8, which is direct sowing and early-maturing. [Method] Analysis was made on yielding ability, stability and adaptability of attar No.8 in Yunnan Province during 2006-2009 with DPS software and stability assessment was conducted on yield and major economic characters of the variety in different periods and experimental plots. [Result] Average yield of attar No.8 during three years in 24 plots achieved 3 379.17 kg/hm2; it grew tightly and is featured with early matureness. In addition, grain density, pod number and annul production differed little in different years and the variety in eight ecological conditions all showed high production potential, yielding ability and stability, which proved that attar No.8 is suitable to be grown in Yunnan and southern early-maturing areas in China. [Conclusion] The research provided references for selection and breeding of rapeseeds' variety which enjoys high and stable yield.展开更多
Weighted Estimates for Multilinear Pseudodifferential Operators Kang Wei LI;Wen Chang SUN Abstract In this paper,we study the weighted estimates for multilinear pseudodifferential operators.We show that a multilinear ...Weighted Estimates for Multilinear Pseudodifferential Operators Kang Wei LI;Wen Chang SUN Abstract In this paper,we study the weighted estimates for multilinear pseudodifferential operators.We show that a multilinear pseudodifferential operator is bounded with respect to multiple weights whenever its symbol satisfies some smoothness and decay conditions.Our result generalizes similar ones from the classical A_p weights to multiple weights.Trigonometric Series With a Generalized Monotonicity展开更多
A New Functor from D_5-Mod to E_6-Mod Xiao Ping XU Abstract We find a new representation of the simple Lie algebra of type E_6 on the polynomial algebra in 16 variables,which gives a fractional representation of the c...A New Functor from D_5-Mod to E_6-Mod Xiao Ping XU Abstract We find a new representation of the simple Lie algebra of type E_6 on the polynomial algebra in 16 variables,which gives a fractional representation of the corresponding Lie group on 16-dimensional space.Using this representation and Shen's idea of mixed product,we construct a new functor from D_5-Mod to E_6-Mod.A condition for the functor to map展开更多
Two field surveys on the thickness of Hei Valley No. 8 Glacier (H8) on the southern slope of Mount Bogda in the Tianshan Mountains using ground-penetration radar (GPR) were carried out in August 2008 and Septembe...Two field surveys on the thickness of Hei Valley No. 8 Glacier (H8) on the southern slope of Mount Bogda in the Tianshan Mountains using ground-penetration radar (GPR) were carried out in August 2008 and September 2009. Comparisons of the observed change in glacier thickness using GPR and ablation stakes suggest that GPR observations have high accuracy. Thus, the thickness change for H8 during 2008-2009 was estimated using GPR data. Digital elevation models obtained from topographic maps and the Shuttle Radar Topography Mission were used to analyze ice-elevation changes of H8 between 1 969 and 2 000 m a.s.l.. The results show that H8 has continually thinned, and the thinning rate has increased gradually. The thinning of ablation areas of H8 increased from 0.42a=0.56 m/a in 1969-2000 to 1.474-0.79 m/a in 2000-2008, and then accelerated to 1.924-0.98 m/a in 2008-2009. The retreat of the glacier terminus has had a similar pattern. The distribution of the temperate-ice zone of H8 as determined from GPR data also implies that H8 has experienced strong melting from 2008 to 2009, which indicates that temperature rises have not only enhanced glacial sur- face melting and prolonged melting periods, but also changed the englacial structure and increased the water content of glacier, both of which probably lead to the acceleration of glacial thinning.展开更多
The study aimed to examine the applicability of carbon nanoparticles as a tracer for lymph node mapping and the related factors of lymph node and No.8p subgroup metastasis in patients with gastric cancer.Clinical data...The study aimed to examine the applicability of carbon nanoparticles as a tracer for lymph node mapping and the related factors of lymph node and No.8p subgroup metastasis in patients with gastric cancer.Clinical data of 50 patients with gastric cancer,who had not received treatment preoperatively and underwent gastrectomy in Department of Gastrointestinal Surgery,Wuhan Union Hospital,between October 2014 and August 2015,were retrospectively analyzed.These patients were found to have no distant metastasis preoperatively.Thirty-five out of 50 patients were subjected to lymphatic mapping technique using carbon nanoparticles as the tracer,and the rest 15 cases did not experience the lymphatic mapping and served as controls.The sensitivity,specificity,false positive rate and false negative rate were calculated according to the number of lymph nodes,and the staining and metastasis condition of lymph nodes.The diagnostic value of carbon nanoparticles on metastatic lymph nodes was evaluated.The relationship between the metastasis of lymph nodes or subgroup No.8p lymph nodes and clinicopathologic features was analyzed by χ^2-test or Fisher's exact test.All patients underwent D2 surgery(lymph node dissection including all the group 1 and group 2 nodes) plus the dissection of the subgroup No.8p lymph nodes.It was found that the average number of harvested lymph nodes in lymphatic mapping technique group(45.7±14.5) was greater than that in control group(39.2±11.7),but the difference was not significantly different(P=0.138〉0.05).The success rate,the accuracy,sensitivity,specificity and false negative rate was 97%,57%,28%,62% and 72% respectively.The metastasis of lymph nodes was correlated to the depth of cancer invasion(T stage)(P=0.004〈0.05),and the metastasis of No.8p lymph nodes was correlated to the extent of lymph node involvement(N stage)(P=0.007〈0.05).Six cases had lymph node metastasis in subgroup No.8p,and their TNM stages and clinical stages were as follows:T1N2M0 ⅡA,T3N3M0 ⅢB,T4 a N3M0 ⅢC,T4 a N3M0 ⅢC,T4 a N3M0 ⅢC,and T4 b N3M0 ⅢC.In conclusion,our study indicated that carbon nanoparticles failed to show good selectivity for metastatic lymph nodes;the result of lymphatic mapping does not achieve a satisfactory performance;the incidence of lymph node metastasis may increase,accompanying with the increase of the depth of cancer invasion;No.8p lymph node metastasis tends to occur for gastric carcinoma patients with the extent of lymph node metastasis over N2 stage.展开更多
Deep coal reservoirs(buried depth>2000 m)represent a significant yet underexploited resource for coalbed methane(CBM)production.In these reservoirs,CBM primarily exists in adsorbed and free phase,with the pore stru...Deep coal reservoirs(buried depth>2000 m)represent a significant yet underexploited resource for coalbed methane(CBM)production.In these reservoirs,CBM primarily exists in adsorbed and free phase,with the pore structure playing a critical role in gas storage and migration.The Jiaxian block in the northeastern Ordos Basin,has emerged as a key area for deep CBM exploration due to its promising resource potential.However,the pore structure characteristics of the No.8 coal seam in Jiaxian block and their implications for gas storage and production remain poorly understood.A comprehensive characterization of the No.8 coal seam's pore structure is conducted in the study using multiple methods including high-pressure mercury injection,N2/CO_(2)adsorption experiments,and integration of measured core gas content data and production history.The study results reveal that the pores can be mainly classified as vesicles and cellular pores,and the fractures are mainly static pressure fractures.Micropores(pore diameter<10 nm)dominate the pore system(accounting for more than 99%of the total specific surface area),providing important adsorption sites for gas storage.Although mesopores(pore diameter of 100-1000 nm)and macropores(pore diameter>1000 nm)account for a small proportion,they feature effective storage spaces and interconnectivity,resulting in a high proportion of free gas.Therefore,the reservoirs shows great development potential after stimulation(such as hydraulic fracturing).These findings emphasize the feasibility of large-scale and long-term development of CBM in the Jiaxian block in terms of reservoir space,gas content and production characteristics.This study serves to lay a scientific basis for its efficient exploitation.展开更多
基金Supported by the China National Science and Technology Major Project(2025ZD1405700)CNPC Science and Technology Project(2023YQX20117).
文摘Based on the coalbed methane(CBM)/coal-rock gas(CRG)geological,geophysical,and experimental testing data from the Daji block in the Ordos Basin,the coal-forming and hydrocarbon generation&accumulation characteristics across different zones were dissected,and the key factors controlling the differential CBM/CRG enrichment were identified.The No.8 coal seam of the Carboniferous Benxi Formation in the Daji block is 8-10 m thick,typically overlain by limestone.The primary hydrocarbon generation phase occurred during the Early Cretaceous.Based on the differences in tectonic evolution and CRG occurrence,and with the maximum vitrinite reflectance of 2.0%and burial depth of 1800 m as boundaries,the study area is divided into deeply buried and deeply preserved,deeply buried and shallowly preserved,and shallowly buried and shallowly preserved zones.The deeply buried and deeply preserved zone contains gas content of 22-35 m^(3)/t,adsorbed gas saturation of 95%-100%,and formation water with total dissolved solid(TDS)higher than 50000 mg/L.This zone features structural stability and strong sealing capacity,with high gas production rates.The deeply buried and shallowly preserved zone contains gas content of 16-20 m^(3)/t,adsorbed gas saturation of 80%-95%,and formation water with TDS of 5000-50000 mg/L.This zone exhibits localized structural modification and hydrodynamic sealing,with moderate gas production rate.The shallowly buried and shallowly preserved zone contains gas content of 8-16 m^(3)/t,adsorbed gas saturation of 50%-70%,and formation water with TDS lower than 5000 mg/L.This zone experienced intense uplift,resulting in poor sealing and secondary alteration of the primary gas reservoir,with partial adsorbed gas loss,and low gas production rate.A depositional unification and structural divergence model is proposed,that is,although coal seams across the basin experienced broadly similar depositional and tectonic histories,differences in tectonic intensity have led to spatial heterogeneity in the maximum burial depth(i.e.,thermal maturity of coal)and current burial depth and occurrence of CRG(i.e.,gas content and occurrence state).The research results provide valuable guidance for advancing the theoretical understanding of CBM/CRG enrichment and for improving exploration and development practices.
基金Supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2010BAD01B08)Yunnan Programs for Science and Technology Development(2011BB010)+2 种基金Fund for Fostering Talents in Yunnan Province(2011CI062)National Program of Modern Industrial Technology System of Rapeseed(NYCYTX-00564)Program of Modern Industrial Technology System of Rapeseed in Yunnan Province~~
文摘[Objective] The aim was to analyze yield stability of attar No.8, which is direct sowing and early-maturing. [Method] Analysis was made on yielding ability, stability and adaptability of attar No.8 in Yunnan Province during 2006-2009 with DPS software and stability assessment was conducted on yield and major economic characters of the variety in different periods and experimental plots. [Result] Average yield of attar No.8 during three years in 24 plots achieved 3 379.17 kg/hm2; it grew tightly and is featured with early matureness. In addition, grain density, pod number and annul production differed little in different years and the variety in eight ecological conditions all showed high production potential, yielding ability and stability, which proved that attar No.8 is suitable to be grown in Yunnan and southern early-maturing areas in China. [Conclusion] The research provided references for selection and breeding of rapeseeds' variety which enjoys high and stable yield.
文摘Weighted Estimates for Multilinear Pseudodifferential Operators Kang Wei LI;Wen Chang SUN Abstract In this paper,we study the weighted estimates for multilinear pseudodifferential operators.We show that a multilinear pseudodifferential operator is bounded with respect to multiple weights whenever its symbol satisfies some smoothness and decay conditions.Our result generalizes similar ones from the classical A_p weights to multiple weights.Trigonometric Series With a Generalized Monotonicity
文摘A New Functor from D_5-Mod to E_6-Mod Xiao Ping XU Abstract We find a new representation of the simple Lie algebra of type E_6 on the polynomial algebra in 16 variables,which gives a fractional representation of the corresponding Lie group on 16-dimensional space.Using this representation and Shen's idea of mixed product,we construct a new functor from D_5-Mod to E_6-Mod.A condition for the functor to map
基金funded by the Project of the Knowledge Inno-vation of Chinese Academy of Sciences(No.KZCX2-YW-GJ04)Postdoctoral Projects of China(Nos.2012M 521817 and 2013M 5320 96)
文摘Two field surveys on the thickness of Hei Valley No. 8 Glacier (H8) on the southern slope of Mount Bogda in the Tianshan Mountains using ground-penetration radar (GPR) were carried out in August 2008 and September 2009. Comparisons of the observed change in glacier thickness using GPR and ablation stakes suggest that GPR observations have high accuracy. Thus, the thickness change for H8 during 2008-2009 was estimated using GPR data. Digital elevation models obtained from topographic maps and the Shuttle Radar Topography Mission were used to analyze ice-elevation changes of H8 between 1 969 and 2 000 m a.s.l.. The results show that H8 has continually thinned, and the thinning rate has increased gradually. The thinning of ablation areas of H8 increased from 0.42a=0.56 m/a in 1969-2000 to 1.474-0.79 m/a in 2000-2008, and then accelerated to 1.924-0.98 m/a in 2008-2009. The retreat of the glacier terminus has had a similar pattern. The distribution of the temperate-ice zone of H8 as determined from GPR data also implies that H8 has experienced strong melting from 2008 to 2009, which indicates that temperature rises have not only enhanced glacial sur- face melting and prolonged melting periods, but also changed the englacial structure and increased the water content of glacier, both of which probably lead to the acceleration of glacial thinning.
文摘The study aimed to examine the applicability of carbon nanoparticles as a tracer for lymph node mapping and the related factors of lymph node and No.8p subgroup metastasis in patients with gastric cancer.Clinical data of 50 patients with gastric cancer,who had not received treatment preoperatively and underwent gastrectomy in Department of Gastrointestinal Surgery,Wuhan Union Hospital,between October 2014 and August 2015,were retrospectively analyzed.These patients were found to have no distant metastasis preoperatively.Thirty-five out of 50 patients were subjected to lymphatic mapping technique using carbon nanoparticles as the tracer,and the rest 15 cases did not experience the lymphatic mapping and served as controls.The sensitivity,specificity,false positive rate and false negative rate were calculated according to the number of lymph nodes,and the staining and metastasis condition of lymph nodes.The diagnostic value of carbon nanoparticles on metastatic lymph nodes was evaluated.The relationship between the metastasis of lymph nodes or subgroup No.8p lymph nodes and clinicopathologic features was analyzed by χ^2-test or Fisher's exact test.All patients underwent D2 surgery(lymph node dissection including all the group 1 and group 2 nodes) plus the dissection of the subgroup No.8p lymph nodes.It was found that the average number of harvested lymph nodes in lymphatic mapping technique group(45.7±14.5) was greater than that in control group(39.2±11.7),but the difference was not significantly different(P=0.138〉0.05).The success rate,the accuracy,sensitivity,specificity and false negative rate was 97%,57%,28%,62% and 72% respectively.The metastasis of lymph nodes was correlated to the depth of cancer invasion(T stage)(P=0.004〈0.05),and the metastasis of No.8p lymph nodes was correlated to the extent of lymph node involvement(N stage)(P=0.007〈0.05).Six cases had lymph node metastasis in subgroup No.8p,and their TNM stages and clinical stages were as follows:T1N2M0 ⅡA,T3N3M0 ⅢB,T4 a N3M0 ⅢC,T4 a N3M0 ⅢC,T4 a N3M0 ⅢC,and T4 b N3M0 ⅢC.In conclusion,our study indicated that carbon nanoparticles failed to show good selectivity for metastatic lymph nodes;the result of lymphatic mapping does not achieve a satisfactory performance;the incidence of lymph node metastasis may increase,accompanying with the increase of the depth of cancer invasion;No.8p lymph node metastasis tends to occur for gastric carcinoma patients with the extent of lymph node metastasis over N2 stage.
基金funded by the National Key R&D Program of China(2024YFC2909400)the National Natural Science Foundation of China(42402180,42202195)the tackling applied science and technology projects of China National Petroleum Corporation(2023ZZ18)。
文摘Deep coal reservoirs(buried depth>2000 m)represent a significant yet underexploited resource for coalbed methane(CBM)production.In these reservoirs,CBM primarily exists in adsorbed and free phase,with the pore structure playing a critical role in gas storage and migration.The Jiaxian block in the northeastern Ordos Basin,has emerged as a key area for deep CBM exploration due to its promising resource potential.However,the pore structure characteristics of the No.8 coal seam in Jiaxian block and their implications for gas storage and production remain poorly understood.A comprehensive characterization of the No.8 coal seam's pore structure is conducted in the study using multiple methods including high-pressure mercury injection,N2/CO_(2)adsorption experiments,and integration of measured core gas content data and production history.The study results reveal that the pores can be mainly classified as vesicles and cellular pores,and the fractures are mainly static pressure fractures.Micropores(pore diameter<10 nm)dominate the pore system(accounting for more than 99%of the total specific surface area),providing important adsorption sites for gas storage.Although mesopores(pore diameter of 100-1000 nm)and macropores(pore diameter>1000 nm)account for a small proportion,they feature effective storage spaces and interconnectivity,resulting in a high proportion of free gas.Therefore,the reservoirs shows great development potential after stimulation(such as hydraulic fracturing).These findings emphasize the feasibility of large-scale and long-term development of CBM in the Jiaxian block in terms of reservoir space,gas content and production characteristics.This study serves to lay a scientific basis for its efficient exploitation.