1.Objective Dunhuang Basin is the largest area and the third hydrocarbon resources potential basin among the basins of Hexi Corridor,and also a low exploration degree basin.The source rock position,characteristics and...1.Objective Dunhuang Basin is the largest area and the third hydrocarbon resources potential basin among the basins of Hexi Corridor,and also a low exploration degree basin.The source rock position,characteristics and hydrocarbon generating potential of residual Mid-Lower Jurassic are still unknown.The project is to ascertain the source rock development and hydrocarbon generating capacity of Mid-Lower Jurassic,to find out the resource potential,to delineate the resource prospect area and to optimize the favorable areas.It may direct the petroleum exploration in Dunhuang Basin.展开更多
Background: NCCN’s guidelines for the diagnosis and treatment of rectal cancer suggest that accurate preoperative clinical staging of rectal cancer is very important. Reliable preoperative evaluation is the key to th...Background: NCCN’s guidelines for the diagnosis and treatment of rectal cancer suggest that accurate preoperative clinical staging of rectal cancer is very important. Reliable preoperative evaluation is the key to the development of surgical protocols, in order to investigate the diagnostic value of digital rectal diagnosis for lymph node metastasis of middle and low rectal cancer. Methods: We prospectively performed digital rectal examination in 258 patients with mid-low rectal cancer before operation, to analyze the distance from the lower margin of the tumor to the margin of the anus, the diameter of the invasion of the intestinal wall of the tumor, the accuracy between the general type and depth of invasion of the tumor and the pathological results of the postoperative specimen, and the predictability of the lymph node metastasis rate of the rectal digital examination. Results: The results of the analysis showed that the above indicators and postoperative pathological findings have high accuracy. Conclusions: It is concluded that accurate and detailed digital rectal examination before operation can predict lymph node metastasis rate of mid-low rectal cancer at a higher level and accurately.展开更多
With diverse atmospheric circulation and complex mechanisms,typhoon remote rainstorms(TRR)are closely related to a variety of mid-low latitude systems.The anomalous signatures in such processes can improve forecasting...With diverse atmospheric circulation and complex mechanisms,typhoon remote rainstorms(TRR)are closely related to a variety of mid-low latitude systems.The anomalous signatures in such processes can improve forecasting heavy rainfall associated with typhoons and fill the gaps in current physical conceptual models of TRR.Using the optimal typhoon path dataset,ground observation data,and the National Centres for Environmental Prediction(NCEP)reanalysis dataset,the impact of anomalous water vapour transport on excessive rainfall in North China is investigated.The vector empirical orthogonal function(VEOF)analysis is applied to typhoon precipitation events from 1970 to 2021,and three major modes are extracted to reflect the anomalous water vapour transport for typhoon precipitation.Mode 1 reflects a moisture circulation pattern in North China due to the coexistence of typhoons and remote and direct precipitation,with the highest probability of heavy precipitation.The differences in remote precipitation areas and intensities are attributed to the location of typhoons in the western North Pacific and the shifting of the subtropical high ridge.To characterise the water vapour transport circulation of TRR in North China,we proposed the‘multivortex’idea.The transmission of the multi-vortex ensures a continuous supply of TRR water vapour,and the enhancement of the multi-vortex is significantly linked to the enhancement of remote precipitation.Three extreme northern rainstorms,75·8 Henan,7·21 Beijing,and 7·20 Zhengzhou rainstorms,have anomalous multi-vortex water vapour convergence,similar to Mode 1.The mechanism of water vapour driven by multi-vortex in the three severe rainstorm events is more extreme than in usual TRR events in North China.The stronger Indian low vortex and relatively southerly subtropical highs can intensify the southwest branch of the double water vapour transport branch,whereas the strengthening of typhoons in the western North Pacific facilitates water vapour transport through the channel on the southwestern side of the subtropical highs and then transports it to key rainstorm areas,promoting TRR development.Therefore,the combination of subtropical highs,typhoons,and the anomalous multi-vortex structure may help in the establishment of key indicators of extreme precipitation in North China.展开更多
NCEP/NCAR daily reanalysis data and Chinese daily gridded precipitation data are used to study the relationship between an aprupt drought-flood transition over the mid-low reaches of the Yangtze River in 2011 and the ...NCEP/NCAR daily reanalysis data and Chinese daily gridded precipitation data are used to study the relationship between an aprupt drought-flood transition over the mid-low reaches of the Yangtze River in 2011 and the intraseasonal oscillation （ISO; 30-60 days） in the mid-high latitude meridional circulation of the upper troposphere over East Asia. The abrupt transition from drought to flood occurs in early June. The first two recovered fields of the complex empirical orthogonal function show that northward-propagating westerlies from low latitudes converge with southward-propagating westerlies from high latitudes over the mid-low reaches of the Yangtze River （MLRYR） in mid late May. The timing of this convergence corresponds to the flood period in early-mid June. The ISO index is significantly and positively correlated with rainfall over the MLRYR. During the dry phase （before the transition）, the upper troposphere over the MLRYR is characterized by cyclonic flow, easterly winds, and convergence. The regional circulation is dominated by a wave train with a cyclone over east of Lake Baikal, an anticyclone over northern China, and a cyclone over the MLRYR. During the wet phase, the situation is reversed. The configuration of the wave train during the dry phase favors the southward propagation of westerly wind disturbances, while the configuration of the wave train during the wet phase favors the development and maintenance of a pumping effect and sustained ascending motions over the MLRYR.展开更多
Three generation systems, namely, steam Rankine cycle （SRC）, organic Rankine cycle （ORC）, and steam-organic combined Rankine cycle （S-ORC）, were simulated using the Engineering Equation Solver fEES） to efficien...Three generation systems, namely, steam Rankine cycle （SRC）, organic Rankine cycle （ORC）, and steam-organic combined Rankine cycle （S-ORC）, were simulated using the Engineering Equation Solver fEES） to efficiently utilize flue gas emissions from 200 to 450 ℃ in iron and steel plants. Based on the simulation results for thermal efficiency, exergy efficiency, and power generation, the performances of the three power generation systems were compared and analyzed. To further utilize waste heat from the turbine exhaust steam of the ORC system, cas- cade （）RC （CORC） was designed for heat sources above 300 ℃. Based on a comprehensive performance comparison, the application of the ORC using R141b is preferable for 200 to 300 ℃ flue gas. For 300 to 450 ℃ flue gas, CORC is an alternative technology to improve the efficiency and quality of waste heat utilization. For flue gas above 450 ℃, S-ORC can achieve higher efficiency and power generation than conventional SRC, with a relatively small negative pressure and high dryness of the turbine outlet steam. Hence, S-ORC can be considered as a substitute for SRC.展开更多
A continuous overcast-rainy weather(CORW) process occurred over the mid-lower reaches of the Yangtze River(MLRYR) in China from February 14 to March 9 in 2009,with a large stretch and long duration that was rarely see...A continuous overcast-rainy weather(CORW) process occurred over the mid-lower reaches of the Yangtze River(MLRYR) in China from February 14 to March 9 in 2009,with a large stretch and long duration that was rarely seen in historical records.Using the empirical orthogonal function(EOF),we analyzed the geopotential height anomaly field of the NCEP-DOE Reanalysis II in the same period,and defined the stable components of extended-range(10-30 days) weather forecast(ERWF).Furthermore,we defined anomalous and climatic stable components based on the variation characteristics of the variance contribution ratio of EOF components.The climatic stable components were able to explain the impact of climatically averaged information on the ERWF,and the anomalous stable components revealed the abnormal characteristics of the continuous overcast-rainy days.Our results show that the stable components,especially the anomalous stable components,can maintain the stability for a longer time(more than 10 days) and manifest as monthly scale low-frequency variation and ultra-long-wave activities.They also behave as ultra-long waves of planetary scale with a stable and vertically coherent structure,reflect the variation of general circulation in mid-high latitudes,display the cycle of the zonal circulation and the movement and adjustment of the ultra-long waves,and are closely linked to the surface CORW process.展开更多
目的:探讨应用腔镜直线切割吻合器(endoscopic linear cutters, ENDOPATH)行经肛门局部切除术治疗T_(1)期中低位直肠癌的疗效和安全性。方法:回顾性分析2011年01月至2017年12月我院收治的92例T_(1)期中低位直肠癌患者的临床资料。根据...目的:探讨应用腔镜直线切割吻合器(endoscopic linear cutters, ENDOPATH)行经肛门局部切除术治疗T_(1)期中低位直肠癌的疗效和安全性。方法:回顾性分析2011年01月至2017年12月我院收治的92例T_(1)期中低位直肠癌患者的临床资料。根据手术方式分为经肛门局部切除术组(TAE组)与直肠癌传统根治术组(根治术组)。TAE组使用腔镜直线切割吻合器行经肛门全层局部切除术,共39例;根治术组按全直肠系膜切除原则行传统根治术,共53例(包括16例Miles手术和37例Dixon手术)。对两组患者的一般资料、术中及术后相关指标及预后情况进行比较。结果:TAE组和根治术组患者在性别、年龄、肿瘤病理分型、肿瘤大小、距肛缘距离方面对比分析,无显著性差异(P>0.05),两组资料有可比性。两组患者在手术时间[(TAE组:(37.74±10.66)min,根治术组:(117.66±41.78)min]、术后住院时间[TAE组:(6.85±1.06)天,根治术组:(10.70±1.72)天]、术中出血量[TAE组:(30.21±2.97)mL,根治术组:(78.96±12.65)mL]、术后并发症发生率(TAE组:2.56%,根治术组:43.39%)方面差异均有统计学意义(P<0.01)。两组患者的3年无病生存率均为100.00%,两组患者3年内均无复发,相比较无统计学差异(P> 0.05)。两组患者的生存质量评分[TAE组:(90.31±3.82)分,根治术组:(71.59±6.33)分]差异有统计学意义(P<0.01)。结论:与传统根治术相比,应用腔镜直线切割吻合器对T1期中低位直肠癌行经肛门局部切除术同样安全有效。应用腔镜直线切割吻合器行经肛门局部切除术创伤小、并发症少、恢复快,患者术后生活质量等方面明显优于根治术。应用腔镜直线切割吻合器行经肛门局部切除术可作为早期无淋巴转移的中低位直肠癌患者优先选择的一种术式。展开更多
文摘1.Objective Dunhuang Basin is the largest area and the third hydrocarbon resources potential basin among the basins of Hexi Corridor,and also a low exploration degree basin.The source rock position,characteristics and hydrocarbon generating potential of residual Mid-Lower Jurassic are still unknown.The project is to ascertain the source rock development and hydrocarbon generating capacity of Mid-Lower Jurassic,to find out the resource potential,to delineate the resource prospect area and to optimize the favorable areas.It may direct the petroleum exploration in Dunhuang Basin.
文摘Background: NCCN’s guidelines for the diagnosis and treatment of rectal cancer suggest that accurate preoperative clinical staging of rectal cancer is very important. Reliable preoperative evaluation is the key to the development of surgical protocols, in order to investigate the diagnostic value of digital rectal diagnosis for lymph node metastasis of middle and low rectal cancer. Methods: We prospectively performed digital rectal examination in 258 patients with mid-low rectal cancer before operation, to analyze the distance from the lower margin of the tumor to the margin of the anus, the diameter of the invasion of the intestinal wall of the tumor, the accuracy between the general type and depth of invasion of the tumor and the pathological results of the postoperative specimen, and the predictability of the lymph node metastasis rate of the rectal digital examination. Results: The results of the analysis showed that the above indicators and postoperative pathological findings have high accuracy. Conclusions: It is concluded that accurate and detailed digital rectal examination before operation can predict lymph node metastasis rate of mid-low rectal cancer at a higher level and accurately.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP,2019QZKK0105)programmethe Development Fund of CAMS(2022KJ021).
文摘With diverse atmospheric circulation and complex mechanisms,typhoon remote rainstorms(TRR)are closely related to a variety of mid-low latitude systems.The anomalous signatures in such processes can improve forecasting heavy rainfall associated with typhoons and fill the gaps in current physical conceptual models of TRR.Using the optimal typhoon path dataset,ground observation data,and the National Centres for Environmental Prediction(NCEP)reanalysis dataset,the impact of anomalous water vapour transport on excessive rainfall in North China is investigated.The vector empirical orthogonal function(VEOF)analysis is applied to typhoon precipitation events from 1970 to 2021,and three major modes are extracted to reflect the anomalous water vapour transport for typhoon precipitation.Mode 1 reflects a moisture circulation pattern in North China due to the coexistence of typhoons and remote and direct precipitation,with the highest probability of heavy precipitation.The differences in remote precipitation areas and intensities are attributed to the location of typhoons in the western North Pacific and the shifting of the subtropical high ridge.To characterise the water vapour transport circulation of TRR in North China,we proposed the‘multivortex’idea.The transmission of the multi-vortex ensures a continuous supply of TRR water vapour,and the enhancement of the multi-vortex is significantly linked to the enhancement of remote precipitation.Three extreme northern rainstorms,75·8 Henan,7·21 Beijing,and 7·20 Zhengzhou rainstorms,have anomalous multi-vortex water vapour convergence,similar to Mode 1.The mechanism of water vapour driven by multi-vortex in the three severe rainstorm events is more extreme than in usual TRR events in North China.The stronger Indian low vortex and relatively southerly subtropical highs can intensify the southwest branch of the double water vapour transport branch,whereas the strengthening of typhoons in the western North Pacific facilitates water vapour transport through the channel on the southwestern side of the subtropical highs and then transports it to key rainstorm areas,promoting TRR development.Therefore,the combination of subtropical highs,typhoons,and the anomalous multi-vortex structure may help in the establishment of key indicators of extreme precipitation in North China.
基金Supported by the National Natural Science Foundation of China (41221064 and 40875052)China Meteorological Administration Special Public Welfare Research Fund (GYHY200906017 and GYHY201006020)Basic Research Fund of the Chinese Academy of Meteorological Sciences (2010Z003)
文摘NCEP/NCAR daily reanalysis data and Chinese daily gridded precipitation data are used to study the relationship between an aprupt drought-flood transition over the mid-low reaches of the Yangtze River in 2011 and the intraseasonal oscillation （ISO; 30-60 days） in the mid-high latitude meridional circulation of the upper troposphere over East Asia. The abrupt transition from drought to flood occurs in early June. The first two recovered fields of the complex empirical orthogonal function show that northward-propagating westerlies from low latitudes converge with southward-propagating westerlies from high latitudes over the mid-low reaches of the Yangtze River （MLRYR） in mid late May. The timing of this convergence corresponds to the flood period in early-mid June. The ISO index is significantly and positively correlated with rainfall over the MLRYR. During the dry phase （before the transition）, the upper troposphere over the MLRYR is characterized by cyclonic flow, easterly winds, and convergence. The regional circulation is dominated by a wave train with a cyclone over east of Lake Baikal, an anticyclone over northern China, and a cyclone over the MLRYR. During the wet phase, the situation is reversed. The configuration of the wave train during the dry phase favors the southward propagation of westerly wind disturbances, while the configuration of the wave train during the wet phase favors the development and maintenance of a pumping effect and sustained ascending motions over the MLRYR.
基金Sponsored by Science and Technology Commission Foundation of Jiangsu Province of China(BA2010035)
文摘Three generation systems, namely, steam Rankine cycle （SRC）, organic Rankine cycle （ORC）, and steam-organic combined Rankine cycle （S-ORC）, were simulated using the Engineering Equation Solver fEES） to efficiently utilize flue gas emissions from 200 to 450 ℃ in iron and steel plants. Based on the simulation results for thermal efficiency, exergy efficiency, and power generation, the performances of the three power generation systems were compared and analyzed. To further utilize waste heat from the turbine exhaust steam of the ORC system, cas- cade （）RC （CORC） was designed for heat sources above 300 ℃. Based on a comprehensive performance comparison, the application of the ORC using R141b is preferable for 200 to 300 ℃ flue gas. For 300 to 450 ℃ flue gas, CORC is an alternative technology to improve the efficiency and quality of waste heat utilization. For flue gas above 450 ℃, S-ORC can achieve higher efficiency and power generation than conventional SRC, with a relatively small negative pressure and high dryness of the turbine outlet steam. Hence, S-ORC can be considered as a substitute for SRC.
基金supported by National Natural Science Foundation of China (Grant No.40930952)Science and Technology Supporting Project (Grant No.2009BAC51B04)
文摘A continuous overcast-rainy weather(CORW) process occurred over the mid-lower reaches of the Yangtze River(MLRYR) in China from February 14 to March 9 in 2009,with a large stretch and long duration that was rarely seen in historical records.Using the empirical orthogonal function(EOF),we analyzed the geopotential height anomaly field of the NCEP-DOE Reanalysis II in the same period,and defined the stable components of extended-range(10-30 days) weather forecast(ERWF).Furthermore,we defined anomalous and climatic stable components based on the variation characteristics of the variance contribution ratio of EOF components.The climatic stable components were able to explain the impact of climatically averaged information on the ERWF,and the anomalous stable components revealed the abnormal characteristics of the continuous overcast-rainy days.Our results show that the stable components,especially the anomalous stable components,can maintain the stability for a longer time(more than 10 days) and manifest as monthly scale low-frequency variation and ultra-long-wave activities.They also behave as ultra-long waves of planetary scale with a stable and vertically coherent structure,reflect the variation of general circulation in mid-high latitudes,display the cycle of the zonal circulation and the movement and adjustment of the ultra-long waves,and are closely linked to the surface CORW process.
文摘目的:探讨应用腔镜直线切割吻合器(endoscopic linear cutters, ENDOPATH)行经肛门局部切除术治疗T_(1)期中低位直肠癌的疗效和安全性。方法:回顾性分析2011年01月至2017年12月我院收治的92例T_(1)期中低位直肠癌患者的临床资料。根据手术方式分为经肛门局部切除术组(TAE组)与直肠癌传统根治术组(根治术组)。TAE组使用腔镜直线切割吻合器行经肛门全层局部切除术,共39例;根治术组按全直肠系膜切除原则行传统根治术,共53例(包括16例Miles手术和37例Dixon手术)。对两组患者的一般资料、术中及术后相关指标及预后情况进行比较。结果:TAE组和根治术组患者在性别、年龄、肿瘤病理分型、肿瘤大小、距肛缘距离方面对比分析,无显著性差异(P>0.05),两组资料有可比性。两组患者在手术时间[(TAE组:(37.74±10.66)min,根治术组:(117.66±41.78)min]、术后住院时间[TAE组:(6.85±1.06)天,根治术组:(10.70±1.72)天]、术中出血量[TAE组:(30.21±2.97)mL,根治术组:(78.96±12.65)mL]、术后并发症发生率(TAE组:2.56%,根治术组:43.39%)方面差异均有统计学意义(P<0.01)。两组患者的3年无病生存率均为100.00%,两组患者3年内均无复发,相比较无统计学差异(P> 0.05)。两组患者的生存质量评分[TAE组:(90.31±3.82)分,根治术组:(71.59±6.33)分]差异有统计学意义(P<0.01)。结论:与传统根治术相比,应用腔镜直线切割吻合器对T1期中低位直肠癌行经肛门局部切除术同样安全有效。应用腔镜直线切割吻合器行经肛门局部切除术创伤小、并发症少、恢复快,患者术后生活质量等方面明显优于根治术。应用腔镜直线切割吻合器行经肛门局部切除术可作为早期无淋巴转移的中低位直肠癌患者优先选择的一种术式。
