Based on the character of upward slicing backfilling mining and the condition of Gonggeyingzi coal mine in Inner Mongolia,this paper describes the studies of the strata behavior and the stress distribution in the proc...Based on the character of upward slicing backfilling mining and the condition of Gonggeyingzi coal mine in Inner Mongolia,this paper describes the studies of the strata behavior and the stress distribution in the process of backfilling mining in extra-thick coal seams.This was achieved by setting up and analyzing the elastic foundation beam model using the ABAQUS software.The results show that:(1) With the gradual mining of different slices,the roof appears to bend continuously but does not break.The vertical stress in the roof decreases and the decreasing amplitude reduces,while the tensile stress in the roof grows with the mining slices and the maximum tensile stress will not exceed the allowable tensile stress.(2) The front vertical stress at the working face exceeds the rear vertical stress and both show a trend of decrease with decreasing amplitude of decrease.(3) The slices mined early have more influence on the surrounding rock than the later ones.Similarly,the strata behavior experiences the same trend.The field measured data show that the roof does not break during the mining process,which is consistent with the conclusion.展开更多
On the basis of analyzing the fluid phase behavior during the transformation from gas reservoir to gas storage,a mathematical model and an experimental simulation method are established to describe the oil-gas phase b...On the basis of analyzing the fluid phase behavior during the transformation from gas reservoir to gas storage,a mathematical model and an experimental simulation method are established to describe the oil-gas phase behavior during the whole injection-production process of gas storage.The underground gas storage in the Liaohe Shuang 6 gas reservoir with oil rim is taken as a typical example to verify the reliability and accuracy of the mathematical model and reveal characteristics and mechanisms of fluid phase behavior.In the gas injection stage of the gas storage,the phase behavior is characterized by mainly evaporation and extraction and secondarily dissolution and diffusion of gas in the cap to oil in the oil rim of the reservoir;the gas in gas cap increases in light component content,decreases in contents of intermediate and heavy components,and increases in density and viscosity.The oil of the ring decreases in content of heavy components,increases in contents of light and intermediate components,decreases in density and viscosity,and increases in volume factor and solution gas oil ratio.In the stable operation stage of periodic injection-production of gas storage,the phase behavior shows that the evaporation and extraction capacity of injection gas in the cap to oil rim is weakened step by step,the phase behavior gradually changes into dissolution and diffusion.The gas in gas cap decreases in content of intermediate components,increases in content of light components slowly,and becomes lighter;but changes hardly in density and viscosity.The oil in the oil rim increases in content of heavy components,decreases in content of intermediate components,rises in density and viscosity,and drops in volume factor and solution gas oil ratio.展开更多
Purpose: This study aims to investigate and compare celebrity and ordinary users' behaviors on Sina Weibo. Design/methodology/approach: Data was collected from 12,555 ordinary users and 2,467 celebrity users on Sin...Purpose: This study aims to investigate and compare celebrity and ordinary users' behaviors on Sina Weibo. Design/methodology/approach: Data was collected from 12,555 ordinary users and 2,467 celebrity users on Sina Weibo. Correlation and regression analysis was performed on users' number of followings, number of followers and number of posts. Findings: The results revealed significant difference between famous and ordinary users' behaviors on Sina Weibo. We found correlation among ordinary users' number of followings, number of followers and number of posts, but for celebrity users, only their number of followings and number of posts are related with each other. For both ordinary and celebrity users, their number of followings significantly affects how many posts they publish. Research limitations: We only carried out our investigation on Sina Weibo and the findings need to be further verified on other microblogging platforms. Practical implications: This research is useful for microblogging service providers to understand different types of users and promote the continuous use of their services. Originality/value: This research delivers valuable insights into understanding of the characteristics of different types of microbloggers and the ways to increase user viscosity.展开更多
基金sponsored by the National Key Basic Research Program of China (No.2013CB227905)Qinglan Projects of Jiangsu Province
文摘Based on the character of upward slicing backfilling mining and the condition of Gonggeyingzi coal mine in Inner Mongolia,this paper describes the studies of the strata behavior and the stress distribution in the process of backfilling mining in extra-thick coal seams.This was achieved by setting up and analyzing the elastic foundation beam model using the ABAQUS software.The results show that:(1) With the gradual mining of different slices,the roof appears to bend continuously but does not break.The vertical stress in the roof decreases and the decreasing amplitude reduces,while the tensile stress in the roof grows with the mining slices and the maximum tensile stress will not exceed the allowable tensile stress.(2) The front vertical stress at the working face exceeds the rear vertical stress and both show a trend of decrease with decreasing amplitude of decrease.(3) The slices mined early have more influence on the surrounding rock than the later ones.Similarly,the strata behavior experiences the same trend.The field measured data show that the roof does not break during the mining process,which is consistent with the conclusion.
基金Supported by Scientific Research and Technology Development Project of PetroChina(KT2019-02-04,2021DJ1001).
文摘On the basis of analyzing the fluid phase behavior during the transformation from gas reservoir to gas storage,a mathematical model and an experimental simulation method are established to describe the oil-gas phase behavior during the whole injection-production process of gas storage.The underground gas storage in the Liaohe Shuang 6 gas reservoir with oil rim is taken as a typical example to verify the reliability and accuracy of the mathematical model and reveal characteristics and mechanisms of fluid phase behavior.In the gas injection stage of the gas storage,the phase behavior is characterized by mainly evaporation and extraction and secondarily dissolution and diffusion of gas in the cap to oil in the oil rim of the reservoir;the gas in gas cap increases in light component content,decreases in contents of intermediate and heavy components,and increases in density and viscosity.The oil of the ring decreases in content of heavy components,increases in contents of light and intermediate components,decreases in density and viscosity,and increases in volume factor and solution gas oil ratio.In the stable operation stage of periodic injection-production of gas storage,the phase behavior shows that the evaporation and extraction capacity of injection gas in the cap to oil rim is weakened step by step,the phase behavior gradually changes into dissolution and diffusion.The gas in gas cap decreases in content of intermediate components,increases in content of light components slowly,and becomes lighter;but changes hardly in density and viscosity.The oil in the oil rim increases in content of heavy components,decreases in content of intermediate components,rises in density and viscosity,and drops in volume factor and solution gas oil ratio.
文摘Purpose: This study aims to investigate and compare celebrity and ordinary users' behaviors on Sina Weibo. Design/methodology/approach: Data was collected from 12,555 ordinary users and 2,467 celebrity users on Sina Weibo. Correlation and regression analysis was performed on users' number of followings, number of followers and number of posts. Findings: The results revealed significant difference between famous and ordinary users' behaviors on Sina Weibo. We found correlation among ordinary users' number of followings, number of followers and number of posts, but for celebrity users, only their number of followings and number of posts are related with each other. For both ordinary and celebrity users, their number of followings significantly affects how many posts they publish. Research limitations: We only carried out our investigation on Sina Weibo and the findings need to be further verified on other microblogging platforms. Practical implications: This research is useful for microblogging service providers to understand different types of users and promote the continuous use of their services. Originality/value: This research delivers valuable insights into understanding of the characteristics of different types of microbloggers and the ways to increase user viscosity.