The enrichment of chloride anion within the occluded cell （OC） for Type 304 austenitic stainless steel in low chloride concentration solution has been investigated by means of a simulated OC. The influence of the en...The enrichment of chloride anion within the occluded cell （OC） for Type 304 austenitic stainless steel in low chloride concentration solution has been investigated by means of a simulated OC. The influence of the enrichment of chloride anion on stress corrosion crack （SCC） of Type 304 stainless steel has been studied. It was observed that the amount of chloride anion migration was proportional to the charge flowing through the anode. Owning to the effects of enrichment of chloride anion, low chloride concentration solution could induce SCC for Type 304 stainless steel.展开更多
Using theoretical analysis, the single-phase gas seepage mathematical model influenced by slippage effects was established. The results show that the pressure of producing wells attenuates more violently than the well...Using theoretical analysis, the single-phase gas seepage mathematical model influenced by slippage effects was established. The results show that the pressure of producing wells attenuates more violently than the wells without slippage effects. The decay rate of reservoir pressure is more violent as the Klinkenherg factor increases. The gas prediction output gradually increases as the Klinenberg factor increases when considering gas slippage effects. Through specific examples, analyzed the law of stope pore pressure and gas output forecast changing in a hypotonic reservoir with slippage effects. The results have great theoretical significance in the study of the law of coal-bed methane migration in hypotonic reservoirs and for the exploitation of coal-bed methane.展开更多
Based on the overall analysis of the floating population among big and medium-sized cities in China,this paper, by means of statistics and questionnaires, makes a systematical study on the migratory features of the fl...Based on the overall analysis of the floating population among big and medium-sized cities in China,this paper, by means of statistics and questionnaires, makes a systematical study on the migratory features of the floating population in Mianyang, its employment structure, migrating causes and channels. According to the findings, the author finds a fact that with the strategy of Western Development, and with the construction of science and technology city of Mianyang, the migrating in Mianyang conforms to the general patterns of the migration, which has happened in those big and medium-sized cities in China.In addition,the city has a new but unique feature — economic factor, as the driving force of population migration, is quite distinct from that of those citiesin eastern areas of China.展开更多
The distribution characteristics of heavy metals in soil-root systems have great significance for the research into soil pollution risk assessment and the phytoremediation effect. This paper takes ligustrum lucidum as...The distribution characteristics of heavy metals in soil-root systems have great significance for the research into soil pollution risk assessment and the phytoremediation effect. This paper takes ligustrum lucidum as an example, based on the characteristics of adsorption of heavy metals in soil by woody plants, lays out sampling points, and using software Surer for the Kiging interpolation analysis, and the horizontal migration law of heavy metal cadmium in the soil-root interface system is simulated. Through multi-model statistical regression trend analysis, the horizontal migration mechanism of cadmium in different sections is discussed. The results show that： （1） under horizontal migration law： the migration ability of Cd is weaker near the Ligustrum lucidum root （0 30 cm）; with the root extension, the migration ability of Cd gradually is strengthened, and the main range of the migration ability is 60-90 cm. In addition, its migration law follows the cubic curve mode. （2） under longitudinal migration law： based on the Kriging method, migration models Z（hi） of heavy metal Cd in any depth of hi are constructed and fit the correlation coefficient R^2〉0.95.展开更多
In order to understand the migration law of respirable dust and gain reasonable design parameters for dust control on a super-long double-shearer fully mechanized working face, this paper describes research carried ou...In order to understand the migration law of respirable dust and gain reasonable design parameters for dust control on a super-long double-shearer fully mechanized working face, this paper describes research carried out using a numerical simulation package(Fluent) based on gas-solid coupling dispersed multiphase flow model and field measurement to research different technology modes, dust distribution law at different intervals where shearers work in opposite directions on the lower 9303 face, No. 2 Jining Mine,Yankuang Coal Mining Co. Results show that the concentration of dust 3–6 m away from the shearers working in the same directions was large, while the impact area of respirable dust near the shearer increased significantly to 5–6 m with the distance between two shearers working in opposite directions.The concentration of dust on a double-shearer face was considerably higher than that of a face with one shear under the combined effect of wind speed on the face and disturbed wind around the shearer, while the dust concentration near the shearer on the return side was considerably higher than that on the inlet side. The concentration of dust on a double-shearer face along the airflow declined slowly so that dust was hard to control. Simulation results confirmed the results of field measurement, which could provide reference for dust prevention design.展开更多
We consider a modified Markov branching process incorporating with both state-independent immigration-migration and resurrection. The effect of state-independent immigration-migration is firstly in- vestigated in deta...We consider a modified Markov branching process incorporating with both state-independent immigration-migration and resurrection. The effect of state-independent immigration-migration is firstly in- vestigated in detail. The explicit expressions for the extinction probabilities and mean extinction times are presented. The ergodicity and stability properties of the process incorporating with resurrection structure are then investigated. The conditions for recurrence, ergodicity and exponential ergodicity are obtained. An explicit expression for the equilibrium distribution is also presented. As a preparation, the criteria for regularity and uniqueness for such structure are firstly established.展开更多
文摘The enrichment of chloride anion within the occluded cell （OC） for Type 304 austenitic stainless steel in low chloride concentration solution has been investigated by means of a simulated OC. The influence of the enrichment of chloride anion on stress corrosion crack （SCC） of Type 304 stainless steel has been studied. It was observed that the amount of chloride anion migration was proportional to the charge flowing through the anode. Owning to the effects of enrichment of chloride anion, low chloride concentration solution could induce SCC for Type 304 stainless steel.
基金Supported by the Youth Program of the National Natural Science Foundation of China （51004061）
文摘Using theoretical analysis, the single-phase gas seepage mathematical model influenced by slippage effects was established. The results show that the pressure of producing wells attenuates more violently than the wells without slippage effects. The decay rate of reservoir pressure is more violent as the Klinkenherg factor increases. The gas prediction output gradually increases as the Klinenberg factor increases when considering gas slippage effects. Through specific examples, analyzed the law of stope pore pressure and gas output forecast changing in a hypotonic reservoir with slippage effects. The results have great theoretical significance in the study of the law of coal-bed methane migration in hypotonic reservoirs and for the exploitation of coal-bed methane.
文摘Based on the overall analysis of the floating population among big and medium-sized cities in China,this paper, by means of statistics and questionnaires, makes a systematical study on the migratory features of the floating population in Mianyang, its employment structure, migrating causes and channels. According to the findings, the author finds a fact that with the strategy of Western Development, and with the construction of science and technology city of Mianyang, the migrating in Mianyang conforms to the general patterns of the migration, which has happened in those big and medium-sized cities in China.In addition,the city has a new but unique feature — economic factor, as the driving force of population migration, is quite distinct from that of those citiesin eastern areas of China.
文摘The distribution characteristics of heavy metals in soil-root systems have great significance for the research into soil pollution risk assessment and the phytoremediation effect. This paper takes ligustrum lucidum as an example, based on the characteristics of adsorption of heavy metals in soil by woody plants, lays out sampling points, and using software Surer for the Kiging interpolation analysis, and the horizontal migration law of heavy metal cadmium in the soil-root interface system is simulated. Through multi-model statistical regression trend analysis, the horizontal migration mechanism of cadmium in different sections is discussed. The results show that： （1） under horizontal migration law： the migration ability of Cd is weaker near the Ligustrum lucidum root （0 30 cm）; with the root extension, the migration ability of Cd gradually is strengthened, and the main range of the migration ability is 60-90 cm. In addition, its migration law follows the cubic curve mode. （2） under longitudinal migration law： based on the Kriging method, migration models Z（hi） of heavy metal Cd in any depth of hi are constructed and fit the correlation coefficient R^2〉0.95.
基金the National Natural Science Foundation of China (No.51404249)the Basic Research Program of Jiangsu Province (No.BK20140201)the Priority Academic Program Development of Jiangsu Higher Education Institutions for financial support provided during this research
文摘In order to understand the migration law of respirable dust and gain reasonable design parameters for dust control on a super-long double-shearer fully mechanized working face, this paper describes research carried out using a numerical simulation package(Fluent) based on gas-solid coupling dispersed multiphase flow model and field measurement to research different technology modes, dust distribution law at different intervals where shearers work in opposite directions on the lower 9303 face, No. 2 Jining Mine,Yankuang Coal Mining Co. Results show that the concentration of dust 3–6 m away from the shearers working in the same directions was large, while the impact area of respirable dust near the shearer increased significantly to 5–6 m with the distance between two shearers working in opposite directions.The concentration of dust on a double-shearer face was considerably higher than that of a face with one shear under the combined effect of wind speed on the face and disturbed wind around the shearer, while the dust concentration near the shearer on the return side was considerably higher than that on the inlet side. The concentration of dust on a double-shearer face along the airflow declined slowly so that dust was hard to control. Simulation results confirmed the results of field measurement, which could provide reference for dust prevention design.
基金supported by National Natural Science Foundations of China (Grant Nos. 10771216 and 11071259)
文摘We consider a modified Markov branching process incorporating with both state-independent immigration-migration and resurrection. The effect of state-independent immigration-migration is firstly in- vestigated in detail. The explicit expressions for the extinction probabilities and mean extinction times are presented. The ergodicity and stability properties of the process incorporating with resurrection structure are then investigated. The conditions for recurrence, ergodicity and exponential ergodicity are obtained. An explicit expression for the equilibrium distribution is also presented. As a preparation, the criteria for regularity and uniqueness for such structure are firstly established.
