The carrier fluid (air or water) is used to transport solid material from the source place to its destination point through pipeline. Using air as carrier fluid to transport solid material through pipeline is called P...The carrier fluid (air or water) is used to transport solid material from the source place to its destination point through pipeline. Using air as carrier fluid to transport solid material through pipeline is called Pneumo transport, whereas transporting material with water or any other liquid through pipeline is called as hydraulic transport. A large number of installations are now available globally to transport solid materials to short, medium, and long distances using water/air as carrier fluid. However, the design of such system of pipeline is still an empirical art. In the present investigation, one generalized mathematical model developed by Shrivastava and Kar (SK Model) and CFD models were used and compared with experimental results for pneumatic and hydraulic transport of granular solids. The motivation of present work is to find the accuracy of SK model based on analytical, empirical and semi-empirical for the prediction of pressure drop and comparing the result with CFD based on mathematical equation for the mixture flow in the horizontal and vertical pipe lines. The comparison of pressure drop results obtained by using SK model and CFD model were validated with the experimental results for pneumatic and hydraulic transport of solids through. From the comparison results, it was observed that the results of pressure drop predicted by SK model are more accurate than the CFD models for all the cases considered.展开更多
Signal transducer and activator of transcription 3（STAT3） is a dual functional transcription factor with the functions of signal transduction and transcription regulation. It is reported that the expression of STAT3...Signal transducer and activator of transcription 3（STAT3） is a dual functional transcription factor with the functions of signal transduction and transcription regulation. It is reported that the expression of STAT3 in ovarian cancer is significantly higher and STAT3 can facilitate ovarian cancer growth and metastasis. To clarify the definite effect and molecular mechanism of STAT3 involved in ovarian cancer growth and metastasis, STAT3 expression was significantly downregulated by transfecting ovarian cancer model SK-OV-3 cells with the plasmid vector which express specific RNAi that targets human STAT3. The downregulated STAT3 not only decreased the invasion and migration but also inhibited the proliferation of SK-OV-3 cells. Western blot assay shows that the expression of vascular endothelial growth factor（VEGF） and that of Survivin were reduced in the cells with the plasma vector expressing specific RNAi that targets human STAT3. These results demonstrate that STAT3 involved in the invasion and migration of SK-OV-3 regulates the expression of VEGF and Survivin. In addition, VEGF and Survivin could play an important role in ovarian cancer growth and metastasis.展开更多
In situ U-Pb dating of carbonates is very common in the fields of mining and petroleum geology.However,carbonate minerals generally have low U,high common Pb,multiple generations,and uneven elemental distribution,ofte...In situ U-Pb dating of carbonates is very common in the fields of mining and petroleum geology.However,carbonate minerals generally have low U,high common Pb,multiple generations,and uneven elemental distribution,often resulting in relatively low dating precision.Hence,the success rate in U-Pb dating of carbonates by the traditional spot analysis method is generally low.This paper,through combining a mapping method for U-Pb dating with a proprietary visualization and analysis software,ChronoVA,conducted a comparison of the data obtained by both the spot analysis and the mapping method for 3carbonate standards and 2 unknown natural geological samples.We successfully developed a U-Pb dating method for carbonate rocks via LA-SF-ICP-MS elemental mapping and discussed the advantages and limitations of this method.Results show that in comparison with the traditional spot analysis method,the mapping approach has the following advantages:(1)reducing the downhole fractionation effect;(2)simplifying the analytical processes;(3)the elemental imaging data can help to identify multigeneration and mineral inclusions,ensuring the obtained carbonate U-Pb age having an interpretable geological meaning;(4)a large amount of mapping data can significantly improve the accuracy of the dating results.Despite these advantages,in carbonate samples with extremely high common Pb content and high Pb/U ratio,it might be difficult to obtain reliable ages even via the mapping method.In addition,it was understood that the carbonate standard WC-1,which is the most commonly used at present,could be inhomogeneous,and on occasion does not satisfy the SK model in spot analysis.展开更多
文摘The carrier fluid (air or water) is used to transport solid material from the source place to its destination point through pipeline. Using air as carrier fluid to transport solid material through pipeline is called Pneumo transport, whereas transporting material with water or any other liquid through pipeline is called as hydraulic transport. A large number of installations are now available globally to transport solid materials to short, medium, and long distances using water/air as carrier fluid. However, the design of such system of pipeline is still an empirical art. In the present investigation, one generalized mathematical model developed by Shrivastava and Kar (SK Model) and CFD models were used and compared with experimental results for pneumatic and hydraulic transport of granular solids. The motivation of present work is to find the accuracy of SK model based on analytical, empirical and semi-empirical for the prediction of pressure drop and comparing the result with CFD based on mathematical equation for the mixture flow in the horizontal and vertical pipe lines. The comparison of pressure drop results obtained by using SK model and CFD model were validated with the experimental results for pneumatic and hydraulic transport of solids through. From the comparison results, it was observed that the results of pressure drop predicted by SK model are more accurate than the CFD models for all the cases considered.
基金Supported by the Basis of Bethune Medical Research Fund of Jilin Province of China(No.200705114)
文摘Signal transducer and activator of transcription 3（STAT3） is a dual functional transcription factor with the functions of signal transduction and transcription regulation. It is reported that the expression of STAT3 in ovarian cancer is significantly higher and STAT3 can facilitate ovarian cancer growth and metastasis. To clarify the definite effect and molecular mechanism of STAT3 involved in ovarian cancer growth and metastasis, STAT3 expression was significantly downregulated by transfecting ovarian cancer model SK-OV-3 cells with the plasmid vector which express specific RNAi that targets human STAT3. The downregulated STAT3 not only decreased the invasion and migration but also inhibited the proliferation of SK-OV-3 cells. Western blot assay shows that the expression of vascular endothelial growth factor（VEGF） and that of Survivin were reduced in the cells with the plasma vector expressing specific RNAi that targets human STAT3. These results demonstrate that STAT3 involved in the invasion and migration of SK-OV-3 regulates the expression of VEGF and Survivin. In addition, VEGF and Survivin could play an important role in ovarian cancer growth and metastasis.
基金supported financially by the National Natural Science Foundation of China(Grant Nos.42472216,42273061 and U22B6002)the Science and Technology Development Program of Petro China Company Limited(Grant Nos.2023ZZ0206 and 2021DJ0105)。
文摘In situ U-Pb dating of carbonates is very common in the fields of mining and petroleum geology.However,carbonate minerals generally have low U,high common Pb,multiple generations,and uneven elemental distribution,often resulting in relatively low dating precision.Hence,the success rate in U-Pb dating of carbonates by the traditional spot analysis method is generally low.This paper,through combining a mapping method for U-Pb dating with a proprietary visualization and analysis software,ChronoVA,conducted a comparison of the data obtained by both the spot analysis and the mapping method for 3carbonate standards and 2 unknown natural geological samples.We successfully developed a U-Pb dating method for carbonate rocks via LA-SF-ICP-MS elemental mapping and discussed the advantages and limitations of this method.Results show that in comparison with the traditional spot analysis method,the mapping approach has the following advantages:(1)reducing the downhole fractionation effect;(2)simplifying the analytical processes;(3)the elemental imaging data can help to identify multigeneration and mineral inclusions,ensuring the obtained carbonate U-Pb age having an interpretable geological meaning;(4)a large amount of mapping data can significantly improve the accuracy of the dating results.Despite these advantages,in carbonate samples with extremely high common Pb content and high Pb/U ratio,it might be difficult to obtain reliable ages even via the mapping method.In addition,it was understood that the carbonate standard WC-1,which is the most commonly used at present,could be inhomogeneous,and on occasion does not satisfy the SK model in spot analysis.
