Current distribution in a drained aluminum reduction cell is critical due to its influence on the current efficiency, electrolysis stability, anodes and cathodes integrity. A finite element model was developed to simu...Current distribution in a drained aluminum reduction cell is critical due to its influence on the current efficiency, electrolysis stability, anodes and cathodes integrity. A finite element model was developed to simulate the electric field in a 75 kA drained aluminum reduction cell. The current distribution and influences of the cathode inclination angle and anode-cathode distance (ACD) were studied. The results show that relatively large horizontal current density appears in the aluminum film, and the maximum value reaches 600 kA/m2. As the cathode inclination angle increases from 2° to 15°, the maximum current density of the metal pad increases by 15%, while the maximum current density of the aluminum-wettable coating layer decreases by 27%. The influence of the ACD on the current distribution is not obvious.展开更多
Objective To find out a specific method for diagnosis of malignant pleural effusions (MPEs)with higher sensitivity and practicality. Methods The diagnosis of MPEs were made using density gradient cen-trifugation(DGC) ...Objective To find out a specific method for diagnosis of malignant pleural effusions (MPEs)with higher sensitivity and practicality. Methods The diagnosis of MPEs were made using density gradient cen-trifugation(DGC) , smear cytologic examination( SCE) and pleural needle biopsy (PNB). Comparisons between these results and those of benign pleural effusions were also made. Results The positive rates of DGC,SCE and PNB for diagnosing MPEs were 94. 3% ,62. 9% and 44. 6% , respectively, and the positive rate of SCE combined with PNB for diagnosing MPEs was 73. 2%. The positive rate of the exfoliative tumor cells ( ETCs ) by DGC was much higher than that of SCE or/and PNB with no false-positive. Conclusion The ETCs isolated by DGC from the MPEs is quite specific for the diagnosis of malignant tumors with higher sensitivity and practicality in clinico-patho-logical practice.展开更多
基金Project(2005CB623703) supported by the National Basic Research Program of China
文摘Current distribution in a drained aluminum reduction cell is critical due to its influence on the current efficiency, electrolysis stability, anodes and cathodes integrity. A finite element model was developed to simulate the electric field in a 75 kA drained aluminum reduction cell. The current distribution and influences of the cathode inclination angle and anode-cathode distance (ACD) were studied. The results show that relatively large horizontal current density appears in the aluminum film, and the maximum value reaches 600 kA/m2. As the cathode inclination angle increases from 2° to 15°, the maximum current density of the metal pad increases by 15%, while the maximum current density of the aluminum-wettable coating layer decreases by 27%. The influence of the ACD on the current distribution is not obvious.
文摘Objective To find out a specific method for diagnosis of malignant pleural effusions (MPEs)with higher sensitivity and practicality. Methods The diagnosis of MPEs were made using density gradient cen-trifugation(DGC) , smear cytologic examination( SCE) and pleural needle biopsy (PNB). Comparisons between these results and those of benign pleural effusions were also made. Results The positive rates of DGC,SCE and PNB for diagnosing MPEs were 94. 3% ,62. 9% and 44. 6% , respectively, and the positive rate of SCE combined with PNB for diagnosing MPEs was 73. 2%. The positive rate of the exfoliative tumor cells ( ETCs ) by DGC was much higher than that of SCE or/and PNB with no false-positive. Conclusion The ETCs isolated by DGC from the MPEs is quite specific for the diagnosis of malignant tumors with higher sensitivity and practicality in clinico-patho-logical practice.