The effects of Al-10Sr master alloys on grain refinement of AZ31 magnesium alloy were investigated,and the refinement efficiency of different Al-10Sr master alloys(commercial,solubilized,rolled and remelted+rapidly co...The effects of Al-10Sr master alloys on grain refinement of AZ31 magnesium alloy were investigated,and the refinement efficiency of different Al-10Sr master alloys(commercial,solubilized,rolled and remelted+rapidly cooled)was compared and analyzed.The results indicate that the morphology and size of Al4Sr phases in the microstructures of different Al-10Sr master alloys,are of great difference.For the commercial Al-10Sr master alloy,the Al4Sr phases evolve from coarse block shape to relatively fine block shape after being dissolved at 500 ℃ for 4 h and followed by water quenching;but after being rolled at 300 ℃ for 50% reduction or remelted and followed by rapid cooling,the Al4Sr phases mainly exhibit fine granule and fibre shapes.In addition,the different Al-10Sr master alloys can effectively reduce the grain size of AZ31 magnesium alloy,but their refinement efficiency is different.The refinement efficiency of the Al-10Sr master alloy obtained by remelting and rapid cooling is the best,then the rolled,solubilized and commercial Al-10Sr master alloys are in turn.The difference of refinement efficiency for different Al-10Sr master alloys may be related to the dissolution rates of Al4Sr phases with different morphologies and sizes in the melt of AZ31 magnesium alloy.展开更多
This article introduces the situation related with the increasingly deteriorating crude quality, the demand for cleaner transportation fuels and clean production processes that the world's petroleum refining industry...This article introduces the situation related with the increasingly deteriorating crude quality, the demand for cleaner transportation fuels and clean production processes that the world's petroleum refining industry is faced with. This article also suggests that the trend for future development of global refining industry is focused on the economy of scale for the refineries and the oil processing units, the refining structure readjustment, integration of the oil refining and chemical production and formation of oil refining bases. The oil refining industry will uninterruptedly rectify its industry allocation and processing unit configuration and strive for the reduction of production cost through technical progress and management innovations to reduce the production cost, boost the profitability and sharpen the market competitive edge.展开更多
In order to pursue the ideal criterion of "faithfulness, expressiveness, and elegance" initiated by the famous translator YAN-fu in translation and "accuracy, smoothness, and quickness" in interpretation in China,...In order to pursue the ideal criterion of "faithfulness, expressiveness, and elegance" initiated by the famous translator YAN-fu in translation and "accuracy, smoothness, and quickness" in interpretation in China, people have summarized some techniques to help the process. And generally speaking, trainers or teachers will introduce those techniques to the students respectively. Yet in this paper firstly, by taking examples from some of the text books and a few famous conferences in China, it makes a comparative analysis of the different techniques in translation and interpretation. The comparative analysis explores the most three common techniques: amplification, omission, and repetition in translation and interpretation, and draws the conclusion that translation is more formal, more rigorous, while interpretation is comparetively simple and flexiable. Based on the above analysis, then the paper suggests that the comparative analysis approaches should be used during the teaching process instead of the traditional one-way teaching.展开更多
基金Project(50725413)supported by the National Natural Science Foundation for Distinguished Young Scholar in ChinaProject(2007CB613704)supported by the National Basic Research Program of China
文摘The effects of Al-10Sr master alloys on grain refinement of AZ31 magnesium alloy were investigated,and the refinement efficiency of different Al-10Sr master alloys(commercial,solubilized,rolled and remelted+rapidly cooled)was compared and analyzed.The results indicate that the morphology and size of Al4Sr phases in the microstructures of different Al-10Sr master alloys,are of great difference.For the commercial Al-10Sr master alloy,the Al4Sr phases evolve from coarse block shape to relatively fine block shape after being dissolved at 500 ℃ for 4 h and followed by water quenching;but after being rolled at 300 ℃ for 50% reduction or remelted and followed by rapid cooling,the Al4Sr phases mainly exhibit fine granule and fibre shapes.In addition,the different Al-10Sr master alloys can effectively reduce the grain size of AZ31 magnesium alloy,but their refinement efficiency is different.The refinement efficiency of the Al-10Sr master alloy obtained by remelting and rapid cooling is the best,then the rolled,solubilized and commercial Al-10Sr master alloys are in turn.The difference of refinement efficiency for different Al-10Sr master alloys may be related to the dissolution rates of Al4Sr phases with different morphologies and sizes in the melt of AZ31 magnesium alloy.
文摘This article introduces the situation related with the increasingly deteriorating crude quality, the demand for cleaner transportation fuels and clean production processes that the world's petroleum refining industry is faced with. This article also suggests that the trend for future development of global refining industry is focused on the economy of scale for the refineries and the oil processing units, the refining structure readjustment, integration of the oil refining and chemical production and formation of oil refining bases. The oil refining industry will uninterruptedly rectify its industry allocation and processing unit configuration and strive for the reduction of production cost through technical progress and management innovations to reduce the production cost, boost the profitability and sharpen the market competitive edge.
文摘In order to pursue the ideal criterion of "faithfulness, expressiveness, and elegance" initiated by the famous translator YAN-fu in translation and "accuracy, smoothness, and quickness" in interpretation in China, people have summarized some techniques to help the process. And generally speaking, trainers or teachers will introduce those techniques to the students respectively. Yet in this paper firstly, by taking examples from some of the text books and a few famous conferences in China, it makes a comparative analysis of the different techniques in translation and interpretation. The comparative analysis explores the most three common techniques: amplification, omission, and repetition in translation and interpretation, and draws the conclusion that translation is more formal, more rigorous, while interpretation is comparetively simple and flexiable. Based on the above analysis, then the paper suggests that the comparative analysis approaches should be used during the teaching process instead of the traditional one-way teaching.