According to the characteristics of opencast coal resources and dragline technology system application in China,the structure and shifting step of transport passage are optimized in this paper.Typical coal transport p...According to the characteristics of opencast coal resources and dragline technology system application in China,the structure and shifting step of transport passage are optimized in this paper.Typical coal transport passage is analyzed in aspects such as the internal dump occupation,dragline operation efficiency,coal transport distance,upper stripping distance and shifting quantities.The middle passage should be given priority in thick overburden open pit mine because the dragline system is only responsible for part stripping task.According to characteristics of middle passage,the transport passage is divided into parallel climbing,vertical climbing and horizontal transport.In addition,the transport passage structure optimization model and shifting distance optimization model are established in this paper.The case study in Heidaigou open pit mine shows that,the parallel climbing height is accounted for about 60%of the total height,and reasonable shifting distances of the first mining area and the second mining area are 240 and 320 m.Sensitivity analysis shows that,the total passage height has important influence on the shifting step,so it is with the stripping height and passage construction cost to the passage structure.展开更多
The first World War caused a great advance in plastic surgery.that is,the surgery which improves the appearance.The New Zealand doctor,HaroldDell Gillies (born 1882),was one of the great plastic surgeons.This passage ...The first World War caused a great advance in plastic surgery.that is,the surgery which improves the appearance.The New Zealand doctor,HaroldDell Gillies (born 1882),was one of the great plastic surgeons.This passage istaken from the author’s book Great Moments in Medicine (1960),and it de-scribes some of Gillies’ problems.展开更多
Teaching analysis:1.Teaching objectives:(1)Language goals:(1)Key Words and Chunks;(2)Sentences:a.It's time to g raduate.b.I had problems with pronunciation and reading texts.c.This year,with Mr.Trent's help,my...Teaching analysis:1.Teaching objectives:(1)Language goals:(1)Key Words and Chunks;(2)Sentences:a.It's time to g raduate.b.I had problems with pronunciation and reading texts.c.This year,with Mr.Trent's help,my English level has been improving and I hope to get good grades at the end of the year.d.What are you looking forward to?(2)Ability goals:To lea d Ss to learn about the type and theme of a passage.To enable Ss to appreciate poem;(3)Emotional goals:To guide Ss to share good memories and express feelings about junior school life.To arouse Ss'love for school,friends and teachers To encou rage Ss to set a goal for the future;(4)Important and difficult teaching points:To enable Ss to understand and appreciate a r hyming poem.展开更多
The impacts of opening the Drake Passage(DP) on the oceanic general circulation are examined.When the DP is open,wind stress at mid-and high latitudes gives rise to a wind-driven gyre,which induces a meridional heat e...The impacts of opening the Drake Passage(DP) on the oceanic general circulation are examined.When the DP is open,wind stress at mid-and high latitudes gives rise to a wind-driven gyre,which induces a meridional heat exchange between mid-and high latitudes in the Southern Ocean.After the opening of the DP,the Antarctic Circumpolar Current(ACC) forms and its associated strong temperature front blocks the heat transport from mid-latitudes to high latitudes.A simple box model is formulated,in which the effects of the wind stress(for the case of DP closed) and the thermal front(for the case of DP open) on the variability of Antarctic Bottom Water(AABW) and North Atlantic Deep Water(NADW) are explored.The sensitivity experiments demonstrate that:(1) When the DP is closed,the enhancement of the wind-driven gyre leads to the decline of AABW formation in the Southern Ocean and the increase of NADW formation in the North Atlantic.As a result,water in high latitudes of the Southern Ocean becomes warmer,so does the bottom water of global ocean.(2) When the DP is open,there is no formation of AABW until the intensity of thermal front along ACC exceeds a threshold value(it is 4.03℃ in our model).Before the formation of AABW,temperature in most of the oceans is higher than that after the formation of AABW,which usually leads to the cooling of high latitudes of the Southern Hemisphere and the bottom water in global ocean.When the strength of the thermal front is lower than the critical value,there is no AABW formation,and temperature in most of the oceans is slightly higher.These results demonstrate that during the opening of the DP,changes in wind stress and the formation of the thermal front in the Southern Ocean can substantially affect the formation of AABW and NADW,thus changing the state of meridional overturning circulation in the global ocean.展开更多
Bringing The Agricultural Economy Up To Date With 22 percent of the total world population but only seven percent cultivatable land. feeding and clothing China's 1.2 billion people is an enormous task. The Chinese...Bringing The Agricultural Economy Up To Date With 22 percent of the total world population but only seven percent cultivatable land. feeding and clothing China's 1.2 billion people is an enormous task. The Chinese Government has always paid much attention to agriculture, particularly the "Rice Bag" and "Vegetable Basket" projects. In recent years, the total output of grain in China has basically stabilized展开更多
基金Financial support from the National High-Tech Research and Development Program of China(No.2012AA062004)the National Natural Science Foundation of China(No.51034005)
文摘According to the characteristics of opencast coal resources and dragline technology system application in China,the structure and shifting step of transport passage are optimized in this paper.Typical coal transport passage is analyzed in aspects such as the internal dump occupation,dragline operation efficiency,coal transport distance,upper stripping distance and shifting quantities.The middle passage should be given priority in thick overburden open pit mine because the dragline system is only responsible for part stripping task.According to characteristics of middle passage,the transport passage is divided into parallel climbing,vertical climbing and horizontal transport.In addition,the transport passage structure optimization model and shifting distance optimization model are established in this paper.The case study in Heidaigou open pit mine shows that,the parallel climbing height is accounted for about 60%of the total height,and reasonable shifting distances of the first mining area and the second mining area are 240 and 320 m.Sensitivity analysis shows that,the total passage height has important influence on the shifting step,so it is with the stripping height and passage construction cost to the passage structure.
文摘The first World War caused a great advance in plastic surgery.that is,the surgery which improves the appearance.The New Zealand doctor,HaroldDell Gillies (born 1882),was one of the great plastic surgeons.This passage istaken from the author’s book Great Moments in Medicine (1960),and it de-scribes some of Gillies’ problems.
文摘Teaching analysis:1.Teaching objectives:(1)Language goals:(1)Key Words and Chunks;(2)Sentences:a.It's time to g raduate.b.I had problems with pronunciation and reading texts.c.This year,with Mr.Trent's help,my English level has been improving and I hope to get good grades at the end of the year.d.What are you looking forward to?(2)Ability goals:To lea d Ss to learn about the type and theme of a passage.To enable Ss to appreciate poem;(3)Emotional goals:To guide Ss to share good memories and express feelings about junior school life.To arouse Ss'love for school,friends and teachers To encou rage Ss to set a goal for the future;(4)Important and difficult teaching points:To enable Ss to understand and appreciate a r hyming poem.
基金supported by National Basic Research Program of China(Grant No.2012CB957802)the Chinese Polar Environment Comprehensive Investigation & Assessment Programmes(Grant No.CHINARE2012-04-04)+1 种基金Program of International Science and Technology Cooperation(Grant No.S2011GR0348)National Natural Science Foundation of China(Grant No.41176029)
文摘The impacts of opening the Drake Passage(DP) on the oceanic general circulation are examined.When the DP is open,wind stress at mid-and high latitudes gives rise to a wind-driven gyre,which induces a meridional heat exchange between mid-and high latitudes in the Southern Ocean.After the opening of the DP,the Antarctic Circumpolar Current(ACC) forms and its associated strong temperature front blocks the heat transport from mid-latitudes to high latitudes.A simple box model is formulated,in which the effects of the wind stress(for the case of DP closed) and the thermal front(for the case of DP open) on the variability of Antarctic Bottom Water(AABW) and North Atlantic Deep Water(NADW) are explored.The sensitivity experiments demonstrate that:(1) When the DP is closed,the enhancement of the wind-driven gyre leads to the decline of AABW formation in the Southern Ocean and the increase of NADW formation in the North Atlantic.As a result,water in high latitudes of the Southern Ocean becomes warmer,so does the bottom water of global ocean.(2) When the DP is open,there is no formation of AABW until the intensity of thermal front along ACC exceeds a threshold value(it is 4.03℃ in our model).Before the formation of AABW,temperature in most of the oceans is higher than that after the formation of AABW,which usually leads to the cooling of high latitudes of the Southern Hemisphere and the bottom water in global ocean.When the strength of the thermal front is lower than the critical value,there is no AABW formation,and temperature in most of the oceans is slightly higher.These results demonstrate that during the opening of the DP,changes in wind stress and the formation of the thermal front in the Southern Ocean can substantially affect the formation of AABW and NADW,thus changing the state of meridional overturning circulation in the global ocean.
文摘Bringing The Agricultural Economy Up To Date With 22 percent of the total world population but only seven percent cultivatable land. feeding and clothing China's 1.2 billion people is an enormous task. The Chinese Government has always paid much attention to agriculture, particularly the "Rice Bag" and "Vegetable Basket" projects. In recent years, the total output of grain in China has basically stabilized
