In this paper the history of welding technology and the current status in China was reviewed, and based on the situation the developmental trend was prospected.
Ⅰ. GENERAL SITUATION The petrochemical industry is a technology and capital-intensive industry. The United States took the lead in the development of the petrochemical industry and started launching petrochemical pro...Ⅰ. GENERAL SITUATION The petrochemical industry is a technology and capital-intensive industry. The United States took the lead in the development of the petrochemical industry and started launching petrochemical projects in the 1930s and 1940s. The petrochemical industry in other developed countries, such as Germany, the United kingdom, France, Italy and Japan, began their development in the 1960s and 1970s.The petrochemical industry in these countries has played展开更多
As China expands its opening to the outside world, hotels in Beijing are developing rapidly. At the end of 1997, there were 259 hotels in Beijing, including 15 fivestar ones, 25 four-star ones and 46 three-star ones a...As China expands its opening to the outside world, hotels in Beijing are developing rapidly. At the end of 1997, there were 259 hotels in Beijing, including 15 fivestar ones, 25 four-star ones and 46 three-star ones and having more than 60,000 rooms.If hotels not appraised for star grade are taken into account, the hotel market in Beijing will be much larger.展开更多
1. History The vehicles with load capacity over 8 tons are classified as heavy vehicles according to China auto industry standards. The first 8t track, JN150, was made in 1960 by Jinan Auto Works. This COE, 4×2 t...1. History The vehicles with load capacity over 8 tons are classified as heavy vehicles according to China auto industry standards. The first 8t track, JN150, was made in 1960 by Jinan Auto Works. This COE, 4×2 truck, simple in structure, OK in technical展开更多
The sources,transportation and depositional processes of lacustrine mudrock are still poorly understood.Existing studies have demonstrated the controlling effect of astronomical forcing on lacustrine mudrock depositio...The sources,transportation and depositional processes of lacustrine mudrock are still poorly understood.Existing studies have demonstrated the controlling effect of astronomical forcing on lacustrine mudrock deposition,but its depositional mechanism and evolution are still not systematically investigated.Most research related to astronomical forcing exclusively highlights the sedimentation of carbonate rocks in deep-water lacustrine setting,with insufficient attention paid to the thick organic-rich,deep-lake mudrock.With the increasing interest in exploration and development of shale oil and gas accumulations,it is urgent to deeply understand depositional rules of lacustrine mudrock.This study reviews sediment sources,depositional mechanism and evolution process of mudrock through expounding the correlations between the periodic changes of astronomical forces,the parameters of Earth orbital and mudrock compositions.By investigating the existing literature and using some actual data of Jiyang Depression,Bohai Bay Basin in East China,this study expounds on the influence of astronomical cycles on the deposition of lacustrine mudrock.Moreover,efforts are made to analyze the effects of various orbital parameters(e.g.,precession,obliquity,and eccentricity with the periods ranging from tens of thousands years to million years)on the deposition of mudrock from small-scale(decimeters to meters)to large-scale(10s to 100s meters).Further,it is feasible to apply the high-precision isochronous stratigraphic correlation into clarifying the distribution of favorable shale oil and gas reservoirs.To conclude,this study enunciates the sedimentation of mudrock from a new perspective(astronomical forcing)and provides a direction for the research on sedimentation of fine-grained sedimentary rocks.展开更多
文摘In this paper the history of welding technology and the current status in China was reviewed, and based on the situation the developmental trend was prospected.
文摘Ⅰ. GENERAL SITUATION The petrochemical industry is a technology and capital-intensive industry. The United States took the lead in the development of the petrochemical industry and started launching petrochemical projects in the 1930s and 1940s. The petrochemical industry in other developed countries, such as Germany, the United kingdom, France, Italy and Japan, began their development in the 1960s and 1970s.The petrochemical industry in these countries has played
文摘As China expands its opening to the outside world, hotels in Beijing are developing rapidly. At the end of 1997, there were 259 hotels in Beijing, including 15 fivestar ones, 25 four-star ones and 46 three-star ones and having more than 60,000 rooms.If hotels not appraised for star grade are taken into account, the hotel market in Beijing will be much larger.
文摘1. History The vehicles with load capacity over 8 tons are classified as heavy vehicles according to China auto industry standards. The first 8t track, JN150, was made in 1960 by Jinan Auto Works. This COE, 4×2 truck, simple in structure, OK in technical
基金co-funded by the China National Key Research Project(Grant No.2017ZX05009-002)the National Natural Science Foundation of China(Grant Nos.41772090,41802130)the Foundation from Shandong Key Laboratory of Depositional Mineralization and Sedimentary Mineral,Shandong University of Science and Technology(Grant No.DMSM20190024)。
文摘The sources,transportation and depositional processes of lacustrine mudrock are still poorly understood.Existing studies have demonstrated the controlling effect of astronomical forcing on lacustrine mudrock deposition,but its depositional mechanism and evolution are still not systematically investigated.Most research related to astronomical forcing exclusively highlights the sedimentation of carbonate rocks in deep-water lacustrine setting,with insufficient attention paid to the thick organic-rich,deep-lake mudrock.With the increasing interest in exploration and development of shale oil and gas accumulations,it is urgent to deeply understand depositional rules of lacustrine mudrock.This study reviews sediment sources,depositional mechanism and evolution process of mudrock through expounding the correlations between the periodic changes of astronomical forces,the parameters of Earth orbital and mudrock compositions.By investigating the existing literature and using some actual data of Jiyang Depression,Bohai Bay Basin in East China,this study expounds on the influence of astronomical cycles on the deposition of lacustrine mudrock.Moreover,efforts are made to analyze the effects of various orbital parameters(e.g.,precession,obliquity,and eccentricity with the periods ranging from tens of thousands years to million years)on the deposition of mudrock from small-scale(decimeters to meters)to large-scale(10s to 100s meters).Further,it is feasible to apply the high-precision isochronous stratigraphic correlation into clarifying the distribution of favorable shale oil and gas reservoirs.To conclude,this study enunciates the sedimentation of mudrock from a new perspective(astronomical forcing)and provides a direction for the research on sedimentation of fine-grained sedimentary rocks.
