By using the D-InSAR technique, we have acquired the temporal-spatial evolution images of preseismic.cosesimci-postseismic interferometric deformation fields associated with the M 7.9 earthquake of Mani, Tibet on 8 No...By using the D-InSAR technique, we have acquired the temporal-spatial evolution images of preseismic.cosesimci-postseismic interferometric deformation fields associated with the M 7.9 earthquake of Mani, Tibet on 8 November 1997. The analysis of these images reveals the relationships between the temporal-spatial evolution features of the interferometric deformation fields and locking, rupturing, and elastic restoring of the source rupture plane, which represent the processes of strain accumulation, strain release, and postseismic restoration. The result shows that 10 months prior to the Mani event, a left-lateral shear trend appeared in the seismic area, which was in accordance with the earthquake fault in nature. The quantity of local deformation on the north wall was slightly larger than that on the south wall, and the deformation distribution area of the north wall was relatively large. With the event impending, the deformation of the south wall varied increasingly, and the deformation center shifted eastward. Two and half monthd before the event, the west side of the fault was still locked while the east side began to slide, implying that the whole fault would rupture at any moment. These features can be regarded as short-term precursors to this earthquake. Within the period from 16 April 1996 to two and half months before the earthquake, the most remarkable deformation zones appeared in the north and south walls, which were parallel to and about 40 km apart from the fault, with accumulated local displacements of 344 mm and 251 mm on the north and south walls, respectively. The south wall was the active one with larger displacements. Five months after the earthquake, the distribution feature of interferometric fringes was just opposite to that prior to the event, expressing evident right-lateral shear. The recovered displacements are -179 mm on the north wall and -79 mm on the south wall, close to the east side of the fault. However, in the area of the south wall far from the fault there still existed a trend of sinistral motion. The deformation of the north wall was small but recovered fast in a larger area, while the active south wall began to recover from the east section of the fault toward the WSW.展开更多
The core of coal-derived gas theory is that coal measure is the gas source, and the hydrocarbon generation of coal measure is dominated by gas and supplemented by oil, so discoveries in related basins are dominated by...The core of coal-derived gas theory is that coal measure is the gas source, and the hydrocarbon generation of coal measure is dominated by gas and supplemented by oil, so discoveries in related basins are dominated by gas fields. Discovering and developing giant gas fields, especially those super giant gas fields with recoverable reserves more than 1×10^12 m^3, plays a key role in determining whether a country can be a major gas producing country with annual output over 500×10^8 m^3. The coal resource and coal-derived gas reserves are abundant and widespread in the world, and coal-derived gas makes a major contribution to the gas reserves and gas production in the world. By the end of 2017, 13 super giant coal-derived gas fields have been discovered in the world. The total initial recoverable reserves were 49.995 28×10^12 m^3, accounting for 25.8% of the total remaining recoverable reserves (193.5×10^12 m^3) in that year in the world. In 2017, there were 15 giant gas producing countries in the world, with a total gas yield of 28 567×10^8 m^3. Among them, six major coal-derived gas producing countries had a total gas yield of 11 369×10^8 m^3, accounting for 39.8% of total gas yield of major gas producing countries. The Urengoi gas field is a super giant coal-derived gas field with the most cumulative gas production in the world. By the end of 2015, the Urengoi gas field had cumulative gas production of 63 043.96×10^8 m^3, with the highest annual gas yield in the world. Its gas output was 3 300×10^8 m^3 in 1989, accounting for 41.4% and 15.7% of the gas output of Russia and the world, respectively. This study introduces the gas source rocks of the basins with super giant coal-derived gas fields in Russia, Turkmenistan, Netherlands, Mozambique and China, and their significances for these countries becoming giant gas producing countries in the world.展开更多
推动高校学生增值评价落地是一项系统、复杂的改革工程。美国考试服务中心增值评价的应用模式相对成熟,通过以大学生专业领域测试(Major Field Tests, MFT)为对象,沿着“设计概览—组织实施—数据分析—结果应用”的应用链路,在“质量...推动高校学生增值评价落地是一项系统、复杂的改革工程。美国考试服务中心增值评价的应用模式相对成熟,通过以大学生专业领域测试(Major Field Tests, MFT)为对象,沿着“设计概览—组织实施—数据分析—结果应用”的应用链路,在“质量、信誉、经费”三大运行保障下,进行高校学生增值评价的实践,形成以应用链路为前驱、以运行保障为后盾、以自身良性的运作基础为中枢的应用模式,实现增值评价改革工程告竣。鉴于美国高校学生增值评价的应用模式,提出三点建议:以专业化建设为起点,提高增值评价的水平和质量;以提升服务能力为手段,发挥增值评价的多元功能;以第三方评价机构介入为契机,提高增值评价的公信力。为推进我国大学生增值评价发展提供参考。展开更多
基金This work was supported by the National Natural Science Foundation of China (grants 40574007 and 40374013)he radar data used are partially offered by the project ENVISAT A0-711 of Europe Space Administration.
文摘By using the D-InSAR technique, we have acquired the temporal-spatial evolution images of preseismic.cosesimci-postseismic interferometric deformation fields associated with the M 7.9 earthquake of Mani, Tibet on 8 November 1997. The analysis of these images reveals the relationships between the temporal-spatial evolution features of the interferometric deformation fields and locking, rupturing, and elastic restoring of the source rupture plane, which represent the processes of strain accumulation, strain release, and postseismic restoration. The result shows that 10 months prior to the Mani event, a left-lateral shear trend appeared in the seismic area, which was in accordance with the earthquake fault in nature. The quantity of local deformation on the north wall was slightly larger than that on the south wall, and the deformation distribution area of the north wall was relatively large. With the event impending, the deformation of the south wall varied increasingly, and the deformation center shifted eastward. Two and half monthd before the event, the west side of the fault was still locked while the east side began to slide, implying that the whole fault would rupture at any moment. These features can be regarded as short-term precursors to this earthquake. Within the period from 16 April 1996 to two and half months before the earthquake, the most remarkable deformation zones appeared in the north and south walls, which were parallel to and about 40 km apart from the fault, with accumulated local displacements of 344 mm and 251 mm on the north and south walls, respectively. The south wall was the active one with larger displacements. Five months after the earthquake, the distribution feature of interferometric fringes was just opposite to that prior to the event, expressing evident right-lateral shear. The recovered displacements are -179 mm on the north wall and -79 mm on the south wall, close to the east side of the fault. However, in the area of the south wall far from the fault there still existed a trend of sinistral motion. The deformation of the north wall was small but recovered fast in a larger area, while the active south wall began to recover from the east section of the fault toward the WSW.
文摘Majority(MAJ)运算和反相(INV)运算组成完备集,数字逻辑电路可以用基于"MAJ/INV"的MI(Majority-Inverter)逻辑来实现。三输入MAJ门是MI逻辑电路的一种基本门电路单元。本文设计了一种基于碳纳米管场效应晶体管(Carbon Nanotube Field Effect Transistor,CNFET)的三输入MAJ门电路,并用所设计的MAJ门实现三个多输入组合逻辑电路。实验结果表明,在采用相同的器件和工艺的条件下,与现有的设计相比,所设计的MAJ门在功耗和功耗延时积上的改进最高分别达到32.5%和45.3%。
基金Supported by the National Natural Science Foundation of China(41472120)
文摘The core of coal-derived gas theory is that coal measure is the gas source, and the hydrocarbon generation of coal measure is dominated by gas and supplemented by oil, so discoveries in related basins are dominated by gas fields. Discovering and developing giant gas fields, especially those super giant gas fields with recoverable reserves more than 1×10^12 m^3, plays a key role in determining whether a country can be a major gas producing country with annual output over 500×10^8 m^3. The coal resource and coal-derived gas reserves are abundant and widespread in the world, and coal-derived gas makes a major contribution to the gas reserves and gas production in the world. By the end of 2017, 13 super giant coal-derived gas fields have been discovered in the world. The total initial recoverable reserves were 49.995 28×10^12 m^3, accounting for 25.8% of the total remaining recoverable reserves (193.5×10^12 m^3) in that year in the world. In 2017, there were 15 giant gas producing countries in the world, with a total gas yield of 28 567×10^8 m^3. Among them, six major coal-derived gas producing countries had a total gas yield of 11 369×10^8 m^3, accounting for 39.8% of total gas yield of major gas producing countries. The Urengoi gas field is a super giant coal-derived gas field with the most cumulative gas production in the world. By the end of 2015, the Urengoi gas field had cumulative gas production of 63 043.96×10^8 m^3, with the highest annual gas yield in the world. Its gas output was 3 300×10^8 m^3 in 1989, accounting for 41.4% and 15.7% of the gas output of Russia and the world, respectively. This study introduces the gas source rocks of the basins with super giant coal-derived gas fields in Russia, Turkmenistan, Netherlands, Mozambique and China, and their significances for these countries becoming giant gas producing countries in the world.
文摘推动高校学生增值评价落地是一项系统、复杂的改革工程。美国考试服务中心增值评价的应用模式相对成熟,通过以大学生专业领域测试(Major Field Tests, MFT)为对象,沿着“设计概览—组织实施—数据分析—结果应用”的应用链路,在“质量、信誉、经费”三大运行保障下,进行高校学生增值评价的实践,形成以应用链路为前驱、以运行保障为后盾、以自身良性的运作基础为中枢的应用模式,实现增值评价改革工程告竣。鉴于美国高校学生增值评价的应用模式,提出三点建议:以专业化建设为起点,提高增值评价的水平和质量;以提升服务能力为手段,发挥增值评价的多元功能;以第三方评价机构介入为契机,提高增值评价的公信力。为推进我国大学生增值评价发展提供参考。