Porous anodic oxide films were fabricated galvanostatically on titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate solution with different anodizing time.Scanning electron microscopy(SEM) and field emission scanning el...Porous anodic oxide films were fabricated galvanostatically on titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate solution with different anodizing time.Scanning electron microscopy(SEM) and field emission scanning electron microscopy(FE-SEM) were used to investigate the morphology evolution of the anodic oxide film.It is shown that above the breakdown voltage,oxygen is generated with the occurrence of drums morphology.These drums grow and extrude,which yields the compression stress.Subsequently,microcracks are generated.With continuous anodizing,porous oxides form at the microcracks.Those oxides grow and connect to each other,finally replace the microcrack morphology.The depth profile of the anodic oxide film formed at 1 800 s was examined by Auger electron spectroscopy(AES).It is found that the film is divided into three layers according to the molar fractions of elements.The outer layer is incorporated by carbon,which may come from electrolyte solution.The thickness of the outer layer is approximately 0.2-0.3 μm.The molar fractions of elements in the intermediate layer are extraordinarily stable,while those in the inner layer vary significantly with sputtering depth.The thicknesses of the intermediate layer and the inner layer are 2 μm and 1.0-1.5 μm,respectively.Moreover,the growth mechanism of porous anodic oxide films in neutral tartrate solution was proposed.展开更多
A novel flywheel energy storage （FES） motor/generator （M/G） was proposed for marine systems. The purpose was to improve the power quality of a marine power system （MPS） and strengthen the energy recycle. Two str...A novel flywheel energy storage （FES） motor/generator （M/G） was proposed for marine systems. The purpose was to improve the power quality of a marine power system （MPS） and strengthen the energy recycle. Two structures including the magnetic or non-magnetic inner-rotor were contrasted in the magnetostatic field by using finite element analysis （FEA）. By optimally designing the size parameters, the average speed of FEA results of was 17 200 r/m, and the current was controlled between 62 and 68 A in the transient field. The electrical machine electromagnetism design was further optimized by the FEA in the temperature field, to find the local overheating point under the normal operation condition and provide guidance for the cooling system. Finally, it can be concluded from the comprehensive physical field analysis that the novel redundant structure M/G can improve the efficiency of the M/G and maintain the stability of the MPS.展开更多
Numerous airports have been constructed based on the Twelfth Five-Year Plan for Civil Aviation Development of China. We collected relevant data on the number and distribution of civil airports, the construction of whi...Numerous airports have been constructed based on the Twelfth Five-Year Plan for Civil Aviation Development of China. We collected relevant data on the number and distribution of civil airports, the construction of which had started or that had been assessed and approved. Based on a comparative analysis of the limits of ecological restoration in different ecologically vulnerable areas from the perspective of space, as well as an examination of ecological sensitivity factors in the ecosystems surrounding airport construction projects, suggestions concerning key ecological control techniques to be employed in airport construction projects in different ecologically vulnerable areas are put forward. The results showed that the airport construction projects recently approved by the Ministry of Water Resources and the Environmental Protection Agency are mainly distributed in the ecologically vulnerable areas of the Red Soil Hilly Area in southern China, the Karst Rocky Desertification Area in southwest China, the Agro-pastoral Ecotone in the southwestern mountain region, and the Desert-Oasis Connecting Belt in northwest China. The airport construction projects in the southwest mountain area, the hilly areas of southern China, and in the Qinghai-Tibetan Plateau are mainly based on the ecological technologies of slope protection, interception and drainage management, and vegetation restoration, respectively. In the arid and semi-arid areas, the ecological control technology employed in airport construction is mainly the rational utilization of water resources and reduction or mitigation of the effects of sandstorms. This study aims to serve as basis for soil and water conservation plans in airport construction projects and accelerate ecosystem restoration within the vicinity of airport construction sites.展开更多
Payment for ecosystem services is a concept of environmental protection and method of environmental management that has ＂purchasing conservation＂ as a major feature and has grown around the world since the 1990 s. I...Payment for ecosystem services is a concept of environmental protection and method of environmental management that has ＂purchasing conservation＂ as a major feature and has grown around the world since the 1990 s. It is stressed by the school of environmental economics that as a voluntary mechanism of exchange between ecological service providers and demanders, payments for ecosystem services can help to increase inputs and improve efficiency. Ecological economics holds that the ecological system and the complexity of the policy environment restrict the functional space of market mechanisms. The negative influence of the objective of giving priority to efficiency on environmental protection and social fairness cannot be neglected; therefore, the exchange mechanism is just one type of eco-compensation models. Here, we posit that payments for ecosystem services is a good tool for environmental protection and increases inputs and efficiency. Although payment for ecosystem services is confronted with challenges in application, it is playing an increasingly important role in the field of ecological services with a relatively high degree of commodification. Payments for ecosystem services can also increase the cost effectiveness of publicly managed environmental projects with the cooperation of other policy tools.展开更多
基金Project(50571003) supported by the National Natural Science Foundation of China
文摘Porous anodic oxide films were fabricated galvanostatically on titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate solution with different anodizing time.Scanning electron microscopy(SEM) and field emission scanning electron microscopy(FE-SEM) were used to investigate the morphology evolution of the anodic oxide film.It is shown that above the breakdown voltage,oxygen is generated with the occurrence of drums morphology.These drums grow and extrude,which yields the compression stress.Subsequently,microcracks are generated.With continuous anodizing,porous oxides form at the microcracks.Those oxides grow and connect to each other,finally replace the microcrack morphology.The depth profile of the anodic oxide film formed at 1 800 s was examined by Auger electron spectroscopy(AES).It is found that the film is divided into three layers according to the molar fractions of elements.The outer layer is incorporated by carbon,which may come from electrolyte solution.The thickness of the outer layer is approximately 0.2-0.3 μm.The molar fractions of elements in the intermediate layer are extraordinarily stable,while those in the inner layer vary significantly with sputtering depth.The thicknesses of the intermediate layer and the inner layer are 2 μm and 1.0-1.5 μm,respectively.Moreover,the growth mechanism of porous anodic oxide films in neutral tartrate solution was proposed.
基金Supported by the Fundamental Research Funds for the Central Universities under Grants Nos. HEUCF101706 and HEUCF111705
文摘A novel flywheel energy storage （FES） motor/generator （M/G） was proposed for marine systems. The purpose was to improve the power quality of a marine power system （MPS） and strengthen the energy recycle. Two structures including the magnetic or non-magnetic inner-rotor were contrasted in the magnetostatic field by using finite element analysis （FEA）. By optimally designing the size parameters, the average speed of FEA results of was 17 200 r/m, and the current was controlled between 62 and 68 A in the transient field. The electrical machine electromagnetism design was further optimized by the FEA in the temperature field, to find the local overheating point under the normal operation condition and provide guidance for the cooling system. Finally, it can be concluded from the comprehensive physical field analysis that the novel redundant structure M/G can improve the efficiency of the M/G and maintain the stability of the MPS.
基金The National Key Research and Development Program of China(2016YFC0503704)
文摘Numerous airports have been constructed based on the Twelfth Five-Year Plan for Civil Aviation Development of China. We collected relevant data on the number and distribution of civil airports, the construction of which had started or that had been assessed and approved. Based on a comparative analysis of the limits of ecological restoration in different ecologically vulnerable areas from the perspective of space, as well as an examination of ecological sensitivity factors in the ecosystems surrounding airport construction projects, suggestions concerning key ecological control techniques to be employed in airport construction projects in different ecologically vulnerable areas are put forward. The results showed that the airport construction projects recently approved by the Ministry of Water Resources and the Environmental Protection Agency are mainly distributed in the ecologically vulnerable areas of the Red Soil Hilly Area in southern China, the Karst Rocky Desertification Area in southwest China, the Agro-pastoral Ecotone in the southwestern mountain region, and the Desert-Oasis Connecting Belt in northwest China. The airport construction projects in the southwest mountain area, the hilly areas of southern China, and in the Qinghai-Tibetan Plateau are mainly based on the ecological technologies of slope protection, interception and drainage management, and vegetation restoration, respectively. In the arid and semi-arid areas, the ecological control technology employed in airport construction is mainly the rational utilization of water resources and reduction or mitigation of the effects of sandstorms. This study aims to serve as basis for soil and water conservation plans in airport construction projects and accelerate ecosystem restoration within the vicinity of airport construction sites.
基金the National Science and Technology Support Program(2013BAC03B05)Monographic study of Graduate School of Chinese Academy of Social Sciences"Research of Eco-Compensation Experience in Developed Countries"
文摘Payment for ecosystem services is a concept of environmental protection and method of environmental management that has ＂purchasing conservation＂ as a major feature and has grown around the world since the 1990 s. It is stressed by the school of environmental economics that as a voluntary mechanism of exchange between ecological service providers and demanders, payments for ecosystem services can help to increase inputs and improve efficiency. Ecological economics holds that the ecological system and the complexity of the policy environment restrict the functional space of market mechanisms. The negative influence of the objective of giving priority to efficiency on environmental protection and social fairness cannot be neglected; therefore, the exchange mechanism is just one type of eco-compensation models. Here, we posit that payments for ecosystem services is a good tool for environmental protection and increases inputs and efficiency. Although payment for ecosystem services is confronted with challenges in application, it is playing an increasingly important role in the field of ecological services with a relatively high degree of commodification. Payments for ecosystem services can also increase the cost effectiveness of publicly managed environmental projects with the cooperation of other policy tools.
