Air pollution from shipping is becoming a critical issue,particularly in dense hub port cities.One proposed solution to minimize ship-based emissions at ports is the implementation of an Onshore Power Supply(OPS)syste...Air pollution from shipping is becoming a critical issue,particularly in dense hub port cities.One proposed solution to minimize ship-based emissions at ports is the implementation of an Onshore Power Supply(OPS)system.OPS allows ships to shut off their auxiliary engines and instead connect to the port grid.While there have been numerous studies conducted on ports in Europe and the United States,little research has been done on Egyptian ports.Therefore,this paper aims to investigate the feasibility of implementing OPS at Port Said West Port in Egypt,aligning with Egypt Vision 2030’s goals for addressing climate change.The research primarily focuses on analyzing data collected from calling ships to generate socio-economic and cost-effectiveness analyses of OPS.To further enhance the environmental benefits of OPS,the paper proposes the use of solar energy as the OPS electricity source.The findings of the study revealed that by relying on the national grid,emissions can be reduced by 28%.Moreover,it is predicted that this reduction could reach 100%if electricity generation is solely based on solar energy.Additionally,the economic analysis demonstrates promising profitability,with a payback period of approximately two years.展开更多
This paper presents a novel approach to model and simulate the multi-support depth-varying seismic motions（MDSMs） within heterogeneous offshore and onshore sites.Based on 1 D wave propagation theory,the three-dimens...This paper presents a novel approach to model and simulate the multi-support depth-varying seismic motions（MDSMs） within heterogeneous offshore and onshore sites.Based on 1 D wave propagation theory,the three-dimensional ground motion transfer functions on the surface or within an offshore or onshore site are derived by considering the effects of seawater and porous soils on the propagation of seismic P waves.Moreover,the depth-varying and spatial variation properties of seismic ground motions are considered in the ground motion simulation.Using the obtained transfer functions at any locations within a site,the offshore or onshore depth-varying seismic motions are stochastically simulated based on the spectral representation method（SRM）.The traditional approaches for simulating spatially varying ground motions are improved and extended to generate MDSMs within multiple offshore and onshore sites.The simulation results show that the PSD functions and coherency losses of the generated MDSMs are compatible with respective target values,which fully validates the effectiveness of the proposed simulation method.The synthesized MDSMs can provide strong support for the precise seismic response prediction and performance-based design of both offshore and onshore large-span engineering structures.展开更多
A winter onshore warm tongue extending from the Yellow Sea Warm Current to the southern Jiangsu coast, and an of fshore cold tongue extending from the southern Jiangsu coast to the southwest of Jeju Island(South Korea...A winter onshore warm tongue extending from the Yellow Sea Warm Current to the southern Jiangsu coast, and an of fshore cold tongue extending from the southern Jiangsu coast to the southwest of Jeju Island(South Korea), are newly identified based on the sea-surface temperature from satellite remote sensing, and further confirmed by the distribution of suspended sediments. In addition, there are two obvious thermal fronts associated with the onshore warm tongue and off shore cold tongue. The narrow gap between the two thermal fronts is supposed to be the pathway for the off shore transport of cold coastal water and suspended sediments. The concurrence of onshore warm and of fshore cold tongues suggests the concurrence of onshore and off shore currents in the western Yellow Sea in winter, which seems to be inconsistent with the previously accepted view that, in winter, the Yellow Sea Coastal Current flows from the Old Huanghe Delta to the southwest of Jeju Island. This distinctive phenomenon helps establish an updated view of the circulation in the western Yellow Sea in winter.展开更多
In-situ conversion processing (ICP) of shale oil underground at the depth ranging from 300 m to 3 000 m is a physical and chemical process caused by using horizontal drilling and electric heating technology, which con...In-situ conversion processing (ICP) of shale oil underground at the depth ranging from 300 m to 3 000 m is a physical and chemical process caused by using horizontal drilling and electric heating technology, which converts heavy oil, bitumen and various organic matter into light oil and gas in a large scale, which can be called"underground refinery". ICP has several advantages as in CO2capture, recoverable resource potential and the quality of hydrocarbon output. Based on the geothermal evolution mechanism of organic materials established by Tissot et al., this study reveals that in the nonmarine organic-rich shale sequence, the amount of liquid hydrocarbon maintaining in the shale is as high as 25%in the liquid hydrocarbon window stage (R o less than 1.0%), and the unconverted organic materials (low mature-immature organic materials) in the shale interval can reach 40%to 100%. The conditions of organic-rich shale suitable for underground in-situ conversion of shale oil should be satisfied in the following aspects, TOC higher than 6%, R o ranging between 0.5%and 1%, concentrated thickness of organic-rich shale greater than 15 meters, burial depth less than 3 000 m, covering area bigger than 50 km2, good sealing condition in both up-and down-contacting sequences and water content smaller than 5%, etc. The shale oil resource in China’s onshore region is huge. It is estimated with this paper that the technical recoverable resource reaches 70-90 billion tons of oil and 60-65 trillion cubic meters of gas. The ICP of shale oil underground is believed to be a fairway to find big oil in the source kitchen in the near future. And it is also believed to be a milestone to keep China long-term stability of oil and gas sufficient supply by putting ICP of shale oil underground into real practice in the future.展开更多
Different geophysical exploration methods have significant differences in terms of exploration depth,especially in frequency domain electromagnetic(EM)exploration.According to the definition of skin depth,this differe...Different geophysical exploration methods have significant differences in terms of exploration depth,especially in frequency domain electromagnetic(EM)exploration.According to the definition of skin depth,this difference will increase with the effective detection frequency of the method.As a result,when performing three-dimensional inversion on single type of EM data,it is not possible to effectively distinguish the subsurface geoelectric structure at the full scale.Therefore,it is necessary to perform joint inversion on different type of EM data.In this paper we combine the magnetotelluric method(MT)with the controlled-source audio-magnetotelluric method(CSAMT)to study the frequency-domain three-dimensional(3D)joint inversions,and we use the unstructured finite-element method to do the forward modeling for them,so that the numerical simulation accuracies of different electromagnetic methods can be satisfied.By combining the two sets of data,we can obtain the sensitivity of the electrical structure at different depths,and depict the full-scale subsurface geoelectric structures.In actual mineral exploration,the 3D joint inversion is more useful for identifying subsurface veins in the shallow part and blind mines in the deep part.It can delineate the morphological distribution of ore bodies more completely and provide reliable EM interpretations to guide the mining of minerals.展开更多
The inland lakes on the Tibetan Plateau are inhabited by diverse microbial communities,which play a significant role in biogeochemical cycles of biogenic elements(e.g.carbon,nitrogen).Onshore inputs provide essential
Successful breakthroughs have been made in shale oil exploration in several lacustrine basins in China,indicating a promising future for shale oil exploration and production.Current exploration results have revealed t...Successful breakthroughs have been made in shale oil exploration in several lacustrine basins in China,indicating a promising future for shale oil exploration and production.Current exploration results have revealed the following major conditions of lacustrine shale oil accumulation:(1)stable and widely distributed shale with a high organic abundance and appropriate thermal maturity acts as a fundamental basis for shale oil retention.This shale exhibits several critical parameters,such as total organic carbon content greater than 2%,with optimal values ranging from 3% to 4%,kerogen Ⅰ and Ⅱ_(1) as the dominant organic matter types,and vitrinite reflectance(R_(o))values greater than 0.9%(0.8% for brackish water environments).(2)Various types of reservoirs exhibiting brittleness and a certain volume of micro-nanoscale pores are critical conditions for shale oil accumulation,and these reservoirs have porosities greater than 3% to 6%.Moreover,when diagenesis is incipient,pure shales are not favorable for medium-to-high maturity shale oil enrichment,whereas tight sandstone and hybrid rocks with clay content less than 20% are favorable;however,for medium-to-late-stage diagenesis,pure shales with a clay content of 40% are favorable.(3)The retention of a large amount of high-quality hydrocarbons is the factor that best guarantees shale oil accumulation with good mobility.Free hydrocarbon content exceeding a threshold value of 2 mg/g is generally required,and the optimum value is 4 mg/g to 6 mg/g.Moreover,a gas-oil ratio exceeding a threshold value of 80 m^(3)/m^(3) is required,with the optimal value ranging from 150 m^(3)/m^(3) to 300 m^(3)/m^(3).(4)High-quality roof and floor sealing conditions are essential for the shale oil enrichment interval to maintain the overpressure and retain a sufficient amount of hydrocarbons with good quality.Lacustrine shale oil distributions exhibit the following characteristics:(1)major enrichment areas of shale oil are located in semi-deep to deep lacustrine depositional areas with external materials,such as volcanic ash fallout,hydrothermal solutions,and radioactive substances with catalytic action,as inputs;(2)intervals with“four high values and one preservation condition”govern the distribution of shale oil enrichment intervals;and(3)favorable assemblages of lithofacies/lithologies determine the distribution of enrichment area.According to preliminary estimates,China has 131×10^(8) to 163×10^(8) t of total shale oil resources with medium-to-high thermal maturity,among which 67×10^(8) to 84×10^(8) t is commercial.These resources are primarily located in the Chang 7^(1+2) interval in the Ordos Basin,Qing 1+2 members in Gulong sag in the Songliao Basin,Kongdian and Shahejie formations of Cangdong sag,Qikou sag and the Jiyang depression in the Bohai Bay Basin,and Lucaogou Formation in the Junggar Basin.展开更多
China's onshore petroleum in-dustry has achieved sat-isfactory results in its economic and technical cooperation with foreign countries as it 1S acce-lerating its economic reform and opening w1der to the outside w...China's onshore petroleum in-dustry has achieved sat-isfactory results in its economic and technical cooperation with foreign countries as it 1S acce-lerating its economic reform and opening w1der to the outside world.展开更多
The bidding blocks are distributed in different regions of China,There are seven blocks in W est China,and seven blocks in Northeast China,the other twelve blocks are from North and Central China.All the blocks are lo...The bidding blocks are distributed in different regions of China,There are seven blocks in W est China,and seven blocks in Northeast China,the other twelve blocks are from North and Central China.All the blocks are located in prospective sedimentary basins with different geological condi-tions,some are from oil produced basin such as Bohai Bay Basin which is a prolific basin,it's production accounts for 50%in total prodcuction of China.Based on estimation,the total potential resource of oil is 3.55 billion tons and gas is 800 billion cubic meters in bidding areas.As far as the exploratory objectives are concerned,there are Paleozoic.Mesozoic and Cenozoic strata,as well as continental clastic and marine一carbonate re-servoir.These provide more choices for foreign companies.In addition,most of bidding blocks are adjacent to transport lines,so communication and petroleum transportation are very convenient.展开更多
In this research the investigated parameters are given as below: The History of offshore and onshore construction is given where onshore structures as storage tanks and breakwaters with Estacada are mentioned with hie...In this research the investigated parameters are given as below: The History of offshore and onshore construction is given where onshore structures as storage tanks and breakwaters with Estacada are mentioned with hierarchical steps. To the offshore structures belong stationary fixed platforms (steel, concrete, combined, arctic) with floating (Jack-up, semi-submersibles, TLP,…) and pipe line construction. This issues are given as State-of-the-art and written as new examined innovative researches.展开更多
People all believe that in China there are very abundant wind energy resources and wind power can play quite an important role to substitute fossil energy resources. It is reported by some media that there are 2 TW of...People all believe that in China there are very abundant wind energy resources and wind power can play quite an important role to substitute fossil energy resources. It is reported by some media that there are 2 TW of wind energy resources in China, however, this f igure is somewhat doubtable.展开更多
The northernmost region of South America has great potential for wind energy production and is a strategic area for the energy transition.We analysed data from ERA5-Land global reanalysis from 1980 to 2020 to determin...The northernmost region of South America has great potential for wind energy production and is a strategic area for the energy transition.We analysed data from ERA5-Land global reanalysis from 1980 to 2020 to determine the wind power potential in this area.Our aim was to identify areas with a high potential for wind energy that could be used to supply energy in case of drought in the region or increases in fuel prices.We compared data from 19 meteorological stations located in Colombia with ERA5-Land reanalysis data to generate reliable information for the feasibility and operation of wind farms.According to our analysis,the Colombian Caribbean and Coastal Plain have monthly average wind speeds at 90 m ranging from 4.85 to 10.34 m/s and 3.79 to 6.62 m/s,respectively.Based on wind power density calculations,these regions have the highest wind power density in our study,with a monthly average of between 250 and 399 W/m^(2).The Caribbean Region had a 69%increase in wind power density from January to July compared with the annual average.The wind power density in the plains increased from January to March,while the Mountain Region had higher anomalies from May to October.The Alta Guajira and ParaguanáPeninsula have great potential to generate wind energy due to their privileged geographical location.Although ERA5 offers valuable information about wind availability in time and space,it cannot represent the influence of local effects on wind patterns for the Mountain Region.展开更多
文摘Air pollution from shipping is becoming a critical issue,particularly in dense hub port cities.One proposed solution to minimize ship-based emissions at ports is the implementation of an Onshore Power Supply(OPS)system.OPS allows ships to shut off their auxiliary engines and instead connect to the port grid.While there have been numerous studies conducted on ports in Europe and the United States,little research has been done on Egyptian ports.Therefore,this paper aims to investigate the feasibility of implementing OPS at Port Said West Port in Egypt,aligning with Egypt Vision 2030’s goals for addressing climate change.The research primarily focuses on analyzing data collected from calling ships to generate socio-economic and cost-effectiveness analyses of OPS.To further enhance the environmental benefits of OPS,the paper proposes the use of solar energy as the OPS electricity source.The findings of the study revealed that by relying on the national grid,emissions can be reduced by 28%.Moreover,it is predicted that this reduction could reach 100%if electricity generation is solely based on solar energy.Additionally,the economic analysis demonstrates promising profitability,with a payback period of approximately two years.
基金National Key R&D Program of China under Grant No.2016YFC0701108the State Key Program of National Natural Science Foundation of China under Grant No.51738007
文摘This paper presents a novel approach to model and simulate the multi-support depth-varying seismic motions（MDSMs） within heterogeneous offshore and onshore sites.Based on 1 D wave propagation theory,the three-dimensional ground motion transfer functions on the surface or within an offshore or onshore site are derived by considering the effects of seawater and porous soils on the propagation of seismic P waves.Moreover,the depth-varying and spatial variation properties of seismic ground motions are considered in the ground motion simulation.Using the obtained transfer functions at any locations within a site,the offshore or onshore depth-varying seismic motions are stochastically simulated based on the spectral representation method（SRM）.The traditional approaches for simulating spatially varying ground motions are improved and extended to generate MDSMs within multiple offshore and onshore sites.The simulation results show that the PSD functions and coherency losses of the generated MDSMs are compatible with respective target values,which fully validates the effectiveness of the proposed simulation method.The synthesized MDSMs can provide strong support for the precise seismic response prediction and performance-based design of both offshore and onshore large-span engineering structures.
基金Supported by the Strategy Program of Chinese Academy of Sciences(Nos.XDA10020104,XDA10020305)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(No.41421005)+2 种基金the National Natural Science Foundation of China(Nos.41476019,41606040)the NSFC-Shandong Joint Fund for Marine Science Research Centers(No.U1406401)the High Performance Computing Center,Institute of Oceanology,Chinese Academy of Sciences in Qingdao
文摘A winter onshore warm tongue extending from the Yellow Sea Warm Current to the southern Jiangsu coast, and an of fshore cold tongue extending from the southern Jiangsu coast to the southwest of Jeju Island(South Korea), are newly identified based on the sea-surface temperature from satellite remote sensing, and further confirmed by the distribution of suspended sediments. In addition, there are two obvious thermal fronts associated with the onshore warm tongue and off shore cold tongue. The narrow gap between the two thermal fronts is supposed to be the pathway for the off shore transport of cold coastal water and suspended sediments. The concurrence of onshore warm and of fshore cold tongues suggests the concurrence of onshore and off shore currents in the western Yellow Sea in winter, which seems to be inconsistent with the previously accepted view that, in winter, the Yellow Sea Coastal Current flows from the Old Huanghe Delta to the southwest of Jeju Island. This distinctive phenomenon helps establish an updated view of the circulation in the western Yellow Sea in winter.
基金Supported by the International Cooperation Project of China National Petroleum Corporation(2015D-4810-02)China National Science and Technology Major Project(2016ZX05046)
文摘In-situ conversion processing (ICP) of shale oil underground at the depth ranging from 300 m to 3 000 m is a physical and chemical process caused by using horizontal drilling and electric heating technology, which converts heavy oil, bitumen and various organic matter into light oil and gas in a large scale, which can be called"underground refinery". ICP has several advantages as in CO2capture, recoverable resource potential and the quality of hydrocarbon output. Based on the geothermal evolution mechanism of organic materials established by Tissot et al., this study reveals that in the nonmarine organic-rich shale sequence, the amount of liquid hydrocarbon maintaining in the shale is as high as 25%in the liquid hydrocarbon window stage (R o less than 1.0%), and the unconverted organic materials (low mature-immature organic materials) in the shale interval can reach 40%to 100%. The conditions of organic-rich shale suitable for underground in-situ conversion of shale oil should be satisfied in the following aspects, TOC higher than 6%, R o ranging between 0.5%and 1%, concentrated thickness of organic-rich shale greater than 15 meters, burial depth less than 3 000 m, covering area bigger than 50 km2, good sealing condition in both up-and down-contacting sequences and water content smaller than 5%, etc. The shale oil resource in China’s onshore region is huge. It is estimated with this paper that the technical recoverable resource reaches 70-90 billion tons of oil and 60-65 trillion cubic meters of gas. The ICP of shale oil underground is believed to be a fairway to find big oil in the source kitchen in the near future. And it is also believed to be a milestone to keep China long-term stability of oil and gas sufficient supply by putting ICP of shale oil underground into real practice in the future.
基金Supported by the National Natural Science Foundation of China(No.42074120).
文摘Different geophysical exploration methods have significant differences in terms of exploration depth,especially in frequency domain electromagnetic(EM)exploration.According to the definition of skin depth,this difference will increase with the effective detection frequency of the method.As a result,when performing three-dimensional inversion on single type of EM data,it is not possible to effectively distinguish the subsurface geoelectric structure at the full scale.Therefore,it is necessary to perform joint inversion on different type of EM data.In this paper we combine the magnetotelluric method(MT)with the controlled-source audio-magnetotelluric method(CSAMT)to study the frequency-domain three-dimensional(3D)joint inversions,and we use the unstructured finite-element method to do the forward modeling for them,so that the numerical simulation accuracies of different electromagnetic methods can be satisfied.By combining the two sets of data,we can obtain the sensitivity of the electrical structure at different depths,and depict the full-scale subsurface geoelectric structures.In actual mineral exploration,the 3D joint inversion is more useful for identifying subsurface veins in the shallow part and blind mines in the deep part.It can delineate the morphological distribution of ore bodies more completely and provide reliable EM interpretations to guide the mining of minerals.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41030211 and 41002123)the Scientific Research Funds for the 1000 "Talents" Program Plan from China University of Geosciences (Beijing)+1 种基金State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (No. GBL11201)the Fundamental Research Funds for National University, China University of Geosciences (Wuhan)
文摘The inland lakes on the Tibetan Plateau are inhabited by diverse microbial communities,which play a significant role in biogeochemical cycles of biogenic elements(e.g.carbon,nitrogen).Onshore inputs provide essential
基金Major Project of National Natural Science Foundation of China(42090020,42090025)Major Project of CNPC(2019E-2601)。
文摘Successful breakthroughs have been made in shale oil exploration in several lacustrine basins in China,indicating a promising future for shale oil exploration and production.Current exploration results have revealed the following major conditions of lacustrine shale oil accumulation:(1)stable and widely distributed shale with a high organic abundance and appropriate thermal maturity acts as a fundamental basis for shale oil retention.This shale exhibits several critical parameters,such as total organic carbon content greater than 2%,with optimal values ranging from 3% to 4%,kerogen Ⅰ and Ⅱ_(1) as the dominant organic matter types,and vitrinite reflectance(R_(o))values greater than 0.9%(0.8% for brackish water environments).(2)Various types of reservoirs exhibiting brittleness and a certain volume of micro-nanoscale pores are critical conditions for shale oil accumulation,and these reservoirs have porosities greater than 3% to 6%.Moreover,when diagenesis is incipient,pure shales are not favorable for medium-to-high maturity shale oil enrichment,whereas tight sandstone and hybrid rocks with clay content less than 20% are favorable;however,for medium-to-late-stage diagenesis,pure shales with a clay content of 40% are favorable.(3)The retention of a large amount of high-quality hydrocarbons is the factor that best guarantees shale oil accumulation with good mobility.Free hydrocarbon content exceeding a threshold value of 2 mg/g is generally required,and the optimum value is 4 mg/g to 6 mg/g.Moreover,a gas-oil ratio exceeding a threshold value of 80 m^(3)/m^(3) is required,with the optimal value ranging from 150 m^(3)/m^(3) to 300 m^(3)/m^(3).(4)High-quality roof and floor sealing conditions are essential for the shale oil enrichment interval to maintain the overpressure and retain a sufficient amount of hydrocarbons with good quality.Lacustrine shale oil distributions exhibit the following characteristics:(1)major enrichment areas of shale oil are located in semi-deep to deep lacustrine depositional areas with external materials,such as volcanic ash fallout,hydrothermal solutions,and radioactive substances with catalytic action,as inputs;(2)intervals with“four high values and one preservation condition”govern the distribution of shale oil enrichment intervals;and(3)favorable assemblages of lithofacies/lithologies determine the distribution of enrichment area.According to preliminary estimates,China has 131×10^(8) to 163×10^(8) t of total shale oil resources with medium-to-high thermal maturity,among which 67×10^(8) to 84×10^(8) t is commercial.These resources are primarily located in the Chang 7^(1+2) interval in the Ordos Basin,Qing 1+2 members in Gulong sag in the Songliao Basin,Kongdian and Shahejie formations of Cangdong sag,Qikou sag and the Jiyang depression in the Bohai Bay Basin,and Lucaogou Formation in the Junggar Basin.
文摘China's onshore petroleum in-dustry has achieved sat-isfactory results in its economic and technical cooperation with foreign countries as it 1S acce-lerating its economic reform and opening w1der to the outside world.
文摘The bidding blocks are distributed in different regions of China,There are seven blocks in W est China,and seven blocks in Northeast China,the other twelve blocks are from North and Central China.All the blocks are located in prospective sedimentary basins with different geological condi-tions,some are from oil produced basin such as Bohai Bay Basin which is a prolific basin,it's production accounts for 50%in total prodcuction of China.Based on estimation,the total potential resource of oil is 3.55 billion tons and gas is 800 billion cubic meters in bidding areas.As far as the exploratory objectives are concerned,there are Paleozoic.Mesozoic and Cenozoic strata,as well as continental clastic and marine一carbonate re-servoir.These provide more choices for foreign companies.In addition,most of bidding blocks are adjacent to transport lines,so communication and petroleum transportation are very convenient.
文摘In this research the investigated parameters are given as below: The History of offshore and onshore construction is given where onshore structures as storage tanks and breakwaters with Estacada are mentioned with hierarchical steps. To the offshore structures belong stationary fixed platforms (steel, concrete, combined, arctic) with floating (Jack-up, semi-submersibles, TLP,…) and pipe line construction. This issues are given as State-of-the-art and written as new examined innovative researches.
文摘People all believe that in China there are very abundant wind energy resources and wind power can play quite an important role to substitute fossil energy resources. It is reported by some media that there are 2 TW of wind energy resources in China, however, this f igure is somewhat doubtable.
基金supporting this study through the CON7872011 project.
文摘The northernmost region of South America has great potential for wind energy production and is a strategic area for the energy transition.We analysed data from ERA5-Land global reanalysis from 1980 to 2020 to determine the wind power potential in this area.Our aim was to identify areas with a high potential for wind energy that could be used to supply energy in case of drought in the region or increases in fuel prices.We compared data from 19 meteorological stations located in Colombia with ERA5-Land reanalysis data to generate reliable information for the feasibility and operation of wind farms.According to our analysis,the Colombian Caribbean and Coastal Plain have monthly average wind speeds at 90 m ranging from 4.85 to 10.34 m/s and 3.79 to 6.62 m/s,respectively.Based on wind power density calculations,these regions have the highest wind power density in our study,with a monthly average of between 250 and 399 W/m^(2).The Caribbean Region had a 69%increase in wind power density from January to July compared with the annual average.The wind power density in the plains increased from January to March,while the Mountain Region had higher anomalies from May to October.The Alta Guajira and ParaguanáPeninsula have great potential to generate wind energy due to their privileged geographical location.Although ERA5 offers valuable information about wind availability in time and space,it cannot represent the influence of local effects on wind patterns for the Mountain Region.
基金National Program on Key Basic Research Project (973 Program) (No. 2001CB209100)Doctoral Research Fund of Beijing University of Technology (52104001200701)
