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Retrieval of Land-surface Temperature from AMSR2 Data Using a Deep Dynamic Learning Neural Network 被引量:3
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作者 MAO Kebiao ZUO Zhiyuan +3 位作者 SHEN Xinyi XU Tongren GAO Chunyu LIU Guang 《Chinese Geographical Science》 SCIE CSCD 2018年第1期1-11,共11页
It is more difficult to retrieve land surface temperature(LST) from passive microwave remote sensing data than from thermal remote sensing data, because the emissivities in the passive microwave band can change more e... It is more difficult to retrieve land surface temperature(LST) from passive microwave remote sensing data than from thermal remote sensing data, because the emissivities in the passive microwave band can change more easily than those in the thermal infrared band. Thus, it is very difficult to build a stable relationship. Passive microwave band emissivities are greatly influenced by the soil moisture, which varies with time. This makes it difficult to develop a general physical algorithm. This paper proposes a method to utilize multiple-satellite, sensors and resolution coupled with a deep dynamic learning neural network to retrieve the land surface temperature from images acquired by the Advanced Microwave Scanning Radiometer 2(AMSR2), a sensor that is similar to the Advanced Microwave Scanning Radiometer Earth Observing System(AMSR-E). The AMSR-E and MODIS sensors are located aboard the Aqua satellite. The MODIS LST product is used as the ground truth data to overcome the difficulties in obtaining large scale land surface temperature data. The mean and standard deviation of the retrieval error are approximately 1.4° and 1.9° when five frequencies(ten channels, 10.7, 18.7, 23.8, 36.5, 89 V/H GHz) are used. This method can effectively eliminate the influences of the soil moisture, roughness, atmosphere and various other factors. An analysis of the application of this method to the retrieval of land surface temperature from AMSR2 data indicates that the method is feasible. The accuracy is approximately 1.8° through a comparison between the retrieval results with ground measurement data from meteorological stations. 展开更多
关键词 RADIOMETRY Advanced Microwave Scanning Radiometer 2 (AMSR2) passive remote sensing inverse problem
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Economical and Technical Indices of Decomposition Processes of Typical Rare Earth Minerals in China
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作者 Wang Weisheng Wang Songling +1 位作者 Jia Jiangtao Zhang Zhaobing 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第4期428-428,共1页
The typical treatment processes we of main rare earth resources in China, especially the economical and technical indices of the minerals decomposition of such as ionic adsorptive rare earth deposit ore, bastnasite an... The typical treatment processes we of main rare earth resources in China, especially the economical and technical indices of the minerals decomposition of such as ionic adsorptive rare earth deposit ore, bastnasite and mixed with monazite in Baotou, was presented. The dispersive ionic adsorptive rare earth deposit ore, which is enriched on valuable middle and heavy elements, concentrated by bicarbonate precipitation after exchanging with ammonium sulphate solution. Planting and waste liquid should be focused. Bastnasite and/or monazite, which is enriched light rare earth, centralized with high content and capacity,concentrated by gravimetric, magnetic, floating, then decomposed by calcinations and leaching. Waste liquid, gases and dregs should be treated properly. Investors interested in RE industry can find out the technical and economic characters and history of various RE minerals. Engineers and workers in RE industry can also find the differences of the plants, so as to make more efforts on improving management. However, solving environment protection problems for each process should be committed extraordinarily in order to make a sustainable development of RE industry. 展开更多
关键词 mineral decomposition economical and technique indices environment protection rare earths
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Innovation of China's Circular Agricultural Development in the Perspective of Low Carbon Economy 被引量:7
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作者 LI Yan-yan 《Asian Agricultural Research》 2011年第6期5-8,共4页
On the basis of the concept and characteristics of circular economy, this paper analyzes the restraining factors of China's circular agricultural development as follows: issues concerning agriculture, countryside ... On the basis of the concept and characteristics of circular economy, this paper analyzes the restraining factors of China's circular agricultural development as follows: issues concerning agriculture, countryside and farmers are outstanding; the problems of agricultural resources and agricultural ecological environment are serious; the quality of agricultural products cannot meet the demand of domestic and international market for food. Based on the internal requirements of low carbon economic development, this paper advances four innovative models concerning China's circular agricultural development as follows: the model of combining planting and breeding of agriculture, the developmental model of leisure and sightseeing, ecological integration model, and the developmental model of reusing agricultural byproducts. Every region should choose or create different circular agricultural model in different domains, in order to better use agricultural resources, reduce the consumption of agricultural energy inputs, reduce the emission of agricultural greenhouse gas, develop low carbon agriculture, and make great contribution for meeting the international challenges and promoting China's agricultural development. 展开更多
关键词 New village DEVELOPMENT Circular agriculture Low carbon economy China
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A study of sequence stratigraphy of the Early Cretaceous coal-bearing series in the southeastern Songliao Basin, NE China 被引量:1
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作者 Kai Shao Longyi Shao +3 位作者 Dongmin Ma Dongdong Wang Shuai Wang Di Gao 《International Journal of Coal Science & Technology》 EI 2020年第2期263-272,共10页
The Early Cretaceous is an important coal accumulation period in China.Abundant coal resources were formed in the southeastern margin of Songliao Basin.Sequence stratigraphy and coal accumulation of the Early Cretaceo... The Early Cretaceous is an important coal accumulation period in China.Abundant coal resources were formed in the southeastern margin of Songliao Basin.Sequence stratigraphy and coal accumulation of the Early Cretaceous in the southeastern margin of Songliao Basin have been studied on the basis of extensive outcrop and borehole data.Based on regional unconformity,basal erosional surfaces of incised valley fills,and abrupt depositional facies-reversal surface,six sequence boundaries have been identified,which subdivide the Early Cretaceous coal-bearing series into 5 third-order sequences.Sequence I corresponds to Huoshiling Formation,sequences II and III correspond to member I and member II of Shahezi Formation.Sequences IV and V correspond to member I and member II of Yingcheng Formation.Sequence I developed at the initial subsiding stage,sequence II and III developed during the stable subsiding stage,while sequence IV and V developed during the basin shrinkage stage.The major coal seams were developed in the sequence II and III,which ensured the relative balance between the increase rate of the accommodation space and the rate of peat accumulation for a longer period,thus forming a thick coal seam. 展开更多
关键词 Songliao Basin Sequence stratigraphy Depositional system Coal accumulation
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Modeling and Rendering in the Three-Dimensional Effect in Rhino for Lady's High Boots
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作者 王立新 李明辉 《Journal of Donghua University(English Edition)》 EI CAS 2011年第2期196-199,共4页
In recent years, the computer drawing technology that deals with three-dimensional (3D) design of footwear has become hot topics. Rhino is a kind of common and practical 3D design software with strong drawing and rend... In recent years, the computer drawing technology that deals with three-dimensional (3D) design of footwear has become hot topics. Rhino is a kind of common and practical 3D design software with strong drawing and rendering graphics function, which is widely used to design industrial products. In this paper, through decomposition and modeling, modeling and drawing methods were analyzed in various parts of footwear by Rhino, as well as the smooth technology and adjustments to its profile curve by an example of lady's high boots. Finally, through a series introductions of rendering effects for footwear in color, light perception, grain characteristic, and 3D graphics, the main technical essential is achieved and difficulties in design of overall footwear styles are solved. 展开更多
关键词 3D effect FOOTWEAR RHINO rendering and modeling
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Effects of soil properties on production and bioaccumulation of methylmercury in rice paddies at a mercury mining area,China 被引量:10
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作者 Deliang Yin Tianrong He +1 位作者 Runsheng Yin Lingxia Zeng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第6期194-205,共12页
Rice paddy soil is recognized as the hotspot of mercury(Hg) methylation, which is mainly a biotic process mediated by many abiotic factors. In this study, effects of key soil properties on the production and bioaccu... Rice paddy soil is recognized as the hotspot of mercury(Hg) methylation, which is mainly a biotic process mediated by many abiotic factors. In this study, effects of key soil properties on the production and bioaccumulation of Hg and methylmercury(MeHg) in Hg-contaminated rice paddies were investigated. Rice and soil samples were collected from the active Hg smelting site and abandoned Hg mining sites(a total of 124 paddy fields) in the Wanshan Mercury Mine, China. Total Hg(THg) and MeHg in soils and rice grains, together with sulfur(S),selenium(Se), organic matter(OM), nitrogen(N), phosphorus(P), mineral compositions(e.g., SiO2, Al2O3 and Fe2O3) and pH in soils were quantified. The results showed that long-term Hg mining activities had resulted in THg and MeHg contaminations in soil-rice system. The newly-deposited atmospheric Hg was more readily methylated relative to the native Hg already in soils, which could be responsible for the elevated MeHg levels in soils and rice grains around the active artificial Hg smelting site. The MeHg concentrations in soils and rice grains showed a significantly negative relationship with soil N/Hg, S/Hg and OM/Hg ratio possibly due to the formation of low-bioavailability Hg–S(N)–OM complexes in rhizosphere. The Hg–Se antagonism undoubtedly occurred in soil-rice system, while its role in bioaccumulation of MeHg in the MeHg-contaminated rice paddies was minor. However, other soil properties showed less influence on the production and bioaccumulation of MeHg in rice paddies located at the Wanshan Mercury Mine zone. 展开更多
关键词 Rice paddy Physicochemical property Mercury mining area MERCURY METHYLMERCURY Bioaccumulation factors
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The relationship between the growth process of the ferromanganese crusts in the Pacific seamount and Cenozoic ocean evolvement 被引量:2
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作者 DING Xuan GAO LianFeng +3 位作者 FANG NianQiao QU WenJun LIU Jian LI JiangShan 《Science China Earth Sciences》 SCIE EI CAS 2009年第8期1091-1103,共13页
Base on the Os isotope stratigraphy together with the empirical growth rate models using Co concentrations, the growth ages of the ferromanganese crusts MHD79 and MP3D10 distributed in the seamount of Pacific are conf... Base on the Os isotope stratigraphy together with the empirical growth rate models using Co concentrations, the growth ages of the ferromanganese crusts MHD79 and MP3D10 distributed in the seamount of Pacific are confirmed. Through the contrast and research on the previous achievements including ODP Leg 144 and the crusts CD29-2, N5E-06 and N1-15 of the seamount of the Central Pacific, the uniform five growth and growth hiatus periods of them are found, and closely related to the Cenozoic ocean evolvement process. In the Paleocene Carbon Isotope Maximum (PCIM), the rise of the global ocean productivity promoted the growth of the seamount crust; the first growth hiatus (I) of the ferromanganese crust finished. In the Paleocene-Eocene Thermal Maximum (PETM), though the vertical exchange of seawater was weakened, the strong terrestrial chemical weathering led to the input of a great amount of the terrigenous nutrients, which made the bioproductivity rise, so there were no crust hiatuses. During 52-50 Ma, the Early Eocene Optimum Climate (EECO), the two poles were warm, the latitudinal temperature gradient was small, the wind-driven sea circulation and upwelling activity were weak, the terrestrial weathering was also weakened, the open ocean bioproductivity decreased, and the ferromanganese crust had growth hiatus again (II). From early Middle Eocene-Late Eocene, Oligocene, it was a long-term gradually cooling process, the strengthening of the sea circulation and upwelling led to a rise of bioproductivity, and increase of the content of the hydrogenous element Fe, Mn and Co and the biogenous element Cu, Zn, so that was the most favorable stage for the growth of ferromanganese crust (growth periods III and IV) in the studied area. The hiatus III corresponded with the Eocene-Oligocene boundary, is inferred to relate with the global climate transformation, celestial body impact event in the Eocene-Oligocene transition. From the early to the middle Miocene, a large-scale growth hiatus (hiatus period IV) of the ferromanganese crust in the studied area is inferred to relate with temporary warm up climate and ephemeral withdrawal of Antarctic bottom water in the early Miocene. After that, the Antarctic ice sheets extended, the bottom water circumfluence strengthened, the ocean fertility increased, and the once interrupted crust continued to grow in the late Miocene (growth period V). 展开更多
关键词 PACIFIC SEAMOUNT ferromanganese crust GROWTH PERIOD and GROWTH hiatus PERIOD CENOZOIC OCEAN evolvement
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Global Water Vapor Content Decreases from 2003 to 2012: An Analysis Based on MODIS Data 被引量:7
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作者 MAO Kebiao CHEN Jingming +4 位作者 LI Zhaoliang MA Ying SONG Yang TAN Xuelan Yang Kaixian 《Chinese Geographical Science》 SCIE CSCD 2017年第1期1-7,共7页
Water vapor in the earth′s upper atmosphere plays a crucial role in the radiative balance, hydrological process, and climate change. Based on the latest moderate-resolution imaging spectroradiometer(MODIS) data, this... Water vapor in the earth′s upper atmosphere plays a crucial role in the radiative balance, hydrological process, and climate change. Based on the latest moderate-resolution imaging spectroradiometer(MODIS) data, this study probes the spatio-temporal variations of global water vapor content in the past decade. It is found that overall the global water vapor content declined from 2003 to 2012(slope b = –0.0149, R = 0.893, P = 0.0005). The decreasing trend over the ocean surface(b = –0.0170, R = 0.908, P = 0.0003) is more explicit than that over terrestrial surface(b = –0.0100, R = 0.782, P = 0.0070), more significant over the Northern Hemisphere(b = –0.0175, R = 0.923, P = 0.0001) than that over the Southern Hemisphere(b = –0.0123, R = 0.826, P = 0.0030). In addition, the analytical results indicate that water vapor content are decreasing obviously between latitude of 36°N and 36°S(b = 0.0224, R = 0.892, P = 0.0005), especially between latitude of 0°N and 36°N(b = 0.0263, R = 0.931, P = 0.0001), while the water vapor concentrations are increasing slightly in the Arctic regions(b = 0.0028, R = 0.612, P = 0.0590). The decreasing and spatial variation of water vapor content regulates the effects of carbon dioxide which is the main reason of the trend in global surface temperatures becoming nearly flat since the late 1990 s. The spatio-temporal variations of water vapor content also affect the growth and spatial distribution of global vegetation which also regulates the global surface temperature change, and the climate change is mainly caused by the earth's orbit position in the solar and galaxy system. A big data model based on gravitational-magmatic change with the solar or the galactic system is proposed to be built for analyzing how the earth's orbit position in the solar and galaxy system affects spatio-temporal variations of global water vapor content, vegetation and temperature at large spatio-temporal scale. This comprehensive examination of water vapor changes promises a holistic understanding of the global climate change and potential underlying mechanisms. 展开更多
关键词 water vapor content climate change moderate-resolution imaging spectroradiometer(MODIS)
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Global vegetation change analysis based on MODIS data in recent twelve years 被引量:2
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作者 毛克彪 Li Zhaoliang +4 位作者 Chen Jingming Ma Ying Liu Guang Tan Xuelan Yang Kaixian 《High Technology Letters》 EI CAS 2016年第4期343-349,共7页
Vegetation cover change is critical for understanding impacts and responses of vegetation to climate change. A study found that vegetation in the regions between 45°N-70°N was increasing using normalized dif... Vegetation cover change is critical for understanding impacts and responses of vegetation to climate change. A study found that vegetation in the regions between 45°N-70°N was increasing using normalized difference vegetation index( NDVI) from 1981 to 1991 ten years ago. The global vegetation growth has changed because of climate change in recent twelve years( 2001- 2012). After thorough analysis based on satellite data,it is found that it is evident that the global vegetation changed( NDVI) little,and it is increasing slightly in Northern hemisphere while it is decreasing slightly in Southern Hemisphere. For different latitudes,vegetation is increasing 0.17% every year from 60°N to 70 °N( R^2= 0.47,P > 0.013),while the vegetation is decreasing 0.11% every year from 10°N to 10° S( R^2= 0.54,P > 0.004). For different continents,the vegetation in South America is decreasing 0.16% every year( R^2= 0.78,P > 0.0001) and it is increasing 0.05% every year in Asia( R^2= 0.28,P > 0.072) and 0.25% every year in Oceania( R^2= 0.24,P > 0.1). The analysis of global vegetation in different seasons indicates that spatial distribution of global temperature and water vapor will affect the spatial distribution of vegetation,in turn,the spatial distribution of vegetation will also regulate the global temperature and water vapor spatial distribution at large scale. The growth and distribution of vegetation are mainly caused by the orbit of the celestial bodies,and a big data model based on gravitational-magmatic change with the solar or the galactic system as its center is proposed to be built for analyzing how the earth's orbit position in the solar and galaxy system affects spatial-temporal variations of global vegetation and temperature at large scale. These findings promise a holistic understanding of the global climate change and potential underlying mechanisms. 展开更多
关键词 VEGETATION GLOBAL climate change remote sensing
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Optimizing Nitrogen Fertilizer Application for Rice Production in the Taihu Lake Region,China 被引量:13
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作者 DENG Mei-Hua SHI Xiao-Jun +4 位作者 TIAN Yu-Hua YIN Bin ZHANG Shao-Lin ZHU Zhao-Liang S.D.KIMURA 《Pedosphere》 SCIE CAS CSCD 2012年第1期48-57,共10页
To determine the optimal amount of nitrogen(N) fertilizer for achieving a sustainable rice production at the Taihu Lake region of China,two-year on-farm field experiments were performed at four sites using various N a... To determine the optimal amount of nitrogen(N) fertilizer for achieving a sustainable rice production at the Taihu Lake region of China,two-year on-farm field experiments were performed at four sites using various N application rates.The results showed that 22%-30% of the applied N was recovered in crop and 7%-31% in soils at the rates of 100-350 kg N ha 1.Nitrogen losses increased with N application rates,from 44% of the applied fertilizer N at the rate of 100 kg N ha 1 to 69% of the N applied at 350 kg N ha 1.Ammonia volatilization and apparent denitrification were the main pathways of N losses.The N application rate of 300 kg N ha 1,which is commonly used by local farmers in the study region,was found to lead to a significant reduction in economic and environmental efficiency.Considering the cost for mitigating environmental pollution and the maximum net economic income,an application rate of 100-150 kg N ha 1 would be recommended.This recommended N application rate could greatly reduce N loss from 199 kg N ha 1 occurring at the N application rate of 300 kg N ha 1 to 80-110 kg N ha 1,with the rice grain yield still reaching 7 300-8 300 kg DW ha 1 in the meantime. 展开更多
关键词 economic efficiency environmental efficiency N application rate N loss rice grain yield
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