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Spatial Effect of Mineral Resources Exploitation on Urbanization:A Case Study of Tarim River Basin,Xinjiang,China 被引量:4
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作者 LI Xuemei ZHANG Xiaolei +1 位作者 DU Hongru CHU Shaolin 《Chinese Geographical Science》 SCIE CSCD 2012年第5期590-601,共12页
Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid areas.In this study,the spatial autocorrelation method and the spatial computation model were used... Mineral resources exploitation significantly affects the spatial structure and evolutive trend of urbanization in arid areas.In this study,the spatial autocorrelation method and the spatial computation model were used to investigate the spatial impacts of mineral resources excavation and processing on comprehensive level of urbanization in the Tarim River Basin,Xinjiang,China for the years of 2000,2006 and 2008.The results are as follows:1)There was a spatial correlation of the development of mineral resources industry and the comprehensive level of urbanization in 2006 and 2008,with the spatial concentration trend rising significantly in 2006 and decreasing in 2008.2)The patterns of local spatial concentration of mineral resources industry and of the comprehensive level of urbanization were relatively stable,and the two patterns showed signs of spatial correlationship.The higher was the degree of the concentration of mineral resources industry,the stronger was its impact on the spatial clustering of urbanization.3)In 2000, mineral resources excavation and processing had a significant positive impact on the comprehensive level of urbanization in the region but not in its adjacent regions.However,in 2008,mineral resources excavation and processing significantly raised the comprehensive level of urbanization not only in the region but also in its neighboring regions.This research demonstrates that the development of mineral resources industry can strongly affect the trends and spatial patterns of urbanization. 展开更多
关键词 mineral resources development URBANIZATION spatial effect Tarim River Basin
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Agricultural Non-point Source Pollution in China:Evaluation,Convergence Characteristics and Spatial Effects 被引量:4
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作者 QIU Wenwen ZHONG Zhangbao LI Zhaoliang 《Chinese Geographical Science》 SCIE CSCD 2021年第3期571-584,共14页
In this study,an inventory analysis approach was used to investigate the intensity of agricultural non-point source pollution(ANSP)and its spatial convergence at national and provincial levels in China from 1999 to 20... In this study,an inventory analysis approach was used to investigate the intensity of agricultural non-point source pollution(ANSP)and its spatial convergence at national and provincial levels in China from 1999 to 2017.On this basis,spatial factors affecting ANSP were explored by constructing a spatial econometric model.The results indicate that:1)The intensity of China's ANSP emission showed an overall upward trend and an obvious spatial difference,with the values being high in the eastern and central regions and relatively low in the western region.2)Significant spatial agglomeration was shown in China's ANSP intensity,and the agglomeration effect was increasing gradually.3)In the convergence analysis,a spatial lag model was found applicable for interpretation of the ANSP intensity,with the convergence rate being accelerated after considering the spatial factors but slower than that of regional economic growth.4)The spatial factors affecting the ANSP intensity are shown to be reduced by improving agricultural infrastructure investment,labor-force quality,and crop production ratio,while the expansion of agricultural economy scale and precipitation and runoff have positive impact on ANSP in the study region.However,agricultural research and development(R&D)investment showed no direct significant effect on the ANSP intensity.Meanwhile,improving the quality of the labor force would significantly reduce the ANSP intensity in the surrounding areas,while the precipitation and runoff would significantly increase the pollution of neighboring regions.This research has laid a theoretical basis for formulation and optimization of ANSP prevention strategies in China and related regions. 展开更多
关键词 intensity of agricultural non-point source pollution spatial effects inventory analysis spatial econometric model βconvergence
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Measurement of Rural Inclusive Financial Development and Analysis of Spatial Effects on Anti-poverty 被引量:2
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作者 Yongbin LU Chunmei WANG Weican QU 《Asian Agricultural Research》 2017年第1期33-40,46,共9页
Based on two dimensions of supply and demand,we use six indicators to establish a rural inclusive financial development index and evaluate the development of China's rural inclusive finance. We use spatial panel d... Based on two dimensions of supply and demand,we use six indicators to establish a rural inclusive financial development index and evaluate the development of China's rural inclusive finance. We use spatial panel data model to examine the relationship between financial inclusion and rural poverty. Results show that:( i) both the rural inclusive finance and rural residents' per capita consumption present spatial clustering feature and show significant spatial correlation;( ii) the development of rural inclusive finance has significant spatial effect on poverty alleviation along time and space dimensions. In this study,the paper puts forward policy recommendations on strengthening the rural financial resources flow and constructing diversified rural inclusive financial system. 展开更多
关键词 Inclusive financial Rural finance ANTI-POVERTY spatial effect
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Spatial Effect of Environmental Regulation on Carbon Emissions 被引量:3
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作者 Wang Min 《Meteorological and Environmental Research》 CAS 2018年第1期57-61,共5页
Based on Chinese provincial panel data from 2003 to 2014,the spatial dependence between the environment regulation and carbon emissions is tested by spatial autocorrelation analysis. Besides,spatial lag model and spat... Based on Chinese provincial panel data from 2003 to 2014,the spatial dependence between the environment regulation and carbon emissions is tested by spatial autocorrelation analysis. Besides,spatial lag model and spatial error model are built to empirically test the marginal effect of environmental regulation on carbon emissions and its spatial effect. The result shows that the influence trajectory of environmental regulation on carbon emissions performances inverted " U" type. It is " green paradox effect" before the inflection point and " reversed transmission reduction effect" after the inflection point. Moreover,the carbon emissions show significant spatial spillover effect. In order to achieve the desired effect of environmental regulation and promote carbon reduction,we should increase the environmental regulation intensity reasonably,select rational environmental regulation policy tools,and sufficiently consider the spatial spillover effect of carbon emissions. 展开更多
关键词 Environmental regulation Carbon emissions spatial effect
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Parametric modeling on spatial effect of excavation-damaged zone of underground cavern 被引量:1
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作者 刘会波 肖明 陈俊涛 《Journal of Central South University》 SCIE EI CAS 2013年第4期1085-1093,共9页
Regarding excavation-damaged zone (EDZ) around underground opening as non-homogeneous rockmass with spatial deterioration effect on stuffiness and strength, a parametric model of EDZ using radius-displacement-depend... Regarding excavation-damaged zone (EDZ) around underground opening as non-homogeneous rockmass with spatial deterioration effect on stuffiness and strength, a parametric model of EDZ using radius-displacement-dependent deformation modulus (RDDM) was proposed. Considering the nonlinearity characteristic of deformation and locality otherness of surrounding rock, deterioration parameter field of deformation modulus of rockmass around opening was quantitatively calculated through a given function. Applicability for multi-cavern condition and parameter sensibility of the model was analyzed by numerical experiments using synthetic data. Furthermore, the model was applied to identify EDZ of underground caverns of Pubugou hydropower station by calculating deterioration parameter field. Based on the parametric analysis of spatial effect and geological investigation, it is recognized that large radial deformation of deep fractured rock at the spandrel position and insufficient supporting bolts mainly result in great deformation pressure to act on the shotcrete and cause partial crack and spalling. It is shown that deterioration parameter field along the longitudinal axis of main powerhouse is evidently non-homogeneous in space and distributes exponentially along the radius from the opening. The model provides a simple and convenient way to identify the EDZ in the working state for rapid construction feedback analysis and support optimization of underground cavem from quantitative point of view and also aids in interpreting monitoring displacements and estimating support requirements. 展开更多
关键词 underground cavern excavation-damaged zone spatial effect parametric modeling deformation modulus
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Spatial Effect Research on Educational Output and Economic Growth in China
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作者 Wuyuan Sun Jiayun Ma 《Open Journal of Statistics》 2016年第3期387-396,共10页
This thesis is to study spatial effect of education output on economic growth through the use of spatial measurement technique. According to the study: there’s the presence of spatial spillover effects in human capit... This thesis is to study spatial effect of education output on economic growth through the use of spatial measurement technique. According to the study: there’s the presence of spatial spillover effects in human capital, economic growth, and others;in previous years, human capital depended on mainly the employers with junior school education or below;in recent years, with the reduction of employers with junior school education or below, employers with regular higher education can best promote the economic growth. However, it’s very difficult for human capital with vocational education to promote economic growth, especially in recent years. Therefore, from the perspective of long-term economic growth, China should focus on culturing professional talents and put more resources into the development of vocational education while developing the higher education. 展开更多
关键词 Educational Output Economic Growth spatial effect
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The Spatial Effect of Green Tax Policy on Energy Efficiency: Evidence from China
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作者 Deng Xiuyue Huang Hao 《Proceedings of Business and Economic Studies》 2020年第3期11-16,共6页
Based on the 30 provinces(cities,autonomous regions)panel data of China from 2007 to 2016,this paper establishes a Spatial Durbin Model to explore the spatial effects of green tax policies in broad and narrow sense on... Based on the 30 provinces(cities,autonomous regions)panel data of China from 2007 to 2016,this paper establishes a Spatial Durbin Model to explore the spatial effects of green tax policies in broad and narrow sense on energy efficiency.The results show that:(1)China's provincial energy efficiency has significant spatial correlation.(2)the relationship between the intensity of narrow sense green tax policy and the energy efficiency of the surrounding areas is an inverted U-shaped curve.(3)the relationship between the generalized green tax policy intensity and the energy efficiency of the surrounding areas is a U-shaped curve. 展开更多
关键词 Green tax policy Energy consumption ENVIRONMENT spatial effect
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Impact of digital economy development on carbon productivity:An empirical analysis based on threshold effect and spatial spillover effect
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作者 XING Huai-zhen YAO Jing 《Ecological Economy》 2024年第2期123-138,共16页
Utilizing provincial panel data from 2014 to 2020,this study employs a fixed effect model,a threshold effect model,and a spatial lag model to empirically examine the correlation between digital economic development an... Utilizing provincial panel data from 2014 to 2020,this study employs a fixed effect model,a threshold effect model,and a spatial lag model to empirically examine the correlation between digital economic development and carbon productivity.The findings indicate that digital economic development significantly contributes to the enhancement of carbon productivity in the long term.Furthermore,through instrumental variable method,replacement of explanatory variables and other methods to test its endogeneity and stability,the results remain robust.In terms of regional heterogeneity,the impact of digital economic development on carbon productivity is less pronounced in the central and western regions compared to the eastern region.Additionally,further investigation reveals that industrial structure upgrading and science and technology investment level exhibit different threshold effects on the influence of digital economy development level on carbon productivity.Moreover,there is a significant spatial spillover effect of digital economy development on carbon productivity with H-H and L-L agglomeration spatial correlation. 展开更多
关键词 digital economy carbon productivity threshold effect spatial spillover effect
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Geospatial Analysis of Urban Heat Island Effects and Tree Equity
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作者 Jillian Gorrell Sharon R. Jean-Philippe +3 位作者 Paul D. Ries Jennifer K. Richards Neelam C. Poudyal Rochelle Butler 《Open Journal of Forestry》 2024年第1期1-18,共18页
In recent decades, Urban Heat Island Effects have become more pronounced and more widely examined. Despite great technological advances, our current societies still experience great spatial disparity in urban forest a... In recent decades, Urban Heat Island Effects have become more pronounced and more widely examined. Despite great technological advances, our current societies still experience great spatial disparity in urban forest access. Urban Heat Island Effects are measurable phenomenon that are being experienced by the world’s most urbanized areas, including increased summer high temperatures and lower evapotranspiration from having impervious surfaces instead of vegetation and trees. Tree canopy cover is our natural mitigation tool that absorbs sunlight for photosynthesis, protects humans from incoming radiation, and releases cooling moisture into the air. Unfortunately, urban areas typically have low levels of vegetation. Vulnerable urban communities are lower-income areas of inner cities with less access to heat protection like air conditioners. This study uses mean evapotranspiration levels to assess the variability of urban heat island effects across the state of Tennessee. Results show that increased developed land surface cover in Tennessee creates measurable changes in atmospheric evapotranspiration. As a result, the mean evapotranspiration levels in areas with less tree vegetation are significantly lower than the surrounding forested areas. Central areas of urban cities in Tennessee had lower mean evapotranspiration recordings than surrounding areas with less development. This work demonstrates the need for increased tree canopy coverage. 展开更多
关键词 spatial Analysis Land Cover Urban Heat Island effect (UHIE) EVAPOTRANSPIRATION Tree Canopy Impervious Surface GIS Prediction Model GIS Machine Learning
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Spatial effect and resonance energy transfer for the construction of carbon dots composites with long-lived multicolor afterglow for advanced anticounterfeiting
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作者 Qian Cheng Zhiyuan Chen +4 位作者 Lai Hu Yuwei Song Senqiang Zhu Rui Liu Hongjun Zhu 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第8期208-212,共5页
Carbon dots(CDs)with room-temperature phosphorescence(RTP)have attracted dramatically growing interest in optical functional materials.However,the photoluminescence mechanism of CDs is still a vital and challenging to... Carbon dots(CDs)with room-temperature phosphorescence(RTP)have attracted dramatically growing interest in optical functional materials.However,the photoluminescence mechanism of CDs is still a vital and challenging topic.In this work,we prepared CD-based RTP materials via melting boric acid with various lengths of alkyl amine compounds as precursors.The spatial effect on the structure and the RTP properties of CDs were systematically investigated.With the increase in carbon chain length,the interplanar spacing of the carbon core expands and crosslink-enhanced emission weakens,resulting in a decrease in the phosphorescence intensity and lifetimes.Meanwhile,based on triplet-to-singlet resonance energy transfer,we employed intense and long-lived phosphorescence CDs as the donor and short-lived fluorescent dyes as the acceptor to achieve long-lived multicolor afterglow.By the triplet-to-singlet resonance energy transfer,the afterglow color can change from green to orange.The afterglow lifetimes are more than 0.9 s.Thanks to the outstanding afterglow properties,the composites were used for timeresolved and multiple-color advanced anticounterfeiting.This work will promote the design of multicolor and long-lived afterglow materials and expand their applications. 展开更多
关键词 Carbon dots spatial effect Resonance energy transfer MULTICOLOR Long-lived afterglow Anticounterfeiting
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Three-dimensional numerical simulation and earth pressure analysis on double-row piles with consideration of spatial effects 被引量:16
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作者 Zi-han WANG Jian ZHOU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2011年第10期758-770,共13页
As a new kind of technology in retaining structures, the characteristics of double-row piles are significantly affected by spatial effects. In this paper, double-row piles as a retaining structure are simulated numeri... As a new kind of technology in retaining structures, the characteristics of double-row piles are significantly affected by spatial effects. In this paper, double-row piles as a retaining structure are simulated numerically in three-dimension by finite element software PLAXIS 3D FOUNDATION. The behavior differences of piles in different positions around the foundation pit are analyzed. By changing the parameters, including the length-width ratio, the excavation depth, the distance between rows and the diameter of piles, the variations of the lateral deformation, the bending moment and the earth pressure around the piles are determined. The reasonable values of parameters and some suggestions with consideration of earth pressure are proposed for the design of double-row piles as a retaining structure. The results show that the lateral deformation and bending moment are the largest in the middle of long side of the foundation pit, which is identified as the most unfavorable position. It is indicated that the earth pressure between rows above pit bottom is close to active earth pressure, while the earth pressure between rows under pit bottom is close to static earth pressure. It is suggested that 1/2-2/3 of pile length, 0.6-1.2 m, 3d-6d, and 2d-2.5d be chosen as embedded depth of piles, diameter of piles, distance between rows, and distance between piles, respectively, where d is the pile diameter. 展开更多
关键词 Double-row piles Retaining structure spatial effect Finite element Earth pressure
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The measurement of the spatial effects of Chinese regional carbon emissions caused by exports 被引量:2
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作者 TANG Zhipeng 《Journal of Geographical Sciences》 SCIE CSCD 2015年第11期1328-1342,共15页
Based on the multi-regional input-output analysis, this paper improves the four traditional input-output formulas about exports resulting in multi-regional carbon emissions spatial effects which include direct effect,... Based on the multi-regional input-output analysis, this paper improves the four traditional input-output formulas about exports resulting in multi-regional carbon emissions spatial effects which include direct effect, indirect effect, spillover effect and feedback effect. And the latter two formulas are to measure the bidirectional influences of carbon emissions induced by regional exports between two regions. The results suggest that the direct effects of Chinese eight regions induced by national exports decreased from 1997 to 2010, and the indirect effects induced by national exports also decreased except the northern coastal region and the northwestern region in China. During this period, most of Chinese coastal regions had strong spillover effects induced by their own exports. The northern coastal region and the eastern coastal region had stronger feedback effects, while the southern coastal region had weaker feedback effects and Beijing-Tianjin region had the weakest feedback effect induced by their exports. All of the inland regions had strong feedback effects, especially for Northwest and Central China, induced by their exports. More attention should be paid to the inter-regional joint efforts in order to effectively achieve Chinese national carbon-reduction target. 展开更多
关键词 EXPORT region carbon emissions spatial effects INPUT-OUTPUT
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Characteristics and Spatial Effects of the Spatio-Temporal Pattern Evolution of Industrial Land in Xi'an 被引量:1
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作者 Zhao Dan Liu Kewei +2 位作者 Li Jianwei Pang Guowei Meng Yuanxu 《China City Planning Review》 CSCD 2022年第4期6-16,共11页
As an organic part of urban functions, industrial land is of great significance to the urban healthy and sustainable development. Although consensus has been reached on the evolutionary characteristics and spatial eff... As an organic part of urban functions, industrial land is of great significance to the urban healthy and sustainable development. Although consensus has been reached on the evolutionary characteristics and spatial effects of industrial land, the influence mechanism of the evolution of industrial land on urban space still needs further exploration. Therefore, the evolution of industrial land in Xi’an from 2003 to 2019 is analyzed by the land use change matrixes, mixed degrees index, and sprawl index according to the multisource data. The results show that the scale change of industrial land is characterized by an inverted U-shaped curve and development zone-oriented spatial aggregation. Suburbanization, the conversion of agricultural land to industrial land in the suburbs, has intensified urban sprawl, resulting in more serious work-living imbalance and traffic congestion.Deindustrialization, the conversion of industrial land to residential, commercial, and business facilities land in the city center, has promoted urban sprawl, generated a large amount of construction waste, and caused a waste of resources. Based on the complex factors such as urban planning, land finance, and development zones, this study contributes to the research of the improvement of the rationality of urban land layout by revealing the influence mechanism of the evolution of industrial land on urban space. 展开更多
关键词 industrial land SUBURBANIZATION DEINDUSTRIALIZATION spatial effect Xi’an
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Spatial spillover effects of transport infrastructure on regional economic growth
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作者 刘南 陈远高 周庆明 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期33-39,共7页
Spatial spillover effects,either positive or negative,of transport infrastructure,highways/expressways,etc.,on regional economic growth are proposed.Using the panel data for 11 cities of Zhejiang province from 1994 to... Spatial spillover effects,either positive or negative,of transport infrastructure,highways/expressways,etc.,on regional economic growth are proposed.Using the panel data for 11 cities of Zhejiang province from 1994 to 2003,a spatial production function is applied to examine the spatial spillovers which can be generated as a positive output spillover from the transport infrastructure between neighboring cities.Some spatial weighted matrices are adopted to define different neighboring cities to measure how easily factors or economic activities can migrate between regions.The estimation results show that the output elasticity of the highway infrastructure in 11 cities are all insignificant at a 5% significance level;hence,highway infrastructure in a region cannot explain the same region's economic growth.On the other hand,the highway infrastructure of other contiguous regions has positive spillover effects on a same region's economic growth. 展开更多
关键词 transport infrastructure HIGHWAY economic growth effects of spatial spillovers spatial weighted matrix
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The Spatial and Electronic Effects of Substituent Groups on the Thermal Curing of Bio-Based Benzoxazines
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作者 Rumeng Li Guozhu Zhan +4 位作者 Qi Ma Yunhe Yang Xiaoyun Liu Yitong Zhang Qixin Zhuang 《Journal of Renewable Materials》 SCIE EI 2021年第12期2093-2117,共25页
To explore the influence of substituent groups on thermally induced curing,eight new bio-based benzoxazines containing different substituent groups with different electron negativity and volumes were synthesized.The t... To explore the influence of substituent groups on thermally induced curing,eight new bio-based benzoxazines containing different substituent groups with different electron negativity and volumes were synthesized.The thermal curing of these bio-based benzoxazines was studied in detail.Combined with the curing reaction kinetics,simulation and calculation of Highest Occupied Molecular and Lowest Unoccupied Molecular values,the spatial and electronic effects of different substituent groups on the curing of benzoxazine was explored.It was found that when the substituent was located at the position directly connected to the N atom,the steric hindrance effect of the group was dominant.When the substituent group was located on the benzene ring connected to the O atom,both the electronic effect and the spatial effect influenced the curing of benzoxazine.When an electron-withdrawing group was connected ortho position to the O atom,the curing reaction was promoted due to the decreased electron cloud density of O-on the oxazine ring,making the C-O bond easier to break.When an electron-donating group was connected to the meta position of the O atom it also promoted the curing reaction,possibly because it increased the electron cloud density of the+CH2 reaction site and thereby facilitated electrophilic substitution via attack of+CH2 on the cross linking reaction centre.This work provides a deeper understanding of how spatial and electronic effects of substituents affect the curing of benzoxazine. 展开更多
关键词 BENZOXAZINE spatial effects electronic effects bio-based
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Grey spatial solitons due to two-photon photorefractive effect 被引量:35
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作者 张宇 侯春风 孙秀冬 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第1期159-164,共6页
This paper predicts that grey spatial solitons can exist in two-photon photorefractive materials. In steady state and undcr appropriate external bias conditions, it obtains the grey spatial soliton solutions of the op... This paper predicts that grey spatial solitons can exist in two-photon photorefractive materials. In steady state and undcr appropriate external bias conditions, it obtains the grey spatial soliton solutions of the optical wave evolution equation. The intensity profile, phase distribution, and transverse velocity of these grey solitons are discussed. 展开更多
关键词 photorefractive effect spatial soliton photorefractive material
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Low-carbon technology innovation responding to climate change from the perspective of spatial spillover effects 被引量:1
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作者 Weidong Wang Na Lu Caijing Zhang 《Chinese Journal of Population,Resources and Environment》 2018年第2期120-130,共11页
China's technological efforts to tackle climate change have lasted for many years. It is necessary to test the effect of these efforts with quantitative method. To be exact, whether and how China's low-carbon ... China's technological efforts to tackle climate change have lasted for many years. It is necessary to test the effect of these efforts with quantitative method. To be exact, whether and how China's low-carbon technology innovation responds to climate change should be tested. Based on the2004-2015 panel data of 30 provinces in China, we use the method of ESDA analyzing the spatial correlation of China's low-carbon innovation technology. Furthermore, we use the spatial Durbin model empirically analyzing the spatial spillover effects. The results obtained are as follows: first,supply and demand of Chinese low-carbon innovation has some deviation in the spatial distribution. The low-carbon technology innovation as the supply factor shows the characteristics of expanding from the east to the west. Innovation in eastern China has always been the most active, but innovative activities in the middle and western China are gradually decreased.However, carbon emissions have the characteristics of moving westward, implying the change of technology demand different from technology supply. Second, China's low-carbon innovation actively responds to the trend of climate change, indicating China's technological efforts have paid off. However, the spatial spillover effects are not significant, showing that the efforts in each region of China still work for himself. Third, environmental regulation and market pull are important factors for low-carbon technology innovation. Among them, both supporting policy and inhibitory policy have significant impact on the local low-carbon technology innovation, but no significant spatial spillover effects. It shows that environmental policies in different regions are competitive and lack of demonstration effects. Economic growth and export as market pull have higher level of effect on low-carbon technology innovation for both local and adjacent areas.Some policy implications are proposed based on these results finally. 展开更多
关键词 Low-carbon technology innovation climate change spatial spillover effects
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Energy consumption,air quality,and air pollution spatial spillover effects:evidence from the Yangtze River Delta of China 被引量:1
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作者 Lingyun He Lu Zhang Rongyan Liu 《Chinese Journal of Population,Resources and Environment》 2019年第4期329-340,共12页
Based on analysis of the theoretical impact of energy consumption on air quality,taking 20 heavily polluted cities in the Yangtze River Delta of China as the object,we construct a Spatial Dubin Model,and estimate the ... Based on analysis of the theoretical impact of energy consumption on air quality,taking 20 heavily polluted cities in the Yangtze River Delta of China as the object,we construct a Spatial Dubin Model,and estimate the effect of energy consumption on air quality and the spatial spillover effects of air pollution.We come to the following conclusions:First,the regional air quality has significant spatial dependence and spatial heterogeneity.Second,under three kinds of spatial associated mode,energy consumption has a negative impact on air quality,and the air pollution arising from energy consumption has a negative intra-regional spillover effect.The effect is strongest under the spatial distance weight matrix,followed by the economic distance,and the adjacent spatial weight matrix,which are−0.7926,−0.4547,and−0.4539,respectively.Third,in addition,under the adjacent space and economic distance space matrix,energy consumption has a significant negative effect on air quality,and the inter-regional spillover effects are−0.1513 and−2.5736,respectively.Meanwhile,considering spatial distance and economic development,the inter-regional spillover effect is much larger than is the intra-regional spillover effect.In general,the total spillover effect is at−0.6053 and−3.0284. 展开更多
关键词 Energy consumption air quality spatial spillover effect Yangtze River Delta
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Seasonal and Spatial Variation of Radiative Effects of Anthropogenic Sulfate Aerosol 被引量:1
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作者 钱云 汪宏七 +1 位作者 符淙斌 王自发 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1998年第3期98-110,共13页
On the basis of the emission data of the industrial sulphur dioxide (SO_2) and observed climate fields over East Asia, the distribution of anthropogenic sulfate aerosol(SO_4~2-) with seasonal variation in the troposph... On the basis of the emission data of the industrial sulphur dioxide (SO_2) and observed climate fields over East Asia, the distribution of anthropogenic sulfate aerosol(SO_4~2-) with seasonal variation in the troposphere is simulated and analyzed by a regional sulfur transport model, and the direct radiative effects of SO_4~2- under different weather conditions are also calculated using the discrete ordinate method. The results show that the concentration of SO_4~2- has significant seasonal and spatial variations resulting from the effects of SO_2 emission source and precipitation and wind fields. Both the concentration of SO_2 and its radiative forcing have the largest values in October and the lowest in July. SO_4~2- causes the decrease of the radiation flux absorbed by earth-atmosphere and the cooling of air temperature by scattering more solar radiation back into space. Besides, the radiative and climatic effects of SO_4~2- are related to the types and height and optical thickness, etc., of the clouds. 展开更多
关键词 Sulfate aerosol(SO_4~2-) Radiative effects Seasonal and spatial variations
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Effects of temperature on screening bright-dark the stability of separate spatial soliton pair 被引量:4
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作者 张光勇 刘劲松 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第11期2631-2637,共7页
We investigate theoretically the temperature effects on the evolution and stability of a separate screening brightdark soliton pair formed in a serial non-photovoltaic photorefractive crystal circuit. Our numerical re... We investigate theoretically the temperature effects on the evolution and stability of a separate screening brightdark soliton pair formed in a serial non-photovoltaic photorefractive crystal circuit. Our numerical results show that, for a stable bright-dark soliton pair originally formed in a crystal circuit at given temperatures, when one crystal temperature changes, the soliton supported by the other crystal will evolve into another stable soliton if the temperature change is quite small, whereas it will become unstable and experience larger cycles of compression or break up into beam filaments if the temperature difference is big enough. The dark soliton is more sensitive to the temperature change than the bright one. 展开更多
关键词 nonlinear optics spatial optical solitons photorefractive effects soliton pair
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