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区域间性:律师参与“一带一路”公共法律服务论纲
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作者 刘澍 丁鑫 《商丘师范学院学报》 CAS 2018年第10期82-87,共6页
律师参与"一带一路"公共法律服务的性质是由服务需求市场之区域间性决定的。"一带一路"打造的是沿途国家、地区、民众的利益共同体和丝路精神,其基本的理论前提是区域间性,即平等、合作、和平、互利原则。而律师法... 律师参与"一带一路"公共法律服务的性质是由服务需求市场之区域间性决定的。"一带一路"打造的是沿途国家、地区、民众的利益共同体和丝路精神,其基本的理论前提是区域间性,即平等、合作、和平、互利原则。而律师法律服务的本质是助推法律正义的实现,这决定了律师参与"一带一路"公共法律服务的通力协作者角色担当。 展开更多
关键词 “一带一路” 公共法律服务 区域间性 伙伴关系
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Intermediate formation enabled regioselective access to amide in the Pd-catalyzed reductive aminocarbonylation of olefin with nitroarene 被引量:2
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作者 Li Yang Lijun Shi +1 位作者 Chungu Xia Fuwei Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第7期1152-1160,共9页
An efficient route for the palladium-catalyzed reductive aminocarbonylation of olefins with nitroarenes was developed using carbon monoxide(CO)as both reductant and carbonyl source,which enables facile access to amide... An efficient route for the palladium-catalyzed reductive aminocarbonylation of olefins with nitroarenes was developed using carbon monoxide(CO)as both reductant and carbonyl source,which enables facile access to amides with excellent regioselectivity and broad substrate scope.It is found that the counter anions of the Pd catalyst precursors significantly affect the reaction chemoselectivity and amide regioselectivity.Branched amides were mainly obtained with K2PdCl4 as the metal catalyst,and phosphine ligands had no influence on the regioselectivity but affected the catalytic reactivity.However,phosphine ligands had significant effects on aminocarbonylation regioselectivity when Pd(CH3CN)4(OTf)2 was used;monodentate phosphines tended to form branched amides,and bidentate phosphines mainly formed linear amides.Trapping experiments,primary kinetic studies,and control reactions with all possible N-species reduced from nitroarene indicated that the catalytic synthesis of branched and linear amides produced nitrene(further converted to enamide)and aniline,respectively,different from the previous ligand-controlled regioselective synthesis of amides via the aminocarbonylation of olefins with amines.Furthermore,the proposed synthesis route could be applied in the synthesis of gram-scale propanil under mild conditions. 展开更多
关键词 NITROARENES AMIDES N-intermediate AMINOCARBONYLATION Regioselectivity
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Spatial Correlation and Ecological Characteristics Analysis of Man-agement Area for Biodiversity Conservation and Relevant Regionalization 被引量:5
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作者 WANG Wenjie ZHENG Hua +5 位作者 XU Chao JIANG Weiguo DU Yunhui WANG Wei ZHANG Zhe LIU Xiaofu 《Chinese Geographical Science》 SCIE CSCD 2014年第1期71-82,共12页
Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in... Formulation of different ecological zone plans according to the corresponding protection targets and the necessity of proper conservation policy is one of the measures to achieve the goal of ecological conservation in China.In order to clarify the interrelation among key ecological zone plans,this paper carried out the research on spatial relation of priority areas of biodiversity conservation and three key ecological areas(key ecological function areas,key regions of ecological service function,national nature reserves)and the research on ecological conditions,based on multi-scale ecological spatial theme information,which incorporates elements like ecological quality and type,and by the aid of spatial information analysis and GIS modeling.The results showed a contrastively fine spatial consistency with 68.8%of priority areas of biodiversity conservation overlapping with three key ecological areas.Although the environment in priority areas of biodiversity conservation were in good conditions,protection pressure is also increasing,powerful supervision and protection should not be ignored.The environmental conditions in the overlapping areas,as a whole,were superior to those in the non-overlapping areas.Since two areas have different characteristics,targeted protection measures should be formulated based on this difference,which will be very important for biodiversity conservation in priority areas of biodiversity conservation. 展开更多
关键词 biodiversity conservation ecological regionalization ecological pressure ecological service spatial correlation analysis
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对我国政府间管制所引发财政问题的思考 被引量:3
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作者 薛钢 《涉外税务》 北大核心 2002年第8期17-20,共4页
随着经济体制改革的深入,政府间管制的情况也日益增多,而在我国这些政府间管制已经对财政体制产生了较大的冲击,使得原有的管制目标难以实现,并伴随产生新的财政问题和制度变异。应借鉴西方国家的政府间管制理论和经验,对我国的财政体... 随着经济体制改革的深入,政府间管制的情况也日益增多,而在我国这些政府间管制已经对财政体制产生了较大的冲击,使得原有的管制目标难以实现,并伴随产生新的财政问题和制度变异。应借鉴西方国家的政府间管制理论和经验,对我国的财政体制、行政体制、法律和民主体制等方面进行完善,减少政府间管制产生的财政风险。 展开更多
关键词 政府间管制 区域间外部 财政风险 税收竞争
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Spatial expansion and potential of construction land use in the Yangtze River Delta 被引量:6
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作者 王振波 方创琳 张晓瑞 《Journal of Geographical Sciences》 SCIE CSCD 2015年第7期851-864,共14页
Based on remote sensing data of the Yangtze River Delta(YRD) in the years of 1991, 2001 and 2008, the paper built an index system of land use potential restraint factors in YRD, according to geological condition, terr... Based on remote sensing data of the Yangtze River Delta(YRD) in the years of 1991, 2001 and 2008, the paper built an index system of land use potential restraint factors in YRD, according to geological condition, terrain condition, water area, natural reserve area and basic farmland, and evaluated construction land potential based on the platform of GIS spatial analysis model. The results showed that:(1) the construction land increased rapidly since 1991 and reached 24,951.21 km2 in 2008, or 21.27% of the total area. Among all the cities in the YRD, Shanghai took the greatest percentage, followed by Jiangsu and Zhejiang. Spatially, areas where government departments are located became the growth center of construction land. Prefecture-level cities were the fastest growth region and the changing trend showed circle layered characteristics and significant increase with Shanghai and Suzhou as the core.(2) The higher the quality of construction land potentials(CLP), the smaller the number of CLP units. High sensitive area accounted for the largest percentage(40.14%) among all types of constraint regions and this was followed by medium sensitive region(31.53%) of the whole region.(3) The comprehensive CLP in the YRD was 24,989.65 km2, or 21.76% of the total YRD. The land use potential showed spatial distribution imbalance. CLP of Zhejiang was obviously larger than that of Jiangsu. CLP was insufficient in regional central city. Moreover, CLP in the YRD formed a circle layered spatial pattern that increasingly expanded centered in prefecture-level cities. Low potential area expanded from north to south. High potential area was mainly located in south YRD. Areas with zero potential in the YRD formed a northwest-southeast "Y-shaped" spatial pattern in north Hangzhou Bay.(4) CLP per capita in YRD was 0.045 ha/person and also unevenly distributed. Some 25.57% of the study units at county level nearly had no construction land and 8.24% of the units had CLP per capita below the national average level. CLP per capita in less than 25% of the county-level units was larger than the YRD average level, which were mainly located in Zhejiang. Therefore, research on the construction potential area in YRD was favorable for analysis of the development status and potential space of this region under the background of rapid urbanization and industrialization. 展开更多
关键词 Yangtze River Delta construction land use potential zoning spatial expansion
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Uncertainty in crossing time of 2 °C warming threshold over China 被引量:16
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作者 Xiaolong Chen Tianjun Zhou 《Science Bulletin》 SCIE EI CAS CSCD 2016年第18期1451-1459,共9页
The 2 ℃ warming target has been used widely in global and regional climate change research. Previous studies have shown large uncertainties in the time when surface air temperature (SAT) change over China will reac... The 2 ℃ warming target has been used widely in global and regional climate change research. Previous studies have shown large uncertainties in the time when surface air temperature (SAT) change over China will reach 2℃ rela- tive to the pre-industrial era. To understand the uncertainties, we analyzed the projected SAT in the twenty-first century using 40 state-of-the-art climate models under two Repre- sentative Concentration Pathways (RCP4.5 and RCPS.5) from the Coupled Model Intercomparison Project Phase 5. The 2℃ threshold-crossing time (TCT) of SAT averaged across China was around 2033 and 2029 for RCP4.5 and RCP8.5, respectively. Considering a 4-1o- range of inter- model SAT change, the upper and lower bounds of the 2 ℃ TCT could differ by about 25 years or even more. Uncer- tainty in the projected SAT and the warming rate around the TCT are the two main factors responsible for the TCT uncertainty. The former is determined by the climate sensi- tivity represented by the global mean surface temperature response. About 45 % of the intermodel variance of the projected 2 ~C TCT for averaged SAT over China can be explained by climate sensitivity across the models, which is contributed mainly by central and southern China. In a cli- mate more sensitive to CO2 forcing, stronger greenhouse effect, less stratus cloud over the East Asian monsoon region, and less snow cover on the Tibetan Plateau result in increased downward longwave radiation, increased shortwave radia- tion, and decreased shortwave radiation reflected by the surface, respectively, all of which may advance the TCT. 展开更多
关键词 2 °C threshold Projection uncertainty China region CMIP5 Climate sensitivity
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The Generic Annular Bucket Histogram for Estimating the Selectivity of Spatial Selection and Spatial Join
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作者 Changxiu Cheng Chenghu Zhou Rongguo Chen 《Geo-Spatial Information Science》 2011年第4期262-273,共12页
Selectivity estimation is crucial for query optimizers choosing an optimal spatial execution plan in a spatial database management system.This paper presents an Annular Bucket spatial histogram(AB histogram)that can e... Selectivity estimation is crucial for query optimizers choosing an optimal spatial execution plan in a spatial database management system.This paper presents an Annular Bucket spatial histogram(AB histogram)that can estimate the selectivity in finer spatial selection and spatial join operations even when the spatial query has more operators or more joins.The AB histogram is represented as a set of bucket-range,bucket-count value pairs.The bucket-range often covers an annular region like a sin-gle-cell-sized photo frame.The bucket-count is the number of objects whose Minimum Bounding Rectangles(MBRs)fall between outer rectangle and inner rectangle of the bucket-range.Assuming that all MBRs in each a bucket distribute evenly,for every buck-et,we can obtain serial probabilities that satisfy a certain spatial selection or join conditions from the operations' semantics and the spatial relations between every bucket-range and query ranges.Thus,according to some probability theories,spatial selection or join selectivity can be estimated by the every bucket-count and its probabilities.This paper also shows a way to generate an updated AB histogram from an original AB histogram and those probabilities.Our tests show that the AB histogram not only supports the selectivity estimation of spatial selection or spatial join with "disjoint","intersect","within","contains",and "overlap" operators but also provides an approach to generate a reliable updated histogram whose spatial distribution is close to the distribution of ac-tual query result. 展开更多
关键词 selectivity estimation AB histogram annular bucket spatial selection spatial join
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