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Physical characteristics of high concentrated gas hydrate reservoir in the Shenhu production test area,South China Sea
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作者 Jiapeng JIN Xiujuan WANG +7 位作者 Zhenyu ZHU Pibo SU Lixia LI Qingping LI Yiqun GUO Jin QIAN Zhendong LUAN Jilin ZHOU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期694-709,共16页
High concentrated and heterogeneous distribution of gas hydrates have been identified in the gas hydrate production test region in the Shenhu area,South China Sea.The gas hydrate-bearing sediments with high saturation... High concentrated and heterogeneous distribution of gas hydrates have been identified in the gas hydrate production test region in the Shenhu area,South China Sea.The gas hydrate-bearing sediments with high saturation locate at two ridges of submarine canyon with different thickness and saturations just above the bottom simulating reflection.The crossplots of gamma ray,acoustic impedance(P-impedance)and porosity at four sites show that the sediments can be divided into the upper and lower layers at different depths,indicating different geotechnical reservoir properties.Therefore,the depositional environments and physical properties at two ridges are analyzed and compared to show the different characteristics of hydrate reservoir.High porosity,high P-wave velocity,and coarse grain size indicate better reservoir quality and higher energy depositional environment for gas hydrate at Sites W18 and W19 than those at Sites W11 and W17.Our interpretation is that the base of canyon deposits at Sites W18 and W19 characterized by upward-coarsening units may be turbidity sand layers,thus significantly improving the reservoir quality with increasing gas hydrate saturation.The shelf and slope sliding deposits compose of the fine-grained sediments at Sites W11 and W17.The gas hydrate production test sites were conducted at the ridge of W11 and W17,mainly because of the thicker and larger area of gas hydrate-bearing reservoirs than those at Sites W18 and W19.All the results provide useful insights for assessing reservoir quality in the Shenhu area. 展开更多
关键词 reservoir properties gas hydrate production test region depositional environment South China Sea
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Construction of Land Resource Security System for Core Grain Production Region in Henan Province 被引量:1
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作者 杨建波 卫华鹏 +1 位作者 王莉 邵红旗 《Agricultural Science & Technology》 CAS 2017年第12期2435-2439,共5页
To solve the contradiction between supply and demand of land, the con- struction of land resource security guarantee system is an important part to coordi- nate the economic development and cultivated land protection ... To solve the contradiction between supply and demand of land, the con- struction of land resource security guarantee system is an important part to coordi- nate the economic development and cultivated land protection in the core grain pro- duction region. Based on the deep analysis on the land resources characteristics and problems using the combined method of literature review method with qualita- tive and quantitative analysis, we constructed the land resource security system for different categories according to the land use principles of optimization, intensivism, improvement, and overall planning, and proposed the corresponding supporting mea- sures. The results showed that controlling the new increase, promoting the reclama- tion and improvement of land are the basis for land resource security, clearing the idle, improving the utilization rate of stock are the core of the efficient use of land resources, and establishing a unified urban and rural construction land market is the key to promoting the economical and intensive utilization of land resources, provid- ing scientific basis for the sustainable utilization of land resources in the core grain production regions. 展开更多
关键词 core grain production region Land resources Security system Con-struction
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Optimized Strategy for Layout of Crop Production Areas in Hunan Province
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作者 邓文 杨玉 《Agricultural Science & Technology》 CAS 2014年第11期2049-2052,共4页
The optimized strategy made a comprehensive consideration of resources, technology, market orientation, production scale, industry basis and layout based on the principle of crop security and farmers’ income increasi... The optimized strategy made a comprehensive consideration of resources, technology, market orientation, production scale, industry basis and layout based on the principle of crop security and farmers’ income increasing, and determined the general planning on layout and structure optimization of future crop production ar-eas, with present crop production, market outlook, future industry development, con-cluding crop production characteristics of the 4 crop regions, and proposing function orientation and highlights. 展开更多
关键词 Crop production Regional distribution Optimized strategy Hunan
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Responses of water productivity to irrigation and N supply for hybrid maize seed production in an arid region of Northwest China 被引量:5
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作者 RAN Hui KANG Shaozhong +4 位作者 LI Fusheng DU Taisheng DING Risheng LI Sien TONG Ling 《Journal of Arid Land》 SCIE CSCD 2017年第4期504-514,共11页
Water and nitrogen(N) are generally two of the most important factors in determining the crop productivity. Proper water and N managements are prerequisites for agriculture sustainable development in arid areas. Fie... Water and nitrogen(N) are generally two of the most important factors in determining the crop productivity. Proper water and N managements are prerequisites for agriculture sustainable development in arid areas. Field experiments were conducted to study the responses of water productivity for crop yield(WP_(Y-ET)) and final biomass(WP_(B-ET)) of film-mulched hybrid maize seed production to different irrigation and N treatments in the Hexi Corridor, Northwest China during April to September in 2013 and also during April to September in 2014. Three irrigation levels(70%–65%, 60%–55%, and 50%–45% of the field capacity) combined with three N rates(500, 400, and 300 kg N/hm^2) were tested in 2013. The N treatments were adjusted to 500, 300, and 100 kg N/hm^2 in 2014. Results showed that the responses of WP_(Y-ET) and WP_(B-ET) to different irrigation amounts were different. WP_(Y-ET) was significantly reduced by lowering irrigation amounts while WP_(B-ET) stayed relatively insensitive to irrigation amounts. However, WP_(Y-ET) and WP_(B-ET) behaved consistently when subjected to different N treatments. There was a slight effect of reducing N input from 500 to 300 kg/hm^2 on the WP_(Y-ET) and WP_(B-ET), however, when reducing N input to 100 kg/hm^2, the values of WP_(Y-ET) and WP_(B-ET) were significantly reduced. Water is the primary factor and N is the secondary factor in determining both yield(Y) and final biomass(B). Partial factor productivity from applied N(PFP_N) was the maximum under the higher irrigation level and in lower N rate(100–300 kg N/hm^2) in both years(2013 and 2014). Lowering the irrigation amount significantly reduced evapotranspiration(ET), but ET did not vary with different N rates(100–500 kg N/hm^2). Both Y and B had robust linear relationships with ET, but the correlation between B and ET(R^2=0.8588) was much better than that between Y and ET(R^2=0.6062). When ET increased, WP_(Y-ET) linearly increased and WP_(B-ET) decreased. Taking the indices of Y, B, WP_(Y-ET), WP_(B-ET) and PFP_N into account, a higher irrigation level(70%–65% of the field capacity) and a lower N rate(100–300 kg N/hm^2) are recommended to be a proper irrigation and N application strategy for plastic film-mulched hybrid maize seed production in arid Northwest China. 展开更多
关键词 water use efficiency water stress nitrogen use efficiency evapotranspiration water productivity for yield water productivity for biomass arid region
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如何在Windows NT环境下进行远程访问
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作者 张鸿 王小燕 孙旭映 《干旱气象》 2001年第1期52-54,共3页
The meteorological operation system production database used in the stations at the extension of Lanzhou Regional Meteorological Center (LRMC), is an important part of the second period project setting up items. The s... The meteorological operation system production database used in the stations at the extension of Lanzhou Regional Meteorological Center (LRMC), is an important part of the second period project setting up items. The system includes the database, function module and self-safeguard system. The products of the system can be easily explanted from VMS to UNIX, and their functions can not be affected. 展开更多
关键词 region operational system production database
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Regional Companies of PetroChina Expand Local Oil Products Market Rapidly
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《China Oil & Gas》 CAS 2001年第4期46-47,共2页
关键词 Regional Companies of PetroChina Expand Local Oil Products Market Rapidly
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Nuclear decay database in fission product mass region
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作者 黄小龙 杨东 +4 位作者 葛智刚 王香涵 刘洋阳 金永利 李剑 《Chinese Physics C》 SCIE CAS CSCD 2024年第7期176-180,共5页
Accurate and reliable nuclear decay databases are essential for fundamental and applied nuclear research studies.However,decay data are not usually as accurate as expected and need improvement.Hence,a new Chinese nucl... Accurate and reliable nuclear decay databases are essential for fundamental and applied nuclear research studies.However,decay data are not usually as accurate as expected and need improvement.Hence,a new Chinese nuclear decay database in the fission product mass region(A=66−172)based on several major national evaluated data libraries has been developed under joint efforts in the CNDC working group.A total of 2358 nuclides have been included in this decay database.Two main data formats,namely ENSDF and ENDF,have been adopted.For the total meanβandγenergies,available data from total absorption gamma ray spectroscopy measurements have been adopted.For some nuclides without experimental measurements,theoretically calculated values have been added. 展开更多
关键词 nuclear decay data evaluation database fission product mass region
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A Nonlinear Grey Bernoulli Model with Conformable Fractional-Order Accumulation and Its Application to the Gross Regional Product in the Cheng-Yu Area
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作者 Wenqing WU Xin MA +1 位作者 Bo ZENG Yuanyuan ZHANG 《Journal of Systems Science and Information》 CSCD 2024年第2期245-273,共29页
This study considers a nonlinear grey Bernoulli forecasting model with conformable fractionalorder accumulation,abbreviated as CFNGBM(1,1,λ),to study the gross regional product in the ChengYu area.The new model conta... This study considers a nonlinear grey Bernoulli forecasting model with conformable fractionalorder accumulation,abbreviated as CFNGBM(1,1,λ),to study the gross regional product in the ChengYu area.The new model contains three nonlinear parameters,the power exponentγ,the conformable fractional-orderαand the background valueλ,which increase the adjustability and flexibility of the CFNGBM(1,1,λ)model.Nonlinear parameters are determined by the moth flame optimization algorithm,which minimizes the mean absolute prediction percentage error.The CFNGBM(1,1,λ)model is applied to the gross regional product of 16 cities in the Cheng-Yu area,which are Chongqing,Chengdu,Mianyang,Leshan,Zigong,Deyang,Meishan,Luzhou,Suining,Neijiang,Nanchong,Guang’an,Yibin,Ya’an,Dazhou and Ziyang.With data from 2013 to 2021,several grey models are established and results show that the new model has higher accuracy in most cases. 展开更多
关键词 nonlinear grey Bernoulli model conformable fractional-order operator moth flame optimization algorithm gross regional product the Cheng-Yu area
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Simple Fourth-Degree Cubature Formulae with Few Nodes over General Product Regions
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作者 Ran Yu Zhaoliang Meng Zhongxuan Luo 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2014年第2期179-192,共14页
A simple method is proposed for constructing fourth-degree cubature formulae over general product regions with no symmetric assumptions. The cubatureformulae that are constructed contain at most n2 + 7n + 3 nodes and ... A simple method is proposed for constructing fourth-degree cubature formulae over general product regions with no symmetric assumptions. The cubatureformulae that are constructed contain at most n2 + 7n + 3 nodes and they are likelythe first kind of fourth-degree cubature formulae with roughly n2 nodes for nonsymmetric integrations. Moreover, two special cases are given to reduce the numberof nodes further. A theoretical upper bound for minimal number of cubature nodesis also obtained. 展开更多
关键词 Fourth-degree cubature formula cubature formula product region non-symmetric region numerical integration
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The Largest Copper, Aluminum Wire and Cable Production Enterprise in the Northwestern Region Lands in Qinghai
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《China Nonferrous Metals Monthly》 2017年第7期7-8,共2页
The largest wire and cable production enterprise in the northwestern region-Qinghai Xingming Electric Power Material Co.,Ltd.has been officially put into production,meaning that Qinghai will be able to selfproduce med... The largest wire and cable production enterprise in the northwestern region-Qinghai Xingming Electric Power Material Co.,Ltd.has been officially put into production,meaning that Qinghai will be able to selfproduce medium and high voltage or even EHV crosslinked power cables and develop and produce differentiated new products such as high-altitude cold-resistant photovoltaic 展开更多
关键词 in is The Largest Copper Aluminum Wire and Cable production Enterprise in the Northwestern Region Lands in Qinghai been high
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Emerging Geography of Creativity and Labor Productivity Effects in China 被引量:4
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作者 Wentao Yu Jin Hong +2 位作者 Yanrui Wu Dingtao Zhao Jing Qiu 《China & World Economy》 SCIE 2013年第5期78-99,共22页
The paper presents an alternative approach to explain why regional productivity is different across regions by utilizing the creative class approach in China. First, we analyze the extent of spatial agglomeration of t... The paper presents an alternative approach to explain why regional productivity is different across regions by utilizing the creative class approach in China. First, we analyze the extent of spatial agglomeration of the creative class across regions in China. Second, we develop a model with spatial externalities to investigate how the concentration of the creative class can promote regional productivity. Our analysis confirms the importance of spatial agglomeration of the creative class in stimulating regional productivity. The results also imply that regional productivity is greater in markets with higher levels of innovation, capital stock, manufacturing and urbanization. In light of the results of our analysis, we discuss a number of policy implications. 展开更多
关键词 China creative class agglomeration CREATIVITY regional labor productivity spatial externality
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Current status of greenhouse gas emissions from aquaculture in China 被引量:2
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作者 Congjun Xu Guohuan Su +5 位作者 Kangshun Zhao Xiaoqi Xu Ziqi Li Qiang Hu Ying Xue Jun Xu 《Water Biology and Security》 2022年第3期10-17,共8页
Aquaculture and mariculture are becoming an increasingly important source of food supply in many countries and regions.However,with the expansion of aquaculture and mariculture comes increasing emissions of greenhouse... Aquaculture and mariculture are becoming an increasingly important source of food supply in many countries and regions.However,with the expansion of aquaculture and mariculture comes increasing emissions of greenhouse gases(GHG)which contribute to global warming and climate change.China leads the world in aquaculture and mariculture production,but there are no studies that systematically assess China's overall carbon footprint from these industries.This study quantified GHG emissions from aquaculture and mariculture by four source phases(feed,energy use,nitrous oxide and fertilizers),and then analyzed the carbon footprint of each of these phases for GHG production of nine major species groups over the past ten years to show the spatial distribution of GHG emissions from aquaculture and mariculture in China.Our results showed that the production of feed materials contributed most to the GHG emissions and found that crop energy use,crop land use changes(LUC),fertilizer production,crop nitrous oxide production and rice methane production were the main sources of feed emissions.The total GHG emissions of the nine species groups were 112 Mt(10^(9) kg)CO_(2)e,the nine species accounting for approximately 86%of aquaculture and mariculture production.GHG emissions of cyprinids had the highest contribution at 47%.Spatial analysis based on our study showed Guangdong,Hubei,Jiangsu and Shandong had the highest GHG emissions of all the provinces in this study,and they accounted for approximately 46%of all emissions.The regional Gross Domestic Product(GDP)was significantly positively correlated with GHG emissions in every province,with a correlation coefficient higher than 0.6.Our results showed for the first time the relationship between the relative production by species composition and spatial distribution of GHG emissions from aquaculture and mariculture in China.Our findings provide the scientific basis for reduction of GHG emissions within a broader context of expanding aquaculture in the future. 展开更多
关键词 Greenhouse gas emissions AQUACULTURE MARICULTURE Species group FEED Carbon footprint Regional gross domestic product
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Evaluation of the efficiency of fixed assets of economic sectors based onindex analysis
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作者 Alisa Ableeva Guzel Salimova +2 位作者 Tatiana Lubova Almira Farrahetdinova Raisa Siraeva 《Journal of Management Analytics》 EI 2022年第3期369-382,共14页
This article is devoted to the study of the system of indicators characterizing thevolume, structure and efficiency of the functioning of fixed assets of theproduction and non-production areas of the region based on t... This article is devoted to the study of the system of indicators characterizing thevolume, structure and efficiency of the functioning of fixed assets of theproduction and non-production areas of the region based on the index analysis.Through factorial index analysis, models of the relationship between the grossregional product, the cost of fixed assets and capital productivity (capitalintensity) of industries producing goods and providing services were obtained,to identify reserves for increasing of the analyzed indicators. The obtainedresults indicate a trend towards significant decrease in capital productivity inthe production sector, which should become the basis for making managerialdecisions at the regional level to attract investment. They can be used in thepractice of macroeconomic analysis and forecasting, for detailing the factors fordetermining the potential of economic sectors, the efficiency of using fixedassets, and attracting investments. 展开更多
关键词 gross regional product factor index analysis capital productivity capital intensity
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PRODUCTIVITY AND WATER UTILITY FOR MAIN CROPS IN LOESSAL HILL.REGION, SOUTHERN NINGXIA
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作者 山崙 孙纪斌 《Chinese Science Bulletin》 SCIE EI CAS 1986年第16期1151-1152,共2页
The loessal hill region in southern Ningxia is a semiarid and severe eroded area with developed agriculture and animal husbandry. It has long been an argument whether there might be more potentiality of farming and wh... The loessal hill region in southern Ningxia is a semiarid and severe eroded area with developed agriculture and animal husbandry. It has long been an argument whether there might be more potentiality of farming and whether food production can be sustained at a level of local sufficiency. 展开更多
关键词 SOUTHERN NINGXIA PRODUCTIVITY AND WATER UTILITY FOR MAIN CROPS IN LOESSAL HILL.REGION
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