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Production of Railwayscape in urban environment:Analysing railway heritage tourism potential in Siliguri City,India
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作者 Iman BANERJEE 《Regional Sustainability》 2023年第1期1-12,共12页
For a long time,it has been argued that the theories and practices devoted to urban planning and management should conform to the fundamental role of planning policies in the production of urban space,but not merely t... For a long time,it has been argued that the theories and practices devoted to urban planning and management should conform to the fundamental role of planning policies in the production of urban space,but not merely the spatial distribution of the produced services.Towards this wider connotation,this study introduces the notion of Railwayscape,grounded on the theory of‘The Production of Space’,to examine the role of railway station districts as catalysts of urban development through the social production of urban space.The present research sets out to establish the notion of Railwayscape and apply it in a railway heritage,i.e.,the Darjeeling Himalayan Railway(DHR)and its point of inception,Siliguri City,India.Accordingly,a criteria-based evaluation of four railway station districts(New Jalpaiguri,Siliguri Town,Siliguri Junction,and Sukna)in Siliguri and its surroundings was performed.The information regarding the selected four railway station districts is obtained through field observation and key informant consultation,supplemented by published literature and remote sensing data.This evaluation is succeeded by the strengths,weaknesses,opportunities and threats(SWOT)analysis accentuating the potential strengths,weaknesses,opportunities and threats associated with the selected four railway station districts and their prospects to become the potential Railwayscape.The results of this research show that there is no railway station district in Siliguri that can fully meet the demands of the locals and tourists,therefore,relfecting a lack of awareness of the historical values of these districts.The results also indicate that there are significant differences in the relative potentials of railway station districts to become the Railwayscape in urban environment.The outcomes of this research,therefore,are expected to encourage policy-making insitutions and practitioners to realise the‘place value’of some railway station districts and their potentials to yield better economic,social and structural virtue for a wide range of actors. 展开更多
关键词 Railwayscape Darjeeling Himalayan Railway(DHR) The production of space Siliguri city Railway heritage tourism potential
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Research on the Dynamic Climatic Production Potential of Middle-season Rice in Jiangxi Province 被引量:2
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作者 李忠辉 胡培成 黄晚华 《Meteorological and Environmental Research》 CAS 2010年第3期50-52,63,共4页
According to the meteorological data from Meteorological Station during 1961-2007 in Jiangxi Province,using the calculation method of production potential of climate recommended by Food and Agriculture Organization(FA... According to the meteorological data from Meteorological Station during 1961-2007 in Jiangxi Province,using the calculation method of production potential of climate recommended by Food and Agriculture Organization(FAO),the variation trends of climatic potential productivity of mid-season rice during this period were analyzed.The results indicated a trend of yearly decline in the variation of photosynthetic and light-temperature potential productivity in Jiangxi.The changes of climatic production potential fluctuated widely.The main reasons for the above-mentioned changes in recent years included more serious air pollution,resulting in less light and decline in photosynthetic potential productivity.An increase in extreme high-temperature days inhibited the growth of mid-season rice.The uneven distribution of precipitation resulted in the volatility of climatic production potential.To ensure high and stable yield,some counter-measures should be taken,including increasing weather modification input,building water conservancy facilities,enhancing the accuracy of weather forecasts and strengthening the research on climate changes.All the methods could solve those problems so as to ensure an improvement in rice production capacity to address climate change. 展开更多
关键词 Middle-season rice Climatic potential productivity DYNAMIC China
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Analysis of Natural Condition,Present Situation and Potential of Rice Production Development in Angola 被引量:2
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作者 杨前进 《Agricultural Science & Technology》 CAS 2011年第12期1983-1984,F0003,共3页
[Objective] The aim was to make analysis on natural condition,present situation,and potential of rice production development in Angola.[Method] Conclusion and analysis of rice development in Angola were conducted from... [Objective] The aim was to make analysis on natural condition,present situation,and potential of rice production development in Angola.[Method] Conclusion and analysis of rice development in Angola were conducted from natural condition,production status,present problem and development potential.[Result] In Angola,about 30 million hectares agricultural lands enjoy fresh water,temperature,and light resources which are requirement for rice development.Presently,however,some disadvantages have harassed the nation,such as outdated production mode and technology,small cultivated area and low level of per unit yield.In addition,about 98% of consumed rice was imported from other countries.The government has attached high importance to food production,and rice production was a priority of national investment.Per unit rice yield would achieve 7 500 kg/hm2 if Angola introduces hybrid rice species and high-yield cultivation techniques from China.[Conclusion] The research provided technical reference for enterprises or individuals ready to invest in rice development in Angola. 展开更多
关键词 Rice in Angola production status Development potential
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Climate Characteristics in Three Gorges Reservoir Area after Water Storage and Its Impact on the Production Potential
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作者 钟海玲 高荣 杨霞 《Meteorological and Environmental Research》 CAS 2010年第2期53-56,共4页
Based on the meteorological data from 33 stations of Three Gorges Reservoir from 1960 to 2008,climate yield of rice,corn and winter wheat and the changes of climatic potential productivity after water storage in Three... Based on the meteorological data from 33 stations of Three Gorges Reservoir from 1960 to 2008,climate yield of rice,corn and winter wheat and the changes of climatic potential productivity after water storage in Three Gorges Reservoir were calculated by the dynamic statistic model of crop growth.The results showed that the temperature in Three Gorges Reservoir was fluctuant decreased before late 1980s,and warmed rapidly after the late 1980s.The precipitation had little change before the late 1990s and had a slight decrease after the late 1990s.Sunshine hours were more in 1960s and 1970s,and then it changed little after 1980s.After water storage,the temperature increased in Three Gorges Reservoir as a whole.The precipitation decreased in the south of Three Gorges Reservoir,while it increased in the northwest of Three Gorges Reservoir.The sunshine hours were reduced except that in the vicinity of Dianjiang.After water storage,climatic potential productivity of rice decreased in the northwest and the northeast,while it increased in the south of Three Gorges Reservoir.The climatic potential productivity of corn decreased in the northeast and the southwest,but increased in the rest of Three Gorges Reservoir.The climatic potential productivity of winter wheat increased almost in total. 展开更多
关键词 Three Gorges Reservoir area Water storage Climatic potential productivity CHANGE China
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Production and trade trend of oils and oilseeds in BRICS countries
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作者 ZHANG Hong 《中国油脂》 CAS CSCD 北大核心 2024年第8期1-10,共10页
In order to promote agricultural production and trade cooperation among BRICS countries,and ensure the security and stability of the oils and oilseeds industrial and supply chains in China and the world,the production... In order to promote agricultural production and trade cooperation among BRICS countries,and ensure the security and stability of the oils and oilseeds industrial and supply chains in China and the world,the production,consumption,trade trend,and cooperation potential of oils and oilseeds in BRICS countries were expounded,and relevant policy recommendations were put forward.Most of the BRICS countries are major agricultural producers,and they are also important agricultural product consumption markets in the world.In 2023/2024,the production and consumption of oilseeds in BRICS countries account for nearly half of the world's total;the production of vegetable oils exceeds a quarter of the world's total,and the consumption of vegetable oils accounts for 40%of the world's total.In 2023/2024,the import and export volume of oilseeds exceeds half of the world's total;vegetable oil imports account for 40%of the world's total,and exports account for about one tenth of the world's total.China's imports of oilseeds and oils from BRICS countries account for 68%and 29%of its global imports in 2023,respectively.BRICS countries are rich in agricultural land resources,have great potential for oils and oilseeds production,obvious complementary advantages in trade structure,and huge space for future cooperation.It is suggested that Brazil should be included in the"Belt and Road"co-construction category to promote the continuous deepening of agricultural cooperation between China and Brazil.It is suggested to explore regional agricultural trade agreements among BRICS countries,promote currency settlement and exchange among BRICS countries,and enhance the facilitation and stability of BRICS trade.It is suggested that China should increase its investment in BRICS countries and export advanced technology and management experience to benefit local agricultural development and achieve a mutually beneficial and win-win situation. 展开更多
关键词 BRICS countries oils and oilseeds production and consumption trade trend agricultural potential
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Inconsistent increasing of climate potential productivity resulting from global warming and land use transitions in the Dongting Lake Basin,from 2000 to 2020 被引量:1
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作者 WANG Ji-ren ZHENG Jian +2 位作者 SU Jian ZHENG Bo-hong SUN Zhao-qian 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1954-1967,共14页
In the face of global warming and increasing impervious surfaces,quantifying the change of climate potential productivity(CPP)is of great significance for the food production planning.Targeting the Dongting Lake Basin... In the face of global warming and increasing impervious surfaces,quantifying the change of climate potential productivity(CPP)is of great significance for the food production planning.Targeting the Dongting Lake Basin,which is a key area for food production in China,this paper uses meteorological data,as well as Climate Change Initiative Land Cover,and Shuttle Radar Topography Mission digital elevation model to investigate the CPP and its changes from 2000 to 2020.The suitability of land for cultivation(SLC),and the land use/land cover change(LUCC)are also considered.The results showed that the CPP varied from 9,825 to 20,895 kg ha^(-1).Even though the newly added impervious surfaces indirectly resulted in the decrease of CPP by of 9.81×10~8 kg,overall,the CPP increased at an average rate of 83.7 kg ha^(-1)a^(-1).Global warming is the strongest driver behind CPP increase,and CPP has played an important role in the conversions between cultivated land and other land types.The structure of land types tends to be optimized against this challenge. 展开更多
关键词 Land cultivation Land use/land cover change Climate potential productivity Global warming Dongting Lake Basin
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Analysis of the Identification of Local Agriculture Products in the Municipality of Aileu, Manufahi, and Ainaro That Have Potential for Export and Attract Foreign Investments in Agricultural Sector
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作者 Vicente De Paulo Correia José Nelson Salsinha +4 位作者 Oscar Da Silva Carlos Da Conceição De Deus Mateus De Jesus Gomes Graciano Soares Gomes Decio R. Sarmento 《Agricultural Sciences》 CAS 2023年第2期145-153,共9页
The objective of this study is to identify and collect information on local agriculture products and identify local potential agriculture and livestock that can attract foreign investments. Used Stratified Random Samp... The objective of this study is to identify and collect information on local agriculture products and identify local potential agriculture and livestock that can attract foreign investments. Used Stratified Random Sampling and data was collected from both primary and secondary data (both quantitative and qualitative data. The data analyzed used qualitative and quantitative analysis. The supply chain analysis was carried out to develop a description of the value chain to identify potential high-value market areas and current and potential products in the domestic and export markets. The results of the study revealed that most farmers in the research location grow different types of crops and livestock. In particular for Aileu and Ainaro where most of the areas are up-land, therefore, horticulture crops (mustard, cabbage, carrots, and tomato) and coffee are dominated in these areas. For Manufahi, some parts are lowland areas, where most crops grown are maize, cassava, and paddy rice. The study reveals that local potential agriculture products and livestock in the municipalities of Aileu, Ainaro, and Manufahi are vegetable, coffee, maize, and paddy rice, banana, shallot, tangerine, cabbage, carrot, cattle, mung-bean, and banana. To accelerate economic growth, in these municipalities, there is a need to modernize agricultural production, requiring markets for both inputs supply and for the sale of output products. Opportunities to increase the productivity of these products are feasible and this can be done through the use of high-variety seeds and better farm management, and the government and private sector can play an important role in improving productivity as this will have a further implication in improving food security. 展开更多
关键词 potential product INVESTMENT Agriculture LIVESTOCK Market
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China’s Potential of Grain Production Due to Changes in Agricultural Land Utilization in Recent Years 被引量:19
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作者 XIN Liangjie LI Xiubin +1 位作者 ZHU Huiyi TAN Minghong 《Chinese Geographical Science》 SCIE CSCD 2009年第2期97-103,共7页
The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from t... The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from the land utilization perspective, involving changes in grain production per unit area, multi-cropping index, and adjustment of agricultural structure. Compared with the record values, different research methodologies are used to analyze the po- tential of above three components. The results indicate that grain production potential of 65.68×109kg was unexploited in 2006, in which 45.8×109kg came from the restructuring in agriculture. So we can infer that the reduction of grain production in China could be primarily attributed to agricultural restructuring in recent years. So the productive poten- tial can be fully restored by increasing agricultural investment, or recovering agricultural structure in favorable condi- tions. So we can say that China’s current condition of food security is good. 展开更多
关键词 grain production potential of grain production agricultural land utilization changes multi-cropping index reduction of grain product food security
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Impact of Climate Variation on the Exploitation Degree of Production Potential of Winter Wheat in Tianshui
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作者 胡利平 张华兰 +2 位作者 安晶 刘晓强 杭波 《Meteorological and Environmental Research》 CAS 2010年第3期45-49,111,共6页
The productivity exploitation degree,suitable exploitation degree and exploitable exploitation degree of production potential of winter wheat in three climate zones of Tianshui were calculated.The impacts of climate c... The productivity exploitation degree,suitable exploitation degree and exploitable exploitation degree of production potential of winter wheat in three climate zones of Tianshui were calculated.The impacts of climate changes on it were analyzed.The results showed the exploitation degree of production potential of winter wheat was still low in the north of Wei River,the valley of Wei River and the area of Guan Mountain in Tianshui,being 49.9%-60.0%.Both the suitable exploitation degree and exploitable exploitation degree of production potential of winter wheat were comparatively high,being 73.6%-78.7% and 18.7%-23.8% respectively.The sequencing was the north of Wei River>the valley of Wei River>the area of Guan Mountain.In the long run,it was of great potential to be excavated.The average temperature,sunshine hours for growth season of winter wheat had negative effects on exploitation degree,suitable exploitation degree and exploitable degree of production potential of winter wheat.The precipitation had the positive effect.And the temperature in the entire growth period,temperature in autumn,the sunshine in winter had remarkable negative effects on the exploitation degree of the production potential in Tianshui and the north of Wei River.The precipitation in the entire growth period,the precipitation in autumn had remarkable positive effects in Tianshui and each climate zones.And some moderate development countermeasures of regional production potential were proposed. 展开更多
关键词 Tianshui area Climatic change production potential Development level Influence factor China
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The coalbed methane production potential method for optimization of wells location selection 被引量:11
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作者 Feng-Ke DOU Yong-Shang KANG +2 位作者 Shao-Feng QIN De-Lei MAO Jun HAN 《Journal of Coal Science & Engineering(China)》 2013年第2期210-218,共9页
A gas production potential method for optimization of gas wellsite locations selection is proposed in terms of the coalbed gas resources volume and the recoverability. The method uses the actual data about reservoirs ... A gas production potential method for optimization of gas wellsite locations selection is proposed in terms of the coalbed gas resources volume and the recoverability. The method uses the actual data about reservoirs in a coalbed gas field in central China to optimize wellsite locations in the studied area in combination with the dynamic data about actual production in the coalbed gas field, selects a favorable subarea for gas wells deployment. The method is established based on the basic properties of coal reservoirs, in combination with the coalbed thickness and the gas content to make an analysis of the gas storage potential of a coal reservoir, as well as resources volume and the permeability of a coal reservoir. This method can be popularized for optimization of wellsite locations in other methane gas development areas or blocks. 展开更多
关键词 coalbed methane gas potential gas production potential method optimization of wellsite locations
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Simulation of Potential Production and Optimum Population Quantitative Indices for the Second Hybrid Rice 被引量:1
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作者 YAN Li-Jiao YAO Zhong ZHENG Zhi-ming LI Hua-bin 《Agricultural Sciences in China》 CAS CSCD 2006年第7期498-505,共8页
The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, ... The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-~. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 x 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03×10^6ha, 3.99×10^6ha, 119.2, 8.59, 5-6, and 0.64, respectively. 展开更多
关键词 SIMULATION MODEL potential production optimum population quantitative indices second hybrid rice
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Evaluation of the Land Production Potential in the Context of Returning Farmland to Forest in Karst Region:A Case Study of Guizhou Province 被引量:2
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作者 Shuang YU Guang LI Ruiping RAN 《Asian Agricultural Research》 2013年第1期21-26,共6页
In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test ... In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test on the actual production capacity of land and the forecasted production capacity of land in 2007 and 2008, and then conduct comprehensive forecast of the land production potential in Guizhou Province in 2020. On this basis, considering the nutritional standards needed by three kinds of life type (dressing warmly and eating one's fill, well-off life, relatively affluent life), we evaluate the land production potential in Guizhou Province under the project of returning farmland to forest. Based on the evaluation results, we put forth the relevant recommendations for achieving sustainable land use in the context of returning farmland to forest in Guizhou Province. 展开更多
关键词 KARST region Project of RETURNING FARMLAND to fore
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Economic Potential of Compost Amendment as an Alternative to Irrigation in Maine Potato Production Systems
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作者 John M. Halloran Robert P. Larkin +2 位作者 Sherri L. DeFauw O. Modesto Olanya Zhongqi He 《American Journal of Plant Sciences》 2013年第2期238-245,共8页
Potato productivity in the northeastern US has been relatively constant for over 50 years, raising questions about what factors are limiting productivity. Research was initiated in 2004 to identify key constraints to ... Potato productivity in the northeastern US has been relatively constant for over 50 years, raising questions about what factors are limiting productivity. Research was initiated in 2004 to identify key constraints to potato productivity by evaluating Status Quo (SQ), Soil Conserving (SC), and Soil Improving (SI) cropping systems under both rainfed and irrigated management, and it was found that addition of compost or irrigation substantially increased yield. In this study, we employed partial budgeting to determine cost differences and their impact on net revenue for these cropping systems. Differences in systems were primarily associated with rotation length, tillage operations, compost and application expenses, and water management practices. When compost (as composted dairy manure) was annually applied at 19 Mg haf-1 and evaluated over the entire 3-year crop rotation cycle, the compost-amended rainfed SI system was more expensive to maintain than the irrigated SC system if compost cost exceeded $3.63 Mg-1. Average marketable yields were used to calculate gross and net revenue for each system. Because average potato yield for the irrigated SQ system (28.4 Mg·ha-1) equaled that in the rainfed SI system (28.3 Mg·ha-1), we were able to compare cost of irrigation versus compost for achieving comparable yield. The compost-amended SI system under rainfed management generated more net revenue from the potato crop than the irrigated SQ system when compost costs were less than $7.42 Mg-1. When compared to the commonly used rainfed SQ system, rainfed SI achieved higher net revenue as long as compost cost was less than $22.95 Mg-1. The rainfed SI system achieved higher net revenue than the irrigated SC system when compost cost was $9.43 Mg-1or less, but generated greater net revenue than the rainfed SC system regardless of compost costs, due to substantially higher yields associated with compost amendment. This investigation demonstrates that compost is a potentially viable substitute to irrigation for potato in the northeastern US;however, such potential is highly dependent on suitable compost sources and application costs. 展开更多
关键词 COMPOST Cropping SYSTEMS ECONOMIC potential IRRIGATION Partial BUDGETING Potato production Water Stress Yield
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Potentials and Constraints of Small-Scale Livestock Productions in Cambodia
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作者 Siek Darith Shiwei Xu +4 位作者 Wen Yu Ahmed Abdul-Gafar Sa Kennvidy Ou Ratanak Eric Mukeba Mbala 《World Journal of Engineering and Technology》 2017年第2期15-22,共8页
Livestock husbandry plays a very important role in rural areas of Cambodia. Farmers mostly have complained about the declining revenue from livestock production which supports their livelihood. Therefore, the study ai... Livestock husbandry plays a very important role in rural areas of Cambodia. Farmers mostly have complained about the declining revenue from livestock production which supports their livelihood. Therefore, the study aimed at investigating the potentials and constraints of smallholder livestock productions in Battambang province. Primary and secondary data were collected to meet the objectives. Data were collected interviewing 204 households. Some of the advantages of the Cambodia livestock subsector are the increasing market demand: increasing domestic market for livestock and increasing demand from neighboring countries (especially cattle);the rich source of manure and other agricultural input such as transportation means, ploughing etc. More so, there is high expectation of the farmers experiencing increase in production since more supports are provided by both governmental and non-governmental organizations. On the other hand, the subsector witnesses some constraints including the low level of education of the livestock farmers, erratic market prices as a result of too many middlemen, local breed with low productivity and traditional management system still dominates the sub- sector. Scarcity of abled labor and seasonal cost is also one of the factors impeding the subsector to reaching it potential. This study suggests that to reach full potential in the livestock sector of Battambang of Cambodia, the government needs to address the infrastructural problems and private sector needs to be encouraged to invest in the sector in livestock input industries. 展开更多
关键词 potential CONSTRAINTS LIVESTOCK production Battambang Cambodia
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Estimates of potential new production in the Java-Sumatra upwelling system
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作者 韦惺 廖晓眉 +1 位作者 詹海刚 刘海龙 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第6期1063-1067,共5页
The Java-Sumatra upwelling is one of the most important upwelling systems in the Indian Ocean, with maximum upwelling intensity in July through August. To estimate the nitrate supplied by upwelling, we developed a thr... The Java-Sumatra upwelling is one of the most important upwelling systems in the Indian Ocean, with maximum upwelling intensity in July through August. To estimate the nitrate supplied by upwelling, we developed a three-dimensional hydrodynamic model to calculate the mean vertical speed and determine the depth of upwelling. We used in-situ vertical nitrate profiles to assess nitrate concentration in the upwelled waters, and calculated the nitrate supply as the product of nitrate concentration and vertical transport obtained from the numerical model. The calculated result represents potential new production generated in the upwelling region. We found that on the event time scale (monthly) of Java-Sumatra upwelling, water brought to the surface originated from locations 100-m deep, giving a nitrate supply of 93.77×10 3mol/s and potential new production of 1.02×10 14gC/a. 展开更多
关键词 Java-Sumatra upwelling system nitrate supply potential new production
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Ultrathin 3D radial tandem‐junction photocathode with a high onset potential of 1.15 V for solar hydrogen production
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作者 Shaobo Zhang Huiting Huang +8 位作者 Zhijie Zhang Jianyong Feng Zongguang Liu Junzhuan Wang Jun Xu Zhaosheng Li Linwei Yu Kunji Chen Zhigang Zou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第7期1842-1850,共9页
Combining a progressive tandem junction design with a unique Si nanowire(SiNW)framework paves the way for the development of high‐onset‐potential photocathodes and enhancement of solar hydrogen production.Herein,a r... Combining a progressive tandem junction design with a unique Si nanowire(SiNW)framework paves the way for the development of high‐onset‐potential photocathodes and enhancement of solar hydrogen production.Herein,a radial tandem junction(RTJ)thin film water‐splitting photo‐cathode has been demonstrated experimentally for the first time.The photocathode is directly fab‐ricated on vapor‐liquid‐solid‐grown SiNWs and consists of two radially stacked p‐i‐n junctions,featuring hydrogenated amorphous silicon(a‐Si:H)as the outer absorber layer,which absorbs short wavelengths,and hydrogenated amorphous silicon germanium(a‐SiGe:H)as the inner layer,which absorbs long wavelengths.The randomly distributed SiNW framework enables highly efficient light‐trapping,which facilitates the use of very thin absorber layers of a‐Si:H(~50 nm)and a‐SiGe:H(~40 nm).In a neutral electrolyte(pH=7),the three‐dimensional(3D)RTJ photocathode delivers a high photocurrent onset of 1.15 V vs.the reversible hydrogen electrode(RHE),accompanied by a photocurrent of 2.98 mA/cm^(2) at 0 V vs.RHE,and an overall applied‐bias photon‐to‐current effi‐ciency of 1.72%.These results emphasize the promising role of 3D radial tandem technology in developing a new generation of durable,low‐cost,high‐onset‐potential photocathodes capable of large‐scale implementation。 展开更多
关键词 Solar hydrogen production 3D radial tandem junction Amorphous silicon photocathode Very thin absorber High onset potential
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The Potential Scenarios of the Impacts of Climate Change on Egyptian Resources and Agricultural Plant Production 被引量:1
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作者 Mahmoud M. Fawaz Sarhan A. Soliman 《Open Journal of Applied Sciences》 2016年第4期270-286,共17页
The emissions of greenhouse gasses in Egypt are about 0.58% of the total emissions of the world in the year 2015, although Egypt is one of the countries most affected by the impacts of climate change. By assessment an... The emissions of greenhouse gasses in Egypt are about 0.58% of the total emissions of the world in the year 2015, although Egypt is one of the countries most affected by the impacts of climate change. By assessment and analysis of the expected economic impacts of climate change by the year 2030, the Egyptian cultivated area will be reduced to about 0.949 million acres, equal to about 8.22% of the Egyptian cultivated area compared with the case of no sinking part of the Delta land, thus reducing crop area in Egypt to about 1.406 million acres, approximately to about 6.25% of crop area compared with the case of no sinking part of the Delta land, in addition to surplus in the Egyptian balance water to about 2.48 billion m3. In this case value of the Egyptian agriculture production will decrease by about 6.19 billion dollars, equal to about 6.19% compared with presumably no sinking of the Delta land. In the case of sinking 15% of Delta lands, with the change of the productivity and water consumption of most crops, the result will be a reduction in the cultivated area to about 0.94 million acres. In addition to decreasing the Egyptian crop area to about 1.39 million acres, with a deficit in the Egyptian balance water to about 4.74 billion m3 compared to the case of no sinking part of the Delta land, the cultivated area will decrease to about 8.17%, and the crop area will decrease 6.18%. Also, the value of the Egyptian agriculture production will decrease by about 12.51%. While compared to sinking part of the Delta land to about 15% of the total Delta area without the other impacts of climate change, the cultivated area will increase by about 0.06%;the crop area will increase by about 0.08%;also, the value of the Egyptian agriculture production will decrease by about 5.57%. 展开更多
关键词 The potential Scenarios of the Impacts of Climate Change on Egyptian Resources and Agricultural Plant production
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Geothermal Energy Production Potential from Oil and Gas Fields in Western Ukraine
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作者 Oleksandr Burachok Oleksandr Kondrat 《Journal of Geological Resource and Engineering》 2019年第4期123-131,共9页
Western Ukraine as well as Crimea Peninsula is well known for their geothermal potential.The classic low enthalpy geothermal project is based on the construction of a binary power plant,and includes recycling of water... Western Ukraine as well as Crimea Peninsula is well known for their geothermal potential.The classic low enthalpy geothermal project is based on the construction of a binary power plant,and includes recycling of water through one or several doublets of wells;produced hot water is directed to a heat exchanger(vaporizer),in which a secondary(working)fluid with low boiling point and high vapor pressure vaporizes and rotates a turbine to produce electricity.The highest risk for the project is associated with drilling new wells,which may not hit the target or not have the required productivity.Western Ukraine is one of the oldest oil and gas production regions in Europe.The majority of the fields are on a late stage of the development that is characterized with high produced volumes of water that after separation is being reinjected back for pressure support.In this study,we evaluated the possibility of geothermal energy production,extracted from water that is produced together with oil and gas,based on numerical reservoir simulation models for a typical reservoir setting. 展开更多
关键词 WESTERN Ukraine GEOTHERMAL ENERGY ENERGY production potential sensitivity analysis RESERVOIR simulation
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The impact of salinity,alkalinity and nanoparticle concentration on zeta-potential of sand minerals and their implication on sand production
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作者 Abbass Kataya Ehsan Khamehchi Masoud Bijani 《Energy Geoscience》 2022年第3期314-322,共9页
The effect of brine salinity,cation type,pH,and produced sand on zeta potential(ZP)measurements with and without the presence of silica nanoparticles is investigated through pH measurement,static tests for sand and ZP... The effect of brine salinity,cation type,pH,and produced sand on zeta potential(ZP)measurements with and without the presence of silica nanoparticles is investigated through pH measurement,static tests for sand and ZP measurements as well as Field Emission Scanning Electron Microscope(FESEM)analyses.Three important factors were investigated:composition of the injected brine,surface charge and pH.Their influence on stability of nanoparticles in the injected brine and amount of sand segregation was determined and the analysis of the new outcomes based on rock/brine ZP measurements was reported.The results show that the use of silica nanoparticles with high pH helps in preventing sand production and that pH has a main effect on the surface charge of the sand particle released,affecting the ZP of the solution.Nanoparticles can be active as a coating on sand grains and prevent sand segregation during water flooding.Divalent cations have been found to acquire a more substantial impact on neutralizing the negative charge of the sand particles than monovalent cations at the same concentration and pH conditions at 25℃.The value of ZP becomes of higher negative value with the decrease of brine salinity.The effectiveness of SiO_(2)nanoparticles is quite different for soft water and smart water.For soft water,the nanoparticles work more effective at pH higher than 8;and for smart water,the nanoparticles perform better at pH lower than 8.To reduce sand production with the use of silica nanoparticles,it is highly suggested to increase pH,as pH and sand production mechanisms were observed to be inversely related. 展开更多
关键词 Sand production Zeta potential Silica nanoparticle Smart water Soft water pH effect
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Evaluation of Potential Fishery Productivity in Lihu Lake Based on GIS 被引量:3
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作者 段金荣 张红燕 +3 位作者 刘凯 徐东坡 张敏莹 施炜纲 《Agricultural Science & Technology》 CAS 2011年第9期1323-1326,共4页
[Objective] The paper was scientifically evaluate the potential fishery productivity of Lihu using GIS technology.[Method] The evaluation of potential fishery productivity in Lihu was based on GIS and AHP according to... [Objective] The paper was scientifically evaluate the potential fishery productivity of Lihu using GIS technology.[Method] The evaluation of potential fishery productivity in Lihu was based on GIS and AHP according to the characteristics of fisheries resources in Lihu Lake.The evaluation system included 3 sub-models including water quality,biodiversity and hydrological condition,which totally had 10 indexes.Judgment matrix was constructed based the advices of professors of fisheries resources,and the indicator’s weight were calculated by the process of AHP.The ranking distributing map of potential fishery productivity in Lihu was obtained by the model of raster analysis,raster calculator,spatial overlay and classification models of ARC/INFO.[Result] Potential fishery productivity of Lihu was divided into 4 grades in term of higher,high,general and low,and which covered 2.643 3,3.844 8,1.121 4 and 0.400 5 hm2,respectively.[Conclusion] The study provided theoretical basis for ecological reconstruction of Lihu Lake. 展开更多
关键词 potential fishery productivity EVALUATION GIS Lihu
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