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Comparison of Economical and Technical Indices on Rare Earth Separation Processes of Bastnasite by Solvent Extraction 被引量:2
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作者 严纯华 廖春生 +2 位作者 贾江涛 王明文 李标国 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第1期59-64,共6页
According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system wer... According to the composition of rare earth ores and the market, several feasible separation processes of bastnasite in Baotou of Inner Mongolia and Mianning of Sichuan by solvent extraction in HEH(EHP) HCl system were presented. The parameters of the processes such as stage numbers, volume of mixer settler, fixed investment of extractant and rare earths, consumption of chemical reagents including HCl and NH 3 were calculated and compared. The results show that the novel scheme can save cost more than 20% compared with those of others. By the economical analysis, the optimized separation process of bastnasite was obtained, which can be applied to the treatment of monazite too. 展开更多
关键词 Rare earths Bastnasite Solvent extraction economical index technical index
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Telecommunications and Energy Infrastructure Sharing: Technical and Socio-Economic Impact Analysis in a Multi-Operator Environment in Burundi
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作者 Apollinaire Bigirimana Jérémie Ndikumagenge +2 位作者 Sami Tabbane Romeo Nibitanga Hassan Kibeya 《Journal of Computer and Communications》 2024年第10期94-111,共18页
The sharing of telecommunications infrastructure and power supply equipment is currently an applicable and very common model for grouping signal transmission and reception equipment and their power supply on the same ... The sharing of telecommunications infrastructure and power supply equipment is currently an applicable and very common model for grouping signal transmission and reception equipment and their power supply on the same site to ensure coverage of fixed, mobile, Internet and radio and television broadcasting networks. This study consists of producing an inventory of telecommunications and energy infrastructure sharing, focusing on the one hand on analyzing the impacts of active and passive sharing of telecommunications infrastructure from a technical point of view, particularly in terms of legal framework, deployment, coverage and exposure to electromagnetic radiation, and on the other hand on identifying the effects of infrastructure sharing from a socio-economic point of view in a multi-operator mobile telephony environment, by indicating the economic value of the revenue generated as a result of infrastructure sharing. Finally, the results will contribute to identify strategies for ensuring maximum deployment and coverage of the country, and for developing the information and communication technologies (ICT) sector in order to contribute to the digital transformation by digitising services using mobile telephony and the Internet in Burundi. 展开更多
关键词 Infrastructure Sharing Mobile Telephony Energy Multi-Operators Environment technical and Socio-economic Impact
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Technical and Economical Problems of Bituminous Coal Mining in Czech Republic
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作者 Jaroslav Dvoracek (VSB-Technical University of Ostrava, Czech Republic) 《International Journal of Mining Science and Technology》 SCIE EI 1998年第1期5-9,共5页
The historical development of mining industry in Czech Republic, mining industry in new economical conditions, damping program of hituminous coal mining and the damping of mining activity are mentioned in this paper, ... The historical development of mining industry in Czech Republic, mining industry in new economical conditions, damping program of hituminous coal mining and the damping of mining activity are mentioned in this paper, and some important and detail data are given. This paper is not only concerned to mining, but also to social society, so it is of significance to mining industry and otber enterprises. 展开更多
关键词 Czech REPUBLIC technical and economical PROBLEMS bituminous joint-stock company
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To Raise Safe and Economical Operation Level on Scientific and Technical Progress Basis
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《Electricity》 1997年第1期20-22,共3页
关键词 To Raise Safe and economical Operation Level on Scientific and technical Progress Basis
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Technical and economic demands of HVDC submarine cable technology for Global Energy Interconnection 被引量:8
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作者 Xiaoling Zhao Yao Liu +4 位作者 Jiawei Wu Jinyu Xiao Jinming Hou Jinghui Gao Lisheng Zhong 《Global Energy Interconnection》 2020年第2期120-127,共8页
Power transmission across the sea is an important part of global energy interconnection(GEI).To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind ... Power transmission across the sea is an important part of global energy interconnection(GEI).To support the construction of GEI and to serve the needs of future clean energy trans-sea transportation and offshore wind power development,this study a)analyzes the requirements of the GEI backbone network pertaining to direct current(DC)submarine cable technology,and b)defines the key technical and economic indices of ultrahigh-voltage direct current(UHVDC)submarine cable based on theoretical computations.The research is based on the thermoelectric coupling model and the finite element method.It is shown that the dielectric strength of the insulating materials of the±800 kV~±1100 kV/4000 MW^12000 MW UHVDC submarine cable(extrusion insulation)should be not less than 43~65 kV/mm,while the heat resistance is not less than 110°C.As the cost of submarine cable is 5~10 times higher than that of the overhead line,the project investment need to be decreased to a level within the economical carrying capacity to guarantee extensive applicability of the HVDC submarine cable technology. 展开更多
关键词 UHVDC submarine cable GEI technical index economic index
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Measurement of Technical, AIIocative and Economic Efficiency of Tomato Farms in Northern Pakistan 被引量:10
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作者 Himayatullah Khan 《Journal of Agricultural Science and Technology(B)》 2012年第10期1080-1090,共11页
The study measures productive efficiency of tomato growers in village Akbarpura of Disctrict Nowshera in Khyber Pakhtunkhwa (KPK) province of Northern Pakistan. The study uses household level data collected in summe... The study measures productive efficiency of tomato growers in village Akbarpura of Disctrict Nowshera in Khyber Pakhtunkhwa (KPK) province of Northern Pakistan. The study uses household level data collected in summer 2010 from sample farmers selected by multi-staged sampling. The study uses a theoretical framework to measure productive efficiency and estimates the Cobb-Douglas frontier production and cost models. The study found that technical efficiency indices varied significantly, with technical efficiency index averaging at 65%. The indices of allocative efficiency also varied widely, with an average of 56%. There was a wide gap between the highest and lowest economic efficiency indices, with a mean economic efficiency of 35%. The study concluded that farmer education, extension visits, age and access to credit contributed significantly and positively to productive efficiencies. A policy implication of this study is that there is enough potential for farmers to increase tomato production and net profits. The study recommends that the government should further invest in public education and strengthen extension services farmer education and because extension visits constituted important determinants of productive efficiencies. 展开更多
关键词 Frontier production and cost function technical efficiency allocative efficiency economic efficiency inefficiencydeterminants Pakistan.
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Technical and Structural Effects of China's TFP Growth 被引量:1
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作者 Cai Yuezhou Fu Yifu 《China Economist》 2018年第5期47-59,共13页
TFP growth may derive from both technology progress(technical effect) and factor allocation(structural effect). Using China's macroeconomic and industrial data, this paper decomposes China's TFP growth on the ... TFP growth may derive from both technology progress(technical effect) and factor allocation(structural effect). Using China's macroeconomic and industrial data, this paper decomposes China's TFP growth on the basis of growth accounting to cast light on China's growth sources since reform and opening up in 1978. Our study has led to the following findings:(1) From 1978 to 2014, China's economic growth was of generally good quality, and about 1/3 of growth momentum stemmed from a general technology improvement.(2) After 2005, China's late-mover advantage diminished due to narrowed technology gaps with advanced economies. This resulted in a sharp decline in the contribution of technology progress to growth. However, structural effect contributed a steadily increasing share to China's growth.(3) After global financial crisis in 2008, there has been a tendency of reverse technology progress in terms of factor allocation in sectors with excess industrial capacity and other sectors like finance and real estate. Therefore, China should divert its factor resources to more tech-intensive and efficient sectors in the short run, and strive to promote technology progress in all sectors in a longer timeframe. 展开更多
关键词 TFP technical effect STRUCTURE effect GROWTH ACCOUNTING
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Economic and Technical Analysis of a Reverse-Osmosis Water Desalination Plant Using DEEP-3.2 Software 被引量:1
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作者 Ali AI-Karaghouli Larry Kazmerski 《Journal of Environmental Science and Engineering(A)》 2012年第3期318-328,共11页
Reverse osmosis (RO) is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology wi... Reverse osmosis (RO) is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology with a greater number of installations around the world. The economic and technical performance of a medium-capacity RO desalination plant (2,000 m^3/day) proposed to be installed in Umm Qasr city south of Basra, Iraq is analyzed using DEEP-3.2 software created by the International Atomic Energy Agency (IAEA). This port city is located on the Gulf shore and does not have any fresh water resources. The analysis shows that the cost of fresh water produced by this plant is US$0.986/m^3 with a good quality of fresh water (279 ppm), which is a reasonable price for this remote area. The analysis also shows an increase in water production cost of about 12% at increased electricity price from 0.06 to 0.1 US$/kWh, 53% when the seawater salinity increased from 35,000 to 45,000 ppm, 2.5% when the seawater temperature decreased from 33 ℃ to 20 ℃, and 0.71% when the interest rate increased from 0% to 5%. Pumping fresh water from the Basra purification plant (located 175 km north of Umm Qasr) is 22.16 times the cost and 236.7% poorer quality than the fresh water produced by the RO plant. 展开更多
关键词 Water desalination reverse osmosis DEEP-3.2 software economic analysis technical analysis.
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The Application of Reinforcement Theory in the Review Stage of English Teaching and Learning in Chinese Higher Vocational and Technical Colleges
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作者 Keren Pan 《Journal of Contemporary Educational Research》 2024年第8期88-94,共7页
Reinforcement theory is a behavioral psychology theory proposed by Skinner,which has been widely applied in various fields such as management and education.Positive reinforcement and negative reinforcement are the two... Reinforcement theory is a behavioral psychology theory proposed by Skinner,which has been widely applied in various fields such as management and education.Positive reinforcement and negative reinforcement are the two types of reinforcement.By adopting these two different reinforcement methods appropriately,human behavior can develop in a positive direction.In the review stage of English teaching and learning in Chinese higher vocational and technical colleges,the use of different reinforcement methods based on various classes,individuals,conditions,and environments can effectively promote or change the behavior of teachers and students,thereby improving the effectiveness of the review. 展开更多
关键词 Reinforcement theory Higher vocational and technical colleges English teaching and learning REVIEW effectiveness
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The Transformer Equipment Selection’s Update Decision Technical and Economic Analysis Model
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作者 Jincheng Shang Zhongfu Tan +1 位作者 Chen Zhang Liwei Ju 《Energy and Power Engineering》 2013年第4期143-147,共5页
Based on the current situation of the domestic transformer equipment selection, the paper analyses the SH15, S11 and S9 transformer from the angles of annual running power consumption, payback period, energy efficienc... Based on the current situation of the domestic transformer equipment selection, the paper analyses the SH15, S11 and S9 transformer from the angles of annual running power consumption, payback period, energy efficiency of the transformer, furthermore, determine the best optimal capacity, load factor and update Year of the SH15-type transformers. Example analysis results show that, from the point of view of the technical and economic the SH15-type transformer has better economic and environmental benefits, and large capacity SH15 transformer better comprehensive benefits. 展开更多
关键词 TRANSFORMER Equipment UPDATES DECISION technical and economIC Analysis
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A Foreign-Oriented Economic Entity——Wenzhou Economic and Technical Development Corporation
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作者 Chen Xinjiang 《China's Foreign Trade》 1994年第10期17-17,共1页
Located at 30 Lucheng Road, Wenzhou, the Wenzhou Economic and Technical Development Corporation(WETDC) was founded in September 1985. It was granted of self-operational rights for imports and exports by the former Min... Located at 30 Lucheng Road, Wenzhou, the Wenzhou Economic and Technical Development Corporation(WETDC) was founded in September 1985. It was granted of self-operational rights for imports and exports by the former Ministry of Foreign Economic Relations and Trade in November 1992. The corporation is a special composite foreign trade company, integrating 展开更多
关键词 US over A Foreign-Oriented economic Entity Wenzhou economic and technical Development Corporation
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Technical, Economic and Environmental Evaluation on Mechanical Rice Straw Gathering Method
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作者 Nguyen Thanh Nghi Nguyen Duc Canh +2 位作者 Hau Duc Hoa Nguyen Van Hung Martin Gummert 《Journal of Environmental Science and Engineering(B)》 2015年第11期614-619,共6页
Rice straw is a rice by-product, which is currently mostly wasted in Vietnam, in particular in the Mekong delta. At present, the cost of straw gathering is increasing because of the increased use of combine harvesters... Rice straw is a rice by-product, which is currently mostly wasted in Vietnam, in particular in the Mekong delta. At present, the cost of straw gathering is increasing because of the increased use of combine harvesters. High labor cost and lack of labor makes manual collection unfeasible. Farmers therefore often just burn it, which causes pollution, increased greenhouse gas emissions and loss of opportunities to value add. An economic and environmental evaluation and technical field testing of a straw baler with 4 ha/day capacity was therefore conducted in Long An province. During the field testing data on the gathering capacity, fuel consumption, labor requirement and other cost items were collected. The test results showed that the baling cost is US$19.0 per ton of rice straw, the pay-back period of 2. 1 years and the internal rate of return of 38%. In addition to the baling cost, the transportation cost varies from US$24 for a distance of 100 km to US$32 for 150 km. The benefits of the machine are not only economical but also include the reduction of field burning. 展开更多
关键词 Rice straw gathering technical and economic evaluation environmental benefits.
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Brief Introduction of Zhejiang Economic and Technical Cooporation Corporations
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《China's Foreign Trade》 1995年第4期33-33,共1页
1. Zhejiang General Construction Engineering Corporation (Group) The corporation has completed 20 million sqm of medium-to-large industrial projects and various civil construction. It mainly involves in the constructi... 1. Zhejiang General Construction Engineering Corporation (Group) The corporation has completed 20 million sqm of medium-to-large industrial projects and various civil construction. It mainly involves in the construction of a chemical fertilizer factory with an annual production capacity of 300, 000 tons of synthetic ammonia and 520, 000 tons of urea, a refinery, producing 2.5 million tons of crude oil, two 300, 000-kw and 600, 000-kw power plants, highway, highway bridges and more than 30-storey hotels. It has projects contracted with Guinea, Sierra Leone, Kuwait, Iraq, Yemen, Myanmar, Japan, Malaysia, Singapore and Russia. 展开更多
关键词 In Brief Introduction of Zhejiang economic and technical Cooporation Corporations than
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Langfang Economic and Technical Development Zone
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《China's Foreign Trade》 1995年第5期35-36,共2页
The Langfang Economic and Technical Development Zone is situated at the entry/exit of the Beijing-Tianjin-Tangshan Expressway, with a designed area of 14 sq km. The first-stage construction in the zone will cover an a... The Langfang Economic and Technical Development Zone is situated at the entry/exit of the Beijing-Tianjin-Tangshan Expressway, with a designed area of 14 sq km. The first-stage construction in the zone will cover an area of 2.2 sq kms. The zone is 40 kms away from Beijing, 60 km from Tianjin, 105 kms from Tianjin New Harbour, and only six kms from Langfang Railway Station. Telecommmunications facilities in the zone are connected with a 10, 000-line programme-controlled telephone switchboard imported by the city from Canada, 500-line long-distance automatic telephone equipment, and 展开更多
关键词 LINE Langfang economic and technical Development Zone
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Sino-Burma economic, trade, technical cooperation project:Panglang Hydropower Station
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《Electricity》 2001年第1期51-51,共1页
关键词 Sino-Burma economic technical cooperation project TRADE
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Wuhu Economic and Technical Development Zone
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《China's Foreign Trade》 1996年第8期78-78,共1页
Located in the southeast of AnhuiProvince, beside the Yangtze River, and atthe west verge of the Yangtze Delta, Wuhu isan open riverside city approved by the state,and a port opening to foreign ships,performing a link... Located in the southeast of AnhuiProvince, beside the Yangtze River, and atthe west verge of the Yangtze Delta, Wuhu isan open riverside city approved by the state,and a port opening to foreign ships,performing a link function in the generalstrategy of the Yangtze River, with Shanghaias the head and three gorges as the pillar. The Wuhu Economic and TechnicalDevelopment Zone, approved by the StateCouncil is the key point to developingWanjiang and responding Pudong. With aplanned area of 10 sq km, the zone is close 展开更多
关键词 Wuhu economic and technical Development Zone
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Brief Introduction of Zhejiang Economic and Technical Cooperation Corporations
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《中国对外贸易》 1995年第4期32-32,共1页
1 Zhejiang General Construction Engineering Corporation(Group) The corporation has completed 20 million sqm of medium-to-large industrial projects and various civil construction Itmainly involves in the construction o... 1 Zhejiang General Construction Engineering Corporation(Group) The corporation has completed 20 million sqm of medium-to-large industrial projects and various civil construction Itmainly involves in the construction of a chemical fertilizerfactory with an annual production capacity of 300,000 tons ofsynthetic ammonia and 520,000 tons of urea,a refinery,producing2.5 million tons of crude oil,two 300,000-kw and 600,000-kwpower plants.highway,highway bridges and more than 30-storey hotels.It has projects contracted with Guinea,SierraLeone.Kuwait,Iraq,Yemen,Myanmar,Japan,Malaysia,Singapore and Russia. 展开更多
关键词 Brief Introduction of Zhejiang economic and technical Cooperation Corporations THAN
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Projects for Anqing Foreign Economic and Technical Cooperation
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《China's Foreign Trade》 1996年第8期32-32,共1页
Project No.:96-010Name:Anqing Changjiang Highway BridgeUnit:Anqing Municipal GovernmentContent:Introducing foreign funds and equipmentto build Anqing Changjiang Highway Bridge.Environment:The project to be built is on... Project No.:96-010Name:Anqing Changjiang Highway BridgeUnit:Anqing Municipal GovernmentContent:Introducing foreign funds and equipmentto build Anqing Changjiang Highway Bridge.Environment:The project to be built is one of theimportant bridges in Anhui Province and CentralChina.Anqing is to its north and ChizhouPrefecture to its south.Influential area coversAnqing City,Chizhou Prefecture,Huaugshan City,Tongling City,Hefei City,Caohu Prefecture,Liuan Prefecture,as well as the whole province. 展开更多
关键词 Projects for Anqing Foreign economic and technical Cooperation
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'95 Technical and Economic Indexes of CNPC's Oil Producing Units
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《China Oil & Gas》 CAS 1996年第2期92-92,共1页
'95TechnicalandEconomicIndexesofCNPC'sOilProducingUnits¥//'95 Technical and Economic Indexes of CNPC's Oil Producing Units...
关键词 CNPC technical and economic Indexes of CNPC’s Oil Producing Units
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Main Technical Economic Indicator of Chinese Oilfields
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《China Oil & Gas》 CAS 1999年第1期28-28,共1页
关键词 Main technical economic Indicator of Chinese Oilfields
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