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Solution to the Horizontal Crossing Problem of Transportation System at Key Points in Open-Pit Mines
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作者 Tao DONG Ling LIU 《Asian Agricultural Research》 2024年第7期36-38,47,共4页
In order to reduce the horizontal crossing transportation problems between coal trucks and stripping trucks,large and small vehicles,and transport trucks and belt conveyors at key points of open pit mine in production... In order to reduce the horizontal crossing transportation problems between coal trucks and stripping trucks,large and small vehicles,and transport trucks and belt conveyors at key points of open pit mine in production,the separate transportation mode of underpass bridge and overpass steel trestle is proposed to optimize the open pit development transportation system,so as to solve the practical problems that the horizontal cross of transport vehicles causes vehicle blockage,affects production schedule and production safety.The results show that the horizontal crossing road can be changed into a separate type of overpass steel trestle,which can realize the classified transportation of large and small vehicles,reduce the traffic density,make vehicles with different functions go their own way,eliminate the hidden danger of traffic accidents,and improve the production efficiency. 展开更多
关键词 Open-pit mines Cross-transport Underpass bridge Overpass steel trestle Production efficiency
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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:3
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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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The Effect of Nitrogen Gas Cooling Which Is Used in Aluminium Extrusion Mold on Production Efficiency 被引量:1
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作者 Merve Ozcan Cemal Ozsut +1 位作者 Oguzhan Deveci Gulbahar Bentesen 《Open Journal of Applied Sciences》 2021年第4期414-421,共8页
It is aimed to investigate the efficiency of nitrogen gas cooling which is used in aluminium extrusion mold in this study. The exit temperature of extrusion profile increases depending on heat generated by friction an... It is aimed to investigate the efficiency of nitrogen gas cooling which is used in aluminium extrusion mold in this study. The exit temperature of extrusion profile increases depending on heat generated by friction and forming. This situation can cause to surface defects such as hot cracks and grain thickening after extrusion process. Cooling of the mold has a critical role in terms of dissipating heat close to the forming zone. Local internal cooling experiments were performed in the hot aluminium extrusion mold within the scope of this study. It has been obtained that exit temperature of the aluminium extrusion profile can be significantly reduced in experimental results. Also it was found that the reduction of press time (s) and increase of press speed (mm/s). This paper focuses the effect of nitrogen gas cooling on extrusion mold for process efficiency. The extrusion parameters were performed for comparative analysis. Its obtained that process ensures efficiency. 展开更多
关键词 Aluminium Extrusion Mold Cooling System Production efficiency
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Measurement of Grain Production Efficiency in Main Grain-producing Areas and Analysis of Inter-provincial Differences--A Study Based on Super-SBM Model and Malmquist Index
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作者 Qi Heng Su Jing-yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2022年第2期86-96,共11页
China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-p... China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-producing areas has become the fundamental way to strengthen the grain production capacity and improve the national food security capability,and to improve the efficiency of grain production in major grain-producing areas requires empirical support.This paper used the Super SBM model and the Malmquist index to measure the grain production efficiency of the main grain-producing areas from 2001 to 2020 from both static and dynamic perspectives,and compared the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas.The results showed that from 2001 to 2020,the grain production in the main grain-producing areas was in a relatively ineffective state,and the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas were obvious.The order of grain production efficiency in different soil types was black soil region>red-yellow soil region>paddy soil region>fluvo-aquic soil region,and the order of grain production efficiency of the provinces(autonomous regions)in the main grain-producing areas was Jilin>Heilongjiang>Inner Mongolia>Jiangxi>Hunan>Sichuan>Hubei>Jiangsu>Liaoning>Henan>Anhui>Shandong>Hebei.From 2001 to 2020,the total factor productivity of grain in the main grain-producing areas increased,but due to the trade-off between the technological progress and the growth of technical efficiency,the increase in the total factor productivity of grain in the main grain-producing areas was small,and the growth mainly came from the increase of input factors in this period.The total factor productivity of grain in Hebei,Heilongjiang,Liaoning,Jilin,Inner Mongolia,Shandong,Jiangsu,Henan and Anhui increased,but the increase was small,while the total factor productivity of grain in Jiangxi,Sichuan,Hunan and Hubei provinces declined. 展开更多
关键词 main grain-producing area grain production efficiency inter-provincial difference
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Calculation of Agricultural Production Efficiency Based on a Three-stage Data Envelopment Analysis Model and Analysis of the Spatial-temporal Characteristics: A Case Study of the Yangtze River Economic Belt
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作者 Wenjun ZHUO Haiyang CUI 《Meteorological and Environmental Research》 CAS 2021年第5期68-76,83,共10页
In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,th... In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,the Yangtze River Economic Belt is adjusting the agricultural industry structure,optimizing the input-output ratio,and ensuring stable and sustainable agricultural production. Based on the combination of the three-stage Data Envelopment Analysis( DEA) model and cluster analysis,this study examined the Yangtze River Economic Belt from 2008 to 2018 to measure its agricultural production efficiency and to analyze its temporal and spatial characteristics. Studies showed that exogenous environmental factors significantly( P < 5%) impacted agricultural production efficiency in the Yangtze River Economic Zone,and there were temporal and spatial differences. These included:(1) after excluding environmental factors,the overall agricultural production efficiency of the Yangtze River Economic Zone had improved. Sichuan Province and Jiangsu Province were at the forefront of efficiency,whereas the agricultural production efficiency of Shanghai had declined obviously.(2) The agricultural production efficiency of the Yangtze River Economic Belt varied year by year,with fluctuating development. The middle reaches of the Yangtze River had advanced agricultural production efficiency more than the upstream and downstream regions,and the agricultural production efficiency of the individual provinces did not match their economic and social development.(3) Increases in labor,land,irrigation,and other input factors increased agriculture production efficiency,and there was no correlation between fiscal investment,per capita gross domestic product( GDP) and agricultural production efficiency,while the disaster-affected area had a significantly negative impact on agricultural production efficiency. 展开更多
关键词 Agricultural production efficiency Three-stage Date Envelopment Analysis Temporal and spatial characteristics Yangtze River Economic Belt
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Learning Effect and Productivity Convergence of Chinese Industrial Enterprises
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作者 Tinghua Liu Jingru Wang Xiao Liu 《Journal of Finance Research》 2020年第2期92-105,共14页
The main purpose of this paper is to test the production efficiency of different Chinese property industrial enterprises.Based on the large sample panel data of industrial enterprises of the National Bureau of Statist... The main purpose of this paper is to test the production efficiency of different Chinese property industrial enterprises.Based on the large sample panel data of industrial enterprises of the National Bureau of Statistics,we found that although the production efficiency of China-funded enterprises is generally weaker than foreign-funded enterprises,some China-funded enterprises have better learning ability.On the one hand,dynamic analysis found that private enterprises have significant learning ability.On the other hand,the results of convergence analysis show that China’s private enterprises have the potential to gradually catch up with the frontier level of world production efficiency and have better learning ability to catch up potential.And state-owned enterprises tend to be more efficient at the beginning of their establishment,but their productivity is fairly slow to improve,especially for state-owned enterprises with high efficiency sub-samples,so that it’s hard for them to continue improving their efficiency.Institutional analysis found that the marketization process helped the China enterprises to improve their learning ability and China should continue to strengthen the reform of property rights and promote the marketization process. 展开更多
关键词 Production efficiency Learning effect efficiency catch-up βconvergence analysis
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Spatial differentiation and evolution trend of technical efficiency of forestry production in china
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作者 Xu Yang 《Proceedings of Business and Economic Studies》 2021年第1期1-5,共5页
Based on the non-radial super-efficiency SBM model,the technical efficiency of forestry production in 30 provinces(municipalities,autonomous regions)across the country was measured from 2004 to 2018,and the Makov chai... Based on the non-radial super-efficiency SBM model,the technical efficiency of forestry production in 30 provinces(municipalities,autonomous regions)across the country was measured from 2004 to 2018,and the Makov chain was introduced to analyze the evolution trend.The research found that:The average PTE of China's forestry from 2004 to 2018 was 0.516,and the overall level was not high;regional imbalances were prominent,showing a distribution pattern of"high in the south and low in the north"and"high in the east and low in the west".Regions with low and high levels of Forestry PTE have certain characteristics of"path dependence".in the long run,Forestry PTE growth will face greater pressure. 展开更多
关键词 FORESTRY Production technology efficiency Makov chain
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Practical Analysis of Mechanical Automation Technology in Automobile Manufacturing
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作者 Miao Zhang 《Journal of Electronic Research and Application》 2023年第5期24-29,共6页
In today’s rapidly developing modern society,automobiles,as an important part of transportation and industrial fields,play a pivotal role.With the improvement of people’s living standards and the increase in traffic... In today’s rapidly developing modern society,automobiles,as an important part of transportation and industrial fields,play a pivotal role.With the improvement of people’s living standards and the increase in traffic demand,the automobile manufacturing industry has been continuously developing and growing globally.However,to cope with increasingly fierce market competition and ever-changing consumer demands,the automobile manufacturing industry is also facing the challenges of improving production efficiency,reducing costs,and improving product quality.In this context,automation technology has gradually become a major trend in the automobile manufacturing industry.As an important support of modern industry,automation technology has shown great application potential in many fields.From industrial production to daily life,automation technology can be seen everywhere.In the field of manufacturing,especially in automobile manufacturing,the application of automation technology is getting more and more attention.Automated production lines,intelligent robots,and automated warehousing systems have all changed the face of automobile manufacturing to varying degrees,bringing companies higher efficiency,more stable quality,and greater competitive advantages.The application trend of this automation technology in various fields not only meets the needs of modern industry for efficient,precise,and sustainable development but also provides new ideas and paths for the future development of the automobile manufacturing industry. 展开更多
关键词 Mechanical automation technology Automobile manufacturing Practical analysis Production efficiency
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Which type of forest management provides most ecosystem services? 被引量:2
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作者 Timo Pukkala 《Forest Ecosystems》 SCIE CSCD 2016年第3期190-205,共16页
Background: Forest ecosystems are increasingly seen as multi-functional production systems, which should provide, besides timber and economic benefits, also other ecosystem services related to biological diversity, r... Background: Forest ecosystems are increasingly seen as multi-functional production systems, which should provide, besides timber and economic benefits, also other ecosystem services related to biological diversity, recreational uses and environmental functions of forests. This study analyzed the performance of even-aged rotation forest management (RFM), continuous cover forestry (CCF) and any-aged forestry (AAF) in the production of ecosystem services. AAF allows both even-aged and uneven-aged management schedules. The ecosystem services included in the analyses were net present value, volume of harvested timber, cowberry and bilberry yields, scenic value of the forest, carbon balance and suitability of the forest to Siberian jay. Methods: Data envelopment analysis was used to derive numerical efficiency ratios for the three management systems. Efficiency ratio is the sum of weighted outputs (ecosystem services) divided by the sum of weighted inputs. The linear programing model proposed by Charnes, Cooper and Rhodes was used to derive the weights for calculating efficiency scores for the silvicultural systems. Results and conclusions: CCF provided more ecosystem services than RFM, and CCF was more efficient than RFM and AAF in the production of ecosystem services. Multi-objective management provided more ecosystem services (except harvested timber) than single-objective management that maximized economic profitability. The use of low discount rate (resulting in low cutting level and high growing stock volume) led to better supply of most ecosystems services than the use of high discount rate. RFM where NPV was maximized with high discount rate led to particularly poor provision of most ecosystem services. In CCF the provision of ecosystem services was less sensitive to changes in discount rate and management objective than in RFM. 展开更多
关键词 Data envelopment analysis Production efficiency Multi-objective management Multi-functional forestry Continuous cover forestry Rotation forest management Any-aged forestry
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Aboveground biomass and net primary production of semi-evergreen tropical forest of Manipur,north-eastern India 被引量:2
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作者 L. Supriya Devi P.S Yadava 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A2期151-155,共5页
The aboveground biomass dynamics and net primary productivity were investigated to assess the productive potential of Dipterocarpus forest in Manipur, Northeast India.Two forest stands(stand I and II) were earmarked r... The aboveground biomass dynamics and net primary productivity were investigated to assess the productive potential of Dipterocarpus forest in Manipur, Northeast India.Two forest stands(stand I and II) were earmarked randomly in the study site for the evaluation of biomass in the different girth classes of tree species by harvest method.The total biomass was 22.50 t·ha-1 and 18.27 t·ha-1 in forest stand I and II respectively.Annual aboveground net primary production varied from 8.86 to 10.43 t·ha-1 respectively in two forest stands(stand I and II).In the present study, the values of production efficiency and the biomass accumulation ratio indicate that the forest is at succession stage with high productive potential. 展开更多
关键词 BIOMASS net primary production ACCUMULATION production efficiency
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Three-Dimensional Numerical Modeling of an Ar-N_2 Plasma Arc Inside a Non-Transferred Torch 被引量:2
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作者 B.SELVAN K.RAMACHANDRAN +2 位作者 K.P.SREEKUMAR T.K.THIYAGARAJAN P.V.ANANTHAPADMANABHAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第6期679-687,共9页
A three-dimensional numerical model is developed to study the behaviour of an argon-nitrogen plasma arc inside a non-transferred torch. In this model, both the entire cathode and anode nozzle are considered to simulat... A three-dimensional numerical model is developed to study the behaviour of an argon-nitrogen plasma arc inside a non-transferred torch. In this model, both the entire cathode and anode nozzle are considered to simulate the plasma arc. The argon-nitrogen plasma arc is simulated for different arc currents and gas flow rates of argon. Various combinations of arc core radius and arc length, which correspond to a given torch power, are predicted. A most feasible combination of the same, which corresponds to an actual physical situation of the arc inside the torch, is identified using the thermodynamic principle of minimum entropy production for a particular torch power. The effect of the arc current and gas flow rate on the plasma arc characteristics and torch efficiency is explained. The effect of the nitrogen content in the plasma gas on the torch power and efficiency is clearly detected. Predicted torch efficiencies are comparable to the measured ones and the effect of the arc current and gas flow rate on predicted and measured efficiencies is almost similar. The efficiency of the torch, cathode and anode losses and core temperature and velocity at the nozzle exit are reported for five different cases. 展开更多
关键词 plasma arc numerical modeling plasma torch minimum entropy production electro-thermal efficiency
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Functions of Nitrogen,Phosphorus and Potassium in Energy Status and Their Influences on Rice Growth and Development 被引量:1
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作者 MA Jiaying CHEN Tingting +8 位作者 LIN Jie FU Weimeng FENG Baohua LI Guangyan LI Hubo LI Juncai WU Zhihai TAO Longxing FU Guanfu 《Rice science》 SCIE CSCD 2022年第2期166-178,共13页
Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamb... Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamber for 20 d at 30℃/24℃day/night)under natural sunlight conditions with different nutrient regimes.The results showed that N had the strongest influence on the plant growth and development,followed by P and K.The highest nonstructural carbohydrate content,dry matter weight,net photosynthetic rate(Pn),ATP content,as well as NADH dehydrogenase,cytochrome oxidase and ATPase activities were found in the plants that received sufficient N,P and K.The lowest values of these parameters were detected in the N-deficient plants.Higher dry matter accumulation was observed in the K-deficient than in the P-deficient treatments,but there was no significant difference in the ratio of respiration rate to Pn between these two treatments,suggesting that differences in energy production efficiency may have accounted for this result.This hypothesis was confirmed by higher ATP contents and activities of NADH dehydrogenase,cytochrome oxidase and ATPase in the K-deficient plants than in the P-deficient plants.We therefore inferred different abilities in energy production efficiency among N,P and K in rice seedlings,which determined rice plant growth and development. 展开更多
关键词 RICE nutrient element PHOTOSYNTHESIS RESPIRATION plant growth and development energy production efficiency
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Comparative effects of nitrogen application on growth and nitrogen use in a winter wheat/summer maize rotation system 被引量:8
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作者 YIN Min-hua LI Yuan-nong XU Yuan-bo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期2062-2072,共11页
The application of fertilizer in agricultural production has become universally common for achieving high crop yields and economic benefits, but it has potential impacts on food safety, energy crisis and environmental... The application of fertilizer in agricultural production has become universally common for achieving high crop yields and economic benefits, but it has potential impacts on food safety, energy crisis and environmental pollution. Optimal management of fertilization is thus necessary for maintaining sustainable agriculture. Two-year(2013–2015) field experiment was conducted, in Yangling(108°24′E, 34°20′N, and 521 m a.s.l.), Shaanxi Province, China, to explore the effects of different nitrogen(N) applications on biomass accumulation, crop N uptake, nitrate N(NO_3~–-N) distribution, yield, and N use with a winter wheat/summer maize rotation system. The N applications consisted of conventional urea(U)(at 80(U80), 160(U160), and 240(U240) kg N ha^(–1); 40% applied as a basal fertilizer and 60% top-dressed at jointing stage) and controlled-release urea(CRU)(at 60(C60), 120(C120), 180(C180), and 240(C240) kg N ha~(^(–1)); all applied as a basal fertilizer) with no N application as a control(CK). The continuous release of N from CRU matched well with the N demands of crop throughout entire growing stages. Soil NO_3~–-N content varied less and peaked shallower in CRU than that in urea treatments. The differences, however, were smaller in winter wheat than that in summer maize seasons. The average yield of summer maize was the highest in C120 in CRU treatments and in U160 in urea treatments, and apparent N use efficiency(NUE) and N agronomic efficiency(NAE) were higher in C120 than in U160 by averages of 22.67 and 41.91%, respectively. The average yield of winter wheat was the highest in C180 in CRU treatments and in U240 in urea treatments with C180 increasing NUE and NAE by averages of 14.89 and 35.62% over U240, respectively. The annual yields under the two N fertilizers were the highest in C120 and U160. The results suggested that CRU as a basal fertilizer once could be a promising alternative of urea as split application in semiarid areas. 展开更多
关键词 controlled-release urea nitrogen availability soil fertility nitrogen use efficiency soil productivity
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Population status and regeneration of a tropical clumping bamboo Schizostachyum dullooa under two management regimes
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作者 Arun Jyoti Nath Ashesh Kumar Das 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期43-46,共4页
Schizostachyum dullooa (Gamble) Majumder 'dolu bamboo' is a thin walled sympodial moderate sized to large tufted bamboo, dominant in the successional fallows of northeast India. The impact of resource management o... Schizostachyum dullooa (Gamble) Majumder 'dolu bamboo' is a thin walled sympodial moderate sized to large tufted bamboo, dominant in the successional fallows of northeast India. The impact of resource management on productivity and sustainability of the species was evaluated by investigating the population status and regeneration in Cachar tropical semi evergreen forest under private property resource management (PPRM) and common property resource management (CPRM) regimes. Population status revealed current-year, one-year, two-year and three-year-old culms contribute 54%, 24%, 16% and 6% of the total culms per clump, respectively, under PPRM. Three-year-old culms were absent in CPRM and population status was thus represented by current year (83%), one-year (16%) and two-year (1%) old culms. Net change, rate of change and % gain in population for different age classes showed the prevalence of management practices under CPRM was unscientific. Efficiency of new culm production per clump used as an index of regeneration was 69.7% in PPRM and 59.88% in CPRM. New culms produced under CPRM were small and thin. We conclude that CPRM is inappropriate for a long term economic and ecological sustainability of the species and alternative management protocols are needed for conservation of the species. 展开更多
关键词 management regime population structure production efficiency Schizostachyum dullooa
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Synthesis and Photo-acid Generation of a Novel Bis(trichloromethyl)-1,3,5-triazine
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作者 JIANG Yu-ren LI Jin-liang XU Hui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第6期870-875,共6页
A new environmentally friendly photo-acid generator(PAG), 1-{4'-[4,6-bis(trichloromethyl)-1,3,5-triazin- 2-yl] [ 1, 1'-biphenyl]-4-yl}-O-acetyloxime ethanone(TZ4) consisting of both an oxime ester group and a ... A new environmentally friendly photo-acid generator(PAG), 1-{4'-[4,6-bis(trichloromethyl)-1,3,5-triazin- 2-yl] [ 1, 1'-biphenyl]-4-yl}-O-acetyloxime ethanone(TZ4) consisting of both an oxime ester group and a triazine group was designed and synthesized. From the measurements of absorption, fluorescence and the photo-acid generation, it was found that the novel PAG has an excellent radical-generating efficiency. And the other three bis-(trichloromethyl) triazine derivatives 2-[2-(4-methoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-l,3,5-triazine(TZ1), 2-[2-(3,4-dimethoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-1,3,5-triazine(TZ2) and 2-(1,3-benzodioxol-5-yl)-4,6-bis(trichloromethyl)-1,3,5-triazine(TZ3) were synthesized and studied in this work. In the acid measurement, the acid-forming performance of S-triazinyl derivatives was evaluated by the method ascertained in our laboratory. The results indicate that the novel triazine has the better acid-forming performance that subsequently catalyzes the deblocking of a protecting group in copolymers. 展开更多
关键词 TRIAZINE Photo-acid generator Photo-sensitizer Acid production efficiency
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Efficient Slew-Rate Enhanced Operational Transconductance Amplifier
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作者 Xiao-Peng Wan Fei-Xiang Zhang +2 位作者 Shao-Wei Zhen Ya-Juan He Ping Luo 《Journal of Electronic Science and Technology》 CAS CSCD 2015年第1期14-19,共6页
Today, along with the prevalent use of portable equipment, wireless, and other battery powered systems, the demand for amplifiers with a high gain-bandwidth product(GBW), slew rate(SR), and at the same time very l... Today, along with the prevalent use of portable equipment, wireless, and other battery powered systems, the demand for amplifiers with a high gain-bandwidth product(GBW), slew rate(SR), and at the same time very low static power dissipation is growing. In this work, an operational transconductance amplifier(OTA) with an enhanced SR is proposed. By inserting a sensing resistor in the input port of the current mirror in the OTA, the voltage drop across the resistor is converted into an output current containing a term in proportion to the square of the voltage, and then the SR of the proposed OTA is significantly enhanced and the current dissipation can be reduced. The proposed OTA is designed and simulated with a 0.5μm complementary metal oxide semiconductor(CMOS) process. The simulation results show that the SR is 4.54V/μs, increased by 8.25 times than that of the conventional design, while the current dissipation is only 87.3%. 展开更多
关键词 Efficient gain-bandwidth product operational transconductance amplifier slew rate
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Combustion characteristics of low-quality lignite for different bed material sphericities in a circulating fluidized bed boiler:A numerical study
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作者 BarışGürel Gülşah Karaca Dolgun +1 位作者 Osmanİpek Ali Keçebaş 《Particuology》 SCIE EI CAS CSCD 2024年第7期364-382,共19页
This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).U... This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified through experimentation,the research reveals several key findings.Notably,furnace temperatures tended to rise with higher sphericity ratios,albeit with variations between lignite types,particularly highlighting the complexity of this relationship in the case of GLI-Tunçbilek lignite.Pressure levels in the combustion chamber remained consistent across different sphericity ratios,indicating minimal influence on pressure dynamics.Improved combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lignite,as reflected in CO_(2) mole fractions.While NO_(x) emissions generally decreased with lower sphericity,the sensitivity to sphericity varied by lignite type,with Ilgın lignite showcasing low NO_(x) but high SO_(2) emissions,underscoring the intricate interplay between lignite properties,sphericity,and emissions.Overall,this study advances our understanding of CFBB combustion dynamics,offering insights valuable for optimizing performance and emissions control,particularly in lignite-based power. 展开更多
关键词 Circulating fluidized bed boiler Computational particle fluid dynamics method Particle sphericity ratios NO_(x)and SO_(2)emissions Energy production efficiency
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A data envelopment analysis of agricultural technical efficiency of Northwest Arid Areas in China 被引量:3
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作者 Yubao WANG Lijie SHI +1 位作者 Haojie ZHANG Shikun SUN 《Frontiers of Agricultural Science and Engineering》 2017年第2期195-207,共13页
Severe resource shortage and waste of resource in agricultural production make it necessary to assess efficiency to increase productivity with high efficiency and ensure sustainable agricultural development. This pape... Severe resource shortage and waste of resource in agricultural production make it necessary to assess efficiency to increase productivity with high efficiency and ensure sustainable agricultural development. This paper adopted an input-oriented data envelopment analysis(DEA) method with the assumption of variable returns to scale to evaluate agricultural production efficiency of 100 major irrigation districts in Northwest China in 2010.Major findings of this paper were as follows: firstly, the average value of total technical efficiency, pure technical efficiency and scale efficiency of those irrigation districts in Northwest China were 0.770, 0.825 and 0.931,respectively; secondly, 30% of irrigation districts were technically efficient, while 42% and 32% of them showed pure technical and scale efficiency respectively. Among inefficient decision-making units, total technical efficiency score varied from 0.313 to 0.966, showing significant geographical differences, but geographical differences of pure technical efficiency was more consistent with that of total technical efficiency; thirdly, input redundancy was evident. Inputs of agricultural population, irrigation area,green water, blue water, consumption of fertilizer and agricultural machinery could be reduced by 34.88%,40.19%, 43.85%, 47.10%, 41.53% and 42.21% respectively without reducing agricultural outputs. Furthermore,irrigation area, green water and blue water had relatively high slack movement though Northwest China which is short of water resources. Based on these results, this paper drew the following conclusions: First, there is huge potential for Northwest China to improve its agricultural production efficiency, and agro-technology not input scale had greater influence on improvement. Second, farmers needed proper guidance in order to reduce agricultural inputs and it is time to centralize agricultural management for overall agricultural inputs regulation and control. 展开更多
关键词 agricultural production efficiency DEA model input redundancy irrigation districts Northwest Arid Areas in China
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Does Security of Land Operational Rights Matter for the Improvement of Agricultural Production Efficiency under the Collective Ownership in China? 被引量:2
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作者 Xianqing Ji Shouying Liu +1 位作者 Jianan Yan Youyi Li 《China & World Economy》 SCIE 2021年第1期87-108,共22页
Under the"separation of three rights"policy,the impact of security of land operationalrights on agricultural production efficiency has attracted much attention in recentyears.Data envelopment analysis and me... Under the"separation of three rights"policy,the impact of security of land operationalrights on agricultural production efficiency has attracted much attention in recentyears.Data envelopment analysis and mediation effect analysis were applied to 888family farms run by new-type agricultural operators from Songjiang to identify themechanism of the effect of land operational rights security on agricultural productionefficiency through long-term investment.The results show that greater security of landoperational rights generally increased agricultural production efficiency.Approximately37.94 percent of the impact could be explained by long-term investment.The resultsalso indicate that significant heterogeneity exists in the effect of land operational rightssecurity on agricultural production efficiency at various levels of the family farms'efficiency distributions.lt is suggested that government should legalize land operationalrights and give them a status equal to those of households'contractual rights and landownership rights in China's future land tenure reform. 展开更多
关键词 agricultural production efficiency new-type agricultural operator security of land operational rights
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An approach to optimize the batch mixing process for improving the quality consistency of the products made from traditional Chinese medicines 被引量:2
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作者 Bin-jun YAN Hai-bin QU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第11期1041-1048,共8页
The efficacy of traditional Chinese medicine(TCM)is based on the combined effects of its constituents.Variation in chemical composition between batches of TCM has always been the deterring factor in achieving consiste... The efficacy of traditional Chinese medicine(TCM)is based on the combined effects of its constituents.Variation in chemical composition between batches of TCM has always been the deterring factor in achieving consistency in efficacy.The batch mixing process can significantly reduce the batch-to-batch quality variation in TCM extracts by mixing them in a well-designed proportion.However,reducing the quality variation without sacrificing too much of the production efficiency is one of the challenges.Accordingly,an innovative and practical batch mixing method aimed at providing acceptable efficiency for industrial production of TCM products is proposed in this work,which uses a minimum number of batches of extracts to meet the content limits.The important factors affecting the utilization ratio of the extracts(URE)were studied by simulations.The results have shown that URE was affected by the correlation between the contents of constituents,and URE decreased with the increase in the number of targets and the relative standard deviations of the contents.URE could be increased by increasing the number of storage tanks.The results have provided a reference for designing the batch mixing process.The proposed method has possible application value in reducing the quality variation in TCM and providing acceptable production efficiency simultaneously. 展开更多
关键词 Batch-to-batch quality consistency Batch mixing Production efficiency Traditional Chinese medicine
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