This paper uses the ecological footprint model to make comparison of the eco-efficiency of arable land ecological footprint in different years in Hubei Province, and makes comparison of that in Hubei and some countrie...This paper uses the ecological footprint model to make comparison of the eco-efficiency of arable land ecological footprint in different years in Hubei Province, and makes comparison of that in Hubei and some countries. The results indicate that, since 1965, the eco-efficiency of arable land ecological footprint in Hubei has been improved year by year. However, the efficiency of arable land ecological footprint, compared with some other areas in the world, is much lower. In 1965, average eco-efficiency of world arable land ecological footprint is 3 421 US dollar/hm^2 while that of Hubei Province is 134 US dollar/hm^2, about 1/26 of the world＇s average level. The eco-efficiency of arable land ecological footprint for 2003 in Hubei Province, however, has become about 1/9 of the world＇s average level for the same year. Finally the author puts forward the ways to raise the eco-efficiency of arable land ecological footprint.展开更多
Urban agglomerations in China have become the strategic core of national economic development and the main component of the new type of urbanization. However, they are threatened by a series of eco-environmental probl...Urban agglomerations in China have become the strategic core of national economic development and the main component of the new type of urbanization. However, they are threatened by a series of eco-environmental problems and challenges, including the severe overexploitation of natural resources. Eco-efficiency, which is defined as accomplishing the greatest possible economic benefit with the least possible resource input and damage to the environment, is used as an indicator to quantify the sustainability of urban agglomerations. In this work, a traditional data envelopment analysis(DEA) model with a slack-based measurement(SBM) model of undesirable outputs, was used to assess and compare the economic efficiency and eco-efficiency of four major urban agglomerations in eastern China(UAECs) in 2005, 2011, and 2014. The spatio-temporal characteristics of the evolution of urban agglomerations were analyzed. Based on the results of a slack analysis, suggestions for improving the eco-efficiency of the four UAECs are provided. The overall economic efficiency of urban agglomerations located in the Shandong Peninsula, Yangtze River Delta, and Pearl River Delta displayed a V-shaped pattern(decreased and then increased). In contrast, the overall economic efficiency of the Beijing-Tianjin-Hebei urban agglomeration declined during the study period. The Beijing-Tianjin-Hebei urban agglomeration had a considerable loss of economic efficiency due to pollution, whereas the Shandong Peninsula urban agglomeration was less impacted. Overall, the eco-environmental efficiency of the four UAECs declined from 2005 to 2011 and then increased from 2011 to 2014. In addition, the urban eco-efficiency in the four coastal UAECs was characterized by different evolution patterns. The eco-efficiency was higher in the peri-urban areas of the core cities, riverside areas, and seaside areas and lower in the inland cities. The core cities of the Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta urban agglomerations were characterized by high resource consumption, economic benefit output, and eco-efficiency. In most of cities in the urban agglomerations, the emission of pollutants declined, leading to a reduction of pollutants and mitigation of environmental problems. In addition, a differential analysis, from the perspective of urban agglomeration, was performed, and concrete suggestions for improvement are proposed.展开更多
Energy eco-efficiency is a concept integrating ecological and economic benefits arising from energy utilization and serves as a measure of efficiency in the energy-environment-economy system. Using the slacks-based me...Energy eco-efficiency is a concept integrating ecological and economic benefits arising from energy utilization and serves as a measure of efficiency in the energy-environment-economy system. Using the slacks-based measure （SBM） model considering undesirable output, this study first measures the energy eco-efficiency of provinces in China from 1997 to 2012. It then analyzes the spatial distribution and evolution of energy eco-efficiency from three aspects： scale, intensity, and grain of spatial patterns. Finally, it examines the spatial spillover effects and influencing factors of energy eco-efficiency in different provinces by means of a spatial econometric model. The following conclusions are drawn： （1） The overall energy ecofficiency is relatively low in China, with energy-inefficient regions accounting for about 40%. Guangdong, Hainan and Fujian provinces enjoy the highest energy eco-efficiency, while Ningxia, Gansu, Qinghai, and Xinjiang are repre- sentative regions with low efficiency. Thus, the pattern of evolution of China＇s overall energy eco-efficiency is U-shaped. Among local regions, four main patterns of evolution are found： increasing, fluctuating, mutating, and leveling. （2） At the provincial level, China＇s energy eco-efficiency features significant spatial agglomeration both globally and locally. High-high agglomeration occurs mainly in the eastern and southern coastal regions and low-low agglomeration in the northwestern region and the middle reaches of the Yellow River. Changes in spatial patterns have occurred mainly in areas with high-low and low-high agglomeration, with the most remarkable change taking place in the Beijing-Tianjin-Hebei region. （3） There exist significant spatial effects of energy eco-efficiency among provinces in China. For the energy eco-efficiency of a given region spatial spillovers from adjacent regions outweigh the influence of errors in adjacent regions. Industrial structure has the greatest influence on energy eco-efficiency.展开更多
According to the eco-efficiency theory, combined with agricultural production characteristics, I point out the environmental impact and substance energy consumption characteristics of agricultural production. Based on...According to the eco-efficiency theory, combined with agricultural production characteristics, I point out the environmental impact and substance energy consumption characteristics of agricultural production. Based on this, I establish the eco-efficiency evaluation indicator system for agricultural production, and conduct a comprehensive analysis on the agricultural eco-efficiency of 17 prefecture-level cities in Anhui Province, using data envelopment analysis method.展开更多
In order to improve the agricultural eco-efficiency and promote the sustainable development of agriculture in Henan Province, China, based on the footprint theory, the super-efficiency SBM model </span></span...In order to improve the agricultural eco-efficiency and promote the sustainable development of agriculture in Henan Province, China, based on the footprint theory, the super-efficiency SBM model </span></span><span><span><span style="font-family:"">is</span></span></span><span><span><span style="font-family:""> used to scientifically calculate and analyze the agricultural eco-efficiency in Henan Province. On this basis, the influencing factors of agricultural eco-efficiency in Henan Province are quantitatively analyzed by using the grey incidence analysis model. The <span>results s</span><span>how that unilaterally considering one of grey water footprint</span></span></span></span><span><span><span style="font-family:"">s</span></span></span><span><span><span style="font-family:""> and carbon footprint</span></span></span><span><span><span style="font-family:"">s</span></span></span><span><span><span style="font-family:""> will overestimate or underestimate the agricultural eco-efficiency of Henan Province in different degrees in different time periods, and the agricultural eco-efficiency obtained by comprehensively considering grey water footprint and carbon footprint (GWCAEE) is more in line with the reality of agricultural development in Henan Province. In 2000-2004, GWCAEE in Henan Province was better. During 2005-2014, GWCAEE in Henan Province showed a fluctuating decline and continued to be in an inefficient state. From 2015</span></span></span><span><span><span style="font-family:""> to 2019, GWCAEE of Henan Province gradually increased, and it became effective in 2019. In recent years, GWCAEE has developed well. Through the grey incidence analysis between 12 influencing factors including endogenous factors and exogenous factors and GWCAEE, it is found that the six leading factors of GWCAEE in Henan Province are agricultural structure, financial input for agriculture, number of agricultural employees, crop sown area, consumption of chemical pesticide, consumption of agricultural diesel oil. According to the above research conclusions, suggestions for improving agricultural eco-efficiency in Henan Province are put forward.展开更多
Aim To determine efficiency of multi-range hydro-mechanical stepless transmis- sion(HMT).Methods Ageneral model of HMT was of HMT was structured.On the basis of power flow analysis, the efficiency was obtained,Results...Aim To determine efficiency of multi-range hydro-mechanical stepless transmis- sion(HMT).Methods Ageneral model of HMT was of HMT was structured.On the basis of power flow analysis, the efficiency was obtained,Results efficiency of multi-range HMT changes continuously with output speed in speed range and is higher than the highest point of the hydraulic efficiency,The volumetric efficiency can potentially result in the speed fluctuation, which can be reduced or eliminated through controlling the ratio of the displacements ofhydraulic unity properly or changing the point of range exchanging .And the mechanical- constant output torque or different output torque under the condition of constant pressure when the transmission works in different parts of a range,Conclusion The multi-range HMT is an ideal stepless transmission with high efficiency.展开更多
Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yiel...Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation.展开更多
The problem of municipal solid waste (MSW) management has been an issue of global concern in recent times and has engaged governments and local authorities in their quest to manage solid waste in a sustained manner. O...The problem of municipal solid waste (MSW) management has been an issue of global concern in recent times and has engaged governments and local authorities in their quest to manage solid waste in a sustained manner. One proposition which has the potential of solving three problems at the same time is the use of the biodegradable component of MSW as a source of energy to augment energy supply. This research therefore assessed the use of the organic fraction of MSW as an eco-efficient energy source in Ghana. A study of Ghana’s solid waste profile was undertaken and the fraction of biodegradable component was found to be approximately 60%, with a heating value of 17 MJ/kg and a moisture content of 50%. Moreover, it was established that 0.5 kg of solid waste is generated daily by each Ghanaian, meaning that about 5610 tons of the organic fraction could be made available every day to generate energy to the national grid. It was also established that waste disposal in Ghana is largely by way of open dumping as primary collection of waste from households in Ghana is limited to high-income communities which represent only 11% of the population, whereas secondary collection from transfer points to the disposal facilities is inefficient. With representative power output of 1.66 MWh/tonne a total of 3320 GWh of energy can be produced annually from the 4 proposed plants, generating net revenue of about $111,600,000. As an optimizing step, a waste incineration scheme was suggested in which the off-gases produced from organic waste combustion could be used to produce electrical power with steam in a multi-stage heat exchanger-steam turbine configuration, and the off gases again used for pre-drying of the organic waste in a cycle. A state-of-the art waste incineration technology was used as a model and adapted to suit Ghana’s tropical conditions. MSW combustion releases less CO2 for the same power output (837 Ib/MWh) than any of the other conventional fuels do, and is therefore a good fuel for the fight against climate change.展开更多
Nowadays,Hubei Province pays more attention to sustainable development with the purpose of building green province. Therefore,in the construction process of ecological civilization in Hubei Province,how to get the opt...Nowadays,Hubei Province pays more attention to sustainable development with the purpose of building green province. Therefore,in the construction process of ecological civilization in Hubei Province,how to get the optimal economic output with minimum resource consumption and minor environment damage is one of the most urgent problems. Based on the panel data of 12 prefecture-level cities in Hubei Province from 2005 to 2014,the Malmquist Productivity Index( MPI) was used to calculate the eco-efficiency of 12 prefecture-level cities in Hubei Province. According to the analyzed results,it was found that there was a downward trend of ecological efficiency in Hubei Province during the study period. As for the overall environmental production situation of the whole province in this period,results showed that environmental production efficiency was improved while the level of environmental production technology has decreased greatly. This phenomenon maybe result from different speed,because the speed of technical efficiency improvement was less than the extent of technology decline,which finally led that the Hubei Province's environmental productivity declined.展开更多
Evaluating real world situations in risky environments based on various qualitative/quantitative criteria in order to suggest a strategy/policy among available options is one of the critical challenges in inciden...Evaluating real world situations in risky environments based on various qualitative/quantitative criteria in order to suggest a strategy/policy among available options is one of the critical challenges in incident management. Such is the case when considering an eco-efficient development strategy that can minimize the risk associated with the location of gas stations in human settlements. Taking the Douala city of Cameroon as an example, four actions were evaluated, including the options of relocating the gas stations, putting in place of emergency response plan in gas stations, and relocation of households subject to a group of four criteria. Data were collected via personal communication with decision-makers using a five-point Likert scale. The market values of buildings subject to expropriation were estimated based on order No. 0082/Y. 15.1/MNUH/D of 20 November 1987 of the ministry of Housing and Urban Development, Cameroon. The financial costs incurred in establishing a gas station were an average value obtained from a sample of 80 gas stations randomly selected among those whose locations do not comply with existing regulations. These amounts were obtained from their financial records, while the value of putting in place an emergency action plan was obtained from the current market value of the equipment required. The algorithm of PROMETHEE under the usual criterion function was implemented. The results suggested that putting in place an emergency response plan could minimize relocation costs, maximize profits/welfare, and maximize environmental quality, and minimize social impacts, and was therefore considered as the most preferred alternative. Sensitivity analyses of results further confirmed that implementation of emergency response plan is the most preferred alternative.展开更多
A research team led by Dr.GE Ziyi from the Ningbo Institute of Materials Technology and Engineering(NIMTE)of the Chinese Academy of Sciences has developed novel giant acceptors with an oxygenated linker,enabling the c...A research team led by Dr.GE Ziyi from the Ningbo Institute of Materials Technology and Engineering(NIMTE)of the Chinese Academy of Sciences has developed novel giant acceptors with an oxygenated linker,enabling the creation of highly efficient non-halogen-processed organic solar cells(OSCs),with a power conversion efficiency(PCE)up to 20.02%.展开更多
Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from ...Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from low efficiencies.In this article,we report a tractable approach to modifying g-C3N4 with vanadyl phthalocyanine(VOPc/CN)for efficient visible-light-driven hydrogen production.A non-covalent VOPc/CN hybrid photocatalyst formed viaπ-πstacking interactions between the two components,as confirmed by analysis of UV-vis absorption spectra.The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability.Under optimal conditions,the corresponding H2 evolution rate is nearly 6 times higher than that of pure g-C3N4.The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively.It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C3N4-based hybrid systems with strong light absorption and high-efficiency carrier separation.展开更多
A highly efficient and convenient procedure for the enantioselective synthesis of (S)-Rivastigmine, a cholinergic agent for the treatment of mild to moderate dementia of the Alzheimer’s type and dementia due to Parki...A highly efficient and convenient procedure for the enantioselective synthesis of (S)-Rivastigmine, a cholinergic agent for the treatment of mild to moderate dementia of the Alzheimer’s type and dementia due to Parkinson’s disease, is accomplished by the treatment of versatile, readily accessible (S)-(-)-2-methyl-2-propanesulfinamide with 3-hydroxyacetophenone. This protocol provides high yield and excellent enantiomeric excess in short step synthesis.展开更多
Increasing complexity of distributed hydrological model （DHM） has lowered the efficiency of convergence.In this study,global sensitivity analysis （SA） was introduced by combining multiobjective （MO） optimization...Increasing complexity of distributed hydrological model （DHM） has lowered the efficiency of convergence.In this study,global sensitivity analysis （SA） was introduced by combining multiobjective （MO） optimization for DHM calibration.Latin Hypercube-once at a time （LH-OAT） was adopted in global parameter SA to obtain relative sensitivity of model parameter,which can be categorized into different sensitivity levels.Two comparative study cases were conducted to present the efficiency and feasibility by combining SA with MO（SA-MO）.WetSpa model with non-dominated sorting genetic algorithm-Ⅱ （NSGA-Ⅱ） algorithm and EasyDHM model with multi-objective sequential complex evolutionary metropolis-uncertainty analysis （MOSCEM-UA）algorithm were adopted to demonstrate the general feasibility of combining SA in optimization.Results showed that the LH-OAT was globally effective in selecting high sensitivity parameters.It proves that using parameter from high sensitivity groups results in higher convergence efficiency.Study case Ⅰ showed a better Pareto front distribution and convergence compared with model calibration without SA.Study case Ⅱ indicated a more efficient convergence of parameters in sequential evolution of MOSCEM-UA under the same iteration.It indicates that SA-MO is feasible and efficient for high dimensional DHM calibration.展开更多
The Chinese economy has been experiencing extensive growth for decades. Along with this growth, however, there have been industrial-economic, social and environmental inefficiencies. In some regions, problems exist be...The Chinese economy has been experiencing extensive growth for decades. Along with this growth, however, there have been industrial-economic, social and environmental inefficiencies. In some regions, problems exist because of overemphasis on GDP growth, or growth at the expense of the environment. Looking at efficiency through the prism of economic, social and environmental factors, this article analyzes the industrial economic development during the 10th Five-Year Plan (2001-2005). The authors conclude that economic development should be achieved while making overall improvements to economic, social and ecoenvironment efficiency.展开更多
The life-cycle eco-footprint computing model of building projects was established in the study. It contained the eco-footprint in 4 aspects during the lifecycle: consumed energy, consumed resource, emitted carbon diox...The life-cycle eco-footprint computing model of building projects was established in the study. It contained the eco-footprint in 4 aspects during the lifecycle: consumed energy, consumed resource, emitted carbon dioxide and produced solid waste. Space efficiency of life-cycle eco-footprint index was proposed and used to assess the eco-sustainability of building projects. Then, the eco-footprint and ecosustainability of 4 different structure types(brick-concrete bungalow, multi-storey brick-concrete, multistorey steel-concrete, high-rise steel-concrete) for residential building in severely cold areas were investigated. The results indicated that: 1) Compared with bungalow, high-rise building with relatively smaller shape coefficient and window-wall ratio had higher eco-sustainability; 2) For the buildings with the same storey, shape coefficient and window-wall ratio, steel-concrete building had higher eco-sustainability than brickconcrete building; 3) High-rise steel-concrete structure had the greatest eco-sustainability during the 4 different bui lding structures, so it was more suitable to promote.展开更多
In the paper entitled"Efficient adsorption of Mn(Ⅱ)by layered double hydroxides intercalated with di ethylenetriaminepentaacetic acid and the mechanistic study"in Journal of Environmental Sciences,volume 85...In the paper entitled"Efficient adsorption of Mn(Ⅱ)by layered double hydroxides intercalated with di ethylenetriaminepentaacetic acid and the mechanistic study"in Journal of Environmental Sciences,volume 85,page 56-65,there were problems with mathematical notation and dimensional errors in the calculation for Giibbs free energy.In Section 2.5:Adsorption isotherms and thermodynamics studies,authors calculated the Gibbs free energy change(△G°)展开更多
文摘This paper uses the ecological footprint model to make comparison of the eco-efficiency of arable land ecological footprint in different years in Hubei Province, and makes comparison of that in Hubei and some countries. The results indicate that, since 1965, the eco-efficiency of arable land ecological footprint in Hubei has been improved year by year. However, the efficiency of arable land ecological footprint, compared with some other areas in the world, is much lower. In 1965, average eco-efficiency of world arable land ecological footprint is 3 421 US dollar/hm^2 while that of Hubei Province is 134 US dollar/hm^2, about 1/26 of the world＇s average level. The eco-efficiency of arable land ecological footprint for 2003 in Hubei Province, however, has become about 1/9 of the world＇s average level for the same year. Finally the author puts forward the ways to raise the eco-efficiency of arable land ecological footprint.
基金Major Program of National Natural Science Foundation of China,No.41590840,No.41590842National Natural Science Foundation of China,No.41371177
文摘Urban agglomerations in China have become the strategic core of national economic development and the main component of the new type of urbanization. However, they are threatened by a series of eco-environmental problems and challenges, including the severe overexploitation of natural resources. Eco-efficiency, which is defined as accomplishing the greatest possible economic benefit with the least possible resource input and damage to the environment, is used as an indicator to quantify the sustainability of urban agglomerations. In this work, a traditional data envelopment analysis(DEA) model with a slack-based measurement(SBM) model of undesirable outputs, was used to assess and compare the economic efficiency and eco-efficiency of four major urban agglomerations in eastern China(UAECs) in 2005, 2011, and 2014. The spatio-temporal characteristics of the evolution of urban agglomerations were analyzed. Based on the results of a slack analysis, suggestions for improving the eco-efficiency of the four UAECs are provided. The overall economic efficiency of urban agglomerations located in the Shandong Peninsula, Yangtze River Delta, and Pearl River Delta displayed a V-shaped pattern(decreased and then increased). In contrast, the overall economic efficiency of the Beijing-Tianjin-Hebei urban agglomeration declined during the study period. The Beijing-Tianjin-Hebei urban agglomeration had a considerable loss of economic efficiency due to pollution, whereas the Shandong Peninsula urban agglomeration was less impacted. Overall, the eco-environmental efficiency of the four UAECs declined from 2005 to 2011 and then increased from 2011 to 2014. In addition, the urban eco-efficiency in the four coastal UAECs was characterized by different evolution patterns. The eco-efficiency was higher in the peri-urban areas of the core cities, riverside areas, and seaside areas and lower in the inland cities. The core cities of the Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta urban agglomerations were characterized by high resource consumption, economic benefit output, and eco-efficiency. In most of cities in the urban agglomerations, the emission of pollutants declined, leading to a reduction of pollutants and mitigation of environmental problems. In addition, a differential analysis, from the perspective of urban agglomeration, was performed, and concrete suggestions for improvement are proposed.
文摘Energy eco-efficiency is a concept integrating ecological and economic benefits arising from energy utilization and serves as a measure of efficiency in the energy-environment-economy system. Using the slacks-based measure （SBM） model considering undesirable output, this study first measures the energy eco-efficiency of provinces in China from 1997 to 2012. It then analyzes the spatial distribution and evolution of energy eco-efficiency from three aspects： scale, intensity, and grain of spatial patterns. Finally, it examines the spatial spillover effects and influencing factors of energy eco-efficiency in different provinces by means of a spatial econometric model. The following conclusions are drawn： （1） The overall energy ecofficiency is relatively low in China, with energy-inefficient regions accounting for about 40%. Guangdong, Hainan and Fujian provinces enjoy the highest energy eco-efficiency, while Ningxia, Gansu, Qinghai, and Xinjiang are repre- sentative regions with low efficiency. Thus, the pattern of evolution of China＇s overall energy eco-efficiency is U-shaped. Among local regions, four main patterns of evolution are found： increasing, fluctuating, mutating, and leveling. （2） At the provincial level, China＇s energy eco-efficiency features significant spatial agglomeration both globally and locally. High-high agglomeration occurs mainly in the eastern and southern coastal regions and low-low agglomeration in the northwestern region and the middle reaches of the Yellow River. Changes in spatial patterns have occurred mainly in areas with high-low and low-high agglomeration, with the most remarkable change taking place in the Beijing-Tianjin-Hebei region. （3） There exist significant spatial effects of energy eco-efficiency among provinces in China. For the energy eco-efficiency of a given region spatial spillovers from adjacent regions outweigh the influence of errors in adjacent regions. Industrial structure has the greatest influence on energy eco-efficiency.
基金Supported by Special Project for Youth Research in Anhui Institute of Architecture&Industry(20104012)
文摘According to the eco-efficiency theory, combined with agricultural production characteristics, I point out the environmental impact and substance energy consumption characteristics of agricultural production. Based on this, I establish the eco-efficiency evaluation indicator system for agricultural production, and conduct a comprehensive analysis on the agricultural eco-efficiency of 17 prefecture-level cities in Anhui Province, using data envelopment analysis method.
文摘In order to improve the agricultural eco-efficiency and promote the sustainable development of agriculture in Henan Province, China, based on the footprint theory, the super-efficiency SBM model </span></span><span><span><span style="font-family:"">is</span></span></span><span><span><span style="font-family:""> used to scientifically calculate and analyze the agricultural eco-efficiency in Henan Province. On this basis, the influencing factors of agricultural eco-efficiency in Henan Province are quantitatively analyzed by using the grey incidence analysis model. The <span>results s</span><span>how that unilaterally considering one of grey water footprint</span></span></span></span><span><span><span style="font-family:"">s</span></span></span><span><span><span style="font-family:""> and carbon footprint</span></span></span><span><span><span style="font-family:"">s</span></span></span><span><span><span style="font-family:""> will overestimate or underestimate the agricultural eco-efficiency of Henan Province in different degrees in different time periods, and the agricultural eco-efficiency obtained by comprehensively considering grey water footprint and carbon footprint (GWCAEE) is more in line with the reality of agricultural development in Henan Province. In 2000-2004, GWCAEE in Henan Province was better. During 2005-2014, GWCAEE in Henan Province showed a fluctuating decline and continued to be in an inefficient state. From 2015</span></span></span><span><span><span style="font-family:""> to 2019, GWCAEE of Henan Province gradually increased, and it became effective in 2019. In recent years, GWCAEE has developed well. Through the grey incidence analysis between 12 influencing factors including endogenous factors and exogenous factors and GWCAEE, it is found that the six leading factors of GWCAEE in Henan Province are agricultural structure, financial input for agriculture, number of agricultural employees, crop sown area, consumption of chemical pesticide, consumption of agricultural diesel oil. According to the above research conclusions, suggestions for improving agricultural eco-efficiency in Henan Province are put forward.
文摘Aim To determine efficiency of multi-range hydro-mechanical stepless transmis- sion(HMT).Methods Ageneral model of HMT was of HMT was structured.On the basis of power flow analysis, the efficiency was obtained,Results efficiency of multi-range HMT changes continuously with output speed in speed range and is higher than the highest point of the hydraulic efficiency,The volumetric efficiency can potentially result in the speed fluctuation, which can be reduced or eliminated through controlling the ratio of the displacements ofhydraulic unity properly or changing the point of range exchanging .And the mechanical- constant output torque or different output torque under the condition of constant pressure when the transmission works in different parts of a range,Conclusion The multi-range HMT is an ideal stepless transmission with high efficiency.
基金research support from the National Key Research and Development Program of China (2016YFD0300110, 2016YFD0300101)the National Basic Research Program of China (2015CB150401)+2 种基金the National Natural Science Foundation of China (31360302)the Science and Technology Program of the Sixth Division of Xinjiang Construction Corps in China (1703)the Agricultural Science and Technology Innovation Program for financial support.
文摘Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation.
文摘The problem of municipal solid waste (MSW) management has been an issue of global concern in recent times and has engaged governments and local authorities in their quest to manage solid waste in a sustained manner. One proposition which has the potential of solving three problems at the same time is the use of the biodegradable component of MSW as a source of energy to augment energy supply. This research therefore assessed the use of the organic fraction of MSW as an eco-efficient energy source in Ghana. A study of Ghana’s solid waste profile was undertaken and the fraction of biodegradable component was found to be approximately 60%, with a heating value of 17 MJ/kg and a moisture content of 50%. Moreover, it was established that 0.5 kg of solid waste is generated daily by each Ghanaian, meaning that about 5610 tons of the organic fraction could be made available every day to generate energy to the national grid. It was also established that waste disposal in Ghana is largely by way of open dumping as primary collection of waste from households in Ghana is limited to high-income communities which represent only 11% of the population, whereas secondary collection from transfer points to the disposal facilities is inefficient. With representative power output of 1.66 MWh/tonne a total of 3320 GWh of energy can be produced annually from the 4 proposed plants, generating net revenue of about $111,600,000. As an optimizing step, a waste incineration scheme was suggested in which the off-gases produced from organic waste combustion could be used to produce electrical power with steam in a multi-stage heat exchanger-steam turbine configuration, and the off gases again used for pre-drying of the organic waste in a cycle. A state-of-the art waste incineration technology was used as a model and adapted to suit Ghana’s tropical conditions. MSW combustion releases less CO2 for the same power output (837 Ib/MWh) than any of the other conventional fuels do, and is therefore a good fuel for the fight against climate change.
文摘Nowadays,Hubei Province pays more attention to sustainable development with the purpose of building green province. Therefore,in the construction process of ecological civilization in Hubei Province,how to get the optimal economic output with minimum resource consumption and minor environment damage is one of the most urgent problems. Based on the panel data of 12 prefecture-level cities in Hubei Province from 2005 to 2014,the Malmquist Productivity Index( MPI) was used to calculate the eco-efficiency of 12 prefecture-level cities in Hubei Province. According to the analyzed results,it was found that there was a downward trend of ecological efficiency in Hubei Province during the study period. As for the overall environmental production situation of the whole province in this period,results showed that environmental production efficiency was improved while the level of environmental production technology has decreased greatly. This phenomenon maybe result from different speed,because the speed of technical efficiency improvement was less than the extent of technology decline,which finally led that the Hubei Province's environmental productivity declined.
文摘Evaluating real world situations in risky environments based on various qualitative/quantitative criteria in order to suggest a strategy/policy among available options is one of the critical challenges in incident management. Such is the case when considering an eco-efficient development strategy that can minimize the risk associated with the location of gas stations in human settlements. Taking the Douala city of Cameroon as an example, four actions were evaluated, including the options of relocating the gas stations, putting in place of emergency response plan in gas stations, and relocation of households subject to a group of four criteria. Data were collected via personal communication with decision-makers using a five-point Likert scale. The market values of buildings subject to expropriation were estimated based on order No. 0082/Y. 15.1/MNUH/D of 20 November 1987 of the ministry of Housing and Urban Development, Cameroon. The financial costs incurred in establishing a gas station were an average value obtained from a sample of 80 gas stations randomly selected among those whose locations do not comply with existing regulations. These amounts were obtained from their financial records, while the value of putting in place an emergency action plan was obtained from the current market value of the equipment required. The algorithm of PROMETHEE under the usual criterion function was implemented. The results suggested that putting in place an emergency response plan could minimize relocation costs, maximize profits/welfare, and maximize environmental quality, and minimize social impacts, and was therefore considered as the most preferred alternative. Sensitivity analyses of results further confirmed that implementation of emergency response plan is the most preferred alternative.
文摘A research team led by Dr.GE Ziyi from the Ningbo Institute of Materials Technology and Engineering(NIMTE)of the Chinese Academy of Sciences has developed novel giant acceptors with an oxygenated linker,enabling the creation of highly efficient non-halogen-processed organic solar cells(OSCs),with a power conversion efficiency(PCE)up to 20.02%.
基金supported by the National Natural Science Foundation of China(51572253,21771171)Scientific Research Grant of Hefei National Synchrotron Radiation Laboratory(UN2017LHJJ)+1 种基金the Fundamental Research Funds for the Central Universitiescooperation between NSFC and Netherlands Organization for Scientific Research(51561135011)~~
文摘Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from low efficiencies.In this article,we report a tractable approach to modifying g-C3N4 with vanadyl phthalocyanine(VOPc/CN)for efficient visible-light-driven hydrogen production.A non-covalent VOPc/CN hybrid photocatalyst formed viaπ-πstacking interactions between the two components,as confirmed by analysis of UV-vis absorption spectra.The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability.Under optimal conditions,the corresponding H2 evolution rate is nearly 6 times higher than that of pure g-C3N4.The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively.It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C3N4-based hybrid systems with strong light absorption and high-efficiency carrier separation.
文摘A highly efficient and convenient procedure for the enantioselective synthesis of (S)-Rivastigmine, a cholinergic agent for the treatment of mild to moderate dementia of the Alzheimer’s type and dementia due to Parkinson’s disease, is accomplished by the treatment of versatile, readily accessible (S)-(-)-2-methyl-2-propanesulfinamide with 3-hydroxyacetophenone. This protocol provides high yield and excellent enantiomeric excess in short step synthesis.
基金National Basic Research Program(973)of China(No.2010CB951102)Innovative Research Groups of the National Natural Science Foundation,China(No.51021006)National Natural Science Foundation of China(No.51079028)
文摘Increasing complexity of distributed hydrological model （DHM） has lowered the efficiency of convergence.In this study,global sensitivity analysis （SA） was introduced by combining multiobjective （MO） optimization for DHM calibration.Latin Hypercube-once at a time （LH-OAT） was adopted in global parameter SA to obtain relative sensitivity of model parameter,which can be categorized into different sensitivity levels.Two comparative study cases were conducted to present the efficiency and feasibility by combining SA with MO（SA-MO）.WetSpa model with non-dominated sorting genetic algorithm-Ⅱ （NSGA-Ⅱ） algorithm and EasyDHM model with multi-objective sequential complex evolutionary metropolis-uncertainty analysis （MOSCEM-UA）algorithm were adopted to demonstrate the general feasibility of combining SA in optimization.Results showed that the LH-OAT was globally effective in selecting high sensitivity parameters.It proves that using parameter from high sensitivity groups results in higher convergence efficiency.Study case Ⅰ showed a better Pareto front distribution and convergence compared with model calibration without SA.Study case Ⅱ indicated a more efficient convergence of parameters in sequential evolution of MOSCEM-UA under the same iteration.It indicates that SA-MO is feasible and efficient for high dimensional DHM calibration.
文摘The Chinese economy has been experiencing extensive growth for decades. Along with this growth, however, there have been industrial-economic, social and environmental inefficiencies. In some regions, problems exist because of overemphasis on GDP growth, or growth at the expense of the environment. Looking at efficiency through the prism of economic, social and environmental factors, this article analyzes the industrial economic development during the 10th Five-Year Plan (2001-2005). The authors conclude that economic development should be achieved while making overall improvements to economic, social and ecoenvironment efficiency.
文摘The life-cycle eco-footprint computing model of building projects was established in the study. It contained the eco-footprint in 4 aspects during the lifecycle: consumed energy, consumed resource, emitted carbon dioxide and produced solid waste. Space efficiency of life-cycle eco-footprint index was proposed and used to assess the eco-sustainability of building projects. Then, the eco-footprint and ecosustainability of 4 different structure types(brick-concrete bungalow, multi-storey brick-concrete, multistorey steel-concrete, high-rise steel-concrete) for residential building in severely cold areas were investigated. The results indicated that: 1) Compared with bungalow, high-rise building with relatively smaller shape coefficient and window-wall ratio had higher eco-sustainability; 2) For the buildings with the same storey, shape coefficient and window-wall ratio, steel-concrete building had higher eco-sustainability than brickconcrete building; 3) High-rise steel-concrete structure had the greatest eco-sustainability during the 4 different bui lding structures, so it was more suitable to promote.
基金funded by the National Natural Science Foundation of China(Nos.31971551,31470573 and 31070478)the Tianjin Key Projects of Scientific and Technological Support(Nos.17YFZCNC00220 and 18YFZCNC01270)
文摘In the paper entitled"Efficient adsorption of Mn(Ⅱ)by layered double hydroxides intercalated with di ethylenetriaminepentaacetic acid and the mechanistic study"in Journal of Environmental Sciences,volume 85,page 56-65,there were problems with mathematical notation and dimensional errors in the calculation for Giibbs free energy.In Section 2.5:Adsorption isotherms and thermodynamics studies,authors calculated the Gibbs free energy change(△G°)
