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Spatiotemporal variations,influencing factors,and configurational promotion paths of energy efficiency in China’s cities
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作者 Ruyu Xu Keliang Wang +1 位作者 Zhuang Miao Lingxuan Sun 《Chinese Journal of Population,Resources and Environment》 2024年第1期74-86,共13页
The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration p... The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration promotion paths of EE in 284 Chinese cities during 2003‒2019 using the global super-efficiency minimum distance to strong efficient frontier(G-S-MinDS),exploratory spatial data analysis(ESDA),multiscale geographically weighted regression(MGWR),and fuzzy set qualitative comparative analysis(fsQCA)methods.The findings are:①China’s cities have an annual average EE of 0.658 with a growth rate of 0.53%,showing considerable promotion potential.②Industrial structure optimization,population agglomeration,economic development,and increased green coverage contribute positively,while government intervention and openness hinder China’s urban EE.③Four configurational promotion paths for enhancing China’s urban EE are identified,where among those paths population density is a core condition,while government intervention is not.This study provides valuable insights into substantially improving urban EE,emphasizing the need for targeted policies to address energy and environmental crises in China. 展开更多
关键词 Energy efficiency Spatiotemporal variations Influencing factors Configurational promotion paths
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Evaluation of Energy Efficiency and Analysis of Influencing Factors of Company CW’s Manufacturing Workshops
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作者 Pengju Zhang 《Journal of Electronic Research and Application》 2024年第2期18-26,共9页
In this work,the Slacks-Based Measure(SBM)model within Data Envelopment Analysis was employed to establish a set of indicators for evaluating the energy efficiency of manufacturing workshops.The energy efficiency of 1... In this work,the Slacks-Based Measure(SBM)model within Data Envelopment Analysis was employed to establish a set of indicators for evaluating the energy efficiency of manufacturing workshops.The energy efficiency of 12 Company CW’s manufacturing workshops from 2016 to 2022 was assessed.The findings indicated that aside from a few workshops operating at the production frontier,the rest exhibit significant fluctuations in energy efficiency and generally low energy efficiency.Subsequently,a combined GRA-Tobit analysis model was introduced to identify factors influencing the energy efficiency of Company CW’s manufacturing workshops.Regression analysis revealed that technological investments,employee quality,workshop production scale,investment in clean energy,and the level of pollution control all significantly impact the energy efficiency of Company CW’s manufacturing workshops.By evaluating the energy efficiency of Company CW’s manufacturing workshops and studying their influencing factors,this research aids company managers in understanding the energy efficiency of the manufacturing process.It optimizes the combination of various production elements,thereby offering effective guidance for improving the energy efficiency issues of the company’s manufacturing workshops,which can contribute to enhancing the corporation’s overall energy efficiency. 展开更多
关键词 Manufacturing workshop energy efficiency Energy efficiency evaluation Data Envelopment Analysis(DEA) GRA-Tobit model
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Probing the influence of secondary fracture connectivity on fracturing fluid flowback efficiency 被引量:2
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作者 Yi-Ning Wu Li-Sha Tang +5 位作者 Yuan Li Li-Yuan Zhang Xu Jin Ming-Wei Zhao Xiang Feng Cai-Li Dai 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期973-981,共9页
A deep understanding of the geometric impacts of fracture on fracturing fluid flowback efficiency is essential for unconventional oil development. Using nuclear magnetic resonance and 2.5-dimensional matrix-fracture v... A deep understanding of the geometric impacts of fracture on fracturing fluid flowback efficiency is essential for unconventional oil development. Using nuclear magnetic resonance and 2.5-dimensional matrix-fracture visualization microfluidic models, qualitative and quantitative descriptions of the influences of connectivity between primary fracture and secondary fracture on flowback were given from core scale to pore network scale. The flow patterns of oil-gel breaking fluid two-phase flow during flowback under different fracture connectivity were analyzed. We found some counterintuitive results that non-connected secondary fracture (NCSF, not connect with artificial primary fracture and embedded in the matrix) is detrimental to flowbackefficiency. The NCSF accelerates the formation of oil channeling during flowback, resulting in a large amount of fracturing fluid trapped in the matrix, which is not beneficial for flowback. Whereas the connected secondary fracture (CSF, connected with the artificial primary fracture) is conducive to flowback. The walls of CSF become part of primary fracture, which expands the drainage area with low resistance, and delays the formation of the oil flow channel. Thus, CSF increases the high-speed flowback stage duration, thereby enhancing the flowback efficiency. The fracturing fluid flowback efficiency investigated here follows the sequence of the connected secondary fracture model (72%) > the matrix model (66%) > the non-connected secondary fracture model (38%). Our results contribute to hydraulic fracturing design and the prediction of flowback efficiency. 展开更多
关键词 Fracturing fluid Secondary fracture connectivity Flowback efficiency Dual media Microfluidic model
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Measurement of Digital Economy Development Level in Yangtze River Delta and Its Influence on Ecological Efficiency 被引量:1
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作者 Qing QIAO 《Asian Agricultural Research》 2023年第11期24-26,共3页
Based on the panel data of 41 cities in the Yangtze River Delta from 2007 to 2018,this paper empirically tests the impact of digital economy development on urban ecological efficiency in the Yangtze River Delta.The re... Based on the panel data of 41 cities in the Yangtze River Delta from 2007 to 2018,this paper empirically tests the impact of digital economy development on urban ecological efficiency in the Yangtze River Delta.The results show that the development level of digital economy in Yangtze River Delta urban agglomeration is fluctuating and rising;the development of digital economy has a significant positive role in promoting the improvement of urban ecological efficiency;there is significant regional heterogeneity in the promotion of ecological efficiency by digital economy,especially in central cities. 展开更多
关键词 Yangtze River Delta urban agglomeration Digital economy Ecological efficiency
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Influence of Sorbent Type on Drying Efficiency, Production Costs and Nutritional Values of Mango By-Products Feeds for Livestock
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作者 Kiendrébéogo Timbilfou Koadia Marcelle Grâce +3 位作者 Sodre Etienne Barry Drissa Ouedraogo Zangbéwindin Isidor Tarpaga Vianey 《Food and Nutrition Sciences》 2023年第12期1221-1231,共11页
The aim of the study was to determine the best food absorbents between wheat, rice and maize bran and palm kernel cake, from a technical and economic point of view, in order to make a better recommandation for their u... The aim of the study was to determine the best food absorbents between wheat, rice and maize bran and palm kernel cake, from a technical and economic point of view, in order to make a better recommandation for their use in the production process of food based on mango by-products (peels, peels + pulp). To this end, series of 18 kg of fresh feed were prepared and spread out in a stall for sun-drying using a randomized Fisher system. Preparations were made using either mango peels (75%) + absorbent (25%) or pulp + mango peels (67%) + sorbent (33%). The results show that mango Peel feed loses more water (WL) with lover production yields (PY), higher mango incorporation rates into dry feed (MRI), longer drying times (UDT) and lower production costs (CPkgPD) than mango peel + pulp. The average DM, MAT, ADF and NDF fiber contents were almost equal to those of mango peels + pulp feed. The average Crude Fiber (CF) (25.13%) and DEp (2839 kcal/kgDM) contents were higher for mango skin feed than for mango skin + pulp feed, at 8.59% and 2536 for MAT and DEp respectively. Mango peels + wheat bran (PSB25) and whole mango (MESB33) feeds recorded the highest and almost equal levels of TCP, NDF and MM. Production costs per kg of feed dry mater (CPkgDM) for feed produced at 25% were on average 33% higher than for whole mango (WM) feed. Excluding mango raw material, palm kernel meal (PK), rice bran (RB), maize bran (MB) and wheat bran (WB) can be ranked 1st, 2nd, 3rd and 4th in terms of cumulative performance of production parameters. Producers can then choose the type of sorbent they wish to use according to this ranking and the local availability of the sorbent. These feeds can be used for both ruminants and monogastrics, but are better suited to ruminant feeding due to their high fiber content. 展开更多
关键词 Mango Provends Food Absorbent Drying efficiency Nutritional Values An-imal Feed Ivory Coast
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Study on Carbon Emission Efficiency Evaluation and Influencing Factors of Chinese Pharmaceutical Manufacturing Industry
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作者 Ying Cui Shuzhen Chu 《Pharmacology & Pharmacy》 2023年第4期98-111,共14页
To measure the carbon emission efficiency of China’s pharmaceutical manufacturing industry, explore the factors affecting the carbon emission efficiency of China’s pharmaceutical manufacturing industry, and provide ... To measure the carbon emission efficiency of China’s pharmaceutical manufacturing industry, explore the factors affecting the carbon emission efficiency of China’s pharmaceutical manufacturing industry, and provide reference for improving the carbon emission efficiency of China’s pharmaceutical manufacturing industry and promoting the government to formulate macro policies. Based on the data of the pharmaceutical manufacturing industry in 30 provinces of China from 2010 to 2019, and based on the SBM model and ML (Malmquist-Luenberger) index model, the carbon emission efficiency of the pharmaceutical manufacturing industry was calculated and its dynamic change was investigated, and the Tobit model was further used to explore the influencing factors of the carbon emission efficiency of the pharmaceutical manufacturing industry. The carbon emission efficiency of China’s inter-provincial pharmaceutical manufacturing industry has steadily improved. The carbon emission efficiency of the eastern region is higher than that of the western region, and that of the western region is higher than that of the central region. The eastern region is dominated by technological progress, and there is room for improvement in technological efficiency. The central and western regions are dominated by technological efficiency. Compared with technological efficiency, technological progress needs to be further improved. Environmental regulation, industrial agglomeration and technological innovation level positively affect carbon emission efficiency, while foreign investment level has no significant impact on carbon emission efficiency. 展开更多
关键词 Carbon Emission efficiency SBM Model ML Index Pharmaceutical Manufacturing Tobit Model
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Evaluation and Influencing Factors of Urban Renewal Efficiency Based on SBM Model:A Case Study of the First Batch of Pilot Cities for Urban Renewal
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作者 LIU Shen’ao ZHOU Xia 《Journal of Landscape Research》 2023年第5期28-34,40,共8页
China is already in the second half of the urbanization process,which means that the urbanization path in China needs to shift from“large-scale expansion development”in the past to“comprehensive and refined operat... China is already in the second half of the urbanization process,which means that the urbanization path in China needs to shift from“large-scale expansion development”in the past to“comprehensive and refined operation”.To explore how to efficiently carry out urban renewal work,from the perspective of urban renewal efficiency,the first batch of pilot cities for urban renewal released by the Ministry of Housing and Urban Development in 2021 are selected as the objects.And the SBM model and Malmquist index are used to calculate and analyze their urban renewal efficiency.The results indicate that among the 20 pilot cities,Beijing,Tangshan,Suzhou,Tongling,and Jingdezhen are of high grade,and Hohhot,Xiamen,Huangshi,and Yinchuan are of medium grade,while the rest of the cities are of low grade.The regression results of the Tobit model indicate that population density,real estate investment,and regional economic development level are the main influencing factors of urban renewal.Finally,constructive suggestions are proposed for urban renewal from four aspects:concept,technology,real estate,and policy. 展开更多
关键词 Urban renewal SBM model Urban renewal efficiency
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Enhancing Energy Efficiency with a Dynamic Trust Measurement Scheme in Power Distribution Network
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作者 Yilei Wang Xin Sun +4 位作者 Guiping Zheng Ahmar Rashid Sami Ullah Hisham Alasmary Muhammad Waqas 《Computers, Materials & Continua》 SCIE EI 2024年第3期3909-3927,共19页
The application of Intelligent Internet of Things(IIoT)in constructing distribution station areas strongly supports platform transformation,upgrade,and intelligent integration.The sensing layer of IIoT comprises the e... The application of Intelligent Internet of Things(IIoT)in constructing distribution station areas strongly supports platform transformation,upgrade,and intelligent integration.The sensing layer of IIoT comprises the edge convergence layer and the end sensing layer,with the former using intelligent fusion terminals for real-time data collection and processing.However,the influx of multiple low-voltage in the smart grid raises higher demands for the performance,energy efficiency,and response speed of the substation fusion terminals.Simultaneously,it brings significant security risks to the entire distribution substation,posing a major challenge to the smart grid.In response to these challenges,a proposed dynamic and energy-efficient trust measurement scheme for smart grids aims to address these issues.The scheme begins by establishing a hierarchical trust measurement model,elucidating the trust relationships among smart IoT terminals.It then incorporates multidimensional measurement factors,encompassing static environmental factors,dynamic behaviors,and energy states.This comprehensive approach reduces the impact of subjective factors on trust measurements.Additionally,the scheme incorporates a detection process designed for identifying malicious low-voltage end sensing units,ensuring the prompt identification and elimination of any malicious terminals.This,in turn,enhances the security and reliability of the smart grid environment.The effectiveness of the proposed scheme in pinpointing malicious nodes has been demonstrated through simulation experiments.Notably,the scheme outperforms established trust metric models in terms of energy efficiency,showcasing its significant contribution to the field. 展开更多
关键词 IIoT trusted measure energy efficient
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OsNPF3.1,a nitrate,abscisic acid and gibberellin transporter gene,is essential for rice tillering and nitrogen utilization efficiency
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作者 Junnan Hang Bowen Wu +3 位作者 Diyang Qiu Guo Yang Zhongming Fang Mingyong Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1087-1104,共18页
Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone ... Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone transport and rice growth and development remains unknown.In this study,we described OsNPF3.1 as an essential nitrate and phytohormone transporter gene for rice tillering and nitrogen utilization efficiency(NUtE).OsNPF3.1 possesses four major haplotypes of its promoter sequence in 517 cultivars,and its expression is positively associated with tiller number.Its expression was higher in the basal part,culm,and leaf blade than in other parts of the plant,and was strongly induced by nitrate,abscisic acid(ABA)and gibberellin 3(GA_3)in the root and shoot of rice.Electrophysiological experiments demonstrated that OsNPF3.1 is a pH-dependent low-affinity nitrate transporter,with rice protoplast uptake assays showing it to be an ABA and GA_3 transporter.OsNPF3.1 overexpression significantly promoted ABA accumulation in the roots and GA accumulation in the basal part of the plant which inhibited axillary bud outgrowth and rice tillering,especially at high nitrate concentrations.The NUtE of OsNPF3.1-overexpressing plants was enhanced under low and medium nitrate concentrations,whereas the NUtE of OsNPF3.1 clustered regularly interspaced short palindromic repeats(CRISPR)plants was increased under high nitrate concentrations.The results indicate that OsNPF3.1 transports nitrate and phytohormones in different rice tissues under different nitrate concentrations.The altered OsNPF3.1 expression improves NUtE in the OsNPF3.1-overexpressing and CRISPR lines at low and high nitrate concentrations,respectively. 展开更多
关键词 rice tillering grain yield PHYTOHORMONE NITRATE transporter nitrogen utilization efficiency
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Mg-doped,carbon-coated,and prelithiated SiO_(x) as anode materials with improved initial Coulombic efficiency for lithium-ion batteries
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作者 Bin Liu Jie Liu +1 位作者 Cheng Zhong Wenbin Hu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期204-214,共11页
Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium si... Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium silicates during the first cycle.In this work,we modify SiO_(x) by solid-phase Mg doping reaction using low-cost Mg powder as a reducing agent.We show that Mg reduces SiO_(2) in SiO_(x) to Si and forms MgSiO_(3) or Mg_(2)SiO_(4).The MgSiO_(3) or Mg_(2)SiO_(4) are mainly distributed on the surface of SiO_(x),which suppresses the irreversible lithium-ion loss and enhances the ICE of SiO_(x).However,the formation of MgSiO_(3) or Mg_(2)SiO_(4) also sacrifices the capacity of SiO_(x).Therefore,by controlling the reaction process between Mg and SiO_(x),we can tune the phase composition,proportion,and morphology of the Mg-doped SiO_(x) and manipulate the performance.We obtain samples with a capacity of 1226 mAh g^(–1) and an ICE of 84.12%,which show significant improvement over carbon-coated SiO_(x) without Mg doping.By the synergistical modification of both Mg doping and prelithiation,the capacity of SiO_(x) is further increased to 1477 mAh g^(–1) with a minimal compromise in the ICE(83.77%). 展开更多
关键词 initial Coulombic efficiency lithium-ion batteries magnesium doping prelithiation silicon suboxide
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High Energy Efficiency Dynamic Connected Hybrid Precoding for mm Wave Massive MIMO Systems
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作者 Du Ruiyan Liu Huajing +1 位作者 Li Tiangui Liu Fulai 《China Communications》 SCIE CSCD 2024年第5期36-44,共9页
This paper considers a high energy efficiency dynamic connected(HEDC)structure,which promotes the practicability and reduces the power consumption of hybrid precoding system by lowresolution phase shifters(PSs).Based ... This paper considers a high energy efficiency dynamic connected(HEDC)structure,which promotes the practicability and reduces the power consumption of hybrid precoding system by lowresolution phase shifters(PSs).Based on the proposed structure,a new hybrid precoding algorithm is presented to optimize the energy efficiency,namely,HP-HEDC algorithm.Firstly,via a new defined effective optimal precoding matrix,the problem of optimizing the analog switch precoding matrix is formulated as a sparse representation problem.Thus,the optimal analog switch precoding matrix can be readily obtained by the branch-and-bound method.Then,the digital precoding matrix optimization problem is modeled as a dictionary update problem and solved by the method of optimal direction(MOD).Finally,the diagonal entries of the analog PS precoding matrix are optimized by exhaustive search independently since PS and antenna is one-to-one.Simulation results show that the HEDC structure enjoys low power consumption and satisfactory spectral efficiency.The proposed algorithm presents at least 50%energy efficiency improvement compared with other algorithms when the PS resolution is set as 3-bit. 展开更多
关键词 energy efficiency hybrid precoding mmWave optimized resolution phase shifter
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Cooperative activation of sodium channels for downgrading the energy efficiency in neuronal information processing
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作者 严浩然 颜家琦 +1 位作者 俞连春 邵玉峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期758-763,共6页
The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological systems.This raises the problem why neurons would favor independent over cooperative channel a... The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological systems.This raises the problem why neurons would favor independent over cooperative channel activation.In this study,we evaluate how cooperative activation of sodium channels affects the neuron’s information processing and energy consumption.Simulations of the stochastic Hodgkin–Huxley model with cooperative activation of sodium channels show that,while cooperative activation enhances neuronal information processing capacity,it greatly increases the neuron’s energy consumption.As a result,cooperative activation of sodium channel degrades the energy efficiency for neuronal information processing.This discovery improves our understanding of the design principles for neural systems,and may provide insights into future designs of the neuromorphic computing devices as well as systematic understanding of pathological mechanisms for neural diseases. 展开更多
关键词 energy efficiency ion channel noise action potential generation neuronal dynamics
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High-Efficiency Dynamic Scanning Strategy for Powder Bed Fusion by Controlling Temperature Field of the Heat-Affected Zone
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作者 Xiaokang Huang Xiaoyong Tian +5 位作者 Qi Zhong Shunwen He Cunbao Huo Yi Cao Zhiqiang Tong Dichen Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期203-214,共12页
Improvement of fabrication efficiency and part performance was the main challenge for the large-scale powder bed fusion(PBF)process.In this study,a dynamic monitoring and feedback system of powder bed temperature fiel... Improvement of fabrication efficiency and part performance was the main challenge for the large-scale powder bed fusion(PBF)process.In this study,a dynamic monitoring and feedback system of powder bed temperature field using an infrared thermal imager has been established and integrated into a four-laser PBF equipment with a working area of 2000 mm×2000 mm.The heat-affected zone(HAZ)temperature field has been controlled by adjusting the scanning speed dynamically.Simultaneously,the relationship among spot size,HAZ temperature,and part performance has been established.The fluctuation of the HAZ temperature in four-laser scanning areas was decreased from 30.85℃to 17.41℃.Thus,the consistency of the sintering performance of the produced large component has been improved.Based on the controllable temperature field,a dynamically adjusting strategy for laser spot size was proposed,by which the fabrication efficiency was improved up to 65.38%.The current research results were of great significance to the further industrial applications of large-scale PBF equipment. 展开更多
关键词 Powder bed fusion efficiency LARGE-SCALE Spot size Heat-affected zone(HAZ)
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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems
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作者 Francis Levi A.DURANO Jon Marx SARMIENTO +1 位作者 Larry N.DIGAL Pedro A.ALVIOLA IV 《Journal of Mountain Science》 SCIE CSCD 2024年第1期33-48,共16页
Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa ... Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas. 展开更多
关键词 Cocoa farms Cobb-Douglas production function ELEVATION Philippines Stochastic frontier analysis Technical efficiency
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A hierarchical salt-rejection strategy for sustainable and high-efficiency solar-driven desalination
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作者 Zhengyi Mao Xuliang Chen +7 位作者 Yingxian Chen Junda Shen Jianpan Huang Yuhan Chen Xiaoguang Duan Yicheng Han Kannie Wai Yan Chan Jian LU 《Nano Materials Science》 EI CAS CSCD 2024年第1期38-43,共6页
Solar steam generation(SSG)is widely regarded as one of the most sustainable technologies for seawater desalination.However,salt fouling severely compromises the evaporation performance and lifetime of evaporators,lim... Solar steam generation(SSG)is widely regarded as one of the most sustainable technologies for seawater desalination.However,salt fouling severely compromises the evaporation performance and lifetime of evaporators,limiting their practical applications.Herein,we propose a hierarchical salt-rejection(HSR)strategy to prevent salt precipitation during long-term evaporation while maintaining a rapid evaporation rate,even in high-salinity brine.The salt diffusion process is segmented into three steps—insulation,branching diffusion,and arterial transport—that significantly enhance the salt-resistance properties of the evaporator.Moreover,the HSR strategy overcomes the tradeoff between salt resistance and evaporation rate.Consequently,a high evaporation rate of 2.84 kg m^(-2) h^(-1),stable evaporation for 7 days cyclic tests in 20 wt%NaCl solution,and continuous operation for 170 h in natural seawater under 1 sun illumination were achieved.Compared with control evaporators,the HSR evaporator exhibited a>54%enhancement in total water evaporation mass during 24 h continuous evaporation in 20 wt%salt water.Furthermore,a water collection device equipped with the HSR evaporator realized a high water purification rate(1.1 kg m^(-2) h^(-1)),highlighting its potential for agricultural applications. 展开更多
关键词 Solar water evaporation 3D printing Salt-rejection Hierarchical structures High efficiency
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Reheat effect on the improvement in efficiency of the turbine driven by pulse detonation
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作者 Junyu Liu Zhiwu Wang +3 位作者 Zixu Zhang Junlin Li Weifeng Qin Jingjing Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期200-210,共11页
Due to the strong unsteadiness of pulse detonation,large flow losses are generated when the detonation wave interacts with the turbine blades,resulting in low turbine efficiency.Considering that the flow losses are di... Due to the strong unsteadiness of pulse detonation,large flow losses are generated when the detonation wave interacts with the turbine blades,resulting in low turbine efficiency.Considering that the flow losses are dissipated into the gas as heat energy,some of them can be recycled during the expansion process in subsequent stages by the reheat effect,which should be helpful to improve the detonationdriven turbine efficiency.Taking this into account,this paper developed a numerical model of the detonation chamber coupled with a two-stage axial turbine,and a stoichiometric hydrogen-air mixture was used.The improvement in turbine efficiency attributable to the reheat effect was calculated by comparing the average efficiency of the stages with the efficiency of the two-stage turbine.The research indicated that the first stage was critical in suppressing the flow unsteadiness caused by pulse detonation,which stabilized the intake condition of the second stage and consequently allowed much of the flow losses from the first stage to be recycled,so that the efficiency of the two-stage turbine was improved.At a 95%confidence level,the efficiency improvement was stable at 4.5%—5.3%,demonstrating that the reheat effect is significant in improving the efficiency of the detonation-driven turbine. 展开更多
关键词 Pulse detonation turbine engine Hydrogen detonation Turbine efficiency Reheat effect Multi-cycle detonation
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Enhancing the crystallinity and stability of perovskite solar cells with 4-tert-butylpyridine induction for efficiency exceeding 24%
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作者 You Liu Lishuang Zheng +15 位作者 Kuanxiang Zhang Kun Xu Weicheng Xie Jue Zhang Yulu Tian Tianyuan Liu Hanzhong Xu Ruoming Maa Wei Huang Jiahui Chen Jusheng Bao Chen Chen Yongsheng Zhou Xuchun Wang Junming Chen Jungan Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期1-7,I0001,共8页
Perovskite solar cells(PSCs)have emerged as a promising photovoltaic technology because of their high light absorption coefficient,long carrier diffusion distance,and tunable bandgap.However,PSCs face challenges such ... Perovskite solar cells(PSCs)have emerged as a promising photovoltaic technology because of their high light absorption coefficient,long carrier diffusion distance,and tunable bandgap.However,PSCs face challenges such as hysteresis effects and stability issues.In this study,we introduced a novel approach to improve film crystallization by leveraging 4-tert-butylpyridine(TBP)molecules,thereby enhancing the performance and stability of PSCs.Our findings demonstrate the effective removal of PbI_(2)from the perovskite surface through strong coordination with TBP molecules.Additionally,by carefully adjusting the concentration of the TBP solution,we achieved enhanced film crystallinity without disrupting the perovskite structure.The TBP-treated perovskite films exhibit a low defect density,improved crystallinity,and improved carrier lifetime.As a result,the PSCs manufactured with TBP treatment achieve power conversion efficiency(PCE)exceeding 24%.Moreover,we obtained the PCE of 21.39%for the 12.25 cm^(2)module. 展开更多
关键词 4-tert-butylpyridine Film crystallization Perovskite solar cells Power conversion efficiency Stability improvement
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Understanding Bridging Sites and Accelerating Quantum Efficiency for Photocatalytic CO_(2) Reduction
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作者 Kangwang Wang Zhuofeng Hu +8 位作者 Peifeng Yu Alina M.Balu Kuan Li Longfu Li Lingyong Zeng Chao Zhang Rafael Luque Kai Yan Huixia Luo 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期68-84,共17页
We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO_(2) reduction reaction(CO_(2)RR)via Mo–S bridging bonds sites in... We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO_(2) reduction reaction(CO_(2)RR)via Mo–S bridging bonds sites in S_(v)–In_(2)S_(3)@2H–MoTe_(2).The X-ray absorption near-edge structure shows that the formation of S_(v)–In_(2)S_(3)@2H–MoTe_(2) adjusts the coordination environment via interface engineering and forms Mo–S polarized sites at the interface.The interfacial dynamics and catalytic behavior are clearly revealed by ultrafast femtosecond transient absorption,time-resolved,and in situ diffuse reflectance–Infrared Fourier transform spectroscopy.A tunable electronic structure through steric interaction of Mo–S bridging bonds induces a 1.7-fold enhancement in S_(v)–In_(2)S_(3)@2H–MoTe_(2)(5)photogenerated carrier concentration relative to pristine S_(v)–In_(2)S_(3).Benefiting from lower carrier transport activation energy,an internal quantum efficiency of 94.01%at 380 nm was used for photocatalytic CO_(2)RR.This study proposes a new strategy to design photocatalyst through bridging sites to adjust the selectivity of photocatalytic CO_(2)RR. 展开更多
关键词 Quantum efficiency Electronic structure Steric interaction Bridging sites CO_(2)reduction
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Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses
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作者 Ting Wang Qing Xu +4 位作者 Beibei Zhang Deqiang Gao Ying Zhang Jing Jiang Haijun Zuo 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期42-53,共12页
Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and... Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates. 展开更多
关键词 Stable carbon isotope Water use efficiency THINNING Understory removal Photosynthetic capacity Needle water potential
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Regulation effects of water and nitrogen on yield,water,and nitrogen use efficiency of wolfberry
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作者 GAO Yalin QI Guangping +7 位作者 MA Yanlin YIN Minhua WANG Jinghai WANG Chen TIAN Rongrong XIAO Feng LU Qiang WANG Jianjun 《Journal of Arid Land》 SCIE CSCD 2024年第1期29-45,共17页
Wolfberry(Lycium barbarum L.)is important for health care and ecological protection.However,it faces problems of low productivity and resource utilization during planting.Exploring reasonable models for water and nitr... Wolfberry(Lycium barbarum L.)is important for health care and ecological protection.However,it faces problems of low productivity and resource utilization during planting.Exploring reasonable models for water and nitrogen management is important for solving these problems.Based on field trials in 2021 and 2022,this study analyzed the effects of controlling soil water and nitrogen application levels on wolfberry height,stem diameter,crown width,yield,and water(WUE)and nitrogen use efficiency(NUE).The upper and lower limits of soil water were controlled by the percentage of soil water content to field water capacity(θ_(f)),and four water levels,i.e.,adequate irrigation(W0,75%-85%θ_(f)),mild water deficit(W1,65%-75%θ_(f)),moderate water deficit(W2,55%-65%θ_(f)),and severe water deficit(W3,45%-55%θ_(f))were used,and three nitrogen application levels,i.e.,no nitrogen(N0,0 kg/hm^(2)),low nitrogen(N1,150 kg/hm^(2)),medium nitrogen(N2,300 kg/hm^(2)),and high nitrogen(N3,450 kg/hm^(2))were implied.The results showed that irrigation and nitrogen application significantly affected plant height,stem diameter,and crown width of wolfberry at different growth stages(P<0.01),and their maximum values were observed in W1N2,W0N2,and W1N3 treatments.Dry weight per plant and yield of wolfberry first increased and then decreased with increasing nitrogen application under the same water treatment.Dry weight per hundred grains and dry weight percentage increased with increasing nitrogen application under W0 treatment.However,under other water treatments,the values first increased and then decreased with increasing nitrogen application.Yield and its component of wolfberry first increased and then decreased as water deficit increased under the same nitrogen treatment.Irrigation water use efficiency(IWUE,8.46 kg/(hm^(2)·mm)),WUE(6.83 kg/(hm^(2)·mm)),partial factor productivity of nitrogen(PFPN,2.56 kg/kg),and NUE(14.29 kg/kg)reached their highest values in W2N2,W1N2,W1N2,and W1N1 treatments.Results of principal component analysis(PCA)showed that yield,WUE,and NUE were better in W1N2 treatment,making it a suitable water and nitrogen management mode for the irrigation area of the Yellow River in the Gansu Province,China and similar planting areas. 展开更多
关键词 water deficit growth characteristics YIELD water and nitrogen use efficiency principal component analysis
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