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Dual‑Donor‑Induced Crystallinity Modulation Enables 19.23% Efficiency Organic Solar Cells
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作者 Anhai Liang Yuqing Sun +9 位作者 Sein Chung Jiyeong Shin Kangbo Sun Chaofeng Zhu Jingjing Zhao Zhenmin Zhao Yufei Zhong Guangye Zhang Kilwon Cho Zhipeng Kan 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期376-388,共13页
Trap-assisted charge recombination is one of the primary limitationsof restricting the performance of organic solar cells. However, effectivelyreducing the presence of traps in the photoactive layer remains challengin... Trap-assisted charge recombination is one of the primary limitationsof restricting the performance of organic solar cells. However, effectivelyreducing the presence of traps in the photoactive layer remains challenging.Herein, wide bandgap polymer donor PTzBI-dF is demonstrated as an effectivemodulator for enhancing the crystallinity of the bulk heterojunction active layerscomposed of D18 derivatives blended with Y6, leading to dense and orderedmolecular packings, and thus, improves photoluminescence quenching properties.As a result, the photovoltaic devices exhibit reduced trap-assisted charge recombinationlosses, achieving an optimized power conversion efficiency of over 19%.Besides the efficiency enhancement, the devices comprised of PTzBI-dF as athird component simultaneously attain decreased current leakage, improved chargecarrier mobilities, and suppressed bimolecular charge recombination, leading toreduced energy losses. The advanced crystalline structures induced by PTzBI-dFand its characteristics, such as well-aligned energy level, and complementaryabsorption spectra, are ascribed to the promising performance improvements.Our findings suggest that donor phase engineering is a feasible approach to tuning the molecular packings in the active layer, providingguidelines for designing effective morphology modulators for high-performance organic solar cells. 展开更多
关键词 Trap-assisted charge recombination PHOTOLUMINESCENCE MISCIBILITY Current leakage Power conversion efficiency
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Water-use efficiency in response to simulated increasing precipitation in a temperate desert ecosystem of Xinjiang, China 被引量:6
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作者 HUANG Gang LI Yan +2 位作者 MU Xiaohan ZHAO Hongmei CAO Yanfeng 《Journal of Arid Land》 SCIE CSCD 2017年第6期823-836,共14页
Water-use efficiency(WUE) is a key plant functional trait that plays a central role in the global cycles of water and carbon. Although increasing precipitation may cause vegetation changes, few studies have explored... Water-use efficiency(WUE) is a key plant functional trait that plays a central role in the global cycles of water and carbon. Although increasing precipitation may cause vegetation changes, few studies have explored the linkage between alteration in vegetation and WUE. Here, we analyzed the responses of leaf WUE, ecosystem carbon and water exchanges, ecosystem WUE, and plant community composition changes under normal conditions and also under extra 15% or 30% increases in annual precipitation in a temperate desert ecosystem of Xinjiang, China. We found that leaf WUE and ecosystem WUE showed inconsistent responses to increasing precipitation. Leaf WUE consistently decreased as precipitation increased. By contrast, the responses of the ecosystem WUE to increasing precipitation are different in different precipitation regimes: increasing by 33.9% in the wet year(i.e., the normal precipitation years)and decreasing by 4.1% in the dry year when the precipitation was about 30% less than that in the wet year.We systematically assessed the herbaceous community dynamics, community composition, and vegetation coverage to explain the responses of ecosystem WUE, and found that the between-year discrepancy in ecosystem WUE was consistent with the extent to which plant biomass was stimulated by the increase in precipitation. Although there was no change in the relative significance of ephemerals in the plant community, its greater overall plant biomass drove an increased ecosystem WUE under the conditions of increasing precipitation in 2011. However, the slight increase in plant biomass exerted no significant effect on ecosystem WUE in 2012. Our findings suggest that an alteration in the dominant species in this plant community can induce a shift in the carbon-and water-based economics of desert ecosystems. 展开更多
关键词 desert ecosystem ecosystem water-use efficiency gross carbon exchange increasing precipitation leaf water-use efficiency net carbon exchange Gurbantunggut Desert
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Optimizing integrative cultivation management improves grain quality while increasing yield and nitrogen use efficiency in rice 被引量:24
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作者 ZHANG Hao HOU Dan-ping +8 位作者 PENG Xian-long MA Bing-ju SHAO Shi-mei JING Wen-jiang GU Jun-fei LIU Li-jun WANG Zhi-qin LIU Yuan-ying YANG Jian-chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第12期2716-2731,共16页
A major challenge in rice(Oryza sativa L.)production is to cope with increasing grain yield and fertilizer use efficiency without compromising grain quality.This study was designed to determine if optimizing integrati... A major challenge in rice(Oryza sativa L.)production is to cope with increasing grain yield and fertilizer use efficiency without compromising grain quality.This study was designed to determine if optimizing integrative cultivation management in rice could improve grain quality while increase yield and nitrogen use efficiency(NUE).An indica-japonica hybrid rice cultivar and a japonica rice cultivar were grown in the field,with five cultivation managements including no N application(0 N),local farmer's practice(LFP),and three optimizi ng in teg rati ve cultivati on managements,reducing N rate and increasi ng plant density(ND),ND+alternate wetting and moderate soil drying irrigation(NDW),and NDW+applying rapeseed cake fertilizer(NDWR).The results showed that the optimizi ng integrative cultivati on man ageme nts could not only in crease grain yield,but also enhance NUE compared to LFP.Compared to LFP,NDWR sign ifica ntly in creased brow n,milled,head milled rice rate,ratio of the kern el le ngth to breadth and breakdown value of starch,whereas decreased amylose content,gel consiste ncy,prolamin con tent,setback value,perce ntage of chalky kern els,and chalki ness.The three optimizing in tegrative cultivation managements increased con tents of total protei ns,albumin and glutelin,activities of the key enzymes involved in the sucrose-starch con version in grains,root oxidati on activity,and malic and succinic acid concentrations in root exudates during the grain-filling period.The results suggested that optimizing integrative cultivation managements could improve grain quality meanwhile increase grain yield and NUE by enhancing physiological activities of rice plants. 展开更多
关键词 RICE INTEGRATIVE CULTIVATION MANAGEMENT YIELD grain quality nitrogen use efficiency
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Use of Controlled Release Fertilizer for Increasing N Efficiency of Direct Seeding Rice 被引量:27
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作者 FU JIANRONG, ZHU YUANHONG and JIANG LINA Institute of Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021 (China) 《Pedosphere》 SCIE CAS CSCD 2001年第4期333-339,共7页
Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilize... Field trials on a silt-loamy paddy soil derived from shallow-sea deposit in direct seeding rice fields were conducted in Zhejiang, China, in 1996 to compare N efficiency of controlled release fertilizers (LP fertilizers) with the conventional urea. Six treatments including CK (no N fertilizer), conventional urea and different types of LP fertilizers at different rates were designed for two succeeding crops of early and late rice. A blend of different types of LP fertilizers as a single preplant "co-situs" application released N in a rate and amount synchronizing with uptake pattern of direct seeding rice. A single preplant application of the LP fertilizers could meet the N requirement of rice for the whole growth period without need of topdressing. Using LP fertilizer blends, equivalent grain yields could be maintained even if the N fertilization rates were reduced by 25%~50% compared with the conventional urea. Agronomic efficiency of the LP fertilizers was 13.6%~ 86.4% higher than that of the conventional urea in early rice and 100%~164.1% in late rice, depending on the amounts of the LP fertilizers applied. N fertilizer recovery rate increased from 27.4% for the conventional application of urea to 41.7%~54.l% for the single preplant "co-situs" application of the LP fertilizers. Use of the LP fertilizers was promising if the increase in production costs due to the high LP fertilizer prices could be compensated by increase in yield and N efficiency, reduction in labor costs and improvement in environment. 展开更多
关键词 controlled release fertilizer direct seeding rice N efficiency
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Effects of increasing panicle-stage N on yield and N use efficiency of indica rice and its relationship with soil fertility 被引量:4
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作者 Chang Ye Hengyu Ma +5 位作者 Xiu Huang Chunmei Xu Song Chen Guang Chu Xiufu Zhang Danying Wang 《The Crop Journal》 SCIE CSCD 2022年第6期1784-1797,共14页
Because of the higher nitrogen(N)recovery efficiency(NRE)of panicle-stage fertilization compared with basal and tillering fertilization,increasing the proportion of N topdressing at the booting stage(panicleN)is recom... Because of the higher nitrogen(N)recovery efficiency(NRE)of panicle-stage fertilization compared with basal and tillering fertilization,increasing the proportion of N topdressing at the booting stage(panicleN)is recommended and commonly practiced in parts of China.To investigate the effects of increasing panicle-N on grain yield and N use efficiency(NUE)and the relationships of the increase and the rice cultivar and soil fertility status,we increased the percentage of panicle-N from 20%to 40%by correspondingly reducing the N amount applied only at the tillering stage in both high-and low-fertility blue clayey paddy fields in 2018 and 2019.Four indica cultivars with diverse panicle types were used,and their grain yield,dry matter accumulation,and NUE were compared.In high-fertility soil,increasing topdressing panicle-N from 20%to 40%reduced tillering ability and reduced the effective panicle numbers of the multi-and medium-panicle cultivars Huanghuazhan(HHZ),C Liangyouhuazhan(CHZ),and Tianyouhuazhan(THZ).These cultivars gave the greatest yield when 30%of N was supplied as panicle fertilizer,whereas the yield,NRE,N agronomic efficiency(NAE),and nitrogen physiological efficiency(NPE)of the heavy-panicle inbred cultivar Yangdao 6(YD6)continued to increase,resulting in improved dry matter accumulation and grain filling in the late growth stage.The yield,NAE,NRE,and NPE of YD6 peaked when the panicle-N constituted 40%.While in low-fertility soil,the multipanicle cultivar HHZ showed the greatest yield when 30%of fertilizer-N was applied once at the panicle initiation(PI)stage,while the medium-panicle cultivar CHZ showed the greatest yield when the panicle-N percentage was 40%.Our results suggest that the percentage of panicle-N fertilizer should not exceed 30%for multipanicle cultivars,while can be appropriately increased to 40%for heavy-panicle indica cultivars.The effect of increasing topdressing panicle-N on the yield of medium-panicle cultivars was related to soil fertility.The optimum panicle-N percentage was 30%in the high-fertility soil and 40%in the low-fertility soil. 展开更多
关键词 Indica rice Panicle-N YIELD Nitrogen use efficiency Soil fertility
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Practical strategies for increasing efficiency and effectiveness in critical care education 被引量:5
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作者 Maurice F Joyce Sheri Berg Edward A Bittner 《World Journal of Critical Care Medicine》 2017年第1期1-12,共12页
Technological advances and evolving demands inmedical care have led to challenges in ensuring adequate training for providers of critical care. Reliance on the traditional experience-based training model alone is insu... Technological advances and evolving demands inmedical care have led to challenges in ensuring adequate training for providers of critical care. Reliance on the traditional experience-based training model alone is insufficient for ensuring quality and safety in patient care. This article provides a brief overview of the existing educational practice within the critical care environment. Challenges to education within common daily activities of critical care practice are reviewed. Some practical evidence-based educational approaches are then described which can be incorporated into the daily practice of critical care without disrupting workflow or compromising the quality of patient care. It is hoped that such approaches for improving the efficiency and efficacy of critical care education will be integrated into training programs. 展开更多
关键词 Medical EDUCATION Critical care EDUCATIONAL efficiency EDUCATIONAL efficacy BEDSIDE teaching Flipped classroom Patient handover Multidisciplinary team practice In SITU simulation PROCEDURAL training
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Increasing Dye-Sensitized Solar Cell Efficiency by ZnO Spin-Coating of the TiO<sub>2</sub>Electrode: Effect of ZnO Amount
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作者 Fahd Al-Juaid Amar Merazga 《Energy and Power Engineering》 2013年第10期591-595,共5页
This paper is concerned with the improvement of dye-sensitized solar cell (DSSC) efficiency upon ZnO-coating of the TiO2 electrode. Sol-gel ZnO of controlled amount by varying the number of sol drops during spin-coati... This paper is concerned with the improvement of dye-sensitized solar cell (DSSC) efficiency upon ZnO-coating of the TiO2 electrode. Sol-gel ZnO of controlled amount by varying the number of sol drops during spin-coating is shown to increase the DSSC efficiency. The highest efficiency is obtained at a single sol drop with enhancement of 40%, while beyond this amount the efficiency falls down sharply to zero. Based on measured optical absorption spectra of the different dye-loaded electrodes, it is concluded that this amount of ZnO sol corresponds to the thinnest layer that can create the energy barrier to minimize the electron recombination rate without seriously affecting the dye adsorption efficiency of the TiO2 film. 展开更多
关键词 ZNO SPIN-COATING DYE-SENSITIZED Solar Cell efficiency
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Understanding Bridging Sites and Accelerating Quantum Efficiency for Photocatalytic CO_(2) Reduction 被引量:2
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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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Hydrodynamic Assessment of Increasing the Energy Efficiency of Trawler Propulsion with a Draft Tube
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作者 Jonas Eliasson Elias B. Eliasson Halldor S. Eliasson 《Open Journal of Fluid Dynamics》 2015年第2期139-144,共6页
The economy of the fishing industry is suffering from high fuel prices. Considerable efforts are invested in methods to increase the energy efficiency of fishing vessels and reducing the oil consumption per kilo of ca... The economy of the fishing industry is suffering from high fuel prices. Considerable efforts are invested in methods to increase the energy efficiency of fishing vessels and reducing the oil consumption per kilo of catch that may be as high as 0.6 to 0.7 liter oil per kilo catch. It is primarily the fact that sailing and fishing are on two very different speeds that cause these high fuel consumptions. This is called the two-speed problem and it is the trawlers that are hit hardest by it. The essence of the two-speed problem is that a hydraulic efficiency of only 28% can be expected in trawling speed, when it would be 67% if the ship is sailing at optimum speed all the time. Hydrodynamical analysis shows that an average hydraulic efficiency of only 41% can be expected for a trawler. There is no simple remedy for this, but it is possible to use a technology developed in the hydropower industry, i.e. a draft tube, or a diffuser, to recover energy that would otherwise be lost when trawling. A draft of tube the same length as the propellers diameter could mean fuel savings of 10%, a draft tube twice as long 20%. The difficulty is to find a way to get the draft tube out of the water during sailing with a vessel-specific mechanical design that is not a part of the fluid dynamics of the problem and not discussed in the paper. 展开更多
关键词 TRAWLER Energy efficiency HYDRODYNAMIC Assessment Fuel ECONOMY Draft Tube
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Enhancing I^(0)/I^(-)Conversion Efficiency by Starch Confinement in Zinc-lodine Battery 被引量:1
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作者 Danyang Zhao Qiancheng Zhu +4 位作者 Qiancheng Zhou Wenming Zhang Ying Yu Shuo Chen Zhifeng Ren 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期114-120,共7页
The redox couple of I^(0)/I^(-)in aqueous rechargeable iodine–zinc(I^(2)-Zn)batteries is a promising energy storage resource since it is safe and cost-effective,and provides steady output voltage.However,the cycle li... The redox couple of I^(0)/I^(-)in aqueous rechargeable iodine–zinc(I^(2)-Zn)batteries is a promising energy storage resource since it is safe and cost-effective,and provides steady output voltage.However,the cycle life and efficiency of these batteries remain unsatisfactory due to the uncontrolled shuttling of polyiodide(I_(3)^(-)and I_(5)^(-))and side reactions on the Zn anode.Starch is a very low-cost and widely sourced food used daily around the world.“Starch turns blue when it encounters iodine”is a classic chemical reaction,which results from the unique structure of the helix starch molecule–iodine complex.Inspired by this,we employ starch to confine the shuttling of polyiodide,and thus,the I^(0)/I^(-)conversion efficiency of an I^(2)-Zn battery is clearly enhanced.According to the detailed characterizations and theoretical DFT calculation results,the enhancement of I^(0)/I^(-)conversion efficiency is mainly originated from the strong bonding between the charged products of I_(3)^(-)and I_(5)^(-)and the rich hydroxyl groups in starch.This work provides inspiration for the rational design of high-performance and low-cost I^(2)-Zn in AZIBs. 展开更多
关键词 aqueous battery conversion efficiency iodine-zinc battery starch confinement
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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems 被引量:1
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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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Urban Land Use Efficiency and Contributing Factors in the Yangtze River Delta Under Increasing Environmental Restrictions in China
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作者 YANG Qingke WANG Lei +3 位作者 QIN Xianhong FAN Yeting WANG Yazhu DING Linlin 《Chinese Geographical Science》 SCIE CSCD 2022年第5期883-895,共13页
Evaluating urban land use efficiency(ULUE) provides insights into the interactions between land use systems and their external environment. Specifically, changes in ULUE are important for monitoring urban transformati... Evaluating urban land use efficiency(ULUE) provides insights into the interactions between land use systems and their external environment. Specifically, changes in ULUE are important for monitoring urban transformation in developing countries. In this study, using a traditional input-output index model, we incorporated slack-based measurements and undesirable outputs into a SBM-UN(slack-based measure-undesirable) model to investigate ULUE within the context of increasing environmental restrictions in China. The model was used to estimate the ULUE of 26 cities in the highly developed urban agglomeration of the Yangtze River Delta from 2000 to2018. The average ULUE in the Yangtze River Delta was relatively low compared to that of developed city regions in the European Union(EU) and North America and exhibited a U-shaped curve over the study period. Incorporating undesirable outputs, such as environmental pollution, into the model reduced ULUE by 19.06%. ULUE varied spatially, with the kernel density estimation exhibiting a bimodal distribution. Efficiency decomposition analysis showed that scale efficiency made a greater contribution to ULUE than pure technical efficiency. Based on our findings, recommended approaches to improve ULUE include optimizing factor allocation, reducing undesirable outputs, and increasing the effective output per land unit. The study suggests that ULUE and the SBM-UN model are useful planning tools for sustainable urban development. 展开更多
关键词 urban land use efficiency(ULUE) environmental restriction efficiency decomposition kernel density estimation SBM-UN(slack-based measure-undesirable)model Yangtze River Delta China
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Elucidating the enhancement of kaolinite flotation by iron content through density functional theory: A study on sodium oleate adsorption efficiency 被引量:1
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作者 Lingyun Liu Chuilei Kong +1 位作者 Hongyu Zhao Fangqin Lu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第6期855-866,共12页
This study delves into the intricate relationship between iron(Fe)content in kaolinite and its impact on the adsorption behavior of sodium oleate.The effects of different iron concentrations on adsorption energy,hydro... This study delves into the intricate relationship between iron(Fe)content in kaolinite and its impact on the adsorption behavior of sodium oleate.The effects of different iron concentrations on adsorption energy,hydrogen bond kinetics and adsorption efficiency were studied through simulation and experimental verification.The results show that the presence of iron in the kaolinite structure significantly improves the adsorption capacity of sodium oleate.Kaolinite samples with high iron content have better adsorption properties,lower adsorption energy levels and shorter and stronger hydrogen bonds than pure kaolinite.The optimal concentration of oleic acid ions for achieving maximum adsorption efficiency was identified as 1.2 mmol/L across different kaolinite samples.At this concentration,the adsorption rates and capacities reach their peak,with Fe-enriched kaolinite samples exhibiting notably higher flotation recovery rates.This optimal concentration represents a balance between sufficient oleic acid ion availability for surface interactions and the prevention of self-aggregation phenomena that could hinder adsorption.This study offers promising avenues for optimizing the flotation process in mineral processing applications. 展开更多
关键词 Iron Influence Sodium Oleate Adsorption Kaolinite Surfaces Molecular Interaction Analysis Flotation efficiency Optimization
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Microscopic characteristics of tight sandstone reservoirs and their effects on the imbibition efficiency of fracturing fluids:A case study of the Linxing area,Ordos Basin 被引量:1
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作者 Qihui Li Dazhong Ren +6 位作者 Hu Wang Haipeng Sun Tian Li Hanpeng Zhang Zhen Yan Rongjun Zhang Le Qu 《Energy Geoscience》 EI 2024年第3期328-338,共11页
The Linxing area within the Ordos Basin exhibits pronounced reservoir heterogeneity and intricate micro-pore structures,rendering it susceptible to water-blocking damage during imbibition extraction.This study delved ... The Linxing area within the Ordos Basin exhibits pronounced reservoir heterogeneity and intricate micro-pore structures,rendering it susceptible to water-blocking damage during imbibition extraction.This study delved into the traits of tight sandstone reservoirs in the 8th member of the Shihezi Formation(also referred to as the He 8 Member)in the study area,as well as their effects on fracturing fluid imbibition.Utilizing experimental techniques such as nuclear magnetic resonance(NMR),high-pressure mercury intrusion(HPMI),and gas adsorption,this study elucidated the reservoir characteristics and examined the factors affecting the imbibition through imbibition experiments.The findings reveal that:①The reservoir,with average porosity of 8.40%and average permeability of 0.642×10^(-3)μm^(2),consists principally of quartz,feldspar,and lithic fragments,with feldspathic litharenite serving as the primary rock type and illite as the chief clay mineral;②Nano-scale micro-pores and throats dominate the reservoir,with dissolution pores and intercrystalline pores serving as predominant pore types,exhibiting relatively high pore connectivity;③Imbibition efficiency is influenced by petrophysical properties,clay mineral content,and microscopic pore structure.Due to the heterogeneity of the tight sandstone reservoir,microscopic factors have a more significant impact on the imbibition efficiency of fracturing fluids;④A comparative analysis shows that average pore size correlates most strongly with imbibition efficiency,followed by petrophysical properties and clay mineral content.In contrast,the pore type has minimal impact.Micropores are vital in the imbibition process,while meso-pores and macro-pores offer primary spaces for imbibition.This study offers theoretical insights and guidance for enhancing the post-fracturing production of tight sandstone reservoirs by examining the effects of these factors on the imbibition efficiency of fracturing fluids in tight sandstones. 展开更多
关键词 Tight sandstone Ordos Basin Fracturing fluid Microscopic reservoir characteristics Imbibition efficiency Influencing factor
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Tomato Green Cultivation Technology of Reducing Fertilizer and Pesticide Input and Increasing Fertilizer Efficiency
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作者 Yongxun MAO Chun LI +2 位作者 Lanxiang MA Yuanjing XU Tao WEI 《Plant Diseases and Pests》 CAS 2022年第3期31-34,共4页
According to the technical approach of green production and yield increase pattern,green,pollution-free,quality and efficiency improvement can be achieved by reducing nitrogen,controlling phosphorus and stabilizing po... According to the technical approach of green production and yield increase pattern,green,pollution-free,quality and efficiency improvement can be achieved by reducing nitrogen,controlling phosphorus and stabilizing potassium,replenishing sulfur,zinc,iron,manganese and boron from the aspects of controlling fertilizer,drug and water.The main measures include combination use of organic and inorganic fertilizer,effective control of the amount of nitrogen and phosphate fertilizer,reduction of the application amount of chemical fertilizers and pesticides,and rational crop rotation to reduce the occurrence of diseases and insect pests,which can improve the yield and quality of tomato. 展开更多
关键词 TOMATO Intensive technology POLLUTION-FREE Quality and efficiency improvement
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Increasing the Energy Efficiency of Air Jet Weaving Based on a Novel Method to Exploit Energy Savings Potentials in Production Processes of the Textile Industry
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作者 Corrado Grassi Achim Schroter +1 位作者 Yves-Simon Gloy Thomas Gries 《Journal of Environmental Science and Engineering(B)》 2016年第1期26-34,共9页
This article deals with the energy efficiency of textile weaving machines. A method based on exergy balances has been developed at the Institute for Textile Technology RWTH Aachen University (ITA), Aachen, Germany i... This article deals with the energy efficiency of textile weaving machines. A method based on exergy balances has been developed at the Institute for Textile Technology RWTH Aachen University (ITA), Aachen, Germany in order to improve energy efficiency textile machines. The relay nozzles of the air-jet weaving technology need up to 80% of the energy of the weaving machine. At ITA, a new nozzle concept was developed. The developed geometry is a so called High-Volume-Low-Pressure nozzle (HVLP nozzle), based on convergent nozzle aerodynamic theory. With this concept, energy savings up to 30% are possible. 展开更多
关键词 Energy efficiency air jet weaving relay nozzle energy consumption.
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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network 被引量:1
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作者 Xue-Qiang Zhang Qing-Lin Cheng +2 位作者 Wei Sun Yi Zhao Zhi-Min Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期621-640,共20页
As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crud... As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems. 展开更多
关键词 Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction
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Increasing Production Efficiency through Casting Quality Improving by Electromagnetic Field Applying
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作者 Marija Mihailovic Aleksandra Pataric Zvonko GuliSija Miroslav Sokic 《Journal of Mechanics Engineering and Automation》 2012年第1期59-62,共4页
The increased production efficiency of heat treatable A1 alloys, as the result of applied electromagnetic field during continuous casting process was investigated. The applied frequency of the electromagnetic field (... The increased production efficiency of heat treatable A1 alloys, as the result of applied electromagnetic field during continuous casting process was investigated. The applied frequency of the electromagnetic field (EMF) during the AI alloys continuous casting was changing from 30 Hz to 50 Hz, while some castings were obtained without the EMF influence. The mechanical characterization of continuous casted AI alloys EN AW 2007 and En AW 2024 was done on testing machine Zwick/Roell Z 100. The microstructure of as-cast samples was examined, as well. When the frequency decreases (from 50 Hz to 30 Hz), the grain size decreases as well, what is noticeable through the finer microstructure and its uniformity throughout the cross-section. These results have shown that low frequency electromagnetic field significantly influenced the microstructure and therefore the mechanical properties of as cast ingots. Thus, through improved castings quality, operation time and energy savings, the production efficiency was increased. 展开更多
关键词 AI alloys electromagnetic field CASTING production efficiency.
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Enhanced ferroelectric and improved leakage of BFO-based thin films through increasing entropy strategy
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作者 Dongfei Lu Guoqiang Xi +5 位作者 Hangren Li Jie Tu Xiuqiao Liu Xudong Liu Jianjun Tian Linxing Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2263-2273,共11页
BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant polariza-tion.However,BFO suffers from a large leakage current,resulting in poor ferroelectric p... BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant polariza-tion.However,BFO suffers from a large leakage current,resulting in poor ferroelectric properties.Herein,the sol-gel method was used to deposit a series of BFO-based thin films on fluorine-doped tin oxide substrates,and the effects of the substitution of the elements Co,Cu,Mn(B-site)and Sm,Eu,La(A-site)on the crystal structure,ferroelectricity,and leakage current of the BFO-based thin films were invest-igated.Results confirmed that lattice distortion by X-ray diffraction can be attributed to the substitution of individual elements in the BFO-based films.Sm and Eu substitutions contribute to the lattice distortion in a pseudo-cubic structure,while La is biased toward pseudo-tet-ragonal.Piezoelectric force microscopy confirmed that reversible switching of ferroelectric domains by nearly 180°can be realized through the prepared films.The ferroelectric hysteresis loops showed that the order for the polarization contribution is as follows:Cu>Co>Mn(B-site),Sm>La>Eu(A-site).The current density voltage curves indicated that the order for leakage contribution is as follows:Mn<Cu<Co(B-site),La<Eu<Sm(A-site).Scanning electron microscopy showed that the introduction of Cu elements facilitates the formation of dense grains,and the grain size distribution statistics proved that La element promotes the reduction of grain size,leading to the increase of grain boundaries and the reduction of leakage.Finally,a Bi_(0.985)Sm_(0.045)La_(0.03)Fe_(0.96)Co_(0.02)Cu_(0.02)O_(3)(SmLa-CoCu)thin film with a qualitative leap in the remnant polarization from 25.5(Bi_(0.985)Sm_(0.075)FeO_(3))to 98.8µC/cm^(2)(SmLa-CoCu)was prepared through the syner-gistic action of Sm,La,Co,and Cu elements.The leakage current is also drastically reduced from 160 to 8.4 mA/cm^(2)at a field strength of 150 kV/cm.Thus,based on the increasing entropy strategy of chemical engineering,this study focuses on enhancing ferroelectricity and decreasing leakage current,providing a promising path for the advancement of ferroelectric devices. 展开更多
关键词 increasing entropy SYNERGISTIC ferroelectric film remnant polarization leakage current
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Does Financial Inclusion Influence Economic Efficiency of Rice Farming? Evidence from Ogun State, Nigeria
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作者 Shakirat B.IBRAHIM Raheem O.AMINU +2 位作者 Aisha O.AROWOLO Opeyemi O.OKANLAWON Afeez A.ADEGBOLA 《Rice science》 SCIE CSCD 2024年第6期638-642,I0012-I0014,共8页
Local production of rice has struggled to meet local demand despite its suitability for cultivation in many parts of Nigeria.Using data from 240 rice farmers, this study examined the economic efficiency of rice produc... Local production of rice has struggled to meet local demand despite its suitability for cultivation in many parts of Nigeria.Using data from 240 rice farmers, this study examined the economic efficiency of rice production and the effects of financial inclusion on the economic efficiency of rice farming in Ogun State, Nigeria. Data were analyzed using the Stochastic Cost Frontier model with inefficiency effects. 展开更多
关键词 NIGERIA SUITABILITY efficiency
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