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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:3
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake value-added chemicals Bioactive components Biobased materials
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Upcycling plastic wastes into value-added products via electrocatalysis and photoelectrocatalysis 被引量:1
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作者 Sungsoon Kim Dongjae Kong +1 位作者 Xiaolin Zheng Jong Hyeok Park 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期522-541,共20页
Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern society.Nevertheless,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only ... Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern society.Nevertheless,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only 9%,has led to a monumental environmental crisis.Plastic recycling has emerged as a vital response to this crisis,offering sustainable solutions to mitigate its environmental impact.Among these recycling efforts,plastic upcycling has garnered attention,which elevates discarded plastics into higher-value products.Here,electrocatalytic and photoelectrocatalytic treatments stand at the forefront of advanced plastic upcycling.Electrocatalytic or photoelectrocatalytic treatments involve chemical reactions that facilitate electron transfer through the electrode/electrolyte interface,driven by electrical or solar energy,respectively.These methods enable precise control of chemical reactions,harnessing potential,current density,or light to yield valuable chemical products.This review explores recent progress in plastic upcycling through electrocatalytic and photoelectrocatalytic pathways,offering promising solutions to the plastic waste crisis and advancing sustainability in the plastics industry. 展开更多
关键词 Plastic upcycling Electrocatalytic reaction Photoelectrocatalytic reaction value-added product
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Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system
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作者 Zongyou Cheng Qing Zhao +3 位作者 Mengjie Tao Jijun Du Xingxi Huang Chengjun Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期92-101,共10页
In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entro... In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower costs.In this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen reduction.The phases and magnetic properties of FeCoNi medium entropy alloy were investigated.Results showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal reduction.The alloy prepared by hydrogen reduction was uniform and showed a relatively high purity.Moreover,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity. 展开更多
关键词 medium entropy alloy SOL-GEL CO-PRECIPITATION carbothermal hydrogen reduction
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基于ENTROPY-TOPSIS算法的电路实验课程综合成绩评定方法
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作者 徐航 孙曼 +2 位作者 印月 王东平 吴海祥 《实验科学与技术》 2024年第2期108-112,共5页
针对高校实践教学成绩评定环节中存在的不足,该文将基于修正ENTROPY-TOPSIS算法应用到实验课程成绩评定当中,并推导了具体算法原理。同时将该算法与常用权值算法层次分析法以及CRITIC算法在电路实践成绩客观赋权过程中进行了横向对比。... 针对高校实践教学成绩评定环节中存在的不足,该文将基于修正ENTROPY-TOPSIS算法应用到实验课程成绩评定当中,并推导了具体算法原理。同时将该算法与常用权值算法层次分析法以及CRITIC算法在电路实践成绩客观赋权过程中进行了横向对比。结果显示该方法可以为多源异构数据的科学赋权提供理论依据,有效消除因主观因素带来的不合理性,使教师在实验成绩的评定上更加趋向于客观化、科学化。 展开更多
关键词 成绩评价 CRITIC算法 entropy算法 TOPSIS算法 赋权
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Artificial photosynthesis for high-value-added chemicals:Old material,new opportunity 被引量:7
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作者 Sungsoon Kim Kwang Hee Kim +2 位作者 Cheoulwoo Oh Kan Zhang Jong Hyeok Park 《Carbon Energy》 SCIE CAS 2022年第1期21-44,共24页
Solar energy utilization has drawn attention due to ever-increasing environmental and energy issues.Photoelectrochemical(PEC)and photocatalytic(PC)water splitting for hydrogen production,which is the most popular and ... Solar energy utilization has drawn attention due to ever-increasing environmental and energy issues.Photoelectrochemical(PEC)and photocatalytic(PC)water splitting for hydrogen production,which is the most popular and well-established solar-to-chemical conversion process,has been studied thoroughly to date but is now facing limitations related to low conversion efficiency.To resolve this issue,research in PEC cells or photocatalysts has recently aimed to produce alternative value-added chemicals by modifying their redox reactions,which potentially enables high economic reward to compensate for the low efficiency.Here,various kinds of redox reactions that decouple classic water splitting reactions to produce value-added chemicals via PEC and PC processes are introduced.Successful coupling of CO_(2) reduction,O_(2) reduction and organic synthesis with either water oxidation or water reduction is comprehensively discussed from the perspective of basic fundamental and product selectivity in terms of the band structure of materials,cocatalyst design,and thermodynamics and kinetics of the reactions.Throughout the review,future challenges and opportunities are suggested with respect to the redesigned artificial synthesis,which might be an alternative development for the commercialization of PEC or PC value-added chemical production technologies in the near future. 展开更多
关键词 artificial photosynthesis PHOTOCATALYSTS photoelectrochemical cells redox reactions value-added chemical production
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Food processing wastewater purification by microalgae cultivation associated with high value-added compounds production——A review 被引量:3
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作者 Shuhong Li Shuang Zhao +4 位作者 Siliang Yan Yiting Qiu Chunfeng Song Yang Li Yutaka Kitamura 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第12期2845-2856,共12页
Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production.However,the high energy cost associated with complicated b... Microalgae have been considered as an efficient microorganism for wastewater treatment with simultaneously bioenergy and high value-added compounds production.However,the high energy cost associated with complicated biorefinery(e.g.microalgae cultivation,harvesting,drying,extraction,conversion,and purification)is a critical challenge that inhibits its large-scale application.Among different nutrition(e.g.carbon,nitrogen and phosphorous)sources,food processing wastewater is a relative safe and suitable one for microalgae cultivation due to its high organic content and low toxicity.In this review,the characteristic of different food wastewater is summarized and compared.The potential routes of value-added products(i.e.biofuel,pigment,polysaccharide,and amino acid)production along with wastewater purification are introduced.The existing challenges(e.g.biorefinery cost,efficiency and mechanism)of microalgal-based wastewater treatment are also discussed.The prospective of microalgae-based food processing wastewater treatment strategies(such as microalgae-bacteria consortium,poly-generation of bioenergy and value-added products)is forecasted.It can be observed that food wastewater treatment by microalgae could be a promising strategy to commercially realize waste source reduce,conversion and reutilization. 展开更多
关键词 Food wastewater MICROALGAE value-added PRODUCE BIOFUEL POLYSACCHARIDE Protein
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Influence of Pt/Ru anodic ratio on the valorization of ethanol by PEM electrocatalytic reforming towards value-added products 被引量:2
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作者 Alberto Rodriguez-Gomez Fernando Dorado +1 位作者 Antonio de Lucas-Consuegra Ana Raquel de la Osa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期264-275,共12页
The ethanol electro-reforming process was studied over PtRu/C catalysts synthesized by the modified polyol method with different compositions.In particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1... The ethanol electro-reforming process was studied over PtRu/C catalysts synthesized by the modified polyol method with different compositions.In particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1 and 1:2)on the organic product distribution(acetaldehyde,acetic acid and ethyl acetate)and pure hydrogen generation at different current densities operation levels.Physicochemical characterization of the catalysts was made by X-ray diffraction(XRD),temperature-programmed reduction(TPR)and N_(2) adsorption-desorption measurements.XRD patterns showed that Ru is introduced into the Pt structure,forming an alloy between both metals.Also,the degree of alloy was higher by increasing the Ru amounts.From TPR profiles Pt was found to be properly reduced while Ru was both in metallic state and forming RuO2.The electrochemical behaviour of each catalyst towards ethanol electroreforming process was investigated through electrochemical techniques in a half cell and a single proton exchange membrane(PEM)cell systems.An intermediate Pt:Ru ratio was found to result in high current density and electrochemical surface area(ECSA)values along with lower amounts of adsorbed species.Also,Ru addition seems to diminish the degree of degradation of the catalyst.Based on characterization and in agreement with essays carried out in a PEM cell at mild conditions(80℃ and 1 atm),PtRu/C 2:1 anode provided the best electrocatalytic results in terms of current density(740 mA cm^(-2)),hydrogen production and selectivity toward acetic acid(up to 15%apart from acetaldehyde and ethyl acetate)while requiring the lowest energy consumption. 展开更多
关键词 Ethanol electro-reforming PEM cell Pt:Ru anodic ratio Hydrogen production value-added liquid product distribution
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基于ISM-AHP-Entropy航空公司风险因素研究
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作者 罗凤娥 徐勇 +1 位作者 卫昌波 杜裕鑫 《航空计算技术》 2024年第2期26-31,共6页
针对航空公司风险因素研究,引入ISM-AHP-Entropy综合评价方法对风险因素进行评价。构建了风险因素指标体系,利用解析结构模型(ISM)将因素指标分为表层和深层致因,构建结构模型;根据问卷结果,用AHP-Entropy求出综合权重,结果表明人因和... 针对航空公司风险因素研究,引入ISM-AHP-Entropy综合评价方法对风险因素进行评价。构建了风险因素指标体系,利用解析结构模型(ISM)将因素指标分为表层和深层致因,构建结构模型;根据问卷结果,用AHP-Entropy求出综合权重,结果表明人因和管理因素对风险影响最为显著;进一步运用AHP-Entropy综合法分别计算表层和深层致因权重并分析,结果表明表层致因中机组资源管理水平、签派员应急处置能力影响最为显著,深层致因中安全规章方针的制定情况、应急管理培训与实施情况影响最为显著;从多个现实角度出发,结合CBTA理念,为航空公司降低风险、提高安全意识与水平提出多条建议,可供航空公司参考采纳。 展开更多
关键词 交通工程 航空公司风险因素 层次分析法 熵值法 解释结构模型
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Brief analysis on value-added tax transformation and its influence on enterprises
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作者 HUANG Wei-mo 《Chinese Business Review》 2009年第2期55-58,共4页
From Jan. 1st, 2009, the value-added tax transformation will be performed in all industries around the country. Based on value-added tax types and retrospection of reform practices, this article analyzes the backgroun... From Jan. 1st, 2009, the value-added tax transformation will be performed in all industries around the country. Based on value-added tax types and retrospection of reform practices, this article analyzes the background of the national value-added tax transformation and points out the influence of full implementation of the value-added tax transformation on various enterprises. 展开更多
关键词 value-added tax value-added tax transformation production value-added tax consumption value-added tax
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On the thermodynamics of plasticity during quasi-isentropic compression of metallic glass 被引量:1
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作者 Kaiguo Chen Bo Chen +7 位作者 Yinan Cui Yuying Yu Jidong Yu Huayun Geng Dongdong Kang Jianhua Wu Yao Shen Jiayu Dai 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期74-89,共16页
Entropy production in quasi-isentropic compression (QIC) is critically important for understanding the properties of materials under extremeconditions. However, the origin and accurate quantification of entropy in thi... Entropy production in quasi-isentropic compression (QIC) is critically important for understanding the properties of materials under extremeconditions. However, the origin and accurate quantification of entropy in this situation remain long-standing challenges. In this work, a framework is established for the quantification of entropy production and partition, and their relation to microstructural change in QIC. Cu50Zr50is taken as a model material, and its compression is simulated by molecular dynamics. On the basis of atomistic simulation-informed physicalproperties and free energy, the thermodynamic path is recovered, and the entropy production and its relation to microstructural change aresuccessfully quantified by the proposed framework. Contrary to intuition, entropy production during QIC of metallic glasses is relativelyinsensitive to the strain rate ˙γ when ˙γ ranges from 7.5 × 10^(8) to 2 × 10^(9)/s, which are values reachable in QIC experiments, with a magnitudeof the order of 10^(−2)kB/atom per GPa. However, when ˙γ is extremely high (>2 × 10^(9)/s), a notable increase in entropy production rate with˙γ is observed. The Taylor–Quinney factor is found to vary with strain but not with strain rate in the simulated regime. It is demonstrated thatentropy production is dominated by the configurational part, compared with the vibrational part. In the rate-insensitive regime, the increase inconfigurational entropy exhibits a linear relation to the Shannon-entropic quantification of microstructural change, and a stretched exponential relation to the Taylor–Quinney factor. The quantification of entropy is expected to provide thermodynamic insights into the fundamentalrelation between microstructure evolution and plastic dissipation. 展开更多
关键词 entropy METALLIC REGIME
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基于Dematel-Entropy耦合赋权的煤层顶板富水性评价 被引量:1
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作者 杜明启 徐杰 +2 位作者 吴慧杰 王启庆 李文平 《煤炭技术》 CAS 2024年第8期154-159,共6页
矿井的安全问题一直是矿业领域关注的重点,而准确评估含水层的富水性是进行涌水或突水灾害风险分析的首要前提。以大南湖七号煤矿一、二分区3煤顶板为研究对象,首先,在分析采区的地质及水文地质条件的基础上,选取了含水层厚度、隔水指... 矿井的安全问题一直是矿业领域关注的重点,而准确评估含水层的富水性是进行涌水或突水灾害风险分析的首要前提。以大南湖七号煤矿一、二分区3煤顶板为研究对象,首先,在分析采区的地质及水文地质条件的基础上,选取了含水层厚度、隔水指数、煤层倾角、岩心采取率、砂泥互层指数、岩性结构指数6个因素作为评价富水性的主要指标;然后,采用Dematel(决策实验室法)-Entropy(熵值法)确定主客观权重,利用信息熵原理协调2种评价方法之间既竞争又一致的关系,得到各影响因素组合权重;最后,结合GIS分析功能对含水层富水性进行评价分区。研究结果表明:一分区整体为弱富水性,二分区以中等-强富水性为主,评价结果准确率达80%以上,可为煤层顶板含水层的疏水方案提供参考。 展开更多
关键词 富水性 Dematel-entropy GIS 耦合赋权
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Evolution trends and structural decomposition of China's green value-added over 40 years of reform and opening-up
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作者 Jin Fan Wei Wan +1 位作者 Xiaohui Yuan Fatemeh Ranaei 《Chinese Journal of Population,Resources and Environment》 2020年第2期69-78,共10页
China's 40-year history of reform and opening-up includes rapid economic development as well as pollution and environmental governance.Using a four-stage division,this study explores the evolution trend and struct... China's 40-year history of reform and opening-up includes rapid economic development as well as pollution and environmental governance.Using a four-stage division,this study explores the evolution trend and structural decomposition of China's green value-added by constructing a non-competitive input-output table for environmental pollution from 1978 to 2017.The results indicate that pollution production coefficients increased continuously,and the green value-added index decreased.Additionally,the structural decomposition showed that investment and export were critical for economic growth during the period,though they were accompanied by serious pollution problems.The pollution generated by the raw material(represented by coal mining)and processing industries(represented by the textiles)were not controlled effectively.Pollution treatment for these industries should be strengthened in the future.The study has implications for government officials,policy makers,and academics.First,China should make green development a core concept for economic development,increase environmental pollution governance,develop a“green GDP,”incorporate the external costs of environmental pollution into the national economic accounting system.Second,it must change the investment and export structure as well as the traditional economic development pattern that exacerbates pollution.Specifically,the country should develop industries with low pollution and promote the export of industries producing high value-added products and increase green GDP per capita.Third,it should closely monitor the development of highly polluting industries.Upgrading technology to reduce pollution and strengthening pollution treatment will reduce the number of polluting industries and improve environmental governance efficiency. 展开更多
关键词 Green value-added Non-competitive input-output table Factor decomposition Environmental governance
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Reactive ball-milling synthesis of Co-Fe bimetallic catalyst for efficient hydrogenation of carbon dioxide to value-added hydrocarbons
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作者 Haipeng Chen Chenwei Wang +5 位作者 Mengyang Zheng Chenlei Liu Wenqiang Li Qingfeng Yang Shixue Zhou Xun Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期210-218,共9页
Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial chemicals.Herein,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-mi... Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial chemicals.Herein,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-milling method for highly active and selective hydrogenation of CO_(2) to value-added hydrocarbons.When reacted at 320℃,1.0 MPa and 9600 mL h^(-1) g_(cat)^(-1),the selectivity to light olefin(C_(2)^(=)-C_(4)^(=)) and C_(5)+ species achieves 57.3% and 22.3%,respectively,at a CO_(2) co nversion of 31.4%,which is superior to previous Fe-based catalysts.The CO_(2) activation can be promoted by the CoFe phase formed by reactive ball milling of the Fe-Co_(3)O_(4) mixture,and the in-situ Co_(2)C and Fe_(5)C_(2) formed during hydrogenation are beneficial for the C-C coupling reaction.The initial C-C coupling is related to the combination of CO species with the surface carbon of Fe/Co carbides,and the sustained C-C coupling is maintained by self-recovery of defective carbides.This new strategy contributes to the development of efficient catalysts for the hydrogenation of CO_(2) to value-added hydrocarbons. 展开更多
关键词 Reactive ball milling Co-Fe bimetallic catalyst Carbon dioxide value-added hydrocarbon C–C coupling reaction
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PoC: An IMS-based Wireless Value-added Service
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作者 Liu Xiaowen,Zhang Lijun (Department of Communication Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, China) 《ZTE Communications》 2005年第4期21-24,共4页
This article introduces the Push-to-talk over Cellular( PoC) service, a new mobile value-added service based on the IP Multimedia Subsystem (IMS). Its implementation scheme is discussed and its Session Initiation Prot... This article introduces the Push-to-talk over Cellular( PoC) service, a new mobile value-added service based on the IP Multimedia Subsystem (IMS). Its implementation scheme is discussed and its Session Initiation Protocol (SIP) signaling exchange flow is described. Target user groups are predicted based on the analysis of the strengths and weaknesses of the PoC service. The article purports that the PoC system could undoubtedly be used as a platform for new services such as multimedia messaging, instant messaging, presence, and picture receiving and sending. Just like the short message service, the PoC service will help the terminal vendors, equipment vendors, content providers and operators setup a win-for-all industrial value chain. 展开更多
关键词 IMS FIGURE POC An IMS-based Wireless value-added Service GPP Server UMTS
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Estimation of the anisotropy of hydraulic conductivity through 3D fracture networks using the directional geological entropy 被引量:1
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作者 Chuangbing Zhou Zuyang Ye +2 位作者 Chi Yao Xincheng Fan Feng Xiong 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期137-148,共12页
With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directi... With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directional entropic scale is used to measure the anisotropy of spatial order in different directions.Compared with the traditional connectivity indexes based on the statistics of fracture geometry,the directional entropic scale is capable to quantify the anisotropy of connectivity and hydraulic conductivity in heterogeneous 3D fracture networks.According to the numerical analysis of directional entrogram and fluid flow in a number of the 3D fracture networks,the hydraulic conductivities and entropic scales in different directions both increase with spatial order(i.e.,trace length decreasing and spacing increasing)and are independent of the dip angle.As a result,the nonlinear correlation between the hydraulic conductivities and entropic scales from different directions can be unified as quadratic polynomial function,which can shed light on the anisotropic effect of spatial order and global entropy on the heterogeneous hydraulic behaviors. 展开更多
关键词 3D fracture network Geological entropy Directional entropic scale ANISOTROPY Hydraulic conductivity
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Boron-doped high-entropy oxide toward high-rate and long-cycle layered cathodes for wide-temperature sodium-ion batteries 被引量:1
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作者 Yuzhen Dang Zhe Xu +8 位作者 Yurong Wu Runguo Zheng Zhiyuan Wang Xiaopin Lin Yanguo Liu Zheng-Yao Li Kai Sun Dongfeng Chen Dan Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期577-587,I0012,共12页
03-type layered metal oxides hold great promise for sodium-ion batteries cathodes owing to their energy density advantage.However,the severe irreversible phase transition and sluggish Na^(+)diffusion kinetics pose sig... 03-type layered metal oxides hold great promise for sodium-ion batteries cathodes owing to their energy density advantage.However,the severe irreversible phase transition and sluggish Na^(+)diffusion kinetics pose significant challenges to achieve high-performance layered cathodes.Herein,a boron-doped03-type high entropy oxide Na(Fe_(0.2)Co_(0.15)Cu_(0.05)Ni_(0.2)Mn_(0.2)Ti_(0.2))B_(0.02)O_(2)(NFCCNMT-B_(0.02))is designed and the covalent B-O bonds with high entropy configuration ensure a robust layered structure.The obtained cathode NFCCNMT-B_(0.02)exhibits impressive cycling performance(capacity retention of 95%and 82%after100 cycles and 300 cycles at 1 and 10 C,respectively)and outstanding rate capability(capacity of 83 mAh g^(-1)at 10 C).Furthermore,the NFCCNMT-B_(0.02)demonstrates a superior wide-temperature performance,maintaining the same capacity level(113,4 mAh g^(-1)@-20℃,121 mAh g^(-1)@25℃,and 119 mAh g^(-1)@60℃)and superior cycle stability(90%capacity retention after 100 cycles at 1 C at-20℃).The high-entropy configuration design with boron doping strategy contributes to the excellent sodium-ion storage performance.The high-entropy configuration design effectively suppresses irreversible phase transitions accompanied by small volume changes(ΔV=0.65 A3).B ions doping expands the Na layer distance and enlarges the P3 phase region,thereby enhancing Na^(+)diffusion kinetics.This work offers valuable insights into design of high-performance layered cathodes for sodium-ion batteries operating across a wide temperature. 展开更多
关键词 High entropy oxide Born substitution Phase transition Na~+diffusion kinetics Sodium-ion batteries
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Export Value-Added of China’s Manufacturing Sector:Estimation and Mechanism Analysis
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作者 樊秀峰 程文先 《China Economist》 2015年第6期66-77,共12页
Estimation of domestic and overseas value-added of manufacturing sector is an important and difficult subject for the science-based evaluation of a country's trade interests under global value chain. Traditional HIY ... Estimation of domestic and overseas value-added of manufacturing sector is an important and difficult subject for the science-based evaluation of a country's trade interests under global value chain. Traditional HIY approach overestimates the domestic value- added of export. Although Koopman's method made certain improvements, it cannot utilize traditional I/O matrix and direct input coefficient matrix under the condition of incomplete information. By creating GAMS model, this paper addresses the above-mentioned problems and employs an improved model for the estimation of variations in domestic and overseas value-added of Chinese exports between 2002 and 2012. Our results indicate that by neglecting the export of processing trade, HIY approach overestimates the domestic value- added ratio of Chinese exports. As more imported intermediate inputs have been used in the export of processing trade, the estimation result of this paper have corrected deviations in the forecast of overseas value-added ratio and its tendencies based on HIY method Further analysis of specific factors of domestic value-added of export led to the discovery that the domestic value-added of export of processing trade and mixed trade is highly vulnerable to the impact of international capital inflow. It can be seen that the improved method for the estimation of value-added has indeed corrected the deviations in the estimation of China's value-added. In conclusion, China should accelerate the development of export of non- processing trade and trade in high-end services, and balance the relationship of export between local firms and foreign-funded firms, with a view to improving trade dependence and increasing the trade status of Chinese manufaeturing firms in global value chain. 展开更多
关键词 global value chain domestic value-added processing trade estimationapproach
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Microstructure and Properties of AlCoCrFeNiTi High-Entropy Alloy Coatings Prepared by Laser Cladding 被引量:1
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作者 Mengxian Li Zhiping Sun +1 位作者 Zhaomin Xu Zhiming Wang 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第2期50-61,共12页
21-4N(5Cr21Mn9Ni4N)is extensively employed in the production of engine valves,operating under severe conditions.Apart from withstanding high-temperature gas corrosion,it must also endure the impact of cylinder explosi... 21-4N(5Cr21Mn9Ni4N)is extensively employed in the production of engine valves,operating under severe conditions.Apart from withstanding high-temperature gas corrosion,it must also endure the impact of cylinder explosion pressure.The predominant failure mode of 21-4N valves is abrasive wear.Surface coatings serve as an effective approach to prevent such failures.In this investigation,Laser cladding technology was utilized to fabricate AlCoCrFeNiTi high entropy alloy coatings onto the surfaces of 21-4N valves.According to the findings,the cladding zone has a normal dendritic microstructure,a good substrate-to-cladding layer interaction,and no obvious flaws.In terms of hardness,the cladding demonstrates an average hardness of 620 HV.The hardness has increased by 140%compared to the substrate.The average hardness of the cladding remains at approximately 520 HV even at elevated temperatures.Regarding frictional wear performance,between 400℃and 800℃,the cladding layer exhibits an average friction coefficient of 0.4,with the primary wear mechanisms being abrasive wear,adhesive wear,and a minor degree of plastic deformation. 展开更多
关键词 high entropy alloy laser cladding MICROSTRUCTURE microstructure and properties
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International Competitiveness of China’s Manufacturing Sectors:Estimation Based on Trade in Value-added
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作者 戴翔 《China Economist》 2015年第6期110-122,共13页
Based on trade in value-added, this paper has estimated the revealed comparative advantage (RCA) of China's various manufacturing sectors between 1995 and 2011 and compared with the RCA indexes measured using conve... Based on trade in value-added, this paper has estimated the revealed comparative advantage (RCA) of China's various manufacturing sectors between 1995 and 2011 and compared with the RCA indexes measured using conventional aggregate accounting approach. Results indicate that: (1) the RCA index measured using conventional aggregate accounting approach has underestimated China's comparative advantage of labor-intensive sectors but overestimated China's comparative advantage in capital, knowledge and technology-intensive manufacturing sectors, giving rise to a serious misjudgment. (2) The RCA measured using value-added approach shows that in the industry chain layout of global manufacturing sectors, China's comparative advantage is still concentrated in labor-intensive manufacturing sectors but has signs of weakening; in capital, knowledge and technology-intensive sectors, China is yet to develop any significant comparative advantage; there are signs that China is developing comparative advantage in capital-intensive sectors yet China's comparative disadvantage in knowledge and technology-intensive sectors has no significant tendency to improve. This result not only helps correct the misjudgment of China's competitiveness in manufacturing sectors based on conventional aggregate accounting approach but offers important policy implications for setting strategic directions and policies for China's manufacturing transition and upgrade. 展开更多
关键词 trade in value-added international competitiveness revealed comparativeadvantage (RCA)
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Distribution of Value-added Income of Collective Construction Land Entering the Market Based on the Subject Input Contribution and TOPSIS
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作者 Chenguang YUAN Lingchao WANG 《Asian Agricultural Research》 2021年第12期19-22,共4页
In order to promote the revitalization and development of rural areas and protect the property rights of farmers,it is necessary to explore the reasonable distribution ratio of land value-added income in collective op... In order to promote the revitalization and development of rural areas and protect the property rights of farmers,it is necessary to explore the reasonable distribution ratio of land value-added income in collective operating construction land.Under the existing land value-added income distribution model,the land value-added income obtained by the government is much greater than that of village collectives,and it is difficult for village collectives and farmers to enjoy greater benefits.This distribution model is not conducive to protecting the property rights of farmers.The results show that there was a positive correlation between land value-added income and land level,that is,the higher the land level was,the higher the value-added income and its ratio to the market transaction price were.According to calculation,the reasonable distribution ratio of the value-added income of collective operating construction land entering the market among the government,village collectives and farmers was 28.6%,51.1%,and 20.3%respectively.The actual land value-added income obtained by farmers was greatly improved compared with the current situation.In actual operation,this distribution mode has universal applicability.The reform of entering the market in the future also needs to raise the standards for entering the market,explore diversified interest protection channels,and strengthen the construction of rural collective management system. 展开更多
关键词 Collective operating construction land Land value-added income Subject input contribution TOPSIS
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