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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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Collaborative Innovation:A Strategic Pathway to Higher Domestic Value-added in Manufacturing Exports
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作者 Li Zexin Liu Qing Zhao Zhongxiu 《China Economist》 2025年第2期50-69,共20页
International trade research has long sought to investigate how manufacturers can upgrade within global value chains and escape the“low-end trap”.This paper examines how collaborative innovation can facilitate this ... International trade research has long sought to investigate how manufacturers can upgrade within global value chains and escape the“low-end trap”.This paper examines how collaborative innovation can facilitate this ascent,using an undirected weighted network of joint patent applications and firm-level data.By analyzing the network’s structural characteristics and its evolution,we explore the mechanisms through which collaboration drives the rise of manufacturing enterprises within global value chains.Our findings show that:(1)China’s rapidly expanding collaborative innovation network features a distinct“core-periphery”structure,with leading firms,universities,and government research institutions at its center.(2)By strengthening market power and enabling firms to take on more advanced production,collaborative innovation contributes to a higher domestic value-added rate in exports.(3)Heterogeneity analysis reveals that the impact of collaborative innovation on moving up the value chain is particularly evident for firms with strong production and technology absorption capabilities,those positioned lower in the value chain,and those facing fewer trade barriers. 展开更多
关键词 Global value chain(GVC) domestic value-added rate of exports collaborative innovation innovation network
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Research on the Construction and Practice of an Evidence-Based Value-Added Evaluation System Based on Data-Driven 被引量:1
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作者 Lingduo Yang Lili Xu +2 位作者 Yan Xu Furong Peng Shuai Zhang 《Journal of Contemporary Educational Research》 2025年第5期61-67,共7页
Based on the educational evaluation reform,this study explores the construction of an evidence-based value-added evaluation system based on data-driven,aiming to solve the limitations of traditional evaluation methods... Based on the educational evaluation reform,this study explores the construction of an evidence-based value-added evaluation system based on data-driven,aiming to solve the limitations of traditional evaluation methods.The research adopts the method of combining theoretical analysis and practical application,and designs the evidence-based value-added evaluation framework,which includes the core elements of a multi-source heterogeneous data acquisition and processing system,a value-added evaluation agent based on a large model,and an evaluation implementation and application mechanism.Through empirical research verification,the evaluation system has remarkable effects in improving learning participation,promoting ability development,and supporting teaching decision-making,and provides a theoretical reference and practical path for educational evaluation reform in the new era.The research shows that the evidence-based value-added evaluation system based on data-driven can reflect students’actual progress more fairly and objectively by accurately measuring the difference in starting point and development range of students,and provide strong support for the realization of high-quality education development. 展开更多
关键词 DATA-DRIVEN Evidence-based evaluation value-added evaluation Large model Educational evaluation reform
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Research on the Current Situation,Problems,and Solution Paths of Value-Added Evaluation for Vocational College Students in the Context of Big Data
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作者 Jing Zhang Lili Xu Shuai Zhang 《Journal of Contemporary Educational Research》 2025年第7期280-285,共6页
Value-added evaluation focuses on individual student growth by tracking changes in academic performance,skills,literacy,etc.,at different time points.It weakens horizontal comparisons and emphasizes vertical progress ... Value-added evaluation focuses on individual student growth by tracking changes in academic performance,skills,literacy,etc.,at different time points.It weakens horizontal comparisons and emphasizes vertical progress to more fairly reflect educational effectiveness.This evaluation method is particularly suitable for vocational education,effectively motivating students’learning enthusiasm and enhancing their self-confidence.Foreign research is represented by the Tennessee Value-Added Assessment System(TVAAS),widely used in evaluating school quality and teacher performance.Domestic research currently focuses on the theoretical construction,model establishment,optimization,and practical application of value-added evaluation,still facing significant challenges in data collection comprehensiveness and model adaptability.Aiming at current issues,this study focuses on exploring the application of artificial intelligence large models in student value-added evaluation from an evidence-based perspective,committed to constructing an innovative evidence-based value-added evaluation system.It aims to achieve precise assessment of students’learning effect“net value-added”through multi-source data collection,intelligent analysis,and personalized feedback.The system integrates outcome evaluation,process evaluation,value-added evaluation,and comprehensive evaluation to form a“four-in-one”dynamic evaluation framework,considering students’starting points,process performance,and final achievements.In the future,value-added evaluation needs to further expand the assessment of non-academic dimensions(such as professional literacy and social-emotional skills)and explore the application of non-linear models to promote the deepening and innovation of educational evaluation reform. 展开更多
关键词 EVIDENCE-BASED value-added evaluation Artificial intelligence Large model Intelligent agent
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Electrosynthesis of value-added chemicals:Challenges from laboratory research to industrial application
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作者 Li-Li Zhang Zhen Zhou 《Chinese Journal of Catalysis》 2025年第6期1-7,共7页
Electrochemical synthesis of value-added chemicals represents a promising approach to address multidisciplinary demands.This technology establishes direct pathways for electricity-to-chemical conversion while signific... Electrochemical synthesis of value-added chemicals represents a promising approach to address multidisciplinary demands.This technology establishes direct pathways for electricity-to-chemical conversion while significantly reducing the carbon footprint of chemical manufacturing.It simultaneously optimizes chemical energy storage and grid management,offering sustainable solutions for renewable energy utilization and overcoming geographical constraints in energy distribution.As a critical nexus between renewable energy and green chemistry,electrochemical synthesis serves dual roles in energy transformation and chemical production,emerging as a vital component in developing carbon-neutral circular economies.Focusing on key small molecules(H_(2)O,CO_(2),N_(2),O_(2)),this comment examines fundamental scientific challenges and practical barriers in electrocatalytic conversion processes,bridging laboratory innovations with industrial-scale implementation. 展开更多
关键词 ELECTROSYNTHESIS Hydrogen energy value-added chemicals Energy conversion Reaction engineering
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Profitability Analysis of Various Maize Value-Added Products in the North-West Region of Cameroon
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作者 Ngala Nadege Muyu Bime Mary Juliet Egwu +2 位作者 Mbu Daniel Tambi Chefor Fotang Kum Rene Ebua 《Agricultural Sciences》 2025年第1期161-177,共17页
Maize value-added products play a crucial role in reducing post-harvest losses, enhancing food security, and generating income. While extensive research has focused on maize production in Cameroon, the exploration of ... Maize value-added products play a crucial role in reducing post-harvest losses, enhancing food security, and generating income. While extensive research has focused on maize production in Cameroon, the exploration of its value-added products and their profitability in the North-West Region remains underexplored. This study examined the profitability of maize value-added products in Mezam Division, with the objectives to: 1) identify various maize-based products, 2) assess the diversity of these products, 3) conduct a cost-benefit analysis of selected products, 4) examine the relationship between profitability and product diversity, and 5) identify key constraints impacting profitability. To achieve these objectives, structured questionnaires were administered to 500 small-scale maize entrepreneurs randomly selected from five subdivisions. Descriptive statistics were used to analyze objective 1 and 5, while the Shannon Diversity Index was employed to assess product diversity. Additionally, a cost-benefit analysis was conducted on four selected products namely pap, parched corn, peeled parboiled corn, and corn beer, and a correlation analysis was used to examine objective 4. In total, 13 maize value-added products were identified, with a diversity index of 4.4. The total cost of processing the four selected products per entrepreneur using 18 kg of maize per product was FCFA 83631.5 (US $132.75), while the total revenue was FCFA 121864.5 (US $193.43), resulting in an economic profit of FCFA 38,233 (US $60.69). Pap emerged as the most profitable product, with an economic profit of FCFA 27,875 (US $44.24), while corn beer was the least profitable, with an economic profit of FCFA 2133.46 (US $3.39). The correlation analysis revealed a strong negative relationship between product diversity and profitability (r = −0.91), indicating that entrepreneurs can maximize profitability by focusing on a few high-demand products like pap and parched corn. Key constraints to profitability included fluctuating market prices, high production costs, limited access to finance, and inadequate storage facilities. Despite these challenges, our findings indicate that maize value addition is profitable in Mezam Division. Entrepreneurs can leverage this data for informed decision-making and future investments. It is recommended that the government promote maize value addition and provide financial support for modern processing equipment to boost profitability and income generation. 展开更多
关键词 MAIZE Maize value-added Products Cost-Benefit Analysis Economic Profits
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Distribution of Value-added Income of Rural Land Collective Ownership
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作者 Bing ZHAN 《Asian Agricultural Research》 2025年第2期27-29,共3页
In the context of urban-rural integration development in China,the distribution of value-added income of rural land collective ownership is related to the protection of farmers rights and interests and the specific im... In the context of urban-rural integration development in China,the distribution of value-added income of rural land collective ownership is related to the protection of farmers rights and interests and the specific implementation of rural revitalization strategy.Based on the entry of rural collectively-owned construction land into the market and the compensation system for land expropriation,this paper discusses in detail the distribution of value-added income of rural land collective ownership,analyzes the current situation,existing problems and causes of the current distribution mechanism,and puts forward countermeasures and suggestions for optimizing the distribution mechanism.Through literature research and case analysis,this paper reveals the unfair phenomenon in the distribution of value-added income of rural land,and discusses the roles and responsibilities of government,collective organizations and individual farmers in the distribution of income.The results show that establishing a fair and reasonable income distribution mechanism,strengthening the construction of laws and regulations,improving farmers participation and protecting their rights and interests are the key to optimizing the distribution of rural land value-added income.In addition,it is expected that this paper will provide some theoretical basis and practical guidance for improving the distribution mechanism of value-added income of rural land collective ownership. 展开更多
关键词 Collective land ownership Distribution of value-added income Farmers rights and interests Urban-rural integration Rural revitalization
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Indoor smart farming by inducing artificial climate for high value-added crops in optimal duration 被引量:1
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作者 Attique ur Rehman Abdul Razzaq +5 位作者 Adnan Altaf Salman Qadri Aamir Hussain Ali Nawaz Khan Tausif-ur-Rehman Zaid Sarfraz 《International Journal of Agricultural and Biological Engineering》 SCIE 2023年第3期240-246,共7页
The global population is increasing rapidly as compared to food production;approximately three times more food would be required in 2050.Climate change affects crop production by causing sudden changes in weather cond... The global population is increasing rapidly as compared to food production;approximately three times more food would be required in 2050.Climate change affects crop production by causing sudden changes in weather conditions,including rain,storms,heat waves,doughiness,and water shortages.Farming with smart technology provides a productive solution.Smart farming is a productive solution that provides a great resource of income and improves the countries’economy by exporting consumable goods and preventing food security problems.Smart agriculture provides a combination of flexibility,remote access,and automation through the use of intelligent control technologies.Many countries are working towards smart and intelligent agriculture farming that analyzes crop,soil fertility,pests and weeds,and other problems caused by mismanagement and incompetence.However,smart agricultural farming is less widely adopted in agriculture as a result of high costs and little understanding of technology.In this study,An artificial climate control chamber(ACCC)was designed for cultivating plants by controlling the optimal parameters,especially the light spectrum.In ACCC,influential plant factors such as light,moisture,humidity,and fertilizer concentration have been controlled intelligently.Light spectrum was controlled by time periods in the previous system,while in the system proposed in this study,the light was controlled by image processing.In an artificial control chamber,the plant growth stages have been determined through image processing techniques.Datasets of image images have been used to organize specific intensities of the light spectrum.This intelligent system provides aid in the speed breeding procedure through variant spectrums of light and fertilizers combinations.In the research study,the yield and quality of intelligent farming are enhanced. 展开更多
关键词 indoor smart farming artificial climate high value-added crops optimal duration light spectrum image processing
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Upcycling plastic wastes into value-added products via electrocatalysis and photoelectrocatalysis 被引量:5
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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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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:7
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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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Geomorphology-oriented theoretical framework and construction method for value-added DEM 被引量:2
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作者 ZHANG Haiping TANG Guoan +2 位作者 XIONG Liyang YANG Xin LI Fayuan 《Journal of Geographical Sciences》 SCIE CSCD 2024年第1期165-184,共20页
Digital elevation model(DEM)plays a fundamental role in the study of the earth system by expressing surface configuration,understanding surface process,and revealing surface mechanism.DEM is widely used in analysis an... Digital elevation model(DEM)plays a fundamental role in the study of the earth system by expressing surface configuration,understanding surface process,and revealing surface mechanism.DEM is widely used in analysis and modeling in the field of geoscience.However,traditional DEM has the defect of single attribute,which is difficult to support the research in earth system science oriented to geoscience process and mechanism mining.Hence,realizing the value-added data model on the basis of traditional DEM is necessary to serve digital elevation modeling and terrain analysis under the background of a new geomorphology research paradigm and earth observation technology.A theoretical framework for value-added DEM that mainly includes concept,connotation,content,and categories,is constructed in this study.The relationship between different types of value-added DEMs as well as the research significance and application category of this theoretical framework are also proposed.The following are different methods of value-added DEMs:(1)value-added methods of DEM space and time dimensions that emphasize the integration of the ground and underground as well as coupling of time and space,(2)attribute-based value-added methods composed of material(including underground,surface,and ground)and morphological properties,and(3)value-added methods of features and physical elements that consider geographical objects and landform features formed by natural processes and artificial effects.The digital terrace,slope,and watershed models are used as examples to illustrate application scenarios of the three kinds of value-added methods.This study aims to improve expression methods of DEMs under the background of new surveying and mapping technologies by adding value to the DEM at three levels of dimensions,attributes,and elements as well as support knowledge-driven digital geomorphological analysis in the era of big data. 展开更多
关键词 spatial data model value-added DEM digital terrain analysis geomorphological ontology GEOMORPHOLOGY
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A direct polymeric carbon nitride/tungsten oxide Z-scheme heterostructure for efficient photocatalytic hydrogen generation via reforming of plastics into value-added chemicals 被引量:2
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作者 Rui-Zhe Wang Zhi Lin +5 位作者 Yi-Qing Wang Kai-Ni Zhang Ge-Hong Zhang Jie Zhang Samuel S.Mao Shao-Hua Shen 《Rare Metals》 SCIE EI CAS CSCD 2024年第8期3771-3783,共13页
To promote charge transfer and separation for efficient photocatalysis,a direct Z-scheme heterostructure was constructed by coupling polymeric carbon nitride(PCN) and WO_(3).Interestingly,the obtained PCN/WO_(3)Z-sche... To promote charge transfer and separation for efficient photocatalysis,a direct Z-scheme heterostructure was constructed by coupling polymeric carbon nitride(PCN) and WO_(3).Interestingly,the obtained PCN/WO_(3)Z-scheme heterostructure could photocataly tic ally produce hydrogen and value-added chemicals(e.g.,formate and acetate) by reforming of plastic polylactic acid(PLA) in alkaline aqueous condition.By optimizing WO_(3) contents and reaction conditions,the obtained PCN/WO_(3)heterostructure exhibits much increased photocatalytic activity for PLA photoreforming under visible light,with hydrogen evolution rate reaching 402.90 μmol·g~(-1)·h~(-1),which is 3.5 times that of PCN.It is revealed that the Z-scheme charge transfer between PCN and WO_(3) mainly contributes to the promoted charge separation and thus the improved photocatalytic activity.Moreover,with h+and·OH experimentally evidenced as the predominant active species,a possible reaction pathway for the reforming of PLA into value-added chemicals(e.g.,formate and acetate)over PCN/WO_(3) Z-scheme heterostructure is cleared by monitoring the reaction intermediates and radicals.This work paves a carbon neutrality and scalable route toward the synergistical production of hydrogen and value-added chemicals by utilizing and recycling plastic waste. 展开更多
关键词 Carbon nitride Z-scheme heterojunction Plastic waste conversion Photocatalytic H_(2)production value-added chemicals
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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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Research on Improving Value-Added Processing of Jaboticaba
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作者 Chinghu Tsai Tachih Liu +1 位作者 Yichun Lin Yoju Chen 《Food and Nutrition Sciences》 2024年第12期1334-1344,共11页
This research will use food fermentation technology and supercritical extraction technology to enhance the value-added application of the active ingredients of Jaboticaba. The results showed that the bioactive compone... This research will use food fermentation technology and supercritical extraction technology to enhance the value-added application of the active ingredients of Jaboticaba. The results showed that the bioactive component content of samples after value-added fermentation and extraction was 19.86% to 69.30% higher than that of fresh fruit. In the analysis of antioxidant activity, it was found that the ability to scavenge free radicals was higher than that of fresh fruits. The total antioxidant activity and reducing power were best after fermentation and supercritical extraction, reaching more than 90%. After fermentation, the active ingredients were detected, and the resveratrol content was 3.27 mg/L, the anthocyanin content was 67.71 mg/g, and the tryptophan content was 0.48 gm/Kg, all of which were higher than those in fresh fruits. The results of this research are helpful for the development of natural anti-inflammatory or sleep-aiding products. It is of great significance for the research on anti-inflammatory and sleep-aiding. It can also provide value-added processing conditions to solve the problem of Jiabao fruit during the peak production season. The pressure of excessive production and processing will increase the value-added economy of the industry and make Jaboticaba more valuable for research. 展开更多
关键词 value-added Jaboticaba Supercritical Extraction ANTIOXIDANT Sleep Aid
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A high entropy stabilized perovskite oxide La_(0.2)Pr_(0.2)Sm_(0.2)Gd_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)O_(3−δ)as a promising air electrode for reversible solid oxide cells 被引量:1
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作者 LI Ruoyu LI Xiaoyu +2 位作者 ZHANG Jinke GAO Yuan LING Yihan 《燃料化学学报(中英文)》 北大核心 2025年第2期282-290,共9页
Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage p... Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage poses challenges for the performance and stability of air electrodes.In this work,a novel high-entropy perovskite oxide La_(0.2)Pr_(0.2)Gd_(0.2)Sm_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)O_(3−δ)(HE-LSCF)is proposed and investigated as an air electrode in RSOC.The electrochemical behavior of HE-LSCF was studied as an air electrode in both fuel cell and electrolysis modes.The polarization impedance(Rp)of the HE-LSCF electrode is only 0.25Ω·cm^(2) at 800℃ in an air atmosphere.Notably,at an electrolytic voltage of 2 V and a temperature of 800℃,the current density reaches up to 1.68 A/cm^(2).The HE-LSCF air electrode exhibited excellent reversibility and stability,and its electrochemical performance remains stable after 100 h of reversible operation.With these advantages,HE-LSCF is shown to be an excellent air electrode for RSOC. 展开更多
关键词 reversible solid oxide cell high entropy stabilized perovskite air electrode electrochemical performance
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Research on multi-scale simulation and dynamic verification of high dynamic MEMS components in additive manufacturing 被引量:1
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作者 Sining Lv Hengzhen Feng +2 位作者 Wenzhong Lou Chuan Xiao Shiyi Li 《Defence Technology(防务技术)》 2025年第5期275-291,共17页
Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects s... Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects such as porosity issues, significant deformation, surface cracks, and challenging control of surface morphology encountered during the selective laser melting(SLM) additive manufacturing(AM) process of specialized Micro Electromechanical System(MEMS) components, multiparameter optimization and micro powder melt pool/macro-scale mechanical properties control simulation of specialized components are conducted. The optimal parameters obtained through highprecision preparation and machining of components and static/high dynamic verification are: laser power of 110 W, laser speed of 600 mm/s, laser diameter of 75 μm, and scanning spacing of 50 μm. The density of the subordinate components under this reference can reach 99.15%, the surface hardness can reach 51.9 HRA, the yield strength can reach 550 MPa, the maximum machining error of the components is 4.73%, and the average surface roughness is 0.45 μm. Through dynamic hammering and high dynamic firing verification, SLM components meet the requirements for overload resistance. The results have proven that MEM technology can provide a new means for the processing of MEMS components applied in high dynamic environments. The parameters obtained in the conclusion can provide a design basis for the additive preparation of MEMS components. 展开更多
关键词 Additive manufacturing high dynamic MEMS components Multiscale control Process optimization high dynamic verification
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Improvement on Qm in high-power piezoelectric ceramics through[111]c texture engineering 被引量:1
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作者 Wenming Shi Hongjun Zhang +4 位作者 Yingchun Liu Lang Bian Wenjing Bi Yuanhao Deng Bin Yang 《Journal of Materials Science & Technology》 2025年第13期260-268,共9页
Improving mechanical quality factor Qm is of great significance for high-power applications.Here,a new strategy of the[111]c texture engineering was proposed to enhance the performances of high-power piezoelectric cer... Improving mechanical quality factor Qm is of great significance for high-power applications.Here,a new strategy of the[111]c texture engineering was proposed to enhance the performances of high-power piezoelectric ceramics.The 5 vol%BaTiO_(3)(BT)templates with the[111]c preferred orientation were in-troduced into matrix powders of 0.03 Pb(Mn_(1/3) Nb_(2/3))O_(3)-0.33Pb(Ni_(1/3) Nb_(2/3))O_(3)-0.28 PbZrO_(3)-0.36PbTiO_(3)(28PZ(R))to form the[111]c textured ceramics(28PZ(T)),possessing a texture degree of 74%.The mul-tiple of uniform density in EBSD increased from 0.63 in randomly oriented 28 PZ(R)to 6.63 in 28PZ(T).The good lattice matching between BT templates and textured grains was observed using high-resolution transmission electron microscopy,confirming the microscopic origin of the[111]c texture.The maximum phase angleθmax of 88.2°was quite near 90°in 28PZ(T),ensuring the optimal Qm value of 1275 and the great figure of merit of 255,000 pC/N.The increased Qm in[111]c texture ceramics was confirmed due to the reduced intrinsic polarization directions rather than the pinning effect of the internal bias field.Larger grain sizes with larger domains restrained the movement of domain walls in 28 PZ(T),which was also favorable to higher Qm.This work may provide a new promising route for further high-power applications. 展开更多
关键词 _(c)texture Texture process high Q_(m) high power CRYSTALLOGRAPHY
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Fast-zoom and high-resolution sparse compound-eye camera based on dual-end collaborative optimization 被引量:1
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作者 Yi Zheng Hao-Ran Zhang +5 位作者 Xiao-Wei Li You-Ran Zhao Zhao-Song Li Ye-Hao Hou Chao Liu Qiong-Hua Wang 《Opto-Electronic Advances》 2025年第6期4-15,共12页
Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution... Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution sparse compound-eye camera(CEC)based on dual-end collaborative optimization is proposed,which provides a cost-effective way to break through the trade-off among the field of view,resolution,and imaging speed.In the optical end,a sparse CEC based on liquid lenses is designed,which can realize large-field-of-view imaging in real time,and fast zooming within 5 ms.In the computational end,a disturbed degradation model driven super-resolution network(DDMDSR-Net)is proposed to deal with complex image degradation issues in actual imaging situations,achieving high-robustness and high-fidelity resolution enhancement.Based on the proposed dual-end collaborative optimization framework,the angular resolution of the CEC can be enhanced from 71.6"to 26.0",which provides a solution to realize high-resolution imaging for array camera dispensing with high optical hardware complexity and data transmission bandwidth.Experiments verify the advantages of the CEC based on dual-end collaborative optimization in high-fidelity reconstruction of real scene images,kilometer-level long-distance detection,and dynamic imaging and precise recognition of targets of interest. 展开更多
关键词 compound-eye camera ZOOM high resolution collaborative optimization
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High cycle fatigue performance at 650℃and corresponding fracture behaviors of GH4169 joint produced by linear friction welding 被引量:2
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作者 Shitong MA Xiawei YANG +6 位作者 Zhenguo GUO Yu SU Xinyuan HE Ju LI Jun TAO Bo XIAO Wenya LI 《Chinese Journal of Aeronautics》 2025年第1期622-637,共16页
GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 58... GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 582 MPa and 820 MPa,respectively.The HCF strength of joint reaches 400 MPa,which is slightly lower than that of Base Metal(BM),indicating reliable quality of this type of joint.The microstructure observation results show that all cracks initiate at the inside of specimens and transfer into deeper region with decrease of external stress,and the crack initiation site is related with microhardness of matrix.The Electron Backscattered Diffraction(EBSD)results of the observed regions with different distances to fracture show that plastic deformation plays a key role in HCF,and the Schmid factor of most grains near fracture exceeds 0.4.In addition,the generation of twins plays a vital role in strain concentration release and coordinating plastic deformation among grains. 展开更多
关键词 high cycle fatigue GH4169 superalloy Linear friction welding Fracture mechanism Microstructure evolution
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Tourmaline and Mica Chemistry of the Wangxianling Granitoids,South China:Implications for Petrogenesis of Highly Fractionated Granite 被引量:1
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作者 DUAN Xiaoxia WANG Ziyi +3 位作者 CHEN Bin ZHOU Lingli WANG Zhiqiang CHEN Yanjiao 《Acta Geologica Sinica(English Edition)》 2025年第3期789-805,共17页
Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites.This paper assessed those two processes using geochemistry of muscovite and tourmaline a... Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites.This paper assessed those two processes using geochemistry of muscovite and tourmaline and bulkrock chemistry of multi-phase Wangxianling granitoids,South China.Compositional variations suggest the coarse-grained muscovite granite is produced from fractional crystallization of the two-mica granite whereas the fine-grained muscovite granite represents a distinct magma pulse.Progressive fractionation of quartz,feldspar and biotite leads to elevated boron and aluminum content in melt which promoted muscovite and tourmaline to crystallize,which promotes two-mica granite evolving towards tourmaline-bearing muscovite granite.Fluid-melt-crystal interaction occurred at the magmatichydrothermal transitional stage and resulted in the textural and chemical zonings of tourmaline and muscovite in finegrained muscovite granite.The rims of both tourmaline and muscovite are characterized by the enrichment of fluid mobile elements such as Li,Mn,Cs and Zn and heavierδ^(11)B values of the tourmaline rims(-15.0‰to-13.6‰)compared to cores(-15.7‰to-14.3‰).Meanwhile,significant M-type REE tetrad effects(TE_(1,3)=1.07-1.18)and low K/Rb ratios(48-52)also correspond to fluid-melt-crystal interaction.This study shows zoned muscovite and tourmaline can be excellent tracers of fractional crystallization and late-stage fluid-melt-crystal interaction in highly evolved magmatic systems. 展开更多
关键词 TOURMALINE MUSCOVITE highly fractionated granite fluid-melt interaction South China
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