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Valence electronic engineering of superhydrophilic Dy-evoked Ni-MOF outperforming RuO_(2) for highly efficient electrocatalytic oxygen evolution
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作者 Zhiyang Huang Miao Liao +6 位作者 Shifan Zhang Lixia Wang Mingcheng Gao Zuyang Luo Tayirjan Taylor Isimjan Bao Wang Xiulin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期244-252,I0007,共10页
Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) performance.Herein,we introduce a novel strategy ... Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) performance.Herein,we introduce a novel strategy of dysprosium(Dy) doping,using the unique 4f orbitals of this rare earth element to enhance electrocatalytic activity of MOFs.Our method involves constructing Dy-doped Ni-MOF(Dy@Ni-MOF) nanoneedles on carbon cloth via a Dy-induced valence electronic perturbation approach.Experiments and density functional theory(DFT) calculations reveal that Dy doping can effectively modify the electronic structure of the Ni active centers and foster a strong electronic interaction between Ni and Dy.The resulting benefits include a reduced work function and a closer proximity of the d-band center to the Fermi level,which is conducive to improving electrical conductivity and promoting the adsorption of oxygen-containing intermediates.Furthermore,the Dy@Ni-MOF achieves superhydrophilicity,ensuring effective electrolyte contact and thus accelerating reaction kinetics,Ex-situ and in-situ analysis results manifest Dy_(2)O_(3)/NiOOH as the actual active species.Therefore,Dy@Ni-MOF shows impressive OER performance,significantly surpassing Ni-MOF.Besides,the overall water splitting device with Dy@NiMOF as an anode delivers a low cell voltage of 1.51 V at 10 mA cm^(-2) and demonstrates long-term stability for 100 h,positioning it as a promising substitute for precious metal catalysts. 展开更多
关键词 Dy@Ni-MOF Dy incorporation Electronic interaction SUPERHYDROPHILICITY Oxygen evolution reaction
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Structural Engineering of Anode Materials for Low-Temperature Lithium-Ion Batteries:Mechanisms,Strategies,and Prospects
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作者 Guan Wang Guixin Wang +2 位作者 Linfeng Fei Lina Zhao Haitao Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期169-195,共27页
The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical applications.Consequently,extensive efforts have been contribut... The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical applications.Consequently,extensive efforts have been contributed to explore novel anode materials with high electronic conductivity and rapid Li^(+)diffusion kinetics for achieving favorable low-temperature performance of LIBs.Herein,we try to review the recent reports on the synthesis and characterizations of low-temperature anode materials.First,we summarize the underlying mechanisms responsible for the performance degradation of anode materials at subzero temperatures.Second,detailed discussions concerning the key pathways(boosting electronic conductivity,enhancing Li^(+)diffusion kinetics,and inhibiting lithium dendrite)for improving the low-temperature performance of anode materials are presented.Third,several commonly used low-temperature anode materials are briefly introduced.Fourth,recent progress in the engineering of these low-temperature anode materials is summarized in terms of structural design,morphology control,surface&interface modifications,and multiphase materials.Finally,the challenges that remain to be solved in the field of low-temperature anode materials are discussed.This review was organized to offer valuable insights and guidance for next-generation LIBs with excellent low-temperature electrochemical performance. 展开更多
关键词 Low-temperature performance Anode materials Microstructural regulations Surface modifications
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Optimization of the Pretreatment of the Mixture of Cassava Peelings and Pineapple Fibers Using Response Surface Methodology and a Process Simulator for the Bioethanol Production
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作者 Paul Nestor Djomou Djonga George Elambo Nkeng +2 位作者 Madjoyogo Hervé Sirma Ahmat Tom Thierry Tchamba Tchuidjang 《Energy and Power Engineering》 2024年第2期79-96,共18页
The increase in oil prices and greenhouse gas emissions has led to the search for substitutes for fossil fuels. In Cameroon, the abundance of lignocellulosic resources is inherent to agricultural activity. Production ... The increase in oil prices and greenhouse gas emissions has led to the search for substitutes for fossil fuels. In Cameroon, the abundance of lignocellulosic resources is inherent to agricultural activity. Production of bioethanol remains a challenge given the crystallinity of cellulose and the presence of the complex. The pretreatment aimed to solubilize the lignin fraction and to make cellulose more accessible to the hydrolytic enzymes, was done using the organosolv process. A mathematical modeling was performed to point out the effect of the temperature on the kinetics of the release of the reducing sugars during the pretreatment. Two mathematical model was used, SAEMAN’s model and Response surface methodology. The first show that the kinetic parameters of the hydrolysis of the cellulose and reducing sugar are: 0.05089 min<sup>-1</sup>, 5358.1461 J·mol<sup>-1</sup>, 1383.03691 min<sup>-1</sup>, 51577.6100 J·mol<sup>-1</sup> respectively. The second model was used. Temperature is the factor having the most positive influence whereas, ethanol concentration is not an essential factor. To release the maximum, an organosolv pre-treatment of this sub-strate should be carried out at 209.08°C for 47.60 min with an ethanol-water ratio of 24.02%. Organosolv pre-treatment is an effective process for delignification of the lignocellulosic structure. 展开更多
关键词 BIOETHANOL Cassava Peeling Pineapple Fibers Organosolv Process and Optimization
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Process engineering in circular economy 被引量:3
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作者 Lothar Reh 《Particuology》 SCIE EI CAS CSCD 2013年第2期119-133,共15页
Driven by increasing global population and by growing demand for individual wealth, the consumption of energy and raw materials as well as the steadily growing CO2 concentration in atmosphere pose great challenges to ... Driven by increasing global population and by growing demand for individual wealth, the consumption of energy and raw materials as well as the steadily growing CO2 concentration in atmosphere pose great challenges to process engineering. This complex multi-scale discipline deals with the transformation of mass by energy to manifold products in different industrial fields under economical and ecological sus- tainable conditions. In growing circular economy, process engineering increasingly plays an important role in recovering valuable components from very diffuse material flows leaving the user stocks following widely variable time periods of use. As well it is engaged in thermal recovery of energy therefrom and in environmentally safe disposal of residual solid wastes whose recovery economically is not feasible. An efficient recovery of materials and energy following the laws of entropy is a must. A complex network of mass, energy, transportation and information flows has to be regarded with growing traded quantities of used goods even on global level. Important constraints in time, however, exist for a necessary realization of innovative new processes and communal mobility and industrial infrastructure on medium and large scale. Based on reasonable long term and highly reliable statistics from industrial organizations repre- senting steel and paper industry, some limits and trends of possible developments in processing of those industries with long recycling experience will be discussed. 展开更多
关键词 Perspective Process engineering Circular economy Stocks and flows Energy and material efficiency Multi-scale systems Preparation ENTROPY Time constraints Steel industry Paper industry
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Principles and strategies for green process engineering 被引量:2
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作者 Suojiang Zhang Hongyan He +3 位作者 Qing Zhou Xiangping Zhang Xingmei Lu Yuan Tian 《Green Chemical Engineering》 2022年第1期1-4,共4页
The evolution of human civilization is becoming increasingly synchronized with the development of science and technology. Every step toward advancement achieved by humans showcases our creativity and ability to realiz... The evolution of human civilization is becoming increasingly synchronized with the development of science and technology. Every step toward advancement achieved by humans showcases our creativity and ability to realize ideas in practice. However, due to human activities aimed at goal fulfillment, Mother Earth has undeniably undergone many irreversible changes, which in turn have negatively impacted the environment [1]. 展开更多
关键词 BECOMING IRREVERSIBLE advancement
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Reactive template-derived interfacial engineering of CoP/CoO heterostructured porous nanotubes towards superior electrocatalytic hydrogen evolution 被引量:1
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作者 Qixing Zhou Ruoxu Sun +7 位作者 Yiping Ren Run Tian Jun Yang Huan Pang Kai Huang Xinlong Tian Lin Xu Yawen Tang 《Carbon Energy》 SCIE CAS CSCD 2023年第1期194-205,共12页
The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive ut... The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive utilization of the heterointerface effect can endow the catalysts with remarkably boosted electrocatalytic performance due to the modified electronic state of active sites.Herein,we demonstrate deliberate crafting of CoP/CoO heterojunction porous nanotubes(abbreviated as CoP/CoO PNTs hereafter)using a self-sacrificial template-engaged strategy.Precise control over the Kirkendall diffusion process of the presynthesized cobalt–aspartic acid complex nanowires is indispensable for the formation of CoP/CoO heterostructures.The topochemical transformation strategy of the reactive templates enables uniform and maximized construction of CoP/CoO heterojunctions throughout all the porous nanotubes.The establishment of CoP/CoO heterojunctions could considerably modify the electronic configuration of the active sites and also improve the electric conductivity,which endows the resultant CoP/CoO PNTs with enhanced intrinsic activity.Simultaneously,the hollow and porous nanotube architectures allow sufficient accessibility of exterior/interior surfaces and molecular permeability,drastically promoting the reaction kinetics.Consequently,when used as HER electrocatalysts,the well-designed CoP/CoO PNTs show Pt-like activity,with an overpotential of only 61 mV at 10mA cm^(−2) and excellent stability in 1.0M KOH medium,exceeding those of the vast majority of the previously reported nonprecious candidates.Density functional theory calculations further substantiate that the construction of CoP/CoO heterojunctions enables optimization of the Gibbs free energies for water adsorption and H adsorption,resulting in boosted HER intrinsic activity.The present study may provide in-depth insights into the fundamental mechanisms of heterojunction-induced electronic regulation,which may pave the way for the rational design of advanced Earth-abundant electrocatalysts in the future. 展开更多
关键词 HETEROJUNCTION hydrogen evolution reaction porous nanotubes reactive template
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Atomic Cu Sites Engineering Enables Efficient CO_(2)Electroreduction to Methane with High CH_(4)/C_(2)H_(4)Ratio
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作者 Minhan Li Fangzhou Zhang +6 位作者 Min Kuang Yuanyuan Ma Ting Liao Ziqi Sun Wei Luo Wan Jiang Jianping Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期361-375,共15页
Electrochemical reduction of CO_(2)into high-value hydrocarbons and alcohols by using Cu-based catalysts is a promising and attractive technology for CO_(2)capture and utilization,resulting from their high catalytic a... Electrochemical reduction of CO_(2)into high-value hydrocarbons and alcohols by using Cu-based catalysts is a promising and attractive technology for CO_(2)capture and utilization,resulting from their high catalytic activity and selectivity.The mobility and accessibility of active sites in Cubased catalysts significantly hinder the development of efficient Cu-based catalysts for CO_(2)electrochemical reduction reaction(CO_(2)RR).Herein,a facile and effective strategy is developed to engineer accessible and structural stable Cu sites by incorporating single atomic Cu into the nitrogen cavities of the host graphitic carbon nitride(g-C_(3)N_(4))as the active sites for CO_(2)-to-CH_(4)conversion in CO_(2)RR.By regulating the coordination and density of Cu sites in g-C_(3)N_(4),an optimal catalyst corresponding to a one Cu atom in one nitrogen cavity reaches the highest CH_(4)Faraday efficiency of 49.04%and produces the products with a high CH_(4)/C_(2)H_(4)ratio over 9.This work provides the first experimental study on g-C_(3)N_(4)-supported single Cu atom catalyst for efficient CH_(4)production from CO_(2)RR and suggests a principle in designing highly stable and selective high-efficiency Cu-based catalysts for CO_(2)RR by engineering Cu active sites in 2D materials with porous crystal structures. 展开更多
关键词 CO_(2)RR Cu single-atom catalyst g-C_(3)N_(4) METHANE CH_(4)/C_(2)H_(4)ratio
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Closed-loop scheduling optimization strategy based on particle swarm optimization with niche technology and soft sensor method of attributes-applied to gasoline blending process
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作者 Jian Long Kai Deng Renchu He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第9期43-57,共15页
Gasoline blending scheduling optimization can bring significant economic and efficient benefits to refineries.However,the optimization model is complex and difficult to build,which is a typical mixed integer nonlinear... Gasoline blending scheduling optimization can bring significant economic and efficient benefits to refineries.However,the optimization model is complex and difficult to build,which is a typical mixed integer nonlinear programming(MINLP)problem.Considering the large scale of the MINLP model,in order to improve the efficiency of the solution,the mixed integer linear programming-nonlinear programming(MILP-NLP)strategy is used to solve the problem.This paper uses the linear blending rules plus the blending effect correction to build the gasoline blending model,and a relaxed MILP model is constructed on this basis.The particle swarm optimization algorithm with niche technology(NPSO)is proposed to optimize the solution,and the high-precision soft-sensor method is used to calculate the deviation of gasoline attributes,the blending effect is dynamically corrected to ensure the accuracy of the blending effect and optimization results,thus forming a prediction-verification-reprediction closed-loop scheduling optimization strategy suitable for engineering applications.The optimization result of the MILP model provides a good initial point.By fixing the integer variables to the MILPoptimal value,the approximate MINLP optimal solution can be obtained through a NLP solution.The above solution strategy has been successfully applied to the actual gasoline production case of a refinery(3.5 million tons per year),and the results show that the strategy is effective and feasible.The optimization results based on the closed-loop scheduling optimization strategy have higher reliability.Compared with the standard particle swarm optimization algorithm,NPSO algorithm improves the optimization ability and efficiency to a certain extent,effectively reduces the blending cost while ensuring the convergence speed. 展开更多
关键词 BLEND Optimization algorithm Neural networks Particle swarm optimization Mixed integer programming
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黄河流域煤炭-煤电-煤化工场地特征精准智能识别方法及应用
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作者 董霁红 王立兵 +4 位作者 冯晓彤 王蕾 刘峰 翟文 THOMAS Kienberger 《煤炭学报》 EI CAS CSCD 北大核心 2024年第2期1011-1024,共14页
黄河流域是“能源流域”,兼具生态环境治理和经济社会发展的重任,涉煤产业场地类型、数量及特征的精准智能识别是流域能源资源-低碳发展-生态保护的关键基础问题。研究融合多源数据与深度学习算法,从流域-基地-场地尺度对黄河流域13个... 黄河流域是“能源流域”,兼具生态环境治理和经济社会发展的重任,涉煤产业场地类型、数量及特征的精准智能识别是流域能源资源-低碳发展-生态保护的关键基础问题。研究融合多源数据与深度学习算法,从流域-基地-场地尺度对黄河流域13个大型煤电基地的煤基场地特征精准解析,获得煤电基地高精度、高质量的本底信息,提出一种实时实景智能识别涉煤产业空间特征的新方法。(1)筛选Google image、GF-6影像、Sentinel-2影像等多源数据,采集13个大型煤电基地煤基场地样本,构建煤炭场地(露天)、煤炭场地(井工)、煤电场地、煤化工场地4类数据集,涵盖21种样本类型。按照每种样本六面体设定6×10个样本,共计1 260个场地样本,分析得出最适样本数量-最高识别效率-最优识别模型的置信区间为80%~86%。(2)建立了煤基场地类型量化模型(Coal-based Site Classification Quantitative Model, CSCQM)和煤基场地范围特征模型(Coalbased Site Range Characteristic Model, CSRCM),模型平均精准度为0.837。明析了黄河流域涉煤产业场地本底信息,提出Google image底图叠加场地智能识别模型解算结果的高精度场地智能识别方法。(3)解析了流域神东煤炭-煤电产业集聚区精准本底数据,依据遥感生态指数(Remote Sensing Based Ecological Index,IRSE)分析,煤基场地分布2 km核心区地表生态质量受煤炭、煤电产业影响明显,5 km缓冲区则影响不明显,而8 km控制区基本不受煤炭、煤电产业影响,从而给出了“动态修复”与分区域、分阶段重点治理等低碳路径。(4)解析了流域宁东煤炭-煤电-煤化工产业集聚区精准本底数据,2022年煤炭场地17.81 km^(2)、占比34.1%,煤化工场地22.3 km^(2)、占比42.6%,煤电场地12.2 km^(2)、占比23.3%,煤化工场地>煤炭场地>煤电场地。进而采用PSR(Pressure-State-Response)模型得到风险管控综合得分53.93分,较2003年提高了27.2%。划分生态维护区、生产监测预警区、损毁修复重建区、其他调控区的分区管控模式。研究为涉煤产业煤基场地潜在污染控制、场地治理及区域生态修复提供技术方法与实践支撑。 展开更多
关键词 黄河流域 煤基场地 多源数据 AI模型 精准智能识别
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Speed and surface steepness affect internal tibial loading during running 被引量:1
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作者 Hannah Rice Markus Kurz +4 位作者 Patrick Mai Leon Robertz Kevin Bill Timothy R.Derrick Steffen Willwacher 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期118-124,共7页
Background:Internal tibial loading is influenced by modifiable factors with implications for the risk of stress injury.Runners encounter varied surface steepness(gradients)when running outdoors and may adapt their spe... Background:Internal tibial loading is influenced by modifiable factors with implications for the risk of stress injury.Runners encounter varied surface steepness(gradients)when running outdoors and may adapt their speed according to the gradient.This study aimed to quantify tibial bending moments and stress at the anterior and posterior peripheries when running at different speeds on surfaces of different gradients.Methods:Twenty recreational runners ran on a treadmill at 3 different speeds(2.5 m/s,3.0 m/s,and 3.5 m/s)and gradients(level:0%;uphill:+5%,+10%,and+15%;downhill:-5%,-10%,and-15%).Force and marker data were collected synchronously throughout.Bending moments were estimated at the distal third centroid of the tibia about the medial-lateral axis by ensuring static equilibrium at each 1%of stance.Stress was derived from bending moments at the anterior and posterior peripheries by modeling the tibia as a hollow ellipse.Two-way repeated-measures analysis of variance were conducted using both functional and discrete statistical analyses.Results:There were significant main effects for running speed and gradient on peak bending moments and peak anterior and posterior stress.Higher running speeds resulted in greater tibial loading.Running uphill at+10%and+15%resulted in greater tibial loading than level running.Running downhill at-10%and-15%resulted in reduced tibial loading compared to level running.There was no difference between+5%or-5%and level running.Conclusion:Running at faster speeds and uphill on gradients≥+10%increased internal tibial loading,whereas slower running and downhill running on gradients≥-10%reduced internal loading.Adapting running speed according to the gradient could be a protective mechanism,providing runners with a strategy to minimize the risk of tibial stress injuries. 展开更多
关键词 Bending moments GRADIENT Musculoskeletal modeling Overuse injury Tibial stress Training factors
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Synthesis of spherical nano-ZSM-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene
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作者 Siyue Wang Jinhong Li +5 位作者 Qingxin Xu Shengjie Song Yu'ni Jiang Lidong Chen Xin Shi Weiguo Cheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期298-309,共12页
Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to devel... Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous catalysts.Here,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce m-DEB.The results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore ZSM-5.And then,the spherical nano-ZSM-5 is further modified by La_(2)O_(3) through acid treatment followed by immersion method.The acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2)O_(3) loading reintroduces the weak acid sites.As a result,the HNO_(3)-La_(2)O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB selectivity.The catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with ethanol.The present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB. 展开更多
关键词 Zeolite Modification Alkylation reaction m-diethylbenzene Catalyst FIXED-BED
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Neuronal conversion from glia to replenish the lost neurons
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作者 Shiyu Liang Jing Zhou +2 位作者 Xiaolin Yu Shuai Lu Ruitian Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1446-1453,共8页
Neuronal injury,aging,and cerebrovascular and neurodegenerative diseases such as cerebral infarction,Alzheimer’s disease,Parkinson’s disease,frontotemporal dementia,amyotrophic lateral sclerosis,and Huntington’s di... Neuronal injury,aging,and cerebrovascular and neurodegenerative diseases such as cerebral infarction,Alzheimer’s disease,Parkinson’s disease,frontotemporal dementia,amyotrophic lateral sclerosis,and Huntington’s disease are characte rized by significant neuronal loss.Unfo rtunately,the neurons of most mammals including humans do not possess the ability to self-regenerate.Replenishment of lost neurons becomes an appealing therapeutic strategy to reve rse the disease phenotype.Transplantation of pluripotent neural stem cells can supplement the missing neurons in the brain,but it carries the risk of causing gene mutation,tumorigenesis,severe inflammation,and obstructive hydrocephalus induced by brain edema.Conversion of neural or non-neural lineage cells into functional neurons is a promising strategy for the diseases involving neuron loss,which may overcome the above-mentioned disadvantages of neural stem cell therapy.Thus far,many strategies to transfo rm astrocytes,fibroblasts,microglia,Muller glia,NG2 cells,and other glial cells to mature and functional neurons,or for the conversion between neuronal subtypes have been developed thro ugh the regulation of transcription factors,polypyrimidine tra ct binding protein 1(PTBP1),and small chemical molecules or are based on a combination of several factors and the location in the central nervous system.However,some recent papers did not obtain expected results,and discrepancies exist.Therefore,in this review,we discuss the history of neuronal transdifferentiation,summarize the strategies for neuronal replenishment and conversion from glia,especially astrocytes,and point out that biosafety,new strategies,and the accurate origin of the truly co nverted neurons in vivo should be focused upon in future studies.It also arises the attention of replenishing the lost neurons from glia by gene therapies such as up-regulation of some transc ription factors or downregulation of PTBP1 or drug interfe rence therapies. 展开更多
关键词 ASTROCYTES neural stem cells neurodegenerative diseases neuron polypyrimidine tract binding protein 1 repair REPROGRAMMING small molecule transcription factor TRANSDIFFERENTIATION
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Role of methoxy and C_(α)-based substituents in electrochemical oxidation mechanisms and bond cleavage selectivity of β-O-4 lignin model compounds
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作者 Yang Zhou Qiang Zeng +3 位作者 Hongyan He Kejia Wu Fuqiao Liu Xuehui Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期114-125,共12页
In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl gro... In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations. 展开更多
关键词 Lignin model compounds β-O-4 dimers Electrochemical oxidation Oxidation mechanisms Substituent effect
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Metagenomic analysis revealing the metabolic role of microbial communities in the free amino acid biosynthesis of Monascus rice vinegar during fermentation
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作者 Hang Gao Jian Zhang +4 位作者 Li Liu Lijun Fu Yan Zhao Germán Mazza Xin Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2317-2326,共10页
Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic netw... Free amino acid(FAA)is the important component of vinegar that infl uences quality perception and consumer acceptance.FAA is one of the major metabolites produced by microorganisms;however,the microbial metabolic network on FAA biosynthesis remains unclear.Through metagenomic analysis,this work aimed to elucidate the roles of microbes in FAA biosynthesis during Monascus rice vinegar fermentation.Taxonomic profiles from functional analyses showed 14 dominant genera with high contributions to the metabolism pathways.The metabolic network for FAA biosynthesis was then constructed,and the microbial distribution in different metabolic pathways was illuminated.The results revealed that 5 functional genera were closely involved in FAA biosynthesis.This study illuminated the metabolic roles of microorganisms in FAA biosynthesis and provided crucial insights into the functional attributes of microbiota in vinegar fermentation. 展开更多
关键词 Monascus rice vinegar Metagenomic analysis Free amino acid synthesis Metabolic pathway Microbial distribution
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Regulating the non-effective carriers transport for high-performance lithium metal batteries
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作者 Simeng Wang Youchun Yu +2 位作者 Shaotong Fu Hongtao Li Jiajia Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期132-141,共10页
The absence of control over carriers transport during electrochemical cycling,accompanied by the deterioration of the solid electrolyte interphase(SEI)and the growth of lithium dendrites,has hindered the development o... The absence of control over carriers transport during electrochemical cycling,accompanied by the deterioration of the solid electrolyte interphase(SEI)and the growth of lithium dendrites,has hindered the development of lithium metal batteries.Herein,a separator complexion consisting of polyacrylonitrile(PAN)nanofiber and MIL-101(Cr)particles prepared by electrospinning is proposed to bind the anions from the electrolyte utilizing abundant effective open metal sites in the MIL-101(Cr)particles to modulate the transport of non-effective carriers.The binding effect of the PANM separator promotes uniform lithium metal deposition and enhances the stability of the SEI layer and long cycling stability of ultra-high nickel layered oxide cathodes.Taking PANM as the Li||NCM96 separator enables high-voltage cycling stability,maintaining 72%capacity retention after 800 cycles at a charging and discharging rate of 0.2 C at a cut-off voltage of 4.5 V and 0°C.Meanwhile,the excellent high-rate performance delivers a specific capacity of 156.3 mA h g^(-1) at 10 C.In addition,outstanding cycling performance is realized from−20 to 60°C.The separator engineering facilitates the electrochemical performance of lithium metal batteries and enlightens a facile and promising strategy to develop fast charge/discharge over a wide range of temperatures. 展开更多
关键词 Functional separators Metal-organic frameworks 3D continuous ion transport networks ELECTROSPINNING Lithium metal batteries
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Long‐life lithium batteries enabled by a pseudo‐oversaturated electrolyte
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作者 Youchun Yu Simeng Wang +6 位作者 Juyan Zhang Weiwei Qian Nana Zhang Guangjie Shao Haiyan Bian Yuwen Liu Lan Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期115-127,共13页
The specific energy of Li metal batteries(LMBs)can be improved by using high‐voltage cathode materials;however,achieving long‐term stable cycling performance in the corresponding system is particularly challenging f... The specific energy of Li metal batteries(LMBs)can be improved by using high‐voltage cathode materials;however,achieving long‐term stable cycling performance in the corresponding system is particularly challenging for the liquid electrolyte.Herein,a novel pseudo‐oversaturated electrolyte(POSE)is prepared by introducing 1,1,2,2‐tetrafluoroethyl‐2,2,3,3‐tetrafluoropropyl ether(TTE)to adjust the coordination structure between diglyme(G2)and lithium bis(trifluoromethanesulfonyl)imide(LiTFSI).Surprisingly,although TTE shows little solubility to LiTFSI,the molar ratio between LiTFSI and G2 in the POSE can be increased to 1:1,which is much higher than that of the saturation state,1:2.8.Simulation and experimental results prove that TTE promotes closer contact of the G2 molecular with Li^(+)in the POSE.Moreover,it also participates in the formation of electrolyte/electrode interphases.The electrolyte shows outstanding compatibility with both the Li metal anode and typical high‐voltage cathodes.Li||Li symmetric cells show a long life of more than 2000 h at 1 mA cm^(−2),1 mAh cm^(−2).In the meantime,Li||LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cell with the POSE shows a high reversible capacity of 134.8 mAh g^(−1 )after 900 cycles at 4.5 V,1 C rate.The concept of POSE can provide new insight into the Li^(+)solvation structure and in the design of advanced electrolytes for LMBs. 展开更多
关键词 high voltage lithium metal batteries pseudo‐oversaturated electrolyte solid electrolyte interphases(SEI) solvation structure
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Grain refinement of Mg-Ca alloys by native MgO particles
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作者 Shihao Wang Yun Wang +1 位作者 Quentin M.Ramasse Zhongyun Fan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期980-996,共17页
In Mg-Ca alloys the grain refining mechanism,in particular regarding the role of nucleant substrates,remains the object of debates.Although native MgO is being recognised as a nucleating substrate accounting for grain... In Mg-Ca alloys the grain refining mechanism,in particular regarding the role of nucleant substrates,remains the object of debates.Although native MgO is being recognised as a nucleating substrate accounting for grain refinement of Mg alloys,the possible interactions of MgO with alloying elements that may alter the nucleation potency have not been elucidated yet.Herein,we design casting experiments of Mg-xCa alloys varied qualitatively in number density of native MgO,which are then comprehensively studied by advanced electron microscopy.The results show that grain refinement is enhanced as the particle number density of MgO increases.The native MgO particles are modified by interfacial layers due to the co-segregation of Ca and N solute atoms at the MgO/Mg interface.Using aberration-corrected scanning transmission electron microscopy and electron energy loss spectroscopy,we reveal the nature of these Ca/N interfacial layers at the atomic scale.Irrespective of the crystallographic termination of MgO,Ca and N co-segregate at the MgO/Mg interface and occupy Mg and O sites,respectively,forming an interfacial structure of a few atomic layers.The interfacial structure is slightly expanded,less ordered and defective compared to the MgO matrix due to compositional deviations,whereby the MgO substrate is altered as a poorer template to nucleate Mg solid.Upon solidification in a TP-1 mould,the impotent MgO particles account for the grain refining mechanism,where they are suggested to participate into nucleation and grain initiation processes in an explosive manner.This work not only reveals the atomic engineering of a substrate through interfacial segregation but also demonstrates the effectiveness of a strategy whereby native MgO particles can be harnessed for grain refinement in Mg-Ca alloys. 展开更多
关键词 Mg-Ca alloy Grain refinement MGO Interfacial segregation STEM/EELS Solidification.
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Integrated high-performance and accurate shaping technology of low-cost powder metallurgy titanium alloys: A comprehensive review
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作者 Xuemeng Gan Shaofu Li +1 位作者 Shunyuan Xiao Yafeng Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期413-426,共14页
The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O ... The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O impurities, and severe sintering deforma-tion resulting from the use of heterogeneous powder mixtures. This review presents a summary of our previous work on addressing the above challenges. Initially, we proposed a novel strategy using reaction-induced liquid phases to enhance sintering densification. Near- complete density (relative density exceeding 99%) was achieved by applying the above strategy and newly developed sintering aids. By focusing on the O-induced embrittlement issue, we determined the onset dissolution temperature of oxide films in the Ti matrix. On the basis of this finding, we established a design criterion for effective O scavengers that require reaction with oxide films before their dissol-ution. Consequently, a ductile PM Ti alloy was successfully obtained by introducing 0.3wt% NdB6 as the O scavenger. Lastly, a powder- coating strategy was adopted to address the sintering deformation issue. The ultrafine size and shell-like distribution characteristics of coating particles ensured rapid dissolution and homogeneity in the Ti matrix, thereby facilitating linear shrinkage during sintering. As a result, geometrically complex Ti alloy parts with high dimensional accuracy were fabricated by using the coated powder. Our fundament-al findings and related technical achievements enabled the development of an integrated production technology for the high-performance and accurate shaping of low-cost PM Ti alloys. Additionally, the primary engineering applications and progress in the industrialization practice of our developed technology are introduced in this review. 展开更多
关键词 powder metallurgy titanium sintering densification oxygen scavenging accurate shaping
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Filtration performance and modeling of granular bed for dust removal from coal pyrolytic vapors
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作者 Shuaiqiang Yang Lin Du +3 位作者 Guangchao Ding Runguo Liu Wenli Song Songgeng Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期35-42,共8页
Dust removal from pyrolytic vapors at high temperatures is an obstacle to the industrialization of the coal pyrolysis process.In this work,a granular bed with expanded perlites as filtration media was designed and int... Dust removal from pyrolytic vapors at high temperatures is an obstacle to the industrialization of the coal pyrolysis process.In this work,a granular bed with expanded perlites as filtration media was designed and integrated into a 10 t·d^(–1)coal pyrolysis facility.The testing results showed that around 97.56%dust collection efficiency was achieved.As a result,dust content in tar was significantly lowered.The pressure drop of the granular bed maintained in the range of 356 Pa to 489 Pa.The dust size in the effluent after filtration exhibited a bimodal distribution,which was attributed to the heterogeneity of the dust components.The effects of filtration bed on pyrolytic product yields were also discussed.A modified filtration model based on the macroscopic phenomenological theory was proposed to describe the performance of the granular bed.The computation results were well agreed with the experimental data. 展开更多
关键词 Granular bed filtration Dust removal PYROLYSIS FILTRATION FIXED-BED
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Porous metal oxides in the role of electrochemical CO_(2) reduction reaction
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作者 Ziqi Zhang Jinyun Xu +9 位作者 Yu Zhang Liping Zhao Ming Li Guoqiang Zhong Di Zhao Minjing Li Xudong Hu Wenju Zhu Chunming Zheng Xiaohong Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期373-398,I0009,共27页
The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous me... The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous metal oxide materials in the electrocatalytic reduction of CO_(2)(CO_(2)RR).The focus is on the development of robust and selective catalysts,particularly metal and metal-oxide-based materials.Porous metal oxides offer high surface area,enhancing the accessibility to active sites and improving reaction kinetics.The tunability of these materials allows for tailored catalytic behavior,targeting optimized reaction mechanisms for CO_(2)RR.The work also discusses the various synthesis strategies and identifies key structural and compositional features,addressing challenges like high overpotential,poor selectivity,and low stability.Based on these insights,we suggest avenues for future research on porous metal oxide materials for electrochemical CO_(2) reduction. 展开更多
关键词 CO_(2)reduction Carbon dioxide TRANSFORMATION Porous metal oxides ELECTROCATALYSIS
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