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In situ doping brushite on zinc manganese oxide toward enhanced water oxidation performance: Mimicry of an oxygen‐evolving complex
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作者 Miao Jiang Junying Chen Yingwei Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第6期1017-1026,共10页
We report in situ doping of brushite on zinc manganese oxide(ZMO), fabricated by calcining a Mn(II) oxalate‐impregnated metal‐organic framework. The doping process was conducted in com‐bination with the photoca... We report in situ doping of brushite on zinc manganese oxide(ZMO), fabricated by calcining a Mn(II) oxalate‐impregnated metal‐organic framework. The doping process was conducted in com‐bination with the photocatalytic water oxidation reaction which was catalyzed by ZMO in neutral phosphate‐buffered aqueous solution containing [Ru(bpy)3]^2+‐Na2S2O8 and calcium(II) triflate salt, exhibiting greatly enhanced water oxidation performance with optimized turnover frequency of 0.18 mmol(O2) mol(Mn)^(–1) s^(–1). Different analytical techniques indicated that photodeposited calci‐um‐phosphate(CaP) acted as a co‐catalyst to promote the O2 evolution activity of ZMO. This system involved the use of manganese oxide and calcium ion, and the operation was conducted under am‐bient temperature and neutral conditions, thus, it efficiently mimicked the oxygen‐evolving complex in photosystem II. 展开更多
关键词 Zincmanganese oxide Brushite Metal‐organic frameworks Water oxidation oxygen‐evolving COMPLEX
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Non‐catalytic,instant iridium(Ir)leaching:A non‐negligible aspect in identifying Ir‐based perovskite oxygen‐evolving electrocatalysts 被引量:1
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作者 Qi Zhang Hui Chen +6 位作者 Lan Yang Xiao Liang Lei Shi Qing Feng Yongcun Zou Guo‐Dong Li Xiaoxin Zou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第3期885-893,共9页
The large‐scale application of proton exchange membrane water electrolysis technology requires the development of high‐performance oxygen evolution electrocatalysts with as little iridium(Ir)as possible.Ir‐based do... The large‐scale application of proton exchange membrane water electrolysis technology requires the development of high‐performance oxygen evolution electrocatalysts with as little iridium(Ir)as possible.Ir‐based double perovskite oxides(A_(2)B’IrO_(6);A=alkaline,alkaline‐earth,or rare‐earth elements;B’=transition metal or rare‐earth elements)represent a class of oxides with great potential to replace the commercial catalyst IrO_(2).However,the structural evolution of Ir‐based double perovskite oxides in electrolytes is incompletely understood,and foundational knowledge of the design principle of the“ideal”material is lacking.In this work,we report the unexpected phenomenon of instant Ir leaching from Ir‐based double perovskite oxides in acid under non‐catalytic conditions and discuss the implications of this phenomenon for mechanism investigation and material identification.Some well‐known Ir‐based double perovskite oxides,such as Ba_(2)PrIrO_(6) and Sr_(2)YIrO_(6),undergo instantaneous Ir leaching when they come into contact with acidic electrolytes.The Ir‐leaching process is found to be non‐persistent and non‐thermodynamically determined,and its extent is correlated with the leaching of other B’‐site elements in the perovskite oxides.Based on this observation,we revisit the Ir dissolution‐precipitation process for surface IrO_(x) formation during the perovskite‐electrolyzed oxygen evolution reaction,emphasizing the non‐negligible role of Ir species owing to acid corrosion in the electrolyte.Finally,we modify a screening protocol for low‐Ir oxygen evolution electrocatalysts and propose an instant acid corrosion test as an indispensable process to evaluate the structural stability of potential catalysts. 展开更多
关键词 oxygen evolution reaction Water splitting IRIDIUM Stability PEROVSKITE
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Tuning synergy between nickel and iron in Ruddlesden-Popper perovskites through controllable crystal dimensionalities towards enhanced oxygenevolving activity and stability
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作者 Haijuan Zhang Daqin Guan +4 位作者 Yuxing Gu Hengyue Xu Chunchang Wang Zongping Shao Youmin Guo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期113-123,共11页
Ni-Fe-based oxides are among the most promising catalysts developed to date for the bottleneck oxygen evolution reaction(OER)in water electrolysis.However,understanding and mastering the synergy of Ni and Fe remain ch... Ni-Fe-based oxides are among the most promising catalysts developed to date for the bottleneck oxygen evolution reaction(OER)in water electrolysis.However,understanding and mastering the synergy of Ni and Fe remain challenging.Herein,we report that the synergy between Ni and Fe can be tailored by crystal dimensionality of Ni,Fe-contained Ruddlesden-Popper(RP)-type perovskites(La_(0.125)Sr_(0.875))n+1(Ni_(0.25)Fe_(0.75))nO3n+1(n=1,2,3),where the material with n=3 shows the best OER performance in alkaline media.Soft X-ray absorption spectroscopy spectra before and after OER reveal that the material with n=3 shows enhanced Ni/Fe-O covalency to boost the electron transfer as compared to those with n=1 and n=2.Further experimental investigations demonstrate that the Fe ion is the active site and the Ni ion is the stable site in this system,where such unique synergy reaches the optimum at n=3.Besides,as n increases,the proportion of unstable rock-salt layers accordingly decreases and the leaching of ions(especially Sr^(2+))into the electrolyte is suppressed,which induces a decrease in the leaching of active Fe ions,ultimately leading to enhanced stability.This work provides a new avenue for rational catalyst design through the dimensional strategy. 展开更多
关键词 crystal dimensionalities oxygen evolution reaction Ruddlesden-Popper perovskites SYNERGY
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英国高中地理教材栏目设置的特点及启示——以Geography B Evolving Planet为例
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作者 徐波 安龙 +3 位作者 袁圆 欧然然 谢庆玲 冯婷 《咸阳师范学院学报》 2023年第4期84-88,共5页
以英国中学地理教材Geography B Evolving Planet中的教材栏目为研究对象,结合其在教材中实际发挥的功能,将八种主要的教材栏目划分为问题思考类、技能训练类、信息提示类和考试导向类四大类。这四大类教材栏目体现出了不同的特点。问... 以英国中学地理教材Geography B Evolving Planet中的教材栏目为研究对象,结合其在教材中实际发挥的功能,将八种主要的教材栏目划分为问题思考类、技能训练类、信息提示类和考试导向类四大类。这四大类教材栏目体现出了不同的特点。问题思考类栏目指向不同教学目标,技能训练类栏目凸显实用性和应用性的学科特色,信息提示类栏目关注学生心理特点,考试导向类栏目提高应试答题技巧。受此启发,未来我国中学地理教材栏目设置应有所侧重,即教材栏目在内容设置上要注重针对性,在形式设置上要增加多样性,在外观设置上要注重醒目性。 展开更多
关键词 地理教材 Geography B evolving Planet 教材栏目
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Purification and Spectral Characteristics of Cytochrome b-559 from Oxygen-evolving Photosystem Ⅱ Core Complexes of Spinach and Rice
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作者 辛越勇 郁飞 +2 位作者 唐崇钦 李良璧 匡廷云 《Acta Botanica Sinica》 CSCD 2000年第12期1225-1230,共6页
Cytochrome b_559 in photosystem Ⅱ reaction center was purified from spinach ( Spinacia oleracea L.) and rice ( Oryza sativa L.) by a rapid and simple procedure. Their low temperature fluorescence emission and e... Cytochrome b_559 in photosystem Ⅱ reaction center was purified from spinach ( Spinacia oleracea L.) and rice ( Oryza sativa L.) by a rapid and simple procedure. Their low temperature fluorescence emission and excitation spectra, ultraviolet fluorescence spectra and absolute absorption spectra were presented. The author's purification methods, which enhanced the yield of pure protein and shorted the time for isolation, have several advantages: 1. use of oxygen_evolving PSⅡ core complexes as the starting material in order to avoid disturbing from other cytochromes; 2. isocratic elution of cytochrome b_559 from a DEAE_Sephacel column for eliminating the impurity and yielding the protein in pure state; 3. a simple column procedure for removal of excess Triton X_100. Purified cytochromes b_559 from these species have similar optical spectra and mobility during gel electrophoresis under native conditions. From the results of novel electrophoresis (Tricine_SDS_PAGE), cytochrome b_559 from both spinach and rice reveal two polypeptide bands (apparent molecular weight 9 kD and 4 kD, respectively). By measuring of 77 K fluorescence spectra, it was shown that for the purified cytochrome b_559 there were two excitation peaks at 439 nm and 413 nm, and two emission peaks at 563 nm and 668 nm. This is the first indication that Cyt b_559 is able to emit fluorescence and also transfer excited electrons to chlorophyll. By the use of ultraviolet fluorescence spectra, it was demonstrated for the first time that the location of Trp residue could be in the hydrophobic transmembrane region of cytochrome b_559. 展开更多
关键词 cytochrome b_559 oxygen evolution PSⅡ core complexes Tricine_SDS_PAGE optical spectra
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Immobilization of Oxyanions on the Reconstructed Heterostructure Evolved from a Bimetallic Oxysulfide for the Promotion of Oxygen Evolution Reaction 被引量:1
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作者 Kai Yu Hongyuan Yang +6 位作者 Hao Zhang Hui Huang Zhaowu Wang Zhenhui Kang Yang Liu Prashanth W.Menezes Ziliang Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期547-564,共18页
Efficient and durable oxygen evolution reaction(OER)requires the electrocatalyst to bear abundant active sites,optimized electronic structure as well as robust component and mechanical stability.Herein,a bimetallic la... Efficient and durable oxygen evolution reaction(OER)requires the electrocatalyst to bear abundant active sites,optimized electronic structure as well as robust component and mechanical stability.Herein,a bimetallic lanthanum-nickel oxysulfide with rich oxygen vacancies based on the La_(2)O_(2)S prototype is fabricated as a binder-free precatalyst for alkaline OER.The combination of advanced in situ and ex situ characterizations with theoretical calculation uncovers the synergistic effect among La,Ni,O,and S species during OER,which assures the adsorption and stabilization of the oxyanion SO_(4)^(2-)onto the surface of the deeply reconstructed porous heterostructure composed of confining Ni OOH nanodomains by La(OH)_3 barrier.Such coupling,confinement,porosity and immobilization enable notable improvement in active site accessibility,phase stability,mass diffusion capability and the intrinsic Gibbs free energy of oxygen-containing intermediates.The optimized electrocatalyst delivers exceptional alkaline OER activity and durability,outperforming most of the Ni-based benchmark OER electrocatalysts. 展开更多
关键词 Lanthanum-nickel oxysulfide Rare earth metal Immobilization of oxyanions Structural reconstruction oxygen evolution catalysis
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Strong synergy between physical and chemical properties:Insight into optimization of atomically dispersed oxygen reduction catalysts 被引量:4
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作者 Yifan Zhang Linsheng Liu +4 位作者 Yuxuan Li Xueqin Mu Shichun Mu Suli Liu Zhihui Dai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期36-49,共14页
Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utiliz... Atomically dispersed catalysts exhibit significant influence on facilitating the sluggish oxygen reduction reaction(ORR)kinetics with high atom economy,owing to remarkable attributes including nearly 100%atomic utilization and exceptional catalytic functionality.Furthermore,accurately controlling atomic physical properties including spin,charge,orbital,and lattice degrees of atomically dispersed catalysts can realize the optimized chemical properties including maximum atom utilization efficiency,homogenous active centers,and satisfactory catalytic performance,but remains elusive.Here,through physical and chemical insight,we review and systematically summarize the strategies to optimize atomically dispersed ORR catalysts including adjusting the atomic coordination environment,adjacent electronic orbital and site density,and the choice of dual-atom sites.Then the emphasis is on the fundamental understanding of the correlation between the physical property and the catalytic behavior for atomically dispersed catalysts.Finally,an overview of the existing challenges and prospects to illustrate the current obstacles and potential opportunities for the advancement of atomically dispersed catalysts in the realm of electrocatalytic reactions is offered. 展开更多
关键词 Atomically dispersed catalysts Coordination environment Electronic orbitals Inter-site distance effect oxygen reduction reaction
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A defective iron-based perovskite cathode for high-performance IT-SOFCs:Tailoring the oxygen vacancies using Nb/Ta co-doping 被引量:2
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作者 Bayu Admasu Beshiwork Xinyu Wan +6 位作者 Min Xu Haoran Guo Birkneh Sirak Teketel Yu Chen Jun Song Chen Tingshuai Li Enrico Traversa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期306-316,I0008,共12页
The sluggish kinetics of the electrochemical oxygen reduction reaction(ORR)in intermediatetemperature solid oxide fuel cells(IT-SOFCs)greatly limits the overall cell performance.In this study,an efficient and durable ... The sluggish kinetics of the electrochemical oxygen reduction reaction(ORR)in intermediatetemperature solid oxide fuel cells(IT-SOFCs)greatly limits the overall cell performance.In this study,an efficient and durable cathode material for IT-SOFCs is designed based on density functional theory(DFT)calculations by co-doping with Nb and Ta the B-site of the SrFeO_(3-δ)perovskite oxide.The DFT calculations suggest that Nb/Ta co-doping can regulate the energy band of the parent SrFeO_(3-δ)and help electron transfer.In symmetrical cells,such cathode with a SrFe_(0.8)Nb_(0.1)Ta_(0.1)O_(3-δ)(SFNT)detailed formula achieves a low cathode polarization resistance of 0.147Ωcm^(2) at 650℃.Electron spin resonance(ESR)and X-ray photoelectron spectroscopy(XPS)analysis confirm that the co-doping of Nb/Ta in SrFeO_(3-δ)B-site increases the balanced concentration of oxygen vacancies,enhancing the electrochemical performance when compared to 20 mol%Nb single-doped perovskite oxide.The cathode button cell with NiSDC|SDC|SFNT configuration achieves an outstanding peak power density of 1.3 W cm^(-2)at 650℃.Moreover,the button cell shows durability for 110 h under 0.65 V at 600℃ using wet H_(2) as fuel. 展开更多
关键词 Solid oxide fuel cell CATHODE oxygen reduction reaction Power density DFT calculation
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Valence electronic engineering of superhydrophilic Dy-evoked Ni-MOF outperforming RuO_(2) for highly efficient electrocatalytic oxygen evolution 被引量:1
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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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Microwave shock motivating the Sr substitution of 2D porous GdFeO_(3) perovskite for highly active oxygen evolution 被引量:1
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作者 Jinglin Xian Huiyu Jiang +10 位作者 Zhiao Wu Huimin Yu Kaisi Liu Miao Fan Rong Hu Guangyu Fang Liyun Wei Jingyan Cai Weilin Xu Huanyu Jin Jun Wan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期232-241,I0006,共11页
The incorporation of partial A-site substitution in perovskite oxides represents a promising strategy for precisely controlling the electronic configuration and enhancing its intrinsic catalytic activity.Conventional ... The incorporation of partial A-site substitution in perovskite oxides represents a promising strategy for precisely controlling the electronic configuration and enhancing its intrinsic catalytic activity.Conventional methods for A-site substitution typically involve prolonged high-temperature processes.While these processes promote the development of unique nanostructures with highly exposed active sites,they often result in the uncontrolled configuration of introduced elements.Herein,we present a novel approach for synthesizing two-dimensional(2D)porous GdFeO_(3) perovskite with A-site strontium(Sr)substitution utilizing microwave shock method.This technique enables precise control of the Sr content and simultaneous construction of 2D porous structures in one step,capitalizing on the advantages of rapid heating and cooling(temperature~1100 K,rate~70 K s^(-1)).The active sites of this oxygen-rich defect structure can be clearly revealed through the simulation of the electronic configuration and the comprehensive analysis of the crystal structure.For electrocatalytic oxygen evolution reaction application,the synthesized 2D porous Gd_(0.8)Sr_(0.2)FeO_(3) electrocatalyst exhibits an exceptional overpotential of 294 mV at a current density of 10 mA cm^(-2)and a small Tafel slope of 55.85 mV dec^(-1)in alkaline electrolytes.This study offers a fresh perspective on designing crystal configurations and the construction of nanostructures in perovskite. 展开更多
关键词 2D materials PEROVSKITE MICROWAVE ELECTROCATALYSIS oxygen evolution reaction
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Tuning electronic structure of RuO_(2)by single atom Zn and oxygen vacancies to boost oxygen evolution reaction in acidic medium 被引量:1
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作者 Qing Qin Tiantian Wang +7 位作者 Zijian Li Guolin Zhang Haeseong Jang Liqiang Hou Yu Wang Min Gyu Kim Shangguo Liu Xien Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期94-102,I0003,共10页
The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct ... The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct activity-stability trade-off model is full of significance but challenging.Herein,a single atom Zn stabilized RuO_(2)with enriched oxygen vacancies(SA Zn-RuO_(2))is developed as a promising alternative to iridium oxide for acidic oxygen evolution reaction(OER).Compared with commercial RuO_(2),the enhanced Ru–O bond strength of SA Zn-RuO_(2)by forming Zn-O-Ru local structure motif is favorable to stabilize surface Ru,while the electrons transferred from Zn single atoms to adjacent Ru atoms protects the Ru active sites from overoxidation.Simultaneously,the optimized surrounding electronic structure of Ru sites in SA ZnRuO_(2)decreases the adsorption energies of OER intermediates to reduce the reaction barrier.As a result,the representative SA Zn-RuO_(2)exhibits a low overpotential of 210 mV to achieve 10 mA cm^(-2)and a greatly enhanced durability than commercial RuO_(2).This work provides a promising dual-engineering strategy by coupling single atom doping and vacancy for the tradeoff of high activity and catalytic stability toward acidic OER. 展开更多
关键词 ELECTROCATALYST Acidic oxygen evolution reaction Electronic structure engineering DURABILITY Reaction barrier
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Highly sensitive ratiometric fluorescent fiber matrices for oxygen sensing with micrometer spatial resolution 被引量:1
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作者 Giuliana Grasso Valentina Onesto +8 位作者 Stefania Forciniti Eliana D’Amone Francesco Colella Lara Pierantoni Valeria Famà Giuseppe Gigli Rui L.Reis J.Miguel Oliveira Loretta L.del Mercato 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第3期292-306,共15页
Oxygen(O_(2))-sensing matrices are promising tools for the live monitoring of extracellular O_(2) consumption levels in long-term cell cultures.In this study,ratiometric O_(2)-sensing membranes were prepared by electr... Oxygen(O_(2))-sensing matrices are promising tools for the live monitoring of extracellular O_(2) consumption levels in long-term cell cultures.In this study,ratiometric O_(2)-sensing membranes were prepared by electrospinning,an easy,low-cost,scalable,and robust method for fabricating nanofibers.Poly(ε-caprolactone)and poly(dimethyl)siloxane polymers were blended with tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)dichloride,which was used as the O_(2)-sensing probe,and rhodamine B isothiocyanate,which was used as the reference dye.The functionalized scaffolds were morphologically characterized by scanning electron microscopy,and their physicochemical profiles were obtained by Fourier transform infrared spectroscopy,thermogravimetric analysis,and water contact angle measurement.The sensing capabilities were investigated by confocal laser scanning microscopy,performing photobleaching,reversibility,and calibration curve studies toward different dissolved O_(2)(DO)concentrations.Electrospun sensing nanofibers showed a high response to changes in DO concentrations in the physiological-pathological range from 0.5%to 20%and good stability under ratiometric imaging.In addition,the sensing systems were highly biocompatible for cell growth promoting adhesiveness and growth of three cancer cell lines,namely metastatic melanoma cell line SK-MEL2,breast cancer cell line MCF-7,and pancreatic ductal adenocarcinoma cell line Panc-1,thus recreating a suitable biological environment in vitro.These O_(2)-sensing biomaterials can potentially measure alterations in cell metabolism caused by changes in ambient O_(2)content during drug testing/validation and tissue regeneration processes. 展开更多
关键词 ELECTROSPINNING Ruthenium(II)dichloride oxygen sensors Ratiometric imaging Fluorescence
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Single-atom catalysts for the electrochemical reduction of carbon dioxide into hydrocarbons and oxygenates 被引量:1
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作者 Karl Adrian Gandionco Juwon Kim +2 位作者 Lieven Bekaert Annick Hubin Jongwoo Lim 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期64-117,共54页
The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic ... The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic material and renewable energy-generated electricity drive the conversion of carbon dioxide into high-value chemicals and carbon-neutral fuels.Over the past few years,single-atom catalysts have been intensively studied as they could provide near-unity atom utilization and unique catalytic performance.Single-atom catalysts have become one of the state-of-the-art catalyst materials for the electrochemical reduction of carbon dioxide into carbon monoxide.However,it remains a challenge for single-atom catalysts to facilitate the efficient conversion of carbon dioxide into products beyond carbon monoxide.In this review,we summarize and present important findings and critical insights from studies on the electrochemical carbon dioxide reduction reaction into hydrocarbons and oxygenates using single-atom catalysts.It is hoped that this review gives a thorough recapitulation and analysis of the science behind the catalysis of carbon dioxide into more reduced products through singleatom catalysts so that it can be a guide for future research and development on catalysts with industry-ready performance for the electrochemical reduction of carbon dioxide into high-value chemicals and carbon-neutral fuels. 展开更多
关键词 ELECTROCATALYSIS electrochemical CO_(2)reduction hydrocarbons oxygenATES single-atom catalysts
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Paradoxical herniation associated with hyperbaric oxygen therapy after decompressive craniectomy: A case report 被引量:1
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作者 Zhong-Xing Ye Xin-Xin Fu +6 位作者 Yang-Zong Wu Ling Lin Liang-Qi Xie Yu-Ling Hu Yi Zhou Zhu-Gui You Hai Lin 《World Journal of Clinical Cases》 SCIE 2024年第10期1793-1798,共6页
BACKGROUND Whether hyperbaric oxygen therapy(HBOT)can cause paradoxical herniation is still unclear.CASE SUMMARY A 65-year-old patient who was comatose due to brain trauma underwent decompressive craniotomy and gradua... BACKGROUND Whether hyperbaric oxygen therapy(HBOT)can cause paradoxical herniation is still unclear.CASE SUMMARY A 65-year-old patient who was comatose due to brain trauma underwent decompressive craniotomy and gradually regained consciousness after surgery.HBOT was administered 22 d after surgery due to speech impairment.Paradoxical herniation appeared on the second day after treatment,and the patient’s condition worsened after receiving mannitol treatment at the rehabilitation hospital.After timely skull repair,the paradoxical herniation was resolved,and the patient regained consciousness and had a good recovery as observed at the follow-up visit.CONCLUSION Paradoxical herniation is rare and may be caused by HBOT.However,the underlying mechanism is unknown,and the understanding of this phenomenon is insufficient.The use of mannitol may worsen this condition.Timely skull repair can treat paradoxical herniation and prevent serious complications. 展开更多
关键词 Decompressive craniectomy Hyperbaric oxygen therapy MANNITOL Paradoxical herniation Case report
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An Overview of Government-Market Relationships:Evolving Perceptions,Role of the Market,and Government Functions
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作者 Li Xiang Tang Yong 《Contemporary Social Sciences》 2023年第3期65-84,共20页
Building a high-level socialist market economy is conducive to giving full play to the market’s decisive role in resource allocations and bringing the government into better play.Correctly handling the market and the... Building a high-level socialist market economy is conducive to giving full play to the market’s decisive role in resource allocations and bringing the government into better play.Correctly handling the market and the government relationships has been a central issue in China’s economic structural reform.Giving a comprehensive review and summary of the research findings achieved by the theoretical and academic circles in China,we generalize the evolution and working mechanisms of China’s socialist market economy system,following the developing trajectory and logic of relevant literature,focusing on the three aspects of evolving perceptions,the role of the market,and the functions of the government.Based on our literature overview,we also induced and extracted the basic conclusions and evolutionary features of relevant research and made suggestions for the future direction of theoretical research regarding China’s socialist market economy. 展开更多
关键词 socialist market economy system evolving perceptions the role of the market government functions
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The Evolving Bipartite Network and Semi-Bipartite Network Models with Adjustable Scale and Hybrid Attachment Mechanisms
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作者 Peng Zuo Zhen Jia 《Open Journal of Applied Sciences》 2023年第10期1689-1703,共15页
The bipartite graph structure exists in the connections of many objects in the real world, and the evolving modeling is a good method to describe and understand the generation and evolution within various real complex... The bipartite graph structure exists in the connections of many objects in the real world, and the evolving modeling is a good method to describe and understand the generation and evolution within various real complex networks. Previous bipartite models were proposed to mostly explain the principle of attachments, and ignored the diverse growth speed of nodes of sets in different bipartite networks. In this paper, we propose an evolving bipartite network model with adjustable node scale and hybrid attachment mechanisms, which uses different probability parameters to control the scale of two disjoint sets of nodes and the preference strength of hybrid attachment respectively. The results show that the degree distribution of single set in the proposed model follows a shifted power-law distribution when parameter r and s are not equal to 0, or exponential distribution when r or s is equal to 0. Furthermore, we extend the previous model to a semi-bipartite network model, which embeds more user association information into the internal network, so that the model is capable of carrying and revealing more deep information of each user in the network. The simulation results of two models are in good agreement with the empirical data, which verifies that the models have a good performance on real networks from the perspective of degree distribution. We believe these two models are valuable for an explanation of the origin and growth of bipartite systems that truly exist. 展开更多
关键词 Bipartite Networks evolving Model Semi-Bipartite Networks Hybrid Attachment Degree Distribution
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Hybrid model for BOF oxygen blowing time prediction based on oxygen balance mechanism and deep neural network
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作者 Xin Shao Qing Liu +3 位作者 Zicheng Xin Jiangshan Zhang Tao Zhou Shaoshuai Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期106-117,共12页
The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based ... The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter. 展开更多
关键词 basic oxygen furnace oxygen consumption oxygen blowing time oxygen balance mechanism deep neural network hybrid model
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Unveiling the chemistry behind the electrolytic production of hydrogen peroxide by oxygenated carbon
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作者 Pan Xiang Kunshang Yang +6 位作者 Qihao Yang Yang Gao Wenwen Xu Zhiyi Lu Liang Chen Zhiming Wang Ziqi Tian 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期49-58,共10页
Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction reaction.The nature of the active functional group and u... Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction reaction.The nature of the active functional group and underlying reaction mechanism,however,remain unclear.Here,a comprehensive workflow was established to identify the active sites from the numerous possible structures.The common hydroxyl group at the notched edge demonstrates a key role in the two-electron process.The local chemical environment weakens the binding of OOH intermediate to substrate while enhancing interaction with solution,thereby promoting the H_(2)O_(2)production.With increasing pH,the intramolecular hydrogen bond between OOH intermediate and hydroxyl decreases,facilitating OOH desorption.Furthermore,the rise in selectivity with increasing potential stems from the suppression of the four-electron process.The active site was further validated through experiments.Guided by theoretical understanding,optimal performance was achieved with high selectivity(>95%)and current density(2.06 mA/cm^(2))in experiment. 展开更多
关键词 First-principles calculation oxygen reductionreaction Hydrogen peroxide production Fixed-potential method oxygenated carbon materials
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Reversed charge transfer induced by nickel in Fe-Ni/Mo_(2)C@nitrogen-doped carbon nanobox for promoted reversible oxygen electrocatalysis
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作者 Zhicheng Nie Lei Zhang +4 位作者 Qiliang Zhu Zhifan Ke Yingtang Zhou Thomas Wågberg Guangzhi Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期202-212,I0005,共12页
The interaction between metal and support is critical in oxygen catalysis as it governs the charge transfer between these two entities,influences the electronic structures of the supported metal,affects the adsorption... The interaction between metal and support is critical in oxygen catalysis as it governs the charge transfer between these two entities,influences the electronic structures of the supported metal,affects the adsorption energies of reaction intermediates,and ultimately impacts the catalytic performance.In this study,we discovered a unique charge transfer reversal phenomenon in a metal/carbon nanohybrid system.Specifically,electrons were transferred from the metal-based species to N-doped carbon,while the carbon support reciprocally donated electrons to the metal domain upon the introduction of nickel.This led to the exceptional electrocatalytic performances of the resulting Ni-Fe/Mo_(2)C@nitrogen-doped carbon catalyst,with a half-wave potential of 0.91 V towards oxygen reduction reaction(ORR)and a low overpotential of 290 m V at 10 mA cm^(-2)towards oxygen evolution reaction(OER)under alkaline conditions.Additionally,the Fe-Ni/Mo_(2)C@carbon heterojunction catalyst demonstrated high specific capacity(794 mA h g_(Zn)~(-1))and excellent cycling stability(200 h)in a Zn-air battery.Theoretical calculations revealed that Mo_(2)C effectively inhibited charge transfer from Fe to the support,while secondary doping of Ni induced a charge transfer reversal,resulting in electron accumulation in the Fe-Ni alloy region.This local electronic structure modulation significantly reduced energy barriers in the oxygen catalysis process,enhancing the catalytic efficiency of both ORR and OER.Consequently,our findings underscore the potential of manipulating charge transfer reversal between the metal and support as a promising strategy for developing highly-active and durable bi-functional oxygen electrodes. 展开更多
关键词 Metal-support interaction Charge transfer reversal oxygen reduction reaction oxygen evolution reaction Zinc-air battery
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Suppress oxygen evolution of lithium-rich manganese-based cathode materials via an integrated strategy
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作者 Wenhua Yu Yanyan Wang +5 位作者 Aimin Wu Aikui Li Zhiwen Qiu Xufeng Dong Chuang Dong Hao Huang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期138-151,共14页
Improving the reversibility of anionic redox and inhibiting irreversible oxygen evolution are the main challenges in the application of high reversible capacity Li-rich Mn-based cathode materials.A facile synchronous ... Improving the reversibility of anionic redox and inhibiting irreversible oxygen evolution are the main challenges in the application of high reversible capacity Li-rich Mn-based cathode materials.A facile synchronous lithiation strategy combining the advantages of yttrium doping and LiYO_(2) surface coating is proposed.Yttrium doping effectively suppresses the oxygen evolution during the delithiation process by increasing the energy barrier of oxygen evolution reaction through strong Y–O bond energy.LiYO_(2) nanocoating has the function of structural constraint and protection,that protecting the lattice oxygen exposed to the surface,thus avoiding irreversible oxidation.As an Li^(+) conductor,LiYO_(2) nano-coating can provide a fast Li^(+) transfer channel,which enables the sample to have excellent rate performance.The synergistic effect of Y doping and nano-LiYO_(2) coating integration suppresses the oxygen release from the surface,accelerates the diffusion of Li^(+)from electrolyte to electrode and decreases the interfacial side reactions,enabling the lithium ion batteries to obtain good electrochemical performance.The lithium-ion full cell employing the Y-1 sample(cathode)and commercial graphite(anode)exhibit an excellent specific energy density of 442.9 Wh kg^(-1) at a current density of 0.1C,with very stable safety performance,which can be used in a wide temperature range(60 to-15℃)stable operation.This result illustrates a new integration strategy for advanced cathode materials to achieve high specific energy density. 展开更多
关键词 Lithium-rich manganese-based cathodes Lithium ion batteries oxygen redox oxygen evolution Integrated strategy
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