期刊文献+
共找到9,605篇文章
< 1 2 250 >
每页显示 20 50 100
Cultural competence, secularism,agnostic/theistic evolution, ad hominem attacks, cherry-picking and constructivism:Best pedagogy or politics in evolutionary education research?
1
作者 Özgür Taskın 《Cultures of Science》 2025年第1期24-37,共14页
This paper is about the transformation process of theoretical frameworks used in educational research on teaching evolution. To this end, some authors' claims, findings and suggestions offered via particular studi... This paper is about the transformation process of theoretical frameworks used in educational research on teaching evolution. To this end, some authors' claims, findings and suggestions offered via particular studies are evaluated. While the evaluated authors have represented secularism as a barrier to teaching evolution in the United States, they have also offered pedagogically theistic or agnostic evolution as the best choice for the reconciliation of religion and evolution. This paper is particularly concerned with one of the explanatory theoretical frameworks—religious cultural competence in evolution education(ReCCEE), which is derived from the cultural competence framework—although others are visited as well. Even though the schools or authors who have applied ReCCEE do not directly reference constructivism, their studies are built upon constructivist pedagogy and epistemological idealism. They often have problematic issues such as obscurantism, ad hominem attacks, cherry-picking and an ill-formed appeal to authority. Besides, these papers present biased or uncritical views and ill-informed definitions of some terms, such as secularism and agnosticism. 展开更多
关键词 Theory of evolution CONSTRUCTIVISM cultural competence SECULARISM agnostic evolution obscurantism
在线阅读 下载PDF
Covalent organic framework assisted low-content ultrafine Ru on porous N-doped carbon for efficient hydrogen evolution reaction
2
作者 Kong-Gang Qu Zhi-Fei Chen +6 位作者 Li-Hui Wang Hai-Bo Li Su-Yuan Zeng Rui Li Li-Jian Meng Hong-Yan Chen Qing-Xia Yao 《Rare Metals》 2025年第3期2094-2102,共9页
Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru ... Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance. 展开更多
关键词 porous n doped carbon most superior cost performance hydrogen evolution reaction water splittingthe cost performance cathodic hydrogen evolution reaction her covalent organic framework ultrafine Ru
原文传递
Iridium-based electrocatalysts for acidic oxygen evolution reaction
3
作者 Yanhui Yu Gai Li +10 位作者 Yutong Xiao Chi Chen Yuhang Bai Tianjiao Wang Jing Li Yingjie Hua Daoxiong Wu Peng Rao Peilin Deng Xinlong Tian Yuliang Yuan 《Journal of Energy Chemistry》 2025年第4期200-224,共25页
Hydrogen production from water electrolysis,in particular from proton exchange membrane water electrolyzers(PEMWE),is a key approach to realizing a carbon-free energy cycle.However,the high anodic potential and strong... Hydrogen production from water electrolysis,in particular from proton exchange membrane water electrolyzers(PEMWE),is a key approach to realizing a carbon-free energy cycle.However,the high anodic potential and strong acid in PEMWE systems pose a major challenge to the stability of electrocatalysts,and the development of efficient and corrosion-resistant catalysts is urgently needed.Currently,iridium(Ir)-based catalysts have gained great attention due to their promising activity and stability,while the extremely low reserves of Ir in the earth seriously hinder the commercialization of PEMWE.Therefore,a systematic understanding of the latest advances in Ir-based catalysts is necessary to guide their rational design to meet the industrial requirements.In this review,the general reaction mechanisms and advanced characterization techniques for mechanism recognition are first introduced.Afterwards,the systematic design strategies and performances of Ir-based catalysts,including metallic Ir,Ir oxides,and Ir-based perovskites,are summarized in detail.Finally,the conclusions,challenges,and prospects for Ir-based electrocatalysts are presented. 展开更多
关键词 ELECTROLYSIS Water splitting Oxygen evolution reaction Ir-based catalysts Oxygen evolution reaction mechanisms
在线阅读 下载PDF
Unveiling complexities:Reviews on insights into the mechanism of oxygen evolution reaction
4
作者 Pengxiang Zhang Jiawen Wang +7 位作者 Tianyu Yang Ruizhe Wang Ruofan Shen Zhikun Peng Yanyan Liu Xianli Wu Jianchun Jiang Baojun Li 《Chinese Journal of Catalysis》 2025年第5期48-83,共36页
The study of the oxygen evolution reaction(OER)mechanism is vital for advancing our understanding of this pivotal energy conversion process.This review synthesizes recent advancements in OER mechanism,emphasizing the ... The study of the oxygen evolution reaction(OER)mechanism is vital for advancing our understanding of this pivotal energy conversion process.This review synthesizes recent advancements in OER mechanism,emphasizing the intricate relationship between catalytic mechanisms and catalyst design.This review discusses the connotation and cutting-edge progress of traditional mechanisms such as adsorbate evolution mechanism(AEM)and lattice oxygen mechanism(LOM)as well as emerging pathways including oxide path mechanism(OPM),oxo-oxo coupling mechanism(OCM),and intramolecular oxygen coupling mechanism(IMOC)etc.Innovative research progress on the coexistence and transformation of multiple mechanisms is highlighted,and the intrinsic factors that influence these dynamic processes are summarized.Advanced characterization techniques and theoretical modeling are underscored as indispensable tools for revealing these complex interactions.This review provides guiding principles for mechanism-based catalyst design.Finally,in view of the multidimensional challenges currently faced by OER mechanisms,prospects for future research are given to bridge the gap between mechanism innovation and experimental verification and application.This comprehensive review provides valuable perspectives for advancing clean energy technologies and achieving sustainable development. 展开更多
关键词 Oxygen evolution reaction Catalytic mechanism Catalyst design Adsorption evolution mechanism Lattice oxygen mechanism
在线阅读 下载PDF
Regulating Reconstruction-Engineered Active Sites of CoP Electrocatalyst by Br Ions During the Oxygen and Hydrogen Evolution Reaction
5
作者 Jing Yao Yuanyuan Zhang +6 位作者 Feng Gao Qi Jin Lirong Zhang Lingling Xu Mingyi Zhang Hong Gao Peng Yu 《Energy & Environmental Materials》 2025年第4期198-206,共9页
An in-depth understanding of the catalyst surface evolution is crucial for precise control of active sites,yet this aspect has often been overlooked.This study reveals the spontaneous anion regulation mechanism of Br-... An in-depth understanding of the catalyst surface evolution is crucial for precise control of active sites,yet this aspect has often been overlooked.This study reveals the spontaneous anion regulation mechanism of Br-doped CoP electrocatalysts in the alkaline hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).The introduction of Br modulates the electronic structure of the Co site,endowing Br-CoP with a more metallic character.In addition,P ion leaching promotes the in situ reconstruction of Br-CoOOH,which is the real active site for the OER reaction.Meanwhile,the HER situation is different.On the basis of P ion leaching,the leaching of Br ions promotes the formation of CoP-Co(OH)_(2) active species.In addition,Br doping enhances the adsorption of^(*)H,showing excellent H adsorption free energy,thereby greatly improving the HER activity.Simultaneously,it also enhances the adsorption of OOH^(*),effectively facilitating the occurrence of OER reactions.Br-CoP only needs 261 and 76 mV overpotential to drive the current density of 20 mA cm^(-2) and 10 mA^(-2),which can be maintained unchanged for 100 h.This study provides new insights into anion doping strategies and catalyst reconstruction mechanisms. 展开更多
关键词 anion exchange mechanism Br-CoP hydrogen evolution reaction oxygen evolution reaction surface reconstruction
在线阅读 下载PDF
Synthesis of various morphologies of CoFe bimetallic hydroxides for enhanced oxygen evolution reaction performance
6
作者 Liming Yang Yuanbo Cao +7 位作者 Linsong Wang Tao Yang Kang Wang Enhui Wang Xiangtao Yu Hongyang Wang Kuo-Chih Chou Xinmei Hou 《International Journal of Minerals,Metallurgy and Materials》 2025年第8期2024-2033,共10页
CoFe bimetallic hydroxides(CoFe BMHs)find wide applications as excellent catalysts in the field of water splitting.However,no study has systematically investigated the influence of the morphologies of CoFe BMHs on cat... CoFe bimetallic hydroxides(CoFe BMHs)find wide applications as excellent catalysts in the field of water splitting.However,no study has systematically investigated the influence of the morphologies of CoFe BMHs on catalyst performance.In this study,CoFe BMH nanoflowers(CoFe BMH NFs),CoFe BMH nanosheets(CoFe BMH NSHs),CoFe BMH nanorods(CoFe BMH NRs),and CoFe BMH nanospheres(CoFe BMH NSPs)were prepared on nickel foam via a hydrothermal method.CoFe BMH NSHs exhibited the most beneficial catalytic activity.At a current density of 100 mA·cm^(-2),its overpotential for oxygen evolution reaction(OER)was 282 mV,and the overall water splitting voltage was 2.05 V.The double-layer charging capacitance(Cdl)value of CoFe BMH NSHs was the largest in CoFe BMHs,which proves that CoFe BMH NSHs have the largest active area.Furthermore,the active site in the OER process was metal oxyhydroxide(MOOH)through in situ Raman characterization,and the generation of the active substance was an irreversible process.This work provides important insights into the design of catalyst morphologies and offers valuable guidelines for the enhancement of the performance of other catalysts. 展开更多
关键词 bimetallic hydroxides various morphologies hydrogen evolution reaction oxygen evolution reaction overall water splitting
在线阅读 下载PDF
Axial coordinated iron-nitrogen-carbon as efficient electrocatalysts for hydrogen evolution and oxygen redox reactions
7
作者 Yanan Zhou Li Sheng +2 位作者 Lanlan Chen Wenhua Zhang Jinlong Yang 《Chinese Chemical Letters》 2025年第1期637-642,共6页
Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy technology.Herein,based on density functional th... Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy technology.Herein,based on density functional theory(DFT)calculations,we systematically investigate the catalytic activity of iron-nitrogen-carbon based covalent organic frameworks(COF)monolayers with axially coordinated ligands(denotes as Fe N_(4)-X@COF,X refers to axial ligand,X=-SCN,-I,-H,-SH,-NO_(2),-Br,-ClO,-Cl,-HCO_(3),-NO,-ClO_(2),-OH,-CN and-F).The calculated results demonstrate that all the catalysts possess good thermodynamic and electrochemical stabilities.The different ligands axially ligated to the Fe active center could induce changes in the charge of the Fe center,which further regulates the interaction strength between intermediates and catalysts that governs the catalytic activity.Importantly,FeN_(4)-SH@COF and Fe N_(4)-OH@COF are efficient bifunctional catalysts for HER and OER,FeN_(4)-OH@COF and FeN_(4)-I@COF are promising bifunctional catalysts for OER and ORR.These findings not only reveal promising bifunctional HER/OER and OER/ORR catalysts but also provide theoretical guidance for designing optimum ironnitrogen-carbon based catalysts. 展开更多
关键词 Axial coordinated ligands DFT calculation Hydrogen evolution reaction Oxygen evolution reaction Oxygen reduction reaction
原文传递
Evolution and generation mechanism of retained oil in lacustrine shales:A combined ReaxFF-MD and pyrolysis simulation perspective
8
作者 Biao Sun Xiao-Ping Liu +3 位作者 Jie Liu Tian Liu Zu-Xian Hua Wen-Di Peng 《Petroleum Science》 2025年第1期29-41,共13页
To accurately investigate the evolution characteristics and generation mechanism of retained oil,the study analyzed organic-rich lacustrine shale samples from the Paleogene Kongdian Formation in Cangdong Sag,Bohai Bay... To accurately investigate the evolution characteristics and generation mechanism of retained oil,the study analyzed organic-rich lacustrine shale samples from the Paleogene Kongdian Formation in Cangdong Sag,Bohai Bay Basin.This analysis involves Rock-Eval pyrolysis,pyrolysis simulation experiments,Gas Chromatograph Mass Spectrometer(GC-MS),and reactive molecular dynamics simulations(ReaxFF).The results revealed the retained oil primarily consisted of n-alkanes with carbon numbers ranging from C14 to C36.The generation of retained oil occurred through three stages.A slow growth stage of production rate was observed before reaching the peak of oil production in Stage Ⅰ.Stage Ⅱ involved a rapid increase in oil retention,with C12-C17 and C24-C32 serving as the primary components,increasing continuously during the pyrolysis process.The generation process involved the cleavage of weak bonds,including bridging bonds(hydroxyl,oxy,peroxy,imino,amino,and nitro),ether bonds,and acid amides in the first stage(Ro=0.50%-0.75%).The carbon chains in aromatic ring structures with heteroatomic functional groups breaks in the second stage(R_(o)=0.75%-1.20%).In the third stage(R_(o)=1.20%-2.50%),the ring structures underwent ring-opening reactions to synthesize iso-short-chain olefins and radicals,while further breakdown of aliphatic chains occurred.By coupling pyrolysis simu-lation experiments and molecular simulation technology,the evolution characteristics and bond breaking mechanism of retained oil in three stages were revealed,providing a reference for the for-mation and evolution mechanism of retained oil. 展开更多
关键词 Lacustrine shale Retained oiliness evolution Pyrolysis simulation experiments ReaxFF molecular dynamics Hydrocarbon generation evolution
原文传递
Deep-sea Evolution Unlocked
9
《Bulletin of the Chinese Academy of Sciences》 2025年第1期15-15,共1页
The hadal zone-Earth’s deepest oceanic trenches below 6,000 meters-has long been considered a lifeless abyss.Researchers from the Institute of Hydrobiology(IHB)and the Institute of Deep-Sea Science and Engineering(ID... The hadal zone-Earth’s deepest oceanic trenches below 6,000 meters-has long been considered a lifeless abyss.Researchers from the Institute of Hydrobiology(IHB)and the Institute of Deep-Sea Science and Engineering(IDSSE),both under the Chinese Academy of Sciences,together with collaborators from Northwestern Polytechnical University,recently decoded how fish thrive in this extreme realm through two evolutionary pathways while uncovering alarming traces of human pollution in these pristine ecosystems.Their discovery was published in Cell on March 6,2025. 展开更多
关键词 human pollution hadal zone deep sea evolution evolutionary pathways oceanic trenches fish
在线阅读 下载PDF
Evolutionary balance between genomic conservation and coral reef adaptation in the yellow boxfish(Ostracion cubicus)
10
作者 Shui-Mu Hu Zhi-Xiong Zhou +5 位作者 Jun-Yi Yang Zhou Jiang Fei Pu Qing-Ming Qu Tao Zhou Peng Xu 《Zoological Research》 2025年第3期661-674,共14页
The yellow boxfish(Ostracion cubicus)exhibits a combination of derived morphological traits specialized for coral reef environments and ancestral characteristics,including a fused dermal plate.Contradictory evolutiona... The yellow boxfish(Ostracion cubicus)exhibits a combination of derived morphological traits specialized for coral reef environments and ancestral characteristics,including a fused dermal plate.Contradictory evolutionary evidence hinders true classification of O.cubicus.To clarify its evolutionary position within Tetraodontiformes,a chromosome-level genome assembly was generated,representing the most contiguous and complete genome to date for this lineage.Notably,O.cubicus possessed the largest genome within the order Tetraodontiformes,primarily due to extensive transposable element expansion.Phylogenetic analysis based on 19 whole genomes and 131 mitochondrial genomes resolved Tetraodontiformes into three major sister groups(Ostraciidae-Molidae,Tetraodontidae,and Balistidae-Monacanthidae).Comparative genomic evidence indicated that O.cubicus diverged early from the common ancestor of modern Tetraodontiformes and retained the highest number of HOX genes among surveyed taxa.Although overall genomic architecture was largely conserved,certain genetic and environmental changes may have contributed to its phenotypic adaptations,including climate cooling during the Miocene-Pliocene Transition,recent DNA and long interspersed nuclear element(LINE)transposon bursts,lineage-specific chromosomal rearrangements,and gene family expansion.Many positively selected genes and rapidly evolving genes were associated with skeletal development,including bmp7,egf7,and bmpr2.Transcriptomic comparisons between carapace and tail skin revealed various candidate genes and pathways related to carapace formation,such as postn,scpp1,and components of the TGF-βsignaling pathway.A derived amino acid substitution in eda,coupled with protein structural modeling,suggested potential molecular convergence in dermal plate formation among teleosts.These findings provide novel insights into the genomic and developmental basis of carapace evolution and coral reef-adaptation in O.cubicus,offering a strong case for evolutionary balance between genomic conservation with regulatory innovation to achieve coral reef specialization. 展开更多
关键词 Ostracion cubicus Comparative genomics evolutionary genomics Dermal carapace Convergent evolution
在线阅读 下载PDF
Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis 被引量:1
11
作者 Jie Wang Wei Wang +4 位作者 Xuheng Chen Junfang Bao Qiuyue Hao Heng Zheng Runsheng Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期58-69,共12页
The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the micro... The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%. 展开更多
关键词 low-carbon ironmaking iron coke GASIFICATION structural evolution kinetic model
在线阅读 下载PDF
Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:4
12
作者 Long Weimin 《稀有金属材料与工程》 北大核心 2025年第4期837-853,共17页
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ... Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects. 展开更多
关键词 design of brazing filler metals design guidelines for composition Ag based brazing filler metals eutectic structures evolution
原文传递
Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption 被引量:1
13
作者 Zizhuang He Lingzi Shi +6 位作者 Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande Gao Panbo Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期191-204,共14页
Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significan... Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase evolution.Herein,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation process.The results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial polarization.Moreover,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic diffraction.Specifically,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon matrix.This design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption. 展开更多
关键词 Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption
在线阅读 下载PDF
Ru⁃doped Co_(3)O_(4)/reduced graphene oxide:Preparation and electrocatalytic oxygen evolution property 被引量:1
14
作者 TIAN Tian ZHOU Meng +5 位作者 WEI Jiale LIU Yize MO Yifan YE Yuhan JIA Wenzhi HE Bin 《无机化学学报》 北大核心 2025年第2期385-394,共10页
Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then... Binary composites(ZIF-67/rGO)were synthesized by one-step precipitation method using cobalt nitrate hexahydrate as metal source,2-methylimidazole as organic ligand,and reduced graphene oxide(rGO)as carbon carrier.Then Ru3+was introduced for ion exchange,and the porous Ru-doped Co_(3)O_(4)/rGO(Ru-Co_(3)O_(4)/rGO)composite electrocatalyst was prepared by annealing.The phase structure,morphology,and valence state of the catalyst were analyzed by X-ray powder diffraction(XRD),scanning electron microscope(SEM),transmission electron microscopy(TEM),and X-ray photoelectron spectroscopy(XPS).In 1 mol·L^(-1)KOH,the oxygen evolution reaction(OER)performance of the catalyst was measured by linear sweep voltammetry,cyclic voltammetry,and chronoamperometry.The results show that the combination of Ru doping and rGO provides a fast channel for collaborative electron transfer.At the same time,rGO as a carbon carrier can improve the electrical conductivity of Ru-Co_(3)O_(4)particles,and the uniformly dispersed nanoparticles enable the reactants to diffuse freely on the catalyst.The results showed that the electrochemical performance of Ru-Co_(3)O_(4)/rGO was much better than that of Co_(3)O_(4)/rGO,and the overpotential of Ru-Co_(3)O_(4)/rGO was 363.5 mV at the current density of 50 mA·cm^(-2). 展开更多
关键词 metal-organic framework GRAPHENE ELECTROCATALYST oxygen evolution reaction
在线阅读 下载PDF
P,N co-doped hollow carbon nanospheres prepared by micellar copolymerization for increased hydrogen evolution in alkaline water 被引量:1
15
作者 HAN Yi-meng XIONG Hao +2 位作者 YANG Jia-ying WANG Jian-gan XU Fei 《新型炭材料(中英文)》 北大核心 2025年第1期211-221,共11页
The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alka... The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds. 展开更多
关键词 Alkaline hydrogen evolution ELECTROCATALYSTS Hollow carbon nanospheres Dual atoms doping Combined effect
在线阅读 下载PDF
Metal-organic framework-derived sulfur-doped iron-cobalt tannate nanorods for efficient oxygen evolution reaction performance 被引量:1
16
作者 ZHAI Haoying WEN Lanzong +3 位作者 LIAO Wenjie LI Qin ZHOU Wenjun CAO Kun 《无机化学学报》 北大核心 2025年第5期1037-1048,共12页
Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nano... Sulfur-doped iron-cobalt tannate nanorods(S-FeCoTA)derived from metal-organic frameworks(MOFs)as electrocatalysts were synthesized via a one-step hydrothermal method.The optimized S-FeCoTA was interlaced by loose nanorods,which had many voids.The S-FeCoTA catalysts exhibited excellent electrochemical oxygen evolution reaction(OER)performance with a low overpotential of 273 mV at 10 mA·cm^(-2)and a small Tafel slope of 36 mV·dec^(-1)in 1 mol·L^(-1)KOH.The potential remained at 1.48 V(vs RHE)at 10 mA·cm^(-2)under continuous testing for 15 h,implying that S-FeCoTA had good stability.The Faraday efficiency of S-FeCoTA was 94%.The outstanding OER activity of S-FeCoTA is attributed to the synergistic effects among S,Fe,and Co,thus promoting electron transfer,reducing the reaction kinetic barrier,and enhancing the OER performance. 展开更多
关键词 hydrothermal method tannic acid metal‑organic framework ELECTROCATALYSIS oxygen evolution reaction
在线阅读 下载PDF
Prediction of microstructure evolution of ZK61 alloy during hot spinning by internal state variable model 被引量:2
17
作者 Jin-qi PAN Wen-cong ZHANG +3 位作者 Jian-lei YANG Song-hui WANG Yong WU Huan LI 《Transactions of Nonferrous Metals Society of China》 2025年第1期126-142,共17页
An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of t... An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of the internal variables were considered in this ISV model,and the parameters were optimized by genetic algorithm.After validation,the ISV model was used to simulate the evolution of grain size(GS)and dynamic recrystallization(DRX)fraction during hot spinning via Abaqus and its subroutine Vumat.By comparing the simulated results with the experimental results,the application of the ISV model was proven to be reliable.Meanwhile,the strength of the thin-walled spun ZK61 tube increased from 303 to 334 MPa due to grain refinement by DRX and texture strengthening.Besides,some ultrafine grains(0.5μm)that played an important role in mechanical properties were formed due to the proliferation,movement,and entanglement of dislocations during the spinning process. 展开更多
关键词 internal state variable model hot spinning ZK61 alloy finite element simulation texture evolution
在线阅读 下载PDF
Tailoring the morphology and charge transfer pathways of ultrathin Cd_(0.8)Zn_(0.2)S nanosheets via ionic liquid-modified Ti_(3)C_(2)MXenes towards remarkable photocatalytic hydrogen evolution 被引量:2
18
作者 Qianqian Hu Haiyan Yin +5 位作者 Yifan Liu Abdusalam Ablez Zhuangzhuang Wang Yue Zhan Chengfeng Du Xiaoying Huang 《Journal of Materials Science & Technology》 2025年第1期47-59,共13页
Small-sized Cd_(x) Zn_(1-x) S solid solution nanomaterial is an important candidate for efficient photocatalytic hydrogen evolution(PHE),but it still suffers from easy agglomeration,severe photo corrosion,and fast pho... Small-sized Cd_(x) Zn_(1-x) S solid solution nanomaterial is an important candidate for efficient photocatalytic hydrogen evolution(PHE),but it still suffers from easy agglomeration,severe photo corrosion,and fast photogenerated electron-hole recombination.To tackle these issues,herein,we propose a new strategy to modify Cd_(x) Zn_(1-x) S nanoreactors by the simultaneous utilization of ionic-liquid-assisted morphology engineering and MXene-incorporating method.That is,we designed and synthesized a novel hierarchi-cal Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) Schottky junction composite through the in-situ deposition of ultrathin Cd_(0.8) Zn_(0.2) S nanosheets on unique IL-modified Ti_(3) C_(2) MXenes by a one-pot solvothermal method for efficiently PHE.The unique construction strategy tailors the thickness of ultrathin Cd_(0.8) Zn_(0.2) S nanosheets and prevents them from stacking and agglomeration,and especially,optimizes their charge transfer pathways during the photocatalytic process.Compared with pristine Cd_(0.8) Zn_(0.2) S nanosheets,Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) has abun-dant photogenerated electrons available on the Ti_(3) C_(2) surface for proton reduction reaction,owing to the absence of deep-trapped electrons,suppression of electron-hole recombination in Cd_(0.8) Zn_(0.2) S and high-efficiency charge separation at the Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) Schottky junction interface.Moreover,the hy-drophilicity,electrical conductivity,visible-light absorption capacity,and surficial hydrogen desorption of Cd_(0.8) Zn_(0.2) S/Ti_(3) C_(2) heterostructure are significantly improved.As a result,the heterostructure exhibits out-standing photocatalytic stability and super high apparent quantum efficiency,being rendered as one of the best noble-metal-free Cd-Zn-S-based photocatalysts.This work illustrates the mechanisms of mor-phology control and heterojunction construction in controlling the catalytic behavior of photocatalysts and highlights the great potential of the IL-assisted route in the synthesis of high-performance MXene-based heterostructures for photocatalytic hydrogen evolution. 展开更多
关键词 Ionic liquid Ultrathin Cd_(0.8)Zn_(0.2)S nanosheets MXene Schottky junction Photoexcited charge separation Photocatalytic H_(2)evolution
原文传递
Mechanical properties and microstructure evolution of 1800 MPa grade low alloy ultrahigh strength steel during quenching and tempering process 被引量:1
19
作者 Tong Wang Yang-xin Wang +2 位作者 Chun-dong Hu Peng-min Cao Han Dong 《Journal of Iron and Steel Research International》 2025年第6期1691-1700,共10页
The characterization techniques were employed like transmission electron microscope,X-ray diffraction and microstructural characterization to investigate microstructural evolution and impact of precipitate-phase preci... The characterization techniques were employed like transmission electron microscope,X-ray diffraction and microstructural characterization to investigate microstructural evolution and impact of precipitate-phase precipitation on strength and toughness of a self-developed 32Si_(2)CrNi_(2)MoVNb steel during the quenching and tempering process.Research outputs indicated that the steel microstructure under the quenching state could be composed of martensite with a high dislocation density,a small amount of residual austenite,and many dispersed spherical MC carbides.In details,after tempering at 200℃,fine needle-shapedε-carbides would precipitate,which may improve yield strength and toughness of the steel.However,as compared to that after tempering at 200℃,the average length of needle-shapedε-carbides was found to increase to 144.1±4 from 134.1±3 nm after tempering at 340℃.As a result,the yield strength may increase to 1505±40 MPa,and the impact absorption energy(V-notch)may also decrease.Moreover,after tempering at 450℃,thoseε-carbides in the steel may transform into coarse rod-shaped cementite,and dislocation recoveries at such high tempering temperature may lead to decrease of strength and toughness of the steel.Finally,the following properties could be obtained:a yield strength of 1440±35 MPa,an ultimate tensile strength of 1864±50 MPa and an impact absorption energy of 45.9±4 J,by means of rational composition design and microstructural control. 展开更多
关键词 STRENGTH TOUGHNESS CARBIDE Microstructure evolution mechanism
原文传递
(Meta)transcriptomic Insights into the Role of Ticks in Poxvirus Evolution and Transmission:A Multicontinental Analysis 被引量:1
20
作者 Yuxi Wang Jingjing Hu +10 位作者 Jingjing Hou Xiaojie Yuan Weijie Chen Yanjiao Li Qile Gao Yue Pan Shuiping Lu Qi Chen Siru Hu Zhongjun Shao Chenglong Xiong 《Biomedical and Environmental Sciences》 2025年第9期1058-1070,I0001,共14页
Objective Poxviruses are zoonotic pathogens that infect humans,mammals,vertebrates,and arthropods.However,the specific role of ticks in transmission and evolution of these viruses remains unclear.Methods Transcriptomi... Objective Poxviruses are zoonotic pathogens that infect humans,mammals,vertebrates,and arthropods.However,the specific role of ticks in transmission and evolution of these viruses remains unclear.Methods Transcriptomic and metatranscriptomic raw data from 329 sampling pools of seven tick species across five continents were mined to assess the diversity and abundance of poxviruses.Chordopoxviral sequences were assembled and subjected to phylogenetic analysis to trace the origins of the unblasted fragments within these sequences.Results Fifty-eight poxvirus species,representing two subfamilies and 20 genera,were identified,with 212 poxviral sequences assembled.A substantial proportion of AT-rich fragments were detected in the assembled poxviral genomes.These genomic sequences contained fragments originating from rodents,archaea,and arthropods.Conclusion Our findings indicate that ticks play a significant role in the transmission and evolution of poxviruses.These viruses demonstrate the capacity to modulate virulence and adaptability through horizontal gene transfer,gene recombination,and gene mutations,thereby promoting co-existence and co-evolution with their hosts.This study advances understanding of the ecological dynamics of poxvirus transmission and evolution and highlights the potential role of ticks as vectors and vessels in these processes. 展开更多
关键词 POXVIRUS TICK evolution Horizontal gene transfer Gene recombination Gene regulation
暂未订购
上一页 1 2 250 下一页 到第
使用帮助 返回顶部