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China's economic development stage and its spatiotemporal evolution: A prefectural-level analysis 被引量:16
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作者 QI Yuanjing YANG Yu JIN Fengjun 《Journal of Geographical Sciences》 SCIE CSCD 2013年第2期297-314,共18页
As important mechanisms of regional strategy and policy, prefecture-level regions have played an increasingly significant role in the development of China's economy. However, little research has grasped the essence o... As important mechanisms of regional strategy and policy, prefecture-level regions have played an increasingly significant role in the development of China's economy. However, little research has grasped the essence of the economic development stage and the spatio-temporal evolution process at the prefecture level; this may lead to biased policies and their ineffective implementations. Based on Chenery's economic development theory, this paper identifies China's economic development stages at both national and prefectural levels. Both the Global Moran I index and the Getis-Ord Gi* index are employed to investigate the spatio-temporal evolution of China's economic development from 1990 to 2010. Major conclusions can be drawn as follows. (1) China's economic development is generally in the state of agglomeration. It entered the Primary Production Stage in 1990, and the Middle Industrialized Stage in 2010, with a 'balanced-unbalanced-gradually rebalanced' pattern in the process. (2) China's rapid economic growth experienced a spatial shift from the coastal areas to the the inland areas. Most advanced cities in mid-western China can be roughly categorized into regional hub cities and resource-dependent cities. (3) Hot spots in China's economy moved northward and westward. The interactions between cities and prefectures became weaker in Eastern China, while cities and prefectures in Central and Western China were still at the stage of individual development, with limited effect on the surrounding cities. (4) While the overall growth rate of China's economy has gradually slowed down during the past two decades, the growth rate of cities and prefectures in Central and Western China was much faster than those in coastal areas. (5) Areas rich in resources, such as Xinjiang and Inner Mongolia, have become the new hot spots of economic growth in recent years. For these regions, however, more attention needs to be paid to their unbalanced industrial structures and the lagging social development against the backdrop of the rapid economic growth, driven predominantly by the exploitation of resources. 展开更多
关键词 economic development stage spatial pattern spatio-temporal evolution prefectural-level regions
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Habitat-dependent diversification and parallel molecular evolution: Water scavenger beetles as a case study
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作者 Ke-Qing SONG Huai-Jun XUE +7 位作者 Rolf G BEUTEL Ming BAI Dong-Ju BIAN Jie LIU Yong-Ying RUAN Wen-Zhu LI Feng-Long JIA Xing-Ke YANG 《Current Zoology》 SCIE CAS CSCD 2014年第5期561-570,共10页
Habitat shift is a key innovation that has contributed to the extreme diversification of insects. Most groups are well-adapted to more or less specific environments and shifts usually only happen between similar habit... Habitat shift is a key innovation that has contributed to the extreme diversification of insects. Most groups are well-adapted to more or less specific environments and shifts usually only happen between similar habitats. To colonize a pro- foundly different habitat type does not only present ecological opportunities but also great challenges. We used Hydrophiloidea (water scavenger beetles) as a system to study transitions between terrestrial and aquatic environments. We estimated the diversi- fication rate of different clades using phylogenetic trees based on a representative taxon sampling and six genes. We also investi- gated possible evolutionary changes in candidate genes following habitat shifts. Our results suggest that the diversification rate is relatively slow (0.039-0.050 sp/My) in the aquatic lineage, whereas it is distinctly increased in the secondarily terrestrial clade (0.055-0.075 sp/My). Our results also show that aquatic species have a G (Glycine) or S (Serine) amino acid at a given site of COI, while terrestrial species share an A (Alanine) amino acid with terrestrial outgroups. This indicates that habitat factors may create selection pressure on the evolution of functional genes and cause homoplasy in molecular evolution [Current Zoology 60 (5): 561-570, 2014 ] 展开更多
关键词 Hydrophiloidea Habitat shift Diversification rate Parallel molecular evolution
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Maritime Clusters' Evolution: A Digital Innovation Model
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作者 Maria A. Lambrou 《Journal of Shipping and Ocean Engineering》 2016年第6期364-375,共12页
Maritime cluster is a well-established and productively researched theme by maritime policy and economics scholars. Maritime cluster's evolution is an under-investigated area, with ramifications in maritime policy an... Maritime cluster is a well-established and productively researched theme by maritime policy and economics scholars. Maritime cluster's evolution is an under-investigated area, with ramifications in maritime policy and business decision-making. In this paper, we study the evolutionary formation of maritime clusters, in the contemporary European blue economy context. We examine pertinent factors for the sustainable development of maritime clusters, with a strong technical, service and market innovation orientation. We merely examine the significance of legislative, financial, business networking and knowledge management related components. Qualitative empirical testing of the theoretical premises is performed for the Spanish, Italian, Greek and Cypriot cluster entities. 展开更多
关键词 Maritime cluster cluster evolution digital innovation.
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Post-synthetic modification strategy to construct Co-MOF composites for boosting oxygen evolution reaction activity
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作者 ZHENG Haifeng GUO Xingzhe +5 位作者 WEI Yunwei WANG Xinfang QI Huimin YAN Yuting ZHANG Jie LI Bingwen 《无机化学学报》 北大核心 2026年第1期193-202,共10页
The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecul... The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276. 展开更多
关键词 PYRENE metal-organic frameworks composite catalyst oxygen evolution reaction density functional theory
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CoMoNiO-S/nickel foam heterostructure composite for efficient oxygen evolution catalysis performance
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作者 YANG Hong SHAO Shengjuan +2 位作者 LI Baoyi LU Yifan LI Na 《无机化学学报》 北大核心 2026年第1期203-215,共13页
A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and... A composite electrocatalyst,CoMoNiO-S/NF-110(NF is nickel foam),was synthesized through electrodeposition,followed by pyrolysis and then the vulcanization process.CoMoNiO-S/NF-110 exhibited a structure where Ni3S2 and Mo2S3 nanoparticles were integrated at the edges of Co3O4 nanosheets,creating a rich,heterogeneous interface that enhances the synergistic effects of each component.In an alkaline electrolyte,the synthesized CoMoNiO-S/NF-110 exhibited superior electrocatalytic performance for oxygen evolution reaction(OER),achieving current densities of 100 and 200 mA·cm^(-2) with low overpotentials of 199.4 and 224.4 mV,respectively,outperforming RuO2 and several high-performance Mo and Ni-based catalysts.This excellent performance is attributed to the rich interface formed between the components and active sites exposed by the defect structure. 展开更多
关键词 oxygen evolution reaction VULCANIZATION composite electrocatalyst MoNi-based catalyst
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S-scheme unidirectional transmission of CdS-CuO heterojunction benefits for superior photocatalytic hydrogen evolution efficiency
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作者 ZHAO Haiting YAN Zheng +2 位作者 LIU Yang JIANG Longde LUAN Jingde 《燃料化学学报(中英文)》 北大核心 2026年第1期1-14,共14页
The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ... The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion. 展开更多
关键词 photocatalytic hydrogen evolution CdS-CuO S-scheme heterojunction electron directional transmission interfacial electric field DFT calculation
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The historical evolution of the Serbisütherapy in traditional Mongolian medicine,from its origins to contemporary practice
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作者 Mei-Ri Na Manda Manda +1 位作者 Temuqile Temuqile De-Zhi Yang 《History and Philosophy of Medicine》 2026年第1期43-48,共6页
Serbisütherapy(ST)is a distinctive external treatment modality within traditional Mongolian medicine(TMM),historically developed within a nomadic cultural framework.This study presents a comprehensive philologica... Serbisütherapy(ST)is a distinctive external treatment modality within traditional Mongolian medicine(TMM),historically developed within a nomadic cultural framework.This study presents a comprehensive philological and historical analysis of ST,tracing its evolution from early battlefield applications to contemporary clinical use.By critically examining classical Mongolian medical texts alongside modern case studies,we aim to systematize ST’s therapeutic methods,indications,and limitations,while exploring its mechanisms of action through both traditional theory and modern biomedical perspectives.ST has undergone significant transformation,shifting from whole-body cavity immersion in the 13th century to targeted,organ-specific applications in modern practice.Its four primary methods–Covering,Mounted,Organ Placement,and Suction–demonstrate efficacy in treating cold-natured diseases,musculoskeletal disorders,gynecological conditions,and certain emergencies.ST embodies the core principles of TMM,particularly the balance of the“Three Roots”and the correction of cold-induced pathologies through heat.Despite challenges related to standardization,cultural translation,and regulatory acceptance,ST holds translational potential for integrative medicine.Future research should prioritize mechanistic validation,clinical standardization,and the development of biocompatible thermal technologies to bridge traditional practice with modern healthcare systems. 展开更多
关键词 Serbisütherapy traditional Mongolian medicine THERMOTHERAPY historical evolution integrative medicine
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Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:6
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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
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Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis 被引量:1
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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
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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption 被引量:1
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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
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Ru⁃doped Co_(3)O_(4)/reduced graphene oxide:Preparation and electrocatalytic oxygen evolution property 被引量:1
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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
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P,N co-doped hollow carbon nanospheres prepared by micellar copolymerization for increased hydrogen evolution in alkaline water 被引量:1
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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
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Metal-organic framework-derived sulfur-doped iron-cobalt tannate nanorods for efficient oxygen evolution reaction performance 被引量:1
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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
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Spatial Evolution Characteristics and Influencing Factors of Urban Green Innovation in China 被引量:3
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作者 PENG Wenbin SU Xinyi TANG Yueliang 《Chinese Geographical Science》 2025年第2期234-249,共16页
Cities are important carriers of green innovation.The foundation for accelerating China's ecological civilization construction and fostering regionally coordinated and sustainable development is quantitative analy... Cities are important carriers of green innovation.The foundation for accelerating China's ecological civilization construction and fostering regionally coordinated and sustainable development is quantitative analysis of the spatial evolution pattern and influencing factors of urban green innovation,as well as revealing the development differences between regions.This study's research object includes 284 Chinese cities that are at the prefecture level or above,excluding Xizang,Hong Kong,Macao,and Taiwan of China due to incomplete data.The spatial evolution characteristics of urban green innovation in China between 2005 and 2021 are comprehensively described using the gravity center model and boxplot analysis.The factors that affect urban green innovation are examined using the spatial Durbin model(SDM).The findings indicate that:1)over the period of the study,the gravity center of urban green innovation in China has always been distributed in the Henan-Anhui border region,showing a migration characteristic of‘initially shifting northeast,subsequently southeast',and the migration speed has gradually increased.2)Although there are also noticeable disparities in east-west,the north-south gap is the main cause of the shift in China's urban green innovation gravity center.The primary areas of urban green innovation in China are the cities with green innovation levels higher than the median.3)The main influencing factor of urban green innovation is the industrial structure level.The effect of the financial development level,the government intervention level,and the openness to the outside world degree on urban green innovation is weakened in turn.The environmental regulation degree is not truly influencing urban green innovation.The impact of various factors on green innovation across cities of different sizes,exhibiting heterogeneity.This study is conducive to broadening the academic community's comprehension of the spatial evolution characteristics of urban green innovation and offering a theoretical framework for developing policies for the all-encompassing green transformation of social and economic growth. 展开更多
关键词 urban green innovation spatial evolution spatial Durbin model China
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Recent advancements in noble-metal electrocatalysts for alkaline hydrogen evolution reaction 被引量:2
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作者 Guoliang Gao Guangzhen Zhao +4 位作者 Guang Zhu Bowen Sun Zixu Sun Shunli Li Ya-Qian Lan 《Chinese Chemical Letters》 2025年第1期176-200,共25页
Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to thei... Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial contexts.This review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable development.The initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent advancements.The subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active sites.Ultimately,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER. 展开更多
关键词 Hydrogen evolution reaction Alkaline water electrolysis ELECTROCATALYSTS Noble metal-based Synthesis method Modification strategy
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Prediction of microstructure evolution of ZK61 alloy during hot spinning by internal state variable model 被引量:2
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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
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Laser shock processing of titanium alloys:A critical review on the microstructure evolution and enhanced engineering performance 被引量:2
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作者 Qian Liu Shuangjie Chu +6 位作者 Xing Zhang Yuqian Wang Haiyan Zhao Bohao Zhou Hao Wang Genbin Wu Bo Mao 《Journal of Materials Science & Technology》 2025年第6期262-291,共30页
Titanium(Ti)and its alloys are frequently utilized as critical components in a variety of engineering ap-plications because of their high specific strength and excellent corrosion resistance.Compared to conven-tional ... Titanium(Ti)and its alloys are frequently utilized as critical components in a variety of engineering ap-plications because of their high specific strength and excellent corrosion resistance.Compared to conven-tional surface strengthening technologies,laser shock peening(LSP)has increasingly attracted attention from researchers and industries,since it significantly improves the surface strength,biocompatibility,fa-tigue resistance,and anti-corrosion ability of Ti and its alloys.Despite numerous studies that have been carried out to elucidate the effects of LSP on microstructural evolution and mechanical properties of Ti and its alloys in recent years,a comprehensive review of recent advancements in the field of Ti and its alloys subjected to LSP is still lacking.In this review,the standard LSP and the novel process designs of LSP assisted by thermal,cryogenic,electropulsing and magnetic fields are discussed and compared.Microstructural evolution,with focuses on the dislocation dynamics,deformation twinning,grain refine-ment and surface amorphization,during LSP processing of Ti alloys is reviewed.Furthermore,the en-hanced engineering performance of the L SP-processed(L SPed)Ti alloys,including surface hardness,wear resistance,fatigue life and corrosion resistance are summarized.Finally,this review concludes by present-ing an overview of the current challenges encountered in this field and offering insights into anticipated future trends. 展开更多
关键词 Laser shock peening Titanium alloys Microstructure evolution Mechanical properties
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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
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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
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Mechanical properties and microstructure evolution of 1800 MPa grade low alloy ultrahigh strength steel during quenching and tempering process 被引量:1
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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
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(Meta)transcriptomic Insights into the Role of Ticks in Poxvirus Evolution and Transmission:A Multicontinental Analysis 被引量:1
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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
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