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
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
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
Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a fo...Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.展开更多
Aeolian deposits across the Yarlung Zangbo River Basin on the southern Tibetan Plateau record the landscape and atmospheric evolution of Earth's Third Pole.The complex mountain-basin system exhibits nonlinear resp...Aeolian deposits across the Yarlung Zangbo River Basin on the southern Tibetan Plateau record the landscape and atmospheric evolution of Earth's Third Pole.The complex mountain-basin system exhibits nonlinear responses to climate forcing,complicating the interpretation of its high-altitude environmental dynamics.Investigating the magnetic enhancement mechanism of aeolian deposits offers an opportunity to decipher climate signals.Our analysis of three aeolian sections from the basin indicates that magnetic minerals are predominantly low-coercivity ferrimagnetic minerals,and grain sizes fine from upper to lower reaches due to climate shifts from arid to humid.Magnetic enhancement in the upper reaches primarily originates from dust input,while dust input and pedogenesis contribute variably over time in the middle and lower reaches.Similar complex patterns occur in the Ili basin,a mountain-basin system in northwestern China.They differ from the Chinese Loess Plateau,where long-distance-transported dust is well-mixed and the pedogenic enhancement model is applied,and desert peripheries where short-distance dust is transported and the dust input model is applied.We summarize the magnetic enhancement mechanisms in various settings and offer a new framework for applying magnetic techniques in paleoclimate reconstruction within global mountain-basin systems,which highlights the need for caution in interpreting their magnetic susceptibility records.展开更多
Hydrogen production by electrolysis of water is a key technology to achieve green hydrogen energy economy,but it relies on advanced catalyst materials with high efficiency,stability,and wide pH adaptability.In this st...Hydrogen production by electrolysis of water is a key technology to achieve green hydrogen energy economy,but it relies on advanced catalyst materials with high efficiency,stability,and wide pH adaptability.In this study,Ni,Ru,and Pt ternary metals were embedded into nitrogen-doped hollow carbon spheres(NHCSs)by hydrothermal tandem heat treatment to form ternary supported metal nanoparticles with high dispersion and ultra-small particle size(~1.3 nm),which realized efficient hydrogen evolution from multi-scenario electrocatalytic water splitting.In the whole pH range,the performance of NiRuPt/NHCSs is better than that of commercial Pt/C catalyst,and the overpotentials under alkaline,neutral,and acidic conditions are as low as 15.5,20.0,and 29.5 mV,respectively.Under industrial conditions,NiRuPt/NHCSs also have excellent hydrogen evolution reaction(HER)performance,achieving efficient electrolysis of seawater for hydrogen production,and achieving Ampere-level hydrogen production at low voltage(~1.76 V)on integrated membrane electrode assemblies.Density functional theory(DFT)calculations show that in the NiRuPt ternary metal,the Pt site is conducive to promoting the desorption of*H to form H_(2),the Ru site is conducive to promoting the capture of H_(2)O,and the Ni site is conducive to promoting the dissociation of H_(2)O.Therefore,the formed NiRuPt ternary metal synergistically promotes multi-scenario efficient electrolysis of water to produce hydrogen.This study provides a new idea for the design of multi-component metal/carbon-based composite catalysts,and promotes the development of non-noble metal/noble metal composite catalysts in hydrogen production by electrolysis of water.展开更多
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
Oxygen evolution reaction(OER)is a key step in hydrogen production by water electrolysis technology.How-ever,developing efficient,stable,and low-cost OER electrocatalysts is still challenging.This article presents the...Oxygen evolution reaction(OER)is a key step in hydrogen production by water electrolysis technology.How-ever,developing efficient,stable,and low-cost OER electrocatalysts is still challenging.This article presents the preparation of a series of novel copper iridium nanocatalysts with heterostructures and low iridium content for OER.The electrochemical tests revealed higher OER of Cu@Ir_(0.3) catalyst under acidic conditions with a generated current density of 10 mA/cm^(2) at only 284 mV overpotential.The corresponding OER mass activity was estimated to be 1.057 A/mgIr,a value 8.39-fold higher than that of the commercial IrO_(2).After 50 h of endurance testing,the Cu@Ir_(0.3) catalyst preserved excellent catalytic activity with a negligible rise in overpotential and maintained a good heterostructures.Cu@Ir_(0.3) The excellent OER activity can be attributed to its heterostructure,as con-firmed by density functional theory(DFT)calculations,indicating that Cu@Ir The coupling between isoquanta causes charge redistribution,optimizing the adsorption energy of unsaturated Ir sites for oxygen intermediates and reducing the energy barrier of OER free energy determining the rate step.In summary,this method provides a new approach for designing efficient,stable,and low iridium content OER catalysts.展开更多
Deep insights into electrocatalytic mechanisms are vital for the rational design of catalysts for oxygen evolution reaction(OER).Mechanistically,the OER driven by adsorbate evolution mechanism(AEM)is limited by the li...Deep insights into electrocatalytic mechanisms are vital for the rational design of catalysts for oxygen evolution reaction(OER).Mechanistically,the OER driven by adsorbate evolution mechanism(AEM)is limited by the linear scaling relationship,thereby exhibiting large overpotentials.In the lattice oxygen mechanism(LOM),the OER can be enhanced by enabling direct O_(2)formation.However,this enhancement is accompanied by the generation of oxygen vacancies,which presents a significant challenge to the long-term stability of LOMOER,particularly when operating at high current densities.Recently,the*O-*O coupling mechanism(OCM)has emerged as a promising alternative;it not only breaks the linear scaling relationship but also ensures catalytic stability.This review encapsulates the cutting-edge advancements in electrocatalysts that are grounded in the OCM,offering a detailed interpretation on the foundational principles guiding the design of OCM-OER catalysts.It also highlights recent theoretical investigations combining machine learning(ML)with density functional theory(DFT)calculations to reveal OER mechanisms.At the end of this review,the challenges and opportunities associated with OCM-OER electrocatalysts are discussed.展开更多
The dissimilar 2B06 and 7B04 Al alloy joints were prepared by refill friction stir spot welding(RFSSW),and the microstructural evolution and corrosion behavior of the joints were investigated.Based on microstructural ...The dissimilar 2B06 and 7B04 Al alloy joints were prepared by refill friction stir spot welding(RFSSW),and the microstructural evolution and corrosion behavior of the joints were investigated.Based on microstructural analysis,the welded joints exhibit distinct microstructural zones,including the stir zone(SZ),thermomechanically affected zone(TMAZ),and heat-affected zone(HAZ).The grain size of each zone is in the order of HAZ>TMAZ>SZ.Notably,the TMAZ and HAZ contain significantly larger secondary-phase particles compared to the SZ,with particle size in the HAZ increasing at higher rotational speeds.Electrochemical tests indicate that corrosion susceptibility follows the sequence of HAZ>TMAZ>SZ>BM,with greater sensitivity observed at increased rotational speeds.Post-corrosion mechanical performance degradation primarily arises from crevice corrosion at joint overlaps,but not from the changes in the microstructure.展开更多
Heterostructure engineering has emerged as a promising strategy to enhance the electrochemical CO_(2)reduction reaction(CO_(2)RR)by optimizing interfacial electron transfer.Herein,we report a novel octahedral SnS_(2)/...Heterostructure engineering has emerged as a promising strategy to enhance the electrochemical CO_(2)reduction reaction(CO_(2)RR)by optimizing interfacial electron transfer.Herein,we report a novel octahedral SnS_(2)/SnO_(2)heterojunction catalyst synthesized via an ion-exchange vulcanization method,which achieves exceptional activity and selectivity for CO_(2)-toformate conversion.Through in-situ Raman spectroscopy,ex-situ X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS),we demonstrate that the octahedral SnS_(2)/SnO_(2)heterojunction dynamically restructures into a sulfur-doped Sn/SnO_(2)(Sn(S)/SnO_(2))heterostructure under operating conditions.Density functional theory(DFT)calculations reveal that the Sn(S)/SnO_(2)interface facilitates electron transfer from SnO_(2)to metallic Sn(S),generating a built-in electric field that stabilizes Sn^(4+)in SnO_(2)and accelerates proton-coupled electron transfer to*OCHO intermediates.Consequently,the catalyst achieves a formate Faradaic efficiency exceeding 90% over a broad potential window(-0.6 to -1.0 V vs.reversible hydrogen electrode(RHE))with a high partial current density of -280 mA·cm^(-2),surpassing most reported Sn-based catalysts.This work elucidates the structural dynamics and interfacial enhancement mechanisms of heterojunction catalysts,offering a rational design principle for advanced CO_(2)RR electrocatalysts.展开更多
Chinese Neogene Rhinocerotidae has quite a complete record and its temporalrange is the Early Miocene to Late Pliocene. The samples include 25 species in 4 tribes of 2subfamilies. They are used as a foundation for the...Chinese Neogene Rhinocerotidae has quite a complete record and its temporalrange is the Early Miocene to Late Pliocene. The samples include 25 species in 4 tribes of 2subfamilies. They are used as a foundation for the study of the evolution of the family and itsrelation to climatic changes. Taxonomic diversity, new records and extinctions are estimated foreach Chinese Neogene mammal faunal unit (NMU). The diversity of Chinese Rhinocerotidae variesnoticeably throughout the Neogene and is recognized within five stages: the Middle Miocene and LateMiocene are stages of high diversity and the Early Miocene, early Late Miocene and Pliocene arestages of low diversity. Rhinocerotid diversity and morphology are closely related to environmentalfactors and particularly sensitive to changes in ambient temperature and humidity. Theinterpretation of climatic variation reflected in the evolution of Rhinocerotidae correspondsprecisely with the conclusions drawn from other workers and provides new evidence for research onthe Neogene terrestrial ecosystem in China.展开更多
The evolution of the inland lakes in arid and semi-arid zones is accorded with the climatic fluctuation. The humid climate is in harmony with the higher water level and greater lake water quantity budget while arid cl...The evolution of the inland lakes in arid and semi-arid zones is accorded with the climatic fluctuation. The humid climate is in harmony with the higher water level and greater lake water quantity budget while arid climate is in correspondence with the lower water level and little water budget. Based on the analysis of the lake fluctuation and lake budget change, with the aid of the data of geom’orphology, palynology, sedimentology and chronology, It is found that the climate experienced a warm and humid period during 7000-3500 yr. B. P. and showed a drying and warming trend in the last century in the Central Asia.展开更多
Based on the sand dust storms data and climatic data in 12 meteorological stations around sand dust storm originating areas of the Taklimakan Desert, we analyzed the trends of the number of dust storm days from 1960 t...Based on the sand dust storms data and climatic data in 12 meteorological stations around sand dust storm originating areas of the Taklimakan Desert, we analyzed the trends of the number of dust storm days from 1960 to 2005 as well as their correlations with temperature, precipitation, wind speed and the number of days with mean wind speed 〉 5 m/s. The results show that the frequency of dust storm events in the Taklimakan region decreased with the elapse of time. Except Ruoqiang and Minfeng, in the other 10 meteorological stations, the frequency of dust storm events reduces, and in 4 meteorological stations of Kuqa, Korla, Kalpin and Hotan, the frequency of dust storm events distinctly decreases. The temperature has an increasing trend, while the average wind speed and the number of days with mean wind speed ≥ 5 m/s have decreasing trends. The correlation analysis between the number of days of dust storms and climatic parameters demonstrates that wind speed and the number of days with mean wind speed 〉 5 m/s have strong positive correlation with the number of days of dust storms, with the correlations coefficients being 0.743 and 0.720 (p〈0.01), respectively, which indicates that strong wind is the direct factor resulting in sand dust storms. Whereas precipitation has significant negative correlation with the number of days of dust storms (p〈0.01), and the prior annual precipitation has also negative correlation, which indicates that the prior precipitation restrains the occurrence of sand dust storms, but this restraining action is weaker than the same year's precipitation. Temperature has negative correlation with the number of dust storm days, with a correlations coefficient of -0.433 (p〈0.01), which means that temperature change also has impacts on the occurrence of dust storm events in the Taklimakan region.展开更多
The Qaidam Basin is. a tectonically controlled depression at 2700 m altitude on the northern margin of the Tibet Plateau. A succession of Neogene clastic sediments indicates lake depocentre migration from NW to SE. To...The Qaidam Basin is. a tectonically controlled depression at 2700 m altitude on the northern margin of the Tibet Plateau. A succession of Neogene clastic sediments indicates lake depocentre migration from NW to SE. Towards late Pliocene, evaporative conditions developed with formation of gypsum, halite, celestite, mirabilite and bloedite. Continued deformation through Pleistocene developed a series of NW- SE trending domes and troughs. This setting continued to exert a controlling influence on basin and brine evolution and the progressive development of sulfate to chloride brines as, dry conditions intensified in late Pleistocene, at the end of which, extensive flat floors were formed in Dalangtan, Qarhan and other playas.The, model, which was set up based on the synthetic analyses, divides the fluctuating palaeoclimate since 750ka,B. P. into 11 warm and humid stages and 10 dry and cold stages. The water of the lakes evaporated during the dry-cold periods and were freshened during the warm-humid展开更多
In this paper, we make use of the functional spectral analysis to infer the periodicity of paleoclimate in the Hongzuisi section since about 15 ka. Through combined analysis of organic carbon isotope and CaCO\-3 conte...In this paper, we make use of the functional spectral analysis to infer the periodicity of paleoclimate in the Hongzuisi section since about 15 ka. Through combined analysis of organic carbon isotope and CaCO\-3 content, the law of paleoclimatic evolution of the Hongzuisi section is obtained. There were climatic changes from 10 ka to about 0.1 ka over the last 15 ka. Among these cycles, the cycle of several ka is most remarkable. The result indicates that functional spectral analysis is helpful for paleoclimatic study, which can provide useful information about paleoclimatic reconstruction and future forecast.展开更多
As the largest inland lake of China, along with its unique landscape and geographical location, Qinghai Lake has got much atten- tion of the scientists for a long time. The precursors have done substantive researches ...As the largest inland lake of China, along with its unique landscape and geographical location, Qinghai Lake has got much atten- tion of the scientists for a long time. The precursors have done substantive researches by using the lake sediment, which deepen our tmderstanding of the climate changes in this region. Although sand dunes and loess sediment are widely distributed around the lake, so far the researches on geochemical elements from aeolian sediment have been less reported. In this paper, we selected a typical aeolian profile on the east of Qinghai Lake. Based on systematic sampling and analysis of seven major geochemical ele- ments, combined with OSL dating and previous researches, this paper discusses climate changes in the Qinghai Lake area since 12.5 ka B.P.. Our conclusions are: (1) Before 12.5 ka B.P., the climate in this region was dry, cold, and accompanied by strong wind-sand activities. (2) During 12.5-11.9 ka B.P., the climate became warm and wet. However, there was an abrupt climate cooling event during 12.2-11.9 ka B.P., which likely corresponded to the Younger Dryas event. (3) During 11.9 8.0 ka B.P., the climate fluctuated greatly and frequently from warm to cold, and three cooling events occurred. (4) During 8.0-2.6 ka B.P., the climate was warm and humid. (5) Since 2.6 ka B.P., similar to the modem climate, the climate was mainly dry and cold.展开更多
On the basis of lacustrine sedimentary profile of Ebinur Lake,sequences of evolution of paleoclimate and paleoenvironment in Ebinur Lake area have been rebuilt by analysing the sedimentary stratigraphy,bio-stratigraph...On the basis of lacustrine sedimentary profile of Ebinur Lake,sequences of evolution of paleoclimate and paleoenvironment in Ebinur Lake area have been rebuilt by analysing the sedimentary stratigraphy,bio-stratigraphy and gepochemistry as well as the chronological records.The results show that,during the last 10 ha years,the general change trends of the paleoclimate in Ebinur Lake area can be divided into three stages: (1) 10. 2-8.3 ka B. P., a warm-cool dry climate stage;(2) 8.3-3.5 ka B.P.,a warmer moist climate stage (specially,7.3-6. 4 ka B. P.,a relatively stable humid temperate stage);(3) 3. 5 ka B. P.-present, adraught temperate climate stage,similar to the present climate. In addition,there existed clearly several times of secondary undulations of dry-humid climate,i.e. 8.3 ka and 7.3 ka for dry climate展开更多
Two hundred and thirty-five samples collected from Weinan loess section (L2 - S0)have analyzed by TOC (total organic carbon) and pyrolysis hydrocarbons. The curve of TOC with depth has ho set up and compared well with...Two hundred and thirty-five samples collected from Weinan loess section (L2 - S0)have analyzed by TOC (total organic carbon) and pyrolysis hydrocarbons. The curve of TOC with depth has ho set up and compared well with other climatic markers. The main periods of TOC variation of the last 0. 14 Ma are 67.08 ka and 18.29 ka, which is near with the periods of the variation of sunshine, showing that the TOC variation may be controlled by the variation of 65°N sunshine. The distribution of pyrolysis hydrocarbon and its parameters shows that there are two kinds of hydrocarbon associated with climatic change. One is called hydrocarbon pyrolysted directly from organism (pHC2-1) which is in the range of Tmax350℃ - 500℃, and associated with atmospheric water. The other is called carbonate inclusion inclusion (pHC2-2) which is in the range of Tmax 500℃ - 600℃ and formed by evaporation and associated with dry climate. The formula calculating humidity has been deduced Og = pHC2-1/(pHC2-1 + pHC2-2). The range of humidity of the section is 47% - 77% and the reducing is S1-3, S1-2, S0, S1-1, S1-4, S1-2, L1-1, L1-3, and L1-5. And the trend of the humidity is still increasing today.展开更多
文摘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.
文摘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.
文摘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.
基金support from the National Natural Science Foundation of China(Nos.12305373 and 52276220)the Guangzhou Basic Research Program(No.SL2024A04J00234).
文摘Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies.
基金National Natural Science Foundation of China,No.42501182The Open Foundation of Key Laboratory of Western China’s Environmental System,Ministry of Education,Lanzhou Universitythe Fundamental Research Funds for the Central Universities,No.lzujbky-2024-jdzx01。
文摘Aeolian deposits across the Yarlung Zangbo River Basin on the southern Tibetan Plateau record the landscape and atmospheric evolution of Earth's Third Pole.The complex mountain-basin system exhibits nonlinear responses to climate forcing,complicating the interpretation of its high-altitude environmental dynamics.Investigating the magnetic enhancement mechanism of aeolian deposits offers an opportunity to decipher climate signals.Our analysis of three aeolian sections from the basin indicates that magnetic minerals are predominantly low-coercivity ferrimagnetic minerals,and grain sizes fine from upper to lower reaches due to climate shifts from arid to humid.Magnetic enhancement in the upper reaches primarily originates from dust input,while dust input and pedogenesis contribute variably over time in the middle and lower reaches.Similar complex patterns occur in the Ili basin,a mountain-basin system in northwestern China.They differ from the Chinese Loess Plateau,where long-distance-transported dust is well-mixed and the pedogenic enhancement model is applied,and desert peripheries where short-distance dust is transported and the dust input model is applied.We summarize the magnetic enhancement mechanisms in various settings and offer a new framework for applying magnetic techniques in paleoclimate reconstruction within global mountain-basin systems,which highlights the need for caution in interpreting their magnetic susceptibility records.
基金financially supported by the Yunnan Fundamental Research Projects(Nos.202401CF070026 and 202501AT070017)the Scientific Research Fund Project of Yunnan Provincial Education Department(No.2024J0134)+1 种基金the Xingdian Talent Program of Yunnan Province,and the Scientific and Technological Project of Yunnan Precious Metals Laboratory(No.YPML-20240502065)Xinjiang Key Laboratory of Novel Functional Materials Chemistry Open Science Project(No.XJLNFMC-202406).
文摘Hydrogen production by electrolysis of water is a key technology to achieve green hydrogen energy economy,but it relies on advanced catalyst materials with high efficiency,stability,and wide pH adaptability.In this study,Ni,Ru,and Pt ternary metals were embedded into nitrogen-doped hollow carbon spheres(NHCSs)by hydrothermal tandem heat treatment to form ternary supported metal nanoparticles with high dispersion and ultra-small particle size(~1.3 nm),which realized efficient hydrogen evolution from multi-scenario electrocatalytic water splitting.In the whole pH range,the performance of NiRuPt/NHCSs is better than that of commercial Pt/C catalyst,and the overpotentials under alkaline,neutral,and acidic conditions are as low as 15.5,20.0,and 29.5 mV,respectively.Under industrial conditions,NiRuPt/NHCSs also have excellent hydrogen evolution reaction(HER)performance,achieving efficient electrolysis of seawater for hydrogen production,and achieving Ampere-level hydrogen production at low voltage(~1.76 V)on integrated membrane electrode assemblies.Density functional theory(DFT)calculations show that in the NiRuPt ternary metal,the Pt site is conducive to promoting the desorption of*H to form H_(2),the Ru site is conducive to promoting the capture of H_(2)O,and the Ni site is conducive to promoting the dissociation of H_(2)O.Therefore,the formed NiRuPt ternary metal synergistically promotes multi-scenario efficient electrolysis of water to produce hydrogen.This study provides a new idea for the design of multi-component metal/carbon-based composite catalysts,and promotes the development of non-noble metal/noble metal composite catalysts in hydrogen production by electrolysis of water.
基金supported by The China Ethnic Medicine Association Research Grant(No.2023MY055-81)Science and Technology Program of the Joint Fund of Scientific Research for the Public Hospitals of Inner Mongolia Academy of Medical Sciences(2023GLLHD177,2023GLLH0174)Inner Mongolia Autonomous Region Regional Medical Center for Specialized Care(2025).
文摘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.
基金supported by the Major Science and Technology Special Plan of Yunnan Province(Nos.202302AB080012 and 202402AB080004)the National Natural Science Foundation of China(No.22264025)+1 种基金the Basic Research Foundation of Yunnan Province(Nos.202401AS070033 and 202501AT070055)the Reserve talents for young and middleaged academic and technical leaders project of Yunnan Province(No.202405AC350071).
文摘Oxygen evolution reaction(OER)is a key step in hydrogen production by water electrolysis technology.How-ever,developing efficient,stable,and low-cost OER electrocatalysts is still challenging.This article presents the preparation of a series of novel copper iridium nanocatalysts with heterostructures and low iridium content for OER.The electrochemical tests revealed higher OER of Cu@Ir_(0.3) catalyst under acidic conditions with a generated current density of 10 mA/cm^(2) at only 284 mV overpotential.The corresponding OER mass activity was estimated to be 1.057 A/mgIr,a value 8.39-fold higher than that of the commercial IrO_(2).After 50 h of endurance testing,the Cu@Ir_(0.3) catalyst preserved excellent catalytic activity with a negligible rise in overpotential and maintained a good heterostructures.Cu@Ir_(0.3) The excellent OER activity can be attributed to its heterostructure,as con-firmed by density functional theory(DFT)calculations,indicating that Cu@Ir The coupling between isoquanta causes charge redistribution,optimizing the adsorption energy of unsaturated Ir sites for oxygen intermediates and reducing the energy barrier of OER free energy determining the rate step.In summary,this method provides a new approach for designing efficient,stable,and low iridium content OER catalysts.
基金supported by the National Natural Science Foundation of China(Nos.22373063 and 22302005)Fundamental Research Funds for the Central Universities of China(No.GK202203002)+1 种基金China Postdoctoral Science Foundation(No.2023M730044)Technology Innovation Leading Program of Shaanxi(Program No.2023KXJ-007).
文摘Deep insights into electrocatalytic mechanisms are vital for the rational design of catalysts for oxygen evolution reaction(OER).Mechanistically,the OER driven by adsorbate evolution mechanism(AEM)is limited by the linear scaling relationship,thereby exhibiting large overpotentials.In the lattice oxygen mechanism(LOM),the OER can be enhanced by enabling direct O_(2)formation.However,this enhancement is accompanied by the generation of oxygen vacancies,which presents a significant challenge to the long-term stability of LOMOER,particularly when operating at high current densities.Recently,the*O-*O coupling mechanism(OCM)has emerged as a promising alternative;it not only breaks the linear scaling relationship but also ensures catalytic stability.This review encapsulates the cutting-edge advancements in electrocatalysts that are grounded in the OCM,offering a detailed interpretation on the foundational principles guiding the design of OCM-OER catalysts.It also highlights recent theoretical investigations combining machine learning(ML)with density functional theory(DFT)calculations to reveal OER mechanisms.At the end of this review,the challenges and opportunities associated with OCM-OER electrocatalysts are discussed.
基金supported by the National Natural Science Foundation of China (Nos. 52075449, 51975480)。
文摘The dissimilar 2B06 and 7B04 Al alloy joints were prepared by refill friction stir spot welding(RFSSW),and the microstructural evolution and corrosion behavior of the joints were investigated.Based on microstructural analysis,the welded joints exhibit distinct microstructural zones,including the stir zone(SZ),thermomechanically affected zone(TMAZ),and heat-affected zone(HAZ).The grain size of each zone is in the order of HAZ>TMAZ>SZ.Notably,the TMAZ and HAZ contain significantly larger secondary-phase particles compared to the SZ,with particle size in the HAZ increasing at higher rotational speeds.Electrochemical tests indicate that corrosion susceptibility follows the sequence of HAZ>TMAZ>SZ>BM,with greater sensitivity observed at increased rotational speeds.Post-corrosion mechanical performance degradation primarily arises from crevice corrosion at joint overlaps,but not from the changes in the microstructure.
基金the Natural Science Foundation of Jiangsu Province(No.BK20253049)the Science and Technology Program of Xuzhou(No.KC25028)+3 种基金the Basic Science(Natural Science)Research Project of Higher Education Institutions in Jiangsu Province(No.25KJB430013)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.24KJA150003)the National Natural Science Foundation of China(No.22271122)the Xuzhou Key Research and Development Program(Social Development)(No.KC23298).
文摘Heterostructure engineering has emerged as a promising strategy to enhance the electrochemical CO_(2)reduction reaction(CO_(2)RR)by optimizing interfacial electron transfer.Herein,we report a novel octahedral SnS_(2)/SnO_(2)heterojunction catalyst synthesized via an ion-exchange vulcanization method,which achieves exceptional activity and selectivity for CO_(2)-toformate conversion.Through in-situ Raman spectroscopy,ex-situ X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS),we demonstrate that the octahedral SnS_(2)/SnO_(2)heterojunction dynamically restructures into a sulfur-doped Sn/SnO_(2)(Sn(S)/SnO_(2))heterostructure under operating conditions.Density functional theory(DFT)calculations reveal that the Sn(S)/SnO_(2)interface facilitates electron transfer from SnO_(2)to metallic Sn(S),generating a built-in electric field that stabilizes Sn^(4+)in SnO_(2)and accelerates proton-coupled electron transfer to*OCHO intermediates.Consequently,the catalyst achieves a formate Faradaic efficiency exceeding 90% over a broad potential window(-0.6 to -1.0 V vs.reversible hydrogen electrode(RHE))with a high partial current density of -280 mA·cm^(-2),surpassing most reported Sn-based catalysts.This work elucidates the structural dynamics and interfacial enhancement mechanisms of heterojunction catalysts,offering a rational design principle for advanced CO_(2)RR electrocatalysts.
基金the Knowledge Innovation Project of the Chinese Academy of Sciences(KZCX2-103) the Major State Basic Research Project of China(G2000077700).
文摘Chinese Neogene Rhinocerotidae has quite a complete record and its temporalrange is the Early Miocene to Late Pliocene. The samples include 25 species in 4 tribes of 2subfamilies. They are used as a foundation for the study of the evolution of the family and itsrelation to climatic changes. Taxonomic diversity, new records and extinctions are estimated foreach Chinese Neogene mammal faunal unit (NMU). The diversity of Chinese Rhinocerotidae variesnoticeably throughout the Neogene and is recognized within five stages: the Middle Miocene and LateMiocene are stages of high diversity and the Early Miocene, early Late Miocene and Pliocene arestages of low diversity. Rhinocerotid diversity and morphology are closely related to environmentalfactors and particularly sensitive to changes in ambient temperature and humidity. Theinterpretation of climatic variation reflected in the evolution of Rhinocerotidae correspondsprecisely with the conclusions drawn from other workers and provides new evidence for research onthe Neogene terrestrial ecosystem in China.
文摘The evolution of the inland lakes in arid and semi-arid zones is accorded with the climatic fluctuation. The humid climate is in harmony with the higher water level and greater lake water quantity budget while arid climate is in correspondence with the lower water level and little water budget. Based on the analysis of the lake fluctuation and lake budget change, with the aid of the data of geom’orphology, palynology, sedimentology and chronology, It is found that the climate experienced a warm and humid period during 7000-3500 yr. B. P. and showed a drying and warming trend in the last century in the Central Asia.
基金National Science and Technology support Project of the Extreme Meteorological Disasters Risk Regionalization and Impact ssessment,No.2007BAC29B05CMA project of Meteorological Disaster Assessment,No.20082012208
文摘Based on the sand dust storms data and climatic data in 12 meteorological stations around sand dust storm originating areas of the Taklimakan Desert, we analyzed the trends of the number of dust storm days from 1960 to 2005 as well as their correlations with temperature, precipitation, wind speed and the number of days with mean wind speed 〉 5 m/s. The results show that the frequency of dust storm events in the Taklimakan region decreased with the elapse of time. Except Ruoqiang and Minfeng, in the other 10 meteorological stations, the frequency of dust storm events reduces, and in 4 meteorological stations of Kuqa, Korla, Kalpin and Hotan, the frequency of dust storm events distinctly decreases. The temperature has an increasing trend, while the average wind speed and the number of days with mean wind speed ≥ 5 m/s have decreasing trends. The correlation analysis between the number of days of dust storms and climatic parameters demonstrates that wind speed and the number of days with mean wind speed 〉 5 m/s have strong positive correlation with the number of days of dust storms, with the correlations coefficients being 0.743 and 0.720 (p〈0.01), respectively, which indicates that strong wind is the direct factor resulting in sand dust storms. Whereas precipitation has significant negative correlation with the number of days of dust storms (p〈0.01), and the prior annual precipitation has also negative correlation, which indicates that the prior precipitation restrains the occurrence of sand dust storms, but this restraining action is weaker than the same year's precipitation. Temperature has negative correlation with the number of dust storm days, with a correlations coefficient of -0.433 (p〈0.01), which means that temperature change also has impacts on the occurrence of dust storm events in the Taklimakan region.
文摘The Qaidam Basin is. a tectonically controlled depression at 2700 m altitude on the northern margin of the Tibet Plateau. A succession of Neogene clastic sediments indicates lake depocentre migration from NW to SE. Towards late Pliocene, evaporative conditions developed with formation of gypsum, halite, celestite, mirabilite and bloedite. Continued deformation through Pleistocene developed a series of NW- SE trending domes and troughs. This setting continued to exert a controlling influence on basin and brine evolution and the progressive development of sulfate to chloride brines as, dry conditions intensified in late Pleistocene, at the end of which, extensive flat floors were formed in Dalangtan, Qarhan and other playas.The, model, which was set up based on the synthetic analyses, divides the fluctuating palaeoclimate since 750ka,B. P. into 11 warm and humid stages and 10 dry and cold stages. The water of the lakes evaporated during the dry-cold periods and were freshened during the warm-humid
基金GrantedbytheNationalNaturalScienceFoundationofChina (No .4 9972 0 5 7)
文摘In this paper, we make use of the functional spectral analysis to infer the periodicity of paleoclimate in the Hongzuisi section since about 15 ka. Through combined analysis of organic carbon isotope and CaCO\-3 content, the law of paleoclimatic evolution of the Hongzuisi section is obtained. There were climatic changes from 10 ka to about 0.1 ka over the last 15 ka. Among these cycles, the cycle of several ka is most remarkable. The result indicates that functional spectral analysis is helpful for paleoclimatic study, which can provide useful information about paleoclimatic reconstruction and future forecast.
基金founded by the Nationally Natural Science Foundation of China (41171159)the National Key Basic Research Program of China (2013CB956001)the Fundamental Research Funds for the Central Universities
文摘As the largest inland lake of China, along with its unique landscape and geographical location, Qinghai Lake has got much atten- tion of the scientists for a long time. The precursors have done substantive researches by using the lake sediment, which deepen our tmderstanding of the climate changes in this region. Although sand dunes and loess sediment are widely distributed around the lake, so far the researches on geochemical elements from aeolian sediment have been less reported. In this paper, we selected a typical aeolian profile on the east of Qinghai Lake. Based on systematic sampling and analysis of seven major geochemical ele- ments, combined with OSL dating and previous researches, this paper discusses climate changes in the Qinghai Lake area since 12.5 ka B.P.. Our conclusions are: (1) Before 12.5 ka B.P., the climate in this region was dry, cold, and accompanied by strong wind-sand activities. (2) During 12.5-11.9 ka B.P., the climate became warm and wet. However, there was an abrupt climate cooling event during 12.2-11.9 ka B.P., which likely corresponded to the Younger Dryas event. (3) During 11.9 8.0 ka B.P., the climate fluctuated greatly and frequently from warm to cold, and three cooling events occurred. (4) During 8.0-2.6 ka B.P., the climate was warm and humid. (5) Since 2.6 ka B.P., similar to the modem climate, the climate was mainly dry and cold.
文摘On the basis of lacustrine sedimentary profile of Ebinur Lake,sequences of evolution of paleoclimate and paleoenvironment in Ebinur Lake area have been rebuilt by analysing the sedimentary stratigraphy,bio-stratigraphy and gepochemistry as well as the chronological records.The results show that,during the last 10 ha years,the general change trends of the paleoclimate in Ebinur Lake area can be divided into three stages: (1) 10. 2-8.3 ka B. P., a warm-cool dry climate stage;(2) 8.3-3.5 ka B.P.,a warmer moist climate stage (specially,7.3-6. 4 ka B. P.,a relatively stable humid temperate stage);(3) 3. 5 ka B. P.-present, adraught temperate climate stage,similar to the present climate. In addition,there existed clearly several times of secondary undulations of dry-humid climate,i.e. 8.3 ka and 7.3 ka for dry climate
文摘Two hundred and thirty-five samples collected from Weinan loess section (L2 - S0)have analyzed by TOC (total organic carbon) and pyrolysis hydrocarbons. The curve of TOC with depth has ho set up and compared well with other climatic markers. The main periods of TOC variation of the last 0. 14 Ma are 67.08 ka and 18.29 ka, which is near with the periods of the variation of sunshine, showing that the TOC variation may be controlled by the variation of 65°N sunshine. The distribution of pyrolysis hydrocarbon and its parameters shows that there are two kinds of hydrocarbon associated with climatic change. One is called hydrocarbon pyrolysted directly from organism (pHC2-1) which is in the range of Tmax350℃ - 500℃, and associated with atmospheric water. The other is called carbonate inclusion inclusion (pHC2-2) which is in the range of Tmax 500℃ - 600℃ and formed by evaporation and associated with dry climate. The formula calculating humidity has been deduced Og = pHC2-1/(pHC2-1 + pHC2-2). The range of humidity of the section is 47% - 77% and the reducing is S1-3, S1-2, S0, S1-1, S1-4, S1-2, L1-1, L1-3, and L1-5. And the trend of the humidity is still increasing today.