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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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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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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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Synergistic Oxygen Vacancy and Ru-N Coordination in RuO_(2)@NCC for Enhanced Acidic Oxygen Evolution Reaction
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作者 Mi Luo Linyao Huang +2 位作者 Chen Shen Tianhua Yang Chenguang Wang 《Carbon Energy》 2026年第1期115-125,共11页
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
关键词 OVSM-LOM oxygen evolution reaction oxygen vacancy Ru-N XAFS
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Ternary metal NiRuPt partition synergistic relay promotes pHuniversal hydrogen evolution
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作者 Miaoyang Yu Qiao Ye +7 位作者 Feng Wang Abdukader Abdukayum Nianpeng Li Lei Zhang Chuan Zuo Weiping Liu Xue Zhao Guangzhi Hu 《Nano Research》 2026年第1期244-252,共9页
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
关键词 hydrogen evolution reaction trimetallic nanohybrids synergistic catalysis seawater electrolysis
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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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Efficient oxygen evolution in acidic electrolysis of water using copper loaded with iridium nanoclusters
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作者 Yanan Song Bingxin Zhang +5 位作者 Tai Xiang Huabin Wang Yong Zhang Xiaoning Tang Lin Tian Rui Xu 《Journal of Environmental Sciences》 2026年第1期120-129,共10页
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
关键词 Heterostructure Oxygen evolution reaction(OER) ELECTROCATALYSIS Density functional theory(DFT)
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Advances in oxygen evolution reaction electrocatalysts via direct oxygen-oxygen coupling pathway:Recent progress,challenges,and perspectives
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作者 Xinying Yang Zhengda Chen +4 位作者 Guoxin Zhang Yuping Sun Jiangbo Lu Haiping Lin Xing Fan 《Nano Research》 2026年第1期23-49,共27页
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
关键词 oxygen evolution reaction *O-*O coupling mechanism dual-atom catalysts machine learning
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Microstructure evolution and corrosion behavior of refill friction stir spot welding joint for dissimilar Al alloys
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作者 Fang-yuan JIANG Da ZHANG +3 位作者 Yan-kun MA Jiang-tao XIONG Wei GUO Jing-long LI 《Transactions of Nonferrous Metals Society of China》 2026年第1期80-95,共16页
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
关键词 refill friction stir spot welding high strength Al alloy dissimilar joint microstructure evolution corrosion behavior
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Operando structural evolution of octahedral SnS_(2)/SnO_(2)heterojunctions enabling efficient CO_(2)-to-formate conversion over a broad potential window
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作者 Taojiang Deng Chengyu Qin +5 位作者 Liming Sun Li-Xia Liu Wenwen Zhan Guilin Zhuang Jingyi Jia Xiguang Han 《Nano Research》 2026年第1期224-232,共9页
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
关键词 CO_(2)reduction SnS_(2)/SnO_(2) heterojunction structure evolution reaction mechanisms
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The role of mergers and gas accretion in black hole growth and galaxy evolution 被引量:1
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作者 Tian-Chi Zhang Qi Guo +1 位作者 Yan Qu Liang Gao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第8期293-302,共10页
We use a semi-analytic galaxy formation model to study the co-evolution of supermassive black holes(SMBHs) with their host galaxies.Although the coalescence of SMBHs is not important,the quasarmode accretion induced b... We use a semi-analytic galaxy formation model to study the co-evolution of supermassive black holes(SMBHs) with their host galaxies.Although the coalescence of SMBHs is not important,the quasarmode accretion induced by mergers plays a dominant role in the growth of SMBHs.Mergers play a more important role in the growth of SMBH host galaxies than in the SMBH growth.It is the combined contribution from quasar mode accretion and mergers to the SMBH growth and the combined contribution from starburst and mergers to their host galaxy growth that determine the observed scaling relation between the SMBH masses and their host galaxy masses.We also find that mergers are more important in the growth of SMBH host galaxies compared to normal galaxies which share the same stellar mass range as the SMBH host galaxies. 展开更多
关键词 methods:numerical galaxies:evolution (galaxies:)quasars:supermassive black holes
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A Monte Carlo Study of the Evolution of the Scale Height of Normal Pulsars in the Galaxy 被引量:1
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作者 Ying-Chun Wei Xin-Ji Wu +2 位作者 Qiu-He Peng Na Wang Jin Zhang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第6期610-618,共9页
Based on the undisturbed, finite thickness disk gravitational potential, we carried out 3-D Monte Carlo simulations of normal pulsars. We find that their scale height evolves in a similar way for different velocity di... Based on the undisturbed, finite thickness disk gravitational potential, we carried out 3-D Monte Carlo simulations of normal pulsars. We find that their scale height evolves in a similar way for different velocity dispersions (δv): it first increases linearly with time, reaches a peak, then gradually decreases, and finally approaches a stable asymptotic value. The initial velocity dispersion has a very large influence on the scale height. The time evolution of the scale height is studied. When the magnetic decay age is used as the time variable, the observed scale height has a similar trend as the simulated results in the linear stage, from which we derive velocity dispersions in the range 70 - 178km s^-1, which are near the statistical result of 90 - 270km s^-1 for 92 pulsars with known transverse velocities. If the characteristic age is used as the time variable, then the observed and theoretical curves roughly agree for t 〉 10^8 yr only if av 〈 25km s^-1. 展开更多
关键词 pulsar general - stars evolution - galaxy structure - galaxy DISK
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GABE: Galaxy Assembly with Binary Evolution 被引量:1
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作者 Zhen Jiang Jie Wang +4 位作者 Liang Gao Feng-Hui Zhang Qi Guo Lan Wang Jun Pan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第10期121-137,共17页
We developed a new semi-analytic galaxy formation model: Galaxy Assembly with Binary Evolution(GABE). For the first time, we introduce binary evolution into semi-analytic models of galaxy formation by using the Yunnan... We developed a new semi-analytic galaxy formation model: Galaxy Assembly with Binary Evolution(GABE). For the first time, we introduce binary evolution into semi-analytic models of galaxy formation by using the Yunnan-Ⅱ stellar population synthesis model, which includes various binary interactions. When implementing our galaxy formation model onto the merger trees extracted from the Millennium simulation, it can reproduce a large body of observational results. We find that in the local universe, the model including binary evolution reduces the luminosity at optical and infrared wavelengths slightly, but it increases the luminosity at ultraviolet wavelengths significantly, especially in FUV band. The resulting luminosity function does not change very much over SDSS optical bands and infrared band, but the predicted colors are bluer, especially when the FUV band is under consideration. The new model allows us to explore the physics of various high energy events related to the remnants of binary stars, such as type Ia supernovae, short gamma-ray bursts and gravitational wave events, and their relation with host galaxies in a cosmological context. 展开更多
关键词 GALAXIES formation一galaxies LUMINOSITY function mass function-galaxies STELLAR content
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AGN Lifetimes in UV-selected Galaxies: A Clue to Supermassive Black Hole-galaxy Coevolution
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作者 Xiaozhi Lin Yongquan Xue +3 位作者 Guanwen Fang Lulu Fan Huynh Anh N Le Ashraf Ayubinia 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第1期104-113,共10页
The coevolution between supermassive black holes(SMBHs) and their host galaxies has been proposed for more than a decade,albeit with little direct evidence about black hole accretion activities regulating galaxy star ... The coevolution between supermassive black holes(SMBHs) and their host galaxies has been proposed for more than a decade,albeit with little direct evidence about black hole accretion activities regulating galaxy star formation at z> 1.In this paper,we study the lifetimes of X-ray active galactic nuclei(AGNs) in UV-selected red sequence(RS),blue cloud(BC) and green valley(GV) galaxies,finding that AGN accretion activities are most prominent in GV galaxies at z ~1.5-2,compared with RS and BC galaxies.We also compare AGN accretion timescales with typical color transition timescales of UV-selected galaxies.We find that the lifetime of GV galaxies at z~1.5-2 is very close to the typical timescale when the AGNs residing in them stay in the high-accretion-rate mode at these redshifts;for BC galaxies,the consistency between the color transition timescale and the black hole strong accretion lifetime is more likely to happen at lower redshifts(z <1).Our results support the scenario where AGN accretion activities govern UV color transitions of host galaxies,making galaxies and their central SMBHs coevolve with each other. 展开更多
关键词 galaxies:active galaxies:formation galaxies:evolution galaxies:high-redshift galaxies:nuclei (galaxies:)quasars:supermassive black holes galaxies:star formation galaxies:statistics
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The Origin of Cosmic Structures Part 3 — Supermassive Black Holes and Galaxy Cluster Evolution 被引量:1
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作者 J. C. Botke 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第2期345-371,共27页
In Part 1 of this work, we showed that our new model of cosmology can account for the origin of all cosmic structures ranging in size from stars up to superclusters. In this model, at the time of nucleosynthesis, an i... In Part 1 of this work, we showed that our new model of cosmology can account for the origin of all cosmic structures ranging in size from stars up to superclusters. In this model, at the time of nucleosynthesis, an imprint embedded in the vacuum regulated the creation of the protons (and electrons) that later made up the structures. Immediately after nucleosynthesis and for a considerable period afterward, the evolution was completely determined by the expansion of the universe. Gradually, however, gravitational influences became more important until finally, the expansion of the structures-to-be ceased at their zero velocity points. Stars, galaxies, and galaxy clusters all reached their zero velocity points more or less simultaneously at the usually accepted time of the beginning of galaxy formation. From that point onward, the evolution gravitation came to dominate the evolution although the expansion still exerted its influence. In this paper, we examine the subsequent cluster evolution in some detail. We establish the conditions required to prevent a free-fall collapse of the clusters and then show that galaxies with quasar-like active nuclei located within the cluster were the sources of the necessary radiation. We also show that the required galactic supermassive black holes were a consequence of the initial free-fall collapse of all galaxies. 展开更多
关键词 galaxy Cluster evolution Supermassive Black Holes Early Universe Time-Varying Curvature NUCLEOSYNTHESIS
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IRAS F21013-0739:a possible evolutionary successor of an ultraluminous infrared galaxy
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作者 Xian-Min Meng Hong Wu Chen Cao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第4期419-433,共15页
We present a stellar population synthesis study of a type II luminous infrared galaxy, IRAS F21013-0739. Optical images show clear characteristics of a merger remnant. The H-band absolute magnitude is MH = -25.1, whic... We present a stellar population synthesis study of a type II luminous infrared galaxy, IRAS F21013-0739. Optical images show clear characteristics of a merger remnant. The H-band absolute magnitude is MH = -25.1, which is -2 times as luminous as L* galaxies. Stellar populations are obtained through the stellar synthesis code STARLIGHT. We find that it experienced a recent starburst (SB) phase - 100 Myr ago. By reconstructing the ultraviolet-to-optical spectrum, and adopting Calzetti et al. and Leitherer et al.'s extinction curves, we estimate the past infrared (IR) luminosities of the host galaxy and find it may have experienced an ultraluminous infrared galaxy phase which lasted for about 100 Myr. Its i-band absolute magnitude is Mi = -22.463, and its spectral type shows type 2 active galactic nucleus (AGN) characteristics. The mass of the supermassive black-hole is estimated to be MBH = 1.6 × 107 M⊙ (lower- limit). The Eddington ratio Lbol/LEdd is 0.15, which is typical of Palomar-Green (PG) quasars. Both the nuclear SB and AGN contribute to the present IR luminosity budget, and the SB contributes -67%. On the diagram of IR color versus IR/opfical excess, it is located between IR quasars and PG quasars. These results indicate that IRAS F21013-0739 has probably evolved from a ULIRG, and it can possibly evolve into an AGN. 展开更多
关键词 INFRARED galaxies -- galaxies evolution -- galaxies starburst --galaxies: individual (IRAS F21013-0739) -- galaxies stellar content
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The Way to Quench:Galaxy Evolution in A2142
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作者 Cheng-Gong Qu Heng Yu +2 位作者 Antonaldo Diaferio Jubee Sohn DengQi Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期127-140,共14页
We show how the star formation activity of galaxies is progressively inhibited from the outer region to the center of the massive cluster A2142.From an extended spectroscopic redshift survey of 2239 galaxies covering ... We show how the star formation activity of galaxies is progressively inhibited from the outer region to the center of the massive cluster A2142.From an extended spectroscopic redshift survey of 2239 galaxies covering a circular area of radius~11 Mpc from the cluster center,we extract a sample of 333 galaxies with known stellar mass,star formation rate,and spectral index D_(n)4000.We use the Blooming Tree algorithm to identify the substructures of the cluster and separate the galaxy sample into substructure galaxies,halo galaxies,and outskirt galaxies.The substructure and halo galaxies are cluster members,whereas the outskirt galaxies are only weakly gravitationally bound to the cluster.For the cluster members,the star formation rate per stellar mass decreases with decreasing distance R from the cluster center.Similarly,the spectral index D_(n)4000 increases with R,indicating an increasing average age of the stellar population in galaxies closer to the cluster center.In addition,star formation in substructure galaxies is generally more active than in halo galaxies and less active than in outskirt galaxies,proving that substructures tend to slow down the transition between field galaxies and cluster galaxies.We finally show that most actively star-forming galaxies are within the cluster infall region,whereas most galaxies in the central region are quiescent. 展开更多
关键词 GALAXIES CLUSTERS individual(A2142)-galaxies star formation-galaxies evolution
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Galaxy Formation and Chemical Evolution
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作者 Sandeep Sahijpal 《International Journal of Astronomy and Astrophysics》 2014年第3期491-498,共8页
The manner the galaxy accretes matter, along with the star formation rates at different epochs, influences the evolution of the stable isotopic inventories of the galaxy. A detailed analysis is presented here to study... The manner the galaxy accretes matter, along with the star formation rates at different epochs, influences the evolution of the stable isotopic inventories of the galaxy. A detailed analysis is presented here to study the dependence of the galactic chemical evolution on the accretion scenario of the galaxy along with the star formation rate during the early accretionary phase of the galactic thick disk and thin disk. Our results indicate that a rapid early accretion of the galaxy during the formation of the galactic thick disk along with an enhanced star formation rate in the early stages of the galaxy accretion could explain the majority of the galactic chemical evolution trends of the major elements. Further, we corroborate the recent suggestions regarding the formation of a massive galactic thick disk rather than the earlier assumed low mass thick disk. 展开更多
关键词 GALACTIC Chemical evolution galaxy Formation SOLAR NEIGHBORHOOD SOLAR ELEMENTAL ABUNDANCES
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Evolutionary model of brain tumor circulating cells: Cellular galaxy 被引量:1
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作者 Parvin Mehdipour Firoozeh Javan +2 位作者 Morteza Faghih Jouibari Mehdi Khaleghi Masoud Mehrazin 《World Journal of Clinical Oncology》 CAS 2021年第1期13-30,共18页
BACKGROUND Although circulating tumor cells(CTCs)have been the focus of consideration for a decade,a categorized cell-based diagnostic strategy is unavailable.The personalized management and complementary/analytical-s... BACKGROUND Although circulating tumor cells(CTCs)have been the focus of consideration for a decade,a categorized cell-based diagnostic strategy is unavailable.The personalized management and complementary/analytical-strategy of data require an alphabetic guide.Therefore,we aimed to determine the behavior of CTCs in tumor and blood in order to provide the hypothetical-based agenda in the brain neoplasms.Exploring the protein expression(PE)using a single cell-based method would clarify the heterogeneity and diversity in tumor and blood,which are key events in the evolution in brain tumors.In fact,heterogeneity,diversity,and evolution are required for cancer initiation and progression.AIM To explore CTCs in brain tumors and blood cells and to assay intensity of PE through personalized insight.METHODS The focal population included 14 patients with meningioma,and four patients with metastatic brain tumors(T).PE was assayed by immunofluorescence in tumors cells and CTCs in 18 patients with brain tumors.Ratio test was applied between the T cells and CTCs in tumor tissue and in vascular system.T/CTC ratio-based classification of PE in macrophage chemoattractant chemokine ligand 2(CCL2),vascular endothelial growth factor(VEGF),epidermal growth factor(EGF),CD133,cyclin E,neurofilament marker,cytokeratin 19,and leukocyte common antigen(CD45)were investigated.RESULTS Total analyzed cells ranged between 10794-92283 for tumor cells and between 117-2870 for CTCs.Characteristics of histopathologic and status of an ataxiatelangiectasia mutated polymorphism(D1853N)in 18 patients affected with brain tumors were also provided.The course of evolution and metastatic event relied on the elevated protein expression in CTCs,which could be considered as a prognostic value.Diverse protein expression of the migrated cells into the blood stream and the tumor was indicative of the occurrence of evolution.Besides,the harmonic co-expression between CCL2/EGF and CCL2/VEGF could facilitate the tumor progression including the metastatic event.Expression of these proteins in the migrated vasculature and into the buccal tissue offered a non-invasive followup detection in neoplastic disorders.PE-exploration of neurofilament marker/CD133/VEGF of the CTCs in meningioma and cytokeratin 19/CD45/cyclin E in the patients with metastatic brain tumor would clarify the tumor biology of the brain neoplastic disorders.CONCLUSION The alphabetical base of the evolutionary mechanisms relies on dual-,triple-,and multi-models with diverse intensity of expression.In fact,cross-talk between initiative and the complementary channels defines the evolutionary insight in cancer.A diverse-model of protein expression,including low,medium,and high intensity,is the key requirement for the completed model.The cluster of cells with diverse expression and remarkable co-expression between CCL2/EGF/VEGF and NM/CD133/VEGF in CTCs may be indicative of probable invasiveness of the tumor.Furthermore,the mode of cytokeratin-19+/CD45-can be traced in the metastatic patients. 展开更多
关键词 Circulating tumor cells Brain tumor Protein expression PERSONALIZED Somatic/circulating tumor cell evolution METASTASIS
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Galaxy Evolution by the Incompatibility between Dark Matter and Baryonic Matter
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作者 Ding-Yu Chung 《International Journal of Astronomy and Astrophysics》 2014年第2期374-383,共10页
The paper derives the galaxy evolution by the non-interacting (incompatibility) between dark matter and baryonic matter in terms of the short-range separation between dark matter and baryonic matter, so dark matter ca... The paper derives the galaxy evolution by the non-interacting (incompatibility) between dark matter and baryonic matter in terms of the short-range separation between dark matter and baryonic matter, so dark matter cannot contact baryonic matter. In the conventional CDM (cold dark matter) model, dark matter and baryonic matter are interactive (compatible), so dark matter can contact baryonic matter. However, the conventional CDM model fails to account for the failure to detect dark matter by the contact (interaction) between dark matter and baryonic matter, the shortage of small galaxies, the abundance of spiral galaxies, the old age of large galaxies, and the formation of thin spiral galaxies. The non-interacting (incompatible cold dark matter) model can account for these observed phenomena. The five periods of baryonic structure development in the order of increasing non-interacting (incompatibility) are the free baryonic matter, the baryonic droplet, the galaxy, the cluster, and the supercluster periods. 展开更多
关键词 galaxy evolution CDM DARK MATTER MOND Baryonic MATTER INCOMPATIBLE DARK MATTER ICDM
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