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Current and further trajectories in designing functional materials for solid oxide electrochemical cells:A review of other reviews 被引量:2
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作者 Stanislav Baratov Elena Filonova +6 位作者 Anastasiya Ivanova Muhammad Bilal Hanif Muneeb Irshad Muhammad Zubair Khan Martin Motola Sajid Rauf Dmitry Medvedev 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期302-331,共30页
Complex oxides are an important class of materials with enormous potential for electrochemical appli-cations.Depending on their composition and structure,such complex oxides can exhibit either a single conductivity(ox... Complex oxides are an important class of materials with enormous potential for electrochemical appli-cations.Depending on their composition and structure,such complex oxides can exhibit either a single conductivity(oxygen-ionic or protonic,or n-type,or p-type electronic)or a combination thereof gener-ating distinct dual-conducting or even triple-conducting materials.These properties enable their use as diverse functional materials for solid oxide fuel cells,solid oxide electrolysis cells,permeable membranes,and gas sensors.The literature review shows that the field of solid oxide materials and related electro-chemical cells has a significant level of research engagement,with over 8,000 publications published since 2020.The manual analysis of such a large volume of material is challenging.However,by examining the review articles,it is possible to identify key patterns,recent achievements,prospects,and remaining obstacles.To perform such an analysis,the present article provides,for the first time,a comprehensive summary of previous review publications that have been published since 2020,with a special focus on solid oxide materials and electrochemical systems.Thus,this study provides an important reference for researchers specializing in the fields of solid state ionics,high-temperature electrochemistry,and energyconversiontechnologies. 展开更多
关键词 SOFCS SOECs PCFCS ELECTROCHEMISTRY Energy conversion Hydrogen energy Carbon neutrality
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Electrokinetic-mechanism of water and furfural oxidation on pulsed laser-interlaced Cu_(2)O and CoO on nickel foam 被引量:1
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作者 Yewon Oh Jayaraman Theerthagiri +3 位作者 M.L.Aruna Kumari Ahreum Min Cheol Joo Moon Myong Yong Choi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期145-154,共10页
The electrocatalytic oxidation of biomass-derived furfural(FF)feedstocks into 2-furoic acid(FA)holds immense industrial potential in optics,cosmetics,polymers,and food.Herein,we fabricated Co O/Ni O/nickel foam(NF)and... The electrocatalytic oxidation of biomass-derived furfural(FF)feedstocks into 2-furoic acid(FA)holds immense industrial potential in optics,cosmetics,polymers,and food.Herein,we fabricated Co O/Ni O/nickel foam(NF)and Cu_(2)O/Ni O/NF electrodes via in situ pulsed laser irradiation in liquids(PLIL)for the bifunctional electrocatalysis of oxygen evolution reaction(OER)and furfural oxidation reaction(FOR),respectively.Simultaneous oxidation of NF surface to NiO and deposition of CoO and/or Cu_(2)O on NF during PLIL offer distinct advantages for enhancing both the OER and FOR.CoO/NiO/NF electrocatalyst provides a consistently low overpotential of~359 m V(OER)at 10 m A/cm^(2),achieving the maximum FA yield(~16.37 m M)with 61.5%selectivity,79.5%carbon balance,and a remarkable Faradaic efficiency of~90.1%during 2 h of FOR at 1.43 V(vs.reversible hydrogen electrode).Mechanistic pathway via in situ electrochemical-Raman spectroscopy on CoO/NiO/NF reveals the involvement of phase transition intermediates(NiOOH and CoOOH)as surface-active centers during electrochemical oxidation.The carbonyl carbon in FF is attacked by hydroxyl groups to form unstable hydrates that subsequently undergo further oxidation to yield FA products.This method holds promise for large-scale applications,enabling simultaneous production of renewable building materials and fuel. 展开更多
关键词 Pulsed laser irradiation in liquids Water and furfural oxidation In situ Raman spectroscopy CoO/NiO/nickel foam Cu_(2)O/Nio/nickel foam 2-furoic acid
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A drone‑and feld‑based investigation of the land degradation and soil erosion at an opencast coal mine dump after 5 years’evolution of natural processes
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作者 Wu Xiao He Ren +3 位作者 Tao Sui Heyu Zhang Yanling Zhao Zhenqi Hu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第3期50-66,共17页
Opencast coal mining has a large impact on the land surface,both at the mining pits themselves and at waste sites.After artifcial management is stopped,a reclaimed opencast coal mine dump is afected by wind and water ... Opencast coal mining has a large impact on the land surface,both at the mining pits themselves and at waste sites.After artifcial management is stopped,a reclaimed opencast coal mine dump is afected by wind and water erosion from natural processes,resulting in land degradation and even safety incidents.In this paper,the soil erosion and land degradation after 5 years of such natural processes,at the Xilinhot opencast coal mine dump in Inner Mongolia,were investigated.A multisource data acquisition method was applied:the vegetation fraction coverage(VFC)was extracted from GF-1 satellite imagery,high-precision terrain characteristics and the location and degree of soil erosion were obtained using a drone,and the physical properties of the topsoil were obtained by feld sampling.On this basis,the degree and spatial distribution of erosion cracks were identifed,and the causes of soil erosion and land degradation were analyzed using the geographical detector.The results show that(1)multi-source data acquisition method can provide efective basic data for the quantitative evaluation of the ecological environment at dumps,and(2)slope aspect and VFC are the main factors afecting the degree of degradation and soil erosion.Based on above analysis,several countermeasures are proposed to mitigate land degradation:(1)The windward slope be designed to imitate the natural landform.(2)Reasonable engineering measures should be applied at the slope to restrain soil erosion.(3)The Pioneer plants should be widely planted on the platform at the early stage of reclamation. 展开更多
关键词 Coal mine dump Ecological restoration DRONE Soil erosion Ecosystem stability Geographical detector
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Pulsed laser interference patterning of transition-metal carbides for stable alkaline water electrolysis kinetics
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作者 Yewon Oh Jayaraman Theerthagiri +3 位作者 Ahreum Min Cheol Joo Moon Yiseul Yu Myong Yong Choi 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期65-80,共16页
We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed ... We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed laser ablation of Co,Fe,Ti,and Mo metals in acetone.The interaction between carbon s-p-orbitals and metal d-orbitals causes a redistribution of valence structure through charge transfer,leading to the formation of surface defects as observed by X-ray photoelectron spectroscopy.These defects influence the evolved TMCs,making them effective for hydrogen and oxygen evolution reactions(HER and OER)in an alkaline medium.Co_(3)C with more oxygen affinity promoted CoO(OH)intermediates,and the electrochemical surface oxidation to Co_(3)O_(4)was captured via in situ/operando electrochemical Raman probes,increasing the number of active sites for OER activity.MoC with more d-vacancies exhibits strong hydrogen binding,promoting HER kinetics,whereas Fe_(3)C and TiC with more defect states to trap charge carriers may hinder both OER and HER activities.The results show that the assembled membrane-less electrolyzer with Co_(3)C∥Co_(3)C and MoC∥MoC electrodes requires~2.01 and 1.99 V,respectively,to deliver a 10 mA cm−2 with excellent electrochemical and structural stability.In addition,the ascertained pulsed laser synthesis mechanism and unit-cell packing relations will open up sustainable pathways for obtaining highly stable electrocatalysts for electrolyzers. 展开更多
关键词 ACETONE H_(2)and O_(2)evolution reactions pulsed laser ablation surface defects transition-metal carbides water electrolyzer
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Assembly of low-voltage driven co-production of hydrogen and sulfur via Ru nanoclusters on metal-sulfur coordination:Insights from DFT calculations
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作者 Ahreum Min Velusamy Maheskumar +4 位作者 Dong Hyeon Lee Anuj Kumar Cheol Joo Moon Raja Arumugam Senthil Myong Yong Choi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期541-552,共12页
Herein,we propose a simple and rapid approach for synthesizing a CuS/Ru composite that serves as a bifunctional electrocatalyst to promote hydrogen production and concurrently convert sulfion into a value-added sulfur... Herein,we propose a simple and rapid approach for synthesizing a CuS/Ru composite that serves as a bifunctional electrocatalyst to promote hydrogen production and concurrently convert sulfion into a value-added sulfur product.This composite comprises Ru nanoclusters supported on the CuS nanostructure,achieved through simple pulsed laser irradiation in liquid approach.The optimized CuS/Ru-30 electrocatalyst demonstrates remarkable bifunctional electrocatalytic activity,exhibiting a negligible working potential of 0.28 V(vs.RHE)for the anodic sulfion oxidation reaction(SOR)and a minimal overpotential of 182 m V for cathodic hydrogen evolution reaction(HER)to achieve 10 mA cm^(-2)of current density.Moreover,the Cu S/Ru-30 electrocatalyst shows exceptional selectivity for converting sulfion into valuable sulfur during anodic oxidation reactions.Remarkably,in a two-electrode electrolyzer system utilizing Cu S/Ru-30 as both the anode and cathode,the SOR+HER coupled water electrolysis system demands only 0.52 V to reach 10 mA cm^(-2),which is considerably lesser compared to the OER+HER coupled water electrolysis(1.85 V).The experimental results and density function theory(DFT)calculations reveal that the strong electron interaction between CuS and Ru nanoclusters generates a built-in electric field,greatly enhancing electron transfer efficiency.This significantly boosts the HER performance and facilitates the adsorption and production of sulfur intermediates.This study presents a rapid and simple strategy for synthesizing a dual-functional catalyst suitable for low-voltage hydrogen generation while facilitating the recovery of valuable sulfur sources. 展开更多
关键词 Copper sulfide Ru nanoclusters Pulsed laser irradiation in liquids Sulfion oxidation reaction Hydrogen evolution reaction
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The surface electron transfer strategy promotes the hole of PDI release and enhances emerging organic pollutant degradation
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作者 Yunchuan Yang Dongyu Wang +2 位作者 Jisheng Geng Jun Liu Jun Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第10期84-91,共8页
In semiconductor photocatalysts,the easy recombination of photogenerated carriers seriously affects the application of photocatalytic materials in water treatment.To solve the serious problem of electron−hole pair rec... In semiconductor photocatalysts,the easy recombination of photogenerated carriers seriously affects the application of photocatalytic materials in water treatment.To solve the serious problem of electron−hole pair recombination in perylene diimide(PDI)organic semiconductors,we loaded ferric hydroxyl oxide(FeOOH)on PDI materials,successfully prepared novel FeOOH@PDI photocatalytic materials,and constructed a photo-Fenton system.The system was able to achieve highly efficient degradation of BPA under visible light,with a degradation rate of 0.112 min^(−1)that was 20 times higher than the PDI system,and it also showed universal degradation performances for a variety of emerging organic pollutants and anti-interference ability.The mechanism research revealed that the FeOOH has the electron trapping property,which can capture the photogenerated electrons on the surface of PDI,effectively reducing the compounding rate of photogenerated carriers of PDI and accelerating the iron cycling and H2O2 activation on the surface of FeOOH at the same time.This work provides new insights and methods for solving the problem of easy recombination of carriers in semiconductor photocatalysts and degrading emerging organic pollutants. 展开更多
关键词 perylene diimide organic semiconductors emerging pollutants surface electron transfer strategy PHOTO-FENTON
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Effect of Rare-Earth Element Substitution in Superconducting R_(3)Ni_(2)O_(7) under Pressure
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作者 Zhiming Pan Chen Lu +1 位作者 Fan Yang Congjun Wu 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期77-81,共5页
Recently,high temperature(T_(c)≈80 K)superconductivity(SC)has been discovered in La_(3)Ni_(2)O_(7)(LNO)under pressure.This raises the question of whether the superconducting transition temperature T_(c) could be furt... Recently,high temperature(T_(c)≈80 K)superconductivity(SC)has been discovered in La_(3)Ni_(2)O_(7)(LNO)under pressure.This raises the question of whether the superconducting transition temperature T_(c) could be further enhanced under suitable conditions.One possible route for achieving higher T_(c) is element substitution.Similar SC could appear in the Fmmm phase of rare-earth(RE)R_(3)Ni_(2)O_(7)(RNO,R=RE element)material series under suitable pressure.The electronic properties in the RNO materials are dominated by the Ni 3d orbitals in the bilayer NiO_(2) plane.In the strong coupling limit,the SC could be fully characterized by a bilayer single 3d_(x^(2)−y^(2))-orbital t–J‖–J⊥ model.With RE element substitution from La to other RE element,the lattice constant of the Fmmm RNO material decreases,and the resultant electronic hopping integral increases,leading to stronger superexchanges between the 3d_(x^(2)−y^(2)) orbitals.Based on the slave-boson mean-field theory,we explore the pairing nature and the evolution of T_(c) in RNO materials under pressure.Consequently,it is found that the element substitution does not alter the pairing nature,i.e.,the inter-layer s-wave pairing is always favored in the superconducting RNO under pressure.However,the T_(c) increases from La to Sm,and a nearly doubled T_(c) could be realized in SmNO under pressure.This work provides evidence for possible higher T_(c) R_(3)Ni_(2)O_(7) materials,which may be realized in further experiments. 展开更多
关键词 ELEMENT SUBSTITUTION RARE
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Magnetoresistance hysteresis in the superconducting state of kagome CsV_(3)Sb_(5)
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作者 Tian Le Jinjin Liu +1 位作者 Zhiwei Wang Xiao Lin 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期30-34,共5页
The hysteresis of magnetoresistance observed in superconductors is of great interest due to its potential connectionwith unconventional superconductivity.In this study,we perform electrical transport measurements on k... The hysteresis of magnetoresistance observed in superconductors is of great interest due to its potential connectionwith unconventional superconductivity.In this study,we perform electrical transport measurements on kagome superconductorCsV_(3)Sb_(5)nanoflakes and uncover unusual hysteretic behavior of magnetoresistance in the superconducting state.This hysteresis can be induced by applying either a large DC or AC current at temperatures(T)well below the superconductingtransition temperature(T_(c)).As T approaches T_(c),similar weak hysteresis is also detected by applying a smallcurrent.Various scenarios are discussed,with particular focus on the effects of vortex pinning and the presence of timereversal-symmtery-breaking superconducting domains.Our findings support the latter,hinting at chiral superconductivityin kagome superconductors. 展开更多
关键词 HYSTERESIS MAGNETORESISTANCE kagome superconductor chiral superconductor
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Poisonous Plants of the Karakalpak Part of the Ustyurt Plateau (Uzbekistan)
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作者 Aymuratov Rapat Abduraimov Ozodbek +2 位作者 Shomurodov Habibullo Abduraimov Azizbek Adilov Bekzod 《American Journal of Plant Sciences》 CAS 2024年第2期83-94,共12页
The article presents the composition and current state of poisonous plants distributed on the Ustyurt plateau. Ustyurt is one of the largest deserts in Central Asia, differing from other deserts of the world in geogra... The article presents the composition and current state of poisonous plants distributed on the Ustyurt plateau. Ustyurt is one of the largest deserts in Central Asia, differing from other deserts of the world in geographical location, relief, flora and fauna and other features. The territory of Ustyurt occupies 21.3 million hectares, of which the Karakalpak part accounts for 7.2 million hectares. Poisonous alkaloid-bearing plants of the Karakalpak part of the Ustyurt plateau Anabasis aphylla, Atriplex flabellum, Kalidium capsicum, Salsola arbusculaeformis, Salsola foliosa, Aellenia subaphylla, Anabasis brachiata, Rheum tataricum, Capparis spinosa, Glycyrrhiza aspera. Alkaloid-bearing plants that are not eaten or poorly eaten by cattle Ephedra distachya, Delphinium songaricum, Anabasis salsa, alkaloid-bearing plants eaten by animals without harm Carex physodes, Eremopyrum orientale, Agrophyllum repens, Astragalus amodendron, Astragalus villosissimus, species of the genera Calligonum, Salsola. Poisonous plants of the Karakalpak part of the Ustyurt plateau. An analysis of the pasture flora of the Karakalpak part of the Ustyurt plateau shows that 62 species of wild poisonous plants belonging to 49 genera and 19 families grow here. Although these plants are considered poisonous, but in modern pharmaceutics and medicine, they are used as medicinal. 展开更多
关键词 Ustyurt Plateau SPECIES Poisonous DESERT Climate Change
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The ALMA-QUARKS Survey.Ⅱ.The ACA 1.3 mm Continuum Source Catalog and the Assembly of Dense Gas in Massive Star-Forming Clumps
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作者 许峰玮 Ke Wang +30 位作者 Tie Liu Lei Zhu Guido Garay Xunchuan Liu Paul Goldsmith Qizhou Zhang Patricio Sanhueza Shengli Qin Jinhua He Mika Juvela Anandmayee Tej Hongli Liu Shanghuo Li Kaho Morii Siju Zhang Jianwen Zhou Amelia Stutz Neal JEvans Kee-Tae Kim Shengyuan Liu Diego Mardones Guangxing Li Leonardo Bronfman Ken’ichi Tatematsu Chang Won Lee Xing Lu Xiaofeng Mai Sihan Jiao James O.Chibueze Keyun Su Viktor L.Tóth 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期119-139,共21页
Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation... Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures”,is observing 139 massive starforming clumps at ALMA Band 6(λ~1.3 mm).This paper introduces the Atacama Compact Array(ACA)7 m data of the QUARKS survey,describing the ACA observations and data reduction.Combining multiwavelength data,we provide the first edition of QUARKS atlas,offering insights into the multiscale and multiphase interstellar medium in high-mass star formation.The ACA 1.3 mm catalog includes 207 continuum sources that are called ACA sources.Their gas kinetic temperatures are estimated using three formaldehyde transitions with a non-LTE radiation transfer model,and the mass and density are derived from a dust emission model.The ACA sources are massive(16–84 percentile values of 6–160 M_(⊙)),gravity-dominated(M∝R^(1.1))fragments within massive clumps,with supersonic turbulence(M>1)and embedded star-forming protoclusters.We find a linear correlation between the masses of the fragments and the massive clumps,with a ratio of 6%between the two.When considering fragments as representative of dense gas,the ratio indicates a dense gas fraction(DGF)of 6%,although with a wide scatter ranging from 1%to 10%.If we consider the QUARKS massive clumps to be what is observed at various scales,then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster formation.With the ACA data over four orders of magnitude of luminosity-to-mass ratio(L/M),we find that the DGF increases significantly with L/M,which indicates clump evolutionary stage.We observed a limited fragmentation at the subclump scale,which can be explained by a dynamic global collapse process. 展开更多
关键词 stars:formation ISM:kinematics and dynamics ISM:clouds stars:protostars
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Upward surface movement above deep coal mines after closure and flooding of underground workings 被引量:6
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作者 André Vervoort Pierre-Yves Declercq 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第1期53-59,共7页
After the mass closures of entire coal mine districts in Europe at the end of the last century, a new phenomenon of surface movement was observed—an upward movement.Although most surface movement(i.e., subsidence) oc... After the mass closures of entire coal mine districts in Europe at the end of the last century, a new phenomenon of surface movement was observed—an upward movement.Although most surface movement(i.e., subsidence) occurs in the months and years after mining by the longwall method, surface movement still occurs many decades after mining is terminated.After the closure and flooding of underground excavations and surrounding rock, this movement was reversed.This paper focuses on quantifying the upward movement in two neighboring coal mines(Winterslag and Zwartberg, Belgium).The study is based on data from a remote sensing technique: interferometry with synthetic aperture radar(INSAR).The results of the study show that the rate of upward movement in the decade after closure is about 10 mm/year on average.The upward movements are not linked directly to the past exploitation directly underneath a location.The amounts of subsidence at specific locations are linked mainly to their positions relative to an inverse trough shape situated over the entire mined-out areas and their immediate surroundings.Local features, such as geological faults, can have a secondary effect on the local variation of the uplift.The processes of subsidence and uplift are based on completely different mechanisms.Subsidence is initiated by a caving process, while the process of uplift is clearly linked to flooding. 展开更多
关键词 Coal mining Surface movement SUBSIDENCE UPLIFT Radar-interferometry
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A New Basal Neoceratopsian Dinosaur from the Middle Cretaceous of Jilin Province,China 被引量:7
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作者 JIN Liyong CHEN Jun +1 位作者 ZAN Shuqin Pascal GODEFROIT 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第2期200-206,共7页
A new basal neoceratopsian dinosaur, Helioceratops brachygnathus gen. et sp. nov., is described from the Quantou Formation (late Early Cretaceous or early Late Cretaceous) in the Liufangzi locality (Jilin province,... A new basal neoceratopsian dinosaur, Helioceratops brachygnathus gen. et sp. nov., is described from the Quantou Formation (late Early Cretaceous or early Late Cretaceous) in the Liufangzi locality (Jilin province, China). Helioceratops differs from other basal neoceratopsians with its deep dentary ramus, its steeply-inclined ventral predentary facet, its heterogeneous dentary crowns, and by the denticles and secondary ridges asymmetrically distributed on either side of the primary ridge on its dentary teeth. Along with Auroraceratops and Yamaceratops, Helioceratops represents one of the most derived non-coronosaurian neoceratopsians. The palaeogeographical distribution of basal neoceratopsians appears limited to northern China and southern Mongolia in the current state of our knowledge. It is therefore probable that this region constituted the birthplace for more advanced, Late Cretaceous Coronosanria. 展开更多
关键词 DINOSAURIA Neoceratopsia Middle Cretaceous Quantou Formation Jilin province
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The Global Boundary Stratotype Section and Point for the base of the Danian Stage (Paleocene, Paleogene,"Tertiary", Cenozoic) at El Kef, Tunisia—Original definition and revision 被引量:10
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作者 Eustoquio Molina Laia Alegret +7 位作者 Ignacio Arenillas José A. Arz Njoud Gallala Jan Hardenbol Katharina von Salis Etienne Steurbau Noeel Vandenberghe Dalila Zaghbib-Turki 《Episodes》 SCIE 2006年第4期263-273,共11页
The Cretaceous/Paleogene (K/Pg) Working Group, after many years of studies, voted to define the Global Stratotype Section and Point (GSSP) for the base of the Danian Stage at the base of the boundary clay at a sec... The Cretaceous/Paleogene (K/Pg) Working Group, after many years of studies, voted to define the Global Stratotype Section and Point (GSSP) for the base of the Danian Stage at the base of the boundary clay at a section near El Kef Tunisia. The GSSP was approved by the International Commission on Stratigraphy (ICS) and ratified by the International Union of Geological Sciences (IUGS) in 1991. Nevertheless, the GSSP was not officially published, although some papers dealing with geological aspects of the K/Pg boundary at El Kef have been published and this is quite well known. In April 2006, the GSSP was revisited, a marker was put in place and protection of the site was requested. Many correlation criteria are present at the GSSP of which the most useful are the meteorite impact evidence (iridium anomaly, Ni-rich spinel, etc.) and the mass extinction of planktic micro- and nannofossils. This event coincides with the GSSP, allowing us to propose that the K/Pg boundary is marked exactly by the moment of the meteorite impact, which implies that all the sediments generated by the impact belong to the Danian. This definition solves problems of correlation in the Yucatan peninsula (Mexico) and its surroundings. 展开更多
关键词 全球层型解剖面和点 古新世 第三纪 新生界 地质环境
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Nicotinamide overload may play a role in the development of type 2 diabetes 被引量:8
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作者 Shi-Sheng Zhou Da Li +19 位作者 Wu-Ping Sun Ming Guo Yong-Zhi Lun Yi-Ming Zhou Fu-Cheng Xiao Li-Xin Jing Shen-Xia Sun Li-Bin Zhang Ning Luo Fu-Ning Bian Wei Zou Lai-Bin Dong Zhi-Gang Zhao Sheng-Fan Li Xiao-Jie Gong Zeng-Guo Yu Chang-Bin Sun Cong-Long Zheng Dong-Ju Jiang Zheng-Ning Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第45期5674-5684,共11页
AIM: To investigate whether nicotinamide overload plays a role in type 2 diabetes. METHODS: Nicotinamide metabolic patterns of 14 diabetic and 14 non-diabetic subjects were compared using HPLC. Cumulative effects of... AIM: To investigate whether nicotinamide overload plays a role in type 2 diabetes. METHODS: Nicotinamide metabolic patterns of 14 diabetic and 14 non-diabetic subjects were compared using HPLC. Cumulative effects of nicotinamide and N^1-methylnicotinamide on glucose metabolism, plasma HzO2 levels and tissue nicotinamide adenine dinucleotide (NAD) contents of adult Sprague-Dawley rats were observed. The role of human sweat glands and rat skin in nicotinamide metabolism was investigated using sauna and burn injury, respectively. RESULTS: Diabetic subjects had significantly higher plasma N^1-methylnicotinamide levels 5 h after a 100-mg nicotinamide load than the non-diabetic subjects (0.89 ± 0.13 μmol/L vs 0.6 ± 0.13 μmol/L, P 〈 0.001). Cumulative doses of nicotinamide (2 g/kg) significantly increased rat plasma Nl-methylnicotinamide concentrations associated with severe insulin resistance, which was mimicked by Nl-methy-Inicotinamide. Moreover, cumulative exposure to N^1- methylnicotinamide (2 g/kg) markedly reduced rat muscle and liver NAD contents and erythrocyte NAD/ NADH ratio, and increased plasma H2O2 levels. Decrease in NAD/NADH ratio and increase in H2O2 generation were also observed in human erythrocytes after exposure to N^1-methylnicotinamide in vitro. Sweating eliminated excessive nicotinamide (5.3-fold increase in sweat nicotinamide concentration 1 h after a 100-mg nicotinamide load). Skin damage or aldehyde oxidase inhibition with tamoxifen or olanzapine, both being notorious for impairing glucose tolerance, delayed N^1- methylnicotinamide clearance. CONCLUSION: These findings suggest that nicotinamide overload, which induced an increase in plasma N^1- methylnicotinamide, associated with oxidative stress and insulin resistance, plays a role in type 2 diabetes. 展开更多
关键词 Type 2 diabetes NICOTINAMIDE N^1-methyl-nicotinamide Insulin resistance Oxidative stress Liver Sweat glands
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Pathological changes in the cellular structures of retina and choroidea in the early stages of alloxan-induced diabetes 被引量:6
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作者 Irina Danilova Svetlana Medvedeva +3 位作者 Svetlana Shmakova Margarita Chereshneva Alexey Sarapultsev Petr Sarapultsev 《World Journal of Diabetes》 SCIE CAS 2018年第12期239-251,共13页
AIM To investigate the temporal sequence of pathological changes in the cellular structures of retina and choroidea in the early stages of diabetes in laboratory animals.METHODS Experimental type 1 diabetes was modele... AIM To investigate the temporal sequence of pathological changes in the cellular structures of retina and choroidea in the early stages of diabetes in laboratory animals.METHODS Experimental type 1 diabetes was modeled by three intraperitoneal injections of an alloxan solution into 30 male nonlinear rats at 16 wk of age. The 30 th and 60 th days from the final alloxan injection were chosen as the endpoints. Light and electron microscopy and morphometric and immunohistochemical studies were performed on histological slices of eyeballs from experimental animals.RESULTS Diabetic disturbances progressed to 60 d of the experiment. Thus, in the retina, a partial destruction of photoreceptors accompanied by interstitial edema was observed. The morphometric analysis revealed a reduction in the thickness of the retina. A reduction in the number of blood vessels of the choroid with disturbances of the endothelial cells and the vascular walls and a persistent reduction in the number of melanocytes were observed. The number of proliferating Ki-67 positive cells decreased, and the number of macrophages increased with diabetes development.CONCLUSION The starting point in the development of destructive changes involves early reduction in the number of melanocytes of the choroidea and alterations in the retinal pigment epithelium. 展开更多
关键词 ALLOXAN DIABETES DIABETIC RETINOPATHY Early stage Morphology HISTOLOGICAL changes
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Female Reproductive Cycles of Phrynocephalus przewalskii (Lacertilia:Agamidae) in the Tengger Desert,China 被引量:3
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作者 Wei ZHAO Nannan YU +2 位作者 Yajuan WANG Weihong JI Naifa LIU 《Asian Herpetological Research》 SCIE 2011年第1期30-35,共6页
The timing of reproduction can significantly affect an offspring's fitness, thereby also influencing the fitness of the parents, especially in species inhabiting extreme environments, such as deserts. Female reproduc... The timing of reproduction can significantly affect an offspring's fitness, thereby also influencing the fitness of the parents, especially in species inhabiting extreme environments, such as deserts. Female reproductive cycles in Phrynocephalus przewalskii were studied from April to September 2008. Significant cycles of gonadal volume were found in all studied populations and the cycles were similar among the various populations. Females began vitellogenesis in April and contained oviductal eggs form May to June. Gonad volume decreased significantly in July and reached minimum volume from August to September. The follicular growth was negatively correlated with increasing precipitation and temperature in all populations. Hatching occurs during summer and early fall, when most of the annual rainfall occurs. Mean clutch size based on all populations was 2.7 ± 0.9 SE (n = 71). 展开更多
关键词 Phrynocephalus przewalskii LIZARD gonad cycle liver cycle clutch size Tengger Desert
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A Linear Frequency Principle Model to Understand the Absence of Overfitting in Neural Networks 被引量:2
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作者 Yaoyu Zhang Tao Luo +1 位作者 Zheng Ma Zhi-Qin John Xu 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第3期121-126,共6页
Why heavily parameterized neural networks(NNs) do not overfit the data is an important long standing open question. We propose a phenomenological model of the NN training to explain this non-overfitting puzzle. Our li... Why heavily parameterized neural networks(NNs) do not overfit the data is an important long standing open question. We propose a phenomenological model of the NN training to explain this non-overfitting puzzle. Our linear frequency principle(LFP) model accounts for a key dynamical feature of NNs: they learn low frequencies first, irrespective of microscopic details. Theory based on our LFP model shows that low frequency dominance of target functions is the key condition for the non-overfitting of NNs and is verified by experiments. Furthermore,through an ideal two-layer NN, we unravel how detailed microscopic NN training dynamics statistically gives rise to an LFP model with quantitative prediction power. 展开更多
关键词 networks NEURAL DETAILS
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Symmetry properties of fluctuations in an actively driven rotor 被引量:1
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作者 He Li Xiang Yang Hepeng Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期25-29,共5页
We investigate rotational dynamics of an actively driven rotor through experiments and numerical simulations. While probability density distributions of rotor angular velocity are strongly non-Gaussian, relative proba... We investigate rotational dynamics of an actively driven rotor through experiments and numerical simulations. While probability density distributions of rotor angular velocity are strongly non-Gaussian, relative probabilities of observing rotation in opposite directions are shown to be linearly related to the angular velocity magnitude. We construct a stochastic model to describe transitions between different states from rotor angular velocity data and use the stochastic model to show that symmetry properties in probability density distributions are related to the detailed fluctuation relation(FR) of entropy productions. 展开更多
关键词 Brownian motor active bath fluctuation relation active matter
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Fano Resonance Enabled Infrared Nano-Imaging of Local Strain in Bilayer Graphene 被引量:2
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作者 Jing Du Bosai Lyu +11 位作者 Wanfei Shan Jiajun Chen Xianliang Zho u Jingxu Xie Aolin Deng Cheng Hu Qi Liang Guibai Xie Xiaojun Li Weidong Luo Zhiwen Shi 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第5期60-66,共7页
Detection of local strain at the nanometer scale with high sensitivity remains challenging.Here we report near-field infrared nano-imaging of local strains in bilayer graphene by probing strain-induced shifts of phono... Detection of local strain at the nanometer scale with high sensitivity remains challenging.Here we report near-field infrared nano-imaging of local strains in bilayer graphene by probing strain-induced shifts of phonon frequency.As a non-polar crystal,intrinsic bilayer graphene possesses little infrared response at its transverse optical phonon frequency.The reported optical detection of local strain is enabled by applying a vertical electrical field that breaks the symmetry of the two graphene layers and introduces finite electrical dipole moment to graphene phonon.The activated phonon further interacts with continuum electronic transitions,and generates a strong Fano resonance.The resulted Fano resonance features a very sharp near-field infrared scattering peak,which leads to an extraordinary sensitivity of-0.002%for the strain detection.Our results demonstrate the first nano-scale near-field Fano resonance,provide a new way to probe local strains with high sensitivity in non-polar crystals,and open exciting possibilities for studying strain-induced rich phenomena. 展开更多
关键词 RED image Fano Resonance Enabled Infrared Nano-Imaging of Local Strain in Bilayer Graphene
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Room-temperature conversion of ethane and the mechanism understanding over single iron atoms confined in graphene 被引量:1
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作者 Suheng Wang Haobo Li +8 位作者 Mengqi He Xiaoju Cui Lei Hua Haiyang Li Jianping Xiao Liang Yu N.Pethan Rajan Zhaoxiong Xie Dehui Deng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第9期47-50,共4页
The catalytic conversion of ethane to high value-added chemicals is significantly important for utilization of hydrocarbon resources.However, it is a great challenge due to the typically required high temperature(>... The catalytic conversion of ethane to high value-added chemicals is significantly important for utilization of hydrocarbon resources.However, it is a great challenge due to the typically required high temperature(> 400 ℃) conditions.Herein, a highly active catalytic conversion process of ethane at room temperature(25 ℃) is reported on single iron atoms confined in graphene via the porphyrin-like N4-coordination structures.Combining with the operando time of flight mass spectrometer and density functional theory calculations, the reaction is identified as a radical mechanism, in which the C–H bonds of the same C atom are preferentially and sequentially activated, generating the value-added C2 chemicals, simultaneously avoiding the over-oxidation of the products to CO2.The in-situ formed O–FeN4–O structure at the single iron atom serves as the active center for the reaction and facilitates the formation of ethyl radicals.This work deepens the understanding of alkane C–H activation on the FeN4 center and provides the reference in development of efficient catalyst for selective oxidation of light alkane. 展开更多
关键词 ETHANE CONVERSION C–H activation GRAPHENE Single IRON atom Room-temperature reaction
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