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Chinese j.urnal of Aeronautics 2023年第5期36卷 33-40页

作者： j.rg SCHLÜter Dan ZHAO Abhishek SARKAR School of Engineering Deakin UniversityWaurn Ponds 3216Australia College of Engineering University of CanterburyChristchurch 8041New Zealand School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore

A better understanding of the mixing behavior of excited turbulent mixing layers is critical to a number of aerospace *** studies of excited turbulent mixing layers focused on single frequency excitation or the excitation with fundamental and its second harmonic *** is a lack of detailed studies on applying low and higher frequency *** this study,we have performed large-eddy simulations of periodically excited turbulent mixing *** excitation consists of a fundamental frequency and its third *** have used phase-averaging to identify the vortex structure and strength in the mixing layer,and we have studied the vortex *** different vortex paring mechanisms are observed depending on the phase shift between the two excitation *** influence of these two mechanisms on the mixing of a passive scalar is also *** is found that exciting the mixing layer with these low and high frequencies has initially an adverse influence on the mixing process;however,it improves the mixing further downstream of the splitter plate with the excitation using a phase shift ofΔφ=πshowing the best mixing *** present works shed lights on the fundamental vortex dynamics,and has great potential for aeronautical,automotive and combustion engineering applications.

关键词： Flow control Flow excitation Large eddy simulations Turbulent mixing layer Vortex dynamics

Deciphering Water Oxidation Catalysts: The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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NANO-MICRO LETterS 2025年第1期17卷 1-15页

作者： An, Li Li, j.anyi Sun, Yuanmiao Zhu, j.amin Seow, j.stin Zhu Yeow Zhang, Hong Zhang, Nan Xi, Pinxian Xu, Zhichuan j. Yan, Chun-Hua Lanzhou Univ Frontiers Sci Ctr Rare Isotopes Key Lab Nonferrous Met Chem & Resources Utilizat G State Key Lab Appl Organ ChemColl Chem & Chem Eng Lanzhou 730000 Peoples R China Nanyang Technol Univ Sch Mat Sci & Engn Singapore 639798 Singapore Chinese Acad Sci Fac Mat Sci & Energy Engn Shenzhen Inst Adv Technol Inst Technol Carbon Neutral Shenzhen 518055 Peoples R China Yunnan Univ Natl Ctr Int Res Photoelect & Energy Mat Electron Microscopy Ctr Sch Mat & EnergyKey Lab Electromagnet Mat & Devic Kunming 650091 Peoples R China Baotou Res Inst Rare Earths State Key Lab Baiyunobo Rare Earth Resource Res & Baotou 014030 Peoples R China Peking Univ Beijing Natl Lab Mol Sci State Key Lab Rare Earth Mat Chem & Applicat PKU HKU Joint Lab Rare Earth Mat & Bioinorgan Chem Beijing 100871 Peoples R China

Demonstrate that the key factor to determine the activity of reconstructed surfaces is the surface chemistry, instead of reconstruction degree using the popular perovskite LaNi1-xFexO3 oxides as model *** content can influence both the surface reconstruction degree, the activation degree, and the activity of reconstructed *** oxygen evolution reaction activity of reconstructed catalysts is primarily governed by the chemistry of the reconstructed surface species. Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction. The surface reconstruction has been widely observed in perovskite catalysts, and the reconstruction degree has been often correlated with the activity enhancement. Here, a systematic study on the roles of Fe substitution in activation of perovskite LaNiO3 is reported. The substituting Fe content influences both current change tendency and surface reconstruction degree. LaNi0.9Fe0.1O3 is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi1-xFexO3 (x = 0.00, 0.10, 0.25, 0.50, 0.75, 1.00) series. The reconstructed LaNi0.9Fe0.1O3 shows a higher intrinsic activity than most reported NiFe-based catalysts. Besides, density functional theory calculations reveal that Fe substitution can lower the O 2p level, which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability. Furthermore, it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree. The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction. This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

Scientometrics: untangling the topics

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National Science Review 2014年第3期1卷 343-345页

作者： ádám Szántó-Várnagy Péter Pollner Tamás Vicsek Illés j. Farkas Institute of Physics Eotvos University

Measuring science is based on comparing articles to similar ***,keyword-based groups of thematically similar articles are dominantly *** small sizes keep the statistical errors of comparisons *** the growing availability of bibliographic data,such statistical errors can be reduced by merging methods of thematic grouping,citation networks and keyword

关键词： untangling the topics Scientometrics APS ERC than

The nature of the companion of PSR j.719-1438: a white dwarf or an exotic obj.ct?

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Research in Astronomy and Astrophysics 2012年第7期12卷 813-816页

作者： j. E. Horvath Instituto de Astronomia Geofísica e Ciências Atmosfricas - Universidade de So Paulo

We raise the possibility that the very dense, compact companion of PSR j.719-1438, which has a j.piter-like mass, is an exotic quark obj.ct rather than a light helium or carbon white dwarf. The exotic hypothesis naturally explains some of the observed features, and provides quite strong predictions for this system, to be confirmed or refuted in feasible future studies.

关键词： binary pulsars -- exotic matter-- pulsars: individual (PSR j.719-1438)

Revealing the topological phase diagram of ZrTe_(5) using the complex strain fields of microbubbles

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npj.Computational Materials 2022年第1期8卷 1685-1691页

作者： Zoltán Taj.ov Dániel Nagy Konrád Kandrai j.nos Koltai LászlóOroszlány Péter Süle Zsolt EHorváth Péter Vancsó Levente Tapasztó Péter Nemes-Incze Centre for Energy Research Institute of Technical Physics and Materials Science1121BudapestHungary Department of Physics of Complex Systems ELTE Eötvös Loránd University1117BudapestHungary ELTE Eötvös Loránd University Department of Biological Physics1117BudapestHungary Budapest University of Technology and Economics 1111BudapestHungary

Topological materials host robust properties,unaffected by microscopic perturbations,owing to the global topological properties of the bulk electron *** in which the topological invariant can be changed by easily tuning external parameters are especially sought *** pentatelluride(ZrTe_(5))is one of a few experimentally available materials that reside close to the boundary of a topological phase transition,allowing the switching of its invariant by mechanical ***,we unambiguously identify a topological insulator–metal transition as a function of strain,by a combination of ab initio calculations and direct measurements of the local charge *** model quantitatively describes the response to complex strain patterns found in bubbles of few layer ZrTe_(5) without fitting parameters,reproducing the mechanical deformation-dependent closing of the band gap observed using scanning tunneling *** calculate the topological phase diagram of ZrTe_(5) and identify the phase at equilibrium,enabling the design of device architectures,which exploit the topological switching characteristics of the system.

关键词： density topological invariant

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher j.O’Connell Matthew j.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA j.mes L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain inj.ry(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

High temperature X-ray diffraction study of the formation of Na_(2)Ti_(3)O_(7) from a mixture of sodium carbonate and titanium oxide

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j.urnal of Energy Chemistry 2022年第2期31卷 210-218页

作者： Caroline Piffet Bénédicte Vertruyen Frédéric Hatert Rudi Cloots Frédéric Boschini Abdelfattah Mahmoud GREENMAT CESAM Research UnitChemistry DepartmentUniversity of Liège4000 LiègeBelgium Laboratory of Mineralogy Geology Research UnitUniversity of Liège4000 LiègeBelgium

Na2Ti3O7 has attracted much attention in the field of anode materials for Na-ion batteries thanks to its non-toxicity and very low working potential of 0.3 V vs Na0/Na+.Building a clearer picture of its formation from cheap Na_(2)CO_(3) and TiO_(2) starting materials is therefore of obvious ***,we report new insights from an in-situ high temperature X-ray diffraction study conducted from room temperature to 800°C,complemented by ex-situ *** were thereby able to position the previously reported Na_(4)Ti_(5)O_(12) and Na_(2)Ti_(6)O_(13) intermediate phases in a reaction scheme involving three successive steps and temperature *** and/or broadening of a subset of the Na_(2)Ti_(6)O_(13) reflections suggested a combination of intra-layer disorder with the well-established ordering of successive *** in-situ study was carried out on reproducible mixtures of Na_(2)CO_(3) and TiO_(2) in 1:3 molar ratio prepared by spraydrying of mixed aqueous ***-phase Na_(2)Ti_(3)O_(7) was obtained after only 8 h at 800°C in air,instead of a minimum of 20 h for a conventional solid-state route using the same *** analysis revealed~15 mm diameter granules made up from rectangular rods of a fewmm length presenting electrochemical properties in line with *** the absence of grinding or formation of intimate composites with conductive carbon,the specific capacity of 137 m Ah/g at C/5 decreased at higher rates.

关键词： Formation mechanism High temperature XRD Na_(2)Ti_(3)O_(7) Spray-drying synthesis Na-ion batteries

Formation of High-quality Advanced High-k Oxide Layers at Low Temperature by Excimer UV Lamp-assisted Photo-CVD and Sol-gel Processing

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Chemical Research in Chinese Universities 2004年第4期20卷 396-402页

作者： YU j. j. Electronic & Electrical Engineering University College London

We have successfully demonstrated that high quality and high dielectric constant layers can be fabricated by low temperature photo-induced or -assisted processing. Ta_2O_5 and ZrO_2 have been deposited at trical properties. Low leakage current densities on the order of 10 -8 A/cm 2 at 1 MV/cm for deposited ultrathin Ta_2O_5 films and ca.10 -6 A/cm 2 for the photo-CVD ZrO_2 layers and photo-irradiated sol-gel HfO_2 layers have been readily achieved. The improvement in the leakage properties of these layers is attributed to the UV-generated active oxygen species O( 1D) which strongly oxidize any suboxides to form more stoichiometric oxides on removing certain defects, oxygen vacancies and impurities present in the as-prepared layers. The photo-CVD Ta_2O_5 films deposited across 10.16-cm Si wafers exhibit a high thickness uniformity with a variation of less than \{±2.0%\} being obtained for ultrathin ca.10 nm thick films. The lamp technology can in principle be extended to larger area wafers, providing a promising low temperature route to the fabrication of a range of high quality thin films for future ULSI technology.

关键词： Excimer lamp High-kdielectrics Thin film Chemical vapour deposition(CVD) Sol-gel processing

Anisotropic modelling of Opalinus Clay behaviour: From triaxial tests to gallery excavation application

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j.urnal of Rock Mechanics and Geotechnical Engineering 2017年第3期9卷 53-66页

作者： Francois Bertrand Frédéric Collin Université de Liège Département ArGEnCo/Géomécanique Allée de la découverte 9 4000 Liège Belgium F.R.I.A Fonds de la Recherche Scientifique e FNRS Brussels Belgium

Deep repository in geological formations is the preferential solution considered in many countries to manage high-level nuclear wastes. In Switzerland, the Opalinus Clay is a candidate host rock. In this context, in situ and laboratory tests are conducted on Opalinus Clay to demonstrate the feasibility of deep disposal in this argillaceous formation. This paper presents a constitutive model able to fit the experimental data obtained from some triaxial tests conducted by j.hns(2013) on cores from borehole Schlattingen SLA-1. The elasto-plastic behaviour of Opalinus Clay is reproduced thanks to a DruckerPrager model, taking into account the anisotropy behaviour of this sedimentary rock. The obj.ctive is to employ a single set of parameters representative of the material. In a second version of the model, the stress-dependence of the elastic properties and damage are taken into account. Finally, the parameters calibrated with experimental tests are used to simulate the excavation of a gallery with a second gradient approach.

关键词： Opalinus Clay Schlattingen Constitutive modelling Anisotropy Dilatancy Localisation Tunnel excavation

Temporal dynamics of neonatal hypoxic-ischemic encephalopathy inj.ries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha j.Holdsworth Alistair j.Gunn Laura Bennet Hamid Abbasi Mātai Medical Research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy inj.ries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain inj.ry may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia