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Controllable synthesis of biomimetic wood stem nanoporous high entropy oxides catalysts for oxygen evolution reaction

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Nano Research 2025年第1期18卷 107-117页

作者： Wei Wang Weiqi Wang Huihui Wang Xing Lu Jinwen Zhang Yunzhuo Lu School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China School of Intelligence and Electronic Engineering Dalian Neusoft University of InformationDalian 116023China Guangdong Key Laboratory of Materials and Equipment in Harsh Marine environment Guangzhou Maritime UniversityGuangzhou 510725China

Bubbles generated during the oxygen evolution reaction(OER)in water splitting readily adhere to the electrode surface,thereby impeding contact between the electrolyte and the active sites,thereby increasing the ***,it is imperative to elucidate the bubble release behavior and engineer electrodes that facilitate faster bubble *** this study,inspired by the wood stem of the Norway spruce,we synthesized a gradient nanoporous high-entropy oxide(GNP-HEO)electrode with a controllable pore *** GNP-HEO,featuring a well-controlled gradient in pore size,is achieved through a straightforward strategy combining selective laser melting with selective phase *** unique gradient nanoporous structure not only facilitates bubble release but also diminishes the bubble shielding effect in OER,thereby enhancing electrocatalytic *** affect interaction of Al,Co,Cr,Fe,and Ni,coupled with the gradient nanoporous structure,yields exceptional OER performance,evidenced by an overpotential of 250 mV at a current density of 50 mA/cm^(2) and a Tafel slope of 38.0 mV/dec in 1 M *** functional theory calculations confirm that the GNPHEO adheres to the adsorbate evolution mechanism reaction pathway and exhibits significant *** work highlights a promising approach for the design and synthesis of high-performance OER electrocatalysts.

关键词： oxygen evolution reaction high-entropy oxides selective phase dis-solution selective laser melting gradient nanoporous

Microphase separation of a miscible binary liquid mixture under confinement at the nanoscale

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npj Computational Materials 2019年第1期5卷 766-775页

作者： Ilham Essafri Denis Morineau Aziz Ghoufi Institut de Physique de Rennes IPRCNRS-Universitéde Rennes 1UMR CNRS 625135042 RennesFrance

Recent experimental works suggested that the confinement into a cylindrical nanopore induced the microphase separation of a binary liquid,despite the miscible character of its bulk counterpart.A core–shell organization was evidenced such that one of the liquids was strongly anchored to the solid surface whereas the other was confined at the center of the *** the same time,a study based on atomistic simulations suggested a strong heterogeneity and the absence of a *** this work,by refining the solid–liquid interactions to qualitatively reproduce the experimental adsorption isotherms of both single liquids,the microphase separation and the core–shell structure are *** tuning the surface chemistry of the nanopore to mimic hydrophilic and hydrophobic confinement,we show that it is possible to control the structural characteristics of the core–shell *** molecular origin of the microphase separation is then ascribed to the strong hydrogen bonds and a commensurate arrangement between the confining material and both liquids.

关键词： separation liquid binary

Animal personality and the ecological impacts of freshwater non-native species

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Current Zoology 2014年第3期60卷 417-427页

作者： Tristan JUETTE cnrs Universite Paul Sabatier ENFA umr 5174 EDB (Laboratoire Evolution & Diversite Biologique) Universite Toulouse 3 Paul Sabatier CNRS

While the ecological impacts of invasive species have been demonstrated for many taxonomic groups, the potential effects of behavioural variation among nonnative individuals （i.e. personality） on these impacts have been largely overlooked. This is despite the fact that recent studies have demonstrated that, by nature, the three first stages of biological invasions （i.e. transport, establishment and spread） can lead to personalitybiased populations. Freshwater ecosystems provide a unique oppor tunity to investigate this issue, notably because the ecological impacts of nonnative species have been extensively documented and because animal personality has been widely studied using freshwater model species. Here, we aim at developing some per spectives on the potential effects of animal personality on the ecological impacts of freshwater nonnative species across levels of biological organizations. At the individual level, personality types have been demonstrated to affect the physiolo gy, metabolism, life history traits and fitness of individuals. We used these effects to discuss how they could subsequently impact invaded popula tions and, in turn, recipient communities. We also discussed how these might translate into changes in the structure of food webs and the functioning of invaded ecosystems. Finally we discussed how these perspectives could interact with the management of invasive species .

关键词： Biological invasions Behavioural syndromes Aquatic ecosystems Temperaments Behavioural types Cascadingeffects

Biomimetic Autopilot Based on Minimalistic Motion Vision for Navigating along Corridors Comprising U-shaped and S-shaped Turns

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Journal of Bionic Engineering 2015年第1期12卷 47-60页

作者： Julien R. Serres Franck Ruffier Aix-Marseille UniversitY CNRS ISM UMR 7287 Biorobotics Lab 13288 Marseille Cedex 09 France

A bioinspired autopilot is presented, in which body saccadic and intersaceadic systems are combined. This autopilot en- ables a simulated hovercraft to travel along corridors comprising L-junctions, U-shaped and S-shaped turns, relying on mini- realistic motion vision cues alone without measuring its speed or distance from walls, in much the same way as flies and bees manage their flight in similar situations. The saccadic system responsible for avoiding frontal collisions triggers yawing body saccades with appropriately quantified angles based simply on a few local optic flow measurements, giving the angle of inci- dence with respect to a frontal wall. The simulated robot negotiates stiff bends by triggering body saccades to realign its tra- jectory, thus traveling parallel with the wall along a corridor comprising sharp turns. Direct comparison shows that the per- formance of this new body saccade-based autopilot closely resembles the behavior of a fly using similar body saccade strategy when flying along a corridor with an S-shaped turn, despite the huge differences in terms of the inertia.

关键词： optic flow collision avoidance body saccades insect flight biorobotics biomimetics

Late Quaternary clay minerals off Middle Vietnam in the western South China Sea: Implications for source analysis and East Asian monsoon evolution

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Science China Earth Sciences 2007年第11期50卷 1674-1684页

作者： Christophe COLIN Laboratoire IDES UMR 8148 CNRS Université de Paris XI Orsay 91405 France

High-resolution clay mineral records combined with oxygen isotopic stratigraphy over the past 450 ka during late Quaternary from Core MD05-2901 off Middle Vietnam in the western South China Sea are re-ported to reconstruct a history of East Asian monsoon evolution. Variations in Illite, chlorite, and kaolinite contents indicate a strong glacial-interglacial cyclicity, while changes in smectite content present a higher frequency cyclicity. The provenance analysis indicates a mixture of individual clay minerals from various sources surrounding the South China Sea. Smectite derived mainly from the Sunda shelf and its major source area of the Indonesian islands. Illite and chlorite originated mainly from the Mekong and Red rivers. Kaolinite was provided mainly by the Pearl River. Spectral analysis of the kaolin-ite/(illite+chlorite) ratio displays a strong eccentricity period of 100 ka, implying the ice sheet-forced win-ter monsoon evolution; whereas higher frequency changes in the smectite content show an ice sheet-forced obliquity period of 41 ka, and precession periods of 23 and 19 ka and a semi-precession period of 13 ka as well, implying the tropical-forced summer monsoon evolution. The winter monsoon evolution is generally in coherence with the glacial-interglacial cyclicity, with intensified winter monsoon winds during glacials and weakened winter monsoon winds during interglacials; whereas the summer monsoon evolution provides an almost linear response to the summer insolation of low latitude in the Northern Hemisphere, with strengthened summer monsoon during higher insolation and weakened summer monsoon during lower insolation. The result suggests that the high-latitude ice sheet and low-latitude tropical factor could drive the late Quaternary evolution of East Asian winter and summer monsoons, respectively, implying their diplex and self-contained forcing mechanism.

关键词： clay minerals,provenance,East Asian monsoon,late Quaternary,Middle Vietnam,South China Sea

Global significance of oxygen and carbon isotope compositions of pedogenic carbonates since the Cretaceous

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Geoscience Frontiers 2021年第4期12卷 34-45页

作者： Marc Jolivet Philippe Boulvais Géosciences Rennes CNRSUniv RennesUMR 6118F-35000RennesFrance

Few global syntheses of oxygen and carbon isotope composition of pedogenic carbonates have been attempted,unlike marine *** carbonates represent in-situ indicators of the climate conditions prevailing on *** δ^(18)O and δ^(13)C values of pedogenic carbonates are controlled by local and global factors,many of them not affecting the marine carbonates largely used to probe global climate *** compile pedogenic oxygen and carbon isotopic data(N=12,167)fromCretaceous to Quaternary-aged paleosols to identify potential trends through time and tie them to possible controlling *** discrete events such as the Paleocene-Eocene Thermal Maximum are clearly evidenced,our analysis reveals an increasing complexity in the distribution of the δ^(18)O vs δ^(13)C values through the *** could be expected,the rise of C4 plants induces a shift towards higherδ13C values during the Neogene and *** also show that the increase in global hypsometry during the Neogene plays a major role in controlling the δ^(18)O and δ^(13)C values of pedogenic carbonates by increasing aridity downwind of orographic ***,during the Quaternary,an increase of 3‰in δ^(18)O values is recorded both by the pedogenic carbonates and the marine foraminifera suggesting that both indicators may be used to track global climate signal.

关键词： Global isotopic signal Cretaceous–Quaternary Pedogenic carbonates Topography

The Moser-Trudinger-Onofri Inequality

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 777-802页

作者： Jean DOLBEAULT Maria J.ESTEBAN Gaspard JANKOWIAK Ceremade CNRS UMR 7534 and Université Paris-Dauphine Place de Lattre de Tassigny

This paper is devoted to results on the Moser-Trudinger-Onofri inequality, or the Onofri inequality for brevity. In dimension two this inequality plays a role similar to that of the Sobolev inequality in higher dimensions. After justifying this statement by recovering the Onofri inequality through various limiting procedures and after reviewing some known results, the authors state several elementary *** new results are also proved in this paper. A proof of the inequality is given by using mass transportation methods(in the radial case), consistently with similar results for Sobolev inequalities. The authors investigate how duality can be used to improve the Onofri inequality, in connection with the logarithmic Hardy-Littlewood-Sobolev *** the framework of fast diffusion equations, it is established that the inequality is an entropy-entropy production inequality, which provides an integral remainder term. Finally,a proof of the inequality based on rigidity methods is given and a related nonlinear flow is introduced.

关键词： Moser-Trudinger-Onofri inequality Duality Mass transportation Fast diffusion equation Rigidity

Quantitative Determination of Density of Ground State Atomic Oxygen from Both TALIF and Emission Spectroscopy in Hot Air Plasma Generated by Microwave Resonant Cavity

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Plasma Science and Technology 2016年第3期18卷 259-265页

作者： F.MARCHAL M.YOUSFI N.MERBAHI G.WATTIEAUX A.PIQUEMAL University of Toulouse UPSLAPLACE CNRS UMR 5213 CEA DAMDIF

Two experimental techniques have been used to quantify the atomic oxygen density in the case of hot air plasma generated by a microwave （MW） resonant cavity. The latter operates at a frequency of 2.45 GHz inside a cell of gas conditioning at a pressure of 600 mbar, an injected air flow of 12 L/min and an input MW power of 1 kW. The first technique is based on the standard two photon absorption laser induced fluorescence （TALIF） using xenon for calibration but applied for the first time in the present post discharge hot air plasma column having a temperature of about 4500 K near the axis of the nozzle. The second diagnostic technique is an actinometry method based on optical emission spectroscopy （OES）. In this case, we compared the spectra intensities of a specific atomic oxygen line （844 nm） and the closest wavelength xenon line （823 nm）. The two lines need to be collected under absolutely the same spectroscopic parameters. The xenon emission is due to the addition of a small proportion of xenon （1% Xe） of this chemically inert gas inside the air while a further small quantity of H2 （2~） is also added in the mixture in order to collect OH（A- X） and NH（A-X） spectra without noise. The latter molecular spectra are required to estimate gas and excitation temperatures. Optical emission spectroscopy measurements, at for instance the position z=12 mm on the axis plasma column that leads to a gas measured temperature equal to 3500 K, an excitation temperature of about 9500 K and an atomic oxygen density 2.09× 1017＋ 0.2×1017 cm-3. This is in very good agreement with the TALIF measurement, which is equal to 2.0×101T cm-3.

关键词： TALIF microwave air plasma atomic oxygen concentration actinometry,optical emission spectroscopy

Dynamics of a rigid body in a two-dimensional incompressible perfect fluid and the zero-radius limit Dedicated to Professor Jean-Yves Chemin on the Occasion of His 60th Birthday

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Science China Mathematics 2019年第6期62卷 1205-1218页

作者： Franck Sueur Institut de Mathématiques de Bordeaux CNRS UMR 5251 Université de Bordeaux

In this survey we report some recent results on the dynamics of a rigid body immersed in a twodimensional incompressible perfect fluid, with an emphasis on the zero-radius limit.

关键词： fluid-structure interaction point vortex perfect incompressible fluid