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Journal of Energy Chemistry 2024年第7期94卷 70-77页

作者： Haowen Cui Yan-Xia Chen Hefei National Research Center for physical Sciences at Microscale and department of Chemical Physics University of Science and Technology of ChinaHefei 230026AnhuiChina

Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte solution cannot be ***,we have systematically investigated the impact of adsorbate species and concentration,as well as solution pH,on the ORR activity on Pt(111)and Pt(poly)*** results all tend to establish a linear quantitative relationship between the onset potential for ORR and the adsorption equilibrium potential of the *** finding indicates the decisive role of adsorbates in the onset potential for ORR,suggesting that the adsorption potential of adsorbates can serve as an intuitive criterion for ORR *** support for this conclusion is derived from experimental results obtained from the oxygen evolution reaction on Pt(poly)with different adsorbate species and from the hydrogen evolution reaction on Pt(111)with iodine *** further propose both an empirical equation for the onset potential for ORR and the concept of a potential-regulated adsor-bate shielding effect to elucidate the influence of adsorbates on ORR *** study provides new insights into the high onset overpotential of the ORR and offers potential strategies for predicting and enhancingORRactivity inthefuture.

关键词： Oxygen reduction reaction Activity Adsorbate Equilibrium potential Pt(111)

Emission colour tuning in KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)phosphor

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Journal of Rare Earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri E Vijayatha V Ramasubramanian S Thiyagarajan P department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia department of Physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/Er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth Er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,Er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,Er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths Energy transfer upconversion Downshifting Colour coordinates

Dynamic kinetic stereodivergent transformations of propargylic ammonium salts via dual nickel and copper catalysis

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Chinese Chemical Letters 2024年第8期35卷 265-269页

作者： Ruilong Geng Lingzi Peng Chang Guo Hefei National Laboratory for physical Sciences at the Microscale and department of Chemistry University of Science and Technology of ChinaHefei 230026China

The dynamic kinetic asymmetric transformation of racemic propargylic ammonium salts with prochiral aldimine esters through a stereodivergent propargylation is catalyzed by dual nickel and copper ***,a diverse range of optically activeα-quaternary amino esters were produced via C-N bond cleavage with high reaction efficiency and stereoselectivity(up to>99%ee).By selection of the appropriate pair-wise combination of catalyst configurational isomers,all four possible stereoisomers of the corresponding propargylation products are obtained in high yields with excellent regio-,diastereo-,and enantioselectiv-ities.

关键词： Stereodivergent propargylation Dual catalysis C-N bond cleavage Azaomethine ylides Internal propargylic ammonium salts Excellent stereoselectivity

Advances in bio-inspired electrocatalysts for clean energy future

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Nano Research 2024年第2期17卷 515-533页

作者： Jing-Wen Duan Mu Min-Rui Gao Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Electrocatalysis can enable efficient energy storage and conversion and thus is an effective way to achieve carbon *** unique structure and function of organisms can offer many ideas for the design of electrocatalysts,which has become one of the most promising research ***,the understanding of the mechanism of bio-inspired electrocatalysis has become clearer,which has promoted the design of bio-inspired catalysts and catalytic *** bio-inspired catalysts(enzyme-like catalysts,layered porous catalysts,superhydrophobic/superhydrophilic surfaces,and so on)have been developed to enable efficient electrocatalytic ***,we discuss the key advances in the field of bio-inspired electrocatalysts progressed in recent ***,the role of bio-inspiration in increasing the intrinsic activity and number of active sites of catalysts is ***,the structure and mechanism of layered porous catalytic systems that mimic biological transport systems are comprehensively ***,the design of three-phase interfaces from micro-nanoscale to atomic scale is highlighted,including the wettability of the electrode surface and the transport system near the *** conclude the review by identifying challenges in bio-inspired electrocatalysts and providing insights into future prospects for the exciting research field.

关键词： bio-inspired electrocatalysts active sites layered porous structure three-phase interface

Trigonometric tension B-spline collocation approximations for time fractional Burgers’equation

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Journal of Ocean Engineering and Science 2024年第5期9卷 508-516页

作者： Brajesh Kumar Singh Mukesh Gupta School of physical and Decision Sciences Department of MathematicsBabasaheb Bhimrao Ambedkar University Lucknow 226025(UP)INDIA

This manuscript’s aim is to form and examine the numerical simulation of Caputo-time fractional nonlinear Burgers’equation via collocation approach with trigonometric tension B-splines as base ***,L 1 discretization formula is utilized for the time fractional derivative and after linearizing the nonlinear term,the trigonometric tension B-spline interpolants are utilized to get a system of simultaneous linear equations that are solved via Gauss elimination ***,numerical approximation at the desired time level is *** is demonstrated via von-Neumann approach that proposed scheme produces stable *** results of six different test examples having their analytical solutions are compared with the results in the literature to validate the accuracy and efficiency of the scheme.

关键词： Fractional Burgers’equation Trigonometric tension B-spline Collocation scheme Gauss elimination method

On asymptotic stability of the 3D Boussinesq equations without heat conduction

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Science China Mathematics 2024年第2期67卷 253-280页

作者： Lihua Dong Yongzhong Sun School of physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816China department of Mathematics Nanjing UniversityNanjing 210093China

We investigate the asymptotic stability of the solutions to Boussinesq equations without heat conduction with the initial data near a specific stationary solution in the three-dimensional domain Ω=R^(2)×(0,1).It is shown that the solution starting from a small perturbation to the stationary solution converges to it with explicit algebraic rates as time tends to infinity.

关键词： Boussinesq equations stationary solutions asymptotic stability decay rates

Quasinormal modes and ringdown waveforms of a Frolov black hole

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Communications in Theoretical Physics 2024年第10期76卷 101-107页

作者： Zhijun Song Huajie Gong Hai-Li Li Guoyang Fu Li-Gang Zhu Jian-Pin Wu Center for Gravitation and Cosmology College of Physical Science and Technology Yangzhou University Basic Teaching department Shenyang Institute of Engineering department of Physics and Astronomy Shanghai Jiao Tong University

In this paper we investigate scalar perturbation over a Frolov black hole（BH）, which is a regular BH induced by the quantum gravity effect. The quasinormal frequencies of a scalar field always consistently reside in the lower half-plane, and the time-domain evolution of the field demonstrates a decaying behavior, with the late-time tail exhibiting a power-law pattern. These observations collectively suggest the stability of a Frolov BH against scalar ***, our study reveals that the quantum gravity effect leads to slower decay modes. For the case of the angular quantum number l = 0, the oscillation exhibits non-monotonic behavior with the quantum gravity parameter α0. However, once l ≥ 1, the angular quantum number surpasses the influence of the quantum gravity effect.

关键词： black hole Frolov black hole quantum gravity effects quasinormal modes

Cyclohexanol optimizes Pt/ionomer interface in fuel cell cathodes

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Science China Chemistry 2024年第2期67卷 417-419页

作者： Lei Tong Hai-Wei Liang Hefei National Research Center for physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei230026China

This highlight is based on a recent article published in Nature Catalysis, in which Wei's group [1] from Chongqing University proposes a novel approach to enhance the performance of proton exchange membrane fuel cells(PEMFCs)by adjusting the interface between Pt and ionomer in the cathode catalyst layer. Their strategy involves adding cyclohexanol to the cathode catalyst ink to impede the adsorption of sulfonate groups from the ionomer onto Pt nanoparticles, which results in the release of Pt activity sites and a significant improvement in the mass transport efficiency.

关键词： interface catalyst adding

Chronic venous insufficiency, could it be one of the missing pieces in the puzzle of treating pain?

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World Journal of Clinical Cases 2024年第1期12卷 232-235页

作者： Min Cheol Chang department of physical Medicine and Rehabilitation Yeungnam University HospitalDaegu 705-717South Korea

Pain is a common complaint among patients seeking medical *** left un-treated,pain can become chronic,significantly affecting patients’quality of *** accurate diagnosis of the underlying cause of pain is crucial for effective *** venous insufficiency(CVI)is frequently overlooked by pain ***,many pain physicians lack sufficient knowledge about *** is a common condition resulting from malfunctioning or damaged valves in lower limb *** of CVI,ranging from mild to severe,include pain,heaviness,fatigue,itching,swelling,skin color changes,and ulcers in the lower ***,it has become more widely known that these symptoms can be attributed to *** slight or mild CVI can cause related *** physicians primarily consider neuromusculoskeletal disorders when assessing patients with leg pain,and often neglect the possibility of *** clinical practice,when pain physicians encounter patients with unresolved leg pain,they must assess whether the patients exhibit symptoms of CVI and conduct tests to differ-entiate CVI from other potential causes.

关键词： Pain Chronic venous insufficiency Diagnosis Treatment Vein

Effect of reaction and post-treatment conditions on physico-chemical properties of magnetic iron oxide nano-particles Author links open overlay panel

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Particuology 2024年第8期91卷 155-167页

作者： Masome Moeni Mohamed Edokali Matthew Rogers Oscar Cespedes Louey Tliba Tamseela Habib Robert Menzel Ali Hassanpour School of Chemical and Process Engineering Faculty of Engineering and Physical ScienceUniversity of LeedsLeedsLS29JTUK School of Physics and Astronomy Faculty of Engineering and Physical ScienceUniversity of LeedsLeedsLS29JTUK Mechanical Engineering department University of Engineering&TechnologyLahorePakistan School of Chemistry Faculty of Engineering and Physical ScienceUniversity of LeedsLeedsLS29JTUK

Poor stability and dispersibility,as well as aggregation are considered as major challenges in clinical application of iron oxide nanoparticles(IONPs).Several studies have shown that the synthesis parameters and post-synthesis treatments e.g.,drying methods,have the capability to improve the particles'***,we investigate the combined effect of synthesis and post-treatment parameters on the particle size,stability and magnetism of ***(Fe_(3)O_(4))NPs were prepared via co-precipitation and post-treated using different methods,i.e.(i)freeze dried at-53℃,0.133 mbar for 48 h(liquid nitrogen frozen(LFD)and freezer frozen(FFD)),(ii)vacuum oven dried(VOD)at 60℃for 24 h,and(iii)kept wet colloidal(WET),dispersed in deionized *** Fe_(3)O_(4)NPs’chemical functional groups,size,shape,crystallinity,stability,aggregation,porosity,and magnetic properties were further analysed using different characterisation *** results showed that,while the WET sample had the best stability and significantly less aggregation at different temperatures,amongst post-treated Fe_(3)O_(4)NPs,LFD sample exhibited the best stability(up to 37℃),dispersion and smallest polydispersity ***,all dried NPs had superparamagnetic characteristics,while,LFD Fe_(3)O_(4)NPs had better magnetic properties and stability than other drying methods.

关键词： Iron oxide nanoparticles Co-precipitation Stability Aggregation Magnetic properties