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Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： Chen Chen Hongyu Xue Qilin Hu Mengfan Wang Pan Shang Ziyan Liu Tao Peng Deyang Zhang Yongsong Luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 46-51页

作者： Yiying Zhu Hesong Wang Anzhi Zhang School of Ecology and Nature Conservation Beijing Forestry UniversityBeijingChina Key Laboratory of Regional Climate and Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina college of Forestry and Landscape Architecture Xinjiang Agricultural UniversityUrumqiChina

Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability of *** the same time,detailed accounts of disturbances and forest responses are not yet well quantified in *** study employed the Breaks For Additive Seasonal and Trend method-an abrupt-change detection method-to analyze the Enhanced Vegetation Index time series in East Asia,South Asia,and Southeast *** approach allowed us to detect forest disturbance and quantify the resilience after *** showed that 20%of forests experienced disturbance with an increasing trend from 2000 to 2022,and Southeast Asian countries were more severely affected by ***,95%of forests had robust resilience and could recover from disturbance within a few *** resilience of forests suffering from greater magnitude of disturbance tended to be stronger than forests with lower disturbance *** summary,this study investigated the resilience of forests across the low and middle latitudes of Asia over the past two *** authors found that most forests exhibited good resilience after disturbance and about two-thirds had recovered to a better state in *** findings of this study underscore the complex relationship between disturbance and resilience,contributing to comprehension of forest resilience through satellite remote sensing.

关键词： Forest ecosystem Enhanced vegetation index Breaks for additive seasonal and trend method Disturbance Resilience

Efficient white-light-emitting lead-free halide double perovskites enabling full-spectrum pc-WLEDs

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Science China Materials 2025年第1期 305-306页

作者： Xiaoyong Huang college of physics and Optoelectronics Taiyuan University of Technology

With the rapid development of solid-state lighting, an important goal of phosphor-converted white light-emitting diodes (pc-WLEDs) is to provide a healthy and comfortable fullspectrum artificial light source with a co...

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A surface engineering strategy for the stabilization of zinc metal anodes with montmorillonite layers toward long-life rechargeable aqueous zinc ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 94-105页

作者： Wenbo Wang Ruifeng Xu Xu Zhang Peiyu Wang Bao Yang Bingjun Yang Juan Yang Kailimai Su Pengjun Ma Yanan Deng Xianfeng Fan Wanjun Chen Key Laboratory for Electronic Materials College of Electrical Engineering Northwest Minzu University Resource Chemistry and Energy Materials Research Center State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Institute for Materials and Processes School of Engineering University of Edinburgh

Rechargeable aqueous zinc-ion batteries （AZIBs） exhibit appreciable potential in the domain of electrochemical energy ***,there are serious challenges for AZIBs,for instance zinc dendrite growth,hydrogen evolution reaction （HER）,and corrosion side ***,we propose a surface engineering modification strategy for coating the montmorillonite （MMT） layer onto the surface of the Zn anode to tackle these issues,thereby achieving high cycling stability for rechargeable *** results reveal that the MMT layer on the surface of the Zn anode is able to provide ordered zincophilic channels for zinc ions migration,facilitating the reaction kinetics of zinc *** functional theory（DFT） calculations and water contact angle （CA） tests prove that MMT@Zn anode exhibits superior adsorption capacity for Zn2+and better hydrophobicity than the bare Zn anode,thereby achieving excellent cycling ***,the MMT@Zn||MMT@Zn symmetric cell holds the stable cycling over 5600 h at 0.5 mA cm-2and 0.125 m A h cm-2,even exceeding 1800 h long cycling under harsh conditions of 5 m A cm-2and 1.25 m A h *** MMT@Zn||V2O5full cell reaches over 3000 cycles at 2 A g-1with excellent rate ***,this surface engineering modification strategy for enhancing the electrochemical performance of AZIBs represents a promising application.

关键词： Surface engineering strategy Montmorillonite layer Protection mechanism of Zn anode Cycling stability Aqueous zinc ion batteries

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong Zhu Ruijie Liu Jiang Ma Lina Hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University college of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

Stability of the Fe12O12 cluster

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Nano Research 2018年第7期11卷 3574-3581页

作者： Xiaohu Yu Xuemei Zhang Xun-Wang Yan Institute of Theoretical and Computational Chemistry Shaanxi Key Laboratory of Catalysis School of Chemical & Environment Sciences Shaanxi University of Technology Hanzhong 723000 China Department of physics and Energetics Moscow Institute of Physics and Technology Dolgoprudny 141700 Russia college of physics and electricalengineering Anyang Normal University Anyang 455000 China

Superexchange effects play an important role in the determination of crystal structures; however, there has been much less reported on how they determine the stability of dusters. Using evolutionary search strategies and DFT＋U （density functional theory with the Hubbard U correction） calculations, we investigate the global minimum-energy structures of Fe12O12 clusters. Among predicted Fe12O12 dusters, a cage-shaped Fe12O12 cluster with unexpected stability was observed. In addition, the bare Fe12O12 cluster is shown to possess an extremely large energy gap （2.00 eV）, which is greater than that of C60, Au20 and Al13- clusters. Using a Heisenberg model, we traced the origin of the unexpected stability of the bare Fe12O12 cluster to magnetic competition between the nearestneighbor exchange constant h and the next-nearest neighbor exchange constant J2 that was induced by the superexchange interactions. The bare Fe12O12 cluster is thus a unique molecule that is stable and chemically inert.

关键词： Fe12O12 evolutionary program superexchange effect DFT+U Heisenberg model

Synthesis of porous CaO microsphere and its application in catalyzing transesterification reaction for biodiesel

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中国有色金属学会会刊：英文版 2009年第S3期19卷 674-677页

作者：白海鑫沈晓真刘小花刘圣勇 college of Sciences Henan Agricultural University college of Mechanical and electricalengineering Henan Agricultural University college of Mechanical and Electrical Engineering Henan AgriculturalUniversity college of Mechanical and Electrical Engineering Henan Agricultural University

It is hoped to develop a simple and low cost route for preparing the CaO with a novel morphology which can present high catalytic activity in catalyzing transesterification reaction for biodiesel. The porous CaO microsphere was synthesized by calcining spherical CaCO3 precursor which was prepared easily by mixing CaCl2 with Na2CO3. The as-prepared CaO microsphere was characterized by scanning electronic microscopy(SEM), powder X-ray diffractometry(XRD) and N2 adsorption experiment. The results reveal that the synthesized CaO is regular microsphere with many pores in its exterior and interior. The CaO microsphere is applied in catalyzing the transesterification reaction of soybean oil for biodiesel and presents excellent catalytic ability with a transesterification yield of 98.72%. This catalyst could have potential applications in other fields in view of its well-defined morphology, simply synthetic route and low cost.

关键词： porous CaO microsphere transesterification catalysis biodiesel

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan Ren Fei Zheng Tingwei Cao Qiang Wang International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina college of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2)forcing Key parameter Parameter estimation Data assimilation Machine learning

Synthesis and characterization of Ce_(0.8)Sm_(0.2–x)Pr_xO_(2–δ)(x=0.02–0.08)solid electrolyte materials

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Journal of Rare Earths 2015年第4期33卷 411-416页

作者：林晓敏吕秋月朱丽丽刘晓梅 college of physics Beihua University college of physics Jilin University

Solid electrolytes C%sSmo.2 xPrxO2-δ （x=0.02, 0.04, 0.06, 0.08） were prepared by citric-nitrate method. The microstructure and electrical properties of such materials were examined by X-ray diffraction （XRD）, atomic force microscopy （AFM）, Raman spec- troscopy （Raman）, X-ray photoelectron spectroscopy （XPS） and impedance spectroscopy analyses, Specifically, results from XRD analysis showed that samples calcined at 800 ℃ for 4 h possessed single-phase cubic fluorite structure, and the average grain size was found to be 36--45 nm. Further Raman spectral analysis indicated that oxygen vacancies should be present in the cubic fluorite struc- ture of ***0.08Oe~, and Pr-doping seemed to increase their concentration significantly. AFM images showed that the grain size grew with the increase of Pr substitution. XPS analysis confirmed the existence of oxygen vacancies in the lattice of ***2_~ in which Pr3＋ and Pr4＋ co-existed. AC impedance spectra indicated that the conductivity of ***0.2-xPrx02＋ increased with the increase of Pr-doping but the conduction activation energy decreased. Notably, it appeared that sample ***.12Pro.o802-x （aaoooc=l.21xlO-z S/cm, Ea=0.77 eV） exhibited conductivity superior to ***.2Ol.9 （aro0.c=2.22×10-3 S/cm, Ea= 1.02 eV） because it possessed higher conductivity and lower activation energy. At 600 ℃, the conductivity of ***.12Pr0.0802m was 4.45 times higher than that of the un-doped material.

关键词： Ce0.8Smo.2-xPrx02-δ oxygen vacancy Raman spectroscopy conductivity rare earths