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journal of magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.j.Li j.H.Chu m.m.Li D.N.Zou L.B.Tong School of metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced Design and manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(Fg)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** Fg sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/Fg composite coating is 2131 times lower than that of bare mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the Fg sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of mg alloys.

关键词： mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

Evolution exploration and structure prediction of Keggin-type group IVB metal-oxo clusters

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Chinese Chemical Letters 2024年第5期35卷 487-492页

作者： Run-Han Li Tian-Yi Dang Wei guan jiang Liu ya-Qian Lan Zhong-min Su School of Chemistry South China Normal UniversityGuangzhou 510006China Institute of Functional material Chemistry Faculty of ChemistryNortheast Normal UniversityChangchun 130024China Institute of Theoretical Chemistry Jilin UniversityChangchun 130023China

The fascinating chemical structure and broad application prospect of Keggin-type polyoxometalates(POms)have attracted many chemists to explore and discover *** the traditional Keggin,larger metal atomic radius,higher metal coordinated numbers,lower metal valence states and other features allow the group IVB metal-based Keggin(IVB-Keggin)more space and unknown in terms of structure and ***,density functional theory(DFT)calculations were performed to explore the influences including cores,shells,caps,and terminal ligands,et *** IVB-Keggin,and analyze the possibility of novel structure *** the perspective of multi-layer onion-like clusters,molecular energy level,host-guest interaction energy,surface charge and covalent bond polarity can be further adjusted to achieve the oriented design of functional *** insights are expected to provide theoretical support for experimental synthesis,opening a new perspective to understand the growth of Keggin.

关键词： Keggin metal-oxo clusters group IVB Onion pattern DFT

Organic petrographic and mineralogical composition of the No. 6 coal seam of the Soutpansberg Coalfield, South Africa: Insights into paleovegetation and depositional environment

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International journal of Coal Science & Technology 2024年第3期11卷 190-207页

作者： Sanki Biswas Nicola j.Wagner Ofentse m.moroeng DSI-NRF CImERA/PPm Research group Department of GeologyUniversity of JohannesburgJohannesburgSouth Africa

This study investigates the paleodepositional conditions of the No.6 Seam of the madzaringwe Formation in makhado and Voorburg south area of the Soutpansberg Coalfield(Limpopo Province,South Africa)utilizing organic petrography and inorganic geochemical *** coals are predominantly high-volatile bituminous B-A rank with high ash yields(avg.36.1 wt%),characterized by high-vitrinite(~41.5 vol%),moderate-to-high inertinite(9.8 vol%–33.7 vol%)and low liptinite(~2.3 vol%).The distribution of inertinite varies among different coal horizons(from bottom-lower to middle-upper),suggesting differential oxidation conditions and/or paleofire ***-to-inertinite(V/I)ratio,tissue preservation–gelification index(TPI–gI),and groundwater–vegetation index(gWI–VI)plots,indicate that the peat-forming forest-swamp vegetation accumulated under mesotrophic-to-rheotrophic hydrological *** presence of structured macerals(i.e.,telinite,collotelinite,fusinite,and semifusinite)suggests well-preserved plant tissues,whereas framboidal pyrite and sulphur content(0.24 wt%–2.16 wt%)point to brackish-water influence at the peat *** coals contain quartz,kaolinite,siderite,muscovite,dolomite,calcite,and pyrite minerals,most of which were likely sourced from felsic igneous *** Al/(Al+Fe+mn)and(Fe+mn)/Ti ratios for the studied samples range between 0.24–0.97 and 0.57–70.10,*** ratios,Al–Fe–mn plot,and presence of massive botryoidal-type pyrite imply some influence of meteoric waters or fluids from hydrothermal activity ***,the chemical index of alteration(CIA:98.25–99.67),chemical index of weathering(CIW:92.04–97.66),and A–CN–K ternary diagram suggest inorganic matter suffered strong chemical weathering,indicating warm paleoclimatic conditions during the coal formation.

关键词： macerals Coal facies geochemical-indices Hydrothermal madzaringwe formation Soutpansberg Coalfield

Electroacupuncture activates AmPKa1 to improve learning and memory in the APP/PS1 mouse model of early Alzheimer's disease by regulating hippocampal mitochondrial dynamics

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journal of Integrative medicine 2024年第5期22卷 588-599页

作者： Wei-wei jia Hua-wei Lin min-guang yang ya-ling Dai yan-yi Ding Wen-shan Xu Si-nuo Wang ya-jun Cao Sheng-xiang Liang Zhi-fu Wang Cong Chen Wei-lin Liu College of Rehabilitation medicine Fujian University of Traditional Chinese Medicine The Institute of Rehabilitation Industry Fujian University of Traditional Chinese Medicine National-Local joint Engineering Research Center of Rehabilitation medicine Technology Fujian University of Traditional Chinese Medicine Traditional Chinese medicine Rehabilitation Research Center of State Administration of Traditional Chinese medicine Fujian University of Traditional Chinese Medicine

Objective: Studies have shown that electroacupuncture(EA) can alleviate cognitive impairments from Alzheimer's disease(AD) by regulating the expression of adenosine monophosphate-activated protein kinase(AmPK), but the specific mechanism involved remains to be elucidated. Therefore, this study explores the potential mechanism by which EA improves cognitive function from the perspective of mitochondrial ***: The four-month-old transgenic mice with amyloid precursor protein(APP)/presenilin 1(PS1)and AmPKa1-subunit conditional knockout(AmPKa1-cKO) were used for experiments. To evaluate the effects of EA treatment on cognitive function, the T-maze and morris water maze were used. In addition,chemical exchange saturation transfer, thioflavin staining, transmission electron microscopy, mitochondrial membrane potential, and Western blotting were used to examine the potential mechanisms underlying the effects of EA on APP/PS1 ***: Both APP/PS1 mice and AmPKa1-cKO mice exhibited dysfunction in mitochondrial dynamics accompanied by learning and memory impairment. Inactivation of the AmPK/peroxisome proliferatoractivated receptor-γ coactivator-1a(PgC-1a) pathway increased pathological amyloid-β(Aβ) deposition and aggravated the dysfunction in mitochondrial dynamics. In addition, EA rescued learning and memory deficits in APP/PS1 mice by activating the AmPK/PgC-1a pathway, specifically by reducing pathological Aβ deposition, normalizing energy metabolism, protecting the structure and function of mitochondria,increasing the levels of mitochondrial fusion proteins, and downregulating the expression of fission proteins. However, the therapeutic effect of EA on cognition in APP/PS1 mice was hindered by ***: The regulation of hippocampal mitochondrial dynamics and reduction in Aβ deposition via the AmPK/PgC-1a pathway are critical for the ability of EA to ameliorate cognitive impairment in APP/PS1 mice.

关键词： Adenosine monophosphate-activated protein kinase Alzheimer’s disease Cognitive impairment Electroacupuncture Hippocampus mitochondrial dynamics

The RFI Fast mitigation Algorithm Based on Block LmS Filter

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Research in Astronomy and Astrophysics 2024年第1期24卷 265-272页

作者： Han Wu Hai-Long Zhang ya-Zhou Zhang jie Wang Xu Du Ting Zhang Xin-Chen Ye Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China National Astronomical Data Center Beijing 100101China

The radio telescope possesses high sensitivity and strong signal collection *** receiving celestial radiation signals,it also captures Radio Frequency Interferences(RFIs)introduced by human ***,as signals originating from sources other than the astronomical targets,significantly impacts the quality of astronomical *** paper presents an RFI fast mitigation algorithm based on block Least mean Square(LmS)*** enhances the traditional adaptive LmS filter by grouping L adjacent time-sampled points into one block and applying the same filter coefficients for filtering within each *** transformation reduces multiplication calculations and enhances algorithm efficiency by leveraging the time-domain convolution *** algorithm is tested using baseband data from the Parkes 64 m radio telescope's pulsar observations and simulated *** results confirm the algorithm's effectiveness,as the pulsar profile after RFI mitigation closely matches the original pulsar profile.

关键词： methods:data analysis techniques:interferometric (stars:)pulsars:individual(j0437-4715)

Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía m.López Baptista K.Watanabe T.Taniguchi E.Diez j.E.Velázquez-Pérez Y.m.meziani j.m.Caridad j.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en Luz y materia Estructurada(LUmES) University of Salamanca37008 SalamancaSpain Research Center for Electronic and Optical materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(gFETs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6g wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate gFET *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： graphene THz Photodetector Field-effect transistor Plasmonic

A STABILITY RESULT FOR TRANSLATINgSPACELIKE gRAPHS IN LORENTZ mANIFOLDS

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Acta mathematica Scientia 2024年第2期44卷 474-483页

作者：高雅毛井吴传喜 Faculty of mathematics and Statistics Key Laboratory of Applied Mathematics of Hubei ProvinceHubei UniversityWuhan430062China

In this paper,we investigate spacelike graphs defined over a domain Ω⊂m^(n) in the Lorentz manifold m^(n)×ℝ with the metric−ds^(2)+σ,where m^(n) is a complete Riemannian n-manifold with the metricσ,Ωhas piecewise smooth boundary,and ℝ denotes the Euclidean *** prove an interesting stability result for translating spacelike graphs in m^(n)×ℝ under a conformal transformation.

关键词： mean curvature flow spacelike graphs translating spacelike graphs maximal spacelike graphs constant mean curvature Lorentz manifolds

Structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano materials Science 2024年第4期6卷 475-483页

作者： A.D.Veloso A.m.Ferraria A.m.Botelho do Rego A.S.Viana A.j.S.Fernandes A.j.Fielding R.A.Videira m.C.Oliveira CQ-VR and Chemistry Department University of Trás-os-Montes e Alto Douro BSIRg iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa Centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics Department University of AveiroCampus de Santiago Faculty of Science Pharmacy and Biomolecular SchoolLiverpool John Moores University REQUImTE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

Dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （m）.In parallel,alcohol and ether （epoxide） surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPR） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon Surface functionalization NmR XPS Hydrophilic carbon Paramagnetic

mechanical performance of 22Simn2TiB steel welded with lowtransformation- temperature filler wire and stainless steel filler wire

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journal of Iron and Steel Research International 2024年第4期31卷 967-981页

作者： Zi-dong Lin Kai-jie Song Zhen Sun Zi-qian Zhu Xue-feng Zhao Constantinos goulas Wei ya Xing-hua Yu School of materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China Department of Design Production and management Faculty of Engineering Technology.University of TwenteEnschede 7500 AETheNetherlands Rotterdam Additive manufacture Fieldlab(RAmLAB) Rotterdam 3089 JWTheNetherlands

TX-80 low-transformation-temperature(LTT)welding wire was used to replace the traditional ER 307Si welding wire to realize the connection of 22Simn2TiB armor steel in manual overlay *** previously existing issues,such as welding cracks,large welding deformation,and severe welding residual stress,were solved to ensure good strength and ductility *** particular,with the same welding conditions,TX-80 LTT wire eliminates welding *** reduces the welding deformation no matter the base pretreatment of pre-setting angle or no pre-setting *** comparison,it was found that the microstructure at the TX-80 weld is mainly composed of martensite and a small amount of retained *** contrast,the microstructure of the ER 307Si weld consists of a large amount of austenite and a small amount of skeleton-like *** variation trend of residual stress and microhardness from the weld to the base were investigated and compared with the mechanical properties of base *** TX-80 and the ER 307Si tensile samples elongation is 6.76%and 6.01%,while the ultimate tensile strengths are 877 and 667 mPa,*** average impact toughness at room temperature of the ER 307Si weld is 143.9 j/cm^(2),much higher than that of the TX-80 weld,which is only 36.7 j/cm^(2).The relationship between impact and tensile properties with microstructure species and distribution was *** addition,the fracture surface of the tensile and the impact samples was observed and *** dimples,fewer pores,larger radiation zone,and shear lips of TX-80 samples indicate better tensile ductility and worse impact toughness than those of ER 307Si weld.

关键词： Low-transformation-temperature material 22Simn2TiB steel Welding deformation Residual stress martensitic transformation mechanical property

Correcting Climate model Sea Surface Temperature Simulations with generative Adversarial Networks:Climatology,Interannual Variability,and Extremes

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Advances in Atmospheric Sciences 2024年第7期41卷 1299-1312页

作者： ya WANg gang HUANg Baoxiang PAN Pengfei LIN Niklas BOERS Weichen TAO Yutong CHEN BO LIU Haijie LI State Key Laboratory of Numerical modeling for Atmospheric Sciences and geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Laboratory for Regional Oceanography and Numerical modeling Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Earth System modelling School of Engineering and DesignTechnical University of MunichOttobrunn 85521Germany Potsdam Institute for Climate Impact Research Potsdam 14412Germany Department of mathematics and global Systems Institute University of ExeterExeter EX44QEUK CmA Earth System modeling and Prediction Centre(CEmC) Chinese Academy of Meteorological SciencesBeijing 100081China

Climate models are vital for understanding and projecting global climate change and its associated ***,these models suffer from biases that limit their accuracy in historical simulations and the trustworthiness of future *** these challenges requires addressing internal variability,hindering the direct alignment between model simulations and observations,and thwarting conventional supervised learning ***,we employ an unsupervised Cycle-consistent generative Adversarial Network(CyclegAN),to correct daily Sea Surface Temperature(SST)simulations from the Community Earth System model 2(CESm2).Our results reveal that the CyclegAN not only corrects climatological biases but also improves the simulation of major dynamic modes including the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole mode,as well as SST ***,it substantially corrects climatological SST biases,decreasing the globally averaged Root-mean-Square Error(RmSE)by 58%.Intriguingly,the CyclegAN effectively addresses the well-known excessive westward bias in ENSO SST anomalies,a common issue in climate models that traditional methods,like quantile mapping,struggle to ***,it substantially improves the simulation of SST extremes,raising the pattern correlation coefficient(PCC)from 0.56 to 0.88 and lowering the RmSE from 0.5 to *** enhancement is attributed to better representations of interannual,intraseasonal,and synoptic scales *** study offers a novel approach to correct global SST simulations and underscores its effectiveness across different time scales and primary dynamical modes.

关键词： generative adversarial networks model bias deep learning El Niño-Southern Oscillation marine heatwaves