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Simultaneous lidar observations of the sporadic Ni layer and sporadic Na layer in the MLT
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作者 ZhiJun Zhao XuYang Jiang +3 位作者 FuJu Wu YuHang Qi Jing Jiao GuoTao Yang 《Earth and Planetary Physics》 2026年第1期156-166,共11页
Here we report on simultaneous lidar observations of sporadic Ni(Nis)layers and sporadic Na(Nas)layers in the atmosphere over Yanqing,Beijing(40.42°N,116.02°E)from April 2019 to October 2022.During 343 night... Here we report on simultaneous lidar observations of sporadic Ni(Nis)layers and sporadic Na(Nas)layers in the atmosphere over Yanqing,Beijing(40.42°N,116.02°E)from April 2019 to October 2022.During 343 nights of observation,68 Nis and 56 Nas were observed.The seasonal variation of Nis and Nas was also obtained,with the highest occurrence of Nis being in July(43%)and that of Nas being in June(61%).We found that the seasonal variation of Nis is similar to that of Nas and that both occur more frequently in summer than in winter.In addition,we found 23 events in which Nis and Nas occur simultaneously.The average peak altitude of Nas is approximately 1 km higher than that of Nis,and the peak density ratio of Nas to Nis is approximately 5,which is half the density ratio of the two main layers.Additionally,the strength factor for Nas is smaller than that for Nis.Through data analysis of sporadic E layers(Es),we found that Nis and Nas has a significant correlation with Es.The neutralization rates of Ni^(+)/Na^(+)were calculated according to the dissociative recombination reaction of Ni^(+)/Na^(+)and the WACCM-Ni(Whole Atmosphere Community Climate Model of Ni).The production rates of Ni and Na were estimated to be approximately 1:4.4,which is consistent with the density ratio of Nis to Nas.The results showed that the neutralization reaction of Ni+,Na+,and electrons in Es is the main reason for the formation of the Nis layer and the Nas layer. 展开更多
关键词 lidar observation sporadic Ni layer sporadic Na layer sporadic E layer seasonal variation
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Latent and sensible heat fluxes in a very unstable atmospheric surface layer and weak-wind conditions in a tropical coastal ocean
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作者 Haitem M Almdhun Yusri Yusup +3 位作者 Ehsan Jolous Jamshidi Abdulghani Swesi Muhammad Fikri Sigid Abigail Adomako 《Atmospheric and Oceanic Science Letters》 2026年第1期47-52,共6页
The atmospheric surface layer of the tropical coastal ocean is commonly very unstable and experiences weakwind conditions.How the latent(LE)and sensible(H)heat fluxes behave under such conditions are unclear because o... The atmospheric surface layer of the tropical coastal ocean is commonly very unstable and experiences weakwind conditions.How the latent(LE)and sensible(H)heat fluxes behave under such conditions are unclear because of the lack of observation stations in the tropics.Thus,this study aims to analyze LE and H and the microclimate parameters influencing them.The authors deployed an eddy covariance system in a tropical coastal region for seven months.The microclimate parameters investigated were wind speed(U),vapor pressure deficit(Δe),temperature difference(ΔT),wind-vapor pressure deficit(UΔe),wind-temperature difference(UΔT),and atmospheric stability(z/L),where z is height and L is the Monin–Obukhov length.On the daily time scale,the results show that LE was more associated with U thanΔe,while H was more related toΔT than U.Cross-wavelet analysis revealed the strong coherence in the LE-U relationship for periods between one and two days,and for H–ΔT,0.5 to 1 day.Correlation and regression analyses confirmed the time series analyses results,where strong positive correlation coefficients(r)were obtained between LE and U(r=0.494)and H andΔT(r=0.365).Compared to other water bodies,the transfer coefficient of moisture(CE N)was found to be small(=0.40×10^(-3))and independent of stability;conversely,the transfer coefficient of heat(CH N)was closer to literature values(=1.00×10^(-3))and a function of stability. 展开更多
关键词 Latent heat Sensible heat Atmospheric surface layer Tropical coastal sea
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Multiscale Theoretical Calculations Empower Robust Electric Double Layer Toward Highly Reversible Zinc Anode
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作者 Yufan Xia Zhen Luo +6 位作者 Shuang Chen Yang Xiang Gao Weng Hongge Pan Ben Bin Xu Mi Yan Yinzhu Jiang 《Nano-Micro Letters》 2026年第3期406-427,共22页
The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter per... The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter persistent dendrite growth and parasitic reactions,driven by the inhomogeneous charge distribution and water-dominated environment within the EDL.Compounding this,classical EDL theory,rooted in meanfield approximations,further fails to resolve molecular-scale interfacial dynamics under battery-operating conditions,limiting mechanistic insights.Herein,we established a multiscale theoretical calculation framework from single molecular characteristics to interfacial ion distribution,revealing the EDL’s structure and interactions between different ions and molecules,which helps us understand the parasitic processes in depth.Simulations demonstrate that water dipole and sulfate ion adsorption at the inner Helmholtz plane drives severe hydrogen evolution and by-product formation.Guided by these insights,we engineered a“water-poor and anion-expelled”EDL using 4,1’,6’-trichlorogalactosucrose(TGS)as an electrolyte additive.As a result,Zn||Zn symmetric cells with TGS exhibited stable cycling for over 4700 h under a current density of 1 mA cm^(−2),while NaV_(3)O_(8)·1.5H_(2)O-based full cells kept 90.4%of the initial specific capacity after 800 cycles at 5 A g^(−1).This work highlights the power of multiscale theoretical frameworks to unravel EDL complexities and guide high-performance ARZB design through integrated theory-experiment approaches. 展开更多
关键词 Zn anode Theoretical calculations Electric double layers Aqueous rechargeable zinc batteries
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Typhoon Kompasu(2118)simulation with planetary boundary layer and cloud physics parameterization improvements
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作者 Xiaowei Tan Zhiqiu Gao Yubin Li 《Atmospheric and Oceanic Science Letters》 2026年第1期41-46,共6页
This study introduces a new ocean surface friction velocity scheme and a modified Thompson cloud microphysics parameterization scheme into the CMA-TYM model.The impact of these two parameterization schemes on the pred... This study introduces a new ocean surface friction velocity scheme and a modified Thompson cloud microphysics parameterization scheme into the CMA-TYM model.The impact of these two parameterization schemes on the prediction of the movement track and intensity of Typhoon Kompasu in 2021 is examined.Additionally,the possible reasons for their effects on tropical cyclone(TC)intensity prediction are analyzed.Statistical results show that both parameterization schemes improve the predictions of Typhoon Kompasu’s track and intensity.The influence on track prediction becomes evident after 60 h of model integration,while the significant positive impact on intensity prediction is observed after 66 h.Further analysis reveals that these two schemes affect the timing and magnitude of extreme TC intensity values by influencing the evolution of the TC’s warm-core structure. 展开更多
关键词 Tropical cyclone Numerical simulation Planetary boundary layer parameterization SCHEME Cloud physics scheme
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Regulation Engineering of Alkali Metal Interlayer Pillar in P2‑Type Cathode for Ultra‑High Rate and Long‑Term Cycling Sodium‑Ion Batteries
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作者 Xu Wang Zixiang Yang +7 位作者 Yujia Cai Heng Ma Jinglei Xu Rabia Khatoon Zhizhen Ye Dashuai Wang Muhammad Tariq Sajjad Jianguo Lu 《Nano-Micro Letters》 2026年第3期876-892,共17页
Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challeng... Layered oxides have attracted significant attention as cathodes for sodium-ion batteries(SIBs)due to their compositional versatility and tuneable electrochemical performance.However,these materials still face challenges such as structural phase transitions,Na^(+)/vacancy ordering,and Jahn–Teller distortion effect,resulting in severe capacity decay and sluggish ion kinetics.We develop a novel Cu/Y dual-doping strategy that leads to the formation of"Na–Y"interlayer aggregates,which act as structural pillars within alkali metal layers,enhancing structural stability and disrupting the ordered arrangement of Na^(+)/vacancies.This disruption leads to a unique coexistence of ordered and disordered Na^(+)/vacancy states with near-zero strain,which significantly improves Na^(+)diffusion kinetics.This structural innovation not only mitigates the unfavorable P2–O2 phase transition but also facilitates rapid ion transport.As a result,the doped material demonstrates exceptional electrochemical performance,including an ultra-long cycle life of 3000 cycles at 10 C and an outstanding high-rate capability of~70 mAh g^(−1)at 50 C.The discovery of this novel interlayer pillar,along with its role in modulating Na^(+)/vacancy arrangements,provides a fresh perspective on engineering layered oxides.It opens up promising new pathways for the structural design of advanced cathode materials toward efficient,stable,and high-rate SIBs. 展开更多
关键词 Sodium-ion batteries layered oxides P2-type phase Dual-site doping Regulation engineering
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Advancing layered double hydroxides (LDHs) as the anodes for efficient anion-exchange-membrane water electrolyzers
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作者 Dan Pan Tingting Zhai +3 位作者 Ran Zhang Yongjuan Yuan Hao Wang Siyu Lu 《Nano Research》 2026年第1期115-139,共25页
The transition to sustainable energy systems necessitates efficient hydrogen production via water electrolysis,with anion-exchange membrane water electrolyzers(AEMWEs)emerging as a cost-effective alternative by combin... The transition to sustainable energy systems necessitates efficient hydrogen production via water electrolysis,with anion-exchange membrane water electrolyzers(AEMWEs)emerging as a cost-effective alternative by combining the merits of alkaline water electrolyzers(AWEs)and proton-exchange membrane water electrolyzers(PEMWEs).However,challenges persist in membrane stability,oxygen evolution reaction(OER)kinetics,and mass transport efficiency.This review highlights the pivotal role of transition metal-based layered double hydroxides(LDHs)as high-performance,non-precious OER catalysts for AEMWEs,emphasizing their tunable electronic structures,abundant active sites,and alkaline stability.We systematically outline LDHs synthesis strategies(top-down/bottom-up approaches,and self-supporting LDHs engineering on the conductive substrates),and AEMWE component design,including membraneelectrode assembly optimization and ionomer-free architectures.Standardized evaluation protocols-short-circuit inspection,impedance spectroscopy,and durability assessment are detailed to benchmark performance.Moreover,recent advances in LDHs modification(cation/anion doping,heterojunction design,three-dimensional(3D)electrode structuring)are discussed for alkaline-fed systems,alongside emerging applications in seawater and pure-water electrolysis.By correlating material innovations with device-level metrics,this work provides a roadmap to address scalability challenges,offering perspectives on advancing AEMWEs for sustainable,large-scale hydrogen production. 展开更多
关键词 anion-exchange-membrane water electrolyzers layered double hydroxides anode construction feedstock solution membrane electrode assembly
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Effect and mechanism of Ti−O solid solution layer on interfacial bonding strength of cold roll bonded titanium/stainless steel laminated composite plate
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作者 Zhi-yan YANG Xue-feng LIU +1 位作者 Hong-ting CHEN Xin MA 《Transactions of Nonferrous Metals Society of China》 2026年第1期171-182,共12页
Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding str... Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding strength in titanium/stainless steel laminated composites were investigated.Results indicate that the hardened layer reduces the interfacial bonding strength from over 261 MPa to less than 204 MPa.During the cold roll-bonding process,the hardened layer fractures,leading to the formation of multi-scale cracks that are difficult for the stainless steel to fill.This not only hinders the development of an interlocking interface but also leads to the presence of numerous microcracks and hardened blocks along the nearly straight interface,consequently weakening the interfacial bonding strength.In metals with high work hardening rates,the conventional approach of enhancing interface interlocking and improving interfacial bonding strength by using a surface-hardened layer becomes less effective. 展开更多
关键词 titanium/stainless steel laminated composite plate Ti−O solid solution hardened layer interlocking interface formation mechanism interfacial bonding strength
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Hybridization Gap and Edge States in Strained-Layer InAs/In_(0.5)Ga_(0.5)Sb Quantum Spin Hall Insulator
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作者 Wenfeng Zhang Peizhe Jia +4 位作者 Wen-kai Lou Xinghao Wang Shaokui Su Kai Chang Rui-Rui Du 《Chinese Physics Letters》 2026年第1期179-183,共5页
The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges be... The hybridization gap in strained-layer InAs/In_(x)Ga_(1−x) Sb quantum spin Hall insulators(QSHIs)is significantly enhanced compared to binary InAs/GaSb QSHI structures,where the typical indium composition,x,ranges between 0.2 and 0.4.This enhancement prompts a critical question:to what extent can quantum wells(QWs)be strained while still preserving the fundamental QSHI phase?In this study,we demonstrate the controlled molecular beam epitaxial growth of highly strained-layer QWs with an indium composition of x=0.5.These structures possess a substantial compressive strain within the In_(0.5)Ga_(0.5)Sb QW.Detailed crystal structure analyses confirm the exceptional quality of the resulting epitaxial films,indicating coherent lattice structures and the absence of visible dislocations.Transport measurements further reveal that the QSHI phase in InAs/In_(0.5)Ga_(0.5)Sb QWs is robust and protected by time-reversal symmetry.Notably,the edge states in these systems exhibit giant magnetoresistance when subjected to a modest perpendicular magnetic field.This behavior is in agreement with the𝑍2 topological property predicted by the Bernevig–Hughes–Zhang model,confirming the preservation of topologically protected edge transport in the presence of enhanced bulk strain. 展开更多
关键词 strained layer quantum spin hall insulators qshis InAs Ga Sb edge states quantum wells qws be controlled molecular beam epitaxial growth hybridization gap quantum spin Hall insulator
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基于PML-IGVL边界条件的黏滞声波方程数值模拟
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作者 陈志立 汪勇 +3 位作者 桂志先 何幼娟 羊丹 年泽润 《石油地球物理勘探》 北大核心 2025年第2期392-401,共10页
地震勘探中的波动方程正演模拟受计算和存储能力的限制,只能在有限空间进行,需要对其设置边界条件。常用的完全匹配层(Perfect Match Layer,PML)是一种应用广泛的边界条件,需要对边界条件设定一定的层数,层数太大时会降低正演速度和增... 地震勘探中的波动方程正演模拟受计算和存储能力的限制,只能在有限空间进行,需要对其设置边界条件。常用的完全匹配层(Perfect Match Layer,PML)是一种应用广泛的边界条件,需要对边界条件设定一定的层数,层数太大时会降低正演速度和增大内存存储。因此,文中通过将PML边界条件和改进后的梯度黏弹边界(Improved Gradient Viscoelastic Layer,IGVL)结合提出一种PML-IGVL边界条件,同时,为了减少截断误差和数值频散,将PML-IGVL边界条件应用于紧致交错网格的黏滞声波方程中进行数值模拟。均匀介质和Marmousi模型中的波场数值模拟结果表明,相对于PML边界条件,PML-IGVL边界条件使用的边界厚度更小,在相同较低边界层数下,能更好地吸收反射波,同时能节省更多的存储空间,并提高正演效率,证明了PML-IGVL边界条件的有效性和优越性,是正演模拟中一种有效的边界吸收方法。 展开更多
关键词 紧致交错有限差分 黏滞声波方程 数值模拟 pml边界条件 改进梯度黏弹边界 pml-IGVL边界条件
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PML::RARα融合蛋白对白介素6受体的转录调控研究
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作者 赵玲玲 崔灿琦 糜坚青 《内科理论与实践》 2025年第2期146-151,共6页
目的:探讨PML::RARα融合蛋白对白介素6受体(interleukin-6 receptor,IL-6R)的调控机制,及IL-6R对急性早幼粒细胞白血病(acute promyelocytic leukemia,APL)细胞增殖和分化的影响。方法:采用GSE12662和GSE10358数据集分析APL细胞中IL-6... 目的:探讨PML::RARα融合蛋白对白介素6受体(interleukin-6 receptor,IL-6R)的调控机制,及IL-6R对急性早幼粒细胞白血病(acute promyelocytic leukemia,APL)细胞增殖和分化的影响。方法:采用GSE12662和GSE10358数据集分析APL细胞中IL-6R的表达水平;采用逆转录实时定量PCR(reverse transcription quantitative real-time PCR,RT-qPCR)检测全反式维A酸(all-trans retinoic acid,ATRA)处理前后的NB4细胞及Zn^(2+)诱导前后PR9细胞中IL-6R的mRNA表达;通过染色质免疫共沉淀(chromatin immunoprecipitation,ChIP)-seq数据分析、ChIPqPCR实验及双荧光素酶报告基因活性检测,研究PML::RARα对IL-6R的调控机制;构建IL-6R过表达质粒并通过逆转录病毒转染至NB4细胞,利用细胞计数试剂盒-8(cell counting kit-8,CCK-8)实验检测细胞增殖,流式细胞术检测NB4细胞的分化情况。结果:GSE12662数据集分析结果显示,APL患者早幼粒细胞中IL-6R的表达水平(12.20±0.41)显著低于正常早幼粒细胞(13.14±0.47,t=4.289,P<0.001)和中性粒细胞(14.82±0.40,t=12.35,P<0.001);GSE10358数据集分析结果显示,APL患者白血病细胞中IL-6R表达水平(5.93±0.84)显著低于非APL急性髓系白血病(acute myeloid leukemia,AML)患者(6.50±0.87,t=3.91,P<0.001)。APL患者细胞中IL-6R表达受PML::RARα融合蛋白的抑制,在APL中呈低表达模式,其机制为PML::RARα直接结合在IL-6R启动子区域,从而抑制其转录。在APL细胞株NB4中过表达IL-6R后,细胞增殖显著被抑制,转染4 d后,CCK-8检测到的吸光度值分别为0.86±0.01和0.40±0.01(t=32.66,P<0.001);同时细胞分化显著增强,CD11b阳性细胞比例由(3.10±1.22)%升高至(14.4±1.11)%(t=11.84,P<0.001)。结论:IL-6R是PML::RARα的靶基因,PML::RARα通过直接结合IL-6R启动子抑制其转录;明确IL-6R通过抑制APL细胞增殖并诱导其部分分化发挥其生物学功能。 展开更多
关键词 白介素6受体 急性早幼粒细胞白血病 pml::RARα 细胞增殖 细胞分化
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Modification of polypropylene separator with multifunctional layers to achieve highly stable sodium metal anode 被引量:1
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作者 Aadil Nabi Chishti Sikandar Iqbal +5 位作者 Muhammad Ali Moazzam Ali Samia Aman Hamid Hussain Muhammad Yousaf Yinzhu Jiang 《Journal of Energy Chemistry》 2025年第2期223-232,I0006,共11页
Separator modification is an effective approach to suppress dendrite growth to realize high-energy sodium metal batteries(SMBs)in practical applications,however,its success is mainly subject to surface modification.He... Separator modification is an effective approach to suppress dendrite growth to realize high-energy sodium metal batteries(SMBs)in practical applications,however,its success is mainly subject to surface modification.Herein,a separator with multifunctional layers composed of N-doped mesoporous hollow carbon spheres(HCS)as the inner layer and sodium fluoride(NaF)as the outer layer on commercial polypropylene separator(PP)is proposed(PP@HCS-NaF)to achieve stable cycling in SMB.At the molecular level,the inner HCS layer with a high content of pyrrolic-N induces the uniform Na^(+)flux as a potential Na^(+)redistributor for homogenous deposition,whereas its hollow mesoporous structure offers nanoporous buffers and ion channels to regulate Na^(+)ion distribution and uniform deposition.The outer layer(NaF)constructs the NaF-enriched robust solid electrolyte interphase layer,significantly lowering the Na^(+)ions diffusion barrier.Benefiting from these merits,higher electrochemical performances are achieved with multifunctional double-layered PP@HCS-NaF separators compared with single-layered separators(i.e.PP@HCS or PP@NaF)in SMBs.The Na‖Cu half-cell with PP@HCS-NaF offers stable cycling(280 cycles)with a high CE(99.6%),and Na‖Na symmetric cells demonstrate extended lifespans for over 6000 h at 1 mA cm^(-2)with a progressively stable overpotential of 9 mV.Remarkably,in Na‖NVP full-cells,the PP@HCS-NaF separator grants a stable capacity of~81 mA h g^(-1)after 3500 cycles at 1 C and an impressive rate capability performance(~70 mA h g^(-1)at 15 C). 展开更多
关键词 Sodium metal batteries Separator modification NaF-enriched SEI layer Multifunctional layers Enhanced cyclic stability
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Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions 被引量:1
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作者 Yuxue Mu Ning Zhang +7 位作者 Dongyu Wei Guoqing Yang Lilingxuan Yao Xinyue Xu Yang Li Junhui Xue Zuoming Zhang Tao Chen 《Neural Regeneration Research》 SCIE CAS 2025年第7期2116-2128,共13页
A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to ... A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness. 展开更多
关键词 glial fibrous acidic protein GLIOSIS Müller cells nerve growth factor neural differentiation neurodegeneration proteomic retinal degeneration retinal outer nuclear layer simulated weightlessness
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Absorption-Reflection-Transmission Power Coefficient Guiding Gradient Distribution of Magnetic MXene in Layered Composites for Electromagnetic Wave Absorption 被引量:3
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作者 Yang Zhou Wen Zhang +7 位作者 Dong Pan Zhaoyang Li Bing Zhou Ming Huang Liwei Mi Chuntai Liu Yuezhan Feng Changyu Shen 《Nano-Micro Letters》 2025年第6期466-481,共16页
The morphological distribution of absorbent in composites is equally important with absorbents for the overall electromagnetic properties,but it is often ignored.Herein,a comprehensive consideration including electrom... The morphological distribution of absorbent in composites is equally important with absorbents for the overall electromagnetic properties,but it is often ignored.Herein,a comprehensive consideration including electromagnetic component regulation,layered arrangement structure,and gradient concentration distribution was used to optimize impedance matching and enhance electromagnetic loss.On the microscale,the incorporation of magnetic Ni nanoparticles into MXene nanosheets(Ni@MXene)endows suitable intrinsic permittivity and permeability.On the macroscale,the layered arrangement of Ni@MXene increases the effective interaction area with electromagnetic waves,inducing multiple reflection/scattering effects.On this basis,according to the analysis of absorption,reflection,and transmission(A-R-T)power coefficients of layered composites,the gradient concentration distribution was constructed to realize the impedance matching at low-concentration surface layer,electromagnetic loss at middle concentration interlayer and microwave reflection at high-concentration bottom layer.Consequently,the layered gradient composite(LG5-10-15)achieves complete absorption coverage of X-band at thickness of 2.00-2.20 mm with RL_(min) of-68.67 dB at 9.85 GHz in 2.05 mm,which is 199.0%,12.6%,and 50.6%higher than non-layered,layered and layered descending gradient composites,respectively.Therefore,this work confirms the importance of layered gradient structure in improving absorption performance and broadens the design of high-performance microwave absorption materials. 展开更多
关键词 Magnetic MXene layered and gradient structure Power coefficient Electromagnetic wave absorption
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A layered aerogel composite with silica fibers,SiC nanowires,and silica aerogels ternary networks for thermal insulation at high-temperature 被引量:1
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作者 Qiong Wu Mengmeng Yang +10 位作者 Zhaofeng Chen Le Lu Zhudan Ma Yang Ding Longpan Yin Tianlong Liu Manna Li Lixia Yang Bin Hou Huanjun Zhu Sheng Cui 《Journal of Materials Science & Technology》 2025年第1期71-80,共10页
Due to excellent thermal insulation performance at room temperature and ultralow density,silica aero-gels are candidates for thermal insulation.However,at high temperatures,the thermal insulation prop-erty of silica a... Due to excellent thermal insulation performance at room temperature and ultralow density,silica aero-gels are candidates for thermal insulation.However,at high temperatures,the thermal insulation prop-erty of silica aerogels decreased greatly caused by transparency to heat radiation.Opacifiers introduced into silica sol can block heat radiation yet destroy the uniformity of aerogels.Herein,we designed and prepared a silica aerogel composite with oriented and layered silica fibers(SFs),SiC nanowires(SiC_(NWs)),and silica aerogels,which were prepared by papermaking,chemical vapor infiltration(CVI),and sol-gel respectively.Firstly,oriented and layered SFs made still air a wall to block heat transfer by the solid phase.Secondly,SiC_(NWs) were grown in situ on the surface of SFs evenly to weave into the network,and the network reduced the gaseous thermal conductivity by dividing cracks in SFs/SiC_(NWs)/SA.Thirdly,SiC_(NWs) weakened the heat transfer by radiation at high temperatures.Therefore,SFs/SiC_(NWs)/SA presented remarkable thermal insulation(0.017 W(m K)^(-1) at 25℃,0.0287 W(m K)^(-1) at 500℃,and 0.094 W(m K)^(-1) at 1000℃).Besides,SFs/SiC_(NWs)/SA exhibited remarkable thermal stability(no size transform after being heat treated at 1000℃ for 1800 s)and tensile strength(0.75 MPa).These integrated properties made SFs/SiC_(NWs)/SA a promising candidate for highly efficient thermal insulators. 展开更多
关键词 Silica aerogel Thermal insulation SiC nanowires layered structure
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Layered Double Hydroxide Nanosheets Incorporated Hierarchical Hydrogen Bonding Polymer Networks Coatings 被引量:1
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作者 Bifan Guo Yimin He +6 位作者 Yongming Chen Tianci Yang Chaohua Peng Weiang Luo Birong Zeng Yiting Xu Lizong Dai 《Nano-Micro Letters》 2025年第5期374-390,共17页
In recent decades,annual urban fire incidents,including those involving ancient wooden buildings burned,transportation,and solar panels,have increased,leading to significant loss of human life and property.Addressing ... In recent decades,annual urban fire incidents,including those involving ancient wooden buildings burned,transportation,and solar panels,have increased,leading to significant loss of human life and property.Addressing this issue without altering the surface morphology or interfering with optical behavior of flammable materials poses a substantial challenge.Herein,we present a transparent,low thickness,ceramifiable nanosystem coating composed of a highly adhesive base(poly(SSS1-co-HEMA1)),nanoscale layered double hydroxide sheets as ceramic precursors,and supramolecular melamine di-borate as an accelerator.We demonstrate that this hybrid coating can transform into a porous,fire-resistant protective layer with a highly thermostable vitreous phase upon exposure to flame/heat source.A nanosystem coating of just~100μm thickness can significantly increase the limiting oxygen index of wood(Pine)to 37.3%,dramatically reduce total heat release by 78.6%,and maintain low smoke toxicity(CIT_G=0.016).Detailed molecular force analysis,combined with a comprehensive examination of the underlying flame-retardant mechanisms,underscores the effectiveness of this coating.This work offers a strategy for creating efficient,environmentally friendly coatings with fire safety applications across various industries. 展开更多
关键词 NANOCOMPOSITES SUPRAMOLECULAR Flame retardancy Ceramic-like char layer Fire protection
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Research on Multi-Level Automatic Filling Optimization Design Method for Layered Cross-Sectional Layout of Umbilical 被引量:1
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作者 YIN Xu FAN Zhi-rui +4 位作者 CAO Dong-hui LIU Yu-jie LI Meng-shu YAN Jun YANG Zhi-xun 《China Ocean Engineering》 2025年第5期891-903,共13页
The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly comple... The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections. 展开更多
关键词 UMBILICAL cross-sectional layout multi-level filling layered layout optimization design
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Parameter optimization of the observation system for the South Yellow Sea strong shielding layer based on seismic illumination analysis 被引量:1
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作者 Yang Jia-Jia Chen Jian-Wen +5 位作者 Huang Fu-Qiang Yan Zhong-Hui Lei Bao-Hua Wang Xiao-Jie Xu Hua-Ning Liu Hong 《Applied Geophysics》 2025年第1期84-98,233,共16页
The seismic data of the Laoshan Uplift in the South Yellow Sea Basin reveal a low signal-tonoise ratio and low refl ection signal energy in the deep Mesozoic–Paleozoic strata.The main reason is that the Mesozoic-Pale... The seismic data of the Laoshan Uplift in the South Yellow Sea Basin reveal a low signal-tonoise ratio and low refl ection signal energy in the deep Mesozoic–Paleozoic strata.The main reason is that the Mesozoic-Paleozoic marine carbonate rock strata are directly covered by the Cenozoic terrestrial clastic rock strata,which form a strong shielding layer.To obtain the reflection signals of the strata below the strong shielding layer,a one-way wave equation bidirectional illumination analysis of the main observation system parameters was conducted by analyzing the mechanism of the strong shielding layer.Low-frequency seismic sources are assumed to have a high illumination intensity on the reflection layer below the strong shielding layer.Accordingly,optimized acquisition parameter suggestions were proposed,and reacquisition was performed at the existing survey line locations in the Laoshan Uplift area.The imaging of the newly acquired data in the middle and deep layers was drastically improved.It revealed the unconformity between the Sinian and Cambrian under the strong shielding layer.The study yielded new insights into the tectonic and sedimentary evolution of the Lower Paleozoic in the South Yellow Sea. 展开更多
关键词 illumination analysis acquisition parameters Laoshan Uplift strong shielding layer
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Insights into chemical-mechanical degradation and modification strategies of layered oxide cathode materials of sodium ion batteries 被引量:1
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作者 Tong Zhang Yuesen Li +4 位作者 Zihao Song Yaohui Huang Fei Li Shaoan Cheng Fujun Li 《Journal of Energy Chemistry》 2025年第4期294-315,共22页
Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising a... Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs. 展开更多
关键词 layered oxide cathode Failure mechanism Intercalation chemistry Sodium-ion batteries SUSTAINABILITY
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Achievable dual-strategy to stabilize Li-rich layered oxide interface by a one-step wet chemical reaction towards long oxygen redox reversibility 被引量:2
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作者 Bin He Yujie Dai +7 位作者 Shuai Jiang Dawei Chen Xilong Wang Jie Song Dan Xiao Qian Zhao Yan Meng Wei Feng 《Journal of Energy Chemistry》 2025年第2期120-131,I0004,共13页
Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capac... Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide(LLO),leading to voltage and capacity fading.Herein,the dual-strategy of Cr,B complex coating and local gradient doping is simultaneously achieved on LLO surface by a one-step wet chemical reaction at room temperature.Density functional theory(DFT)calculations prove that stable B-O and Cr-O bonds through the local gradient doping can significantly reduce the high-energy O 2p states of interfacial lattice O,which is also effective for the near-surface lattice O,thus greatly stabilizing the LLO surface,Besides,differential electrochemical mass spectrometry(DEMS)indicates that the Cr_(x)B complex coating can adequately inhibit oxygen release and prevents the migration or dissolution of transition metal ions,including allowing speedy Li^(+)migration,The voltage and capacity fading of the modified cathode(LLO-C_(r)B)are adequately suppressed,which are benefited from the uniformly dense cathode electrolyte interface(CEI)composed of balanced organic/inorganic composition.Therefore,the specific capacity of LLO-CrB after 200 cycles at 1C is 209.3 mA h g^(-1)(with a retention rate of 95.1%).This dual-strategy through a one-step wet chemical reaction is expected to be applied in the design and development of other anionic redox cathode materials. 展开更多
关键词 Lithium-rich layered oxide cathode One-step wet chemical reaction Surface coating Local gradient doping Interfacial oxygen
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Exploring corrosion protection evolution of rust layer on high -Cr-content weathering bridge steel in simulated tropical marine atmosphere 被引量:1
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作者 Bingxiao Shi Lizhi Qin +5 位作者 Di Xu Xuequn Cheng Chao Liu Guowei Yang Feifan Xu Xiaogang Li 《International Journal of Minerals,Metallurgy and Materials》 2025年第8期1913-1928,共16页
The rust layer is a critical factor in determining the corrosion resistance performance of weathering bridge steel.Understanding the evolution mechanism of this rust layer is fundamental for the design and optimizatio... The rust layer is a critical factor in determining the corrosion resistance performance of weathering bridge steel.Understanding the evolution mechanism of this rust layer is fundamental for the design and optimization of such steel.This study investigates the evolu-tion of the rust layer on high-Cr-content weathering bridge steel,using an atmospheric corrosion monitoring(ACM)sensor and big data mining techniques in a simulated tropical marine atmosphere.Results reveal that the protective properties of the rust layer follow a peri-odic pattern of“ascending–constant”rather than a continuous ascending.Correlation analysis indicates that this phenomenon is attributed to the introduction of Cr,which promotes the formation of FeCr_(2)O_(4) in the rust layer.FeCr_(2)O_(4) helps prevent chloride ions from penetrating the rust layer,exerting a protective effect.These findings provide a strong scientific foundation for the design and improvement of new high-Cr-content weathering bridge steels. 展开更多
关键词 high-Cr-content steel rust layer bridge steel corrosion chloride corrosion corrosion rate
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