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Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang Yuefeng Yan zhen wang Guansheng Ma Dechang Jia Xiaoxiao Huang Yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted *** composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing He zhen wang Yuchen wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-Tang Liang Yu-gang Ma Xin-Li Sheng Qun wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

Mechanical Properties of Railway High-strength Manufactured Sand Concrete: Typical Lithology, Stone Powder Content and Strength Grade

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 194-203页

作者： wang zhen LI Huajian HUANG Fali YANG Zhiqiang WEN Jiaxin SHI Henan Railway Engineering Research Institute China Academy of Railway Science Corporation LimitedBeijing 100081China State Key Laboratory for Track Technology of High-Speed Railway Beijing 100081China

In order to achieve the large-scale application of manufactured sand in railway high-strength concrete structure,a series of high-strength manufactured sand concrete(HMC)are prepared by taking the manufactured sand lithology(tuff,limestone,basalt,granite),stone powder content(0,5%,10%,15%)and concrete strength grade(C60,C80,C100)as *** evolution of mechanical properties of HMC and the correlation between cubic compressive strength and other mechanical properties are *** to river sand,manufactured sand enhances the cubic compressive strength,axial compressive strength and elastic modulus of concrete,while its potential microcracks weaken the flexural strength and splitting tensile strength of *** powder content displays both positive and negative effects on mechanical properties of HMC,and the stone powder content is suggested to be less than 10%.The empirical formulas between cubic compressive strength and other mechanical properties are proposed.

关键词： manufactured sand concrete railway mechanical property lithology stone powder content

聚合物A/B共混理论:相平衡及Coil-to-Globule转变

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聚合物A/B共混理论:相平衡及Coil-to-Globule转变

川南地区下古生界页岩气储层微观孔隙结构表征及其对含气性的影响

中国化学会2017全国高分子学术论文报告会

作者：徐玉赐 zhen-gang wang 宁波大学 California Insititute of Technology

Flory-Huggins理论是描述聚合物共混里程碑式的工作,通过假设高分子A/B均匀混合,并用一个唯象的相互作用参数c来表示它们之间的相互作用从而得到体系的自由能。当大于临界c时候,共混体系会分相,形成稀相与浓相两相。但是在稀溶液的情况... 详细信息

Flory-Huggins理论是描述聚合物共混里程碑式的工作,通过假设高分子A/B均匀混合,并用一个唯象的相互作用参数c来表示它们之间的相互作用从而得到体系的自由能。当大于临界c时候,共混体系会分相,形成稀相与浓相两相。但是在稀溶液的情况下,体系真实的物理图像并不是Flory-Huggins所描述的均匀分布,而是具有局部的浓度涨落。我们通过考虑这种局部的浓度涨落,发现在稀溶液的情况下,F-H理论由于假设均匀分布,而过高的估计了体系相互作用能,进而极大的低估了溶解度极限;另一方面,稀相浓度与聚合度N的指数关系也并非为F-H所预测的N,而是N的关系。最后我们对局部涨落单链的Globule-to-Coil转变也进行了研究,发现随着chi的降低,单链分子会经历完全榻缩小球,到表面溶胀,然后再到Coil结构。

关键词： Flory-Huggins Theory Localized Fluctuation Self-Consistent Field Theory Coil-to-Globule Transition

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煤炭学报 2016年第9期41卷 2287-2297页

作者：王哲李贤庆周宝刚祁帅张吉振王刚徐红卫王飞宇中国矿业大学(北京)煤炭资源与安全开采国家重点实验室北京100083 中国矿业大学(北京)地球科学与测绘工程学院北京100083 中国石油大学(北京)油气资源与探测国家重点实验室北京102249 中国石油大学(北京)地球科学学院北京102249

运用普通扫描电镜、氩离子抛光—场发射扫描电镜、Image J2x软件分析、高压压汞、低温CO_2和N_2吸附实验方法,对川南地区下寒武统筇竹寺组和下志留统龙马溪组两套页岩气储层微观孔隙成因类型、孔隙结构特征及其对页岩含气性的影响进行... 详细信息

运用普通扫描电镜、氩离子抛光—场发射扫描电镜、Image J2x软件分析、高压压汞、低温CO_2和N_2吸附实验方法,对川南地区下寒武统筇竹寺组和下志留统龙马溪组两套页岩气储层微观孔隙成因类型、孔隙结构特征及其对页岩含气性的影响进行了研究。结果表明,川南地区下古生界页岩微观孔隙主要发育粒间孔、粒内孔、有机质孔和微裂缝等多种成因孔隙类型;下古生界页岩微观孔隙总面孔率为3.95%~7.48%,筇竹寺组页岩总面孔率和有机质孔面孔率低于龙马溪组页岩;下古生界页岩总孔容为(3.93~24.96)×10^(-3)m L/g,总比表面积为2.727~29.399 m^2/g,孔径为0.35~1.00,2.5~4.7和55~75 nm的孔隙是总孔容的主要贡献者,孔径为0.3~1.0,2.5~5.5 nm的孔隙主要提供了总比表面积,筇竹寺组页岩总孔容和总比表面积均较龙马溪组页岩要低;页岩微观孔隙的面孔率、有机质孔、孔容、比表面积、孔径分布均会影响页岩含气性。下古生界筇竹寺组和龙马溪组页岩在微观孔隙结构特征的上述差异,为揭示川南地区筇竹寺组与龙马溪组页岩含气性的差异提供了依据。

关键词：页岩气储层孔隙结构面孔率含气性下古生界川南地区

Optimizing electronic structure through point defect engineering for enhanced electrocatalytic energy conversion

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Green Energy & Environment 2025年第1期10卷 109-131页

作者： Wei Ma Jiahao Yao Fang Xie Xinqi wang Hao Wan Xiangjian Shen Lili Zhang Menggai Jiao zhen Zhou Interdisciplinary Research Center for Sustainable Energy Science and Engineering(IRC4SE2) School of Chemical EngineeringZhengzhou UniversityHenan450001China

Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic *** introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active *** optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of *** elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization ***,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse *** underscores the pivotal role of point defects in enhancing catalytic *** last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials.

关键词： Point defect engineering Doping Vacancy Electrocatalysis Electronic structure

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静电场中Ca原子里德堡态的能级结构

物理学报 1989年第3期38卷 481-486页

作者：张森邱济真王刚浙江大学物理系

用两步激发和光电离方法,在0—8kV/cm电场范围内,测定了Ca原子n=10至n=13附近m=0的Stark光谱。实验结果显示,3d^(23)P_0及3d^(23)P_2价态受到n=12Stark簇的排斥。观察到与价态有关的干涉现象及其随电场大小的改变。讨论了零场非简并态... 详细信息

用两步激发和光电离方法,在0—8kV/cm电场范围内,测定了Ca原子n=10至n=13附近m=0的Stark光谱。实验结果显示,3d^(23)P_0及3d^(23)P_2价态受到n=12Stark簇的排斥。观察到与价态有关的干涉现象及其随电场大小的改变。讨论了零场非简并态、价态及Stark簇之间的能级交叉和抗交叉结构。

关键词：静电场 Ca 原子里德堡态能级

Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen Chen Xiaolin Zeng Le wang Wenwu Zhang gang Li Xing Cheng Peiqiang Su Yong Wan Xiang Li Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury