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Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong Liu Siyu Zhang Dan Qu Xuejiao Zhou Moxuan yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou kai Tao Mengyang Li Bing Wei Hongjing Wu Mengyang Li Bing Wei Hongjing Wu School of Physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption

Hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： kai yin Xiaopeng Liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting *** effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm *** experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and *** 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium *** 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm Hydrogen absorption Nitrogen absorption Rare earths

Drag Effects of Solute and Second Phase Distributions on the Grain Growth Kinetics of Pre-Extruded Mg-6Zn Alloy

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Journal of Materials Science & Technology 2016年第12期32卷 1260-1266页

作者： Zhaoyang Jin Donghua Yu Xintong Wu kai yin kai Yan College of Mechanical Engineering Yangzhou University

In order to control the grain size during hot forming,grain growth behavior of a pre-extruded Mg-6Zn magnesium alloy and its correlation with solute and second phase distribution were *** annealing was conducted on a Gleeble-1500 thermo-mechanical *** mean grain size Dg of each annealed specimen was measured by the quantitative metallography *** grain growth kinetics of the Mg-6Zn alloy annealed at 473-623 K was obtained as Dg^4- Dg0^4=2.25 ×10^11 exp（-95450）by the least square linear regression *** deviation of grain growth exponent n = 4 from the theoretical value of 2 may be attributed to the presence of solute zinc and second phases which will retard the boundary *** observations show that the non-uniform distribution of grain size for samples pre-extruded or annealed at low temperatures is closely related to the non-uniform distribution of fine and dispersed second phases but not to the non-uniform distribution of solute *** indicates that second phase pinning effect plays an important role in microstructure refinement.

关键词： Grain growth kinetics Second phase distribution Solute dragging Magnesium alloys

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区域敏感的场景图生成方法

北京工业大学学报 2025年第1期51卷 51-58页

作者：王立春付芳玉徐凯徐洪波尹宝才北京工业大学信息学部北京100124 北京工业大学多媒体与智能软件技术北京市重点实验室北京100124

针对基于关系边界框提取的谓词特征粒度相对较粗的问题,提出区域敏感的场景图生成(region-sensitive scene graph generation,RS-SGG)方法。谓词特征提取模块将关系边界框分为4个区域,基于自注意力机制抑制关系边界框中与关系分类无关... 详细信息

针对基于关系边界框提取的谓词特征粒度相对较粗的问题,提出区域敏感的场景图生成(region-sensitive scene graph generation,RS-SGG)方法。谓词特征提取模块将关系边界框分为4个区域,基于自注意力机制抑制关系边界框中与关系分类无关的背景区域。关系特征解码器在进行关系预测时不仅考虑了物体对的视觉特征和语义特征,也考虑了物体对的位置特征。在视觉基因组(visual genome,VG)数据集上分别计算了RS-SGG方法针对场景图生成、场景图分类和谓词分类3个子任务的图约束召回率和无图约束召回率,并与主流的场景图生成方法进行了比较。实验结果表明,RS-SGG的图约束召回率和无图约束召回率均优于主流方法。此外,可视化实验结果也进一步证明了所提出方法的有效性。

关键词：图像理解场景图生成物体分类关系分类区域感知自注意力机制

Copper-Initiated Radical Dearomative 2,5-Alkylarylation of Furans via Trihalomethylation/Spirocyclization Cascade

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Chinese Journal of Chemistry 2022年第24期40卷 2893-2899页

作者： Wenkun Luo kai Jiang Biaolin yin Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhouGuangdong510640 China Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation School of Chemistry and EngineeringChangsha University of Science and TechnologyChangshaHunan410114 China

Here is an operable and rare strategy for copper-initiated radical dearomative 2,5-alkylarylation of furan. By means of this strategy, we realized the dearomatization of furans to construct spirooxindoles with good yi... 详细信息

关键词： Copper Radical reactions Dearomatization Trihalomethylation Spiro compounds

Challenges to quantitative applications of Landsat observations for the urban thermal environment

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Journal of Environmental Sciences 2017年第9期29卷 80-88页

作者： Feng Chen Song Yang kai yin Paul Chan School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 519082China Institute of Earth Climate and Environment System Sun Yat-sen UniversityOuangzhou 510275China Fujian Key Laboratory of Sensing and Computing.for Smart City Xiarnen UniversityXiarnen 361005China Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijing 10094China Climate Decision LLC BethesdaMDUSA

Since the launch of its first satellite in 1972, the Landsat program has operated continuously for more than forty years. A large data archive collected by the Landsat program significantly benefits both the academic community and society. Thermal imagery from Landsat sensors, provided with relatively high spatial resolution, is suitable for monitoring urban thermal environment. Growing use of Landsat data in monitoring urban thermal environment is demonstrated by increasing publications on this subject, especially over the last decade. Urban thermal environment is usually delineated by land surface temperature（LST）. However, the quantitative and accurate estimation of LST from Landsat data is still a challenge, especially for urban areas. This paper will discuss the main challenges for urban LST retrieval, including urban surface emissivity, atmospheric correction, radiometric calibration, and validation. In addition, we will discuss general challenges confronting the continuity of quantitative applications of Landsat observations. These challenges arise mainly from the scan line corrector failure of the Landsat 7 ETM ＋ and channel differences among sensors. Based on these investigations, the concerns are to：（1） show general users the limitation and possible uncertainty of the retrieved urban LST from the single thermal channel of Landsat sensors;（2） emphasize efforts which should be done for the quantitative applications of Landsat data; and（3） understand the potential challenges for the continuity of Landsat observation（i.e., thermal infrared） for global change monitoring, while several climate data record programs being in progress.

关键词： Remote sensing Radiometric calibration SLC-off Surface temperature Data consistency

Finite element modelling on microstructure evolution during multi-pass hot compression for AZ31 alloys using incremental method

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Journal of Materials Science & Technology 2017年第11期33卷 1255-1262页

作者： Zhaoyang Jin kai yin kai Yan Defeng Wu Juan Liu Zhenshan Cui School of Mechanical Engineering Yangzhou University Yangzhou 225127 China School of Chemistry & Chemical Engineering Yangzhou University Yangzhou 225127 China Nationai Die and Mold CAD Engineering Research Center Shanghaifiao Tong University Shanghai 200030 China

Based on the principle of piecewise linearization, the incremental forms of microstructure evolution models were integrated into the thermo-mechanical coupled finite element（FE） model to simulate nonlinear microstructure evolution during multi-pass hot deformation. This is an unsteady-state deformation where dynamic recrystallization（DRX）, meta-dynamic recrystallization（MDRX）, static recrystallization（SRX） and grain growth（GG） take place during hot deformation or deformation interval. The distributions of deformation and microstructure for cylindrical AZ31 sample during single-pass and double-pass hot compressions were quantitatively calculated and compared with the metallographic observation. It is shown that both the deformation and microstructure are non-uniformly distributed due to the presence of friction between the die and the flat end of sample. The average grain size and its standard deviation under the double-pass hot compression are slightly smaller than those under single-pass *** simulated average grain sizes agree well with the experiments, which validates that the developed FE model on the basis of incremental forms of microstructure evolution models is reasonable.

关键词： Incremental method Microstructure evolution Multi-pass hot compression Finite element method Magnesium alloys

Reflection and transmission coefficient approximation at weak-contrast interfaces for strong VTI media

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Science China Earth Sciences 2024年第12期67卷 3914-3938页

作者： Xingyao yin Yaming YANG kai LIANG Kun LI National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China School of Geosciences China University of Petroleum(East China)Qingdao 266580China Laoshan Laboratory Qingdao 266580China

Reflection and transmission(R/T)responses characterize the propagation and energy distribution of incident and reflected waves on both sides of an interface which is crucial for imaging,amplitude variation with offset(AVO),and seismic inversion *** media are typically characterized by anisotropy which can have a significant impact on the R/T response,even at small incident ***,anisotropic media problems including reflection,transmission,and inversion are generally discussed under a weak anisotropy ***,this assumption is no longer valid in cases of large angles where anisotropy enhancement exacerbates the error of the conventional R/T coefficient *** R/T coefficient approximation method for strong VTI media was proposed based on the assumption of weak-contrast of the *** contrast to the conventional approach,which simplifies the phase velocity and polarization in an anisotropic background,the phase velocity and polarization at the weak-contrast interface of the elasticity and anisotropy parameters were approximated using a combination of the anisotropic background and perturbation ***,a first-order approximation of the R/T coefficients for the VTI media characterized by elastic and anisotropic parameters was derived using Cramer's law to invert the anisotropic background matrix,avoiding the assumption of weak ***,the exact solution of the Zoeppritz equations was used to correct the isotropic part,improving the accuracy of the R/T coefficients at interfaces with high-velocity *** tests on four classes of typical interfaces showed that the derived equations can be degraded to the Aki approximation in isotropic media,while exhibiting high accuracy in strong VTI *** analyses showed that a linear approximation that facilitates seismic inversion can be obtained by taking the S-to P-velocity ratio and anisotropy parameters in the coefficient terms a

关键词： Reflection and transmission coefficients Strong anisotropy VTI media Weak-contrast Phase-velocity Polarization

Inflammation,lipid metabolism dysfunction,and hypertension:Active research fields in atherosclerosis-related cardiovascular disease in China

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Science China(Life Sciences) 2011年第10期54卷 976-979页

作者： yin kai TANG ChaoKe Institute of Cardiovascular Research Key LaboratoryJbr Atherosclerology of Hunan Province Life Science Research Center University of South China Hengyang 421001 China

Atherosclerosis-related cardiovascular disease is one of the leading causes of death in China [1]. With advances in our understanding of the molecular mechanisms of atherosclerosis vascular inflammation, lipid metabolism dysfunction, and hypertension are regarded as the main pathogenetic pathways of both early atherogenesis and advanced plaque rupture [2,3]. Currently, much attention is being paid to the control of these pathways, which offers the potential for development of novel therapeutic approaches in the treatment of cardiovascular disease in China.

关键词：动脉粥样硬化心血管疾病高血压功能障碍脂质代谢中国炎症分子机制