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ON POTENT ELEMENTS AND PSEUDO CLEAN RINGS

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数学杂志 2025年第1期45卷 39-47页

作者： DING Yan GAO han-peng LIU Xin-yi YAN zi-yi ZhanG Ting School of Mathematical Sciences Anhui UniversityHefei 230601China

In this paper,potent index of an element and pseudo clean rings are *** properties and examples of pseudo clean rings are *** also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings are ***,we prove... 详细信息

关键词： clean rings strongly J-clean rings pseudo clean rings potent elements

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信息化视角下的电子档案四性检测研究与探索

办公自动化 2025年第1期30卷 75-77页

作者：郎吉韩洁中国航空工业集团公司第一飞机设计研究院西安710089

真实性、完整性、可用性、安全性是电子文件能成为档案的本质特征,也是电子档案具备法律效力的前提。文章分析电子档案四性检测的研究现状,梳理电子档案的归档、移交与接收、长期保存等三个环节的四性检测要求,并以电子档案四性检测功... 详细信息

真实性、完整性、可用性、安全性是电子文件能成为档案的本质特征,也是电子档案具备法律效力的前提。文章分析电子档案四性检测的研究现状,梳理电子档案的归档、移交与接收、长期保存等三个环节的四性检测要求,并以电子档案四性检测功能开发与应用实例为依据开展实践研究,以期为四性检测嵌入电子档案档案管理流程提供借鉴和参考。

关键词：电子档案四性检测应用

Terahertz dual-beam leaky-wave antenna based on multi-mode spoof surface plasmon polariton waveguide

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Optoelectronics Letters 2025年

作者： BAI Yukun han Yuanqing Tianjin Key Laboratory of Film Electronic and Communication Devices， Engineering Research Center of Optoelectronic Devices and Communication Technology， Ministry of Education， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

In this paper， a terahertz dual-beam leaky-wave antenna (LWA) based on a multi-mode spoof surface plasmon polariton (SSPP) waveguide is proposed. By dispersion engineering of the SSPP transmission line (SSPP TL)， multiple modes are excited on the SSPP TL. A dual-beam LWA is constructed based on the radiation from the first space harmonics of the guided fundamental mode and the first higher-order mode. The simulation results show that the antenna radiates frequency-dependent dual beams in the 1.9 ～ 2.6 THz operating frequency band. The average gains for the two beams are 12.9 dBi and 8.2 dBi， respectively. The compact dual-beam LWA is promising in the application of wireless communication and radar systems.

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A Fluorine-Functionalized 3D Covalent Organic Framework with Entangled 2D Layers

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Chinese Journal of Polymer Science 2024年第8期42卷 1210-1216页

作者： Li-Bang Xiao zi-han Wu Jun-jie Xin Yuan-Peng Cheng Bo Gui Jun-Liang Sun Cheng Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China

Constructing three dimensional(3D)covalent organic frameworks(COFs)through the entanglement of two dimensional(2D)nets is a promising but underdeveloped ***,we report the design and synthesis of a fluorine functionalized 3DCOF(3D-An-COF-F)formed by entangled 2D sql *** structure of 3D-An-COF-F was determined by the combination of continuous rotation electron diffraction technique and modelling based on the chemical information from real ***,compared to the isostructural 3D-An-COF without F atom s,3DAn-COF-F showed an improved CO_(2)sorption ability and higher CO_(2)/N_(2)*** study not only demonstrated the generality of constructing 3D COFs with entangled 2D nets by introducing bulky groups vertically in planar building blocks,but also will expand the diversity of 3D COFs for various applications.

关键词： 3D covalent organic frameworks Fluorine Entangled 2D layers Electron diffraction CO_(2)adsorption

Revealing the effect of OH-concentration change on the formation of FeNi layered double hydroxides

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Science China Materials 2023年第7期66卷 2949-2950页

作者： zi-Meng han Shu-Hong Yu Department of Chemistry Institute of Biomimetic Materials&ChemistryDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China

Benefiting from unique physicochemical properties,layered double hydroxides(LDHs)are attracting intense interest in a wide range of applications[1,2].The research community has been dedicated to synthesizing LDHs mainly via various wet chemical strategies including hydrothermal/solvothermal methods[3],co-precipitation[4],electrodeposition[5].

关键词： hydroxide layered double

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao Meng Tao Chen Yu han Jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man han Deyang Zeng Wei Tan Xingxing Chen Shuyuan Bai Qiong Wu Yushan Chen Zhen Wei Yufei Mei Yan Zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to Wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area

Breaking the structural symmetry of active sites in zeolite imidazolate framework for enhanced CO2 photoreduction

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Science China Chemistry 2025年

作者： Yupeng han Yayu Yan Qiaohong Li Xin Wu Fei Wang Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences College of Chemistry Fuzhou University

Adjusting the structure and composition of active sites is a highly effective method for activating linear ***, precise control of interfacial chemistry within molecular-scale environments presents a significant challenge in heterogeneous catalysis. In our study, we present symmetry-broken Mo-O-Co triple-atom active sites within the hybrid zeolite imidazole framework HziF-CoMo. These sites disrupt the electronic balance and create a weak built-in electric field, thus promoting photocatalytic CO2reduction. The CO yield over HziF-CoMo is improved to 3.1 mmol g-1h-1, which is over four times higher than the parent cobalt-imidazole framework MAF-6-Co. Both experimental and theoretical studies indicate that electronic modulation through the symmetry-breaking Mo-O-Co moiety acts as an organizing knob to accelerate charge separation and result in more carriers participating in the catalytic reaction. This work provides important insights into optimizing site-related electronic structures for targeted photocatalytic reactions.

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A mini-review on recent progress of new sensitizers for luminescence of lanthanide doped nanomaterials

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Nano Research 2020年第7期13卷 1795-1809页

作者： Hongxin Zhang zi-han Chen Xuan Liu Fan Zhang Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsState Key Laboratory of Molecular Engineering of Polymers and iChemFudan UniversityShanghai 200433China

Trivalent lanthanide(Ln2+)doped luminescent nanocrystals are promising for applications ranging from biosensor,lasing,super-resolution nanoscopy,information security and so *** the utility prospect is of great attractions,the light absorption of these lanthanide doped nanocrystals is inherently weak due to the electric dipole-forbidden 4f→4f *** worse,the quantum yields of upconverison nanocrystals are very low,which will unavoidably hinder their further *** a typical lanthanide luminescent nanosystem,both sensitizers as light absorption centers and activators as light emitting centers are necessary and important for desired luminescence *** various sensitization systems,only Yb3+and Nd+are considered as the most efficient ***,the corresponding excitation wavelengths are strictly limited around 980 and 808 *** enrich excitation wavelengths and boost luminescence intensity,exploring more sensitization units that possess larger absorption cross section,higher efficiency of energy transfer process and independent excitation is imperative and beneficial for the demands of different applications,such as broadened absorption in near infrared(NIR)region for higher conversion efficiency of solar cells,prolonged excitation wavelength to second near infrared windows region(NIR Ⅱ,1,000-1,700 nm)for in vivo fluorescence imaging with deeper tissue depth and higher spatial resolution,more orthogonal excitations and emissions to improve optical multiplexing,and so ***,in the review,we primarily conclude several major energy transfer mechanisms from sensitizers to *** we present three kinds of sensitizers,including lanthanide ions,organic dyes and quantum dots(QDs),and introduce the newly designed sensitization system that allows us to exploit superior excitation wavelength and amplity luminescence ***,several future challenges and opportunities for the sensitizing strategies are discuss

关键词： lanthanide luminescenee new sensitizers organic dyes quantum dots