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Chinese Physics B 2024年第7期33卷 126-135页

作者：邵晓光张捷鲁延娟 School of Automation Nanjing University of Science and TechnologyNanjing 210094China School of Electronics and Information Engineering Changchun University of Science and TechnologyChangchun 130022China

This paper addresses the issue of nonfragile state estimation for memristive recurrent neural networks with proportional delay and sensor saturations. In practical engineering, numerous unnecessary signals are transmitted to the estimator through the networks, which increases the burden of communication bandwidth. A dynamic event-triggered mechanism,instead of a static event-triggered mechanism, is employed to select useful data. By constructing a meaningful Lyapunov–Krasovskii functional, a delay-dependent criterion is derived in terms of linear matrix inequalities for ensuring the global asymptotic stability of the augmented system. In the end, two numerical simulations are employed to illustrate the feasibility and validity of the proposed theoretical results.

关键词： memristor-based neural networks proportional delays dynamic event-triggered mechanism sensor saturations

Boosting ammonia production in electrocatalytic NO_(x)reduction on a robust Fe/FeMoO_(4)catalyst

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Nano Research 2024年第7期17卷 5801-5806页

作者： Dong-Xue Liu Xin Deng Yong-Fu Zhu Zhe Meng Xue-Feng Sun Miao-Miao Shi Hai-Xia Zhong Jun-Min Yan Key Laboratory of Automobile Materials Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Electrocatalytic reduction of nitrate(NO_(3)^(−))and nitride(NO_(2)^(−))to ammonia(NH3)is of wide interest as a promising alternative to the energy-intensive Haber-Bosch route for mitigating the vast energy consumption and the accompanied carbon dioxide emission,as well as benefiting for the relevant sewage ***,exploring an efficient and low-cost catalyst with high atomic utilization that can effectively facilitate the slow multi-electron transfer process remains a grand ***,we present an efficient hydrogenation of NO_(3)^(−)/NO_(2)^(−)species to NH3 in both alkaline and neutral environments over the Fe_(2)(MoO_(4))_(3)derived hybrid electrocatalyst with the metallic Fe site on FeMoO_(4)(Fe/FeMoO_(4)).The Mo ingredient can play a synergistically positive role in further promoting the NH_(3) production on *** a result,Fe/FeMoO_(4)behaves well in the electrochemical NH_(3) generation from NO_(2)^(−)with a maximum NH_(3) Faradaic efficiency(FE)of 96.53%and 87.68%in alkaline and neutral electrolyte,corresponding to the NH_(3) yield rate of 640.68 and 302.56 mg·h^(−1)·mg_(cat.)^(−1),respectively,which outperforms the Fe and Mo counterpart and other similar catalyst,showing the robust catalytic capacity of each active site.

关键词： ammonia synthesis NO_(x)reduction synergistic effect alkaline/neutral electrolyte

Study on the influence of side-blown airflow velocities on plasma and combustion wave generated from fused silica induced by combined pulse laser

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Plasma Science and Technology 2024年第7期26卷 165-176页

作者：余昊蔡继兴毛洪涛王云鹏李忆李顺 Jilin Key Laboratory of Solid-State Laser Technology and Application School of PhysicsChangchun University of Science and TechnologyChangchun 130022People’s Republic of China Chongqing Research Institute Changchun University of Science and TechnologyChongqing 401135People’s Republic of China

This study examines the impact of variations in side-blowing airflow velocity on plasma generation,combustion wave propagation mechanisms,and surface damage in fused silica induced by a combined millisecond-nanosecond pulsed *** airflow rate and pulse delay are the main experimental *** evolution of plasma motion was recorded using ultrafast time-resolved optical *** experimental results demonstrate that the expansion velocities of the plasma and combustion wave are influenced differently by the sideblowing airflow at different airflow rates(0.2 Ma,0.4 Ma,and 0.6 Ma).As the flow rate of the sideblow air stream increases,the initial expansion velocities of the plasma and combustion wave gradually decrease,and the side-blow air stream increasingly suppresses the *** is important to note that the target vapor is always formed and ionized into plasma during the combined pulse laser ***,the side-blown airflow alone cannot completely clear the *** on the delay conditions,the pressure of the side-blowing airflow,the influence of inverse Bremsstrahlung radiation absorption and target surface absorption mechanisms can lead to a phenomenon known as the double combustion waves when using a nanosecond pulse *** simulation and experimental results are consistent,indicating the potential for further exploration of fused silica targets in the laser field.

关键词： different airflow speeds plasma combustion wave different pulse delay surface damage

Multi-distortion suppression for neutron radiographic images based on generative adversarial network

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Nuclear Science and Techniques 2024年第4期35卷 176-188页

作者： Cheng-Bo Meng Wang-Wei Zhu Zhen Zhang Zi-Tong Wang Chen-Yi Zhao Shuang Qiao Tian Zhang School of Physics Northeast Normal UniversityChangchun 130024China

Neutron radiography is a crucial nondestructive testing technology widely used in the aerospace,military,and nuclear ***,because of the physical limitations of neutron sources and collimators,the resulting neutron radiographic images inevitably exhibit multiple distortions,including noise,geometric unsharpness,and white ***,these distortions are particularly significant in compact neutron radiography systems with low neutron ***,in this study,we devised a multi-distortion suppression network that employs a modified generative adversarial network to improve the quality of degraded neutron radiographic *** neutron radiographic image datasets with various types and levels of distortion were built for the first time as multi-distortion suppression ***,the coordinate attention mechanism was incorporated into the backbone network to augment the capability of the proposed network to learn the abstract relationship between ideally clear and degraded *** experiments were performed;the results show that the proposed method can effectively suppress multiple distortions in real neutron radiographic images and achieve state-of-theart perceptual visual quality,thus demonstrating its application potential in neutron radiography.

关键词： Neutron radiography Multi-distortion suppression Generative adversarial network Coordinate attention mechanism

Image Fusion Based on Bioinspired Rattlesnake Visual Mechanism Under Lighting Environments of Day and Night Two Levels

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Journal of Bionic Engineering 2024年第3期21卷 1496-1510页

作者： Yong Wang Hongmin Zou College of Communication Engineering Jilin UniversityChangchun130012China

This study,grounded in Waxman fusion method,introduces an algorithm for the fusion of visible and infrared images,tailored to a two-level lighting environment,inspired by the mathematical model of the visual receptive field of rattlesnakes and the two-mode cells'*** research presented here is segmented into three *** the first segment,we design a preprocessing module to judge the ambient light intensity and divide the lighting environment into two levels:day and *** second segment proposes two distinct network structures designed specifically for these daytime and nighttime *** the daytime images,where visible light information is predominant,we feed the ON-VIS signal and the IR-enhanced visual signal into the central excitation and surrounding suppression regions of the ON-center receptive field in the B channel,***,for nighttime images where infrared information takes precedence,the ON-IR signal and the Visual-enhanced IR signal are separately input into the central excitation and surrounding suppression regions of the ON-center receptive field in the B *** outcome is a pseudo-color fused *** third segment employs five different no-reference image quality assessment methods to evaluate the quality of thirteen sets of pseudo-color images produced by fusing infrared and visible *** images are then compared with those obtained by six other methods cited in the relevant *** empirical results indicate that this study's outcomes surpass the comparative results in terms of average gradient and spatial *** one or two sets of fused images underperformed in terms of standard deviation and entropy when compared to the control *** sets of fused images did not perform as well as the comparison in the QAB/F *** conclusion,the fused images generated through the proposed method show superior performance in terms of scene detail,visual perception,and image sharpness

关键词： Rattlesnake Visible image Infrared image Daylight Bionic

The KAM theorem on the modulus of continuity about parameters

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Science China Mathematics 2024年第3期67卷 577-592页

作者： Zhicheng Tong Jiayin Du Yong Li School of Mathematics Jilin UniversityChangchun 130012China Institute of Mathematics Jilin UniversityChangchun 130012China School of Mathematics and Statistics Center for Mathematics and Interdisciplinary SciencesNortheast Normal UniversityChangchun 130024China

In this paper,we study the Hamiltonian systems H(y,x,ξ,ε)=〈ω(ξ),y〉+εP(y,x,ξ,ε),where ω and P are continuous about ξ.We prove that persistent invariant tori possess the same frequency as the unperturbed tori,under a certain transversality condition and a weak convexity condition for the frequency mapping ω.As a direct application,we prove a Kolmogorov-Arnold-Moser(KAM) theorem when the perturbation P holds arbitrary Holder continuity with respect to the parameter ξ.The infinite-dimensional case is also *** our knowledge,this is the first approach to the systems with the only continuity in the parameter beyond H?lder's type.

关键词： Hamiltonian systems invariant tori frequency-preserving weak regularity

Role of texture before rolling: a research based on texture and magnetic properties of 4.5 wt.% Si non-oriented electrical steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1973-1986页

作者： Yu-fan Wang Guo-qing Zu Shi-cheng Sun Ying Han Wei-wei Zhu Hui Wu Yu Zhao Xu Ran Key Laboratory of Advanced Structural Materials of Ministry of Education Changchun University of TechnologyChangchun 130012JilinChina CRRC changchun Railway Vehicles Co. Ltd.Changchun 130000JilinChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia

The evolution of microstructure,texture,and magnetic properties with random texture,near-copper texture,weak near-cube texture,and strong λ fiber(/ND(normal direction))before rolling of non-oriented electrical steel was *** recrystallized hot bands with different textures but similar grain sizes were prepared by pre-annealing at low-temperature and high-temperature normalization *** was observed that the final annealed products exhibited similar recrystallized *** contrast,the final annealed product with more 2 fiber before rolling exhibited a stronger cube *** the fiber before rolling becoming stronger,the proportion of(111)deformed matrices became larger,which could be observed in the early recrystallization *** overwhelmingly dominant 2 orientation nuclei are formed in the(111)deformed matrix and become the dominant ***,the best magnetic properties are obtained in the products with strong 2 fiber before rolling,corresponding to the strong cube texture and low anisotropyparameter.

关键词： Texture before rolling Non-oriented electrical steel-Nucleation Grain growth Magnetic property

Advances in self-assembly-based circularly polarized luminescent materials

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Science China Chemistry 2024年第10期67卷 3247-3257页

作者： Bing-Hao Liu Yang Zong Na Liu Zong-Quan Wu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China The School of Pharmaceutical Sciences Jilin UniversityChangchun 130021China

Circularly polarized luminescent(CPL)materials have garnered attention for their diverse applications,including three-dimensional(3D)imaging,bio-imaging,chiral sensing,and other emerging ***,the fabrication of CPL-activated materials required the use of chiral luminescent small *** introduction of the idea of self-assembly has transformed the production of CPL-activated materials,providing new and promising opportunities for their *** utilizing self-assembly,it is now feasible to produce chiral nano-assemblies with CPL activity not only from chiral molecules but also from non-chiral substances and inorganic *** addition,self-assembly routes provide a way to increase the asymmetry factor,creating possibilities for additional refinement and adjustment of CPL material *** review offers a summary of the current progress and developments in the self-assembly of small molecules and polymers,with a specific emphasis on their capacity to create or enhance CPL in different *** aim of this review is to inspire interest in optical materials that are based on the principles of self-assembly.

关键词： circularly polarized luminescence photochemistry self-assembly chiral materials

Housing vacancy identification in shrinking cities based on multi-source data:A case study of Fushun city in Northeast China

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Journal of Geographical Sciences 2024年第1期34卷 89-111页

作者： SUN Hongri ZHOU Guolei LIU Yanjun FU Hui JIN Yu School of Geographical Sciences Northeast Normal UniversityChangchun 130024China Northeast Institute of Geography and Agroecology CASChangchun 130102China

Urban shrinkage has attracted the attention of many geographers and urban planners in recent ***,there are fewer studies on vacant housing in shrinking ***,this study combines multi-source remote sensing images and urban building data to assess the spatiotemporal variation patterns of housing vacancy in a typical shrinking city in *** following points were obtained:(1)We developed an evaluation model to identify vacant residential buildings in shrinking cities by removing the contribution of nighttime lights from roads and non-residential buildings;(2)The residential building vacancy rate in Fushun city significantly increased from 2013 to 2020,resulting in a significant high-value clustering *** impact of urban shrinkage on vacant residential buildings was higher than that on vacant non-residential buildings;(3)The World Pop population data demonstrated consistent spatial distribution and trend of population change in Fushun with the residential building vacancy rate results,suggesting good reliability of the constructed evaluation model in this *** housing vacancies can help the local government to raise awareness of the housing vacancy problem in shrinking cities and to propose reasonable renewal strategies.

关键词： housing vacancy residential building vacancy urban shrinkage VIIRS

Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-Tian Zhang Ming-Xin Niu Qi Zhang Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates