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Emerging progress: photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： ze-Le Chen Qiang-Qiang li Armido Studer Jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry & Chemical Engineering Anhui University Organisch-Chemisches Institut Universitat Münster

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles, nucleophiles, diradicals, and radical acceptors in diverse transformations. In recent years, notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions. Various nitroso compounds like nitrosoarenes, acyloxy nitroso compounds, N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access. In this review, we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds, with particular emphasis on their role as bifunctional reagents and acceptors of radicals, carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes

Manufacture the conducting polymer with light

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Science China Chemistry 2025年第1期68卷 8-9页

作者： Yang li Tianyu li Yan ji Baoguang liu College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications

Poly(3,4-ethylenedioxythiophene) (PEDOT), heralded as the “king” of conducting polymers, is esteemed in bioelectronics for its mixed electronic and ionic conductivity, mechanical properties compatible with biological tissues, tunable healing ability and stability in diverse environments [1]. Based on additive manufacturing of three-dimensional structures,PEDOT realizes the implementation in the efficient production of flexible bioelectronics, the construction of intricate electrode-neural implantations, and the development of smart brain-computer-interfaces [2].

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First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

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Science China Earth Sciences 2025年第1期68卷 1-10页

作者： Yongping WANG Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU ze-Jun HU Bin li Key Laboratory for Polar Science Ministry of Natural Resources Polar Research Institute of China Institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology School of Earth and Space Sciences University of Science and Technology of China School of Electronic Information Wuhan University

The Medium-energy Electron Spectrometers(MES) is a space-borne instrument onboard Macao Science Satellite-1(MSS-1) dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development, including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch, all within the range of 1.5lightning discharges are definitively geo-located for these LEP *** LEP events occur within lightning and consist of 40–300 keV electrons.A preliminary observation result indicates that, with medium-energy electron detectors, MSS-1can present in-situ observations of large regions of enhanced background precipitation and reveal their fine spatiotemporal characteristics and spectral *** collaborative VLF ground-based measurements at the Great Wall Station, Antarctica also have a good correspondence with LEP measurements of *** observations also imply that lightning activity has a modulation effect on the energetic electron energy-spatial structure.

关键词： lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao Science Satellite-1

Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen li Leilei liang Baoshan Zhang Yi Yang Guangbin ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Perfluoropentane-based oxygen-loaded nanodroplets reduce microglial activation through metabolic reprogramming

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Neural Regeneration Research 2025年第4期20卷 1178-1191页

作者： Wanxian Luo Chuanhui Xu linxi li Yunxiang ji Yezhong Wang Yingjia li Yongyi Ye Department of Medicine Ultrasonics Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina Institute of Neuroscience Department of NeurosurgeryThe Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina

Microglia,the primary immune cells within the brain,have gained recognition as a promising therapeutic target for managing neurodegenerative diseases within the central nervous system,including Parkinson’s *** perfluorocarbon droplets have been reported to not only possess a high oxygen-carrying capacity,but also exhibit remarkable anti-inflammatory ***,the role of perfluoropentane in microglia-mediated central inflammatory reactions remains poorly *** this study,we developed perfluoropentane-based oxygen-loaded nanodroplets(PFP-OLNDs)and found that pretreatment with these droplets suppressed the lipopolysaccharide-induced activation of M1-type microglia in vitro and in vivo,and suppressed microglial activation in a mouse model of Parkinson’s *** suppression led to a reduction in the inflammatory response,oxidative stress,and cell migration capacity in ***,the neurotoxic effects were mitigated,which alleviated neuronal ***,ultrahigh-performance liquid chromatography–tandem mass spectrometry showed that the anti-inflammatory effects of PFP-OLNDs mainly resulted from the modulation of microglial metabolic *** further showed that PFP-OLNDs regulated microglial metabolic reprogramming through the AKT-mTOR-HIF-1α***,our findings suggest that the novel PFP-OLNDs constructed in this study alleviate microglia-mediated central inflammatory reactions through metabolic reprogramming.

关键词： metabolic reprogramming microglia microglial migration nanotherapy neurodegenerative diseases neuroinflammation oxygen-loaded nanodroplets Parkinson’s disease perfluoropentane ultra-performance liquid chromatography–mass spectrometry

MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self‑Powered Motion Sensing

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Nano-Micro Letters 2025年第3期17卷 265-279页

作者： Yu‑ze Wang Yu‑Chang Wang Ting‑Ting liu Quan‑liang Zhao Chen‑Sha li Mao‑Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Peking UniversityBeijing 100871People’s Republic of China School of Mechanical and Material Engineering North China University of TechnologyBeijing 100144People’s Republic of China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080People’s Republic of China

Polymeric microwave actuators combining tissue-like softness with programmablemicrowave-responsive deformation hold great promise for mobile intelligentdevices and bionic soft robots. However, their application is challenged by restricted electromagneticsensitivity and intricate sensing coupling. In this study, a sensitized polymericmicrowave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx(MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique spacechargepolarization and interfacial polarization, resulting in significant improvements of230% in the dielectric loss factor and 830% in the apparent efficiency of electromagneticenergy harvest. The sensitized microwave actuation demonstrates as the shortenedresponse time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (upto 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combinesdriving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of ~ 3 mV) duringactuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approachfor developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

Distributed optimal consensus control for multiagent systems based on event-triggered and prioritized experience replay strategies

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Science China(Information Sciences) 2025年第1期68卷 306-321页

作者： Cuijuan ZHANG lianghao ji Shasha YANG Xing GUO Huaqing li Chongqing Key Laboratory of Image Cognition Chongqing University of Posts and Telecommunications Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of Electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词： multiagent systems event-triggered mechanism prioritized experience replay dual-structured neural networks optimal consensus control

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印章结构对微接触印刷制备导电网格的影响

无机材料学报 2017年第7期32卷 713-718页

作者：辛智青李修姬磊李泽涛项飞翔刘世丽李路海北京印刷学院印刷与包装工程学院北京市印刷电子工程技术研究中心北京102600

为了在PET基底上制备精细的透明网格状导电图案,本工作利用微接触印刷高精度的优势,分别采用线条结构和网格结构的印章转印银纳米粒子导电油墨,分析了其转印过程,并讨论了印章结构对网格图案性能的影响。结果表明:采用线条结构的印章可... 详细信息

为了在PET基底上制备精细的透明网格状导电图案,本工作利用微接触印刷高精度的优势,分别采用线条结构和网格结构的印章转印银纳米粒子导电油墨,分析了其转印过程,并讨论了印章结构对网格图案性能的影响。结果表明:采用线条结构的印章可真实还原印章设计尺寸,避免了线条的扩展,有利于提高网格图案的透光率;同时,在交叉处墨层较厚可提高导电性。而采用网格结构印章可一次转移快速获得网格图案,但由于印章网格上相邻线条之间液桥的形成会使图案线宽增加,降低其透光率;采用间距较大的印章可使液桥断裂,得到边缘光滑的网格图案,但间距增大导致单位面积导电路径减少,降低其导电性。总之,采用线条结构印章有利于获得性能较好的网格图案,但两次转移过程相对复杂,需用时间较长。

关键词：微接触印刷网格图案导电油墨银纳米粒子

The finite element analysis of high-frequency vibrations of quartz crystal resonator structures

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The finite element analysis of high-frequency vibrations of ...