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Science China Chemistry 2024年第5期67卷 1589-1595页

作者： Xianrong zeng Feng-Hua Zhang Runchen Lai Xiaoyu Lin Zhaobin Wang Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Instrumentation and Service Center for Molecular SciencesWestlake UniversityHangzhou 310024China

Photoinduced ligand-to-metal charge transfer(LMCT) has emerged as an effective strategy for synthesizing organic molecules in a sustainable manner. However, the majority of existing reports on selective C(sp^(3))–H bond functionalization via photoinduced LMCT focus on the use of late transition metals or rare-earth metals for radical additions or cross-couplings. In contrast, the utilization of photoinduced LMCT with 3d early transition metals poses a significant challenge. Herein, we describe an unprecedented approach to allylic C(sp^(3))–H addition to aldehydes, employing chromium(Cr) complexes as catalysts through visible-light-induced LMCT. By investigating the reaction pathway through various mechanistic studies, including radical trapping, kinetic isotope effect(KIE) analysis, and transient absorption spectroscopy, valuable insights have been gained. The proposed mechanism suggests the intermediacy of bromine radicals through homolysis of the Cr–Br bond. Notably, this protocol expands our understanding of the photochemical properties of earth-abundant Cr complexes.

关键词： Cr catalysis photoinduced ligand-to-metal charge transfer hydrogen-atom transfer carbonyl addition

A Catalog of ^(13)CO Clumps from the MWISP in l=10°–20°

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Research in Astronomy and Astrophysics 2024年第5期24卷 218-234页

作者： Xiaoyu Luo Sheng Zheng Zhibo Jiang Zhiwei Chen Yao Huang Shuguang zeng Xiangyun zeng Rui Zhang Chen Long Guangrong Zhou Jinbo Hu Center for Astronomy and Space Sciences China Three Gorges UniversityYichang 443000China College of Electrical Engineering and New Energy China Three Gorges UniversityYichang 443000China College of Science China Three Gorges UniversityYichang 443000China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China

In this study, we present a catalog of molecular clumps extracted from ^(13)CO(J=1-0) emission data of the Milky Way Imaging Scroll Painting(MWISP) project. The data covers the inner Milky Way within the longitude range10°≤l≤20° and the latitude strip of |b|≤ 5°. 25. The workflow for the extraction of clumps, namely Facet-SS-3DClump, consists of two parts: the identification of clump candidates and their verification. First, Facet-SS-3DClump employs FacetClumps to identify clump candidates. Subsequently, high-confidence clumps are obtained by cross-matching with the clumps detected by other algorithms, such as dendrogram. Second, these high-confidence clumps are used as prior knowledge to train a semi-supervised deep clustering approach, SS-3D-Clump, which is applied to verify clump candidates detected by FacetClumps, providing confidence levels for the molecular clumps. Finally, the catalog comprising 18,757 molecular clumps was obtained using Facet-SS-3D-Clump, and the catalog is 90% complete above 37 K km s^(-1). We observe a significant deviation of the mean Galactic latitude for clumps within |b|≤ 2° from the midplane, with b=-0°.110. We found that 82.3% of the dust clumps correspond to ^(13)CO clumps by matching with Herschel infrared dust clumps. In the future, Facet-SS-3D-Clump will be applied to detect ^(13)CO clumps in the entire MWISP data.

关键词： ISM molecules methods data analysis-stars formation

Role of Stokes Drift in Ocean Dynamics Under Typhoon Conditions in the Bohai Sea

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Journal of Ocean University of China 2024年第1期23卷 33-45页

作者： LI Haoqian WAN Kai WANG Menghan DENG zeng’an CAO Yu North China Sea Marine Forecasting Center Qingdao 266061China Shandong Provincial Key Laboratory of Marine Ecology and Environment&Disaster Prevention and Mitigation Qingdao 266061China North China Sea Offshore Engineering Survey Institute Qingdao 266061China School of Marine Science and Technology Tianjin UniversityTianjin 300072China South China Sea Marine Forecasting Center Guangzhou 510006China

The effect of Stokes drift production(SDP),which includes Coriolis-Stokes forcing,Langmuir circulation,and Craik-Lei-bovich vortexes,on the upper ocean during typhoon passage in the Bohai Sea(BS),China,is investigated by using a coupled wave-current *** role of SDP in turbulent mixing and the further dynamics during the entire typhoon period are comprehensively *** results show that SDP greatly increases turbulent mixing at all depths under typhoon conditions by up to seven times that under normal weather *** generally strengthens sea surface cooling by more than 0.4℃,with the maximum reduction in sea surface temperature(SST)at the during-typhoon stage exceeding 2℃,which is approximately seven times larger than that under normal weather *** SDP-induced decrease in current speed can exceed 0.2ms^(-1),and the change in current direction is generally opposite the wind *** results suggest that Stokes drift depresses the effect of strong winds on currents by intensifying turbulent *** layer depth(MLD)is distinctly increased by O(1)during typhoons due to SDP and can deepen by more than *** addition,the continuous effects of SDP on SST,current,and MLD at the after-typhoon stage indi-cate a hysteretic response between SDP and typhoon actions.

关键词： Stokes drift production Langmuir turbulence rurbulent mixing typhoon coupled model

Optimal design for rubber concrete layered periodic foundations based on the analytical approximations of band gaps and mapping relations

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 593-608页

作者： Wu Qiaoyun Xu Zhifeng Xu Peishan zeng Wenxuan Chen Xuyong School of Civil Engineering and Architecture Wuhan Institute of TechnologyWuhan 430073China State Key Laboratory for Health and Safety of Bridge Structures Wuhan 430034China Wuhan Urban Construction Group Co. Ltd.Wuhan 430022China

The seismic performance of rubber concrete-layered periodic foundations are significantly influenced by their design,in which the band gaps play a paramount *** at providing better designs for these foundations,this study first proposes and validates the analytical formulas to approximate the bounds of the first few band *** addition,the mapping relations linking the frequencies of different band gaps are ***,an optimal design method for these foundations is developed,which is validated through an engineering *** is demonstrated that ensuring the superstructure’s resonance zones are completely covered by the corresponding periodic foundation’s band gaps can achieve satisfactory vibration attenuation effects,which is a good strategy for the design of rubber concrete layered periodic foundations.

关键词： periodic foundation band gap vibration attenuation seismic isolation optimal design

Social Radars: Finding Targets in Cyberspace for Cybersecurity

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 279-282页

作者： Lili Fan Changxian zeng Yutong Wang Jiaqi Ma Fei-Yue Wang School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China School of Science Dalian Minzu UniversityDalian 116600China State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90024 USA IEEE State Key Laboratory for Management and Control of Complex Systems Chinese Academy of SciencesBeijing 100190 Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China

INSPIRED by the insight from American political scientist Lasswell, who summarized the environmental role in societal surveillance [1], Schramm coined the term “social radar” [2] as it resembles the activities of radar in collecting and processing information, playing a crucial role in helping humans perceive changes in the internal and external environment and promptly adjusting adaptive behaviors.

关键词： prompt summarized insight

Pathophysiological changes of muscle after ischemic stroke:a secondary consequence of stroke injury

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Neural Regeneration Research 2024年第4期19卷 737-746页

作者： Hu Qi Dan Tian Fei Luan Ruocong Yang Nan zeng State Key Laboratory of Southwestern Chinese Medicine Resources Chengdu University of Traditional Chinese Medicine School of Pharmacy Chengdu University of Traditional Chinese Medicine Acupuncture and Tuina School Chengdu University of Traditional Chinese Medicine

Sufficient clinical evidence suggests that the damage caused by ischemic stroke to the body occurs not only in the acute phase but also during the recovery period,and that the latter has a greater impact on the long-term prognosis of the ***,current stroke studies have typically focused only on lesions in the central nervous system,ignoring secondary damage caused by this *** a phenomenon arises from the slow progress of pathophysiological studies examining the central nervous ***,the appropriate therapeutic time window and benefits of thrombolytic therapy are still controversial,leading scholars to explore more pragmatic intervention *** treatment measures targeting limb symptoms can greatly improve a patient’s quality of life,they have become a critical intervention *** the most vital component of the limbs,skeletal muscles have become potential points of *** this,to the best of our knowledge,there are no comprehensive reviews of pathophysiological changes and potential treatments for post-stroke skeletal *** current review seeks to fill a gap in the current understanding of the pathological processes and mechanisms of muscle wasting atrophy,inflammation,neuroregeneration,mitochondrial changes,and nutritional dysregulation in stroke *** addition,the challenges,as well as the optional solutions for individualized rehabilitation programs for stroke patients based on motor function are discussed.

关键词： inflammation ischemic stroke mitochondria muscle atrophy muscle fiber muscle nutrition quality of life rehabilitation ubiquitin

Isotropic sintering shrinkage of 3D glass-ceramic nanolattices:backbone preforming and mechanical enhancement

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International Journal of Extreme Manufacturing 2024年第2期6卷 418-426页

作者： Nianyao Chai Yunfan Yue Xiangyu Chen Zhongle zeng Sheng Li Xuewen Wang Center of Femtosecond Laser Manufacturing for Advanced Materials and Devices State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070People’s Republic of China National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu LaboratoryFoshan 528000People’s Republic of China International School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070People’s Republic of China

There is a perpetual pursuit for free-form glasses and ceramics featuring outstanding mechanical properties as well as chemical and thermal *** is a promising idea to shape inorganic materials in three-dimensional(3D)forms to reduce their weight while maintaining high mechanical properties.A popular strategy for the preparation of 3D inorganic materials is to mold the organic–inorganic hybrid photoresists into 3D micro-and nano-structures and remove the organic components by subsequent ***,due to the discrete arrangement of inorganic components in the organic-inorganic hybrid photoresists,it remains a huge challenge to attain isotropic shrinkage during ***,we demonstrate the isotropic sintering shrinkage by forming the consecutive–Si–O–Si–O–Zr–O–inorganic backbone in photoresists and fabricating 3D glass–ceramic nanolattices with enhanced mechanical *** femtosecond(fs)laser is used in two-photon polymerization(TPP)to fabricate 3D green body *** subsequent sintering at 1000℃,high-quality 3D glass–ceramic microstructures can be obtained with perfectly intact and smooth ***-suit compression experiments and finite-element simulations reveal that octahedral-truss(oct-truss)lattices possess remarkable adeptness in bearing stress concentration and maintain the structural integrity to resist rod bending,indicating that this structure is a candidate for preparing lightweight and high stiffness glass–ceramic nanolattices.3D printing of such glasses and ceramics has significant implications in a number of industrial applications,including metamaterials,microelectromechanical systems,photonic crystals,and damage-tolerant lightweight materials.

关键词： 3D printing isotropic shrinkage femtosecond laser two-photon polymerization structural glass-ceramics

Alkaline zinc-based flow battery: chemical stability, morphological evolution, and performance of zinc electrode with ionic liquid

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Frontiers of Materials Science 2024年第1期18卷 113-121页

作者： Tianyong Mao Jing Dai Meiqing Xin Deliang zeng Zhipeng Xie Jiangxi Province Key Laboratory of Power Batteries and Materials Jiangxi University of Science and TechnologyGanzhou 341000China

Zinc-based flow battery is an energy storage technology with good application prospects because of its advantages of abundant raw materials,low cost,and environmental *** chemical stability of zinc electrodes exposed to electrolyte is a very important issue for zinc-based *** paper reports on details of chemical stability of the zinc metal exposed to a series of solutions,as well as the relationship between the morphological evolution of zinc electrodes and their properties in an alkaline *** corrosion of zinc electrodes by the electrolyte will change their surface ***,we observed that chemical corrosion is not the main contributor to the evolution of zinc electrode surface morphology,but the main contributor is the Zn/Zn^(2+)electrode *** morphological evolution of zinc electrodes was controlled by using ionic liquids,1-ethyl-3-methylimidazolium acetate(EMIA),and 1-propylsulfonic-3-methylimidazolium tosylate(PSMIT),and the electrode performance was recorded during the morphological evolution *** was observed that the reversible change of zinc electrode morphology was accompanied by better electrode performance.

关键词： alkaline medium morphological evolution zinc-based flow battery new energy

Achieving near-infrared-light-mediated switchable friction regulation on MXene-based double network hydrogels

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Friction 2024年第1期12卷 39-51页

作者： Pengxi WU Cheng zeng Jinglun GUO Guoqiang LIU Feng ZHOU Weimin LIU Center of Advanced Lubrication and Sealing Materials State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

MXene possesses great potential in enriching the functionalities of hydrogels due to its unique metallic conductivity,high aspect ratio,near-infrared light(NIR light)responsiveness,and wide tunability,however,the poor compatibility of MXene with hydrogels limits further *** this work,we report a uniformly dispersed MXene-functionalized poly-N-isopropylacrylamide(PNIPAM)/poly-2-acrylamido-2-methyl-1-propanesulfonic acid(PAMPS)double network hydrogel(M–DN hydrogel)that can achieve switchable friction regulation by using the NIR *** dispersity of MXene in hydrogels was significantly improved by incorporating the chitosan(CS)*** M–DN hydrogel showed much low coefficient of friction(COF)at 25℃ due to the presence of hydration layer on hydrogel *** illuminating with the NIR light,M–DN hydrogel with good photothermal effect rapidly raised the temperature to above the lower critical solution temperature(LCST),which led to an obvious increase of surface COF owing to the destruction of the hydration *** addition,M–DN friction control hydrogel showed good recyclability and controllability by tuning“on-off”of the NIR *** work highlights the construction of functional MXene hydrogels for intelligent lubrication,which provides insight for interface sensing,controlled transmission,and flexible robotic arms.

关键词： MXene dispersion photothermal hydrogel near-infrared(NIR)light friction modulation