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Ni-Catalyzed Enantioselective Difunctionalization of Alkynes to Azepine Derivatives Bearing a Quaternary Center and an Unprotected Imine

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Chinese Journal of Chemistry 2024年第8期42卷 873-878页

作者： jian Long Zhiwu Lu Xiao-Lin Li Peng Xue wen-Bo Liu Engineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei430072 China

Comprehensive Summary,The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)-catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all-carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram-scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven-membered nitrogen heterocycles.

关键词： Nickel Asymmetric catalysis N-Heterocycles Alkyne functionalization Quaternary centers

Bi_(2)S_(3) nanofiber bunch for highly efficient CO_(2) electroreduction to formate at low overpotential

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Rare Metals 2024年第7期43卷 3391-3399页

作者： Li Wang wen-Ke Gui Shan jiang Liang Wang jian-Ping Yang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Centre for Catalysis and Clean Energy Griffith UniversityGold Coast CampusGold CoastQLD 4222Australia

Electrochemical conversion of CO_(2) into valuable chemicals represents a promising strategy to alleviate the environmental issues caused by excessive CO_(2) levels in the *** this work,Bi_(2)S_(3) with different morphologies have been fabricated via facile hydrothermal method to investigate the CO_(2) electrochemical reduction process.

关键词： process. facile Electrochemical

O_(2) adsorption on Fe_(3)O_(4) (110) surface and effect of gangue element Al doping: combined study of binding experiment and ab initio molecular dynamics

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Journal of Iron and Steel Research International 2024年第4期31卷 810-827页

作者： Zheng-jian Liu Hui-qing jiang Yao-zu Wang jian-liang Zhang Hong-mei Qiao An-yang Zheng Fang-yu guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Beijing Shougang Co. Ltd.Qian'an 064404HebeiChina Department of Physics National University of Defense TechnologyChangsha 410128HunanChina

At high temperature,the chemical reaction mechanism at the interface of magnetite and the influence mechanism of gangue element Al on the oxidation performance of magnetite are not *** addition,due to the limitation of existing experimental equipment,it is difficult to clarify the interface reaction mechanism in the oxidation process and the influence mechanism of Al on the surface oxidation reaction of Fe_(3)O_(4) at an atomic scale at high *** surface oxidation reaction mechanism of magnetite and the influence mechanism of Al on the oxidation of magnetite were studied by experiments and AIMD(ab initio molecular dynamics).The experimental results show that the existence of Al_(2)O_(3) will reduce the initial oxidation temperature and comprehensive oxidation performance of *** AIMD results show that aluminum can accelerate the interface reaction rate of Fe_(3)O_(4) in the high-temperature oxidation atmosphere,but the strong Al-O binding ability is not conducive to the transfer of O atoms in the oxidation process.

关键词： Ironmaking Magnetite oxidation Interface reaction Adsorption-Gangue aluminum AIMD

NIR-Ⅱ responsive Janus nanoparticles amplify immunogenic cell death for enhanced cancer immunotherapy

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Science China(Technological Sciences) 2024年第1期67卷 321-329页

作者： CHEN BeiBei guo KangLi WANG HaoRan XU Fu-jian WANG JuLin ZHAO NaNa State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Biomedical Materials of Natural Macromolecules(Beijing University of Chemical Technology) Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China College of Materials Sciences and Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing University of Chemical TechnologyBeijing 100029China

Immunotherapy brings new hope for tumor treatment by inducing immunogenic cell death(ICD)of tumor ***,insufficient immunogenicity and low immune response rate greatly limit antitumor ***,by optimizing the composition and morphology,the rational design of Janus nanoparticles composed of Fe_(3)O_(4) nanospheres and SiO_(2)nanorods was realized for enhanced cancer immunotherapy through amplified *** glucose oxidase(GOx)was loaded by the Janus nanoparticles,the resultant M-FS-GOx consumes glucose at tumor sites to generate gluconic acid and hydrogen peroxide(H_(2)O_(2))for starvation therapy while the H_(2)O_(2)supply promotes the production of highly toxic·OH to achieve effective chemodynamic therapy(CDT).Under a 1064 nm light irradiation,the photothermal effect of M-FS-GOx enhances the enzyme activity of GOx for improved starvation ***,both tumor-associated antigens released during the process of ICD and the intrinsic immunoadjuvant property of M-FS-GOx stimulate dendritic cell maturation to activate antitumor immune *** work provides a promising strategy for the construction of Janus nanoparticles to achieve enhanced cancer immunotherapy through combination therapy-amplified ICD.

关键词： Janus nanoparticles immunogenic cell death cancer immunotherapy

Broadband and fabrication-tolerant 3-dB couplers with topological valley edge modes

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Light(Science & Applications) 2024年第8期13卷 1623-1630页

作者： guo-Jing Tang Xiao-Dong Chen Lu Sun Chao-Heng guo Meng-Yu Li Zhong-Tao Tian Hou-Hong Chen Hong-Wei Wang Qi-Yao Sun Ying-Di Pan Xin-Tao He Yi-Kai Su jian-wen Dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China

3-dB couplers,which are commonly used in photonic integrated circuits for on-chip information processing,precision measurement,and quantum computing,face challenges in achieving robust performance due to their limited 3-dB bandwidths and sensitivity to fabrication *** address this,we introduce topological physics to nanophotonics,developing a framework for topological 3-dB *** couplers exhibit broad working wavelength range and robustness against fabrication dimensional *** leveraging valley-Hall topology and mirror symmetry,the photonic-crystal-slab couplers achieve ideal 3-dB splitting characterized by a wavelength-insensitive scattering *** analysis confirms the superiority on broad bandwidth of 48 nm and robust splitting against dimensional errors of 20 *** further propose a topological interferometer for on-chip distance measurement,which also exhibits robustness against dimensional *** extension of topological principles to the fields of interferometers,may open up new possibilities for constructing robust wavelength division multiplexing,temperature-drift-insensitive sensing,and optical coherence tomography applications.

关键词： topological splitting insensitive

BIO-inspired intelligent navigation: from methodology, system theory, to behavioural science

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Science China(Information Sciences) 2024年第9期67卷 333-335页

作者： wenshuo LI Xin LIU Pengwei HU jian YANG Xiang YU Lei guo Hangzhou Innovation Institute of Beihang University School of Automation Science and Electrical Engineering Beihang University School of Instrumentation and Optoelectronic Engineering Beihang University

It is crucial for unmanned systems to determine their motion information accurately, reliably, and in real time. This function is accomplished by the autonomous navigation module of the unmanned systems. By analogy to the animals,the autonomous navigation module can be regarded as the“sensory nerve center” of an unmanned system.

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教师培训流动空间:内涵、构成和建设路径

教师教育研究 2023年第1期35卷 35-40,55页

作者：国建文郭绒教育部普通高校人文社会科学重点研究基地北京师范大学教师教育研究中心北京100875

流动空间逐渐成为网络化社会中具有主导性的空间存在,但教师教育领域仍然缺乏对教师培训流动空间的全面认识和研究。本研究依循空间社会学理论、流动空间理论建构教师培训流动空间的内涵,探究教师培训流动空间的基本构成要素,认为其由... 详细信息

流动空间逐渐成为网络化社会中具有主导性的空间存在,但教师教育领域仍然缺乏对教师培训流动空间的全面认识和研究。本研究依循空间社会学理论、流动空间理论建构教师培训流动空间的内涵,探究教师培训流动空间的基本构成要素,认为其由信息技术支撑的基础设施,教师培训机构及其所关联的在地培训资源构成的节点与核心,以及培训管理组织三大物质层次构成。若要有序建设教师培训流动空间,需要搭建由信息技术支撑的汇通式基础设施,装备共享式的节点与核心,走向精英领导、多元主体平等参与的教师培训管理实践。

关键词：教师培训流动空间数字化

Magnetic Fields Reduce Apoptosis by Suppressing Phase Separation of Tau-441

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Research 2024年第1期2023卷 181-197页

作者： wen-Juan Lin wen-Pu Shi Wan-Yi Ge Liang-Liang Chen Wei-Hong guo Peng Shang Da-Chuan Yin Key Laboratory for Space Bioscience and Biotechnology School of Life SciencesNorthwestern Polytechnical University127 Youyixi RoadXi'an 710072ShaanxiPR China

The biological effects of magnetic fields(MFs)have been a controversial ***,in recent years,there has been increasing evidence that MFs do affect biological ***,the physical mechanism remains ***,we show that MFs(16 T)reduce apoptosis in cell lines by inhibiting liquid–liquid phase separation(LLPS)of Tau-441,suggesting that the MF effect on LLPS may be one of the mechanisms for understanding the“mysterious”magnetobiological *** LLPS of Tau-441 occurred in the cytoplasm after induction with *** phase-separated droplets of Tau-441 recruited hexokinase(HK),resulting in a decrease in the amount of free HK in the *** cells,HK and Bax compete to bind to the voltage-dependent anion channel(VDAC I)on the mitochondrial membrane.A decrease in the number of free HK molecules increased the chance of Bax binding to VDAC I,leading to increased Bax-mediated *** the presence of a static MF,LLPS was marked inhibited and HK recruitment was reduced,resulting in an increased probability of HK binding to VDAC I and a decreased probability of Bax binding to VDAC I,thus reducing Bax-mediated *** findings revealed a new physical mechanism for understanding magnetobiological effects from the perspective of *** addition,these results show the potential applications of physical environments,such as MFs in this study,in the treatment of LLPS-related diseases.

关键词： inhibited Apoptosis finding

Axial enantiomers with donor-regulated TADF feature for multicolor circularly polarized electroluminescence

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Science China Chemistry 2024年第6期67卷 2039-2045页

作者： Chen-Hao guo wen-Long Zhao Ke-Ke Tan Wei-Chen guo Liheng Feng Chuan-Feng Chen Meng Li School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan030006China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

This study optimized the TADF feature of axial chiral enantiomers through precise donor engineering,and multicolor CP-TADFwas achieved in the axial chiral *** pairs of axial enantiomers with donor-regulated TADF feature,namely(R/S)-TPCBD,(R/S)-DPCBD,and(R/S)-DPACBD,were synthesized by introducing carbazole donors with different substituents onto biphenyl cyanide *** the electron-donating ability of donors increases,the emission of these axial enantiomers ranges from 455,476 to 552 nm,their singlet-triplet energy gaps(ΔE_(ST))gradually decrease from 0.30,0.22 to 0.02 e V,accompanied by an increasement in the transition rate(k_(RISC))of RISC process,and the k_(RISC)of DPACBD could reach up to 7.16×10^(5)s^(-1).These axial enantiomers also exhibit mirror-image CD and circularly polarized luminescence(CPL)***,OLEDs based on TPCBD,DPCBD,and DPACBD as emitter were then fabricated,which displayed blue,green,and orange electroluminescence with EQE_(max)of 13.0%,16.4%,and 25.0%,*** results also exhibited a phenomenon of device efficiency increasing with the enhancement of donor ***,the CP-OLEDs using(R/S)-TPCBD,(R/S)-DPCBD and(R/S)-DPACBD as emitters displayed intense CPEL signals with g_(EL)values of 3.4×10^(-3)/-4.1×10^(-3),3.2×10^(-3)/-3.1×10^(-3)and2.3×10^(-3)/-2.1×10^(-3),*** convenient molecular engineering of donor regulation in the same molecular skeleton,CP-TADF materials with multicolor CPEL and improved device performance could be conveniently achieved.

关键词： axial chirality thermally activated delayed fluorescence circularly polarized luminescence electroluminescence organic light-emitting diodes