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Cr-catalyzed allylic C(sp^(3))–H addition to aldehydes enabled by photoinduced ligand-to-metal charge transfer

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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

Review on birefringence in borates based on birefringence-active functional groups and arrangements

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Science China Chemistry 2024年第7期67卷 2155-2170页

作者： Qianzhen Zhang Ran An Zhihua Yang Xifa Long Shilie Pan Yun Yang Research Center for Crystal Materials State Key Laboratory of Functional Materials and Devices for Special Environmental ConditionsXinjiang Key Laboratory of Functional Crystal MaterialsThe Xinjiang Technical Institute of Physics&ChemistryChinese Academy of SciencesUrumqi 830011China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

As a fundamental parameter of the optical crystals,birefringence plays a vital role in many optical applications,such as phase modulation,light splitting,and polarization,especially the phase matching process of the nonlinear optical *** big birefringence not only benefits to the miniaturization of related devices,but also broadens the phase-matching wavelength range of nonlinear optical *** design and synthesis of crystals with large birefringence becomes a hot research topic due to its more and more important applications in the optical modulation and laser technology ***,crystals with birefringence greater than 0.05 in the borate system are reviewed and classified according to different birefringent active groups,and the relationship between structure and properties is thoroughly *** is hoped that this review will provide a clear understanding of what kinds of building units and arrangements would have more opportunity to get adequate birefringence in borate systems and provide the statistical references to encourage the emergence of better crystal materials with large birefringence.

关键词： birefringence borate optical functional crystal structural anisotropy arrangement of functional units

Damping capacity of Fe_(83)Ga_(17) magnetostrictive alloy under magnetic field

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Rare Metals 2024年第1期43卷 402-409页

作者： Shao-Wen Yan Xing Mu Bing-Jie Liu Li-Hong Xu Shi-Hai Guo Yan Qi Hong-Ping Zhang department of functional Material Research Central Iron and Steel Research InstituteBeijing 100081China

The damping performance of Fe_(83)Ga_(17) alloys has been investigated in the static magnetic field (H). The results demonstrate that the damping peak value can be adjusted between 0.020 and 0.085 under the magnetic f... 详细信息

关键词： alloy magnetic alloys

Carbonic anhydrase-like enzymes in the formation of Lycopodium alkaloid

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Chinese Journal of Natural Medicines 2024年第3期22卷 193-194页

作者： DONG Huiwen GE Huiming State key Laboratory of Pharmaceutical Biotechnology Institute of Functional BiomoleculesSchool of Life SciencesNanjing UniversityNanjing 210023China

Plant alkaloids,renowned for their structural diversity and bioactivity,are prominent in both modern and traditional medicine[1].Unraveling the intricacies of plant alkaloid biosynthesis could pave the way for the discovery of new natural products and *** may also shed light on the roles of existing pathways in host biology and provide valuable tools for metabolic engineering in plants and microbes[2].Unlike other major classes of plant natural products,such as terpenoids and polyketides,the formation of alkaloid scaffolds does not conform to a uniform chemical theme or depend on a singular enzyme class[3].A case in point is the Lycopodium alkaloids in the Lycopodiaceae family,where the enzymes responsible for their core scaffold construction remain unidentified[4].

关键词： Lycopodium alkaloid Carbonic anhydrase-like enzymes Biosynthesis

Rationally construction of atomic-precise interfacial charge transfer channel and strong build-in electric field in nanocluster-based Zscheme heterojunctions with enhanced photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 5002-5010页

作者： Qingtao Zhu Honglei Shen Chao Han Liu Huang Yanting Zhou Yuanxin Du Xi Kang Manzhou Zhu department of Materials Science and Engineering Centre for Atomic Engineering of Advanced MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationKey Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui UniversityHefei 230601China

The lack of effective charge transfer driving force and channel limits the electron directional migration in nanoclusters(NC)-based heterostructures,resulting in poor photocatalytic ***,a Z-scheme NC-based heterojunction(Pt1Ag28-BTT/CoP,BTT=1,3,5-benzenetrithiol)with strong internal electric field is constructed via interfacial Co-S bond,which exhibits an absolutely superiority in photocatalytic performance with 24.89 mmol·h^(−1)·g−1 H_(2)production rate,25.77%apparent quantum yield at 420 nm,and~100%activity retention in stability,compared with Pt1Ag28-BDT/CoP(BDT=1,3-benzenedithiol),Ag29-BDT/CoP,and *** enhanced catalytic performance is contributed by the dual modulation strategy of inner core and outer shell of NC,wherein,the center Pt single atom doping regulates the band structure of NC to match well with CoP,builds internal electric field,and then drives photogenerated electrons steering;the accurate surface S modification promotes the formation of Co-S atomic-precise interface channel for further high-efficient Z-scheme charge directional *** work opens a new avenue for designing NC-based heterojunction with matchable band structure and valid interfacial charge transfer.

关键词： atomically precise metal nanocluster Z-scheme heterojunction interfacial charge transfer build-in electric field photocatalytic hydrogen production

Metal complex catalysts broaden bioorthogonal reactions

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Science China Chemistry 2024年第2期67卷 428-449页

作者： Hanjie Zhang Xiaoyu Qin Junping Wang Li Ma Tianfeng Chen department of Chemistry Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou510632China

Bioorthogonal reactions involving transition metals have diversified applications in imaging,drug development,chemical catalysis and other *** metals used to catalyze the bioorthogonal reaction mainly include ruthenium,palladium,copper,and ***,the great potential for translational applications of bioorthogonal reaction needs to be further expanded and their reaction efficiency should be ***,it is an urgent need for the development of this field to find more suitable catalysts to efficiently catalyze existing biological orthogonal reactions and expand the types of biological orthogonal ***,this review not only summarizes those transition metal complexes-based catalysts participating in bioorthogonal reaction and some bioorthogonal reactions involving transition metals inside the cells,but also sheds light into the discovery of new transition metal complexes and their future development in applications.

关键词： transition metal complexes bioorthogonal reactions biological applications

DLP printing of BT/HA nanocomposite ceramic scaffolds using low refractive index BT crystals

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Journal of Materiomics 2024年第5期10卷 1036-1048页

作者： Ruixuan Xue Peimei Yuan Bo Zhao Fei Jing Xuyuan Kou Wangyang Yue Yan wang Dongmei Wang Galhenage Asha Sewvandi Dengwei Hu Faculty of Chemistry and Chemical Engineering Baoji University of Arts and SciencesKey Laboratory of Functional Materials of Baoji Engineering Research Center for Titanium Based Functional Materials and DevicesUniversities of Shaanxi Province1 Hi-Tech AvenueBaoji721013ShaanxiChina department of Materials Science and Engineering Faculty of EngineeringUniversity of MoratuwaKatubeddaSri Lanka

Biological piezoelectric materials have significant potential for bone repair and energy harvesting owing to their excellent biocompatibility and piezoelectric *** BaTiO3/Ca10(PO4)6(OH)2(BT/HA)composite material is an outstanding representative of biological piezoelectric materials,which has not been individually designed using digital light processing(DLP)3D printing because of the large difference in the refractive index of its ***,in this work,double-sided-tooth plate-like BT crystals with high curvature were prepared via a hydrothermal process,and BT/HA ceramic slurries were grinded out using dispersed intermittent ball milling scheme,and BT/HA nanocomposite ceramic scaffolds were fabricated by DLP 3D printing *** nanostructure,dielectric properties,and piezoelectric energy harvesting performance of the BT/HA nanocomposite ceramic scaffolds were *** influences of different morphologies and contents for BT on the piezoelectric potential and stress distribution were analyzed based on a multi-physics coupling finite element *** cell proliferation and adhesion abilities were investigated *** BT/HA nanocomposite ceramic scaffolds present excellent dielectric properties,cell proliferation and adhesion abilities,and an open circuit voltage of 8 V during piezoelectric energy *** material properties and multi-physics coupling finite element analysis imply that the double-sided-tooth plate-like BT plays an important role for the fastness structure and electric field distribution in the BT/HA ***,this work provides a strategy for the application of the customized BT/HA nanocomposite ceramic scaffolds in new-generation orthopedic implants and biological energy harvesting.

关键词： 3D printing BT/HA nanocomposite ceramics Bio-piezoelectric scaffolds Energy harvesting

Anisotropic Plasmon Resonance Enables Spatially Controlled Photothermal and Photochemical Effects in Hot Carrier-Driven Catalysis

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Chinese Journal of Chemistry 2024年第16期42卷 1877-1885页

作者： Jiaqi Wang Zhijie Zhu Kai Feng Shuang Liu Yuxuan Zhou Ifra Urooj Jiari He Zhiyi Wu Jiahui Shen Xu Hu Zhijie Chen Xudong Dong Manzar Sohail Yanyun Ma Jinxing Chen Chaoran Li Xingda An Le He Institute of functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhouJiangsu 215123China Jiangsu Key Laboratory ofAdvanced Negative Carbon Technologies Soochow UniversitySuzhouJiangsu 215123China Jiangsu Key Laboratory for Carbon-Based functional Materials&Devices Soochow UniversitySuzhouJiangsu 215123China department of Chemistry School of Natural SciencesNational University of Sciences and TechnologyIslamabad 44000Pakistan

Localized surface plasmon resonance has been demonstrated to provide effective photophysical enhancement mechanisms in plasmonic ***,it remains highly challenging for distinct mechanisms to function in synergy for a collective gain in catalysis due to the lack of spatiotemporal control of their ***,the anisotropic plasmon resonance nature of Au nanorods was exploited to achieve distinct functionality towards synergistic *** and photochemical effects were enabled by the longitudinal and transverse plasmon resonance modes,respectively,and were enhanced by partial coating of silica nanoshells and epitaxial growth of a reactor *** excitation leads to a synergistic gain in photothermal-mediated hot carrier-driven hydrogen evolution *** approach provides important design principles for plasmonic photocatalysts in achieving spatiotemporal modulation of distinct photophysical enhancement *** also effectively broadens the sunlight response range and increases the efficacy of distinct plasmonic enhancement pathways towards solar energy harvesting and conversion.

关键词： Plasmon resonance Photothermal effect Photochemistry Photocatalysis Metal nanoparticles Charge carrier injection Heterogeneous catalysis Photoelectrochemistry

Theta Oscillations Support Prefrontal-hippocampal Interactions in Sequential Working Memory

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Neuroscience Bulletin 2024年第2期40卷 147-156页

作者： Minghong Su Kejia Hu Wei Liu Yunhao Wu Tao Wang Chunyan Cao Bomin Sun Shikun Zhan Zheng Ye Institute of Psychology Chinese Academy of SciencesBeijing 100101China department of Psychology University of Chinese Academy of SciencesBeijing 100049China department of Neurosurgery Center for Functional NeurosurgeryRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Institute of Neuroscience Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China

The prefrontal cortex and hippocampus may support sequential working memory beyond episodic memory and spatial *** stereoelectroencephalography(SEEG)study investigated how the dorsolateral prefrontal cortex(DLPFC)interacts with the hippocampus in the online processing of sequential *** patients with epilepsy(eight women,age 27.6±8.2 years)completed a line ordering task with SEEG recordings over the DLPFC and the *** showed longer thinking times and more recall errors when asked to arrange random lines clockwise(random trials)than to maintain ordered lines(ordered trials)before recalling the orientation of a particular ***,the ordering-related increase in thinking time and recall error was associated with a transient theta power increase in the hippocampus and a sustained theta power increase in the DLPFC(3–10 Hz).In particular,the hippocampal theta power increase correlated with the memory precision of line ***,theta phase coherences between the DLPFC and hippocampus were enhanced for ordering,especially for more precisely memorized ***,the theta band DLPFC→hippocampus influence was selectively enhanced for ordering,especially for more precisely memorized *** study suggests that theta oscillations may support DLPFC-hippocampal interactions in the online processing of sequential information.

关键词： Sequential working memory Hippocampus Dorsolateral prefrontal cortex Theta oscillations Stereoelectroencephalography(SEEG) Phase coherence Granger causality