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Chinese Journal of Chemistry 2024年第9期42卷 963-972页

作者： Haoran Zhang JiaojiaoQin Xiaoyan Tang Beijing National Laboratoryfor Molecular sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenterforSoftMatter Science and EngineeringCollegeof Chemistry andMolecularEngineeringPeking UniversityBeijing 100871China

Poly(3-hydroxybutyrate),a crucial member of the large biodegradable polyhydroxyalkanoate family,suffers from its brittleness.To enhance its performance,we employed a straightforward approach involving the ring-opening copolymerization of racemic-β-butyrolactone(rac-β-BL)andβ-propiolactone(β-PL)using the syndio-selective amino-alkoxy-bis(phenolate)-yttrium complex as a catalyst,thanks to the excellent ductility of poly(3-hydroxypropionate).Control over the rac-β-BL/β-PL feeding ratios and polymerization time yielded random or block copolymers with tunable thermal and mechanical properties comparable to traditional fossil-based plastics.Furthermore,we achieved one-pot synthesis of hard-soft-hard triblock copolymers by exploiting monomers’different copolymerization rates and a bifunctional initiator,thus transforming polyhydroxyalkanoates from hard and tough plastics to soft and ductile thermoplastic elastomers.

关键词： Ring-opening(co-)polymerization Biodegradable polymers Polyhydroxyalkanoates Copolymers Plastics Elastomers

Recent Advances in Deuteration Reactions

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Chinese Journal of Chemistry 2024年第10期42卷 1145-1156页

作者： Hao Li Muhammad Shabbir Wu Li Aiwen Lei Institutefor Advanced Studies(IAS) Collegeof Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China

The deuteration of organic compounds has attracted more attentions in recent years for the potential applications in new drug discovery and synthetic chemistry.For this purpose,many efficient deuterium labeling methodologies have been developed,including hydrogen isotope exchange(HIE),reductive deuteration,and dehalogenative deuteration that allow for the synthesis of selectively deuterated compounds.In the last few years,great breakthroughs in selective isotope labeling have been achieved and the interest in new methodologies for the deuteration of organic molecules is rising.In this review,we summarized the recent developments in the selective deuteration of organic molecules since 2021.Several types of key processes in deuterium incorporation reactions,including H/D exchange,reductive deuteration and dehalogenative deuteration,are introduced and discussed.

关键词： Deuterated compounds H/D exchange Reductive deuterations Dehalogenative deuterations Deuterium C-Hactivation Synthetic methods

Systems science in the new era: intelligent systems and big data

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science China(Information sciences) 2024年第3期67卷 308-310页

作者： Wenwu YU Duxin CHEN Hongzhe LIU He WANG Jinde CAO Zengru DI Xiaojun DUAN Bin JIA Xiaodong DING Yiguang HONG School of Mathematics Southeast University Purple Mountain Laboratories International Academic Center of Complex Systems Beijing Normal University College of science National University of Defense Technology School of Systems science Beijing Jiaotong University Business School University of Shanghai for Science and Technology Department of Control science and Engineering Tongji University

This study introduces the emergence, research challenges,and future development of intelligent systems and big data(ISBD) and discusses the significance of ISBD to systems science. To this end, an overview of systems science is first presented, followed by the conclusion that the development of artificial intelligence(AI) has promoted the derivation and development of intelligent systems(ISs).

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Topological magnetoelectric response in ferromagnetic axion insulators

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National science Review 2024年第2期11卷 8-14页

作者： Yuhao Wan Jiayu Li Qihang Liu Department of Physics and Shenzhen Institute for Quantum science and Engineering(SIQSE) Southern University of Science and Technology Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and Technology Guangdong Provincial Key Laboratory for Computational science and Material Design Southern University of Science and Technology

The topological magnetoelectric effect （TME） is a hallmark response of the topological field theory,which provides a paradigm shift in the study of emergent topological phenomena.However,its direct observation is yet to be realized due to the demanding magnetic configuration required to gap all surface states.Here,we theoretically propose that axion insulators with a simple ferromagnetic configuration,such as the MnBi2Te4/（Bi2Te3）nfamily,provide an ideal playground to realize the TME.In the designed triangular prism geometry,all the surface states are magnetically gapped.Under a vertical electric field,the surface Hall currents give rise to a nearly half-quantized orbital moment,accompanied by a gapless chiral hinge mode circulating in parallel.Thus,the orbital magnetization from the two topological origins can be easily distinguished by reversing the electric field.Our work paves the way for direct observation of the TME in realistic axion-insulator materials.

关键词： topological magnetoelectric effect axion insulator magnetic topological materials

Phytochemical analysis, antioxidant, acetylcholinesterase, and α-amylase inhibitors from Hippeastrum hybridum extract

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Journal of Traditional Chinese Medicine 2024年第3期44卷 496-504页

作者： Naila Sher Mushtaq Ahmed Nadia Mushtaq Department of Biotechnology University of Science and Technology Department of Botany University of Science and Technology

OBJECTIVE:To investigate the effects of Hippeastrum hybridum（HH） as a free radical scavenger,and an inhibitor of the two enzymes i-e Alpha-amylase（α-amylase） and acetylcholinesterase（AChE）.METHODS:In this study,HH plant was preliminary analyzed for phytochemical screening and then tested for its antioxidant,anti-α-amylase,and anti-AChE efficiency via standard procedures.RESULTS:Phytochemical analysis shows the existence of different compounds;while Coumarins and quinones were absent.The total phenolic,flavonoid,and tannins content were found to be（78.52±0.69） mg GAE/g,（2.01±0.04） mg RUE/g,and（58.12±0.23） mg TAE/g of plant extract respectively.28.02%±0.02% alkaloid and 2.02%±0.05% saponins were present in the HH extract.The HH extract showed the anti-oxidant property with IC50（50%inhibition） of（151.01±0.13）(HH),（79.01±0.04）(Ascorbic acid) for ferric reducing,（91.48±0.13）(HH),（48.02±0.11）(Ascorbic acid) against Ammonium molybdenum,（156.02±0.31）(HH),（52.38±0.21）(Ascorbic acid) against DPPH,136.01±0.21（HH）,52.02±0.31（Ascorbic acid） against H2O2,and 154.12±0.03（HH）,（40.05±0.15）(Ascorbic acid)μg/mL against ABTS respectively.Statistical analysis indicated that HH caused a competitive type of inhibition of α-amylase(Vmaxremained constant and Km increases from 10.65 to84.37%) while Glucophage caused the un-competitive type of inhibition i-e both Km and Vmaxdecreased from40.49 to 69.15%and 38.86 to 69.61%respectively.The Ki,（inhibition constant）;KI,（dissociation constant）,Km,（Michaelis-Menten constant）,and IC50 were found to be62,364,68.1,and 38.08±0.22 for HH and 12,101.05,195,34.01±0.21 for Glucophage.Similarly,HH causes an anon-competitive type of inhibition of AChE i-e Km remains constant while Vmaxdecreases from 60.5%to74.1%.The calculated Ki,KI,Km,and IC50 were found to be 32,36.2,0.05,and 18.117±0.018.CONCLUSION:From the current results,it is concluded that HH extract contains bioactive compounds,and could be a good alternative to controlling oxidants,Alzheimer‘s and Type-Ⅱ diabetic diseases.

关键词： Hippeastrum hybridum acetylcholinesterase alpha-amylase antioxidant phytochemicals

On the topological surface states of the intrinsic magnetic topological insulator Mn-Bi-Te family

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National science Review 2024年第2期11卷 50-64页

作者： Yuan Wang Xiao-Ming Ma Zhanyang Hao Yongqing Cai Hongtao Rong Fayuan Zhang Weizhao Chen Chengcheng Zhang Junhao Lin Yue Zhao Chang Liu Qihang Liu Chaoyu Chen Shenzhen Institute for Quantum science and Engineering(SIQSE)and Department of Physics Southern University of Science and Technology(SUSTech)

We review recent progress in the electronic structure study of intrinsic magnetic topological insulators（MnBi2Te4）·（Bi2Te3）n（n = 0, 1, 2, 3） family. Specifically, we focus on the ubiquitously（nearly）gapless behavior of the topological Dirac surface state observed by photoemission spectroscopy, even though a large Dirac gap is expected because of surface ferromagnetic order. The dichotomy between experiment and theory concerning this gap behavior is perhaps the most critical and puzzling question in this frontier. We discuss various proposals accounting for the lack of magnetic effect on the topological Dirac surface state, which are mainly categorized into two pictures, magnetic reconfiguration and topological surface state redistribution. Band engineering towards opening a magnetic gap of topological surface states provides great opportunities to realize quantized topological transport and axion electrodynamics at higher temperatures.

关键词： intrinsic magnetic topological insulator topological surface states magnetic gap magnetic reconfiguration topological surface state redistribution van der Waals spacing expansion

Applications and grants of the National Natural science Foundation of China's General Program and Young Scientists Fund in immunology research:a 10-year review(2013–2022)

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science China(Life sciences) 2024年第6期67卷 1321-1324页

作者： Baoman Li Yanyan Tian Puyue Wang Department of Life sciences National Natural Science Foundation of ChinaBeijing 100085China

Immunology,a biomedical discipline with an ancient history of maintaining thriving research vitality to date,refers to the study of the structure and function of the immune system of the body,the pathogenesis of immune-related diseases,immunological diagnoses,and prevention mechanisms(National Natural science Foundation of China,2023).Immunological research is the foundation of research in biology,as well as basic and clinical medicine(Kubli et al.,2021).

关键词： prevention Foundation Natural

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science map of academic misconduct

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The Innovation 2024年第2期5卷 1-2页

作者： Menghui Li Zhesi Shen National science Library Chinese Academy of SciencesBeijing 100190China

After a whistleblower exposed a large-scale fraud,there has been a surge in retractions,affecting scientific integrity and attracting extensive attention from various stakeholders.1,2 Countries,institutes,and journals are among the entities receiving special attention.3,4 However,our understanding of the actual prevalence of misconduct across disciplines and topics remains limited.Previous studies of academic misconduct have primarily focused on biomedical and life sciences,3 but have paid little attention to the broader scientific fields.

关键词： academic attracting primarily

Reinforcing oxygen electrocatalytic activity via selective dualphase heterointerface engineering for rechargeable Zn-air batteries

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Rare Metals 2024年第4期43卷 1524-1536页

作者： Chao Cheng Chuang Zhi Zhong-Ti Sun Yong-Qiang Ming Ting-Ting Xiang Qing-Chao Zhu Zi-Rui Wu Bing Li Yi Li Cheng Jin Yong Cao Juan Yang School of Materials science and Engineering Jiangsu University Faculty of Material science and Engineering Kunming University of Science and Technology

Dual-phase heterointerface electrocatalysts（DPHE） constructed by oxygen reduction reaction（ORR）-and oxygen evolution reaction（OER）-active elements exhibit excellent bifunctional activity and long-term durability due to the abundant interface exposure and synergistic catalytic effect.Herein,low-dimensional N-doped graphene nanoribbons（N-GNRs） coupling with ultrathin CoO nanocomposites（N-GNRs/CoO） were controllably fabricated through a facile two-step approach using synthesized Co（OH）2nanosheet as CoO precursor.Density functional theory（DFT） calculations and experimental characterizations prove that the formation of interface between N-GNRs and CoO can induce local charge redistribution,contributing to the improvement of catalytic activity and stability.The optimal N-GNRs/CoO DPHE possesses hierarchically porous architectures and presents outstanding bifunctional activities with a small potential gap of 0.729 V between the potential at 10 mA·cm-2for OER and the halfwave potential for ORR,which outperforms Pt/C+IrO2and the majority of noble-metal-free bifunctional catalysts.Liquid-and solid-state rechargeable Zn-air batteries assembled with N-GNRs/CoO as the cathode also display high peak power density and fantastic cycle stability,superior to that of benchmark Pt/C +IrO2catalyst.It is anticipated to offer significant benefits toward high activity,stability and mechanical flexibility bifunctional oxygen electrocatalysts for rechargeable Zn-air batteries.

关键词： Interface engineering Graphene nanoribbons CoO Bifunctional electrocatalyst Zn–air batteries

Recent Advances in Patterning Strategies for Full‑Color Perovskite Light‑Emitting Diodes

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Nano-Micro Letters 2024年第3期16卷 99-137页

作者： Gwang Heon Lee Kiwook Kim Yunho Kim Jiwoong Yang Moon Kee Choi Graduate School of Semiconductor Materials and Devices Engineering Center for Future Semiconductor Technology(FUST)Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea Department of Energy science and Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea Energy science and Engineering Research Center Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea Department of Materials science and Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea Center for Nanoparticle Research Institute for Basic Science(IBS)Seoul 08826Republic of Korea

Metal halide perovskites have emerged as promising light-emitting materials for next-generation displays owing to their remarkable material characteristics including broad color tunability,pure color emission with remarkably narrow bandwidths,high quantum yield,and solution processability.Despite recent advances have pushed the luminance efficiency of monochromic perovskite light-emitting diodes(PeLEDs)to their theoretical limits,their current fabrication using the spincoating process poses limitations for fabrication of full-color displays.To integrate PeLEDs into full-color display panels,it is crucial to pattern red–green–blue(RGB)perovskite pixels,while mitigating issues such as cross-contamination and reductions in luminous efficiency.Herein,we present state-of-the-art patterning technologies for the development of full-color PeLEDs.First,we highlight recent advances in the development of efficient PeLEDs.Second,we discuss various patterning techniques of MPHs(i.e.,photolithography,inkjet printing,electron beam lithography and laserassisted lithography,electrohydrodynamic jet printing,thermal evaporation,and transfer printing)for fabrication of RGB pixelated displays.These patterning techniques can be classified into two distinct approaches:in situ crystallization patterning using perovskite precursors and patterning of colloidal perovskite nanocrystals.This review highlights advancements and limitations in patterning techniques for PeLEDs,paving the way for integrating PeLEDs into full-color panels.

关键词： Perovskite Light-emitting diode Full-color display High-resolution patterning Electroluminescence

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