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Journal of Environmental Sciences 2024年第3期137卷 224-236页

作者： Zhexin Zhu Wenjie Qian Zhiguo Shang Xiaoji Ma Zhendong Wang Wangyang Lu Wenxing Chen national Engineering lab for Textile Fiber Materials and Processing Technology(Zhejiang) Zhejiang Sci-Tech UniversityHangzhou 310018China

The monoaminotrinitro iron phthalocyanine(FeMATNPc)is used to connect with isonicotinic acid(INA)for amide bonding and axial coordination to synthetic a unique catalyst FeMATNPc-INA,which is loaded in polyacrylonitrile(PAN)nanofibers by electrospinning.The introduction of INA destroys theπ-πconjugated stack structure in phthalocyanine molecules and exposes more active sites.The FeMATNPc-INA structure is characterized by X-ray photoelectron spectroscopy and UV-visible absorption spectrum,and the FeMATNPcINA/PAN structure is characterized by Fourier transform infrared spectroscopy and X-ray diffraction.The FeMATNPc-INA/PAN can effectively activate peroxymonosulfate(PMS)to eliminate carbamazepine(CBZ)within 40 minutes(PMS 1.5 mmol/L)in the dark.The effects of catalyst dosage,PMS concentration,pH and inorganic anion on the degradation of CBZ are investigated.It has been confirmed by electron paramagnetic resonance,gas chromatography–mass spectroscopy and free radical capture experiments that the catalytic system is degraded by·OH,SO4^(·-)and Fe(IV)=O are the major active species,the singlet oxygen(^(1)O_(2))is the secondary active species.The degradation process of CBZ is analyzed by ultra-high performance liquid chromatography-mass spectrometry and the aromatic compounds have been degraded to small molecular acids.

关键词： Pyridine bridged iron phthalocyanine Isonicotinic chloride hydrochloride Efficient elimination Peroxymonosulfate activation Degradation pathway

40-meter-long REBCO tapes with critical current over 4,000 A/12 mm at 4.2 K and 13 T by advanced MOCVD

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superconductivity 2024年第1期9卷 29-34页

作者： Mahesh Paidpilli Chirag Goel Bhabesh Sarangi Siwei Chen Eduard Galstyan Jan Jaroszynski Griffin Bradford Dmytro Abraimov Venkat Selvamanickam Department of Mechanical Engineering Advanced Manufacturing InstituteTexas Center for SuperconductivityUniversity of HoustonHoustonTexasUSA AMPeers LLC HoustonTexasUSA national High Magnetic Field laboratory TallahasseeFloridaUSA

REBa_(2)Cu_(3)O_(7−δ)(REBCO,RE=rare earth)tapes doped with 5%and 15%Zr have been scaled up to lengths more than 40 m in a pilot‐scale advanced metal organic chemical vapor deposition(A‐MOCVD)tool.The precursor compositions used for the long tapes were guided by a study of the influence of(Ba+dopant)/Cu content on the critical current density(Jc)of 5 and 15 mol.%Hf‐and Zr‐added tapes at 4.2 K and 13 T.The 40‐mlong tapes exhibited a critical current(Ic)over 4,000 A/12 mm at 4.2 K and 13 T as well as over 1,400 A/12 mm at 20 K and 20 T.The critical current densities of a 40‐m‐long tape doped with 5%Zr at 4.2 K measured at the national High Magnetic Field laboratory(NHMFL)were>10 MAcm^(−2)and>5 MAcm^(−2)at 14 T and 30 T,respectively,which are over three times those of commercial REBCO tapes.The infield Jc of 5%Zradded 40‐m‐long tapes was similar to those of previously‐reported high‐performance short samples made with 15%Zr or Hf.These results demonstrate the excellent potential of A‐MOCVD for manufacturing high Ic REBCO tapes for use in ultrahigh‐field magnet applications.

关键词： High‐temperature superconductors MOCVD REBCO Critical current

Negligible normal fluid in superconducting state of heavily overdoped Bi2Sr2CaCu2O8+δ detected by ultra-low temperature angle-resolved photoemission spectroscopy

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Chinese Physics B 2024年第7期 572-578页

作者：殷超辉汪清泓解于洋陈逸雯刘俊豪杨鉴刚贾俊杰张杏吕文凯闫宏涛戎洪涛张申金王志敏宗楠刘丽娟李如康王晓洋张丰丰杨峰彭钦军许祖彦刘国东毛寒青赵林李昕彤周兴江 national laboratory for superconductivity Beijing National Laboratory for Condensed Matter PhysicsInstitute of Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Technical Institute of Physics and Chemistry Chinese Academy of Sciences Songshan Lake Materials laboratory

In high temperature cuprate superconductors,it was found that the superfluid density decreases with the increase of hole doping.One natural question is whether there exists normal fluid in the superconducting state in the overdoped region.In this paper,we have carried out high-resolution ultra-low temperature laser-based angle-resolved photoemission measurements on a heavily overdoped Bi2212 sample with a Tcof 48 K.We find that this heavily overdoped Bi2212 remains in the strong coupling regime with 2Δ0/（kBTc）=5.8.The single-particle scattering rate is very small along the nodal direction（～5 meV） and increases as the momentum moves from the nodal to the antinodal regions.A hard superconducting gap opening is observed near the antinodal region with the spectral weight at the Fermi level fully suppressed to zero.The normal fluid is found to be negligibly small in the superconducting state of this heavily overdoped Bi2212.These results provide key information to understand the high Tcmechanism in the cuprate superconductors.

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Absence of BCS–BEC crossover in FeSe0.45Te0.55 superconductor

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Chinese Physics B 2024年第7期 89-96页

作者：贾俊杰谷亚东殷超辉束英杰陈逸雯史聚民张杏陈浩苗泰民任晓琳梁波朱文培蔡能张丰丰张申金杨峰王志敏彭钦军许祖彦毛寒青刘国东任治安赵林周兴江 national laboratory for superconductivity Beijing National Laboratory for Condensed Matter PhysicsInstitute of Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Technical Institute of Physics and Chemistry Chinese Academy of Sciences Songshan Lake Materials laboratory

In iron-based superconductor Fe（Se,Te）, a flat band-like feature near the Fermi level was observed around the Brillouin zone center in the superconducting state. It is under debate whether this is the evidence on the presence of the BCS–BEC[Bardeen–Cooper–Schrieffer（BCS）, Bose–Einstein condensation（BEC）] crossover in the superconductor. High-resolution laser-based angle-resolved photoemission measurements are carried out on high quality single crystals of FeSe0.45Te0.55superconductor to address the issue. By employing different polarization geometries, we have resolved and isolated the dyz band and the topological surface band, making it possible to study their superconducting behaviors separately. The dyz band alone does not form a flat band-like feature in the superconducting state and the measured dispersion can be well described by the BCS picture. We find that the flat band-like feature is formed from the combination of the dyz band and the topological surface state band in the superconducting state. These results reveal the origin of the flat band-like feature and rule out the presence of BCS-BEC crossover in Fe（Se,Te） superconductor.

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Co-doped BaFe_(2)As_(2) Josephson junction fabricated with a focused helium ion beam

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Chinese Physics B 2024年第4期33卷 181-186页

作者：陈紫雯张焱马平徐中堂李宇龙王越路建明马衍伟甘子钊 Applied superconductivity Research Center Peking UniversityBeijing 100871China State Key laboratory for Artificial Microstructure and Mesoscopic Physics Peking UniversityBeijing 100871China Institute of Condensed Matter Physics School of PhysicsPeking UniversityBeijing 100871China Yangtze Delta Institute of Optoelectronics Peking UniversityBeijing 100871China Key laboratory of Applied superconductivity Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China

Josephson junction plays a key role not only in studying the basic physics of unconventional iron-based superconductors but also in realizing practical application of thin-film based devices,therefore the preparation of high-quality iron pnictide Josephson junctions is of great importance.In this work,we have successfully fabricated Josephson junctions from Co-doped BaFe_(2)As_(2)thin films using a direct junction fabrication technique which utilizes high energy focused helium ion beam(FHIB).The electrical transport properties were investigated for junctions fabricated with various He^(+)irradiation doses.The junctions show sharp superconducting transition around 24 K with a narrow transition width of 2.5 K,and a dose correlated foot-structure resistance which corresponds to the effective tuning of junction properties by He^(+)irradiation.Significant J_c suppression by more than two orders of magnitude can be achieved by increasing the He^(+)irradiation dose,which is advantageous for the realization of low noise ion pnictide thin film devices.Clear Shapiro steps are observed under 10 GHz microwave irradiation.The above results demonstrate the successful fabrication of high quality and controllable Co-doped BaFe_(2)As_(2)Josephson junction with high reproducibility using the FHIB technique,laying the foundation for future investigating the mechanism of iron-based superconductors,and also the further implementation in various superconducting electronic devices.

关键词： focused helium ion beam Co doped BaFe_(2)As_(2) Josephson junction

Deer antler stem cell niche: An interesting perspective

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World Journal of Stem Cells 2024年第5期16卷 479-485页

作者： Claudia Cavallini Elena Olivi Riccardo Tassinari Chiara Zannini Gregorio Ragazzini Martina Marcuzzi Valentina Taglioli Carlo Ventura national laboratory of Molecular Biology and Stem Cell Engineering National Institute of Biostructures and Biosystems-Eldor LabBologna 40128Italy Eldor lab Bologna 40128Italy Department of Medical and Surgical Sciences(DIMEC) University of BolognaBologna 40138Italy

In recent years,there has been considerable exploration into methods aimed at enhancing the regenerative capacity of transplanted and/or tissue-resident cells.Biomaterials,in particular,have garnered significant interest for their potential to serve as natural scaffolds for cells.In this editorial,we provide commentary on the study by Wang et al,in a recently published issue of World J Stem Cells,which investigates the use of a decellularized xenogeneic extracellular matrix(ECM)derived from antler stem cells for repairing osteochondral defects in rat knee joints.Our focus lies specifically on the crucial role of biological scaffolds as a strategy for augmenting stem cell potential and regenerative capabilities,thanks to the establishment of a favorable microenvironment(niche).Stem cell differen-tiation heavily depends on exposure to intrinsic properties of the ECM,including its chemical and protein composition,as well as the mechanical forces it can generate.Collectively,these physicochemical cues contribute to a bio-instructive signaling environment that offers tissue-specific guidance for achieving effective repair and regeneration.The interest in mechanobiology,often conceptualized as a form of“structural memory”,is steadily gaining more validation and momen-tum,especially in light of findings such as these.

关键词： Extracellular matrix Antler stem cells Stem cell niche Regenerative medicine Decellularized scaffolds Cell memory

Analysis of photocatalytic degradation of polyamide microplastics in metal salt solution by high resolution mass spectrometry

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Journal of Environmental Sciences 2024年第5期139卷 473-482页

作者： Yunjin Zhong Lebing Zhuo Wangyang Lu national Engineering lab for Textile Fiber Materials&Processing Technology(Zhejiang) School of Materials Science&EngineeringZhejiang Sci-Tech UniversityHangzhou 310018China

Microplastic pollution has become one of the most concerned focuses in the world.Among many treatment methods,photocatalysis is considered to be one of the most environmentally friendly methods.In this work,the photodegradation behavior of polyamide microplastics is studied by using polyamide 6(PA6)as model microplastics and FeCl_(3) as catalyst.It is hoped that the PA6 fiber can be effectively degraded by utilizing the strong oxidizing active species that can be produced after FeCl_(3) is irradiated in water.The results shows that PA6 fiber can be almost completely degraded after 10 days of irradiation in FeCl_(3) aqueous solution,indicating that it is promising to use this new method to solve the problem of PA6type microplastics.In addition,the chain scission mechanism and degradation process of PA6 are analyzed in detail by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS),which provides a new insight for the study of polymer degradation mechanism.

关键词： FeCl_(3) Photocatalysis Polyamide 6 Chain scission

Astronomical Knowledge Entity Extraction in Astrophysics Journal Articles via Large Language Models

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Research in Astronomy and Astrophysics 2024年第6期24卷 142-157页

作者： Wujun Shao Rui Zhang Pengli Ji Dongwei Fan Yaohua Hu Xiaoran Yan Chenzhou Cui Yihan Tao Linying Mi Lang Chen national Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences national Astronomical Data Center Research Institute of Artificial Intelligence Zhejiang Lab Guilin University Xidian University

Astronomical knowledge entities, such as celestial object identifiers, are crucial for literature retrieval and knowledge graph construction, and other research and applications in the field of astronomy. Traditional methods of extracting knowledge entities from texts face numerous challenging obstacles that are difficult to overcome.Consequently, there is a pressing need for improved methods to efficiently extract them. This study explores the potential of pre-trained Large Language Models(LLMs) to perform astronomical knowledge entity extraction(KEE) task from astrophysical journal articles using prompts. We propose a prompting strategy called PromptKEE, which includes five prompt elements, and design eight combination prompts based on them. We select four representative LLMs(Llama-2-70B, GPT-3.5, GPT-4, and Claude 2) and attempt to extract the most typical astronomical knowledge entities, celestial object identifiers and telescope names, from astronomical journal articles using these eight combination prompts. To accommodate their token limitations, we construct two data sets: the full texts and paragraph collections of 30 articles. Leveraging the eight prompts, we test on full texts with GPT-4and Claude 2, on paragraph collections with all LLMs. The experimental results demonstrate that pre-trained LLMs show significant potential in performing KEE tasks, but their performance varies on the two data sets. Furthermore,we analyze some important factors that influence the performance of LLMs in entity extraction and provide insights for future KEE tasks in astrophysical articles using LLMs. Finally, compared to other methods of KEE,LLMs exhibit strong competitiveness in multiple aspects.

关键词： astronomical databases: miscellaneous methods: data analysis virtual observatory tools

Stereoselective recognition of morphine enantiomers by μ-opioid receptor

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national Science Review 2024年第3期11卷 183-191页

作者： Yibo Wang Van A.Ngo Xiaohui Wang laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of Sciences Advanced Computing for Life Sciences and Engineering Group Science Engagement Section National Center for Computational Sciences Oak Ridge National Lab School of Applied Chemistry and Engineering University of Science and Technology of China Beijing national laboratory for Molecular Sciences

Stereospecific recognition of chiral molecules plays a crucial role in biological systems. The μ-opioid receptor（MOR） exhibits binding affinity towards（-）-morphine, a well-established gold standard in pain management, while it shows minimal binding affinity for the（+）-morphine enantiomer, resulting in a lack of analgesic activity. Understanding how MOR stereoselectively recognizes morphine enantiomers has remained a puzzle in neuroscience and pharmacology for over half-a-century due to the lack of direct observation techniques. To unravel this mystery, we constructed the binding and unbinding processes of morphine enantiomers with MOR via molecular dynamics simulations to investigate the thermodynamics and kinetics governing MOR's stereoselective recognition of morphine enantiomers. Our findings reveal that the binding of（-）-morphine stabilizes MOR in its activated state, exhibiting a deep energy well and a prolonged residence time. In contrast,（+）-morphine fails to sustain the activation state of MOR.Furthermore, the results suggest that specific residues, namely D1142.50and D1473.32, are deprotonated in the active state of MOR bound to（-）-morphine. This work highlights that the selectivity in molecular recognition goes beyond binding affinities, extending into the realm of residence time.

关键词： stereoselective recognition thermodynamics and kinetics residence time morphine enantiomers μ-opioid receptor

Revolutionary entrapment model of uniformly distributed swarm robots in morphogenetic formation

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Defence Technology（防务技术） 2024年第1期31卷 496-509页

作者： Chen Wang Zhaohui Shi Minqiang Gu Weicheng Luo Xiaomin Zhu Zhun Fan Shantou University ShantouGuangdongChina national University of Defense Technology ChangshaChina Key lab of Digital Signal and Image Processing of Guangdong Province China

This study proposes a method for uniformly revolving swarm robots to entrap multiple targets,which is based on a gene regulatory network,an adaptive decision mechanism,and an improved Vicsek-model.Using the gene regulatory network method,the robots can generate entrapping patterns according to the environmental input,including the positions of the targets and obstacles.Next,an adaptive decision mechanism is proposed,allowing each robot to choose the most well-adapted capture point on the pattern,based on its environment.The robots employ an improved Vicsek-model to maneuver to the planned capture point smoothly,without colliding with other robots or obstacles.The proposed decision mechanism,combined with the improved Vicsek-model,can form a uniform entrapment shape and create a revolving effect around targets while entrapping them.This study also enables swarm robots,with an adaptive pattern formation,to entrap multiple targets in complex environments.Swarm robots can be deployed in the military field of unmanned aerial vehicles’(UAVs)entrapping multiple targets.Simulation experiments demonstrate the feasibility and superiority of the proposed gene regulatory network method.

关键词： Swarm intelligence Revolutionary entrapment Flocking Robots Gene regulatory network Vicsek-model Entrapping multiple targets