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New progress of the miniaturized microwave ion source at Peking University

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Radiation Detection Technology and Methods 2023年第4期7卷 545-549页

作者： S.X.Peng T.H.Ma W.B.Wu B.j.Cui A.L.Zhang Y.X.jiang Z.Y.Guo j.e.chen State Key Laboratory of Nuclear Physics and Technology and Institute of Heavy Ion Physics Peking UniversityBeijingChina State Key Laboratory of Particle Detection and electronics Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei230026China

The generation of plasma in a microwave ion source involves confining electrons using a static magnetic field and energizing them with an electromagnetic field that transmitted into the plasma ***,according to electromagnetics theory,there is always a cut-off size in circular wave guides for a given *** a 2.45 GHz microwave,this dimension is 72 mm,which should theoretically prevent transmission of the microwave into the discharge chamber and no plasma can be *** 2006 Peking University(PKU)has successfully developed a series of permanent magnet 2.45 GHz microwave ion sources(PKU PMeCRs)with a discharge chamber less than 50 mm,capable of delivering tens of mA beams for *** explain this anomalous phenomenon,a hybrid discharge heating(HDH)mode that combines surface wave plasma and electron cyclotron heating has been *** HDH mode not only successfully explains PKU PMeCRs,but also predicts that the optimized inner diameter of the plasma chamber is 24 mm,which is confirmed by experiments involving different liners in the miniaturized microwave ion source.

关键词： Miniaturized 2.45 GHz eCR source Hybrid discharge mode Hydrogen plasma

Study on the Protection of Polysaccharide and Flavone in Artemisia Annua L in Different Places to DNA with Fluorescence Probe

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Study on the Protection of Polysaccharide and Flavone in Art...

Role of the Greenland Sea ice anomaly in the late-spring drought over Northwest China

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作者： H.R.Zhang j.e.chen C.j.Li Lab of Biochemical Analysis Xinzhou Teachers University Shanxi 034000 China

＜正＞The protection of polysaccharide and flavone compounds in14 kinds of Chinese herbs of Artemisia annua L at different growing places such as Hunan,Chongqing,Beijing *** DNA was comparatively *** fluorescence integration intensity of DNA,eB and extracts containing polysaccharide and flavone compounds from 14 kinds of artemisia annua L were determined with eB as a sensitive fluorescence probe.D can

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 1-5页

作者： Yang Liu Huopo chen Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and evaluation of Meteorological Disasters Nanjing University for Information Science and TechnologyNanjingChina

Drought across Northwest China in late spring has exerted a vital effect on the local climate and agricultural production,and has been alleviated during the past *** study explored the influence of the preceding Arctic sea ice on the May drought in Northwest China caused by the precipitation *** analysis indicated that when the Greenland Sea ice concentration is abnormally high during February to April,the dry conditions in Northwest China tend to be *** increase of sea ice in the Greenland Sea can excite a meridional circulation,which causes sea surface temperature(SST)anomalies in the North Atlantic via the sea-air interaction,manifested as significant warm SST anomalies over the south of Greenland and the subtropical North Atlantic,but negative SST anomalies over the west of the *** abnormal SST pattern maintains to May and triggers a zonal wave train from the North Atlantic through Scandinavia and Central Asia to Northwest China,leading to abnormal cyclones in Northwest ***,Northwest China experiences a more humid climate than usual.

关键词： Arctic sea ice Greenland Sea North Atlantic SST Drought Northwest China

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Proton beams from intense laser-solid interaction:effects of the target materials

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Matter and Radiation at extremes 2020年第6期5卷 42-47页

作者： Y.X.Geng D.Wu W.Yu Z.M.Sheng S.Fritzsche Q.Liao M.j.Wu X.H.Xu D.Y.Li W.j.Ma H.Y.Lu Y.Y.Zhao X.T.He j.e.chen C.Lin X.Q.Yan Key Laboratory of HeDP of the Ministry of education CAPTand State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China Institute for Fusion Theory and Simulation Department of PhysicsZhejiang University310058 HangzhouChina State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics201800 ShanghaiChina SUPA Department of Physics University of StrathclydeGlasgow G40NGUnited Kingdom Key Laboratory for Laser Plasmas(Ministry of education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Helmholtz Institut-jena and Friedrich-Schiller-University D-07743 JenaGermany

We report systematic studies of laser-driven proton beams produced with micrometer-thick solid targets made of aluminum and plastic,*** effects of the target materials are found on the total charge,cutoff energy,and beam spot of protons in the experiments,and these are described well by two-dimensional particle-in-cell simulations incorporating intrinsic material *** is found that with a laser intensity of 8×10^(19) W/cm^(2),target normal sheath acceleration is the dominant mechanism for both types of *** a plastic target,the higher charge and cutoff energy of the protons are due to the greater energy coupling efficiencies from the intense laser beams,and the larger divergence angle of the protons is due to the deflection of hot electrons during transport in the *** also find that the energy loss of hot electrons in targets of different thickness has a significant effect on the proton cutoff *** consistent results obtained here further narrow the gap between simulations and experiments.

关键词： properties. intense solid

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engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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journal of energy Chemistry 2025年第1期100卷 215-225页

作者： jiaye Li Shuang Pan Yihuang chen Qiong Liu College of Chemistry and Materials engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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journal of energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing chen Chao Wu Xiaoling Liu Biao Meng Tao chen Yu Han jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANeS） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Single atom catalyst Synergy effect Carbon catalyst electrocatalysis

Ammonia pyrolysis oxidation excited by nanosecond pulsed discharge:Global/fluid models hybrid solution

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journal of energy Chemistry 2025年第1期100卷 385-396页

作者： Mingming Zhang Hanyu Wu Qi chen jiaxin Yang Bonan Liu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University China University of Petroleum

The kinetic characteristics of plasma-assisted oxidative pyrolysis of ammonia are studied by using the global/fluid models hybrid solution ***,the stable products of plasma-assisted oxidative pyrolysis of ammonia are *** results show that the consumption of NH3/O2and the production of N2/H2change linearly with the increase of voltage,which indicates the decoupling of nonequilibrium molecular excitation and oxidative pyrolysis of ammonia at low ***,the detailed reaction kinetics mechanism of ammonia oxidative pyrolysis stimulated by a nanosecond pulse voltage at low pressure and room temperature is *** on the reaction path analysis,the simplified mechanism is *** detailed and simplified mechanism simulation results are compared with experimental data to verify the accuracy of the simplified ***,based on the simplified mechanism,the fluid model of ammonia oxidative pyrolysis stimulated by the nanosecond pulse plasma is established to study the pre-sheath/sheath behavior and the resultant consumption and formation of key *** results show that the generation,development,and propagation of the pre-sheath have a great influence on the formation and consumption of *** consumption of NH3by the cathode pre-sheath is greater than that by the anode pre-sheath,but the opposite is true for OH and O（1S）.However,within the sheath,almost all reactions do not ***,by changing the parameters of nanosecond pulse power supply voltage,it is found that the electron number density,electron current density,and applied peak voltages are not the direct reasons for the structural changes of the sheath and ***,the discharge interval has little effect on the sheath structure and gas mixture *** research results of this paper not only help to understand the kinetic promotion of non-equilibrium excitation in the process of oxidative pyrolysis but also help to explore th

关键词： Nanosecond pulsed discharge Ammonia Oxidative pyrolysis Fluid model Global model

NeCAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno Michael K.e.Schafer Sudena Wang Michael j.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal eF-hand calcium-binding proteins 1–3(NeCAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one eF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NeCAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NeCAB2 interacts with predominantly striatal G-protein-coupled receptors, while NeCAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NeCAB proteins exhibit distinct subcellular localizations: NeCAB1 is found in the nucleus and cytosol, NeCAB2 resides in endosomes and the plasma membrane, and NeCAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NeCAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NeCAB proteins by controlling the availability of protein–protein interaction domains situated between the eF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium eF hand mitochondria nervous system signal transduction

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Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin jia Artem S.Pilipchuk Sibo Huang chen Shen Almas F.Sadreev Yong Li Andrey e.Miroshnichenko School of Physics and electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical engineering Rowan University School of engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances