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Chinese Physics Letters 1996年第11期13卷 829-832页

作者： ni guo-quan ZHOU Ru-fang ZHAI Hua-jin WANG Yu-zhu Shanghai Institute of Optics and Fine Mechanics Joint Laboratory for Quantum OpticsChinese Academy of SciencesShanghai 201800

Aluminum anion clusters are generated by laser vaporization and molecular beam *** abundance spectra exhibit a pronounced odd-even alternation for clusters ranging from n=5 to n=17,which is related to the presence of trace oxygen and water resident in He carrier gas and explained by electron pairing *** addition,confirmation of jellium model predictions is revealed at peaked A113-,and for the first time at Al_(7)O^(-).A local maximum Al7-is also observed.

关键词： confirmation pairing Molecular

High-Energy Ions Emitted from Ar Clusters Irradiated by Intense Femtosecond Laser Pulses

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Chinese Physics Letters 2000年第2期17卷 99-100页

作者： LI Zhong LEI An-Le ni guo-quan XU Zhi-Zhan Laboratory for Hligh intensity Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Laboratory for quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

We have experimentally studied the energy spectra of Ar ions emitted from Ar clusters irradiated by intense femtosecond laser pulses. The Ar clusters were produced in the adiabatic expansion of Ar gas into vacuum at high backing pressures. The laser peak intensity was about 2×106 W/cm2 with a pulse duration of 45 fs. The maximum and the average energies of Ar ions are 0.2 MeV and 15kev at a backing pressure of 2. S MPa, respectively. They are almost independent of the backing pressures in the range of 0.6 to 4.5 MPa.

关键词： Femto laser Pulse

Photoionization Time-of-Flight Mass Spectra of Aluminum Clusters-Associated Complexes

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Chinese Physics Letters 1997年第9期14卷 663-666页

作者： ni guo-quan ZHOU Ru-fang ZHAI Hua-jin WANG Yu-zhu Laboratory for quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

Using a laser vaporization/pulsed molecular beam source,photoionization time-of-flight mass spectra of bare aluminum clusters Aln(n up to larger than 70)and of carbon-,oxygen-,and hydrogen-adducted aluminum clusters-associated complexes are *** cause of the observed odd-even alternation in reactivity of Aln and the formation mechanism of the informative products are discussed.

关键词： reactivity mechanism clusters

Photoionization Mass Spectrometric Study of Neutral Bare Aluminum Clusters and Aluminum-Carbon Mixed Clusters

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Chinese Physics Letters 1997年第12期14卷 901-904页

作者： ni guo-quan ZHOU Ru-fang ZHAI Hua-jin WANG Yu-zhu Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciencesand Joint Laboratory for Quantum OpticsChinese Academy of SciencesShanghai 201800

Photoionization time of flight mass spectra of bare aluminum and aluminum-carbon mixed clusters as well as a variety of oxygen-and oxygen-carbon-adducted aluminum clusters are recorded and *** discontinuities in the mass abundance spectra at AI_(7),AI_(13),AI_(23),AI_(7)C,AI_(13)C,and AI_(24)C are *** findings are interpreted in terms of the electronic and geometric structures of these species.

关键词： species finding assigned

Enhanced Ionization of Linear Polyatomic Molecular Ions in Ultrashort Laser Fields

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Chinese Physics Letters 1999年第4期16卷 264-266页

作者： LEI An-le ni guo-quan LI Zhong ZHAI Hua-jin XU Zhi-zhan Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800 Institute of Nuclear Physics and Chemistry P.O.Box 525-74Chengdu 610003

The ionization behavior of linear polyatomic molecular ions in ultrashort,intense laser fields was investigated with the time-dependent Schrodinger equation solved by the standard split-operator *** enhanced ionization effect was found as a general feature in the ions when the internuclear separation was in a critical distance range and can be explained in terms of the field-induced over-barrier ionization *** addition,the ionization energy does not influence the ionization probability significantly.

关键词： mechanism. ionization atomic

Two Types of Mass Abundance Distributions for Anionic Carbon Clusters Investigated by Laser Vaporization and Pulsed Molecular Beam Techniques

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Chinese Physics Letters 2000年第3期17卷 197-199页

作者： ZHAI Hua-Jin LIU Bing-Chen ZHOU Ru-Fang ni guo-quan XU Zhi-Zhan Laboratory for quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Laboratory for High Intensity Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

Two types of mass spectra for anionic carbon clusters Cn have been revealed using laser vaporization and pulsed molecular beam *** less structured mass spectrum characteristic of the magic-numbers at n=5,8,",15,and 17 is established at the early stage of the cluster formation process,namely,in the laser vaporization,*** more structured one is featured for a regular odd-even alternation and the magic numbers at n=IO,12,16,18j 22j and 28,and has been developed only after extensive clustering and qnenching processes,where low-energy electron attachment plays a vital *** between these two types of mass spectra can be realized by controlling either the strength of the pulsed gas flow or the synchronism between the gas How and the laser vaporization.

关键词： pulsed Transition Molecular

Observation of Electronic Shells and Characteristic Products from Mass Abundance Spectra of Al Cluster and Al-C Cluster Anions

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Chinese Physics Letters 2000年第9期17卷 658-660页

作者： LIU Bing-chen ZHAI Hua-Jin ZHOU Ru-fang ni guo-quan XU Zhi-Zhan Laboratory for quantum Optics Chinese Academy of SciencesShanghai 201800 Laboratory for High Intensity Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800

Using a laser vaporization/pulsed molecular beam cluster source,Al cluster anions and Al-C mixed cluster anions are produced and recorded by a time of flight mass *** abundance spectra of the Al cluster anions in the size range from Al_(2)^(-)to Al_(42)^(-)show that Al_(13)^(-),Al_(23)^(-),Al_(35)^(-),and slightly,Al_(37)^(-)are local maxima,as predicted by the electronic jellium *** clusters Aln C-and Aln C_(2)^(-)are also shown,among which the most abundant species are Al3 C2,Al6 C_(2)^(-),A_(l7)C^(-)and A_(l7)C_(2)^(-)in the small size *** formation mechanism of these products is discussed.

关键词： cluster slightly anions

More Magic Numbers in Titanium-Carbon Anion Clusters: Can This Be Explained by Any Structural Growth Pattern?

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Chinese Physics Letters 2001年第12期18卷 1582-1585页

作者： ZHAI Hua-Jin LIU Bing-Chen ZHOU Zheng-Wen ZHOU Ru-Fang ni guo-quan XU Zhi-Zhan Laboratory for quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesP.O.Box 800-211Shanghai 201800 Laboratory for High Intensity Optics Shanghai Institute of Optics a nd Fine MechanicsChinese Academy of SciencesP.O.Box 800-211Shanghai 201800

Titanitum-carbon anion clusters with a mass range up to 1800 amu have been generated in a Smalley-type cluster source involving a target rod composed of titanium and graphite powders, and have been analysed by time-of-flight mass spectrometry. In the lower mass range (up to 1200 amu), our mass spectrum reproduces all the magic numbers, which have been reported previously, i.e. Ti_(3)C_(8)^(-), Ti_(6)C_(13)^(-), Ti_(7)C_(13)^(-), Ti_(9)C_(15)^(-), Ti_(13)C_(22)^(-), and Ti_(14)C_(24)^(-), in spite of many differences in experimental conditions. In the higher mass range (1200-1800 amu), we observe new magic numbers at Ti_(15)C_(26)^(-), Ti_(20)C_(33)^(-)/Ti_(20)C_(34)^(-) and Ti_(25)C_(42)^(-), which cannot be accounted for by the previously proposed structural growth patterns. All the magic and local maximum Ti_(x)C_(y) peaks have a metal-to-carbon ratio of approximately 1:1.7. The present results suggest a further complexity to the structural growth patterns of the transition metal-carbon mixed cluster systems.

关键词： cluster Titanium structural

Role of Cluster Geometry in Evolution of Electronic Structures of Small Aluminum Clusters

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Chinese Physics Letters 1997年第12期14卷 897-900页

作者： ZHAI Hua-jin ZHAO Ji-jun ni guo-quan ZHOU Ru-fang WANG Guang-hou WANG Yu-zhu Laboratory for quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Department of Physics and National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

The electronic structures of small aluminum clusters,Al_(n)(n=5-24),are investigated by a localized-orbital theory based on the tight-binding ***-numbered clusters each exhibit a HOMO-LUMO gap maximum,and simultaneously an s-p gap minimum,but not necessarily an ionization potential maximum,where HOMO-LUMO gap denotes the energy gap between the highest occupied orbital and the lowest unoccupied orbital of the *** revealed is an irregular odd-even alternation in HOMO-LUMO gaps for Al_(n)(n=7-24).Cluster geometry either contributes to or dominates these findings.

关键词： cluster orbital occupied

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing Yin Hongyin Ma Yang Qu Jiaxin Ren Yingying Sun Zhen-ni guo Yi Yang Stroke Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research Center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents