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Study of baryon number transport dynamics and strangeness conservation effects using Ω-hadron correlations

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Nuclear Science and Techniques 2024年第7期35卷 147-156页

作者： Wei-Jie dong Xiao-Zhou Yu Si-Yuan Ping Xia-Tong Wu Gang Wang Huan-zhong Huang Zi-Wei Lin Key Laboratory of Nuclear physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China department of physics and Astronomy University of CaliforniaLos AngelesCA 90095USA department of physics East Carolina UniversityGreenvilleNC 27858USA

In nuclear collisions at RHIC energies, an excess of Ω hyperons over ■ is observed, indicating that Ω has a net baryon number despite s and s quarks being produced in pairs. The baryon number in Ω may have been transported from the incident nuclei and/or produced in the baryon-pair production of Ω with other types of anti-hyperons such as Ξ. To investigate these two scenarios, we propose to measure the correlations between Ω and K and between Ω and anti-hyperons. We use two versions, the default and string-melting, of a multiphase transport(AMPT) model to illustrate the method for measuring the correlation and to demonstrate the general shape of the correlation. We present the Ω-hadron correlations from simulated Au+Au collisions at ■ =7.7 and 14.6 Ge V and discuss the dependence on the collision energy and on the hadronization scheme in these two AMPT versions. These correlations can be used to explore the mechanism of baryon number transport and the effects of baryon number and strangeness conservation on nuclear collisions.

关键词： Baryon number transport Strangeness conversation Correlation Gluon junction

PIXE and INAA studies on ancient potteries from Guangfulin relics in shanghai

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Progress in Natural Science:Materials International 2007年第11期17卷 1348-1356页

作者： Lin Jiawei1, Cheng Huansheng1, Zhang Zhengquan1, Zhang Bin1, Feng Songlin2, Song Jian3, Gao Menghe4.and Zhu Dan1(1. Applied Ion Beam physics Laboratory, Key Laboratory of the Ministry of Education, Institute of Modern physics, fudan university, shanghai 2.043., China 2. Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy physics, Beijing 100039, China 3. shanghai Museum, shanghai 200003, China 4. department of Cultural Heritage and Museology, fudan university, shanghai 2.043., China) Applied Ion Beam physics Laboratory Key Laboratory of the Ministry of Education Institute of Modern Physics Fudan University Shanghai 200433 China Key Laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Beijing 100039 China shanghai Museum Shanghai 200003 China department of Cultural Heritage and Museology Fudan University Shanghai 200433 China

This paper reports the study of ancient potteries unearthed from the Guangfulin site in shanghai. From the external features of these potteries, archeologists can classify them into two different cultural types: Liangzhu culture (local culture) and a new culture which might be derived elsewhere, but they can not recognize whether they were produced in the same place. Proton induced X-ray emission (PIXE) and instrumental neutron activation analysis (INAA) were used to measure the chemical compositions of the samples and the results were analyzed using multivariate statistics. We found that the two methods can complement each other and their database can be mutually referenced in the study of ancient potteries. Experimental results show that the compositions of the potteries from the two cultural types are different, which means that the materials for ancient potteries of new culture originate from elsewhere. This supports the archaeologists’ speculation that a group of ancient people migrated to shanghai from some other places 4.00 years ago.

关键词： PIXE INAA factor analysis Guangfulin ancient pottery

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science China(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2, SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4.1. Faculty of Physical Engineering, Zhengzhou university, Zhengzhou 4.0052, China 2. department of physics, Beijing Normal university, Beijing 100875, China 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 4.0000, China 4. Institute of Modern physics, fudan university, shanghai 2.043., China Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China department of physics Beijing Normal University Beijing 100875 China Institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China Institute of Modern physics Fudan University Shanghai 200433 China

34.samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

Phase Conjugation by Degenerate Four-wave Mixing in Nematic Liquid Crystals

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Chinese Journal of Lasers 1997年第5期B6卷 403-408页

作者： zhong Xiaoxia WU Jiada CHEN shuchao WU Changzheng LI Fuming (State Key Joint Lab for Materials Modification by Laser, Ion and Electron Beams department of physics, {4., shanghai 2.043., Chinadepartment of physics Xiamen university, Xiamen 3 fudan Univ Shanghai China

Phase conjugation by degenerate four-wave mixing(DFWM) due to the optically induced molecular reorientation in nematic liquid crystals(NLC) is studied, and an analytical expression for the efficiency of phase conjugation is presented. Calculations of the efficiency are given for 5CB liquid crystal for further investigstion of the dependences of the phase conjugation on the angle between the pump beam and the probe beam as well as on the angle between the plane of the incident beams and the nematic director n. The physical mechanism is also discussed.

关键词： nematic liquid crystal four-wave mixing phase conjugation

Surface Nitridation of Molybdenum by Laser-promoted Reaction

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Chinese Journal of Lasers 1997年第2期B6卷 161-168页

作者： WU Jiada WU Changzheng zhong Xiaoxia SONG Zhoumo LI Fuming(department of physics, Fundan university, {4.)(Deprtment of Applied physics, Northwestern Polytechnical university, Xi'an 710072, China) fudan Univ Shanghai China

Experimental results are reported about the surface nitridation of molyly denum by repeated pulsed laser irradiation on molyboenum foils in pure nitrogen atmosphere. In this laser treatment, the laser irradiation activates nitrogen and melts Mo surface, initating a nitridation reaction in liquid phase. The obtained nitride layers were analyzed and characterized by scanning electron micrography, Auger electron spectroscopy and X -ray diffraction. It is found that the nitride layers contain γ-Mo2N phase and have microstructure much denser than that of the original material. Surface heating and melting and transicnt shock waves induced by laser pulses could account for the microstructure densification of the nitride layers.

关键词： laser-promoted reaction laser heating and melting surface nitridation

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UPS和功函数研究氧在电解银上的吸附

化学学报 1989年第8期47卷 779-782页

作者：包信和邓景发董树忠复旦大学化学系复旦大学现代物理研究所

经电角法制得的多晶银有很多独特的物理和化学性质，作为催化剂，用于甲醇氧化制甲醛的工业过程，不需要任何附载，得到了非常高的转化率和选择性；对这种高纯度的金属催化剂的理论研究可望能直接解释工业过程中的一些问题。由于表面结... 详细信息

经电角法制得的多晶银有很多独特的物理和化学性质，作为催化剂，用于甲醇氧化制甲醛的工业过程，不需要任何附载，得到了非常高的转化率和选择性；对这种高纯度的金属催化剂的理论研究可望能直接解释工业过程中的一些问题。由于表面结构的特殊性，与单晶银相比，氧在这种电解银上的吸附和脱附有很大的差别，在超高真空条件下，对氧在单晶银[如Ag(110）]吸附的研究结果表明，在清洁的Ag(110)表面，只有当氧的吸附湿度低于185K时，才能观察到表面未解离的分子氧吸附物种，随着吸附湿度的升高，分子氧解离为原子态，原子态吸附氧在表面的结构为（n×1），随着覆盖度的增加,n从7到2，饱和吸附时为0.5单层。XPS、TDS以及^18O2与^16O2同位素交换结果表明：电解银表面除了存在大量的解离的原子态吸附氧外，在室温下就能检测到表面存在的未解离的分子态吸附氧种。本文报道了用紫外光电子能谱（UPS),热脱附(TDS)和表面功函数连续测量等手段对氧与电解银表面相互作用过程中的电荷传递、成键以及吸附动力学等研究的实验结果。

关键词：电解银氧吸附紫外光电子能谱表面功能函数热脱附

A Study on Uptake and Localization of Merocyanine 54. (MC54.) in Murine Myeloid Leukemia Cells by Confocal Laser Scanning Microscopy (CLSM)

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Chinese Journal of Lasers 2000年第3期9卷 35-41页

作者： J. Y. Chen-1 N. H. Cheung-2 S. C. Chen-2, M. C. Fung-3 W. N. Leung-4.N. K. Mak- 4. ( -1department of physics, fudan university, shanghai 2.043., China -2department of physics, Hong Kong Baptist university, Hong Kong, China -3department of Bi 复旦大学上海香港浸会大学香港香港大学香港

The intracellular localization of merocyanine 54. (MC54.), a photosensitizer commonly used in the photo-inactivation of leukemia cells, was studied using confocal laser scanning microscopy. It was found for the first time that MC54. not only localized in the plasma membrane but also in the cytoplasm and the nuclear membrane of the murine myeloid leukemia M1 and WEHI 3B (JCS) cells. Exposure of MC54. treated leukemia cells to light under conditions that could cause photobleaching did not cause the redistribution of cell-bound MC54.. Rapid localization of MC54. in the cytoplasm was observed 5 minutes after exposure of leukemia cell to MC54., indicating that MC54. could promptly be internalized by these two leukemia cell lines. In contrast, localization of MC54. was limited only to the plasma membrane of erythrocytes. These results suggest that the binding pattern of MC54. is cell type dependent and may be related to the efficacy of photosenitization in photodynamic therapy.

关键词： merocyanine 54. Confocal Laser Scanning Microscopy Myeloid Leukemia cell

Jackknife and Bootstrap Tests of the Composition Vector Trees

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Genomics, Proteomics & Bioinformatics 2010年第4期8卷 262-267页

作者： Guanghong Zuo1,2, Zhao Xu1,3, Hongjie Yu1,4. and Bailin Hao1,5,6 1T-Life Research Center & department of physics, fudan university, shanghai 2.043., China 2{4. Institute of Applied physics, Chinese Acadamy of Sciences, {4. 201800, China 3Applied Biosystems, Inc., Beijing 100027, China 4.7}-VARI Center for Genetic Epidemiology, fudan university, shanghai 2.043., China 5Institute of Theoretical physics, Chinese Acadamy of Sciences, Beijing 100190, China 6Santa Fe Institute, Santa Fe, NM 87505, USA. [a] T-Life Research Center & department of physics fudan university shanghai 2.043. China [b] shanghai Institute of Applied physics Chinese Acadamy of Sciences shanghai 201800 China [c] Applied Biosystems Inc. Beijing 100027 China [d] fudan-VARI Center for Genetic Epidemiology fudan university shanghai 2.043. China [e] Institute of Theoretical physics Chinese Acadamy of Sciences Beijing 100190 China [f] Santa Fe Institute Santa Fe NM 87505 USA

Composition vector trees （CVTrees） are inferred from whole-genome data by an alignment-free and parameter-free method. The agreement of these trees with the corresponding taxonomy provides an objective justification of the inferred phylogeny. In this work, we show the stability and self-consistency of CVTrees by performing bootstrap and jackknife re-sampling tests adapted to this alignment-free approach. Our ultimate goal is to advocate the viewpoint that time-consuming statistical re-sampling tests can be avoided at all in using this alignment-free approach. Agreement with taxonomy should be taken as a major criterion to estimate prokaryotic phylogenetic trees.

关键词： composition vector phylogeny topological distance bootstrap jackknife CVTree

Identifying Three New AGNs among Fermi Unidentified Gigaelectronvolt Sources

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Research in Astronomy and Astrophysics 2024年第7期24卷 257-267页

作者： shun-Hao Ji zhong-Xiang Wang Qiang-Meng Huang Ruo-Heng Yang department of Astronomy School of Physics and AstronomyYunnan UniversityKunming 650091China shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China

We report our identification of three gigaelectronvoltγ-ray sources,4.GL J0502.6+0036,4.GL J1055.9+6507,and 4.GL J1708.2+5519,as Active Galactic Nuclei(AGNs).They are listed in the latest Fermi-Large Area Telescope source catalog as unidentified *** find that the sources all showedγ-ray flux variations in recent *** different survey catalogs,we are able to find a radio source within the error circle of each source's *** analysis of optical sources in the fields allows us to determine the optical counterparts,which showed similar variation patterns to those seen inγ-*** optical counterparts have reported redshifts of 0.6,1.5,and 2.3,respectively,estimated from photometric *** addition,we also obtain an X-ray spectrum of 4.GL J0502.6+0036 and a flux upper limit on the X-ray emission of 4.GL J1055.9+6507 by analyzing the archival *** broadband spectral energy distributions of the three sources from radio toγ-rays are *** mainly theγ-ray properties of the three sources with those of different sub-classes of AGNs,we tentatively identify them as *** optical spectroscopy is highly warranted for obtaining their spectral features and thus verifying the identification.

关键词： gamma-rays galaxies-(galaxies)BL Lacertae objects general-(galaxies)quasars general