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Synthesis and Cation-Mediated Electron Transfer in Fluorescence Quenching of Donor-Acceptor Podands

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Chinese Chemical Letters 2000年第9期11卷 767-770页

作者： Hua JIANG hui jun xu Institute of Photographic Chemistry, Chinese Academy of Sciences, Beijing, 100101 Chinese Acad Sci Inst Photog Chem Beijing 100101 Peoples R China

Reduced rate constants of photoinduced electron transfer in intramolecular fluorescence quenching of donor-acceptor podands induced by cation-complexation are observed in the highly exothermic reactions.

关键词： electron transfer donor acceptor podands

Nonlinear quantum interferometry with Bose condensed atoms

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Frontiers of physics 2012年第1期7卷 109-130页

作者： Chaohong Lee (1) Jiahao Huang (1) Haiming Deng (1) hui Dai (1) jun xu (1) 1. State Key Laboratory of Optoelectronic Materials and Technologies School of Physics and Engineering Sun Yat-Sen University Guangzhou 510275 China

In quantum interferometry, it is vital to control and utilize nonlinear interactions for the achievement of high-precision measurements. Due to their long coherence time and high controllability, ultracold atoms including Bose condensed atoms have been widely used for quantum interferometry. Here, we review recent progress in theoretical studies of quantum interferometry with Bose condensed atoms. In particular, we focus on nonlinear phenomena induced by atom-atom interactions, and how to control and utilize these nonlinear phenomena. With a mean-field description, due to atom-atom interactions, matter-wave solitons appear in the interference patterns, and macroscopic quantum self-trapping exists in Bose-Josephson junctions. With a many-body description, atom-atom in- teractions can generate non-classical entanglement, which can be utilized to achieve high-precision measurements beyond the standard quantum limit.

关键词： nonlinear quantum interferometry Bose Einstein condensate Bose-Josephson junction

The Mixed LB film of Crowned Phthalocyanine and Picrate

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Chinese Chemical Letters 1998年第6期9卷 573-575页

作者： Xi You LI hui jun xu(Institute of Photographic Chendstry, Chinese Academy of Sciences, Beijing 100101) Chinese Acad Sci Inst Photog Chem Beijing 100101 Peoples R China

The mixed LB film of mono crown ether substituted phthalocyanine (CPc) and potassium picrate (PiK) were prepared by adding potassium picrate in subphase. The pi-A isotherms show that the addition of PiK in subphase increases the orientation angles of phthalocyanine in monolayers. The absorption spectra revealed that the monolayer can be transferred to substrates easily. X-ray diffraction results show that the mixed film possesses the same thickness as that of pure phthalocyanine film.

关键词： mono crown ether phthalocyanine LB film picrate

SYNTHESIS AND CRYSTAL STRUCTURE OF 4,5-DIBROMO-o-OXYLYL-17-CROWN-5

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Chinese Chemical Letters 1996年第8期7卷 699-700页

作者： Guo chang XIONG Qing Fu ZHOU hui jun xu(Institute of Photographic Chemistry, Chemistry, Academia Sinica, Beijing 100101) ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

The title compound [C16H22Br2O5] (3), was synthesized and characterized by H-1-NMR, MS and elemental analysis. Pale yellow prism crystallized from anhydrous ethanol solution was investigated by X-ray structural analysis. Crystal data: orthorhombic system space group Pbca, Mr=454.2, a=17.664(4)Angstrom b=8.625(2)Angstrom, c=24.269(5)Angstrom, z=8, Dc=1.632g/cm(3), F(000)=1776. The structure was solved by direct methods and refined to final R=0.0362, Rw=0.0357 for 1029 observed reflections with F>6.0 sigma(F).

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Laser-Constructing 3D Copper Current Collector with Crystalline Orientation Selectivity for Stable Lithium Metal Batteries

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Energy & Environmental Materials 2024年第6期7卷 129-139页

作者： hui Li Gang Wang Jin Hu jun Li Jiaxu Huang Shaolin xu Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518000China

The practical application of lithium(Li)metal anodes in high-capacity batteries is impeded by the formation of hazardous Li *** address this challenge,this research presents a novel methodology that combines laser ablation and heat treatment to precisely induce controlled grain growth within laser-structured grooves on copper(Cu)current ***,this approach enhances the prevalence of Cu(100)facets within the grooves,effectively lowering the overpotential for Li nucleation and promoting preferential Li *** approaches that modify the entire surface of collectors,our work focuses on selectively enhancing lithiophilicity within the grooves to mitigate the formation of Li dendrites and exhibit exceptional performance *** half-cell with these collectors maintains a remarkable Coulombic efficiency of 97.42%over 350 cycles at 1 mA cm^(−2).The symmetric cell can cycle stably for 1600 h at 0.5 mA cm^(−2).Furthermore,when integrated with LiFePO4 cathodes,the full-cell configuration demonstrates outstanding capacity retention of 92.39%after 400 cycles at a 1C discharge *** study introduces a novel technique for fabricating selective lithiophilic three-dimensional(3D)Cu current collectors,thereby enhancing the performance of Li metal *** insights gained from this approach hold promise for enhancing the performance of all laser-processed 3D Cu current collectors by enabling precise lithiophilic modifications within complex structures.

关键词： copper current collector heat treatment laser processing lithium metal battery selective crystalline orientation

The Synthesis and Film Forming Properties of Unsymmetrical Phthalocyanine Bearing One Crown Ether Void

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Chinese Chemical Letters 1997年第9期8卷 815-818页

作者： Xi You LI Guo Xiang XIONG hui jun xu(The Institute of Photographic Chemistry, Chinese Academy of Sciences. Beijing 100101) Institute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China

The synthesis of phthalocyanines bearing one crown ether macrocycle and three alkoxyl chains is described. They form stable monolayers and can be employed for the preparation of multilayer films by the Langmuir-Blogett technique. The orientations of the molecules in the film were affected by alkali metal ions in the subphase. lt is suggested that a kind of 'sandwich' dimer was formed in the film induced by potassium ions

关键词： HNMR MS Figure The Synthesis and Film Forming Properties of Unsymmetrical Phthalocyanine Bearing One Crown Ether Void

Photoinduced　Intramolecular　Electron　Transfer　in　an　Oblique　Zinc　Phthalocyanine－Viologen　Linked　System

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Chinese Chemical Letters 1996年第10期7卷 931-934页

作者： Hong Jian TIAN Qing Fu ZHOU hui jun xu(Institute of Photographic Chemistry. Academia Sinica. Beijing 100101) ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

The spectroscopic properties and photoinduced electron transfer process have been studied in zinc phthalocyanine-viologen system with bisphenol A (ZnPcAV2+). It was found that the excited singlet state of zinc phthalocyanine moiety is quenched and the fluorescence lifetime is reduced by the linked viologen. Nanosecond laser photolysis studies showed that intramolecular quenching of the excited triplet state of zinc phthalocyanine moiety by the attached viologen occurred giving reduced viologen radical ion (V+) that survived over 50 μs.

关键词： Electron Intramolecular

Precipitation evolution and properties of Cu-15Ni-8Sn alloys via Al microalloying during ageing

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Rare Metals 2024年第10期43卷 5216-5228页

作者： Wei Luo Li-jun Peng xu-jun Mi Hao-Feng Xie Yi-Cheng Cao Shu-hui Huang State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd. GRIMAT Engineering Institute Co. Ltd. General Research Institute for Nonferrous Metals School of Materials Science and Engineering South China University of Technology

Studies have shown that microalloying Cu-Ni-Sn alloys using Al inhibits discontinuous precipitation reactions;however,the mechanism has not been investigated ***,this study explored the properties and precipitation evolution of Cu-15Ni-8Sn alloys without and with 1 wt%Al（Cu-15Ni-8Sn-1Al） during ageing at 500℃ through X-ray diffraction （XRD）,scanning electron microscopy and high-angle annular dark-field scanning transmission electron *** results revealed that in Cu-15Ni-8Sn alloy,DO22ordering first occurred after spinodal decomposition,subsequently transitioning to an L12ordering phase,during which the discontinuous precipitates gradually nucleated at the grain boundaries and formed *** alloy hardness increased sharply with ordering and then decreased rapidly after reaching its peak value,due to the dominance of the discontinuous precipitation ***,the DO22ordered phase did not appear during the ageing of Cu-15Ni-8Sn-1Al alloy,and a Ni3(Alx,Sn1-x) intermetallic compound with L12structure was formed,consuming Ni and Sn atoms,thereby significantly suppressing the discontinuous precipitation reaction and improving the stability during prolonged *** tensile strength （yield strength） of Cu-15Ni-8Sn and Cu-15Ni-8Sn-1Al alloys at peak hardness were 855 （755） and 936 MPa （892 MPa）,respectively,and their main strengthening mechanisms were solid solution strengthening and precipitation *** addition of 1 wt% Al effectively improved the precipitation strengthening effect of Cu-Ni-Sn alloys but severely decreased the ductility.

关键词： Al addition Cu-15Ni-8Sn Precipitation sequence Strengthening mechanism

Non-cardiogenic acute pulmonary edema in elderly patient with Dressier syndrome associated pulmonary embolism

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Journal of Geriatric Cardiology 2016年第12期13卷 998-1001页

作者： hui-Chun YU Xiao-Bing MA Zhen-Qing WANG hui-jun xu Ping WANG Feng-Ping AN Yu-Chuan HU Guang-Bin CUI xu-Fang BAI He LI Department of Gerontology Xiqing Hospital Tianjin China Cardiovascular Division of Gerontology Pingjin Hospital Logistic University of CAPF Tianjin China Postgraduate School of Tianjin University of Traditional Chinese Medicine Tianjin China Department of Radiology Tangdu Hospital the Fourth Military Medical University Xi'an Shaanxi China University of Ottawa Heart Institute Ottawa ON Canada

Pulmonary embolism （PE） is a common cardiovascular and cardiopulmonary illness and the incidence increases exponentially with age. Because the clinical signs and symptoms are non-specific, its diagnosis is always di... 详细信息

关键词： Dressier syndrome Non-cardiogenic acute pulmonary edema Pulmonary Embolism The elderly