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Enhancement of the Femtosecond Third Harmonic Generation by Charge Transfer Process in Poly (N-Vinylcarbazole) /C_(60) Film

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Chinese Physics Letters 1997年第5期14卷 356-359页

作者： qian Jiang ZHAO Li WANG Gong-ming qian shi-xiong LIU Xian-nian ZHENG Qi-ke Department of Physics Fudan UniversityShanghai 200433 Laser Chemistry Institute Fudan UniversityShanghai 200433

The femtosecond third harmonic generaction(THG)output has been measured from a series of poly(N-vinylcarbazole)(PVK),C_(60),mixed and multilayer PVK/C_(60) films which were all fabricated by physical jet deposition *** is an enhancement of femtosecond THG output from the mixed PVK/C_(60) film in comparison with other *** transfer complex in the mixed PVK/C_(60) film was considered to be the main reason for this increase of the third-order susceptibility.

关键词： technique. Femto femtosecond

Fragmentation Mechanism of Fullerenes in the Positive and Negative Ion Channels

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Chinese Physics Letters 2001年第8期18卷 1056-1059页

作者： KONG Qing-Yu ZHAO Li ZHUANG Jun qian shi-xiong LI Yu-Fen State Key Joint Laboratory for Materials Modification by Laser Ion and Electron Beamsand Department of PhysicsFudan UniversityShanghai 200433

The authors have performed the photofragmentation studies of pristine C_(60) and C_(60)/C_(70) composites on the reflectron time-of-flight mass spectrometer(RTOF MS)in the positive and negative ion *** mechanism of the formation of daughter fullerenes in the negative ion channel and the enhancement of fullerene coalescence reactions have been discussed compared to our previous studies on the linear *** 5 cm free expansion path in the RTOF experiments provides sufficient time and favorable environment for the electrons to attach to the neutral daughter species,so it is thought to play a key role for the appearance of strong mass peaks of anionic fragmentation and aggregation fullerene *** appearance of odd-numbered“fullerene”fragments is briefly discussed.

关键词： fragmentation (MS) neutral

Anomalous Photofragmentation of Fullerene Doped in Silica Aerogel-Enhanced Formation of Odd-Numbered "Fullerene" Fragments

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Chinese Physics Letters 2001年第12期18卷 1578-1581页

作者： KONG Qing-Yu ZHAO Li ZHUANG Jun qian shi-xiong LI Yu-Fen WANG Jue Department of Physics Fudan UniversityShanghai 2004332 State Key Joint Laboratory for Materials ModiGcation by Laser Ion and Electron BeamsFudan UniversityShanghai 2004333 Pohl Institute of Solid State Physics Tongji UniversityShanghai 200092

Photofragmentation of fullerene-doped silica aerogels has been investigated by the excimer laser ablation reflectron time-of-flight mass spectrometric technique. Great enhancement in the formation of odd-numbered ‘fullerene’ fragments has been observed in the negative-ion channel for the chemically doped aerogel sample. Generally, oddnumbered species C57, C55, C53 and C51 appeared in the mass spectra. Under optimM experimental conditions C55 can be even more intense than the neighbouring even-numbered carbon clusters. In contrast, for the physicallydoped sample, just like pristine C6o, only weak odd-numbered fragments were observed. In the positive-ion channel, the behaviour of all these samples is similar, no odd-numbered species was ever detected. A mechanism related to the interaction between the fullerene dopant and the silica aerogel host is suggested for the anomalous enhancement of the odd-numbered duster formation. A preliminary discussion on the structures of the oddnumbered‘fullerene’ fragments is given.

关键词： technique fragmentation silica

Photoinduced Charge Transfer in MBB-PPV/C_(60) Composite Film

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Chinese Physics Letters 2000年第11期17卷 829-831页

作者： GUO Li-Jun MA Guo-Hong SHAN Fu-Kai MO Yu-Jun qian shi-xiong Department of Physics Fudan UniversityShanghai 200433 Department of Physics Henan UniversityKaifeng 475001

The photoconductive properties of MBB-PPV/C_(60) composite films fabricated by the physical jet deposition(PJD)technique have been studied on the basis of the photoinduced charge transfer *** the photoex-citation,the transverse photoconductivity of the composite films is greatly enhanced by 4 orders of magnitude due to the efficient excitation transfer process from MBB-PPV(as donor)to C_(60)(as acceptor)occurring at the interface,the separation of charges and the existence of in-layer free *** results indicate that the conjugated polymer/fullerene composite films optimized by an appropriate configuration have potential applications in photoelectric devices and photonic fields.

关键词： composite V/C films

Singlet Exciton Migration in a Conjugated Polymer by Picosecond Time-Resolved Photoluminescence

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Chinese Physics Letters 2001年第7期18卷 944-946页

作者： MA Guo-Hong qian shi-xiong LEI Hong WANG He-Zhou WANG Rong-Qiu LI Yong-Fang Department of Physics Fudan UniversityShanghai 200433 Key Laboratory of Applied Surface Physics Fudan UniversityShanghai 200433 Institute of Ultrafast Laser Spectroscopy Zhongshan UniversityGuangzhou 510275 Institute of Chemistry Chinese Academy of SciencesBeijing 100080

The transient photoluminescence(PL)of DO-PPV(poly-(2,5-dioctyloxy-1,4-phenylene vinylene))solution in chloroform was investigated by picosecond time-resolved PL *** ultrafast rise of PL and the following single exponential decay with a time constant about 400ps were assigned to the formation of intrachain exciton and its decay process,*** redshift of the PL emission spectrum with time was caused by the subsequent exciton migration among the different conjugated segments in the DO-PPV polymer.

关键词： spectroscopy. decay exponential

Hyperglycemia activates FGFR1 via TLR4/c-Src pathway to induce inflammatory cardiomyopathy in diabetes

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1693-1710页

作者： xiong Chen Jinfu qian shiqi Liang Jianchang qian Wu Luo Yujuan shi Hong Zhu Xiang Hu Gaojun Wu Xiaokun Li Guang Liang Department of Endocrinology the First Affiliated HospitalWenzhou Medical UniversityWenzhou 325035China Chemical Biology Research Center School of Pharmaceutical SciencesWenzhou Medical UniversityWenzhou 325035China Department of Wound Repair the First Affiliated HospitalWenzhou Medical UniversityWenzhou 325035China Department of Cardiology the First Affiliated HospitalWenzhou Medical UniversityWenzhou 325035China School of Pharmaceutical Sciences Hangzhou Medical CollegeHangzhou 311399China

Protein tyrosine kinases (RTKs) modulate a wide range of pathophysiological events in several non-malignant disorders, including diabetic complications. To find new targets driving the development of diabetic cardiomyopathy (DCM), we profiled an RTKs phosphorylation array in diabetic mouse hearts and identified increased phosphorylated fibroblast growth factor receptor 1 (p-FGFR1) levels in cardiomyocytes, indicating that FGFR1 may contribute to the pathogenesis of DCM. Using primary cardiomyocytes and H9C2 cell lines, we discovered that high-concentration glucose (HG) transactivates FGFR1 kinase domain through toll-like receptor 4 (TLR4) and c-Src, independent of FGF ligands. Knocking down the levels of either TLR4 or c-Src prevents HG-activated FGFR1 in cardiomyocytes. RNA-sequencing analysis indicates that the elevated FGFR1 activity induces pro-inflammatory responses via MAPKs–NFκB signaling pathway in HG-challenged cardiomyocytes, which further results in fibrosis and hypertrophy. We then generated cardiomyocyte-specific FGFR1 knockout mice and showed that a lack of FGFR1 in cardiomyocytes prevents diabetes-induced cardiac inflammation and preserves cardiac function in mice. Pharmacological inhibition of FGFR1 by a selective inhibitor, AZD4547, also prevents cardiac inflammation, fibrosis, and dysfunction in both type 1 and type 2 diabetic mice. These studies have identified FGFR1 as a new player in driving DCM and support further testing of FGFR1 inhibitors for possible cardioprotective benefits.

关键词： Diabetic cardiomyopathy Protein tyrosine kinases FGFR1 Cardiomyocytes Inflammatory responses Toll-like receptor4 c-Src NFkB

Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

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Journal of Iron and Steel Research International 2024年第2期31卷 519-530页

作者： Ding-qian Dong Feng-yuan He Xin-hui Chen Hui Li Kai-hua shi Hui-wen xiong Xin Xiang Li Zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide *** effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in *** results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy *** tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten *** 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,*** main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior

The tangential k-Cauchy-Fueter type operator and Penrose type integral formula on the generalized complex Heisenberg group

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 181-190页

作者： REN Guang-zhen shi Yun KANG qian-qian Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023China Department of Mathematics Zhejiang University of Science and TechnologyHangzhou 310023China

The tangential k-Cauchy-Fueter operator and k-CF functions are counterparts of the tangential Cauchy–Riemann operator and CR functions on the Heisenberg group in the theory of several complex variables,*** this paper,we introduce a Lie group that the Heisenberg group can be imbedded into and call it generalized complex *** investigate quaternionic analysis on the generalized complex *** also give the Penrose integral formula for k-CF functions and construct the tangential k-Cauchy-Fueter complex.

关键词： the generalized complex Heisenberg group the tangential k-Cauchy-Fueter type operator Penrose-type integral formula

Energy Transfer Pathways in Reaction Center upon Femtosecond Excitation of Accessory Bacteriochlorophylls

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Chinese Physics Letters 2001年第4期18卷 522-524页

作者： GUO Li-Jun MA Guo-Hong ZOU Yong-Long XU Chun-He LIU Ye MI Jun qian shi-xiong LIU Jian-Hua Department of Physics Fudan UniversityShanghai 200433 Shanghai Institute of Plant Physiology Chinese Academy of SciencesShanghai 200032

The energy transfer pathways from the excited accessorybacteriochlorophylls (B*) within native and modified (pheophytin-exchanged) reaction center isolated from Rhodobactersphaeroides (RS601) have been investigated by using the femtosecond pump-probe technique. For native RS601, B* decays with time constant of 240 fs, followed by a partial recovery of the ground state bleaching with time scale of about 2 ps. In modified RS601(Phe), however, B* decays with time constant of 800 fs for magic angle (54.7°) polarization configuration. In addition to the general assumption of energy transfer pathway from B* to the special pair P, an alternative pathway for energy transfer probably operates as well.

关键词： technique. decay excited