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Photoinduced Intramolecular Charge Transfer in Donor-acceptor Dyad and Donor-bridge-acceptor Triad

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Chinese Journal of Chemical Physics 2008年第2期21卷 111-117页

作者： Yong Ding Yuan-zuo li Feng-cai Ma Department of Physics Liaoning University Shenyang 110036 China Department of Physics Peking University Beijing 100871 China

The ground and excited state properties of the [60]fullerene, diphenylbenzothiadiazole-triphenylamine （PBTDP-TPA） dyad and fullerene-diphenylbenzothiadiazole-triphenylamine （fullerene-PBTDP-TPA） triad were investigated theoretically using density functional theory with B3LYP functional and 3-21G basis set and time-dependent density functional theory with B3LYP functional and STO-3G basis set as well as 2D and 3D real space analysis methods. The 2D site representation reveals the electron-hole coherence on excitation. The 3D transition density shows the orientation and strength of the transition dipole moment, and the 3D charge difference density gives the orientation and result of the intramolecular charge transfer. Also photoinduced intermolecular charge transfer （ICT） in PBTDP-TPA-fullerene triad are identified with 2D and 3D representations, which reveals the mechanisms of ICT in donor-bridge-acceptor triad on excitation. Besides that we also found that the direct superexchange ICT from donor to acceptor （tunneling through the bridge） strongly promotes the ICT in the donor-bridge-acceptor triad.

关键词： Donor-acceptor dyad Donor-bridge-acceptor triad Intramolecular charge transfer Superexchange

Anomalous Transport Characteristics of High Temperature Superconductors and Josephson Currents

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Communications in Theoretical Physics 2002年第3期38卷 379-384页

作者： liANG Fang-Ying li zuo-Hong Institution of Science and Technology for OPTO-Electronic Information Yantai University Yantai 26400 Shangdong Province China Institution of Science and Technology for OPTO-Electronic Information Yantai University Yantai 26400 Shangdong Province China

The transport characteristics of high temperature superconductor current and Josephson current is inves-tigated in the framework of the modified time-dependent Ginzburg-Landau model and the Lawrence-Doniach *** evaluated the vortex equation and found that the signs of the high temperature superconductor current and theJosephson current can reverse. Some explicit expressions for different cases are derived, which accord with experimentaldata.

关键词： superconductivity, junction, Josephson current

Minimal periodic solutions of first-order convex Hamiltonian systems with anisotropic growth

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Frontiers of Mathematics in China 2018年第5期13卷 1063-1073页

作者： Chungen liU li zuo Xiaofei ZHANG School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006 China School of Mathematics Nankai University Tianjin 300071 China

Based on the work of Clarke and Ekeland and using duality variational principle, we confirm the existence of minimal periodic solutions of some convex Hamiltonian systems with anisotropic growth.

关键词： Hamiltonian system minimal period Fenchel's transform subdifferential

The Distribution of DEN Infected People in Dushan and Xingyi Area of Yunnan-Guizhou Plateau,China

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Cellular & Molecular Immunology 2006年第6期3卷 473-476页

作者： Wei liu li zuo Yongbing Zhou Department of Immunology Guiyang Medical College Guiyang 550004 Guizhou China

The dengue viruses （DEN, genus Flavivirus, family Flaviviridae） are mosquito borne and have caused 100 million cases of dengue fever each year in most tropical and subtropical areas of the world. However, in the Southwest area of Yunnan-Guizhou Plateau, China, the previous work demonstrated that different geographic strains of Aedes albopictus were susceptible to dengue virus. In this study, we collected 456 sera samples from patients with fever and 994 sera samples from healthy population in Dushan and Xingyi area of Yunnan-Guizhou Plateau, China. All sera samples were tested for dengue IgG by enzyme-linked immunosorbent assay （EliSA）. Patients＇ sera samples were tested for dengue IgM and DEN antigen was checked in the sera of 6 from 456 samples with which C6/36 cell in culated by IFA. The results indicate that these patients with fever were infected with DEN-2 and suggest that DEN infection had existed in Dushan and Xingyi area of Yunnan-Guizhou Plateau, China.

关键词： dengue virus DHF IFA

Effects of metal binder on the microstructure and mechanical properties of Al2O3-based micro-nanocomposite ceramic tool material

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International Journal of Minerals,Metallurgy and Materials 2017年第7期24卷 826-832页

作者： Xiu-ying Ni Jun Zhao Jia-lin Sun Feng Gong zuo-li li Key Laboratory of High Efficiency and Clean Mechanical Manufacture of the Ministry of Education Shandong University Jinan 250061 China

The Al_2O_3-（W,Ti）C composites with Ni and Mo additions varying from 0vol% to 12vol% were prepared via hot pressing sintering under 30 MPa. The microstructure was investigated via X-ray diffraction（XRD） and scanning electron microscopy（SEM） equipped with energy dispersive spectrometry（EDS）. Mechanical properties such as flexural strength, fracture toughness, and Vickers hardness were also measured. Results show that the main phases A12O3 and（W,Ti）C were detected by XRD. Compound Mo Ni also existed in sintered nanocomposites. The fracture modes of the nanocomposites were both intergranular and transgranular fractures. The plastic deformation of metal particles and crack bridging were the main toughening mechanisms. The maximum flexural strength and fracture toughness were obtained for 9vol% and 12vol% additions of Ni and Mo, respectively. The hardness of the composites reduced gradually with increasing content of metals Ni and Mo.

关键词： ceramic matrix nanocomposite metal phase microstructure mechanical properties

Reinforcing effect of graphene on the mechanical properties of Al2O3/TiC ceramics

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1403-1411页

作者： zuo-li li Jun Zhao Jia-lin Sun Feng Gong Xiu-ying Ni Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education School of Mechanical EngineeringShandong UniversityJinan 250061China

Multilayer graphene(MLG)-reinforced Al_2O_3/TiC ceramics were fabricated through hot pressing sintering, and the reinforcing effect of MLG on the microstructure and mechanical properties of the composites was investigated by experiment and simulation. The simulation of dynamic crack initiation and propagation was investigated based on the cohesive zone method. The results show that the composite added with 0.2 wt% MLG has excellent flexural strength and high fracture toughness. The major reinforcing mechanisms are the synergistic effect by strong and weak bonding interfaces, MLG pull-out, and grain refinement resulting from the addition of MLG. In addition, the aggravating of crack deflection, branching, blunting, and bridging have indispensable contribution to the improvement of the as-designed materials.

关键词： mechanical properties ceramics graphene simulation interface

NLO Corrections of H_(TC)Π~0 and Π^+Π^- Pair Production at ILC in TC2 Model

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Communications in Theoretical Physics 2009年第8期52卷 311-317页

作者： QIAO Qing-Peng li zuo li Xue-Qian WANG Xue-Lei Department of Physics Nankai University Tianjin 300071 China Department of Physics Henan Normal University Xinxiang 453007 China

As well known, if the Higgs boson were not observed at LHC, the technicolor model would be the most favorable candidate responsible for the symmetry breaking. To overcome some defects in the previous model, some extended versions have been proposed. In the TC2 model typical signature is existence of heavy HTC and technipion ∏. A direct proof of validity of the model is to produce them at accelerator. Thus we study the production rates of e＋e^- → HTC∏^0 and e＋e^- → ∏＋∏- at ILC in the topcolor-assisted technicolor （TC2） model. In fact, there is a flood of models belonging to new physics, which can result in products with characteristics similar to HTC ＋ ∏ of the TC2 model. Therefore to distinguish this model from others one may need to investigate some details by calculating the cross section to NLO. We indeed find that the NLO corrections are significant, namely the ratio δ ≡（ σNLO - σLO）/σLO in e＋e- →HTC∏^0 exceeds 100% within a plausible parameter space.

关键词： TC2 top-pion top-higgs LOOPTOOLS

Simulation on venting process and valve opening control method for gas trunk pipelines

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Petroleum Science 2022年第6期19卷 3016-3028页

作者： li-li zuo An-Tai Jin Qian Chen Qin-Long Dong Yuan-Xin li Si-Rui Zhao National Engineering Laboratory for Pipeline Safety/Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum(Beijing)Beijing102249China Petro China Planning&Engineering Institute Beijing100083China National Petroleum and Natural Gas Pipe Network Group Beijing Pipeline Co. Ltd.Beijing100101China

Determining the venting time of a gas trunk pipeline segment provides an important basis for formulating an emergency plan in the advent of unexpected *** the natural gas venting process corresponds to the transient flow,it is necessary to establish a transient hydraulic-thermal simulation model in order to determine the venting *** this paper,based on two kinds of venting scenarios in which there is only one venting point in the venting system of a gas trunk pipeline segment—namely,where the venting point is either at one of the two ends or at the junction of two gas trunk pipeline segments—transient hydraulic-thermal simulation models are *** models consist of gas flow governing equations,the gas state equation,gas physical property equations,initial conditions,and appropriate boundary *** implicit central difference method is used to discretize the gas flow partial differential equations,and the trust-region-dogleg algorithm is used to solve the equations corresponding to each time step,in order to dynamically simulate the whole venting *** judgment condition for the end of the venting process is that the average pressure of gas trunk pipeline segment is less than 0.11 MPa(actual pressure).Comparing the simulation results of the proposed model with those of the OLGA software and real operational data,we find that the venting time error is less than 10%.On this basis,a venting valve opening control principle is proposed,which prevents the venting noise from exceeded the specified noise value(85 d B)in the venting design of domestic gas pipeline *** established calculation model for venting time(dynamic simulation model)for a gas trunk pipeline segment and the proposed opening control principle of venting valve provide reference for the optimal operation of gas pipeline venting systems.

关键词： Gas pipeline Venting time Transient simulation Implicit central difference method Valve Opening Control Method

Introduction of a New Method for Regulating Laves Phases in Inconel 718 Superalloy during a Laser-Repairing Process

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Engineering 2022年第9期16卷 239-246页

作者： Shang Sui Haosheng li zuo li Xuan Zhao liang Ma Jing Chen State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China

The morphology,size,and distribution of Laves phases have important influences on the mechanical properties of laser-repaired Inconel 718(IN718)*** to the deterioration of the substrate zone,the Laves phase in the laser cladding zone of IN718 superalloy cannot be optimized by a hightemperature solution *** this study,an in situ laser heat-treatment method was proposed to regulate the morphology and size of the Laves phase in the laser cladding zone of IN718 superalloy without impacting the substrate *** the in situ laser heat-treatment process,a laser was used to heat previously deposited layers with optimized manufacturing parameters.A thermocouple and an infrared camera were used to analyze thermal cycles and real-time temperature fields,*** and micro-segregations were observed by optical microscopy,scanning electron microscopy,and electron probe *** was found that the in situ laser heat treatment effectively changed the morphology and size of the Laves phase,which was transformed from a continuous striplike shape to a discrete granular *** effective temperature range and duration were the two main factors influencing the Laves phase during the in situ laser heat-treatment *** effective temperature range was determined by the laser linear energy density,and the peak temperature increased with the increase of the linear energy *** addition,the temperature amplitude could be reduced by simultaneously increasing the laser power and the scanning ***,a flow diagram was developed based on the in situ laser heat-treatment process,and the deposition of a single-walled sample with fine and granular Laves phases was detected.

关键词： Laser repair In situ laser heat treatment Inconel 718 alloy Laves phase