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Investigation of multilevel ion-pairing effect of triferrocenylmethane in organic phase

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Chinese Chemical Letters 2014年第10期25卷 1379-1381页

作者： De-bo xiang Hui-bo Shao Key Laboratory of Cluster Science(Ministry of Education of China) School of ChemistryBeijing Institute of Technology China Aviation Lithium Battery Co. Ltd.

The intramolecular electronic communication and multilevel ion-pairing effect of triferrocenylmethane（TriFcM） in organic phase was studied with the ＂thin-layer electrochemistry＂ *** pairs of symmetric peaks in cyclic voltammetry of TriFcM correspond to three one-electron electrochemical reaction processes and indicate strong intramolecular electronic communication,which could be used to study the multilevel ion-pairing *** different formation constants of ion-pairs between the three ferroceniums of TriFcM and perchlorate in thin organic film were obtained and compared.

关键词： Triferrocenylmethane Thin-layer electrochemistry Intramolecular electronic communication Multilevel ion-pairing effect

Gamete Recognition in Higher Plants:An Abstruse but Charming Mystery

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Journal of Integrative Plant Biology 2008年第7期50卷 868-874页

作者： Xiong-bo Peng Meng-xiang Sun Key Laboratory of Ministry of Education for Plant Developmental Biology College of Life Sciences Wuhan University Wuhan 430072 China

Although much effort has been made to uncover the mechanism underlying double fertilization, little knowledge has been acquired for understanding the molecular base of gamete recognition, mainly because of technical limitations. Still, progress has been made in terms of the mechanism, including the identification of candidate molecules that are involved in gamete recognition in angiosperms. New cues for gamete recognition have been found by the successful separation of the gametes and construction of gamete-specific cDNA libraries in several species, and the application of molecular approaches for studying this process by mutations. Thus, the topic is considered an abstruse but charming mystery.

关键词： central cell egg cell fertilization gamete recognition sperm cell.

Convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides from (E)-4-(2-bromovinyl)phenyl acetate

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Chinese Chemical Letters 2009年第5期20卷 545-548页

作者： Yu bo Jiang Chun xiang Kuang Department of Chemistry Tongji University Siping Road 1239 Shanghai 200092 China

A convenient one-pot synthesis of functionalized （E）-2-arylvinyl bromides was achieved by microwave-induced deacetylation and subsequent acylation using dicyclohexyl carbodiimide （DCC） and dimethylamino-pyridine ... 详细信息

关键词： One-pot synthesis (E)-2-Arylvinyl bromide Acylation Deacetylation

Density Functional Theory Study on Spin States of LaCoO3 at Room Temperature

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Chinese Journal of Chemical Physics 2014年第3期27卷 274-278页

作者： xiang-bo Zhang Gang Fu Hui-lin Wan State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College ofChemistry & Chemical Engineering Xiamen University Xiamen 361005 China

The electronic structure of the perovskite LaCoO3 at room temperature structure （293 K） was calculated by using PBE, PBE＋U and HSE. Different spin configurations have been considered. Our calculations showed that the choice of the Hubbard U parameter in DFT＋U and mixing factor α in HSE significantly influenced the band gap as well as relative energies. For the spin exited states, the optimal value for U and α were 3.0 eV and 0.05, respectively. Our calculation also emphasized that when U〉5.0 eV, PBE＋U would lead to unreasonable electronic structure and energy order.

关键词： Perovskite LaCoO3 Density functional theory

Fallback Disk-Involved Spin-Down of Young Radio Pulsars

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Chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 487-494页

作者： Zi-bo Jiang xiang-Dong Li Department of Astronomy Nanjing University Nanjing 210093

Disks originating from supernova fallback have been suggested to surround young neutron stars. Interaction between the disk and the magnetic field of the neutron star may considerably influence the evolution of the star through the so called propeller effect. There are many controversies about the efficiency of the propeller mechanism proposed in the literature. We investigate the faUback diskinvolved spin-down of young pulsars. By comparing the simulated and measured results of pulsar evolution, we present some possible constraints on the propeller torques exerted by the disks on neutron stars.

关键词： stars: magnetic fields - stars: neutron - pulsars: individual: PSRs B0532+21 B0833+45 B0540-69 B1509-58

Mesoscopic modelling of UHPCC material under dynamic tensile loadings

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Defence Technology（防务技术） 2023年第5期23卷 75-91页

作者： xiang-zhen Kong Shang-bin Yang Tao Zhang Qin Fang Heng-bo xiang Rui-wen Li Engineering Research Centre for Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityJiangsu Nanjing211189China State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLAJiangsu Nanjing210007China Research Institute for National Defense Engineering of Academy of Military Science PLALuoyang471023China School of Civil Engineering and Architecture Xi'an University of TechnologyXi'an710048China

This paper presents a new 3D mesoscopic model of ultra-high performance cement-based composite(UHPCC)to investigate its dynamic tensile *** this model,the UHPCC is regarded as a two-phase material composed of cementitious matrix and randomly distributed *** model is established using the commercial software LS-DYNA and involves generating the randomly distributed fiber elements with considerations of diameter,length,orientation and volume fraction,and then fully constraining them with the *** particular,to capture the slipping effect between fibers and matrix that has a strong influence on the dynamic tensile behavior,the fibers are modelled by a fictitious material represented by the load-slip *** strain-rate effect of slipping force neglected in most of previous studies is considered by calibrating constitutive parameters of the fictitious material under different strain-rates based on the single fiber pullout ***,the 3D mesoscopic model is validated against three sets of tension-dominated experiments covered a wide range of loading *** predictions demonstrate that strain-rate effect of slipping force must be considered,and the neglect of it may lead to a great underestimation of the dynamic tensile strength of UHPCC material and would unavoidably underestimate the blast resistance of UHPCC components.

关键词： UHPCC Dynamic tensile behavior Mesoscopic model Strain-rate effect Impact and blast loadings

Modeling the blast load induced by a close-in explosion considering cylindrical charge parameters

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Defence Technology（防务技术） 2023年第6期24卷 83-108页

作者： Yi Fan Li Chen Zhan Li Heng-bo xiang Qin Fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of the PLANanjingJiangsu210007China Engineering Research Center of Safety and Protection of Explosion&Impact of the Ministry of Education Southeast UniversityNanjingJiangsu211189China

Structural damage is significantly influenced by the various parameters of a close-in *** establish a close-in blast loading model for cylindrical charges according to these parameters,a series of field experiments and a systematic numerical analysis were conducted.A high-fidelity finite element model developed using AUTODYN was first validated using blast data collected from field tests conducted in this and previous studies.A quantitative analysis was then performed to determine the influence of the charge shape,aspect ratio(length to diameter),orientation,and detonation configuration on the characteristics and distributions of the blast loading(incident peak overpressure and impulse)according to scaled *** results revealed that the secondary peak overpressure generated by a cylindrical charge was mainly distributed along the axial direction and was smaller than the overpressure generated by an equivalent spherical *** effects of charge shape on the blast loading at 45°and 67.5°in the axial plane could be neglected at scaled distances greater than 2 m/kg^(1/3);the effect of aspect ratios greater than 2 on the peak overpressure in the 90°(radial)direction could be neglected at all scaled distances;and double-end detonation increased the radial blast loading by up to 60%compared to singleend ***,an empirical cylindrical charge blast loading model was developed considering the influences of charge aspect ratio,orientation,and detonation *** results obtained in this study can serve as a reference for the design of blast tests using cylindrical charges and aid engineers in the design of blast-resistant structures.

关键词： Cylindrical charge Secondary peak overpressure Aspect ratio Orientation Detonation initiation point Blast loading model

Characteristics of Mechanical Properties and Microstructure for 316L Austenitic Stainless Steel

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Journal of Iron and Steel Research International 2011年第11期18卷 53-59页

作者： SONG Ren-bo xiang Jian-ying HOU Dong-po School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

A comparative study on mechanical properties and microstructure of 316L austenitic stainless steel between solution treated specimen and hot rolled specimen was conducted. After a specimen was subjected to solution treatment at 1 050 ℃ for 6 min, its mechanical properties were determined through tensile and hardness tests. Based on the true stress vs true strain and engineering stress vs engineering strain flow curves, the work hardening rate has been explored. The results show that the solution treated specimen has an excellent combination of strength and elongation, and that this steel is easy to work-hardening during deformation. Optical microscope, scanning electron micro- scope, transmission electron microscope and X-ray diffraction examinations were conducted, these reveal that twins in 316L austenitic stainless steel can be divided into suspended twin and transgranular twin which have different for mation mechanisms in growth, and that the deformation induced martensite nucleated and grown in the shear band intersections can be observed, and that the fracture surfaces are mainly composed of dimples and exhibit a tough fracture character.

关键词： 316L mechanical property twin martensite fracture morphology

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Longevity Chance

Journal of Innovative Optical Health Sciences 2014年第2期7卷 18-23页

作者： Timon Cheng-Yi Liu Ling Zhu xiang-bo Yang Laboratory of Laser Sports Medicine South China Normal University GuangzhouGD510006P.R.China

Britton Chance pursued his research and sailing until his death at age *** 100th anniversary was memorialized in this paperfrom longevity *** ielong work was very *** was very *** aging was very *** has lived a longev... 详细信息

关键词： Aging exercise work redundancy photobiomodulation.