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Theoretical Study of Haloacetonitrile Anions： CH2XCN^- （X=F, Cl）

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Chinese Journal of Chemical Physics 2008年第3期21卷 255-262页

作者： xin-wen Zhang Mei Li shan-xi Tian Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technologyof China Hefei 230025 China Department of Chemical Physics University of Science and Technology of China Hefei 230026China

Haloacetonitrile anions CH2XCN- （X=F, Cl） were studied by HF-SCF, Becke3-LYP, and MP2 methods together with the Dunning＇s basis set aug-cc-PVTZ. The vertical electron attachments to the neutral are endothermic. The geometrically optimized CH2FCN^- is mainly a valence-bounded anion and CH2FCN→CH2CN＋F^- is a nonadiabatic dissociation. This theoretical study in good agreement with the experimental results shows that the Becke3-LYP method is reasonable in describing the electronic structures of anions and dissociative attachment dynamics, while significant differences between MP2 and Becke3-LYP results are shown for the dissociation potential curves of CH2ClCN→CH2CN＋Cl^-.

关键词： Haloacetonitrile Electron attachment Dissociation dynamics Electron correlation effect

Engineering Two-Atom Thermal Entanglement via Two-Photon Process

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Communications in Theoretical Physics 2004年第4X期42卷 524-528页

作者： GUOYan-Qing ZHOULing SONGHe-shan YIXue-xi DepartmentofPhysics DalianUniversityofTechnologyDalian116023China

We study that two atoms simultaneously interact with a single mode thermal field via different couplings and different spontaneous emission rates when two-photon process is involved. It is found that we indeed can employ the different couplings to produce the two-atom thermal entanglement in two-photon process. The different atomic spontaneous emission rates are also utilizable in generating thermal entanglement. We also investigate the effect of the can obtain a strong and steady entanglement.

关键词：双原子热纠缠双光子加工自发辐射量子信息谐振腔量子电动力学

Effects of the shape and size of rectangular inclusions on the fatigue cracking behavior of ultra-high strength steels

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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 360-364页

作者： Yan-ping Zeng Hong-mei Fan xi-shan xie School of Materials Science and Engineering University of Science and Technology Beijing

The fatigue cracking behavior of ultra-high strength steels containing rectangular inclusions of small sizes were investigated based on in situ observations by scanning electron microscopy （SEM）. The size and shape of rectangular inclusions affect markedly the initiation site and propagation path of a fatigue crack. Especially, the initiation site of a fatigue crack depends strongly on the angle between the long-axis of a rectangle inclusion and the loading direction, and the length/width ratio of this rectangle inclusion because the residual stress distribution fields vary with these conditions. The results coincide very well with those of finite element analysis.

关键词： high strength steel inclusions fatigue of materials crack initiation crack propagation

Influence of Femtosecond Laser Irradiation and Heat Treatment on Precipitation of Silver Nanoparticles in Glass

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Chinese Physics Letters 2003年第6期20卷 932-934页

作者： ZENGHui-Dan QIUJian-Rong JIANGxiong-Wei QUShi-Liang ZHUCong-shan GANFu-xi PhotoCraftProject ShanghaiInstituteofOpticsandFineMechanicsChineseAcademyofSciencesShanghai201800

Silver nanoparticles were precipitated inside an Ag2O-doped glass by femtosecond laser irradiation and successive heat treatment. The influence of heat treatment temperature on the precipitation of silver nanoparticles was investigated. Absorption spectra show that the femtosecond laser irradiation results in an apparent decrease of the treatment temperature for the precipitation of Ag nanoparticles. We demonstrate the control of precipitation, dissolution and growth of silver nanoparticles inside glass by changing the heat treatment temperature or using further femtosecond laser irradiation.

关键词： Silver nanoparticles

Molecular Dynamics Simulation Study of CIF in Water： Halogen Bonding Interaction in Liquid

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Chinese Journal of Chemical Physics 2017年第1期30卷 25-28,I0001页

作者： Yu-feng Ye Cen-feng Fu shan-xi Tian Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical Physics University of Science and Technology of China Hefei 230025 China

Does the halogen bonding interaction co-exist in liquid when it competes with the hydrogen bonding interaction？ The classical molecular dynamics simulations for the solvation properties of CLF molecule in water are performed with the Lennard-Jones plus Coulomb electrostatic potential parameters that are optimized with ab initio interaction energy calculations for the pre-reactive H2O-CLF complex. We find that the halogen bonding interactions occur between O and CL atoms and have the comparable strength and population with respect to the hydrogen bonding interactions of C1...H.

关键词： Halogen bonding interaction Molecular dynamics simulation C1F molecule Hydrogen bonding interaction Aqueous solution

Preparation and Characterization of Flame Retardant and Low Smoke Releasing Oil-resistant EVA/NBR Blends

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Chinese Journal of Polymer Science 2015年第4期33卷 554-563页

作者： Huan Zou Jun Sun xiao-yu Gu Peng Jiang xi-shan Liu 张胜 Key Laboratory of Carbon Fiber and Functional Polymers Ministry of EducationBeijing University of Chemical Technology

Nano-SiO2 and/or MoO3 were introduced to ethylene-vinyl acetate/nitrile butadiene rubber （EVA/NBR） blends containing magnesium hydroxide （MH） and red phosphorus （RP） to further improve the mechanical properties, oil resistance, smoke suppression and flame retardancy. The results indicated that the tensile strength and oil resistance were significantly improved by incorporating nano-SiO2. Smoke suppression tests for EVA/NBR blend samples showed that both nano-SiO2 and MoO3 can significantly reduce smoke release amount. The flammability characterization indicated that the blended sample with an LOI value of 33.0 could achieve V-0 level in the UL-94 test. Cone calorimetry test data showed the peak heat release rate was 67% lower than that for pure EVA/NBR. Thermal analysis showed that the presence of both nano-SiO2 and MoO3 was beneficial to promoting char formation of the EVA/NBR blends. Char residual analysis suggested that MoO3 aggregated in solid phase during combustion.

关键词： Ethylene-vinyl acetate/nitrile butadiene rubber Tensile properties Oil resistance Smoke suppression Flame retardancy.

Preparation of Titanium-silphenylene-siloxane Hybrid Polymers with High Refractive Index,Transmittance,and Thermal Stability

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Chinese Journal of Polymer Science 2020年第9期38卷 973-982,I0007页

作者： Dong Zhao Shu-xi shan Meng Zhang xiao-A Zhang Sheng-Ling Jiang Ya-Fei Lyu Key Laboratory of Carbon Fiber and Functional Polymers of Ministry of Education College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Vinyl-containingtitanium-silphenylene-sioxane oligomers(O1,O2,O3,andO4)withdifferent molar ratios of titanium to silicon were successfully synthesized in high yields by nonhydrolytic sol-gel reaction,and the obtained four oligomers were further crosslinked with methylphenyl hydro-silicone oil(4)to form corresponding polymers(P1,P2,P3,and P4)by hydrosilylation *** structures were characterized with spectroscopic characterization techniques including FTIR,1H-NMR,and Raman *** effect of titanium element on crosslinking behavior,thermal resistance,refractive index,transparency,thermal aging stability,glass transition temperature,and surface properties of the polymers were *** with titanium-free polymer P1,the thermal resistance,refractive index,and thermal aging stability of titanium-silphenylene-siloxane polymers(P2,P3,and P4)were significantly *** titanium-silphenylene-siloxane polymers achieved a high refractive index(n=1.580-1.584)and thermostability(Tsd>500℃).In thermal aging,the polymers exhibited superior performances with high optical transparency(~90%at 450 nm)and exhibited high thermal stability(~84%at 450 nm after thermal aging at 150℃for 120 h).These data indicate that the polymers have potential application in optical materials such as LED encapsulants.

关键词： Titanium-silphenylene-siloxane hybrid polymers High refractive index and transmittance Thermal stability

Mechanism of α-Cr precipitation and crystallographic relationships between α-Cr and δ phases in Inconel 718 alloy after long-time thermal exposure

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 312-317页

作者： Zhong-nan Bi Jian-xin Dong Mai-cang Zhang Lei Zheng xi-shan xie School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

To study the precipitation mechanism of α-Cr phase in Inconel 718 alloy, the samples after long-time aging at 650 and 677℃ were examined by microstructural observations and chemical phase analysis methods. Combining the thermodynamics and kinetics calculation results, α-Cr always precipitates in the vicinity of δ phase, because δ phase rejects Cr into the γ-matrix when growing. The selected area diffraction patterns confirm that the crystallographic relationships of α-Cr with 6 phase are （010）d/（1- 10）*** and [100]d/If 11 ]α-Cr- A graphic model is also presented to show the crystallographic relation between α-Cr and δ phases.

关键词： Inconel 718 precipitation mechanism crystallography thermodynamics kinetics

Interstellar Refractive Scintillation and Intraday Polarization Angle Swings

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Chinese Journal of Astronomy and Astrophysics 2005年第1期5卷 27-40页

作者： shan-JieQian xi-ZhenZhang A.Kraus NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 Max-Planck-InstitutfiirRadioastronomie aufdemHiigel6953121BonnGermany

Intraday polarization angle swings of ～180° observed in two sources (QSO0917+624 and QSO 1150+812) are discussed in the framework of refractive interstellar scintillationby a continuous interstellar medium. Model-fits to the I-, Q- and U- light curves were made for bothsources. It is shown that for the case of 0917+624 both the intraday intensity variations and thepolarization angle swing of ～180° could be explained consistently in terms of a four-componentmodel, which comprises one steady and two scintillating polarized components and one furthernon-polarized scintillating component. The polarization angle swing of ～180° observed in 1150+812,which occurred when the polarized flux density was almost constant, could not be explained in termsof refractive scintillation by a continuous medium and might be due to other mechanisms (e.g.,scintillation by interstellar clouds).

关键词： radio continuum galaxies polarization intraday variability scattering refractive scintillation quasars individual: QSO 0917+624 and 1150+812