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Chinese Physics B 2016年第6期25卷 416-425页

作者：杨荣唐斌高涛敖冰云 Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China College of Materials Science and Engineering Chongqing Jiaotong University Chongqing 400074 China Institute of Finance & Trade Chongqing City Management College Chongqing 401331 China Science and Technology on Surface Physics and Chemistry Laboratory P. O. Box 718-35 Mianyang 621907 China

Hybrid density functional theory is employed to systematically investigate the structural,magnetic,vibrational,thermodynamic properties of plutonium monocarbide（Pu C and Pu C0.75）.For comparison,the results obtained by DFT,DFT ＋ U are also *** Pu C and Pu C0.75,Fock-0.25 hybrid functional gives the best lattice constants and predicts the correct ground states of antiferromagnetic（AFM） *** calculated phonon spectra suggest that Pu C and Pu C0.75 are dynamically *** of the Helmholtz free energy ？F,internal energy ？E,entropy S,and constant-volume specific heat Cv of Pu C and Pu C0.75 are *** results are in good agreement with available experimental or theoretical *** for the chemical bonding nature,the difference charge densities,the partial densities of states and the Bader charge analysis suggest that the Pu–C bonds of Pu C and Pu C0.75 have a mixture of covalent character and ionic *** effect of carbon vacancy on the chemical bonding is also discussed in *** expect that our study can provide some useful reference for further experimental research on the phonon density of states,thermodynamic properties of the plutonium monocarbide.

关键词： hybrid functional DFT+U plutonium monocarbide

First-principles calculation of the electronic structure, chemical bonding, and thermodynamic properties of β-US_2

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Chinese Physics B 2015年第12期24卷 470-476页

作者：李世长郑远蕾马生贵高涛敖冰云 Institute of Atomic and Molecular Physics Sichuan University Science and Technology on Surface Physics and Chemistry Laboratory

The electronic structure, magnetic states, chemical bonding, and thermodynamic properties of β-US2 are investigated by using first-principles calculation through the density functional theory（DFT）＋U approach. The obtained band structure exhibits a direct band gap semiconductor at Γ point with a band gap of 0.9 e V for β-US2, which is in good agreement with the recent experimental data. The charge-density differences, the Bader charge analysis, and the Born effective charges suggest that the U–S bonds of the β-US2 have a mixture of covalent and ionic characters, but the ionic character is stronger than covalent character. The Raman-active, infrared-active, and silent modes at the Γ point are further assigned and discussed. The obtained optical-mode frequencies indicate that the three apparent LO–TO（longitudinal optical–transverse optical） splittings occur in B1 u, B2 u, and B3 umodes, respectively. Furthermore, the Helmholtz free energy ？F, the specific heat ？E, vibrational entropy S, and constant volume CVare studied over a range from 0 K-100 K. We expect that our work can provide some valuable information for further experimental investigation of the dielectric properties and the infrared reflectivity spectrum of uranium chalcogenide.

关键词： β-US2 magnetization chemical bonding thermodynamic properties

Density function theoretical study on the complex involved in Th atom-activated C–C bond in C2H6

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Chinese Physics B 2016年第6期25卷 172-178页

作者：王青青李鹏高涛王红艳敖冰云 Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China College of Physics and Electronic Engineering Shanxi University Taiyuan 030006 China School of Physical Science and Technology Southwest Jiaotong University Chengdu 610031 China Science and Technology on Surface Physics and Chemistry Laboratory P. O. Box 9071-35 Jiangyou 621907 China

Density functional theory（DFT） calculations are performed to investigate the reactivity of Th atom toward ethane C–C bond activation.A comprehensive description of the reaction mechanisms leading to two different reaction products is *** report a complete exploration of the potential energy surfaces by taking into consideration different spin *** addition,the intermediate and transition states along the reaction paths are ***,partial,and overlap population density of state diagrams and analyses are also ***,the natures of the chemical bonding of intermediate and transition states are studied by using topological method combined with electron localization function（ELF） and Mayer bond *** spectrum（IR） is obtained and further discussed based on the optimized geometries.

关键词： reaction mechanism Mayer bond order electron localization function density of states

Enhancement of hydrogenation kinetics and thermodynamic properties of ZrCo1-xCrx(x=0-0.1)alloys for hydrogen storage

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Chinese Physics B 2020年第8期29卷 543-552页

作者： Linling Luo Xiaoqiu Ye Guanghui Zhang Huaqin Kou Renjin Xiong Ge Sang Ronghai Yu Dongliang Zhao Science and Technology on Surface Physics and Chemistry Laboratory Mianyang 621907China Institute of Materials China Academy of Engineering PhysicsMianyang 621900China School of Materials Science and Engineering Beihang UniversityBeijing 100191China Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China

The vacuum arc melting method was used to prepare ZrCo1-xCrx(x=0,0.025,0.05,0.075,0.1)***,the crystal structure,hydrogenation kinetics,thermodynamic properties,and disproportionation performance of ZrCo1-xCrx(x=0-0.1)alloys were *** x-ray diffraction spectra demonstrated that ZrCo1-xCrx(x=0-0.1)alloys contained ZrCo and ZrCo2 phases,and their corresponding hydrides consisted of ZrCoH3 and ZrH *** activation behaviors of Cr-substituted samples were significantly *** activation time of ZrCo was 7715 s while that of ZrCo0.9Cr0.1 was 195 *** improvement of kinetics can be attributed to the catalytic hydrogenation of *** activation energy for the hydrogenation of ZrCo was 44.88-kJ·mol^-1 H2 and decreased to 40.34-kJ·mol^-1 H2 for *** plateau pressure and width of the pressure-composition-temperature curves decreased slightly as Cr content *** extent of disproportionation of ZrCo was 83.68%after being insulated at 798 K for 10 h and decreased slightly to 70.52%for *** improvement of anti-disproportionation performance can be attributed to increase in the activation energy of disproportionation from 167.46-kJ·mol^-1 H2 for ZrCo to 168.28-kJ·mol^-1 H2 for ZrCo0.95Cr0.05.

关键词： hydrogen storage ZrCo Cr substitution anti-disproportionation performance activation behaviors

First-Principles Study of Structural,Magnetic,Electronic and Elastic Properties of PuC_2

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Communications in Theoretical Physics 2016年第10期65卷 447-452页

作者： Rong Yang Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China College of Materials Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China Institute of Finance&Trade Chongqing City Management CollegeChongqing 401331China Science and Technology on Surface Physics and Chemistry Laboratory P.O.Box 718-35Mianyang 621907China

We perform first-principles calculations of crystal structure,magnetism,electronic structure,chemical bonding and elastic properties for PuC_2 using the standard local spin-density approximation(LSDA)+U *** use of the Hubbard term to describe the 5f electrons of plutonium is discussed according to the lattice parameters,magnetism and densities of *** calculated lattice constants and magnetism are in good agreement with the experimental data or other theoretical *** is shown that the total densities of states at the Fermi energy level mainly come from the contribution of narrow f *** Pu-C bonds of PuC_2 have a mixture of covalent character and ionic character,while covalent character is stronger than ionic *** C1-C2 bonding has strong covalent character because of sp^2 hybridization between C ***,the elastic properties of PuC_2 are *** hope that our results can provide a useful reference for further theoretical and experimental research on PuC_2.

关键词： PuC_2 LSDA+U chemical bonding elastic properties

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Li-Y-H三元氢化物的结构和稳定性研究

物理学报 2022年第1期71卷 262-271页

作者：李欢叶小球唐俊敖冰云高涛表面物理与化学重点实验室绵阳621907 四川大学原子与分子物理研究所成都610065

本文基于粒子群优化算法的结构预测方法结合第一性原理计算,研究了LiYH_(4),Li_(2)YH_(5)和Li_(3)YH_(6)在0-300 GPa压力范围内的晶体结构、电子结构、热力学和动力学稳定性.研究结果表明LiYH4-P4/nmm,Li_(2)YH_(5)-I4/mmm和Li_(3)YH_(6)-P4/nmm结构可分别在169-221 GPa,141-300 GPa和166-300 GPa压力范围内由LiH和YH3按一定配比加压合成.富氢化合物的超导电性研究成为近年来高温超导体研究领域的热点,该研究结果有希望为Li-Y-H三元体系氢化物的超导电性研究及实验合成提供数据支撑.

关键词：三元氢化物 Li-Y-H 结构预测第一性原理研究

维普期刊数据库博看期刊

Determination of activation energy of ion-implanted deuterium release from W–Y2O3

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Chinese Physics B 2020年第6期29卷 327-332页

作者： Xue-Feng Wang Ji-Liang Wu Qiang Li Rui-Zhu Yang Zhan-Lei Wang Chang-An Chen Chun-Rong Feng Yong-Chu Rao Xiao-Hong Chen Xiao-Qiu Ye School of Sciences and Research Center for Advanced Computation Xihua UniversityChengdu 610039China Science and Technology on Surface Physics and Chemistry Laboratory Mianyang 621907China

The retention and release of deuterium in W–2%Y2O3 composite materials and commercially pure tungsten after they have been implanted by deuterium plasma(flux ~ 3.71 × 1021 D/m2·s, energy ~ 25 eV, and fluence up to 1.3 × 1026D/m2)are studied. The results show that the total amount of deuterium released from W–2%Y2O3 is 5.23 × 1020 D/m2(2.5 K/min),about 2.5 times higher than that from the pure tungsten. Thermal desorption spectra(TDS) at different heating rates(2.5 K/min–20 K/min) reveal that both W and W–2%Y2O3 have two main deuterium trapped sites. For the low temperature trap, the deuterium desorption activation energy is 0.85 eV(grain boundary) in W, while for high temperature trap, the desorption activation energy is 1.57 eV(vacancy) in W and 1.73 eV(vacancy) in W–2%Y2O3.

关键词： metals and alloys plasma-based ion implantation thermal desorption diffusion in solid

Pd_(71.5)Cu_(12)Si_(16.5)金属玻璃的氢相关性能（英文）

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稀有金属材料与工程 2018年第12期47卷 3629-3633页

作者：杜晓清叶小球张桂凯任清波中国工程物理研究院材料研究所四川绵阳621908

通过电弧熔炼、铜辊甩带的方法制备了Pd_(71.5)Cu_(12)Si_(16.5)金属玻璃的宽带样品。通过常规X射线衍射仪和短波长X射线应力分析仪的X射线衍射谱确定了样品的完全非晶态结构。在室温、100kPa压力条件下,对样品进行了多次的吸、放氢循... 详细信息

通过电弧熔炼、铜辊甩带的方法制备了Pd_(71.5)Cu_(12)Si_(16.5)金属玻璃的宽带样品。通过常规X射线衍射仪和短波长X射线应力分析仪的X射线衍射谱确定了样品的完全非晶态结构。在室温、100kPa压力条件下,对样品进行了多次的吸、放氢循环实验。经过10次以上的循环后,样品没有发生破坏,表现出良好的抗氢脆性能。通过气体直接渗透的方法进一步测试了Pd_(71.5)Cu_(12)Si_(16.5)金属玻璃及其同成分晶态合金的氢渗透性能。在金属玻璃的过冷液相区温度范围内,其氢渗透率明显高于晶态相,这一结果由金属玻璃在该区间内的等温保持引入了更多的自由体积进行解释。

关键词：金属玻璃非晶态材料 X射线衍射氢脆氢渗透性能

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钛中氘致裂纹的原位研究

稀有金属材料与工程 2021年第2期50卷 389-395页

作者：叶小球肖瑶吴吉良杨蕊竹马邦俊罗德礼表面物理与化学重点实验室四川绵阳621907

采用热台显微镜(HSM)和压力-体积-温度(PVT)相结合的方法原位研究了钛在恒定温度及升温过程中的氘致裂纹(DIC)现象。结果表明:在550℃恒温吸氘(D2)过程中,钛片表面只出现很少的裂纹;而在由室温升温至550℃吸氘过程中钛表面出现了由边缘... 详细信息

采用热台显微镜(HSM)和压力-体积-温度(PVT)相结合的方法原位研究了钛在恒定温度及升温过程中的氘致裂纹(DIC)现象。结果表明:在550℃恒温吸氘(D2)过程中,钛片表面只出现很少的裂纹;而在由室温升温至550℃吸氘过程中钛表面出现了由边缘向中心部分扩展的环状裂纹。钛在升温过程中的形貌变化特征与"边缘进攻"模型符合;X射线光电子能谱(XPS)测试显示,由钛氧化物、碳化物和氮化物组成的钛表面钝化层在环状裂纹形成过程中发挥了重要作用。

关键词：储氢材料钛氘致裂纹动力学

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钚中氦行为研究进展

材料导报 2020年第11期34卷 11137-11144,11152页

作者：肖瑶黄理邱睿智叶小球敖冰云中国工程物理研究院绵阳621000

钚是一种应用广泛的核材料。作为放射性元素,钚会自发衰变成铀核,同时产生α粒子(氦核),高速运动的衰变产物在晶格中激发离位,产生缺陷。由于最外层是满电子结构,氦难溶于金属。因此,钚持续自发衰变会在材料中累积大量的晶格损伤;同时... 详细信息

钚是一种应用广泛的核材料。作为放射性元素,钚会自发衰变成铀核,同时产生α粒子(氦核),高速运动的衰变产物在晶格中激发离位,产生缺陷。由于最外层是满电子结构,氦难溶于金属。因此,钚持续自发衰变会在材料中累积大量的晶格损伤;同时由衰变产生的氦会在金属基体中与空位相结合,通过位错与晶界扩散,在基体中聚集、形核、长大,形成氦泡。含氦量的增加会使氦泡生长,但并不是无限制地长大;当氦含量很高时,氦泡会破裂,引起材料表面剥落;一定程度上,材料本身的性质决定了氦泡最后的大小。宏观上,氦的存在会使材料发生体积变化、延展性降低、脆性变大等物理老化现象,从而降低钚的使用性能、缩短其寿命。理解氦原子对钚结构性能的影响机制,探寻相应的抑制氦脆和氦损伤的有效措施,对钚材料老化效应的预测和评价具有重要的意义。目前,研究钚中的氦行为主要集中在实验和模拟两个方面。由于原材料本身的放射性和毒性,研究人员大多使用晶体结构、最外层电子结构或是某些力学性能与钚一致的模拟材料进行实验。研究发现,微观结构和成分的优化是调控钚抗老化的重要手段。通常,微观结构的变化中主要考察晶界和位错对材料中氦行为的影响,而成分的优化则是通过添加合金元素或改变相来进行研究。鉴于此,本文就氦对钚材料体积、电阻率、力学性能的影响,以及氦在钚中的微观行为进行了综述,比较了不同方法在钚中氦行为研究方面的适用性,指出了进一步构建氦的微观状态与宏观性能之间对应关系的必要性以及可能的研究方向。

关键词：钚氦脆老化辐照损伤