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BaNi0.1Fe1.9As2单晶的钉扎机制及涡旋相图

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低温物理学报 2017年第2期39卷 27-31页

作者：鲁俊超于景新河南工业大学理学院

本文中,我们通过磁-电阻测量研究了Tc=19.4K的BaNi0.1Fe1.9As2单晶中的涡旋玻璃-涡旋液体相变.根据修正过的涡旋玻璃理论,并通过选择合适的临界指数s和H0,我们对所有的ρ(H,T)电阻曲线进行了标度,并得到了很好的结果.基于涡旋玻璃温度Tg... 详细信息

本文中,我们通过磁-电阻测量研究了Tc=19.4K的BaNi0.1Fe1.9As2单晶中的涡旋玻璃-涡旋液体相变.根据修正过的涡旋玻璃理论,并通过选择合适的临界指数s和H0,我们对所有的ρ(H,T)电阻曲线进行了标度,并得到了很好的结果.基于涡旋玻璃温度Tg,涡旋维度转变温度T~*和上临界磁场Hc2,我们得到了H⊥c和H//c两个磁场方向的涡旋相图.结果表明,磁场低于和高于5T,钉扎机制由单涡旋钉扎和集体蠕动共存转变为集体蠕动.

关键词：铁基超导体磁-电阻钉扎相变

沸石分子筛对CH_(4)/H_(2)的吸附与分离性能

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物理学报 2021年第15期70卷 231-240页

作者：袁俊鹏刘秀英李晓东于景新河南工业大学理学院郑州450000

基于分子模拟的高通量计算方法,通过对199个沸石结构特征和吸附分离性能之间的关联性研究,发现具有超微孔结构的沸石材料对CH_(4)分子有良好的吸附分离性能,等摩尔CH_(4)/H2混合组份的CH_(4)吸附选择性和单组份的CH_(4)吸附量之间存在... 详细信息

基于分子模拟的高通量计算方法,通过对199个沸石结构特征和吸附分离性能之间的关联性研究,发现具有超微孔结构的沸石材料对CH_(4)分子有良好的吸附分离性能,等摩尔CH_(4)/H2混合组份的CH_(4)吸附选择性和单组份的CH_(4)吸附量之间存在明显的线性关系.通过使用巨正则蒙特卡罗模拟方法,获得了3个孔道形沸石对CH_(4)和H2的吸附等温线和等量吸附热等物理量.结果表明在相同外界环境下,孔道形沸石的孔结构(表面积和孔体积)对CH_(4)吸附量的影响高于能量效应(吸附热).结合甲烷蒸汽重整制氢的工业背景,进一步研究了CH_(4)/H2混合体系在不同组份下的分离选择性能,结果表明,超微孔沸石材料对CH_(4)的吸附选择性与体相压力和进料比无关.通过气体分子的质心分布密度发现,CH_(4)在孔道形沸石中优先占据更小孔窗的空间,而H2的分布范围更大但是未存在明显的优先吸附位点.

关键词：沸石分子筛高通量计算巨正则蒙特卡罗模拟吸附分离

Phase transition and thermodynamic properties of TiO_2 from first-principles calculations

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Chinese Physics B 2009年第1期18卷 269-274页

作者：于景新傅敏姬广富陈向荣 School of Physical Science and Technology Sichuan University Laboratory for Shock Wave and Detonation Physics Research Institute of Fluid PhysicsChinese Academy of Engineering Physics International Centre for Materials Physics Chinese Academy of Sciences

The pressure induced phase transitions of TiO2 from anatase to columbite structure and from rutile to columbite structure and the temperature induced phase transition from anatase to rutile structure and from columbite to rutile structure are investigated by ab initio plane-wave pseudopotential density functional theory method （DFT）, together with quasi-harmonic Debye model. It is found that the zero-temperature transition pressures from anatase to columbite and from rutile to columbite are 4.55 GPa and 19.92 GPa, respectively. The zero-pressure transition temperatures from anatase to rutile and from columbite to rutile are 950 K and 1500 K, respectively. Our results are consistent with the available experimental data and other theoretical results. Moreover, the dependence of the normalized primitive cell volume V/Vo on pressure and the dependences of thermal expansion coefficient α on temperature and pressure are also obtained successfully.

关键词： local density approximation transition phase thermodynamic property TiO2

基于工作过程的中职项目化课程教学的组织与实施——以“LED驱动电路”为例

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中文科技期刊数据库（全文版）教育科学 2021年第3期 372-374,376页

作者：于景新中山市第一职业技术学校广东中山528400

中职以培养产业基础技能型人才为主要目标,针对这个特点,对“LED驱动电路”课程进行基于工作过程的项目化课程教学研究。通过对工厂企业关于LED驱动电源产品的分析研究,确定典型工作任务,结合项目化课程教学的思路,在基于工作过程的基础... 详细信息

中职以培养产业基础技能型人才为主要目标,针对这个特点,对“LED驱动电路”课程进行基于工作过程的项目化课程教学研究。通过对工厂企业关于LED驱动电源产品的分析研究,确定典型工作任务,结合项目化课程教学的思路,在基于工作过程的基础上,确定教学项目,分析教学项目,自编项目教学教材,通过过程监督考核和期末理论及实操考核,让学生在“做中学,学中做”,使学生在掌握基本理论知识的同时,具备相应的基本专业技能。实践证明,基于工作过程的LED驱动电路项目化课程教学,能激发学生的学习兴趣和积极性,促进学生自主学习能力,提高了教学效果。

关键词：中职工作过程项目化教学 LED驱动电路

Stability of conductance oscillations in carbon atomic chains

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Chinese Physics B 2015年第6期24卷 540-544页

作者：于景新侯志伟刘秀英 College of Science Henan University of Technology

The conductance stabilities of carbon atomic chains （CACs） with different lengths are investigated by performing the- oretical calculations using the nonequilibrium Green＇s function method combined with density functional theory. Regular even-odd conductance oscillation is observed as a function of the wire length. This oscillation is influenced delicately by changes in the end carbon or sulfur atoms as well as variations in coupling strength between the chain and leads. The lowest unoccupied molecular orbital in odd-numbered chains is the main transmission channel, whereas the conductance remains relatively small for even-numbered chains and a significant drift in the highest occupied molecular orbital resonance to- ward higher energies is observed as the number of carbon atoms increases. The amplitude of the conductance oscillation is predicted to be relatively stable based on a thiol joint between the chain and leads. Results show that the current-voltage evolution of CACs can be affected by the chain length. The differential and second derivatives of the conductance are also provided.

关键词： electronic transport density functional theory non-equilibrium Green's function carbon atomicchains

Theoretical study of molecular hydrogen and spiltover hydrogen storage on two-dimensional covalent-organic frameworks

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Chinese Physics B 2014年第6期23卷 493-500页

作者：刘秀英何杰于景新栗正新樊志琴 College of Science Henan University of Technology School of Material Science and Engineering Henan University of Technology

Molecular hydrogen and spiltover hydrogen storages on five two-dimensional （2D） covalent-organic frameworks （COFs）（PPy-COF, TP-COF, BTP-COF, COF-18 A, and HHTP-DPB COF） are investigated using the grand canonical Monte Carlo （GCMC） simulations and the density functional theory （DFT）, respectively. The GCMC simulated results show that HHTP-DPB COF has the best performance for hydrogen storage, followed by BTP-COF, TP-COF, COF-18 A, and PPy-COE However, their adsorption amounts at room temperature are all too low to meet the uptake target set by US Department of Energy （US-DOE） and enable practical applications. The effects of pore size, surface area, and isosteric heat of hydrogen on adsorption amount are considered, which indicate that these three factors are all the important factors for determining the H2 adsorption amount. The chemisorptions of spiltover hydrogen atoms on these five COFs represented by the cluster models are investigated using the DFT method. The saturation cluster models are constructed by considering all possible adsorption sites for these cluster models. The average binding energy of a hydrogen atom and the saturation hydrogen storage density are calculated. The large average binding energy indicates that the spillover process may pro- ceed smoothly and reversibly. The saturation hydrogen storage density is much larger than the physisorption uptake of H2 molecules at 298 K and 100 bar （1 bar = 105 Pa）, and is close to or exceeds the 2010 US-DOE target of 6 wt% for hydrogen storage. This suggests that the hydrogen storage capacities of these COFs by spillover may be significantly enhanced. Thus 2D COFs studied in this paper are suitable hydrogen storage media by spillover.

关键词： hydrogen spillover covalent-organic frameworks hydrogen storage grand canonical Monte Carlo simulation

First-principles calculations for elastic properties of rutile TiO_2 under pressure

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Chinese Physics B 2008年第6期17卷 2216-2221页

作者：朱俊于景新王艳菊陈向荣经福谦 College of Physical Science and Technology Sichuan University Institute of Atomic and Molecular Physics Sichuan University Laboratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics

This paper studies the equilibrium structure parameters and the dependences of the elastic properties on pressure for rutile TiO2 by using the Cambridge Serial Total Energy Package （CASTEP） program in the frame of density functional theory. The obtained equilibrium structure parameters, bulk modulus B0 and its pressure derivative B′0 are in good agreement with experiments and the theoretical results. The six independent elastic constants of rutile TiO2 under pressure are theoretically investigated for the first time. It is found that, as pressure increases, the elastic constants C11, C33, C66, C12 and C13 increase, The variation of elastic constant C44 is not obvious and the anisotropy will weaken.

关键词： density functional theory elastic properties TiO2

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金属有机骨架中的水稳定性和吸附性能研究

化工新型材料 2017年第8期45卷 219-221页

作者：刘秀英于景新李晓东河南工业大学理学院郑州450000

金属有机骨架(MOFs)是一类新型的多孔纳米材料,由金属团簇和有机配体自组装而成。由于具有超高的表面积、可控的孔尺寸和可调的化学环境等优点,使其在空气净化、化学传感、气体存储、催化和CO2捕捉等方面表现出非常好的应用前景。然而... 详细信息

金属有机骨架(MOFs)是一类新型的多孔纳米材料,由金属团簇和有机配体自组装而成。由于具有超高的表面积、可控的孔尺寸和可调的化学环境等优点,使其在空气净化、化学传感、气体存储、催化和CO2捕捉等方面表现出非常好的应用前景。然而水稳定性一直是阻碍其工业化应用的瓶颈,所以研究MOFs和水的相互作用及MOFs的水解机理具有非常重要的意义。主要从MOFs水稳定性的研究方法,影响因素,如何增强MOFs的抗水性和有关MOFs水稳定性研究的最新动态等方面进行了详细论述,并指出了当前存在的问题和今后的发展方向。

关键词：金属有机骨架吸附水稳定性

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成长之歌

校园文苑（小学版） 2004年第12期 14-15页

作者：于景新张乃增山东省龙口市经济开发区圆璧张完小学五年级 265716