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Chinese Physics Letters 2015年第1期32卷 158-161页

作者：何强郭永权 School of Energy Power and Mechanical Engineering North China Electric Power University

The crystal structures and magnetic properties of novel Eu TrGa3-r （T=Pd, It, Rh） in termetallic compounds are investigated by using powder x-ray diffraction and magnetic measurements. EuTrGa3-r crystallizes in orthorhombic structure with space group of Cmcm and Z = 4. There are four kinds of nonequivalent 4c crystal positions in EuTrGaa-r unit cell, which are occupied by 4Eu, 4GaⅠ, 4（GaⅡ, T） and 4GaⅢ, respectively. EuTrGa3-r ex- hibits the complex magnetic states in low-temperature regime, with the three-, two- and one-antiferromagnetic transitions occurring for T=Ir, T=Rh and T=Pd, respectively. It might be due to the Kondo effect： a localized antiferromagnetic interaction of the isolated impurity spins with the surrounding conduction electrons at low-temperature regime.

关键词： Pd Ga Structures and Magnetic Properties of Europium-Transition Metal-Gallium Ternary Intermetallic Compounds with 1 Type Eu

Synthesis, structure, optical, and electric properties of Ce-doped CuInTe_2 compound

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Chinese Physics B 2014年第12期23卷 469-475页

作者：付丽郭永权 School of Energy Power and Mechanical Engineering North China Electric Power University

Ce-doped Cu In Te2（CICT） semiconducting compounds are successfully synthesized. The phase structures, optical,and electric properties are investigated using powder X-ray diffraction（XRD）, field emission scanning electron microscopy（FESEM）, X-ray photoelectron spectrometer（XPS）, Raman spectrometer, ultraviolet and visible spectrophotometer（UVVis）, and a standard four-probe method. Cu In1-xCex Te2 crystallizes into a tetragonal structure with predominant orientation along the [112] direction. The lattice parameters are a = 6.190（6） A–6.193（0） A and c = 12.406（5） A–12.409（5） A. Ce prefers to occupy the 4b crystal position. According to the analysis of XPS spectra, Ce shows the mixture of valences 4＋and 3＋. Raman spectra reveal that the photon vibrating model in the CICT follows A1 mode in a wavenumber range of123 cm^-1–128 cm^-1. UV-Vis spectra show that the band gap Eg values before and after 0.1 mole Ce doped into Cu In Te2 are 1.28 e V and 1.16 e V, respectively. It might be due to the mixture of valences for Ce. Ce doped into Cu In Te2 still shows the semiconductor characteristics.

关键词： CuIn1-xCexTe2 chalcopyrite Raman spectrum band gap semiconductor

Correlation between valence electronic structure and magnetic properties in RCo_5(R=rare earth) intermetallic compound

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Chinese Physics B 2016年第6期25卷 165-171页

作者：薛智琴郭永权 North China Electric Power University School of Energy Power and Mechanical Engineering

The magnetisms of RCo5（R = rare earth） intermetallics are systematically studied with the empirical electron theory of solids and molecules（EET）.The theoretical moments and Curie temperatures agree well with experimental ones.The calculated results show strong correlations between the valence electronic structure and the magnetic properties in RCo5 intermetallic compounds.The moments of RCo5 intermetallics originate mainly from the 3d electrons of Co atoms and 4f electrons of rare earth,and the s electrons also affect the magnetic moments by the hybridization of d and s electrons.It is found that moment of Co atom at 2c site is higher than that at 3g site due to the fact that the bonding effect between R and Co is associated with an electron transformation from 3d electrons into covalence electrons.In the heavy rare-earth-based RCo5 intermetallics,the contribution to magnetic moment originates from the 3d and 4f electrons.The covalence electrons and lattice electrons also affect the Curie temperature,which is proportional to the average moment along the various bonds.

关键词： EET theory electronic structure Curie temperature RCo5 intermetallics

超临界二氧化碳增压流化床燃煤发电系统方案及特性研究

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中国电机工程学报 2023年第17期43卷 6698-6708页

作者：伍权国家能源集团新能源技术研究院有限公司北京市昌平区102209

增压流化床炉(pressurized fluidized bed combustion boiler,PFBCB)超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))循环燃煤发电系统具备实现发电系统整体小型化与提高发电效率的潜力。围绕S-CO_(2)循环应用于燃煤发电领域面临的烟气热能全温区吸收这一共性问题,该文基于再热再压缩循环(Recompression cycle with reheating,RC+RH)提出两类耦合增压流化床炉的S-CO_(2)燃煤发电系统,可分别称为PFBCB-(RC+RH+RC)和PFBCB-(RC+RH),同时提出应用空气压缩机燃气轮机(air compressor-gas turbine,AC-GT)系统替代常压锅炉空气预热器系统的方案。根据计算可知,方案PFBCB-(RC+RH+RC)的效率低于PFBCB-(RC+RH),因为后者取消了RC底循环,因此系统布置更为简单,效率更高。但方案PFBCB-(RC+RH+RC)的炉内压力可维持在1~2MPa,而方案PFBCB-(RC+RH)炉内压力可达2.8~4.5MPa,故从锅炉侧看,前者更容易实施。此外,PFBCB-(RC+RH)系统可通过高压运行AC-GT,实现热能的回收,可有效解决余热问题。当主气温度处于620℃/30MPa时,该系统的发电效率为47.97%,当主气温度处于700℃/35MPa时,系统的发电效率为51.15%,体现出明显的效率优势。

关键词：超临界二氧化碳循环增压流化床锅炉燃煤发电余热吸收

Correlation between electronic structure and energy band in Eu-doped CuInTe_2 semiconductor compound with chalcopyrite structure

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Chinese Physics B 2017年第10期26卷 157-164页

作者：王泰郭永权李帅 School of Energy Power and Mechanical Engineering North China Electric Power University

The Eu-doped Cu（In, Eu）Te2 semiconductors with chalcopyrite structures are promising materials for their applications in the absorption layer for thin-film solar cells due to their wider band-gaps and better optical properties than those of CuInTe2. In this paper, the Eu-doped CuInTe2 （CuIn1-xEuxTe2, x = 0, 0.1, 0.2, 0.3） are studied systemically based on the empirical electron theory （EET）. The studies cover crystal structures, bonding regularities, cohesive energies, energy levels, and valence electron structures. The theoretical values fit the experimental results very well. The physical mechanism of a broadened band-gap induced by Eu doping into CuInTe2 is the transitions between different hybridization energy levels induced by electron hopping between s and d orbitals and the transformations from the lattice electrons to valence electrons for Cu and In ions. The research results reveal that the photovoltaic effect induces the increase of lattice electrons of In and causes the electric resistivity to decrease. The Eu doping into CuInTe2 mainly influences the transition between different hybridization energy levels for Cu atoms, which shows that the 3d electron numbers of Cu atoms change before and after Eu doping. In single phase CuIn1-xEuxTe2, the number of valence electrons changes regularly with increasing Eu content, and the calculated band gap Eg also increases, which implies that the optical properties of Eu-doped CuIn1-xEuxTe2 are improved.

关键词： CuIn1-xEuxYe2 EET solar cells valence electronic structures band gap

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同归殊途：论信息技术对政府治理创新的促进

科学学研究 2024年

作者：张权北京大学马克思主义学院

信息技术促进政府治理创新是国家治理现代化视阈下的一个重要命题。既有相关研究侧重介绍了信息技术发挥作用的方式和效果，却并未充分阐明“促进”本身是如何发生。针对这一问题，本文从学界对因果关系的不同理解出发，基于变量类型构... 详细信息

信息技术促进政府治理创新是国家治理现代化视阈下的一个重要命题。既有相关研究侧重介绍了信息技术发挥作用的方式和效果，却并未充分阐明“促进”本身是如何发生。针对这一问题，本文从学界对因果关系的不同理解出发，基于变量类型构建了一个关于信息技术促进政府治理创新的理论模型，然后以此“促进”模型为框架，结合现实案例和经验材料进行了系统讨论。研究认为，信息技术之于政府治理创新，可以起到建构（作为自变量）、催化（作为调节变量）、桥接（作为中介变量）、协同（作为协变量）、触发（作为工具变量）等五种作用。展望未来，可以关注创新发生的具体情境，就“什么条件下会发生哪种促进”的问题开展后续研究。

关键词：信息技术政府治理创新促进因果关系变量类型

经由氮杂邻联烯醌中间体合成轴手性化合物的研究进展

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有机化学 2024年第1期44卷 159-172页

作者：姜权彬中山大学化学学院广州510006

轴手性化合物不仅是不对称合成领域重要的催化剂和配体,许多天然产物和药物也是轴手性化合物.因此,发展轴手性化合物的高效合成方法是有机化学的重要研究课题.相对已经被广泛研究的邻联烯醌中间体,基于氮杂邻联烯醌中间体的不对称催化... 详细信息

轴手性化合物不仅是不对称合成领域重要的催化剂和配体,许多天然产物和药物也是轴手性化合物.因此,发展轴手性化合物的高效合成方法是有机化学的重要研究课题.相对已经被广泛研究的邻联烯醌中间体,基于氮杂邻联烯醌中间体的不对称催化反应近年来才受到人们的关注,研究相对较少,有着很大的发展空间.总结了经由氮杂邻联烯醌中间体构建轴手性化合物的研究进展,介绍了反应范围、机理和合成应用.最后对该研究领域的发展前景进行了总结和展望.

关键词：氮杂邻联烯醌中间体轴手性化合物不对称催化

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过渡期生长激素缺乏症的管理

中国当代儿科杂志 2024年第3期26卷 224-229页

作者：成胜权空军军医大学西京医院儿科陕西西安710032

随着对生长激素缺乏症认识的不断深入,临床逐渐重视过渡期生长激素缺乏症(transition growth hormone deficiency,TGHD)的管理。TGHD诊治不足是主要的临床痛点,为规范TGHD诊治,国内外已发布了相关指南/共识。该文结合指南/共识和现有临... 详细信息

随着对生长激素缺乏症认识的不断深入,临床逐渐重视过渡期生长激素缺乏症(transition growth hormone deficiency,TGHD)的管理。TGHD诊治不足是主要的临床痛点,为规范TGHD诊治,国内外已发布了相关指南/共识。该文结合指南/共识和现有临床研究,总结了TGHD的评估、诊断、治疗和临床挑战,以期优化和进一步改善TGHD临床诊治和管理。

关键词：生长激素缺乏症过渡期疾病管理重组人生长激素

基于连续弹性基础梁模型的扣件动刚度测试方法

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中国铁道科学 2022年第1期43卷 38-43页

作者：闫子权高速铁路轨道技术国家重点实验室北京100081 中国铁道科学研究院集团有限公司铁道建筑研究所北京100081

为确定服役状态下的轨道扣件动刚度,将钢轨视为置于连续弹性基础上的简支梁,推导扣件动刚度计算式,提出基于连续弹性基础梁模型的扣件动刚度测试方法,对某服役状态下的高铁线路轨道扣件动刚度进行测试。结果表明:扣件动刚度由钢轨1阶弯... 详细信息

为确定服役状态下的轨道扣件动刚度,将钢轨视为置于连续弹性基础上的简支梁,推导扣件动刚度计算式,提出基于连续弹性基础梁模型的扣件动刚度测试方法,对某服役状态下的高铁线路轨道扣件动刚度进行测试。结果表明:扣件动刚度由钢轨1阶弯曲振动的频率和参振长度、钢轨的单位长度质量和抗弯刚度以及扣件的支承间距决定,当轨道结构确定时扣件动刚度可通过测试钢轨1阶弯曲振动频率求得,其计算式在振动频率小于450 Hz时计算结果的误差小于10%;某高铁线路CRTSⅡ型板式无砟轨道服役状态下的扣件动刚度为36.5kN·mm^(-1),约为垫板静刚度的1.62倍。

关键词：高铁轨道结构钢轨连续弹性基础梁模型扣件动刚度弯曲振动测试方法

Effect of Sm doping into CuInTe_(2) on cohesive energy before and after light absorption

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Chinese Physics B 2021年第4期30卷 198-205页

作者：王泰郭永权王聪 School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China

The effects of Sm doping into CuInTe_(2) chalcopyrite on the cohesive energy before and after light absorption are systematically investigated by the empirical electron theory(EET) of solids and molecules.The results show that the static energy of CuIn_(1-x)Sm_(x)Te_(2) decreases with Sm content increasing due to the valence electronic structure modulated by doping Sm into CuIn_(1-x)Sm_(x)Te_(2).The calculated optical absorption transition energy from the static state to the excited energy level in CuIn_(1-x)Sm_(x)Te_(2) accords well with the experimental absorption bandgap of CuIn_(1-x)Sm_(x)Te_(2).Moreover,it is found that the energy bandgap of CuIn_(1-x)Sm_(x)Te_(2) is significantly widened with Sm content increasing due to its special valent electron structure,which is favorable for enhancing the light absorption in a wider range and also for the potential applications in solar cells.

关键词： CuIn_(1-x)Sm_(x)Te_(2) empirical electron theory(EET) light absorption bandgap hybridization energy