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Electric Anisotropy and Two－dimensional Energy Band of Undoped and Heavily Doped Polyacetylene

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Chemical Research in Chinese Universities 1995年第3期11卷 228-231页

作者： Huang, Zong-hao Wang, Xiu-jun Tong, La-ga li, bai-tao Wang, Rong-shun Bei, Yong-ping

ased on the known crystal data , we used the EHMACC(EHMO/CO) methodto calculate the twotlimensional energy band of both undoped and heavily iodine-doped polyacetylene (PA). The results show that (1 ) I-doping obviously reducesthe niagnitudes of Eg , Egi; (2) in the conducting process along the direction per-pendicular to PA chain , the P-type AO of iodine plays a very important role, i- e. ,the conducting bridge to transport the charge between the two neighbor PA chains.I-doping reniarkably increases σ_T value while the conducting process will reduce theratio magnitude of σ/σ. Therefore, heavily I-doping makes PA change fromsimeconductor to conductor which obviously has 2-D conductive ability.

关键词： Conductive polymer 2-D energy band Electric anisotropy

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含轴电流损伤的球轴承动力学建模及特性分析

东北大学学报（自然科学版） 2023年第10期44卷 1431-1439页

作者：李小彭曲兴超李柏涛苏晶东北大学机械工程与自动化学院辽宁沈阳110819

以风力发电机球轴承为研究对象,提出了凹坑形式的轴电流损伤模型,分析该损伤对轴承动力学特性的影响规律.利用半正弦和分段激励函数建立了一个含长度、宽度和深度的损伤模型,用于描述轴电流的不同损伤程度;建立了含轴电流损伤的轴承动... 详细信息

以风力发电机球轴承为研究对象,提出了凹坑形式的轴电流损伤模型,分析该损伤对轴承动力学特性的影响规律.利用半正弦和分段激励函数建立了一个含长度、宽度和深度的损伤模型,用于描述轴电流的不同损伤程度;建立了含轴电流损伤的轴承动力学模型,来研究损伤凹坑的大小和形状及外载荷对轴承的振动特性影响;通过轴承的接触分析,研究了轴电流损伤程度对轴承载荷分布的影响;将仿真结果和实验对比,验证了模型的正确性.研究结果表明:所提出的模型可以准确地描述由凹坑形式的轴电流损伤导致的冲击激励与周期性变化现象;随着轴电流损伤程度的增大,轴承的振动响应和接触力变大,系统趋于不稳定.

关键词：轴电流损伤模型轴承载荷动力学

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基于PLC的循环气压缩机安全联锁设计

仪表技术与传感器 2016年第12期 69-72,82页

作者：李鸣白焘南昌大学信息工程学院江西南昌330031 南昌大学机电工程学院江西南昌330031

以环氧乙烷生产工艺中循环气压缩机为例,介绍了循环气压缩机在反应单元中的联锁控制。为确保压缩机安全稳定地运行,设计了一套基于PLC的双重化冗余压缩机紧急停车系统。同时利用软件PLCSIM对系统进行了仿真模拟,通过Win CC软件设计了人... 详细信息

以环氧乙烷生产工艺中循环气压缩机为例,介绍了循环气压缩机在反应单元中的联锁控制。为确保压缩机安全稳定地运行,设计了一套基于PLC的双重化冗余压缩机紧急停车系统。同时利用软件PLCSIM对系统进行了仿真模拟,通过Win CC软件设计了人机界面,实现了工艺参数的实时监测。此外系统采用的数据通过多原则表决与修正,避免了由于信号误差带来的经济损失,为工业安全起到一定的保障作用。

关键词：循环压缩机联锁逻辑软件仿真监控界面表决与修正

Effect of lamellarization on the microstructure and mechanical properties of marine 10Ni5CrMoV steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 402-413页

作者： tao Zou Yanwu Dong Zhouhua Jiang Shuyang Du Yushuo li School of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Key Laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education) Northeastern UniversityShenyang 110819China

Multistage heat treatment involving quenching(Q),lamellarizing(L),and tempering(T)is applied to marine 10Ni5CrMoV *** microstructure and mechanical properties were studied by multiscale characterizations,and the kinetics of reverse austenite transformation,strain hardening behavior,and toughening mechanism were further *** lamellarized specimens possess low yield strength but high toughness,especially cryogenic *** leads to the development of film-like reversed austenite at the martensite block and lath boundaries,refining the martensite structure and lowering the equivalent grain *** analysis of austenite reversion based on the JMAK model shows that the isothermal transformation is dominated by the growth of reversed austenite,and the maximum transformation of reversed austenite is reached at the peak temperature(750℃).The strain hardening behavior based on the modified Crussard-Jaoul analysis indicates that the reversed austenite obtained from lamellarization reduces the proportion of martensite,significantly hindering crack propagation via martensitic transformation during the *** a consequence,the QLT specimens exhibit high machinability and low yield *** with the QT specimen,the ductile-brittle transition temperature of the QLT specimens decreases from-116 to-130℃due to the low equivalent grain size and reversed austenite,which increases the cleavage force required for crack propagation and absorbs the energy of external load,*** work provides an idea to improve the cryogenic toughness of marine 10Ni5CrMoV steel and lays a theoretical foundation for its industrial application and comprehensive performance improvement.

关键词： 10Ni5CrMoV steel lamellarizing reversed austenite cryogenic toughness ductile-brittle transition temperature

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： lin Peng Yu bai Hang li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

lithium-sulfur （li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （liPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes li2S dissolution and nucleation ***,the li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： lithium sulfur batteries

超声萃取-C_(18)柱净化-GC/MS法测定土壤中邻苯二甲酸酯类污染物

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光谱实验室 2010年第5期27卷 1705-1709页

作者：白利涛张占恩苏州科技学院江苏省环境科学与工程重点实验室

采用超声波辅助萃取-非极性C18固相萃取小柱净化-GC/MS技术,测定了土壤样品中6种邻苯二甲酸酯类污染物;对最佳溶剂萃取条件和最佳净化条件进行了优化;在最佳实验条件下,方法的相对标准偏差在6.5%—10.6%之间,最低检出限在0.005—0.049mg... 详细信息

采用超声波辅助萃取-非极性C18固相萃取小柱净化-GC/MS技术,测定了土壤样品中6种邻苯二甲酸酯类污染物;对最佳溶剂萃取条件和最佳净化条件进行了优化;在最佳实验条件下,方法的相对标准偏差在6.5%—10.6%之间,最低检出限在0.005—0.049mg/kg之间,实际土样加标回收率在73.9%—105.4%之间。

关键词：超声辅助萃取 C18固相萃取柱净化土壤邻苯二甲酸酯

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin bai Xiaodong li Peng Ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)