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Efficient homojunction tin perovskite solar cells enabled by gradient germanium doping

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Efficient homojunction tin perovskite solar cells enabled by...

Irreversible Colossal Magnetoresistance in La_(0.58)Dy_(0.09)Ca_(0.33)MnO_3

第十一届新型太阳能材料科学与技术学术研讨会

作者： Zhenzhu Zhao Mulin Sun Yuyang Ji Kaitian Mao Zongming Huang chengjian yuan Yuqian Yang Honghe Ding Yingguo Yang Yu Li Wenjing Chen Junfa Zhu Jing Wei Jixian Xu Watcharaphol Paritmongkol Antonio Abate Zhengguo Xiao Lixin He Qin Hu School of Microelectronics University of Science and Technology of China

P-type self-doping is known to hamper tin-based perovskites for developing highperformance solar cells by increasing background current density and carrier recombination *** this work,we propose a gradient homojunction structure with germanium doping that generates an internal electric field across the perovskite film to deplete the charge *** structure reduces the dark current density of perovskite by over two orders of magnitude and trap density by an order of *** resultant tin-based perovskite solar cells exhibit a higher power conversion efficiency of 13.2% and excellent stability,maintaining 95% and 85% of their initial efficiencies after 250 min of continuous illumination and 3800 h of storage,*** reveal the homojunction formation mechanism using density functional theory calculations and molecular-level *** work provides a reliable strategy for controlling the spatial energy levels in tin perovskite films and offers insights for designing intriguing lead-free perovskite optoelectronics.

关键词： tin-based perovskite gradient homojunction perovskite solar cells

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Journal of Materials Science & Technology 2003年第6期19卷 622-624页

作者： Baoxin HUANG, Yihua LIU, Ruzhen ZHANG, Youyong DAI, chengjian WANG, Xiaobo yuan and Liangmo MEIDepartment of Physics and State Key Laboratory of Crystal Materials, Shandong University, Ji’nan 250100, China Lab. of Crystal Mat. Dept. of Phys. Shandong Univ. Ji'nan 250100 China

The representative sample La0.58Dy0.09Ca0.33MnO3 of Dy doped La0.67Ca0.33MnO3 rare-earth manganites was investigated. The most important effect of Dy doping is to introduce the magnetoimpurity and form the spin clusters which induce dramatically large CMR in La0.58Dy0.09Ca0.33MnO3. The fitting results of field-induced resistivity decrease to the Brillouin function indicate that the CMR is caused by the spin dependent hopping between spin clusters. It is the magnetic field that reduces the size of spin clusters and induces a field-induced irreversible CMR behaviour.

关键词： Spin cluster Magnetoimpurity Colossal magnetoresistance

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液压支架推杆前端结构改进研究

中州煤炭 2016年第1期 112-114页

作者：袁成健燕全超郑州煤矿机械集团股份有限公司河南郑州450000

综采工作面液压支架使用时经常出现推杆前端损坏现象,推移机构用来移架和推刮板输送机。如果推移机构失效,将无法实现移架和推刮板输送机,对工作面的生产影响很大。通过对推杆使用情况下的受力分析,优化推杆前端结构,加强工作面液压支... 详细信息

综采工作面液压支架使用时经常出现推杆前端损坏现象,推移机构用来移架和推刮板输送机。如果推移机构失效,将无法实现移架和推刮板输送机,对工作面的生产影响很大。通过对推杆使用情况下的受力分析,优化推杆前端结构,加强工作面液压支架的使用管理,从而避免出现推杆前端损坏现象。

关键词：综采工作面液压支架推杆受力安全系数

基于高精度径向开孔和定子高程测量的定子基础板更换方法

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水电与新能源 2022年第10期36卷 60-63页

作者：刘元峰袁成建广东能源集团新丰江发电公司检修部广东河源517000 华中科技大学土木与水利工程学院湖北武汉430074

为提升采用竖向销钉定位的水轮发电机组定子安装稳定性,提出了一套完整的定子基础板更换方案。通过合理安排工序流程及在拆装过程中准确记录关键部位尺寸,指导基础板制造,保证其径向销钉孔的轴线水平且方向准确指向机组定子圆心,克服了... 详细信息

为提升采用竖向销钉定位的水轮发电机组定子安装稳定性,提出了一套完整的定子基础板更换方案。通过合理安排工序流程及在拆装过程中准确记录关键部位尺寸,指导基础板制造,保证其径向销钉孔的轴线水平且方向准确指向机组定子圆心,克服了现场开孔精度不足、基础板与机组中心配合困难的问题。经在某电站4台问题机组上的应用和修复前后机组上机架水平振幅值的对比表明,机组运行的稳定性与安全水平得到了显著提升。

关键词：定子基础板径向销钉对中

THE PERSISTENCE OF SOLUTIONS IN A NONLOCAL PREDATOR-PREY SYSTEM WITH A SHIFTING HABITAT

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Acta Mathematica Scientia 2024年第3期44卷 1096-1114页

作者：赵敏袁荣 School of Science Tianjin Chengjian UniversityTianjin300384China Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing100875China

In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting *** is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or extinction of the prey and of the predator separately in various moving *** particular,they achieved a complete picture in the local diffusion ***,the question of the persistence of the prey and of the predator in some intermediate moving frames in the nonlocal diffusion case was left open in Choi et al.'s *** using some a prior estimates,the Arzelà-Ascoli theorem and a diagonal extraction process,we can extend and improve the main results of Choi et *** achieve a complete picture in the nonlocal diffusion case.

关键词： predator-prey system persistence nonlocal dispersal shifting environment

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泄压坑道式工房内爆试验与数值模拟研究

兵工学报 2024年第7期45卷 2404-2413页

作者：陈泰年任辉启李素灵张珊珊张程健袁野军事科学院国防工程研究院北京100850 中国兵器工业火炸药工程与安全技术研究院北京100053 北京理工大学爆炸科学与技术国家重点实验室北京100081 北京理工大学重庆创新中心重庆401135

为探索复合构型坑道式工房内爆炸效应和泄压消波措施,提出泄压坑道式工房设计。通过理论分析和线性拓展预测的方法预判坑道内压力分布,建立多工况泄压坑道式工房的有限元模型。通过数值模拟得出结构内部和外部冲击波传播与衰减的规律,... 详细信息

为探索复合构型坑道式工房内爆炸效应和泄压消波措施,提出泄压坑道式工房设计。通过理论分析和线性拓展预测的方法预判坑道内压力分布,建立多工况泄压坑道式工房的有限元模型。通过数值模拟得出结构内部和外部冲击波传播与衰减的规律,分析冲击波涡流成型机理以及泄压消波的过程,计算得到多工况下坑道内部和外部的压力分布规律。通过试验研究对线性拓展计算和数值模拟结果进行对比分析,揭示由丁字接头、泄压通道、膨胀室组成的复合构型坑道式工房对于消波效率的显著提升作用,得出坑道结构内泄压消波的效能以及坑道结构口部外冲击波分布规律,以期为坑道式工房的结构选型及布局优化设计提供技术支撑。

关键词：泄压坑道式工房泄压消波冲击波传播规律压力分布规律

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Linearized Transformed L1 Galerkin FEMs with Unconditional Convergence for Nonlinear Time Fractional Schr¨odinger Equations

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Numerical Mathematics(Theory,Methods and Applications) 2023年第2期16卷 348-369页

作者： Wanqiu yuan Dongfang Li chengjian Zhang School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China

A linearized transformed L1 Galerkin finite element method(FEM)is presented for numerically solving the multi-dimensional time fractional Schr¨odinger *** optimal error estimates of the fully-discrete scheme are *** error estimates are obtained by combining a new discrete fractional Gr¨onwall inequality,the corresponding Sobolev embedding theorems and some inverse *** the previous unconditional convergence results are usually obtained by using the temporal-spatial error spitting *** examples are presented to confirm the theoretical results.

关键词： Optimal error estimates time fractional Schr¨odinger equations transformed L1 scheme discrete fractional Gr¨onwall inequality

Theoretical analysis of the double-differential cross-sections of neutron,proton,deuteron,^(3)He,andαfor the p+^(6) Li reaction

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Nuclear Science and Techniques 2024年第3期35卷 181-197页

作者： Fang-Lei Zou Xiao-Jun Sun Jing-Shang Zhang Hai-Rui Guo Yin-Lu Han Rui-Rui Xu Xi Tao Ji-Min Wang Xiao-Dong Sun yuan Tian Tao Ye Yong-Li Xu Chun-Tian Liang College of Physics Guangxi Normal University541004 GuilinChina Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology 541004 GuilinChina China Institute of Atomic Energy P.O.Box 275(41)102413 BeijingChina Institute of Applied Physics and Computational Mathematics 10094 BeijingChina College of Physics and Electronic Shanxi Datong University037009 DatongChina School of Science Tianjin Chengjian University300384 TianjinChina

Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the *** reaction channels,including sequential and simultaneous emission processes,are analyzed in *** the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted *** optical potential parameters of the proton are obtained by fitting the elastic scattering differential *** calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing ***,the mixed double differential cross-sections of^(3) He andαare in good agreement with the *** agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction *** on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles.

关键词： Statistical theory of light nucleus reaction p+^(6)Li reaction Light composite charged particle Double-differential cross-sections Two-body breakup Three-body breakup

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炼钢过程中铁合金减量化技术研究

江西冶金 2024年第4期44卷 280-288页

作者：张笑盼华承健徐维利包燕平赵立华北京科技大学冶金与生态工程学院北京100083 太原科技大学材料科学与工程学院太原030024 建龙西林钢铁有限公司伊春153025 北京科技大学绿色低碳钢铁冶金全国重点实验室北京100083

炼钢过程铁合金减量化有助于钢铁企业节能减排,并可节约其生产成本。本研究采用转鼓实验、数据分析和钢水量校准等方法,考察了合金粉化率、合金成分、合金收得率等对合金成本的影响。结果表明,合金粉化率升高,合金元素的收得率降低;当... 详细信息

炼钢过程铁合金减量化有助于钢铁企业节能减排,并可节约其生产成本。本研究采用转鼓实验、数据分析和钢水量校准等方法,考察了合金粉化率、合金成分、合金收得率等对合金成本的影响。结果表明,合金粉化率升高,合金元素的收得率降低;当硅锰合金中Mn含量由64.7%提高至66.6%时,每吨钢的合金化成本由243.62元下降至241.89元,升高合金品位可降低合金消耗量。当钢水量偏差在-2%~0范围内时,合金化成本最低。因此,钢铁企业应定期检查钢包秤的精准度。

关键词：炼钢合金减量低成本合金收得率合金粉化率