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基于光捕获效应的Ti3C2Tx/硅纳米线异质结光电探测器

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科学技术创新 2025年第1期 17-20页

作者：喻杰合肥工业大学安徽合肥

通过金属辅助化学刻蚀法制备了硅纳米线(Si NWs),使用最小强化层脱层刻蚀技术分离了Ti_(3)C_(2)Tx纳米片,随后构筑了Ti_(3)C_(2)Tx/Si NWs异质结光电探测器。利用扫描电子显微镜对Ti_(3)C_(2)Tx/Si NWs的形貌进行分析,采用X射线衍射仪... 详细信息

通过金属辅助化学刻蚀法制备了硅纳米线(Si NWs),使用最小强化层脱层刻蚀技术分离了Ti_(3)C_(2)Tx纳米片,随后构筑了Ti_(3)C_(2)Tx/Si NWs异质结光电探测器。利用扫描电子显微镜对Ti_(3)C_(2)Tx/Si NWs的形貌进行分析,采用X射线衍射仪分析了Ti_(3)C_(2)Tx的结构。器件分析表明,该器件呈现出宽带响应特性,在920 nm处具有约526 mA/W的峰值响应度,其响应相较于平面硅器件有了很大的提升。这种光电特性与Si NWs中的光捕获效应有关。这些结果表明,Si NWs是未来高性能硅基光电探测器的潜在构建模块。

关键词：硅纳米线光电探测器光捕获效应

A time integral formulation and algorithm for structural dynamics with nonlinear stiffness

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Acta Mechanica Sinica 2006年第5期22卷 479-485页

作者： Kaiping yu jie Zhao Department of Astronautical Science and Mechanics Harbin Institute of Technology Harbin 150001 China

A newly-developed numerical algorithm, which is called the new Generalized-α （G-α） method, is presented for solving structural dynamics problems with nonlinear stiffness. The traditional G-α method has undesired overshoot properties as for a class of α-method. In the present work, seven independent parameters are introduced into the single-step three-stage algorithmic formulations and the nonlinear internal force at every time interval is approximated by means of the generalized trapezoidal rule, and then the algorithm is implemented based on the finite difference theory. An analysis on the stability, accuracy, energy and overshoot properties of the proposed scheme is performed in the nonlinear regime. The values or the ranges of values of the seven independent parameters are determined in the analysis process. The computational results obtained by the new algorithm show that the displacement accuracy is of order two, and the acceleration can also be improved to a second order accuracy by a suitable choice of parameters. Obviously, the present algorithm is zero- stable, and the energy conservation or energy decay can be realized in the high-frequency range, which can be regarded as stable in an energy sense. The algorithmic overshoot can be completely avoided by using the new algorithm without any constraints with respect to the damping force and initial conditions.

关键词： Nonlinear structural dynamics Numerical algorithm Stability Overshoot

单层Cs_(2)PbI_(2)Cl_(2)中点缺陷的形成与稳定性

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原子与分子物理学报 2025年第5期42卷 130-136页

作者：何诗颖赵宇清邹代峰许英廖雨洁禹卓良湖南科技大学物理与电子科学学院湘潭411201 智能传感器与新型传感器材料湖南省重点实验室湘潭411201 湖南理工学院物理与电子科学学院岳阳414006

Cs_(2)PbI_(2)Cl_(2)是卤化铅钙钛矿材料的新成员,由于其高的光吸收系数和长的载流子迁移距离等优异的光电物理性能,在太阳能电池、光电探测器、场效应晶体管以及发光二极管等领域受到广泛的关注.其中光电材料及器件的优良特性由电子结... 详细信息

Cs_(2)PbI_(2)Cl_(2)是卤化铅钙钛矿材料的新成员,由于其高的光吸收系数和长的载流子迁移距离等优异的光电物理性能,在太阳能电池、光电探测器、场效应晶体管以及发光二极管等领域受到广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而钙钛矿的点缺陷对电子结构具有重要的调控,且单层Cs_(2)PbI_(2)Cl_(2)中点缺陷的研究尚且缺乏.本文基于密度泛函理论的第一性原理计算,对单层Cs_(2)PbI_(2)Cl_(2)的铯空位、碘空位、氯空位、铯替代铅、碘替代铯、碘替代铅、碘替代氯、氯替代铯、氯替代铅和氯替代碘的缺陷形成能和稳定性进行了研究.结果表明:在富铅和缺铅条件下,碘替代氯和氯替代碘的缺陷形成能偏低,且氯替代碘能有效降低体系总能,提高体系稳定性.在缺铅条件下铯空位缺陷形成能低于富铅条件,在缺铅条件下更易形成铯空位;富铅和缺铅条件下对碘替代氯和氯替代碘的缺陷形成能基本无影响.上述研究结果有助于理解点缺陷对钙钛矿材料稳定性的影响,同时也为未来实验上设计基于Cs_(2)PbI_(2)Cl_(2)的高效的光电子器件提供理论依据.

关键词：单层Cs_(2)PbI_(2)Cl_(2) 形成能点缺陷稳定性

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体相二硫化铼中点缺陷的形成与稳定性

原子与分子物理学报 2025年第5期42卷 143-150页

二硫化铼是过渡金属二硫族化合物的成员,由于层间的范德华作用、合适的带隙、高的光吸收系数和长的载流子迁移距离在光电子研究领域引起广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而半导体的缺陷能级对电子结构具有重要... 详细信息

二硫化铼是过渡金属二硫族化合物的成员,由于层间的范德华作用、合适的带隙、高的光吸收系数和长的载流子迁移距离在光电子研究领域引起广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而半导体的缺陷能级对电子结构具有重要的调控,且体相二硫化铼的缺陷研究尚且缺乏.本文基于密度泛函理论的第一性原理计算,对体相二硫化铼的铼空位、硫空位、钨掺杂(或替代)铼、钨掺杂硫、锝掺杂铼和锝掺杂硫的缺陷形成能和稳定性进行了研究.结果表明:钨掺杂硫和锝掺杂硫形成深施主能级缺陷,铼空位形成浅施主能级缺陷.在富铼和富硫条件下,钨掺杂铼的缺陷形成能低且能有效降低体系总能,提高体系稳定性.钨掺杂硫的缺陷虽然能降低体系的总能提高二硫化铼的稳定性,但较大的缺陷形成能表明钨掺杂硫缺陷难以形成.上述研究结果有助于理解缺陷能级对半导体深浅能级和稳定性的影响,同时也为未来实验上设计基于二硫化铼的高效的光电子器件提供理论依据.

关键词：体相二硫化铼形成能缺陷能级稳定性

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One-dimensional(1D) micro/nanostructures of organic semiconductors for field-effect transistors

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Science China Chemistry 2015年第6期58卷 937-946页

作者： yu-Qing Zheng jie-yu Wang Jian Pei Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University

Organic semiconductors have gradually become the super stars on the stage of optoelectronic materials, due to their low cost, flexibility and solution processability. Numerous organic semiconductors, including small molecules and conjugated polymers, have been designed and synthesized to explore the potential of organic materials in optoelectronic industry. One-dimensional micro/nanostructures of organic semiconductors generally have more ordered packing structure with fewer defects compared with thin films, and are thus thought to show intrinsic carrier mobility of organic materials. Moreover, the packing structure in micro/nanostructures is clear and relatively easy to analyze, which makes these micro/nanostructures a good platform to study structure-property relationship. Therefore, design of suitable organic molecules to form micro-/nanostructures and methods to obtain ideal micro/nanostructures for functional devices will be fully discussed in this mini review. Finally, the perspective and opportunity of 1D micro/nanostructured organic materials based OFETs in the near future are also addressed.

关键词： organic semiconductors organic field-effect transistors one-dimensional micro/nanostructures self-assembly

高光谱预处理方法与多模型在分类判别中的对比研究

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光谱学与光谱分析 2025年第1期45卷 125-132页

作者：居雷于洁吴炎淼李丽卢天丁亚萍束茹欣上海烟草集团有限责任公司技术中心上海200082 上海大学化学系上海200444 上海数之微信息科技有限公司上海200444

高光谱技术能够快速、无损地获取丰富的信息,在植物研究和监测中已成为一种广泛应用的工具。茄科植物作为一种重要的经济农作物,与高光谱技术结合进行研究具有巨大的应用潜力。本研究采用高光谱技术对茄科植物的初烤后不同部位叶片进行... 详细信息

高光谱技术能够快速、无损地获取丰富的信息,在植物研究和监测中已成为一种广泛应用的工具。茄科植物作为一种重要的经济农作物,与高光谱技术结合进行研究具有巨大的应用潜力。本研究采用高光谱技术对茄科植物的初烤后不同部位叶片进行分类研究。采用Field Spec 3光谱辐射仪对293份不同部位的茄科植物粉末样本进行高光谱采样,采用S-G平滑以及一阶导数和二阶导数的方法对数据进行预处理,用于信息增强和去除噪声,并通过偏最小二乘法对数据进行降维,以减少冗余特征。基于降维数据,采样支持向量机、逻辑回归、K近邻、决策树、随机森林和梯度提升决策树这六种机器学习算法建立分类模型。结果显示,在分类任务中,经过一阶导数处理后,支持向量机模型最佳,在训练集和测试集上分别实现了100.0%和84.7%的准确率。经网格参数优化后确定最优参数为:最大深度不限制,最小样本分割数为4,估计器数量为200。参数优化后五折交叉验证准确率为88.1%,训练集准确率为100%,测试集准确率为86.4%。研究结果表明,预处理方法结合降维方法能够增强数据信息使得分类模型能够更好地捕捉茄科植物样本的特征。该研究对于快速、准确、无损地区分茄科植物的部位具有重要意义。

关键词：高光谱部位分类机器学习

Vibrations of tandem cold rolling mill: coupled excitation of rolling force and variable stiffness of fault-free back-up roll bearing

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Journal of Iron and Steel Research International 2023年第9期30卷 1792-1802页

作者： yu-jie Liu Shen Wang jie-bin Qi Xiao-qiang Yan School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Department of Mechanical Engineering and Mechanics Lehigh UniversityBethlehemCommonwealth of Pennsylvania 18015USA

Vibration issues of a five-stand tandem cold rolling mill were found in the steel production practice,and the experimental observation and numerical analysis indicated that the vibrations were related to the back-up roll *** results were validated by replacing the back-up roll bearing with the new bearing resulting in 30%decline in vibration *** describing the four-row cylindrical roller bearing and the vertical system of the cold rolling mill including the bearing were ***,the mechanisms of periodic excitation and amplified vibrations of fault-free bearing were explained theoretically,along with the analysis of bifurcation behaviors of the motion states of the roller bearing and rolling mill *** is found that the energy transmitted between vibrations with different frequencies if multiple excitation frequencies in the rolling mill system were close.

关键词： Rolling mill vibration Cold tandem mill Fault-free bearing Vibration amplification Variable stiffness Characteristics

Macroporous Directed and Interconnected Carbon Architectures Endow Amorphous Silicon Nanodots as Low‑Strain and Fast‑Charging Anode for Lithium‑Ion Batteries

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Nano-Micro Letters 2024年第5期16卷 333-351页

作者： Zhenwei Li Meisheng Han Peilun yu Junsheng Lin jie yu Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Shenzhen Engineering Lab for Supercapacitor MaterialsSchool of Material Science and EngineeringHarbin Institute of TechnologyShenzhenUniversity TownShenzhen 518055People’s Republic of China Songshan Lake Materials Laboratory Dongguan Dongguan 523808GuangdongPeople’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fabricating low-strain and fast-charging silicon-carbon composite anodes is highly desired but remains a huge challenge for lithium-ion ***,we report a unique silicon-carbon composite fabricated by uniformly dis-persing amorphous Si nanodots(SiNDs)in carbon nanospheres(SiNDs/C)that are welded on the wall of the macroporous carbon framework(MPCF)by vertical graphene(VG),labeled as MPCF@VG@SiNDs/*** high dispersity and amor-phous features of ultrasmall SiNDs(~0.7 nm),the flexible and directed electron/Li+transport channels of VG,and the MPCF impart the MPCF@VG@SiNDs/C more lithium storage sites,rapid Li+transport path,and unique low-strain property during Li+***,the MPCF@VG@SiNDs/C exhibits high cycle stability(1301.4 mAh g^(-1) at 1 A g^(-1) after 1000 cycles without apparent decay)and high rate capacity(910.3 mAh g^(-1),20 A g^(-1))in half cells based on industrial electrode *** assembled pouch full cell delivers a high energy density(1694.0 Wh L^(-1);602.8 Wh kg^(-1))and an excellent fast-charging capability(498.5 Wh kg^(-1),charging for 16.8 min at 3 C).This study opens new possibilities for preparing advanced silicon-carbon com-posite anodes for practical applications.

关键词： Amorphous Si nanodots Low-strain Fast-charging Lithium-ion batteries

非遗技艺数字化保护的发展趋势研究——基于CiteSpace科学知识图谱的可视化分析

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长江师范学院学报 2025年第1期41卷 125-132页

作者：郭延龙孙玉洁新疆和田学院艺术学院新疆和田848000 安徽大学艺术学院安徽合肥230601

研究以“非遗技艺数字化保护”英文关键词为检索对象,将Web of Science核心合集数据库作为数据源。利用CiteSpace科学知识图谱的可视化手段,对非遗技艺数字化保护发展趋势研究、关键词共现等相关主题归纳分析,揭示出非遗技艺数字化保护... 详细信息

研究以“非遗技艺数字化保护”英文关键词为检索对象,将Web of Science核心合集数据库作为数据源。利用CiteSpace科学知识图谱的可视化手段,对非遗技艺数字化保护发展趋势研究、关键词共现等相关主题归纳分析,揭示出非遗技艺数字化保护的发展现状、热点分析和未来趋势。得出数字化技术与非遗技艺的深度融合是非遗技艺数字化保护未来发展重点,同时更加重视非遗技艺数据库的完善,非遗数字化技术的继承、传播与发展和对相关技术人员的培养。

关键词：非遗保护数字化知识图谱 CiteSpace