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无电荷层InGaAs/Si雪崩光电探测器的优化设计

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光学学报 2024年第5期44卷 19-28页

作者：张娟姚儿柯少颖闽南师范大学物理与信息工程学院光场调控及其系统集成应用福建省高校重点实验室福建漳州363000

目前,在近红外波段中普遍采用InGaAs/InP雪崩光电二极管(APD),但这类APD存在增益带宽积小和等效噪声高等问题,而InGaAs/Si APD采用电子、空穴离化系数极低的Si材料作为倍增层,在一定程度解决了上述问题,但其制造过程涉及Si电荷层的离子... 详细信息

目前,在近红外波段中普遍采用InGaAs/InP雪崩光电二极管(APD),但这类APD存在增益带宽积小和等效噪声高等问题,而InGaAs/Si APD采用电子、空穴离化系数极低的Si材料作为倍增层,在一定程度解决了上述问题,但其制造过程涉及Si电荷层的离子注入和高温退火激活,该过程工艺复杂、杂质分布不均匀、成本高。因此,本研究采用刻蚀技术在Si倍增层内制备凹槽环,并在凹槽环内填充不同介质对InGaAs层及Si层内的电场进行调控,构建无电荷层InGaAs/Si APD器件模型。结果表明,在凹槽环内填充空气或SiO2可获得高性能的InGaAs/Si APD。该研究结果可为后续研制工艺简单、性能稳定、低噪声的InGaAs/Si APD提供理论指导。

关键词：探测器雪崩光电二极管增益带宽积电荷层凹槽环

Characteristic and optimization of ferrite-rich sulfoaluminate-based composite cement suitable for cold region tunnels

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Journal of Central South University 2024年第8期31卷 2794-2809页

作者： Peng, You Li, Li Tan, Xian-jun Qiu, Xin Zheng, Pei-chao Xie, Jun Chen, Wei-zhong Reziwanguli, Sha-ta-er School of Infrastructure engineering Dalian University of Technology Dalian China Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China Xinjiang Academy of Transportation Sciences Co. Ltd. Urumqi China

To develop suitable grouting materials for water conveyance tunnels in cold regions, firstly, this study investigated the performance evolution of ferrite-rich sulfoaluminate-based composite cement (FSAC grouting material) at 20 and 3 °C. The results show that low temperature only delays the strength development of FSAC grouting material within the first 3 d. Then, the effect of four typical early strength synergists on the early properties of FSAC grouting material was evaluated to optimize the early (≤1 d) strength at 3 °C. The most effective synergist, Ca(hCOO)2, which enhances the low-temperature early strength without compromising fluidity was selected based on strength and fluidity tests. Its micro-mechanism was analyzed by XRD, TG, and SeM methods. The results reveal that the most suitable dosage range is 0.3 wt%–0.5 wt%. Proper addition of Ca(hCOO)2 changed the crystal morphology of the hydration products, decreased the pore size and formed more compact hydration products by interlocking and overlapping. however, excessive addition of Ca(hCOO)2 inhibited the hydration reaction, resulting in a simple and loose structure of the hydration products. The research results have reference value for controlling surrounding rock deformation and preventing water and mud inrushes during the excavation in cold region tunnels.

关键词： ferrite-rich sulfoaluminate cement cold zone early strength synergist mechanical property micro-structure pumped storage power

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTLU İsmail e.KILIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

企业eSG与资本市场表现——来自股票流动性的证据

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科学决策 2024年第4期 42-60页

作者：徐晟哈斯木其尔梁富友沈熙峰中南财经政法大学中国医药健康产业股份有限公司

在经济社会发展绿色化、低碳化态势下,eSG理念在资本市场中的地位日益凸显。文章基于2015—2021年我国A股上市公司数据,研究eSG表现对企业股票流动性的影响。研究发现,eSG表现显著提升了企业股票流动性,该效应在国有企业、大规模企业以... 详细信息

在经济社会发展绿色化、低碳化态势下,eSG理念在资本市场中的地位日益凸显。文章基于2015—2021年我国A股上市公司数据,研究eSG表现对企业股票流动性的影响。研究发现,eSG表现显著提升了企业股票流动性,该效应在国有企业、大规模企业以及市场化程度较高的地区企业中更显著。机制分析表明,企业eSG有利于提升投资者情绪和信息透明度,进而促进股票流动性。进一步研究发现,企业良好eSG表现所带来的股票流动性显著提升了企业价值和企业创新。发掘企业eSG在金融市场的作用效果,为活跃资本市场提供新的经验证据。

关键词： eSG 股票流动性投资者情绪信息透明度文本分析

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Convexification of hybrid AC-DC Optimal Power Flow with Line-Commutated Converters

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CSee Journal of Power and energy Systems 2024年第2期10卷 617-628页

作者： hongyuan Liang Zhigang Li J.h.Zheng Q.h.Wu School of electric Power engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based high-voltage DC (hVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

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乾隆朝清厘僧道停颁牒照档案(下)

历史档案 2024年第3期 4-18页

作者：哈恩忠中国第一历史档案馆

广西巡抚臣杨锡绂谨奏,为奏明事。乾隆八年四月十二日准兵部加封递到大学士鄂等字寄内开,乾隆八年三月初七日奉上谕:二氏之教由来已久,其遵守戒律闭户焚修者固于民无害,即寻常僧道,或因无力营生,藉此以免饥寒,亦难尽行沙汰。但游手之徒... 详细信息

广西巡抚臣杨锡绂谨奏,为奏明事。乾隆八年四月十二日准兵部加封递到大学士鄂等字寄内开,乾隆八年三月初七日奉上谕:二氏之教由来已久,其遵守戒律闭户焚修者固于民无害,即寻常僧道,或因无力营生,藉此以免饥寒,亦难尽行沙汰。但游手之徒借名出家,耗民财而妨民俗,自不可听其引而日盛不为清厘。

关键词：广西巡抚乾隆朝僧道八年民俗杨锡绂

痴心不悔的人文主义者语言与艺术中的表现问题

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新美术 2024年第4期45卷 4-17页

作者： e.h.贡布里希李本正天津美术学院

我的题目改自杰出钢琴家杰拉尔德·穆尔[Gerald Moore]的一本书的书名，你们也许知道，他是世界上一些伟大歌唱家，诸如菲希尔·迪斯考[Fischer Dieskau]等人的伴奏者。穆尔撰写了一部脍炙人口的回忆录，名为《问心无愧的伴奏者》[The U... 详细信息

我的题目改自杰出钢琴家杰拉尔德·穆尔[Gerald Moore]的一本书的书名，你们也许知道，他是世界上一些伟大歌唱家，诸如菲希尔·迪斯考[Fischer Dieskau]等人的伴奏者。穆尔撰写了一部脍炙人口的回忆录，名为《问心无愧的伴奏者》[The Unashamed Accompanist]，他希望表明，与一些同行不同，他并不为自己在生活中扮演的角色感到难堪，他并不想当一名独奏者或者著名的音乐会钢琴家，也不以为歌唱家伴奏而感到羞愧。恐怕我作为一名人文主义者，还不如杰拉尔德·穆尔作为伴奏者一样出色，但是尽管我常常希望自己能更出色些，我却并不希望换一份别的工作。

关键词：伴奏者人文主义者穆尔杰拉尔德歌唱家钢琴家

Shell-model representations of the microscopic version of the Bohr-Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 79-90页

作者： h G Ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

The structure of the irreducible collective spaces of the group Sp(12,R),which many-particle nuclear states are classified according to the chain Sp(12,R)⊃U(6)⊃SO(6)⊃SU_(pn)(3)⊗SO(2)⊃SO(3)of the proton-neutron symplectic model(PNSM),is considered in *** chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr-Mottelson collective *** construction of the relevant shell-model representations of the Sp(12,R)group along this chain is considered for three nuclei with varying collective properties and from different mass *** is shown that the SU_(pn)(3)basis states of the Sp(12,R)representations belonging to the SO(6)irreps with seniorityυ≥υ0,withυ0 denoting the maximal seniority SO(6)irrep contained in the Sp(12,R)bandhead,are always Pauli allowed,but organized in a different way into different SO(6)*** is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm *** the SU_(pn)(3)multiplets withinυe not all Pauli forbidden,it is safe to discard *** results obtained in the present work are important for the practical application of the microscopic version of the Bohr-Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model Sp(12,R)dynamical algebra shell-model representations

Influence of Lightning Disaster on Cities and Lightning Defense Measures

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Meteorological and environmental Research 2024年第3期15卷 65-67页

作者： Pei WANG Tao ZhaNG Tengge'er WU Xiangjun ZhaNG Ulanqab Meteorological Bureau Ulanqab 012000China huade Meteorological Bureau Ulanqab 013350China Xilinhot Meteorological Bureau Xilinhot 026000China

Under the influence of special terrain and climatic conditions,lightning weather in Ulanqab City is more frequent from June to August,and lightning disaster has become one of the important tasks of disaster prevention and *** this paper,based on the characteristics of lightning weather in Ulanqab City,the impact of lightning disaster on the city was analyzed,and lightning protection measures,such as strengthening supervision of lightning protection safety,establishing a long-term lightning protection mechanism,doing a good job in lightning protection construction and detection in key places,and further improving public awareness of lightning protection,were put forward to reduce and avoid urban lightning disasters as much as possible and ensure urban safety.

关键词： Lightning characteristics Disaster impact City Lightning protection measures