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Study on the Propagation and Focusing Mechanism of Long Waves over A Submerged Atoll

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China Ocean Engineering 2023年第2期37卷 204-217页

作者： FU Dan-juan liu Bi-jin ZHENG jin-hai WANG Gang CHEN Bi-qin School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen 361024China Hainan Institute Zhejiang UniversitySanya 572025China Key Laboratory of Coastal Disaster and Protection Ministry of EducationHohai UniversityNanjing 210098China Fujian Polytechnic of Information Technology Fuzhou 350003China

An analytical solution for long waves propagating over a submerged atoll is established. The atolls involved in this study are annular coral reefs with large lagoons in the middle, and the expression of the cross section is a trinomial function of the radial distance, i.e., h=ar(2s)-br~s+h_0, where s is the positive rational number. This analytical solution extends the theory by Wang et al.(2018) as s is no longer limited to s=2/m, where m is the positive integer. In addition, by adjusting the terrain parameters properly, the analytic solution can be degenerated to describe the wave propagation over topography with a hump or pit. According to the relationship between wave rays and wave energy, the distribution characteristics and formation mechanism of energy over the topography are expounded. When the lagoon is non-existent, all wave rays converge at the x-axis, which results in an abrupt amplification of the wave amplitude around the convergence point. When a lagoon is mounted on the top of the atoll, the rays are scattered due to the refraction of the lagoon, and only some rays converge at the symmetrical axis and the ridges on both sides,which results in the amplification of wave amplitudes in these areas.

关键词： long waves analytic solution wave scattering submerged atoll wave propagation

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai jingwei Hu Shumei Jia Chichuan jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang liu Mingjun liu Xing liu Yuan liu Zhu liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan liu Heyang liu Huaqiu liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Sciences University of Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Institute of Space Sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space Sciences University of Science and Technology of China Institute of Deep Space Sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

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嵌入式系统的需求描述综述

软件学报 2025年第1期36卷 27-46页

作者：陈小红刘少彬金芝上海市高可信计算重点实验室(华东师范大学) 高可信软件技术教育部重点实验室(北京大学) 北京大学计算机学院

随着嵌入式系统的广泛应用,其需求正变得越来越复杂,需求分析成为嵌入式系统开发的关键阶段,如何准确地建模和描述需求成为首要问题.系统地调研嵌入式系统的需求描述,并进行全面的比较分析,以便更深入地理解嵌入式系统需求的核心关注点... 详细信息

随着嵌入式系统的广泛应用,其需求正变得越来越复杂,需求分析成为嵌入式系统开发的关键阶段,如何准确地建模和描述需求成为首要问题.系统地调研嵌入式系统的需求描述,并进行全面的比较分析,以便更深入地理解嵌入式系统需求的核心关注点.首先采用系统化文献综述方法,对1979年1月–2023年11月间发表的相关文献进行识别、筛选、汇总和分析.通过自动检索和滚雪球等检索过程,筛选出150篇与主题密切相关的文献,力求文献综述的全面性.其次,从需求描述关注点、需求描述维度、需求分析要素等方面,分析现有嵌入式需求描述语言的表达能力.最后,总结现有嵌入式系统软件需求描述所面临的挑战,并针对嵌入式软件智能合成任务,提出对嵌入式系统需求描述方法表达能力的要求.

关键词：嵌入式系统需求描述需求描述语言需求分析系统需求

Comparative characterization of two natural humic acids in the Pearl River Basin, China and their environmental implications

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Journal of Environmental Sciences 2010年第11期22卷 1695-1702页

作者： juan liu jin Wang Yongheng Chen Holger Lippold Johanna Lippmann-Pipke Key Laboratory of Water Safety and Protection in the Pearl River Delta Ministry of Education Guangzhou University Guangzhou 510006 China. Forschungzentrum Dresden Rossendorf Institute of Radiochemistry Research Site Leipzig Leipzig 04318 Germany

Two humic acids （HAs） were isolated from contaminated river sediments present under comparative conditions in the Pearl River Basin, China. YFHA （the HA extracted at an open pyrite mining area in Yunfu） exhibited a lower absorption intensity for certain bands in the Fourier transform infrared spectra, a lower E 4 /E 6 value （the UV absorbances at 465 nm （E 4 ） and 665 nm （E 6 ））, a lower apparent molecular weight, a lower polarity and a lower oxygen functionality in comparison with GZHA （the HA isolated at an urban living area in Guangzhou）. All these differences indicated a higher degree of humification of YFHA than GZHA. Overall, the enrichment patterns of permanent heavy metals in the studied HAs were similar to those in corresponding sediments. In particular, YFHA exhibited high enrichment of trace element Tl, a characteristic concomitant from the mining of the pyrite minerals. The adsorption isotherms of two HAs for goethite and pyrolusite, two representative geological materials, conformed to the Langmuir equation. Based on the qualitative relationships between the Langmuir constants of the adsorption isotherms and the chemical characteristics of HAs, the main mechanism of HA adsorption on these materials was suggested to be hydrophobic interaction. This study highlighted the promising use of HA as a peculiar bio-indicator of uncommon trace metal contaminations. The HA adsorption mechanism on representative geological materials further provided a theoretical basis for the study on the unusual metal behavior in complex environmental settings.

关键词： humic acid permanent metal load adsorption goethite pyrolusite

沉积温度对氮化铝压电薄膜性能影响及机制分析

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光电子·激光 2025年第1期36卷 107-112页

作者：郭燕刘小军王进南京理工大学泰州科技学院天津三安光电有限公司

高频光电通信器件对压电材料特性要求越来越高，氮化铝（AlN）薄膜由于其优异的压电特性而备受关注，高取向高压电AlN薄膜沉积工艺优化成为其应用拓展的瓶颈技术之一，众多制备工艺参数中温度是影响AlN薄膜晶格取向的关键参数之一。本... 详细信息

高频光电通信器件对压电材料特性要求越来越高，氮化铝（AlN）薄膜由于其优异的压电特性而备受关注，高取向高压电AlN薄膜沉积工艺优化成为其应用拓展的瓶颈技术之一，众多制备工艺参数中温度是影响AlN薄膜晶格取向的关键参数之一。本文采用磁控溅射的方法沉积AlN薄膜，研究了沉积温度对AlN薄膜晶体取向及压电性能的影响，X射线衍射（X-ray diffraction, XRD）测试结果表明，250℃下可获得（100）取向AlN,300℃下AlN则优先（002）取向；压电测试结果表明，250℃下压电常数d*33达最大值0.79 V,表现出较优的压电特性。基于原子力显微镜（atomic force microscopy, AFM）结果及温度对价键稳定性影响分析探索了温度对其生长的影响机制。

关键词：氮化铝(AlN) 衬底温度取向生长压电特性

CFRP布加固无腹筋混凝土梁的抗剪作用试验研究

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土木与环境工程学报（中英文） 2025年第1期47卷 118-129页

作者：金浏蒋轩昂杜修力北京工业大学城市与工程安全减灾教育部重点实验室北京100124

对12根几何相似的CFRP加固无腹筋钢筋混凝土简支梁进行剪切破坏试验,分析梁深、配纤率对梁剪切破坏模式与失效机制的影响,获得了CFRP条带的全过程应变分布情况,讨论梁深和CFRP配纤率对CFRP条带抗剪贡献的定量影响,进而提出CFRP抗剪贡献... 详细信息

对12根几何相似的CFRP加固无腹筋钢筋混凝土简支梁进行剪切破坏试验,分析梁深、配纤率对梁剪切破坏模式与失效机制的影响,获得了CFRP条带的全过程应变分布情况,讨论梁深和CFRP配纤率对CFRP条带抗剪贡献的定量影响,进而提出CFRP抗剪贡献的计算公式,并与试验结果及规范计算结果等进行对比分析。结果表明,梁深对CFRP布抗剪贡献影响明显,即梁深增大时,CFRP布名义抗剪强度显著降低。梁高由300 mm变化至1200 mm时,CFRP名义抗剪强度下降约50%,具有明显的尺寸效应;不同尺寸下,CFRP布名义抗剪强度均随着配纤率的增大而增大,但名义抗剪强度增大幅度随着配纤率的增大而减小,呈现出非线性增长趋势;建立的CFRP抗剪承载力计算公式能较准确地预测不同配纤率及截面尺寸下的CFRP抗剪承载能力。

关键词：混凝土梁配纤率梁深剪切破坏抗剪贡献试验研究

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Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia Li Wenwu liu Shiji Da Lingbin Kong Fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

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SnO高压结构稳定性和电学性能研究

光谱学与光谱分析 2025年第1期45卷 82-87页

作者：刘涛黄宇轩高金金王世霞上海理工大学材料与化学学院上海200093

近年来氧化亚锡(SnO)在光、电等方面的应用日益广泛,为了拓宽SnO的应用范围,采用拉曼光谱原位测试和第一性原理计算对高压条件下SnO的结构性能和电子性质进行研究。SnO表征结果:扫描电子显微镜结果显示,所选取SnO样品为具有横向尺寸的... 详细信息

近年来氧化亚锡(SnO)在光、电等方面的应用日益广泛,为了拓宽SnO的应用范围,采用拉曼光谱原位测试和第一性原理计算对高压条件下SnO的结构性能和电子性质进行研究。SnO表征结果:扫描电子显微镜结果显示,所选取SnO样品为具有横向尺寸的片状堆叠,整体呈花状;X射线衍射图谱表明,SnO样品在常温常压下晶体结构为四方晶系结构(空间群P4/nmm)。采用Mao-Bell型金刚石压腔结合原位拉曼光谱探究了SnO样品在高压下的结构性能变化,结果显示:SnO在常压有四种拉曼振动模式(A_(1g)、B_(1g)、E_(1g)和E_(2g)),分别位于211、350、113和460 cm^(-1)波数附近,其中113和211 cm^(-1)为SnO拉曼特征峰。随SnO样品体系加压至12.5 GPa,压力使Sn分子间和原子间距不断减小,导致Sn-O键长缩短,当原子发生伸缩振动时,缩短的键长使得键能增大,因此活性拉曼振动模(E_(1g)和A_(1g))均向高频方向移动;随着体系压力的继续增大,晶格发生畸变进而使得非弹性散射强度降低,峰型宽化;当加压至8 GPa时,125和216 cm^(-1)附近振动模峰急剧减小;加压至10 GPa时两个特征峰完全消失,在非静水压环境下8~10 GPa时该物质发生了非晶化;当体系加压至12.5 GPa时,谱图中仍未出现新峰,表明高压下非晶化状态稳定。随后体系进行卸压,卸压至3 GPa后SnO的E_(1g)和A_(1g)模重新出现表明样品恢复低压下的晶体结构,卸至常压特征峰强度明显分别为110和209 cm^(-1)处与加压前吻合,证明了SnO高压相变行为具有可逆性。为进一步了解压力对SnO电学性能影响,使用第一性原理方法计算了SnO在常压和实验非晶化压力(8 GPa)下的电子性质,通过非晶化前后SnO的带隙宽度变化,探究压力对SnO导电性能的影响。结果显示,在常压下SnO为具有0.43 eV带隙的间接带隙半导体,在费米能级附近态密度没有发生重叠,8 GPa时SnO显示金属性质,由于SnO O-p、Sn-s和Sn-p轨道的态密度在费米能级处重叠,导致带隙的闭合,材料发生金属化。研究结果表明SnO高压下可能产生非晶化及压力所导致的非晶化行为可逆,同时高压导致SnO发生半导体到金属的转变,拓展了SnO高压结构和电学性质的探究,为SnO高压下的应用提供进一步帮助。

关键词： SnO 拉曼光谱金刚石压腔第一性原理电子性质

Effects of Vitamin E on the Activities of Protective Enzymes and Membrane Lipid Peroxidation in Leymus Chinensis under Drought Stress

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Chemical Research in Chinese Universities 2008年第1期24卷 80-83页

作者： GU Jie liu Gong-she GUO juan ZHANG jin Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education Jilin University Changchun 130021 P. R. China Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 P. R. China

Leymus chinensis seedlings were treated with 0.05--10 mmol/L vitamin E under osmotic stress in the presence of polyethylene glycol（PEG） as the stress reagent. The effects of the different concentrations of exogenous vitamin E on the activities of SOD, POD and free proline, and the MDA contents under drought stress were examined so as to ascertain the mechanism of Leymus chinensis resistance to drought stress and explore the possible preventive measures. The results indicate that the activities of SOD and POD decreased but the free proline and MDA contents increased as drought stress was accentuated, showing an enhancement of oxidative stress that may cause a decline in membrane stabilization. However, the activities of SOD and POD and the free proline content increased, whereas the MDA content reduced in Leymus chinensis pretreated with vitamin E in comparison with that of the control. This indicates that exogenous vitamin E enhanced the antioxidation of Leymus chinensis seedlings. It suggests that cytomembrane can be protected from damage by increasing the free proline content and the activities of SOD and POD that result in enhancing the drought resistance of Leymus chinensis seedlings.

关键词： Vitamin E Drought stress Leymus chinensis Protective enzyme Membrane lipid peroxidation