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Pulse shaping of bright-dark vector soliton pair

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Chinese Physics B 2020年第5期29卷 235-242页

作者： Yan Zhou Yuefeng Li Xia Li Meisong Liao jingshan hou Yongzheng Fang School of Science Shanghai Institute of TechnologyShanghai 201418China Key Laboratory of Materials for High Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Materials Science and Engineering Shanghai Institute of TechnologyShanghai 201418China

We simulate pulse shaping of bright-dark vector soliton pair in an optical fiber *** changing input pulse parameters(amplitude ratio,projection angle,time delay,and phase difference),different kinds of pulse shapes and spectra can be *** input bright-dark vector soliton pair with the same central wavelength,“2+1”-and“2+2”-type pseudo-high-order bright-dark vector soliton pairs are *** for the case of different central wavelengths,bright-dark vector soliton pairs with multiple pulse peaks/dips are demonstrated with appropriate pulse parameter setting.

关键词： bright-dark vector soliton birefringence polarization-locking group-velocity-locking

CsPbBr3 nanocrystal for mode-locking Tm-doped fiber laser

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Chinese Physics B 2019年第9期28卷 193-196页

作者： Yan Zhou Renli Zhang Xia Li Peiwen Kuan Dongyu He jingshan hou Yufeng Liu Yongzheng Fang Meisong Liao School of Science Shanghai Institute of TechnologyShanghai 201418China Key Laboratory of Materials for High Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Materials Science and Engineering Shanghai Institute of TechnologyShanghai 201418China

CsPbBr3 nanocrystal is used as the saturable absorber(SA) for mode-locking Tm-doped fiber laser in a ring fiber *** modulation depth, saturable intensity, and non-saturable loss of the fabricated SA are 14.1%, 2.5 MW/cm^2,and 5.9%, *** the mode-locking operation, the mode-locked pulse train has a repetition rate of 16.6 MHz with pulse width of 24.2 *** laser wavelength is centered at 1992.9 nm with 3-dB spectrum width of 2.5 *** maximum output power is 110 mW with slope efficiency of 7.1%.Our experiment shows that CsPbBr3 nanocrystal can be used as an efficient SA in the 2-μm wavelength region.

关键词： nanocrystal saturable absorber mode-locking fiber laser

Eu^(2+) and Dy^(3+) codoped(Ca,Sr)_7(SiO_3)_6Cl_2 highly efficient yellow phosphor

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Journal of Rare Earths 2014年第9期32卷 812-816页

作者：刘冯新房永征张娜候京山张灵彦于圣洁刘淑培 School of Materials Science and Engineering Shanghai Institute of Technology School of Chemistry and Chemical Engineering Shanghai Jiao Tong University College of Materials Science and Engineering Donghua University

Eu2＋ and Dy3＋ codoped （Ca, Sr）7（SiO3）6C12 yellow phosphors were successfully synthesized by self-flux method. The structure, morphology and photoluminescence properties were investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and photoluminescence spectra. The as-prepared phosphor showed a broad emission spectrum centered at 550 nm for Eu2＋ single-doped phosphor, while located at 548 544 nm for the Eu2＋, Dy3＋ codoped samples under excitation at 380 nm light. The emission intensity was greatly improved when Dy3＋ was doped into the （Ca,Sr）7（SiO3）6C12：Eu2＋ system. The composition-optimized sample with 3 mol.% of Dy3＋ and constant 10 tool.% of Eu2＋ exhibited a 220% PL enhancement compared to the phosphor with 10 tool.% Eu2＋ single-doped. Meanwhile, it was found that the quantum efficiency of phosphor namely （Ca,Sr）7（SiO3）6Cl2：3 tool.% Dy3＋ 10 mol.% Euz＋ could get up to 24.6%. The synthesized yellow-emitting （Ca,Sr）7（SiO3）6C12：Dy3＋,Eu2＋ is a promising candidate as high-efficiency yellow phosphor for NUV-excited white LEDs.

关键词： Keyword: self-flux method yellow phosphor luminescence LED rare earths

红外热成像对手法治疗动力性颈椎管狭窄症的临床评价意义

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中国现代医生 2008年第35期46卷 1-2页

作者：王军郑志新王刚侯京山解放军总医院康复医学科北京100853

目的探讨远红外热成像检查对手法治疗动力性颈椎管狭窄症临床效果的评价的意义。方法对18例临床诊断为动力性颈椎管狭窄症的患者进行手法治疗前、后红外热成像的检查,运用配对t检验的方法进行统计学分析。结果治疗前后颈、肩、背部两侧... 详细信息

目的探讨远红外热成像检查对手法治疗动力性颈椎管狭窄症临床效果的评价的意义。方法对18例临床诊断为动力性颈椎管狭窄症的患者进行手法治疗前、后红外热成像的检查,运用配对t检验的方法进行统计学分析。结果治疗前后颈、肩、背部两侧温度的比较值有统计学意义(t=3.083,ν=17,P<0.05)。结论远红外热成像检查可较好地反映手法治疗动力性颈椎管狭窄颈、项、肩、背软组织疼痛征血供状态与症状改善的变化,为临床疗效评价提供客观依据。

关键词：红外热成像手法颈椎管狭窄疼痛疗效评价

Effects of guanidinium cations on structural,optoelectronic and photovoltaic properties of perovskites

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Journal of Energy Chemistry 2021年第7期30卷 48-54页

作者： Yi Ding Yan Wu Ying Tian Yuzeng Xu Minna hou Bo Zhou jingshan Luo Guofu hou Ying Zhao Xiaodan Zhang Institute of Photoelectronic Thin Film Devices and Technolog Key Laboratory of Photoelectronic Thin Film Devices and Technology(Tianjin)Engineering Research Center of Thin Film Photoelectronic Technology(Ministry of Education)Renewable Energy Conversion and Storage CenterNankai UniversityTianjin 300072China Institute of Modern Physics Shaanxi Key Laboratory for Theoretical Physics FrontiersNorthwest UniversityXi’an 710069ShaanxiChina

Guanidinium(GA)cations are intentionally introduced in MAPbI_(3) perovskite by considering its potential capability of stabilizing the material through plenty of hydrogen bonds and mitigating hysteresis because of the zero dipole *** configurations of GA cation in film and its effects on structural,optoelectronic and photovoltaic properties of perovskite have been comprehensively studied by systematically modulating the GA *** has been demonstrated that moderate GA cations can effectively passivate the defect surrounding perovskite grains,yielding an enhanced efficiency as high as~19,2%in a p-i-n type planar solar cells with the GA ratio of 15%.Further increasing the GA ratio deteriorates device performance,as extra GA cations hinder grain growth and thus reduce the grain size,which facilitates the defect generation around the enhanced ***,a new two-dimensional(2 D)layered perovskite phase that features alternating GA and MA cations in the interlayer space(ACI)appears ultimately,while the ACI phase typically suffers from slow charge transportation across the parallel PbI2 octahedral layers separated by large A-site cations.

关键词： Perovskite solar cell Guanidinium DFT calculations 2D perovskite Phase separation

UV light absorbers executing synergistic effects of passivating defects and improving photostability for efficient perovskite photovoltaics

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Journal of Energy Chemistry 2022年第4期31卷 138-146页

作者： Jiale Li Wenjing Qi Yameng Li Sumin Jiao Hao Ling Peng Wang Xin Zhou Khumal Sohail Guangcai Wang Guofu hou jingshan Luo Ying Zhao Liming Ding Yuelong Li Xiaodan Zhang Institute of Photoelectronic Thin Film Devices and Technology Key Laboratory of Photoelectronic Thin Film Devices and Technology of TianjinEngineering Research Center of Thin Film Optoelectronics Technology(MoE)Nankai UniversityTianjin 300350China College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018HebeiChina Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

Metal halide perovskite-based solar cells(PSCs) have rapidly-increased power conversion efficiency(PCE)exceeding 25% but poor stability especially under ultraviolet(UV) light. Meanwhile, non-radiative recombination caused by diverse defects in perovskite absorbers and related interfaces is one of the major factors confining further development of PSCs. In this study, we systematically investigate the role of 2-(2-hydroxy-5-methylphenyl)benzotriazole(UVP) additive in perovskite layers. By adjusting the amount of doped UVP, the quality of perovskite absorbers is significantly improved with enlarged grains, longer lifetime and diffusion length of charge carriers. Furthermore, UVP not only reduces defects for less nonradiative recombination, but also matches energy level alignment for efficient interfacial charge extraction. X-ray photoelectron spectroscopy confirms that N-donor of UVP molecule coordinates with undercoordinated Pb^(2+) on the surface. Interestingly, UVP incorporated in PbI_(2) protects the perovskite by absorbing UV through the opening and closing of the chelating ring. Eventually, the UVP treated PSCs obtain a champion PCE of 22.46% with remarkably enhanced UV stability, retaining over 90% of initial PCE after 60 m W/cm^(2) strong UV irradiation for 9 h while the control maintaining only 74%. These results demonstrate a promising strategy fabricating passivated and UV-resistant perovskite materials simultaneously for efficient and stable perovskite photovoltaics.

关键词： Planar perovskite solar cells 2-(2-Hydroxy-5-methylphenyl)benzotria zole Passivation UV stability

Robust Face Recognition Based on Non-negative Sparse Discriminative Low-rank Representation

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Robust Face Recognition Based on Non-negative Sparse Discrim...

第30届中国控制与决策会议

作者： Xielian hou Caikou Chen Shengwei Zhou jingshan Li College of Information Engineering Yangzhou University

Due to occlusion or camouflage existing in the current face images,previous face recognition algorithms such as sparse representation classification algorithm do not take face damage into consideration during the training period,and therefore their testing performance will be *** this paper,we propose a novel non-negative sparse discriminative low-rank representation algorithm（NSDLRR）.First,we seek a sparse,low-rank and non-negative matrix in training ***,we add a structural inconsistency constraint on this basis,make different kinds of samples as independent as possible,thereby increasing the extra recognition ***,the test samples are classified by sparse linear *** results on different face database show that the algorithm has better performance.

关键词： Low-rank representation Sparse representation Structural inconsistency

来源： cnki会议评论

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cnki会议

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一种普及计算环境中统一传输网络UTN

计算机工程 2005年第12期31卷 116-118页

作者：李景山侯紫峰罗予晋黄景楠中国科学院计算技术研究所中国科学院研究生院北京100039 联想研究院北京100085 联想研究院

提出了一种普及计算环境中统一传输网络UTN(UniformTransportNetwork),该统一传输网络实现了以DeviceID作为设备的唯一标识的通信地址,DeviceID的地址到具体的传输地址的映射、多传输协议之间的路由和转换问题、实现进程之间可靠的单播... 详细信息

提出了一种普及计算环境中统一传输网络UTN(UniformTransportNetwork),该统一传输网络实现了以DeviceID作为设备的唯一标识的通信地址,DeviceID的地址到具体的传输地址的映射、多传输协议之间的路由和转换问题、实现进程之间可靠的单播、组播通信。该统一传输网络为普及计算环境中多种设备之间互联互通提供了必要的技术支持。

关键词：普及计算传输协议路由地址映射

论大运河工业遗产再利用嵌入大运河国家文化公园建设的路径与策略

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建筑实践 2024年第6期 28-36页

作者：韩晗侯渝宁曹福然 WANG jingshan 武汉大学景园规划设计研究院武汉大学国家文化发展研究院浙大城市学院浙江省大运河文化研究院

1引言2023年9月20日,习近平总书记在浙江省绍兴市考察。下午,他来到浙东运河文化园,认真了解了古运河发展演变历史和大运河保护及大运河国家文化公园建设等情况。习近平总书记对大运河文化建设高度重视,曾多次对大运河的保护、传承、利...

1引言2023年9月20日,习近平总书记在浙江省绍兴市考察。下午,他来到浙东运河文化园,认真了解了古运河发展演变历史和大运河保护及大运河国家文化公园建设等情况。习近平总书记对大运河文化建设高度重视,曾多次对大运河的保护、传承、利用作出指示,指出“要古为今用,深入挖掘以大运河为核心的历史文化资源”。中国大运河,是中国古代劳动人民创造的一项伟大工程,是世界上最长的人工河流,也是中国古代南北交通的大动脉。

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