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Synergic action of linear dispersion, second-order nonlinearity, and third-order nonlinearity in shaping the spectral profile of a femtosecond pulse transporting in a lithium niobate crystal

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Photonics Research 2024年第4期12卷 774-783页

作者： LIHONG HONG yuanyuan liu ZHI-YUAN LI State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

We present a detailed theoretical and numerical analysis on the temporal-spectral-spatial evolution of a highpeak-power femtosecond laser pulse in two sets of systems:a pure lithium niobate(LN)plate and a periodically poled lithium niobate(PPLN)*** develop a modified unidimensional pulse propagation model that considers all the prominent linear and nonlinear processes and carried out the simulation process based on an improved split-step Fourier transformation *** theoretically analyze the synergic action of the linear dispersion effect,the second-order nonlinearity(2nd-NL)second-harmonic generation(SHG)effect,and the third-order nonlinearity(3rd-NL)self-phase modulation(SPM)effect,and clarify the physical mechanism underlying the peculiar and diverse spectral broadening patterns previously reported in LN and PPLN thin plate *** analysis and discussion provides a deeper insight into the synergetic contribution of these linear and nonlinear effects brought about by the interaction of a femtosecond laser pulse with the LN nonlinear crystal and helps to draw a picture to fully understand these fruitful optical physical processes,phenomena,and laws.

关键词： pulse nonlinearity lithium

Tuning the crystalline and electronic structure of ZrO_(2)via oxygen vacancies and nano-structuring for polysulfides conversion in lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第1期88卷 82-93,I0003页

作者： Shengnan Fu Chaowei Hu Jing Li Hongtao Cui yuanyuan liu Kaihua liu Yanzhao Yang Meiri Wang Shandong Key Laboratory for Chemical Engineering and Processing School of Chemistry&Chemical EngineeringYantai UniversityYantai 264000ShandongChina Key Laboratory for Special Functional Aggregate Materials of Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100ShandongChina

The recent emergence of tetragonal phases zirconium dioxide(ZrO_(2))with vacancies has generated significant interest as a highly efficient and stable electrocatalyst with potential applications in trapping polysulfides and facilitating rapid conversion in lithium-sulfur batteries(LSBs).However,the reduction of ZrO_(2)is challenging,even under strong reducing atmospheres at high temperatures and ***,the limited presence of oxygen vacancies results in insufficient active sites and reaction interfaces,thereby hindering practical ***,we successfully introduced abundant oxygen vacancies into ZrO_(2)at the nanoscale with the help of carbon nanotubes(CNTs-OH)through hydrogen-etching at lower temperatures and *** introduced oxygen vacancies on ZrO_(2-x)/CNTs-OH can effectively rearrange charge distribution,enhance sulfiphilicity and increase active sites,contributing to high ionic and electronic transfer kinetics,strong binding energy and low redox barriers between polysulfides and ZrO_(2-x).These findings have been experimentally validated and supported by theory *** a result,LSBs assembled with the ZrO_(2-x)/CNTs-OH modified separators demonstrate excellent rate performance,superior cycling stability,and ultra-high sulfur ***,at high sulfur loading of 6 mg cm^(-2),the area capacity is still up to 6.3 mA h cm^(-2).This work provides valuable insights into the structural and functional optimization of electrocatalysts for batteries.

关键词： Lithium-sulfur batteries Oxygen vacancies Zirconium dioxide/carbon nanotubes with–OH Improved redox kinetics Superior cycling stability

Intense and Superflat White Laser with 700-nm 3-dB Bandwidth and 1-mJ Pulse Energy Enabling Single-Shot Subpicosecond Pulse Laser Spectroscopy

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Research 2024年第2期6卷 319-327页

作者： Lihong Hong Haiyao Yang Liqiang liu Mingzhou Li yuanyuan liu Baoqin Chen Huakang Yu Wenbo Ju Zhi-Yuan Li School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640China

An optical spectrometer is a basic spectral instrument that probes microscopic physical and chemical properties of macroscopic objects but generally suffers from difficulty in broadband time-resolved *** this work,we report the creation of ultrabroadband white-light laser with a 3-dB bandwidth covering 385 to 1,080 nm,pulse energy of 1.07 mJ,and pulse duration of several hundred femtoseconds by passing 3-mJ pulse energy,50-fs pulse duration Ti:Sapphire pulse laser through a cascaded fused silica plate and chirped periodically poled lithium niobate *** utilize this unprecedented superflat,ultrabroadband,and intense femtosecond laser light source to build a single-shot(i.e.,single-pulse)subpicosecond pulse laser ultraviolet-visible-near-infrared spectrometer and successfully measure various atomic and molecular absorption *** single-shot ultrafast spectrometer may open up a frontier to monitor simultaneously the ultrafast dynamics of multiple physical and chemical processes in various microscopic systems.

关键词： Pulse utilize frontier

Performance Analysis of an Efficient Integration System of Coal-Fired Power Plant,Solar Thermal Energy and CO_(2)Capture

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Journal of Thermal Science 2024年第4期33卷 1509-1522页

作者： WANG Yuhao WANG Ruilin liu Lanhua XING Chenjian GUO Yafei YANG Qingshan YING Jiaheng SUN Jian LI Wenjia liu yuanyuan ZHAO Chuanwen School of Energy and Mechanical Engineering Nanjing Normal UniversityNanjing210023China China Huadian Group Co.LTD.Shanghai Branch Shanghai200120China Key Laboratory of Efficient Utilization of Low and Medium Grade Energy(Tianjin University) Ministry of Education of ChinaTianjin300350China Huadian Zhengzhou Mechanical Design Institute Company Limited Zhengzhou450046China

Coal-fired power plant is a major contributor to greenhouse gas *** post-combustion capture is a promising method for CO_(2)emission reduction but the high thermal demand is *** address this issue,solar thermal energy and CO_(2)capture are jointly integrated into the coal-fired power plant in this *** solar thermal energy is employed to meet the heat requirement of the CO_(2)capture process,thereby avoiding the electricity loss caused by self-driven CO_(2)***,the heat released from the carbonation reaction of MgO adsorbent is integrated into the steam Rankine *** partially substituting the extracted steam for feedwater heating,the electricity output of the power plant is further *** to the results from the developed model,the system could achieve a CO_(2)capture rate of 86.5%and an electricity output enhancement of 9.8%compared to the reference system,which consists of a self-driven CO_(2)capture coal-fired power plant and PV generation *** operational strategy is also optimized and the amount of CO_(2)emission reduction on a typical day is increased by 11.06%.This work shows a way to combine fossil fuels and renewable energy for low carbon emissions and efficient power generation.

关键词： CO_(2)capture parabolic trough collector solar aided coal-fired electricity generation

Acute Effects of Exposure to Fine Particulate Matter and Its Constituents on Sex Hormone Among Postmenopausal Women — Beijing, Tianjin, and Hebei PLADs, China, 2018–2019

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China CDC weekly 2024年第13期6卷 249-253,I0001-I0004页

作者： Yanlin Tian Jiaonan Wang Jianlong Fang Chen Chen Feng Zhao Yi Zhang Peng Du Yawei Li Wanying Shi yuanyuan liu Enmin Ding Song Tang Xu Yue Xiaoming Shi Chinese Research Academy of Environmental Sciences BeijingChina Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control(AEMPC)Nanjing University of Information Science&TechnologyNanjing CityJiangsu ProvinceChina China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina Department of Epidemiology and Health Statistics School of Public HealthCapital Medical Universityand Beijing Municipal Key Laboratory of Clinical EpidemiologyBeijingChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina

What is already known on this topic?Exposure to fine particulate matter(PM2.5)was linked to endocrine hormone disruption in the reproductive ***,it was unclear which specific components of PM2.5 were primarily responsible for these *** is added by this report?The study presented the initial epidemiological evidence that brief exposure to PM2.5 can elevate estradiol levels in postmenopausal *** particle components had unique effects,with watersoluble ions and specific inorganic elements like Ag,As,Cd,Hg,Ni,Sb,Se,Sn,and Tl potentially playing significant roles in increasing estradiol *** are the implications for public health practice?The study established that the prevalence of air pollution,along with its specific components,has been recognized as a novel risk factor affecting the balance of sex hormones.

关键词： pollution Particulate primarily

Single-atom modified graphene cocatalyst for enhanced photocatalytic CO_(2)reduction on halide perovskite

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Chinese Journal of Catalysis 2024年第9期64卷 143-151页

作者： Hui Fu Jin Tian Qianqian Zhang Zhaoke Zheng Hefeng Cheng yuanyuan liu Baibiao Huang Peng Wang State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100ShandongChina

Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2)reduction owing to the wide light absorption range,negative conduction band position and high reduction ***,photoreduction of CO_(2)by MHP remains a challenge because of the slow charge separation and ***,a cobalt single-atom modified nitrogen-doped graphene(Co-NG)cocatalyst is prepared for enhanced photocatalytic CO_(2)reduction of bismuth-based MHP Cs_(3)Bi_(2)Br_(9).The optimal Cs_(3)Bi_(2)Br_(9)/Co-NG composite exhibits the CO production rate of 123.16μmol g-1 h-1,which is 17.3 times higher than that of Cs_(3)Bi_(2)Br_(9).Moreover,the Cs_(3)Bi_(2)Br_(9)/Co-NG composite photocatalyst exhibits nearly 100%CO selectivity as well as impressive long-term *** carrier dynamic characterizations such as Kelvin probe force microscopy(KPFM),single-particle PL microscope and transient absorption(TA)spectroscopy demonstrate the vital role of Co-NG cocatalyst in accelerating the transfer and separation of photogenerated charges and improving photocatalytic *** reaction mechanism has been demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy *** addition,in situ X-ray photoelectron spectroscopy test and theoretical calculation reveal the reaction reactive sites and reaction energy barriers,demonstrating that the introduction of Co-NG promotes the formation of~(*)COOH intermediate,providing sufficient evidence for the highly selective generation of *** work provides an effective single-atom-based cocatalyst modification strategy for photocatalytic CO_(2)reduction and is expected to shed light on other photocatalytic applications.

关键词： Bismuth-based perovskite Photocatalysis CO_(2)reduction Single-atom cocatalyst Charge separation

Statement on Establishment of Public Health Protection Guideline for Cold Spells—China

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China CDC weekly 2024年第5期6卷 92-94页

作者： Tiantian Li Qinghua Sun Chen Chen Qing Wang Jie Ban Runmei Ma Yi Zhang Lijun Pan yuanyuan liu Qiutong Li Leyao Chang Hanshuo Zhang Yirong liu Miaoyou Niu Xiangxiang Wei Lin Wang China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina

Cold spells are extreme weather events characterized by the invasion of cold air from high latitudes into the middle and low latitudes,resulting in significant *** spells have various adverse health effects,including epidermal damage,respiratory tract spasms,respiratory immune abnormalities,acute cardiopulmonary diseases,and exacerbation of urinary and endocrine *** response to the frequent cold spells in recent years.

关键词： respiratory invasion acute

Glycnsisitin A:A promising bicyclic peptide against heart failure that facilitates TFRCmediated uptake of iron in cardiomyocytes

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Acta Pharmaceutica Sinica B 2024年第7期14卷 3125-3139页

作者： Jichao Zhou yuanyuan liu Xiaoli Wei Meng Yuan Xu Zhang Lingfeng Qin Bing Cui Pingping Li Jing Zhang Ziming Feng Jianshuang Jiang Xiang Yuan Ruibing Xu Zhimeng Zhang Peicheng Zhang Xiaowei Zhang Yanan Yang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Zhigancao decoction is a traditional prescription for treating irregular pulse and palpitations in *** the monarch drug of Zhigancao decoction,the bioactive molecules of licorice against heart diseases remain *** established the HRESIMS-guided method leading to the isolation of three novel bicyclic peptides,glycnsisitins A-C(1-3),with distinctive C-C and C-O-C side-chain-toside-chain linkages from the roots of Glycyrrhiza uralensis(Licorice).Glycnsisitin A demonstrated stronger cardioprotective activity than glycnsisitins B and C in an in vitro model of doxorubicin(DOX)-induced cardiomyocyte *** A treatment not only reduced the mortality of heart failure(HF)mice in a dose-dependent manner but also significantly attenuated DOX-induced cardiac dysfunction and myocardial *** set enrichment analysis(GSEA)of the differentially expressed genes indicated that the cardioprotective effect of glycnsisitin A was mainly attributed to its ability to maintain iron homeostasis in the ***,glycnsisitin A interacted with transferrin and facilitated its binding to the transferrin receptor(TFRC),which caused increased uptake of iron in *** findings highlight the key role of bicyclic peptides as bioactive molecules of Zhigancao decoction for the treatment of HF,and glycnsisitin A constitutes a promising therapeutic agent for the treatment of HF.

关键词： Glycyrrhiza uralensis Bicyclic peptides Myocardial energy metabolism Iron homeostasis TFRC

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微博用户和热点话题间的社交吸引法则研究

情报杂志 2024年第8期43卷 113-123页

作者：安璐刘媛圆武汉大学信息资源研究中心武汉430072 武汉大学信息管理学院武汉430072

[研究目的]探究微博用户和热点话题间社交吸引力的内在作用机制有助于深入理解社交吸引力的决定因素和热门话题的流行成因。[研究方法]以2022年微博平台的7类14个热点话题为研究对象,从用户行为视角构造用户与热点话题之间的吸引力测算... 详细信息

[研究目的]探究微博用户和热点话题间社交吸引力的内在作用机制有助于深入理解社交吸引力的决定因素和热门话题的流行成因。[研究方法]以2022年微博平台的7类14个热点话题为研究对象,从用户行为视角构造用户与热点话题之间的吸引力测算公式,从话题、用户、距离、环境属性出发,确定影响社交吸引力的23个指标。采用4种机器学习模型构建吸引力的影响因素模型,利用SHAP模型对结果最好的模型XGBoost进行解释,分析各项特征的贡献大小和相互影响关系。[研究结论]研究发现,用户属性的重要性非常明显,环境属性对社交吸引力基本没有显著贡献。在实践中,必要的高影响媒体转发造势、更多的话题上榜时间和更具有情感倾向的话题名称能带来更大的社交吸引力,帮助塑造与推进有益的热点话题,也为政府引导网络空间话题的健康发展提供决策参考。

关键词：微博热点话题社交媒体用户社交吸引力 SHAP