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Mechanism of signal uncertainty generation for laser-induced breakdown spectroscopy

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Frontiers of physics 2021年第2期16卷 35-44页

作者： Yang-Ting Fu Wei-Lun Gu zong-yu hou Sher Afgan Muhammed Tian-Qi Li yun Wang Zhe Wang State Key Lab of Power Systems International Joint Laboratory on Low Carbon Clean EnergyInnovationDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Renewable Energy Resources Laboratory(RERL)&National Fuel Cell Research Center Department of Mechanical and Aerospace EngineeringThe University of CaliforniaIrvineCA 92697-3975USA

Relatively large measurement uncertainty severely hindered wide application for laser-induced breakdown spectroscopy(LIBS),therefore it is of great importance to understand the mechanism of signal uncertainty generation,including initiation and *** has been found that the Auctuation of plasma morphology was the main reason for signal ***,it still remains unclear what mechanism leads to laser-induced plasma morphology *** the present work,we employed three fast-imaging cameras to capture three successive plasma images fromn a same laser-induced Titanium alloy plasma,which enables us to understand more clearly of the plasma evolution process especially for the early plasma evolution stage when plasma and surrounding gases interact *** from the images,the plasma experienced an increasing morphological fuctuation as delay time increased,transforming from a“stable plasma”before the delay time of 100 ns to a“fuctuating plasma”after the delay time of 300 ***,the frontier part of plasma showed a significant down-ward motion from the delay time of 150 ns to 200 ns and crashed with the lower part of the plasma,making the plasma fatter and later even splitting the plasma into two parts,which was considered as a critical process for the transformation of“stable plasma”to“unstable plasma”.By calculating the correlation coefficient of plasma image pairs at successive delay times,it was found that the higher the similarity between two plasma at early stage,the more similar at later stage;this implied that the tiny plasma fuctuation earlier than the critical delay time(150-200 ns)was amplifed,causing a large plasma fluctuation at the later stage as well as LIBS measurement *** initation of slight fluctuation was linked with Rayleigh-Taylor Instability(RTI)due to the drastic material interpenetration at the plasma-ambient gas interface at earlier stage(before 50 ns).That is,the uncertainty generation of LIBS was p

关键词： LIBS laser-induced breakdown spectroscopy signal uncertainty Rayleigh-Taylor instability

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Major elements analysis in bituminous coals under different ambient gases by laser-induced breakdown spectroscopy with PLS modeling

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Frontiers of physics 2012年第6期7卷 708-713页

作者： Zhe Wang Ting-Bi yuan Siu-Lung Lui zong-yu hou Xiong-Wei Li Zheng Li Wei-Dou Ni State Key Lab of Power Systems Department of Thermal EngineeringTsinghua-BP Clean Energy CenterTsinghua UniversityBeijing 100084China

Three major elements, carbon, hydrogen, and nitrogen, in twenty-four bituminous coal samples, were measured by laser-induced breakdown spectroscopy. Argon and helium were applied as ambient gas to enhance the signals and eliminate the interference of nitrogen from surrounding air. The relative standard deviation of the related emission lines and the performance in the partial least squares （PLS） modeling were compared for different ambient environments. The results showed that argon not only improved the intensity, but also reduced signal fluctuation. The PLS model also had the optimal performance in multi-element analysis using argon as ambient gas. The root mean square error of prediction of carbon concentration decreased from 4.25% in air to 3.49% in argon, while the average relative error reduced from 4.96% to 2.98%. Hydrogen line demonstrated similar improvement. Yet, the nitrogen lines were too weak to be detected even in an argon environment which suggested the nitrogen signal measured in air come from the breakdown of nitrogen molecules in the atmosphere.

关键词： laser-induced breakdown spectroscopy (LIBS) ambient gas bituminous coal partial least squares (PLS) relative standard deviations (RSD)

Laser-induced breakdown spectroscopy in China

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Frontiers of physics 2014年第4期9卷 419-438页

作者： Zhe Wang Ting-Bi yuan zong-yu hou Wei-Dong Zhou Ji-Dong Lu Hong-Bin Ding Xiao-Yan Zeng State Key Lab of Power Systems Department of Thermal Engineering Tsinghua-BP Clean Energy Center Tsinghua University Beijing 100084 China Institute of Information Optics Zhejiang Normal University Jinhua 321004 China School of Electric Power South China University of Technology Guangzhou 510640 China School of Physics and Optoelectronic Engineering Dalian University of Technology Dalian 116024 China School of Optical and Electronic Information Huazhong University of Science Technology Wuhan 430074 China

Laser-induced breakdown spectroscopy （LIBS） has been regarded as a future superstar for chemical analysis for years due to its unique features such as little or no sample preparation, remote sensing, and fast and multi-element analysis. Chinese LIBS comnmnity is one of the most dynamically developing communities in the World. The aim of the work is to inspect what have been done in China for LIBS development and, based on the understanding of the overall status, to identify the challenges and opportunities for the future development. In this paper, the scientific contributions from Chinese LIBS comlnunity are reviewed for the following four aspects： fimdamentals, instrumentation, data processing and modeling, and applications; and the driving force of LIBS development in China is analyzed, the critical issues for successful LIBS application are discussed, and in our opinion, the potential direction to improve the technology and to realize large scale commercialization in China is proposed.

关键词： laser-induced breakdown spectroscopy laser-induced breakdown spectroscopy (LIBS),quantitative analysis signal enhancement application coal metal environment energy

Development in the application of laser-induced breakdown spectroscopy in recent years:A review

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Frontiers of physics 2021年第2期16卷 45-69页

作者： Lian-Bo Guo Deng Zhang Lan-Xiang Sun Shun-Chun Yao Lei Zhang Zhen-Zhen Wang Qian-Qian Wang Hong-Bin Ding yuan Lu zong-yu hou Zhe Wang Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesSheyang 110016China School of Electric Power South China University of TechnologyGuangzhou 510640China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China Key Laboratory of Photonic Information Technology School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China School of Physics Dalian University of TechnologyNo.2 Linggong RoadGanjingzi DistrictDalian 116024China Optics and Optoelectronics Laboratory Ocean University of ChinaQingdao 266100China State Key Lab of Power Systems Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

Laser-induced breakdown spectroscopy(LIBS)has been widely studied due to its unique advantages such as remote sensing,real-time multi-elemental detection and none-to-little *** the efforts of researchers around the world,LIBS has been developed by leaps and ***,in recent years,more and more Chinese LIBS researchers have put tremendous energy in promoting LIBS *** is worth mentioning that the application of LIBS in a specific field has its special application background and technical difficulties,therefore it may develop in different stages.A review summarizing the current development status of LIBS in various fields would be helpful for the development of LIBS technology as well as its applications especially for Chinese LIBS community since most of the researchers in this field work in *** the present work,we summarized the research status and latest progress of main research groups in coal,metallurgy,and water,*** on the current research status,the challenges and opportunities of LIBS were evaluated,and suggestions were made to further promote LIBS applications.

关键词： laser-induced breakdown spectroscopy application

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Luminescence: a new perspective for investigating perovskite precursors

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Science China Materials 2025年第01期 312-313页

作者： Haofeng Zheng Shaocong hou School of Electrical Engineering and Automation Wuhan University Wuhan University Shenzhen Research Institute

In the past two decades, perovskite materials have made significant progress in optoelectronic semiconductors, emerging as formidable candidates for the next generation of commercial solar cells, light-emitting diodes (LEDs), and *** the fundamental solution chemistry and photophysics in solution-processed perovskite devices is crucial for comprehending to achieve highly efficient optoelectronic devices.

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Multi-model ensemble learning for battery state-of-health estimation:Recent advances and perspectives

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Journal of Energy Chemistry 2025年第1期100卷 739-759页

作者： Chuanping Lin Jun Xu Delong Jiang Jiayang hou Ying Liang Zhongyue Zou Xuesong Mei State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi'an Jiaotong University Department of Electrical Engineering and Automation Luoyang Institute of Science and Technology School of Mechanical Engineering Hangzhou Dianzi University

The burgeoning market for lithium-ion batteries has stimulated a growing need for more reliable battery performance monitoring. Accurate state-of-health(SOH) estimation is critical for ensuring battery operational performance. Despite numerous data-driven methods reported in existing research for battery SOH estimation, these methods often exhibit inconsistent performance across different application scenarios. To address this issue and overcome the performance limitations of individual data-driven models,integrating multiple models for SOH estimation has received considerable attention. Ensemble learning(EL) typically leverages the strengths of multiple base models to achieve more robust and accurate outputs. However, the lack of a clear review of current research hinders the further development of ensemble methods in SOH estimation. Therefore, this paper comprehensively reviews multi-model ensemble learning methods for battery SOH estimation. First, existing ensemble methods are systematically categorized into 6 classes based on their combination strategies. Different realizations and underlying connections are meticulously analyzed for each category of EL methods, highlighting distinctions, innovations, and typical applications. Subsequently, these ensemble methods are comprehensively compared in terms of base models, combination strategies, and publication trends. Evaluations across 6 dimensions underscore the outstanding performance of stacking-based ensemble methods. Following this, these ensemble methods are further inspected from the perspectives of weighted ensemble and diversity, aiming to inspire potential approaches for enhancing ensemble performance. Moreover, addressing challenges such as base model selection, measuring model robustness and uncertainty, and interpretability of ensemble models in practical applications is emphasized. Finally, future research prospects are outlined, specifically noting that deep learning ensemble is poised to advance ens

关键词： Lithium-ion battery State-of-health estimation Data-driven Machine learning Ensemble learning Ensemble diversity

Practical approach for detecting k-nonseparability of multipartite quantum states

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 32-48页

作者： Jie Guo Jinchuan hou Xiaofei Qi Kan He College of Mathematics Taiyuan University of Technology School of Mathematics and Statistics Shanxi University Key Laboratory of Complex Systems and Data Science of Ministry of Education Shanxi University

The instantaneous detection of entanglement in quantum states poses a significant challenge in the fields of quantum computation and quantum information, and there are no practical methods or tools to complete this task satisfactorily so far. We propose a sufficient and necessary criterion of k-nonseparability for any n-partite finite or infinite dimensional systems, 2 ≤ k ≤ n. This criterion serves as the foundation for a practical scheme designed to detect entanglement and k-nonseparability across multipartite finite-dimensional systems. To exemplify the application of our scheme, we have developed a software tool that facilitates swift and precise identification of entanglement, k-nonseparability, and genuine entanglement within n-qubit systems, specifically tailored for systems with 2 ≤ n ≤ 4.

关键词： multipartite systems entanglement states entanglement witnesses ${\bm~k}$-nonseparability

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Milking the Market

China Today 2025年第1期74卷 39-41页

作者： hou JUAN China Economic Weekly

With climate change becoming direr and the WTO losing its teeth at 30,experts renew call for green collaboration among the world’s three largest *** competition intensifies in the global dairy product market,many foreign dairy companies are focusing on China."China is the best market to debut breakthrough products,"said Bruno Chevot,food and beverage multinational Danone China’s president for North Asia and Oceania.

关键词： companies Market China.

Low-temperature chlorination roasting technology for the simultaneous recovery of valuable metals from spent LiCoO_(2)cathode material

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 80-91页

作者： Junjie Shi Changle hou Jingjing Dong Dong Chen Jianzhong Li Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

With the continuous increase in the disposal volume of spent lithium-ion batteries(LIBs),properly recycling spent LIBs has become essential for the advancement of the circular *** study presents a systematic analysis of the chlorination roasting kinetics and proposes a new two-step chlorination roasting process that integrates thermodynamics for the recycling of LIB cathode *** activation energy for the chloride reaction was 88.41 kJ/mol according to thermogravimetric analysis–derivative thermogravimetry data obtained by using model-free,model-fitting,and Z(α)function(αis conversion rate).Results indicated that the reaction was dominated by the first-order(F1)model when the conversion rate was less than or equal to 0.5 and shifted to the second-order(F2)model when the conversion rate exceeded *** conditions were determined by thoroughly investigating the effects of roasting temperature,roasting time,and the mass ratio of NH_(4)Cl to LiCoO_(2).Under the optimal conditions,namely 400℃,20 min,and NH_(4)Cl/LiCoO_(2)mass ratio of 3:1,the leaching efficiency of Li and Co reached 99.43% and 99.05%,*** of the roasted products revealed that valuable metals in LiCoO_(2)transformed into CoCl_(2) and ***,the reaction mechanism was elucidated,providing insights for the establishment of a novel low-temperature chlorination roasting technology based on a crystal structure *** technology can guide the development of LIB recycling processes with low energy consumption,low secondary pollution,high recovery efficiency,and high added value.

关键词： spent lithium-ion battery thermodynamics chlorination roasting kinetics circular economy

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