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Analysis of the element content in poplar tree leaves by femtosecond laser-induced breakdown spectroscopy

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 1953-1957页

作者： MA Shuang GAO Xun GUO KaiMin KAHSAY Medhanie lin jingquan School of Science Changchun University of Science and Technology Changchun 130022 China International Joint Research Centerfbr Nanophotonics and Biophotonics Changchun University of Science and Technology Changchun 130022 China

Femtosecond laser-induced breakdown spectroscopy (fs-LIBS) is employed to analyze the element content in poplar tree leaves from four representative locations in Changchun City (Jingyue National Forest Park,JYP),Changchun University of Science and Technology (CUST),Casting Factory (CF) and Forging Factory (FF) of First Automobile Works (FAW) under identical experimental *** elements of N,P,K,Ca,Fe,Ti,Mn and Na are identified in the poplar tree leaves from the recorded spectrogram and the elemental content in the leaves is further obtained by applying free calibration method to the *** results show that the elements Ca and Fe in the poplar tree leaves from the CF area have the highest concentration in the four locations,which is a factor of 2.05 and 1.66 respectively to those of *** experiment demon-strates that fs-LIBS can be utilized to analyze element content in a sample and find new applications in the environmental detection.

关键词： femtosecond laser laser-induced breakdown spectroscopy poplar tree leaf quantitative analysis

Combined effects of ambient gas pressures and magnetic field on laser plasma expansion dynamics

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Plasma Science and Technology 2017年第1期19卷 79-84页

作者： Atif HUSSAIN Xun GAO Qi LI Zuoqiang HAO jingquan lin School of Science Changchun University of Science and Technology Changchun 130022 People＇s Republic of China

In this work,we investigated the influence of air gas pressures on the expansion features of nanosecond laser ablated aluminum plasma in the absence and presence of a nonuniform magnetic field using fast photography.A particular emphasis was given to the plume dynamics（shape,size） with the combined effects of ambient gas pressures and an external magnetic *** expansion,sharpening effect,and hemi-spherical structures of the aluminum plasma were observed without a magnetic field under different gas *** of the resulting plume images with the combined effects of air gas pressures and a magnetic field show significant changes,such as plume splitting,elliptical geometry changes,radial expansion,and plume ***,the total size of the plasma plume with a magnetic field was measured to be smaller than the plasma plume without a magnetic field at several background pressures.

关键词： magnetic field air pressure expansion plume front propagation

光谱预处理小波基函数的选择对结合FIBS技术和机器学习的铝合金识别精确度影响研究

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激光杂志 2024年第6期45卷 88-93页

作者：于海龙高宇瑾谢云双杨硕汤宇轩高勋林景全长春理工大学物理学院长春130022 长春理工大学中山研究院广东中山528400

随着经济不断发展,工业建筑领域产生了大量的废弃铝合金材料,对废弃铝合金材料分类回收可以提升废弃资源的利用效率,缓解能源紧张。选取了工业领域常用的五种型号的铝合金,开展了等离子体丝诱导击穿光谱(FIBS)光谱预处理小波变换基函数... 详细信息

随着经济不断发展,工业建筑领域产生了大量的废弃铝合金材料,对废弃铝合金材料分类回收可以提升废弃资源的利用效率,缓解能源紧张。选取了工业领域常用的五种型号的铝合金,开展了等离子体丝诱导击穿光谱(FIBS)光谱预处理小波变换基函数对铝合金分类识别精度的影响的研究。分别采用bior2.2、bior2.4和bior2.6正交小波基函数对铝合金的FIBS光谱进行预处理,结合线性判别分析(LDA)、网格搜索优化的支持向量机(GSSVM)和反向传播神经网络(BPNN)实现了铝合金型号的快速分类识别。结果表明bior2.2、bior2.4和bior2.6正交小波基函数结合LDA-GSSVM实现铝合金型号的平均识别准确率为90%、100%和76.67%,结合LDA-BPNN实现铝合金型号的平均识别准确率为96.67%、100%和90%,因此选择合适的正交小波基函数对FIBS光谱预处理,对于提高铝合金型号识别准确率有较大作用。

关键词： FIBS 正交小波基函数线性判别分析分类识别铝合金材料

Ultrafast plasmon dynamics in asymmetric gold nanodimers

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Chinese Physics B 2022年第6期31卷 387-395页

作者： Bereket Dalga Dana Alemayehu Nana Koya Xiaowei Song jingquan lin School of Science Changchun University of Science and TechnologyChangchun 130022China Department of Physics College of Natural and Computational SciencesWolaita Sodo UniversityP.O.Box 138Wlaita SodoEthiopia

We theoretically investigate the effect of symmetry breaking on the ultrafast plasmon responses of Au nanodisk(ND)dimers by varying the diameter of one of the constituent *** the case of a single ultrafast laser pulse,we demonstrate that the ultrafast responses of Au ND homodimer can be significantly modified due to the effect of symmetry *** symmetric dimer shows a single broad spectral peak,whereas the size-asymmetric dimer shows three spectral *** first system displays at most one temporal maximum and no beats in ultrafast temporal,whereas the second system may have three temporal maxima and two beats due to a combination of broken symmetry and the coherent superposition between various plasmon modes induced by the ultra-short laser ***,the shape of temporal dynamics of the size-asymmetric dimer is significantly deformed due to the excitation of local plasmon modes with different wavelength ***,the decay time of the amplitude of the local field is longer and oscillates with a high frequency due to the narrower linewidth and red-shifted spectral *** show that the ultrafast plasmon responses of both dimers can be controlled by varying the relative phase and time delays between a pair of two *** results will open new paths to understanding ultrafast plasmon responses in asymmetric heterodimers with suitable properties for different applications.

关键词： ultrafast plasmon dynamics coherent control spectral intensity temporal maximum

基于工业互联网的电梯动态数据采集系统的研究与应用

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自动化与仪器仪表 2024年第3期 131-134页

作者：胡光雄廖志强吴翩卉林景全广东交通职业技术学院机电工程学院广州510800 广东省特种设备检测研究院梅州检测院广东梅州514072 广东技术师范大学机电学院广州510665 广东铃木电梯有限公司电气研发部广东佛山528216

针对电梯运行过程存在因故障可能导致困人等严重事故的问题,设计基于工业互联网的电梯动态数据采集系统,以实现电梯动态数据的精准采集和电梯困人结果的远程监测和分析。加装的智能传感器以第三方的形式实时采集电梯的各路运行数据并通... 详细信息

针对电梯运行过程存在因故障可能导致困人等严重事故的问题,设计基于工业互联网的电梯动态数据采集系统,以实现电梯动态数据的精准采集和电梯困人结果的远程监测和分析。加装的智能传感器以第三方的形式实时采集电梯的各路运行数据并通过4 G或5 G网关传输到互联网云端服务器,利用现场总线和运营商无线通信网络实现人、机、系统的信息交互,完成对现场电梯的动态运行数据的监测;云端服务器上的监控组态决策分析系统根据智能化困人算法进行分析和决策,并通过应用接口向电梯维保系统推送困人指令,实现电梯困人结果的远程监测和分析。该系统在某市的试点应用结果表明:系统运行稳定,使用效果良好,系统达到了预定的设计目标。

关键词：工业互联网动态数据电梯困人远程监测

Theory of multiphoton photoemission disclosing excited states in conduction band of individual TiO_(2) nanoparticles

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Chinese Physics B 2021年第11期30卷 69-75页

作者： Bochao Li Hao Li Chang Yang Boyu Ji jingquan lin Toshihisa Tomie School of Science Changchun University of Science and TechnologyChangchun 130022China

A theory of multiphoton photoemission is derived to explain the experimentally observed monotonic decrease with the wavelength in the electron yield of TiO_(2) nanoparticles(NPs)by as large as four orders of *** is found that the fitting parameter corresponds to the energy position of Ti3d e_(g) and t_(2g) states,and the derived theory is a novel diagnostic of excited states in the conduction band,very importantly,applicable to individual *** difference between four-photon slope NPs and three-photon slope NPs is attributed to the difference in defect *** success of the theory in solving the puzzling result shows that thermal emission from high-lying levels may dominate over direct multiphoton ionization in solids when the photon number larger than four is required.

关键词： multiphoton photoemission nanoparticles thermal emission TiO_(2)

Ultrafast spatiotemporal control of directional launching of surface plasmon polaritons in a plasmonic nano coupler

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Photonics Research 2021年第4期9卷 514-520页

作者： Yulu Qin Boyu Ji Xiaowei Song jingquan lin Department of Physics Changchun University of Science and TechnologyChangchun 130022China

Ultrafast spatiotemporal control of a surface plasmon polariton(SPP)launch direction is a prerequisite for ultrafast information processing in plasmonic nanocircuit components such as ultrafast on–off of plasmonic switching and information *** we realize for the first time,to the best of our knowledge,ultrafast spatiotemporal control of the preferential launch direction of an SPP at the nano-femtosecond scale via a plasmonic nano directional *** spatiotemporal switching of the SPP field was revealed using time-resolved photoemission electron microscopy(TR-PEEM).Experimental results show that the extinction ratio of the SPP directional coupler can be substantially optimized by properly selecting the amplitude and time delay of the two incident light pulses in the *** importantly,we demonstrate a solution for the launch direction of the SPP field,switched in a plasmonic nano directional coupler on the femtosecond timescale,by adjusting the instantaneous polarization state of the excitation *** TR-PEEM images are supported by finite-difference time-domain(FDTD)*** believe the results of this study can be used to develop high-speed,miniaturized signal processing systems.

关键词： polarization switched directional

Disclosing transverse spin angular momentum of surface plasmon polaritons through independent spatiotemporal imaging of its in-plane and out-of-plane electric field components

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Photonics Research 2020年第6期8卷 1042-1048页

作者： YULU QIN BOYU JI XIAOWEI SONG jingquan lin Department of Physics Changchun University of Science and TechnologyChangchun 130022China

The comprehensive capture of near field spatiotemporal information of surface plasmon polaritons(SPPs)is a prerequisite for revealing their physical *** this study,we first performed an independent,spatiotemporal imaging of the out-of-plane and in-plane components of SPP near fields in a femtosecond light-excited trench using an obliquely incident time-resolved photoemission electron microscopy(TR-PEEM).We did the capture by imaging of the interference patterns induced by a superposition of the p-or s-polarized probe light,with the out-plane or in-plane components of SPP near-fields,under the noncollinear excitation *** method may be used to reconstruct a 3D SPP spatiotemporal ***,we demonstrated that the fringe shift of the in-terference patterns between the captured in plane and out-of plane components of the SPP field in PEEM images corresponds to the 1/4 fringe period,which is attributed toπ/2 out of phase of the out-of plane and in-plane near-field components of *** resulting TR-PEEM images are supported by a classical wave mode and FDTD ***,the measuredπ/2 phase difference between the in-plane and out-of plane components of the SPP indicated a rotating field component in the propagation plane,i.e,that the SPP exhibits an elliptically polarized electric field in the propagation *** experimental results presented herein provide direct evidence of SPP having the inherent attributes of transverse spin angular momentum.

关键词： field. plane angular

Femtosecond laser micro-nano processing for boosting bubble releasing of gas evolution reactions

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Nano Research 2022年第2期15卷 1672-1679页

作者： Shuai Zhang Lishuang Xu Jie Wu Ying Yang Chengxin Zhang Haiyan Tao jingquan lin Licheng Huang Wencheng Fang Keying Shi Xiangting Dong Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province Changchun University of Science and TechnologyChangchun 130022China School of Science Changchun University of Science and TechnologyChangchun 130022China International Research Centre for Nano Handling and Manufacturing of China Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Material ScienceHeilongjiang UniversityHarbin 150080China

Coupling effect of chemical composition and physical structure is a key factor to construct superaerophobic *** all reports about superaerophobic electrodes were aimed at precisely controlling morphology of loaded materials(constructing specific structure)and ignored the due role of ***,in this work,by using high precision and controllable femtosecond laser,hierarchical micro-nano structures with superaerophobic properties were constructed on the surface of silicon substrate(fs-Si),and such special super-wettability could be successfully inherited to subsequent self-supporting electrodes through chemical *** laser processing endowed electrodes with high electrochemical surface area,strong physical structure,and remarkable superaerophobic *** an unconventional processing method,the reconstructed morphology of substrate surface bears the responsibility of superaerophobicity,thus liberating the structural constraints on loaded *** this key of coupling effect is transferred from the loaded materials to substrate,we provided a new general scheme for synthesizing superaerophobic *** successful introduction of femtosecond laser will open a new idea to synthesize self-supporting electrodes for gas-involving reactions.

关键词： femtosecond laser gas evolution reactions hydrogen evolution reaction superaerophobic electrodes bubbles releasing