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Air-Laser-Based Standoff Coherent Raman Spectrometer

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Ultrafast Science 2022年第4期2卷 21-29页

作者： Yao Fu Jincheng Cao Kaoru Yamanouchi huailiang xu State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China Department of Chemistry School of ScienceThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-0033Japa CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800China

Among currently available optical spectroscopic methods,Raman spectroscopy has versatile application to investigation of dynamical processes of molecules leading to chemical changes in the gas and liquid ***,it is still a challenge to realize an ideal standoff coherent Raman spectrometer with which both high temporal resolution and high-frequency resolution can be achieved,so that one can remotely probe chemical species in real time with high temporal resolution while monitoring the populations in their respective rovibronic levels in the frequency domain with sufficiently high spectral *** the present study,we construct an air-laser-based Raman spectrometer,in which near-infrared femtosecond(fs)laser pulses at 800nm and cavity-free picosecond N,air-laser pulses at 391nm generated by the filamentation induced by the fs laser pulses are simultaneously used,enabling us to generate a hybrid ps/fs laser source at a desired standoff position for standoff surveillance of chemical and biochemical *** this prototype Raman spectrometer,we demonstrate that the temporal evolution of the electronic,vibrational,and rotational states of N and the coupling processes of the rovibrational wavepacketof N,molecules canbeprobed.

关键词： resolution versatile cavity

Goldilocks focal zone in femtosecond laser ignition of lean fuels

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Science China(Technological Sciences) 2022年第7期65卷 1537-1544页

作者： ZANG HongWei LI HeLong LIANG TianFeng CHEN ShanMing ZHANG Wei FU Yao xu huailiang LI RuXin State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800China State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsCASShanghai 201800China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China

Laser ignition of lean fuels offers a promising route for green combustion with high combustion efficiency and low exhaust emissions. The fundamental limitations which apply to femtosecond laser ignition(fs-LI) of lean fuels are the inferior energy deposition and low thermodynamic temperature. However, it was discovered recently that the fs laser filamentation can induce 100% success rate of fs-LI with ultralow sub-m J minimum ignition energy, exhibiting distinct contrast to the general understanding that it is hard to achieve fs-LI. The present contribution examines the extent to which the minimum ignition energies depend on filamentation formation, and explores the key factors for the success of fs-LI. We perform fs-LI of a lean-fuel CH;/air mixture using a femtosecond near-infrared(~40 fs, 800 nm) pulse at different external focal conditions, and find a Goldilocks focal zone to facilitate fs-LI. In this special zone, a crucial balance between the length of igniting “line” kernel and the plasma density of the fs laser filament is achieved, which determines not only the total amount of resultant OH radicals, but also their distribution along the plasma filament. Our finding provides a viable strategy with clear guidelines for fs-LI, and also opens up an avenue of exploring unprecedented ultrafast ignition dynamics after fs-laser-fuel interactions towards gaining deeper insights into reaction intermediates and combustion processes.

关键词： femtosecond laser laser ignition lean fuels laser filament laser spectroscopy

Femtosecond laser 3D fabrication of whispering-gallerymode microcavities

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Science China(Physics,Mechanics & Astronomy) 2015年第11期58卷 2-10页

作者： xu huailiang SUN HongBo State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University

Whispering-gallery-mode(WGM) microcavities with high-quality factors and small volumes have attracted intense interests in the past decades because of their potential applications in various research fields such as quantum information, sensing, and optoelectronics. This leads to rapid advance in a variety of processing technologies that can create high-quality WGM micro-cavities. Due to the unique characteristics of femtosecond laser pulses with high peak intensity and ultrashort pulse duration, femtosecond laser shows the ability to carry out ultrahigh precision micromachining of a variety of transparent materials through nonlinear multiphoton absorption and tunneling ionization. This review paper describes the basic principle of femtosecond laser direct writing, and presents an overview of recent progress concerning femtosecond laser three-dimensional(3D) fabrications of optical WGM microcavities, which include the advances in the fabrications of passive and active WGMs microcavities in a variety of materials such as polymer, glass and crystals, as well as in processing the integrated WGM-microcavity device. Lastly, a summary of this dynamic field with a future perspective is given.

关键词：科学学科学知识物理学力学天文学

Diet and feeding behavior of a group of high-altitude rhesus macaques: high adaptation to food shortages and seasonal fluctuations

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Current Zoology 2023年第3期69卷 304-314页

作者： Kechu Zhang Fazal Karim Zuxiang Jin Hongtao Xiao Yongfang Yao Qingyong Ni Bajin Li Wangjia Pu-Cuo Zhonghao Huang huailiang xu College of Life Science Sichuan Agricultural UniversityNo.46 Xinkang RoadYucheng DistrictYa'anSichuan 625014China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationNo.1Yanzhong RoadYanshan DistrictGuilingGuangxi 541006China College of Animal Science and Technology Sichuan Agricultural UniversityNo.211 Huimin RoadWenjiang DistrictChengduSichuan 611130China Gexigou National Nature Reserve Administration Yajiang Forestry and Grassland AdministrationNo.88 Jiefang RoadYajiang CountyGanziSichuan 627450China

Diet and feeding behavior data are crucial to a deep understanding of the behavioral response and adaptation of primates to a high-altitude *** August 2019 to June 2021,we collected data on the feeding behavior of a high-altitude rhesus macaque Macaca mulatta group from Yajiang County,Western Sichuan Plateau,which has an altitude of over 3,500 *** results showed that feeding(33.0±1.8%)and moving(28.3±2.6%)were the dominant behavior of rhesus *** ate 193 food items,comprising 11 food categories from 90 *** study found that plant roots(30.9±30.1%)and young leaves(28.0±33.1%)were the main foods eaten by *** preferred foods of rhesus macaques were young leaves,fruits,and seeds,and the consumption of these items was positively correlated with its food *** the availability of preferred foods was low,macaques took plant roots,barks,and fallen leaves as fallback *** particular,roots were a dominant food item in winter,and this way of feeding became a key survival *** results suggest that,facing the relative scarcity and strong seasonal fluctuations of food resources in high-altitude habitat,macaques adopt active foraging strategies,relying on a variety of food species and adjusting flexibly their food choices based on food availability,which may help to maximize the energy efficiency of high-altitude macaques.

关键词： diet foraging strategy fallback food high-altitude habitat Macaca mulatta

Femtosecond laser processing of microcavity lasers

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Frontiers of Optoelectronics 2016年第3期9卷 420-427页

作者： xuepeng ZHAN huailiang xu Hongbo SUN State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 China

In this paper, we reviewed the fabrications of functional microcavity lasers in soft materials such as polymer and protein by femtosecond laser processing. High-quality （Q） microdisks with a laser dye （Rhodamine B, RhB） acting as gain medium were fabricated that produced whispering-gallery-mode （WGM） lasing output. We also obtained unidirectional lasing output with a low lasing threshold in a deformed spiral microcavity at room temperature. Photonic-molecule （PM） microlasers were prepared to investigate the interaction and coupling effects of different cavities, and it was found that the distance between the two disks plays an important role in the lasing behaviors. Single-mode lasing was realized from a stacked PM microlaser through Vernier effect. Furthermore we adopted the biocompatible materials, RhB-doped proteins as a host material and fabricated a three-dimensional （3D） WGM microlaser, which operated well both in air and aqueous environment. The sensing of the protein micro- lasers to Na2SO4 concentration was investigated. Our results of fabricating high-Q microlasers with different materials reveal the potential applications of femtosecond laser processing in the areas of integrated optoelectronic and ultrahigh sensitive bio-sensing devices.

关键词： femtosecond laser processing microcavity lasers polymer protein

Multiple intron gain and loss events occurred during the evolution of Cenp-A gene

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Chinese Science Bulletin 2013年第17期58卷 2174-2178页

作者： FAN XinYu YU Li xu huailiang LI Ying College of Animal Science and Technology Sichuan Agricultural University Laboratory for Conservation and Utilization of Bio-resource Yunnan University Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province Yunnan University Institute of Animal Breeding and Genetics Sichuan Agricultural University

Centromere protein A(CENP-A) is a histone H3 like protein,and it plays a very important role in chromosomal segregation during mitosis and *** analyses on the exon-intron organization of the Cenp-A gene in representative genomes revealed that multiple intron gain and loss events have occurred during the evolution of Cenp-A gene in opisthokonta(common ancestor of fungi and animals).Moreover,our results revealed that at least two positions were conserved in the intron gain and loss events during the evolution of the Cenp-A gene.

关键词：进化过程基因组事件损失组蛋白H3 染色体分离分裂过程有丝分裂

Review:Coincidence Momentum Imaging:Principle and Application in Molecular Reaction Dynamics

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Journal of Harbin Institute of Technology(New Series) 2018年第4期25卷 1-14页

作者： Li Zhang huailiang xu Communications and Electronic Information Department Shanghai Vocational College of Science and Technology State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University

Coincidence Momentum Imaging(CMI) is a powerful imaging technique that can determine the full momentum vectors of all particles released from a single parent molecule in coincidence and thus provide detailed information on transient molecular *** far,the CMI technique has been extensively employed for investigating a variety of molecular reaction dynamics induced,e.g.,by particle collisions,intense laser fields and synchrotron *** this article,we first introduce the principle of the CMI technique,which is followed by several typical experimental designs of the CMI systems realizing the coincidence momentum *** then present representative examples of studying molecular reaction dynamics using the CMI technique.

关键词：动量成像动力学物理

Robust and ultralow-energy-threshold ignition of a lean mixture by an ultrashort-pulsed laser in the filamentation regime

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Light(Science & Applications) 2021年第3期10卷 320-326页

作者： Hongwei Zang Helong Li Wei Zhang Yao Fu Shanming Chen huailiang xu Ruxin Li State Key Laboratory of Integrated Optoelectronics College of ElectronicScience and EngineeringJilin University130012 ChangchunChina Instituteof Atomic and Molecular Physics Jilin University130012 ChangchunChina CAS Center for Excellence in Ultra-intense Laser Science 201800 ShanghaiChina State Key Laboratory of High Field Laser Physics Shanghai lnstitute of Optics and Fine MechanicsChinese Academy of Sciences201800 ShanghaChina School of Physical Science and Technology ShanghaiTech University201210 ShanghaiChina

Laser ignition(LI)allows for precise manipulation of ignition tinning and location and is promising for green combustion of automobile and rocket engines and aero-turbines under lean-fuel conditions with improved emission efficiency;however,achieving completely effective and reliable ignition is still a ***,we report the realization of igniting a lean methane/air mixture with a 100%success rate by an ultrashort femtosecond laser,which has long been regarded as an unsuitable fuel ignition *** demonstrate that the minimum ignition energy can decrease to the sub-mJ level depending on the laser filamentation formation,and reveal that the resultant early OH radical yield significantly increases as the laser energy reaches the ignition threshold,showing a clear boundary for misfire and fire *** mechanisms for robust ultrashort LI are the filamentation-induced heating effect followed by exothermal chemical reactions,in combination with the line ignition effect along the *** results pave the way toward robust and efficient ignition of lean-fuel engines by ultrashort-pulsed lasers.

关键词： ultrashort laser energy

Genetic differentiation and subspecies classification of rhesus macaques in the southeastern margin of the Qinghai-Tibetan Plateau

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Genetic differentiation and subspecies classification of rhe...