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Comparison of gene expression profiles between primary tumor and metastatic lesions in gastric cancer patients using laser microdissection and cDNA microarray 被引量:8
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作者 Long Wang Jin-Shui Zhu +2 位作者 Ming-Quan Song Guo-Qiang Chen Jin-Lian Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第43期6949-6954,共6页
AIM: To study the differential gene expression profiles of target cells in primary gastric cancer and its metastatic lymph nodes using laser microdissection (LMD) in combi- nation with cDNA microarray. METHODS: Normal... AIM: To study the differential gene expression profiles of target cells in primary gastric cancer and its metastatic lymph nodes using laser microdissection (LMD) in combi- nation with cDNA microarray. METHODS: Normal gastric tissue samples from 30 healthy individuals, 36 cancer tissue samples from pri- mary gastric carcinoma and lymph node metastasis tissue samples from 58 patients during gastric cancer resection were obtained using LMD in combination with cDNA microarray independently. After P27-based am- plification, aRNA from 36 of 58 patients (group 1) with lymph node metastasis and metastatic tissue specimens from the remaining 22 patients (group 2) were applied to cDNA microarray. Semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) and immunohisto- chemical assay verified the results of microarray in group 2 and further identified genes differentially expressed in the progression of gastric cancer. RESULTS: The expression of 10 genes was up-regulated while the expression of 15 genes was down-regulated in 22 gastric carcinoma samples compared with that of genes in the normal controls. The results were confirmed at the level of mRNA and protein, and suggested that four genes (OPCML, RNASE1, YES1 and ACK1) could play a key role in the tumorigenesis and metastasis of gastric cancer. The expression pattern of 3 genes (OPCML, RNASE1 and YES1) was similar to tumor suppressor genes. For example, the expression level of these genes was the highest in normal gastric epithelium, which was decreased in primary carcinoma, and further decreased in metastatic lymph nodes. On the contrary, the expres-sion pattern of gene ACK1 was similar to that of onco- gene. Four genes were further identified as differentially expressed genes in the majority of the cases in the pro- gression of gastric cancer. CONCLUSION: LMD in combination with cDNA microar- ray provides a unique support foe the identification of early expression profiles of differential genes and the ex- pression pattern of 3 genes (OPCML, RNASE1 and YES1) associated with the progression of gastric cancer. Further study is needed to reveal the molecular mechanism of lymph node metastasis in patients with gastric cancer. 展开更多
关键词 基因表达 原发肿瘤 胃癌 显微检查
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Gene profiles between non-invasive and invasive colon cancer using laser microdissection and polypeptide analysis 被引量:2
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作者 Jin-Shui Zhu Hua Guo +3 位作者 Ming-Quan Song Guo-Qiang Chen Qun Sun Qiang Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第38期5887-5892,共6页
AIM: To explore the expression of differential gene expression profiles of target cell between non-invasive submucosal and invasive advanced tumor in colon carcinoma using laser microdissection (LMD) in combination wi... AIM: To explore the expression of differential gene expression profiles of target cell between non-invasive submucosal and invasive advanced tumor in colon carcinoma using laser microdissection (LMD) in combination with polypeptide analysis. METHODS: Normal colon tissue samples from 20 healthy individuals and 30 cancer tissue samples from early non-invasive colon cancer cells were obtained. The cells from these samples were used LMD independently after P27-based amplification. aRNA from advanced colon cancer cells and metastatic cancer cells of 40 cases were applied to LMD and polypeptide analysis, semiquantitative reverse transcribed polymerase chain reaction (RT-PCR) and immunohistochemical assays were used to verify the results of microarray and further identify differentially expressed genes in non-invasive early stages of colon cancer. RESULTS: Five gene expressions were changed in colon carcinoma cells compared with that of controls. Of the five genes, three genes were downregulated and two were upregulated in invasive submucosal colon carcinoma compared with non-invasive cases. The results were confirmed at the level of aRNA and gene expression. Five genes were further identified as differentially expressed genes in the majority ofcases (> 50%, 25/40) in progression of colon cancer, and their expression patterns of which were similar to tumor suppressor genes or oncogenes. CONCLUSION: This study suggested that combined use of polypeptide analysis might identify early expression profiles of five differential genes associated with the invasion of colon cancer. These results reveal that this gene may be a marker of submucosal invasion in early colon cancer. 展开更多
关键词 结肠癌 激光微解剖 多肽分析 基因分析
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Quantitative analysis of RNA levels from single hepatocytes in vivo: combined use of real-time RT-PCR and laser microdissection
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作者 SHI Xin Jǒg Kleeff +5 位作者 ZHU Zhao - wen Bruno Schmied TANG Wen - hao Arthur Zimmermann Markus W. Bǔchle Helmut Friess 《中国病理生理杂志》 CAS CSCD 北大核心 2007年第11期2285-2288,共4页
AIM: The manner in which a cell responds to and influences its environment is ultimately determined by the genes that are expressed. To better understand cellular functions, the isolation of single cells and subsequen... AIM: The manner in which a cell responds to and influences its environment is ultimately determined by the genes that are expressed. To better understand cellular functions, the isolation of single cells and subsequent quantification of the expressed genes is essential. METHODS: Normal liver tissue was obtained from operation, snap-frozen in liquid nitrogen and sectioned in crystat. Individual hepatocytes were microdissected. RNA was extracted, then reverse transcribed and amplified using real-time quantitative polymerase chain reaction (PCR). RESULTS: Single hepatocytes were dissected by laser beam and catapulted to the microcentrifuge cap which was put above the slide. In this way, cells were collected, RNA was extracted, reverse transcribed to cDNA and used for analysis of RNA expression by real-time quantitative PCR. The amplification results showed that quantitation of the RNA inside the cell was compatible with the number of cells. CONCLUSION: The expression of RNA in single cells can be quantitated successfully by using laser microdissection and real-time PCR. These techniques provide an opportunity to monitor in vivo gene expression levels in single hepatocytes. 展开更多
关键词 RNA 肝细胞 实时RT-PCR 激光显微切割 数量性状
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Transcriptional regulatory network during axonal regeneration of dorsal root ganglion neurons:laser-capture microdissection and deep sequencing
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作者 Li-Li Zhao Tao Zhang +2 位作者 Wei-Xiao Huang Ting-Ting Guo Xiao-Song Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第9期2056-2066,共11页
The key regulators and regeneration-associated genes involved in axonal regeneration of neurons after injury have not been clarified.In high-throughput sequencing,various factors influence the final sequencing results... The key regulators and regeneration-associated genes involved in axonal regeneration of neurons after injury have not been clarified.In high-throughput sequencing,various factors influence the final sequencing results,including the number and size of cells,the depth of sequencing,and the method of cell separation.There is still a lack of research on the detailed molecular expression profile during the regeneration of dorsal root ganglion neuron axon.In this study,we performed lase r-capture microdissection coupled with RNA sequencing on dorsal root ganglion neurons at 0,3,6,and 12 hours and 1,3,and 7 days after sciatic nerve crush in rats.We identified three stages after dorsal root ganglion injury:early(3-12 hours),pre-regeneration(1 day),and regeneration(3-7 days).Gene expression patterns and related function enrichment res ults showed that one module of genes was highly related to axonal regeneration.We verified the up-regulation of activating transcription factor 3(Atf3),Kruppel like factor 6(Klf6),AT-rich inte raction domain 5A(Arid5α),CAMP responsive element modulator(Crem),and FOS like 1,AP-1 transcription factor Subunit(Fosl1) in dorsal root ganglion neurons after injury.Suppressing these transcription factors(Crem,Arid5o,Fosl1 and Klf6) reduced axonal regrowth in vitro.As the hub transcription factor,Atf3 showed higher expression and activity at the preregeneration and regeneration stages.G protein-coupled estrogen receptor 1(Gper1),inte rleukin 12a(Il12α),estrogen receptor 1(ESR1),and interleukin 6(IL6) may be upstream factors that trigger the activation of Atf3 during the repair of axon injury in the early stage.Our study presents the detailed molecular expression profile during axonal regeneration of dorsal root ganglion neurons after peripheral nerve injury.These findings may provide reference for the clinical screening of molecular targets for the treatment of peripheral nerve injury. 展开更多
关键词 Arid5a ATF3 Crem dorsal root ganglion Fosl1 KLF6 laser-capture microdissection NEURON smart-seq2 gene expression profile transcription factor
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Vulnerability assessment of UAV engine to laser based on improved shotline method
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作者 Le Liu Chengyang Xu +3 位作者 Changbin Zheng Sheng Cai Chunrui Wang Jin Guo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期588-600,共13页
Laser anti-drone technology is entering the sequence of actual combat,and it is necessary to consider the vulnerability of typical functional parts of UAVs.Since the concept of"vulnerability"was proposed,a v... Laser anti-drone technology is entering the sequence of actual combat,and it is necessary to consider the vulnerability of typical functional parts of UAVs.Since the concept of"vulnerability"was proposed,a variety of analysis programs for battlefield targets to traditional weapons have been developed,but a comprehensive assessment methodology for targets'vulnerability to laser is still missing.Based on the shotline method,this paper proposes a method that equates laser beam to shotline array,an efficient vulnerability analysis program of target to laser is established by this method,and the program includes the circuit board and the wire into the vulnerability analysis category,which improves the precision of the vulnerability analysis.Taking the UAV engine part as the target of vulnerability analysis,combine with the"life-death unit method"to calculate the laser penetration rate of various materials of the UAV,and the influence of laser weapon system parameters and striking orientation on the killing probability is quantified after introducing the penetration rate into the vulnerability analysis program.The quantitative analysis method proposed in this paper has certain general expansibility,which can provide a fresh idea for the vulnerability analysis of other targets to laser. 展开更多
关键词 laser weapon laser damage VULNERABILITY UAV ENGINE Killing probability
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An LED-Side-Pumped Intracavity Frequency-Doubled Nd,Ce:YAG Laser Producing a 2W Q-Switched Red Beam
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作者 沈建平 徐少聪 +6 位作者 芦鹏 江容容 王巍 张四维 邢凤阳 陈阳 陈亮 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期44-47,共4页
We report a high-average-power acousto-optic(AO)Q-switched intracavity frequency-doubled red laser based on a high-efficiency light-emitting-diode(LED)pumped two-rod Nd,Ce:YAG laser module.Under quasi-continuous wave ... We report a high-average-power acousto-optic(AO)Q-switched intracavity frequency-doubled red laser based on a high-efficiency light-emitting-diode(LED)pumped two-rod Nd,Ce:YAG laser module.Under quasi-continuous wave operation conditions,a maximum output power of 1319.08 nm wavelength was achieved at 11.26 W at a repetition rate of 100 Hz. 展开更多
关键词 PUMPED SWITCHED laser
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GaN based ultraviolet laser diodes
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作者 Jing Yang Degang Zhao +9 位作者 Zongshun Liu Yujie Huang Baibin Wang Xiaowei Wang Yuheng Zhang Zhenzhuo Zhang Feng Liang Lihong Duan Hai Wang Yongsheng Shi 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期6-15,共10页
In the past few years,many groups have focused on the research and development of GaN-based ultraviolet laser diodes(UV LDs).Great progresses have been achieved even though many challenges exist.In this article,we ana... In the past few years,many groups have focused on the research and development of GaN-based ultraviolet laser diodes(UV LDs).Great progresses have been achieved even though many challenges exist.In this article,we analyze the challenges of developing GaN-based ultraviolet laser diodes,and the approaches to improve the performance of ultraviolet laser diode are reviewed.With these techniques,room temperature(RT)pulsed oscillation of AlGaN UVA(ultraviolet A)LD has been realized,with a lasing wavelength of 357.9 nm.Combining with the suppression of thermal effect,the high output power of 3.8 W UV LD with a lasing wavelength of 386.5 nm was also fabricated. 展开更多
关键词 DIODES laser GAN
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975 nm multimode semiconductor lasers with high-order Bragg diffraction gratings
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作者 Zhenwu Liu Li Zhong +1 位作者 Suping Liu Xiaoyu Ma 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期38-44,共7页
The 975 nm multimode diode lasers with high-order surface Bragg diffraction gratings have been simulated and calcu-lated using the 2D finite difference time domain(FDTD)algorithm and the scattering matrix method(SMM).... The 975 nm multimode diode lasers with high-order surface Bragg diffraction gratings have been simulated and calcu-lated using the 2D finite difference time domain(FDTD)algorithm and the scattering matrix method(SMM).The periods and etch depth of the grating parameters have been optimized.A board area laser diode(BA-LD)with high-order diffraction grat-ings has been designed and fabricated.At output powers up to 10.5 W,the measured spectral width of full width at half maxi-mum(FWHM)is less than 0.5 nm.The results demonstrate that the designed high-order surface gratings can effectively nar-row the spectral width of multimode semiconductor lasers at high output power. 展开更多
关键词 laser diodes distributed Bragg reflector high order gratings high power laser diodes narrow spectrum width
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Broadband bidirectional Brillouin–Raman random fiber laser with ultra-narrow linewidth
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作者 杨茜 李阳 +3 位作者 邹辉 梅杰 徐恩明 张祖兴 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期371-376,共6页
We present a Brillouin–Raman random fiber laser(BRRFL)with full-open linear cavity structure to generate broadband Brillouin frequency comb(BFC)with double Brillouin-frequency-shift spacing.The incorporation of a reg... We present a Brillouin–Raman random fiber laser(BRRFL)with full-open linear cavity structure to generate broadband Brillouin frequency comb(BFC)with double Brillouin-frequency-shift spacing.The incorporation of a regeneration portion consisting of an erbium-doped fiber and a single-mode fiber enables the generation of broadband BFC.The dynamics of broadband BFC generation changing with the pump power(EDF and Raman)and Brillouin pump(BP)wavelength are investigated in detail,respectively.Under suitable conditions,the bidirectional BRRFL proposed can produce a flatamplitude BFC with 40.7-nm bandwidth ranging from 1531 nm to 1571.7 nm,and built-in 242-order Brillouin Stokes lines(BSLs)with double Brillouin-frequency-shift spacing.Moreover,the linewidth of single BSL is experimentally measured to be about 2.5 kHz.The broadband bidirectional narrow-linewidth BRRFL has great potential applications in optical communication,optical sensing,spectral measurement,and so on. 展开更多
关键词 random laser fiber laser stimulated Brillouin scattering(SBS) stimulated Raman scattering(SRS)
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Nonstationary laser-supported ionization wave in layer of porous substance with subcritical density
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作者 S.Yu Gus’kov R.A.Yakhin 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第1期58-70,共13页
A time-dependent analytical solution is found for the velocity of a plane ionization wave generated under nanosecond laser pulse action on the surface of a flat layer of low-Z porous substance with density less than t... A time-dependent analytical solution is found for the velocity of a plane ionization wave generated under nanosecond laser pulse action on the surface of a flat layer of low-Z porous substance with density less than the critical density of the produced plasma.With corrections for the two-dimensional nature of the problem when a laser beam of finite radius interacts with a flat target,this solution is in quantitative agreement with measurements of ionization wave velocity in various experiments.The solution compared with experimental data covering wide ranges of performance conditions,namely,(3-8)×10^(14)W cm^(−2)for laser pulse intensity,0.3-3 ns for pulse duration,0.35-0.53μm for laser wavelength,100-1000μm for laser beam radius,380-950μm for layer thickness,4.5-12 mg cm^(−3)for average density of porous substance,and 1-25μm for average pore size.The parameters of the laser beam that ensure the generation of a plane ionization wave in a layer of subcritical porous matter are determined for the problem statements and are found to meet the requirements of practical applications. 展开更多
关键词 laser PULSE POROUS
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Backward scattering of laser plasma interactions from hundreds-of-joules broadband laser on thick target
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作者 Peipei Wang Honghai An +14 位作者 Zhiheng Fang Jun Xiong Zhiyong Xie Chen Wang Zhiyu He Guo Jia Ruirong Wang Shu Zheng Lan Xia Wei Feng Haitao Shi Wei Wang Jinren Sun Yanqi Gao Sizu Fu 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第1期5-14,共10页
The use of broadband laser technology is a novel approach for inhibiting processes related to laser plasma interactions(LPIs).In this study,several preliminary experiments into broadband-laser-driven LPIs are carried ... The use of broadband laser technology is a novel approach for inhibiting processes related to laser plasma interactions(LPIs).In this study,several preliminary experiments into broadband-laser-driven LPIs are carried out using a newly established hundreds-of-joules broadband second-harmonic-generation laser facility.Through direct comparison with LPI results for a traditional narrowband laser,the actual LPI-suppression effect of the broadband laser is shown.The broadband laser had a clear suppressive effect on both back-stimulated Raman scattering and back-stimulated Brillouin scattering at laser intensities below 1×10^(15) W cm^(−2).An abnormal hot-electron phenomenon is also investigated,using targets of different thicknesses. 展开更多
关键词 SCATTERING laser hundreds
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Heating of nanoparticles and their environment by laser radiation and applications
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作者 Victor K.Pustovalov 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期78-115,共38页
This review considers the fundamental dynamic processes involved in the laser heating of metal nanoparticles and their subsequent cooling.Of particular interest are the absorption of laser energy by nanoparticles,the ... This review considers the fundamental dynamic processes involved in the laser heating of metal nanoparticles and their subsequent cooling.Of particular interest are the absorption of laser energy by nanoparticles,the heating of a single nanoparticle or an ensemble thereof,and the dissipation of the energy of nanoparticles due to heat exchange with the environment.The goal is to consider the dependences and values of the temperatures of the nanoparticles and the environment,their time scales,and other parameters that describe these processes.Experimental results and analytical studies on the heating of single metal nanoparticles by laser pulses are discussed,including the laser thresholds for initiating subsequent photothermal processes,how temperature influences the optical properties,and the heating of gold nanoparticles by laser pulses.Experimental studies of the heating of an ensemble of nanoparticles and the results of an analytical study of the heating of an ensemble of nanoparticles and the environment by laser radiation are considered.Nanothermometry methods for nanoparticles under laser heating are considered,including changes in the refractive indices of metals and spectral thermometry of optical scattering of nanoparticles,Raman spectroscopy,the thermal distortion of the refractive index of an environment heated by a nanoparticle,and thermochemical phase transitions in lipid bilayers surrounding a heated nanoparticle.Understanding the sequence of events after radiation absorption and their time scales underlies many applications of nanoparticles.The applicationfields for the laser heating of nanoparticles are reviewed,including thermochemical reactions and selective nanophotothermolysis initiated in the environment by laser-heated nanoparticles,thermal radiation emission by nanoparticles and laser-induced incandescence,electron and ion emission of heated nanoparticles,and optothermal chemical catalysis.Applications of the laser heating of nanoparticles in laser nanomedicine are of particular interest.Significant emphasis is given to the proposed analytical approaches to modeling and calculating the heating processes under the action of a laser pulse on metal nanoparticles,taking into account the temperature dependences of the parameters.The proposed models can be used to estimate the parameters of lasers and nanoparticles in the various applicationfields for the laser heating of nanoparticles. 展开更多
关键词 NANOPARTICLES laser HEATING MODELING Nanothermometry Applications
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On the generation of high-quality Nyquist pulses in mode-locked fiber lasers
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作者 任俞宣 葛锦蔓 +2 位作者 李小军 彭俊松 曾和平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期424-427,共4页
Nyquist pulses have wide applications in many areas,from electronics to optics.Mode-locked lasers are ideal platforms to generate such pulses.However,how to generate high-quality Nyquist pulses in mode-locked lasers r... Nyquist pulses have wide applications in many areas,from electronics to optics.Mode-locked lasers are ideal platforms to generate such pulses.However,how to generate high-quality Nyquist pulses in mode-locked lasers remains elusive.We address this problem by managing different physical effects in mode-locked fiber lasers through extensive numerical simulations.We find that net dispersion,linear loss,gain and filter shaping can affect the quality of Nyquist pulses significantly.We also demonstrate that Nyquist pulses experience similariton shaping due to the nonlinear attractor effect in the gain medium.Our work may contribute to the design of Nyquist pulse sources and enrich the understanding of pulse shaping dynamics in mode-locked lasers. 展开更多
关键词 mode locking laser SOLITON FIBER PULSE
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Polarization control of above-threshold ionization spectrum in elliptically polarized two-color laser fields
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作者 金发成 杨慧慧 +8 位作者 宋晓红 李飞 杜玲玲 薛红杰 魏丽敏 白悦 刘浩翔 王兵兵 杨玮枫 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期136-144,共9页
We study the above-threshold ionization(ATI)process of atoms exposed to fundamental and high-frequency lasers with arbitrary ellipticity by applying the frequency-domain theory.It is found that the angular-resolved AT... We study the above-threshold ionization(ATI)process of atoms exposed to fundamental and high-frequency lasers with arbitrary ellipticity by applying the frequency-domain theory.It is found that the angular-resolved ATI spectrum is sensitive to ellipticities of two lasers and emitted angles of the photoelectron.Particularly for the photon energy of the highfrequency laser more than atomic ionization potential,the width of plateau tends to a constant with increasing ellipticity of fundamental field,the dip structure disappears with increasing ellipticity of the high-frequency field.With the help of the quantum channel analysis,it is shown that the angular distribution depends mainly on the ellipticity of high-frequency field in the case that its frequency is high.Moreover,one can see that the maximal and minimal energies in quantum numerical results are in good agreement with the classical prediction.Our investigation may provide theoretical support for experimental research on polarization control of ionization in elliptically polarized two-color laser fields. 展开更多
关键词 above-threshold ionization two-color laser polarization control
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A comprehensive review on the processing-property relationships of laser strengthened magnesium
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作者 Alessandro M.Ralls Aaksheta Agnel Pradeep L.Menezes 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期1-34,共34页
Among the existing series of softer metals,magnesium(Mg)has attracted much attention due to its impressive strength-to-weight ratio.However,due to its ease of deformability,Mg tends to suffer from rapid degradation in... Among the existing series of softer metals,magnesium(Mg)has attracted much attention due to its impressive strength-to-weight ratio.However,due to its ease of deformability,Mg tends to suffer from rapid degradation in a wide variety of abrasive and electrochemical environments.One method of improving its surface properties is through surface modification techniques.Among the existing techniques,laser shock peening(LSP)has been one of the most widely utilized processes due to its surface-hardening-like effects.Despite this understanding,a comprehensive review has yet to exist that encapsulates the strengthening mechanism of LSP for Mg and its influence in degradation environments.This review aims to encapsulate the existing research around the LSP field for Mg.Specifically,an understanding of the surface-strengthening effects in relation to its mechanical,tribological,corrosion,and tribo-corrosion characteristics is elucidated.Additionally,the feasibility of LSP for Mg materials in critical industries is also discussed.Through this work,a novel understanding of LSP for Mg can be understood,which can provide a future direction for research in this field. 展开更多
关键词 laser shock peening MAGNESIUM Surface deformation TRIBOLOGY Microstructure
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Laser‑Induced and MOF‑Derived Metal Oxide/Carbon Composite for Synergistically Improved Ethanol Sensing at Room temperature
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作者 Hyeongtae Lim Hyeokjin Kwon +2 位作者 Hongki Kang Jae Eun Jang Hyuk‑Jun Kwon 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期210-220,共11页
Advancements in sensor technology have significantly enhanced atmospheric monitoring.Notably,metal oxide and carbon(MO_(x)/C)hybrids have gained attention for their exceptional sensitivity and room-temperature sensing... Advancements in sensor technology have significantly enhanced atmospheric monitoring.Notably,metal oxide and carbon(MO_(x)/C)hybrids have gained attention for their exceptional sensitivity and room-temperature sensing performance.However,previous methods of synthesizing MO_(x)/C composites suffer from problems,including inhomogeneity,aggregation,and challenges in micropatterning.Herein,we introduce a refined method that employs a metal–organic framework(MOF)as a precursor combined with direct laser writing.The inherent structure of MOFs ensures a uniform distribution of metal ions and organic linkers,yielding homogeneous MO_(x)/C structures.The laser processing facilitates precise micropatterning(<2μm,comparable to typical photolithography)of the MO_(x)/C crystals.The optimized MOF-derived MO_(x)/C sensor rapidly detected ethanol gas even at room temperature(105 and 18 s for response and recovery,respectively),with a broad range of sensing performance from 170 to 3,400 ppm and a high response value of up to 3,500%.Additionally,this sensor exhibited enhanced stability and thermal resilience compared to previous MOF-based counterparts.This research opens up promising avenues for practical applications in MOF-derived sensing devices. 展开更多
关键词 Metal-organic frameworks Metal oxide Carbon composite laser Gas sensor
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Effect of sample temperature on femtosecond laser ablation of copper
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作者 党伟杰 陈雨桐 +1 位作者 陈安民 金明星 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期377-385,共9页
We conduct an experimental study supported by theoretical analysis of single laser ablating copper to investigate the interactions between laser and material at different sample temperatures,and predict the changes of... We conduct an experimental study supported by theoretical analysis of single laser ablating copper to investigate the interactions between laser and material at different sample temperatures,and predict the changes of ablation morphology and lattice temperature.For investigating the effect of sample temperature on femtosecond laser processing,we conduct experiments on and simulate the thermal behavior of femtosecond laser irradiating copper by using a two-temperature model.The simulation results show that both electron peak temperature and the relaxation time needed to reach equilibrium increase as initial sample temperature rises.When the sample temperature rises from 300 K to 600 K,the maximum lattice temperature of the copper surface increases by about 6500 K under femtosecond laser irradiation,and the ablation depth increases by 20%.The simulated ablation depths follow the same general trend as the experimental values.This work provides some theoretical basis and technical support for developing femtosecond laser processing in the field of metal materials. 展开更多
关键词 femtosecond laser two-temperature model sample temperature ablation depth
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Gigahertz frequency hopping in an optical phase-locked loop for Raman lasers
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作者 毛德凯 税鸿冕 +3 位作者 殷国玲 彭鹏 王春唯 周小计 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期60-65,共6页
Raman lasers are essential in atomic physics,and the development of portable devices has posed requirements for time-division multiplexing of Raman lasers.We demonstrate an innovative gigahertz frequency hopping appro... Raman lasers are essential in atomic physics,and the development of portable devices has posed requirements for time-division multiplexing of Raman lasers.We demonstrate an innovative gigahertz frequency hopping approach of a slave Raman laser within an optical phase-locked loop(OPLL),which finds practical application in an atomic gravimeter,where the OPLL frequently switches between near-resonance lasers and significantly detuned Raman lasers.The method merges the advantages of rapid and extensive frequency hopping with the OPLL’s inherent low phase noise,and exhibits a versatile range of applications in compact laser systems,promising advancements in portable instruments. 展开更多
关键词 Raman lasers optical phase-locked loop frequency hopping
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Residual stress modeling of mitigated fused silica damage sites with CO_(2)laser annealing
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作者 张传超 廖威 +3 位作者 张丽娟 蒋晓龙 方振华 蒋晓东 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期509-514,共6页
A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage sites.The proposed model extracts the resi... A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage sites.The proposed model extracts the residual strain from the differences in thermoelastic contraction of fused silica with different fictive temperatures from the initial frozen-in temperatures to ambient temperature.The residual stress fields of mitigated damage sites for the CO_(2)laser-annealed case are obtained by a finite element analysis of equilibrium equations and constitutive equations.The simulated results indicate that the proposed model can accurately evaluate the residual stress fields of laser-annealed mitigated damage sites with a complex thermal history.The calculated maximum hoop stress is in good agreement with the reported experimental result.The estimated optical retardance profiles from the calculated radial and hoop stress fields are consistent with the photoelastic measurements.These results provide sufficient evidence to demonstrate the suitability of the proposed model for describing the residual stresses of mitigated fused silica damage sites after CO_(2)laser annealing. 展开更多
关键词 fused silica damage mitigation residual stress laser annealing
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