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长距离泵浦-探测系统的阿秒精度锁定

物理学报 2024年第19期73卷 31-36页

作者：王柯俭滕浩邢笑伟董朔曹凯强江昱佼赵昆朱江峰刘文军魏志义西安电子科技大学光电工程学院中国科学院物理研究所北京凝聚态物理国家实验室中国科学院大学物理科学学院松山湖材料实验室北京邮电大学理学院

随着超快科学和阿秒脉冲技术的发展,基于孤立阿秒脉冲的泵浦-探测系统由于能实现对电子动力学的时间分辨测量,已成为人们开展阿秒超快过程研究不可或缺的关键技术.但要获得稳定可靠的泵浦-探测信号,需要保证泵浦与探测光之间阿秒级的高... 详细信息

随着超快科学和阿秒脉冲技术的发展,基于孤立阿秒脉冲的泵浦-探测系统由于能实现对电子动力学的时间分辨测量,已成为人们开展阿秒超快过程研究不可或缺的关键技术.但要获得稳定可靠的泵浦-探测信号,需要保证泵浦与探测光之间阿秒级的高精度同步,较大的抖动将会导致信号产生弥散、甚至被淹埋在噪声中,从而无法获得真实的物理图像.由于阿秒脉冲从产生到应用终端之间的距离通常较长,要实现阿秒时间分辨,就必须对阿秒光脉冲与泵浦光进行阿秒量级的延时锁定.针对这一问题,本文发展了一种新型的双层光路系统,通过对获得的干涉条纹进行快速傅里叶变换,将获得的时间抖动量反馈给压电平移台实时补偿光程漂移,实现了泵浦光与探测光之间阿秒量级的同步锁定.应用该方案到光路长度从1—10 m的阿秒泵浦探测系统,得到了锁定精度分别从7.64—31.76 as的结果,分析表明系统延时误差与距离呈严格的线性关系,决定数R2=0.96.本研究工作表明,使用小型干涉仪可实现对大科学装置中长距离阿秒泵浦探测系统的锁定精度进行快速检测,这对如非共线阿秒条纹相机、时间分辨光电子能谱仪、相干合成等应用具有一定的参考意义.

关键词：超快科学泵浦探测系统延时锁定

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基于平凹多通腔的非线性脉冲压缩技术

物理学报 2024年第12期73卷 213-220页

作者：李聘滨滕浩田文龙黄振文朱江峰钟诗阳运晨霞刘文军魏志义西安电子科技大学光电工程学院西安710071 中国科学院物理研究所北京凝聚态物理国家研究中心北京100190 中国科学院大学物理学院北京100049 北京邮电大学理学院北京100876

采用平凹多通腔和固体薄片组的非线性脉冲光谱展宽与压缩方案开展了100 W皮秒激光非线性脉冲压缩的研究.以多片熔融石英薄片作为非线性介质,在平凹腔中皮秒激光通过自相位调制将光谱宽度由0.24 nm展宽4.8 nm,用光栅对进行色散补偿压缩,... 详细信息

采用平凹多通腔和固体薄片组的非线性脉冲光谱展宽与压缩方案开展了100 W皮秒激光非线性脉冲压缩的研究.以多片熔融石英薄片作为非线性介质,在平凹腔中皮秒激光通过自相位调制将光谱宽度由0.24 nm展宽4.8 nm,用光栅对进行色散补偿压缩,实现压缩后的脉冲宽度为483 fs,对应压缩比为22,最终输出飞秒激光的平均功率为44.2 W.相对于常规多通腔方案,该平凹腔结构紧凑,光路稳定性好,压缩比高,非常有利于非线性光谱展宽与压缩的实现.

关键词：多通腔自相位调制非线性脉冲压缩超快激光

An Octave-Spanning,Kerr-Lens Mode-Locked Ti:sapphire Oscillator with Double-Chirped Mirrors and BaF_(2)

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Chinese Physics Letters 2012年第11期29卷 88-90页

作者： ZHANG Long HAN Hai-Nian ZHANG Qing wei zhi-yi Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190

We demonstrate an octave-spanning Kerr-lens mode-locked Ti:sapphire laser with double-chirped mirrors(DCMs),BaF_(2) wedges and plate,which generates laser pulses in the spectrum range from 600 nm to 1200 nm at-45 dB below the maximum and the duration of 8.5 fs at the repetition rate of 80 *** average output power is 100 mW under 5 W pump *** carefully adjusting the insertion of BaF_(2) wedges and the optimization position of Ti:sapphire crystal in the cavity,we can obtain the smooth swings in the interferometric autocorrelation trace due to good third-order dispersion compensation.

关键词： pump wedge repetition

A Wide Spaced Femtosecond Ti:Sapphire Frequency Comb at 15 GHz by a Fabry–Pérot Filter Cavity

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Chinese Physics Letters 2013年第10期30卷 97-100页

作者： HOU Lei HAN Hai-Nian ZHANG Jin-wei LI De-Hua wei zhi-yi Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190

We realize a wide spaced frequency comb by using an external low-fineness Fabry–Pérot(F-P)cavity to filter few-cycle laser pulses from a Kerr-lens mode-locked Ti:sapphire laser at the fundamental repetition rate of 350 *** spacing as wide as 15 GHz with spectrum covered from 690 nm to 710 nm is demonstrated,corresponding to a filter multiple of about *** scanning transmission peaks after the F-P cavity with cavity lengths are also simulated numerically,and the results are in agreement with the experiment.

关键词： Femto Fabry filter

Structure and Biological Activities of Novel Triazole Compounds Containing 1,3,4-Oxadiazole Ring

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Chemical Research in Chinese Universities 2008年第3期24卷 299-302页

作者： XU Liang-zhong BI Wen-zhao SHANG Yu-qing ZHAI zhi-wei yi Xu College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 P R. China

Eighteen novel triazole compounds containing 1,3,4-oxadiazole groups were synthesized from 2-（1H-1,2,4-triazol-1-yl）acetohydrazide and carbon disulfide by several step reactions. The target compounds were characterized by elemental analysis, 1H NMR, 13C NMR, IR, MS, and X-ray crystallography. The results of preliminary biological tests show that all the compounds exhibit certain fungicidal activities.

关键词： 1H-1,2,4-Triazole 1,3,4-Oxadiazole Biological activity Crystal structure

Diagnostics of Femtosecond Laser-Plasmas Using Fundamental and Second Harmonic Emission

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Chinese Physics Letters 2000年第11期17卷 818-820页

作者： ZHAO Li-Zeng ZHANG Ping FENG Bao-Hua wei zhi-yi ZHANG Jie Laboratory of Optical Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100039

By observing the fundamental and second harmonic emission from a plasma produced by a 150fs,5mJ laser at 800nm,the electron temperature,the expansion speed and the scalelength of the plasma have been *** the polarization of the fundamental and second harmonic emission has been *** could be a useful diagnostic for modulation at the critical surface of the plasma.

关键词： polarization Femto second

High Speed Sintering:Assessing the Influence of Energy Input on Microstructure and Mechanical Properties of Polyether Block Amide(PEBA)Parts

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Chinese Journal of Polymer Science 2024年第5期42卷 675-682,I0004,I0010页

作者： Jiang-Tao Sun zhi-Yong Fan yi-wei Mao wei Li wei Zhu Dao-Sheng Cai Qing-Song wei State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430074China National Engineering Research Centre for High Efficiency Grinding Hunan UniversityChangsha410082China Wuhan EasyMFG Technology CO. LTDWuhan430074China

High speed sintering,a new powder-bed fusion additive manufacturing technology,utilizes infrared lights(IR)to intensely heat and melt polymer *** presence of defects such as porosity,which is associated with particle coalescence,is highly dependdent on the level of energy *** study investigate the influcence of energy input on porosity and its subsequent effects on the mechanical properties and microstructures of PEBA *** parts were manufactured with a variety of lamp powers,resulting in a range of energy input levels spanning from low to ***,they underwent testing using Archimedes’method,followed by tensile *** porosity,mechanical characteristics,and energy input exhibit a strong correlation;inadequate energy input was the primary cause of pore *** the reduced IR light power resulted in the following outcomes:porosity,ultimate tensile strength,and elongation of 1.37%,7.6 MPa,and 194.2%,*** the energy input was further increased,the porosity was reduced to as low as 0.05%and the ultimate tensile strength and elongation were increased to their peak values of 233.8%and 9.1 MPa,respectively.

关键词： High speed sintering Additive manufacturing Energy input Powder bed fusion PEBA

Single-atom Ag-loaded carbon nitride photocatalysts for efficient degradation of acetaminophen:The role of Ag-atom and O_(2)

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Journal of Environmental Sciences 2024年第5期139卷 12-22页

作者： yi Yuan Wen-Long Wang zhi-wei Wang Jin Wang Qian-Yuan Wu Key Laboratory of Microorganism Application and Risk Control of Shenzhen Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyInstitute of Environment and EcologyShenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Shenzhen Environmental Science and New Energy Technology Engineering Laboratory Tsinghua-Berkeley Shenzhen InstituteShenzhen 518055China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071China

Carbon nitride has been extensively used as a visible-light photocatalyst,but it has the disadvantages of a low specific surface area,rapid electron-hole recombination,and relatively low light *** this study,single-atom Ag was successfully anchored on ultrathin carbon nitride(UTCN)via thermal polymerization,the catalyst obtained is called *** Ag hardly changed the carbon nitride's layered and porous physical *** exhibited efficient visible-light photocatalytic performances in the degradation of various recalcitrant pollutants,eliminations of 85% were achieved by visible-light irradiation for *** with Ag improved the photocatalytic performance of UTCN by narrowing the forbidden band gap from 2.49 to 2.36 e V and suppressing electron-hole pair *** addition,Ag doping facilitated O_(2) adsorption on UTCN by decreasing the adsorption energy from -0.2 to -2.22 e V and favored the formation of O_(2)^(·-).Electron spin resonance and radical-quenching experiments showed that O_(2)^(·-)was the major reactive species in the degradation of Acetaminophen(paracetamol,APAP).

关键词： Ag single atom Carbon nitride Photocatalysis Visible light Adsorption energy Reactive species

Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-Qiang Zhang Qing-Lin Cheng wei Sun yi Zhao zhi-Min Li Key Lab of Ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina China Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex *** is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency *** this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is *** with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation *** comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are *** the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy *** entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their ***,the weak links in energy utilization are identified,and energy conservation and consumption reduction are *** above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction