As a novel composite processing technology, water guided laser has the advantages of small heat affected zone, good surface quality of the cut surface, strong processing depth capability and small taper compared with the traditional dry laser processing technology. In this paper, the infrared water guided laser processing technology is used to process 7075 aluminum alloy, which has high strength, high toughness and corrosion resistance and is widely used in the fields of aerospace, mechanical equipment. The processing parameters of the infrared water guided laser including the effect of 7075 aluminum alloy on the cutting depth, kerf width and surface quality at different feed speed, number of cutting times and peak power are analyzed to extend the processing method of 7075 aluminum alloy. The distance-power curve was also derived based on the fact that the further the power meter was from the nozzle, the lower the power measured within the water column. The experimental results show that the faster the 7075 aluminum alloy feed speed is, the shallower the cutting depth and the smaller the kerf width is, while the higher the number of cuts and the higher the peak power are, both will result in large cutting depth and kerf width. Finally, high quality cutting through and punching of 3mm aluminum alloy plate is achieved, which provides the theoretical basis for the study to infrared water guided laser.
{"title":"Experimental study on infrared water guided laser cutting of 7075 aluminum alloy","authors":"Zebin Pan, Guangyi Zhang, Chunhai Guo, Yang Chao, Yaowen Wu, Huan Long, Wenwu Zhang","doi":"10.1117/12.2603052","DOIUrl":"https://doi.org/10.1117/12.2603052","url":null,"abstract":"As a novel composite processing technology, water guided laser has the advantages of small heat affected zone, good surface quality of the cut surface, strong processing depth capability and small taper compared with the traditional dry laser processing technology. In this paper, the infrared water guided laser processing technology is used to process 7075 aluminum alloy, which has high strength, high toughness and corrosion resistance and is widely used in the fields of aerospace, mechanical equipment. The processing parameters of the infrared water guided laser including the effect of 7075 aluminum alloy on the cutting depth, kerf width and surface quality at different feed speed, number of cutting times and peak power are analyzed to extend the processing method of 7075 aluminum alloy. The distance-power curve was also derived based on the fact that the further the power meter was from the nozzle, the lower the power measured within the water column. The experimental results show that the faster the 7075 aluminum alloy feed speed is, the shallower the cutting depth and the smaller the kerf width is, while the higher the number of cuts and the higher the peak power are, both will result in large cutting depth and kerf width. Finally, high quality cutting through and punching of 3mm aluminum alloy plate is achieved, which provides the theoretical basis for the study to infrared water guided laser.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128527285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Zhang, Yebin Zhang, Kai Wang, Shoubao Han, Zhong Zhou, Chao Li, Lei Wang
{"title":"Sub-aperture field of view mismatch in differential synthetic aperture ladar","authors":"G. Zhang, Yebin Zhang, Kai Wang, Shoubao Han, Zhong Zhou, Chao Li, Lei Wang","doi":"10.1117/12.2602024","DOIUrl":"https://doi.org/10.1117/12.2602024","url":null,"abstract":"","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127437315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lingling Zhang, Tianjiao Shu, Guo-quan Li, Yuanchao Du, Yuan Chen, Xuanjun Zhang, J. Zhang
In order to identify and trace the single silicon wafer, which improved quality control and assists in process improvement, laser marking of silicon wafers had been an industrial standard in semiconductor industry. The traditional laser making had the depth 5-20um and a significant amount of debris. In this paper, the topography quality and the depth the size of the dot were investigated by adjusting laser pulse energy, laser pulse numbers . The results showed that the depth of the dot increases proportionally with laser irradiation energy while there were significant differences in the topography of the dot with different interaction time of laser irradiation. A free-debris laser dot marking process with the depth less than 2um, the height of bump less than 0.6um, the range of diameter of dots from 20um to 100um was achieved.
{"title":"Processing study of laser marking on Si wafer","authors":"Lingling Zhang, Tianjiao Shu, Guo-quan Li, Yuanchao Du, Yuan Chen, Xuanjun Zhang, J. Zhang","doi":"10.1117/12.2603103","DOIUrl":"https://doi.org/10.1117/12.2603103","url":null,"abstract":"In order to identify and trace the single silicon wafer, which improved quality control and assists in process improvement, laser marking of silicon wafers had been an industrial standard in semiconductor industry. The traditional laser making had the depth 5-20um and a significant amount of debris. In this paper, the topography quality and the depth the size of the dot were investigated by adjusting laser pulse energy, laser pulse numbers . The results showed that the depth of the dot increases proportionally with laser irradiation energy while there were significant differences in the topography of the dot with different interaction time of laser irradiation. A free-debris laser dot marking process with the depth less than 2um, the height of bump less than 0.6um, the range of diameter of dots from 20um to 100um was achieved.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134474692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Multiple beam generation and adaptive control plays an important role in the laser propagation applications. The existing approaches are usually mechanical, so they have many limitations in terms of accuracy, bandwidth, and flexibility. In this paper, a kind of dynamic multiple beam forming method based on the fiber laser phased array (FLPA) is proposed. In this method, the FLPA based on the multi-objective optimization algorithm is employed, which can theoretically generate any number of outgoing beams, and dynamically adjust the power of each beam. The numerical simulation experiments based on a 19-cell FLPA were conducted. The results show that two stable outgoing beams of FLPA can be generated after about 200 iterations, and the power distribution error of the two beams can reach less than 4%. In addition, the two beams can also be combined into one after about 50 iterations.
{"title":"Dynamic multiple beam forming based on the fiber laser phased array","authors":"Guan Huang, Guoyun Lv, Yangyu Fan","doi":"10.1117/12.2601327","DOIUrl":"https://doi.org/10.1117/12.2601327","url":null,"abstract":"Multiple beam generation and adaptive control plays an important role in the laser propagation applications. The existing approaches are usually mechanical, so they have many limitations in terms of accuracy, bandwidth, and flexibility. In this paper, a kind of dynamic multiple beam forming method based on the fiber laser phased array (FLPA) is proposed. In this method, the FLPA based on the multi-objective optimization algorithm is employed, which can theoretically generate any number of outgoing beams, and dynamically adjust the power of each beam. The numerical simulation experiments based on a 19-cell FLPA were conducted. The results show that two stable outgoing beams of FLPA can be generated after about 200 iterations, and the power distribution error of the two beams can reach less than 4%. In addition, the two beams can also be combined into one after about 50 iterations.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129218109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sapphire is widely used in industry, national defense, aerospace, space technology and other fields due to its excellent physical and chemical properties such as ultra-high hardness, good thermal and chemical stability, high transmittance and so on. Because of the brittleness of sapphire, edge collapse and fragmentation are occurring easily during the process of traditional mechanical machining. Therefore, development of a rapid and high-quality processing method has great significance. Compared with continuous / long pulse laser processing, femtosecond laser processing with ultra-short duration and extremely high peak power has the advantages of small thermal effect, high processing accuracy, real three-dimensional and wide material adaptability. In this paper, a method of machining sapphire with a center wavelength of 515 nm femtosecond laser and scanning galvanometer is proposed. The effects of laser power, processing speed and scanning pitch on the machining depth and surface roughness are studied. A 3D structure is fabricated by combining a scanning galvanometer and the XYZ platform with high speed. Finally, two types of arrays of 3D structure have been fabricated on sapphire, which has high machined surface quality.
{"title":"Research on 3D high speed precision machining of sapphire based on femtosecond laser","authors":"Zhihao Chen, Hongbing Yuan, Peichao Wu, Ling Zhao, Mina Zhang, Xiaowen Cao, Wenwu Zhang","doi":"10.1117/12.2602942","DOIUrl":"https://doi.org/10.1117/12.2602942","url":null,"abstract":"Sapphire is widely used in industry, national defense, aerospace, space technology and other fields due to its excellent physical and chemical properties such as ultra-high hardness, good thermal and chemical stability, high transmittance and so on. Because of the brittleness of sapphire, edge collapse and fragmentation are occurring easily during the process of traditional mechanical machining. Therefore, development of a rapid and high-quality processing method has great significance. Compared with continuous / long pulse laser processing, femtosecond laser processing with ultra-short duration and extremely high peak power has the advantages of small thermal effect, high processing accuracy, real three-dimensional and wide material adaptability. In this paper, a method of machining sapphire with a center wavelength of 515 nm femtosecond laser and scanning galvanometer is proposed. The effects of laser power, processing speed and scanning pitch on the machining depth and surface roughness are studied. A 3D structure is fabricated by combining a scanning galvanometer and the XYZ platform with high speed. Finally, two types of arrays of 3D structure have been fabricated on sapphire, which has high machined surface quality.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"311 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114714334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chenxu Wang, H. Bian, Zhanda Zhu, Yongling Hui, H. Lei, Qiang Li
It’s an effective method to produce mid infrared laser that CO2 laser frequency doubling by using quasi-phase-matched (QPM) crystal. The main problem in the preparing diffusion bonding crystal is controlling the defects. In this paper, the bonding temperature, pressure, time and other parameters are optimized to reduce the interface loss. When the bonding temperature is 700°C , the bonding pressure of 0.27kg/mm2, a 49 layer QPM GaAs crystal was fabricated, and the interface loss of the single layer was less than 0.13%. Using the prepared QPM-GaAs crystal for second harmonic generation, 23% SHG efficiency was achieved in a CO2 laser with 10.56μm wavelength, 219 mJ pulse energy and 110 ns pulse width.
{"title":"Optimization of diffusion bonding process for QPM GaAs crystals","authors":"Chenxu Wang, H. Bian, Zhanda Zhu, Yongling Hui, H. Lei, Qiang Li","doi":"10.1117/12.2602985","DOIUrl":"https://doi.org/10.1117/12.2602985","url":null,"abstract":"It’s an effective method to produce mid infrared laser that CO2 laser frequency doubling by using quasi-phase-matched (QPM) crystal. The main problem in the preparing diffusion bonding crystal is controlling the defects. In this paper, the bonding temperature, pressure, time and other parameters are optimized to reduce the interface loss. When the bonding temperature is 700°C , the bonding pressure of 0.27kg/mm2, a 49 layer QPM GaAs crystal was fabricated, and the interface loss of the single layer was less than 0.13%. Using the prepared QPM-GaAs crystal for second harmonic generation, 23% SHG efficiency was achieved in a CO2 laser with 10.56μm wavelength, 219 mJ pulse energy and 110 ns pulse width.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115748865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The nonlinear Thomson backscattering process of electron under circularly polarized laser pulses is studied. The influence of the central collision position of the electron and laser pulses on the spectral characteristics of the scattered light is analyzed. The results show that the frequency broadening caused by doppler nonlinear frequency shift can be reduced and the monochromicity of the emitted light can be improved by adjusting the central collision position or the initial position of electron appropriately. At the same time, taking the requirements for the radiation intensity of scattered light into account, the optimal situation to generate quasi-monochromatic x-rays is presented. Besides, a scheme to increase the radiation energy of backscattered light by controlling the laser pulse width is proposed without changing the frequency band width. It provides a solution to overcome the problem that the radiation energy is too weak in the scheme of changing the initial position of electron. In addition, it was found that the interference fringes of the emitted light growing greatly as the pulse width increases.
{"title":"Generation of a quasi-monochromatic x-ray via collision of electron with tightly focused laser pulses","authors":"J. Zhuang, Yiqiu Wang, Conglin Wang, Youwei Tian","doi":"10.1117/12.2600762","DOIUrl":"https://doi.org/10.1117/12.2600762","url":null,"abstract":"The nonlinear Thomson backscattering process of electron under circularly polarized laser pulses is studied. The influence of the central collision position of the electron and laser pulses on the spectral characteristics of the scattered light is analyzed. The results show that the frequency broadening caused by doppler nonlinear frequency shift can be reduced and the monochromicity of the emitted light can be improved by adjusting the central collision position or the initial position of electron appropriately. At the same time, taking the requirements for the radiation intensity of scattered light into account, the optimal situation to generate quasi-monochromatic x-rays is presented. Besides, a scheme to increase the radiation energy of backscattered light by controlling the laser pulse width is proposed without changing the frequency band width. It provides a solution to overcome the problem that the radiation energy is too weak in the scheme of changing the initial position of electron. In addition, it was found that the interference fringes of the emitted light growing greatly as the pulse width increases.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"12367 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116178869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Background interference of impurity in strong water is the key factor restricting the detection distance and target characteristics of the weak target. Aiming at the problems of less echo characteristics and difficult identification of the characteristics of the underwater weak target laser detection, the paper studies the problem of the broadening of the laser echo pulse of the weak target under the background of strong water interference. A system of underwater weak target laser measurement and analysis is designed to suppress the near-field water scattering interference. The system can achieve matching adjustment among laser emission energy, laser beam angle and laser APD receiving gain. The detection performance of different underwater weak targets (small-scale metal, black rubber, low reflectivity reef, water grass, transparent plastic) was tested under different laser emission energy, different detection distance and different laser echo receiving gain. Through statistical analysis of data, the pulse width and material of the target of different underwater weak targets were obtained The relationship between the power of pulse laser, the distance between laser emission and target. The results show that the pulse broadening characteristics of the laser echo signal can be used to identify the weak target laser detection characteristics under the background of strong water impurity interference.
{"title":"Study on the characteristics of underwater target laser echo based on pulse broadening","authors":"Yujia Wang, S. Zong, Xin Zhang","doi":"10.1117/12.2603111","DOIUrl":"https://doi.org/10.1117/12.2603111","url":null,"abstract":"Background interference of impurity in strong water is the key factor restricting the detection distance and target characteristics of the weak target. Aiming at the problems of less echo characteristics and difficult identification of the characteristics of the underwater weak target laser detection, the paper studies the problem of the broadening of the laser echo pulse of the weak target under the background of strong water interference. A system of underwater weak target laser measurement and analysis is designed to suppress the near-field water scattering interference. The system can achieve matching adjustment among laser emission energy, laser beam angle and laser APD receiving gain. The detection performance of different underwater weak targets (small-scale metal, black rubber, low reflectivity reef, water grass, transparent plastic) was tested under different laser emission energy, different detection distance and different laser echo receiving gain. Through statistical analysis of data, the pulse width and material of the target of different underwater weak targets were obtained The relationship between the power of pulse laser, the distance between laser emission and target. The results show that the pulse broadening characteristics of the laser echo signal can be used to identify the weak target laser detection characteristics under the background of strong water impurity interference.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"278 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120879203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
When the aircraft is flying in the air at high speed, it will compress the surrounding air to form a shock wave layer on the front of aircraft, and the shock wave will gradually turn into turbulence as the distance from the front of the aircraft increases. When the shock wave turns into turbulence, the air is weakly compressible, and the laser will be distorted when it is transmitted in the air, and the intensity will attenuate. In this paper, Gaussian beam is used as the beam source, combined with Rytov theory, the expression of the intensity of Gaussian beam propagation in weakly compressible flow is derived. The results show that air density is an important factor affecting the attenuation of intensity, and the influence of air pressure cannot be ignored. Increasing the beam waist width can resist the attenuation of intensity to a certain extent. It is different from the turbulent atmosphere that the beam attenuation is greater in weakly compressible flows, which must be considered when discuss the attenuation of aerospace communication signals.
{"title":"Analysis of propagation characteristics of Gaussian beam in weakly compressible flow","authors":"Jinyu Xie, L. Bai, Yankun Wang","doi":"10.1117/12.2601813","DOIUrl":"https://doi.org/10.1117/12.2601813","url":null,"abstract":"When the aircraft is flying in the air at high speed, it will compress the surrounding air to form a shock wave layer on the front of aircraft, and the shock wave will gradually turn into turbulence as the distance from the front of the aircraft increases. When the shock wave turns into turbulence, the air is weakly compressible, and the laser will be distorted when it is transmitted in the air, and the intensity will attenuate. In this paper, Gaussian beam is used as the beam source, combined with Rytov theory, the expression of the intensity of Gaussian beam propagation in weakly compressible flow is derived. The results show that air density is an important factor affecting the attenuation of intensity, and the influence of air pressure cannot be ignored. Increasing the beam waist width can resist the attenuation of intensity to a certain extent. It is different from the turbulent atmosphere that the beam attenuation is greater in weakly compressible flows, which must be considered when discuss the attenuation of aerospace communication signals.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116882364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Du Juan, Zhu Jingguo, Jiang Chenghao, Qiao Zhi, H. Zhihong, Cao Kang, Wang Chunxiao, Zuo Yong
As a classic radar signal processing method, pulse compression technology can effectively increase the measurement distance while ensuring the ranging resolution, so as to achieve long-distance high-precision measurement. Waveform modulation techniques commonly used for pulse compression include linear frequency modulation and phase code modulation. In this paper, we proposed a method of laser ranging technology based on pulse compression, briefly analyzing two waveform modulation techniques and exploring the relationship between modulation bandwidth and ranging accuracy based on the linear frequency modulation ranging model. The results indicated that the ranging accuracy fluctuated greatly when the modulation bandwidth was changed. The measurement error would be stable within 10mm when the modulation bandwidth was on the order of GHz. The method would be expected to provide a certain reference for the choice of laser modulation bandwidth in the field of long-distance high-precision laser measurement.
{"title":"Research and simulation analysis of laser ranging technology based on pulse compression","authors":"Du Juan, Zhu Jingguo, Jiang Chenghao, Qiao Zhi, H. Zhihong, Cao Kang, Wang Chunxiao, Zuo Yong","doi":"10.1117/12.2603168","DOIUrl":"https://doi.org/10.1117/12.2603168","url":null,"abstract":"As a classic radar signal processing method, pulse compression technology can effectively increase the measurement distance while ensuring the ranging resolution, so as to achieve long-distance high-precision measurement. Waveform modulation techniques commonly used for pulse compression include linear frequency modulation and phase code modulation. In this paper, we proposed a method of laser ranging technology based on pulse compression, briefly analyzing two waveform modulation techniques and exploring the relationship between modulation bandwidth and ranging accuracy based on the linear frequency modulation ranging model. The results indicated that the ranging accuracy fluctuated greatly when the modulation bandwidth was changed. The measurement error would be stable within 10mm when the modulation bandwidth was on the order of GHz. The method would be expected to provide a certain reference for the choice of laser modulation bandwidth in the field of long-distance high-precision laser measurement.","PeriodicalId":330466,"journal":{"name":"Sixteenth National Conference on Laser Technology and Optoelectronics","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117148134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：