Zhongyu Zhou, Z. Gu, F. Tan, Jianheng Zhao, Chengwei Sun, Cangli Liu
A complex impedance measurement device with a short response time and high noise immunity is presented in this paper. The device based on a radio-frequency reflectometer was specially developed for electro-physical property investigations of materials in quasi-isentropic compression experiments. The maximum operating frequency of the device is up to 600 MHz for reducing intense low-frequency noises. Meanwhile, an off-line signal processing code was developed to improve the response time of the device to less than 10 ns. Using the device, the complex impedance and electrical conductivity of water compressed by an explosive-driven magnetic flux compression generator were measured, and an abrupt change in the complex impedance of water caused by a liquid-solid transition was directly observed under intense electromagnetic interference.
{"title":"Development of a transient complex impedance measurement device used in quasi-isentropic compression experiments.","authors":"Zhongyu Zhou, Z. Gu, F. Tan, Jianheng Zhao, Chengwei Sun, Cangli Liu","doi":"10.1063/5.0079336","DOIUrl":"https://doi.org/10.1063/5.0079336","url":null,"abstract":"A complex impedance measurement device with a short response time and high noise immunity is presented in this paper. The device based on a radio-frequency reflectometer was specially developed for electro-physical property investigations of materials in quasi-isentropic compression experiments. The maximum operating frequency of the device is up to 600 MHz for reducing intense low-frequency noises. Meanwhile, an off-line signal processing code was developed to improve the response time of the device to less than 10 ns. Using the device, the complex impedance and electrical conductivity of water compressed by an explosive-driven magnetic flux compression generator were measured, and an abrupt change in the complex impedance of water caused by a liquid-solid transition was directly observed under intense electromagnetic interference.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"130 1","pages":"054701"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85134755","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 radio frequency telecommunication at a kilohertz range through an electrically conductive medium is often impeded by the strong reflection and absorption at the interface. The polarization helicity of the magnetic field can be modulated/demodulated to provide a new communication protocol to potentiality circumvent these issues. Here, a miniature magnetic quantum receiver, capable of simultaneously discriminating the two possible helicities of a magnetic field, is presented. The core physics package constitutes two optically pumped atomic magnetometers. It is shown that a data rate of 500 bits/s with a carrier frequency of 2 kHz can be efficiently demodulated in an unshielded environment, paving a promising route for the future of radio frequency communication through a conductive barrier.
{"title":"Magnetic communication by polarization helicity modulation using atomic magnetometers.","authors":"I. Fan, S. Knappe, V. Gerginov","doi":"10.1063/5.0086169","DOIUrl":"https://doi.org/10.1063/5.0086169","url":null,"abstract":"The radio frequency telecommunication at a kilohertz range through an electrically conductive medium is often impeded by the strong reflection and absorption at the interface. The polarization helicity of the magnetic field can be modulated/demodulated to provide a new communication protocol to potentiality circumvent these issues. Here, a miniature magnetic quantum receiver, capable of simultaneously discriminating the two possible helicities of a magnetic field, is presented. The core physics package constitutes two optically pumped atomic magnetometers. It is shown that a data rate of 500 bits/s with a carrier frequency of 2 kHz can be efficiently demodulated in an unshielded environment, paving a promising route for the future of radio frequency communication through a conductive barrier.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"127 1","pages":"053004"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86301335","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}
Jie Wang, Yong Gao, Yaocheng Hu, Jing Zhang, Z. You, Q. Sun, Q. Si, Zhanglian Xu, Sheng Wang, Guoming Liu, Aijun Mi
The first results on the activation process and mechanisms of novel quinary alloy Ti-Zr-V-Hf-Nb non-evaporable getter (NEG) film coatings with copper substrates were presented. About 1.075 µm of Ti-Zr-V-Hf-Nb NEG film coating was deposited on the copper substrates by using the DC sputtering method. The NEG activation at 100, 150, and 180 °C, respectively, for 2 h was in situ characterized by x-ray photoelectron spectroscopy (XPS). The as-deposited NEG film mainly comprised the high valence state metallic oxides and the sub-oxides, as well as a small number of metals. The in situ XPS studies indicated that the concentrations of the high-oxidized states of Ti, Zr, V, Hf, and Nb gradually decreased and that of the lower valence metallic oxides and metallic states increased in steps, when the activation temperature increased from 100 to 180 °C. This outcome manifested that these novel quinary alloy Ti-Zr-V-Hf-Nb NEG film coatings could be activated and used for producing ultra-high vacuum.
{"title":"Activation characterization of a novel quinary alloy Ti-Zr-V-Hf-Nb non-evaporable getters by x-ray photoelectron spectroscopy.","authors":"Jie Wang, Yong Gao, Yaocheng Hu, Jing Zhang, Z. You, Q. Sun, Q. Si, Zhanglian Xu, Sheng Wang, Guoming Liu, Aijun Mi","doi":"10.1063/5.0079537","DOIUrl":"https://doi.org/10.1063/5.0079537","url":null,"abstract":"The first results on the activation process and mechanisms of novel quinary alloy Ti-Zr-V-Hf-Nb non-evaporable getter (NEG) film coatings with copper substrates were presented. About 1.075 µm of Ti-Zr-V-Hf-Nb NEG film coating was deposited on the copper substrates by using the DC sputtering method. The NEG activation at 100, 150, and 180 °C, respectively, for 2 h was in situ characterized by x-ray photoelectron spectroscopy (XPS). The as-deposited NEG film mainly comprised the high valence state metallic oxides and the sub-oxides, as well as a small number of metals. The in situ XPS studies indicated that the concentrations of the high-oxidized states of Ti, Zr, V, Hf, and Nb gradually decreased and that of the lower valence metallic oxides and metallic states increased in steps, when the activation temperature increased from 100 to 180 °C. This outcome manifested that these novel quinary alloy Ti-Zr-V-Hf-Nb NEG film coatings could be activated and used for producing ultra-high vacuum.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"80 1","pages":"053906"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83865637","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}
Huifang Liu, Weiwei Dong, Yunlong Chang, Yifei Gao, Wencheng Li
The practice of harvesting vibration energy from machine tools, windmill blades, etc., and converting it into electric energy to power low-power electronic circuits has attracted wide attention from experts and scholars. Abundant vibrations that exist in the moving vehicle can be harvested to power sensors in tire pressure monitoring. In this paper, for the first time, a device is proposed to harvest the rotational vibration energy with the iron-gallium alloy (magnetostrictive material) as the core material. Such a device utilizes the coupling characteristics of Villarreal effect and Faraday electromagnetic effect to convert the vibration energy generated by the moving vehicle into electric energy. Upon completion of the design of the magnetostrictive rotational vibration energy harvester, the influence law of key factors, including substrate material, substrate size, and pre-magnetization field arrangement on the harvesting capability of the device, was studied in detail through experiments. An electric motor and vibration exciter were used to apply varied excitation forms to the harvester, and the output patterns of the harvester under conditions of wheel rotation, road bumps, and random vibration were fully analyzed. In addition, the correlation between the deformation of the cantilever beam and harvester performance was also investigated. The results have shown that at the acceleration of 9.6 g and the rotational speed of 90 r/min, the harvester can reach the output voltage of 1.22 V. Consequently, it demonstrates the feasibility of employing the magnetostrictive harvester to gather rotational vibration energy and provides theoretical guidance for further and deeper research on the harvester.
{"title":"Working characteristics of a magnetostrictive vibration energy harvester for rotating car wheels.","authors":"Huifang Liu, Weiwei Dong, Yunlong Chang, Yifei Gao, Wencheng Li","doi":"10.1063/5.0078131","DOIUrl":"https://doi.org/10.1063/5.0078131","url":null,"abstract":"The practice of harvesting vibration energy from machine tools, windmill blades, etc., and converting it into electric energy to power low-power electronic circuits has attracted wide attention from experts and scholars. Abundant vibrations that exist in the moving vehicle can be harvested to power sensors in tire pressure monitoring. In this paper, for the first time, a device is proposed to harvest the rotational vibration energy with the iron-gallium alloy (magnetostrictive material) as the core material. Such a device utilizes the coupling characteristics of Villarreal effect and Faraday electromagnetic effect to convert the vibration energy generated by the moving vehicle into electric energy. Upon completion of the design of the magnetostrictive rotational vibration energy harvester, the influence law of key factors, including substrate material, substrate size, and pre-magnetization field arrangement on the harvesting capability of the device, was studied in detail through experiments. An electric motor and vibration exciter were used to apply varied excitation forms to the harvester, and the output patterns of the harvester under conditions of wheel rotation, road bumps, and random vibration were fully analyzed. In addition, the correlation between the deformation of the cantilever beam and harvester performance was also investigated. The results have shown that at the acceleration of 9.6 g and the rotational speed of 90 r/min, the harvester can reach the output voltage of 1.22 V. Consequently, it demonstrates the feasibility of employing the magnetostrictive harvester to gather rotational vibration energy and provides theoretical guidance for further and deeper research on the harvester.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"93 1","pages":"055001"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83863634","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}
X. Zhao, X. Yuan, J. Zheng, Y. Dong, K. Glize, Y. Zhang, Z. Zhang, J. Zhang
We developed an angular-resolved scattered-light diagnostic station (ARSDS) to extend the study of laser-plasma instabilities (LPIs) by simultaneously diagnosing their features at different angles in a single shot. The ARSDS angularly samples the scattered light using an array of fibers with flexible setups. The collected light is detected with an imaging spectrometer, a streaked spectrometer, or a fiber-optic spectrometer to provide time-integrated/time-resolved spectral information. The ARSDS was implemented at Shenguang-II Upgrade laser facility for the double-cone ignition campaigns. Preliminary results confirm the importance of an angular-resolved detection due to the angular dependence of LPI processes, such as stimulated Raman scattering.
{"title":"An angular-resolved scattered-light diagnostic for laser-plasma instability studies.","authors":"X. Zhao, X. Yuan, J. Zheng, Y. Dong, K. Glize, Y. Zhang, Z. Zhang, J. Zhang","doi":"10.1063/5.0090841","DOIUrl":"https://doi.org/10.1063/5.0090841","url":null,"abstract":"We developed an angular-resolved scattered-light diagnostic station (ARSDS) to extend the study of laser-plasma instabilities (LPIs) by simultaneously diagnosing their features at different angles in a single shot. The ARSDS angularly samples the scattered light using an array of fibers with flexible setups. The collected light is detected with an imaging spectrometer, a streaked spectrometer, or a fiber-optic spectrometer to provide time-integrated/time-resolved spectral information. The ARSDS was implemented at Shenguang-II Upgrade laser facility for the double-cone ignition campaigns. Preliminary results confirm the importance of an angular-resolved detection due to the angular dependence of LPI processes, such as stimulated Raman scattering.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"51 1","pages":"053505"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77824323","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}
Duan Chi, Wang Zhi, Hao Luo, Fengfa Li, Lianzhong Sun
In recent years, vision screening has emerged globally for employment (on a yearly basis) within primary and high schools since myopia heavily affects school-aged children. However, this is a laborious and time-consuming task. This article proposes an intelligent system for "self-service" vision screening. Individuals can accomplish this task independently-without any assistance by technical staff. The technical solution involved within this platform is human action recognition realized by pose estimation (real-time human joint localization in images, including detection, association, and tracking). The developed system is based on a compact and embedded artificial intelligence platform, aided by a red-green-blue-D sensor for ranging and pose extraction. A set of intuitive upper-limb actions was designed for unambiguous recognition and interaction. The deployment of this intelligent system brings great convenience for large-scale and rapid vision screening. Implementation details were extensively described, and the experimental results demonstrated efficiency for the proposed technique.
{"title":"Embedded AI system for interactive vision screen based on human action recognition.","authors":"Duan Chi, Wang Zhi, Hao Luo, Fengfa Li, Lianzhong Sun","doi":"10.1063/5.0076398","DOIUrl":"https://doi.org/10.1063/5.0076398","url":null,"abstract":"In recent years, vision screening has emerged globally for employment (on a yearly basis) within primary and high schools since myopia heavily affects school-aged children. However, this is a laborious and time-consuming task. This article proposes an intelligent system for \"self-service\" vision screening. Individuals can accomplish this task independently-without any assistance by technical staff. The technical solution involved within this platform is human action recognition realized by pose estimation (real-time human joint localization in images, including detection, association, and tracking). The developed system is based on a compact and embedded artificial intelligence platform, aided by a red-green-blue-D sensor for ranging and pose extraction. A set of intuitive upper-limb actions was designed for unambiguous recognition and interaction. The deployment of this intelligent system brings great convenience for large-scale and rapid vision screening. Implementation details were extensively described, and the experimental results demonstrated efficiency for the proposed technique.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"29 1","pages":"054104"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75894576","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}
H. Li, S. J. Li, Q. Xie, J. H. Liu, R. H. Bai, R. Y. Tao, X. Lun, N. Li, X. Bo, C. Liu, L. Han, B. Deng
A 15-point Thomson scattering diagnostic system is developed for ENN's spherical torus experiment XuanLong-50 (EXL-50). A BeamTech laser with 3 J/pulse (1064 nm wavelength) at 50 Hz repetition rate is chosen for measurements during EXL-50 plasma operations. To enable measurements at low density (∼0.5 × 1018 m-3) plasma operations, the opto-mechanical subsystems are carefully designed to maximize the collection and transmission of the scattered light and to minimize the stray light level. In addition, the high bandwidth trans-impedance amplifiers and segmented high speed waveform digitizers allow for the application of muti-pulse averaging to further improve the signal-to-noise ratio. Details of the diagnostic system are described and initial experimental results are presented.
{"title":"Thomson scattering diagnostic system for the XuanLong-50 experiment.","authors":"H. Li, S. J. Li, Q. Xie, J. H. Liu, R. H. Bai, R. Y. Tao, X. Lun, N. Li, X. Bo, C. Liu, L. Han, B. Deng","doi":"10.1063/5.0088785","DOIUrl":"https://doi.org/10.1063/5.0088785","url":null,"abstract":"A 15-point Thomson scattering diagnostic system is developed for ENN's spherical torus experiment XuanLong-50 (EXL-50). A BeamTech laser with 3 J/pulse (1064 nm wavelength) at 50 Hz repetition rate is chosen for measurements during EXL-50 plasma operations. To enable measurements at low density (∼0.5 × 1018 m-3) plasma operations, the opto-mechanical subsystems are carefully designed to maximize the collection and transmission of the scattered light and to minimize the stray light level. In addition, the high bandwidth trans-impedance amplifiers and segmented high speed waveform digitizers allow for the application of muti-pulse averaging to further improve the signal-to-noise ratio. Details of the diagnostic system are described and initial experimental results are presented.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"20 1","pages":"053504"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83281304","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}
This study proposes an improved high-voltage fast impulse generator based on an inductive energy storage system with a 4 kV static induction thyristor. Nanosecond-scale impulses with pulse widths below 100 ns and a peak voltage of up to 15 kV can be generated by modifying the high-voltage transformer in the circuit and tuning the circuit capacitor. The resulting device is highly stable and can perform continuously if the discharge parameters are chosen within the recommended range. A plasma jet was operated using the generator at low temperature (below 37 °C). Together with its high stability and potential for continuous operation, the proposed generator offers promise for use in biomedical and agricultural applications. Furthermore, the nanosecond-scale high-voltage impulses produced by the generator enable it to achieve an electron density in the plasma one order of magnitude higher than the commercially available radio frequency plasma jet analog. We also show how to reduce the total cost of the generator.
{"title":"Nanosecond-scale impulse generator for biomedical applications of atmospheric-pressure plasma technology.","authors":"Vladislav Gamaleev, Naohiro Shimizu, M. Hori","doi":"10.1063/5.0082175","DOIUrl":"https://doi.org/10.1063/5.0082175","url":null,"abstract":"This study proposes an improved high-voltage fast impulse generator based on an inductive energy storage system with a 4 kV static induction thyristor. Nanosecond-scale impulses with pulse widths below 100 ns and a peak voltage of up to 15 kV can be generated by modifying the high-voltage transformer in the circuit and tuning the circuit capacitor. The resulting device is highly stable and can perform continuously if the discharge parameters are chosen within the recommended range. A plasma jet was operated using the generator at low temperature (below 37 °C). Together with its high stability and potential for continuous operation, the proposed generator offers promise for use in biomedical and agricultural applications. Furthermore, the nanosecond-scale high-voltage impulses produced by the generator enable it to achieve an electron density in the plasma one order of magnitude higher than the commercially available radio frequency plasma jet analog. We also show how to reduce the total cost of the generator.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"29 1","pages":"053503"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86497205","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}
L. Riu, C. Pilorget, V. Hamm, J. Bibring, C. Lantz, D. Loizeau, R. Brunetto, J. Carter, G. Lequertier, L. Lourit, T. Okada, K. Yogata, K. Hatakeda, A. Nakato, T. Yada
MicrOmega, a miniaturized near-infrared hyperspectral microscope, has been selected to characterize in the laboratory the samples returned from Ryugu by the Hayabusa2 mission. MicrOmega has been delivered to the Extraterrestrial Samples Curation Center of the Japanese Aerospace eXploration Agency at the Institute of Space and Astronautical Science in July 2020 and then mounted and calibrated to be ready for the analyses of the samples returned to Earth on December 6, 2020. MicrOmega was designed to analyze the returned samples within a field of view of 5 × 5 mm2 and a spatial sampling of 22.5 µm. It acquires 3D near-infrared hyperspectral image-cubes by imaging the sample with monochromatic images sequentially covering the 0.99-3.65 µm spectral range, with a typical spectral sampling of 20 cm-1. This paper reports the calibration processes performed to extract scientific data from these MicrOmega image-cubes. The determination of the instrumental response and the spectral calibration is detailed. We meet or exceed the goals of achieving an accuracy of ∼20% for the absolute reflectance level, 1% for the relative wavelength-to-wavelength reflectance, and <5 nm for the peak position of the detected absorption features. For the nominal measurements of Ryugu samples with MicrOmega/Curation, the instrument performance also reaches a signal-to-noise ratio of >100 over the entire spectral range. By characterizing the entire collection of the returned samples at the microscopic scale, MicrOmega/Curation offers the potential to provide unprecedented insights into the composition and history of their asteroid parent body.
{"title":"Calibration and performances of the MicrOmega instrument for the characterization of asteroid Ryugu returned samples.","authors":"L. Riu, C. Pilorget, V. Hamm, J. Bibring, C. Lantz, D. Loizeau, R. Brunetto, J. Carter, G. Lequertier, L. Lourit, T. Okada, K. Yogata, K. Hatakeda, A. Nakato, T. Yada","doi":"10.1063/5.0082456","DOIUrl":"https://doi.org/10.1063/5.0082456","url":null,"abstract":"MicrOmega, a miniaturized near-infrared hyperspectral microscope, has been selected to characterize in the laboratory the samples returned from Ryugu by the Hayabusa2 mission. MicrOmega has been delivered to the Extraterrestrial Samples Curation Center of the Japanese Aerospace eXploration Agency at the Institute of Space and Astronautical Science in July 2020 and then mounted and calibrated to be ready for the analyses of the samples returned to Earth on December 6, 2020. MicrOmega was designed to analyze the returned samples within a field of view of 5 × 5 mm2 and a spatial sampling of 22.5 µm. It acquires 3D near-infrared hyperspectral image-cubes by imaging the sample with monochromatic images sequentially covering the 0.99-3.65 µm spectral range, with a typical spectral sampling of 20 cm-1. This paper reports the calibration processes performed to extract scientific data from these MicrOmega image-cubes. The determination of the instrumental response and the spectral calibration is detailed. We meet or exceed the goals of achieving an accuracy of ∼20% for the absolute reflectance level, 1% for the relative wavelength-to-wavelength reflectance, and <5 nm for the peak position of the detected absorption features. For the nominal measurements of Ryugu samples with MicrOmega/Curation, the instrument performance also reaches a signal-to-noise ratio of >100 over the entire spectral range. By characterizing the entire collection of the returned samples at the microscopic scale, MicrOmega/Curation offers the potential to provide unprecedented insights into the composition and history of their asteroid parent body.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"15 1","pages":"054503"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87844777","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}
J. Qin, Zihan Zhang, Yanwen Li, Y. Cai, Hongqiang Zhang, Lianhua Liu, Lijin Xu, Weidong Zhang, Xiao Xue
The obscure theory of passive subambient daytime radiative cooling (PSDRC) was deduced in a more understandable way using an arithmetic formula rather than integro-differential equations. Based on two boundary conditions of the equations, an innovative radiative cooler was successfully developed to qualitatively observe PSDRC phenomena and quantitatively characterize the cooling effect and cooling power of radiative cooling coatings (RC coatings). The remarkable subambient temperature reduction over 4.0 °C was successfully achieved in a completely open environment without minimizing the parasitic conduction and convection from the ambient. Prominent PSDRC phenomena could even be observed in such an open environment on very cloudy days, which generally compromise the RC. A much more prominent subambient cooling depression of 10.0 °C was observed when a wind shield was employed to minimize the convection. With suppression of convection, the subambient daytime cooling effect on cloudy days was even more noticeable than that occurred on clear sunny days. The subambient cooling effect was still very remarkable even on clear sunny days in the winter. The average cooling power measured on a clear sunny day was 154.8 ± 9.7 W/m2, corresponding to an average solar irradiance of 680 ± 90 W/m2 with a peak value of ∼820 W/m2. Both the subambient RC effect and the cooling power measured under real weather conditions using the radiative cooler agreed excellently with the theoretical prediction, sufficiently demonstrating the great innovation, validity, and effectiveness of the device.
{"title":"Design and manufacture of a radiative cooler to measure the subambient cooling effect and cooling power.","authors":"J. Qin, Zihan Zhang, Yanwen Li, Y. Cai, Hongqiang Zhang, Lianhua Liu, Lijin Xu, Weidong Zhang, Xiao Xue","doi":"10.1063/5.0087494","DOIUrl":"https://doi.org/10.1063/5.0087494","url":null,"abstract":"The obscure theory of passive subambient daytime radiative cooling (PSDRC) was deduced in a more understandable way using an arithmetic formula rather than integro-differential equations. Based on two boundary conditions of the equations, an innovative radiative cooler was successfully developed to qualitatively observe PSDRC phenomena and quantitatively characterize the cooling effect and cooling power of radiative cooling coatings (RC coatings). The remarkable subambient temperature reduction over 4.0 °C was successfully achieved in a completely open environment without minimizing the parasitic conduction and convection from the ambient. Prominent PSDRC phenomena could even be observed in such an open environment on very cloudy days, which generally compromise the RC. A much more prominent subambient cooling depression of 10.0 °C was observed when a wind shield was employed to minimize the convection. With suppression of convection, the subambient daytime cooling effect on cloudy days was even more noticeable than that occurred on clear sunny days. The subambient cooling effect was still very remarkable even on clear sunny days in the winter. The average cooling power measured on a clear sunny day was 154.8 ± 9.7 W/m2, corresponding to an average solar irradiance of 680 ± 90 W/m2 with a peak value of ∼820 W/m2. Both the subambient RC effect and the cooling power measured under real weather conditions using the radiative cooler agreed excellently with the theoretical prediction, sufficiently demonstrating the great innovation, validity, and effectiveness of the device.","PeriodicalId":54761,"journal":{"name":"Journal of the Optical Society of America and Review of Scientific Instruments","volume":"53 2 1","pages":"054901"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90809372","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}