Journals >Journal of Atmospheric and Environmental Optics
Contents
2020
Volume: 15 Issue 4
9 Article(s)
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[in Chinese]
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 1 (2020)
Error Analysis of Calculated Limb Radiances of Atmospheric Ultra-High Spectral Detector—Uncertainty Experiment of Four Atmospheric Components
Xuemei ZONG
Using the RFM model, the limb radiance errors of the four main atmospheric components (CO2, O3, H2O and N2O) in the radiative transfer observed by atmospheric infrared ultra-high spectral detector due to the uncertainty of the position, intensity and width of the absorption lines were simulated. Based on the statisticsUsing the RFM model, the limb radiance errors of the four main atmospheric components (CO2, O3, H2O and N2O) in the radiative transfer observed by atmospheric infrared ultra-high spectral detector due to the uncertainty of the position, intensity and width of the absorption lines were simulated. Based on the statistics of molecular absorption line uncertainty code in HITRAN2016 database, the value whose uncertainty code is not less than 3 was used in radiation transmission calculation. It is found that the uncertainty of the absorption lines of different molecules has different effects on the limb radiances at different tangent heights, and the uncertainty factors play different role separately or mutually. Meanwhile, the radiance absolute and relative errors caused by the three uncertain factors of the atmospheric molecules were also simulated and calculated in four infrared bands of the detector, which provides data basis for spectral channel selection and atmospheric parameter inversion..
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 241 (2020)
Comparative Analysis of Observed Values Based on Three Different Types of Sunshine Detectors
Li DING, Shuangxi LIU, Jingbo HU, Jie QIU, Lei WANG, and Xufeng YU
By comparing the sunshine durations obtained by Jordan sunshine recorder and the two automatic observation sunshine detectors (FS-RZ1 sunshine sensor and FS-ST series automatic solar tracker, abbreviated as FS-RZ1 and FS-ST respectively) during May-August2018 in Huzhou, Changxing, and Deqing, Zhejiang, China, and statiBy comparing the sunshine durations obtained by Jordan sunshine recorder and the two automatic observation sunshine detectors (FS-RZ1 sunshine sensor and FS-ST series automatic solar tracker, abbreviated as FS-RZ1 and FS-ST respectively) during May-August2018 in Huzhou, Changxing, and Deqing, Zhejiang, China, and statistically analyzing the relative difference between the daily sunshine durations of the three detectors, it is found that the observation values of the three detectors are highly correlated . In comparison, there is a high degree of credibility of sunshine duration obtained by the automatic observation detector, and the sunshine durations of FS-RZ1 and FS-ST are generally lower than those of Jordan sunshine recorder. The correlation of FS-ST and Jordan sunshine recorder can reach about 0.99, which is slightly higher than that of FS-RZ1 and Jordan sunshine recorder. This difference may be related to whether the Deqing station observers have the awareness to do a comparison of artificial and automatic observations. The analysis also shows that the detection environment, local weather conditions and the difference in the operational quality of station observers are the main factors that affect the relative difference between artificial and automatic sunshine duration..
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 251 (2020)
Intensity Distribution and Coherence Characteristics of Partially Coherent Light in Horizontal Atmospheric Propagation
Jianying REN, Huayan SUN, Yanzhong ZHAO, and Laixian ZHANG
The expressions of intensity distribution and coherent length of partially coherent light are obtained by using the cross spectral density function of the beam. Based on the expressions, the effects ofdifferent coherent parameters of light source and different turbulence intensity on the intensity distribution and coheThe expressions of intensity distribution and coherent length of partially coherent light are obtained by using the cross spectral density function of the beam. Based on the expressions, the effects ofdifferent coherent parameters of light source and different turbulence intensity on the intensity distribution and coherent length of partially coherent light in horizontal atmosphere are numerically simulated and compared with that of completely coherent light. The results show that, in the process of free space transmission, the light intensity distribution is mainly affected by the broadening caused by diffraction, and the larger the coherent parameter of light source is, the larger the coherent length of light beam is. While in the turbulent atmosphere, the larger the coherent parameters of light source is, the smaller the influence of the intensity of turbulent atmosphere on the intensity distribution and coherent length of light is. And with the increase of turbulence intensity and propagation distance, the beam broadening effect increases, and the coherent length of the beam decreases at the same time due to the turbulence superposition effect..
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 261 (2020)
Measurement of OH Reactivity of Diesel Vehicles Exhaust Based on LIF Method
Xiangsen SHEN, Shuoying LIU, Bin YUAN, Zibing YUAN, Huinan YANG, Jun CHEN, and Shengrong LOU
A direct measurement system of OH reactivity for vehicle exhaust measurement (LP-LIF-kOH) was established based on the principle of laser-induced fluorescence in this work, then the rotary drum test on the exhaust of typical diesel vehicles was carried out and the total OH reactivity of heavy diesel vehicles at differeA direct measurement system of OH reactivity for vehicle exhaust measurement (LP-LIF-kOH) was established based on the principle of laser-induced fluorescence in this work, then the rotary drum test on the exhaust of typical diesel vehicles was carried out and the total OH reactivity of heavy diesel vehicles at different emission levels was obtained. In the system, a pulsed UV laser is used to photolyze ozone to generate OH radical in a flow tube, and a pulse laser with a central wavelength of 308 nm is used to excite OH radicals. By using laser induced fluorescence technique, the decay of OH concentration caused by the reaction with the sampled reactive gases in the flow tube was measured and recorded, and the total reactivity of OH (kOH) with the sample gas can be derived by fitting the decay curve with an exponential function. In the closure experiment of the active organic compounds in the diesel vehicle exhaust gas, the measurement of the kOH of diesel cars in China emission standard III and China emission standard V was carried out. It is found that the value of diesel exhaust kOH decreases with the increase of China emission standard, and the kOH measured under cold start is greater than that measured under warm start for the same vehicle. The observed kOH is mainly contributed from NOx (55%), CO (2%), and the primary emission of VOCs (34%). A method of estimating the HC emission factor of diesel vehicles by using kOH is proposed to show the necessity of reactivity measurement in vehicle emission..
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 269 (2020)
Dynamic Release Correlation Between Extracellular Organic Components and Microcystins MC-LR Based on Three-Dimensional Fluorescence Spectroscopy
Qingjing ZHANG, Zhigang WANG, Saisai WANG, Dawei YAO, and Xiaofeng CHEN
By measuring the three-dimensional fluorescence spectra of extracellular organic matter (EOM) of microcystis aeruginosa sampled from Taihu Lake and cultured in laboratory during the growth period, the characteristics of three-dimensional fluorescence spectra components of EOM were obtained, and then the dynamic releaseBy measuring the three-dimensional fluorescence spectra of extracellular organic matter (EOM) of microcystis aeruginosa sampled from Taihu Lake and cultured in laboratory during the growth period, the characteristics of three-dimensional fluorescence spectra components of EOM were obtained, and then the dynamic release rules of the EOM of microcystis aeruginosa was studied, and the Pearson correlation analysis method was used to analysis the release correlation between these components and MC-LR in the process of growth. The results show that there are four strong fluorescent peaks in the three-dimensional fluorescence spectrum of EOM, namely A, C, S and T. Fluorescence peaks A and C belonges to the same kind of humus components, while the fluorescence peaks S and T belonges to the same kind of protein components. These two fluorescent components are mainly derived from the same process of growth and metabolism of microcystis aeruginosa, and have basically similar dynamic release laws. During the bloom of mcrocystis aeruginosa in Lake Taihu, the normalized intensity of the fluorescent peaks S, T, A, C of dEOM (dissolved extracellular organic matter)and fluorescent peak D of bEOM (bound extracellular organic matter)can basically reflect the ability of microcystis aeruginosa to release MC-LR in different physiological states and environments. And the normalized fluorescene intensity of the fluorescent peak S、T in dEOM can be selected as an important parameter for the future inversion of MC-LR..
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 285 (2020)
Pollution Characteristics of Secondary Water-Soluble Inorganic Ions in PM2.5 and Their Gaseous Precursors in Xiangtan, China
Xiaoyao MA, Zhenghui XIAO, Lizhi HE, and Yunjiang CAO
Atmospheric PM2.5 and the corresponding gaseous precursors (SO2、NO2) were simultaneously collected at two typical sampling sites in Xiangtan, central south China from December 3, 2013 to January 14, 2014, and then the concentrations of secondary water-soluble inorganic ions (SO2－4、NO－3 and NH+4) in PM2.5 were measured Atmospheric PM2.5 and the corresponding gaseous precursors (SO2、NO2) were simultaneously collected at two typical sampling sites in Xiangtan, central south China from December 3, 2013 to January 14, 2014, and then the concentrations of secondary water-soluble inorganic ions (SO2－4、NO－3 and NH+4) in PM2.5 were measured and analyzed by ion chromatography (IC) method. The sources, formation mechanism and influencingfactors of sulfate and nitrate in PM2.5 were discussed by analyzing the oxidation rates of sulfur (SOR) and nitrogen (NOR) at different air quality levels. The results show that, during the sampling time, the mass concentrations of PM2.5 and secondary water-soluble ions in Xiangtan City were 148.34 and 56.19 μg/m3, respectively. The concentrations of SO2－4、NO－3 and NH+4 accounted for 15.26%, 14.06% and 8.57% of PM2.5 concentration, respectively, and the total concentrations of SO2－4、NO－3 and NH+4 accounted for 37.88% of PM2.5 concentration. With increasing of PM2.5 concentration, the concentrations of secondary water-soluble inorganic ions and gaseous precursors (i.e. SO2 and NO2) increased correspondingly. The concentration of SO2－4、NO－3 and NH+4 in PM2.5 at severe pollution level were 1.93, 2.41 and 2.03 times higher than that at good pollution level. SO2－4 and NO－3 in PM2.5 at different air quality levels mostly existed in the form of NH4NO3 and (NH4)2SO4, while other sulfates and nitrates may also exist at both slightly and moderately polluted periods. The average values of SOR and NOR during sampling period at different pollution levels were above 0.1, indicating that sulfate and nitrate were mainly produced by secondary transformation of SO2 and NO2 in the atmosphere. The ratio of NO－3 to SO2－4 in PM2.5 was 0.89, and all thevalues for PM2.5 at different air quality levels were less than 1 (i.e. 0.78, 0.99, 0.82 and 0.97, respectively), indicating that the main source of the water-soluble ions in winter PM2.5 in Xiangtan city was coal combustion..
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 296 (2020)
Determination of Trace Elements in Three Cold Medicine Tablets by Laser-Induced Breakdown Spectroscopy
Yuanxia FU, Li WANG, Li XU, and Yu ZHOU
The trace elements of Compound paracetamol and amantadine dispersible tablets, Compound paracetamol and alkylamine tablets (Gankang) and Four seasons cold tablets have been analyzed by Laser-induced Breakdown Spectroscopy (LIBS). The laser with wavelength of 532 nm was focused on the surface of the medicine tablets to The trace elements of Compound paracetamol and amantadine dispersible tablets, Compound paracetamol and alkylamine tablets (Gankang) and Four seasons cold tablets have been analyzed by Laser-induced Breakdown Spectroscopy (LIBS). The laser with wavelength of 532 nm was focused on the surface of the medicine tablets to generate plasma, and then the spectra of the cold medicine tablets were detected through the collection of optical fiber and spectrometer, and the spectrograph of ICCD. The optimum spectra were obtained by optimizing the acquisition delay and gate width of ICCD. The results show that trace elements of Ca, Mg, Na have been identified in the Compound paracetamol and amantadine dispersible tablets and Four seasons cold tablets, and Ca, Mg have been identified in the Compound paracetamol and alkylamine tablets (Gankang). The electron temperature of plasma were calculated from the intensity of emission spectrum, the excitation energy, statistical weight of the upper levels and the corresponding transition probability of emission spectra. Then the time evolution characteristics of the electron temperature of the plasma induced by laser for the three kinds of cold tablets were studied..
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 305 (2020)
Design of Ovality Measurement System of High Speed Wire Rod Based on Machine Vision
Wei KONG, Chunhong LIU, Haibin WU, Xinbing CHEN, Junchen GE, Zongbao GAO, and Hongxu Chen
A non-contact measurement system of wire ellipticity, where three cameras are used, is designed in the laboratory environment, which can be used to simulate the high-speed wire ellipticity monitoring in the industrial field. First, the real-time images of wire rod are collected by using bilateral telecentric lens, collA non-contact measurement system of wire ellipticity, where three cameras are used, is designed in the laboratory environment, which can be used to simulate the high-speed wire ellipticity monitoring in the industrial field. First, the real-time images of wire rod are collected by using bilateral telecentric lens, collimating light source and high-speed area array CCD industrial camera, and the camera is calibrated and distortion-corrected . Then the real-time images collected by the three cameras are preprocessed in turn, and a method of adaptive Ψ-value motion blur image restoration is proposed. Finally, the wire diameter measured by three cameras is calculated by the points on two lines detected by Hough transform, and then the wire ellipticity is calculated by using the diameter. The results show that the measurement accuracy of the system under the laboratory conditions can meet the accuracy required in the actual industrial production , andit is expected to be put into use in the high-speed wire production line..
Journal of Atmospheric and Environmental Optics
- Publication Date: Jan. 01, 1900
- Vol. 15, Issue 4, 314 (2020)
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