Journal of Atmospheric and Environmental Optics
Co-Editors-in-Chief
Wenqing Liu

Jan. 01, 1900
  • Vol. 10 Issue 1 1 (2015)
  • Qian FENG, Bin ZOU, and Wei ZHAO

    With the assumption that nonspherical mineral dust aerosols are considered to be a mixture of randomly oriented spheroidal particles with particle size and shape distributions, the scattering properties of nonspherical mineral dust aerosols at visible wavelength (0.47 μm) are theoretically simulated based on the T-matrix method and improved geometric optics method (IGOM). The corresponding results related to laboratory measurements and equal volume spherical particles are also presented for comparison. The results indicate that it is feasible to simulate the scattering properties of nonspherical dust aerosols by considering dust particles to be a mixture of randomly oriented spheroidal particles with particle size and shape distributions, and the differences between equal volume spherical particles and spheroidal particles are obvious for single scattering phase matrix (especially single scattering phase function) when compared with the differences associated with single-scattering albedo, asymmetry factor and extinction efficiency. Moreover, by comparing the radiative properties of dust aerosols at the visible wavelength for spheroid and sphere particle shape assumption, it is found that the effect of particle shape on the single scattering properties cannot be neglected in simulating the radiative properties of nonspherical dust aerosols.

    Jan. 01, 1900
  • Vol. 10 Issue 1 1 (2015)
  • Hongchao SHEN, Xiaoquan SONG, Zhaobin SUN, Xiaopeng WANG, Guangyao DAI, and Songhua WU

    Cloud height and cloud amount are very essential for the meteorological service in the automatic and quantitative measurement and effective data analysis from different device is of great significance. A cloud measurement system intergating two different modules for cloud height and cloud amount have been developed, so that cloud height and cloud amount can be obtained at the same time and place. And then, combined with profile data of cloud height and cloud two-dimensional distribution in the sky, a preliminary analysis of data fusion for cloud amount, cloud height and cloud classification is made. Through the data fusion, sky images of the whole sky imager can be used to identify the fog haze and improve the cloud height recognition accuracy. Moreover, the analysis of the whole sky image can obtain total cloud amount. With the data of cloud height, the spatial distribution of the cloud in the sky can be estimated and more accurate cloud classification can be achieved. In fact, data fusion analysis of cloud height and cloud amount is the development direction of the meteorological service.

    Jan. 01, 1900
  • Vol. 10 Issue 1 11 (2015)
  • Longlong YUN, Tianshu ZHANG, Fan LU, Dexia WU, Shijie SHENG, Yihuai LU, and Jianguo LIU

    The concentrations of PM2.5, carbonaceous aerosols, O3, NOx, SO2 were measured from a haze event in Wuxi City, Jiangsu, China from Dec. 21th to Dec. 26th, 2013. Aerosol extinction coefficient and depolarization ratio were measured by micro-pulse polarization lidar. Characteristics of air pollutants in haze days were analysed. The haze event last for 3.4 days and fine particles were the main pollutants. Hourly average mass concentration of PM2.5 was 131.04 μg·m-3, and 183.75 μg·m-3 in haze days which was 2.98 times higher than in normal days. Total carbon (TC), which was strongly correlated (correlation coefficients=0.790) with PM2.5, accounted for 24.18% of the mass concentration of PM2.5. In haze days, the ratio of TC to PM2.5 was 16.65%, lower than that in normal days (34.38%). This suggested that secondary inorganic particles might have a fast increase in haze days, which led to a high concentration of PM2.5. The concentration of O3, affected greatly by solar radiation, showed less variation both in haze days and normal days. The volume fraction of NOx and SO2 in haze days was 1.66 which was 1.68 times higher than in normal days, respectively. The increase concentration of SO2 was not only related to local accumulation but also can be affected by sulfur-rich particles from external transmission; the sulfur-rich particles might inhibit the heterogeneous reaction of SO2.

    Jan. 01, 1900
  • Vol. 10 Issue 1 22 (2015)
  • Lixia KE, Chengyin SHEN, Chaoqun HUANG, Yan LU, Lei XIA, Xiaojing CHEN, and Yannan CHU

    To investigate the characteristics of volatile organic compounds from thunbergii, latifoliu and aurantiacu, the independently developed proton transfer reaction mass spectrometer was applied to detect the compounds. Mass spectra of the compounds from thunbergii, latifoliu and aurantiacu at three different voltages of drift tube (250 V, 320 V and 461 V) were obtained. The results showed that m/z of the characteristic product ions of thunbergii were 171, 105, 91, 87, 73 and 69, m/z of ions of latifoliu were 120, 105, 91, 77, 73 and 69, and m/z of ions of aurantiacu were 137, 73, 69 and 51. Through comparative analysis, it was found that there were several common characteristic product ions, but the product ions and its intensity from different species of Osmanthus fragrans presented differences. The experimental results show that the instrument can achieve rapid detection and characteristic product ions can be used to identify different species of Osmanthus fragrans. Proton transfer reaction mass spectrometry has been applied in monitoring volatile organic compounds in environmental and the experimental results have certain reference to environmental gas monitoring.

    Jan. 01, 1900
  • Vol. 10 Issue 1 31 (2015)
  • Kang WANG, Yujun ZHANG, Sheng LI, Kun YOU, and Wenqing LIU

    Due to atmospheric instability, various noise and sky background radiation of photoelectric detector, the semiconductor laser ceilometer APD detector receives the backscatter signal with low signal noise ratio (SNR) which cannot be directly used for parameter inversion of cloud. So for this characteristic of the backward scattering signal, a data collection and processing scheme of the semiconductor laser ceilometer based on FPGA was proposed. This scheme can achieve the DC blocking of backward scattering signal, high-speed data acquisition, cumulative average, and at the same time it can complete complex sequential control, such as the whole system transmitting and receiving, data storage and upload. Compared with the experimental verification, the scheme can obviously increase the SNR of the backward scattering signal, and achieve the parameters inversion of atmospheric cloud.

    Jan. 01, 1900
  • Vol. 10 Issue 1 39 (2015)
  • Haibin WU, and Lingli KONG

    The importance of controlling the cracking furnace temperature is presented. The method of monitoring the furnace tube temperature based on the colorimetric temperature measurement, as well as the CCD photoelectric properties to the requirement of exposure are introduced. The calculating method of temperature T is obtained by comparing several calibrating temperature and calculating temperature. And the feasibility of the method is proved through the experiment.

    Jan. 01, 1900
  • Vol. 10 Issue 1 46 (2015)
  • Ruihuan JING, Jinji MA, and Chao WANG

    Earth-observing satellites have provided satellite image datasets for urban-scale air quality monitoring. Aerosol optical depths (AOD) at 1 km resolution is retrieved from MODIS on Terra and Aqua Satellite by using the improved algorithm. The 1 km AOD data are validated by using AOD measurements of AERONET station in the period from September 2013 to January 2014. Then the validated 1 km AOD data are compared with ground-based PM2.5 mass concentration and PM10 mass concentration in Nanjing metropolitan area respectively. Then these models have been amended by fine aerosol optical depths and the meteorological factors. The revised model of Nanjing metropolitan area is y=136.78+9.16x1-0.36x2-3.98x3, with R2=0.79. By applying the model, it is confirmed that the aerosol optical depths can be used to evaluate the quality of urban air.

    Jan. 01, 1900
  • Vol. 10 Issue 1 51 (2015)
  • Xuzhou HOU, Weining YI, Yanli QIAO, Honglian HUANG, Wenyu CUI, Lili DU, and Chuan CHEN

    Atmospheric correction is important for land remote sensing application. In data processing over multi-spectral remote sensing land image, an atmospheric correction method is presented. The method is based on 6S radiative transfer code and an empirical method of decreasing adjacency effect. To evaluate this correction procedure, FLAASH (another mature atmospheric correction model) is processed as a comparison. Results suggest that the quality of corrected image is improved apparently, the accuracy of the method and FLAASH remain about 10%.

    Jan. 01, 1900
  • Vol. 10 Issue 1 63 (2015)
  • Dahai ZHANG, Nanjing ZHAO, Gaofang YIN, Mingjun MA, Li HU, Chaoyi SHI, Xinxin DONG, Yin WANG, Yang YU, Deshuo MENG, Xiaoya YU, Jiuyue WANG, and Ruifang YANG

    For continuous automatic, fast and high sensitive analysis of heavy metal in water by laser-induced breakdown spectroscopy technique (LIBS), the sample solution was enriched onto graphite sheet and heated by electromagnetic induction heating technology. Finally, the rapid heating and enrichment of the sample was achieved. In addition, the dry judgment method based on the cooling slope were investigated. In the example of a set temperature 140℃ and timing 2 s, the rise time was measured as 30 s from room temperature to 140℃ and the temperature error range was -5~+3℃. The completion status of enrichment was also accurately determined on the basis of the cooling slope. The results show that the rapid heating and accurate drying judgment can be effectively achieved by the use of electromagnetic induction heating technology combined with the judgment method of enrichment completion based on the cooling slope.

    Jan. 01, 1900
  • Vol. 10 Issue 1 69 (2015)
  • Mingwu CHEN, and Haibin WU

    In the aspect of infrared detector, the operating wavelength of the traditional infrared CCD is 0.4~1.1 μm. Affected by the cut-off wavelength, the error of infrared CCD is very large in industrial low temperature measurement. The operating wavelength of uncooled infrared focal plane array (IRFPA) camera is generally between 8~14 μm, of which temperature measurement accuracy can reach to 0.01℃ under the optimum working environment. The UL01011, most commonly used as the core photo detector in the uncooled focal plane uncooled micro-bolometer array infrared camera, was used as the experimental photoelectric detector. Experimental results showed that this method can achieve better results in practice.

    Jan. 01, 1900
  • Vol. 10 Issue 1 87 (2015)
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