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Xing B.,CAS Institute of Automation | Yang Y.,Kunming University of Science and Technology | Yang Y.,Yunnan Metallurgy Group Corporation | Qian L.,Yunnan Environmental Monitoring Center
Asian Journal of Chemistry | Year: 2016

A vortex-assisted liquid-phase microextraction was applied for the extraction of trace amounts of platinum(II) prior to flame atomic absorption spectrometry detection in the water sample. Ammonium pyrolysine dithiocarbamate was used as the chelating agent and noctanol as an extractant. The fine droplets of n-octanol were made and dispersed as a cloud in the aqueous sample with the help of vortex mixing. Different parameters such as the pH, the amount of ammonium pyrolysine dithiocarbamate, the composition and volume of the extraction agent and vortex time were studied to get the optimum results. Under optimal conditions, the low limit of detection is 2.0 μg mL-1. Recoveries of platinum spiked into tap water samples were in the range of 85.0∼91.5 %. The relative standard deviations is 2.12 % (n = 6). The correlation coefficient of the calibration curve is 0.9977. The proposed method was successfully applied for the determination of platinum in the real tap water samples. Source


Shi J.,Kunming University of Science and Technology | Ding X.,Kunming University of Science and Technology | Zhou Y.,Kunming University of Science and Technology | You R.,Kunming University of Science and Technology | And 8 more authors.
Frontiers of Environmental Science and Engineering | Year: 2016

A sampling campaign including summer, autumn and winter of 2014 and spring of 2015 was accomplished to obtain the characteristic of chemical components in PM2.5 at three sites of Kunming, a plateau city in South-west China. Nine kinds of water-soluble inorganic ions (WSI), organic and element carbon (OC and EC) in PM2.5 were analyzed by ion chromatography and thermal optical reflectance method, respectively. Results showed that the average concentrations of total WSI, OC and EC were 22.85±10.95 µg·m-3, 17.83±9.57 µg·m-3 and 5.11±4.29 µg·m-3, respectively. They totally accounted for 53.0% of PM2.5. Secondary organic and inorganic aerosols (SOA and SIA) were also assessed by the minimum ratio of OC/EC, nitrogen and sulfur oxidation ratios. The annual average concentrations of SOA and SIA totally accounted for 28.3% of the PM2.5 concentration. The low proportion suggested the primary emission was the main source of PM2.5 in Kunming. However, secondary pollution in the plateau city should also not be ignorable, due to the appropriate temperature and strong solar radiation, which can promote the atmospheric photochemical reactions. [Figure not available: see fulltext.] © 2016, Higher Education Press and Springer-Verlag Berlin Heidelberg. Source


Bi L.-M.,Kunming University of Science and Technology | Hao J.-M.,Kunming University of Science and Technology | Hao J.-M.,Tsinghua University | Ning P.,Kunming University of Science and Technology | And 3 more authors.
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2015

A set of PM2.5 samples from three sampling sites belonging to the regional air monitoring networks of Kunming were collected during April 2013 to January 2014, and 16selected PAHs were analyzed by GC-MS. Average concentrations of PM2.5-bound PAHs from the industrial area (Jinding Mountain), traffic area (Dongfeng Tung Road) and clean area (Xishan Forest Park) were 40.67, 22.64, 22.07 ng/m3. High atmospheric pressure and the input of air mass originated from the Qujing area were the cause of rising PAHs concentration in Kunming. Result of health risk assessment of PAHs showed, the concentration of BaPeq at Jinding Mountain, Dongfeng Tung Road and Xishan Forest Park was 6.28, 4.00, 2.94 ng/m3, respectively, exceeded the national ambient air quality standard (2.5 ng/m3) in China. The PAHs in industrial area and traffic area were mainly influenced by vehicle emission (50.80% and 40.20%), followed by coal combustion (35.55% and 39.23%), biomass combustion (7.30% and 7.98%); clean area was effected by vehicle emission (81.84%) and biomass combustion (9.73%). ©, 2015, Chinese Society for Environmental Sciences. All right reserved. Source


Li A.,Yunnan University | Li A.,Yunnan Environmental Monitoring Center | Guo Y.,Dianchi Lake Ecology Institute of Kunming City | He F.,Dianchi Lake Ecology Institute of Kunming City | Yuan R.,Yunnan University of Finance and Economics
Advanced Materials Research | Year: 2012

There are few indicator systems available for monitoring and assessing the environmental quality of large-scale regions. We constructed an indicator system for integrated assessment of the environmental quality of the Dianchi Basin. First, the definition of regional environmental quality is determined by both the supply of materials and energy in the region and the extent to which the region is polluted. Second, the indicator categories used for assessment mainly comprise vegetation biomass and the concentrations of various pollutants. Third, owing to spatial heterogeneity of a region, evaluation of the regional environment first requires division into sub-regions, each of which should be relatively homogeneous with regard to physical conditions (e. g. marine and terrestrial) and appearance (e. g. vegetation cover). Finally, the mathematical models for assessing regional environmental quality can be built according to the relationships between the various indicators, the sub-regions and regional environmental quality. The indicator system built using this approach can reflect environmental changes over time and identifies reasons for environmental variation. © (2012) Trans Tech Publications, Switzerland. Source


Ding Y.,Kunming University of Science and Technology | Huang Y.,Yunnan Environmental Monitoring Center | Zhao T.,Kunming University of Science and Technology | Cai Q.,Kunming University of Science and Technology | And 4 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2014

A method for the determination of five representative organic UV filters: ethylhexyl methoxycinnamate (EHMC), benzophenone-3 (BP-3), 4-methylbenzylidene camphor (4-MBC), octocrylene (OC), homosalate (HMS) in water was investigated. The method was based on derivatization, solid phase extraction (SPE), followed by determination with gas chromatography-mass spectrometry (GC-MS). The variables involved in the derivatization of BP-3 and HMS were optimized, and SPE conditions were studied. For derivatization, 100 μL, N,O-bis (trimethylsilyl) trifluoroacetamide (BSTFA) was used as derivatization reagent and reacted with BP-3 and HMS at 100 °C for 100 min. For SPE, the pH value of water sample was adjusted to 3-5. The Oasis HLB cartridges were employed and the solution of ethyl acetate and dichloromethane (1:1, v/v) was used as the eluting solvent, and good recoveries of the target compounds were obtained. The limits of detection (LODs) and the limits of quantification (LOQs) for the five target compounds in water samples were 0. 5-1. 2 ng/L and 1. 4-4. 0 ng/L, respectively. The recoveries of spiked water samples were 87. 85%-102. 34% with good repeatability and reproducibility (RSD<5°%, n = 3) for all the target compounds. Finally, the validated method was applied to analysis the representative UV filters in water samples collected from a wastewater treatment plant in Kunming city of Yunnan province. Source

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