Wang M.,Peking University |
Zeng L.,Peking University |
Lu S.,Peking University |
Shao M.,Peking University |
And 7 more authors.
Analytical Methods | Year: 2014
An automatic gas chromatograph system equipped with a mass spectrometer and a flame ionization detector (GC-MS/FID) was developed for online measurements of volatile organic compounds (VOCs) in the atmosphere. This system consisted of a custom-built cryogen-free cooling device that can create an ultra-low temperature of -165°C, a two-channel sampling and pre-concentration system, and a commercial GC-MS/FID. One channel in the sampling and pre-concentration system was designated to trap C2-C5 hydrocarbons, whereas the other was designed to trap other VOC species. The newly developed GC-MS/FID system was then employed to measure VOCs in ambient air, and its observation data were compared with those from three well-established techniques, including an offline GC-MS/FID coupled with canister sampling, a proton transfer reaction-mass spectrometer (PTR-MS), and an online gas chromatograph system equipped with an FID and a photo ionization detector (GC-FID/PID). The online and offline GC-MS/FID measurements for alkanes, acetylene, C2-C3 alkenes, C6-C8 aromatics, and halocarbons showed good agreement. In addition, the online GC-MS/FID measurements for C6-C9 aromatics, acetone, and methacrolein + methylvinylketone (MACR + MVK) agreed well with the PTR-MS observations. Mixing ratios of C2-C7 alkanes, C3-C5 alkenes, and C6-C8 aromatics also showed good agreement between the online GC-MS/FID and GC-FID/PID techniques. These inter-comparison results demonstrated the accuracy of online GC-MS/FID measurements for C2-C12 NMHCs, C3-C4 carbonyls, and halocarbons. © 2014 The Royal Society of Chemistry.
Qu J.,Chinese Academy of Sciences |
Qu J.,Lanzhou University |
Zeng J.,Chinese Academy of Sciences |
Li Y.,Lanzhou University |
And 7 more authors.
Energy Policy | Year: 2013
This study assessed household CO2 emissions (related to the consumption of necessary and luxury goods and services) of peasants and herdsmen households in arid-alpine regions in Gansu, Qinghai and Ningxia provinces, China. We also explored whether agriculture types, family income and family size have played any role in household CO2 emissions. In order to address these issues, we: (i) developed assessment indicators for household emissions; (ii) conducted semi-structured questionnaire household surveys; and (iii) employed input-output analysis (IOA). The results showed that, the average household CO2 emission per capita is 1.43 tons (t) CO2; the proportion of subsistence emissions (related to the consumption of necessary goods and services) accounts for 93.24%, whereas luxury emissions (generated due to consumption of specific goods and services that are consumed only when household income improves) only account for 6.76%t. Moreover, household CO2 emissions increase with family income and family size, but per capita emissions are inversely related to family size. The highest average household emissions were found in the alpine agricultural and pastoral region (6.18t CO2), followed by the irrigated agricultural region (6.07t CO2) and the rain-fed agricultural region (5.34t CO2). In consideration of insignificant amount of household emissions from these poor and vulnerable groups of the society, this study suggests to follow the principle of fairness while making energy conservation, emission reduction and adaptation policies. © 2013 Elsevier Ltd.
Fan Q.,Sun Yat Sen University |
Shen C.,Sun Yat Sen University |
Wang X.,Sun Yat Sen University |
Li Y.,Guangzhou Research Institute of Environmental Protection |
And 4 more authors.
Asia-Pacific Journal of Atmospheric Sciences | Year: 2013
A strong dust-storm (23-25 April, 2009) occurred in the provinces of Inner Mongolia, Gansu, and Shanxi, North China. Cities along the storm path (from north to south: Xi'ning, Lanzhou, Chengdu, Changsha, and Guangzhou) all experienced a sharp increase in particle matter (PM10) concentration. This is the first case that an Asian dust storm hit Guangzhou in Southern China. The impacts of dust storm on the characteristics of PM were investigated using samples collected in Guangzhou during 27-29 April, 2009. In addition, the mass concentration and chemical composition during a normal non-dust period (12-14 May, 2009) were compared with those in dust period. The results show that the concentration of PM10 during the dust episode (0.231 mg m -3) was twice higher than that in the non-dust episode (0.103 mg m-3). Chemical analysis showed that concentrations of metal elements, enrichment factors of metal elements, and soluble ions during the dust episode were very different from those of non-dust. The total concentration of metal elements content in PM10 was 53.5 μg m-3 in the dust episode, which is about two times higher than that in non-dust episode (28.5 μg m-3). Increases in concentrations of Na, Ti, Zn, Cu, and Cr ranged from zero to 100% during the dust episode. However, the enrichment factors in non-dust episode were higher than that in dust-storm period, indicating that the above five chemicals originated mainly from local sources in Guangzhou. The concentrations of K, Mg, Al, Fe, Mn, V, and Co increased by over 100% in the dust episode, indicating their origins of remote sources. In the dust period, some water-soluble ions increased in PM10, but the main components in PM10 were SO4 -, NO3 - and NH4 +. At last, we assessed the sources of dusts by analyzing synoptic situation and back trajectories of air mass in Guangzhou, and demonstrated that the main source of the dust storm was from Mongolia. © 2013 The Korean Meteorological Society and Springer.
Yu L.-S.,Guangzhou Research Institute of Environmental Protection |
Yu L.-S.,Sun Yat Sen University |
Fu Y.-F.,Sun Yat Sen University |
Yu H.-Y.,Guangzhou Research Institute of Environmental Protection |
Li Z.-Q.,Guangzhou Research Institute of Environmental Protection
Chinese Journal of Applied Ecology | Year: 2011
In order to understand the landscape pattern gradient dynamics and desakota features in rapid urbanization area, this paper took the rapidly urbanizing Panyu District of Guangzhou City as a case, and analyzed its land use and land cover data, based on four Landsat TM images from 1990 to 2008. With the combination of gradient analysis and landscape pattern analysis, and by using the landscape indices in both class and landscape scales, the spatial dynamics and desakota feature of this rapidly urbanizing district were quantified. In the study district, there was a significant change in the landscape pattern, and a typical desakota feature presented along buffer gradient zones. Urban landscape increased and expanded annually, accompanied with serious fragmentation of agricultural landscape. The indices patch density, contagion, and landscape diversity, etc., changed regularly in the urbanization gradient, and the peak of landscape indices appeared in the gradient zone of 4-6 km away from the urban center. The landscape patterns at time series also reflected the differences among the dynamics in different gradient zones. The landscape pattern in desakota region was characterized by complex patch shape, high landscape diversity and fragmentation, and remarkable landscape dynamics. The peaks of landscape indices spread from the urban center to border areas, and desakota region was expanding gradually. The general trend of spatiotemporal dynamics in desakota region and its driving forces were discussed, which could be benefit to the regional land use policy-making and sustainable development planning.
Liu J.,Sun Yat Sen University |
Liu J.,Guangzhou Research Institute of Environmental Protection |
Zhong Y.,Sun Yat Sen University |
Wang L.,Sun Yat Sen University |
Jia X.,Sun Yat Sen University
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2010
Nitrogen removal was compared for anammox bacteria immobilized in absorbent materials (active carbon, china ring, china ball, corallites vesuvianite and packing fibre) and entrapping materials (beads of sodium alginate (SA), polyvinyl alcohol(PVA), PVA-SA and PVA-SA-active carbon). The results showed that anammox activities of bacteria immobilized in most of the materials were the same as those of the original anammox bacteria. However, the nitrogen removal ratio of anammox bacteria immobilized in absorbent materials was higher than that of entrapping materials. Anammox bacteria immobilized in activated carbon showed the highest nitrogen removal ratio in the experiment, reaching nearly 1.32 times higher than the control on the 3rd day. In this study, nitrogen removal ratio was continuously monitored in a 1 L column reactor for 15 d. Anammox activity after immobilization in activated carbon was 3.5 times higher than the control in the 6th recycle, which showed that anammox immobilized in activated carbon has the potential to remove nitrogen effectively and steadily for a long time.
Huang Q.,Jinan University |
Han H.,Jinan University |
Zhang Z.Y.,Guangzhou Research Institute of Environmental Protection |
Wang B.G.,Jinan University |
Zhang C.L.,Jinan University
Advanced Materials Research | Year: 2014
Tunnel source is an important emission source in urban microenvironment, and the influence of emission pollutants from tunnel source to air quality in surrounding area could not be ignored. In this study the monitoring data in the entrance and the exit of the tunnel was used to calculate the emission amount from tunnel source. Then the methodology to establish the tunnel source emission inventory with a high temporal resolution was discussed in this paper. This research would provide basis for the establishment of the emission inventory in urban microenvironment, and provide a more realistic emissions inventory to Air Quality Model. © (2014) Trans Tech Publications, Switzerland.
Zhang J.-E.,South China Agricultural University |
Liu J.-L.,Guangzhou Research Institute of Environmental Protection |
Ouyang Y.,St. Johns River Water Management District |
Liao B.-W.,Chinese Academy of Forestry |
Zhao B.-L.,South China Agricultural University
Ecological Engineering | Year: 2010
Mangrove wetlands are important in the removal of nutrients, heavy metals, and organic pollutants from wastewater within estuarine systems due to the presence of oxidized and reduced conditions, periodic flooding by incoming and outgoing tides, and high clay and organic matter content. This study investigated the removal efficiency of nutrients and heavy metals from wastewater by the mangrove Sonneratia apetala Buch-Ham in a simulated wetland. Eight different treatments, namely, three concentration levels of wastewaters, with and without planting of the mangrove species, and one control (with salted water) each for both with and without planting of the mangrove species, were employed in this study. Results showed that the amounts of total mangrove biomass from different treatments were in the following order: PL-TW (planted with ten times higher-than-normal wastewater concentration) > PL-FW (planted with five times higher-than-normal wastewater concentration) > PL-SW (planted with normal wastewater concentration) > PL-NW (planted with no wastewater), whereas the magnitude of the heavy metal contents in the biomass was in the following order: Cu > Pb > Cd > Zn. Very good linear correlations existed between the biomass and the nutrients or heavy metals. The Sonneratia apetala Buch-Ham species had its own selectivity for uptake of heavy metals regardless of the initial heavy metal contents and was more effective in the removal of nutrients than heavy metals. Our study suggested that mangrove wetlands with Sonneratia apetala Buch-Ham species had great potential for the removal of nutrients and heavy metals in coastal areas. © 2010 Elsevier B.V. All rights reserved.
Zhang Y.,CAS Guangzhou Institute of Geochemistry |
Wang X.,CAS Guangzhou Institute of Geochemistry |
Li G.,CAS Guangzhou Institute of Geochemistry |
Li G.,University of Chinese Academy of Sciences |
And 14 more authors.
Atmospheric Environment | Year: 2015
Motor vehicles contribute primarily and secondarily to air quality problems due to fine particle (PM2.5) and ozone (O3) pollution in China's megacities. Characterizing vehicle emission with the rapid change of vehicle numbers and fleet compositions is vital for both bottom-up emission survey and top-down source apportioning. To obtain emission factors (EFs) of PM2.5, carbonaceous aerosols and trace gases for road vehicles, in urban Guangzhou we conducted a field campaign in 2014 in the Zhujiang Tunnel, a heavily burdened tunnel with about 40,000 motor vehicles passing through each of its two separated bores per day. PM2.5 and volatile organic compounds (VOCs) were sampled for offline analysis while trace gases including SO2, NOx and CO were measured online and in situ. An eddy covariance system with an integrated 3-D sonic anemometer was also adopted to measure CO2 and winds inside the tunnel. We recorded an average fleet composition of 61% light-duty gasoline vehicles (LDVs) + 12% heavy-duty diesel vehicles (HDVs) + 27% liquefied petroleum gas vehicles (LPGVs), and EFs of 82.7 ± 28.3, 19.3 ± 4.7 and 13.3 ± 3.3 mg veh-1 km-1, respectively, for PM2.5, organic carbon (OC) and elemental carbon (EC). These EFs were respectively 23.4%, 18.3% and 72.3% lower when compared to that measured in the same tunnel in 2004. EFs of PM2.5, OC and EC were higher at night time (148 ± 126, 29 ± 24 and 21 ± 18 mg veh-1 km-1, respectively) due to significantly elevated fractions of HDVs in the traffic fleets. An average ratio of OC to EC 1.45 from this tunnel study was much higher than that of ~0.5 in previous tunnel studies. The EFs of SO2, NOx, CO, CO2 and NMHCs for road traffic were also obtained from our tunnel tests, and they were 20.7 ± 2.9, (1.29 ± 0.2)E+03, (3.10 ± 0.68)E+03, (3.90 ± 0.49)E+05, and 448 ± 39 mg veh-1 km-1, respectively. © 2015 Elsevier Ltd.
Yang C.,South China University of Technology |
Liu X.-Q.,South China University of Technology |
Huang B.-C.,South China University of Technology |
Wu Y.-M.,Guangzhou Research Institute of Environmental Protection
Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica | Year: 2014
A series of ZrO2/MWCNTs were prepared, using ZrO(NO3)2•2H2O as a precursor, by the surface modification of multiwalled carbon nanotubes (MWCNTs). Manganese oxides were supported on the ZrO2/ MWCNTs to prepare MnOx/ZrO2/MWCNTs catalysts. The effect of zirconium on the selective catalytic reduction (SCR) activity of the catalysts was investigated. Furthermore, the structural properties of the catalysts were comprehensively characterized by a suite of analytical methods. The results show that the addition of zirconium improved the SCR activity of the MnOx/MWCNTs significantly and the catalyst with 30% Zr loading was found to have the highest activity. X- ray powder diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), and N2adsorption-desorption results revealed that the modification of zirconium could enhance the dispersion of MnOx on the support as well as enhance the interaction between the metal oxides and the MWCNTs. Additionally, zirconium could also increase the specific surface area, the total pore volume, and the average pore size of the catalysts. Moreover, from the results of X-ray photoelectron spectroscopy (XPS), H2 temperature-programmed reduction (H2-TPR), and temperature-programmed desorption of NH3 (NH3- TPD), zirconium increased the atomic concentration of the chemisorbed oxygen on the catalysts surface and promoted the conversion of Mn3+ to Mn4+. Therefore, the surface-active sites increased and the redox ability of the catalysts improved. Additionally, the amount and strength of acid on catalyst surface increased. These factors are the main reason for the MnOx/ZrO2/MWCNTs catalysts having better low-temperature SCR activity. © Editorial office of Acta Physico-Chimica Sinica.
Huang D.-Y.,CAS Guangzhou Institute of Geochemistry |
Huang D.-Y.,Guangdong Institute of Eco environmental and Soil Sciences |
Xu Y.-G.,CAS Guangzhou Institute of Geochemistry |
Zhou B.,Guangzhou Research Institute of Environmental Protection |
And 2 more authors.
Environmental Monitoring and Assessment | Year: 2010
With the aim of understanding the seasonal distribution of deposition fluxes of nitrogen (N) and sulfur (S) in South China, a main acid deposition region in China, precipitation samples were collected and analyzed from Guangzhou area, between March 2005 and February 2006. The estimated wet deposition of N (including ammonium nitrogen (NH4-N) and nitrate nitrogen (NO3-N)) and S (sulfate sulfur (SO4-S)) during the monitoring period were 40.47 kg N ha-1 and 65.29 kg S ha -1, respectively. The average deposition of NH4-N was ∼1.5 times of the NO3-N deposition, suggesting that the reduced and oxidized N depositions were comparable in the study area. The S and N depositions in the rainy season were greater than those in the dry season, showing great seasonal variation, which was consistent with both the distribution of precipitation and the period of fertilizer application for agriculture. The N and S wet deposition fluxes in Guangzhou were greater than those in Beijing and Zhengzhou, located in the northern China, but comparable to the level of Chongqing, located in the southwestern China, another major acid deposition region. The atmospheric N and S depositions in these cities from north to south were affected by both intensive agricultural and industrial activities. © 2009 Springer Science+Business Media B.V.