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Characteristics of observed trace gaseous pollutants in the Yangtze Delta

Science China Earth Sciences 2003年第4期46卷 397-404页

作者：王会祥唐孝炎王木林颜鹏王韬邵可声曾立民杜惠芳陈立民 Center of Environmental Sciences and State Key Laboratory of Environmental Simulation and Pollution Control Peking University Chinese Academy of Meteorological Sciences Hong Kong Polytechnic University Hong Kong China Department of Environmental Science and Engineering Fudan University

Six stations in the Yangtze Delta were set up to measure minute-average ground-level concentrations of NO, NOx, SO2, CO and O3 from May, 1999 to Oct., 2000 continually. The per-centage of total valid data of all sites was over 80%. The observed data were of adequate regional representation. The individual mean value of NO, NOx, SO2 and CO in the six selected sites was much higher than that of background level. Strong seasonal variations of observed data in the sites were expounded with peaks in winter. These showed that the air had been contaminated by anthropogenic pollutants. The highest monthly mixing ratios of O3 were found in May or June, and an ozone episode in September.

关键词： Yangtze Delta, gaseous pollutants, tropospheric ozone.

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Effect of Rare Earths on Fractionation and Transformation of Soil Available Nitrogen

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Journal of Rare Earths 2003年第5期21卷 582-586页

作者：丁士明梁涛张自立孙琴张朝生 Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Science Department of Soil & Agrichemistry Anhui Agricultural University State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Department of Geography and Environmental Change Institute National University of Ireland

The effect of rare earths (RE) on fractionation and transformation of available nitrogen in a yellow cinnamon soil was studied with soil cultivation. The results show that under the dry condition, when the extraneous RE are added to the soil, both concentrations of soil ammonium N and hydrolysable N increase, and the concentrations of soil nitric N decrease. The concentrations of soil available N increase with the increase of RE concentrations in soils when the RE concentrations are low, but it decreases with the increase of high RE concentrations in soils. The NOEC (no observed effect concentration) of the extraneous RE to available N in the soils is 443.8 mg·kg -1 . Under the inundated condition, low RE concentrations in soil has no significant effect on soil ammonium N and hydrolysable N. However, when the soil RE concentrations are high, both of them decrease with the increase of RE concentrations. The NOEC of the extraneous RE to soil ammonium N and hydrolysable N are 171.2 and 256.9 mg·kg -1 , respectively.

关键词： pedology nitrogen transformation yellow cinnamon soil rare earths

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Influence of humic substance in solids on CODMn of the Yellow River

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Surface Mining - Braunkohle and Other Minerals 2003年第1期55卷 132-135页

作者： Meng, Li-Hong Xia, Xing-Hui State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

Experiments were carried out to study the influence of humic substance in solids (Loess soil) on CODMn in the Yellow River. Several significant results were abtained from the study: (1) The total CODMn of water sample including liquid and solid phases increased significantly with the increase of solid content;The CODMn of liquid phase of water sample under pre-treatment with acid (LPWSPC) also increased significantly with the increase of solid content while that without pre-treatment did not increased significantly. (2) With the increasing of solid content, the total BOD 5 of water sample increased much slower than the total COD Mn and the CODMn of LPWSPC. (3) The humic substances with the content of 0.76% in solids (Loess soil) contributed greatly to the total CODMn of water sample. When the solid contents were 7.5 g/L and 15.0 g/L, the humic substances in solids accounted for 15.9 % and 21.7 % of the total CODMn of water sample, respectively. (4) When solid contents were 7.5 g/L and 15.0 g/L, fulvic acid, one of the main compositions of humic substance contributed to 23.6% and 50.6% of the CODMn of LPWSPC, respectively. Since the fulvic acid can hardly be biologically oxidized under natural conditions, the CODMn of LPWSPC in water quality monitoring exaggerates the oxygen-consuming organic contamination of the Yellow River.

关键词： Chemical oxygen demand

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Lead Removal from Aqueous Solutions Using Novel Gel Adsorbent Synthesized from Natural Condensed Tannin

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Chinese Journal of Chemical Engineering 2003年第4期11卷 426-430页

作者：占新民赵璇 AKANE Miyazaki YOSHIO Nakano State Key Joint Laboratory on Environment Simulation and Pollution Control Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Section of Environmental Technology Institute of Nuclear Energy Technology Tsinghua University Beijing 100084China Department of Environmental Chemistry and Engineering Interdisciplinary Graduate School of Science and Engineering Tokyo Institute of Technology Nagatsuta 4259 Midori-ku Yokohama 226-8502 Japan

Lead has caused serious environmental pollution due to its toxicity, accumulation in food chains and persistence in nature. In this paper, removal of lead from aqueous solutions is investigated using a novel gel adsorbent synthesized from natural condensed tannin. The novel adsorbent performs in aqueous solutions as a weak base with valid basic groups of 1.2mmol·g-1 tannin gel particles and therefore results in the elevation of pH value of aqueous solutions. Even when initial pH is 3.6, final pH at equilibrium can climb up to 6.5 that is above the pH value for Pb(OH)2 precipitation formation and then lead can be removed from wastewater by this so-called surface precipitation. The adsorption isotherm can be expressed by the Langmuir equation and the maximum capacity for adsorption of Pb is up to 92 mg·g-1 (based on dry adsorbent) when initial pH value is 3.6. Hence, the adsorbent does offer favorable properties in lead removal with respect to its high adsorption capacity at low initial pH value, which is advantageous to lead removal from acidic wastewater. A model is put forward to describe the individual adsorption phenomenon of the tannin gel adsorbent.

关键词： condensed tannin lead removal surface precipitation tannin gel adsorbent

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ADSORPTION OF BENZOIC ACID AND P-NITROBENZOIC ACID ON A NEW HYPERCROSSLINKED PHENOL GROUP PST ADSORBENT

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Chinese Journal of Reactive Polymers 2003年第1期12卷 59-69页

作者： ZHANG Gencheng LIUFuqiang FEI Zhenghao LI Aimin ZHANG Quanxing Institute of Applied Chemistry and Environmental Engineering Department of ChemistryYancheng Teachers CollegeYancheng 224002China State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing UniversityNanjing 210093China

A comparison of the adsorption of benzoic acid and p-nitrobenzoic acid on the new hypercrosslinked polymeric adsorbent AM-1, with that by macroporous Amberlite XAD-4, including the equilibrium adsorption isotherms, the dynamic adsorption behaviors through column and the adsorption thermodynamics were studied. Results show that Freundlich equation gives a fitting adsorption isotherm. The specific surface of AM-1 is only 67% of that of Amberlite XAD-4, but the adsorption capacities on AM-1 are much higher about 125%~166% than that on Amberlite XAD-4, which is contributed to the micropore mechanism and polarity. The negative values of the adsorption enthalpy are indicative of an exothermic process. Enthalpy and free energy changes of adsorption both manifest a physic-sorption process. The negative values of the adsorption entropy indicate that the adsorption is well consistent with the restricted mobilities and the configurations of the adsorbed benzoic acid molecules on the surface of studied adsorbents with superficial heterogeneity. Both adsorbents were used in mini-column experiments for adsorbing benzoic acid expecting to elucidate the higher breakthrough adsorption capacity of the new hypercrosslinked polymeric adsorbent AM-1 as compared with that of Amberlite XAD-4.

关键词： Hypercrosslinked phenol group Pst adsorbent Adsorption of benzoic acid p-Nitrobenzoic acid Thermodynamic properties

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Growth feature of biomass of Lemna aequinoctialis and Spirodela polyrrhiza in medium with nutrient character of wastewater

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Surface Mining - Braunkohle and Other Minerals 2003年第1期55卷 59-64页

作者： Chong, Yun-Xiao Hu, Hong-Ying Qian, Yi Environmental Simulation and Pollution Control State Key Join Laboratory Department of Environmental Science and Engineering Tsinghua University 100084 Beijing China

Duckweeds have an important potential in nutrient recovery from wastewater because of their rapid multiplication and high protein content in biomass. The growth rate of duckweed biomass has a direct relationship with nutrient removal and recovery. With laboratory experiments of batch culture and continuous culture, the growth curves of two duckweed species, Lemna aequinoctialis and Spirodela polyrrhiza, cultivated in different media were gotten and fitted by Logistic model. The effect of nitrogen on growth of duckweed was evaluated. Experimental results indicated that the growth curve had characteristic of sigmoidal shape and the growth rate had density-dependent characteristic. Results of statistical analysis demonstrated that Logistic model is suitable to describe the growth of single duckweed specie. The maximal growth rate from regression in medium with ammonia nitrogen was lower than those in medium with nitrate nitrogen. The maximal growth rate of Lemna aequinoctialis was higher than Spirodela polyrrhiza The paper also discussed the application of Logistic model in harvesting of duckweed biomass from wastewater.

关键词： Biomass

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Regular pattern of non-point source pollutants losses in Luxi watershed

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Surface Mining - Braunkohle and Other Minerals 2003年第1期55卷 108-112页

作者： Hu, Yuan-An Cheng, Sheng-Tong Jia, Hai-Feng Environmental Simulation and Pollution Control State Key Point Joint Laboratory Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

The losses of non-point pollutant combined with natural rainfall events were monitored at outlets of Luxi watershed and several field plots with different land use. The paper probes characteristics of the sediment and chemical losses during a single rainfall-runoff process. The impact of preceding precipitation is also discussed. The results of field experiments show that the concentration of SS in runoff dropped off obviously with the increase of antecedent rainfall. The observed data were 265.6, 145.8, 124.2mg/L respectively with precipitation of 15, 115, 161 mm in preceding 5 days. Compared to the losses of SS, nutrients and COD were not changed greatly by the preceding rainfalls. The fluctuations of pollutant concentration were less than 15%. The results from plots suggested that land use play an important role in pollutant losses. The following is the list ordered according to concentration of pollutant in runoff, from the highest to the lowest: Dry land, residential area, grassland,woodland and paddy land. Vegetation cover is effective on the reduction of soil erosion and sediment loss. About 80% SS could be cut down when the coverage changed from 50% to 90%. Losses of TN were mainly determined by the TN concentration in *** ratios of TN concentration in runoff to that in soil were 2.75%, 2.79%, 2.42% respectively for the land use of dry land, grassland and woodland. Augment of vegetation overage contributed to increment of N losses, including NO3- -N and NH1 +-N.

关键词： Watersheds

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Biogenic Isoprene Emission Mechanism from ^(13)CO_2 Exposure Experiments

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Chinese Chemical Letters 2002年第9期13卷 897-900页

作者： Min SHAO state Joint key laboratory of environmental simulation and pollution control, Center for environmental Sciences, Peking University, Beijing 100871 State Joint Key Laboratory of Environmental Simulation and Pollution Control Center for Environmental Sciences Peking University Beijing 100871 China

Biogenic isoprene emissions have been believed to be from only photosynthesis processes in plant. However nocturnal isoprene emission from pine is detected. And by feeding 13CO2 to plants, it is found that both photos... 详细信息

关键词： Emissions volatile organic compounds (VOCs) 13C labeling isoprene.

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Eco-environmental water requirement for wetlands in Huang-Huai-Hai Area, China

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自然科学进展(英文版) 2002年第11期12卷 841-848页

作者： CUI Baoshan YANG Zhifeng Institute of Environmental Sciences Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875 China Institute of Environmental Sciences Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875 China Institute of Water Sciences Beijing Normal University Key Laboratory for Water and Sediment

Based on the related literature and the analysis of the relationship between wetland ecosystem and hydroperiod, the estimating and classifying methods of eco-environmental water requirement for wetlands are established. The data collected from Huang-Huai-Hai Area are from the electronic map (1∶250000) of China National Topographical Database of 1997 and the historical statistics since the *** results indicate that the minimum eco-environmental water requirement for wetlands is 16.98×109 m3 and the optimal one is 38.38×109 m3 in the studied area. For the five wetland nature reserves covered in the area, the values are 1.47×109 m3 and 3.31×109 m3 respectively. The comparisons of the mentioned minimum water requirement with the status water use, which is 17.05×109 m3 for wetland ecosystem (1997 as the status year), suggest that the water use has not met the minimum eco-environmental water requirement in the Haihe and Huanghe Basins of the studied area. However, the status water use guarantees and exceeds the minimum eco-environmental water requirement in the Shandong Peninsula and the Huaihe Basin. Based on the eco-environmental programming and water resource planning of the studied area, the study establishes the water requirement of the year of 2010, 2030, 2050, when the eco-environmental water requirement for wetlands is 18.30×109 m3, 21.64×109 m3 and 26.76×109 m3, respectively.

关键词： eco-environmental water requirement wetlands Huang-Huai-Hai Area

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Quantification of acetone emission from pine plants

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Science China Chemistry 2002年第5期45卷 532-540页

作者：邵敏 Jürgen Wildt State Joint Key Laboratory of Environmental Simulation and Pollution Control Center for Environmental Sciences Peking University Beijing 100871 China

Acetone emission from pine plants (pinus sylvestris) is measured by continuously stirred tank reactor. Under a constant light intensity, acetone emission rates increase exponentially with leaf temperature. When leaf temperature is kept constant, acetone emission increases with light intensity. And acetone emission in darkness is also detected. Acetone emitted from pine is quickly labeled by 13C when the plants are exposed to air with 630 mg/m3 13CO2. However, no more than 20% of acetone is 13C labeled. Acetone emission from pine may be due to both leaf temperature- controlled process and light intensity-controlled process. Based on these understandings, an algorithm is used to describe the short term acetone emission rates from pine.

关键词： biogenic emission, carbonyl compound, 13C labeling, simulation.

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