矿化垃圾基本理化性状剖面变化特征研究

矿化垃圾能否作为农业资源被重新利用,除应考虑有效植物营养物质的含量与是否存在有害物质外,还取决于其基本理化性状。对城市生活垃圾填埋场中经填埋6年、8年、10年后得到的矿化垃圾基本物化性状变化特征进行分析,结果表明:矿化垃圾的土粒密度显著小于对照土壤,交换性盐基总量、CEC显著大于对照土壤,pH值和对照土壤基本相当;表层(0~50 cm)矿化垃圾的土粒密度、CEC、交换性盐基总量、pH值的变化幅度依次大于中层(50~100 cm)和下层(100~150 cm);矿化垃圾的理化性状在填埋8~10年后总体趋于稳定。从植物生长的环境角度看,填埋8~10年后的矿化垃圾可以开采后作为植物生长基质、土壤改良剂等农业资源化利用。     

Gene expression signatures in PCB-exposed Slovak children in relation to their environmental exposures and socio-physical characteristics

Environmental Science and Pollution Research - Our previous gene expression studies in a PCB-exposed cohort of young children in Slovakia revealed that early-life exposures to PCBs and other...     

玻璃抛光废渣理化特性研究

为处置和利用一种玻璃抛光废渣,用XRF、ICP、XRD、SEM、灰熔点炉、粒度分析和浸出毒性等实验手段对其化学成分、浸出毒性、颗粒径和比表面积等理化性质进行了系统研究。结果表明,玻璃抛光废渣虽然主体是Si、Al、Fe、K、Na、Ca和Mg的硅酸盐,但含一定量的Pb、Ba、Cr、Mn、Zn、V、Cu和As等重金属元素,80%的粒径小于15μm,平均粒径为6.31μm,比表面积为480 m2/g,是一种细粉状浸出毒性较高的有害固废;烧结能有效地固封和固溶其中的重金属,可作为控制其污染和处置利用的有效措施。     

Horticultural oils: possible alternatives to chemical pesticides and insecticides

Environmental Science and Pollution Research - The farmers and agrochemical industries lack science-based knowledge about sustainable utilization of pesticides and insecticides. The investigation...     

Influence of plants on the chemical extractability and biodegradability of 2,4-dichlorophenol in soil

This study investigated the fate and behaviour of [UL-(14)C] 2,4-dichlorophenol (DCP) in planted (Lolium perenne L.) and unplanted soils over 57 days. Extractability of [UL-(14)C] 2,4-DCP associated activity was measured using calcium chloride (CaCl(2)), acetonitrile-water and dichloromethane (DCM) extractions. Biodegradability of [UL-(14)C] 2,4-DCP associated activity was assessed through measurement of (14)CO(2) production by a degrader inoculum (Burkholderia sp.). Although extractability and mineralisation of [UL-(14)C] 2,4-DCP associated activity decreased significantly in both planted and unplanted soils, plants appeared to enhance the sequestration process. After 57 days, in unplanted soil, 27% of the remaining [UL-(14)C] 2,4-DCP associated activity was mineralised by Burkholderia sp., and 13%, 48%, and 38% of (14)C-activity were extracted by CaCl(2), acetonitrile-water and DCM, respectively. However, after 57 days, in planted soils, only 10% of the [UL-(14)C] 2,4-DCP associated activity was available for mineralisation, whilst extractability was reduced to 2% by CaCl(2), 17% by acetonitrile-water and 11% by DCM. This may be due to the effect of plants on soil moisture conditions, which leads to modification of the soil structure and trapping of the compound. However, the influence of plants on soil biological and chemical properties may also play a role in the ageing process.     

Toxicity to freshwater organisms from oils and oil spill chemical treatments in laboratory microcosms

Toxicity and temporal changes in toxicity of freshwater-marsh-microcosms containing South Louisiana Crude (SLC) or diesel fuel and treated with a cleaner or dispersant, were investigated using Chironomus tentans, Daphnia pulex, and Oryzias latipes. Bioassays used microcosm water (for D. pulex and O. latipes) or soil slurry (for C. tentans) taken 1,7, 31, and 186 days after treatment. SLC was less toxic than diesel, chemical additives enhanced oil toxicity, the dispersant was more toxic than the cleaner, and toxicities were greatly reduced by day 186. Toxicities were higher in the bioassay with the benthic species than in those with the two water-column species. A separate experiment showed that C. tentans' sensitivity was intermediate to that of Tubifex tubifex and Hyallela azteca. Freshwater organisms, especially benthic invertebrates, thus appear seriously effected by oil under the worst-case-scenario of our microcosms. Moreover, the cleaner and dispersant tested were poor response options under those conditions.     

Toxicity and biodegradability of sulfonamides and products of their photocatalytic degradation in aqueous solutions

The photocatalytic degradation of sulfacetamide, sulfathiazole, sulfamethoxazole and sulfadiazine in water solutions during their illumination of UV radiation (lambda(max) 366 nm) with TiO2 catalyst was examined. The growth-inhibition effect of sulfonamides and intermediate products theirs photodegradation was investigated in aqueous solution with the green alga Chlorella vulgaris. The biodegradability of the investigated compounds was determined in the illuminated solutions and is expressed as Biochemical Oxygen Demand. It was found that all of the investigated sulfonamides in the initial solutions were resistant to biodegradation and were toxic relative to C. vulgaris. The toxicity (EC50 values) relative to C. vulgaris increased in the following order sulfacetamide, sulfathiazole, sulfamethoxazole, sulfadiazine. All of the investigated sulfonamides undergo photocatalytic degradation. The toxicity of intermediate products of the sulfonamides degradation was significantly lower than the toxicity of sulfonamides in the initial solutions and was dependent on illumination time and degradation rate. The intermediate products of photocatalysis in contrast to the initial sulfonamides, might be mineralized using biological methods.     

Comparison of the physical and chemical characteristics of fine road dust at different urban sites

The size distribution and chemical components of a fine fraction (<2.5 μm) of road dust collected at urban sites in Korea (Gwangju) and Mongolia (Ulaanbaatar) where distinct urban characteristics exist were measured. A clear bimodal size distribution was observed for the resuspended fine road dust at the urban sites in Korea. The first mode peaked at 100–110 nm, and the second peak was observed at 435–570 nm. Ultrafine mode (~30 nm) was found for the fine road dust at the Mongolia site, which was significantly affected by residential coal/biomass burning. The contribution of the water-soluble ions to the fine road dust was higher at the sites in Mongolia (15.8–16.8%) than at those in Korea (1.2–4.8%). Sulfate and chloride were the most dominant ionic species for the fine road dust in Mongolia. As (arsenic) was also much higher for the Mongolian road dust than the others. The sulfate, chloride, and As mainly come from coal burning activity, suggesting that coal and biomass combustion in Mongolia during the heating season should affect the size and chemical components of the fine road dust. Cu (copper) and Zn (zinc), carbonaceous particles (organic carbon [OC] and elemental carbon [EC]) increased at sites in Korea, suggesting that the fine road dust at these sites was significantly affected by the high volume of traffic (engine emission and brake/tire wear). Our results suggest that chemical profiles for road dust specific to certain sites should be applied to more accurately apportion road dust source contributing to the ambient particulate matter.

Implications: Size and chemical characteristics of fine road dust at sites having distinct urban characteristics were examined. Residential coal and biomass burning and traffic affected physiochemical properties of the fine road dust. Different road dust profiles at different sites should be needed to determine the ambient PM2.5 sources more accurately.     

垃圾焚烧飞灰物理化学性质的实验研究

应用激光粒度粒形分析仪、灰熔融性测定仪、原子吸收光谱仪和XRD等仪器手段对国内2种垃圾焚烧飞灰的密度、颗粒特性、熔点、成分和晶相结构等物理化学性质进行了详细的研究。研究发现，2种灰样颗粒直径的数量积分分布非常接近，其中基本没有超过40 μm的颗粒。由于垃圾焚烧飞灰在化学成分上存在的差异导致了其熔点有很大的不同。此外，XRD结果显示不同来源的飞灰其晶相结构存在较大的差别，这可能与垃圾的来源和焚烧工艺以及烟气处理方法有关。实验结果为飞灰无害化低温烧结工艺的选择和运行参数的制定提供了依据。     

On the relation between the size and chemical composition of aerosol particles and their optical properties

The light scattering and absorption coefficients of fine atmospheric aerosol particles were recorded in Hungary under rural conditions in 1998–1999 by an integrating nephelometer and particle soot absorption photometer, respectively. In some cases optical properties in the fine size range were compared to those in the coarse particles. Results obtained indicate, as expected, that fine particles control the scattering and absorption caused by the aerosol. In 1999 the size distribution of aerosol particles was also monitored by means of an electric low pressure impactor (ELPI). This makes it possible the study of the relationship between the number, surface and mass concentration in the size range of 0.1–1.0 μm and the optical characteristics by also considering the chemical composition of the particles.     

The ecotoxicology of vegetable versus mineral based lubricating oils: 3. Coral fertilization and adult corals

Biodegradable vegetable-derived lubricants (VDL) might be less toxic to marine organisms than mineral-derived oils (MDL) due to the absence of high molecular weight aromatics, but this remains largely untested. In this laboratory study, adult corals and coral gametes were exposed to various concentrations of a two-stroke VDL-1A and a corresponding MDL to determine which lubricant type was more toxic to each life stage. In the fertilization experiment, gametes from the scleractinian coral Acropora microphthalma were exposed to water-accommodated fractions (WAF) of VDL-1A and MDL for four hours. The MDL and VDL-1A WAFs inhibited normal fertilization of the corals at 200 microg l(-1) total hydrocarbon content (THC) and 150 microg l(-1) THC respectively. Disturbance of a stable coral-dinoflagellate symbiosis is regarded as a valid measure of sub-lethal stress in adult corals. The state of the symbiosis in branchlets of adult colonies of Acropora formosa was monitored using indicators such as dinoflagellate expulsion and dark-adapted photosystem II yields of dinoflagellate (using pulse amplitude modulation fluorescence). An effect on symbiosis was measurable following 48 h exposure to the lubricants at concentrations of 190 microg l(-1) and 37 microg l(-1) THC for the MDL and VDL-1A respectively. GC/MS revealed that the main constituent of the VDL-1A WAF was the compound coumarin, added by the manufacturer to improve odour. The fragrance containing coumarin was removed from the lubricant formulation and the toxicity towards adult corals re-examined. The coumarin-free VDL-2 exhibited significantly less toxicity towards the adult corals than all of the other oil types tested, with the only measurable effect being a slight but significant drop in photosynthetic efficiency at 280 microg l(-1).     

Comparison of photocatalytic degradation of dyes in relation to their structure

The photocatalytic degradation of a series of six acid dyes (Direct Red 80, Direct Red 81, Direct Red 23, Direct Violet 51, Direct Yellow 27, and Direct Yellow 50) has been tested compared in terms of color removal, mineralization, and toxicity (Lactuca sativa L. test) after photocatalysis on immobilized titanium dioxide. The dyes were examined at their natural pH and after hydrolysis at pH 12. Results show that hydrolysis decreases strongly the efficiency of color removal, that full mineralization takes much longer reaction time than color removal, and that toxicity is only very partially reduced. Some structural parameters, related to the structure and the topology of the dye molecules, could be correlated with the apparent color removal rates at natural pH.     

An investigation on the physical,chemical and ecotoxicological characteristics of particulate matter emitted from light-duty vehicles

Particulate matter (PM) emitted from three light-duty vehicles was studied in terms of its physicochemical and ecotoxicological character using Microtox^® bioassay tests. A diesel vehicle equipped with an oxidation catalyst emitted PM which consisted of carbon species at over 97%. PM from a diesel vehicle with a particle filter (DPF) consisted of almost equal amounts of carbon species and ions, while a gasoline vehicle emitted PM consisting of ～90% carbon and ～10% ions. Both the DPF and the gasoline vehicles produced a distinct nucleation mode at 120 km/h. The PM emitted from the DPF and the gasoline vehicles was less ecotoxic than that of conventional diesel, but not in direct proportion to the emission levels of the different vehicles. These results indicate that PM emission reductions are not equally translated into ecotoxicity reductions, implying some deficiencies on the actual environmental impact of emission control technologies and regulations.     

Anaerobic biodegradability and methanogenic toxicity of key constituents in copper chemical mechanical planarization effluents of the semiconductor industry

Copper chemical mechanical planarization (CMP) effluents can account for 30-40% of the water discharge in semiconductor manufacturing. CMP effluents contain high concentrations of soluble copper and a complex mixture of organic constituents. The aim of this study is to perform a preliminary assessment of the treatability of CMP effluents in anaerobic sulfidogenic bioreactors inoculated with anaerobic granular sludge by testing individual compounds expected in the CMP effluents. Of all the compounds tested (copper (II), benzotriazoles, polyethylene glycol (M(n) 300), polyethylene glycol (M(n) 860) monooleate, perfluoro-1-octane sulfonate, citric acid, oxalic acid and isopropanol) only copper was found to be inhibitory to methanogenic activity at the concentrations tested. Most of the organic compounds tested were biodegradable with the exception of perfluoro-1-octane sulfonate and benzotriazoles under sulfate reducing conditions and with the exception of the same compounds as well as Triton X-100 under methanogenic conditions. The susceptibility of key components in CMP effluents to anaerobic biodegradation combined with their low microbial inhibition suggest that CMP effluents should be amenable to biological treatment in sulfate reducing bioreactors.     

Loss of carbofuran from rice paddy water: chemical and physical factors.

The loss of carbofuran was studied from rice paddy water treated with a granular formulation of the insecticide, and from ponds filled with drainage from the paddy. The average half-life (t 1/2) for carbofuran loss was 57 hr. Controlled experiments indicated that pH was the predominating factor governing carbofuran loss from water in the environment studied. The loss due to hydrolysis was over 700 times more rapid at pH (t 1/2 = 1.2 hr.) than at pH (t 1/2 = 864 hr.) in buffered deionized water. The average pH of the rice paddy was 8, but diurnal fluctuations of 7 to 9.5 are common in similar environments. Impurities in the water, sunlight, and temperature influence the rate of carbofuran loss but not nearly so much as pH. There was no evidence for significant loss due to evaporation or oxidation. The results have important implications for the duration of the insecticide's activity and the effect on fish within or downstream from treated paddies.     

Aerosol concentrations observed at Mt. Haruna,Japan, in relation to long-range transport of Asian mineral dust aerosols

As a part of the effort to understand the structure of long-range transported aerosol plumes and local pollution, aerosol observations monitored the mass concentrations and number-size distributions during the period August 2006 to July 2009 near the top of Mt. Haruna (1365 m), an isolated mountain in the Kanto Plain in Japan. The mass concentrations observed at Mt. Haruna and plain sites showed a seasonal variation with a maximum in spring and summer, respectively. The spring peaks in aerosols at Mt. Haruna were probably caused by long-range transport of mineral dust and anthropogenic particles from the Asian continent. The summer peaks at the plain sites was attributed to local pollution from the Tokyo metropolitan area. Three examples of 2007 Asian dust events were investigated to show that aerosols may be dispersed in a complicated three-dimensional structure and that delayed arrivals of the dust plumes at plain sites compared to Mt. Haruna were not a rare case. Because of the boundary layer being stable at night, the dust layer was advected eastward without the vertical mixing before sunrise. This study suggests that after thermal convection activated by sunlight during daytime Asian dust transported in the free troposphere may be brought down into the atmospheric boundary layer, increasing the dust concentration there.     

Production of a refined biooil derived by fast pyrolysis of chicken manure with chemical and physical characteristics close to those of fossil fuels

The chemical and physical properties of raw biooils prevent their direct use in combustion engines. We processed raw pyrolytic biooil derived from chicken manure to yield a colorless refined biooil with diesel qualities. Chemical characterization of the refined biooil involved elemental and several spectroscopic analyses. The physical measurements employed were viscosity, density and heat of combustion. The elemental composition (% wt/wt) of the refined biooil was 82.7 % C, 15.3 % H, 0.2 % N and 1.8 % O, no S. Its viscosity was 0.006 Pa.s and a heat of combustion of 43 MJ kg^?1. The refined biooil fraction contains n-alkanes, ranging from n-C₁₄ to n-C₂₇, alkenes varying from C_10:1 to C_22:1, and long-chain alcohols. The refined biooil makes a good diesel fuel due to its chemical and physical properties.     

Production of a refined biooil derived by fast pyrolysis of chicken manure with chemical and physical characteristics close to those of fossil fuels

The chemical and physical properties of raw biooils prevent their direct use in combustion engines. We processed raw pyrolytic biooil derived from chicken manure to yield a colorless refined biooil with diesel qualities. Chemical characterization of the refined biooil involved elemental and several spectroscopic analyses. The physical measurements employed were viscosity, density and heat of combustion. The elemental composition (% wt/wt) of the refined biooil was 82.7 % C, 15.3 % H, 0.2 % N and 1.8 % O, no S. Its viscosity was 0.006 Pa.s and a heat of combustion of 43 MJ kg(-1). The refined biooil fraction contains n-alkanes, ranging from n-C(14) to n-C(27), alkenes varying from C(10:1) to C(22:1), and long-chain alcohols. The refined biooil makes a good diesel fuel due to its chemical and physical properties.