珠江三角洲非道路移动源排放清单开发

根据收集到的珠江三角洲非道路移动源活动水平数据,采用适合各类非道路移动源污染物排放量的估算方法和排放因子,建立了珠江三角洲地区2006年非道路移动源排放清单.结果表明,珠江三角洲地区2006年非道路移动源排放SO2为6.52×104t,NOx为1.24×105t,VOC为4.54×103t,CO为2.67×104t,PM10为4.51×103t.其中船舶为最大的SO2、NOx、CO和PM10排放贡献源,分别占非道路移动源排放总量的96.4%、73.8%、39.4%和50.5%.在船舶排放源中,SO2、NOx、VOC、CO和PM10排放量的89.8%、81.8%、77.3%、79.5%和81.7%来自货轮和散装干货船.非道路移动源已成为该地区第三大SO2和NOx排放贡献源,分别占珠江三角洲大气污染源SO2和NOx排放总量的8.6%和13.5%.     

燃烧过程中煤氮热迁移特性研究进展

燃烧过程中煤氮的热迁移特性决定着NOx的生成与最终排放量,并对控制和治理燃煤过程中NOx污染具有重要指导意义。将煤氮的热迁移过程分为挥发分氮及焦炭氮2个不同热迁移路径进行讨论,归纳了在燃烧过程中挥发分氮及焦炭氮热迁移的特性及相关影响因素。最后提出了"定量解析煤氮热迁移过程"这一国际学术难题的研究突破口。     

Seasonal variation and factors influencing perchlorate in water,snow, soil and corns in Northeastern China

Seasonal variation and influencing factors of perchlorate in snow, surface soil, rain, surface water, groundwater and corn were studied. Seven hundreds and seventy samples were collected in different periods in Harbin and its vicinity, China. Perchlorate concentrations were analyzed by ion chromatography–electrospray mass spectrometry. Results indicate that fireworks and firecrackers display from the Spring Festival to the Lantern Festival (February 2, 2011–February 17, 2011) can result in the occurrence of perchlorate in surface soil and snow. Perchlorate distribution is affected by wind direction in winter. Melting snow which contained perchlorate can dissolve perchlorate in surface soil, and then perchlorate can percolate into groundwater so that perchlorate concentrations in groundwater increased in spring. Perchlorate concentrations in groundwater and surface water decrease after rainy season in summer. Groundwater samples collected in the floodplain areas of the Songhua River and the Ashi River contained higher perchlorate concentrations than that far away with the rivers. The corns have the ability to accumulate perchlorate.     

青藏高原纳木错湖水主要化学离子的时空变化特征

为揭示青藏高原纳木错湖水化学离子的时空变化特征、来源以及主要控制因子,于2006～2010年连续定点(30°47.27’N,90°58.53’E,4 718 m a.s.l.)采集近岸表层湖水样品;于2009年8月采集湖心区剖面样品;于2010年10月采集湖心区剖面样品及表层湖水样品;对其主要化学离子进行分析.结果表明,纳木错湖水中主要阳离子为Na+,主要阴离子为HCO3-.绝大多数离子浓度在季风期较高(6～9月),而非季风期尤其是封冻期(1～4月)偏低;Ca2+浓度的变化则相反,即封冻期较高,而非封冻期较低且变化较小.对垂直剖面湖水分析表明,在湖水垂直结构稳定的非季风期(如10月),除Ca2+浓度随深度无显著变化外,其他离子浓度随深度增加而增大.纳木错湖水主要离子来源于入湖河水的贡献;影响离子时空变化的因素包括蒸发、降水、pH值等,其中蒸发是最主要的影响因素,它造成湖水Na+浓度不断升高而Ca2+浓度降低.     

Evaluating aeration techniques for decreasing phosphorus export from grasslands receiving manure

Because surface-applied manures can contribute to phosphorus (P) in runoff, we examined mechanical aeration of grasslands for reducing P transport by increasing infiltration of rainfall and binding of P with soil minerals. The effects of three aeration treatments and a control (aeration with cores, continuous-furrow "no-till" disk aeration perpendicular to the slope, slit aeration with tines, and no aeration treatment) on the export of total suspended solids, total Kjeldahl P (TKP), total dissolved P (TDP), dissolved reactive P (DRP), and bioavailable P (BAP) in runoff from grasslands with three manure treatments (broiler litter, dairy slurry, and no manure) were examined before and after simulated compaction by cattle. Plots (0.75 x 2 m) were established on a Cecil soil series with mixed tall fescue (Festuca arundinacea Schreb.)-bermudagrass [Cynodon dactylon (L.) Pers.] vegetation on 8 to 12% slopes. Manures were applied at a target rate of 30 kg P ha(-1), and simulated rainfall was applied at a rate of 85 mm h(-1). Although the impact of aeration type on P export varied before and after simulated compaction, overall results indicated that core aeration has the greatest potential for reducing P losses. Export of TKP was reduced by 55%, TDP by 62%, DRP by 61%, total BAP by 54%, and dissolved BAP by 57% on core-aerated plots with applied broiler litter as compared with the control (p < 0.05). Core and no-till disk aeration also showed potential for reducing P export from applied dairy slurry (p < 0.10). Given that Cecil soil is common in pastures receiving broiler litter in the Southern Piedmont, our results indicate that pairing core aeration of these pastures with litter application could have a widespread impact on surface water quality.     

活性污泥膨胀上浮的原因分析与对策

污泥膨胀是活性污泥法污水处理的一个难题，尤其在处理高负荷的石化污水中。文章分析了引起污泥膨胀、上浮的主要原因，对引起污泥上浮的因素进行了探讨，提出了控制污泥膨胀、上浮的几种对策。     

Fly ash reinforced thermoplastic vulcanizates obtained from waste tire powder

Novel thermoplastic composites made from two major industrial and consumer wastes, fly ash and waste tire powder, have been developed. The effect of increasing fly ash loadings on performance characteristics such as tensile strength, thermal, dynamic mechanical and magnetic properties has been investigated. The morphology of the blends shows that fly ash particles have more affinity and adhesion towards the rubbery phase when compared to the plastic phase. The fracture surface of the composites shows extensive debonding of fly ash particles. Thermal analysis of the composites shows a progressive increase in activation energy with increase in fly ash loadings. Additionally, morphological studies of the ash residue after 90% thermal degradation shows extensive changes occurring in both the polymer and filler phases. The processing ability of the thermoplastics has been carried out in a Monsanto processability testing machine as a function of shear rate and temperature. Shear thinning behavior, typical of particulate polymer systems, has been observed irrespective of the testing temperatures. Magnetic properties and percolation behavior of the composites have also been evaluated.     

Removing arsenic from groundwater in Cambodia using high performance iron adsorbent

In Cambodia, groundwater has been contaminated with arsenic, and purification of the water is an urgent issue. From 2010 to 2012, an international collaborative project between Japan and Cambodia for developing arsenic-removing technology from well water was conducted and supported by the foundation of New Energy and Industrial Technology Development Organization, Japan. Quality of well water was surveyed in Kandal, Prey Veng, and Kampong Cham Provinces, and a monitoring trial of the arsenic removal equipment using our patented amorphous iron (hydr)oxide adsorbent was performed. Of the 37 wells surveyed, arsenic concentration of 24 exceeded the Cambodian guideline value (50 μg L^?1), and those of 27 exceeded the WHO guideline for drinking water (10 μg L^?1). Levels of arsenic were extremely high in some wells (>1,000–6,000 μg L^?1), suggesting that arsenic pollution of groundwater is serious in these areas. Based on the survey results, 16 arsenic removal equipments were installed in six schools, three temples, two health centers, four private houses, and one commune office. Over 10 months of monitoring, the average arsenic concentrations of the treated water were between 0 and 10 μg L^?1 at four locations, 10–50 μg L^?1 at eight locations, and >50 μg L^?1 at four locations. The arsenic removal rate ranged in 83.1–99.7 %, with an average of 93.8 %, indicating that the arsenic removal equipment greatly lower the risk of arsenic exposure to the residents. Results of the field trial showed that As concentration of the treated water could be reduced to <10 µg L^?1 by managing the As removal equipment properly, suggesting that the amorphous iron (hydr)oxide adsorbent has high adsorbing capacity for As not only in the laboratory environment but also in the field condition. This is one of the succeeding As removal techniques that could reduce As concentration of water below the WHO guideline value for As in situ.     

Spatial and temporal patterns of soil erosion in the Tibetan Plateau from 1984 to 2013北大核心CSCD

Soil erosion has a critical effect on ecological security and socioeconomics, which may deteriorate ecosystem services and common human well-being. The revised universal soil loss equation (RUSLE) was applied to assess soil erosion from 1984 to 2013 in the Tibetan Plateau and analyzed the temporal and spatial variation of soil erosion intensity. Furthermore, the temporal and spatial variation rates of soil erosion were explored across different ecosystems. The results indicated that the annual soil erosion fuctuated in the Tibetan Plateau, the soil erosion intensity decreased from south to north, and the most serious soil erosion was mainly distributed in the southern Tibetan Plateau (Xigaze and Changdu regions, Lhasa, and north of the Shannan region). The soil erosion intensity was higher in shrub, alpine meadow, and sparse vegetation ecosystems. The highest soil erosion was found in alpine meadow (2.17 × 1010 t), followed by alpine grassland (1.59 × 1010 t) and sparse vegetation (1.30 × 1010 t) ecosystems. Meanwhile, although the most serious soil erosion intensity was found in the regions of 3 000-4 000 m altitude, the soil erosion was mainly observed in the regions of 4 000-5 000 m altitude. In the three most recent decades, annual soil erosion decreased at a rate of-1.78 × 108 t/a. Additionally, soil erosion mainly increased in south of the Qiangtang Plateau and in the periphery of the Qaidam basin. Decreased soil erosion was mainly found along the Hengduan Mountains, central Himalayas. Although the increased annual normalized difference vegetation index (NDVI) had positive effects for soil protection, changes in soil erosion was mainly controlled by the change of annual precipitation. Thus, the fragility of ecological systems and increased rainfall erosivity accounted for the obviously increased soil erosion in the alpine grassland ecosystem (1.19 × 10 t/a). However, increased ecosystem stability and decreased rainfall erosivity contributed to the decreased soil erosion in forest and shrub ecosystems, by-0.77 × 10 t/a and-1.65 × 10 t/a, respectively. The slightly decreased rainfall erosivity accounted for a decrease of soil erosion in the sparse vegetation ecosystem (-0.44 × 10 t/a). Meanwhile, soil erosion has decreased in the alpine meadow ecosystem over the past 30 years, which may owing to the relatively higher NDVI that neutralized the increase of rainfall erosivity to some extent. This study revealed serious soil erosion regions and ecosystems in the Tibetan Plateau and explored possible reasons for variations in soil erosion in different ecosystems, which may provide a scientific reference for soil erosion conservation and control in the near future. © 2018 Science Press. All rights reserved.     

城市可持续发展能力及其影响因素的实证

应用DEA方法构建了一个综合评价城市可持续发展能力的指标——资源与环境效率系数,利用除拉萨以外的全国30个直辖市、省会城市、自治区首府2005-2008年的面板数据,计算了城市资源与环境效率系数,并对资源与环境效率的影响因素进行了实证检验。城市资源与环境效率系数的计算显示:就单个城市而言,资源与环境效率最高的城市是合肥,其次是沈阳、长春、长沙、济南,最低的是贵阳、兰州、西宁、银川、乌鲁木齐;分区域来看,资源与环境效率最高的是位于东北的城市,其次是位于东部和中部的城市,最低的是位于西部的城市。资源与环境效率影响因素的实证检验显示:产业结构对资源与环境效率有显著影响;政府财力对资源与环境效率的影响并不显著;经济外向度、人口质量对资源与环境效率有显著的正向影响。