大气气溶胶酸度和酸化缓冲能力研究

为了掌握大气气溶胶与酸性降水的关系 ,分析和研究了中国北方和南方不同观测点可吸入颗粒物 (PM10 )的酸度 ,并利用微量酸碱滴定的方法测定了其酸化缓冲能力。结果表明大气气溶胶具有一定的酸度 ,同时对酸化的缓冲能力非常低 ,甚至可以促进降水的酸化 ,这种污染特征也是上述观测点发生酸性降水的重要原因之一。     

铁还原中和沉淀法处理TNT酸性废水的研究

研究了处理TNT酸性废水的铁还原中和方法。该法用铁将硝基苯类还原成苯胺类，然后通过石灰乳中和生成Fe(OH)2胶体，吸附苯胺类，达到去除硝基苯类的目的。在过量铁还原60min，中和沉淀pH8—9的最佳条件下，可将废水中的硝基苯类从82．0mg/L降到未检出程度(＜0．2mg/L)，CODcr从394．0mg/L降到94．8mg/L。处理后的废水中的苯胺类也未检出(＜0．03mg/L)。该法的物料消耗费用约为传统的活性碳吸附法的17．5％。     

Removal of Ni(II) from strongly acidic wastewater by chelating precipitation and recovery of NiO from the precipitates

Strongly acidic wastewater produced in nonferrous metal smelting industries often contains high concentrations of Ni(II), which is a valuable metal. In this study, the precipitation of Ni(II) from strongly acidic wastewater using sodium dimethyldithiocarbamate (DDTC) as the precipitant was evaluated. The effects of various factors on precipitation were investigated, and the precipitation mechanism was also identified. Finally, the nickel in the precipitates was recovered following a pyrometallurgical method. The results show that, under optimised conditions (DDTC:Ni(II) molar ratio = 4:1; temperature = 25 °C), the Ni(II) removal efficiency reached 99.3% after 10 min. In strongly acidic wastewater, the dithiocarbamate group of DDTC can react with Ni(II) to form DDTCNi precipitates. Further recovery experiments revealed that high-purity NiO can be obtained by the calcination of DDTCNi precipitates, with the nickel recovery efficiency reaching 98.2%. The gas released during the calcination process was composed of NO₂, CS₂, H₂O, CO₂, and SO₂. These results provide a basis for an effective Ni(II) recovery method from strongly acidic wastewater.     

土壤与酸性含氟溶液相互作用特征及机理研究

通过反复多次提取实验方法模拟了酸性含氟溶液与红壤和赤红壤相互作用过程。结果表明：在相互作用过程中，土壤中氟含量不同对土壤溶液pH有明显不同的影响。当氟含量较低时氟离子对土壤溶液pH的影响不明显；当浓度较高时则可大大提高土壤溶液的pH，缓冲土壤酸化。在第一次提取中因氟的大量吸附可减少溶液中铝的浓度，且氟含量越高铝浓度越少量越大。随提取次数增加土壤溶液中铝、氟浓度同时增加，且氟含量越高铝浓度越大，其中氟以AI－F络合物为主。     

Oxidation of As(Ⅲ) by potassium permanganate

The oxidation of As(Ⅲ) with potassium permanganate was studied under conditions including pH, initial As(Ⅲ) concentration and dosage of Mn(Ⅶ). The results have shown that potassium permanganate was an effective agent for oxidizing of As(Ⅲ) in a wide pH range. The pH value of tested water was not a significant factor affecting the oxidation of As(Ⅲ) by Mn(Ⅶ). Although theoretical redox analyses suggest that Mn(Ⅶ) should have better performance in oxidization of As(Ⅲ) within lower pH ranges, the experimental results show that the oxidation efficiencies of As(Ⅲ) under basic and acidic conditions were similar, which may be due to the adsorption of As(Ⅲ) on the Mn(OH)2 and MnO2 resulting from the oxidation of As(Ⅲ).     

我国东部七省生态系统对酸沉降的相对敏感性

讨论了影响亚热带生态系统对酸沉降敏感性的生态因子，提出了敏感性等级划分的指标体系，根据大量资料编制了我国东部７省１市生态系统对酸沉降相对敏感性分区图。结果表明，在研究区域内生态系统的敏感性有相当大的差别，极敏感区和敏感区面积占全区总面积的１／３以上，主要分布在福建、浙江、江西３省。     

Temporal and spatial relationships in fine particle strong acidity, sulphate, PM1O, and PM2.5 across multiple canadian locations

The Canadian Acid Aerosol Measurement Program (CAAMP) was established in 1992 to gain a better understanding of the atmospheric behaviour of fine particle strong acidity (“acid aerosols”) and to facilitate an assessment of the potential health risks associated with acid aerosols and particles in general. During 1992. 1993 and 1994, annular denuder and filter measurements were taken at four sites in Ontario, two in Quebec, three in the Atlantic Provinces and one in the greater Vancouver area. Mean fine particle sulphate concentrations (SO₄²⁻) were highest in southern Ontario (annual average ranged from 40–70 nmol m⁻³), lowest at a site in the Vancouver area (average = 16 nmol m⁻³) and second lowest in rural Nova Scotia. However, mean fine particle strong acid concentrations (H⁺) were geographically different. The highest mean concentrations were at the east coast sites (annual average of up to 30 nmol m⁻³). Acidities were lower in areas where the fine particle acidity experienced greater neutralization from reaction with ammonia. This included the major urban centres (i.e. Toronto and Montréal) and areas with greater amounts of agricultural activity, as in rural southern Ontario. On average, ambient concentrations of fine and coarse particle mass were larger in the urban areas and also in areas where SO₄²⁻ levels were higher. All the particle components were episodic. However, compared to SO₄²⁻ and fine particles (PM_2.5 or PM_2.1, depending upon inlet design), episodes of H⁺ tended to be less frequent and of shorter duration, particularly in Ontario. Saint John, New Brunswick, had the highest mean annual H⁺ concentration, which was 30 nmol m⁻³. H⁺ episodes (24 h concentration > 100 nmol m⁻³) were also the most frequent at this location. The high levels in Saint John were partially due to local sulphur dioxide sources and heterogeneous chemistry occurring in fog, which, on average, led to a 50% enhancement in sulphate, relative to upwind conditions.There was a substantial amount of intersite correlation in the day to day variations in H⁺, SO₄²⁻ , PM_2.5 and PM₁₀ (fine + coarse particles) concentrations, which is due to the influence of synoptic-scale meteorology and the relatively long atmospheric lifetime of fine particles. Sulphate was the most regionally homogenous species. Pearson correlation coefficients comparing SO₄²⁻ between sites ranged from 0.6 to 0.9, depending on site separation and lag time. In many cases, particle episodes were observed to move across the entire eastern portion of Canada with about a two-day lag between the SO₄²⁻ levels in southern Ontario and in southern Nova Scotia.     

宁南霉素诱导烟草酸性病程相关蛋白的研究

研究了宁南霉素对烟草酸性病程相关蛋白的诱导表达．结果表明，宁南霉素可系统性地诱导烟草叶片中酸性病程相关蛋白的高效表达．与水杨酸相比，宁南霉素诱导酸性病程相关蛋白的表达水平较高，持续时问较长．此外，在同一品种不同形态叶片烟草植株中，宁南霉素对植物酸性病程相关蛋白的诱导存在差异．图6表3参20     

铁矿酸性排水的人工湿地处理

在排放酸性重金属废水的铁矿排土场建设人工湿地处理系统,面积130m~2,废水流量0.5m~3/h,经过两个月的运行测试结果表明:人工湿地系统能有效地处理酸水.酸水pH值由2.6升高到6.1;铜离子由25.79×10~(-6)减少到0.099×10~(-6),去除率为99.7%;铁离子由36.50×10~(-6)降到0.031×10~(-6),去除率为99.8%;锰离子从393.6×10~(-6)降低到107.20×10~(-6),去除率为70.9%.     

增施磷肥对提高强酸性高硒茶园土壤硒有效性的效果

通过大田试验,研究了增施钙镁磷肥、过磷酸钙及与生物有机肥混施共6种调控措施对强酸性高硒茶园土壤基本化学性质、土壤有效硒和茶叶中硒质量比的调控效果.结果表明,不同磷肥及不同用量处理对土壤有效硒质量比增加均有效果,高用量的3种处理(钙镁磷肥高用量与生物有机肥混施、钙镁磷肥高用量和过磷酸钙高用量)效果好于正常用量的处理(钙镁磷肥正常用量与生物有机肥混施、钙镁磷肥正常用量、过磷酸钙正常用量),且用量相同的情况下,伴有生物有机肥的磷肥处理效果最好.增施磷肥调控均不同程度地增加了茶叶硒质量比,6种处理的增幅均达到极显著水平(p＜0.01).