Effects of different Ca2+ behavior patterns in the electric field on membrane fouling formation and removal of trace organic compounds

The effects of Ca²⁺on membrane fouling and trace organic compounds(TrOCs) removal in an electric field-assisted microfiltration system were investigated in the presence of Na+alone for comparison. In the electric field, negatively charged bovine serum albumin(BSA)migrated towards the anode far away from the membrane surface, resulting in a 42.9% transmembrane pressure(TMP) reduction in the presence of Na+at 1.5 V. In contrast, because of the stronger charge shielding of Ca²⁺     

燃煤流化床锅炉PAHs排放的试验研究

针对大型燃煤循环流化床锅炉，研究锅炉负荷和钙硫比对烟气中及电除器飞灰中多环芳烃含量和种类的影响，试验结果表明：随着锅炉负荷和钙硫比升高，烟气中和飞灰中多环芳烃的种类和含量减少，但负荷和钙硫比对烟气中和飞灰中多环芳烃的影响效果是不同的。     

钙硫比对烧结烟气循环流化床脱硫效率的影响

对不同钙硫比条件下烧结烟气循环流化床脱硫效率进行了研究,研究结果表明:在循环流化床脱硫系统中,保持烟气流量、循环物料量、喷水量、进出口烟气温度、入口SO2浓度等参数不变的条件下,提高钙硫比在短时间内并不能明显提高脱硫效率,其影响脱硫效率是通过钙硫比的改变实现循环物料量成分的变化,使循环物料量中有效吸收剂的比例增加,从而实现脱硫效率的提高。     

生物壳体Sr/Ca、Mg/Ca、~(87)Sr/~(86)Sr比值在恢复古气候、古环境中的应用——以小渡口剖面为例

生物壳体的Sr/Ca、Mg/Ca比值能反映其沉积水体的Sr/Ca、Mg/Ca比值 ,在一定条件下反映水体的盐度、温度 ,并分别与宿生水体的盐度、温度呈正比关系。生物壳体的87Sr/ 86Sr比值是恢复盆地古水文条件的一种重要手段。本文以著名的泥河湾盆地小渡口剖面的第 2 8层为实例 ,力图通过对有孔虫、介形虫、腹足类生物壳体Sr/Ca、Mg/Ca比值与87Sr/ 86Sr比值的对比研究 ,并结合前人所作的中更新世古地理特征研究 ,来恢复生物壳体沉积时泥河湾古湖水的温度、盐度 ,进而进行古气候、古环境的恢复。研究结果表明 :在 0 .97～ 0 .94Ma间 ,古泥河湾湖为一陆相湖泊 ,湖水的温度、盐度变化趋势相吻合 ,均呈低—高—低的演化特征 ,可能对应着盆地水体的扩展—退缩—扩展变化。其中 ,在 0 .96～ 0 .95Ma间 ,古泥河湾湖具有较高的温度、盐度特征。     

粉煤灰处理活性艳红K-2BP染料模拟废水试验

研究了粉煤灰及其与混凝剂、Ca(OH)2共同处理活性艳红K-2BP染料模拟废水的处理效果。结果表明,pH值对粉煤灰去除废水色度有较大影响,最佳pH值为12.3;随着染料废水起始浓度的增加,粉煤灰投加量相同,其对色度的去除率减小,但粉煤灰对染料的吸附容量增加;粉煤灰与混凝剂共同处理时,粉煤灰吸附对去除色度的作用更大;粉煤灰与Ca(OH)2共同处理时,可以使废水的色度去除效果提高12%左右;在粉煤灰-Ca(OH)2中再加入PAC,可以使去除率达89%以上,但PAC对色度去除率提升不明显。     

一种新型消毒剂的杀藻研究

由藻类过量繁殖引发的富营养化所造成的危害越来越严重并日益受到关注，采用钠法工艺生产的次氯酸钙是一种无残毒，不产生二次污染的高效广谱灭菌药物，对该药物的杀灌效率进行了生物测试的结果表明，它能有效地杀灭引发水华的绿藻，蓝藻和硅藻，≥62.5ppm（有效氯含量，下同）曝露96h，4种被试藻类的死亡率可达92％－100％，高浓度（500ppm)条件下，绿藻，蓝藻和藻分别在几分钟和1h内全部死亡，≤1p pm的浓度对4种被试藻类基本上不造成严重伤害。     

离子色谱法测定矿泉水中K+、Ca2+、Na+、Mg2+、Cl-、SO2-4

采用离子色谱法同时测定矿泉水中的K+、Ca2+、Na+、Mg2+、Cl-、SO2-4,方法线性良好,检出限为0.01 mg/L～0.09 mg/L,实际水样平行测定的RSD≤0.8%,加标回收率为91.7%～105%,标准样品的测定结果符合要求.     

Impact of Coal Power Plant Emission on the Foliar Elemental Concentrations in Plants in a Low Rainfall Tropical Region

A field study was conducted around two thermal power plants of India to quantify the changes in foliar elemental concentrations due to emission in a low rainfall tropical area. Sulphur dioxide and particulates were at high levels which may cause serious ecological effects. Emission from the power plants has altered the elemental concentrations in the leaves of evergreen and deciduous plants. The foliar total-S and SO₄ ^2–-S levels were significantly higher in all the plants growing at polluted sites. However, the organic-S content was more or less unaltered. In evergreen plants, the SO₄ ^2–-S content increased gradually from summer through winter, whereas in the deciduous plants there was a higher magnitude of increase after onset of new leaves during summer. With the increasing pollution load, foliar Ca²⁺ and K⁺ contents increased, whereas N content decreased. The reduction in N content was greater during summer in evergreen plants and during winter in deciduous plants. The plants growing closer to the power plants accumulated more trace elements (Mn, Fe, Cd, Pb and Ni) as compared to those growing at distant sites. In deciduous plants the leaf fall during winter lowered down the trace element     

Molecular genetic differentiation in earthworms inhabiting a heterogeneous Pb-polluted landscape

A Pb-mine site situated on acidic soil, but comprising of Ca-enriched islands around derelict buildings was used to study the spatial pattern of genetic diversity in Lumbricus rubellus. Two distinct genetic lineages (‘A’ and ‘B’), differentiated at both the mitochondrial (mtDNA COII) and nuclear level (AFLPs) were revealed with a mean inter-lineage mtDNA sequence divergence of approximately 13%, indicative of a cryptic species complex. AFLP analysis indicates that lineage A individuals within one central ‘ecological island’ site are uniquely clustered, with little genetic overlap with lineage A individuals at the two peripheral sites. FTIR microspectroscopy of Pb-sequestering chloragocytes revealed different phosphate profiles in residents of adjacent acidic and calcareous islands. Bioinformatics found over-representation of Ca pathway genes in EST_Pb libraries. Subsequent sequencing of a Ca-transport gene, SERCA, revealed mutations in the protein's cytosolic domain. We recommend the mandatory genotyping of all individuals prior to field-based ecotoxicological assays, particularly those using discriminating genomic technologies.     

上海某水厂的污泥调质研究

本文针对上海某水厂污泥调质后脱水性能不好、泥饼的含固率不高等问题,开展了污泥调质的优化实验。研究表明,4种调质方式中采用"PAM+Ca(OH)2"联合调质的污泥脱水性能最好,药剂费用适中,滤液pH从7上升至10左右;PAM单独调质在经济上最优,干污泥产生量最少,但污泥比阻值最高,且脱水污泥的资源化难度大。结合水厂已有设施,建议采用PAM与石灰联合调质方式,投加剂量分别为PAM投加2.0‰、Ca(OH)2加入5.0%。