典型铬渣简易掩埋场铬渣及土壤铬污染特征和处置分析

通过钻孔采样分析,研究了典型铬渣简易掩埋场地下铬渣及土壤铬中Cr6 、总Cr的分布特征和污染状况,结果表明,铬渣简易掩埋场铬污染程度严重,引起了周边和地下深部较大面积的土壤污染,深度达到了地下的基岩.铬含量在土壤层剖面中分布呈现规律性变化,即随土壤深度增加,Cr6 、总Cr含量逐渐下降,但绝大多数超过了危险废物毒性鉴别标准.从铬污染程度上看,总体上存在铬渣>土壤>人工填土.在此基础上,提出了铬渣及污染土壤的处置方式,为铬渣污染治理和资源化利用提供科学依据.     

聚二甲基二烯丙基氯化铵与聚合硫酸铁复合絮凝剂的制备及应用研究

在一定温度下 ,将聚二甲基二烯丙基氯化铵 (PDMDAAC)溶解在聚合硫酸铁 (PFS)中 ,制成稳定的均相复合溶液。采用FT IR和X 射线衍射对其固体结构进行了分析。考察了液体复合絮凝剂的稳定性和固体复合絮凝剂的吸湿溶解性能 ,及其对生活污水的处理效果。结果表明 :在 6 0℃以下制备的液体复合絮凝剂具有良好的稳定性 ,固体复合絮凝剂具有良好的溶解性和比PFS更强的吸湿性 ;复合絮凝剂不是由PDMDAAC与PFS简单的机械混和 ,而是互相融合的复合体系 ;具有比PFS更优的去污性能和与PFS类似的较宽的最佳投药范围和 pH适用范围。对浊度和COD分别为 10 5 2和 187 5mg/L ,pH值为 7 5 9的生活污水 ,复合絮凝剂中Fe3 + 和PDMDAAC最佳用量分别为 5 4 .15和 4 2 7mg/L ,对COD的去除率为 77 14 % ,比PFS在用量为 81 2 2mg/L时的最佳效果高 12 %。     

Cobalt exposure in relation to cardiovascular disease in the United States general population

Environmental Science and Pollution Research - Cobalt exposure has adverse health effects on the cardiovascular system in occupational and laboratory studies, but these effects have not been...     

Enrichment and characterization of an effective hexavalent chromium-reducing microbial community YEM001

Environmental Science and Pollution Research - Chromium (Cr) is one of the most widely used heavy metals in industrial processes, resulting in water and soil pollution that seriously threaten...     

长江三角洲的的生产力布局、基础设施与城市发展

随着社会经济的发展，长江三角洲的生产力布局也发生相应的变化，针对其现状特征和发展动向，论述了生产力布局的基本框架以及相关的基础设施、城市发展等问题。     

充分利用农业资源,发展我国粮食生产

我国粮食生产的制约因素较多。为了达到我国粮食产量稳定增长的目的,我们必须针对我国农业资源的特点,趋利避害,充分发挥其优势,挖掘生产潜力;搞好宏观调控,调动各方面的积极性,发展粮食生产。这样,2000年实观我国粮食总产量达到 5亿t,人均占有粮食400kg 的目的是可能的。     

气相色谱——火焰光度法测定废水中黄磷的方法研究

研究了以苯为萃取剂，用气相色谱－－火焰光度法测定废水中的微量黄磷。结果色谱分离良好，萃取率大于９４％，水样易于保存，溶剂和杂质不干扰测定，水样加标回收率大于８８．４８％，精密度重复测定的变异系数不大于３．２％，定性检出限为２μｇ／Ｌ，定性检出限为６μｇ／Ｌ。     

硫铁矿烧渣制备硫酸亚铁及效益估算

本文将硫铁矿烧渣熟化处理后得到酸性硫铁铁溶液。正交实验说明影响铁回收率的熟化因素强弱依次为硫酸浓度〉熟化时间〉熟化温度〉硫酸用量，最佳条件下，铁回收率可达９０％，利用废铁还原上述有够制备得到含ＦｅＳＯ４．７Ｈ２Ｏ９８％以上的产品，用这种方法充酸亚铁具产品质量好、环境效益和经济效益佳。     

Effects of temperature on population growth and intake of food by the army worm, Mythimna separata (Walker)

Population life tables of the army worm, Mythimna separata, were constructed and nutritional parameters of food for the larvae were examined at 5 temperatures from 16℃ to 32℃. The temperature suitable for growth and reproduction of the insect ranged from 20℃ to 28℃ with the optimum of 24℃. Their survivalship and fecundity were much poorer at 32℃ than at 16℃. Indices of population trend of the insect at these temperatures could well fitted with the parabolic curve which theoretically indicated that the population density would multiply by some 660 after one generation circle at the optimal temperature, 22.6℃, and it would decline at temperatures higher than 32.9℃ or lower than 12.3℃. Larval food intake and their AD tended to go up while their ECI and ECD to go down with a rise in temperature. These alterations in population size and feeding behavior caused by temperature would exert an important effect on their damage to crops.     

海岛土地与土地系统生态设计刍议

本文依据生态学理论对海岛土地及土地系统生态功能进行了重新的认识,并探讨了海岛土地系统生态设计的依据、原则和模式.设计中强调以土地系统生态保护性功能为主体,以海岛土地系统高层次调合发展作为海岛建设的最终目标.