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61.7%截至2010年12月底,这59条河流化学需氧量和氨氮平均浓度分别为23.7毫克/升和1.4毫克/升,比上年同期分别下降40.4%和61.7%。按常见鱼类能够稳定生存     

地表水中有机污染物的化学需氧量的探讨与研究

有机污染物对地表水的危害主要表现在自身氧化过程对水中溶解氧的消耗,化学需氧量（COD）是评定水中耗氧有机物含量的指标之一,本文主要研究讨论了化学需氧量指标并具体阐述了几种检测方法。     

响应面法优化厌氧上清液除磷的研究

在用铁盐对厌氧段富磷上清液进行化学磷沉淀以实现磷的回收和达标排放的SBR系统中,为了减少铁盐化学除磷残余物可能对生物处理系统的影响,采用Box-Benhnken中心组合试验原理和响应面分析法,选择Fe:P、混凝搅拌强度、絮凝搅拌强度、搅拌时间等为自变量,残余铁离子为响应值,研究自变量之间的交互作用,以期优化化学除磷条件.通过Design-Expert 8.0软件得到1个二次响应曲面模型.得出最佳除磷条件:Fe:P比为1.40:1,搅拌强度为275r/min,快速搅拌时间为30s,絮凝搅拌强度为60r/min,絮凝时间为18min,沉淀时间为20min.在此条件下,化学混凝后残余铁离子浓度为0.37mg/L,化学除磷率大于97.66%.     

Efficacy of two chemical coagulants and three different filtration media on removal of Aspergillus flavus from surface water

Aquatic fungi are common in various aqueous environments and play potentially crucial roles in nutrient and carbon cycling as well as interacting with other organisms. Species of Aspergillus are the most common fungi that occur in water. The present study was undertaken to elucidate the efficacy of two coagulants, aluminum sulfate and ferric chloride, used at different concentrations to treat drinking water, in removing Aspergillusflavus, as well as testing three different filtration media： sand, activated carbon, and ceramic granules, for their removal of fungi from water. The results revealed that both coagulants were effective in removing fungi and decreasing the turbidity of drinking water, and turbidity decreased with increasing coagulant concentration. Also, at the highest concentration of the coagulants, A. flavus was decreased by 99.6% in the treated water. Among ceramic granules, activated carbon, and sand used as media for water filtration, the sand and activated carbon filters were more effective in removing A.flavus than ceramic granules while simultaneously decreasing the turbidity levels in the test water samples. Post-treatment total organic carbon （TOC） and total nitrogen （TN） concentrations in the experimental water did not decrease; on the contrary, TN concentrations increased with the increasing dosage of coagulants. The filtration process had no effect in reducing TOC and TN in tested water.     

Antimony smelting process generating solid wastes and dust：Characterization and leaching behaviors

A large amount of solid waste has been produced by the antimony smelting process in the＂World Capital of Antimony＂, Xikuangshan area in China. This study comprehensively investigated the physical and chemical characteristics of the various solid wastes, as well as the leaching behavior of the solid wastes, which included water-quenched slag,arsenic-alkali residue, desulfurized slag and blast furnace dust. These four types of waste were enriched in a variety of heavy metals and metalloids and more specifically with As and Sb levels up to 8.6 × 104 and 3.16 × 105mg/kg, respectively, in arsenic-alkali residue. For desulfurized slag and water-quenched slag, the leaching concentration of Sb significantly exceeded the acceptable limits during the leaching tests using the toxicity characteristic leaching procedure and the synthetic precipitation leaching procedure. In addition, As leaching in arsenic-alkali residue was extraordinarily hazardous, being three orders of magnitude higher than the regulatory level of As. According to the results of the extraction tests, all the tested wastes were classified as hazardous waste.     

美国饮用水化学候选污染物的筛选过程

介绍美国国家环境保护局建立饮用水化学候选污染物清单(contaminant candidate list,CCL)的总体情况。通过第3次化学候选污染物清单的建立过程,详细介绍了CCL3的建立程序和技术内容,对化学候选污染物结合健康危害和暴露程度的筛选方法和分步实施筛选的程序进行了说明,对我国确定管制化学物质的筛选工作提供了实践参考。     

氯化铵处理含钒废水的研究

钒是一种非常重要的金属元素,被广泛用于钢铁与机械制造等行业以提高金属的抗拉强度。在钒的冶炼过程中,大量的含钒废水会排放出来,其中钒的含量也远超过《钒工业污染物排放标准》(GB 26452-2011)中规定的排放标准。如果不对含钒废水加以处理,不仅仅是钒资源的浪费,排入环境的钒会对生态系统造成巨大的危害。文章针对湿法提钒工艺排放的含钒废水,提出了用铵盐处理含钒废水的处理工艺。酸性含钒废水中,钒的主要形态为六聚钒酸盐的形态存在(V6O162-),当含废水为50 mL时(含钒207.7 mg/L),5 g/L的NH4Cl用量为25 mL,待反应60 min后,铵离子和六聚钒酸盐生成六聚钒酸铵(APV)沉淀,再通过离心除去沉淀物。该方法操作简单可行,废水中钒的去除率可达96%以上,可为含钒废水的后续达标处理奠定基础。     

地球化学定量预测法在武夷成矿带铜资源潜力评价中的应用

利用地球化学定量预测理论方法技术,建立了武夷成矿带紫金山铜金矿等7个典型矿床的地质-地球化学找矿模型,圈定了54处AB级预测区,并利用地球化学定量预测法分别估算了每类预测区的铜资源量,为科学评估武夷成矿带的铜矿资源潜力和该成矿带地质矿产勘察工作部署提供地球化学依据。     

管式法高压聚乙烯装置的道化学火灾爆炸危险指数评价

运用道化学火灾爆炸危险指数评价方法,对Quantum管式法高压聚乙烯装置中多次出现泄漏火灾的聚合单元进行评价。对照装置实际分析了防火防爆缺陷因子,提出完善聚合单元的防火防爆措施。     

基于N：P化学计量特征的高寒草甸植物养分状况研究

土壤养分条件影响不同功能群植物的养分状况与生长,这在施肥实验中已得到充分验证.然而,自然养分梯度下植物-土壤养分耦合关系的研究仍然缺乏.基于植物N∶P化学计量学特征,本研究探讨青藏高原亚高寒草甸自然养分梯度下不同功能群植物氮状况及生物量变化.2008年、2009年N∶P比值分别为9.83和11.57,其低群落N∶P比验证了该地区自然植被主要受到N素的限制.偏冗余分析(partial RDA)结果显示,随着土壤氮素可利用性的增加杂草生物量比例上升,而豆科、禾草生物量比例下降.豆科的固氮作用以及禾草的高养分利用效率分别提高其在氮限制植被中的竞争力;这些结果表明,全球氮沉降的增加将提高杂草的优势度.豆科生物量比例与群落、非豆科植物的N∶P显著正相关,表明豆科植物能够改善群落的氮状况,包括降低非豆科植物的氮限制水平.