动力学光度法测定环境样品中微量钒

本文研究了V(Ⅳ)对Cr_2O_7~(2-)-I~--淀粉氧化还原反应体系的诱导作用,以此为基础提出了一种测定微量钒的动力学新方法,并建立了测定最佳条件:[Cr_2O_7~(2-)]=8.4×10~(-5)mol·L~(-1),[I~-]=2.1×10~(-3)mol·L~(-1),pH=2.1,585nm。在此条件下,钒(Ⅳ)含量在0—6.6μg·ml~(-1)范围内符合比尔定律,方法检测限为0.02μgV(IV)·ml~(-1)。除Fe~(3+),Fe~(2+),Sn~(2+),Ti~(3+)外,其它共存离子不影响测定。用本方法测定了几种环境样品中的微量钒,结果满意,标准加入回收率为95.1—98.3％。     

Enhanced performance of alkali-modified Bi2WO6/Bi0.15Ti0.85O2 toward photocatalytic oxidation of HCHO under visible light

Environmental Science and Pollution Research - Photocatalytic oxidation of formaldehyde (HCHO) is considered as one of the promising ways to resolve indoor air HCHO pollution. TiO2 has been well...     

社会环境检测机构质量监管措施研讨

就目前的情况而言,我国在社会环境检测机构质量不容乐观。因此,我们应该根据实际情况,来设置相应的社会环境检测监管方案。我们可以通过严格规范社会环境检测机构市场准入门槛、创设专门的社会环境检测机构质量监管部门、创设社会环境检测机构网上投诉平台等方式,来提升监管力度,让社会环境检测机构正确发挥其应有的作用。     

蜡染废水在线处理回用及热能回收工程实例

采用絮凝沉淀-ClO2脱色-砂滤-微波无极紫外光催化氧化工艺对青岛凤凰印染有限公司蜡染印花水洗废水进行处理,详细论述了该工艺的运行特点、处理及回用效果。结果表明,在进水COD及色度波动很大的情况下,处理后废水水质长期稳定达到COD100 mg/L,色度10倍,其他各项水质指标均可满足蜡染水洗工序的生产回用要求,并回收了水中的热能。废水回用率达80%,日节水200 t,节约热能折合成标准煤约为1 t,为印染行业完成节能20%,减排20%的总体目标提供了新的思路。     

微生物降解前后COD差值法快速测定BOD

采用活性污泥曝气法降解前后COD差值的方法,进行了BOD快速检测的研究。条件实验结果表明,其适宜检测条件为:降解时间180 min;污泥量5 mL/100 mL;pH值7.0;温度25℃。模拟废水检测结果表明,该测定方法具有较高的重复性,5次测定的相对偏差小于6.5%,在BOD浓度为0~500 mg/L范围内,微生物降解前后COD差值与BOD5有良好的相关性,其相关系数达到0.98。因此,可以通过测定微生物降解前后COD值,实现快速BOD检测的目的,同时,也可实现COD和BOD一体化检测,这将是今后COD和BOD检测研究的发展方向之一。     

均衡的植物养分有助于增强茶树抵御真菌的能力从而减少杀虫剂的使用

人们正加大努力以求最大限度地降低杀虫剂的使用,这些杀虫剂是控制茶树和其它作物的病虫害的基本手段 .在中国,由于土壤常常缺少碳酸钾,所以适量使用这种养料有助于减少对杀虫剂的需要 .已经证实,在土壤中加入钾后,茶树感染真菌病的比率下降 .     

Odour emission characteristics of 22 recreational rivers in Nanjing

The odour emission characteristics of 22 recreational rivers in Nanjing were investigated and analysed. Eight odorous compounds (ammonia (NH₃), hydrogen sulphide (H₂S), sulphur dioxide (SO₂), carbon disulphide (CS₂), nitrobenzene (C₆H₅NO₂), aniline (C₆H₅NH₂), dimethylamine (C₂H₇N), and formaldehyde (HCHO)) were measured in odour emission samples collected using a custom-made emission flux hood chamber. The results showed that all odorants were detected in all monitoring rivers. NH₃ was the main odorant, with emission rates ranging from 4.86 to 15.13 μg/min m². The total odour emission rate of the Nan River, at 1 427.07 OU/s, was the highest of the all investigated rivers. H₂S, NH₃ and nitrobenzene were three key odour emission contributors according to their contributions to the total odour emission. A correlation analysis of the pollutants showed there was a significant positive correlation between the emission rate of NH₃ and the concentration of ammonia nitrogen (NH₄ ⁺-N) and total nitrogen (TN). The H₂S and SO₂ emission rates had a significant positive correlation with sulphides (S^2?) and available sulphur (AS) in the water and sediment. The content of TN, NH₄ ⁺-N, S^2? and AS in the water and sediment affected the concentration of H₂S, SO₂ and NH₃ in the emission gases. NH₄ ⁺-N, S^2? and AS are suggested as the key odour control indexes for reducing odours emitted from these recreational rivers. The study provides useful information for effective pollution control, especially for odour emission control for the recreational rivers of the city. It also provides a demonstrate example to show how to monitor and assess a contaminated river when odour emission and its control need to be focused on.     

影响钝顶螺旋藻固碳的环境因子优化

为了提高钝顶螺旋藻生长过程中的固碳速率,从CO2浓度、温度和光周期3个主要环境因子进行优化。实验结果表明,钝顶螺旋藻在2 L三角瓶中培养时,最佳培养条件为10%CO2,温度30℃,光周期16/8。最佳培养条件下,钝顶螺旋藻对数生长期内比生长速率与固碳速率均达到峰值0.512 d-1和42.506 mg/(L.h)。此外,钝顶螺旋藻的底物消耗表明培养液中的N、P足量,其初始添加量可以满足藻体的生长需要;生长过程中补加10%CO2一方面补充钝顶螺旋藻可吸收碳源,另一方面有利于缓解培养液pH升高对藻生长的影响。     

用于地表水反硝化的纤维素碳源选择研究

为了选取合适的天然有机物作为反硝化细菌碳源用于解决地表水中NO3--N污染问题,以江南大学校内湖水为接种物,选取8种天然纤维素碳源在缺氧状态不同的处理方式下对60 mg/L NO3--N的降解特性进行研究。结果表明,以碱处理作为预处理可明显提高反硝化速率,碳源脱氮率均在96%以上（树皮除外）。2种处理方式中均有NO2--N累积,部分碳源释放NH4＋-N并发生DNRA反应,树叶在2种处理中脱氮效果均较好。结合各碳源脱氮率、耗碳源量以及处理成本,选取基本处理的香樟叶作为最佳纤维素碳源。