全氟辛烷磺酸盐(PFOS)对半滑舌鳎(Cynoglossus semilaevis)免疫相关基因表达的影响

为了解全氟辛烷磺酸盐(perfluorooctane sulfonate, PFOS)暴露对半滑舌鳎(Cynoglossus semilaevis)免疫功能的影响,在实验室条件下,运用RT-PCR方法分析了PFOS暴露对半滑舌鳎热休克蛋白hsp70、hsp90、C型凝集素(c-type lectin)和细胞色素c氧化酶(cytochrome c oxidase, cox)等4种免疫相关基因表达水平的影响。实验测定了上述4种基因在半滑舌鳎肝、鳃、肠及肌肉4种不同组织中随时间(0、24 h、48 h、96 h和7 d)的表达变化情况。结果表明,在4种组织中,hsp70基因的表达与对照相比为上调,其中,肝组织hsp70基因的表达量显著高于其他各组织,且表达高峰值的出现也早于其他各组织;hsp90基因在肝和鳃组织中表达量随时间不同而波动,在肠组织中表达上调,在肌肉中表达显著下调;c-type lectin基因表达量与对照组相比表达显著下调或无明显差异;cox基因在肝组织和肠组织中表达下调,在鳃和肌肉中表达上调。上述研究结果表明,PFOS能引起免疫相关基因的表达变化,对半滑舌鳎具有潜在的免疫毒性。肝组织中各免疫基因对PFOS胁迫的响应高于其他组织。本研究可为阐明全氟辛烷磺酸盐对半滑舌鳎的免疫毒性提供基础数据。     

Ammonium nitrate thermal decomposition with additives

Runaway reactions present a potentially serious threat to the chemical process industry and the community; such reactions occur time and time again often with devastating consequences. The main objective of this research is to study the root causes associated with ammonium nitrate (AN) explosions during storage. The research focuses on AN fertilizers and studies the effects of different types of fertilizer compatible additives on AN thermal decomposition. Reactive Systems Screening Tool (RSST) has been used for reactivity evaluation and to better understand the mechanisms that result in explosion hazards. The results obtained from this tool have been reported in terms of parameters such as “onset” temperature, rate of temperature and pressure rise and maximum temperature. The runaway behavior of AN has been studied as a solid and solution in water. The effect of additives such as sodium sulfate (Na₂SO₄) and potassium chloride (KCl) has also been studied. Multiple tests have been conducted to determine the characteristics of AN decomposition accurately. The results show that the presence of sodium sulfate can increase the “onset” temperature of AN decomposition thus acting as AN thermal decomposition inhibitor, while potassium chloride tends to decrease the “onset” temperature thus acting as AN thermal decomposition promoter.     

温州近海海域海水及滩涂沉积物中PFOS和PFOA污染特征分析

为了解温州近海海域全氟辛烷磺酸(PFOS)和全氟辛酸(PFOA)的污染状况和特征,采用固相萃取/高效液相串联质谱检测法分析了采自乐清湾、瓯江口、西湾、飞云江口及洞头半屏岛的近海海水和滩涂沉积物中PFOS和PFOA污染水平。结果显示,温州近海海水普遍存在PFOS和PFOA污染,其中,PFOS的浓度范围为<1.0～31.36 ng/L,中位浓度为2.29 ng/L;PFOA的浓度范围为<1.0～23.66 ng/L,中位浓度为5.29 ng/L。滩涂沉积物样品中PFOS和PFOA的浓度范围(干重)分别为(<1.0～11.91)×10-9(中位浓度为3.60×10-9)和(1.84～34.01)×10-9(中位浓度为6.83×10-9)。温州近海海水中PFOS和PFOA的污染水平明显高于香港沿岸、中国南海海水、韩国沿岸海水和近海珠江三角洲,与大连湾的海水相当,海岸滩涂沉积物中的PFOS和PFOA浓度远高于珠江和黄浦江沉积物中的浓度。     

电石渣-石膏湿法烟气脱硫废水处理工艺研究

电石渣-石膏湿法脱硫废水与石灰石-石膏湿法脱硫废水存在差异,主要体现在悬浮物与COD较难去除,采用在中和池添加助凝剂与曝气池添加氧化剂的方法,可在沿用石灰石法脱硫废水处理工艺设计的前提下达到对电石渣法脱硫废水的良好处理效果。     

空塔钠碱法烟气脱硫实验研究

在内径200mm,高度1100mm的喷淋塔内,采用Na2CO3作为吸收剂进行SO2吸收实验,重点研究了液气比(L/G)、空塔气速、进口SO2质量浓度、吸收液pH及初始浓度对脱硫效率的影响。通过实验得到该系统适宜操作条件:吸收液pH值在6.5～7.5之间,液气比在1～1.5之间,吸收液初始浓度5%,空塔气速1.6m/s,在此条件下,进口SO2质量浓度在3000mg/m3以内,脱硫效率可以达到80%以上。     

全氟辛烷磺酸(PFOS)对斑马鱼卵黄蛋白原mRNA水平的影响

为了研究环境低剂量全氟辛烷磺酸（perfluorooctane sulfonate,PFOS）对水生生物的内分泌干扰效应和可能的作用机制,测定了PFOS对斑马鱼（Brachydanio rerio）肝脏中卵黄蛋白原（vitellogenin,VTG）mRNA水平的影响.将斑马鱼暴露于4个PFOS的环境低剂量浓度组（0.1、1、10、100μg.L-1）中进行21d毒性试验,收集肝脏样品,提取RNA,采用荧光定量PCR（qRT-PCR）分别检测VTG1和VTG3的mRNA水平.结果表明：①PFOS暴露引起雄性斑马鱼肝脏VTG1和VTG3 mRNA水平升高,VTG1 mRNA水平升高与剂量呈正相关,在100μg.L-1暴露浓度处与对照组呈现显著性差异;VTG3的mRNA水平变化与剂量呈倒U型曲线,呈现典型的毒物刺激荷尔蒙效应,在10和100μg.L-1暴露浓度处与对照组呈现显著性差异;②PFOS暴露引起雌性斑马鱼肝脏中VTG1 mRNA水平升高,在10μg.L-1暴露浓度处与对照组呈现显著性差异,但在高浓度（10和100μg.L-1）处试验结果误差较大;VTG3 mRNA水平只在10μg.L-1暴露浓度处升高,但相比于对照组均没有显著性差异.试验结果表明PFOS暴露对斑马鱼的内分泌干扰作用明显,其毒性作用机制可能是类雌激素效应,而肝脏中VTG1和VTG3mRNA水平可能作为PFOS内分泌干扰效应评价的敏感生物标志物,但VTG1和VTG3 mRNA水平的响应曲线呈现基因亚型和性别差异.     

海藻酸钠包埋活性炭与细菌的条件优化及其对Pb~(2+)的吸附特征研究

利用海藻酸钠固定化包埋活性炭与多黏类芽孢杆菌GA1,通过正交试验研究海藻酸钠溶液浓度、包炭量及包菌量吸附Pb2+的最佳配比,并研究了这种新型的固定化小球对Pb2+的吸附特征.结果表明,固定化活性炭与多黏类芽孢杆菌GA1小球最佳制备条件为海藻酸钠质量分数2.5%、包炭量1:20和包菌量1:2,在该制备条件下吸附率达到93.74%.固定化小球的最佳吸附条件为pH5、温度30℃和Pb2+初始浓度300mg·L-1,活性炭与GA1经固定后对pH、温度和Pb2+初始浓度适应范围扩大.吸附平衡曲线表明,对Pb2+的吸附在30min内是一个快速的过程,在2h时基本趋于平衡,且平衡曲线能较好地用Langmuir模型和Freundlich模型来描述,其吸附过程主要为单分子层吸附,最大单分子层吸附量为370.37mg·g-1.解吸结果表明固定化小球能有效地循环利用.     

改性粉煤灰在处理锑矿选矿废水中的应用

针对锑矿选矿废水中锑和丁基黄原酸钠严重超标的问题,用酸改性粉煤灰对其进行吸附处理.试验结果表明,当改性粉煤灰处理选矿废水的最佳质量体积比(g.mL-1)为1:100,pH值为3,静置时间为4h时,可以将选矿废水中的锑浓度从28.611mg.L-1降到0.05mg.L-1以下,去除率达99.8%以上;废水中的丁基黄原酸钠浓度可从0.373mg.L-1降到0.02mg.L-1以下,去除率达95.0%以上.处理废水后的改性粉煤灰用硫酸-硝酸浸提,浸出液中重金属离子浓度均低于国家浸出毒性标准,表明改性粉煤灰是一种很好的锑矿选矿废水处理剂.     

纳米铁系材料与反硝化细菌复合去除地下水硝酸盐氮研究

采用不同液相还原法制备了纳米Fe、纳米Fe/Ni和油酸钠包覆型纳米Fe粒子,并将其与反硝化细菌复合应用于地下水中硝酸盐氮的去除研究中.分别考察了不同纳米铁系材料与反硝化细菌复合体系去除硝酸盐氮的反应速率及对脱氮产物生成的影响.同时,从核糖核酸(RNA)水平考察了不同纳米铁系材料对反硝化细菌的影响.结果表明,纳米Fe/Ni复合体系脱氮速率最快,6d内对硝酸盐氮的去除率可达到100%,最终产物主要为氨氮,占体系总氮的69%;而纳米Fe和油酸钠包覆型纳米Fe复合体系9d可将硝酸盐氮100%去除,氨氮的转化率分别为52%和16%.另外,从反应前后反硝化细菌总RNA浓度的变化情况看,纳米Fe/Ni复合体系、纳米Fe复合体系和油酸钠包覆型纳米Fe复合体系的反硝化细菌总RNA浓度分别降低了93%、40%和34%,可见3种纳米铁系材料对反硝化细菌毒性大小顺序为:纳米Fe/Ni纳米Fe油酸钠包覆型纳米Fe.     

Effect of chemical and thermal activations on the properties of rice husk ash-based solidified wastes

Strength development,leachability and microstructure of heavy metals from the solidified waste using synthesis rice husk ash (sRHA) and lime blended at the weight ratio of 1:1 were used as binders.The heavy metal-containing sludge was used at the level of 0 wt.%,30 wt.%,and 50 wt.% dry weight,respectively.The sample specimens with and without 1.5 wt.% of sodium silicate (SiO 2 /Na 2 O=1.0) were cured under the ambient condition and elevated temperature curing at 50°C for 24 hr.Experimental results showed that the introduction of sodium silicate solution and elevated temperature curing to sRHA-based solidified waste containing 30 wt.% of heavy metal sludge gave one day strength of 20 kg/cm 2 compared to 0.9 kg/cm2 for the control sample.XRD patterns indicated that most metal-sulfides present in the sludge were appeared in the solidified waste and SEM coupled with EDX techniques reveal these metal-sulfide particles were trapped within the lime-sRHA matrices.In addition,cumulative leaching behavior by tank test (EA NEN 7375:2004) showed that solidified waste containing up to 30 wt.% of heavy metal sludge was suitable to dispose in a secured landfill.