非活体生物质对水中活性艳红X-3B的吸附研究

研究了4种非活体生物质(米酒糟、花生壳、柚子皮、稻草秸秆)对模拟废水中活性艳红X-3B的吸附条件及吸附机理。结果表明,活性艳红X-3B初始浓度为100 mg/L、pH为1.0~2.0、吸附剂浓度为10 mg/L时,4种吸附剂对活性艳红X-3B的吸附率可达到80%。吸附在60 min左右达平衡后最大吸附量的顺序为:米酒糟(58.8 mg/g)花生壳(28.0mg/g)柚子皮(23.6 mg/g)稻草秸秆(19.5 mg/g)。在达最大吸附率时,米酒糟的用量可减少一半、pH范围可宽为1.0~6.0,且吸附量是另三者的2倍以上。综合比较,米酒糟具有较强的吸附废水中活性艳红X-3B的能力,可作为废水中活性染料的吸附剂使用。而花生壳、柚子皮和稻草秸秆的吸附能力相对较弱,不是理想的吸附材料。数学模型模拟表明,米酒糟和柚子皮的吸附过程更符合Freundlich方程,而花生壳和稻草秸秆更符合Langmuir方程;动力学研究表明4种吸附剂的吸附拟合更符合拟二级动力学方程。     

铁炭复配修复地下水中NO_3~--N的条件研究

采用了铁炭复配修复地下水中NO3--N,探讨了实验条件对修复效果的影响。结果表明,在pH值近中性条件(初始pH 6.42)下,反应时间为1 h时NO3--N修复率达到60.85%;Fe/C=1∶1时介质最佳用量分别为4~5 g;Fe/C=1/1.5时修复率为72.80%;反应速率在高振荡强度下大于低振荡强度;氧化铜的催化效果最好,可使修复率提高7.5个百分点。铁炭复配介质修复地下水中NO3--N是有效可行的,修复率随反应时间的增加而提高,在Fe/C=1∶1时修复率与介质用量呈正相关,无限减小Fe/C比并不能无限提高修复率,振荡强度对修复具有显著影响,低振荡强度下的修复过程较高强度存在滞后现象,并非所有金属氧化物催化剂对铁炭修复NO3--N均有促进作用。     

Impact of nano-CuO stress on rice (Oryza sativa L.) seedlings

Indiscriminate release of metal oxide nanoparticles (NPs) into the environment due to anthropogenic activities has become a serious threat to the ecological system including plants. The present study assesses the toxicity of nano-CuO on rice (Oryza sativa cv. Swarna) seedlings. Three different levels of stress (0.5 mM, 1.0 mM and 1.5 mM suspensions of copper II oxide, <50 nm particle size) were imposed and seedling growth performance was studied along control at 7 and 14 d of experiment. Modulation of ascorbate–glutathione cycle, membrane damage, in vivo ROS detection, foliar H₂O₂ and proline accumulation under nano-CuO stress were investigated in detail to get an overview of nano-stress response of rice. Seed germination percentage was significantly reduced under stress. Higher uptake of Evans blue by nano-CuO stressed roots over control indicates loss of root cells viability. Presence of dark blue and deep brown spots on leaves evident after histochemical staining with NBT and DAB respectively indicate severe oxidative burst under nano-copper stress. APX activity was found to be significantly increased in 1.0 and 1.5 mM CuO treatments. Nevertheless, elevated APX activity might be insufficient to scavenge all H₂O₂ produced in excess under nano-CuO stress. That may be the reason why stressed leaves accumulated significantly higher H₂O₂ instead of having enhanced APX activity. In addition, increased GR activity coupled with isolated increase in GSH/GSSG ratio does not seem to prevent cells from oxidative damages, as evident from higher MDA level in leaves of nano-CuO stressed seedlings over control. Enhanced proline accumulation also does not give much protection against nano-CuO stress. Decline in carotenoids level might be another determining factor of meager performance of rice seedlings in combating nano-CuO stress induced oxidative damages.     

钛基IrO2-SnO2电极在烟气海水脱硫恢复系统中的应用

采用浸渍-热分解法制备了含IrOx-TiO2中间层的IrO2-SnO2电极,得到的电极具有较高的析氯电催化活性和较强的稳定性,并通过电化学氧化法对Na2SO3海水脱硫模拟液进行处理,考察了电流密度、温度、pH值和电解时间等电解工艺参数对Na2SO3去除率和化学需氧量COD的影响。结果表明,在电流密度为200 mA/cm^2,pH值为3.5,电解440 mg/L的Na2SO3海水脱硫模拟液,15 min时Na2SO3去除率可达96.5%,COD去除率可达82.6%。     

三维有机LDH的制备及其对有机物的普适性吸附

以表面活性剂十二烷基硫酸钠(SDS)为软模板剂,制得有机三维花状层状双金属氢氧化物(3D-SLDH).采用X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线能谱仪(EDS)和N2吸附-脱附等表征手段对3D-SLDH的结构进行表征,确定最佳合成尿素浓度,并通过静态吸附实验考察了3D-SLDH对金橙Ⅱ(AO7)、罗丹明...     

Decreased blood level of β2-microglobulin in the employees of a factory which produced polychlorinated biphenyls

Under the project of evaluating the health status of the employees of CHEMKO factory (East Slovakia) which produced PCBs between 1955 and 1985, the level of β₂-microglobulin (β₂-m) was measured in the serum of 242 subjects from CHEMKO (Group A) and two control groups from much less polluted areas: 1. 277 females from a small mountainous village (Group B), 2. 179 adults from the area of a large city of Ko ice (Group C). The level of thymidine kinase (TK) was measured in the groups A and B only. In addition, age-matched groups of 155 women each from all areas were evaluated. In both the whole group and the age-matched group from CHEMKO the level of β₂-m was significantly lower (P<0.001) than that in the respective control groups, while no difference was found in the level of TK. In conclusion, it is suggested that the decrease of β₂-m in CHEMKO employees might be related to the immunotoxic effects of organochlorines.     

一种新型复合球填料在低浓度污水再生回用中的应用研究

新型复合球填料为沸石与悬浮球填料的有机组合体,密度约为0.92～0.97g/cm3,比表面积为711～1185m2/m3,表面粗糙,物化性能稳定.在曝气量为20∶1,停留时间为6 h时,装有新型复合球填料的反应柱挂膜容易,成膜时间短,膜不易脱落,且生物相丰富.膜成熟时对生活污水中的氨氮和COD都有很好的去除效果,出水氨氮浓度≤2 mg/L,去除率≥93%;出水COD浓度≤22 mg/L,去除率≥80%.新型复合球反应柱在稳定状态处理低浓度的二级出水时,出水氨氮浓度≤2 mg/L,去除率≥89%,出水COD浓度为10～36 mg/L,去除率为48%～81%.出水水质符合GB50335-2002标准.     

H2S、NH3混合臭气在生物滴滤池中的净化研究

研究了生物滴滤塔净化含H2S与NH3臭气最佳的生态条件为:在温度为25 ℃、气体通气量为0.4 m3/h、营养盐喷淋量为8.0 L/h、入口H2S质量浓度712.80-948.80 mg/m3、入口NH3质量浓度422.20-795.40 mg/m3、pH值7.0-8.0之间的情况下,去除效率可达90%以上.生物滴滤塔在处理H2S和NH3混合气时,塔内pH值保持在6.5-8.5之间,此pH值对反应器中优势菌的生长繁殖不会造成太大影响,对处理效果影响不大,因此反应过程可不用对pH值进行调节,节约运行成本.     

光助Ce-Fe/Al2O3催化H2O2降解阳离子红GTL模拟废水

利用Ce-Fe/Al₂O₃为催化剂的非均相光Fenton体系降解阳离子红GTL模拟废水，考察了H₂O₂浓度、催化剂用量、初始pH值及不同工艺过程对降解效果的影响，通过紫外-可见漫反射光谱、红外光谱、XPS手段研究铁在反应中的价态变化。结果表明，在11 W低压汞灯照射下，非均相光Fenton体系能够有效地降解结构稳定的阳离子红GTL，在pH 6，反应温度20℃，时间90 min，Ce-Fe/Al₂O₃ 2 g/L，H₂O₂浓度340 mg/L，含50 mg/L阳离子红GTL模拟废水TOC去除率为92.40%；光Fenton反应中Fe(Ⅲ)转化为Fe(Ⅱ)。