MOVEMENT BEHAVIOUR OF MEDAKA (Oryzias latipes) IN RESPONSE TO SUBLETHAL TREATMENTS OF DIAZINON AND CHOLINESTERASE ACTIVITY IN SEMI-NATURAL CONDITIONS

Behavioural changes of medaka (Oryzias latipes) treated with an anticholinesterase insecticide, diazinon (0.1 mg L^{- 1}), were continuously observed for 4 days in semi-natural conditions. Although variations occurred in individual specimens, the movement tracks appeared differently with typical short-range movement with irregular turns and shaking after the treatments. Eight movement patterns frequently observed before and after the treatments were selected, and the variables characterising the movement patterns were compared quantitatively. The variables were clearly differentiated when the movement patterns were correspondingly matched before and after the treatments (e.g., vertical movements, horizontal movements, etc). Meander and stop duration were highly different among the selected movement patterns. Additionally, different degree of toxic response behaviours could also be detected by quantitative characterisation of the variables. Response behaviour was confirmed with toxicological experiments that show the decrease in the acetylcholine esterase activity in the head and body of specimens. Quantitative investigations on the variables of the movement tracks suggested the usefulness of response behaviour as a monitoring tool for environmental assessment.     

Water Environmental Degradation of the Heihe River Basin in Arid Northwestern China

Water environmental degradation is a major issue in the Heihe River Basin belonging to the inland river basin of temperate arid zone in northwestern China. Mankind’s activities, such as dense population and heavy dependence on irrigated agriculture, place immense pressure on available and limited water resources during the last century, especially the recent five decades. An investigation on the water environmental degradation in the Heihe River Basin and analysis of its causation were conducted. The results indicated that water environmental changes in the whole basin were tremendous mostly in the middle reaches, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Some new forms of management based on traditional and scientific knowledge must be introduced to solve problems of water environmental degradation in the Heihe River Basin.     

不同种类食细菌线虫对石油污染土壤微生物的影响

通过在石油污染土壤中接种不同种类食细菌线虫,探究土壤微生物活性和多样性的变化.本试验设置5个处理：杀灭线虫土壤（NFS）、石油污染土壤（SP）、在石油污染土壤中分别接种不同线虫,即秀丽隐杆线虫（Caenorhabditis elegans,SPN1）、头叶属线虫（Cephalobus persegnis,SPN2）和小杆属线虫（Rhabditis marina,SPN3）.结果表明,经过168d试验,和NFS相比,SP的土壤基础呼吸和脲酶活性增大,而微生物量碳含量和蔗糖酶活性减小.和SP相比,SPN1、SPN2、SPN3的基础呼吸增大,微生物量碳减少了34.59%~72.48%,蔗糖酶活性增加了15.66%~22.89%.SP、SPN1、SPN2和SPN3的微生物的丰富度（S）分别下降了5.00,7.25,2.50和9.75,Shannon-Wiener指数（H'）分别显著下降了0.18,0.15,0.15和0.23.不同种类的食细菌线虫可通过捕食作用对石油污染土壤微生物活性及多样性产生影响并有种间差异,有利于提高石油污染土壤微生物活性,促进石油降解.     

有机负荷和温度波动对厌氧菌群及酶活影响

基于太阳能辅热厌氧消化反应器进行餐厨垃圾半连续发酵试验,探究了温度波动和有机负荷调控（OLR=2.0、4.0、6.0、7.0 kg·m^-3·d^-1）对甲烷产量、酶活性变化和微生物群落结构的影响.结果表明,反应器可以在OLR为2.0 kg·m^-3·d^-1下稳定运行并在6.0 kg·m^-3·d^-1时实现最佳甲烷生产效率,虽然太阳能组比电能组减少了4倍能耗,但热辐射不稳定导致太阳能组发酵温度波动,甲烷平均产量比电能组减少21%.此外,蛋白酶在温度波动环境下表现出较高活性,但脂肪酶和淀粉酶活性却受到抑制.高通测序结果表明,低OLR阶段乙酸型产甲烷菌Methanosaeta活性较强,随着OLR递增氢营养型产甲烷菌Methanoregula和Methanospirillum相对丰度逐渐提高,而试验全过程中水解细菌Firmicutes相对丰度维持在62%~95%,占据主导地位.     

The antifungal activity of the leaf gland volatile oil of sweet gale (Myrica gale) (Myricaceae)

Summary The antifungal activity of volatile oil obtained from the leaves of sweet gale (Myrica gale) has been investigated. Fungi, isolated from the leaves ofM. gale, were grown in liquid medium containing the oil and its effect on biomass production was gauged. The oil inhibited growth of all species of fungi to greater or lesser extent. Sesquiterpenes were more active than monoterpenes, and among the sesquiterpenes germacrone was marginally more active than -elemenone. These results support the proposition that the volatile oil ofM. gale has a role in resistance to fungal pathogens.     

Antimicrobial activity of silver loaded MnO2 nanomaterials with different crystal phases against Escherichia coli

Silver-loaded MnO_2 nanomaterials(Ag/MnO_2),including Ag/α-MnO_2,Ag/β-MnO_2,Ag/γ-MnO_2and Ag/δ-MnO_2 nanorods,were prepared with hydrothermal and impregnation methods.The bactericidal activities of four types of Ag/MnO_2 nanomaterials against Escherichia coli were investigated and an inactivation mechanism involving Ag~+ and reactive oxygen species(ROS)was also proposed.The bactericidal activities of Ag/MnO_2 depended on the MnO_2 crystal phase.Among these nanomaterials,Ag/β~-MnO_2 showed the highest bactericidal activity.There was a 6-log decrease in E.coli survival number after treatment with Ag/β~-MnO_2 for120 min.The results of 5,5-dimethyl-l-pyrroline-N-oxide spin-trapping measurements by electron spin resonance indicate OH and O_2~- formation with addition of Ag/β-MnO_2,Ag/γ-MnO_2 or Ag/δ-MnO_2.The strongest peak of OH appeared for Ag/β-MnO_2,while no OH or ·O_2~-signal was found over Ag/α-MnO_2.Through analysis of electron spin resonance(ESR) and Ag+elution results,it could be deduced that the toxicity of Ag~+ eluted from Ag/MnO_2 nanomaterials and ROS played the main roles during the bactericidal process.Silver showed the highest dispersion on the surface of β-MnO_2,which promoted ROS formation and the increase of bactericidal activity.Experimental results also indicated that Ag/MnO_2 induced the production of intracellular ROS and disruption of the cell wall and cell membrane.     

太湖微囊藻光合作用活性的周年动态变化

应用Phyto-PAM浮游植物荧光仪测定了太湖微囊藻光合作用活性的周年变化,并分析了微囊藻光合作用活性参数与环境因子之间的相互关系.结果显示:冬季期间,检测不到微囊藻的光合作用活性;春季期间,微囊藻的最大光量子产量(Fv/Fm)和有效光量子产量(ΔF/Fm')呈现出快速增加趋势;夏季期间,微囊藻的光合作用活性呈现出先增加后下降趋势;秋季期间,微囊藻的光合作用活性呈现出下降趋势.梅梁湾和湖心微囊藻的最大光量子产量分别在0.34~0.55和0.28~0.50之间,平均值分别为0.42和0.39,有效光量子产量分别在0.15~0.38和0.10~0.38之间,平均值分别为0.26和0.23;非光化学荧光淬灭(NPQ)呈现出先增加后下降趋势,在8月达到最大值.光响应曲线(RLC)的3个特征参数从3月到6月呈上升趋势,之后呈现出较大波动性.相关分析结果表明,太湖微囊藻的Fv/Fm、ΔF/Fm'和NPQ之间有显著的正相关性,且均随着水温升高而增加.Fv/Fm和ΔF/Fm'与最大电子传递速率(r ETRmax)之间显著正相关,r ETRmax与TN呈显著正相关;饱和光照强度点(Ik)与TP显著正相关,与TN/TP和NO-3显著负相关.总之,太湖微囊藻的光合作用活性与水华形成及发展动态相适应,控制全球气候变暖和削减氮、磷浓度有利于抑制微囊藻光合作用活性.     

Ti-Cu-Mn复合物负载石墨烯催化剂制备及其降解二甲苯性能

采用水热法制备了4种不同摩尔比的Cu-Mn-Ti/GS复合物催化剂,利用固定式反应床评价了其对二甲苯的催化氧化性能,并对催化剂进行了BET、XRD、SEM、TEM、XPS等表征,探讨了其对二甲苯的降解动力学.结果表明,当催化剂的Cu、Mn含量增加时,其比表面积有所降低,总孔容也降低,降解活性减小.催化剂中Cu-Mn呈现Cu_(1.5)Mn_(1.5)O_4和CuMn_2O_4两种晶格,活性组分有Cu~+、CuMn O和TiO_2.石墨烯载体的稳定性较好,Ti-Cu-Mn/GS(1∶1∶1)催化剂的颗粒分布较均匀,粒径也较小,降解二甲苯的T50为97℃,表现出较好的低温催化降解性能.催化剂对二甲苯的催化氧化降解过程符合一级反应动力学方程.     

旁路水解酸化强化污泥过程减量运行性能与机理研究

旁路水解酸化技术既能实现污泥减量,又能为污水脱氮除磷补充碳源。采用水解酸化作为污泥旁路减量化技术,研究其污泥减量的运行性能和机理,同时考察了对污水处理工艺污染物去除的影响。采用污泥水解酸化旁路处理,得到污泥减量率为30%,其中水解酸化的贡献为0.7%,延长污泥龄贡献为17.1%,能量解偶联等贡献为12.2%。污泥水解酸化旁路处理对污水生物处理工艺的出水水质以及微生物活性影响不显著。水解酸化过程中会降低微生物脱氮活性,但对污水处理主反应器中微生物活性影响较小。污泥旁路水解酸化污泥减量工艺中,对污泥减量机理的解析,需要综合考虑水解酸化与污泥龄等对污泥减量效果的影响。     

SCR脱硝机组空气预热器堵塞治理建议

燃煤机组安装SCR脱硝装置后,空气预热器堵塞成为普遍现象,严重影响机组的安全性、经济性。通过对空气预热器堵塞物成分分析,提出治理空气预热器堵塞技术路线,结合实际运行中出现的问题,探寻SCR脱硝机组氨逃逸率高、SO_3浓度高、排烟温度低的原因,并且分析这些因素对空气预热器堵塞程度的影响,建议从保持催化剂活性,确保NO_x浓度,氨逃逸率均匀分布,防止氨过喷,降低入炉煤含硫量,提高锅炉排烟温度等方面,综合治理空气预热器堵塞,并提出详细的建议。