共查询到20条相似文献,搜索用时 171 毫秒
1.
邻苯酸二甲酯(PAEs)是环境中常见的环境激素类污染物,其水解与光解速率异常缓慢,微生物降解是PAEs消减的重要途径。文章以邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)为目标污染物,研究了蛋白核小球藻和斜生栅藻分别降解DEP和DBP的性能及机理。结果表明:斜生栅藻-菌复合体系和小球藻-菌复合体系能快速降解DEP和DBP,且降解过程符合一级动力学方程。暗培养斜生栅藻对DBP的生物降解率低于藻-菌复合体系,而光照条件的改变对于小球藻降解DEP并未造成明显影响;无菌微藻对DEP和DBP的降解率均显著低于所对应的藻-菌复合体系。16S r RNA分析结果表明蛋白核小球藻和斜生栅藻际附生菌主要包括5种菌属,分别为噬氢菌属、劳尔氏菌属、根瘤菌属、norank_f__norank_o__Chloroplast、norank_f__Mitochondria。研究表明,微藻与藻际附生菌在PAEs的降解过程中具有良好的协同作用。 相似文献
2.
斜生栅藻降解苯酚的动力学研究 总被引:10,自引:0,他引:10
研究结果表明,斜生栅藻在驯生化10d后具备降解苯酚的能力,在200mg/L初始浓度下5d时间内苯酚被全部降解,日平均降解速率达40mg/L。在400mg/L初始浓度下,6display status时间内日平均降解速率为7.5mg/L。在高初始浓度的苯酚不仅明显抑制了斜生栅藻 生长,而且抑制了斜生栅藻的降解活性,导致降解速率下降解用最提出的生物降解二经反应 相似文献
3.
4.
《环境科学文摘》1997,(3)
X592 9701600斜生栅藻与单甲眯的相互作用/阎海…(中科院生态环境研究中心)//环境科学/中科院生态环境研究中心一1996,17(4)一39~40,43 环信X一5 为研究斜生栅藻与单甲眯的相互作用,采用评价化学品对藻类毒性的标准实验方法,得出了单甲眯抑制斜生栅藻生长的%h一EC。。为6.smg/L。实验结果还表明,在单甲眯浓度分别为2、4和smg/L下,斜生栅藻都不具备降解单甲眯的能力。图2表2参6X592 9701601玻璃纤维附载Ti02光催化降解有机磷农药/陈士夫…(郑州工学院化工系)//环境科学/中科院生态环境研究中心一1996,17(4)一33~35 环信X一5 研究以四异丙… 相似文献
5.
铜绿微囊藻和斜生栅藻生长的氮营养动力学特征 总被引:9,自引:1,他引:8
利用批量培养试验比较研究了氮限制条件下铜绿微囊藻(Microcystis aerugiuosa)和斜生栅藻(Scendesmus obliquus)对氮的生长反应,并应用Monod方程计算了2种藻的营养动力学参数(μmax和Ks). 结果表明,ρ(氮)为0~2.00 mg/L时铜绿微囊藻比增长率快速增长;ρ(氮)为0~4.00 mg/L时斜生栅藻比增长率快速增长. 铜绿微囊藻的最大比增长率(μmax)为0.23 d-1,半饱和常数(Ks)为0.14 mg/L;斜生栅藻的μmax为0.41 d-1,Ks为0.24 mg/L. 根据生长动力学参数可以预测,当氮缺乏时,铜绿微囊藻容易形成优势,当氮丰富时,斜生栅藻容易形成优势. 相似文献
6.
7.
研究了邻苯二甲酸二甲酯在臭氧氧化和二氧化钛光催化氧化两种条件下的氧化降解历程,采用胶束电动毛细管色谱技术对邻苯二甲酸二甲酯降解反应的中间产物和终产物进行踊跃分析,初步认为,臭氧氧化邻苯二甲酸二甲酯时,首先是侧链反应,生成邻苯二甲酸,然后再进一步氧化降解,而TiO2光催化氧化时,则为自由基直接攻击苯环,开环生成链状化合物,最终降解为CO2和H2O。 相似文献
8.
9.
研究了海河河口水在不同条件下对三丁基锡(TBT)的降解作用。不同条件下TBT的降解半衰期为5.7天~84.5天。提高温度、光照和加入营养盐和腐殖酸均加快TBT的降解,说明TBT的降解与生物作用有关。为此,进一步研究了两种藻——淡水斜生栅藻(Scenedesmusobliquus)和生于河口地区的扁藻(Platymonassp.)及藻液中细菌群落对TBT的降解作用。结果表明,光降解是微乎其微的。细菌群落对TBT有一定的降解作用,栅藻、扁藻中的细菌群落对TBT降解半衰期分别为54.3天和20.2天。藻类对TBT的降解速度比细菌快很多,是TBT降解的主要因素,栅藻、扁藻对TBT降解半衰期分别为5.2天和1.7天。 相似文献
10.
《环境科学与技术》2017,(9)
该文采用长期搅拌法制备n C_(60)悬浊液,以斜生栅藻(Scenedesmus obliquus)为测试藻种,研究了n C_(60)与斜生栅藻的相互作用效应及环境因素包括p H、离子强度和天然有机物的影响。结果表明,n C_(60)对斜生栅藻的长期作用表现为先抑制后促进作用;环境因素影响n C_(60)与斜生栅藻的作用效应:离子强度和天然有机物的存在能加速n C_(60)在水中的聚集沉降,使环境中分散态n C_(60)浓度降低,促进斜生栅藻细胞生长;而p H值对两者的相互作用影响不大。综上,可知在水介质中n C_(60)的存在状态是影响n C_(60)对斜生栅藻生物毒性的主要因素。 相似文献
11.
Yan Hai 《环境科学学报(英文版)》1998,10(3):2
DimethylphthalatebiodegradationbyDunalielatertiolectaYanHai,LiuYunxiaResearchCenterforEcoEnvironmentalSciences,ChineseAcad... 相似文献
12.
Dunaliella tertiolecta has an ability to biodegrade dimethyl phthalate(DMP) was found in this study, and the average of the biodegradation rates were 11.3mg/L and 30.5mg/L per day, and the average of the phthalic acid (PA) production rates were 1.5 mg/L and 3.6 mg/L per day, for initial 100mg/L and 300 mg/L DMP,respectively. The larger amount of accumulation by D. tertiolecta under higher DMP concentration may be responsible for the increase of biodegradation rate, and one of products of DMP biodegradation by D. Tertiolecta may be PA. By fitting the process of DMP biodegradation by D. Tertiolecta with a kinetic equation newly suggested, the standard deviations between calculated and observedvalues were 2.5 mg/L and 5.7 mg/L, respectively. 相似文献
13.
耐低温菌JH-9降解苯胺的动力学研究 总被引:1,自引:0,他引:1
研究耐低温菌JH-9在低温(10 ℃)条件下对不同初始ρ(苯胺)的生物降解情况,并采用反应动力学方程(Monod方程和Haldane方程)拟合其降解过程. 结果表明,菌株JH-9在低温下可降解苯胺,当菌体初始质量浓度一定时,苯胺降解率及平均降解速率主要与初始ρ(苯胺)有关. 初始ρ(苯胺)较低时(<550 mg/L),其在120 h内可完全降解,且平均降解速率随着初始ρ(苯胺)的增加而升高,菌体降解过程中没有出现苯胺毒性抑制作用,遵循Monod方程;当初始ρ(苯胺)较高时(>550 mg/L),苯胺降解率及降解速率均有所下降,由于初始ρ(苯胺)过高对菌体产生了抑制作用,其降解过程以基质抑制型的Haldane方程为主. 相似文献
14.
酒精废水消化液生物硝化和脱氮试验 总被引:1,自引:0,他引:1
酒精糟液厌氧消化液CODCr浓度为3500~4300mgL,BOD5浓度为1500~2100mgL,TN浓度为400~700mgL,NH3N浓度为300~600mgL。采用SBR反应器对该消化液进行生物脱氮试验,对反应器的有机负荷、氨氮负荷、脱氮效果、脱氮过程中氮形态的变化以及碳源提供等进行了研究分析。试验结果表明,当消化液碳源充足,SBR充水比λ=0.35,缺氧时间3h以及BOD5污泥负荷0.26~0.32kgkg·d条件下,SBR处理出水CODCr598~632mgL,BOD560~100mgL,氨氮6~9mgL,总氮200~216mgL,总氮去除率为60%左右。该处理系统中缺氧段反应时间仅为3h,却承担70%~75%的CODCr总去除负荷,显著提高了该系统的有机负荷和氨氮负荷。在消化液碳源不足的条件下,可投加乙酸钠作为生物脱氮的外碳源,投加量宜为500mgL。 相似文献
15.
16.
表面活性剂对极性有机物在沉积物上吸附的影响 总被引:7,自引:2,他引:5
研究了苯酚、苯胺和对硝基苯酚在沉积物-十二烷基苯磺酸钠(SDBS)体系中的分配特性.结果表明200mg/L和1200mg/L的SDBS存在下,苯胺和对硝基苯酚的沉积物-水分配系数均增大,分配作用的增大倍数与有机物的Kow呈正相关;苯酚的分配系数则因表面活性剂存在浓度的不同分别增大和减小.十二烷基硫酸钠(SDS)、Triton X-100(TX100)和Brij30存在下,苯酚等温吸附实验表明:表面活性剂浓度约低于其临界胶束浓度(CMC)时,苯酚的吸附量增大;表面活性剂浓度约高于其CMC时,苯酚的吸附量比纯水中的吸附量小. 相似文献
17.
Anoxic biodegradation of dimethyl phthalate (DMP) by activated sludge cultures under nitrate-reducing conditions 总被引:3,自引:0,他引:3
Worldwide extensive use of plasticized plastics has resulted in phthalates pollution in different environment. Nitrates from industry and agriculture are also widely disseminated in the soils, natural waters and wastewaters. Dimethyl phthalate (DMP) biodegradation by activated sludge cultures under nitrate-reducing conditions was investigated. Under one optimized condition, DMP was biodegraded from 102.20 mg/L to undetectable level in 56 h under anoxic conditions and its reaction fitted well with the first-order kinetics. Using the high-performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC-MS) analysis, mono-methyl phthalate (MMP) and phthalic acid (PA) were detected as the major intermediates of DMP biodegradation. When combined with the determination of chemical oxygen demand (CODCr) removal capacity and pH, DMP was found to be mineralized completely under anoxic conditions. The biodegradation pathway was proposed as DMP → MMP → PA → … → CO2 H2O.The molar ratio of DMP to nitrate consumed was found to be 9.0:1, which agrees well with the theoretical stoichiometric values of DMP biodegradation by nitrate-reducing bacteria. The results of the non-linear simulation showed that the optimum pH and temperature for the degradation were 7.56 and 31.4℃, respectively. 相似文献
18.
Alkylphenols (APs), the breakdown products of alkylphenol polyethoxylates that are widely used as surfactants, have been proven to exert estrogenic effects. With industrial development, higher concentrations of APs are discharged into aquatic environments. Nonylphenol (NP), the most noxious AP, is included in the blacklist of several countries. The toxicity of NP to the alga Cyclotella caspia and the biodegradation of NP by C. caspia were studied in the laboratory. The median effective concentration at 96 hr (96 hr EC50 ) of NP for C. caspia was found to be 0.18 mg/L. Five toxicity and three degradation indices were selected for toxicity and biodegradation experiments, respectively, in five or three concentrations of NP set by the 96 hr EC50 of NP. The algal growth rate and chlorophyll a contents decreased as NP concentration increased. The main manifestations of morphological deformity of the cells included volume expansion and the presence of cytoplasmic inclusions (lipid droplets). The abnormality rate of the cells increased with NP concentration and time, and was 100% at 0.22 and 0.26 mg/L of NP after 192 hr of culture. Superoxide dismutase activity initially increased and then declined at a higher NP toxicity of greater than 0.18 mg/L. After 192 hr of culture, the biodegradation rates of NP by C. caspia with initial concentrations of 0.14, 0.18, and 0.22 mg/L were 37.7%, 31.7%, and 6.5%, respectively. The kinetic equation of C. caspia biodegradation on NP was correlated with algal growth rate and initial NP concentration. 相似文献
19.
The phenol and m-cresol biodegradations were studied using the mutant strain CTM 2 obtained by the He-Ne laser irradiation on wild-type Candida tropicalis. The results showed that C. tropicalis exhibited the increased capacity of phenolic compounds degradation after laser irradiation. It could degrade 2600 mg/L phenol and 300 mg/L m-cresol by 5% inoculum concentration, respectively. In the dual-substrate biodegradation system, 0-500 mg/L phenol could accelerate m-cresol biodegradation, and 300 mg/L m-cresol could be completely utilized within 46 hr at the presence of 350 mg/L phenol. Besides, the maximum biodegradation of m-cresol could reach 350 mg/L with 80 mg/L phenol within 61 hr. Obviously, phenol, as a growth substrate, could promote CTM 2 to degrade m-cresol, and was always preferentially utilized as carbon source. Comparatively, low-concentration m-cresol could result in a great inhibition on phenol degradation. In addition, the kinetic behaviors of cell growth and substrate biodegradation were described by kinetic model proposed in our laboratory. 相似文献
20.
The phenol and m-cresol biodegradations were studied using the mutant strain CTM 2 obtained by the He-Ne laser irradiation on
wild-type Candida tropicalis. The results showed that C. tropicalis exhibited the increased capacity of phenolic compounds degradation
after laser irradiation. It could degrade 2600 mg/L phenol and 300 mg/L m-cresol by 5% inoculum concentration, respectively. In the
dual-substrate biodegradation system, 0–500 mg/L phenol could accelerate m-cresol biodegradation, and 300 mg/L m-cresol could be
completely utilized within 46 hr at the presence of 350 mg/L phenol. Besides, the maximum biodegradation of m-cresol could reach
350 mg/L with 80 mg/L phenol within 61 hr. Obviously, phenol, as a growth substrate, could promote CTM 2 to degrade m-cresol,
and was always preferentially utilized as carbon source. Comparatively, low-concentration m-cresol could result in a great inhibition
on phenol degradation. In addition, the kinetic behaviors of cell growth and substrate biodegradation were described by kinetic model
proposed in our laboratory. 相似文献