氯氰菊酯高效降解菌GF31的生长特性及其对污染土壤的修复能力

利用高效降解菌对受污土壤进行生物强化修复是提高修复效果的可行途径之一,其中降解菌的竞争力与适应性是决定强化修复过程成败的关键因素.以实验室保藏的1株氯氰菊酯高效降解菌--铜绿假单胞菌CF31为对象,开展菌株生长特性及其对污染土壤修复的实验研究.结果表明,菌株GF31生物活性高,环境适应力强,在温度15～35℃,pH值5...     

电除尘器进口矩形烟道气流分布改进的CFD模拟

应用CFD软件对某电厂电除尘器进口矩形烟道内气流分布进行数值模拟.结果表明:电除尘器原进口矩形烟道监测截面的气流分布极其不均匀,数值模拟结果与实验结果速度分布趋势比较吻合.基于此,通过多次改变电除尘器进口矩形烟道内导流板的数量、位置、尺寸等结构参数,使得改造后烟道监测截面风量偏差降到了±2.2%,气流分布相对均方根值均...     

电渗析在丙烯酸丁酯废水预处理中的应用

采用电渗析法预处理丙烯酸丁酯生产废水,可将废水中的有机酸盐浓缩回收,同时大大降低废水的污染物浓度.重点研究了淡水浓水初始体积比的影响,同时考察了电渗析过程中水的迁移.实验确定了淡水浓水的最佳初始体积比为5∶1,此时对COD为61 650 mg/L的废水,COD去除率可达99.5%,脱盐率在99.5%以上,同时可将废水的...     

Development of enzyme-linked immunosorbent assays for plasma vitellogenin in Chinese rare minnow (Gobiocypris rarus)

Due to the wide occurrence of endocrine disrupting chemicals in the environment, it is much of importance to develop high throughput screening method for the analysis of this kind of pollutants. Using anion-exchange membrane chromatography, vitellogenin (VTG) from the plasma of 17β-estradiol (E₂) treated Chinese rare minnow was rapidly purified within 15 min. Both polyclonal antibody (PcAb) and monoclonal antibody (McAb) against rare minnow VTG (R-VTG) were prepared in rabbit and Balb/c mice, respectively. The competitive enzyme-linked immunosorbent assays (ELISA) based on either PcAb or McAb were developed to identify and quantify R-VTG in the plasma, and these two methods showed similar characteristics. The detection limits of both assays were lower than 3 ng mL⁻¹ with the working ranges covering three magnitudes. The recovery efficiencies of PcAb and McAb based ELISA were 104.2% and 102.6%, respectively; and the intra-assay and inter-assay of these two assays were 6.2% and 9.2%, 8.6% and 12.8%, respectively. These results indicated that the described competitive ELISA methods were sensitive and valuable tools for quantifying vitellogenin in rare minnow plasma. These methods were then applied to measure R-VTG concentrations in plasma of male fish exposed to a series of E₂ concentrations. When E₂ levels were less than 10 ng L⁻¹, R-VTG levels in plasma were comparable to that in solvent control, while R-VTG levels significantly increased 15-folds and 350-folds, respectively when E₂ exposure concentrations were controlled at 10 and 50 ng L⁻¹. The high sensitivity of Chinese rare minnow to E₂ was demonstrated, making it a valuable model species to study environmental estrogens.     

Toxic effects of Hydrilla verticillata exposed to toluene, ethylbenzene and xylene and safety assessment for protecting aquatic macrophytes

Little information is available about the toxicity of toluene, ethylbenzene and xylene acting on macrophytes, and their toxicity data are rarely used in regulation and criteria decisions. The results extended the knowledge on toxic effects of toluene, ethylbenzene and xylene on aquatic plants. The responses of Hydrilla verticillata to these pollutants were investigated. Chlorophyll levels, lipid peroxidation, and antioxidant enzymes (superoxide dismutase and guaiacol peroxidase) showed diverse responses at different concentrations of toluene, ethylbenzene and xylene. The linear regression analyses were performed respectively, suggesting the concentrations of toluene, ethylbenzene and xylene expected to protect aquatic macrophytes were 7.30 mg L⁻¹, 1.15 mg L⁻¹ and 2.36 mg L⁻¹, respectively. This study emphasized that aquatic plants are also sensitive to organic pollutants as fishes and zooplanktons, indicating that macrophytes could be helpful in predicting the toxicity of these pollutants and should be considered in regulation and criteria decisions for aquatic environment protection.     

Transport of copper as affected by titania nanoparticles in soil columns

The effects of TiO₂ nanoparticles on the transport of Cu through four different soil columns were studied. For two soils (HB and DX), TiO₂ nanoparticles acted as a Cu carrier and facilitated the transport of Cu. For a third soil (BJ) TiO₂ nanoparticles also facilitated Cu transport but to a much lesser degree, but for a fourth soil (HLJ) TiO₂ nanoparticles retarded the transport of Cu. Linear correlation analysis indicated that soil properties rather than sorption capacities for Cu primary governed whether TiO₂ nanoparticles-facilitated Cu transport. The TiO₂-associated Cu of outflow in the Cu-contaminated soil columns was significantly positively correlated with soil pH and negatively correlated with CEC and DOC. During passage through the soil columns 46.6-99.9% of Cu initially adsorbed onto TiO₂ could be “stripped” from nanoparticles depending on soil, where Cu desorption from TiO₂ nanoparticles increased with decreasing flow velocity and soil pH.     

Composition analysis and application of degradation products of whole feathers through a large scale of fermentation

Purpose

Feathers are one of the most abundant bioresources. They are discarded as waste in most cases and could cause environmental pollution. On the other hand, keratin constituted by amino acids is the main component of feathers. In this article, we reported on biorefined feathers and integrants and application of degraded products.

Materials and methods

The fermentation of whole chicken feathers with Stenotrophomonas maltophilia DHHJ in a scale-up of a 5-L bioreactor was investigated in this article. The fermentation process was controlled at 0.08 MPa pressure, 2.5 L/min airflow, and 300 rpm as 100% oxygen saturation level, 40°C, and pH 7.8.

Results

Feathers were almost completely degraded in the tested fermentation reaction with the following conditions: 80 g of whole feathers in 3 L fermentation broth for 72 h, seed age of 16 h, 100 mL inoculation amount, and 50% oxygen saturation level. The degraded products contain 397.1 mg/L soluble protein that has mass weight ranging from 10 to 160 kD, 336.9 mg/L amino acids, and many kinds of metal ions. The fermentation broth was evaluated as leaf fertilizer and found to increase plant growth to 82% or 66% for two- or fourfold dilutions, respectively. In addition, in a hair care assay, the broth showed a hair protective function by increasing weight, flexibility, and strength of the treated hair.

Conclusions

The whole feathers were degraded completely by S. maltophilia DHHJ. The degraded product includes many factors to life, such as peptides, amino acids, and mineral elements. It could be applied as leaf fertilizer and hair care product.     

Quantifying air pollution attenuation within urban parks: an experimental approach in Shanghai, China

Parks with various types of vegetations played an important role in ameliorating air quality in urban areas. However, the attenuation effect of urban vegetation on levels of air pollution was rarely been experimentally estimated. This study, using seasonal monitoring data of total suspended particles (TSP), sulfur dioxide (SO(2)) and nitrogen dioxide (NO(2)) from six parks in Pudong District, Shanghai, China, demonstrated vegetations in parks can remove large amount of airborne pollutants. In addition, crown volume coverage (CVC) was introduced to characterize vegetation conditions in parks and a mixed-effects model indicated that CVC and the pollution diffusion distance were key predictors influencing pollutants removal rate. Therefore, it could be estimated by regression analysis that in summer, urban vegetations in Pudong District could contribute to 9.1% of TSP removal, 5.3% of SO(2) and 2.6% of NO(2). The results could be considered for a better park planning and improving air quality.     

净化SO2的生物膜填料塔中微生物类群分析

对净化废气中SO2的生物膜填料塔内的微生物进行了分离纯化并做鉴定,得到一株嗜酸性氧化硫硫杆菌（Acidithiobacillus thiooxidans IEL001）和一株分类地位非常接近链二孢属（Bispora sp.）的极端嗜酸真菌IEL002,生物膜填料塔内的极端酸性环境和有机营养的缺乏导致生物膜上的微生物种类较为单一,多样性程度不高。本研究还发现IEL002自身并不能氧化单质硫,但它能促进Acidithiobacillus thiooxidans IEL001对单质硫的氧化。     

Growth responses of the newly-discovered Cd-hyperaccumulator Rorippa globosa and its accumulation characteristics of Cd and As under joint stress of Cd and As

Rorippa globosa has been identified as a newly-found Cd-hyperaccumulating species. In the present study, growth responses of Rorippa globosa and its accumulation characteristics of Cd and As were examined under joint stress of Cd and As. The results showed that Cd and As had an antagonistic effect on enhancing the growth of Rorippa globosa plants and Cd uptake and accumulation under the low concentration Cd and As treatments. When the concentration of Cd in the soil was 10 mg/kg and the concentration of As was 50 mg/kg, the highest growing height of the plant was up to 35.9 cm and the dry weight of the shoots was up to 2.2 g/pot, respectively. Meanwhile, the accumulation of Cd in the leaves under the joint stress was higher than that at the same level under single Cd pollution. However, there were synergic adverse effects on plant growth and Cd uptake under the combined pollution from a high concentration of Cd and As. Meanwhile, the accumulation of As in the roots was greater than that in the shoots, the translocation factor (TF) was ?0.3 and the bioaccumulation factor (BF) was ?0.6, thus showing that Rorippa globosa had an excluding effect on As uptake. These results confirmed that Rorippa globosa had a strong tolerant ability to the joint stress of Cd and As, and the potential for phytoremediation of soils contaminated by Cd and As.