Bioaccumulation and physiological effects of tetrabromobisphenol A in coontail Ceratophyllum demersum L

Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retardants. In the present study, the accumulation of TBBPA and its consequent biological responses were examined in coontail (Ceratophyllum demersum L.) over 14 days' exposure. Most of the TBBPA was accumulated after 4d exposure and TBBPA concentration in plant increased with increasing TBBPA concentration in growth solution (R(2)=0.99). By using electron paramagnetic resonance (EPR), we found that the TBBPA exposure significantly increased total free radicals generation in the plants. A good positive relationship (R(2)=0.99) was found between the free radicals formation and accumulation level of TBBPA in plant. Lipid peroxidation was enhanced and chlorophyll content showed declined after TBBPA exposure. The activities of superoxide dismutase (SOD), peroxidase (POD), and the contents of glutathione were also detected. The results suggest that TBBPA accumulation in C. demersum induces oxidative stress and the level of tolerance depends on the antioxidative capacity of the plants.     

庚烷与二氧化硫的光化学反应研究

研究了庚烷与二氧化硫的光化学反应,利用GC/MS对气相产物及气溶胶产物进行了定性分析,确定了部分产物：醇、酮、呋喃衍生物、有机酸、三氧化硫、一氧化碳、二氧化碳等,探讨了反应机理和反应动力学,考察了NO,NO2,O2对反应的影响。     

成都市生态城市建设的路径设计

文章结合成都市自然资源的优势和特点,依据生态原理的基本思想,从城市河流生态的保护与建设;成都绿化的生态建设与城市生态社区示范建设;城乡融合生态系统的基本设计;成都郊县市生态农业、生态聚落的建设和生态建设总体布局与功能分区等五个方面进行了具体的分析,提出了相关的设计路径和措施。     

Evaluating Controlling Factors to Ali/(Ca + Mg) Molar Ratio in Acidic Soil Water, Southern and Southwestern China: Multivariate Approach

Al_i/(Ca + Mg) molar ratio in soil water has been used as an indicator to the effects of acid deposition on terrestrial ecosystems. However, the main factors controlling this ratio have not been well documented in southern and southwestern China. In this study, we presented the variation in inorganic aluminum (Al_i) and Al_i/(Ca + Mg) molar ratio in different sites and soil horizons based on two to three years monitoring data, and evaluated the main factors controlling Al_i/(Ca + Mg) molar ratio using principle component analysis (PCA) and partial least square (PLS) regression. Monitoring data showed although Al_i/(Ca + Mg) molar ratios in most soil water were lower than assumed critical 1.0, higher molar ratios were found in some soil water at TSP and LXH site. Besides acid loading, both soil properties and soil water chemistry affected the value of Al_i/(Ca + Mg) molar ratio in soil water. Partial least square (PLS) indicated that they had different relative importance in different soil horizons. In A-horizon, soil aluminum saturation (AlS) had higher influence on Al_i/(Ca + Mg) molar ratio than soil water chemistry did; higher soil aluminum saturation (AlS) led to higher Al_i/(Ca + Mg) molar ratio in soil water. In the deeper horizons (i.e., B₁-, B₂- and BC-horizon), inorganic aluminum (Al_i) in soil water had more and more important role in regulating Al_i/(Ca + Mg) molar ratio. On regional scale, soil aluminum saturation (AlS) as well as cation exchange capacity (CEC) was the dominant factor controlling Al_i/(Ca + Mg) molar ratio. This should be paid enough attention on when making regional acid rain control policy in China.     

Polycyclic aromatic hydrocarbons in the surface sediments from Yellow River, China

Fourteen surface sediment samples were collected from Lanzhou Reach of Yellow River, China in July 2005. The concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatography equipped with a mass spectrometry detector (GC-MS). Total concentrations of the PAHs ranged from 464 to 2621 ng/g dry weight. Sediment samples with the highest PAH concentrations appeared at the downstream of Lanzhou City, where there was the biggest wastewater discharge pipeline from Lanzhou Oil Refinery Factory and Lanzhou Chemical Industry Company. Municipal sewage also contributed to the PAH contamination in the sediments. A correlation existed between the sediment organic carbon content (f(oc)) and the total PAH concentrations (r(2)=0.57), suggesting that sediment organic carbon content played an important role in controlling the PAHs levels in the sediments. According to the observed molecular indices, PAHs contamination in Lanzhou Reach of Yellow River originated both from the high-temperature pyrolytic processes and from the petrogenic source, showing a mixed PAH input pattern, which was also confirmed by the results of a principal component analysis (PCA). According to the numerical effect-based sediment quality guidelines (SQGs) of the United States, the levels of PAHs at most studied sites in Lanzhou Reach of Yellow River should not exert adverse biological effects. Although at some sites (such as S10, S12, etc.) one PAH may exceed the effects range low (ERL), individual PAH did not exceed the effects range median (ERM). The results indicated that sediments in all sites should have potential biological impact, but should have no impairment.     

氧化镁基催化吸附剂的制备及脱硝性能研究

采用共混合法制备氧化镁基催化吸附剂,通过正交实验设计找出其组分的最佳配比.利用该催化吸附剂对烟气进行脱硝实验,考察了焙烧温度、焙烧时间和床层温度对氧化镁基催化吸附剂去除NO的影响.结果表明,利用氧化镁基催化吸附剂可以对烟气进行直接催化分解脱硝,其最佳的焙烧温度和时间分别为350～500 ℃和3～4 h,脱硝率可达85%～95%.利用红外光谱(FT-IR)、X射线衍射(XRD)对脱硝处理前后的氧化镁基催化吸附剂进行了分析,探讨其脱硝的机制.     

吹脱-沸石吸附法处理荧光粉生产废水研究

研究了吹脱-沸石吸附法处理荧光粉生产废水.正交试验结果表明:氨吹脱工艺中影响NH3-N去除率因素的重要性顺序为:pH＞温度＞气液比.当pH=11、气液比(V/V)=100:1、温度T=40℃、吹脱时间t=120 min,吹脱工艺对荧光粉生产废水中NH3-N的去除率为74.46%.试验确定的沸石吸附单元较佳的工艺参数为:滤速0.04 m/min、接触时间14min、pH=7.5,吹脱-沸石吸附工艺总NH3-N去除率96.04%.试验结果表明再生沸石氨吸附性能稳定,适于高氨氮的荧光粉生产废水处理.     

含油污泥清洗剂的制备与研究

以异丙醇为溶剂,偶氮二异丁腈(AIBN)为引发剂,甲基丙烯酸(MAA)、丙烯酸丁酯(BA)和苯乙烯(St)为混合单体,通过溶液聚合的方法制备一种含油污泥清洗剂.介绍了该清洗剂的制备方法,考察了单体用量及清洗条件对清洗剂脱油性能的影响,探讨了清洗剂对含油污泥中原油不同组分的去除效率,并用红外光谱证实了所制备共聚物结构的官能团.清洗剂性能评价表明:单体用量和清洗条件均有最佳值,其中单体最佳质量比为MAA:BA:St=21:62:17,最佳清洗条件分别是:加药浓度为250 mg/L,水洗温度为60℃,反应时间为40 min;清洗剂对含油污泥中芳烃去除率最高,达93.0%.     

生物强化对MBR系统生物特性及群落结构的影响

采用高效菌强化膜生物反应器对溴氨酸废水进行处理,考察了生物强化前后系统对溴氨酸的降解能力及其内部微生物生理状态变化.并采用核糖体基因间隔序列分析技术(RISA)解析了高效菌投加前后污泥系统的群落变化.实验表明,投菌后在进水负荷增加的条件下,上清液和膜出水的溴氨酸脱色率分别约为50%和65%,相应的COD去除率分别约为25%和50%,和投菌前基本保持一致;TTC-脱氢酶活性和胞外聚合物(EPS)浓度略有波动,但是运行一段时间后即恢复到投菌前水平.群落分析表明高效菌可以在系统中稳定存在,并且不对原菌群结构造成较大影响.     

防冲刷基材生态护坡技术在边坡工程中的应用

为解决工程裸露边坡对环境的影响,在生态防护工程中引入防冲刷基材(PEB)生态护坡技术,并介绍其主要功能特点和详细实施过程,结合河南燕山水库植被护坡工程实施后植物生长、浅层防护和水土保持的监测结果,对该技术进行了全面评析。结果表明,该技术在经济、植被生长适应性、抗冲刷性方面均表现出独特的效果和优势,能较快地恢复边坡原有生态效果。该技术在类似边坡的处理上可以广泛应用。