溶解氧对活性污泥胞内贮存物和除磷性能的影响

分别以乙酸钠和葡萄糖为碳源,通过间歇实验,考察不同溶解氧(DO)浓度对厌氧-缺氧-好氧序批式反应器中活性污泥胞内贮存物聚羟基烷酸酯(PHA)、糖原和系统除磷性能的影响。实验表明:DO对以乙酸钠为碳源培养的胞内贮存物PHA和糖原影响较大,并影响污泥的除磷性能;对以葡萄糖为碳源培养的胞内物质影响较小,可能是因为细胞内存在其他类型的胞内贮存物。     

Removal of tetrachlorobisphenol A and the effects on bacterial communities in a hybrid sequencing biofilm batch reactor-constructed wetland system

SBBR-CW system was proposed to effectively treat wastewater containing TCBPA. CW unit contributed more than SBBR to the removal of TCBPA. TCBPA changed the composition and structure of bacterial community in the system. GAOs massively grew in SBBR, but did not deteriorate TP removal efficiency. Tetrachlorobisphenol A (TCBPA) released into the sewage may cause environmental pollution and health risk to human beings. The objective of this study was to investigate the removal of TCBPA and bacterial community structures in a laboratory-scale hybrid sequencing biofilm batch reactor (SBBR)-constructed wetland (CW) system. The results showed that the removal efficiency of chemical oxidation demand (COD), ammonia, total nitrogen and total phosphorus in the SBBR-CW system was 96.7%, 97.3%, 94.4%, and 88.6%, respectively. At the stable operation stage, the system obtained a 71.7%±1.8% of TCBPA removal efficiency with the influent concentration at 200 mg/L. Illumina MiSeq sequencing of 16S rRNA gene revealed that the presence of TCBPA not only reduced the bacterial diversity in the SBBR-CW system, but also altered the composition and structure of bacterial community. After the addition of TCBPA, Proteobacteria increased from 31.3% to 38.7%, while Acidobacteria and Parcubacteria decreased greatly in the SBBR. In contrast, Acidobacteria replaced Proteobacteria as the dominant phylum in the upper soils of CW. The results indicated that TCBPA stimulated the growth of GAOs in the SBBR without deteriorating the phosphorus removal due to the presence of sufficient carbon sources. The ammonia oxidizing bacteria, Nitrosomonas, and denitrification bacteria, Hyphomicrobium and Pseudomonas, were inhibited by TCBPA, resulting in a decreasing the removal efficiency of TN and ammonia.     

Simultaneous removal of arsenate and fluoride from water by AI-Fe （hydr）oxides

A1-Fe （hydr）oxides with different A1/Fe molar ratios （4：1, 1：1, 1：4, 0：1） were prepared using a co- precipitation method and were then employed for simultaneous removal of arsenate and fluoride. The 4A1 ： Fe was superior to other adsorbents for removal of arsenate and fluoride in the pH range of 5.0-9.0. The adsorption capacity of the A1-Fe （hydr）oxides for arsenate and fluoride at pH 6.50.3 increased with increasing A1 content in the adsorbents. The linear relationship between the amount of OH released from the adsorbent and the amount of arsenate or fluoride adsorbent by 4A1 ： Fe indicated that the adsorption of arsenate and fluoride by A1- Fe （hydr）oxides was realized primarily through quantita- tive ligand exchange. Moreover, there was a very good correlation between the surface hydroxyl group densities of A1-Fe （hydr）oxides and their adsorption capacities for arsenate or fluoride. The highest adsorption capacity for arsenate and fluoride by 4A1 ： Fe is mainly ascribed to its highest surface hydroxyl group density besides its largest pHpzc. The dosage of adsorbent necessary to remove arsenate and fluoride to meet the drinking water standard was mainly determined by the presence of fluoride since fluoride was generally present in groundwater at much higher concentration than arsenate.     

IC+A/O工艺在制药废水处理中的应用

针对某制药公司生产废水的特点,采用高效厌氧反应器——内循环厌氧反应器(简称IC工艺)+A/O工艺进行处理。系统稳定运行后,在进水ρ(COD)为3 500 mg/L、ρ(SS)为300 mg/L时,去除率分别达到97.9%、92.5%。处理后出水水质稳定,达到GB 8978—1996《污水综合排放标准》一级标准。     

Enzyme-linked immunosorbent assay for bisphenol A: Assay optimization and its application for surface water analysis

A range of ELISAs in indirect and direct formats for the determination of bisphenol A (BPA) was developed. Bisphenol A carboxymethyl ether (BPA-CME), (BPA-CPE) and 4,4-bis(4-hydroxyphenyl)valeric acid were coupled with bovine serum albumin (BSA) (immunogens for the production of polyclonal antibodies), ovalbumin (OVA) and horseradish peroxidase. In general, the indirect assay was more sensitive and specific than the direct one. Using heterologous combinations of immunoreagents in the indirect assay allowed to increase assay sensitivity and specificity. The highest sensitivity was obtained for the antibodies produced against a conjugate of BPA-CPE with BSA and a conjugate of 4,4-bis(4-hydroxyphenyl)valeric acid with OVA. The detection limit of BPA in phosphate buffer was 0.03?ng?mL^?1. The assay developed was also the most specific towards BPA. Maximum cross-reactivity values did not exceed 11% for 4-cumylphenol, 5% for bisphenol E and 2% for bisphenol S. Finally, the developed assay was used to analyze surface water samples spiked with known amount of BPA. The assay showed good recovery values (85–109%) for surface water with mineralization level lower than 500?mg?L^?1.     

Endocrine disruptors in the Leça River and nearby Porto Coast (NW Portugal): presence of estrogenic compounds and hypoxic conditions

The Leça River and two beaches close to the north and south margins of the estuary, nowadays an important seaport harbor, show signs of contamination. However, the chemical nature of that contamination is uncertain. Therefore, this study checked for the presence of 11 endocrine disrupting compounds (EDCs) of animal (17β-estradiol and estrone), pharmaceutical (17α-ethynylestradiol), and industrial (alkylphenols, alkylphenol ethoxylates, and bisphenol A) origins in water samples collected from six points at the river gradient and at two sites in the coastline (Atlantic Ocean). Along with the EDCs, evaluated by gas chromatography – mass spectroscopy (GC-MS) during spring, summer, and autumn, physico-chemical parameters were also assessed and particular attention was given to dissolved oxygen (DO) levels. Data showed the presence of high amounts of estrogens (up to 10?ng?L^?1 for estrone) and industrial compounds (up to 2?µg?L^?1 for the nonylphenol ethoxylates) at both river and seacoast. Along with this, clear signs of hypoxia were found in the river (DO??1 at several sampling sites). Taking into account these issues, it was concluded that there are local conditions for the occurrence of endocrine disruption in aquatic animals.     

Characterization and in vitro biological effects of ambient air PM10 from a rural,an industrial and an urban site in Sulaimani City,Iraq

Abstract

High urban atmospheric pollution is caused by economic and industrial growth, especially in developing countries. The objective of this study was to assess possible relationships between in vitro effects on human alveolar epithelial cells of source-related dust types collected at Sulaimani City (Iraq), and to determine their mineralogical and chemical composition. A passive sampler was used to collect dust particles at a rural, an industrial and an urban sampling site during July and August 2014. The samples were size-fractionated by a low-pressure impactor to obtain respirable dust with aerodynamic diameters of less than 10?µm. The dust was mainly composed of quartz and calcite. Chrysotile fibers (white asbestos) were also found at the urban site. Dust from the industrial and urban sites triggered cytotoxic and genotoxic effects in the cells, whereas only minor effects were observed for the sample from the rural site.     

Ca2+对酸性硫酸盐环境中次生铁矿物合成的影响

通过摇瓶培养试验,在富铁酸性硫酸盐环境中,探析0、50、100、200或400mg/L Ca2+加入对嗜酸性氧化亚铁硫杆菌(A. ferrooxidans)生物合成次生铁矿物过程的影响.分析了体系pH值、氧化还原电位(ORP)、Fe2+氧化率、总Fe沉淀率以及次生铁矿物矿相等相关指标的变化情况.结果表明,0~24h培养过程中,各体系pH值、ORP、Fe2+氧化率及总Fe沉淀率变化幅度基本一致.24~108h培养过程中,体系中Ca2+加入量越大,Fe2+氧化越迅速,相应总Fe沉淀率相对较高.400mg/L Ca2+的加入使得体系Fe2+在72h氧化完全,总Fe沉淀率在108h达到39.1%.0、50、100或200mg/L Ca2+ 加入的体系在24~84h培养过程中,体系Fe2+氧化速率随着Ca2+加入量逐渐增加而依次升高,并在84h Fe2+氧化完全,且在108h,相应体系总Fe沉淀率分别为27.0%、29.7%、33.9%或36.9%.不同体系所得次生铁矿物均为施氏矿物与黄铁矾的混合物.本研究结果对明晰富铁酸性硫酸盐环境钙离子调控生物成因次生铁矿物合成的影响机理有一定指导意义.     

A2O-BAF反硝化除磷工艺丝状菌膨胀的发生及控制

为了有效控制A2O-BAF反硝化除磷工艺处理实际生活污水时产生的丝状菌污泥膨胀,研究了有机负荷和冬季突然降温对丝状菌污泥膨胀的影响.结果表明:当有机负荷低于0.30kgCOD/(kgMLSS·d)时,系统中存在轻度的丝状菌污泥膨胀现象;当有机负荷高于0.55kgCOD/(kgMLSS·d)时,容易引发严重的丝状菌污泥膨胀,调节有机负荷可使丝状菌污泥膨胀得到有效控制.冬季突然降温也会导致污泥膨胀的发生,恢复温度后,污泥沉降性能恢复正常,丝状菌污泥膨胀亦得到有效控制.     

三峡水库香溪河库湾拟多甲藻的昼夜垂直迁移特性

2008年4月3日08:00—4日08:00在三峡水库香溪河库湾5个监测点对拟多甲藻(Peridiniopsis sp.)进行了24 h连续监测,以研究拟多甲藻的昼夜垂直迁移特性,并解释拟多甲藻水华表层水体表观颜色昼夜变化的原因. 结果表明:拟多甲藻在12 m水深以上水柱中存在明显的周期性昼夜垂直迁移特性,00:00—16:00拟多甲藻向表层水体迁移并聚集,最大上移速度约为2 m/h;16:00—00:00拟多甲藻向下部水体迁移,最大下移速度约为4 m/h;拟多甲藻的昼夜垂直迁移是导致拟多甲藻水华表层水体表观颜色不断变化的主要原因. 水体中各层叶绿素a质量浓度〔ρ(Chla)〕昼夜变化较大,用单层ρ(Chla)不足以评价藻类水华暴发程度;均深叶绿素a质量浓度〔ρ(A.D. Chla)〕的昼夜变化不大,能够综合表征藻类迁移水柱中藻类的现存量,可以作为河道型水库拟多甲藻水华暴发程度的评价指标.