电催化氧化技术处理制革综合废水

选择DSA电极中的钛基掺硼金钢石膜电极(Ti/BDD),用于制革综合废水的电催化氧化处理研究,考察了在不同的电流密度、电压、电解质、pH值和电解时间等因素对COD去除率和电流效率的影响。结果表明,控制电流密度为30mA/cm2,电压为8.0 V,电解质(NaCl)浓度为2.0 g/L,pH为4.0,电催化氧化处理2 h后,废水的COD和NH4+-N的去除率分别达到了83.6%和90.3%,BOD/COD为0.45,比能耗为35.34 kWh/kg COD,电流效率为37%。     

NaClO_2/氨水溶液同时脱除SO_2和NO的热力学研究

利用化学热力学基本原理分别对NaClO2/氨水溶液同时脱除SO2、NO的反应过程中摩尔反应吉布斯自由能变、摩尔反应焓变、化学反应平衡常数以及化学反应达到平衡时的SO2和NO的分压力进行了计算,结果表明：利用NaClO2/氨水溶液同时脱除SO2、NO是可行的,且SO2和NO的脱除效率几乎可以达到100%。     

Determination of antibiotics in sewage from hospitals, nursery and slaughter house, wastewater treatment plant and source water in Chongqing region of Three Gorge Reservoir in China

Sewage samples from 4 hospitals, 1 nursery, 1 slaughter house, 1 wastewater treatment plant and 5 source water samples of Chongqing region of Three Gorge Reservoir were analyzed for macrolide, lincosamide, trimethoprim, fluorouinolone, sulfonamide and tetracycline antibiotics by online solid-phase extraction and liquid chromatography-tandem mass spectrometry. Results showed that the concentration of ofloxacin (OFX) in hospital was the highest among all water environments ranged from 1.660 μg/L to 4.240 μg/L and norfloxacin (NOR, 0.136-1.620 μg/L), ciproflaxacin (CIP, ranged from 0.011 μg/L to 0.136 μg/L), trimethoprim (TMP, 0.061-0.174 μg/L) were commonly detected. Removal range of antibiotics in the wastewater treatment plant was 18-100% and the removal ratio of tylosin, oxytetracycline and tetracycline were 100%. Relatively higher removal efficiencies were observed for tylosin (TYL), oxytetracycline (OXY) and tetracycline (TET)(100%), while lower removal efficiencies were observed for Trimethoprim (TMP, 1%), Epi-iso-chlorotetracycline (EICIC, 18%) and Erythromycin-H₂O (ERY-H₂O, 24%). Antibiotics were removed more efficiently in primary treatment compared with those in secondary treatment.     

Perfluorochemicals in wastewater treatment plants and sediments in Hong Kong

The study reported in this paper examined the concentrations of nineteen perfluorochemicals (PFCs), including perfluoroalkyl sulfonates, carboxylates, and sulfonamides in samples collected from Hong Kong wastewater treatment plants (WWTPs) and sediments. The study was the first to use an external isolator column to assist in the quantification of PFCs in environmental samples without having to make internal modifications to a liquid chromatography system. Perfluorooctanesulfonate was found to be the dominant PFC pollutant in Hong Kong, and the WWTP sludge was the major sink of PFCs discharged from the urban areas. Compared to discharge influenced by industrial activities, much less perfluorooctanoate was found in waste streams. The significantly lower level of perfluorodecanesulfonate in WWTP sludge reflects the important influence of consumer products on PFC distribution. The dominance of even-chain length perfluoroalkyl carboxylates in all of the WWTP sludge samples investigated further suggests the strong aerobic degradation of fluorotelomer alcohols in WWTPs.     

Effects of temperature and fertilization on total vs. active bacterial communities exposed to crude and diesel oil pollution in NW Mediterranean Sea

The dynamics of total and active microbial communities were studied in seawater microcosms amended with crude or diesel oil at different temperatures (25, 10 and 4 °C) in the presence/absence of organic fertilization (Inipol EAP 22). Total and hydrocarbon-degrading microbes were enumerated by fluorescence microscopy and Most Probable Number (MPN) method, respectively. Total (16S rDNA-based) vs. active (16S rRNA) bacterial community structure was monitored by Capillary-Electrophoresis Single Strand Conformation Polymorphism (CE-SSCP) fingerprinting. Hydrocarbons were analyzed after 12 weeks of incubation by gas chromatography-mass spectrometry. Total and hydrocarbon-degrading microbial counts were highly influenced by fertilization while no important differences were observed between temperatures. Higher biodegradation levels were observed in fertilized microcosms. Temperature and fertilization induced changes in structure of total bacterial communities. However, fertilization showed a more important effect on active bacterial structure. The calculation of Simpson's diversity index showed similar trends among temperatures whereas fertilization reduced diversity index of both total and active bacterial communities.     

Tissue S/N ratios and stable isotopes (δS and δN) of epilithic mosses (Haplocladium microphyllum) for showing air pollution in urban cities in Southern China

In urban cities in Southern China, the tissue S/N ratios of epilithic mosses (Haplocladium microphyllum), varied widely from 0.11 to 0.19, are strongly related to some atmospheric chemical parameters (e.g. rainwater SO₄²⁻/NH₄⁺ ratios, each people SO₂ emission). If tissue S/N ratios in the healthy moss species tend to maintain a constant ratio of 0.15 in unpolluted area, our study cities can be divided into two classes: class I (S/N > 0.15, S excess) and class II (S/N < 0.15, N excess), possibly indicative of stronger industrial activity and higher density of population, respectively. Mosses in all these cities obtained S and N from rainwater at a similar ratio. Sulphur and N isotope ratios in mosses are found significantly linearly correlated with local coal δ³⁴S and NH₄⁺-N wet deposition, respectively, indicating that local coal and animal NH₃ are the major atmospheric S and N sources.     

Dioxins, PCBs, and HCB in soil and peat profiles from a pristine boreal catchment

The aim of this study was to explore how atmospherically derived soil pollution is affected by environmental processes at two typical boreal catchment landscape type settings: wetlands and forested areas. Measurements of hydrophobic organic compounds (HOCs) in forest soil and peat from an oligotrophic mire at various depths were performed at a remote boreal catchment in northern Sweden. HOCs in peat were evenly distributed throughout the body of the mire while levels of HOCs in the forest soil increased with increased amount of organic matter. Evaluation of HOC composition by principal component analysis (PCA) showed distinct differences between surface soils and deeper soil and peat samples. This was attributed to vertical transport, degradation and/or shifting sources over time. The calculated net vertical transport differed between surface layers (0.3%) and deeper soils (8.0%), suggesting that vertical transport conditions and processes differ in the deeper layers compared to the surface layers.     

Identification of microcystins from three collection strains of Microcystis aeruginosa

Microcystins (MCs) are toxic cyclic heptapeptides produced by various cyanobacteria genera, especially Microcystis. We identified 10 out of 12 MCs produced by three Microcystis aeruginosa strains from cyanobacteria collections, UTEX 2666, UTEX 2670 and UAM 1303, by using two analytical methods: Matrix-assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF/MS) and HPLC Photodiode Array Detector coupled to a hybrid Quadrupole Time of Flight Mass Spectrometry (HPLC-PDA-QTOF/MS). MALDI-TOF/MS failed to detect non-polar MCs, such as MC-LY and MC-LW. HPLC-QTOF/MS permitted the accurate identification of most MCs present in methanolic extracts. Besides, three new MCs, namely: [D-Glu(OCH₃)⁶, D-Asp³] MC-LAba, MC-YL and MC-YM were detected by HPLC-QTOF/MS.     

可见光响应型CuO/BiVO4的光催化活性研究

采用浸渍法制备了CuO/BiVO4光催化剂,通过X射线衍射(XRD)、热重/差示扫描量热(TG/DSC)和傅立叶红外光谱(FTIR)对其进行了表征,并在可见光照射下考察了其光催化氧化亚甲基蓝(MB)的动力学特性。结果表明,Cu的掺杂并未改变BiVO4的晶型结构;Cu(NO3)2/BiVO4在热处理(30～300℃)过程中,NO3-已经完全分解,Cu最终以CuO的形式存在于CuO/BiVO4光催化剂体系中;掺杂不同量Cu的CuO/BiVO4中的Cu2+/Bi+(摩尔比)实测值与理论值相近,该系列光催化剂的合成过程具有较高的可信度;在可见光照射下,CuO/BiVO4光催化降解MB反应符合表观一级反应动力学特征;当Cu2+/Bi+为0.050时,反应动力学速率常数(k)达到最高值(0.4334h-1),此时的k比单体BiVO4作用下的提高了1.04倍;由于异质结的存在,CuO/BiVO4与单体BiVO4相比,电子和空穴的利用率大大增加,使得CuO/BiVO4的光催化活性较单体BiVO4有了大幅度提高。     

Fe^3＋掺杂TiO2/凹凸棒复合材料的光催化性能

采用酸催化的溶胶-凝胶法制备了一系列Fe^3＋掺杂TiO2/凹凸棒（Fe^3＋-TiO2/ATP）复合光催化剂材料。在可见光条件下,以亚甲基蓝（MB）溶液的光催化降解反应,评价了样品的光催化性能,研究了TiO2负载量、Fe^3＋掺杂量和焙烧温度对复合材料光催化性能的影响。在单因素实验的基础上,采用正交实验设计（L25（53））优化了催化剂的制备条件。光催化实验结果表明,MB在复合材料上的光催化降解反应遵循Langmuir-Hinshelwood（L-H）动力学模型。正交实验结果表明,当TiO2负载量为15%、Fe^3＋掺杂量为0.5%和焙烧温度为550℃时,得到的复合材料对MB的光催化降解效率最佳,测得表观反应速率常数kapp为6.09×10^-3min^-1,反应4 h后MB的降解率（Dt）可达75.88%,相同实验条件下与P25（1.51×10^-3min^-1）相比较,反应速率提高了4.03倍,降解率提高了45.05%。另外,复合材料的沉降性能优于P25,易于分离,是一类有应用前景的复合光催化剂。敏世雄王芳魏立强王永生冯雷佟永纯韩玉琦