油田回注水中优势硫酸盐还原菌的分离鉴定与生理特性研究

从胜利油田回注水中筛选得到一株硫酸盐还原菌,命名为zsz1209。经过16SrDNA序列分析,鉴定zsz1209为梭菌属（Clostridium）。实验研究了zsz109的生理特性,并对通过调节环境pH来抑制菌株zsz1209生长繁殖的可行性进行了探讨。实验结果表明：菌株zsz1209的理想碳源为乙酸钠,在30～60℃之间可较好地生长;SOi浓度低至50mg／L时,生长未受到明显抑制。当培养环境pH高至8．5～9．0或低至3．5～4．0时,检测菌株zsz1209对SO4^2-和碳源（COD）的利用情况,发现zsz1209的生长受到明显抑制,结果表明利用改变环境pH来抑制微生物对油田的腐蚀具有可行性。     

初始pH值对磷酸盐还原除磷的影响研究

以超高盐（盐度7％,以NaCI计）高磷榨菜废水为研究对象,考察了初始pH值对磷酸盐还原进程的影响。实验结果表明,初始pH值对磷酸盐还原除磷效能影响显著。初始pH为8时,磷酸盐还原除磷率达到最高,平均值为65．45％。同时,初始pH值还会影响污泥中活性磷的形成以及基体对磷化氢的吸附。此外,偏碱性有利于磷形态转化,且BD-P（主要是一些可溶性的、还原性强的、带有Fe-P化合物的集合）含量的高低调控着生物膜内间隙水中溶解态可反应性磷（DRP）和可还原水溶态磷（RSP）含量,最终决定着磷酸盐还原进程。随着初始pH值的升高,污泥对磷化氢的吸附能力降低导致污泥中结合态磷化氢（MBP）含量不断减少。     

pH、盐度对微生物还原硫酸盐的影响研究

采用厌氧生物处理工艺,研究了在不同盐度下pH连续降低对硫酸盐还原和有机物去除率的影响。实验结果表明,硫酸盐还原菌有很强的适应pH变化的能力,在pH值达到4以下仍有60％的硫酸盐去除率。NaCl浓度由4g／L增加到50g／L抑制了各厌氧菌的活性,导致硫酸盐和有机物去除率的下降,但硫酸盐还原菌耐受性高于产甲烷菌等其他厌氧菌,在NaCl浓度为50g／L下,硫酸盐去除率能达到50％,而有机物去除率则低于30％。qRT—PCR表明了系统菌落中SRB随着环境的变化情况与化学指标结果相一致,该反应器体系中SRB在整个厌氧菌群落中只占了很小部分。     

Atmospheric fate of non-volatile and ionizable compounds

A modified version of the Multimedia Activity Model for Ionics MAMI, including two-layered atmosphere, air-water interface partitioning, intermittent rainfall and variable cloud coverage was developed to simulate the atmospheric fate of ten low volatility or ionizable organic chemicals. Probabilistic simulations describing the uncertainty of substance and environmental input properties were run to evaluate the impact of atmospheric parameters, ionization and air-water (or air-ice) interface enrichment.The rate of degradation and the concentration of OH radicals, the duration of dry and wet periods, and the parameters describing air-water partitioning (K_AW and temperature) and ionization (pK_a and pH) are the key parameters determining the potential for long range transport. Wet deposition is an important removal process, but its efficiency is limited, primarily by the duration of the dry period between precipitation events.Given the underlying model assumptions, the presence of clouds contributes to the higher persistence in the troposphere because of the capacity of cloud water to accumulate and transport non-volatile (e.g. 2,4-D) and surface-active chemicals (e.g. PFOA). This limits the efficiency of wet deposition from the troposphere enhancing long-range transport.     

Contamination of nonylphenolic compounds in creek water, wastewater treatment plant effluents, and sediments from Lake Shihwa and vicinity, Korea: comparison with fecal pollution

Nonylphenolic compounds (NPs), coprostanol (COP), and cholestanol, major contaminants in industrial and domestic wastewaters, were analyzed in creek water, wastewater treatment plant (WWTP) effluent, and sediment samples from artificial Lake Shihwa and its vicinity, one of the most industrialized regions in Korea. We also determined mass discharge of NPs and COP, a fecal sterol, into the lake, to understand the linkage between discharge and sediment contamination. Total NP (the sum of nonylphenol, and nonylphenol mono- and di-ethoxylates) were 0.32-875 μg L⁻¹ in creeks, 0.61-87.0 μg L⁻¹ in WWTP effluents, and 29.3-230 μg g⁻¹ TOC in sediments. Concentrations of COP were 0.09-19.0 μg L⁻¹ in creeks, 0.11-44.0 μg L⁻¹ in WWTP effluents, and 2.51-438 μg g⁻¹ TOC in sediments. The spatial distributions of NPs in creeks and sediments from the inshore region were different from those of COP, suggesting that Lake Shihwa contamination patterns from industrial effluents differ from those from domestic effluents. The mass discharge from the combined outfall of the WWTPs, located in the offshore region, was 2.27 kg d⁻¹ for NPs and 1.00 kg d⁻¹ for COP, accounting for 91% and 95% of the total discharge into Lake Shihwa, respectively. The highest concentrations of NPs and COP in sediments were found in samples at sites near the submarine outfall of the WWTPs, indicating that the submarine outfall is an important point source of wastewater pollution in Lake Shihwa.     

The impact of nitrogen deposition on acid grasslands in the Atlantic region of Europe

A survey of 153 acid grasslands from the Atlantic biogeographic region of Europe indicates that chronic nitrogen deposition is changing plant species composition and soil and plant-tissue chemistry. Across the deposition gradient (2-44 kg N ha⁻¹ yr⁻¹) grass richness as a proportion of total species richness increased whereas forb richness decreased. Soil C:N ratio increased, but soil extractable nitrate and ammonium concentrations did not show any relationship with nitrogen deposition. The above-ground tissue nitrogen contents of three plant species were examined: Agrostis capillaris (grass), Galium saxatile (forb) and Rhytidiadelphus squarrosus (bryophyte). The tissue nitrogen content of neither vascular plant species showed any relationship with nitrogen deposition, but there was a weak positive relationship between R. squarrosus nitrogen content and nitrogen deposition. None of the species showed strong relationships between above-ground tissue N:P or C:N and nitrogen deposition, indicating that they are not good indicators of deposition rate.     

硫酸铝渣去除水中磷研究

分别以蒸馏水和太湖水为例,研究了硫酸铝渣去除水中磷的能力,并分析了其对水体Al3+、SO24-以及pH的影响.结果表明:(1)除太湖水pH为9.0、10.0两种条件外,随着磷平衡浓度的增加,硫酸铝渣除磷量趋于某一定值,其规律符合Langmuir吸附等温式;太湖水pH为9.0、10.0两种条件下,硫酸铝渣除磷量符合Fre...     

苯并三唑在土壤中的吸附特性

为了解苯并三唑(BTA)在水-土系统中的迁移转化,通过批实验方法研究了BTA在华北平原土样(GSS13)中的吸附,考察了平衡时间、土壤投加量、溶液初始p H以及共存阳离子对吸附的影响。结果表明,在初始阶段,土壤对BTA的吸附速率较快,之后随着吸附点位的减少,吸附逐渐变慢;吸附过程符合准二级反应动力学方程。土壤对BTA的平衡吸附为非线性吸附,吸附等温线为Freundlich型;随着土壤投加量的增大,单位质量土壤吸附BTA的量减少,可能原因是所选土壤对BTA的吸附存在"固体浓度效应"。溶液的p H通过改变BTA的存在形式和土壤表面的带电性而影响吸附,当溶液p H在BTA的p Ka2(8.6)附近时,土壤对BTA的吸附效果最好。此外,溶液中共存阳离子对土壤吸附BTA有不同的影响,Na+对吸附影响不明显,而不同浓度Ca2+对BTA的吸附有不同程度的促进作用。     

固定化斜生栅藻净化畜禽废水中氨氮和磷的影响因素

为探讨Cu2+、p H和流速对固定化斜生栅藻去除畜禽废水中NH+4-N、TP效果的影响,在实验室条件下模拟实际污水处理过程,并采用正交实验方案对结果进行分析。结果表明低质量浓度Cu2+(0~0.05 mg/L)改善藻的净化效果,高质量浓度Cu2+(0.50~5.00 mg/L)抑制藻的净化效果;在p H较高的条件下(p H=9),固定化斜生栅藻的净化效果明显提高;流速对结果没有明显影响。通过正交实验,得出固定化斜生栅藻去除畜禽废水中NH+4-N、TP的优化条件如下:Cu2+质量浓度为0.05 mg/L,p H为9,流速为0.3 m/s。此时NH+4-N去除率为96.11%,TP去除率为97.53%。     

酸碱度对生活垃圾焚烧厂沥滤液蒸发处理效果的影响

采用蒸发法处理城市生活垃圾焚烧厂垃圾沥滤液,着重考察了不同沥滤液初始pH值对蒸发去除COD和氨氮效果的影响,并采用GC-MS对蒸发冷凝液中有机物成分进行了分析鉴定.结果表明,生活垃圾沥滤液的初始pH对冷凝液中COD、氨氮含量及有机污染物分布产生了决定性的影响.沥滤液在酸性条件下(pH≤6)蒸发,随着pH的增加,冷凝液中COD的含量线性降低,而氨氮的含量线性增加.当沥滤液的初始pH值从6增加到11,冷凝液中COD的含量呈对数函数降低,而氨氮的含量表现出显著增加趋势.从冷凝液中鉴定出38种有机污染物,多为沸点较低的醇、酸、酚和酯类.在酸性条件下(pH=3),冷凝液中挥发性有机酸和低碳醇的相对丰度接近90％.在近中性条件下(pH=6.2),冷凝液中的有机污染物以酚、酸和杂环类化合物为主.在碱性条件下(pH =11),冷凝液中酚和杂环类化合物占比较高,而酸的含量极少.