膜与活性炭组合工艺处理天然水的研究进展

活性炭吸附作为膜分离技术处理天然水的预处理,可以有效去除水中膜本身难以去除的低分子溶解性有机物,减少三卤甲烷等物的生成,同时减轻膜的污染。阐述了活性炭和膜技术组合工艺处理天然水的研究进展。     

环境分析化学的一个重要方向—形态分析的发展

结合一些典型环境污染研究的实例,重点概述了近年来国内在溶解金属的形态分析;固体形态分析;有机金属化合物的形态分析;以及非金属元素形态分析诸方面的进展。提出了当前应开展的主要研究课题。     

氧化沟污水处理技术在炼油厂的实际应用

本文简明地阐述了氧化沟污水处理技术的工艺原理及特点，着重指出了该工艺中溶解氧实时控制的重要性，使沧州炼油厂污水处理效果有了明显提高     

活性污泥数学模型中异养菌产率系数测定方法的研究

采用间歇活性污泥法和呼吸计量法测定活性污泥数学模型中异养菌产率系数.研究结果表明,间歇活性污泥法测定结果受试验控制条件特别是污泥有机负荷的影响非常大,且试验周期比较长;人工配水条件下,呼吸计量法测定异氧菌产率系数(YH)在0.71以上,比活性污泥数学模型推荐值高,其结果与底物性质有关,该方法准确性高,重现性良好.     

S–O–C isotopic picture of sulphate–methane–carbonate system in freshwater lakes from Poland. A review

Microbial oxidation of organic compounds (including methane), in freshwater sediments, may result in precipitation of carbonates, which may become an important geochemical archive of paleoenvironmental variations. Most probably low δ¹³C value in calcite in eutrophic systems results from an advanced oxidation of organic compounds in turbulent or/and sulphate-rich conditions. Likewise, high δ¹³C value in calcite from organic-rich sediments may evidence low redox potential of the freshwater system. Oxidation of methane and organic matter results in significant isotope effects in sulphates dissolved in water. Therefore, to better understand the origin of carbon isotope signal in carbonates, concentration and stable isotope measurements in dissolved sulphate (water column), bubble methane and calcite (freshwater sediments) have been carried out in 24 lakes, 2 ponds and 4 rivers in Poland. The highest concentration of sulphate has been detected in rivers (85.47 SO₄ ²⁻ mg/l) and an artificial lake (70.30 SO₄ ²⁻ mg/l) located in the extremely SO₄ ²⁻-polluted region called the “Black Triangle”. The lowest concentration of sulphate is found in dystrophic and mountain lakes (from 0.5 SO₄ ²⁻ to about 3 mg/l). The lowest δ³⁴S(SO₄ ²⁻) and δ¹⁸O(SO₄ ²⁻) values occur in unpolluted lakes in eastern Poland (−0.94 and 1.38‰, respectively). The highest S and O isotopic ratios are found in a polluted lake in western Poland (δ¹⁴S(SO₄ ²)=12.95‰) and in a dystrophic lake in eastern Poland (δ¹⁸O(SO₄ ²) = 16.15‰) respectively. It is proposed that δ³⁴SO₄ ²⁻ and (¹⁸O(SO₄ ²⁻) values in lakes represent a good tool to assess and quantify anthropogenic impact by acid precipitation and to monitor variations in the trophic state and redox processes controlled by biodegradation of organic compounds in sediments and water column. In general, increasing depth (up to 12 m) of the water column is associated with decreasing trend the δ¹³C(CH₄) value from about –35 to about –78‰. However, δ¹³C value in sedimentary calcite (δ¹³C vary from –10 to 0.5‰) shows opposite trends as compared to the corresponding methane. This is probably due to redox processes and distribution of heavy isotopes between methane and calcite. Likewise, turbulent water (river) show high δ¹³C value in methane and low δ¹³C value in calcite—this is probably due to an enhanced oxidation of methane producing ¹³C-depleted CO₂. In contrast to clean lakes, it is observed that an increase of the δ¹³C(CH₄) value occurs with increasing depth of the water column in a strongly SO₄ ²⁻-contaminated lake. This is probably due to a loss of biological buffering potential of the lake accompanied by an active oxidation of methane precursors.     

A cost worth paying: energetically expensive interactions with males protect females from intrasexual aggression

When approached by males, females of the Amarillo fish (Girardinichthys multiradiatus) perform a behaviour called vibration or they are aggressively challenged. We quantified vibration and assessed whether it compromises the rate of feeding attempts in dyads kept in outdoor enclosures. Male approaches resulted in female vibration and in a reduced feeding rate. Vibration was not evoked by female–female aggression, which was frequent and always ended in the subordinate fleeing from the dominant female. Using a closed respirometer we found that vibration is costly; oxygen consumption of females was greater in the presence of a male (which evoked vibration) than in the presence of a non-familiar female (when no vibration occurred). By recording interactions of females confined in aquaria in the presence and in the absence of males, we confirmed that escaping is the only available response to deal with female aggression. Females kept without males participated in frequent aggressive (even lethal) interactions that did not abate while the subordinate female was in sight of the dominant, and which caused premature births and injuries. Yet in the alternative treatment aggression ceased when a male approached, prompting vibration in both females. Thus, in the Amarillo, in as much as it evokes energetically costly female vibrations, male courtship is an expression of sexual conflict. However, in the absence of males, frequent female aggression potentially annuls the benefits of not vibrating. We propose that a complete appraisal of the consequences of sexual conflict must include an assessment of the costs imposed by intra-sexual interactions.     

微电解工艺处理染料工业废水研究

该文研究了采用微电解工艺处理染料工业废水.经过微电解工艺处理的染料工业废水色度和化学需氧量(COD)去除率分别为93.94%和64.62%.废水的可生化性提高,生化速率常数K从0.02876提高到0.04754.微电解工艺预处理该染料工业废水的吨水运行成本为0.91元.     

苏州河底泥的耗氧量

对苏州河底泥耗氧量(SOD)的实验测定结果表明,苏州河底泥(北新泾下游)的夏季耗氧强度是冬季的6倍,最大强度发生在武宁路河段,达7500mg/m2     

底泥耗氧速率的测定方法比较

在对实验室法和现场法测定底泥耗氧速度（SOD）的步骤和操作参数综述中，对于实验室测定法。从底泥采样，测定容器，实验底泥厚度，上覆水，测定培养条件，溶解氧测定方法，溶解氧测定时间和测定间隔，空白样的测定以及SOD的计算等方面作了介绍；对于现场测定法，从测定容器，测定水力条件，溶解氧测定方法，空白水样的测定，溶解氧测定时间和测定间隔，SOD的计算方法等方面作了介绍，最后在原理，技术和费用上对以上2种方法加以比较。     

Effect of dissolved oxygen on methane production from bottom sediment in a eutrophic stratified lake

Clarifying the role of sulfate and dissolved oxygen (DO) in methane production may allow for precise and accurate modeling of methane emissions in eutrophic lakes. We conducted field observations of sulfate, methane, and DO concentrations in Lake Abashiri, a typical brackish and eutrophic lake in a cold region, to develop a DO-based method for quantitively estimating methane production in a eutrophic lake and analyzed the results. We found that sulfate concentrations decreased rapidly from 900.0 mg/L in water overlying the sediments to nearly 0.0 mg/L in the bottom sediment. Methane production was almost uniform across sediment depths of 0.05 to 0.25 m, ranging from 1400 to 1800 µmol/m²/day. Also, methane production was found to be a function of DO concentrations in water overlying the bottom and could be modeled by a logistic function: constant production at 1,400 µmol/m²/day for DO concentrations of 0.0 to 3.0 mg/L, rapidly decreasing to 0 µmol/m²/day for DO concentrations of 3.0 to 6.0 mg/L. This methane model was verified using a simple one-dimensional numerical model that showed good agreement with field observations. Our results thus suggest that the proposed methane model reduces uncertainty in estimating methane production in a eutrophic lake.