富营养化水体的水芹菜浮床栽培试验

通过水面浮床栽培试验,研究了水培水芹菜(Oenanthe javanica)植株的生长特征、生物量的解析结构,以及水芹菜在富营养化水体中对氮、磷的吸收,水芹植株的平均鲜量为85.22 g,其中水上部分占82%,水下部分占18%,生物量分布主要集中在水上部分.其对N 、P的直接吸收分别可以达到43.63～67.46 kg/(hm2·a)和9.828～10.29 kg/(hm2·a).结果表明,水芹是一种适合在低温的情况下进行水培的植物,并对富营养化水体有良好的净化效果.     

混合酶强化剩余污泥微生物燃料电池性能

为了提高剩余污泥为燃料的微生物燃料电池(SMFC)产电性能以及污泥减量化效果,在不同的温度(40、45和50℃)研究单室无膜微生物燃料电池中酶对SMFC产电特性的强化效果.加入单一酶(蛋白酶或α-淀粉酶)的结果表明,随着温度的上升,SMFC功率密度均上升,但40℃时强化效果最明显,与加入失活酶的对照组相比分别增加198％和130％.在40℃下,混合酶比(蛋白酶浓度:淀粉酶浓度)为2∶3时,SMFC最大功率密度为776 mW/m2.随着混合酶中淀粉酶的比例提高,SMFC库伦效率逐渐增加,当混合酶比为4∶1时,CE(库伦效率)可达18.3％,同时TCOD、TSS和VSS去除率分别为70.3％、66.7％和80.4％.因此,温度相对较低时,外加酶强化效果更明显;与单种酶相比,混合酶对SMFC产电性能和污泥减量化的强化效果更显著.     

沸石-茭白复合床技术脱氮中试研究

通过模拟农村暴雨径流水质 ,开展了沸石 茭白复合床技术处理农村暴雨径流的中试研究 ,分析了在不同工况下床体中各态氮的变化规律 ,结果表明 ,该项技术应用于暴雨径流氮的控制是可行的。     

水中藻类对连续流动法测定总氮结果的影响

以天津市河道、水库为研究对象,在藻类增殖期采用连续流动法与碱性过硫酸钾消解法对水体中总氮进行比对监测,同时分析水中藻类分类和藻细胞密度。试验表明:虽然两种方法测定总氮的结果精密度基本相同,但二者之间的系统误差存在显著差异,连续流动法较碱性过硫酸钾消解法的测定结果低5.4%。两种方法测定总氮结果的相对偏差与水体中藻细胞密度呈正相关性,当水体中藻细胞密度﹥2.41×108L-1时,对连续流动法测定总氮的结果产生显著影响,相对偏差超过标准规范要求。     

纳氏试剂比色法测定水体中氨氮影响因素的探讨

对纳氏试剂比色法测定水中氨氮的条件进行了优化,根据实际分析工作中的经验,对实验中出现的常见问题和解决办法进行了总结.     

氨氮测定过程中有关问题的探讨

针对纳氏比色法测定氨氮过程中存在的问题，提出了相应的解决办法。消除了混浊和泡沫干扰问题，降低了空白吸光度，提高了测定的准确度。     

冬小麦条锈病害与常规胁迫的定量化识别研究——高光谱应用

通过对人工田间诱发条锈病与常规的水胁迫及肥水协同胁迫的处理,分析获取的地物光谱数据及提取的归一化植被指数(NDVI)和光化学植被指数(PRI),定性地研究了条锈病害胁迫与常规胁迫条件下冬小麦冠层光谱特征的差异和规律,并进一步利用高光谱对冬小麦条锈病与常规胁迫进行了定量化的识别研究。选用NDVI和PRI建立二维空间坐标,形成病害胁迫、常规的水胁迫及肥水协同胁迫植被指数的空间分布散点图,结果表明NDVI值大于4.324×PRI 0.976的区域即为条锈病胁迫发生区域。经验证,上述定量化表达的分类识别精度达到了70%以上。     

吖啶黄褪色分光光度法测定环境水样中的亚硝酸盐氮

利用在酸性介质中,吖啶黄与亚硝酸根反应并在波长436啪处的吸光度与亚硝酸根浓度呈线性关系,提出并建立了测定亚硝酸盐氮的新方法。亚硝酸盐氮含量在0～300μg/L内符合比尔定律。本方法的检出限为0．004mg/L。实验室内相对标准偏差不超过2．7％,加标回收率在93％～112％之间。     

制药废水硝化-反硝化除氮研究

含高浓度氮的制药废水经好氧生化处理后,虽然出水的ＣＯＤ,ＢＯＤ５均可达到行业排放标准,但ＴＮ仍高达约１７０ｍｇ／Ｌ。本研究在曝气池中设置填料,利用生物膜外层好氧,内层缺氧厌氧的条件,使硝化－反硝化脱氮在同一构筑物内进行,ＮＨ３－Ｎ和ＴＮ去除率分别可达约９０％和７０％。在本试验条件范围内,温度越高,负荷越低,硝化和反硝化作用越完全,ＮＨ３－Ｎ和ＴＮ去除率越高。     

Long Term Trends in Sulphur and Nitrogen Deposition in Europe and the Cause of Non-linearities

Emissions of sulphur and oxidized nitrogen compounds in Europe have been reduced following a series of control measures during the last two decades. These changes have taken place during a period in which the primary gases and the wet deposition throughout Europe were extensively monitored. Since the end of the 1970s, for example land based sulphur emissions declined by between 90 and 70% depending on the region. Over the same period the total deposition of sulphur and its partitioning into wet and dry deposition have declined, but the spatial pattern in the reduction in deposition differs from that of emission and has changed with time. Such non-linearities in the emission-deposition relationship are important to understand as they complicate the process of assessing the effects of emission reduction strategies. Observed non-linearities in terrestrial sulphur emission-deposition patterns have been identified in north west Europe due to increases in marine emissions, and are currently slowing the recovery of freshwater ecosystems. Changes in the relative amounts of SO₂ and NH₃ in air over the last two decades have also changed the affinity of terrestrial surfaces for SO₂ and have therefore changed the deposition velocity of SO₂ over substantial areas. The consequence of this effect has been the very rapid reduction in ambient SO₂ concentration in some of the major source areas of Europe, where NH₃ did not change much. Interactions between the different pollutants, generating non-linearities are now being incorporated in long-range transport models to simulate the effects of historical emission trends and to provide projections into the future. This paper identifies non-linearities in emission deposition relationships for sulphur and nitrogen compounds in Europe using data from the EMEP long-rang transport model and measured concentration fields of the major ions in precipitation and of SO₂ and NO₂ in surface air.