鲢鱼放养控制北京城市河湖水华试验研究

介绍了利用鲢鱼控制北京城市河湖水华的试验研究,通过不同放养密度(0、17、51和103 g/m3)的现场围隔试验,对鲢鱼放养对水体水质和浮游生物的影响进行了分析.研究结果表明,鲢鱼放养使有鱼围隔中浮游生物量极低,从而使浮游植物基本不受浮游动物影响,而直接受鱼类影响;同时,中等密度(51 g/m3)的鲢鱼放养使水华蓝藻和微小藻的生长均得到了有效抑制,使藻类生物量最低.     

沈阳市苏家屯区危险废物管理、处置现状与对策

对沈阳市苏家屯区危险废物现状进行了调查,分析了危险废物的来源、产生量、特征及存在的主要问题。在此基础上,提出对危险废物管理处置对策,包括开展危险废物申报登记;加强苏家屯区危险废物监督管理;源头控制危险废物污染产生和建设危险废物集中处置场等。     

酸雨作用下中亚带森林冠层淋溶规律研究

2001年1月～2002年6月对韶山亚热带常绿阔叶林4个采样区进行了酸雨的监测,以监测数据为依据,分析研究了林内穿透水中主要离子的淋溶规律。结果表明:大气降水经过森林冠层后pH值明显升高,韶山亚热带常绿阔叶林对SO42-、NO3-、Mg2+、NH4+离子具有吸收作用,特别是NH4+和NO3-离子。SO42-、Ca2+和Mg2+离子的冠层淋溶百分率随降雨量的增加有明显减少的趋势。Ca2+、K+和Cl-随着pH的增加,其冠层淋溶百分率呈增加趋势。韶山地区在常年酸沉降作用下,森林冠层对酸性离子SO42-、NO3-的吸收作用最强。根据18个月离子浓度平均值来计算,韶山地区森林冠层离子的淋溶序列为:K+>Ca2+>Cl->Mg2+>SO42->NO3->NH4+>Na+。     

毒死蜱对于隆线溞和中华薄壳介混合种群的影响

研究了毒死蜱对隆线溞(Daphnia carinata)和中华薄壳介(Dolerocypris sinensis)混合种群的种群密度、N-乙酰-β-D-氨基葡萄糖苷酶(NAGase)比活力和隆线溞游离态几丁质酶免疫可反应蛋白(chitinase-IR)的影响。结果表明,在毒死蜱质量浓度高于0.05μg/L的条件下,毒死蜱对两种生物会有抑制作用,并且基本随暴露浓度的升高而增强。不过,随着水中残留的毒死蜱浓度降低,抑制作用会减弱。计算毒死蜱对隆线溞和中华薄壳介的最高无作用浓度(NOEC)和最低有效浓度(LOEC)发现,中华薄壳介对毒死蜱的敏感性高于隆线溞。在生态风险评估工作中,NOEC或LOEC使用时间加权平均浓度会使评价结果更加准确。     

Enhanced triallyl isocyanurate (TAIC) degradation through application of an O3/UV process: Performance optimization and degradation pathways

• UV/O₃ process had higher TAIC mineralization rate than O₃ process. • Four possible degradation pathways were proposed during TAIC degradation. • pH impacted oxidation processes with pH of 9 achieving maximum efficiency. • CO₃^2– negatively impacted TAIC degradation while HCO₃^– not. • Cl^– can be radicals scavenger only at high concentration (over 500 mg/L Cl^–). Triallyl isocyanurate (TAIC, C₁₂H₁₅N₃O₃) has featured in wastewater treatment as a refractory organic compound due to the significant production capability and negative environmental impact. TAIC degradation was enhanced when an ozone(O₃)/ultraviolet(UV) process was applied compared with the application of an independent O₃ process. Although 99% of TAIC could be degraded in 5 min during both processes, the O₃/UV process had a 70%mineralization rate that was much higher than that of the independent O₃ process (9%) in 30 min. Four possible degradation pathways were proposed based on the organic compounds of intermediate products identified during TAIC degradation through the application of independent O₃ and O₃/UV processes. pH impacted both the direct and indirect oxidation processes. Acidic and alkaline conditions preferred direct and indirect reactions respectively, with a pH of 9 achieving maximum Total Organic Carbon (TOC) removal. Both CO₃^2– and HCO₃^– decreased TOC removal, however only CO₃^2– negatively impacted TAIC degradation. Effects of Cl^– as a radical scavenger became more marked only at high concentrations (over 500 mg/L Cl^–). Particulate and suspended matter could hinder the transmission of ultraviolet light and reduce the production of HO· accordingly.     

Hyperspectral Characteristics of Canopy Components and Structure for Phenological Assessment of an Invasive Weed

Spectral reflectance values of four canopy components (stems, buds, opening flowers, and postflowers of yellow starthistle (Centaurea solstitialis)) were measured to describe their spectral characteristics. We then physically combined these canopy components to simulate the flowering stage indicated by accumulated flower ratios (AFR) 10%, 40%, 70%, and 90%, respectively. Spectral dissimilarity and spectral angles were calculated to quantitatively identify spectral differences among canopy components and characteristic patterns of these flowering stages. This study demonstrated the ability of hyperspectral data to characterize canopy components, and identify different flowering stages. Stems had a typical spectral profile of green vegetation, which produced a spectral dissimilarity with three reproduction organs (buds, opening flowers, and postflowers). Quantitative differences between simulated flower stages depended on spectral regions and phenological stages examined. Using full-range canopy spectra, the initial flowering stage could be separated from the early peak, peak, and late flowering stages by three spectral regions, i.e. the blue absorption (around 480 nm) and red absorption (around 650 nm) regions and NIR plateau from 730 nm to 950 nm. For airborne CASI data, only the red absorption region and NIR plateau could be used to identify the flowering stages in the field. This study also revealed that the peak flowering stage was more easily recognized than any of the other three stages.     

火力发电企业排污自行监测质量提升

针对目前火力发电企业排污自行监测过程中存在的质量管理体系不完善、手工监测能力不足、对外委监测机构监督环节薄弱等突出问题,从质量管理体系建设、质量控制机制建立、第三方检测机构选择及智能化手段应用四个方面提出火力发电企业排污自行监测质量提升改进建议,为自行监测数据结果的科学性、准确性提供可靠的质量保证。     

胶束强化超滤去除水中双酚A

采用截留分子量(MWCO)为5000 Dalton、1000 Dalton的聚砜超滤膜,MWCO为1 kDa的再生纤维素超滤膜;采用十二烷基苯磺酸钠(SDBS)、曲拉通100(TritonX-100)、吐温80(Tween-80)、烷基多苷(APG)为表面活性剂,用胶团强化超滤工艺去除水中双酚A。研究了不同材质和截留分子量的超滤膜、表面活性剂浓度、膜操作压力、溶液pH和溶液中电解质等因素对该工艺的影响。结果表明,SDBS对双酚A有较好的去除效果,去除率在80%以上。在H+和Na+存在的条件下,双酚A的截留率增加,透过液中SDBS浓度降低。SDBS与非离子表面活性剂的复配可以提高双酚A截留率,降低透过液中SDBS的浓度,复配效果优劣顺序为Tween-80TritonX-100APG。     

污泥静态好氧发酵中堆体板结与通风的研究

为研究污泥静态好氧发酵中板结对强制通风和发酵进程的影响,降低通风能耗,基于理论研究确定了压降为强制通风风量的决定性因素,并通过实验获取不同发酵阶段和强制通风条件下的堆体通风量和抗剪强度数据,分析堆体内板结的形成规律,通过计算验证板结的形成和消失对通风的影响,提出了需要改善通风的时间节点;然后基于风机的变频控制研究了风机功率变化对强制通风的影响。提出的通风解决方案采用阶段变频通风,实现了堆体温度和通风风量的有效控制。     

超高效气溶胶净化系统有效性现场检验研究

各类超高效气溶胶净化系统普遍存在的较为突出的问题是:缺乏系统工作有效性现场检测手段,难以判断系统防护是否失效。根据超高效滤料过滤特性和测试原理,并在分析了大气气溶胶对过滤效率测试影响的基础上,提出大气气溶胶背景下,基于粒数浓度测量和使用发生的高浓度单分散气溶胶作为实验气溶胶的净化系统防护有效性现场检验测试技术及系统组成,并进行了验证。