A comparison study of the start-up of a MnOx filter for catalytic oxidative removal of ammonium from groundwater and surface water

As an efficient method for ammonium (NH4+) removal, contact catalytic oxidation technology has drawn much attention recently, due to its good low temperature resistance and short start-up period. Two identical filters were employed to compare the process for ammonium removal during the start-up period for ammonium removal in groundwater (Filter-N) and surface water (Filter-S) treatment. Two types of source water (groundwater and surface water) were used as the feed waters for the filtration trials. Although the same initiating method was used, Filter-N exhibited much better ammonium removal performance than Filter-S. The differences in catalytic activity among these two filters were probed using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and compositional analysis. XRD results indicated that different manganese oxide species were formed in Filter-N and Filter-S. Furthermore, the Mn3p XPS spectra taken on the surface of the filter films revealed that the average manganese valence of the inactive manganese oxide film collected from Filter-S (FS-MnOx) was higher than in the film collected from Filter-N (FN-MnOx). Mn(IV) was identified as the predominant oxidation state in FS-MnOx and Mn(III) was identified as the predominant oxidation state in FN-MnOx. The results of compositional analyses suggested that polyaluminum ferric chloride (PAFC) used during the surface water treatment was an important factor in the mineralogy and reactivity of MnOx. This study provides the theoretical basis for promoting the wide application of the technology and has great practical significance.     

煤矿轴流式局部通风机的降噪

煤矿局部通风机（简称局扇）的噪声是煤矿掘进中的主要噪声源。分析了局扇噪声产生的机理。综述了从局扇的噪声源和传播途径上控制噪声的方法，为局扇的降噪提供了有益的参考。     

环境影响评价中公众参与有效性的研究

对中国环境影响评价中公众参与的现状和存在的问题进行了调研分析,筛选出影响公众参与有效性的指标,并采用层次分析法建立了公众参与有效性的评价指标体系。选取上海市近几年完成的50余本环境影响报告书作为抽样样本,对上海市环评报告中公众参与的有效性进行了评估,最后结合存在的问题提出了提高有效性的对策措施。     

氨法烟气脱硫技术的工艺研究

采用亚硫酸铵作为吸收剂,对模拟烟气进行氨法烟气脱硫实验。考察了进口烟气温度、吸收液pH值、吸收液浓度、液气比对脱硫效率的影响,并对亚硫酸铵的氧化问题进行了研究。实验结果表明：进口烟气温度与脱硫效率成反比关系;吸收液pH值、吸收液浓度与脱硫效率成正比关系;吸收液pH值大于6.3、浓度大于1%时,氨逃逸随着二者的增大而增多...     

Toxicity of copper, lead, and cadmium on the motility of two marine microalgae Isochrysis galbana and Tetraselmis chui

Computer assisted movement tracking was used to characterize the motility of two marine microalgae, Isochrysis galbana and Tetraselmis chui, and to investigate the toxicity of Cu, Pb, and Cd on motile percentage, curvilinear velocity, average path velocity, straight line velocity, linearity, straightness, and wobble. Except for motile percentage, all other motility parameters di ered significantly between I. galbana and T. chui. Based on relative motile percentage data, the median e ective concentration (EC50) of Cu on the motility of I. galbana and T. chui was 31.4 and 1.3 mol/L, respectively, while for Pb it was 37.8 and 10.9 mol/L and for Cd it was 121.6 and 37.8 mol/L, respectively. Compared to I. galbana, T. chui was more sensitive to all tested metals. The toxic e ect of the heavy metals on motility exhibited the following decreasing order for both species: Cu > Pb > Cd. Our results indicate that I. galbana and T. chui motility is sensitive to heavy metals and can be used as an indicator for toxicology bioassays.     

Involvements of chloride ion in decolorization of Acid Orange 7 by activated peroxydisulfate or peroxymonosulfate oxidation

The effects of Cl^- on the decolorization of AO7 by SO₄^·- based-peroxydisulfate or peroxymonosulfate oxidation under various activated conditions were different.     

烟尘测试过程中的质量控制

锅炉烟尘测试是一项技术要求高,环节多的复杂工作,本文根据资料和几年来监测的实践经验,对烟尘测试中影响测定结果的诸多因素进行探讨,并提出质量控制措施。     

聚合物驱油工程交联剂职业健康风险分析

运用风险积分计算板评价聚合物驱油工程交联剂健康风险,为职业安全健康管理工作者和评价人员介绍一种新的评价方法。     

含油废水对鲤鱼肝脏微粒体芳烃羟化酶的活性诱导研究

以鲤鱼肝脏微粒体为实验体系,运用体外实验方法,研究三种含油废水对芳烃羟化酶的活性影响,结果表明,三种含油废水对芳烃羟化酶活性都表现出不同程度的诱导,随着含油量的增大,AHH活性升高,并有相似的变化趋势。芳烃羟化酶活性升高可以作为监测含油废水对水体污染的一种生物指标。     

FCC汽油吸附脱硫技术

与常规的加氢脱硫技术相比,吸附脱硫技术具有易于操作,故障率低,超低的硫含量,低辛烷值损耗,低操作成本,几乎不消耗氢气等优点,是解决当代能源、资源和环境问题的重要技术。本文将就吸附脱硫技术的研究现状做简要评述。