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141.
142.
对闸北区空气自动监测站2009年SO2、NO2、PM10的浓度和气象参数变化特征进行研究,可吸入颗粒物的时间变化特征表明,总体上呈现冬春季高、夏秋季低;PM10与降水量、相对湿度、温度呈现一定的负相关性,但与风速的相关性随季节不同而不同,与气压略呈正相关性。对典型日和灰霾日PM10、SO2、NO2以及相应气象因子的特征进行了分析比较。 相似文献
143.
培养创新型的环境工程专业培养人才是目前高等学校环境工程教育工作者面临的一个重要课题。近年来中国环境专业的招生规模在逐渐加大,面对着高等教育的日益大众化,环境工程领域的学生近年来面临的就业压力也在不断增大,大学的培养观念和能力面临着挑战。高等院校作为环境工程技术人才的培养基地,如何适应国家发展的需要,培养具有创新性能力的的环境工程专业人才是非常必要的。本文介绍了中国矿业大学(北京)近年来在进行矿业特色环境专业创新人才培养方面的做法,以期对现阶段环境工程专业的建设提供一定的借鉴意义。 相似文献
144.
电化学产电菌的分离及性能评价 总被引:2,自引:1,他引:1
利用兼性滚管法分离了折流板空气阴极微生物燃料电池(BAFMFC)A、B两格室的阳极生物膜,共获得19株纯菌.将菌株投加至无菌立方型反应器中,检验其产电特性.利用交流阻抗法测量各纯菌电池的内阻,结果显示38个电池的欧姆内阻为25Ω±5Ω,说明了各电池的产电差异来源于菌株本身的活性.其他运行条件均保持不变,在1000Ω外阻下,7株纯菌电池的输出电压在200mV以上.其中,A格室产电活性最高的菌株(A2)产生的最大电压为328mV,输出的最大功率密度为165.1mW/m2,B格室产电活性最高的菌株(B1)最大电压为241mV,最大功率密度为214.4mW/m2.原子力显微镜和脂肪酸快速鉴定表明,A2为肠杆菌科的杆菌,B1为厚壁菌门的芽孢杆菌. 相似文献
145.
印钞废水属高浓度难降解有机废水,对环境污染严重。鉴于现有处理工艺出水普遍不达标的情况,通过对比实验确定了改进方案:超滤浓缩液离心出水在进入接触氧化池前,增加新的处理单元(Fenton氧化-混凝)。Fenton氧化最佳条件:FeSO4.7H2O投加量14 g/L,H2O2的投加量34 mL/L,初始pH值6.0,氧化反应时间1.5h,温度18.8℃;混凝过程最佳条件:PAC投加量4 g/L,PAM(5‰)投加量10 mg/L,pH值7。新增单元对废水中COD去除率接近80%,可生化性提高1.6倍,色度降低36%。 相似文献
146.
Xinxin Wang Zhen Han Zhihui Bai Jingchun Tang Anzhou M Jizheng He Guoqiang Zhuang 《环境科学学报(英文版)》2011,23(11):1858-1864
The impact of petroleum on archaeal community in salinealkali soils was investigated, which will expand the knowledge of the archaeal population involved in the natural attenuation of hydrocarbons in extreme environments. 相似文献
147.
The activities of CeO2 nanocubes calcined at different temperatures were tested for catalytic oxidation of o-xylene. Using CeO2 nanocubes as catalysts, complete catalytic oxidation of o-xylene was achieved below 210℃. The CeO2 nanomaterials were characterized by means of BET, X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). From the TEM images, all Ce02 nanocubes displayed cubic morphology irrespective of calcination temperature. The HRTEM images revealed that these nanocubes were enclosed by reactive {001}planes, which may contribute to the intrinsically catalytic property of o-xylene oxidation. The higher activity of Ce02 nanocubes calcined at 550℃ than those calcined at above 550℃ was attributed to their smaller crystallite size and larger surface area. The influences of reaction conditions were also studied, which found that a higher reaction temperature was necessary for complete catalytic oxidation of o-xylene at higher weight hourly space velocity (WHSV) and o-xylene concentration. 相似文献
148.
规划环境影响评价是以可持续发展的思想为出发点,通过调整规划布局或规模从规划源头预防环境污染和生态破坏.文章探讨了化工建设规划的生态环境影响评价理论和方法学体系,并以武汉化工新城为例,对该理论方法体系进行探讨. 相似文献
149.
Comparison of quartz sand, anthracite, shale and biological ceramsite for adsorptive removal of phosphorus from aqueous solution 总被引:1,自引:0,他引:1
The choice of substrates with high phosphorus adsorption capacity is vital for sustainable phosphorus removal from waste water in constructed wetlands. In this study, four substrates were used: quartz sand, anthracite, shale and biological ceramsite. These substrate samples were characterized by X- ray diffractometry and scanning electron microscopy studies for their mineral components (chemical components) and surface characteristics. The dynamic experimental results revealed the following ranking order for total phosphorus (TP) removal efficiency: anthracite 〉 biological ceramsite 〉 shale 〉 quartz sand. The adsorptive removal capacities for TP using anthracite, biological ceramsite, shale and quartz sand were 85.87, 81.44, 59.65, and 55.98 mg/kg, respectively. Phosphorus desorption was also studied to analyze the substrates' adsorption efficiency in wastewater treatment as well as the substrates' ability to be reused for treatment. It was noted that the removal performance for the different forms of phosphorus was dependent on the nature of the substrate and the adsorption mechanism. A comparative analysis showed that the removal of particulate phosphorus was much easier using shale. Whereas anthracite had the highest soluble reactive phosphorus (SRP) adsorptive capacity, biological ceramsite had the highest dissolved organic phosphorus (DOP) removal capacity. Phosphorus removal by shale and biological ceramsite was mainly through chemical adsorption, precipitation or biological adsorption. On the other hand, phosphorus removal through physical adsorption (electrostatic attraction or ion exchange) was dominant in anthracite and quartz sand. 相似文献
150.
Catalytic oxidation is widely used in pollution control technology to remove volatile organic compounds. In this study, Pd/ZSM-5 catalysts with different Pd contents and acidic sites were prepared via the impregnation method. All the catalysts were characterized by means of N2 adsorption- desorption, X-ray fluorescence (XRF), HE temperature programmed reduction (H2-TPR), and NH3 temperature programmed desorption (NH3-TPD). Their catalytic performance was investigated in the oxidation of butyl acetate experiments. The by-products of the reaction were collected in thermal desorption tubes and identified by gas chromatography/mass spectrometry. It was found that the increase of Pd content slightly changed the catalytic activity of butyl acetate oxidation according to the yield of CO2 achieved at 90%, but decreased the cracking by-products, whereas the enhancement of strong acidity over Pd-based catalysts enriched the by-product species. The butyl acetate oxidation process involves a series of reaction steps including protolysis, dehydrogenation, dehydration, cracking, and isomerization. Generally, butyl acetate was cracked to acetic acid and 2- methylpropene and the latter was an intermediate of the other by-products, and the oxidation routes of typical by-products were proposed. Trace amounts of 3-methylpentane, hexane, 2-methylpentane, pentane, and 2-methylbutane originated from iso4merization and protolysis reactions. 相似文献