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991.
采用Cu-Ag/Al2O3复合催化剂在低温下选择性催化氧化 NH3.实验结果表明,Ag/Al2O3 和 Cu/Al2O3分别具有高氧化活性和高 N2选择性的优点;一定负载量范围内,Cu-Ag/Al2O3复合催化剂既具有高氧化活性(介于Ag/Al2O3和Cu/Al2O3之间),又具有Cu/Al2O3的高N2选择性,当反应温度为280℃时,Cu5%-Ag5%/Al2O3对NH3的氧化率大于96%,N2选择性大于95%.催化剂表面上形成的Ag2O 颗粒及其大小是影响催化剂选择性的一个重要因素. 相似文献
992.
微电解-生化工艺在硝基苯废水处理中的协同作用 总被引:14,自引:0,他引:14
采用微电解与生化工艺结合处理硝基苯废水。通过微电解提高废水的可生化性 ,使废水的BOD5 CODCr由 0 11提高至 0 2 6 ;利用H O工艺进行后续处理 ,在H柱水力停留时间为 2 0h ,O柱水力停留时间为 10h的条件下 ,废水的总CODCr去除率为 86 % ,硝基苯的去除率为 99% 相似文献
993.
絮凝沉淀-H2O2/UV体系处理发制品废水的研究 总被引:1,自引:0,他引:1
研究了发制品废水经絮凝沉淀-H2O2/UV体系处理的可行性。结果表明,废水经处理后,COD去除率可达90%以上,色度去除率达100%,探讨了投药量、反应pH、反应时间等因素对COD去除率的影响,并比较了H2O2/F^2 、H2O2/UV、H2O2/Fe^2 /UV三种体系的处理效果。 相似文献
994.
利用磁场协同Ca2O2/Fe2 催化氧化体系处理活性红染料废水,研究不同磁化时间、磁场强度和催化氧化各种影响因素下对活性红染料模拟废水的去除率.结果表明:在pH值为3,C(FeSO4·7H2O)=50 mg,C(Ca2O2)=1.45g条件下,反应20min,去除率达62.5%.外加磁场磁场强度为427.8 mT的作用下,磁化反应20 min,CODCr的去除率提高了8.3%. 相似文献
995.
IntroductionColorsubstancesindyeingeffluentsnormallycausecertaindifficultiesintraditionalbiologicaltreatmentprocessesduetothedyemoleculesarehighlystructuredpolymersandtheirtoxicity (Hamza ,1980 ;Ginocchinio ,1984 ;MaKay ,1980 ) .Itisnecessarytoimprovethetreatmente… 相似文献
996.
N2 O在对流层中是长寿命的痕量温室气体 ;在平流层 ,它是破坏O3层主要痕量气体之一NO的生成源。本文主要综述了N2 O的大气浓度演变、大气寿命、对温室效应的贡献、大气化学等 ,着重探讨了可能存在的N2 O大气生成和消耗过程 相似文献
997.
NOx emission abatement catalysts V2O5 supported on variousTiO2 including anatase, rutile and mixture of both have beeninvestigated with various physico-chemical measurements such asBET, NH3-TPD, NARP, XRD and so on, and the effect of TiO2 surfaceproperties on the SCR activity of V2O5/TiO2 catalysts was studied.It has been found that the TiO2 surface properties had strongaffect on the SCR activity of V2O5/TiO2 catalysts. The strongeracidic property resulted the higher exposure of active sites aswell as the higher SCR activity. 相似文献
998.
LIU Jian-dong ZHOU Xiu-ji CHEN De-liang OUYANG Zhi-yun WANG Xiao-ke Achberger Christine 《环境科学学报(英文版)》2005,17(4):686-690
A biogeochemical model(DNDC) is combined with a plant ecological model to estimate N2O emission from rice paddy fields in the Yangtze River Delta region. The model is driven by local meteorological, soil, and physiological data and is validated for 1999 and 2000 at a site in the region, which showed that the simulated N2O emissions agree fairly well with the observed data. This adds some confidence in the estimated N2O emissions during 1950 and 2000 in the Hangzhou Region. A significant correlation between the N2O emissions and the population for the Hangzhou Region is found, which is due to a combination of increased application of fertilizers and cultivated area.Such a correlation can not be established for the whole Yangtze River Delta region when the data of both urban and rural are as areincluded. However, when the data from the heavily urbanized areas are excluded, a significant correlation between population and N2O emissions emerges. The results show clearly that both the temporal and the spatial N2O emissions have significant positive relationship with population under traditional farming practice. These results have implications for suitable mitigation options towards a sustainable agriculture and environment in this region. 相似文献
999.
Saima Noor Shamaila Sajja Sajjad Ahmed Khan Leghari Cristina Flox Saeed Ahmad 《环境科学学报(英文版)》2021,33(10):107-119
The promising solar irradiated photocatalyst by pairing of bismuth oxide quantum dots (BQDs) doped TiO2 with nitrogen doped graphene oxide (NGO) nanocomposite (NGO/BQDs-TiO2) was fabricated. It was used for degradation of organic pollutants like 2,4-dichlorophenol (2,4-DCP) and stable dyes, i.e. Rhodamine B and Congo Red. X-ray diffraction (XRD) profile of NGO showed reduction in oxygenic functional groups and restoring of graphitic crystal structure. The characteristic diffraction peaks of TiO2 and its composites showed crystalline anatase TiO2. Morphological images represent spherical shaped TiO2 evenly covered with BQDs spread on NGO sheet. The surface linkages of , , and vibrational modes are observed by Fourier transform infrared spectroscopy (FTIR) and Raman studies. BQDs and NGO modified TiO2 results into red shifting in visible region as studied in diffused reflectance spectroscopy (DRS). NGO and BQDs in TiO2 are linked with defect centers which reduced the recombination of free charge carriers by quenching of photoluminescence (PL) intensities. X-ray photoelectron spectroscopy (XPS) shows that no peak related to in NGO/BQDs-TiO2 is observed. This indicated that doping of nitrogen into GO has reduced some oxygen functional groups. Nitrogen functionalities in NGO and photosensitizing effect of BQDs in ternary composite have improved photocatalytic activity against organic pollutants. Intermediate byproducts during photo degradation process of 2,4-DCP were studied through high performance liquid chromatography (HPLC). Study of radical scavengers indicated that has significant role for degradation of 2,4-DCP. Our investigations propose that fabricated nanohybrid architecture has potential for degradation of environmental pollutions. 相似文献
1000.
如何提高处理效果和减少投资,是处理医疗废水的重点.A/O强化二段生物接触氧化 二氧化氯接触消毒工艺综合了厌(兼)氧、好氧以及A-B法的优点,克服了各自的缺点,通过对河南省商丘市第一人民医院的医疗废水处理,证明该工艺是一种处理医疗废水的行之有效的工艺. 相似文献