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311.
研究了利用电子束辐照降解氰化钠水溶液的效果.分别考察了CN-初始浓度、溶解氧浓度、辐照剂量率对 CN-降解效果的影响.采用总有机碳(TOC)分析仪、离子色谱仪(IC)、紫外分光光度计等分析了 CN-在不同实验条件下的辐照降解产物.实验结果表明,电子束能有效降解水溶液中的 CN-,较低的 CN-初始浓度,较高的辐照剂量,较高的溶解氧浓度以及较低的辐照剂量率能够提高CN-降解效率.CN-辐照后转化为 NH3、NO3-、NO2-、碳酸盐和有机物.  相似文献   
312.
The photocatalytic degradation of dye pollutant sulforhodamine-B (SRB) in aqueous titanium dioxide (TiO2) dispersions was examined under three lighting regimes: UV light (330 nm〈λ〈 380 nm), sunlight, and visible light (λ〉450 nm), all investigated at pH=2.5. Total organic carbon (TOC) and chemical oxygen demand (CODer) assays show that the degradation rate of SRB is much higher when irradiated with UV and sunlight compared with visible light. The temporal concentration changes of SRB illustrated a first-order reaction and the rate constant, k, is 0.197 min^-1, 0.152 min^-1, 0.027 min^-1, respectively, under the three lighting conditions. The final mineralized products were amine compounds identified by infrared spectrophotometry. When irradiated with visible light, the photocatalytic degradation rate could be improved by lowering the H2O2 concentration and inhibited by increasing the H2O2 concentration, but results contrary to the above were obtained when UV light was used for irradiation.  相似文献   
313.
电子束烟气治理技术的应用   总被引:2,自引:0,他引:2  
简述了电子束烟气治理技术研究结果基础上的工业规模装置的工艺流程,介绍了10万kW级发电机组烟气治理示范装置的主要设计参数及其可行性方案概述。  相似文献   
314.
地下水中轻质有机污染物(LNAPL)透镜体研究   总被引:10,自引:0,他引:10  
在二维砂槽模型中模拟了轻质油在均匀多孔介质地下水非饱和区中的运移过程。模拟结果表明,地下水毛细区是轻质油污染的重点区,除了LNAPL的残留以外,进入地下水饱和的LNAPL终将被地下水顶托回到毛细区中,毛细区以上的约大多民将在重力作用下进入毛细区中,试验中观察到达稳定状态时LNAPL透镜体的上边缘略微高出毛细区。利用多孔介质毛细管模型,建立了利用界面张力、接触角、介质特征孔隙直径等物理量估算不同位置  相似文献   
315.
An extensive visibility monitoring was carried out simultaneously in the urban area of Gwangju and the rural area of Anmyon, Korea. This study examines patterns of visibility impairment and haze-forming pollutant concentrations on both sites resulting from natural and anthropogenic sources of gases and particles. Optical visibility measurements by a transmissometer, a nephelometer and an aethalometer provide aerosol light extinction, scattering, and absorption coefficients for both sites. In order to investigate the physico-chemical characteristics of atmospheric aerosols, aerosol samples were collected by various aerosol samplers at GJVMS (Gwangju Visibility Monitoring Station) and at KGAWO (Korea Global Atmosphere Watch Observatory), respectively. In addition, haze characteristics causing visibility impairment at those two sites were analyzed to obtain source contributions by regionally transported aerosols using grid analysis and display system (GrADS) from NECP reanalysis data. During the intensive monitoring period, ammonium sulfate was dominantly responsible for the fine particle mass loading at GJVMS, whereas organic carbon was the largest contributor at KGAWO. Light scattering by particles accounted for 52.8 to 81.3% of the range at the urban site, GJVMS and for 72.1 to 94.2% of the range at the rural site, KGAWO. Light absorption by the EC and NO2 was between 14.5 and 34.8% at GJVMS, which was higher than the observed 1.1 ∼ 6.8% at KGAWO, respectively. Light scattering by aerosol was higher in the rural area than in the urban area. And organic carbon concentration was observed to be significantly higher than the concentration of elemental carbon at KGAWO. These haze-forming carbonaceous particles originate from anthropogenic pollutants at the urban atmosphere but they can be produced by natural environments such as marine and forest at the rural atmosphere.  相似文献   
316.
A distinctive kind of organic carbon aerosol that could absorb ultraviolet-visible radiation is called brown carbon (BrC), which has an important positive influence on radiative budget and climate change. In this work, we reported the absorption properties and potential source of BrC based on a seven-wavelength aethalometer in the winter of 2018–2019 at an urban site of Sanmenxia in Fenwei Plain in central China. Specifically, the mean value of BrC absorption coefficient was 59.6 ± 36.0 Mm?1 at 370 nm and contributed 37.7% to total absorption, which made a significant impact on visibility and regional environment. Absorption coefficients of BrC showed double-peak pattern, and BrC had shown small fluctuations under haze days compared with clean days. As for the sources of BrC, BrC absorption coefficients expressed strong correlations with element carbon aerosols and primary organic carbon aerosols, indicating that most of BrC originated from primary emissions. The linear correlations between trace metal elements (K, As, Fe, Mn, Zn, and Pb) and BrC absorption coefficients further referred that the major sources of BrC were primary emissions, like coal burning, biomass burning, and vehicle emissions. The moderate relationship between BrC absorption coefficients and secondary organic aerosols suggested that secondary production of BrC also played an important role. The 120 hr backward air mass trajectories analysis and concentration-weighted trajectories analysis were also used to investigate potential sources of BrC in and around this area, which inferred most parts of BrC were derived from local emissions.  相似文献   
317.
以城市污水处理厂脱水污泥为供试材料,通过比较电子束辐照、热水解及组合工艺对污泥破解率的影响发现:随着热水解温度从90 ℃提高到120、140和160 ℃,污泥破解率分别从14.82%升高至19.97%、23.16%和33.28%。当热水解温度低于140 ℃时,氨氮/溶解性总氮的比值(NH3-N/TSN)在0.14~0.17之间波动,而温度达160 ℃时,NH3-N/TSN升高至0.22。另一方面,当污泥吸收剂量由5 kGy增加至10、15、20 kGy时,污泥破解率分别由3.77%缓慢上升到4.87%、5.01%、5.42%。但是,NH3-N/TSN维持在0.32~0.33之间,比热水解处理约提高1倍。在组合工艺中,15 kGy+90 ℃热水解30 min污泥破解率最高,达25.1%,NH3-N/TSN≈0.22。实验证明:热水解对污泥破解效果显著,但电子束辐照可进一步将大分子有机物质降解为小分子物质。  相似文献   
318.
针对均值污染指数评价方法在微污染水体环境质量评价上存在的缺陷,提出新的改进方法即活性污染指数法进行评价.根据吉林省白城市月亮湖水库2001~2005年监测结果,同时利用这两种方法进行评价,结果显示活性污染指数法评价白城市水库水质更客观和真实有效.  相似文献   
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