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471.
树脂吸附-Fenton 试剂氧化法预处理炼油碱渣废水   总被引:1,自引:0,他引:1  
采用树脂吸附-Fenton 试剂氧化组合工艺对某炼油企业炼油碱渣废水进行预处理.实验确定的最佳工艺条件为:3 种树脂串联吸附,废水流量0.33 mL/ min,H2O2加入量0.20 mol / L,n(H2O2)1 n(Fe2 +)= 12,Fenton 试剂氧化进水pH 3,Fenton 试剂氧化反应时间120 m...  相似文献   
472.
催化光度法测定水中痕量亚硝酸根   总被引:5,自引:0,他引:5  
基于亚硝酸根对溴酸钾氧化结果紫而使其褪色的催化作用,建立了灵敏的催化光度测定痕量亚硝酸根的新方法,测定范围为0.02-0.16μg/mL,用于水样中亚硝酸根的测定,获得了满意结果。  相似文献   
473.
● NH3 in biogas had a slight inhibitory effect on dry reforming. ● Coexistence of H2S and NH3 led to faster decline of biogas conversion. ● Regeneration was effective for catalysts deactivated under synergetic effect. Biogas is a renewable biomass energy source mainly composed of CH4 and CO2. Dry reforming is a promising technology for the high-value utilization of biogas. Some impurity gases in biogas can not be completely removed after pretreatment, which may affect the performance of dry reforming. In this study, the influence of typical impurities H2S and NH3 on dry reforming was studied using Ni/MgO catalyst. The results showed that low concentration of H2S in biogas could cause serious deactivation of catalyst. Characterization results including EDS, XPS and TOF-SIMS confirmed the adsorption of sulfur on the catalyst surface, which was the cause of catalyst poisoning. We used air calcination method to regenerate the sulfur-poisoned catalysts and found that the regeneration temperature higher than 500 °C could help catalyst recover the original activity. NH3 in the concentration range of 50–10000 ppm showed a slight inhibitory effect on biogas dry reforming. The decline rate of biogas conversion efficiency increased with the increase of NH3 concentration. This was related to the reduction of oxygen activity on catalyst surface caused by NH3. The synergetic effect of H2S and NH3 in biogas was investigated. The results showed that biogas conversion decreased faster under the coexistence of H2S and NH3 than under the effect of H2S alone, so as the surface oxygen activity of catalyst. Air calcination regeneration could also recover the activity of the deactivated catalyst under the synergetic effect of H2S and NH3.  相似文献   
474.
在1.5-50.0mg/L的浓度范围内,单甲脒农药对模型池塘生态系统中的浮游植物群落结构有明显影响。尤其在加药的头4d内,藻类种类、数量、多样性指数、种类数比及增长率明显下降,优势比显著上升,敏感种及清洁种减少甚至消失,高浓度(50.0mg/L)的单甲脒在2d内可把藻类全部杀灭。随试验时间的延长,药物不断降解,6d后藻类种类、数量、多样性指数又不断回升。随加药次数的增多,药物对藻类抑制作用明显减弱,藻类的种类、数量、多样性指数等指标不断上升,尤其是藻类数量增加明显,试验后期,藻类数量高低主要受N、P浓度大小的影响。  相似文献   
475.
新疆和田河绿色走廊演变机制及生态环境保护初析   总被引:1,自引:0,他引:1  
和田河绿色走廊是塔里木盆地中南北穿越塔克拉玛干沙漠的三条绿色走廊之一,具有重要的政治经济、生态、交通意义。绿色走廊的演变受到构造运动、气候波动和人为干扰等因素的影响。其中,人为干扰是绿色走廊现代生态环境演变过程中最重要最活跃的控制因素。建议加强流域水资源总体规划与统筹管理,兼顾生产、生活和生态用水,逐步改变农村居民燃料能源结构,从而保护绿色走廊生态健康。  相似文献   
476.
随着我国油田相继进入开发后期,传统的滤料及设备过滤精度已不能满足注水的要求。因此,研究并开发了具有一定抗油污能力的新型过滤材料,设计了新型的超精细过滤器系列产品。对滤料进行的室内实验结果表明,在开始过滤的近10h内,过滤后的水中含油量基本上满足注水的水质要求。在开始过滤的近20h内,滤层的水头损失随时间的变化较为平缓;随着过滤时间的延长,水头损失变化加剧。从现场实验可以看出,所设计的过滤器有良好的过滤性能和抗冲击能力。新型过滤材料的研究成功解决了油田含油污水精细过滤的问题,新型过滤器也是含油污水超精细过滤的理想产品。  相似文献   
477.
针对注水残渣含碱量大,盐、油及其它杂质含量高,处理困难等特点,研究出注水残渣固化修路工艺技术。注水残渣固化后,既消除了污染源,保护了周围环境的土壤及地下水资源,又减少了土地占用面积,从而取得了显著的经济效益。  相似文献   
478.
The organic-inorganic hybrid halide compounds have emerged as one of the most promising photoelectric material for their superior optoelectronic properties and hold great prospects for renewable energy substitutes and environmental protection as photocatalysis. Here, we report the optical properties of the Sb-based organic-inorganic hybrid ferroelectric materials: pyridine-4-aminium tetrachloroantimonate ((C5H7N2)SbCl4, sample 1), piperidin-1-aminium tetrachloroantimonate ((C5H13N2)SbCl4, sample 2) and tris(trimethylammonium) nonachlorodiantimonate (((CH3)3NH)3Sb2Cl9, sample 3), which are a kind of exploited efficient photocatalysts. Samples 2 and 3 exhibit distinct photoelectric respond, which are mainly ascribed to their minor narrow band-gap compared with sample 1. For the ferroelectrics, the intrinsic of spontaneous polarization of sample 3 at room temperature is favourable for the separation of photogenerated electrons and holes within the photorespond process. Moreover, sample 3 shows the highest efficiency of photo-decomposed Rhodamine B (90.2% within 80 min) and Methyl Orange (MO) (97.4% within 50 min), thanks to the photo-excited electrons and holes promoting the formation of oxidative radical species during the photo-redox progress. These findings prove that the development of a novel Sb-based organic-inorganic hybrid halide compounds with good stability in the degradation of organic dyes paves a way to designing new photocatalyst.  相似文献   
479.
Aerobic granule is a special microbial aggregate associated with biofilm structure. The formation of aerobic granular sludge is primarily depending on its bacterial community and relevant microbiological properties. In this experiment, a strain with high microbial attachment was isolated from aerobic granular sludge, and the detailed characteristics were examined. Its high attachment ability could reach 2.34 (OD600nm), while other low attachment values were only around 0.06-0.32, which indicated a big variation among the different bacteria. The strain exhibited a very special morphology with many fibric fingers under SEM observation. A distinctive behaviour was to form a spherical particle by themselves, which would be very beneficial for the formation and development of granular sludge. The EPS measurement showed that its PN content was higher than low attachment bacteria, and 3D-EEM confirmed that there were some different components. Based on the 16S rRNA analysis, it was identified to mostly belong to Stenotrophomonas. Its augmentation to particle sludge cultivation demonstrated that the strain could significantly promote the formation of aerobic granule. Conclusively, it was strongly suggested that it might be used as a good and potential model strain or chassis organism for the aerobic granular sludge formation and development.  相似文献   
480.
流动系统内生物膜的形成及控制   总被引:3,自引:0,他引:3  
应用辐射流动室(Radical Flow Chamber,RFC)技术宣地研究水力剪切力对硝化细菌在聚苯乙烯(PS)载体表面固定的。发现水力剪切力直接影响硝化细菌的固定。当作用于PS表面的水力剪切力大于8.0N/m^2时,硝化细菌基本不能在PS表面险境着;水力剪切力小于8.0N/m^2时,硝化细菌的固定程度随剪切力的减小而加强,直至达到最大,实验表明辐射液动室技术为定量研究生物膜形成及控制与水力剪  相似文献   
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