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991.
采用两级曝气生物滤池和多介质滤池相串联的中试装置,连续处理某炼油厂污水车间二浮出水,主要考察了中试装置对污水中主要污染物的去除效果和规律,并确定了适宜的气水比。试验结果表明:采用该工艺时,除石油类外,其它各项指标都达到《循环冷却水用再生水水质标准》(HG/T3923-2007)要求的水质指标;两级曝气生物滤池的气水比分别选用5.6∶1和5∶1为宜;验证了BAF是通过生物氧化和过滤两种作用来去除COD,第一段BAF以去除污水中碳化有机物为主,第二段BAF主要以去除污水中的NH4+-N为主。  相似文献   
992.
The circular economy (CE) concept was introduced in China to address environmental degradation and resource scarcity associated with rapid economic development. Chosen as a demonstration city, Dalian has implemented the CE strategy as a means of conserving water, materials, energy and land. This paper outlines some of the regional CE initiatives that have been successful to date in Dalian, including those focusing on conserving energy and water resources and others focusing on reduced industrial emissions. The paper details the approach used in implementing the CE concept in Dalian, tracing the foci and goals of the program, and the sectoral approach used to implement a CE. Although Dalian municipality has achieved many successes in implementing a CE, our paper identifies several challenges that, until recently, have held back complete implementation. These include: the lack of incentives for older industries to 'green' their operations, the lack of financial support to expand the CE concept, and a broad-based need for heightened public awareness and participation in CE initiatives. Our paper then identifies several responses by Dalian municipality to overcome these challenges, including pricing and tax reforms that serve as conservation incentives, the provision of financial support for CE promotion through budget reorganization, and the organization of CE training programs. Our paper concludes that, although CE initiatives have been successful in Dalian, more is possible and more is needed before Dalian can be designated a true 'eco-city'. The approach used by Dalian can provide guidance for other Chinese cities, although it is recognized that each city must tailor its own approach for differing contexts and conditions.  相似文献   
993.
我国垃圾焚烧发电CDM项目开发难点与实践分析   总被引:1,自引:0,他引:1  
基于我国目前垃圾焚烧发电CDM项目的开发现状,从不同的角度比较和分析了该类项目的特点,总结了其项目公示阶段出现的问题并对方法学修正内容进行了说明。同时,以实际项目为例,着重探讨了额外性论证中的投资比较分析、普及性分析等难点问题,最终得出结论并提出建议。  相似文献   
994.
N-(2-Hydroxyethyl)formamide (HF) was synthesized efficiently and used as a new additive to prepare thermoplastic starch/montmorillonite nanocomposite (TPS/MMT). Here, HF acted as both plasticizer for TPS and swelling agent for MMT. The hydrogen bond interaction among HF, starch and MMT was proven by Fourier-transform infrared (FT-IR) spectroscopy. By scanning electron microscope (SEM), starch granules were completely disrupted. Atomic force microscopy demonstrated that partially exfoliated TPS/MMT nanocomposite was formed. The crystallinity of corn starch, MMT, HF-plasticized TPS (HTPS) and TPS/MMT nanocomposite was characterized by X-ray diffraction (XRD). Thermal stability of HTPS and TPS/MMT was determined by thermogravimetric analysis (TGA). The water resistance of TPS/MMT nanocomposite increased compared with that of pure HTPS. Tensile strengths of TPS/MMT nanocomposites were higher than those of HTPS, but just the reverse for elongations at break.  相似文献   
995.
采用锰铜压阻法对Jo-9c在小尺寸装药条件下的爆压进行实验测定,得出不同装药条件下的爆压值,并对数据进行分析,得到约束条件和装药直径对爆压的影响规律.  相似文献   
996.
地震等自然灾害可以直接破坏主体结构.主要构件的加固、修复成为令人关心的研究课题.研究了方柱在不同预压力下的混凝土应力一应变关系,测得了混凝土、CFRP约束混凝土和CFRP约束预压混凝土棱柱体在轴压作用下的应力、应变数值,进行了混凝土棱柱体在预压后用CFRP加固的再受荷强度影响分析,为实际工程的加固设计提供了试验依据.  相似文献   
997.
以某电厂桩基础为工程依托,进行了两试桩竖向静载荷试验,探讨了砂泥岩地基大直径灌注桩的荷载传递机理和竖向承载特性。试验结果表明,砂泥岩地基大直径灌注桩在极限荷载作用达到稳定的情况下,荷载由桩侧阻力与桩端阻力共同承担,但表现出很强的摩擦桩特征,桩侧阻力的发挥取决于桩土相对位移,对于不同的土层,桩侧摩阻力达到极限时所对应的桩土之间相对位移不尽相同。针对试验结果,根据上部结构对基础沉降的要求,以桩顶沉降量来控制桩的竖向承载力,并提出了简化的计算公式,该公式考虑了桩土相对位移对桩侧阻力发挥的影响。  相似文献   
998.
一种新型光催化剂用于降解腈纶废水研究   总被引:5,自引:2,他引:3  
将1,10菲啰啉和铁Fe2+溶液配成络合物负载到D113树脂上作为可见光催化剂,利用该催化剂对腈纶废水进行了降解研究,考察了该负载型铁氮配合物催化剂处理腈纶废水的影响因素。由实验结果可知,该催化剂处理腈纶废水最佳条件为:过氧化氢浓度为400 mg/L,催化剂用量为5 g/L,最佳pH值范围为4~9,COD降解率可达68.7%,实现了在温和的反应条件下,即常温、常压、宽pH范围进行反应,充分利用了可见光来处理难降解有机物。  相似文献   
999.
Determination of the chemical compositions of atmospheric single particles in the Yellow Sea region is critical for evaluating the environmental impact caused by air pollutants emitted from mainland China and the Korean peninsula. After ambient aerosol particles were collected by the Dekati PM10 cascade impactor on July 17–23, 2007 at Tokchok Island (approximately 50 km west of the Korean coast nearby Seoul), Korea, overall 2000 particles (on stage 2 and 3 with cut-off diameters of 2.5–10 μm and 1.0–2.5 μm, respectively) in 10 samples were determined by using low-Z particle electron probe X-ray microanalysis. X-ray spectral and secondary electron image (SEI) data showed that soil-derived and sea-salt particles which had reacted or were mixed with SO2 and NOx (or their acidic products) outnumbered the primary and “genuine” ones (59.2% vs. 19.2% in the stage 2 fraction and 41.3% vs. 9.9% in the stage 3 fraction). Moreover, particles containing nitrate in the secondary soil-derived species greatly outnumbered those containing sulfate. Organic particles, mainly consisting of marine biogenic species, were more abundant in the stage 2 fraction than in the stage 3 fraction (11.6% vs. 5.1%). Their relative abundance was greater than the sum of carbon-rich, K-containing, Fe-containing, and fly ash particles, which exhibited low frequencies in all the samples. In addition, many droplets rich in C, N, O, and S were observed. They tended to be small, exhibiting a dark round shape on SEI, and generally included 8–20 at.% C, 0–12 at.% N, 60–80 at.% O, and 4–10 at.% S (sometimes with <3 at.% Mg and Na). They were attributed to be a mixture of carbonaceous matter, H2SO4, and NH4HSO4/(NH4)2SO4, mostly from the reaction of atmospheric SO2 with NH3 under high relative humidity. The analysis of the relationship between the aerosol particle compositions and 72-h backward air-mass trajectories suggests that ambient aerosols at Tokchok Island are strongly affected not only by seawater from the Yellow Sea but also by anthropogenic pollutants emitted from China and the Seoul–Incheon metropolis, resulting in the dominance of complex secondary aerosol particles.  相似文献   
1000.
建立了重铬酸钾褪色法和硫酸铬显色法直接比色测定CODcr的方法,重铬酸钾褪色法测定范围10-700mg/L,检出限7.0mg/L,三次平行测定CODcr值为417mg/L样品,标准差为2.6mg/L,回收率为96.6%;硫酸铬显色法的测定范围30-1200mg/L,检出限为23.0mg/L,三次平行测定CODcr值为987mg/L,标准差为22.3mg/L,回收率为96.3%,两种方法都优于HJ/T399-2007推荐的方法。  相似文献   
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