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1.
Ten out of the 12 new EU members, used to belong to the so-called “former eastern block”, with a post WWII environmental policy radically different from the tendencies followed in Western Europe. The lack of conservation regulations has resulted in a rather harmful industrialization, regarding natural resources and environmental quality. While air pollution transfer is a phenomenon of transboundary level, there is a particular interest in examining the contribution of the new EU member states to the environmental pressure faced by the older member states and vice versa. The current study utilises the official data for almost 20 years published by the European Monitoring and Evaluation Program concerning the transboundary transfer of NOx and SO2 in order to analyse the situation and discuss the present and future environmental policy regarding air pollution. 相似文献
2.
聚合氯化铝与有机高分子复合絮凝剂的形态分布研究——AlFerron和~(27)AlNMR相结合 总被引:11,自引:0,他引:11
主要研究了Al-Ferron逐时络合比色法和^27Al-NMR法应用于聚合铝与有机高分子复合絮凝剂形态分布的测定,结果表明,两种方法分别测定的Alb和Al13的结果具有一定的相关性;聚合铝与有机高分子复合后其形态分布发生了一定的变化,Alb(或Al13)的含量有所降低,但仍是优势形态,Ala(或Al单)的含量基本保持不变。 相似文献
3.
Effects of low temperature on aluminum(III) hydrolysis: Theoretical and
experimental studies 总被引:1,自引:0,他引:1
In this study, the effects of low temperature on aluminum(III) (Al) hydrolysis were examined both theoretically and experimentally by constructing a solubility diagram for amorphous aluminum hydroxide (Al(OH)3(am)) and a distribution diagram of hydrolyzed Al species. First, thermodynamic data of Al species at 4 degrees C were calculated from that at 25 degrees C. A well confirmed polymeric Al species, AlO4Al12(OH)24(7+)(Al13), was involved in building the diagrams and, correspondingly, the non-linear simultaneous equations with 13 degrees were resolved. Secondly, polarized Zeeman atomic absorption spectrophotometry (AAS), 27Al nuclear magnetic resonance (NMR) spectroscopy, and ferron-based spectrophotometry were applied for constructing the practical diagrams. The results show that a decrease of temperature from 25 to 4 degrees C caused the Al(OH)3(am) boundary on the solubility diagram to shift toward the alkaline side by about 1.0 pH unit and the minimum solubility of Al(OH)3(am) to reduce by 1.0 log unit. The distribution diagram indicates that the monomeric Al, Al13, and solid-phase Al(OH)3 were alternately the predominant species with the increase of pH value during Al hydrolysis. At 25 degrees C, Al13 was the dominant species in a pH range of 4.0 to 4.5, whereas at 4 degrees C, All3 was the leading species in a pH range spaced from 4.5 to 6.3. The predominant species changed from the monomeric Al to the solid-phase Al(OH)3 over the range of 1.8 pH units at 4 degrees C in comparison with the range of 0.5 pH unit at 25 degrees C. 相似文献
4.
After a prolonged drafting and consultation process, South Africa has introduced a new royalty charge to holders of mineral development rights. Deciding on an acceptable royalty is a complex process, especially when it targets deceptive economic rents. This is achieved with a variable royalty rate that slides in tandem with mine profitability. The base is sales revenue and to compensate for the need to charge for the mineral in its unprocessed form, refined production is charged at a lower rate. The aim of this paper is to discuss the Royalty Act in the context of its background, the underlying theory and fundamental principles. This paper argues that the fundamental principles on which the Act is based are sound, but raises a concern on potentially high compliance and reporting costs. 相似文献
5.
聚合氯化铝与有机高分子复合絮凝剂的形态分布研究--Al-Ferron和27Al-NMR相结合 总被引:2,自引:0,他引:2
主要研究了Al Ferron逐时络合比色法和2 7Al NMR法应用于聚合铝与有机高分子复合絮凝剂形态分布的测定 .结果表明 ,两种方法分别测定的Alb 和Al13 的结果具有一定的相关性 ;聚合铝与有机高分子复合后其形态分布发生了一定的变化 ,Alb(或Al13 )的含量有所降低 ,但仍是优势形态 ,Ala(或Al单)的含量基本保持不变 . 相似文献
6.
铝的水解聚合形态分析方法研究 总被引:52,自引:14,他引:52
本文主要探讨了铝的水解聚合形态的两种测定方法,即A1-Ferron逐时络合比色法和^27A1 NMR核磁共振法。扼要地说明了A1-Ferron逐时络合比色法中不同比色-缓冲的配制及其测定结果,以及^27A1 NMR法中大、小管测量方法及其测定结果。最后对这两种铝的水解聚合形态分析方法的相关性作了对比。 相似文献
7.
本文对Al-Ferron逐时络合比色法和~(27)AI-NMR法对PASC和PAC中铝的形态分布的测定结果进行了对比分析和讨论.结果表明,在PAC中,Al_(13)和AI_b之间具有良好的对应关系,Al_(13)/Al_b比值为1.0左右 但对PASC而言,情况有所不同,在低碱化度(B)和低Al/Si摩尔比情况下,Al_(13)和Al_b之间不存在对应关系,Al_(13)和Al_b比值远远小于1.0,随着B值和Al/Si摩尔比的升高,Al_(13)/Al_b比值逐渐趋近于1.0.这意味着在低B值和低Al/Si摩尔比情况下,由于聚硅酸与铝水解聚合产物间的相互作用,形成了铝硅复合新产物,该新产物对PASC中铝的形态分布产生了影响. 相似文献
8.
The synthesis of silver doped nano-particulate titanium dioxide (Ag/TiO2) using a microemulsion method and an investigation of its photocatalytic activity for the degradation of Acid Red 27 in distilled water under UV-irradiation is reported. The prepared Ag/TiO2 is characterized using transmission electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. The size of the Ag nanoparticles is around 5–15?nm, with almost uniform distribution on the TiO2 particles. The efficiency of the photocatalytic process is evaluated to establish the optimum conditions, found to be at 2?wt% of Ag loading on TiO2, catalyst dosage of 400?mg?L?1, and calcination temperature of 300°C. Complete decolorization of the dye solution on Ag/TiO2 was observed in 20?min of UV irradiation in the optimum conditions. 相似文献
9.
Duu-Jong Lee Chin-Yu Lee Jo-Shu Chang Qiang Liao Ay Su 《International Journal of Green Energy》2015,12(10):998-1004
The microbial fuel cell (MFC) was employed to convert reductive potential in sulfate-laden wastewaters to electricity via reducing sulfate to sulfide by sulfate-reducing bacteria and then oxidizing sulfide to sulfur by exoelectrogens. The excess sulfide presented in the anodic solution inhibited the activities of functional strains in MFC. This study proposed the use of a two-anode system, with a sulfate-reducing bacteria anode and an exoelectrogen (C27) anode in the anodic cell, to efficiently convert reductive potential of sulfate into electricity. The microbial community of sulfate-reducing bacteria anode and the electrochemical characteristics of the studied MFCs were reported. 相似文献
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