国内外低碳城市建设探讨与对策研究

低碳技术对经济社会变革的推动作用日益显著,建设低碳城市不仅可缓解当前全球气候变化问题,还可提高城市的竞争力。总结了英国、日本、丹麦、美国等国家在低碳城市建设方面的特点,分析了我国低碳城市建设的现状以及面临的主要挑战,针对我国的低碳城市建设提出了建议。     

中部四大城市群（圈）外商直接投资的时空演化与竞争格局

采用熵指数与偏移一分享分析方法,对中部四大城市群近10年来外商直接投资（FDI）的时空演化与竞争格局进行了定量分析。结果表明,中部城市群FDI在不断增长过程中有分散化的总趋势,但城市群之间差异显著,具有阶段性特征;中部城市群FDI偏移增长量逐年增加,城市群之间的偏移增长量远大于城市群内部;高正偏增长城市前期主要集中在武汉城市圈、长株潭城市群,近期转向皖江城市带、东部沿江地带和中原城市群内沿京广、陇海线交汇一带。     

武陵源世界自然遗产地生态旅游资源评价研究

生态旅游资源评价是生态旅游开发的首要问题。根据武陵源世界自然遗产地生态旅游资源分布情况,构建了包括资源价值、景点模式与旅游条件在内的3个评价综合层、10个项目层和11个因子层所组成的评价体系,并采用层次分析法对武陵源生态旅游资源进行了重新审视。评价结果显示,武陵源生态旅游资源的等级为世界级,具备发展生态旅游的优异条件。     

Statistical uncertainty in hazardous terrestrial concentrations estimated with aquatic ecotoxicity data

Since chemicals’ ecotoxic effects depend for most soil species on the dissolved concentration in pore water, the equilibrium partitioning (EP) method is generally used to estimate hazardous concentrations (HC50) in the soil from aquatic toxicity tests. The present study analyzes the statistical uncertainty in terrestrial HC50s derived by the EP-method. For 47 organic chemicals, we compared freshwater HC50s derived from standard aquatic ecotoxicity tests with porewater HC50s derived from terrestrial ecotoxicity tests. Statistical uncertainty in the HC50s due to limited species sample size and in organic carbon–water partitioning coefficients due to predictive error was treated with probability distributions propagated by Monte Carlo simulations. Particularly for specifically acting chemicals, it is very important to base the HC50 on a representative sample of species, composed of both target and non-target species. For most chemical groups, porewater HC50 values were approximately a factor of 3 higher than freshwater HC50 values. The ratio of the porewater HC50/freshwater HC50 was typically 3.0 for narcotic chemicals (2.8 for nonpolar and 3.4 for polar narcotics), 0.8 for reactive chemicals, 2.9 for neurotoxic chemicals (4.3 for AChE agents and 0.1 for the cyclodiene type), and 2.5 for herbicides–fungicides. However, the statistical uncertainty associated with this ratio was large (typically 2.3 orders of magnitude). For 81% of the organic chemicals studied, there was no statistical difference between the hazardous concentration of aquatic and terrestrial species. We conclude that possible systematic deviations between the HC50s of aquatic and terrestrial species appear to be less prominent than the overall statistical uncertainty.     

上海市火电厂烟气污染物控制对雾霾防治分析

介绍了上海雾霾的成分和火电的贡献率。火电厂通过提高除尘效率和烟气脱硫、脱硝建设,在装机容量成倍增长的情况下烟气污染物排放量持续下降,PM2,从2005年占上海的25％降至8．8％。针对新的环保标准,探讨了解决问题的措施,提出了烟气多污染物协同控制技术建议。     

电袋复合除尘器气流分布的研究与应用

针对电袋复合除尘器气流分布存在的问题,提供了一种技术方法,通过工厂模型试验进行了研究分析,并成功应用于实际工程中,发挥了电袋复合除尘器的优势,提高了对细颗粒物粉尘的捕集效果。     

燃煤电厂脱硝还原剂选择原则及用量计算

面向燃煤烟气氮氧化物控制过程,详细阐述了燃煤电厂脱硝技术还原剂选择原则,对不同还原剂方案进行综合比较。根据SCR、SNCR和SCR／SNCR联合工艺三种不同工艺,重点对还原剂用量计算方法进行了综述,为工程技术人员提供参考。     

600 MW机组省煤器灰中等距离气力输送系统改进措施

某电厂省煤器灰气力输送系统投运初期频繁出现堵管和输灰超时的问题。经过分析及调研后,改用双套管输送,优化输送步序,减少输送耗气量,不仅实现了输送系统平稳顺畅,而且避免了灰管过度磨损的现象。     

Bioavailability and dissipation of fluridone under controlled conditions

Abstract

Bioavailability of fluridone, l‐methyl‐3‐phenyl‐5‐[3‐(trifluoromethyl) phenyl]‐4(1H)‐pyridinone, as affected by soil temperature, soil moisture regime, and duration of incubation was investigated in three soil types by grain sorghum (Sorghum bicolor [L.] Moench cv. Abu Sabien) chlorophyll bioassay. Initial loss of fluridone was rapid and dissipation followed first‐order kinetics under most of the incubation treatments investigated. Soil moisture, in general, had a greater impact than soil temperature on dissipation of fluridone. The herbicide dissipated faster at the fluctuating room temperature (18–24°C) than at the constant 10°C in Sonning sandy clay loam (O.M. = 1.2%) and Erl Wood sandy loam (O.M. = 2.5%) but not in Shropshire loamy peat (O.M. = 33%). In the two mineral soils, bioassay‐detectable residues from an initial rate of 1.00 μg/g were least (0.00 ‐ 0.10 μg/g) at 1/2 field capacity (FC) and greatest (0.16 ‐ 0.37 μg/g) at 1/4 FC, 400 days after treatment. At 10°C, the DT₅₀ values (days) at 1/4 FC and 1/2 FC were, respectively, 147 ± 16 and 69 ± 6 for Erl Wood soil, and 257 ± 28 and 51 ± 12 for Sonning soil. In Shropshire soil, concentrations of bioavailable fluridone were least at each bioassay date when soil moisture was maintained at FC, at both temperatures of incubation. At 10°C, herbicide concentrations in the organic soil from an initial rate of 10.00 μg/g were 0.95 and 4.69 μg/g, respectively, at FC and 1/4 FC.     

Dissipation and sorption of six commonly used pesticides in two contrasting soils of New Zealand

We investigated dissipation and sorption of atrazine, terbuthylazine, bromacil, diazinon, hexazinone and procymidone in two contrasting New Zealand soils (0–10 cm and 40–50 cm) under controlled laboratory conditions. The six pesticides showed marked differences in their degradation rates in both top- and subsoils, and the estimated DT₅₀ values for the compounds were: 19–120 (atrazine), 10–36 (terbuthylazine), 12–46 (bromacil), 7–25 (diazinon), 8–92 (hexazinone) and 13–60 days for procymidone. Diazinon had the lowest range for DT₅₀ values, while bromacil and hexazinone gave the highest DT₅₀ values under any given condition on any soil type. Batch derived effective distribution coefficient (K _d ^eff) values for the pesticides varied markedly with bromacil and hexazinone exhibiting low sorption affinity for the soils at either depth, while diazinon gave high sorption values. Comparison of pesticide degradation in sterile and non-sterile soils suggests that microbial degradation was the major dissipation pathway for all six compounds, although little influence of abiotic degradation was noticeable for diazinon and procymidone.