污泥活性炭对复合染料的脱色及其重金属浸出毒性

用自制的污泥活性炭处理亚甲基蓝与酸性品红组成的染料废水,研究了pH、吸附时间、温度等因素对复合组分染料废水脱色率的影响,测试分析了污泥活性炭在处理亚甲基蓝与酸性品红复合组分染料废水过程中的重金属浸出毒性。结果表明:与处理单一组分染料废水相比较,处理复合染料废水时pH的影响较为复杂,2种染料在污泥活性炭上存在竞争吸附,但是污泥活性炭对复合组分染料的脱色效果较好。污泥活性炭对复合染料的吸附过程符合Langmuir型吸附。在处理染料废水的过程中,污泥活性炭中的重金属镉、锌及铬会浸出,重金属镉、锌的浸出浓度符合国家标准,但铬的浸出浓度已接近国家标准上限。     

Studies on atmospheric degradation of diazinon in the EUPHORE simulation chamber

The gas phase atmospheric degradation of diazinon has been investigated at the large outdoor European Photoreactor (EUPHORE) in Valencia, Spain. The rate constant for reaction of diazinon with OH radicals was measured using a conventional relative rate method with di-n-buthylether as reference compound being k = (3.5 ± 1.2) × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ at 302 ± 10 K and atmospheric pressure. The available evidence indicates that tropospheric degradation of diazinon is mainly controlled by reaction with OH radicals, and that the tropospheric lifetime with respect to the OH reaction is estimated to be around 4 h whereas its lifetime with respect to the photolysis is higher than 1 d under our conditions. Significant aerosol formation was observed following the reaction of diazinon with OH radicals, and the main carbon-containing products detected in the particle phase were hydroxydiazinon, hydroxydiazoxon and 2-isopropyl-6-methyl-pyrimidinyl-4-ol.     

Monitoring plastic ingestion by the northern fulmar Fulmarus glacialis in the North Sea

The abundance of plastics in stomachs of northern fulmars from the North Sea is used in the OSPAR Ecological Quality Objective (EcoQO) for marine litter. The preliminary EcoQO defines acceptable ecological quality as the situation where no more than 10% of fulmars exceed a critical level of 0.1 g of plastic in the stomach. During 2003-2007, 95% of 1295 fulmars sampled in the North Sea had plastic in the stomach (on average 35 pieces weighing 0.31 g) and the critical level of 0.1 g of plastic was exceeded by 58% of birds, with regional variations ranging from 48 to 78%. Long term data for the Netherlands since the 1980s show a decrease of industrial, but an increase of user plastics, with shipping and fisheries as the main sources. The EcoQO is now also used as an indicator for Good Environmental Status in the European Marine Strategy Framework Directive.     

Biodegradation of Coir and Sisal Applied in the Automotive Industry

This paper discusses the results of biodegradability tests of natural fibers used by the automotive industry, namely: coir, coir with latex, and sisal. The biodegradation of coir, coir with latex, and of sisal fibers was determined by monitoring the production of carbon dioxide (CO₂) (IBAMA—E.1.1.2, 1988) and fungal growth (DIN 53739, 1984). The contents of total extractives, lignin, holocellulose, ashes, carbon, nitrogen and hydrogen of the fibers under study were determined in order to ascertain their actual content and to understand the results of the biodegradation tests. The production of CO₂ indicated low biodegradation, i.e., about 10% in mass, for all the materials after 45 days of testing; in other words, no material inhibited glucose degradation. However, the percentage of sisal fiber degradation was fourfold higher than that of coir with latex in the same period of aging. The fungal growth test showed a higher growth rate on sisal fibers, followed by coir without latex. In the case of coir with latex, we believe the fungal growth was not intense, because natural latex produces a bactericide or fungicide for its preservation during bleeding [1]. An evaluation of the materials after 90 days of aging tests revealed breaking of the fibers, particularly sisal and coir without latex, indicating fungal attack and biodegradation processes.     

Are exploited mangrove molluscs exposed to Persistent Organic Pollutant contamination in Senegal, West Africa?

The surface sediments, two bivalves (Arca senilis and Crassostera gasar) and three gastropods (Conus spp., Hexaplex duplex and Pugilina morio) from two Senegalese stations, Falia (Sine-Saloum Estuary) and Fadiouth (Petite Côte), were analyzed for their pollutant organic persistent contamination (polychlorinated biphenyls PCBs; organochlorinated pesticides OCPs; polybrominated diphenyl ethers PBDEs). Results revealed significant levels of PCBs, DDTs and lindane in mangrove sediments ranging from 0.3 to 19.1, 0.3 to 15.9, and 0.1 to 1.9 ng g⁻¹ d.w., respectively. Among the other POPs analysed, only hexachlorobenzene, heptachlor and trans-nonachlor for OCPs, as well as BDE47 and BDE99 congeners for PBDEs were detected at very low concentrations, generally not of concern. POP levels and patterns were in good accordance with literature data available for other tropical developing countries. A seasonal quantitative difference was highlighted with higher levels of PCBs and DDTs in sediments after the wet season, likely due to the strong wash-out of residues from inland to the marine ecosystems during the rainy season. The observed pattern of DDT and its metabolites pointed out probable recent applications of DDT for public health emergencies in Senegal. Exploited molluscs were exposed to the same POP compounds as those measured in sediments. They presented OCP levels within the same range as in sediments, while significant higher concentrations of PCBs were observed in shellfish soft tissues revealing a higher bioaccumulation potential mainly due to the lipophilicity of these compounds. Finally, the influence of the reproduction cycle on POP levels through lipid content variations was highlighted, minimizing potential differences in POP bioaccumulation between shellfish species. From an ecotoxicological and public health point of view, results from this study revealed that POPs in sediments from the Petite Côte and the Sine-Saloum Estuary would not cause toxic effects and impairments in molluscs from these regions, and that no potential risk exists for human, especially local populations, through mangrove shellfish consumption.     

好氧反硝化去除低浓度NOx的动力学模型研究

在好氧条件下,对利用生物滴滤塔(bio-tricklingfilter,BTF)反硝化净化废气中NOx的过程进行了理论模型探讨,并用实验结果进行了验证.在分析NOx在BTF内传质以及生物降解过程的基础上,建立了NOx在气相和生物膜相的质量守恒方程,结合Fick定律和好氧条件下的Monod微生物反应动力学方程,最终得到了...     

安徽省城市化进程中的碳排放影响因素研究——基于STIRPAT模型

通过对安徽省2000~2011年能源消费碳排放量及碳排放强度进行了测算分析,并基于STIRPAT模型,运用因子主成分回归方法,构建影响城市化进程中碳排放增长的驱动因子模型,对城市化进程中碳排放影响因子进行定量分析研究。研究表明：安徽省2000~2011年能源消费碳排放量呈逐年递增态势,碳排放强度和能源强度均逐年递减态势;安徽省在城市化快速进程中,第二产业产值、第三产业产值、城镇人口比重、城镇建成区面积、城镇居民人均可支配收入每增加1%时,碳排放总量将增加1.208 8%、0.202 0%、0.502 3%、4.793 8%、1.066 0%;当能源强度每下降1%时,碳排放总量将减少0.120 2%;城镇建成区面积扩张、工业化水平提升促进了能源的消耗,成为碳排放的主要驱动因素。鉴于此,提出严格控制城市发展用地规模、通过科技创新推动能源利用效率提高及开发利用新能源、优化产业结构及提高三次产业占GDP比重、建设紧凑型低碳城市、倡导低碳绿色生态的生产消费模式等政策建议,为实现建设生态文明以及实现“生态安徽”与“美丽安徽”目标提供科学依据,也可为中尺度（省级行政区）城市化进程中碳排放的研究提供示范     

三峡水库中下游水体氮磷时空变化与机制分析

2010年每月定期测定了位于三峡水库中下游的云阳、巫山、秭归和三斗坪段的TN、NH4 N、NO3 N和TP浓度。结果表明：4个段面水质中的TN、NH4 N、NO3 N和TP浓度空间差异不显著,但季节变化显著,TN和TP的季节变化呈单峰格局,分别在5月和7月达到最大值;NH4 N的季节变化则呈双峰格局,主要的峰值出现在7、8月,次要的峰值出现在3、4月。4个地点低水位期（3~8月）的TN、NH4 N、NO3 N和TP浓度都高于高水位期（9月~次年2月）。主要因为在低水位期,长江上游和三峡库区的降雨量大,入库流量显著增加,污染物主要来自长江上游入库的非点源污染和水库两岸农田施用农药化肥造成的面源污染。三峡水库三期蓄水后,水库水质与前两期蓄水后的水质变化不大,水质仍然保持良好,高水位期为Ⅲ类水质,低水位期为Ⅳ类水质     

基于虚拟同步发电机的微电网控制策略研究

针对微电网中的分布式电源出力的间歇性导致微电网频率及电压不稳定的问题,通过建立虚拟同步发电机(V irtual Synchronous Generator, VSG)控制系统的数学模型,设计了一种基于频率控制、电压控制和功率控制的反馈控制器,并给出了相应的控制方法;通过理论分析分布式电源的频率、电压特性及其对微电网频率、电压稳定性的影响,提出了能够有效抑制分布式电.源功率波动,提高微电网电能质量的控制策略。仿真结果表明:VSG能稳定地控制微电网频率、电压,具有很好的稳态性。     

Potential of copper-tolerant grasses to implement phytostabilisation strategies on polluted soils in South D. R. Congo

Phytostabilisation (i.e. using plants to immobilise contaminants) represents a well-known technology to hamper heavy metal spread across landscapes. Southeastern D.R. Congo, Microchloa altera, a tolerant grass from the copper hills, was recently identified as a candidate species to stabilise copper in the soil. More than 50 grasses compose this flora, which may be studied to implement phytostabilisation strategies. However, little is known about their phenology, tolerance, reproductive strategy or demography. The present study aims to characterize the Poaceae that may be used in phytostabilisation purposes based on the following criteria: their ecological distribution, seed production at two times, abundance, soil coverage and the germination percentage of their seeds. We selected seven perennial Poaceae that occur on the copper hills. Their ecological distributions (i.e. species response curves) have been modelled along copper or cobalt gradients with generalised additive models using logic link based on 172 presence-absence samples on three sites. For other variables, a total of 69 quadrats (1 m²) were randomly placed across three sites and habitats. For each species, we compared the number of inflorescence-bearing stems (IBS) by plot, the percentage of cover, the number of seeds by IBS and the estimated number of seeds by plot between sites and habitat. Three species (Andropogon schirensis, Eragrostis racemosa and Loudetia simplex) were very interesting for phytostabilisation programs. They produced a large quantity of seeds and had the highest percentage of cover. However, A. schirensis and L. simplex presented significant variations in the number of seeds and the percentage of cover according to site.