丘陵区坡面土壤有机碳及颗粒有机碳分布特征

测定了紫色丘陵区疏林地、荒草地和坡耕地三种土地利用方式下土壤有机碳和颗粒有机碳含量,探讨不同利用方式与坡位下土壤有机碳和土壤颗粒有机碳的分布特征.结果表明:不同土地利用方式下上坡位和中坡位土壤有机碳和颗粒有机碳含量均为疏林地＞坡耕地＞荒草地,而在下坡位两者含量变化差异较大;不同土地利用方式下各坡位土壤剖面有机碳含量均是在0～5 cm层富集,颗粒有机碳的含量也表现出一定在剖面分异性;不同土地利用方式土壤颗粒有机碳分配比例为(0.74±0.01)～(0.34±0.02),不同土地利用方式之间土壤颗粒有机碳分配比例差异较小.相关分析表明,不同利用方式下土壤有机碳、全氮和颗粒有机碳含量之间均呈显著的相关性.     

Biozide in Gebäudefassaden – ökotoxikologische Effekte, Auswaschung und Belastungsabschätzung für Gewässer

Background, aim and scope Sources of organic micropollutants occuring in surface waters are often unknown. Regarding environmental risk assessments for surface waters, construction materials have as till now, not been given much consideration, although biocides used as preservatives are known to reach urban storm water runoff. The study focused on biocides for facades coatings and aimed (1) to determine ecotoxicological effect values, (2) to quantify the leaching behaviour and (3) to assess the environmental risk for surface waters using a dynamic transport model. Materials and methods Eight biocides used in resin based facade coatings were investigated. Some biocides are substances known as pesticides for agricultural purposes like diuron, carbendazim and terbutryn. Ecotoxicological effect values for aquatic organisms were determined for every biocide. Leaching of four biocides from a render under UV-irradiation has been investigated in the laboratory including the influence of varying temperatures. Using 80 irrigation intervals over 28 days, facade runoff was sampled and followed by biocide chemical analysis. The total losses were calculated based on the concentration patterns. These data were used for modelling the transport of cybutryn from facades to surface waters. Biocide specific effect values and leaching characteristics have been taken into consideration. Results Acute and chronic effect values as well as predicted no effect concentrations for the investigated biocides indicate their high potential to affect aquatic organisms. The leaching of four biocides (diuron, terbutryn, cybutryn, carbendazim) from the facade render under the experimental conditions delivers high concentrations in the beginning followed by an exponential decrease. Rising temperature increased the concentration of biocides in the runoff. The total losses were between 7?% and 29?% depending on the substances. More than half of the losses occur in the runoff within the first 15 min of runoff from a 60 min irrigation cycle. The modelling result for cybutryn underlines its high environmental risk for small surface waters. Discussion The leaching of the biocides, their potential ecotoxic effects and persistence show clearly that the environmental risk for surface waters and soils seems to be high for certain biocides; whereas for others the risk seems to be significantly lower. With respect water quality criteria, polluted facades runoff has to be diluted before runoff can enter the discharge. Diuron and carbendazim are however also used as pesticides and preservatives for other materials and cybutryn is also used as an antifouling agent. All pathways have to be evaluated in order to identify relevant sources and to act more efficiently with respect to water and soil protection. Conclusions Concentrations with high environmental risk are expected at new facades, especially at facades with thermal insulation. With the given low predicted no effect concentrations in a range of a few ng/L and large amounts of biocides applied in paints and renders, the environmental risk for common biocides used in facade coatings has to be investigated in laboratory and field scale. It seems plausible that source control measures as the most efficient and sustainable precautionary principle need to be evaluated. Recommendations and perspectives Biocides and additives applied in construction materials have to be taken into consideration as relevant sources when evaluating the quality of storm water runoff, discharge into urban areas and the impact to soil and surface waters. A sustainable construction material management and storm water management are required. It is expected that ongoing laboratory and field studies with exterior paints, renders and flat sheets for waterproofing containing biocides and additives will give further insight into their environmental impact.     

催化超临界水氧化法去除焦化废水中的氨氮

采用催化超临界水氧化技术处理焦化废水.实验结果表明:升高反应温度、增加反应压力、延长反应时间可提高废水中氨氮去除率;在反应时间为60 s、反应压力为30 MPa、反应温度为460℃的最佳实验条件下,未加入催化剂时的氨氮去除率为53.7％,加入催化剂后,氨氮去除率大幅提高,以MnO2为催化剂时氨氮去除率为86.9％,以CuSO4为催化剂时氨氮去除率为92.4％.     

危险辨识方法的研究

介绍了一种新的危险辨识方法 ,应用该方法可以系统地发现潜在的事故序列、事故的起始事件以及相应控制系统的薄弱环节 ,为进一步的风险分析奠定基础     

Optimising the preparation of activated carbon from digested sewage sludge and coconut husk.

Preparation of activated carbon from sewage sludge is a promising way to dispose of sewage sludge as well as to produce a low-cost adsorbent for pollutant removal. This research work aimed to optimise the condition for activated carbon preparation from anaerobically digested sewage sludge with the additive coconut husk. The sewage sludge sample was mixed with the additive coconut husk. The preparation condition variables investigated involved the concentration of the ZnCl2 solutions, heating temperature, dwell time and heating rate in pyrolysis and the mixing ratio of coconut husk to sewage sludge. Surface area, pore size distribution, aqueous phenol adsorption capacity and the production yield of the final products were determined and compared. Experimental results revealed that low concentrations of ZnCl2 solution tended to improve the microporosity of the final product. Heating temperature had a considerable impact on the surface area, pore size distribution and phenol adsorption capacity of the final products, whereas dwell time and heating rate performed comparatively insignificantly. The effect of increasing the mixing ratio of coconut husk to sewage sludge was principally to increase the microporosity of the final products. The activated carbon with the highest BET surface area was produced with the activation of 5 M ZnCl2 solution and, thereafter, pyrolysis at a heating temperature of 500 degrees C for 2 h with a heating rate of 10 degrees C/min. The mixing ratio of 1:4 in terms of coconut husk to sewage sludge based on their dried weights was found to be most cost effective.     

注水残渣固化修路技术研究

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。     

氮缺乏引起的非丝状菌活性污泥膨胀

采用SBR法处理啤酒废水,研究了进水中不同有机物与总氮的比值(以BOD/N计)条件对活性污泥膨胀的影响.结果表明,在进水BOD/N为100/4的条件下,污泥的沉降性能良好;在进水BOD/N分别为100/3和100/2时,均发生由高含水率的粘性菌胶团过量生长引起的非丝状菌膨胀.在进水BOD/N为100/0.94的条件下,发生的非丝状菌膨胀最为严重.试验中还研究了氮缺乏条件下污泥微生物对氮源和磷源的利用率以及COD去除率的变化.     

碳酸钡生产过程中废弃物的回收与利用

本文主要探讨BaCO_3生产过程中废弃物综合利用的途径     

多配位基螯合离子交换纤维的研究及其进展

离子交换纤锥作为具有高吸附佐的吸附材料，在金属离子的分离、富集、回收等方面，以及在水净处理净化处理领域得到了迅速的发展及应用，引起了人们的极大兴趣。本文对近十几年来离子交换纤维的合成方法路线、性能研究以及在痕量元素的分离、富集和水处理方面的应用进行了综述，并对目前离子交换纤维的研究中存在的问题提出了一些看法。     

对一起管道疏通机造成触电事故的分析

１９９９年７月１２日,在我市发生一起触电事故,死亡青工正名。当日上午７：４０某家庭服务队接到某饭店电话,说饭店２楼后厨下水道堵塞,请派人去疏通。于是贾××和另一名工人带上管道疏通机前去作业。８时许,２人来到现场,从墙上配电盘下方接好电源,然后试机准备...