锰污染土壤根际微生物分离及耐Mn2+特性

为了研究锰污染土壤的生物修复,在湘潭锰矿不同植物根际土壤中分离得到7株真菌和8株细菌,依次命名为F1-7和B1-8。经耐锰性能测定,获得高耐锰性真菌3株,F3-5、细菌3株,B1、B2和B7。其中,F3耐锰浓度最高可达600mmol/L,细菌B7最高耐锰浓度为80 mmol/L。当Mn2+浓度小于300 mmol/L时,对3种真菌的生长均具有一定的促进作用,高于此浓度时,产生较大程度的抑制作用。在低Mn2+浓度(20~40 mmol/L)条件下,Mn2+对3种细菌的生长均表现出一定的促进作用,尤其是对B2作用明显。当Mn2+浓度逐渐增加到80 mmol/L时,抑制作用明显。在Mn2+浓度为300mmol/L时,F3对锰的吸附率约为60%,达到峰值。而在Mn2+浓度为60 mmol/L时,细菌B2对锰的吸附率约为70%,达最大值。     

投加聚氨酯泡沫微生物固定化载体的SBBR脱氮除磷实验研究

研究投加聚氨酯泡沫微生物固定化载体的SBBR脱氮除磷效果及机理.在SBR中填充聚氨酯泡沫微生物固定化载体,形成序批式生物膜反应器(SBBR).SBBR以实际生活污水为处理对象,在A/O运行工况下对微生物进行培养驯化,并在SBBR运行稳定时研究其脱氮除磷效果.研究结果表明,SBBR中的聚氨酯泡沫微生物固定化载体在空间上形...     

铁炭内电解-厌氧-好氧工艺处理阿维菌素废水的试验研究

血清瓶毒性试验表明 ,AVM对厌氧消化产生强烈的抑制作用。AVM废水经铁炭内电解预处理后 ,COD和AVM的去除率分别达到 19.5 %和 6 8.5 % ,可大大降低废水的毒性。预处理出水再经UASB +生物接触氧化反应器进一步处理 ,当生化系统进水COD为 6 0 0 0— 6 5 0 0mg/L时 ,出水COD为 2 5 0— 2 80mg/L ,总COD去除率达到 95 .6 % ,出水达到生物制药行业排放标准     

膜生物反应器处理微污染水源水的研究与应用现状

膜生物反应器及其组合工艺能实现水源水中微污染物的有效去除,是一种新型高效水处理工艺.总结了膜生物反应器处理微污染水源水的研究与应用现状、污染物去除效果和机制;在分析膜污染机制基础上归纳了膜污染控制和污染膜清洗方式,展望了膜生物反应器在给水领域应用需克服解决的技术难点.     

Boreal bog plants: nitrogen sources and uptake of recently deposited nitrogen

The main goals of this study were to determine the delta15N signature of quantitatively important boreal bog plants as basis for discussing their N sources, and to assess the effects of five different 3 year N treatments (i.e. 0, 5, 10, 20 and 40 kg N ha(-1) year(-1)) on the bog plants and surface peat at different depths (i.e. 0, 5, 10, 20 and 40 cm) by using 15N as tracer. Plants and peat were analyzed for N concentration, 15N natural abundance and 15N at.%. From the results we draw three main conclusions: First, the relative importance of different N sources is species-specific among bog plants. Second, an annual addition of 5 kg N ha(-1) year(-1) was sufficient to significantly increase the N concentration in Sphagnum mosses, liverworts and shallow rooted vascular plants, and an annual addition of 40 kg N ha(-1) year(-1) during 3 years was not sufficient to increase the N concentration in deep rooted plants, although the 15N content increased continuously, indicating a possible longer term effect. Third, an annual addition of 40 kg N ha(-1) year(-1) during 3 years increased the N content in surface peat at depths of 5 and 10 cm, but not at depths of 20 and 40 cm, indicating the capacity of the living Sphagnum mosses and the surface peat to take up deposited N, and thereby function as a filter.     

Ocean pollution from land-based sources: East China Sea, China

The environment of East China Sea (ECS) has been faced by huge stresses from anthropogenic activities and population growth in the Yangtze River drainage basin and the areas along the coasts. Improper use of natural resources and short-term economic objectives have resulted in severe environmental degradation in a fairly short time frame and the degradation has now reached a level where the health and well being of the coastal populations are threatened. The main pollutants are inorganic nitrogen, phosphate, oil hydrocarbons, organic matters and heavy metals. Nutrients cause eutrophication of the coastal waters and the estuarine area and very often stimulate the occurrence of red tides. The environmental pollution of Yangtze River basin directly impact on the state of the marine environment in the ECS. The ecosystem stability is maintained by a steady water discharge from the river, that mixes with the marine salty water in the estuary, and the sediment loads from the river that balance ocean erosion in the delta and its adjacent coastal area. The large-scale water transfer and dam constructions in the Yangtze River basin will change this basis. For the ECS the challenge is to reverse the negative processes taking place and to restore ecosystem balance. The main challenge is to integrate socioeconomic and environmental decision making in order to promote sustainable development. A better understanding of the driving forces in society that cause these environmental pressures is required in order to overcome these obstacles. International cooperation may be an important contributor to the progress and in particular provide access to financial, technological, scientific and human resource assistance.     

Dissolved organic matter fractions formed during composting of winery and distillery residues: evaluation of the process by fluorescence excitation-emission matrix

The aim of the present paper is to assess the maturity degree reached by different samples of several mixtures from winery and distillery residues composted using the Rutgers composting system, by means of excitation-emission matrix (EEM) fluorescence spectroscopy. The composts were sampled once a week for about 200d. EEM spectra indicate the presence of different fluorophores. The fluorescence intensities of these peaks show trends related to the maturity of the composting samples selected. The "contour density" of EEM maps is strongly modified through time. We have used the quantitative method of fluorescence regional integration (FRI). The EEMs were delineated into five excitation-emission regions. The degree of compost maturity could be correlated with the percentage of the volumetric integration under the EEM within each region. Further refinement of these techniques should provide a relatively rapid method for assessing the suitability of the compost to soil application.     

PAH and soot emissions from burning components of medical waste: examination/surgical gloves and cotton pads

This is a laboratory investigation on the emissions from batch combustion of representative infectious ("red bag") medical waste components, such as medical examination latex gloves and sterile cotton pads. Plastics and cloth account for the majority of the red bag wastes by mass and, certainly, by volume. An electrically heated, horizontal muffle furnace was used for batch combustion of small quantities of shredded fuels (0.5-1.5 g) at a gas temperature of approximately 1000 degrees C. The residence time of the post-combustion gases in the furnace was approximately 1 s. At the exit of the furnace, the following emissions were measured: CO, CO2, NOx, particulates and polynuclear aromatic compounds (PACs). The first three gaseous emissions were measured with continuous gas analyzers. Soot and PAC emissions were simultaneously measured by passing the furnace effluent through a filter (to collect condensed-phase PACs) and a bed of XAD-4 adsorbent (to capture gaseous-phase PACs). Analysis involved soxhlet extraction, followed by gas chromatography-mass spectrometry (GC-MS). Results were contrasted with previously measured emissions from batch combustion of pulverized coal and tire-derived fuel (TDF) under similar conditions. Results showed that the particulate soot) and cumulative PAC emissions from batch combustion of latex gloves were more than an order of magnitude higher than those from cotton pads. The following values are indicative of the relative trends (but not necessarily absolute values) in emission yields: 26% of the mass of the latex was converted to soot, 11% of which was condensed PAC. Only 2% of the mass of cotton pads was converted to soot, and only 3% of the weight of that soot was condensed PAC. The PAC yields from latex were comparable to those from TDF. The PAC yields from cotton were higher than those from coal. A notable exception to this trend was that the three-ring gas-phase PAC yields from cotton were more significant than those from latex. Emission yields of CO and CO2 from batch combustion of cotton were, respectively, comparable and higher than those from latex, despite the fact that the carbon content of cotton was half that of latex. This is indicative of the more effective combustion of cotton. Nearly all of the mass of carbon of cotton gasified to CO and CO2 while only small fractions of the carbon in latex were converted to CO2 and CO (20% and 10%, respectively). Yields of NOx from batch combustions of latex and cotton accounted for 15% and 12%, respectively, of the mass of fuel nitrogen indicating that more fuel nitrogen was converted to NOx in the former case, possibly due to higher flame temperatures. No SO2 emissions were detected, indicating that during the fuel-rich combustion of latex, its sulfur content was converted to other compounds (such as H2S) or remained in the soot.     

灭多威的环境毒理研究进展

本文对近年来有关灭多威的环境毒理研究进行了综述。内容包括，在土壤和水中的归趋；在作物上的残留；在高等动物体内的代谢；对土壤生物群落的影响；对水生生物、天敌和有益节肢动物、高等动物和人以及植物的毒性。