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871.
Russian Journal of Ecology - Abstract—The study of the effect of mycorrhiza symbiosis on the transformation of carbon and nitrogen compounds in soils is important in view of the necessity to...  相似文献   
872.
Russian Journal of Ecology - A simultaneous analysis of the chronographic variation of the mandible of bank vole (Clethrionomys glareolus Shreb.) in three longitudinally distant populations that...  相似文献   
873.
Yang  W.  Deng  D. G.  Meng  X. L.  Zhang  S. 《Russian Journal of Ecology》2019,50(4):352-360
Russian Journal of Ecology - Temporal and spatial variations of phytoplankton community in Lake Erhai were investigated from May 2010 to April 2011. A total of 124 species belonging to 8 phyla and...  相似文献   
874.
Environmental Science and Pollution Research - The rice husk ash (RHA) was used as an alternative source of silica for the synthesis of the functionalized mesoporous material, which was used in the...  相似文献   
875.
Environmental Science and Pollution Research - A natural phenanthrene-degrading consortium CON was inoculated with an exogenous strain Sphingobium sp. (ex Sp. paucimobilis) 20006FA yielding the...  相似文献   
876.
玉米浸泡液制备苏云金杆菌生物杀虫剂的影响因素研究   总被引:2,自引:0,他引:2  
以玉米淀粉生产过程中的浸泡液为培养基,摇瓶发酵培养苏云金杆菌生物杀虫剂,通过一系列单因子试验,考察了不同培养条件(种子液的种龄、接种量、浸泡液的含固率、初始pH值、摇床转速、发酵温度及发酵时间)对苏云金杆菌在玉米浸泡液中的生长(菌数增长与芽孢形成)以及发酵液的生物毒效的影响.研究表明,在最佳摇瓶培养条件(种子液种龄10 h,接种量2%,浸泡液含固量3%,初始pH值7.0~7.5,摇床转速200 r/min,发酵温度30℃)下发酵48 h,活菌数和活芽孢数分别可达到7.9×108 CFU/mL和5.5×108 CFU/mL,毒力效价为698.0 IU/μL.本试验可为生物农药的工业化生产提供实用参数.  相似文献   
877.
近年来,全氟化合物(PFCs)如全氟辛烷磺酸(PFOS)和全氟辛酸(PFOA,其分子结构如图1所示)已经被明确为持久性有机污染物(POPs),并在环境中普遍存在[1].由于PFCs可能具有毒性和生物积聚性,因此,对食品、饮用水、组织、血浆和全血中PFCs分析方法的建立受到越来越多的关注.  相似文献   
878.
Bottled water may not be safer, or healthier, than tap water. The present studies have proved that styrene and some other aromatic compounds leach continuously from polystyrene (PS) bottles used locally for packaging. Water sapmles in contact with PS were extracted by a preconcentration technique called as "purge and trap" and analysed by gas chromatograph-mass spectrometer (GC/MS). Eleven aromatic compounds were identified in these studies. Maximum concentration of styrene in PS bottles was 29.5 μg/L. Apart from styrene, ethyl benzene, toluene and benzene were also quantified but their concentrations were much less than WHO guide line values. All other compounds were in traces. Quality of plastic and storage time were the major factor in leaching of styrene. Concentration of styrene was increased to 69.53 μg/L after one-year storage. In Styrofoam and PS cups studies, hot water was found to be contaminated with styrene and other aromatic compounds. It was observed that temperature played a major role in the leaching of styrene monomer from Styrofoam cups. Paper cups were found to be safe for hot drinks.  相似文献   
879.
The Gulf of Saros in the northeastern Aegean Sea (Turkey) is a relatively unpolluted marine environment. There is almost no industry and only small settlements in the surrounding region. The main sources of fresh water and sediment to the Gulf are the Meric River in the northwest and the Kavak Creek in the east. It has an asymmetric bathymetry with a 10-km-wide shelf to the north and up to 15-km-wide, 700-m-deep trough in the south. Water circulation in the Gulf is characterized by longshore currents and anticyclonic eddies. The Black Sea waters, leaving the Sea of Marmara through the Canakkale Strait, are known to enter the southern Gulf during the summer. The surface sediments on the northern shelf consist mainly of sand, whereas those on the slope and the deep trough are mainly silt and clay. The ranges of Fe, Mn, Cu, Zn, Pb, Ni, and Hg contents of the surface sediments from the Gulf of Saros are 0.25 4.60%, 114 1740 ppm, 6-44 ppm, 23-154 ppm, 2-80 ppm, 14-145 ppm, and 10-130 ppb, respectively. These values are low compared to those from the other neighboring marine environments, indicating the pristine nature of the Gulf in terms of metal pollution. However, most metal and organic carbon (Corg) distributions in the Gulf sediments show the effect of anthropogenic and natural inputs to the northwestern and eastern shelf areas from the Meric River and the Kavak Creek and to the deep trough from the Black Sea waters.  相似文献   
880.
An approach for quantifying the human health risk caused by industrial sources, which, daily or accidentally, emit dangerous pollutants able to impact on different environmental media, is introduced. The approach is performed by the HHRA-GIS tool which employs an integrated, multimedia, multi-exposure pathways and multi-receptors risk assessment model able to manage all the steps of the analysis in a georeferenced structure. Upper-bound excess lifetime cancer risk and noncarcinogenic hazards are the risk measures, the spatial distribution of which is calculated and mapped on the involved territory, once all the pathways and receptors of the study area are identified. A sensitivity analysis completes the calculations allowing to understand how risk estimates are dependent on variability in the factors contributing to risk. The last part of the paper makes use of a case study concerning a working industrial site to put in evidence in which way the designed tool can help local authorities and policy makers in managing risks and planning remedial and reduction actions. The considered geographical area is a hypothetical territory characterized by residential, agricultural and industrial zones. The presence of two sources of contamination, a municipal waste incinerator (MWI) and a contaminated site, are evaluated by the tool application. Various typologies of receptors have been taken into account, each of them characterized by different anatomical and dietary properties. The achieved results are analyzed, compared with acceptable and background values and alternatives of minor environmental impact calculated.  相似文献   
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