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Although the biological effect of non-ionizing (NIR) and ionizing radiation (IR) on plant seed potential is well documented,
the mechanism of this impact is not clear yet. Since cell hydration, a fundamental parameter for determining cell function,
is magneto-sensitive, in present work, a comparative study of extremely low frequencies (ELF) electromagnetic field (EMF),
ELF EMF-modulated millimeter waves, and radiation exposure effects on winter wheat seeds water absorption and dry mass changes
was performed. The seeds were incubated in physiological solutions (PS) for 2 and 72 h. In case of 2-h incubation, the water
absorption determined by osmotic gradients between seeds and bathing medium, PS treated by all these factors leads to changes
of water absorption. While in case of 72-h incubation (when germination processes are in active state) these impact had reversed
character. The obtained data strongly suggest seeds bathing medium as a target through which the biological effects of NIR
and IR are realized. 相似文献
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Silvina Vargas Gil Analia Becker Claudio Oddino Mónica Zuza Adriana Marinelli Guillermo March 《Environmental management》2009,44(2):378-386
Soil microbial populations can fluctuate in response to environmental changes and, therefore, are often used as biological
indicators of soil quality. Soil chemical and physical parameters can also be used as indicators because they can vary in
response to different management strategies. A long-term field trial was conducted to study the effects of different tillage
systems (NT: no tillage, DH: disc harrow, and MP: moldboard plough), P fertilization (diammonium phosphate), and cattle grazing
(in terms of crop residue consumption) in maize (Zea mays L.), sunflower (Heliantus annuus L.), and soybean (Glycine max L.) on soil biological, chemical, and physical parameters. The field trial was conducted for four crop years (2000/2001,
2001/2002, 2002/2003, and 2003/2004). Soil populations of Actinomycetes, Trichoderma spp., and Gliocladium spp. were 49% higher under conservation tillage systems, in soil amended with diammonium phosphate (DAP) and not previously
grazed. Management practices also influenced soil chemical parameters, especially organic matter content and total N, which
were 10% and 55% higher under NT than under MP. Aggregate stability was 61% higher in NT than in MP, 15% higher in P-fertilized
soil, and also 9% higher in not grazed strips, bulk density being 12% lower in NT systems compared with MP. DAP application
and the absence of grazing also reduced bulk density (3%). Using conservation tillage systems, fertilizing crops with DAP,
and avoiding grazing contribute to soil health preservation and enhanced crop production. 相似文献
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河豚毒素检测技术研究进展 总被引:2,自引:0,他引:2
对检测河豚毒素的主要方法包括生物检测方法、理化检测方法、免疫学方法、传感器方法进行了介绍,并对目前检测方法的优缺点进行比较分析。小鼠测定法是河豚毒素检测的标准方法;理化检测法方法准确,但是对设备要求高,前处理严格;免疫学方法费用较高;传感器方法是新方法,还有待进一步规范。各种检测方法都有其优缺点,河豚毒素检测时应根据要求选择方法。 相似文献
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超临界流体技术在化工污染治理中的应用 总被引:4,自引:0,他引:4
对于许多化工产品废物,如塑料、有毒物质、生物污泥和有机废水等,利用传统技术进行处理的效果较差。超临界流体(SCF)技术作为一种清洁环境的新技术,可用于治理化工污染物。SCF作为反应介质或反应物可替代有毒、有害有机溶剂;用作萃取剂,它是一种新型的分离技术;以SCF作移动相的色谱,可提高检测灵敏度和分辨率;将超临界水作为氧化剂,可破坏有机污染物的结构。SCF技术的应用可以大大减少环境污染。 相似文献
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The environmental behavior of the residents depends on their perception of environmental pollution. Hence, it is important for scientific and policy experts to research on the impact of the environmental pollution perception of local residents. Owing to the richness of natural resources, Hancheng coal mine areas are abound in heavy industries, and environmental pollution is serious and typical in this area, thus, the residents are anxious about their health. Using questionnaires, this paper surveys the perception of residents living in the coal mine area. The influential factors of environmental perception were analyzed by the Rank Sum Test. The results were: (1) the majority of the residents in the coal mine area are not satisfied with their living environment. The perception order of pollution severity is: air pollution?>?noise pollution?>?sanitation?>?water pollution. The residents think that pollution is mainly caused by coal processing. Hence, coal mining is not the main reason of the pollution in the coal mine area. (2) Age and length of residence have significant positive effects on perceptions of air, water, and noise pollutions; whereas education has a significant negative effect on perceptions of water and noise pollutions, as well as sanitation. This phenomenon can be explained by the various cultural groups having varied perceptions on the environmental pollution. In addition, proximity to mine has significant negative effect on perceptions of water and noise pollution. In conclusion, the paper discusses the effects of demographical and social factors on the perception of environmental pollution and gives suggestions on the planning and management of the environment. 相似文献
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Stoddard JL 《Environmental management》2004,34(Z1):S61-S70
Ecological regions are areas of similar climate, landform, soil, potential natural vegetation, hydrology, or other ecologically relevant variables. The makeup of aquatic biological assemblages (e.g., fish, macroinvertebrates, algae, riparian birds, etc.) varies dramatically over the landscape, as do the environmental stresses that affect the condition of those assemblages. Ecoregions delineate areas where similar assemblages are likely to occur and, therefore, where similar expectations can be established. For this reason, ecological regions have proven to be an important tool for use in the process of ecological assessment. This article describes four examples of the use of ecological regions in important aspects of environmental monitoring and assessment: (1) design of monitoring networks; (2) estimating expected conditions (criteria development); (3) reporting of results; (4) setting priorities for future monitoring and restoration. By delineating geographic areas with similar characteristics, ecological regions provide a framework for developing relevant indicators, setting expectations through the use of regional reference sites, establishing ecoregion-specific criteria and/or standards, presenting results, focusing models based on relationships between landscape and surface water metrics, and setting regional priorities for management and restoration. The Environmental Protection Agency and many state environmental departments currently use ecoregions to aid the development of environmental criteria, to illustrate current environmental condition, and to guide efforts to maintain and restore physical, chemical and biological integrity in lakes, streams, and rivers. 相似文献
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近年来我国危险化学品环境污染事故频发,如何及时有效地对污染物进行应急控制及消除显得尤为重要。本文基于事件树分析法原理,根据危险化学品理化性质及其环境污染事故的特征,从污染物种类、污染介质和污染物性质三个方面归纳出危险化学品环境污染事故的42种事故情形,给出每种污染事故情形所对应的处理处置技术方案,构建危险化学品环境污染事故应急处理处置技术树。基于Web服务器Apache、PHP语言和MySQL数据库管理系统开发,建立了危险化学品环境污染事故应急处理处置技术库,实现对技术方案方便快速地查询。 相似文献
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Constructed wetlands are artificial wastewater treatment systems consisting of shallow ponds or channels which have been planted
with aquatic plants and which rely upon natural microbial, biological, physical and chemical process to treat wastewater and
are gaining acceptance in the recent years as a viable option for the treatment of industrial effluents and removal of toxic
components. In this study, an attempt was made to compare the efficiency of aquatic macrophytes like Typha sp., Eichhornia sp., Salvinia sp., Pistia sp., Azolla sp. and Lemna sp. to treat the effluents from dairy factory, under laboratory conditions in constructed wetlands. The biological oxygen
demand and chemical oxygen demand of dairy effluent were reduced up to 65.4–83.07% and 70.4–85.3%, respectively, after treatment
with constructed wetland technology. 相似文献
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Multivariate analysis of variance, canonical correlation and canonical discriminate analysis were performed on environmental data collected from the Kuwaiti intertidal zone to determine the statistical relationships between the sediment, chemical, biological, spatial and temporal variables. The quantitative analysis showed that the sediment type was the paramount factor influencing the distribution and composition of the intertidal benthic fauna. The muddy, sandy and rocky shores support three distinct faunal communities. The seasonal variation in the benthic fauna community was not statistically significant but variation in biological data due to differences in transect location and tidal level were significant. This spatial variation has been attributed to differences in sediment and substrate types. The physico-chemical parameters were found to correlate positively with the mud content of the sediments but were unimportant in the overall composition of the intertidal fauna. This paper complements the results reported in Al Bakriet al. (1997–Part I) in establishing a valuable benchmark for assessing environmental impacts and for developing sustainable coastal zone management in Kuwait. The integrated approach outlined here could be adopted to develop a sound basis for the protection and management of coastal environments and resources in similar areas. 相似文献
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Annually, great amounts of cellulose wastes, which could be measured in many billions of tons, are produced worldwide as residues from agricultural activities and industrial food processing. Consequently, the use of microorganisms in order to remove, reduce or ameliorate these potential polluting materials is a real environmental challenge, which could be solved by a focused research concerning efficient methods applied in biological degradation processes. In this respect, the scope of this chapter is to present the state of the art concerning the biodegradation of redundant cellulose wastes from agriculture and food processing by continuous enzymatic activities of immobilized bacterial and fungal cells as improved biotechnological tools and, also, to report on our recent research concerning cellulose wastes biocomposting to produce natural organic fertilizers and, respectively, cellulose bioconversion into useful products, such as: ‘single-cell protein’ (SCP) or ‘protein-rich feed’ (PRF). In addition, there are shown some new methods to immobilize microorganisms on polymeric hydrogels such as: poly-acrylamide (PAA), collagen-poly-acrylamide (CPAA), elastin-poly-acrylamide (EPAA), gelatin-poly-acrylamide (GPAA), and poly-hydroxy-ethyl-methacrylate (PHEMA), which were achieved by gamma polymerization techniques. Unlike many other biodegradation processes, these methods were performed to preserve the whole viability of fungal and bacterial cells during long term bioprocesses and their efficiency of metabolic activities. The immobilization methods of viable microorganisms were achieved by cellular adherence mechanisms inside hydrogels used as immobilization matrices which control cellular growth by: reticulation size, porosity degree, hydration rate in different colloidal solutions, organic and inorganic compounds, etc. The preparative procedures applied to immobilize bacterial and fungal viable cells in or on radiopolymerized hydrogels and, also, their use in cellulose wastes biodegradation are discussed in detail. In all such performed experiments were used pure cell cultures of the following cellulolytic microorganisms: Bacillus subtilis and Bacillus licheniformis from bacteria, and Pleurotus ostreatus, Pleurotus florida, and Trichoderma viride from fungi. These species of microorganisms were isolated from natural habitats, then purified by microbiological methods, and finally, tested for their cellulolytic potential. The cellulose biodegradation, induced especially by fungal cultures, used as immobilized cells in continuous systems, was investigated by enzymatic assays and the bioconversion into protein-rich biomass was determined by mycelial protein content, during such long time processes. The specific changes in cellular development of immobilized bacterial and fungal cells in PAA hydrogels emphasize the importance of physical structure and chemical properties of such polymeric matrices used for efficient preservation of their metabolic activity, especially to perform in situ environmental applications involving cellulose biodegradation by using immobilized microorganisms as long-term viable biocatalysts. 相似文献
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John W. Pyne Dorothy L. Stewart John C. Linehan Roger M. Bean Mathew A. Powell Richard B. Lucke Berta L. Thomas James A. Campbell Bary W. Wilson 《Resources, Conservation and Recycling》1988,1(3-4)
An extracellular fraction from the lignin degrading white-rot fungus, Coriolus versicolor, can biosolubilize leonardite and pretreated lignites in vitro. Leonardite is often found as an overburden to lignite deposits, and is related to humic acid, and is more oxidized than lignites. Extracts from certain fungi such as C. versicolor solubilize leonardite. The biosolubilization activity is at least in part enzymatic in nature. A protein which is at least partly responsible for the solubilization effect has been substantially purified and concentrated by ultrafiltration and ion-exchange chromatography from the broth of an agitated submerged culture of C. versicolor grown in a defined medium. An in vitro coal biosolubilization assay was used to establish the effects of various physical and chemical factors affecting enzyme activity, including temperature and the salt and buffer composition of the reaction mixture. Some initial studies on the mechanism of the enzymatic leonardite biosolubilization reaction are described. 相似文献
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Evaluation of municipal solid waste composting kinetics 总被引:2,自引:0,他引:2
Most modern municipal solid waste (MSW) composting operations have emphasized the enhancement of decomposition of the organic fraction of the waste to comply with strict environmental regulations. This can be achieved once the composting process kinetics are well understood. This study examined process kinetics through experimentation with bench-scale reactors under controlled composting conditions to show the interdependence between biological, chemical and physical factors during composting of MSW. The effects of temperature, moisture content, waste particle size and carbon to nitrogen (C/N) ratio on process kinetics were evaluated. The results obtained revealed that these factors should be carefully controlled in order to achieve optimum process performance. It has been found that the organic matter degradation during composting follows a first-order kinetic model. 相似文献
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Irina Gaus Pascal Audigane Laurent Andr Julie Lions Nicolas Jacquemet Pierre Durst Isabelle Czernichowski-Lauriol Mohamed Azaroual 《International Journal of Greenhouse Gas Control》2008,2(4):605
Geochemistry plays an important role when assessing the impact of CO2 storage. Due to the potential corrosive character of CO2, it might affect the chemical and physical properties of the wells, the reservoir and its surroundings and increase the environmental and financial risk of CO2 storage projects in deep geological structures. An overview of geochemical and solute transport modelling for CO2 storage purposes is given, its data requirements and gaps are highlighted, and its progress over the last 10 years is discussed. Four different application domains are identified: long-term integrity modelling, injectivity modelling, well integrity modelling and experimental modelling and their current state of the art is discussed. One of the major gaps remaining is the lack of basic thermodynamical and kinetic data at relevant temperature and pressure conditions for each of these four application domains. Real challenges are the coupled solute transport and geomechanical modelling, the modelling of impurities in the CO2 stream and pore-scale modelling applications. 相似文献
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Y. R. Mikayelyan N. S. Baghdasaryan A. K. Nikoghosyan S. V. Barseghyan S. N. Ayrapetyan 《The Environmentalist》2012,32(2):179-187
The effects of extremely low-frequency electromagnetic field (ELF EMF) and ELF-modulated millimeter waves (MMW) on physicochemical
properties of physiological solution (PS) at different environmental medium were studied. The existence of frequency “windows”
at 4 Hz and 8 Hz frequencies of ELF EMF and ELF-modulated MMW which have different effects on heat fusion period (HFP), hydrogen
peroxide (H2O2) formation and oxygen (O2) content of water solution and different dependency on temperature, background radiation (BGR) and illumination was shown.
The obtained data allow us to suggest that cell bathing medium serving as a target through which the biological effects of
ELF EMF and ELF-modulated MMW on cells are realized is extra sensitive to environmental factors. Therefore, the variability
of experimental data on EMF biological effects, obtained in different laboratories can be explained by different environmental
conditions of experiments, which very often are not considered adequately. 相似文献