Environmental Science and Pollution Research - The exhaust emissions from the compression ignition engines are harmful to both human beings and the environment. After-treatment devices placed in... 相似文献
Water and soil pollution by toxic heavy metals (HMs) is increasing globally because of increase in population, industrialization and urbanization. It is a burning problem for the public, scientists, academicians and politicians how to tackle the toxic contaminants which jeopardize the environment. One possible solution for pollution abatement is a bioremediation-effective and innovative technology that uses biological systems for treatment of contaminants. Many bacteria synthesize indole-3-acetic acid (IAA) which is a product of l-tryptophan metabolism and belongs to the auxin class of plant growth-promoting hormone. The present study aimed at assessing the resistance pattern of wastewater bacteria against multiple HMs and plant growth promotion activity associated with IAA. A Gram-negative bacterial strain Pseudomonas aeruginosa KUJM was isolated from Kalyani Sewage Treatment Plant. This strain showed the potential to tolerate multiple contaminations such as As(III) (50 mM), As(V) (800 mM), Cd (8 mM), Co (18 mM), Cu (7 mM), Cr (2.5 mM), Ni (3 mM) and Zn (14 mM). The capability of IAA production at different tryptophan concentration (1, 2, 5 and 10 mg mL−1) was determined, and seed germination-enhancing potential was also estimated on lentil (Lens culinaris). Such type of HM-resistant, IAA-producing and seed germination-enhancing P. aeruginosa KUJM offer great promise as inoculants to promote plant growth in the presence of toxic HMs, as well as plant inoculant systems useful for phytoremediation of polluted soils. Hence, P. aeruginosa KUJM finds significant applications in HM-contaminated poor agricultural field as well as in bioremediation of HM-contaminated wastewater system.
In the analysis and design of municipal solid waste (MSW) landfills, there are many uncertainties associated with the properties of MSW during and after MSW placement. Several studies are performed involving different laboratory and field tests to understand the complex behavior and properties of MSW, and based on these studies, different models are proposed for the analysis of time dependent settlement response of MSW. For the analysis of MSW settlement, it is very important to account for the variability of model parameters that reflect different processes such as primary compression under loading, mechanical creep and biodegradation. In this paper, regression equations based on response surface method (RSM) are used to represent the complex behavior of MSW using a newly developed constitutive model. An approach to assess landfill capacities and develop landfill closure plans based on prediction of landfill settlements is proposed. The variability associated with model parameters relating to primary compression, mechanical creep and biodegradation are used to examine their influence on MSW settlement using reliability analysis framework and influence of various parameters on the settlement of MSW are estimated through sensitivity analysis. 相似文献
A sensitive adsorptive stripping voltammetric method for the determination of simeton with universal buffer solution has been described. The method was based on the adsorption accumulation of simeton at a hanging mercury drop electrode. The overall reduction process is under controlled diffusion. The adsorptive peak was observed at ?0.8 V vs SCE in acidic solution 2 < pH < 6. The peak response was characterized with respect to pH, accumulation potential, time, and scan rate. The calibration plot was found to be linear from 1.13 × 10???5 to 3.5 × 10???8 M with a limit of detection of 2.0 × 10???8 M. Finally, the method has been applied for the determination of simeton in its formulations and vegetable samples. 相似文献
This study emphasizes on identification of source and accessing the spatial variation of dissolved heavy metals (Cu, Cd, Fe, Ni, Pb and Zn) in the rivers of Sundarban Biosphere Reserve India, the UNESCO world heritage site. ANOVA (Analysis of Variance), PCA (Principal Component Analysis) as well as FA (Factor Analysis) are used for assessing the significant difference in means of metals concentration among the sites and understanding the sources of these pollutants. Three principal components with cumulative variance of 32, 55, and 73 %, show that Pb, Ni and Cd are closely associated with each other indicating an anthropogenic origin of these metals. Heavy metal evaluation index (HEI) values indicate that areas close to densely populated sites are affected by elevated metals concentration due to anthropogenic activities. The ratio between the concentration of Cd, Ni and Pb in sites and the maximum respective permissible limit for these metals for conserved habitat is Log10 normalized to understand the threats of these pollutants over the distributaries of Sundarbans. Pb pollution is prevalent in the areas that rely on the fossil fuel-operated boats, for transport, whereas higher Cd concentration is found in the areas dependent on rechargeable batteries to meet their energy demand. So these anthropogenic activities and mal-practices may be responsible for the heavy metal pollution in this region. The study concludes that gradual increase in metal pollution in river water due to anthropogenic activities, particularly Pb and Cd, could have a negative impact on the conserved flora and fauna of this ecosystem. 相似文献
This study investigated the feasibility of using fresh activated sewage sludge as inoculum for the microbial valorization of segregated municipal solid waste and evaluated the quality of organic soil amendment generated. Organic fraction of municipal solid waste, which consisted of vegetative (vegetable, fruit and flower) wastes was seeded with activated sewage sludge and processed by rapid aerobic microbial treatment. Efficacy of microbial valorization process and quality of final product were assessed by physico-chemical analysis. Suitability of final product was assessed with regard to heavy metal content, pesticide residues, microbiological quality and phytotoxicity. Quality of the soil amendment generated was compared with the control product generated with a commercial microbial inoculum. Phytotoxicity experiments indicated the stimulatory effect of sewage sludge seeded soil amendment on plant growth but inhibition was observed in closed growth test due to the evolution of gaseous phytotoxic agents. The study suggests that segregated municipal solid waste can be effectively valorized with activated non-dewatered sewage sludge as inoculum and the quality of soil amendment generated was comparable to compost intended for unrestricted applications. 相似文献
Journal of Material Cycles and Waste Management - Generation of municipal solid waste (MSW) depends upon lifestyle, urbanization and income level of population. Solid waste management is one of the... 相似文献
Environmental Science and Pollution Research - Antimicrobials of natural origin are proving to be an effective solution to emerging antimicrobial resistance and its physiological side effects.... 相似文献