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291.
The present study was conducted to determine the physico-chemical properties and heavy metal contents in soils under three land uses (agricultural, riverbank and roadside) from areas situated around rivers (Beas and Sutlej) in Punjab, India. Heavy metal contents in wheat samples (grain and fodder) growing in the area were also analyzed in order to find out potential human health risk through wheat consumption. The studied soils under the three land uses were found to be basic in nature with sandy texture, low soil organic matter and other soil nutrients. Comparatively higher amounts of soil nutrients were observed in soils under agricultural land use as compared to riverbank and roadside land uses. The amounts of heavy metals (Cr, Cu, Co and Pb) analyzed in soils were lower than the various national and international maximum permissible limits, but heavy metal contents observed in wheat fodder samples exceeded the maximum permissible limits for fodder. The soil-to-plant metal bioaccumulation factor was found to be highest for Cu (3.812 for soil–wheat grain and 1.874 for soil–wheat fodder), which showed the bioaccumulation of heavy metals from soils to crops, and the wheat straw-to-grain translocation factor was found to be highest for Co (4.375). The hazard index calculated to assess non-carcinogenic health risks was found above 1 for children, meaning that the wheat grains can pose health risks to children.  相似文献   
292.
Environmental Science and Pollution Research - The study was intended to investigate heavy metal contamination levels in the rice grown in the vicinity of the mining areas of Singhbhum Copper Belt,...  相似文献   
293.
Improperly managed organic waste constitutes a serious environment threat across the globe. This has led to a worldwide struggle to strike a balance between the rapid generation of such wastes and protection of the environment. With the unique advantages of lower operational and maintenance costs compared with other waste management technologies, the use of vermicomposting to manage organic wastes has been increasing rapidly in recent years. Still, some factors (e.g., characteristics of substrate composition before and after treatment) are in need of additional, specific studies so that researchers can better understand the metabolism involved in the process. Vermicomposting provides employment opportunities as it protects the environment, augmenting crop productivity when it is used as a fertilizer supplement and helping to maintain ecological balance. Thus, vermicompost plays an important role in the circular economy. This article provides an overview of the research activities that have been conducted on the use of vermicomposts to remove pollutants from the soil, in wastewater treatment, and in organic waste recycling throughout the world. Circular economic assessment has revealed that vermicomposting technology is usually feasible except in certain cases. Most other methods of waste disposal lead to soil deterioration, toxic effects, and increased pollution affecting land, air, water, and living beings, in addition to the sometimes considerable expense of their implementation. Thus, an eco‐friendly method that removes waste in one step is needed. Determining the long‐term performance and sustainable operation of vermicomposting systems still poses a challenge, however, as treatment performance is affected by design parameters, operational conditions, and environmental factors. This article summarizes the factors influencing pollutant removal through the vermicomposting process. Finally, this article highlights additional research that should be conducted on these issues to improve the performance of vermicomposting.  相似文献   
294.
Prevailing scenario of non-biodegradable food packaging materials worldwide was the motivation for this research. More than half of the packaging materials used today are non-biodegradable and lack one or the other feature that keeps it from being an ideal food packaging material. Based on the current need of food grade packaging materials, the present study illustrates the amelioration of the properties of biodegradable chitosan films with the incorporation of zinc oxide (ZnO) nanoparticles in varying concentration. The ZnO nanoparticles (ZnONPs) used as fillers in the chitosan films were synthesized by supersaturation method. They were characterized using UV–visible spectrophotometry, X-ray diffraction and field emission scanning electron microscopy (FE-SEM). The particles were observed to be around 100–200 nm in size. The chitosan films with varying concentration of ZnONPs were synthesized and characterized using Fourier transform infrared spectroscopy and FE-SEM. The films were studied for their thermal stability, water vapor transmission rate (WVTR) and mechanical properties. The thermal stability, as determined by Thermo Gravimetric Analysis and Differential Scanning Calorimetry increased slightly with increasing percentage of embedded ZnONPs while a substantial decrease in WVTR was observed. Mechanical properties also showed improvements with 77% increment in tensile modulus and 67% increment in tensile strength. The antimicrobial activity of the films was also studied on gram positive bacterium Bacillus subtilis (B. subtilis) and gram negative bacterium Escherichia coli (E. coli) by serial dilution method. A twofold and 1.5-fold increment in the antimicrobial activity was observed for B. subtilis and E. coli, respectively, with increased ZnONPs concentration in the films from 0(w/w) to 2%(w/w). Films thus prepared can prove to be of immense potential in the near future for antimicrobial food packaging applications.  相似文献   
295.
The binary mixture of ethanolic extract of powder, hecogenin, tigogenin, seed powder and thymol with synergiats MGK-264 and piperony butoxide in a 1:5 ratio were used against the . It was observed that the toxic effect of these mixtures were time and dose dependent. The binary mixtures of plant molluscicides with synergist were more toxic with respect to the independent toxicity of these plant molluscicides. Maximum synergistic action (10 fold) of MGK-264 and piperonyl butoxide was observed with hecogenin.  相似文献   
296.
Environmental Science and Pollution Research - The effect of the flow and geometric parameters of a dimple-roughened absorber plate on the enactment of solar air collectors (SACs) with air-impinged...  相似文献   
297.
Environmental Science and Pollution Research - Abandoning shredded waste tyre rubber (WTR) in cement-based mixes facilitates safe waste tyre disposal and conserves the natural resources used in...  相似文献   
298.
Environmental Science and Pollution Research - At present, food security is a matter of debate of global magnitude and fulfilling the feeding requirement of?>?8 billion human...  相似文献   
299.
A sulfate-rich flue gas desulfurization scrubber sludge was used as a substitute backfill material in reclamation of an abandoned coal strip mine. The site was surrounded by monitor wells and the material was characterized for leaching behavior using open column experiments. A drain was placed directly beneath the 45 000 ton fill to enable sampling before dilution or attenuation. The column studies indicated that the scrubber sludge would adsorb manganese, iron, aluminium, cobalt, nickel, thallium and zinc contaminants from the water. Changes in pH appear inadequate to explain the removal by precipitation. The groundwater cleaning phenomenon has been confirmed on a field scale by the drain samples. Boron and molybdenum leach from the fly ash was used to fix the scrubber sludge and serve as marker elements enabling calibration of the dispersivity in computer models of the groundwater system at the site. The leachate front appears to be diluted by a factor of 8 : 1 within the first 15 meters. Since boron and molybdenum release are associated only with the first flush, environmental impacts will be minimal. Columns appear to create a time compression effect on the duration of leaching phenomenon. The effect for this site appears to be at least 5 : 1. The columns were effective in predicting which elements would leach or adsorb in the field and in predicting the actual source concentrations. Other shake tests such as the TCLP and the ASTM shake test were found to be less effective at predicting which elements would leach and were not helpful in predicting field concentrations.  相似文献   
300.
The present study was conducted to evaluate the impact of lead toxicity on the growth parameters of spinach and the performance of lead-resistant bacterial isolates under lead stress conditions. Out of four bacterial isolates selected for this study, only two isolates AMB-CD-2 and AMB-CD-4 were selected based on their lead tolerance ability. A polybag experiment was conducted with six treatments and four replications in spinach. The treatments included T1 (RDF + control), T2 (lead acetate), T3 (AMB-CD-2 + lead), T4 (AMB-CD-4 + lead), T5 (AMB-CD-2), and T6 (AMB-CD-4). Results showed that lead contamination significantly decreased plant growth parameters, particularly in the treatment T2 (lead acetate) when compared with other treatments. Similarly, reduced uptake of nitrogen, phosphorus, and potassium (NPK) was recorded in T2. Inoculation with lead-resistant bacteria, AMB-CD-2, significantly improved plant growth parameters (plant height, root fresh weight, shoot fresh weight, root dry weight, shoot dry weight, and root length). The uptake of NPK was higher in T5 (AMB-CD-2) in the absence of lead by approximately 0.81%, 0.37%, and 0.42% than in the control, respectively. Through atomic absorption spectrophotometer analysis, the lead concentration in treatment T2 (control) was about 3.20 mg/g while in treatment T3 (AMB-CD-2 + lead) it was about 1.32 ppm. The 16S rRNA gene sequencing revealed that AMB-CD-2 resembles Brevibacillus parabrevis. The results demonstrate that the lead-resistant bacteria B. parabrevis AMB-CD-2 showed a significant lead reduction of approximately 58.75% compared to the control.  相似文献   
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