The rapid growth of the population, the technological and industrial boom has brought enormous prob-lems and degradation of the environment. There is a gradual decline in availability of fresh water to be used for irr...The rapid growth of the population, the technological and industrial boom has brought enormous prob-lems and degradation of the environment. There is a gradual decline in availability of fresh water to be used for irrigation in India. As a consequence, the use of urban waste water (UWW) for irrigating agricultural lands is on the rise particularly in peri-urban areas of developing countries. Effective collection and treatment of urban wastewater is a critical problem in a developing country like India. A case study was undertaken to assess the characteristic of the urban waste water and its management in Mysore city and its long-term effect on irrigation. The untreated and treated urban waste water was collected during 2008 and analyzed in the laboratory. The suitability of the UWW for irrigation purposes is then evaluated according to the existing water quality standards and the results were compared with Food and Agriculture organization (FAO) irrigation water quality standards. It is evident from the results, that the current situation is not promising especially regarding the Electrical Conductivity, Total Dissolved Solids, Biochemical Oxygen Demand, Chemical Oxygen Demand, Suspended Solids and heavy metal concentrations and also pH of the treated UWW is exceeding the FAO standards. Among the heavy metals, the concentration of Iron and chromium are exceeding the FAO standards.展开更多
ZnO-MxOy heterostructures (M=Co, Mn, Ni, or In) are fabricated via hydrothermal synthesis method. X-ray diffraction and Fourier-transform infrared spectroscopy analyses endorse the successive formation of the various ...ZnO-MxOy heterostructures (M=Co, Mn, Ni, or In) are fabricated via hydrothermal synthesis method. X-ray diffraction and Fourier-transform infrared spectroscopy analyses endorse the successive formation of the various heterostructures. Field Emission Scanning electron microscope and Brunauer-Emmett-Teller (BET) surface area studies confirm the porous nature of the heterostructures obtained. The band gaps of various heterostructures are calculated that, 3.1, 2.71, 2.64, and 2.19 eV for ZnO-NiO, ZnO-In2O3, ZnO-Co3O4, and ZnO-MnO2, respectively. The photocatalytic activities of the fabricated heterostructures are investigated through the degradation of phenol under direct sunlight irradiation. The results show that the photocatalytic activity is affected by the conduction band (CB) and valence band (VB) positions rather than surface area of ZnO-MxOy heterostructure nanocomposites.展开更多
In the 21st century the fresh water scarcity increased very rapidly due to the urbanization and industrialization process. In these conditions the urban wastewater plays an important role in the water usage criteria. ...In the 21st century the fresh water scarcity increased very rapidly due to the urbanization and industrialization process. In these conditions the urban wastewater plays an important role in the water usage criteria. In this aspect, in all the major cities, wastewater treatment plants have been constructed to treat the urban wastewater in view of decreasing the water scarcity. The presence of nutrients in the wastewater is considered as beneficial to agricultural practices. The contaminants present in the wastewater pose health risks directly to agricultural workers and indirectly to the consumers as the long term application of the wastewater may result in the accumulation of toxic elements in soil and in plants. In this way the heavy metals will circulate among the food chain and food web to cause adverse effects on human health as well as on soil health. In the present study an attempt has been made to study the characteristics of urban wastewater at wastewater treatment plant of Mysore city. And also heavy metal behavior was studied with the analysis of heavy metals in wastewater, Biosolid and receiving soil along with the plants which indicates the uptake of heavy metals.展开更多
Soil is a major reservoir for contaminants as it possesses an ability to bind various chemicals. These chemicals can exist in various forms in soil and different forces keep them bound to soil particles. It is essenti...Soil is a major reservoir for contaminants as it possesses an ability to bind various chemicals. These chemicals can exist in various forms in soil and different forces keep them bound to soil particles. It is essential to study these interactions because the toxicity of chemicals may strongly depend on the form in which they exist in the environment. Another thing is that soil variability and some environmental properties may change in soil and cause leaching of trace toxic elements like heavy metals tightly bound to soil particles. Metals associated with urban soil are of environmental concern because of their direct and indirect effects on human health. The main purposes of this study undertaken in the Mysore city industrial zone were to identify heavy metals with dangerous environmental load and to find out of their environmental impact (Fe, Cr, Cu, Zn, and Ni). The purpose of this work was to provide information on heavy metals concentration in industrial zone soil of Mysore city, India. Soil samples were analyzed for pH, organic matter, and electrical conductivity. Total and available heavy metal concentrations were determined by AAS. In the present study, heavy metal speciation in soil sample carried out were shows that all metals were mainly associated with the oxidizable and residual fraction, which allows us to predict their mobility in the soil sample.展开更多
文摘The rapid growth of the population, the technological and industrial boom has brought enormous prob-lems and degradation of the environment. There is a gradual decline in availability of fresh water to be used for irrigation in India. As a consequence, the use of urban waste water (UWW) for irrigating agricultural lands is on the rise particularly in peri-urban areas of developing countries. Effective collection and treatment of urban wastewater is a critical problem in a developing country like India. A case study was undertaken to assess the characteristic of the urban waste water and its management in Mysore city and its long-term effect on irrigation. The untreated and treated urban waste water was collected during 2008 and analyzed in the laboratory. The suitability of the UWW for irrigation purposes is then evaluated according to the existing water quality standards and the results were compared with Food and Agriculture organization (FAO) irrigation water quality standards. It is evident from the results, that the current situation is not promising especially regarding the Electrical Conductivity, Total Dissolved Solids, Biochemical Oxygen Demand, Chemical Oxygen Demand, Suspended Solids and heavy metal concentrations and also pH of the treated UWW is exceeding the FAO standards. Among the heavy metals, the concentration of Iron and chromium are exceeding the FAO standards.
文摘ZnO-MxOy heterostructures (M=Co, Mn, Ni, or In) are fabricated via hydrothermal synthesis method. X-ray diffraction and Fourier-transform infrared spectroscopy analyses endorse the successive formation of the various heterostructures. Field Emission Scanning electron microscope and Brunauer-Emmett-Teller (BET) surface area studies confirm the porous nature of the heterostructures obtained. The band gaps of various heterostructures are calculated that, 3.1, 2.71, 2.64, and 2.19 eV for ZnO-NiO, ZnO-In2O3, ZnO-Co3O4, and ZnO-MnO2, respectively. The photocatalytic activities of the fabricated heterostructures are investigated through the degradation of phenol under direct sunlight irradiation. The results show that the photocatalytic activity is affected by the conduction band (CB) and valence band (VB) positions rather than surface area of ZnO-MxOy heterostructure nanocomposites.
文摘In the 21st century the fresh water scarcity increased very rapidly due to the urbanization and industrialization process. In these conditions the urban wastewater plays an important role in the water usage criteria. In this aspect, in all the major cities, wastewater treatment plants have been constructed to treat the urban wastewater in view of decreasing the water scarcity. The presence of nutrients in the wastewater is considered as beneficial to agricultural practices. The contaminants present in the wastewater pose health risks directly to agricultural workers and indirectly to the consumers as the long term application of the wastewater may result in the accumulation of toxic elements in soil and in plants. In this way the heavy metals will circulate among the food chain and food web to cause adverse effects on human health as well as on soil health. In the present study an attempt has been made to study the characteristics of urban wastewater at wastewater treatment plant of Mysore city. And also heavy metal behavior was studied with the analysis of heavy metals in wastewater, Biosolid and receiving soil along with the plants which indicates the uptake of heavy metals.
文摘Soil is a major reservoir for contaminants as it possesses an ability to bind various chemicals. These chemicals can exist in various forms in soil and different forces keep them bound to soil particles. It is essential to study these interactions because the toxicity of chemicals may strongly depend on the form in which they exist in the environment. Another thing is that soil variability and some environmental properties may change in soil and cause leaching of trace toxic elements like heavy metals tightly bound to soil particles. Metals associated with urban soil are of environmental concern because of their direct and indirect effects on human health. The main purposes of this study undertaken in the Mysore city industrial zone were to identify heavy metals with dangerous environmental load and to find out of their environmental impact (Fe, Cr, Cu, Zn, and Ni). The purpose of this work was to provide information on heavy metals concentration in industrial zone soil of Mysore city, India. Soil samples were analyzed for pH, organic matter, and electrical conductivity. Total and available heavy metal concentrations were determined by AAS. In the present study, heavy metal speciation in soil sample carried out were shows that all metals were mainly associated with the oxidizable and residual fraction, which allows us to predict their mobility in the soil sample.
