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81.
Clerodendrum indicum (L.) is one of the important medicinal plants, originating in India. The plant is used as medicine for bronchitis, asthma and different immunological disease. Micro-propagation is a quick method, producing a huge number of plants. Apical leaf of Clerodendrum indicum (L.) was used as an explant for callogenesis. The combinations of different plant growth regulators (2,4-D, NAA, KN) in MS (Murashige and Skoog) medium produced two types of calli: one was friable and loose and the other was green, embryogenic and compact. Heavy metals cause pollution and health hazards. The plant absorbs heavy metals, which is very useful for controlling environmental pollution. Iron is a major nutrient for both plants and animals, but hyper accumulation of iron is injurious to health. Calli were used to study the optimum conditions of iron uptake in presence of different chemical environments. The different environments were created by using different chemical reagents such as (HCL, HNO3, H3PO4 and KNO3). Iron (III) was spiked with radioactive Fe-59 and dynamics of uptake was followed by measuring radioactivity by gamma-ray spectrometer. The best condition of iron uptake corresponded to 1 mol L?1 KNO3 after 4 hour of equilibration.  相似文献   
82.
Fluvalinate was applied on chickpea crop at (i) 0.056, (ii) 0.112 and (iii) 0.56 kg a.i. ha‐1 to evaluate its rate of dissipation. Two major degradation products of fluvalinate formed on the crop were identified and characterised as phenoxybenzoic acid and 2‐[2‐chloro‐4‐(trifluoromethyl)anilino]‐3‐methylbutanoic acid. They were estimated in day‐5 and day‐10 samples of chickpea crop as their methyl esters by gas liquid chromatography.  相似文献   
83.
• UVA pre-irradiation to TiO2 NPs enhanced its toxicity toward plant A. cepa. • UVA TiO2 NPs increased intracellular ROS, resulting in more cell damage. • Cell death enhanced cell permeability and increased uptake of NPs. • Being highly toxic (EC50 = 0.097 µmol/L), TC did not increase ROS generation. • Even at a low dose, TC enhanced the toxic potential of TiO2 NPs significantly. Usage of titanium dioxide nanoparticles (TiO2 NPs) and tetracycline (TC) has increased significantly in the present era. This leads to their release and accumulation in the environment. Both the compounds, individually, can have adverse toxic effects on the plants. Their binary mixtures can increase this degree of damage. The present study aimed to evaluate the toxicity of both the contaminants in individual and binary mixtures in Allium cepa. Further, the toxicity of TiO2 NPs upon UVA pre-irradiation was also measured. Results showed that UVA pre-irradiated NPs (UVA-TiO2 NPs) had a significant decrease in cell viability than their non-irradiated counterparts (NI-TiO2), denoting an increase in photocatalytic activity upon UVA pre-irradiation. Very low concentrations of TC (EC10 = 0.016 µmol/L) mixed with TiO2 NPs significantly increased the toxicity for both UVA-TiO2 and NI-TiO2 NPs. Intracellular ROS generation was significantly high for UVA-TiO2 NPs. However, TC did not have any effects on ROS production. Both the compounds exhibited genotoxic potential in A. cepa. Different chromosomal abnormalities like anaphase bridges, telophase bridges, laggard chromosomes, binucleate cells, etc. were observed. The binary mixture of UVA-TiO2 NPs and TC showed the highest chromosomal aberrations (64.0%±1.26%) than the mixture with NI-TiO2 or the individual contaminants. This decreased significantly after recovery (46.8%±1.92%), denoting the self-repair processes. This study proved that UVA-TiO2 NPs were more toxic and could be enhanced further when mixed with a sub-lethal concentration of TC. This work will help to assess the risk of both compounds in the environment.  相似文献   
84.
The global crisis of the hazardous electronic waste (E-waste) is on the rise due to increasing usage and disposal of electronic devices. A process was developed to treat E-waste in an environmentally benign process. The process consisted of thermal plasma treatment followed by recovery of metal values through mineral acid leaching. In the thermal process, the E-waste was melted to recover the metal values as a metallic mixture. The metallic mixture was subjected to acid leaching in presence of depolarizer. The leached liquor mainly contained copper as the other elements like Al and Fe were mostly in alloy form as per the XRD and phase diagram studies. Response surface model was used to optimize the conditions for leaching. More than 90% leaching efficiency at room temperature was observed for Cu, Ni and Co with HCl as the solvent, whereas Fe and Al showed less than 40% efficiency.  相似文献   
85.
This paper deals with the accidental release of chlorine from bonnet of a valve in a bullet installed in a chloro-alkali industry, and the probable causes of the accident and the ensuing sequence of events. Emergency procedures are also discussed. Finally, in the conclusions reached at some useful recommendations, which has been drawn for industrial facilities handling chlorine.  相似文献   
86.
Large quantities of sediment are transported by the River Ganga (The Ganges) particularly In its deltaic region. Attempts have been made to study the physicochemical parameters of the bottom sediments of the River Ganga at various depths at Kamarhati and along the banks of the River Ganga in the lower deltaic region. The results give vital information regarding the pollution load carried by the river and the enrichment of its sediments with nutrients such as P, N and other substances such as C and S (as sulphates). The mobilization of the P, N, C and S (as sulphates) in the sediments is compared with their natural abundance. The enrichment of the river beds with P, the interaction of the sediment and the characteristics of the sediments are ascertained. Some aspects of the phosphorus cycle and its importance are also discussed. The recycling and reuse of sediments for agricultural purposes have been proposed in order to restore ecological imbalances due to nutrient loss.Mrs M. Chattopadhyay (née Ray) and D. Mukherjee are both post-doctorate ex-senior research scholars within the Department of Chemistry, Kalyani University, where Professor S.C. Lahiri was until recently head of department. Mr S.K. Bhattacharya is director of the Ganga Action Plan Sector, Calcutta Metropolitan Development Authority, Unnayan Bhavan (1st floor), Salt Lake, Calcutta 700 091, India. The information given in this paper is supplementary to that provided by certain of the same authors inThe Environmentalist 13(3), 199–210.  相似文献   
87.
Theory states that an optimal forager should exploit a patch so long as its harvest rate of resources from the patch exceeds its energetic, predation, and missed opportunity costs for foraging. However, for many foragers, predation is not the only source of danger they face while foraging. Foragers also face the risk of injuring themselves. To test whether risk of injury gives rise to a foraging cost, we offered red foxes pairs of depletable resource patches in which they experienced diminishing returns. The resource patches were identical in all respects, save for the risk of injury. In response, the foxes exploited the safe patches more intensively. They foraged for a longer time and also removed more food (i.e., had lower giving up densities) in the safe patches compared to the risky patches. Although they never sustained injury, video footage revealed that the foxes used greater care while foraging from the risky patches and removed food at a slower rate. Furthermore, an increase in their hunger state led foxes to allocate more time to foraging from the risky patches, thereby exposing themselves to higher risks. Our results suggest that foxes treat risk of injury as a foraging cost and use time allocation and daring—the willingness to risk injury—as tools for managing their risk of injury while foraging. This is the first study, to our knowledge, which explicitly tests and shows that risk of injury is indeed a foraging cost. While nearly all foragers may face an injury cost of foraging, we suggest that this cost will be largest and most important for predators.  相似文献   
88.
Supervised field trials were conducted at four different agro-climatic zones in India to evaluate the dissipation pattern and risk assessment of flubendiamide on tomato. Flubendiamide 480 SC was sprayed on tomato at 48 and 96 g active ingredient (a.i.) ha?1. Samples of tomato fruits were drawn at 0, 1, 3, 5, 7, 10, 15, and 20 days after treatment. Quantification of residues was done on a high-performance liquid chromatography (HPLC) device with a photo diode array detector. The limit of quantification (LOQ) of this method was found to be 0.01 mg kg?1 while limit of detection (LOD) being 0.003 mg kg?1. Residues of flubendiamide were found below the determination limit of 0.01 mg kg?1 in 20 days at both the dosages in all the locations. The half-life of flubendiamide at an application rate of 48 g a.i.?ha?1 varied from 0.33 to 3.28 days and at 48-g a.i. ranged from 1.21 to 3.00 days. On the basis of data generated under the All India Network Project on Pesticide Residues, a preharvest interval (PHI) of 1 day has been recommended, and the flubendiamide 480 SC has been registered for its use on tomato by the Central Insecticide Board and Registration Committee, Ministry of Agriculture, Government of India. The maximum residue limit (MRL) of flubendiamide on tomato has been fixed by the Ministry of Health and Family Welfare, Government of India under Food Safety Standard Authority of India, as 0.07 μg g?1 after its risk assessment.  相似文献   
89.
Ken-Betwa river link is one of the pilot projects of the Inter Linking of Rivers program of Government of India in Bundelkhand Region. It will connect the Ken and Betwa rivers through a system of dams, reservoirs, and canals to provide storage for excess rainfall during the monsoon season and avoid floods. The main objective of this study is to identify erosional and inundation prone zones of Ken-Betwa river linking site in India using remote sensing and geographic information system tools. In this study, Landsat Thematic Mapper data of year 2005, digital elevation model from the Shuttle Radar Topographic Mission, and other ancillary data were analyzed to create various thematic maps viz. geomorphology, land use/land cover, NDVI, geology, soil, drainage density, elevation, slope, and rainfall. The integrated thematic maps were used for hazard zonation. This is based on categorizing the different hydrological and geomorphological processes influencing the inundation and erosion intensity. Result shows that the southern part of the study area which lies in Panna district of Madhya Pradesh, India, is more vulnerable than the other areas.  相似文献   
90.
Environmental Management - Rural households in South Asia’s coastal deltas face numerous livelihood challenges, including risks posed by climatic variability and extreme weather events. This...  相似文献   
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