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41.
The level of arsenic (As) contamination and the geochemical composition of groundwater in Shuklaganj area located on the banks of the Ganges Delta of Kanpur-Unnao district were elucidated. Samples (n?=?59) were collected from both India Mark II hand pumps (depth, 30-33 m) and domestic hand pump tube wells (10-12 m) located within 5 km from the banks of Ganges. Samples were analyzed for various parameters, including total inorganic As, sulfate, nitrate, alkalinity, ammonia, and iron. Hydrochemistry of the groundwater aquifer was studied through the trilinear plots between monovalent and divalent cations and anions. In Indian mark II hand pumps, arsenic concentration ranged from below detection limit to 448 μg/L. Most of the samples contained both As(III) and As(V). The pH of the samples ranged from 7.1 to 8.2. Except for a few, most of the samples were reducing in nature as evident by their negative oxidation reduction potentials. A positive correlation for arsenic with iron, ammonia, and dissolved organic carbon shows the probability of biodegradation of organic matter and reductive dissolution of Fe oxyhydroxide processes to leach As in aquifers. For confirmation of the suggested arsenic mobilization mechanism, the presence and absence of sulfate-reducing bacteria and iron-reducing bacteria were also tested.  相似文献   
42.
Journal of Material Cycles and Waste Management - Recycling of mixed waste, including plastic and rubber, by the blending process is one of the promising sustainable routes. In this paper, the...  相似文献   
43.
Two years (Jan. 2000 - Dec. 2001) data on the seasonal studies of phytoplanktonic diversity of Kitham lake (Sur Sarovar) Agra revealed the presence of 73 algal species. A limited number of these were recorded throughout the year, while others were distributed in different seasons mainly in winter and summer seasons. During winters, Chlorophyceae was the most dominant group followed by Bacillariophyceae. On the other hand, Cyanophyceae and Euglenophyceae were the most dominant during summers. Certain species e.g. Pandorina morum, Pediastrum tetras, Gonium sp., Chlorella vulgaris, Scendesmus quadricauda, Oedogonium cardiocum, Synedra ulna, Oscillatoria agardhii and Euglena gracillis were recorded throughout the year. Chlorella, Stigeoclonium, Pandorina, Micratinium, Oscillatoria, Anacystis, Nitzschia and Cymbella were found to be good indicators of water pollution.  相似文献   
44.
45.
The present study discusses ion sources and assesses the chemical quality of groundwater of Doon Valley in Outer Himalayan region for drinking and irrigational purposes. Valley is almost filled with Doon gravels that are main aquifers supplying water to its habitants. Recharged only by meteoric water, groundwater quality in these aquifers is controlled essentially by chemical processes occurring between water and lithology and locally altered by human activities. Seventy-six water samples were collected from dug wells, hand pumps and tube wells and were analysed for their major ion concentrations. The pH is varying from 5.6 to 7.4 and electrical conductivity from 71 to 951 μmho/cm. Groundwater of Doon valley is dominated by bicarbonate contributing 83% in anionic abundance while calcium and magnesium dominate in cationic concentrations with 88%. The seasonal and spatial variation in ionic concentration, in general, is related to discharge and lithology. The high ratio of (Ca + Mg)/(Na + K), i.e. 10, low ratio of (Na + K)/TZ+, i.e.0.2 and also the presence of carbonate lithology in the northern part of valley, is indicative of carbonate dissolution as the main controlling solute acquisition process in the valley. The low abundance of silica content and high HCO?/H?SiO? ratio also supports carbonate dissolution and less significant role of silicate weathering as the major source for dissolved ions in Doon Valley. The analytical results computed for various indices show that water is of fairly good quality, although, hard but have moderate dissolved solid content. It is free from sodium hazard lying in C?-S? and C?-S? class of USSL diagram and in general suitable for drinking and irrigation except few locations having slightly high salinity hazard.  相似文献   
46.
Environmental Science and Pollution Research - Value addition of agro products improves the livelihood opportunities for rural farmers. Cold Storage is one of the techniques to improve the shelf...  相似文献   
47.
Field observations of the Asian longhorned beetle (Anoplophora glabripennis) mating behavior in China suggested that a female-produced contact pheromone was almost certainly involved in sex recognition. Gas chromatography–mass spectrometry (GC-MS) analysis of A. glabripennis adults' whole body cuticular extracts indicates that a series of long-chain hydrocarbons comprise the cuticular waxes of both sexes. Although for the most part the GC profiles are similar for the two sexes, five monounsaturated compounds were consistently more abundant in samples from females than in those from males. These compounds were identified as (Z)-9-tricosene, (Z)-9-pentacosene, (Z)-7-pentacosene, (Z)-9-heptacosene, and (Z)-7-heptacosene in the approximate ratio of 1:2:2:8:1, respectively. Antennal and palpi contact to a polypropylene micro-centrifuge tube coated with a synthetic mixture of the five compounds stimulated copulatory behavior in males.Electronic Supplementary Material  Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material.  相似文献   
48.
The tea aphid, Toxoptera aurantii, also called the “black citrus aphid”, is one of the most destructive insect pests in commercial tea plantations and gardens in southern China. In autumn, declining day length triggers production of winged T. aurantii sexuparae, which produce both winged males and wingless oviparae. Oviparous females then release sex pheromone that attracts potential mates. GC–MS analysis of volatile headspace extracts of T. aurantii oviparae revealed that they emit (4aS,7S,7aR)-nepetalactone (I) and (1R,4aS,7S,7aR)-nepetalactol (II) in a ratio of 4.3–4.9:1. Field-trapping experiments with synthetic I and II singly or as two-component blends of different doses and ratios showed significant attraction of T. aurantii males, as well as weak attraction of sexuparae. Identification of the T. aurantii sex pheromone provides a new opportunity for developing a pheromone-based monitoring and management strategy for the sexual phase of tea aphids and, possibly, the alate sexparous generation in late summer and fall.  相似文献   
49.
Persistence of cypermethrin and chlorpyriphos in okra and soil were studied following the application of pre-mix formulation of insecticides Action 505EC (chlorpyriphos 50%?+?cypermethrin 5%) at single (275?g a.i.?ha?1) and double dose (550?g a.i.?ha?1). The average initial deposits of chlorpyriphos in okra were observed to be 0.07 and 0.15?mg?kg?1 in single and double dose, respectively, which dissipated to 92% after 10 days for both the dosages. Residues of soil under okra crop were found to be 0.15?mg?kg?1 at the single and 0.36?mg?kg?1 at the double doses. These residues persisted up to 3 days at single and 5 days at double dose. The half-life (t 1/2) periods of chlorpyriphos on okra and soil were observed to be 0.6 days and 1.9 days for single and double dose, respectively. Residues of chlorpyriphos reached below detectable level (BDL) of 0.01?mg?kg?1 in okra fruits after 7 days at single dose and in 15 days in double dose. In soil, residues of chlopyriphos persisted up to 5 and 7 days in single and double dose, respectively. Following foliar applications of a insecticide formulation (Action 505EC, (chlorpyriphos 50%?+?cypermethrin 5%) on okra at @ 275 and 550?g active ingredient (a.i.)?ha?1 resulting in active applications of chlorpyriphos at the rate of 250 and 500?g a.i.?ha?1 the average initial deposits of chlorpyriphos in okra were observed to be 0.07 and 0.15?mg?kg?1, respectively. These residue levels dissipated to 92% after 10 days at both the dosages. Residues of soil under the okra crop were found to be 15?mg?kg?1 at the single and 36?mg?kg?1 at the double dose. The residues persisted up to 3 days at the single and 5 days at the double dose. The half-life (t 1/2) periods of chlorpyriphos on okra were observed to be 0.6 days for application rates, and 1.9 days for soil. Okra fruits and soil samples collected on the 7th and 15th day after application did not show any chlorpyriphos residues above their determination limits of 0.01 and 0.005?mg?kg?1, respectively.  相似文献   
50.
Waste management practices in three apex government hospitals of Agra viz., Sarojini Naidu Medical College, Lady Lyall Maternity Hospital and District Hospital were studied during January 2004-January 2005. Data were collected with the help of (i) personal observations of the waste treatment and disposal practices and (ii) assessment of knowledge, attitude and practices of working personnel with the help of questionnaires. The results obtained indicated lack of knowledge and awareness regarding legislations on bio-medical waste management even among qualified hospital personnel. None of these hospitals were equipped with higher technological options e.g. incinerator autoclave, microwave and had no facilities to treat the liquid waste generated inside the hospital. It is concluded that generation and implementation of a waste management policy institutiona/organizational set up, training and motivation must be given paramount importance to meet the current needs and standards of bio-medical waste management in these hospitals.  相似文献   
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