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991.
Kirti Bhalla Shashi Bala Singh Rashmi Agarwal 《Environmental monitoring and assessment》2010,167(1-4):515-520
High performance liquid chromatographic (HPLC) method was developed for analysis of seven gibberellins, i.e., GA3, GA4, GA7, GA3 methyl ester, GA7 methyl ester 3,13 diacetate, GA7 methyl ester, and fusaric acid, using an isocratic system. Method was used for estimation of gibberellins from different Fusarium strains. Gibberellins were extracted from 28 strains of Fusarium, out of which six strains of Fusarium were isolated from soil of different parts of India and 22 strains were procured from the Indian Type Culture Collection, Indian Agricultural Research Institute, New Delhi. Extracts were analyzed for qualitative and quantitative estimation of gibberellins by thin layer chromatography and HPLC, respectively. On the basis of quantitative analysis of produced gibberellins by HPLC, they were categorized as low, moderate, and high gibberellin producing strain. For the first time, Fusarium solani was also reported as high GA3 producing strain. 相似文献
992.
Mamta Goyal Durga Nath Dhar S. K. Singh 《Environmental monitoring and assessment》2010,171(1-4):425-427
The variations of Cl???, F???, and Fe?+?+? in the underground water during pre- and post-monsoon periods for 2003 have been examined, for two places in Unnao district, by argentrometric titration method (Sodic Land Reclamation Project Uttar Pradesh 1998) and atomic absorption spectrometry (Sodic Land Reclamation Project Uttar Pradesh 1998). The concentration of these ions falls outside the limits prescribed by the World Health Organization (WHO 1984). 相似文献
993.
Performance evaluation of cement stabilized fly ash-GBFS mixes as a highway construction material 总被引:1,自引:0,他引:1
Fly ash and granulated blast furnace slag (GBFS) are major by-products of thermal and steel plants, respectively. These materials often cause disposal problems and environmental pollution. Detailed laboratory investigations were carried out on cement stabilized fly ash-(GBFS) mixes in order to find out its suitability for road embankments, and for base and sub-base courses of highway pavements. Proctor compaction test, unconfined compressive strength (UCS) test and California Bearing Ratio (CBR) test were conducted on cement stabilized fly ash-GBFS mixes as per the Indian Standard Code of Practice. Cement content in the mix was varied from 0% to 8% at 2% intervals, whereas the slag content was varied as 0%, 10%, 20%, 30% and 40%. Test results show that an increase of either cement or GBFS content in the mixture, results in increase of maximum dry density (MDD) and decrease of optimum moisture content (OMC) of the compacted mixture. The MDD of the cement stabilized fly ash-GBFS mixture is comparably lower than that of similarly graded natural inorganic soil of sand to silt size. This is advantageous in constructing lightweight embankments over soft, compressible soils. An increase in percentage of cement in the fly ash-GBFS mix increases enormously the CBR value. Also an increase of the amount of GBFS in the fly ash sample with fixed cement content improves the CBR value of the stabilized mix. In the present study, the maximum CBR value of compacted fly ash-GBFS-cement (52:40:8) mixture obtained was 105%, indicating its suitability for use in base and sub-base courses in highway pavements with proper combinations of raw materials. 相似文献
994.
Preparation of alinite based cement from incinerator ash 总被引:1,自引:0,他引:1
Alinite based cements have attracted a great deal of attention because these can be produced at considerable energy savings. Alinite has an additional ability to incorporate in its structure various impurity ions and can thus be made using a number of industrial and mining wastes. In this paper, the work done in the preparation of alinite based cements using incinerator ashes is presented. It is shown that alinite cements having strengths comparable to ordinary Portland cement can be successfully prepared by controlling the composition and firing schedule. 相似文献
995.
Surendra N. Singh D. Todd Donavan Sanjay Mishra Todd D. Little 《Journal of environmental psychology》2008,28(4):339-352
Mean and covariance structure (MACS) modeling is used to explore a central question in contemporary environmental psychology: “How should human environments be conceptualized?”. Specifically, an expanded version of the preference model of landscape perception proposed by S. and R. Kaplan is presented. The proposed model not only constitutes a respecification and deepening of the Kaplans’ model but also presents an integrative perspective that simultaneously considers the interrelations among cognitive, motivational, affective, evaluative, and behavioral tendencies in landscape perception. In a series of four studies, we develop and validate multi-item measures of various constructs, test the measure invariances, and the structural model. The findings reveal the crucial role of various constructs that originally were hypothesized by the Kaplans but never included in the model tests. In addition, positive and negative feelings induced by the landscape emerge as antecedents to landscape perception. The implications of these findings are discussed. 相似文献
996.
Dhakate R Singh VS Negi BC Chandra S Rao VA 《Journal of environmental management》2008,88(4):1373-1383
The increasing demand for fresh water has necessitated the exploration for new sources of groundwater, particularly in hard rock terrain, where groundwater is a vital source of fresh water. A fast, cost effective and economical way of exploration is to study and analyze remote sensing data. Interpreted remote sensing data was used to select sites for carrying out surface geophysical investigations. Various geomorphologic units were demarcated and the lineaments were identified by interpretation of remote sensing satellite images. The potential for occurrence of groundwater in the watershed areas was classified as very good, good, moderate and poor by interpreting the images. Sub-surface geophysical investigations, namely vertical electrical soundings, were carried out to delineate potential water-bearing zones. Integrated studies of interpretation of geomorphologic and geophysical data were used to prepare a groundwater potential map. The studies reveal that the groundwater potential of shallow aquifers is due to geomorphologic features and the potential of deeper aquifers is determined by lineaments such as faults and joints. 相似文献
997.
Moti L. Mittal Chhemendra Sharma Richa Singh 《Environmental monitoring and assessment》2014,186(10):6857-6866
This study aims to estimate the emissions of carbon dioxide (CO2), sulfur dioxide (SO2), and nitric oxide (NO) for coal combustion in thermal power plants in India using plant-specific emission factors during the period of 2001/02 to 2009/10. The mass emission factors have been theoretically calculated using the basic principles of combustion under representative prevailing operating conditions in the plants and fuel composition. The results show that from 2001/02 to 2009/10 period, total CO2 emissions have increased from 324 to 499 Mt/year; SO2 emissions have increased from 2,519 to 3,840 kt/year; and NO emissions have increased from 948 to 1,539 kt/year from the Indian coal-fired power plants. National average emissions per unit of electricity from the power plants do not show a noticeable improvement during this period. Emission efficiencies for new plants that use improved technology are found to be better than those of old plants. As per these estimates, the national average of CO2 emissions per unit of electricity varies between 0.91 and 0.95 kg/kWh while SO2 and NO emissions vary in the range of 6.9 to 7.3 and 2.8 to 2.9 g/kWh, respectively. Yamunagar plant in Haryana state showed the highest emission efficiencies with CO2 emissions as 0.58 kg/kWh, SO2 emissions as 3.87 g/kWh, and NO emissions as 1.78 g/kWh, while the Faridabad plant has the lowest emission efficiencies with CO2 emissions as 1.5 kg/kWh, SO2 emissions as 10.56 g/kWh, and NO emissions as 4.85 g/kWh. Emission values at other plants vary between the values of these two plants. 相似文献
998.
Garg SK Tripathi M Kumar S Singh SK Singh SK 《Environmental monitoring and assessment》2012,184(9):5533-5544
The physicochemical analyses of pulp-paper mill effluent revealed that it was dark brown with 1761?±?2.3 color PtCo units having slightly alkaline pH, high biological oxygen demand and chemical oxygen demand values, and contained large quantities of organic and inorganic constituents, well above the prescribed standards. The bacterial growth, color reduction, and dechlorination were evident in all the four sets of experiments with different possible combinations of nutrient supplementation and Pseudomonas putida augmentation. A high degree of decolorization at 29.7% and 27.4% was observed by the effluent native microflora during 48 and 24 h, in unaugmented effluent supplemented with glucose + yeast extract and glucose + peptone, respectively. The extent of decolorization in glucose + yeast extract unaugmented effluent also corresponded with high degree of dechlorination (59.3%) during 60-h incubation (SET III). An appreciable level of growth, decolorization, and dechlorination was evident in nutrient unsupplemented P. putida augmented effluent as well as in the control natural effluent. However, a maximum level of growth response (OD 1.641-1.902) during 36-48 h, removal of color (39.72-48.2%) during 24-36 h, and chloride ions (80.1-83.5%) during 36 h was achieved in P. putida augmented effluent supplemented with glucose + yeast extract or peptone. Therefore, supplementation of effluent with glucose and yeast extract or peptone and concomitant augmentation with P. putida is required for efficient effluent decolorization and detoxification. 相似文献
999.
Keoladeo National Park (KNP) is an important wintering ground for thousands of birds that undertake a perilous journey over the Himalaya to make a seasonal home in a wetland ecosystem. However, this wetland is now getting polluted by various types of contaminants such as pesticides because of the agricultural practices in the catchment area from where the park receives water. Keeping this in mind, the present study has been undertaken to assess the organochlorine pesticide (OCP) residues in the sediments inside and around KNP. Samples were collected from the different blocks of the park. The concentrations of α-HCH, β-HCH, γ-HCH, δ-HCH, S-HCH, aldrin, dieldrin, heptachlor, hept.epoxide, endosulfan-I, endosulfan-II, endo.sulfate, S-endosulfan, endrin, 4,4'-DDE, 4,4'-DDD, and DDT were quantified using gas chromatography with electron capture detection. Analysis showed that the samples were contaminated with the above mentioned pesticides and that the concentration of total OCPs in the sediments varied from 0.1173 (dieldrin) to 5.558 ppm (γ HCH) in the samples collected from inside the park, whereas a range of pesticides varying in concentration from 0.1245 (4,4'-DDD) to 7.54 ppm (γ HCH) was found in samples from outside the park. Residues of S-HCH and S-endosulfan were not detected in any of the sediment samples. The occurrence of pesticides inside the park is a major threat to the park's biodiversity. Eco-friendly agriculture practices with minimal use of inorganic chemicals are suggested to minimize the pesticide residue levels in the park. 相似文献
1000.
The oxides of nitrogen—NO
x
(NO and NO2)—are an important constituent of the troposphere. The availability of relatively higher spatial (0.25° grid) and temporal
(daily) resolution data from ozone monitoring instrument (OMI) onboard Aura helps us to better differentiate between the point
sources such as thermal power plants from large cities and rural areas compared to previous sensors. The annual and seasonal
(summer and winter) distributions shows very high mean tropospheric NO2 in specific pockets over India especially over the Indo-Gangetic plains (up to 14.2 × 1015 molecules/cm2). These pockets correspond with the known locations of major thermal power plants. The tropospheric NO2 over India show a large seasonal variability that is also observed in the ground NO2 data. The multiple regression analysis show that the influence of a unit of power plant (in gigawatts) over tropospheric
NO2 (×1015 molecules/cm2) is around ten times compared to a unit of population (in millions) over India. The OMI data show that the NO2 increases by 0.794 ± 0.12 (×1015 molecules/cm2; annual) per GW compared to a previous estimate of 0.014 (×1015 molecules/cm2) over India. The increase of tropospheric NO2 per gigawatt is found to be 1.088 ± 0.18, 0.898 ± 0.14, and 0.395 ± 0.13 (×1015 molecules/cm2) during winter, summer, and monsoon seasons, respectively. The strong seasonal variation is attributed to the enhancement
or suppression of NO2 due to various controlling factors which is discussed here. The recent increasing trend (2005–2007) over rural thermal power
plants pockets like Agori and Korba is due to recent large capacity additions in these regions. 相似文献