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11.
Nikhilesh Bishoyee Anshuman Dash Anshuman Mishra Sitakant Patra S. S. Mahapatra 《Journal of Polymers and the Environment》2010,18(3):177-187
Fly ash is a solid waste generated in huge quantities from coal fired thermal power stations during the combustion of coal.
In India, less than half of this is used as a raw material for concrete manufacturing and construction; the remaining is directly
dumped on land side as land fill or simply piled up. Only a small fraction of it is used in development of high valued product.
Due to environmental regulations, new ways of utilizing fly ash are being explored in order to safeguard the environment and
provide useful ways for its utilization and disposal. With its richness in various metal oxides, it has tremendous potential
to be utilized as a filler material in polymer composites. These days glass reinforced polyester composites find widespread
application in erosive environment due to several advantages like high wear resistance, strength-to-weight ratio, and low
cost. The cost of the composites can be further brought down using cheaper filler materials. To this end, this work uses fly
ash in composite making and thereby suggests a new way of better utility of this industrial waste. It includes the processing,
characterization and study of the erosion behavior of a class of such fly ash filled polyester-glass fiber composites. The
engineering application of composites demands that it should have high wear resistance, low density and high tensile strength.
In order to assess the behavior of composites satisfying multiple performance measures, a grey-based Taguchi approach has
been adopted. After thorough analysis of factors, optimal factor settings have been suggested to improve multiple responses
viz., erosive wear rate, density, flexural strength and tensile strength. This technique eliminates the need for repeated
experiments; thus saves time and material. The systematic experimentation leads to determination of significant process parameters
and material variables that predominantly influence the multiple responses. 相似文献
12.
Abhilas Kumar Pradhan Rabinarayan Patra 《Environment, Development and Sustainability》2013,15(4):979-997
Several studies have revealed that the presence of heterogeneity amongst the user groups of common property natural resources considerably affects the effectiveness of resource management and their sustainable use. Primary research conducted in six sample villages from three districts of the Indian state Odisha has found that heterogeneity in economic and social dimensions amongst the members of the management committee acts as major determinants in respect of common property forest resource management. The findings of this piece of work reveal that common property forests are best managed in the villages where the management committee is homogeneous by both social and economic considerations; better managed where the committee members are economically homogeneous but socially heterogeneous; and least managed where the members are socially homogeneous but economically heterogeneous. The same result has been obtained from the composite index developed for the user group’s assessment about the functioning of the forest management institutions in the three study districts of the state Odisha. 相似文献
13.
Masto RE Chhonkar PK Singh D Patra AK 《Environmental monitoring and assessment》2008,136(1-3):419-435
Soil quality assessment provides a tool for evaluating the sustainability of alternative soil management practices. Our objective
was to develop the most sensitive soil quality index for evaluating fertilizer, farm yard manure (FYM), and crop management
practices on a semiarid Inceptisol in India. Soil indicators and crop yield data from a long-term (31 years) fertilizer, manure,
and crop rotation (maize, wheat, cowpea, pearl millet) study at the Indian Agricultural Research Institute (IARI) near New
Delhi were used. Plots receiving optimum NPK, super optimum NPK and optimum NPK + FYM had better values for all the parameters
analyzed. Biological, chemical, and physical soil quality indicator data were transformed into scores (0 to 1) using both
linear and non-linear scoring functions, and combined into soil quality indices using unscreened transformations, regression
equation, or principal component analysis (PCA). Long-term application of optimum inorganic fertilizers (NPK) resulted in
higher soil quality ratings for all methods, although the highest values were obtained for treatment, which included FYM.
Correlations between wheat (Triticum aestivum L.) yield and the various soil quality indices showed the best relationship (highest r) between yield and a PCA-derived SQI.
Differences in SQI values suggest that the control (no NPK, no manure) and N only treatments were degrading, while soils receiving
animal manure (FYM) or super optimum NPK fertilizer had the best soil quality, respectively. Lower ratings associated with
the N only and NP treatments suggest that one of the most common soil management practices in India may not be sustainable.
A framework for soil quality assessment is proposed. 相似文献
14.
Pest management researchers currently reappraise the use of inert dust-based insecticides because of the growing problem of environmental pollution and increasing insect resistance associated with conventional insecticides. Diatomaceous earth, which is amorphous micron-sized silica derived from fossilized phytoplankton, has become popular as an alternative insecticidal agent in European countries. In this investigation the insecticidal efficacy of amorphous lipophilic silica nanoparticle was examined on red flour beetle (Tribolium castaneum), a stored grain insect pest. The biosafety of this silica nanoparticle formulation was studied in MRC-5 cell line with water-soluble tetrazolium and lactate dehydrogenase activity assays. Acute oral toxicity of these nanocides was studied in mice model following OECD guidelines for testing of chemicals as well as the effects of particle exposure on mouse blood parameters, serum biochemical levels, and histopathological changes in various organs. 相似文献
15.
G. Durga Rao M. Kumaraswami P. Ezhilarasan V.D. Rao Sivaji Patra 《Chemistry and Ecology》2017,33(3):229-246
Dissolved nutrients, Chl-a and primary productivity were measured from seven transects along the coastal waters of the southeastern Arabian Sea during northeast monsoon. Ten major estuaries were chosen to study the influence of estuarine discharge on the nutrient dynamics in the coastal waters. The mean water discharge of the estuaries in the north (64.8?±?18?×?105?m3?d?1) was found to be higher than those in the south (30.6?±?21.4?×?105?m3?d?1), whereas the nutrient concentrations were found to be higher in the estuaries of the south. The results from the offshore waters were discussed in accordance with the depth contour classification, that is, shelf (depth?≤?30?m) and slope waters (depth?≥?30?m). Our results suggest that the estuarine discharge plays a major role in the nutrient distribution in near shore shelf waters, whereas in shelf and slope waters, it was mainly controlled by in situ biological processes. The inorganic form of N to P ratios were found to be higher than Redfield ratio in slope waters when compared with shelf waters, suggesting that PO43? (<0.15?µmol?L?1) is a limiting nutrient for primary production. The multivariate statistical analysis revealed that the nutrient dynamics in the coastal waters was controlled by both biological and physical processes. 相似文献
16.
Swayamprabha Mishra Monalisa Mohanty Chinmay Pradhan Hemanta Kumar Patra Ritarani Das Santilata Sahoo 《Environmental monitoring and assessment》2013,185(5):4347-4359
The present investigation aims to assess the phytoremediation potential of six aquatic macrophytes, viz. Eichhornia crassipes, Hydrilla verticillata, Jussiaea repens, Lemna minor, Pistia stratiotes and Trapa natans grown in paper mill effluent of JK Paper mill of Rayagada, Orissa, for remediation of heavy metals. The experiment was designed in pot culture experiments. Assessment of physico-chemical parameters of paper mill effluent showed significant decrease in pH, conductivity, total dissolved solids, total suspended solids, chlorine, sulphur, biological and chemical oxygen demand after growth of macrophytes for 20 days. Phytoremediation ability of these aquatic macrophytic species for copper (Cu) and mercury (Hg) was indicated by assessing the decrease in the levels of heavy metals from effluent water. Maximum reduction (66.5 %) in Hg content of untreated paper mill effluent was observed using L. minor followed by T. natans (64.8 %). L. minor showed highest reduction (71.4 %) of Cu content from effluent water followed by E. crassipes (63.6 %). Phytoextraction potential of L. minor was remarkable for Hg and Cu, and bioaccumulation was evident from bioconcentration factor values, i.e. 0.59 and 0.70, respectively. The present phytoremediation approach was considered more effective than conventional chemical treatment method for removing toxic contaminants from paper mill effluent. 相似文献
17.
Mohanty M Pattnaik MM Mishra AK Patra HK 《Environmental monitoring and assessment》2012,184(2):1015-1024
Mine waste water at South Kaliapani usually contains toxic levels of hexavalent Cr(VI). The present in situ study was conducted at South Kaliapani chromite mine area in Orissa state, India, to assess the phytoremediation ability
of three plants, namely, rice (Oryza sativa L.), paragrass (Brachiaria mutica), and an aquatic weed (Eichhornia crassipes), in attenuating Cr(VI) from mine waste water and to correlate the bio-concentration factors (BCF) of Cr. Water hyacinth
(E. crassipes) showed 24% to 54% reduction whereas paragrass (B. mutica) was able to reduce 18% to 33% of Cr(VI) from mine water. This reduction was studied over a period of 100 days of plant growth.
The reduction was observed through a passage of a sum total of 2,000 sq. ft. cultivated plots and ponds separately. Reduction
in Cr(VI) content in mine water varies with plant age as well as with the distance of passage. Cr accumulation and BCF values
increased with high soil Cr levels as well as the age of plants. High BCF and transportation index (Ti) values, i.e., 10,924
and 32.09, respectively, were noted for water hyacinth. The Ti values indicated that the root-to-shoot translocation of Cr
was very high after 100 days of growth. The total accumulation rate was maximum (8.29 mg Cr kg dry biomass − 1 day − 1) in paragrass. The BCF values for roots were noted to be higher than those of leaves, stems, and grains of the 125-day-old
plants. Hence, paragrass and water hyacinth may be used as tools of phytoremediation to combat the problem of in situ Cr contamination. 相似文献
18.
Sharma KK Kalpana Sharma V Gupta P Jaya M Kumar A Singh B 《Environmental monitoring and assessment》2008,137(1-3):179-184
Fipronil termiticide belongs to phenyl-pyrazole class of chemical compounds. It has broad-spectrum activity particularly against
house hold pests such as cockroaches, mosquitoes, locusts, ticks, and fleas at both larval and adult stages. At high dosage
it can be used to control subterranean termites in building foundations. To evaluate long term efficacy against termites the
persistence and vertical distribution of fipronil was studied under natural weather conditions of Dehradun, India. Fipronil
was applied at four concentrations i.e. 0.05, 0.1, 0.25 and 0.5% a.i ha−1 by drenching 17 × 17 in.2 plot prepared as per modified ground board test. Soil samples were collected after 22, 38 and 56 months of treatment up to
the depth of 75 cm. The soil core was cut into five distinct sections i.e. 0–15, 15–30, 30–45, 45–60 and 60–75 cm depth. The
residues were extracted by shaking 20 g soil sample with acetone. The acetone extract was concentrated and cleaned-up over
florisil column. Fipronil residues were estimated on GLC at 220, 260, and 300°C oven, injector and detector temperature respectively.
Fipronil was found to persist beyond 56 months after application. Two metabolites viz. desulfinyl and sulfide-fipronil were
detected in sampling after 22 months of application that also dissipated with time. Fipronil residues were found up to 60 cm
depth. The residues in deeper layers dissipate slowly with time and after 56 months of treatment residues were detected only
up to 30 cm depth. 相似文献
19.
People are exposed to ionizing radiation from the radionuclides that are present in different types of natural sources, of
which phosphate fertilizer is one of the most important sources. Radionuclides in phosphate fertilizer belonging to 232Th and 238U series as well as radioisotope of potassium (40K) are the major contributors of outdoor terrestrial natural radiation. The study of alpha activity in fertilizers, which
is the first ever in West Bengal, has been performed in order to determine the effect of the use of phosphate fertilizers
on human health. The data have been compared with the alpha activity of different types of chemical fertilizers. The measurement
of alpha activity in surface soil samples collected from the cultivated land was also performed. The sampling sites were randomly
selected in the cultivated land in the Midnapore district, which is the largest district in West Bengal. The phosphate fertilizer
is widely used for large agricultural production, mainly potatoes. The alpha activities have been measured using solid-state
nuclear track detectors (SSNTD), a very sensitive detector for alpha particles. The results show that alpha activity of those
fertilizer and soil samples varies from 141 Bq/kg to 2,589 Bq/kg and from 109 Bq/kg to 660 Bq/kg, respectively. These results
were used to estimate environmental radiation exposure on human health contributed by the direct application of fertilizers. 相似文献
20.
Patra AC Sumesh CG Mohapatra S Sahoo SK Tripathi RM Puranik VD 《Journal of environmental management》2011,92(3):919-925
A semi-dynamic leaching test was carried out for metallurgical wastes and ore samples from the uranium and copper mining industry over a 142 day period using distilled water and 0.1N NaNO(3) as solvents. Laser fluorimetry was used as the analytical technique to determine the total uranium content in the leachates. The cumulative leach fraction (CLF) of uranium release from the samples was calculated to be 0.22, 0.22, 0.07 and 0.39% for rock, uranium tailings, copper kinker ash samples and copper tailings respectively using distilled water as solvent and 0.31, 0.27, 0.05 and 0.59% for the same matrices using 0.1N NaNO(3). The release of mobile uranium fraction was very slow, being faster in the initial stage and then attained a near steady state condition. The diffusion coefficient and bulk release of uranium from the samples have been calculated. The processes governing the release of uranium from these matrices have been identified to be surface wash-off and diffusion. Hence the use of weak solvents (leach out the mobile/exchangeable fraction of uranium) under semi-dynamic conditions aids the determination of leaching parameters and identification of the leaching mechanism for mobile uranium fraction from different matrices by slow leaching processes. 相似文献