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71.
Jyothunaik Ramavathu Thirupathi Reddy Kota 《International Journal of Sustainable Engineering》2020,13(3):204-217
ABSTRACT Analysis of plastic oil obtained from waste plastic through pyrolysis process, as an alternative to biodiesel is presented in this paper. The HCCI engine is considered for experimental validation of combustion performance and emission characteristics. To accumulate pyrolysis oil as fuel, the design modifications were made in external mixture formation on the existing computerised 4-stroke, single cylinder, water cooled, direct injection kirloskar diesel engine connected with eddy current dynamometer to satisfy HCCI conditions. HCCI engine can be worked on wide assortment of fuels beginning from diesel to different blends (WPPO 5%,10%,15% and 20% by volume) of biodiesel .The designed additional device connected to the engine is utilised for fuel vaporisation and mixture arrangement. In the experimental study, the combustion results were initiate to be of 39.69 % higher Rate of Heat Release (RoHR) for biodiesel HCCI as compared with diesel HCCI. Higher brake thermal efficiency (BTE) was found 37 % without exhaust gas recirculation (EGR) at WPPO 20 % biodiesel blend. And also found 50 % and 65 % reduction in NOx emission and 18 % and 28 % reduction in smoke opacity are obtained for biodiesel vapour induction without EGR and biodiesel vapour induction with 15 % EGR as compared with diesel fuel. The CO (0.34 %), and UHC (2.15 %) emissions are increases with 15 % EGR, but the emissions are within the standard limits specified by the emissions standards. 相似文献
72.
Examining Hazard Mitigation Within the Context of Public Goods 总被引:1,自引:0,他引:1
Reddy SD 《Environmental management》2000,25(2):129-141
/ This paper presents a case study of an American barrier island devastated by a hurricane to show how it is addressing the free-riding problem and protecting its public goods, thereby contributing to hazard mitigation. It examines hazard mitigation and the free-riding problem within the public goods framework. Free-riding is a term used in the public choice theory and common pool resource literature. It is a term used for describing the actions of rational individuals who freely exploit a collective or public good at the expense of others. Free-riding is a major problem faced by public goods. The problem very frequently occurs in the context of hazard mitigation and coastal resource management. Very little is known about the factors that contribute to the promotion of hazard mitigation. This paper identifies some of the important factors that help local institutions provide and sustain hazard mitigation measures. Theoretical and practical implications for hazards research and disaster management policy are presented. 相似文献
73.
Reddy MS Basha S Joshi HV Sravan Kumar VG Jha B Ghosh PK 《Waste management (New York, N.Y.)》2005,25(7):747-754
Alang-Sosiya is the largest ship-scrapping yard in the world, established in 1982. Every year an average of 171 ships having a mean weight of 2.10 x 10(6)(+/-7.82 x 10(5)) of light dead weight tonnage (LDT) being scrapped. Apart from scrapped metals, this yard generates a massive amount of combustible solid waste in the form of waste wood, plastic, insulation material, paper, glass wool, thermocol pieces (polyurethane foam material), sponge, oiled rope, cotton waste, rubber, etc. In this study multiple regression analysis was used to develop predictive models for energy content of combustible ship-scrapping solid wastes. The scope of work comprised qualitative and quantitative estimation of solid waste samples and performing a sequential selection procedure for isolating variables. Three regression models were developed to correlate the energy content (net calorific values (LHV)) with variables derived from material composition, proximate and ultimate analyses. The performance of these models for this particular waste complies well with the equations developed by other researchers (Dulong, Steuer, Scheurer-Kestner and Bento's) for estimating energy content of municipal solid waste. 相似文献
74.
Exposure of the freshwater field crab Barytelphusa guerini to a sublethal concentration of NaF (30 mg litre(-1)) caused significant alterations in protein metabolism. After an exposure time of 15 days, the crab was found to have a marked depletion of total protein and free amino acid content. A significant elevation in transaminases, Aspartate aminotransferase (AAT) and Alanine aminotransferase (ALAT), and Glutamate dehydrogenase (GDH) activities was reflected in the free amino acid levels of the tissues. 相似文献
75.
Pant HK Nair VD Reddy KR Graetz DA Villapando RR 《Journal of environmental quality》2002,31(4):1399-1405
Agricultural lands are often used for constructing stormwater treatment areas (STAs) to abate nutrient loading to adjacent aquatic systems. Flooding agricultural lands to create STAs could stimulate a significant release of phosphorus (P) from soil to the water column. To assess the suitability of agricultural lands, specifically those impacted by animal operations, for the construction of STAs, soils from different components of the New Palm-Newcomer dairies (Nubbin Slough Basin, Okeechobee, Florida, USA) were collected by horizon and their P retention and release capacities estimated. In general, P released from A-horizon soil under flooded (anaerobic) conditions was greater than under drained (aerobic) conditions due to redox effect on iron (Fe) and consequent P releases. However, the P released from Bh-horizon soil was greater under aerobic conditions than under anaerobic conditions, possibly due to excessive aluminum (Al) content in the horizon. Double acid-extractable calcium (Ca), magnesium (Mg), Al, and P explained 87% of the variability in P release under aerobic conditions, and 80% of that under anaerobic conditions. The P release maxima indicated a high solubility of P in A-horizon soil from both active and abandoned dairies (13 and 8% of the total P, respectively), suggesting that these soils could function as potential sources of P to the overlying water column when used in STA construction. Preestablishment of vegetative communities or chemical amendment, however, could ameliorate high P flux from soil to the water column. 相似文献
76.
Accretion of organic matter in wetlands provides long-term storage for nutrients and other contaminants. Water-table fluctuations and resulting alternate flooded and drained conditions may substantially alter the stability of stored materials including phosphorus (P). To study the effects of hydrologic fluctuation on P mobilization in wetlands, recently accreted detrial material (derived primarily from Typha spp.) was collected from the Everglades Nutrient Removal Project (ENRP), a constructed wetland used to treat agricultural drainage water in the northern Everglades. The detrital material was subjected to different periods of drawdown and consecutive reflooding under laboratory conditions. The 31P nuclear magnetic resonance (31P NMR) spectroscopy analysis revealed that sugar phosphate, glycerophosphate, polynucleotides, and phospholipids (glycerophosphoethanolamine and glycerophosphocholine) were the major forms of P in the detrital material. After 30 d of drawdown, polynucleotides were reduced to trace levels, whereas sugar phosphate, glycerophosphate, and phospholipids remained the major fractions of organic P. Microorganisms seemed to preferentially utilize nucleic acid P, perhaps to obtain associated nutrients including carbon and nitrogen. At the end of the 30-d reflooding period, cumulative P flux from detritus to water column accounted for 3% of the total P (< or = 15 d of drawdown) and further decreased to 2% at 30 d of drawdown, but increased to 8% at 60 d of drawdown. The drawdown (< or = 30 d) not only reduced P flux to the water column, but also increased the humification and microbial immobilization of P. Excessive drawdown (60 d), however, triggered the release of P into the water column as the water content of detritus decreased from 95 to 11%. 相似文献
77.
Babu MS Gopal NV Reddy KP 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(1):21-27
This study reports the effects of low level developmental Pb exposure on specific brain regions like hippocampus, cerebellum and cerebral hemispheres of antioxidant enzyme activities. Wistar dams were exposed to 50 ppm, 100 ppm and 500 ppm of Pb acetate in drinking water during pregnancy and lactation (gestation day 6 through PND 21 (post natal day) and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione reductase (GR) were determined in the hippocampus, cerebellum and cerebral hemispheres of pups during treatment period (PND 7, 14, and 21 days) and also during withdrawl period (PND 35, 45, 60 and 90 days). During treatment period, SOD activity significantly (p < 0.05) decreased in all regions of all the treated groups with maximum decrease in 500 ppm treated group of 21 days, while GSH-Px and GR activities increased with maximum increase in 21 days aged 500 ppm group. During withdrawl period, the activities of all enzymes were significantly (p < 0.05) reversed. Thus the perinatal exposure of dams to variable dosages of low level lead results in characteristic neurochemical alterations in rat brain regions due to impaired antioxidants function. 相似文献
78.
A pentachlorophenol (PCP) mineralizing bacterium was isolated from the secondary sludge of pulp and paper mill and identified
as Pseudomonas stutzeri strain CL7. This isolate used PCP as its sole source of carbon and energy and was capable of degrading this
compound as indicated by stoichiometric release of chloride and biomass formation. P. stutzeri (CL7) was able to mineralize a high
concentration of PCP (600 mg/L) than any previously reported Pseudomonad with PCP as sole carbon source. As the concentration
of PCP increased from 50 to 600 mg/L, the reduction in the cell growth was observed and the PCP degradation was more than 90%
in all studied concentrations. This isolate was able to remove 66.8% of PCP from the secondary sludge of pulp and paper mill when
supplemented with 100 mg/L of PCP and grown for two weeks. This study showed that the removal e ciency of PCP by CL7 was
found to be very e ective and can be used in PCP remediation of pulp paper mill waste in the environment. 相似文献
79.
Dongkai Xu Rajiv Malhotra N. Venkata Reddy Jun Chen Jian Cao 《Journal of Manufacturing Processes》2012,14(4):487-494
Single point incremental forming (SPIF) is a new sheet metal forming process characterized by higher formability, product independent tooling and greater process flexibility. The inability of conventional single pass SPIF to form vertical walls without failure is overcome by forming multiple intermediate shapes before forming the final component, i.e., multi-pass single point incremental forming (MSPIF). A major issue with MSPIF is significant geometric inaccuracy of the formed component, due to the generation of stepped features on the base. This work proposes analytical formulations that are shown to accurately and quantitatively predict the stepped feature formation in MSPIF. Additionally, a relationship is derived among the material constants used in these analytical equations, the yield stress and thickness of the blank material, such that the computational effort required for the calibration of these constants can be minimized. Finally, the physical effects of yield stress and sheet thickness on the rigid body translation are further discussed. 相似文献
80.
Ramachandra Jayashree Tenkila Veerappa Subba Reddy Nandanavana Udupi Dinesh Acharya 《Environmental science and pollution research international》2022,29(28):41953-41970
Environmental Science and Pollution Research - Accurate estimation of reference evapotranspiration (ET0) is an essential requirement for water resource management and scheduling agricultural... 相似文献