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121.
Increased use of farm machinery along with other agricultural inputs has enhanced the production and productivity of Indian farms. Simultaneously, it has also increased occupational health hazards on the farms. Major occupational health hazards are farm related injuries. Very little information is available about the type and nature of agricultural injuries on Indian farms. In the present study, agriculture injuries data were collected for the period 1996–2000 for the Etawah district of Uttar Pradesh in India. It has a total population of 1.4 million while 0.75 million were associated with agricultural activities. The agricultural injuries incidence rate was 0.8 per thousand workers per year in the study area. Out of all agricultural injuries, 9% injuries were fatal. The highest number of injury victims were in the age group of 30–44 years. The highest percentages of injured victims were literate but non-matric. The monetary loss due to agricultural injuries in the study area was estimated to be about US $730,000 per year. To minimize agricultural injuries, development of interventions and trainings needs to be organized at block levels for proper and safe operation of agricultural equipment.  相似文献   
122.
Iron-carbon (Fe-C) composite microspheres prepared through a facile aerosol-based process are effective remediation agents for the simultaneous adsorption and reduction of chlorinated hydrocarbons. Complete dechlorination was achieved for the class of chlorinated ethenes that include tetrachloroethylene (PCE), trichloroethylene (TCE), cis- and trans-1,2-dicloroethylene (c-DCE, t-DCE), 1,1-dichloroethylene (1,1-DCE) and, vinyl chloride (VC). The Fe-C particles potentially provides multi-functionality with requisite characteristics of adsorption, reaction, and transport for the effective in situ remediation of chlorinated hydrocarbons. The carbon support immobilizes the ferromagnetic iron nanoparticles onto its surface, thereby inhibiting aggregation. The adsorptive nature of the carbon support prevents the release of toxic intermediates such as the dichloroethylenes and vinyl chloride. The adsorption of chlorinated ethenes on the Fe-C composites is higher (>80%) than that of humic acid (<35%) and comparable to adsorption on commercial activated carbons (>90%). The aerosol-based process is an efficient method to prepare adsorptive-reactive composite particles in the optimal size range for transport through the porous media and as effective targeted delivery agents for the in situ remediation of soil and groundwater contaminants.  相似文献   
123.
Gundi VA  Reddy BR 《Chemosphere》2006,62(3):396-403
The degradation of a widely used organophosphorus insecticide, monocrotophos (dimethyl (E)-1-methyl-2-methylcarbamoyl vinyl phosphate) in two Indian agricultural soils at two concentration levels, 10 and 100 microg g(-1) soil under aerobic conditions at 60% water-holding capacity at 28+/-4 degrees C was studied in a laboratory. The degradation of monocrotophos at both concentrations in black vertisol and red alfinsol soils was rapid accounting for 96-98% of the applied quantity and followed the first-order kinetics with rate constants (k) of 0.0753 and 0.0606 day(-1) and half-lives (t1/2) of 9.2 and 11.4 days, respectively. Degradation of monocrotophos in soils proceeded by hydrolysis with formation of N-methylacetoacetamide. Even three additions of monocrotophos at 10 microg g(-1) soil did not result in its enhanced degradation. However, there was cumulative accumulation of N-methylacetoacetamide in soils pretreated with monocrotophos to the tune of 7-15 microg g(-1) soil. Both biotic and abiotic factors were involved in degradation of monocrotophos in soils.  相似文献   
124.
125.
ABSTRACT: This study presents analytic and graphical techniques for estimation and optimization of kinematic wave parameters. Because the techniques are derived from the kinematic wave theory, the optimized parameter values will have minimum bias in them.  相似文献   
126.
ABSTRACT: Four methods of determining rainfall-excess are considered. They include Ø-index and equations of Horton, Kostyakov and Philip. These methods are utilized in a nonlinear kinematic wave model to predict surface runoff from two natural agricultural watersheds. The effect of determining rainfall-excess on surface runoff response is then examined. It is observed that errors in rainfall-excess constitute a major source of error in runoff prediction. The choice of a method of determining rainfall-excess is thus crucial to runoff computation.  相似文献   
127.
Abstract: The concern about water quality in inland water bodies such as lakes and reservoirs has been increasing. Owing to the complexity associated with field collection of water quality samples and subsequent laboratory analyses, scientists and researchers have employed remote sensing techniques for water quality information retrieval. Due to the limitations of linear regression methods, many researchers have employed the artificial neural network (ANN) technique to decorrelate satellite data in order to assess water quality. In this paper, we propose a method that establishes the output sensitivity toward changes in the individual input reflectance channels while modeling water quality from remote sensing data collected by Landsat thematic mapper (TM). From the sensitivity, a hypothesis about the importance of each band can be made and used as a guideline to select appropriate input variables (band combination) for ANN models based on the principle of parsimony for water quality retrieval. The approach is illustrated through a case study of Beaver Reservoir in Arkansas, USA. The results of the case study are highly promising and validate the input selection procedure outlined in this paper. The results indicate that this approach could significantly reduce the effort and computational time required to develop an ANN water quality model.  相似文献   
128.
ABSTRACT: The principle of maximum entropy (POME) was used to derive an alternative method for parameter estimation for the three parameter lognormal (TPLN) distribution. Six sets of annual peak discharge data were used to evaluate this method and compare it with the methods of moments and maximum likelihood estimation.  相似文献   
129.
Journal of Polymers and the Environment - The transition from fossil-based to bio-based materials requires in-depth environmental durability analysis for material engineering and construction...  相似文献   
130.
CO2 absorption by liquid-containing amines to form carbamate and bicarbonates is an effective method of CO2 mitigation from industrial exhausts, but this process is expensive and requires large quantities of amines. Here we modified chitosan, a naturally occurring biopolymer containing NH2 functions, to use it for CO2 absorption in aqueous media. Chitosan was dispersed in 40% aqueous NaOH solution then treated with monochloroacetic acid dissolved in isopropanol, to yield O-carboxymethylchitosan. Results show that the CO2 absorption capacity of O-carboxymethylchitosan is 0.508 g/g, which is higher than the capacity of conventional amines such as 1-aminoamine, 2-methylpropanolamine and methyldiethanol amine, but lower than the capacity of monoethanolamine. A cyclic study showed that O-carboxymethylchitosan is a stable component for CO2 absorption and regeneration.  相似文献   
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