930 research outputs found
Monte Carlo Simulation of temperature dependence of grain growth kinetics in C-Mn Steel prior to hot rolling
A Monte Carlo simulation framework has been proposed to characterize grain growth phenomena during microstructural evolution of plain C-Mn steel under reheating condition prior to hot rolling. The effect of deformation temperature on the temporal evolution of the grains has been analyzed during reheating operation prior to hot rolling
Monte Carlo simulation of microstructure evolution during thermo-mechanical rolling of steel using grid computing technology
A Monte Carlo (MC) simulation methodology
using high performance computing (HPC) has been
proposed to characterize grain growth kinetics and
recrystallisation phenomena during hot rolling of C-Mn
and TRIP steels. The simulation framework comprises of
mesoscale modelling of evolution of grain growth and
microstructure incorporating the system energetics of
grain boundary energy and stored energy which are
essentially the driving force for the evolution process. An
in-house MC computer code has been developed and
implemented in the GARUDA grid. This facilitated
achieving faster convergence of the MC algorithm for a
given lattice structure. The simulated grain growth and
microstructure evolution have been successfully validated
with the published data. It is inferred that the MC
simulation in conjunction with HPC grid capability can be
a powerful tool to simulate material behaviour at
mesoscopic scale during thermo-mechanical processing of
materials
Time evolution of spin state of radical ion pair in microwave field: An analytical solution
The paper reports an exact solution for the problem of spin evolution of
radical ion pair in static magnetic and resonant microwave field taking into
account Zeeman and hyperfine interactions and spin relaxation. The values of
parameters that provide one of the four possible types of solution are
analysed. It is demonstrated that in the absence of spin relaxation, besides
the zero field invariant an invariant at large amplitudes of the resonant
microwave field can be found. The two invariants open the possibility for
simple calculation of microwave pulses to control quantum state of the radical
pair. The effect of relaxation on the invariants is analysed and it is shown
that changes in the high field invariant are induced by phase relaxation.Comment: 18 pages, 7 figure
Data-Based Performance Modelling of Hydrocyclone for Processing Iron Ore Fines
In this study, a data driven performance characterization model of hydrocyclone has been developed using multiple experimental data set collected from the published literature pertaining to processing of iron ore fines. The cut size, d50, has been determined for a given cyclone operating conditions using Lagrangian interpolation technique. A reduced efficiency curve has been constructed to map the performance and the functional behaviour has been modeled employing three typical distribution functions, namely, Rosin-Rammler, Exponential and Logistic. All pertinent model parameters have been estimated in accordance with the experimental data sets. It has been observed that all these functions fairly mimic the performance of cyclone for processing iron ore in the particle size range 25-300 m. Rosin-Rammler distribution found to be a better function for fitting the experimental data set in comparison to Exponential and Logistic functions to characterize the performance
ENVIRONMENTAL ACCOUNTS: TIME SERIES + ECO-TAXES
This study was commissioned by the European Commission in cooperation with Eurostat with the
objective of improving and extending the scope of the environmental accounts for Ireland. It follows
two previous studies, Pilot Environmental Accounts published by the Central Statistics Office and the
Satellite Environmental Accounts for Ireland 1996, unpublished report to Eurostat (2000). As indicated
in the title, this study presents time series, which in some cases are of considerable length, and provides
information on what could loosely be called eco-taxes. Additionally, where feasible the study relates
environmental information to the underlying economic magnitudes and movements, and broadens the
information considerably.
The report consists of three self-contained sections. The sections cover (1) emissions to air, (2)
discharges to water and (3) disposals of solid waste and these three types of releases to the environment
are disaggregated according to NACE Rev 1 by five major economic sectors:
Agriculture/forestry/fishing
Energy transformation
Industry
Transport
Services
Households
though in some areas the breakdown is unavoidably less detailed and it is more detailed in others.
Section 1 on emissions to air concentrates on greenhouse gases and on improving the underlying
information on energy use. Behavioural analyses have been hampered in the past by inadequate time-series
of energy-related prices and taxes so that a large effort was devoted here to presenting coherent
time-series of these items
Effect of organic manures and microbial inoculants on yield, root colonization and total bacterial population in turmeric (Curcuma longa L.) intercropped in arecanut (Areca catechu L.) garden
The effect of combination of organic manures namely, compost, vermicompost, phosphocompost and mustard cake and microbial inoculants namely, Azospirillum brasilense and arbuscular mycorrhiza (Glomus fasciculatum) were evaluated for the organic production of turmeric (Curcuma longa) (cv. Suguna) grown as intercrop in arecanut (Areca catechu) (cv. Mohitnagar) plantation at Mondouri (Nadia, West Bengal) A significant difference in rhizome yield was noticed when organic manure-microbial inoculant combination was applied when compared with recommended dose of fertilizers (inorganic). Among different treatment combinations tried, the most effective treatment was vermicompost + Azospirillum sp. + Glomus sp. (28.94 t ha-1), followed by compost + Azospirillum sp. + Glomus sp. (26.93 t ha-1), as compared to recommended inorganic NPK (24.11 t ha-1). Maximum root colonisation (74%) with microbial inoculants at 180 days after planting was observed with vermicompost + Azospirillum sp. + Glomus sp. Maximum bacterial population (105.25 x 105 CFU g-1 soil) at harvest was noticed in compost + Azospirillum sp. + Glomus sp., as compared to lowest population with recommended NPK (56.35 x 105 CFU g-1 of soil).
 
Performance characterization of water-only Cyclone for processing high ash Indian coal
In this study semi-empirical performance models have been employed to characterize the
performance of water-only cyclone on the basis of experimental data modelling for fine coal cleaning.
Experiments have been conducted in the laboratory on a 100 mm water only cyclone. High ash coals
used for the experiments belong to the Patherdih and Munidih colliery in the Eastern part of India.
Separation based on specific gravity was studied on Patherdih sample whereas size classification
analysis has been carried out on Munidih sample. Washability studies on Patherdih sample have been
undertaken to determine the specific gravity of effective separation for a desired coal quality. The Mayer
curve has been employed to plot float-and-sink analysis from which the Tromp distribution curve is
constructed. A reduced efficiency curve has been generated based on specific gravity as well as size
classification analysis. Attempts have been made to describe the reduced efficiency curve by employing
Rosin-Rammler and Logistic distribution function to characterize the performance of the cyclone. A
simplified approach has been proposed to estimate the performance model parameters. Experiments
were conducted by varying the operating parameters like spigot diameter, feed inlet pressure and
percentage solids in the feed to study the sensitivity of operating conditions. The effect of operating
variables on the performance of the cyclone in terms of classification function has been investigated. A
graphical user interface (GUI) based user friendly software (HYDROSIM) has been developed based on
semi-empirical models for calculating the cut-size (d50) under various operating conditions
Modelling performance of water-only cyclone as a gravity separator for fine coal cleaning
The performance of a gravity separator treating coal is characterized by plotting a Tromp distribution curve. In this study semi-empirical performance models have been employed to characterize the performance of water-only cyclone on the basis of experimental data modelling for fine coal cleaning. Experiments have been conducted in the laboratory on a 100 mm water only cyclone. Raw coal used for the experiments belong to Patherdih colliery in the Eastern part of India. Washability studies have been undertaken to determine the gravity separation for a desired coal quality. The Mayer curve has been employed to plot float-and-sink analysis from which the Tromp distribution curve has been constructed. A reduced efficiency curve has been obtained and attempts have been made to describe the behaviour using a Rosin-Rarnmler type distribution function characterizing the performance of the cyclone. A simplified approach has been purposed to estimate the model parameters
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