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The present study investigates the effect of varying particle size and porosity on the heating behavior of a metallic particulate compact in a 2.45GHz multimode microwave furnace. Experiments on copper suggest that unlike monolithic (bulk) materials, metallic materials do couple with microwaves when they are in particulate form. The powder compacts having higher porosity and smaller particle sizes interact more effectively with microwaves and are heated more rapidly. A dynamic electromagnetic-thermal model was developed to simulate the temporal temperature distribution using a 2-D finite difference time domain (FDTD) approach. The model predicts the variation in temperature with time during heating of copper powder compacts. The simulated heating profiles correlate well with those observed from experiments

The melting of steel scrap in high temperature liquid iron melt is investigated by conducting cold model experiments of the melting of ice sample of different geometries and sizes in an argonstirred vessel containing water. The melting process of ice samples is observed using a highspeed camera. Design of experiments is based on similarity criteria. The relationships between non-dimensional groups related to heat transfer (Nu, Re, Pr, and Gr) are derived for different experimental conditions. The results are compared with those reported in the literature. The heat transfer coefficient is estimated as a function of mixing power and is found to be in good agreement with the calculated values obtained by using reported relationships in literature.

A thermodynamic (equilibrium) model is developed for the BOF process. The predictions of this model show the trend of reactions when the process is considered to be at thermodynamic equilibrium. In the case of a real process, however, some tuning and adaptation becomes necessary to make more accurate predictions. A dynamic model is developed in which the kinetics of scrap dissolution is also incorporated. A comparison of the results of the equilibrium and dynamic models (made with some tuning parameters) reveals that mixing is the prime factor which can alter the course of reaction at any particular instant. Mixing is greatly affected by oxygen flow rate, lance height and the nature of scrap. The understanding of the secrets of process dynamics becomes clearer with this approach, providing a good insight into the process.

The viscosities of the industrial basic oxygen furnace (BOF) slag with varying compositions of MgO, Al2O3, TiO2, and MnO were continuously measured at a temperature range between 1400 and 1700 °C using the rotating bob method. Three characteristic temperatures for the melting behavior of the BOF slag were investigated using a high-temperature microscope. The solid fraction of the slag was calculated by FactSage 7.2 using the FTOxid database. General observations from the experimental data show that the increase in MgO tends to increase viscosity. However, Al2O3, TiO2, and MnO decrease viscosity up to a certain level, and beyond that, they also increase the viscosity. The measured values of the viscosity of BOF slags were compared and discussed with known data from the literature. Finally, the activation energy of BOF slags with different compositions of MgO, Al2O3, TiO2, and MnO was calculated in the temperature range of industrial operations.

Deprotection O 0345 Superoxide Induced Deprotection of 1,3-Dithiolanes: A Convenient Method of Dedithioacetalization. -Tetraethylammonium superoxide, generated in situ by the phase-transfer reaction of KO2 and NEt4Br, brings about an easy deprotection of a variety of 1,3-dithiolanes (I) under significantly mild reaction conditions. -(SHUKLA, A. K.; VERMA, M.; SINGH*, K. N.; Indian J. Chem., Sect. B: Org.

The present study compares the temperature distribution within cylindrical samples heated in microwave furnace with those achieved in radiatively-heated (conventional) furnace. Using a two-dimensional finite difference approach the thermal profiles were simulated for cylinders of varying radii (0.65, 6.5, and 65 cm) and physical properties. The influence of susceptor-assisted microwave heating was also modeled for the same. The simulation results reveal differences in the heating behavior of samples in microwaves. The efficacy of microwave heating depends on the sample size and its thermal conductivity

The phosphorus partition between the unkilled liquid crude steel and the high basicity (CaO/SiO2 = 4.2), basic oxygen furnace (BOF) slags with varying compositions of Al2O3, TiO2, and MnO is studied at temperatures 1600 and 1650 °C. The tests are conducted in both “slag‐to‐metal” and “metal‐to‐slag” directions and for durations of 30 and 60 min. The measured results are compared with the values reported in literature and found to be in good agreement with some of them. It is found in the investigation of high‐basicity BOF slags, that Al2O3, MnO, and TiO2 lower the phosphorus partition. The phosphorus partition increases with increasing optical basicity. The phosphorus partition shows a maximum when the FeO content is in range of 25–30 mass%. The MgO content slightly increases the phosphorus partition.