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"A range of microstructure as a result of low-temperature crystallization of amorphous alloy based on the composition Fe68Cr18Mo2B12 prepared by chill block melt spinning casting has been investigated using x-ray diffractometer and transmission electron microscope. Low-temperature crustallization of the amorphous alloy produced a very fine microstructure consisting of Fe; body centered tetragonal Fe3B and a small proportion of orthorhombic Fe3B. The body centered tetragonal Fe3B was found to contain fine and coarse faults with lead to streaking in selected area diffraction patterns. The crystallization of the present material is proposed to occur by primary crystallization of solid solution ferritic phase followed by a eutectic reaction of Fe+Fe3B."

"The conventional method of generating energy is by means of combustion puts significant pressure on the environment. Therefore the study of gasification is needed. Low temperature gasification produces synthetic gas as a fuel or material to produce chemicals in industry. This study investigated the gasification characteristics of Victorian brown in terms of reaction competion and structural changes happen. It was found that as the concentration of oxygen reaches 5% and 6 second residence time, char yield goes to as low as 45 % to 25 %. , the char yield decreases, which indicates more synthetic gas was produced in the reaction. The structural changes of char during gasification were also observed, results shows the reaction mechanism of char as it goes through gasification. This is illustrated by the BET surface area, pore volume and also the pore size. In CO2 dominated reaction, the surface area goes as high as 240 m2/g to 180 m2/g due to char fragmentation and promptly decrease to around 170 m2/g, while in O2 reaction the surface area dropped to around 160 m2/g. SEM analysis shows considerable increase in the frequency of char particles which diameter smaller than 120 microns ( from 0.27 to 0.36 for particle smaller than 100 microns and from 0.28 to 0.35 for particle at 100 to 120 microns). While there is a noticeable decrease in the frequency of larger particle (0.26 to 0.19 for 120 to 140 microns, 0.09 to 0.06 for 140 to 160 microns and 0.1 to 0.03 for larger than 160 microns)."

"An investigation to structural and wear behaviour of nitrided AISI 316 L stainless steel resulting from low temperature fluidized bed nitriding has been made in the present work It was found that the wear resistance of nitrided specimens was related to the formation of a preetpitation-free hardened layer on the austenitic surface. In the present laboratory experiments, the precipitation-free or S phase layer with a surface hardness of ~1350 H Va 5 was produced at a nitriding condition of 450'C for 6h. The formation of this S phase layer significantly improved wear resistance of the stainless steel. Wear track observation by SEM revealed that the specimens without formation of S phase layer produced heavy scars due to tearing and local plastic deformation. The present work also suggests that fluidized bed heat treatment furnace can be utilised for nitriding the austenitic stainless steels at low temperatures below 5 00 ?C to produce S' phase nitrdid layer without losing the stainless feature of this material."

"In this study, modeling of the crossing point temperature (CPT) phenomenon in the low-temperature oxidation of coal was carried out using COMSOL Multiphysics®. Low-temperature oxidation can lead to spontaneous combustion of coal stockpiles. The CPT phenomenon was modeled with the kinetics data obtained from a prior laboratory experimental study. The coupling of the heat-transfer phenomenon through conduction and convection determined the thermal evolution model. In this case, coal received the initial heat of the oven temperature increases. As the coal temperature rose, the heat generated from oxidation was released into the environment via conduction and convection. Meanwhile, oxidation products and oxygen were transferred by convection and diffusion. The effects of moisture and the humidity were not considered. The outcomes of modeling were validated through comparison with the results of experimental tests, and the modeling result agreed well with the experiment tests, with temperature deviations of about 0.9%. The effects of airflow rate, oxygen concentration, porosity, and the initial temperature on low-temperature coal oxidation were also examined."

"In this study, modeling of the crossing point temperature (CPT) phenomenon in the low-temperature oxidation of coal was carried out using COMSOL Multiphysics®. Low-temperature oxidation can lead to spontaneous combustion of coal stockpiles. The CPT phenomenon was modeled with the kinetics data obtained from a prior laboratory experimental study. The coupling of the heat-transfer phenomenon through conduction and convection determined the thermal evolution model. In this case, coal received the initial heat of the oven temperature increases. As the coal temperature rose, the heat generated from oxidation was released into the environment via conduction and convection. Meanwhile, oxidation products and oxygen were transferred by convection and diffusion. The effects of moisture and the humidity were not considered. The outcomes of modeling were validated through comparison with the results of experimental tests, and the modeling result agreed well with the experiment tests, with temperature deviations of about 0.9%. The effects of airflow rate, oxygen concentration, porosity, and the initial temperature on low-temperature coal oxidation were also examined."