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The concentrations of minor and trace elements, including some of environmental significance, were determined in coals and ashes of Barapukuria thermal power plant in Bangladesh by a neutron activation analysis technique. Synchronized sampling of feed coal, fly ash, and bottom ash was undertaken over a limited time period. The ranges and arithmetic mean of the concentrations of 30 minor and trace elements in the coals and ashes are presented for the first time. Study of the enrichment factor relative to crustal abundances (Clarke values) indicates that Barapukuria coals are moderately enriched (2–6 times) with Sm, Dy, La, Ce, Th, Nd, W, Hf, Sb, and U. Distribution of the trace elements into fly ash and bottom ash after combustion in the power plant was also studied.

Microencapsulated paraffin, a novel solar storage material, was prepared by simple coacervation technique and its performance characteristics, when subjected to cyclic operation, were evaluated in terms of structure and particle profile using SEM and FTIR, and the energy storage and release capacity expressed by DSC. The microencapsulated paraffin has shown large energy storage and release capacity (56∼58 J/g) during its phase change, and maintains its energy storage and release capacity, chemical characteristics and structural profile even after one thousand thermal recycles.

Microencapsulated paraffin, a novel solar storage material, was prepared by complex coacervation technique and its performance was evaluated in terms 1of encapsulation ratio, hydrophilicity, energy storage capacity, and size distribution. The experiments were designed, based on surface response method, to optimise the processing conditions. The sizes of the microencapsulated paraffin particle were 50–100 μm. For an emulsification time of l0min and the addition of 6–8 ml (2.9−3.8% w/w) of formaldehyde (HCHO), the paraffin encapsulation ratio was found higher in different ratio of paraffin wax to coating (menu). It was also found that a higher coating to paraffin ratio leads to a higher paraffin encapsulation ratio. The hydrophilicity value of microencapsulated paraffin depended mainly on the ratio of paraffin to coating. The higher the ratio, the lower was its product hydrophilicity. In the same ratio of paraffin wax to coating, the higher concentration of HCHO led to a lower hydrophilicity of the product....

Liquid chromatographic techniques have been employed to evaluate the sorption and diffusion characteristics of smaller molecular size amino acids on large zeolite KX-type crystals. The three amino acids investigated in the present study were cysteine, threonine, and serine. All three amino acids adsorbed quite rapidly but there are significant differences in both the equilibrium constants and intracrystalline diffusivities. Combined with the kinetic and equilibrium data of the other three amino acids reported previously, it can be concluded that the larger molecules generally show a lower equilibrium constant. However, no obvious trend can be observed for intracrystalline diffusivity data.