This work concerns the application of waste filler, consisting of scrap iron powder as received from machining in a small-scale workshop, in a self-produced thermoplastic starch (TPS) based on corn starch, acidified with acetic acid and plasticized with glycerol. The films obtained had a target thickness of 250 microns. The maximum amount of waste introduced was 0.8% and the material was produced on different supports, consisting either of a glass plate or of a silicone mould.
Tensile testing was performed and the best performance was obtained by the one prepared on glass support, although in general terms it was very far from similar industrial material, not exceeding a 10% maximum strain and being very sensitive to the disposition and geometry of the waste introduced. The value of the work is in the use of waste, which is rarely re-used, and in the possible production of conductive and magnetic biopolymer films.
The chemical formulae Ni1-xZnxGa0.5Fe1.5O4 (x= 0, 0.5, and 1) with spinel structure was prepared by a solid-state reaction at 1200 oC. The effect of irradiation by thermal neutrons is discussed on the structure by X-ray diffraction and by the Fourier transforms infrared absorption. After irradiation, the unit cell of the sample NZGF1 is expended, but for the samples NZGF2 and NZGF3 the unit cell is compressed. The cation distribution for all samples has been estimated according to the theoretical lattice parameters before and after irradiated. The spectra of FTIR show two bands, the band ν1 (611–563 cm−1) shifted to lower whereas the band ν2 (428–435 cm−1) shifted to increases. The vibrating sample magnetometer (VSM) was measured before and after irradiation. The results of magnetic properties show a decrease in introducing Zn ions and by irradiation. It can be concluded that these compositions are convenient as a radiation detector materials.
This study focused on the effects of materials management on the performance of SMEs in Kogi State. For this study, the method used was research survey design. The population of the study comprised of the SMEs in food processing and manufacturing industries in the Eastern Senatorial District of Kogi State. A multi-stage sampling was used to select 384 SME owners in Kogi State. Descriptive statistics, Multiple Regression and Ordered Probit Regression were used for analysis. Findings show that material planning and over-stocking of materials have significantly positive effects on profitability of SMEs in Kogi State; while under-Stocking of materials have significantly negative effect on profitability of SMEs in Kogi State. Finding further shows that persistent material under-stocking significantly causes customer’s satisfaction of SMEs in Kogi State to decrease. The study concluded that materials management is critical to the achievement of desired performance of SMEs. It was recommended that SME owners should engage in effective material planning and keep over-stocking of materials moderate. The implication of this is that profitability and customer’s satisfaction of SMEs in Kogi State will be enhanced if materials are properly managed.
The engineering of bandgap in materials is desired to develop new optoelectronic and photonic devices. The structure, electronic and optical properties of MgO (an insulator) mixed with CdO (a semiconductor) in the stoichiometry (0) are calculated using the ab initio density functional theory. The bond character changes from partial covalent to a more stronger covalent bond as Cd concentration increases in MgO. The dominant covalent bond, coupled with high bulk modulus values predicts that the mixed compounds are hard materials and that Cd and Mg compliments each other to increase the hardness. All the mixed compounds are indirect bandgap materials. The dielectric function and the refractive index shifts to lower energy domain as Cd concentration increases, indicating that the optoelectronic property of the compounds is Cd dependent. The evaluated optoelectronic property predicts the material to be effective for applications in the visible and UV regions of the energy spectrum.
Investigation of the thermal stability of epoxy and unsaturated polyester filled with some agricultural waste of Dates palm (Phoenix dactylifera) and African elemi (Canarium shweinfurthii) pits particulate composites has been conducted at a heating rate of 10°C/min using thermogravimetric analysis (TGA). The study showed that the composites can withstand temperature up to 340°C in inert atmosphere before decomposition and thus had good thermal stability as increased in temperature had little effect on the composites before the onset of degradation. The results show that the composites prepared from both fillers showed high thermal stability because onset of degradation of date palm pits/epoxy (DTP/EP) commenced at about 340°C which was unusual for lignocellulosic material while atili pits/ unsaturated polyester (ATP/UP) was 320°C. Literatures have shown that most lignocellulosic filler degrades at their processing temperature below 250°C. Thus, both fillers could be used in engineering plastics.