Potentials of date-seed/snail shells as a carburizer for enhanced mechanical properties of mild-steel

The suitability of date-seed/snail shells as a carburizer for enhanced mechanical properties of mild-steel using the packed carburization technique was investigated in this work. Standard tensile, impact and hardness test samples prepared from mild-steel were subjected to pack-carburization process using mixtures of date-seed and snail shell in the ratio 60:40 respectively at 800, 900, and 1 000 °C for 3 hours. The carburized samples were quenched in water at room temperature and further tempered at 300 °C for 30 minutes for residual stress relief of the quenching effect. The mechanical properties and optical microstructure of carburized specimen were performed. Results indicated an enhanced mechanical property of the carburized mild-steel using date-steel/snail shell as a carburizer compared to un-carburized same steel material. The tensile strength and hardness increased with increasing carburizing temperature, though with an associated decrease in ductility. The peak hardness (32.82 HRB) and tensile strength (521 MPa) with equivalent 31.28 and 51.45 percentage increments respectively were obtained at carburizing temperature of 1 000 °C. Hence, using date-seed/snail shell powder as a carburizer can enhance the mechanical properties of mild-steel

Optimization of fuel briquette made from bi-composite biomass for domestic heating applications

This study aimed at optimizing the fuel briquettes produced from flamboyant pod (FBP), and corn cob (CC) mixed with cassava starch (SB) as a binder using custom design methodology (CDM). The compressive strength, ash yield, and emission analysis of the briquettes produced were determined. The combustion efficiency parameters as well as CO, NO2, PM2.5, and PM10 of the emissions were compared to optimal fuel briquettes and charcoal fuel. The optimal combination of compressive strength and ash yield was obtained for the briquette fuel blend formulated from 30 wt.% flamboyant pod, 51 wt.% corn cob and 17 wt.% starch. While the water boiling time of the fuel increased by about 35–48% compared to charcoal fuel, the ignition time and the specific fuel consumption rate decreased by ∼34% and 16%, respectively. Furthermore, the major air pollutants were reduced from 222 to 196 ppm for CO, 3.63–2.34 ppm for NO2, and 0.21–0.09 ppm for PM 2.5. These properties of the briquette align with charcoal, thus supporting the use of flamboyant-corcob-starch (FBCS) briquettes as a supplementary source of energy to charcoal

Improving the in vitro Degradation, Mechanical and Biological Properties of AZ91-3Ca Mg Alloy via Hydrothermal Calcium Phosphate Coatings

For many years, calcium phosphate coatings to tailor the degradation behavior of magnesium and magnesium-based alloys for orthopaedic applications have received lots of research attention. However, prolong degradation behavior, its effect on biological and mechanical properties as well as osteoblastic response to single-step hydrothermally deposited calcium phosphate coatings remain poorly documented. In this study, Alamar blue assay, cell attachment, live/dead assay, and qRT-PCR were done to study the biological response of the coatings. Furthermore, immersion testing in SBF for 28 days and compression testing of the degraded samples were carried out to examine the degradation behavior and its effect on mechanical properties. The results indicated that coatings have a significant influence on both the substrate performance and structural integrity of coated AZ91-3Ca alloy. Immersion test revealed that coating deposited at pH 7, 100°C (CP7100) improves the hydrogen evolution rate by 65% and the degradation rate by 60%. As the degradation performance of coated samples improves so does the mechanical strength. CP7100 samples successfully retained 90% of their compressive strength after 14 days of immersion while bare AZ91-3Ca alloy lost its mechanical integrity. Furthermore, biological studies show that cells are happily proliferating, differentiating, and adhering to the coating surfaces, which indicates, improved osteointegration and osteogenesis with no sign of alkaline poisoning. qRT-PCR results showed that calcium phosphate coatings enhanced the mRNA levels for RUNX2, Col1A, and ALP that may exhibit a speedy bone recovery. Thus, calcium phosphate coatings produced via a single-step hydrothermal method improve the degradation behavior, mechanical integrity and stimulate the differentiation of osteoblast lining. This leads toward faster bone regeneration, which shows a great potential of these coatings to be used on degradable implants as a bioactive protective layer