Computer Aided Grain Aeration Management: an Antidote to Grain Deterioration in Metal Silo

Aeration is very important for good grain storage as it helps to maintain uniform grain temperatures, minimizes moisture migration, and prevents quality loss of stored grain. The temperature of grain stock was monitored with the aid of temperature sensors installed inside the silo bins. Each silo contained twenty sensors located on five probes at different sections of the silo bin. Grain was received to experimented metal silos at 300C. The parameters for grain before reception were 1% broken grain, 1% mould, 1%  foreign matters, 68- 75KG/HL weight and 12% moisture content. Grain temperature rose to 450C within three weeks of storage. Temperature readings were taken in the morning and at evening times. Aeration system (fans) was operated several times, each time for long hours (≥5hours) enough to equalize temperature throughout the entire grain mass. Aeration fans were used to rapidly cool grain to 250C and then held it between 25 - 410C for over a year. The power requirement increased as air flow rate and grain depth increased. Aeration fans were controlled automatically from the operating control room while dehumidifiers were installed on the aeration fans. Loss recorded at manually operated metal silo was compared with the one from the silo monitored with computer software developed. While aeration could be used to lower grain temperature, minor changes took place on the moisture content of the grain mass. Loss was reduced to < 1% as against 5%. Aeration can be better monitored economically with the use of a computer system

Development of a Permeable Meter for Mould Industries Using Locally Sourced Materials

One of the major factors for production of quality casting is the control of properties of moulds and cores to make them uniform and consistent quality. Permeable meter is used for the determination of the venting ability of sand moulds and cores. This testing equipment is being imported to the country as at today. The cost is high, and they are not readily available to foundry operators.Hence there is need to design and develop a permeable meter using locally sourced materials and make it available at an affordable price, thereby improving foundry technology in Nigeria. Two different method could be used to measure permeability of sand; determination of air flow rate and measurement of pressure difference between the orifice and the top of sand specimen. The first method was adopted in the development of the Permeable meter. On testing, the values of permeability measured using the equipment was comparable to the results obtained from thestandardized imported one. The cost of production was 30% of the cost of imported one, not even now that exchange rate to international currency has skyrocketed. The work has incorporated design and fabrication principles that resulted in a relatively cheap product that can be constructed locally by an average Fabricator and Technicia

Review of passivity and electrochemical properties of nanostructured stainless steels obtained by surface mechanical attrition treatment (SMAT):trend and progress

Surface nanocrystallization provides the opportunity to produce gradient-structured metallic materials with improved properties. Several attempts have been made to produce nanostructured stainless steel (SS), along with the study of the resultant corrosion resistance. However, the current knowledge is insufficient to address the corrosion mechanism and the possible ways of enhancing the corrosion resistance after surface treatment. The present work reviews the past significant works on the effect of surface treatment by surface mechanical attrition treatment (SMAT) method as well as its processing parameters on the corrosion properties of SS. The corrosion resistance of nanostructured SS is influenced by the extent of grain refinement, compactness, and homogeneity of the passive film, Cr content, grain boundary structure, composition, and alloying elements. In addition, the resulting corrosion properties can be controlled by choosing the right processing parameters during treatment. Progress on the corrosion behavior of nanostructured steels was summarized and new avenues for further research and developments are proposed

Review of passivity and electrochemical properties of nanostructured stainless steels obtained by surface mechanical attrition treatment (SMAT):trend and progress

Surface nanocrystallization provides the opportunity to produce gradient-structured metallic materials with improved properties. Several attempts have been made to produce nanostructured stainless steel (SS), along with the study of the resultant corrosion resistance. However, the current knowledge is insufficient to address the corrosion mechanism and the possible ways of enhancing the corrosion resistance after surface treatment. The present work reviews the past significant works on the effect of surface treatment by surface mechanical attrition treatment (SMAT) method as well as its processing parameters on the corrosion properties of SS. The corrosion resistance of nanostructured SS is influenced by the extent of grain refinement, compactness, and homogeneity of the passive film, Cr content, grain boundary structure, composition, and alloying elements. In addition, the resulting corrosion properties can be controlled by choosing the right processing parameters during treatment. Progress on the corrosion behavior of nanostructured steels was summarized and new avenues for further research and developments are proposed

Optimization of Flexural Strength of Recycled Polyethylene-terephthalate (PET) Eco-Composite using Response Surface Methodology

Recycling and reuse of plastic waste by blending with virgin polymer has been affirmed to be the best way of managing the waste. Equally, agro-waste are best recycled than being burnt off. In the development of stronger and cheaper ecoefficient recycled PET composite for food packaging, this study focused on reinforcement of the blend of 20 wt. % recycled PET (rPET) and 80 wt. % virgin PET (vPET) with snail shell particulate and kenaf fiber via compression moulding process. The process parameters are fiber dosage, particulate dosage, moulding pressure and temperature. Box-Behnken design was engaged in the design of experiment and the samples were produced according to the experimental runs. Result of analysis of variance pinpointed the process factors as significant contributors to the flexural strength response. The model developed was validated to be significant and statistically fit. Interactions between the process variables as revealed by the response surface plots indicated the response was dependent on the interactive pattern between the variables. Response surface optimization showed an optimum flexural strength of 57.16 MPa was attainable at process parameters of 27.27 wt. %, 4.18 wt. %, 3.95 MPa, and 160 ˚C for fiber proportion, particulate proportion, moulding pressure and temperature respectively yielding 34.2 % improvement over the reference 80/20-vPET/rPET matrix. Model validation experiment undergone with the combined parameters and deviation of +0.036 was noted. Since the deviation is insignificant, the model is concluded to be statistically fit for predicting the flexural strength of the developed eco-composite

A review on the corrosion fatigue strength of surface-modified stainless steels

Materials are often exposed to simultaneous actions of corrosive environment and repeated stress, which sometimes leads to a significant decrease in corrosion fatigue strength. Several attempts have been made in the past to investigate the fatigue cracks initiation and propagation process across different materials. However, the current knowledge is insufficient to address the combined response of corrosion reaction and repeated stress on the fatigue properties of stainless steels (SS) especially when they are subjected to surface treatments. The present paper reviews the relevant past work done to date on the fatigue and corrosion fatigue strengths of nanostructured SS. The corrosion fatigue strengths of SS can be improved by the combined effects of surface treatments and the associated compressive residual stresses. The corrosion fatigue mechanism reviewed in this paper explains in detail the major factors involved in predicting the fatigue life behaviour including residual stress, loading frequency, microstructures, work-hardening, surface topography, surface treatment processing parameters, and fracture surface. For future works, the factors that could improve the corrosion fatigue behaviour of nanostructured SS were also discussed in detail

A review on the corrosion fatigue strength of surface-modified stainless steels

Materials are often exposed to simultaneous actions of corrosive environment and repeated stress, which sometimes leads to a significant decrease in corrosion fatigue strength. Several attempts have been made in the past to investigate the fatigue cracks initiation and propagation process across different materials. However, the current knowledge is insufficient to address the combined response of corrosion reaction and repeated stress on the fatigue properties of stainless steels (SS) especially when they are subjected to surface treatments. The present paper reviews the relevant past work done to date on the fatigue and corrosion fatigue strengths of nanostructured SS. The corrosion fatigue strengths of SS can be improved by the combined effects of surface treatments and the associated compressive residual stresses. The corrosion fatigue mechanism reviewed in this paper explains in detail the major factors involved in predicting the fatigue life behaviour including residual stress, loading frequency, microstructures, work-hardening, surface topography, surface treatment processing parameters, and fracture surface. For future works, the factors that could improve the corrosion fatigue behaviour of nanostructured SS were also discussed in detail