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Rice husk is usually generated as waste in large quantities but yet to be optimally utilized. Due to the pollution effects associated with poor approach prevalently adopted for its disposal, valorizing it into economical and sustainable material for building construction is a necessary option to provide solution for future generation. In this research, separate dry mortars were prepared using cement grades 32.5R and 42.5N and the influence of rice husk ash (RHA) inclusion on their electrical characteristics was investigated. The materials used were batched by volume and the RHA was utilized as a partial substitute for cement at 10 % level. All the samples were cured for 21 days and then allowed to dry completely prior to the tests implementation. The results showed decrease in electrical resistance with temperature (ranging from 20oC to 50oC) due to incorporation of the RHA. Though samples with the RHA content possessed ability to act as smart mortars for temperature monitoring/sensing, utilization of cement grade 42.5N ensured a better performance. By utilizing rice husks in such undertakings, their associated disposal problems could be tackled and construction of inexpensive but sustainable building with large temperature sensing capability could be enhanced.

The use of Schering Bridge arrangement in combination with function generator and oscilloscope allows for precise measurement of heat dissipation in plant materials. This study aims to determine and compare the heat dissipation properties of young bitter leaf (YBL) and mature bitter leaf (MBL) samples obtained from two different locations. Measurements were conducted on ten fresh leaf samples per category from each location. Results indicated that for samples from the first location, the dissipation factors for YBL and MBL were (2.076 ± 0.010) and (3.231 ± 0.013) respectively, while from the second location, the values were (3.231 ± 0.013) and (3.233 ± 0.015) respectively. The data suggest that while the geographical location does not significantly influence the heat dissipation of bitter leaf (Vernonia amygdalina), the age of the leaves does, with YBL exhibiting a higher capacity to withstand elevated temperatures compared to MBL under identical storage conditions. This study provides insight into the thermal properties of bitter leaf, contributing to broader research on plant thermoregulation. The novelty of this work lies in its demonstration that leaf age, rather than location, is a determinant factor in heat dissipation. [ABSTRACT FROM AUTHOR]

In Nigeria, sawdust is continuously generated in large quantities as waste but majorly under-utilised, a situation which causes serious environmental problems and health hazards when managed improperly. This work focussed on production and assessment of hygrothermal properties of solid core sandcrete blocks in which sand is partially replaced with sawdust at 0%, 10%, 20%, 30%, and 40% loading levels. Experiments were conducted on block samples made with untreated sawdust (USD) and on those similarly produced but with treated sawdust (TSD). The results showed that the blocks with USD content are capable of decreasing wall heat transmission load and improve energy efficiency of building envelopes better than their counterparts produced with TSD. In terms of compliance with standard bulk density and water absorption requirements, incorporation of USD or TSD at 20% or 10% level respectively, was found to be optimum for partial sand substitution in the studied block samples in order to suit the functional requirements of building structure and interior space. Since sawdust is cheaply and commonly available in vast amount, utilising it in sandcrete block production is a promising way of minimising its disposal problems while enhancing the development of safe, affordable, and sustainable housing.

Practical demonstrations by teacher and learner, especially in Science Education, make teaching-learning process pragmatic, learner-centred, easier to understand, and more appreciated. Also, it has been observed that radioactivity is one of the important topics in Physics and Chemistry at Secondary School levels. Unfortunately, its concept appears abstract and illusion in the minds of the learners due to lack of practical demonstrations or experimentation of the theory. The reason for such deficiency may be attributed to hazardous nature of radioactive substances, strict legal regulations on their exposures (both at the international and domestic levels), associated risk during transportation and handling, etc. The essence of this research is to devise a way of practically demonstrating radioactivity by utilising a non-radioactive substance that is cheaply available with high level of sustainability and potential to exhibit decay. Specifically, methylated spirit was used as the non-radioactive substance in this study. It was put in a syringe clamped vertically with an open end facing up and timing of its evaporation was performed separately for intervals of 10 minutes and 15 minutes. In each case, the volume of the methylated spirit left was recorded and the data obtained were analysed It was observed that the volume -- time relationships were of exponential decay characteristic supported by empirical formula governing radioactivity, notwithstanding the time intervals considered. For 10 minutes interval consideration, the results showed evaporation constant (which is analogous to decay constant), and half-life to be 8.14 x 10-4 min-1, and 851.4 minutes respectively whereas in the case of 15 minutes interval, they were found to be 8.40 x 10-4 min-1, and 825.0 minutes respectively. Hence, it could be adjudged that methylated spirit is a promising non-radioactive substance for practical experiment/demonstration to make teaching and learning of radioactivity learner-centred for a better understanding of the topic in Physics and Chemistry at Secondary School levels. [ABSTRACT FROM AUTHOR]

This study was designed to examine the feasibility of recycling cassava effluent, sawdust, and unused paper products to enhance their utilization for beneficial purpose. Waste newspaper paste (WNP), Waste writing – paper paste (WWP), and Waste carton paper paste (WCP) were prepared and then used separately to similarly fabricate composite panels with Sawdust particle (SDP) proportioned at 0%, 25%, 50%, 75%, and 100% by weight. The binder used was cassava starch slurry prepared from the effluent. Bulk density, water absorption, thermal conductivity, specific heat capacity, thermal diffusivity, nailability, and flexural strength were determined for the developed samples. From the results obtained, the samples were found to be light-weight and their thermal insulation performance improved with increasing proportions of the SDP. Though samples containing the WCP exhibited the best satisfactory performance, it was found that all the studied samples could perform more effectively and efficiently as ceilings compared to some of those reported in the literature. From scientific-economic viewpoint, valorizing the above-mentioned wastes as described in this paper could help to protect the environment and also yield value-added insulation ceilings for enhancement of sustainable building construction especially in tropical areas. [ABSTRACT FROM AUTHOR]

In this investigation, Clam, Periwinkle and Oyster shells were separately treated, calcined and ball-milled into nano powder. Each nano powder material was fabricated into disc of various lengths in three replicates. In each case, the electrical characteristics of the discs were determined. Electrical resistivity values obtained for test samples developed from Clam, Periwinkle and Oyster shells were found to be (6.024 ± 0.009) x 105 Ωm, (6.823 ± 0.030) x 105 Ωm, and (4.916 ± 0.007) x 105 Ωm respectively at a temperature of (25.0 ± 1.0oC). Also, electronic activation energy values were found to be 0.68eV, 0.61eV, and 0.76eV, while thermal sensitivity index values were obtained as 7850K, 7058K, and 8814K respectively for the samples fabricated from the shells of Clam, Periwinkle, and Oyster. The shell samples exhibit a negative temperature coefficient of resistance with values of - 8.83%/K, -7.94%/K and -9.92%/K for Clam, Periwinkle and Oyster shells respectively. These results provide data base on the electrical characteristics for the shells. It can be adjudged from the results that the shells are potential raw materials for NTC thermistor production. They have high sustainability and can be considered to be economically cheap since they are discarded as waste. [ABSTRACT FROM AUTHOR]