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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]

Large quantities of waste newspapers and sugarcane bagasse are prevalently discarded by open burning or indiscriminate dumping, thereby posing severe danger to the environment and public health. This study sought to examine the feasibility of managing the wastes by recycling them into value-added products for building construction. Composite panels were fabricated using waste newspaper paste (WNP) with sugarcane bagasse particles (SBP) varied at 0, 25, 50, 75, and 100 % by weight of the composite mix. Epoxy resin was thoroughly mixed with its hardener and applied as binder. The samples were developed in triplicates per proportion of the SBP adopted and then dried completely before their thermophysical and strength properties were evaluated. It was observed that variations in mean values of water absorption (28.57 – 39.43 %), thickness swelling (6.21 - 8.33 %), specific heat capacity (1232 - 1312Jkg−1K−1) trended positively with increasing proportions of the SBP. Whereas nailability remained 100.0 % in all the cases, bulk density (689.4 - 640.5 kgm−3), thermal conductivity (0.1186 - 0.1163 Wm−1K−1), thermal diffusivity (1.396 - 1.384 x 10−7 m2s−1), and flexural strength (2.572 - 2.280 N/mm2) correlated inversely with the added fractions of the SBP. Generally, it was found that the samples could perform satisfactorily if applied as ceiling or partition elements in building design. Therefore, recycling of sugarcane bagasse and waste newspapers as described in this study could serve as a promising way of solving their disposal problems and also enhance achievement of low-cost and safe buildings. [ABSTRACT FROM AUTHOR]

The literature is flooded with scientific information on most durability properties except water absorption coefficient of masonry units like sandcrete blocks. Also, while waste papers disposal is a systemic problem due to ineffectiveness of waste management system in developing countries, the price of cement is on the increase. This situation, ultimately, causes a bane in achievement of low-cost housing development considering the fact that sandcrete blocks are predominantly used as walling elements for such undertakings. In this study, solid core sandcrete blocks were produced with waste paper ash (WPA) utilized as partial replacement of cement at 5 % and 10 % volumetric levels. Chemically, the WPA was found to show similarity with cement in terms of SiO2, Al2O3, and CaO contents. Density and water absorption coefficient of the block samples were determined. While density ranged from 1682 to 1872 kg/m3, water absorption coefficient varied from 27.04 to 23.49 kg/m2h0.5. Statistically, no significant difference was revealed at p < 0.05 between experimentally-measured water absorption coefficients and those obtained using the model developed for prediction based on density of the samples. Thus, utilization of WPA as described herein could help to reduce the cost of procuring cement and in turn, enhance low-cost building construction. Also, with the developed model (showing dependence of water absorption coefficient on density), durability of sandcrete blocks exposed to moisture –prone environment could be easily predicted. [ABSTRACT FROM AUTHOR]

Coconut husk is generated yearly as waste in large quantities but majorly under-utilized. Also, as a result of high embodied carbon, cement production is one of the largest contributors to construction sector carbon footprint. Since accumulation of unmanaged agro-waste like coconut husk has an increased environmental concern due to its pollution effect, recycling it into sustainable construction materials is a viable solution for future generation. In this study, experiments were performed to investigate the influence of coconut husk ash nanomaterial (CHAN) inclusion on electrical characteristics of plain cement paste (BCP) and mortar (CSM) samples at curing ages of 7 and 28 days. The results showed increase in electrical resistivity, thermal constant, and activation energy with curing duration for heating and cooling cycles of BCP and CSM. With inclusion of CHAN, the developed cement paste (CAP) and mortar (CASM) possessed lower values in all cases compared to their counterparts. Also, during heating at 28 days, both the CAP and CASM exhibited decrease in thermal constant. Though electrical resistance of all the samples varied inversely with temperature, CAP and CASM were found to possess greater potentials to make building structures intrinsically smart. Hence, in addition to solving disposal problems, utilization of coconut husks as described herein could enhance development of safe, inexpensive, and sustainable buildings that have large temperature sensing volume. [ABSTRACT FROM AUTHOR]

Thermophysical properties of clay sample obtained from Agbani in Enugu State, Nigeria, were investigated, analyzed and compared with similar properties reported for some walling and roofing materials, including clay samples from other locations for the purpose of establishing its suitability as walling material for the design of naturally-cooled building. Agbani clay sample exhibits bulk density value of (2111.4 ± 13.1) kgm-3, specific heat capacity value of (1253.99 ± 2.03) J/kgK, thermal conductivity value of (0.1105 ± 0.0014) W/mK, thermal resistivity value of (9.05 ± 0.11) W-1mK, thermal diffusivity value of (4.17 ± 0.06) x 10-8 m²s-1, and thermal absorptivity value of (29.52 ± 0.42) m-1. The outcome of the comparison of the values obtained with values of similar properties reported for other walling materials evidences that Agbani clay is a better choice material for the design of naturally-cooled building [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]

This work sought to assess the suitability of using boards produced with plaster of Paris (P.O.P) and various weight proportions of groundnut seed coat (GSC) as well as P.O.P and similar proportions of waste newspaper paste (WNP) as ceiling in building design. The results obtained from the investigation of thermal and mechanical properties of the fabricated boards revealed that with the use of GSC as filler, the samples were of higher mean values of specific heat capacity, thermal conductivity, thermal absorptivity, but lower mean values of bulk density, thermal diffusivity, percentage water absorption, flaking concentration and flexural strength when compared to the samples with similar proportions of WNP as filler content. Also, the sample with 13.8% content of GSC and the one containing 22.5% of WNP were found to exhibit an impressive performance. Generally, it was observed that the samples filled with either GSC or WNP were lighter than pure P.O.P samples and the recorded values for all the measured properties favoured them for use as ceiling material in buildings. It is noteworthy that the proportion of the filler can be adjusted for optimum performance of such environmentally-friendly and cost-effective ceilings. Utilizing groundnut seed coat and waste newspapers as filler materials in fabrication of P.O.P ceiling can help to reduce environment pollution level, ensure better thermal insulation of buildings and solve the lingering problem of high cost of using P.O.P or other conventional materials as ceiling in buildings by the end-users. [ABSTRACT FROM AUTHOR]

In this work, a modified water displacement method (MWDM) was designed and used alongside geometry method (GEM), overflow method (OFM) and water displacement method (WDM) for determination of bulk volume of a porous solid. Their results were analyzed graphically and statistically. On testing against the data obtained by Suspension/Buoyancy Method (SBM) used as gold standard, it was found that only those generated by the modified water displacement method (MWDM) were of very high accuracy and precision. Apart from its reproducibility being within the recommended range for acceptability of a test method, the technique is cost-effective and easy to apply even with an ungraduated glass cylindrical tube. This can go a long way in enhancing thorough physical characterization of porous solids without the use of high cost, sophisticated and complex equipment. [ABSTRACT FROM AUTHOR]