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Foam composite panels made from hybrid fillers are materials developed to have low density with high mechanical properties. This work focuses on improving the mechanical properties of epoxy-based foam composite panels with hybridized fillers by combining hollow glass microspheres (HGM) and nanoclay. The HGM content was varied from 1 wt.% to 3 wt.% in foam composites panel, while nanoclay content was varied from 1 wt.% to 5 wt.% in each of the HGM-filled series of foam composites panel, these foam composite panels were fabricated using a conventional resin casting method. The mechanical properties such as tensile strength, impact strength, hardness, flexural strength of the prepared hybrid-filled foam composite panels were determined and compared with the neat epoxy. It was found that the hybrid-filled foam composite panels exhibited improved mechanical properties than the neat epoxy. These improved properties were because of excellent interfacial adhesion between the hybrid fillers and the matrix. The improved mechanical properties could suggest that this material may be suitable for application in industries where lightweight materials with good mechanical properties are required. This study showed a new area of synthetic foam development research by enhancing mechanical properties using hybrid-filled. KEYWORDS fillers, foam composite panels, hollow glass microspheres, mechanical properties, Nanoclay, 1 | INTRODUCTION Epoxy-based foam composites are lightweight materials with attractive mechanical properties, hollow structures, very good adhesion, good chemical properties, heat resistance, low shrinkage, corrosion resistance, and excellent electrical [...]

This study was conducted to predict the grain yield of a maize crop from easy-to-measure growth parameters and select the best treatment combinations of biochar, inorganic fertilizer, and irrigation for the maize grain yield and water use efficiency (WUE) using the Principal Component Analysis (PCA) technique. Two rates of biochar (0 and 20 t ha−1) and fertilizer (0 and 300 kg ha−1) were applied to the soil, with maize crop planted, and subjected to deficit irrigation at 60, 80, and 100% of full irrigation amounts (FIA). Maize growth parameters (number of leaves—NL, leaf area—LA, leaf area index—LAI, and plant height—PH) were measured weekly. The results showed that the developed principal component regression (PCR) from the easy-to-measure growth parameters were strong and moderate in predicting the maize yield and WUE, with coefficient of determination; r2 values of 0.92 and 0.56, respectively. Using the PCA technique, the integration of irrigation with the least amount of water (60% FAI) with biochar (20 t ha−1) and fertilizer (300 kg ha−1) produced the highest ranking on grain yield and water use efficiency. This optimization technique showed that with the adoption of the integrative approach, 40% of irrigation water could be saved for other agricultural purposes [ABSTRACT FROM AUTHOR]

A 2-year field experiment was conducted to test the effects of individual and co-application of biochar and inorganic fertilizer on soil quality using the principal component analysis (PCA) technique. The dry season field experiments were performed with biochar applied at 0 and 20 t ha−1, and fertilizer at 300 and 0 kg ha−1 (control). The factorial combinations of the above-mentioned treatments were subjected to irrigation at 60, 80, and 100% of irrigation amounts (IAs). Soil hydro-physical and chemical properties and grain yield were determined at harvest. Results from the PCA indicated that the soil total nitrogen (N) and moisture content (MC) were the soil properties mostly affecting the grain yield. The amendments' effects on the soil physico-chemical properties and maize yield were in the order control < biochar < fertilizer < biochar + fertilizer. The derived comprehensive soil quality index (CSQI) from the PCA showed that the soil quality increased by 76, 100, and 200% in treatments individually applied with biochar, inorganic fertilizer, and the co-applications. This study therefore showed that the PCA revealed the actual dynamics in soil properties, in terms of the SQI upon the soil amendment addition, as well as their relationship with maize yield under different weather conditions. [ABSTRACT FROM AUTHOR]

Plant seeds can harbour pathogens that limits crop growth and productivity. This study isolated, characterised and evaluated native Trichoderma harzianum for antagonism against five (Alternaria alternata, Aspergillus oryzae, Bipolaris oryzae, Curvularia lunata and Fusarium verticillioides) fungal pathogens isolated from rice seeds. Evaluation was through simultaneous inoculation, a pathogen against the biocontrol agent, using the dual culture method in a PDA growth medium. Results confirmed the T. harzianum isolate had 98.27% pairwise identity with T. harzianum P39 (KX381171.1. accession number). The isolate showed increasing percentage inhibition, against all the pathogens, with increasing days after inoculation. The highest values ranged from 53.02%, A. oryzae to 70.06%, F. verticillioides (the least and most susceptible respectively). The overall inhibition percentages of A. alterata and B. oryzae (12th day after inoculation) were not significantly different from that of F. verticillioides. Trichoderma harzianum P39 can be formulated as biological seed dressing agent. [ABSTRACT FROM AUTHOR]

The impact of charcoal production on soil hydraulic properties, runoff response and erosion susceptibility were studied in both field and simulation experiments. Core and composite samples, from 12 randomly selected sites within the catchment of Kotokosu were taken from the 0-10 cm layer of a charcoal site soil (CSS) and adjacent field soils (AFS). These samples were used to determine saturated hydraulic conductivity (Ksat), bulk density, total porosity, soil texture and color. Infiltration, surface albedo and soil surface temperature were also measured in both CSS and AFS. Measured properties were used as entries in a rainfall runoff simulation experiment on a smooth (5 % slope) plot of 25 x 25 m grids with 10 cm resolutions. Typical rainfall intensities of the study watershed (high, moderate and low) were applied to five different combinations of Ks distributions that could be expected in this landscape. The results showed significantly (p < 0.01) higher flow characteristics of the soil under charcoal kilns (increase of 88 %). Infiltration was enhanced and runoff volume reduced significantly. The results showed runoff reduction of about 37 and 18 %, and runoff coefficient ranging from 0.47-0.75 and 0.04-0.39 or simulation based on high (200 mm h-1) and moderate (100 mm h-1) rainfall events over the CSS and AFS areas, respectively. Other potential impacts of charcoal production on watershed hydrology were described. The results presented, together with watershed measurements, when available, are expected to enhance understanding of the hydrological responses of ecosystems to indiscriminate charcoal production and related activities in this region.O impacto do processo de produção de carvão nas propriedades hidráulicas, a resposta ao deflúvio e a suscetibilidade do solo à erosão foram estudados em experimentos de campo e de simulação. Amostras indeformadas e compostas de 12 locais aleatoriamente selecionados dentro do reservatório de Kotokosu foram coletadas na camada de 0-10 cm no solo sob carvão (CSS) e no solo adjacente (AFS). Essas amostras foram usadas para determinar a condutividade hidráuli7ca saturada (Ksat), densidade do solo, porosidade total, textura e cor do solo. A infiltração, o albedo de superfície e a temperatura de superfície do solo também foram medidos no CSS e AFS. Os parâmetros medidos foram usados como entrada nos experimentos de simulação de deflúvio em uma parcela uniforme (5 % de declividade) de 25 x 25 m, com grides de 10 cm de resolução. Altas, moderadas e baixas intensidades de chuva, típicas da bacia em estudo, foram aplicadas em cinco diferentes combinações de Ksat, que poderiam ser esperadas nessa paisagem. Os resultados mostraram que as características do fluxo do solo sob carvão aumentaram significativamente (p < 0,01) em 88 %. A infiltração foi aumentada e o volume de deflúvio reduzido significativamente. Houve redução no deflúvio em torno de 37 e 18 %, e o coeficiente de deflúvio variou de 0,47-0,75 e 0,04 a 0,39 para a simulação de chuvas de alta (200 mm h-1) e moderada (100 mm h-1) intensidades nas condições CSS e AFS, respectivamente. Outros impactos em potencial da produção de carvão na bacia hidrológica foram observados. Espera-se que, com os resultados aqui apresentados, além dos determinados na bacia, quando disponíveis, haja uma compreensão melhor das respostas hidrológicas do ecossistema de fabricação indiscriminada de carvão e de outras atividades relacionadas nessa região.

Infectious diseases caused by microorganisms are widespread health risks associated with drinking water. This study evaluated the physicochemical parameters and bacteriological quality of the stream and well water using standard protocols. The bacteria were identified by conventional and molecular methods. Antibiotic susceptibility and location of antibiotic resistance markers (ARMs) were determined using disc diffusion and acridine orange, respectively. The highest mean Total Heterotrophic Bacterial Counts (THBC), Total Coliform Counts (TCC) and Faecal Coliform Counts (FCC) from the stream water was 4.3 ± 0.3×106, 8.9 ± 0.0×105, and 3.5 ± 0.1×104 (CFU mL-1), respectively. The well water had mean TCC ranging between 2.8 ± 0.0×10³ and 2.1 ± 0.1×104 (CFU mL-1). Six bacterial genera: Staphyloccocus, Pseudomonas, Escherichia, Enterobacter, Klebsiella, and Shigella were isolated. The mean temperature of the water ranged from 26.0 ± 0.3℃ to 27.0 ± 0.1℃. The highest mean dissolved oxygen, total hardness, sulphate and magnesium was 24.0 ± 1.0, 40.1 ± 0.8, 11.0± 1.0, and 67.0 ± 1.5 (mg L-1), respectively. The results showed that ≥ 66.7 S. aureus were Levofloxacin and Streptomycin sensitive; between 45.5 and 68.1% of the isolates were Gentamycin and Chloramphenicol resistant, while 81.8% exhibited multidrug resistance. Escherichia coli EcSW3, E. aerogenes EeWW2, K. pneumoniae KpSW3, and S. aureus SaSW had their entire ARMs located on the plasmids with the molecular sizes < 2.027 Kbp. This study showed that the stream and well water harboured bacteria with some ARMs on plasmids, indicating the possibility of horizontal transfer of antibioticresistant genes among the bacteria. In addition, it showed the necessity to enlighten the rural populace on the importance of cleaning the surroundings near water sources so as to prevent water-borne diseases. [ABSTRACT FROM AUTHOR]