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Investigating bacterial diversity in the soil of oil palm plantations is crucial for developing effective soil management strategies to mitigate greenhouse gas emissions, thereby addressing climate change challenges. In this study, we analysed soil bacterial communities within an oil palm plantation in Sarawak, Malaysia. To capture the full spectrum of microbial diversity, samples were collected across three distinct soil depths and various managements zones within the plantation. We employed Illumina amplicon sequencing targeting the V3 region of the 16S rRNA gene, which revealed a diverse array of soil bacteria, primarily from the phyla Acidobacteriota, Actinobacteriota, and Proteobacteria. Notably, families such as RAAP2_2 and Isosphaeraceae were identified as key biomarkers predominantly inhabiting deeper soil layers (30-45 cm), while UBA7541, Streptosporangiaceae, and Sporichthyaceae were more prevalent in the surface layer (0-15 cm). Microbial correlation network analysis revealed a complex network of robust and significant interactions among 11 bacterial families, suggesting their involvement in plant material degradation and carbon cycling. Redundancy Analysis (RDA) revealed that pH, moisture content, and bulk density were significant factors that influence the microbial community structure. At the phylum level, Acidobacteriota showed a close association with pH, while Proteobacteria was associated with higher moisture content. Interestingly, we discovered that the soil was not as homogeneous as initially thought. Microenvironmental variability was evident, with specific groupings based on subplot sampled. These findings provide valuable insights into the factors shaping microbial communities in oil palm plantation soils, thus opening avenues for further exploration of the complex mechanisms driving ecosystem processes in this unique Malaysian soil environment.

The primary aim of this research is to conduct a comprehensive comparative experimental and statistical study on the flexural strength of a novel ternary blended high-performance M30 grade concrete incorporating 20% Alcofine in comparison to traditional concrete.The components employed in the experimental investigation of high-performance M30 concrete incorporating Alcofine, in contrast to conventional concrete, comprise cement, fine aggregate, coarse aggregate, water, Alcofine, and additional cementitious materials like fly ash and silica fume. The Flexural Strength of high-performance M30 concrete containing Alcofine significantly influences the performance of concrete structures, rendering it a critical mechanical property for examination in the comparative analysis. The mean flexural strength of the Conventional Concrete group measured 8.1111 N/mm^2, with a standard deviation of 0.75840 and a standard error of the mean of 0.17876. In contrast, the Ternary Blended Concrete group exhibited a higher mean flexural strength of 12.5000 N/mm^2, coupled with a larger standard deviation of 2.09341 and a standard error of the mean of 0.49342. The statistical power analysis, involving parameters such as alpha (α) and beta (β), with commonly used values of 0.05 or 0.01, indicates a significance level of 5% or 1%, respectively. Further research could delve into refining the optimal percentage of Alcofine and exploring its long-term performance under varying environmental conditions. Keywords: Ternary Blended Concrete; Alcofine; Flexural Strength; Comparative Analysis; Statistical Study

Nowadays HVDC transmission systems are preferred over HVAC systems because of their less power loss and high reliability. In the HVDC cable transmission system, there is a problem of Partial Discharges (PD) occurring due to cavities of the dielectrics in HVDC cables. The distribution of the electric field may change in the presence of partial discharge, which has an impact on how the electric system normally functions. Under DC conditions, partial discharge characteristics are influenced by the electric field distribution and electrical conductivity. Discharges tend to occur quickly when the cavity field reaches the inception level. Hence it is necessary to monitor the conditions of the HVDC cable for better transmission. A 2-D FEM-based model is developed for the simulation of PD due to various shapes of voids at various locations in the cable insulation using ANSYS. Also, PD modeling is the most important concern in identifying the influencing parameters and physical mechanisms of the PD phenomenon. In this work, the Three capacitances model is used to estimate the model parameters and simulate the partial discharges in MATLAB. The results from the simulation are compared with analytical models. It is observed that pulses of the partial discharges vary with the dimensions of the void, type of void materials, and location of the void.

The sensors can be developed based on ampherometric principle using Direct Methanol Fuel Cell (DMFC) technology. The synthesis of cost effective electrocatalyst materials for improved oxygen reduction reaction (ORR) and preparing electrodes by using suitable methods to reduce the cost of the sensing electrode is the major objective of the present work. Pt-Sn alloy exhibits high sensitivity in ORR among other Pt alloys and hence will be used as the ORR catalysts. For various concentration of methanol at different temperature, the current density of the chemically synthesised and characterized Pt-Sn/C was analysed. The accuracy will be determined by the detection of electric current or changes in electric current to design the sensor. To analyse the sensor accuracy, we have used passive mode design protocol in COMSOL Multiphysics. From the constructed cell of 1.0 cm cell area, we can optimize the overall power density and hence the sensitivity of the sensor by the modification of the cell parameters and interfacing it with Darcy’s law of fluidic flow through porous electrode medium. The micro electro mechanical systems (MEMS) technology was used for the design and fabrication of sensor with the electrochemical inputs from a standard DMFC single cell arrangement. The cell structure has been fabricated using a 3D printing technology and the output of the cell was optimized for ampherometric detection. The sensor with microfludic interconnects were fabricated by MEMS technology. The sensor response characteristics were studied and will be presented.

Turnover intentions in academic institutions has become one of the main concern of the management as surviving and achieving excellence is very much about having the knowledgeable and committed employee. Therefore, it is one of the main and foremost issue for a management of higher education institution to give important. There are many factors that influence an academician to have turnover intentions. Hence, this study’s focus was to investigate the relationship between role ambiguity, work-overload, work family conflict, co-workers warmth, co-workers competence and turnover intentions. The variables studied in this paper were analyse from a research framework. The finding of this study has been discussed on role ambiguity, work-overload, work family conflict, co-workers warmth, co-workers competence and turnover intentions. Conclusion has been drawn from the support of literature that states that the variables influences on turnover intentions. This paper’s finding provides valuable guidance for researcher and practitioners to overcome and improve the current mechanism to reduce turnover intentions. The research has also found few new paths for thinking on how to manage employees that having turnover intentions in any organizations.

Reinforced concrete beams with discrete hooked-end steel fibers at 0.5% volume fraction are tested with a shear span to depth (a/d) ratio equal to 1.8. Digital image correlation (DIC) technique was used to obtain the full-filed displacements from the beam. The formation and propagation of a shear crack which directly influences the load response and the peak load in the load response of the beam is monitored using the displacement information available from DIC. There is a continuous increase in slip across the crack faces with increasing load, which produces an increase in the crack opening. The dilatant behavior indicated by the proportion of crack opening to slip displacement obtained from the control and the SFRC beams is identical. Failure in control beams is brittle and was produced by the opening of dominant shear crack within the shear span. At the peak load, the shear crack pattern in fiber reinforced concrete is identical to the crack pattern in the control beam. The fiber reinforced concrete beams exhibit post peak load carrying capacity with continued slip of the dominant shear crack. The crack bridging stress provided by the fibers results in a significant increase shear transfer across the crack which provides significant post-peak load carrying capacity with increasing slip of the shear crack.

Good indoor environmental quality is desired for a healthy indoor environment. The microbial growth under indoor environments contribute to the poor indoor environmental quality that can cause various of health problems. In this study, the applications of three types of antifungals to prevent microbial migration, subsequent growth and bio-deterioration of the substrates. The aim of this research was to evaluate the coating-bio resistance in remediation of indoor fungal using three types of antifungals with different types of wall finishing materials. The treatment was exposed to optimum temperature and relative humidity at 30°C and 90% respectively. The potassium sorbate, zinc salicylate and calcium benzoate are tested against Aspergillus niger which is collected from indoor rooms. This study has revealed the growth of A. niger are more affected by the potassium sorbate on thick wallpaper, which is the percentage growth are 47%.

This paper reports the first ever characterization of the use of raw Garden Croton (locally known as ‘pokok puding’) leaf powder as low cost biomaterial for Cr(VI) removal. Biosorption experiments were carried out at ambient temperature to study the effects of initial pH (1-7), contact time (15, 30, 45, 60 min), leaf powder’s particle size (≤ 150, 151-300, 301-500 μm), and initial Cr(VI) concentrations (10, 20, 40, 60, 80 and 100 mg/L) towards Cr(VI) uptake. Optimum Cr(VI) uptake was observed at pH 1 (2.41 mg/g) and 2 (2.19 mg/g) (p > 0.05). The leaf powder in the 151-300 μm size displayed better Cr(VI) uptake up to 2.77 mg/g (77.78%; Co = 100 mg/L) at pH 2, after 30 min (p < 0.05). Equilibrium metal uptake fitted best (R2 = 0.927) to the Freundlich isotherm model (Kf = 0.21 mg/g, n = 1.23) indicating biosorption onto a heterogeneous surface of active sites. Morphological and elemental analyses by SEM/EDX and FTIR confirmed Cr retention, and presence of active chemical moieties. Interestingly, XRD revealed that Cr was immobilized within the biomass leaf powder in both forms, i.e. hexavalent, Cr(VI) as chromatite (CaCrO4) and trivalent Cr(III), as chromium(III) oxide (Cr2O3). Overall findings support the feasibility of the leaf powder as potential biomaterial for water pollution abatement.

The role of individual reactive components and process variables such as molarity and temperature on alkaline activation of different low-calcium fly ash is explored. The oxide ratios in the activated system, based on the total silica (total SiO2) in the system consisting of the reactive silica contributed by fly ash and the reactive alumina in fly ash are shown to provide consistent results for achieving the highest strength. For a given total SiO2 content in the system, an increase in the sodium content above a certain dosage does not influence the ultimate compressive strength. An optimum (total SiO2) to Na2O ratio, equal to 2.66 is established for achieving maximum strength. The role of temperature within the range of 60°C-85°C is not significant when the molarity of NaOH is high. A N-A-S-H type gel with Si/Al ratio ranging between 2.5 to 3.0 and the Al/Na ratio varying between 1.30 to 0.9 is formed on decreasing the (total SiO2)/Na2O ratio from 6.55 to 2.66

Buildings are a vital component in a human’s daily life. It provides shelter from the environment, weather and animals. Mold growth within the building might be caused by the moisture problems which directly act on it such as water leaks or indirect factor such as high humidity levels. This growth causes esthetic problems and deterioration of its wall coatings. Spores from the fungi also cause health problems to humans. The fungus species studied in this research is Aspergillus niger. The material is made of wood and its finishing is thick wallpaper, thin wallpaper, acrylic paint and glycerol based paint. ASTMD5590-00 standard was used to evaluate fungal growth and to determine if non antifungal agent was effective in inhibiting the amount of fungal growth on four types of wall finishing used on wooden walls. This research was conducted without using any antifungal agent. Highest percentage of growth of the fungi was found on acrylic paint, followed by glycerol based paint and thin wallpaper. Thick wall paper shows the least growth of fungi. The maximum growth is visible on day 12 which is more than 60% by all the wall finishing.

The common sources of water pollution in Malaysia are domestic sewage and industrial waste. Therefore, domestic wastewater quality effluent should be improved before discharged through the outlets. The alternative method of treatment uses microalgae for water remediation which is known as phycoremediation was applied. This technique is to remove or reduce nutrients and harmful pollutants in domestic wastewater. Thus, objective of the present study is to bioremediate the physiochemical and heavy metal from domestic wastewater using freshwater green microalgae Botryococcus sp. A photobioreactor is used to treat the wastewater by employing the microalgae Botryococcus sp. as a vital part of the treatment system. The results show that several nutrients have been reduced successfully such as phosphate and total phosphorus of 100% removal, inorganic carbon of 99% removal, total carbon of 42% removal, and nitrate of 10%. The most prominent heavy metal content that has been removed is Aluminium of 41%. At the same time, the growth of microalgae Botryococcus sp. in this wastewater has achieved the maximum value at Day 4 with 2.58 × 105 cell/ml only. These results show the potential of Botryococcus sp. cultivation as an alternative method to treat domestic wastewater and any other biotechnology works in the future.