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Rough neutrosophic multisets (RNM) is an uncertainty set theory generalized from the rough neutrosophic set. In the same equivalence relation, the universal set is a neutrosophic multisets with boundary regions involving lower and upper approximation. To date, to handle the multiplicity of information collected, the rough neutrosophic multisets geometric aggregation operator (RNMGAO) is introduced. The algebraic operations of RNM used in the derivation of RNMGAO are defined. The entropy measure of RNM is also discussed as a weighted assign for each criterion simultaneously with the geometric aggregation operator. The roughness Dice similarity measure of RNM is combined in methodology for ranking purposed. The application in medical diagnosis of three epidemic diseases Coronavirus, Influenza, and Pneumonia is implemented as a case study.

Energy consumption in residential buildings soared enormously during the pandemic. To construct highly efficient residence, materials are one of factors that need to be considered due to their impact of climate change, power consumption and operational cost. It was found that power plants produced various types of waste products that can be utilized in many applications. For instance, Cenosphere produced from power plants could promote thermal properties of mortar brick to a certain extent. The aim of this study is to evaluate the effects of Cenosphere as partial sand replacement on thermal properties of mortar and buildings’ energy efficiency at different percentages (0%, 5%, 10%, 15% and 20%). Both thermal conductivity and specific heat capacity were detected by using Fox 50 instrumentation while energy efficiency was determined by using Autodesk Revit and Green Building Studio (GBS) software. The findings of thermal properties show that the replacement of sand with 20% Cenosphere as partial sand replacement have significantly reduces thermal conductivity while increasing the specific heat capacity of mortar. This study revealed that the k value of mortar bricks have reduced as low as 0.62 W/m.K and as high as 932 J/kg.K for specific heat capacity due to incorporation of Cenosphere and mixtures at 20%. On the other hand, the EUI of 5% Cenosphere has reduced 2.13 kWh/m2 or 1.4% lower than control mix. The energy saving measure largely influenced by the composition of Cenosphere as compared to the buildings’ orientations.

Coal combustion by Products (CCPs) are produced during coal combustion in the process of electric generation. Without proper handling system, this will cause serious problems towards human and environmental. Nevertheless, with proper treatment, these ashes are applicable in many areas specially building construction materials. Coal Bottom Ash, Coal Fly Ash and Cenosphere are three main wastes produced from power plant. The aim of this study is to determine the characteristics of samples collected from different parts of Malaysia Power Plant. Characterization testing involved included surface morphology, chemical composition (oxides), chemical components, amorphousness, and particle size distribution testing. From this study, CBA have more angular-shaped particles compared to CFA which is smoother surface morphology. However, Cenosphere shown the most uniform and spherical shaped particles. EDS testing shown Existing CBA have highest Carbon content (46%) while Cenosphere is lowest (11.38%). The percentage oxides contents for all samples demonstrate more than 70% of Total SiO2 + Al2O3 + Fe2O3. Hence, all ashes considered as Class F (pozzolanic). CBA, SFA, CFA and cenosphere has significantly more amorphous phases of silica and alumina, and this will increase the concrete strength. Due to agglomeration of ashes on ash pond, the cumulative PSDs results shown that the particle size of the existing sample obtained larger than the new sample. Minimum particles size of SFA (New Dry) is 2 µm while SFA (Existing 2) is 20 µm. From characteristic determination above, it shown that each type of ashes has its own uniqueness and capability to be applied wide range of applications.

The escalating demand for construction materials, coupled with the depletion of natural resources such as sand, necessitates environmentally conscious alternatives in concrete production. This study investigates the viability of utilizing bottom ash as an eco-friendly substitute for natural sand in roller compacted concrete (RCC). The focus is on evaluating workability and mechanical properties, examining bottom ash replacements at 0%, 20%, 25%, and 30% for fine aggregate. The research employs a comprehensive methodology, assessing workability and mechanical strength, encompassing compressive, split tensile, and flexural strengths across various concrete formulations. Comparative analyses with conventional concrete provide conclusive insights. Significantly, the study consistently highlights the superiority of RCC specimens featuring a 25% bottom ash replacement, exhibiting the highest strength values. This establishes the 25% replacement ratio as optimal for achieving robust roller-compacted concrete. Despite a slight reduction in workability with increasing bottom ash replacement, it remains within acceptable limits for practical applications. Comparative analyses between bottom ash RCC and conventional RCC underscore the superior mechanical attributes of the former, suggesting its potential as a sustainable alternative in concrete construction. By substituting natural sand with bottom ash, this research addresses environmental concerns related to the depletion of sand reserves. It actively contributes to sustainable practices within the concrete industry, demonstrating the viability of bottom ash as a substitute for natural sand in roller compacted concrete production. In conclusion, the study advocates for environmentally friendly practices and offers a practical solution to mitigate the ecological impact of sand resource depletion in the realm of concrete construction. The findings emphasize that the optimum percentage of bottom ash for compressive strength, split tensile strength, and flexural strength tests is within the range of 0% to 12%.

Nature inspires innovative renewable energy solutions by advancing our road pavements, as the sun is the only infinite and accessible source of clean and green energy on our planet. In addition to the various solar energy production methods, a new paradigm for utilizing asphalt pavement as a solar collector is being developed for self-powered energy harvesting. Due to direct solar radiation, flexible paved surfaces exposed to direct sunlight can heat up to 70°C in the summer. The heat is then dissipated into the environment, causing the urban heat island effect, and accelerating thermal oxidation of asphalt pavement. This can lead to structural failure and reduced pavement performance. This study aims to present a state-of-the-art review of hydronic asphalt solar collectors (HASCs) and propose the best model to enhance the performance of asphalt solar collectors. The findings of the study concluded that asphalt has the potential to absorb solar energy and store heat energy. This can be achieved by assembling and modifying conventional asphalt structures into modern asphalt solar collector designs that consist of pipe arrangements below the paved surface filled with liquid flowing through the pavement surface. The study found that a significant limitation of previous research was that it focused on optimizing the temperature profile at various depths but did not focus on structural improvements to reduce failure and increase the performance of asphalt solar collectors. Therefore, this review study proposed a new technique of using conductive and waste materials to enhance the performance of asphalt solar collectors.

This study aimed to investigate the characteristics of roller-compacted concrete when fine aggregate is replaced with fly ash. The investigation focused on assessing workability, compressive strength, flexural strength, and split tensile strength of the concrete mixtures. Four testing methods were employed, including the slump test for workability assessment, the compression test for determining compressive strength, the flexural test for evaluating flexural strength, and the split tensile test for measuring split tensile strength. The fly ash used in this project was sourced from the powerplant in Malaysia. Various fly ash contents, specifically 0%, 55%, 65%, and 75%, were utilized to replace the fine aggregate. The concrete mixtures were subjected to water curing for 7, 14, and 28 days before testing. Following the mixing process using a concrete mixer, the mixtures underwent a slump test to evaluate their workability. It was observed that the workability of the concrete decreased as the percentage of fly ash used to replace the fine aggregate increased. Mixtures with fly ash exhibited zero slump, while the control mixtures displayed true slump. Subsequently, compression, flexural, and split tensile tests were conducted after 7, 14, and 28 days of water curing. In terms of compression strength, an increase in fly ash content resulted in higher compressive strength in the concrete mixtures. The mixture with 65% fly ash content demonstrated the highest compressive strength at 49.84 MPa. Regarding flexural strength, the concrete with 75% fly ash content exhibited the highest value, measuring 5.45 MPa. However, for split tensile strength, the concrete without fly ash content showed the highest value at 8.84 MPa compared to other mixtures, indicating that the fly ash content exceeded the optimum amount for the mix design. In summary, the concrete mixtures with fly ash displayed several advantages, but their suitability depends on the specific type of construction.

AbstractWastewater treatment plant sludge contains a high concentration of organic compounds that can be used to produce fuel viahydrothermal carbonization (HTC). This study investigated the combustion reactivity and kinetic parameters of hydrochars produced to understand the combustion behavior of the solid fuel derived from HTC. The hydrochar was produced at various temperatures ranging from 150 to 300 °C, reaction times ranging from 30 to 150 min, and solid loadings ranging from 10% to 30%. The combustion behavior of sewage sludge (SS) and hydrochar was evaluated using thermogravimetric analysis with a constant air flow rate (100 mL/min) and heating rate (10 °C/min) from ambient temperature to 900 °C. It was observed that the HTC temperature, reaction time, and solid loading influenced the combustion characteristics and kinetics of the hydrochar. Additionally, the hydrochar exhibited higher ignition and burnout temperatures and a lower peak temperature than SS, indicating superior performance and reactivity in combustion. The combustion kinetic analysis also revealed that the hydrochar had a range of lower activation energy (29.12–41.60 kJ/mol) than SS (52.95 kJ/mol). Therefore, hydrochar derived from SS has the potential to be used as a substrate for solid fuel production for future renewable energy sources. [ABSTRACT FROM AUTHOR]

This paper presents the effects of incorporating thienyl and phenyl rings as the terminal ring in the cinnamoyl counterparts of chalcones with donor-acceptor-donor (D-A-D) push-pull setting, on their photophysical responses. Two fluoro-methoxy substituted chalcone derivatives with distinct cinnamoyl systems, 4-methylthiophene-2-carbaldehyde (2F4MA48) and 2,4-dimethylbenzaldehyde (2F4MA96), were synthesized. Characterization of these chalcone derivatives was performed using nuclear magnetic resonance (NMR), Fourier-transform infrared (FTIR) and single-crystal X-ray diffraction (SCXRD). Comparative studies on the linear and nonlinear optical responses were carried out through both experimental analyses and theoretical density functional theory (DFT) calculations. The electronic absorption spectra computed using DFT were compared with the UV-Vis spectra to elucidate the intramolecular charge transfer mechanism via the hole-electron distribution and interfragmentary charge transfer analyses. Molecular properties were examined through electrostatic potential (ESP) maps, π-electron localization function (ELF-π), and frontier molecular orbitals (FMOs). The incorporation of thienyl ring is found to give a stronger push-pull effect and greater electron delocalization. Experimental nonlinear optical responses were investigated using Z-scan technique with a continuous-wave incident laser at a wavelength of 532 nm. Both compounds showed two-photon-induced reverse saturation absorption (RSA) and self-defocusing responses. It was observed that the thienyl-based chalcone, exhibited greater optical nonlinearity in terms of nonlinear absorption (NLA), nonlinear refraction (NLR), and optical limiting. The experimental third-order nonlinear optical susceptibility (χ(3)) was determined to be 8.04 × 10−8 esu for 2F4MA48 and 1.08 × 10−8 esu for 2F4MA96. The onset limiting threshold (FS) was found to be 2.63 kJ cm−2 for 2F4MA48 and 5.23 kJ cm−2 for 2F4MA96. The steep optical limiting traces of 2F4MA48 show superior performance compared to 2F4MA96.