Journal of Brilliant Engineering (BEN)

Md. Osman Gani Rasel Md. Mahabub Rahman Md. Mahfuj Ahmed Sizan

The current study aimed to quantifying the spatiotemporal variation of land surface temperature (LST) and investigate its association with vegetation greenness, built-up areas, and salinity in Khulna District of Bangladesh between 2002 and 2020 by processing MODIS derived products in Google Earth Engine (GEE) platform. The Mann–Kendall (MK) test and Sen's slope estimator were used to quantify temporal trends while the Pearson correlation analysis was employed to examine relationships among the variables. Results did not show any long term statistically significant monotonic trend at the district scale of the LST (τ= 0.0435, p=0.3304) with an estimated trend of 0.002°C/yr. The monthly mean LST values varied between 20.9°C and 32.3°C and were higher in peri-urban and urban areas in general. The normalized difference vegetation index (NDVI) had a significant positive trend (0.0002 yr-1, with τ=0.1365, p=0.0023), but had a very weak and non-significant relationship with LST (r=0.0455, p=0.4964). The normalized difference built-up index (NDBI) showed a slight decreasing trend (−0.0002 yr⁻¹; τ=−0.1276, p=0.0043), whereas LST was weakly positively correlated with built-up intensity (r=0.16, p=0.016), probably due to spectral mixing and surface reflectance properties rather than actual decreases in urbanization. No significant temporal trend was observed in the spectrally derived salinity proxy but there was a weak positive correlation with LST (r=0.18, p=0.0054) especially near coastlines. However, all these statistically significant relations explained less than 4% of the LST variance (R² < 0.04) and suggested that other climatic and environmental factors have the main influence on the variability in LST.

https://doi.org/10.36937/ben.2026.41138

Ali Zeynalli Derya Tekin

Patterns materials used in green sand molding lines are continuously exposed to abrasive sand particles and repetitive mechanical loads, which can affect their dimensional stability and service life. In this study, the dimensional wear behavior of GG25 gray cast iron and GGG50 ductile cast iron patterns materials was investigated under industrial green sand molding line conditions. Wear performance was evaluated using weight loss and dimensional changes after 16,794 molding cycles, while surface roughness was assessed only for the initial machined condition. The results showed that both materials exhibited relatively similar dimensional wear behavior under the conditions studied. However, GG25 cast iron was observed to exhibit a lower measured mass loss and a relatively smoother surface texture. These observations suggest that material-dependent differences may affect wear performance during operation. Surface roughness was measured before molding to characterize the initial machined surface finish. Furthermore, due to the limited number of cycles, variations in sample geometry, and the absence of repeated samples and direct microstructural characterization, the results should be interpreted cautiously. The findings provide a preliminary insight into the dimensional wear behavior of cast iron patterns materials under real industrial operating conditions and may form a basis for future studies involving larger sample sizes and more comprehensive material characterization.

https://doi.org/10.36937/ben.2026.41143

Nirmal Chandra Roy Md. Monowar Hossain Santoi Mst. Fihima Tabach Chum Hema

Improving building energy efficiency requires careful selection of heat insulation systems that balance engineering performance with economic feasibility. This paper examines two indigenous roof retrofit approaches (roof top garden and polyurethane foam) based on hourly temperature and relative humidity over six months for the city of Dinajpur, Bangladesh. The paper generates 24 hour profiles of temperature and humidity from February through July, comparing indoor/ceiling conditions for each technique with outdoor baselines using climate averages and evidence based performance ranges. Monthly energy-use data from February to July 2024 and 2025 were used for measuring electricity consumption. The rooftop gardening and rigid polyurethane foam (NPS) had significant savings in terms of electric power consumption through the warm months, specifically to May–July this showed a clear promise to reduce the energy need for cooling more than RCC roof. Results indicate that roof-top gardening results in larger peak reductions (≈2–5 °C at midday-dependent on month) in indoor temperature and a reduction of indoor relative humidity during hot hours by approximately 1–3% compared with the RCC roof condition. Total electricity consumption decreased from 180 kWh to 166 kWh between the monitoring periods, representing an observed reduction of approximately 7.8%. Based on energy analysis, the projected simple payback periods were approximately 9.47 years for rooftop gardening and 9.67 years for PUF insulation. Rooftop gardening demonstrated greater peak-temperature reduction and projected thermal benefits, while PUF offered lower initial cost and maintenance requirements. The report includes hourly datasets (Feb–July), comparative tables, and charts to support retrofit decision‑making in similar tropical–subtropical contexts.

https://doi.org/10.36937/ben.2026.41171

Fadi Hasan Taner Tekin

In recent years, considerable attention has been devoted to developing sustainable, cost-effective, and environmentally friendly composites for the removal of organic pollutants from aqueous media. Among semiconductor photocatalysts, BiVO4 has attracted significant interest due to its favorable physicochemical properties and potential application in photocatalytic processes. In this study, BiVO4/WO3 composite doped with cobalt-containing species loadings were synthesized via a hydrothermal method to investigate the effect of cobalt-containing species addition on methylene blue (MB) degradation. The morphological and crystalline structures of the synthesized composites were characterized using scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS) and X-ray diffraction (XRD). EDS analysis confirmed the presence of oxygen, bismuth, vanadium, tungsten, and cobalt within the composite structure. Photocatalytic degradation experiments were performed under UV-C irradiation (254 nm, 44 W m-2) using methylene blue as a model pollutant. Among the samples examined, the BiVO4/WO3 photocatalyst containing 0.5% by weight Co-dopant showed the highest degradation efficiency, achieving 61% MB removal after 120 minutes. In comparison, BiVO4/WO3/1 wt% Co-dopant, BiVO4/WO3, BiVO4/WO3/1.5 wt% Co-dopant, and BiVO4/WO3/2wt% Co-dopant showed removal efficiencies of 45%, 35%, 28%, and 6%, respectively. The results suggest that moderate loading of cobalt-containing species is associated with enhanced photocatalytic degradation performance under the conditions investigated, whereas excessive loading adversely affects MB removal efficiency.

https://doi.org/10.36937/ben.2026.41149

Eda Keleş Güner Abdulkadir Özer

Nickel borate (Ni₃(BO₃)₂) has attracted considerable attention due to its promising applications in catalysis, electrochemical energy storage, magnetic materials, and ceramic technologies. Nickel borate was synthesized via a co-precipitation method using nickel chloride hexahydrate, boric acid as precursor materials, and Cetyltrimethylammonium bromide (CTAB), N-dodecyl-N,N-dimethyl-3-ammoniopropanesulfonate (SB12), Sodium dodecyl sulfate (SDS) as surfactants. The precipitated product was calcined at 800°C to obtain crystalline nickel borate. The synthesized material was characterized using XRD and SEM. TGA analysis confirmed the formation of crystalline nickel borate, while FTIR spectra verified the presence of borate groups. The XRD analysis confirmed the formation of orthorhombic Ni3(BO3)2 after calcination at 800°C. SEM observations revealed that SB12 promoted larger spherical crystallites whereas SDS produced finer particles with severe agglomeration. FTIR results show that the type of surfactant affects the binding environment and surface chemistry of the synthesized nickel borate materials, while common B–O related bands confirm that the basic borate structure is preserved in all three samples. These FTIR observations are also consistent with the expected surfactant-dependent differences in morphology and crystal structure observed by SEM and XRD. TG-DTA analysis indicated crystallization around 700°C and demonstrated the highest thermal stability for the CTAB-derived sample. The properties of nickel borate are strongly influenced particularly by the use of surfactant during particle formation. The findings suggest that appropriate surfactant selection can significantly enhance the structural and functional properties of nickel borate materials.

https://doi.org/10.36937/ben.2026.41165