Molybdenum disulfide (MoS₂) is a two-dimensional material with electronic and thermal properties that make it promising for thermoelectric applications. This research presents the results of synthesizing and characterizing MoS₂ thin films obtained by Physical Vapor Deposition (PVD) on silicon dioxide (SiO₂) substrates. Three experimental approaches were explored to assess how changes in deposition conditions affect the material quality. In the first trial, films were formed from commercial MoS? powder in a sulfur-rich (S₂) atmosphere using a PVD tubular furnace. Next, water vapor (H₂O) was added to the process to observe possible improvements in material formation. Finally, silver doping was investigated, introduced during deposition to examine structural and vibrational changes in the MoS₂. The samples were characterized by Optical Microscopy (OM) and Scanning Electron Microscopy (SEM), as well as Energy Dispersive Spectroscopy (EDS), used to evaluate surface morphology and composition. X-ray Diffraction (XRD) was employed to identify the crystalline structure, while Raman Spectroscopy revealed the E₂g¹ and A₁g vibrational modes, associated with the crystallinity of the material. The results indicated that the presence of H2O during deposition favored the growth of more ordered films, with more intense peaks in XRD and Raman spectra. On the other hand, silver doping caused vibrational changes that suggest modifications in the electronic structure of MoS₂.  These findings reinforce the material’s potential for use in thermoelectric devices and demonstrate that variations in synthesis conditions can significantly enhance its structural and functional properties.

Masonry infill walls are commonly used in reinforced concrete (RC) frame buildings for both architectural and environmental reasons.  Although many consider RC systems to be non-structural, their interaction with surrounding frames can have a significant impact on their lateral stiffness, strength, and seismic performance. This can lead to stiffness issues and soft-story failures during earthquakes. This study looks at the structural function of masonry infills. It compares the experimental load-displacement backbone curve of an infilled RC frame with numerical predictions from four well-known Equivalent Diagonal Strut (EDS) models: Holmes, Mainstone, Liau and Kwan, and Paulay and Priestley. We looked at how well the models performed for both serviceability (initial stiffness) and ultimate limit states (peak lateral strength). The findings demonstrate a definite trade-off in predictive accuracy. With a mean stiffness ratio of 1.38, the Mainstone model yielded the most accurate estimate of elastic stiffness. The Holmes and Liau and Kwan models, on the other hand, significantly overestimated stiffness (ratio = 1.92). All models were conservative (ratios < 1.0) for peak strength. Holmes and Liau and Kwan produced the closest predictions (ratio = 0.84), while Mainstone was the most conservative (ratio = 0.80). These results indicate that the best choice of EDS model depends on the design goal: Mainstone is better for serviceability assessments, while Holmes and Liau and Kwan provide more realistic predictions for ultimate lateral capacity.

The role of borax as a setting-time modifier in Class F fly ash-based geopolymer concrete is not yet well understood. Particularly with respect to its effects on mechanical and fresh properties. This research investigates the influence of borax incorporation on the properties of geopolymer concrete. Class F fly ash from the Tanjung Jati B power plant was used. Borax was added at fly ash weights of about 0%, 5%, 10%, and 15%. Tests were arranged to observe setting time, compressive strength, elastic modulus, and slump value to assess mechanical performance and workability. The results represent, borax effectively prolongs the initial and final setting times, with greater effectiveness in Class F fly ash (low CaO) than in Class C fly ash (high CaO). The addition of 5% borax resulted in a higher compressive strength and modulus of elasticity. However, higher borax dosages reduced mechanical properties by inhibiting geopolymerization. An increase in borax content reduced slump values, reflecting lower workability due to higher mixture viscosity. While borax can effectively regulate setting time in Class F fly ash–based geopolymer concrete, its dosage must be carefully optimized to prevent negative effects on strength and fresh concrete performance.