The urgent need for sustainable water treatment solutions has driven global scientific efforts toward developing novel materials. Biochar, a low-cost material produced from biomass waste, represents a promising and versatile adsorbent class. In this study, acid-treated peanut shell biochar (PS-BC) was synthesized and evaluated for the removal of the methyl orange (MO) dye from aqueous solution. Characterization via Fourier Transform Infrared Spectroscopy (FT-IR) confirmed the presence of carbonaceous groups, such as C=O, C-O, C=C and derived phosphoric groups, such as P=O. Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDS) revealed a mesoporous and macroporous structure, while X-ray Diffraction (XRD) indicated a predominantly amorphous material containing amorphous SiO₂ phases. The adsorption was followed by monitoring 464 nm band of MO in UV-Vis spectroscopy, and the adsorbent achieved a maximum removal of above 89% of MO within a 60-minute experiment. The adsorption kinetics were analysed in pseudo-first and pseudo-second models, which the adsorption was described better by the pseudo-first-order model. Also, adsorption isotherms (Langmuir, Freundlich and Temkin) were studied, and the equilibrium data closely fit the Langmuir isotherm model, pointing to monolayer adsorption onto a homogeneous surface. The FT-IR analysis of post-adsorbed PS-BC confirmed bands associated to MO, such as N=N, SO₃^- and change in aromatic C=C, indicating the possible adsorption pathways. These results confirm the successful application of the acid-treated PS-BC as an efficient and eco-friendly adsorbent for organic pollutant removal from water.

In response to the growing demand for sustainable technologies for wastewater treatment, this study reports the green synthesis of Ag?O-doped TiO? nanoparticles using Salix babylonica bark extract as a natural reducing and stabilizing agent. Although several plant extracts have been explored for the green synthesis of photocatalysts, the use of Salix babylonica biomass for the simultaneous synthesis and Ag?O doping of TiO? nanoparticles remains scarcely investigated. The proposed synthesis route eliminates the need for hazardous chemicals and provides an environmentally friendly alternative for the production of photocatalytic materials. The synthesized samples, containing 0, 0.5, and 1 wt% Ag?O, were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and UV–Vis spectroscopy. The results confirmed the formation of predominantly anatase-phase TiO? and the successful incorporation of silver species without altering the crystalline structure of the oxide matrix. Ag incorporation promoted changes in the morphological and optical properties of TiO?, favoring improved charge separation and enhanced light utilization. Photocatalytic activity was evaluated through the degradation of methylene blue under irradiation. The Ag?O-doped samples exhibited superior performance compared with undoped TiO?, with the 1 wt% Ag?O sample showing the highest degradation efficiency. This improvement is attributed to the formation of Ag?O/TiO? heterojunctions, which facilitate electron–hole separation and increase the generation of reactive oxygen species responsible for pollutant degradation. Overall, the results demonstrate that the proposed green synthesis strategy is a simple, low-cost, and sustainable approach for producing efficient photocatalysts with potential application in environmental remediation and wastewater treatment.

Cutting force is a key indicator that reflects the mechanical interaction between the cutting tool and the workpiece during machining. It directly influences energy consumption, tool wear, process stability, and machined surface quality. As modern manufacturing increasingly demands efficient, flexible, and sustainable production systems, the development of adaptive, real-time, and cost-effective cutting force measurement technologies has become essential. Previous review studies have primarily focused on cutting force modelling and commercial dynamometer systems, while limited attention has been given to the integration of low-cost sensors, microcontrollers, Internet of Things (IoT) technologies, and smart manufacturing applications. This review aims to evaluate recent developments in sensor- and microcontroller-based cutting force measurement systems and their potential integration within Industry 4.0 environments. The review synthesizes more than 230 references, primarily published between 2020 and 2026, together with selected earlier studies that provide important theoretical and technological foundations. Four main aspects are discussed: (1) theoretical foundations of cutting force, (2) sensor technologies and measurement system architectures, (3) modelling and data analysis methods, and (4) challenges and future development trends. The findings indicate that load cell and strain gauge sensors provide economical and practical solutions for long-term monitoring, whereas piezoelectric sensors remain the preferred option for high-frequency dynamic measurements due to their superior sensitivity and bandwidth. Furthermore, the integration of microcontrollers, IoT connectivity, machine learning, and digital twin technologies is accelerating the development of intelligent machining systems for smart and sustainable manufacturing.

The growing demand for sustainable construction materials has spurred research into cement-based composites that can contribute to environmental remediation. In this context, photocatalytic materials containing titanium dioxide (TiO?) have attracted considerable attention due to their ability to degrade organic pollutants under ultraviolet radiation. This study aimed to develop and evaluate TiO?-modified rendering mortars with enhanced photocatalytic performance for potential application in building facades and surface coatings. Mortar mixtures were produced with 0%, 2%, 6%, and 10% TiO?, expressed as a percentage of cement mass. The materials were characterized through ultraviolet–visible (UV–Vis) spectroscopy, scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM/EDS), and X-ray diffraction (XRD). Photocatalytic activity was assessed using methylene blue degradation tests under UV irradiation. The results demonstrated that TiO? incorporation influenced the methylene blue removal behavior of the mortars under UV irradiation. Among the TiO?-modified formulations, the mortar containing 10 wt.% TiO? exhibited the highest overall removal efficiency. Because no adsorption–desorption equilibrium was established before irradiation, the measured dye removal represents the combined effects of adsorption and photocatalytic degradation. Microstructural analyses confirmed the presence and distribution of TiO? particles within the cementitious matrix and indicated changes associated with increasing nanoparticle content. Although higher TiO? additions enhanced photocatalytic performance, they also reduced the workability of the fresh mortars. Overall, the findings demonstrate the potential of TiO?-modified rendering mortars as multifunctional construction materials capable of combining conventional protective functions with photocatalytic properties for environmental remediation applications.

The mechanical, physical, and thermal properties of composite friction material are key parameters influencing both the direct performance of automotive brake systems and secondary phenomena, such as spark and flame generation during braking. These properties are strongly affected by the composition and interaction of the raw materials used in the formulation. In this study, a novel friction material for automotive brake pads was developed with the aim of improving tribological and physical performance while reducing spark and flame generation. Oxidized polyacrylonitrile (PAN) fiber was incorporated into a reference formulation at volume ratios of 1:1, 1:2, and 1:4 relative to the aramid fiber conventionally used. In addition, zinc borate was introduced at 5, 10, and 15 vol%, replacing part of the conventional filler content. A hybrid formulation containing both PAN fiber and zinc borate was also evaluated to investigate possible synergistic effects. The samples were characterized by scanning electron microscopy, Gogan hardness, specific gravity, cold and hot compressibility, and thermal conductivity tests. Spark and flame generation tests were also performed under simulated braking conditions. The results showed that the incorporation of PAN fiber reduced material stiffness, whereas zinc borate increased it; their combined use resulted in a more balanced mechanical response. Compressibility and porosity were also affected by the additives, with noticeable variations among the formulations. Internal shear strength was significantly influenced, with one hybrid formulation showing a marked increase. In particular, the hybrid formulation exhibited a balanced performance, with reduced spark generation, indicating its potential for automotive brake pad applications.

Steel arch bridges are critical transportation infrastructures whose seismic reliability must be rigorously evaluated, particularly in high-seismicity regions such as Indonesia. Despite the widespread application of performance-based seismic assessment, probabilistic evaluations of existing steel arch bridges using Incremental Dynamic Analysis (IDA) remain limited. This study investigates the seismic performance and reliability of the Rumbai Jaya Bridge using Incremental Dynamic Analysis (IDA) within the Performance-Based Earthquake Engineering (PBEE) approach. A three-dimensional finite element model was subjected to twelve spectrally matched ground-motion records representing multiple seismic source mechanisms, with excitation intensities progressively scaled from 0.1g to 1.0g. Structural performance was quantified through drift-based limit states and seismic fragility curves following the NCHRP Synthesis 440 criteria. The analytical model exhibited a fundamental period of 0.48 s dominated by transverse vibration, while demand-to-capacity ratios of 0.40, 0.61, and 0.39 for bending moment, shear, and axial force, respectively, confirmed adequate structural capacity prior to seismic excitation. The IDA results revealed considerable record-to-record variability, with the Tohoku ground motion producing the most critical response, reaching a maximum drift of 12.33%. Nevertheless, the mean structural response remained below the Near Collapse threshold, exhibiting an average drift of only 4.64% at the maximum intensity of 1.0g. Fragility analysis further demonstrated that, under the site-specific design peak ground acceleration of 0.151g, the probabilities of exceeding the Operational and Collapse limit states were only 11.67% and 0.21%, respectively, indicating a substantial seismic safety margin. These findings demonstrate the robustness of the Rumbai Jaya Bridge against design-level earthquakes and highlight the effectiveness of IDA-based fragility assessment as a reliable method for performance evaluation and risk-informed management of steel arch bridges in high-seismic regions.