Volume 21 Issue 3

Environmental concerns have been highlighted by the overuse of synthetic fibres and polymers in foam products because of their limited sustainability and low biodegradability. This study investigated the potential application of bamboo fibre (BF), a natural, renewable, and environmentally friendly material, as a reinforcement for polyurethane foam (PUF) to address this issue. This research aimed to evaluate the effects of different bamboo fibre loadings, ranging from 5 to 20 wt%, on the thermal, mechanical, and physical properties of BF/PUF composites. Composite samples were fabricated with different fibre loadings and analysed for thermal stability using thermogravimetric analysis (TGA), flexural and compression strength, and physical evaluations. The results showed that BF reinforcement improved the thermal stability of PUF, with BF5 and BF10 composites exhibiting the highest flexural strength (0.199 kPa at 10 wt%) and compression strength (0.223 kPa at 5 wt%), although higher fibre content reduced mechanical properties. In addition, the BF5 composites demonstrated the lowest percentage of moisture absorption (4.78%), thickness swelling (4.25%), and water absorption (49.7%), indicating better dimensional stability. With all factors, adding the bamboo fibre into PUF enhanced the eco-performance of polyurethane foams, making them promising candidates for environmentally friendly applications such as insulation, cushioning, and packaging.

Augmented reality (AR) interfaces for custom wood-veneered cabinets require accurate requirement elicitation that accounts for the anisotropic optical properties of natural veneer. However, existing approaches lack a systematic pipeline linking large-scale user feedback to interface specifications. This paper presents a data-driven requirement mining framework that couples BERTopic semantic topic modeling with user mental model construction and cross-validates the two through a Jaccard-based semantic mapping coefficient (SMC). Applying the framework to a corpus of 3163 multi-source semantic units, the pipeline consolidated 18 initial clusters into four core requirement themes through hierarchical merging (CV coherence improved from 0.421 to 0.573) and translated them into a three-tier priority specification (P0/P1/P2) via a Comprehensive Priority Index. A high-fidelity AR prototype incorporating physically based anisotropic veneer rendering was evaluated with 60 participants across four user groups. The prototype achieved a System Usability Scale score of 82.5 (SD = 4.4) with no significant inter-group differences (F(3, 56) = 1.24, p = 0.303), confirming that the requirement-driven design pipeline can yield robust cross-group usability.

In recent years, the increasing demand for sustainable and renewable materials has intensified interest in biomass resources capable of supporting green processing and circular bioeconomy strategies. Among these, Opuntia spp. (commonly known as nopal or prickly pear cactus) has emerged as a promising biomass resource due to its adaptability to arid environments and its rich and diverse chemical composition. This review aims to provide a comprehensive and integrated analysis of Opuntia spp. biomass, focusing on its chemical composition, extraction and processing technologies, and its potential for the development of bioproducts and biomaterials. One of the key aspects addressed is the comparison between conventional and environmentally friendly extraction approaches, considering their efficiency, limitations, and suitability for recovering important fractions such as mucilage, structural polysaccharides, and bioactive compounds. This review evaluates the utilization of these fractions in food systems, biodegradable materials, hydrogels, composite materials, and environmental remediation, with an emphasis on their functional attributes and technological potential. Sustainability is considered from a biorefinery perspective, focusing on the efficient use of biomass and the mitigation of environmental impacts. This work gives a critical analysis of recent progress and highlights mayor challenges concerning process standardization, scalability and material properties. The findings support the potential of Opuntia spp. as a versatile platform for sustainable materials and point to future research needed for industrial implementation.

The most notable characteristic of the yueqin is its high frets. A PicoScope oscilloscope and related data recorder were used to record the sound signals in real time. Fast Fourier Transform (FFT) analysis, and voltage-based triggering were all made possible by PicoScope software. The PicoScope recorded the fundamental frequency for open strings 1, 2, 3, and 4 as 222 Hz (A3=220), 146 Hz (D3=146), 222 Hz (A3=220), and 292 Hz (D4=294), respectively. The strings 1, 2, 3, and 4 were perceived as A3, D3, A2, and D2, respectively. The measured frequencies were not in accordance with perceived notes due to the phenomenon in which the listener claimed to recognize the note D2 when they actually heard D4. This is the well-known phenomenon of the ‘missing fundamental’. The frequency between the frets follows a musical system that might change depending on the tuning and regional tradition. The running note for open string 1 is A3 and fret 1, 2, 3, 6, 7, 9, 11,13, 14, 16, 18, 20, 22 and 23 are B3, C4, D4, E4, F4, G4, A4, B4, C5, D5, E5, F5, G5, A5 whereas fret 4, 5, 8, 10, 12, 15, 17, 19, and 21 have the notes D4↑, D4#↓, F4#↓, G4#↑, A4#↓, C5#↑, D5↑, F5↓, and F5#↑ respectively.

Plastic waste is one of the most concerning issues for the environment in the world. Many researchers are seeking sustainable solutions by replacing petroleum-based plastic with bio-based plastic. Bioplastic is synthesized from natural resources, and it can degrade in different ecosystems. Therefore, it could serve as alternative to combat the harmful impacts of conventional plastic. This review explores different bio-based polymers such as polylactic acid (PLA), polyhydroxyalkanoates (PHA), polybutylene succinate (PBS), starch blends (SB), and cellulose-based bioplastics (CB). These polymers can be used for many industrial applications, including agriculture, automobiles, textiles, packaging, and medical. To give insight into the procedure of bioplastic manufacture, various processes are analyzed in this review, including the solvent casting technique, extrusion techniques, injection molding, and 3D printing. The products of bioplastics such as micro-nano plastic, monomers, and oligomers released after degradation are critically analyzed and the toxicity of bioplastic on different ecosystems has been discussed. A research gap was also identified, as most toxicological studies of bioplastic do not include the LC₅₀/LD₅₀ threshold.

This study investigated the effects of loading point distance, grain direction, and crack depth ratio on the load-bearing capacity of longitudinally cracked timber beams. Pinus sylvestris var. mongolica was selected for specimen preparation, and fracture tests were conducted under three loading configurations: three-point bending, four-point bending with a large loading-point distance, and four-point bending with a small loading-point distance. Specimens with grain directions of T(tangential), R(radial),and TR(tangential-radial) in crosssection were used. A total of 720 defect-free specimens and 1,200 specimens containing a longitudinal crack at the middle-height layer were tested. Three coefficients, namely load-bearing capacity coefficient, load-bearing capacity degradation coefficient, and crack hazard effect coefficient, were defined to quantify the crack influence. The results showed that T-specimens had the highest load-bearing capacity, followed by R-specimens, and TR-specimens were the lowest. The increase of loading-point distance in four-point bending aggravates the degradation of load-bearing capacity. There exists a critical crack depth, and the load-bearing capacity decreases significantly only when the crack depth exceeds the critical value; the larger the loading point distance, the smaller the critical crack depth. These findings offer a scientific basis for damage assessment and safety control of timber structures with longitudinal cracks.

Microfibrillated cellulose (MFC) is a bio-based material produced by disintegrating cellulose fibers into microscale fibrillar components. Owing to its biodegradability, renewable origin, and favorable oxygen and oil barrier as well as film-forming properties, MFC has potential for sustainable packaging applications. However, its broader utilization is limited by the high energy consumption associated with the fibrillation process. One approach to improving resource efficiency is to collect and reuse any off-specification MFC films, such as products having incorrect grammage, the presence of wrinkles, or excess material related to trimming. In this study, the redispersion of MFC films using an ultrasound-assisted disintegration method was investigated, with focus on film properties and energy efficiency. The results showed that ultrasound-enhanced treatment during recycling improved the UV barrier performance of MFC films, reducing UV transmittance by 24 to 35% compared to unrecycled reference films. Longer ultrasonication time increased the visible light transmittance 14% compared to the reference film with same thickness. In addition, tensile properties were enhanced, with increases of 36% in strain at break and 41% in tensile index. The findings demonstrate that recycling of MFC films does not compromise, and may even improve, mechanical and barrier properties, while enabling notable savings in raw materials, energy, and costs.

Wood is increasingly appreciated not only for its aesthetic and tactile qualities but also for the sense of naturalness and sustainability it conveys. Grounded in the Stimulus–Organism–Response (S-O-R) framework, this study examines the association between environmental consciousness and impulsive buying behavior in interior environments characterized by wooden design elements. The model is employed as a conceptual lens to interpret how sustainability-related cues may be associated with cognitive and behavioral responses. Data were collected from 420 participants living in Batman, Türkiye, who regularly visit cafés, stores, and shopping areas designed with prominent wooden features. A structured questionnaire including validated scales for environmental consciousness and impulsive buying was administered. Correlation and multiple regression analyses were conducted to explore the relationships between the constructs. The results revealed a positive and statistically significant association between environmental consciousness and impulsive buying tendencies. The findings extend the applicability of the S-O-R perspective to sustainable material contexts. Wooden interiors can be interpreted as aesthetic and psychological stimuli that may connect environmental awareness with spontaneous purchasing tendencies. This duality offers valuable insights for designers, retailers, and sustainability researchers, demonstrating how natural materials can encourage both ecological reflection and emotional activation in everyday consumer behavior.

Bamboo is a green and renewable building material having high economic value, high yield, and good mechanical properties. In this study, a total of 160 bamboo samples were tested, and the transverse stress-strain curves and the characteristic values of bamboo were analyzed. The relationship between the thickness, diameter, transverse compressive strength, and transverse compressive elastic modulus of bamboo and with its height was established. The transverse stress-strain constitutive relationship of bamboo was proposed. The results showed that the transverse compressive failure modes of bamboo mainly include bending failure and baroclinic failure. The transverse compressive stress-strain curves of bamboo can be divided into elastic stage, elastoplastic stage, and failure stage. Bamboo wall thickness, diameter, transverse compressive strength, and transverse compressive elastic modulus have strong correlation with height. Based on the stress-strain curves of normalized processing, a transverse compressive stress-strain constitutive model of bamboo achieved high fitting goodness.

This study investigates the acoustic, tribological, and microstructural behavior of hybrid epoxy composites reinforced with Calotropis powder, milkweed fiber, and banana stem fiber. Six composite formulations (S1–S6) were fabricated by maintaining a constant epoxy content of 60 wt% while varying the proportions of Calotropis powder, milkweed fiber, and banana stem fiber. The optimized samples, S4 and S5, contained 10 wt% Calotropis powder with different fiber proportions. The acoustic performance was evaluated through sound absorption coefficient and noise reduction coefficient (NRC), while tribological behavior was assessed using dry sliding wear rate and coefficient of friction (COF). Scanning electron microscopy (SEM) was employed to examine the fracture surfaces and wear mechanisms of the developed composites. The results showed that the presence of Calotropis powder improved interfacial interaction and internal porosity, which enhanced the acoustic performance of the composites. Sample S4 (10 wt% Calotropis powder, 15 wt% milkweed fiber, and 15 wt% banana stem fiber) exhibited the highest sound absorption coefficient (0.45) and NRC (0.41). In contrast, tribological performance improved with higher banana stem fiber content, with sample S5 (10 wt% Calotropis powder, 10 wt% milkweed fiber, and 20 wt% banana stem fiber) showing the lowest wear rate (2.7 × 10⁻⁶ mm³/N·m) and COF (0.47). SEM observations confirmed good fiber dispersion and improved interfacial bonding in the optimized composites, indicating their suitability for acoustic damping and wear-resistant applications.