Volume 19 Issue 3

This study investigated the material characterization with the fuzzy theory of particleboards bonded by urea formaldehyde with nanofillers including nanofibrillated cellulose (NFC) and titanium dioxide (TiO₂). The density, water absorption, thickness swelling, and mechanical tests (which included flexure and internal bonding strength tests) were considered. The fuzzy sets theory addressed the ambiguity and subjectivity of language using triangular fuzzy numbers to assess the interests of decision maker’s (DMs). The addition of nanofillers slightly decreased water absorption values due to possible good interactions between nanofillers and urea formaldehyde. Thickness swelling ranged from 0.4 to 17.5%, and water absorption ranged from 0.4 to 10.7% compared to the control sample. The physical properties of the samples were generally improved by urea formaldehyde with NFC/TiO₂, and the densities of the test panels were found to be similar. The modulus of rupture of the panels with urea formaldehyde with nanofillers were under the EN 312 standard’s requirements, and the highest flexural strength and flexural modulus of elasticity were 11.1 and 1.3 GPa, respectively. Internal bond values were between 0.55 and 0.89 MPa. According to EDAS method rankings, 2C2T-8 was the best material, followed by 2C1T-8 and 2C-8. The samples coded with Control-4 and Control-8 were the lowest-performing materials.

Psychological and physiological cognitive measurements were combined with Kansei engineering theory to study the shape of the traditional Chinese official-hat chair, a kind of Ming-style chairs, while investigating people’s perceptual cognitive process. This work employed focus groups to obtain 5 groups of representative words and 22 typical samples for evaluation experiments. After data preprocessing, principal component analysis (PCA) was used to extract three main components: “Concise-Ornate”, “Soft-Strong”, and “Elegant-Vulgar”. In terms of component weight calculation, the analytic hierarchy process (AHP) was initially used to calculate the subjective cognitive weight of different components, and then eye-tracking technology was used to assist in calculating the physiological cognitive weight. Finally, combining the subjective and objective weights, the weights of the components were determined as: backrest (41.02%) > stretcher (18.29%) > handrail (11.64%) > top rail (11.14%) > outside stick (8.64%) > inside stick (5.32%) > foot rail (3.95%). The four main components—backrest, stretcher, handrail, and top rail—along with perceptual image evaluations, were selected to establish a multivariate linear regression equation, thereby constructing a mathematical mapping relationship between perceptual image and main design elements. This provides theoretical support for designers in creating different perceptual images.

Ultrasound-assisted extraction for bioactive compound retrieval is a viable alternative to traditional extraction methods. Employing ultrasound-assisted extraction, this study aimed to enhance the scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothia-zoline-6-sulfonic acid) (ABTS), total polyphenol content (TPC), and flavonoid content in Ainsliaea acerifolia (A. acerifolia) through response surface methodology (RSM). Initially, the impact of extraction temperature, time, and ethanol concentration on DPPH scavenging capacity, ABTS, TPC, and flavonoid content was assessed. Optimal conditions for maximizing antioxidant activity and TPC were determined as 78% (v/v) ethanol, 60 °C extraction temperature, and 91 min of extraction time. High-performance liquid chromatography (HPLC) analysis of the optimized extract revealed dicaffeoylquinic acid as the primary polyphenol in A. acerifolia extracts, comprising the majority of phenolic compounds (102.06 mg/g DW). This model enabled the optimization of conditions for phenolic compound extraction with antioxidant properties from A. acerifolia, highlighting its potential as a source of antioxidant compounds for industrial, pharmaceutical, and food applications.

The traditional measurement method for viscoelastic creep strain and mechanical adsorption creep strain has relatively low accuracy, making it difficult to ensure the data accuracy of specimen strain measurements. In this study, 50-mm-thick Pinus sylvestris sawn timber was used as the research object. Along the thickness direction of the test material, the relationship between the free shrinkage coefficient and the moisture content of the test material was studied to optimize the measurement methods of viscoelastic creep strain and mechanical adsorption creep strain during drying process. The results showed that the optimized measurement method for viscoelastic creep strain, which compensates for dimensional change caused by moisture content changes during the creep recovery phase, was applied to different layers in the thickness direction of the test material. The average relative error at the end of the drying stage was reduced 20.1% compared to the traditional method. For the mechanical adsorption creep strain in different layers of the test material’s thickness, the optimized measurement method, based on the free shrinkage size calculated from the free shrinkage coefficient and moisture content, reduced the average relative error 59.1% compared to the traditional method.

The mineralization of inorganic components in paper sludge offers potential for their re-use in various fields. This study synthesized carbonates based on the minerals present in paper sludge and aimed to investigate the control of particle size distribution and particle shape of the synthesized carbonates. First, the physicochemical and thermal properties of paper mill sludge and ash were evaluated using a spectrophotometer, XRF, and TGA. Paper sludge ash was obtained by incinerating the paper sludge, followed by a carbonation reaction using CO₂ gas injection and pH neutralization to produce recycled fillers. The average particle size, crystal lattice structure, and morphology of the recycled fillers were analyzed using a particle size analyzer, XRD, and FE-SEM. The results indicate that the recycled filler produced from coating paper sludge exhibited similar brightness and morphology to conventional paper-based fillers, suggesting its potential to replace commercial PCC (Precipitated Calcium Carbonate). In contrast, the recycled filler manufactured using old corrugated container mill sludge was deemed unsuitable due to its low hydration activity.

Rapid urbanization has led to resource shortages, necessitating sustainable approaches in the building industry. This research proposes a preliminary voxel-based modular-architectural design strategy (VMADS), focusing on reusable “H” blocks for component connections and construction. By integrating computational design and robotic fabrication, VMADS enhances precision and efficiency. The framework addresses discrete building theory, prefabrication, and autonomous architecture, emphasizing wood’s anisotropic nature for structural integrity. Experimental results validated VMADS through digital simulations and physical tests, demonstrating its potential to create sustainable, reconfigurable structures and revolutionize construction practices.

The “Felina 32” variety of industrial hemp (Cannabis sativa L.) is among the most popular cultivated varieties in Lithuania. In 2020 to 2021, the height of the above-ground portion of “Felina 32” ranged from about 1.37 to 2.52 m. In the less favorable year of 2021, 9.8% lower height and 28.5% lower mass plants grew. However, the impact of meteorological conditions on their comparative indicators was not confirmed. Two critical intervals were distinguished, which essentially influence the dynamics of plant growth: crop density of 90 to 150 plants∙m² and plant height of 1.9 m to 1.99 m. Lower crop density results in larger plants, and plants taller than 1.9 m gain mass 2.58 times faster than shorter plants. In addition, industrial hemp of different heights is characterized by differences in the development of morphological parts. This directly affects the physical and chemical properties of biomass. It was determined that when the height of “Felina 32” variety changes, the heat value of biomass increases 0.342 MJ/kg, carbon concentration increases 0.70%, and ash content, sulfur, nitrogen, and chlorine concentrations decreased.

To enhance the scientific rigor of design decisions and develop new rosewood furniture that aligns with user emotions, this study integrates the strengths of the Hesitant Fuzzy Analytic Hierarchy Process (HFAHP) and Hesitant Fuzzy Quality Function Deployment (HFQFD) within the framework of Kansei Engineering (KE). This method accurately translates Consumer Requirements (CRs) into Engineering Characteristics (ECs). First, the KJ Method was used to screen and categorize Kansei words, create product sample images, and deconstruct the form of rosewood furniture using morphological analysis. Second, after collecting valid questionnaires using a 7-point Likert scale, Factor Analysis (FA) was employed to extract three key Kansei factors. Third, HFAHP was utilized to calculate the weights of the Kansei words. Fourth, HFQFD was applied to construct a hesitant fuzzy correlation matrix between CRs and ECs, determining the priority of design elements for rosewood furniture. Finally, using a square table as an example in the design practice, the optimal Scheme No. 9, which highly meets consumer emotional needs and features harmonious form combinations, was selected. This study enhances the emotional value of rosewood furniture, optimizes the design decision-making process, and improves contemporary consumer satisfaction.

Optimization of the extraction procedure was performed to enhance the antioxidant activity and whitening effect of Sasa quelpaertensis Nakai extract using response surface methodology (RSM). The central composite design, a component of RSM, was utilized to optimize and validate the ethanol extract for antioxidant activity and the hot water extract for the whitening effect, respectively. Activities of antioxidant and whitening were determined by DPPH and tyrosinase inhibition assays. The antioxidant activity was notably influenced by ethanol concentration (p = 0.0344) more than other factors. The optimal conditions for the antioxidant effect were 54% ethanol concentration, 52 °C, and 3 h extraction time, yielding an antioxidant activity of 83.65±1.56%. On the other hand, the whitening effect was significantly impacted by ultrasonic irradiation time (p = 0.0175) compared to other factors. The optimal conditions for whitening were 41 °C, 1:19 of sample-to-solvent ratio, and 8 min of ultrasonic irradiation, achieving a tyrosinase inhibition activity of 51.00±1.80%. High-performance liquid chromatography (HPLC) analysis was conducted to identify compounds such as tricin with antioxidant activity and p-coumaric acid, arbutin with whitening effect under the optimized conditions. The results suggest that the optimized extracts from S. quelpaertensis could be utilized as beneficial cosmeceutical materials.

Efficient utilization of wood is inseparable from high-quality drying, and analysis of its free shrinkage performance is essential to optimize the drying process. This study took Pinus sylvestris L. sawn timber (500 mm×200 mm×50 mm) as the research object and adopted the image analysis method to analyze the influence rules of different temperatures and axial positions of the test material on the free dry shrinkage coefficient of each layer of specimens in the thickness direction. The free shrinkage coefficients of each layer in the thickness direction of the test material decreased from the maximum value of the first layer near the tangential direction (0.282%, 0.275%, 0.267%, at 60 °C, 80 °C, and 100 °C, respectively) to the minimum value of the ninth layer near the radial direction (0.248%, 0.249%, 0.227%); except for the near-radial layers, when temperature increased from 60 °C to 100 °C the free shrinkage coefficients of other representative layers decreased with increased temperature. The first layer’s free shrinkage coefficient decreased from 0.282% to 0.267%, and the fifth layer decreased from 0.264% to 0.243%. The difference of free shrinkage coefficients between corresponding layers at different axial positions of the test material was less than 0.017%, and the size stability of the corresponding layers at axial positions was high.