Volume 19 Issue 3

A smooth and dense surface of the base paper is advantageous when the goal is to apply a liquid coating as a barrier layer. For such a base paper, non-wood fibers derived from wheat straw could be an alternative to wood fibers. In this research paper, wheat straw pulp was refined with different beating levels (up to 600 revolutions) followed by different calendering pressure loads (up to 50 N/mm) to test its influence on mechanical and surface properties. Alkyl ketene dimer (AKD) was used as sizing agent with concentrations up to 0.2 wt% followed by a mineral-based precoating to test its influence on the smoothness. Eucalyptus pulp was chosen as a benchmark. After beating, the initial Schopper-Riegler degrees of 28 °SR increased to 56 °SR. Beating also increased the tensile index from 24 to 49 Nm/g, the burst index from 1.2 to 2.8 kPa·m²/g, and the tear index decreased from 3.3 to 2.8 mN·m²/g. Calendering reduced the initial roughness of 370 mL/min to 30 mL/min. When precoated and calendered again, the value was lowered to 15 mL/min. In summary, wheat straw paper is a relevant alternative to wood-derived base paper to produce barrier papers. Compared to eucalyptus, wheat straw paper showed better smoothness and much lower air permeability indicating excellent suitability for barrier coating.

Morphological measurements of Anatolian chestnut (Castanea sativa Mill.) leaves were done within the borders of Abana district of Kastamonu province. The study was conducted using mixed (oak, beech, hornbeam, black pine, and yellow pine) medium (41% to 70%) and fully closed (71% to 100%) stands. Some leaf parameters, such as leaf blade width, petiole length, leaf blade length, leaf length, distance between lateral veins, teeth width, teeth length, the angle between the leaf base and the petiole, and the angle between the midrib and lateral veins, were measured. Moreover, stomata of the leaves picked up from precise altitudes were observed under a scanning electron microscope. The differences between fibre elevation, fibre wall thickness, elasticity coefficient, rigidity coefficient, Muhlstep rate, and Runkel ratio were found in the wood samples taken from different altitude zones. It was found that altitude did not affect leaf blade width, fibre length, fibre width, felting ratio, and lumen width. However, it was determined that altitude affected other studied characteristics.

Heat treatment of wood is an attractive, environmentally friendly modification, which can change surface visual properties of wood including color and grain, but it is unclear how heat-treated wood is perceived and evaluated compared with untreated wood. In this paper, Chinese fir was heat-treated at 160, 180, 200, or 220 °C for 2 or 4 h. The changes of wood surface color and grain contrast were measured. A subjective questionnaire and eye-tracking technology were used for psychological evaluation. The results showed that changes in the visual properties of heat-treated wood had a significant effect on psychological preference—heat-treated wood was generally more preferred than the untreated, particularly at 200 °C for 4 h. Grain contrast and hue played an important role in the preference for heat-treated wood. The preference gave people the positive psychological impression of warmth, weight, cost, prevalence, and comfort. Eye-tracking analysis showed that Chinese fir heat-treated at about 200 °C with high hue value and clear grain contrast was easier to gain more visual attention. The results would have a high technical reference value for the heat-treated wood in product visual design.

Reverse design and additive manufacturing technologies are fast ways to develop customised products. In this study, furniture protective foot covers were taken as the design object. Using flexible filaments of polylactic acid (PLA) and the development process of reverse design to additive manufacturing, the protective foot covers were designed and manufactured to fit the shape of the chair feet. Furniture protective foot covers have high practical value. They have a certain buffering effect, avoiding the damage caused by the collision of furniture feet with the ground when moving furniture; secondly, they reduce the noise generated by the collision of furniture feet with the ground, creating a quiet and comfortable home environment. According to the finite element simulation results, the maximum stress value of the European-style chair installed with protective foot covers was decreased by 90.8% in the case of vertical fall, which verifies that the protective foot covers have an obvious buffering effect. Noise test results show that the noise of the European-style chair installed with protective foot covers was decreased by 51.0%, which verifies that the protective foot covers have an obvious quieting effect.

A design strategy was developed, based on the KANO model, for health-centric and sustainable e-sports chair products. Specifically, this study investigated the functional requirements of e-sports chairs using interviews and questionnaires to guide their subsequent design. The functional requirements of the e-sports chair were evaluated using the KANO model. In addition, a satisfaction coefficient was introduced to optimize the traditional KANO model and to obtain the functional requirement classification of the e-sports chair. The sensitivity coefficient was used to evaluate whether the e-sports chair functions attract users. The research results show that users have clear functional requirements for e-sports chairs, and there is a significant correlation between satisfaction and sensitivity. Moreover, the adjustability and air permeability of the e-sports chair greatly improves user satisfaction, and the non-difference function can simplify the process by reducing production costs. This research develops a hierarchical model of demand for e-sports chairs and categorizes the results by essential, one-dimensional, attractive, non-differentiated, and sensitivity requirements. Furthermore, the main attributes of user preferences for e-sports chairs are explored, which provides a certain theoretical basis for the subsequent design and production of e-sports chairs.

The primary aim of this research was to explore the feasibility of producing environmentally friendly composite materials by employing diverse hybrid matrices consisting of dammar natural resin, supplemented with small proportions of two synthetic resins: one epoxy and the other acrylic. A blend of paper and chicken feathers served as the reinforcing elements. The fabrication of these composite materials utilized a hand layup technique. Targeted for applications in the furniture industry or interior design, their mechanical properties were assessed through various tests. Specimens were obtained from the manufactured samples and subjected to evaluations for tensile strength, compression, flexure, vibrations, Shore hardness, and water absorption. Results indicated that irrespective of the testing method employed, the mechanical strength properties exhibited a decline with an increase in the percentage of dammar in the hybrid resins, whereas the elasticity properties demonstrated an increase with this percentage.

Some biological materials have bimodulus properties. The elastic modulus in the tensile state is different from its value in the compressive state. The deformation energy decomposition method for bimodulus material can be obtained, and then the deformation energy decompositions of the isotropic and bimodulus frame structure are further realized. On the basis of the quantitative results of the basic deformation energy, the proportions of the areas dominated by shear deformation energy were proposed, which can characterize the ductility of the frame structures. The cases showed that the ratio of the elastic modulus in tensile state to the elastic modulus in compressive state is the important index of bimodulus material, which affects the deformation energy distribution of the bimodulus structure. When the ratio of bimodulus material for the deep beam was 0.2, the proportions of the regions dominated by shear deformation energy for the deep beams located on the 1^st to 3^rd floors were reduced by 10.00%, 7.77%, and 11.11%, respectively. The bimodulus material improved the ductility performance of the frame structure.

Wooden furniture design necessitates the integration of both technological requirements and aesthetic considerations. To guide designers in achieving this balance, this article explores how established design principles, such as proportions and preferred numerical sequences, can inform decision-making for both technological and aesthetic aspects. The goal is to demonstrate how these principles can be integrated with modern CAD tools. In reviewing the scientific literature, this study compiled and compared mathematical and non-mathematical models that support dimensional decision-making. These models included ancient canons (Egyptian, Greek, and Roman) alongside those of Leonardo da Vinci, Palladio, Dürer, Le Corbusier, Zeising, McCallum, and Brock. Additionally, the article examines numeral systems used in modern technology, such as Renard’s series and convenient numbers. It is proposed that designers should experiment with geometric design templates to achieve balanced proportions. All geometric design principles contribute to aesthetics, creativity and effectiveness in design. The literature identifies two groups of dimensional design templates: organic, inspired by the human body or the Fibonacci sequence, and inorganic, based on numerical order. It’s impossible to pinpoint a single “optimal algorithm” to support dimensional decisions in design. Specific geometric design principles serve as valuable tools, not the ultimate answer.

Pine wilt disease is one of the most serious forest diseases that kills pine trees. Most of the nematode-infected pines are fumigated or locally incinerated and are thus not appropriately utilized. This study explored methods to utilize abandoned nematode-infected pines. The chemical compositions of healthy and nematode-infected pines were analyzed, and the neuroprotective effects of phenolic compounds extracted after steam explosion treatment were investigated. In terms of chemical composition, the nematode-infected pine chips suffered more damage from the steam explosion treatment than the healthy pine chips. In addition, the total phenolic compound content showed a clear difference depending on the presence of infection and steam explosion conditions. The maximum total phenolic compound content of extracted ethanol was found when the nematode-infected pine chip was subjected to steam explosion with a severity factor (Ro) of 3.82. The steam exploded pine extract of 10 μg/mL inhibited glutamate-induced early apoptotic cell death compared to cells treated with 10 mM glutamate alone. These results suggested that steam-exploded pine can be used as an effective natural material for neuronal cell protection.

People have long used plants and plant-derived products to treat a wide range of illnesses. In the present work, Tecoma stans flower was extracted using 90% ethanol. Flavonoids and total phenolic constituents of T. stans flower extract were screened, and polyphenolic compounds were assessed using high-performance liquid chromatography (HPLC). Anti-diabetic via α-amylase and α-glucosidase assays, antioxidant via 2,2-diphenyl-1-picryl-hydrazyl-hydrate, ferric reducing antioxidant power, and total antioxidant capacity of T. stans flower extract were assessed. The cytotoxic action for T. stans flower extract was assessed versus WI-38 (human fetal lung fibroblast cells), PC3 (prostate cancer cell line), and SK-OV3 (ovarian cancer cell line). The T. stans extract showed promising in vitro anti-diabetic effect with IC₅₀ = 12.08 ± 0.2 µg/mL and 22.83 ± 0.3 µg/mL for α-amylase and α-glucosidase, respectively. Moreover, T. stans showed good in vitro antioxidant action with IC₅₀= 5.36 ± 0.2 µg/mL for DPPH testing, and the best antitumor impact versus PC3 cells with IC₅₀ = 113.27 ± 1.59 µg/mL. Flow cytometric analysis confirmed the role of T. stans in acceleration in apoptosis of PC3 cells through regulation of oxidative enzymes. These results indicate that the derived materials from T. stans flower have multiple medicinal applications.