Volume 18 Issue 2

Seeds from Cassia obtusifolia L., i.e. Semen cassiae (SC) were evaluated as environmentally friendly filler particles for artificial turf. The goal was to avoid unwanted germination problems of SC under wet conditions. This work evaluated the influence of different pretreatments on the germination rate and performance of SC. After the combination of polishing and dry heat (90 °C, 72 h) treatment, the germination rate of SC decreased to 0% and the activation energy increased to 216 kJ/mol. Compared with the untreated SC, the thermal stability of SC improved, with an initial degradation temperature of 214 °C and a pyrolysis residue of 31.9%. Additionally, the resilience and the water absorption of SC as a filler material increased to 4.13% and 169%, respectively. This study provides an effective pretreatment method for the solution of germination problem and the performance improvement of SC. This makes the pretreated SC a prospective candidate as an environmentally protective granular filling material.

In traditional pulping, black liquor is burned in an alkali recovery system to produce energy. According to the integrated forest biorefinery (IFBR) concept, hemicellulose is partially pre-extracted prior to pulp production to generate value-added products. Corn stalks have a remarkable carbohydrate content (75% w/w), and thus were examined in this study in terms of the IFBR concept. The hemicelluloses were pre-extracted with hot water (90, 120, 135, and 150 °C), NaOH, and NaOH + NaBH₄ (50, 70, and 90 °C) for 4 h. NaOH charges of 16.7, 26.7, and 33.3% were explored. The extracts were utilized to produce bioethanol and biodegradable films, and papermaking pulps were produced from the solid fractions. Differences among groups were identified via analysis of variance, and the Duncan’s test was applied to determine those differences that were significant. The results showed that the alkaline pre-extraction (26.7% NaOH at 50 °C) removed 35.6% of the xylose from the stalk structure. The liquid fraction collected from the hot water pre-extraction at 150 °C gave a 14.7% (g/100 g soluble material) yield of bioethanol. Moreover, the theoretical ethanol yield was calculated as 89.4%. The addition of gluten and nanocellulose to the xylan enabled the production of high-quality biodegradable films. Furthermore, the pulps produced from the hot water pre-extracted solid fractions were comparable in yield and pulp properties to the control soda pulp.

Building materials that are bio-based and produced from waste streams have a substantial effect on the carbon footprint of buildings. In this study, the authors prepared fully bio-based sound absorbers from waste wood and other cellulosic materials. Cutter shavings (CSs), softwood pulp, and cellulose powder (CP) were used as raw materials to prepare sound absorber samples using the foam-forming technique. The fully bio-based sound absorbers prepared were mechanically stable. However, an increase in CSs content decreased their mechanical properties, and samples with high CSs content became difficult to handle. The CP increased the mechanical properties, but it did not affect the sound absorption of the samples. The sound absorption properties of these fully bio-based materials could be tuned by carefully selecting CSs and fiber contents and adjusting the thickness of the material. Greater CSs content decreased the sound absorption properties of the materials. This decrease was mainly due to an increase in the average pore size, leading to poorer sound energy dissipation by visco-thermal effects.

The space-time structure of a teak wood specific gravity (SG) dataset was analyzed using a mixed-effects model. Spatial correlation increased in space, a phenomenon attributable to the maturation of apical meristems, while the temporal correlation of vascular meristems decreased over time. The decay of temporal correlation over time was attributed to the diminishing crown effect on the later formed wood further away from the pith, morphogen gradient, and probably changing microenvironmental conditions. The Kronecker product was used to collect spatiotemporal data on the intricate dynamic process of the evolution of the apical and lateral meristems. The results showed that height and relative radial distance (RRD) (i.e., the flow of time with wood formation) were statistically significant factors, with their interaction showing no significance. The results confirm the usefulness of using the space-time approach to elucidate the interaction between the apical and lateral meristems, two major inherent biological systems that control tree growth and wood formation dynamics. To understand the origins of patterns that vary both temporally and spatially in the tree, future work should describe the variation of SG within the tree due to increasing height (space) and diameter (age) as a matrix; then the correlation function can be modelled.

In this study, the impregnation of a 3% solution of a mixture of medicinal aromatic plant extract, borax, and ferula plant extract on wood of eastern spruce (Picea orientalis L. (Link)) and mahogany were carried out and the changes in the anatomical structure of the impregnated wood were determined. Through obtaining extracts of various medicinal aromatic plants (ferula) and dual treatment with borax, the anatomical properties of wood material were examined and the related adhesion scale was determined. The highest retention (retention) was in mahogany wood borax (1.86%), and the lowest retention was again in mahogany wood ferula extract (0.31%). Both wood types demonstrated improved outcomes in comparison to the control sample when the air-dry and fully-dry specific gravity changes were investigated. The maximum air-dried specific gravity value was found in mahogany at 3% borax and ferula + borax (0.56 g/cm³), and the lowest at 3% ferula and borax (0.37 g/cm³). Mahogany wood with 3% borax had the greatest full dry specific gravity value (0.54 g/cm³), and spruce wood with 3% ferula and ferula + borax had the lowest (0.35 g/cm³). There was no retention in the tracheid and trachea cells that perform the transmission function. Because the sapphire cells are the cells that act as storage, adhesion has occurred in these cells.

5-Ethoxymethylfurfural (EMF) can be considered as a potential biofuel because of its excellent combustion properties, such as high energy density and low carbon smoke emissions. In this study, Ultra-stable Y (USY) zeolite was modified with NH₄H₂PO₄ and then used as an efficient solid catalyst for the catalytic synthesis of EMF via ethanolysis of glucose First, the NH₄H₂PO₄-modified USY was characterized by FT-IR, XRD, BET, and NH₃-TPD. The effect of reaction temperature, reaction time, substrate concentration, and catalyst loading on the yield of EMF was investigated. The P0.2-USY optimal EMF yield was 39.6 mol%, which increased by 20.7% compared to USY, and still had better activity after being reused for 5 cycles. Moreover, the pseudo-homogeneous first-order kinetics model was developed to elucidate the kinetics of EMF formation from glucose, and the kinetics results showed that the activation energy of EMF formation (64.2 kJ⋅mol^-1) was lower than that of humins formation (73.2 kJ⋅mol^-1). Finally, the ethanolysis pathway was proposed based on the product distribution.

Efforts to minimize negative effects on the environment are manifested in the hospitality sector in the form of integrated application of elements of sustainable business, circular economy, bioeconomy, and environmental management. Those who run accommodation facilities are becoming environmentally aware and feel that they should be more involved in sustainable practices and thus contribute to improving the environment both locally and nationally. The main goal of this study is to identify and evaluate the application of selected elements and measures of sustainable business, circular economy, bioeconomy, and environmental management in guesthouses of the Czech Republic. A questionnaire survey (n₁ = 343) was carried out together with a qualitative focus group method (n₂ = 5); the data evaluation was carried out using advanced statistical methods (Tukey HSD test, Kruskal-Wallis test, correspondence analysis). The results showed that a higher classification in the guesthouse is associated with an increasing trend in the number of environmentally friendly operating methods used. Measures related to waste sorting containers (74%) and energy-saving and LED light bulbs (68%) showed the highest values. The results are useful for the practice of national professional associations that support the careful handling of resources and thereby influence the entire hospitality sector.

Effects of pre-treating pine kraft pulp kappa number 31.5 with peracetic acid (Paa) (0.33% and 0.66% as active oxygen based on oven-dried pulp) before O₂-delignification were studied relative to the consumption of chlorine dioxide in a subsequent Elemental Chlorine Free (ECF) bleaching process. The study showed that such pre-treatment is an effective way to extend the delignification of the pine pulp and to reduce the consumption of chlorine dioxide required to bleach the pulp to a brightness of 87%. The reduction in chlorine dioxide required to bleach the pine pulp depended on the amount of Paa used for pre-treatment. Furthermore, the research showed that decreasing the kappa number of the pine pulp to approximately 7.5 units (with Paa pre-treatment and lengthening of O₂-delignification process) caused an over-proportional reduction (by approximately 62.5%) in chlorine dioxide consumption to bleach the pulp to 87% brightness.

Baling cellulosic biomass into round bales is an effective way to reduce the cost of storage and transportation. To improve the quality of bales and reduce the baling energy consumption, this paper introduces the steel roller layout parameters of the round baler into the biomass baling process. Alfalfa was used as an experimental material for five levels pitch value of roller circumferential layout baling experiments. The results showed that the introduction of chamber non-roundness (pitch value of roller circumferential layout) destroyed the formation of the entanglement high density ring cylindrical shell lamination of the outer layer of bales, which was beneficial to the compression of bales core material. When the pitch value was 30 mm, the maximum baling pressure, radial pressure transfer loss, and the baling energy consumption of baler were reduced by 30.4%, 33.4%, and 13.7%, respectively. When the pitch value was 60 mm, the relaxation ratio and radial density difference were reduced by 6.3% and 35.8%, respectively, and the radial density uniformity of alfalfa bale was increased by 32.0%. The experimental results provide a theoretical basis and technical support for the chamber structural optimization design of the round baler.

The Panjian structure is an important longitudinal connecting member of Song Dynasty hall-type buildings in China. To study the lateral force resistance of such structures, a refined finite element model of Song-style hall-type single-room four-column space timber frame containing Panjian structure was established based on the official building code Yingzao Fashi of Song Dynasty. The Panjian and inner E’fang in the lower-ping part, the Panjian in the upper-ping part, and Guazi-gong Panjian and Man-gong Panjian in the roof ridge part were investigated. The model hysteresis curves of all three parts of the longitudinal timber frame were found to be S-shaped, with obvious pinching effect, fuller at both ends and centrosymmetric shape. The Panjian structures in the lower-ping and upper-ping parts, and the Guazi-gong Panjian in the roof ridge part increased the energy dissipation and lateral stiffness of the timber frame. The Man-gong Panjian in the roof ridge part, however, was detrimental to the lateral resistance of the structure. Throughout the test, the Panjian structures were relatively intact, with large plastic damage occurring at both ends of the E’fang. For the repair and testing of similar ancient buildings, some reference suggestions are provided.