BioResources (E-Journal)
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Analytical Equations for Predicting Effective Thermal Conductivity in Laminated Wood Composites
No full textThis paper presents an analytical modeling approach to predict the effective in-plane and out-of-plane thermal conductivities of laminated wood composite products such as Cross-Laminated Timber (CLT). Considering wood’s orthotropic nature, having models that could be used to estimate the effective thermal conductivity properties of laminated wood products in various directions becomes essential for understanding the coupling between mechanical and thermal properties, as well as predicting the dimensional stability of large wood composite panels. For this purpose, analytical thermal conductivity equations were derived in three orthogonal directions, considering different properties of wood along its orthotropic directions, following Fourier’s Law. The derived equations were then applied to different CLT panel products and results were compared to assess their accuracy. As CLT panels may be produced without edge gluing, two scenarios were investigated to understand the effect of edge gluing on thermal conductivity of such panels. First, the presence of adhesive between timber layers was ignored (i.e. not edge-glued panels); second, adhesive and its thickness were included. Results demonstrated the reasonable accuracy of the proposed approach in predicting the thermal conductivity of CLT panels made with different gluing methods. The modeling of imperfect bonds and air gaps is also briefly discussed
Determination of the Properties of Medium-Density Fiberboards Produced Using Urea-Formaldehyde Resins Modified with Boron Compounds
No full textEffects of adding different boron compounds to the urea-formaldehyde resin were evaluated relative to the physical, mechanical, and other properties of medium-density fiberboard (MDF). While the chemical addition of boric acid to the urea-formaldehyde resin increased the modulus of rupture and modulus of elasticity values of MDF boards, the physical and chemical additions of other boron compounds decreased those values. While there were no significant decreases in internal bond values, the chemical addition of boric acid and borax decahydrate to urea-formaldehyde resin increased the internal bond values of MDF boards. It was observed that in both types of addition, borax pentahydrate reduced the formaldehyde emission values of MDF boards the most and also reduced the burnt area by up to 30%. When the type of addition of boron compounds to urea-formaldehyde was compared, the addition of boron compounds at the resin formation stage showed better results in the properties of MDF boards than physical addition
Analysis of Wettability and Contact Angle of Sodium Bicarbonate Impregnated Wooden Surfaces
No full textScots pine and spruce wood samples were vacuum impregnated with 3, 5, and 9% sodium bicarbonate solution. Contact angle measurements were made by dropping 0.05 mL of pure water and 3% saltwater solution onto the material’s surface. The surface roughness of each sample was measured, and that of Scots pine control samples was higher than that of spruce samples, but the surface roughness values of spruce wood were higher in the samples impregnated with sodium bicarbonate. When pure water or saltwater solution was dropped onto the samples, it was observed that as the waiting times increased, the contact angle value decreased, the droplet height decreased, and the droplet width increased. It was found that the contact angles were higher in the control samples of both tree species than in the samples of 5% and 7%. The contact angles of 9% impregnation solution, pure water, and salt water were higher than the control samples. As the solution ratio increased on the surfaces impregnated with sodium bicarbonate, the contact angle also increased, and the wettability behavior decreased accordingly. Sodium bicarbonate solution is effectively used in the impregnation process for pine and fir woods, making the materials more resistant to water under outdoor conditions. This solution significantly reduces the risk of deformation of wood by increasing the contact angle and reducing its water absorption properties
Effects of Biogas Slurry Drip Irrigation on Growth Performance of Brassica chinensis L. and Soil Nutrient Dynamics
No full textThe optimal amount of biogas slurry was determined to improve both the yield of Brassica chinensis L. (BL) and soil quality. An experiment was set up with six sets of drip irrigation gradients (1:3 mix of biogas and water) of 12 (BS-1), 15 (BS-2), 18 (BS-3), 21 (BS-4), 24 (BS-5), and 27 (BS-6) L. Each treatment was repeated three times and irrigated eight times. The radius of drip irrigation was 1.2 m, and the dripping speed was 2 L/h. The highest plant height, fresh weight, dry weight, soluble sugar content, and protein content of 25.2 cm, 16.7 g, 1.10 g, 0.61 g/100 g, and 1.90 mg/g, respectively, were obtained under the BS-5 treatment. Soil total nitrogen, available phosphorus, and organic matter content under the BS-4 treatment increased 5.29%, 230.75%, and 1.00%, respectively, compared with those before drip irrigation treatment. The soil available potassium content was highest under the BS-3 treatment and had increased 20.4% compared with that before drip irrigation treatment. The most remarkable influence on the yield and quality of BL was observed when the drip irrigation amount was 24 L. Drip irrigation with 21 L of biogas slurry is conducive to improving soil physical and chemical properties
Comparative Analysis of the Flavonoid Characteristics of Camellia oleifera Flowers in Different Plantations in Guizhou, China
No full textCamellia oleifera is a multipurpose plant resource that contains flavonoids. To explore the differences in the characteristics and metabolic pathways of flavonoids in Camellia oleifera flowers from different plantations, this study compared the differences in the water content, total ash content, ethanol soluble extract, and total flavonoid content of samples from six plantations. Widely targeted flavonoid metabolomics techniques were used to analyze the metabolic characteristics of the different plantations. There were significant differences in total flavonoid content among the different plantations (P < 0.05), with Tianzhu County having the highest total flavonoid content (average value of 13.60 mg/g) and Liping County having the lowest total flavonoid content (average value of 2.39 mg/g). UPLC-MS/MS revealed a total of 13 categories and 758 flavonoid metabolites, among which flavonols, flavonoids, and tannins were the main flavonoid compounds. A total of 266 differentially abundant metabolites were screened via the OPLS-DA model, and KEGG enrichment analysis revealed that the enrichment pathways of differentially abundant metabolites between different plantations were related mainly to the biosynthesis of secondary metabolites, flavonoid biosynthesis, metabolic pathways, etc. This study provides a theoretical reference for the subsequent development and utilization of Camellia oleifera resources, especially in the utilization of Camellia oleifera flower resources
Andrographis paniculata Mediated AuNPs as Anti-Microbial, Antioxidant, Anti-Diabetic Agents and their Efficacy in Wound Healing of Mice
No full textGold nanoparticles (AuNPs) are known to have low toxicity and biocompatibility. Meanwhile, Andrographis paniculata (A. paniculata) is a medicinal plant known for its therapeutic benefits. Traditional methods for the synthesis of AuNPs frequently depend on toxic compounds, which present environmental and health hazards. In this work, A. paniculata was combined with AuNPs to enhance its antimicrobial, antioxidant, and wound healing effects, thereby offering a safer and more effective alternative compared to current available methods. Water-soluble gold metal ions were reduced to neutral metal nanoparticles in the course of reaction with aqueous A. paniculata extract. The biosynthesised AuNPs was examined using UV-Vis, FTIR Spectroscopy, TEM, XRD, SAED Diffraction, EDX, DLS, and zeta potential measurements. AuNPs were incorporated into nonionic surfactant to form a thick, readily spreadable hydrogel. The mixture was found to enhance the wound contraction rate with no skin irritation observed in treated mice. The study demonstrated a simple and environmentally safe approach to produce AuNPs with improved antimicrobial, antioxidant, antidiabetic and wound healing abilities. The AuNPs-PF127 hydrogel is a non-toxic and bio-friendly delivery technology that shows potential in promoting healing of wounds, burns, etc
Properties of Plastic Composites Filled with Giant Reed Flour and Magnesium Oxide Nanoparticles
No full textWood plastic composites (WPCs) were produced from recycled polypropylene (RPP) matrix, giant reed (GR) flour, and magnesium oxide nanoparticles (nano-MgO). The physical, mechanical, and thermal properties were analyzed. Different amounts of GR flour from 10 wt% to 40 wt%, and nano-MgO from 1.0 wt% to 2 wt% were added into the RPP matrix. The water resistance, mechanical, and thermal properties of the injection molded WPCs were determined according to the ISO standards. The bending and tensile modulus of the WPCs were considerably enhanced with the addition of the GR flour up to 40 wt%, while this was found to be maximum at 30 wt% for the bending and tensile strengths. The water absorption of the WPCs increased with the addition of the GR flour, as expected. The results of thermal analysis revealed that the addition of the GR flour increased the thermal stability of the WPCs, especially the degree of crystallization and the melting enthalpies of the RPP matrix, due to the good adhesion between the GR flour and the RPP. The incorporation of the nano-MgO affected adversely the mechanical properties of the WPCs. Lower thermal stability was observed for WPCs containing nano-MgO. The inclusion of 30 wt% GR flour in the RPP matrix gave the best mechanical and thermal properties
Pretreatment Technologies for Lignocellulosic Biomass: Research Progress, Mechanisms, and Prospects
No full textLignocellulose, which consists of cellulose, hemicellulose, and lignin, has very stable properties. Among them, cellulose makes up 30% to 50% of the content, and hemicellulose makes up 20% to 43%. Cellulose and hemicellulose can be converted into fermentable sugar through saccharification, and then into bioresources through fermentation. Pretreatment methods such as high temperature and high pressure, acid and alkali cooking, enzymatic digestion can effectively decompose the lignocellulose structure, remove lignin, increase the porosity of lignocellulose, specific surface area, etc., increase the efficiency of saccharification, and improve the utilization of lignocellulose. Pretreatment is a key stage in the production process of bioresources. However, the pretreatment process produces by-products known as inhibitors such as acetic acid, furfural, and phenols. These inhibitors tend to inhibit the activity of biological enzymes, impede the saccharification of cellulose and hemicellulose, disrupt the integrity of the cell membrane of the fermenting bacteria, lead to mutation of the fermenting bacteria, and result in a decrease in the yield of the bioresource. This paper reviews recent advances in pretreatment methods, analyzes the reasons for the emergence of inhibitors, and summarizes methods to reduce the effects of inhibitors
The ‘Nirai’ Guitar (‘Ichigo ichie’) of Okinawa Japan
No full text‘Nirai’ instrument combined the ‘sanshin’ and guitar. It is a mix of the ‘sanshin’ and the guitar. Instead of using the guitar's tuning, ‘nirai’ is tune like a ‘sanshin’. The ‘nirai’ sound were digitally captured using a PicoScope oscilloscope. The outcomes were subsequently examined utilizing PicoScope software (version 6), emphasizing Fast Fourier Transform FFT. The standard ‘sanshin’ tuning is a fifth, a root, and a fifth, so in the key of C, that would be G, C, G (GCG). When a low C (C) is added in ‘nirai’ it makes the tuning a root, fifth, root, fifth. In this work, the ‘nirai’ is being tune into the key of G, the 4th string of ‘nirai’ can be identified as G2 (100Hz), 3rd string as D3 (147 Hz), 2nd string as G3 (197Hz), and 1st string as D4 (296Hz). String 3 and 4 displayed 25 partials frequencies. String 1 and 2 displayed only 12 and 19 partials frequencies respectively. The partials of the overtones confirmed the typical sound quality of ‘nirai’ guitar. The thin string had less partials compared to the thick string. The partials are all integer number of harmonics with 24th, 17th and 13th harmonics missing in string 4, 3 and 2. All harmonics appear in string 1. Even though the numbers of partials are different, with the sensation of a wooden guitar-like sound, the ‘nirai’ guitar displayed similar timbre from every string
Preparation of Lignin-like Polymers by Dehydrogenation of Lignin Precursors and Structure-activity Relationships of the Resulting Polymers against Live Cancer HepG2 Cells
No full textLignin can be used as a natural anticancer drug because of its potential biological activity and low cytotoxicity. This research focuses on oligomeric dehydrogenation polymers (DHPs) of lignin. The lignin precursor coniferin was used to yield Zulaufverfahren dehydrogenation polymers (ZL-DHPs) and Zutropfverfahren dehydropolymers (ZT-DHPs) catalyzed by mixed enzymes. The 13C-NMR determination showed that the DHPs obtained were similar to natural lignin, and ZL-DHP had a slightly higher β-5 content than ZT-DHP. ZL-DHPs and ZT-DHPs were subjected to organic solvent extraction with different polarities to obtain eight fractions, i.e., ZL-1-ZL-4 and ZT-1-ZT-4. The antitumor activity showed ZL-2 (IC50 181.99 μg/mL) and ZT-2 (IC50 246.76 μg/mL) had significant inhibitory effects. Fractions ZL-2 and ZT-2 were purified through column chromatography using gradient-polarity binary eluent, and 12 purified compounds were obtained, i.e., L1–L6 and T1–T6. The results showed L2 (IC50 33.99 μg/mL) and T1 (IC50 42.08 μg/mL) had relatively high biological activity, respectively. Their structure was characterized using high-resolution mass spectrometry and 13C-NMR, indicating that L2 is a dimer with β-5 linkage (β-5, γ-CH3, and γ'-CH2OH), and T1 is also a dimer with β-5 linkage but different substituents (β-5, γ-CHO, and γ'-COOH).