The effects of brown-rot decay on select wood properties of poplar (Populus cathayana Rehd.) and its mechanism of action

Holzforschung ◽  
2017 ◽  
Vol 71 (4) ◽  
pp. 355-362 ◽  
Author(s):  
Xiaowen Ge ◽  
Lihai Wang ◽  
Jiejian Hou ◽  
Binbin Rong ◽  
Xiaoquan Yue ◽  
...  
Keyword(s):  
Bending Strength ◽  
Chemical Properties ◽  
Brown Rot ◽  
Response Speed ◽  
Modulus Of Rupture ◽  
Crystalline Cellulose ◽  
Cellulose Content ◽  
Relative Crystallinity ◽  
Populus Cathayana ◽  
Brown Rot Decay

Abstract The effects of brown-rot decay on the mechanical and chemical properties of poplar (Populus cathayana Rehd.) wood were investigated, while the correlation of several properties to the decay degree and to each other were quantified. During the decay process, the losses in impact bending strength (IBS) and modulus of rupture (MOR) increased logarithmically with the degree of decay, whereas the losses in modulus of elasticity (MOE) and compressive strength parallel to grain (CS∥) increased slowly with linear trends. The ranking of the four mechanical parameters for the response speed to decay and the degree of the influence of decay were IBS>MOR>MOE>CS∥. Hemicelluloses were preferably decomposed by the brown-rot fungus. The prominent degradation of cellulose began from a weight loss (WL) of 18.7%, where the relative crystallinity decreased. In summary, the degradation of hemicelluloses caused a fast and significant decrease in IBS while the subsequent removal of paracrystalline cellulose resulted in MOR loss. The variation of MOE was in correlation with the cellulose content. A decrease in CS∥ was due to the slow deterioration of crystalline cellulose.

scholarly journals Durability of Accoya Wood in Ground Stake Testing after 10 Years of Exposure in Greece

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1638
Author(s):  
George I. Mantanis ◽  
Charalampos Lykidis ◽  
Antonios N. Papadopoulos
Keyword(s):  
Mechanical Properties ◽  
Weight Gain ◽  
Pinus Radiata ◽  
Modulus Of Elasticity ◽  
Brown Rot ◽  
Significant Loss ◽  
Modulus Of Rupture ◽  
Ground Contact ◽  
Central Greece ◽  
Brown Rot Decay

In this research, acetylated wood (Accoya) was tested in ground contact in central Greece. After ten years of exposure during a ground stake test, acetylated pine wood (Pinus radiata) stakes, with a 20% acetyl weight gain, were completely intact and showed no visual decay (decay rating: 0). However, the key mechanical properties of Accoya wood, that is, modulus of elasticity (MOE) and modulus of rupture (MOR) after 10 years of ground contact, were significantly reduced by 32.8% and 29.6%, respectively, despite an excellent visual result since no evidence of fungal attack was identified. This contradiction could possibly indicate that the hallmarks of decay, i.e., brown-rot decay of acetylated wood can be the significant loss of mechanical properties before decay is actually visible.

Production of Micro Crystalline Cellulose from Tapioca Solid Waste: Effect of Acid Concentration on its Physico-chemical Properties

2020 ◽  
Vol 23 (5) ◽  
pp. 147-151
Author(s):  
Ansharullah Ansharullah ◽  
Nur Muhammad Abdillah Saenuddin ◽  
RH Fitri Faradilla ◽  
Asranuddin Asranudin ◽  
Asniar Asniar ◽  
...  
Keyword(s):  
Solid Waste ◽  
Water Solubility ◽  
Chemical Properties ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Crystalline Cellulose ◽  
Cellulose Content ◽  
X Ray Diffraction ◽  
Physico Chemical ◽  
Ft Ir

This study was aimed to examine the production of microcrystalline cellulose (MCC) from tapioca solid waste (TSW), using HCl hydrolysis with various concentrations, i.e., 2 N, 2.5 N, 3 N, and 3.5 N. MCC was produced by delignifying the TSW with NaOH 20%, and bleaching with NaOCl 3.5% to produce α-cellulose, and subsequently hydrolyzing α-cellulose with three different HCl concentrations to produce MCC. The physicochemical properties of MCC were then analyzed, including Scanning Electron Micrograph (SEM), X-ray diffraction (XRD), and FTIR spectra. The results showed that hydrolysis with 2.0 N HCl resulted in a higher yield of 61.28%, α-cellulose content of 56.33%, moisture 6.25%, pH of 6.54; ash 0.23%, and water solubility 0.34%. SEM analysis showed the morphology and size of the MCC produced were like those of a commercial MCC (Avicel PH101), while the XRD analysis showed the higher concentration of HCl gave rise to an increased crystalline index. FT-IR spectrum analysis indicated that TSW, MCC produced, and commercial MCC had similar functional groups.

scholarly journals Development and characterization of hybrid coconut/glass fibers reinforced low density polyethylene composites for bumper application

10.30544/453 ◽  
2020 ◽  
Author(s):  
Akinlabi O. David ◽  
Ibeh Stanley Chukwuemeka ◽  
Enegide E. Osther ◽  
Garba N. Salihu
Keyword(s):  
Mechanical Properties ◽  
Glass Fiber ◽  
Bending Strength ◽  
Glass Fibers ◽  
Chemical Properties ◽  
Modulus Of Rupture ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Coconut Fiber ◽  
Polyethylene Matrix

The EU's End of Life Vehicles (ELV) regulations are forcing car manufacturers to consider the environmental impact of their production and possibly shift from the use of synthetic materials to the use of agro-based materials. However, poor mechanical properties and certain manufacturing limitations currently limit the use of agro-based materials to non-structural and semi-structural automotive components. This research is focused on a composite of hybrid coconut/glass fiber as reinforcement in recycled low density polyethylene matrix alone to enhance the desired mechanical properties for car bumper as automotive structural components. X-ray fluorescence analysis conducted on coconut fiber showed the presence of silica and alumina materials make coconut fibre a choice one. Morphology analysis was performed using scanning electron microscopy (SEM), which reveals that there are small discontinuities and reasonably uniform distribution of the reinforcement fibers and the reinforced low density polyethylene (RLDPE) binder resulting to better mechanical properties. Physic-chemical properties that directly affect developed composite such as variation of Density, Water Absorption, Tensile Strength, Bending strength, Modulus of rupture, Impact Strength and Hardness Values were investigated for both unhybridized and hybridized developed composite. The study shows the successful development of composites of coconut fiber (CF) hybridized with glass fiber (GF) and reinforced low density polyethylene (RLDPE) binder using a simple molding technique. Hybridized samples (CF-GF/RLDPE) showed higher strength when compared to un-hybridized (CF/RLDPE) composites. Better microstructural bonding exists with 25% and 30% wt CF-GF composite resulting in good mechanical properties for the hybridized composites. The grades of composites obtained in the course of this study are applicable in the production of low strength car bumpers.

Effect of different soils and pH amendments on brown-rot decay activity in a soil block test

Holzforschung ◽  
2010 ◽  
Vol 64 (5) ◽  
Author(s):  
Nathan S. Little ◽  
Tor P. Schultz ◽  
Darrel D. Nicholas
Keyword(s):  
Calcium Chloride ◽  
Chemical Properties ◽  
Brown Rot ◽  
Hydrated Lime ◽  
Laboratory Method ◽  
Water Soluble ◽  
Fungal Decay ◽  
Soil Block ◽  
Brown Rot Decay ◽  
Block Test

Abstract The soil block test is the most widely employed laboratory method for determination of biocide efficacy in North America. However, surprisingly little is known about the effect of different soil properties and soil amendments on fungal decay. Four soils with different textures and chemical properties were obtained and characterized. These soils, with and without pH amendments, were submitted to one soil block decay study using untreated southern pine wood and two brown-rot fungi. A second study examined the effect of adding water-soluble calcium chloride to soils, or directly to wood, on brown-rot decay. Based on the results of the first study with a limited number of soils, changes in the specified properties of the soil are suggested. Generally, fungal decay was reduced by raising the soil pH for acidic soils by hydrated lime as specified in the standards, or by adding water-soluble acidic calcium chloride to basic soils.

scholarly journals Involvement of CesA4, CesA7-A/B and CesA8-A/B in secondary wall formation in Populus trichocarpa wood

2019 ◽  
Vol 40 (1) ◽  
pp. 73-89 ◽  
Author(s):  
Manzar Abbas ◽  
Ilona Peszlen ◽  
Rui Shi ◽  
Hoon Kim ◽  
Rui Katahira ◽  
...  
Keyword(s):  
Solid State ◽  
Mechanical Strength ◽  
Cell Walls ◽  
Secondary Wall ◽  
Populus Trichocarpa ◽  
Wood Formation ◽  
Fiber Cell ◽  
Modulus Of Rupture ◽  
Cellulose Content ◽  
Wall Formation

Abstract Cellulose synthase A genes (CesAs) are responsible for cellulose biosynthesis in plant cell walls. In this study, functions of secondary wall cellulose synthases PtrCesA4, PtrCesA7-A/B and PtrCesA8-A/B were characterized during wood formation in Populus trichocarpa (Torr. & Gray). CesA RNAi knockdown transgenic plants exhibited stunted growth, narrow leaves, early necrosis, reduced stature, collapsed vessels, thinner fiber cell walls and extended fiber lumen diameters. In the RNAi knockdown transgenics, stems exhibited reduced mechanical strength, with reduced modulus of rupture (MOR) and modulus of elasticity (MOE). The reduced mechanical strength may be due to thinner fiber cell walls. Vessels in the xylem of the transgenics were collapsed, indicating that water transport in xylem may be affected and thus causing early necrosis in leaves. A dramatic decrease in cellulose content was observed in the RNAi knockdown transgenics. Compared with wildtype, the cellulose content was significantly decreased in the PtrCesA4, PtrCesA7 and PtrCesA8 RNAi knockdown transgenics. As a result, lignin and xylem contents were proportionally increased. The wood composition changes were confirmed by solid-state NMR, two-dimensional solution-state NMR and sum-frequency-generation vibration (SFG) analyses. Both solid-state nuclear magnetic resonance (NMR) and SFG analyses demonstrated that knockdown of PtrCesAs did not affect cellulose crystallinity index. Our results provided the evidence for the involvement of PtrCesA4, PtrCesA7-A/B and PtrCesA8-A/B in secondary cell wall formation in wood and demonstrated the pleiotropic effects of their perturbations on wood formation.

scholarly journals Assessment of Pellets from Three Forest Species: From Raw Material to End Use

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 447
Author(s):  
Miguel Alfonso Quiñones-Reveles ◽  
Víctor Manuel Ruiz-García ◽  
Sarai Ramos-Vargas ◽  
Benedicto Vargas-Larreta ◽  
Omar Masera-Cerutti ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Ash Content ◽  
Hot Water ◽  
Raw Material ◽  
Chemical Components ◽  
Energy Yield ◽  
Cellulose Content ◽  
Fixed Carbon ◽  
End Use ◽  
The Impact

This study aimed to evaluate and compare the relationship between chemical properties, energy efficiency, and emissions of wood and pellets from madroño Arbutus xalapensis Kunth, tázcate Juniperus deppeana Steud, and encino colorado Quercus sideroxyla Humb. & Bonpl. in two gasifiers (top-lit-up-draft (T-LUD) and electricity generation wood camp stove (EGWCS)) in order to determine the reduction of footprint carbon. In accordance with conventional methodologies, we determined the extracts and chemical components (lignin, cellulose, holocellulose), and the immediate analyses were carried out (volatile materials, fixed carbon, ash content and microanalysis of said ash), as well as the evaluation of emission factors (total suspended particulate matter (PM2.5), CO, CO2, CH4, black carbon (BC), elemental carbon (EC), and organic carbon (OC)). The results were statistically analyzed to compare each variable among species and gasifiers. The raw material analyzed showed how the pH ranged from 5.01 to 5.57, and the ash content ranged between 0.39 and 0.53%. The content values of Cu, Zn, Fe, Mg, and Ca ranged from 0.08 to 0.22, 0.18 to 0.19, 0.38 to 0.84, 1.75 to 1.90, and 3.62 to 3.74 mg kg−1, respectively. The extractive ranges from cyclohexane were 2.48–4.79%, acetone 2.42–4.08%, methanol 3.17–7.99%, and hot water 2.12–4.83%. The range of lignin was 18.08–28.60%. The cellulose content ranged from 43.30 to 53.90%, and holocellulose from 53.50 to 64.02%. The volatile material range was 81.2–87.42%, while fixed carbon was 11.30–17.48%; the higher heating value (HHV) of raw material and pellets presented the ranges 17.68–20.21 and 19.72–21.81 MJ kg−1, respectively. Thermal efficiency showed statistically significant differences (p < 0.05) between pellets and gasifiers, with an average of 31% Tier 3 in ISO (International Organization for Standardization) for the T-LUD and 14% (ISO Tier 1) for EGWCS, with Arbutus xalapensis being the species with the highest energy yield. The use of improved combustion devices, as well as that of selected raw material species, can reduce the impact of global warming by up to 33% on a cooking task compared to the three-stone burner.

scholarly journals Two β-glucuronosyltransferases involved in the biosynthesis of type II arabinogalactans function in mucilage polysaccharide matrix organization in Arabidopsis thaliana

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Oyeyemi O. Ajayi ◽  
Michael A. Held ◽  
Allan M. Showalter
Keyword(s):  
Arabidopsis Thaliana ◽  
Seed Size ◽  
Seed Coat ◽  
Glucuronic Acid ◽  
Industrial Applications ◽  
Crystalline Cellulose ◽  
Sugar Residue ◽  
Composition Analysis ◽  
Cellulose Content ◽  
Type Ii

Abstract Background Arabinogalactan-proteins (AGPs) are heavily glycosylated with type II arabinogalactan (AG) polysaccharides attached to hydroxyproline residues in their protein backbone. Type II AGs are necessary for plant growth and critically important for the establishment of normal cellular functions. Despite the importance of type II AGs in plant development, our understanding of the underlying role of these glycans/sugar residues in mucilage formation and seed coat epidermal cell development is poorly understood and far from complete. One such sugar residue is the glucuronic acid residues of AGPs that are transferred onto AGP glycans by the action of β-glucuronosyltransferase genes/enzymes. Results Here, we have characterized two β-glucuronosyltransferase genes, GLCAT14A and GLCAT14C, that are involved in the transfer of β-glucuronic acid (GlcA) to type II AGs. Using a reverse genetics approach, we observed that glcat14a-1 mutants displayed subtle alterations in mucilage pectin homogalacturonan (HG) compared to wild type (WT), while glcat14a-1glcat14c-1 mutants displayed much more severe mucilage phenotypes, including loss of adherent mucilage and significant alterations in cellulose ray formation and seed coat morphology. Monosaccharide composition analysis showed significant alterations in the sugar amounts of glcat14a-1glcat14c-1 mutants relative to WT in the adherent and non-adherent seed mucilage. Also, a reduction in total mucilage content was observed in glcat14a-1glcat14c-1 mutants relative to WT. In addition, glcat14a-1glcat14c-1 mutants showed defects in pectin formation, calcium content and the degree of pectin methyl-esterification (DM) as well as reductions in crystalline cellulose content and seed size. Conclusions These results raise important questions regarding cell wall polymer interactions and organization during mucilage formation. We propose that the enzymatic activities of GLCAT14A and GLCAT14C play partially redundant roles and are required for the organization of the mucilage matrix and seed size in Arabidopsis thaliana. This work brings us a step closer towards identifying potential gene targets for engineering plant cell walls for industrial applications.

scholarly journals The effect of microstructural features on the mechanical properties of LZSA glass-ceramic matrix composites

Cerâmica ◽  
2013 ◽  
Vol 59 (351) ◽  
pp. 351-359 ◽  
Author(s):  
F. M. Bertan ◽  
A. P. Novaes de Oliveira ◽  
O. R. K. Montedo ◽  
D. Hotza ◽  
C. R. Rambo
Keyword(s):  
Glass Ceramic ◽  
Bending Strength ◽  
Chemical Properties ◽  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Linear Shrinkage ◽  
Matrix Composites ◽  
Particulate Reinforced ◽  
And Chemical Properties

This work reports on the characterization of ZrSiO4 particulate-reinforced Li2O-ZrO2-SiO2-Al2O3 (LZSA) glass-ceramic matrix composites. The typical physical/mechanical and chemical properties of the glass batches and the composites were measured. A composition with 60 wt.% ZrSiO4 was preliminarily selected because it demonstrated the highest values of bending strength (190 MPa) and deep abrasion resistance (51 mm³). To this same composition was given a 7 wt.% bentonite addition in order to obtain plasticity behavior suitable for extrusion. The sintered samples (1150 ºC for 10 min) presented a thermal linear shrinkage of 14% and bending strength values of 220 MPa.

scholarly journals Particleboards from Recycled Thermally Modified Wood

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1462
Author(s):  
Ján Iždinský ◽  
Zuzana Vidholdová ◽  
Ladislav Reinprecht
Keyword(s):  
Mechanical Properties ◽  
Urea Formaldehyde ◽  
Brown Rot ◽  
Decay Resistance ◽  
Raw Material ◽  
Modulus Of Rupture ◽  
Negative Effect ◽  
Serpula Lacrymans ◽  
Thermally Modified Wood ◽  
Modified Wood

In recent years, the production and consumption of thermally modified wood (TMW) has been increasing. Offcuts and other waste generated during TMWs processing into products, as well as already disposed products based on TMWs can be an input recycled raw material for production of particleboards (PBs). In a laboratory, 16 mm thick 3-layer PBs bonded with urea-formaldehyde (UF) resin were produced at 5.8 MPa, 240 °C and 8 s pressing factor. In PBs, the particles from fresh spruce wood and mixed particles from offcuts of pine, beech, and ash TMWs were combined in weight ratios of 100:0, 80:20, 50:50 and 0:100. Thickness swelling (TS) and water absorption (WA) of PBs decreased with increased portion of TMW particles, i.e., TS after 24 h maximally about 72.3% and WA after 24 h maximally about 64%. However, mechanical properties of PBs worsened proportionally with a higher content of recycled TMW—apparently, the modulus of rupture (MOR) up to 55.5% and internal bond (IB) up to 46.2%, while negative effect of TMW particles on the modulus of elasticity (MOE) was milder. Decay resistance of PBs to the brown-rot fungus Serpula lacrymans (Schumacher ex Fries) S.F.Gray increased if they contained TMW particles, maximally about 45%, while the mould resistance of PBs containing TMW particles improved only in the first days of test. In summary, the recycled TMW particles can improve the decay and water resistance of PBs exposed to higher humidity environment. However, worsening of their mechanical properties could appear, as well.

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