Holocellulose Research Articles

Assessing the efficacy of date-pits holocellulose as a novel additive candidate for ruminant feeding.

Holocellulose (HC) fraction extracted from date-pits was evaluated as a novel feed additive for ruminant feeding. This study was performed to investigate the effectiveness of the HC additive on rumen fermentation, methane (CH4) production, and diet degradability over 24h of in vitro incubation. Three independent incubation trials were conducted over three consecutive weeks, employing the same in vitro methodology to assess four treatment doses in a completely randomized design. The experimental diet incorporated four increasing doses of HC, containing HC at 0 (HC0), 10 (HC10), 20 (HC20), and 30 (HC30) g/kg dry matter (DM). In vitro gas production (GP) and CH4 production, volatile fatty acids (VFAs) concentration, protozoa accounts, degraded organic matter (DOM), metabolizable and net energy (ME and NE), and hydrogen (H2) estimates were measured. No significant differences in ruminal pH were observed as the HC doses gradually increased. All incremental doses of HC additive over 24h resulted in a linear increase in GP (P < 0.001), DOM (P < 0.001), total VFAs (P = 0.011), and propionate (P < 0.001) concentrations, as well as estimated energy (ME and NE) (P < 0.05) and microbial protein (P = 0.017) values. However, the inclusion of increasing doses of HC in the diet displayed linear reductions in the net CH4 production (ml/kg DOM; P = 0.002), protozoa abundance (P = 0.027); acetate (P = 0.029), and butyrate (P < 0.001) concentrations, the acetate-to-propionate ratio (P < 0.001), and the estimated net H2 production concentration (P = 0.049). Thus, the use of date-pits HC additive generated positive ruminal fermentability, including increased total VFAs and a reduction in the acetate-to-propionate ratio, leading to decreased CH4 output over 24h of in vitro incubation. Hence, HC could be considered a potent feed additive (at up to 30g/kg DM), demonstrating promising CH4-mitigating competency and thereby enhancing energy-use efficiency in ruminants.

Salt-resistance holocellulose-based solar steam evaporator for desalination brine water

Interfacial solar-powered water evaporation is a cost-effective and sustainable approach using solar energy for seawater desalination. Nevertheless, salt accumulation during solar desalination generally restricts the widespread application of solar vapor generation. Herein, taking merits of the excellent hydrophilicity and inherent porosity of holocellulose (HC), An excellent salt-resistant solar steam evaporator for long-term interfacial solar water desalination was fabricated by decorating polypyrrole (PPy) on the surface of HC. Due to the broadband light absorbance of PPy and the superhydrophilic HC substrate, the PPy-HC evaporator exhibited a high evaporation rate of 1.45 kg m−2 h−1 and conversion efficiency of 93.4 % in a 5 wt% NaCl solution under one sun illumination. Importantly, the evaporator presented superior salt-resistance and stability during long-term cycling test in high salinity brine. This work reveals the key role of superhydrophilicity and water transportation capability in high salt solution solar-driven desalination. Thus, this work provides an effective approach to address the issue of salt accumulation of the traditional evaporator, demonstrating its great potential for real-world solar-driven seawater desalination.

Methyl levulinate synthesis from rice husk employing e-waste derived silica supported nano CuO–CdSO4 photocatalyst: Assessment of production environmental impacts, engine performance and emissions

Applications of E-waste recovered silica (support) and copper citrate (precursor) for the synthesis of nano CuO–CdSO4 doped photocatalyst (NCCP) for subsequent employment in sustainable conversion of rice husk (RH) to drop-in biofuels viz. methyl levulinate (ML) have been explored. The prepared NCCP (low Eg = 2.0 eV) was employed for alcoholytic depolymerization (AD) to produce ML from holocellulose (HOC) extracted from RH through infrared assisted delignification. Taguchi orthogonal design predicted the optimal values of the AD viz. HOC: Water (1:5 w/w), NCCP concentration (1 wt%), HOC: methanol (1:30 w/w) and AD time (125 min) rendering 96.97% ML yield deploying combined ultrasonication-UV energies at 60 °C; saving 30% energy compared to conventional heating system. Noticeably, this is the first insightful investigation on the application of ML as a diesel additive demonstrating significant diminutions (25.92% and 83.33% for CO and HC) in harmful emissions. The LCA of the overall ML synthesis indicates remarkable reduction in environmental pollution with 63.63% and 66.66% mitigations in GWP and ecotoxicity respectively. Thus, a sustainable ML synthesis protocol encompassing the development of E-waste derived nanophotocatalyst through conversion of rice husk and its successful use as a diesel additive could be established.

Sugarcane Bagasse Fibers Derivatives and Their Application in Chitosan-Based Composite Films for NPK Fertilizer Release

Encapsulation and release of NPK fertilizer by composite films were systematically demonstrated by casting dispersions of chitosan (CS) and sugarcane bagasse (SCB) derivatives (holocellulose (HC), cellulignin (CL), and cellulose (CEL)) fibers under varied CS-to-NPK and CS-to-SCB derivatives mass ratios. SCB derivatives were obtained from sugarcane bagasse as agricultural waste by following the alkali dissolution (4% NaOH, 70 °C for 5 min), sodium chlorite delignification (1.4% NaClO2, pH 3.5, 70 °C, 5 h), or from a combination of both. Nutrientadsorption capacity can be tunable by the chemical composition of SCB derivatives, i.e., fibers with noncellulosics exhibited higher adsorption capacities while the absence of noncellulosics lessened their adsorption capacity. Oven-drying (60 °C, 5 h) of optimal 1:0.5 CS/NPK film‑forming solution produced highly uniform films with shape with 0.31 ± 0.02 mm thickness while increasing fiber content in the solution to 25 or 50% prevents films retraction effect. The release of highly watersoluble NPK fertilizer from these composite films was lower with hemicelluloses (52-82%) or lignin (55-92%) contents in SCB fiber than in noncellulosics absence (71-100%), thus could be tuned by varying the chemical composition SCB derivative, followed by a quasi-Fickian diffusion mechanism in water.

Elucidating the inhibiting mechanism of pseudo-lignin on the enzymatic digestibility of cellulose by surface plasmon resonance

To explore the interaction mechanism of pseudo-lignin (PL) with cellulase and its influence on cellulose hydrolysis, different PLs were extracted from pretreated bamboo holocellulose (HC) using different organic solvents. Meanwhile, the real-time interaction of PL and cellulase was analyzed using surface plasmon resonance (SPR). The results showed that the extraction effect of the tetrahydrofuran and 1, 4-dioxane/water solution on PL was more effective than the ethanol/water solution. The inhibition of PL fraction obtained from HC by acid pretreatment with higher temperature showed less effect on Avicel’s enzymatic hydrolysis. SPR analysis revealed that PL formed at higher pretreatment temperature had a lower dissociation rate after adsorption with cellulase. Besides, the binding affinity of PL (160 °C) to cellulase was much greater than that of PL obtained from 180 °C, indicating PL extracted at higher temperature treated biomass is more easily dissociated from cellulase after binding.

Effect of Initial Planting Density on the Moisture Content and Chemical Composition of the Triploid Chinese White Poplar (Populus× tomentosa Carrière) Plantation

The triploid Chinese white poplar (Populus × tomentosa Carrière) features desirable growth traits and wood properties, making it the preferred species in the pulp and paper industries and the sawn timber industry. In this study, we characterized the effects of initial planting densities on the moisture content (MC) and four chemical components (benzene-alcohol (BA), holocellulose (HC), alpha-cellulose (AC), and klason lignin (KL)) of the triploid Chinese white poplar. In this study, 11-year-old Chinese white poplars with three triploid clones (S86, B331, and B301) and one diploid clone (1316) that were planted using seven levels of planting densities (2490, 1665, 1110, 832, 624, 499 and 416 trees/hm2) were examined in the Huabei Great Plain in China. The MC was observed to initially decrease and then subsequently increase with decreasing planting density, and exhibited significant differences under different initial planting densities (0.001 &lt; p &lt; 0.01). In terms of the chemical composition, the BA content of the triploid hybrid clones presented with much higher phenotypic variation (CVp = 17.11%–32.45%) at each planting density compared to either the MC (CVp = 3.73%–11.21%) or the other three chemical composition variations (CVp = 1.16%–11.46%). Substantial differences were observed in the chemical composition of the triploid hybrid clones (p &lt; 0.05), while no differences were found in the chemical composition within the initial planting density categories. The correlation between the chemical composition of wood (BA, HC, AC, and KL) and growth traits was generally weak. These results demonstrate that compared with the MC, the chemical composition of the triploid Chinese white poplar was primarily controlled by its own genetic background and was almost unaffected by the initial planting density. Thus, it is important to select a suitable clone and initial planting density to ensure the full growth of these trees and to improve the quality of pulping in the construction of pulp timber forests.

Preparation of regenerated cellulose from rice straw lignocellulosic waste and its use for reinforced paper products

Rice straw waste is a lignocellulosic waste produced by farmers in large quantities. In this study, regenerated cellulose (RC) from rice straw was prepared by dissolving rice straw holocellulose (HC) in NaOH/Urea/Thiourea/Water solution by the freeze-thawing process. The crystallinity index of RC was calculated at 31%, which is out of the crystallinity range of 39%–69% that has been previously suggested. The study indicated that the RC is amorphous with a low degree of polymerization (638) and higher hydroxyl group content as compared to HC. The fiber length of RC was found to be 26.7% shorter; however, the width of RC was 21.2% higher as compared to HC. Reduced kinked fiber content was observed in the fraction of RC (18.3%) as compared with HC (39.1%), and a higher curl index of fiber was observed more so in HC (10.5%) than RC (5.6%). Because of the regeneration process, the fiber length was reduced and a fines element content of about 96% was observed in RC compared to the initial fines content of HC (56.9%). Irrespective of the high fines element content of RC, the composite paper of rice straw bleached pulp and RC fibers was developed with an increase in the tensile index from 41.4 N.m/g to 71.2 N.m/g and an increase in the burst index from 4.7 kPa.m2/g to 5.3 kPa.m2/g with the addition of 5% and 15% RC, respectively. However, enhanced tear index of paper was observed up to 5% and then it declined upon further addition of RC. The study revealed that regenerated cellulose can be used as a strength additive to overcome the shortcomings of low mechanical properties in paper products.

Insights into the effect of hydrolysis medium on the holocellulose decomposition, furfural, and pseudo‐lignin formation

AbstractIn this work, four different media including aqueous water, acetic acid (AA), HCl, and H2SO4 were used to hydrolyze holocelluloses. The decomposition of holocellulose and pseudo‐lignin formation are discussed. It was found that AA and water are almost comparable in catalyzing holocellulose (HC) decomposition but the former can promote sugar decomposition and therefore pseudo‐lignin formation. In contrast, HCl and H2SO4 are more efficient in HC decomposition and furfural formation; specifically, HCl is extremely potent for HC decomposition and furfural formation but inert for pseudo‐lignin formation. The results confirmed that both hydrogen ions and anions would affect the carbohydrate decomposition; in this case, further study revealed that only concentrated Cl− in the water system can promote the furfural formation but Cl− with relative low concentration will inhibit pseudo‐lignin formation. It is proved that, Cl− can stabilize the intermediates that facilitate the pseudo lignin formation. © 2021 Society of Industrial Chemistry and John Wiley &amp; Sons Ltd.

Impact of natural disturbance, forest management and vegetation cover on topsoil biochemical characteristics of Tatra Mts. (Slovakia)

Perturbations caused by windstorms usually lead to the harvesting and clearcutting of fallen trees and wood debris, especially in the areas of managed forest ecosystems. Induced shifts in soils due to management practices play a crucial role in the restoration and maintaining of key ecosystem services. This paper focuses on topsoil chemical properties in relation to vegetation type (trees, shrubs and herbs) evolving at windstorm damaged (in 2004) areas with former Norway spruce (Picea abies) forests in the Tatra Mts. region (Slovakia). We assessed the content of topsoil organic matter fractions (extractives, holocellulose (HC) and lignin (Lig)), carbon in microbial biomass (Cmic), soil organic matter (SOM) and the content of elements N, C, H and S. The study plots represent different types of post-windthrow disturbance history/regime: wooden debris extraction (EXT), wooden debris not extracted (NEX), wooden debris extraction followed by wildfire (FIR), affected by the windstorm in 2014 with the subsequent wooden debris extraction (REX) and unaffected (REF). Our results revealed significant differences among sites in the content of dichloromethane extractives (EXT vs. REX and FIR), acetone extractives (NEX vs. EXT, FIR and REF), ethanol extractives (FIR vs. EXT, NEX and REF), water extractives (FIR vs. REX, NEX) and Cmic (EXT vs. NEX, FIR and REF). The topsoil of Vaccinium myrtillus and Picea abies showed a higher ratio of C/N, N/Lig, and Lig/HC compared to Rubus idaeus, Avenella flexuosa, Calamagrostis villosa, and Larix decidua. The content of N, C, H and S varied between topsoil with shrubs (Vaccinium myrtillus, Rubus idaeus) and grasses (Avenella flexuosa, Calamagrostis villosa). A positive correlation between soil organic matter (SOM) and polar extractives (r=0.81) and a negative correlation between SOM and HC (r=−0.83) was revealed. The carbon content in microbial biomass (Cmic) is positively correlated with acid soluble lignin (ASL) (r=0.85). We also identified a strong correlation between Klason lignin (KL) and the Lig/HC ratio (r=0.97).

Selecting for water use efficiency, wood chemical traits and biomass with genomic selection in a Eucalyptus breeding program

The selection of ideotypes combining high biomass production, high water use efficiency (WUE) and adequate wood properties is a major challenge in improving forest trees for industrial plantations. This issue was addressed in a field experiment evaluating 1130 clones of Eucalyptus urophylla * Eucalyptus grandis. Genomic selection using 3303 SNPs and the GBLUP model was carried out at age 55 months to select genitors and clones for stem volume (V55), WUE (using stable carbon isotope composition in stemwood, δ13C as a proxy, transformed into intrinsic WUE, Wi), as well as lignin (KL) and holocellulose (HCEL) contents. The variance components were mainly additive for δ13C(Wi), KL and HCEL, while they were highly non-additive for V55 (the ratio of dominance to additive variance was 130%). The narrow sense heritability was higher for Wi (h2 = 0.704) than for volume and wood traits (<0.5), showing that this trait was under strong genetic control. Additive and total genetic correlations among traits were low (between −0.260 and 0.260) as were the correlations due to environmental effects (between −0.267 and 0.344), which suggests a rather independence among traits. The equal emphasis and the desired gain index selection methods were used to assess economic weights and to estimate the expected additive and total genetic gains. Different breeding objectives were defined with percentages weighting the economic coefficients or the desired gain for the equal emphasis or desired gain method, respectively. When the breeding objective gave emphasis to volume production using the percentages of 70%, 10%, 10%, and 10% for V55, HCEL, KL and Wi, respectively, positive gains were observed in both methods, but the correlation between index rankings were 0.686 and 0.635 for breeding and clonal selection, respectively. With a more balanced breeding objective using percentages such as 25%, 25%, 25%, 25% for V55, HCEL, KL and Wi, respectively, both index methods gave close positive gains and similar rankings, the correlation between index rankings ranging from 0.941 to 0.982 for parent selection and from 0.883 to 0.903 for clone selection. With more contrasted percentages between V55 and Wi, such as (80%, 10%, 10%, 0%) or (90%, 10%, 10%, −10%), the gain increased for V55 and was close to the maximum and decreased markedly for Wi. This study explores the magnitude of economic coefficients for index selection and shows that positive genetic gains can be achieved by associating biomass, a proxy of WUE and wood chemical traits. It provides encouraging results for selecting Eucalyptus varieties adapted to dry zones while maintaining good performances regarding other economic traits.

Determination of Organic Fractions and Enzymatic Activity in Forest Spruce Soil of Tatra National Park

Abstract The formation and quality of soil organic matter (SOM) highly depends on the input of organic material and microbial enzymatic activities. Soil extractions with specific nonpolar and polar extractives can be used to identify qualitative changes in SOM. The aim of this paper was to understand the correlations among microbial enzymatic activity and specific organic fractions in acidic spruce forest soil. Klason lignin (KL), acid soluble lignin (ASL), holocellulose (HC), SOM content, and potential enzymatic activity (FDA and phosphatase) was measured and analyzed. We sampled Dystric Cambisol of forest spruce stands (Picea abies) in Tatra National Park (Slovakia). The SOM fractions were determined gravimetrically based on their extractivity in nonpolar (dichloromethane (DME)) and polar (acetone (AE), ethanol (EE), water (WE)) solvents Total extractives content was 0.079% and nonpolar extractives 0.036%. The mean amount of polar extractives tented to increase in the order EE&lt;AE&lt;WE. The total lignin content was determined to be 1.079% and HC 0.774%. FDA negatively correlated with KL (r=-0.873 p&lt;0.05) and DME (r=-0.913 p&lt;0.05). Phosphatase positively correlated with WE (r=0.972 p&lt;0.01) and KL (r=0.957 p&lt;0.01).

Effect of Temperature on the Physical, Electro-Chemical and Adsorption Properties of Carbon Micro-Spheres Using Hydrothermal Carbonization Process.

This research deals with the effect of the temperature on the physical, thermal, electrochemical, and adsorption properties of the carbon micro-spheres using hydrothermal carbonization (HTC). Until recently, limited research has been conducted regarding the effects of delignification during the HTC process of biomass residues especially Dimocarpus longan. In this regard, lignin was first extracted from the lingo-cellulosic waste of Longan fruit peel (Dimocarpus longan). The holocellulose (HC) separated from lignin and raw biomass substrates (Longan fruit exocarp/peel powder, LFP) were carbonized at different temperatures using water as the green catalyst. Hydrothermal carbonization (HTC) was performed for both of the samples (LFP and HC) at 200 °C, 250 °C, and 300 °C for 24 h each. The surface morphological structures, the porosity, and the Brunauer-Emmett-Teller (BET) surface area of the prepared micro-spherical carbon were determined. The BET surface areas obtained for HC-based carbon samples were lower than that of the raw LFP based carbon samples. The carbon obtained was characterized using ultimate and proximate analyses. The surface morphological features and phase transformation of the synthesized micro-spherical carbon was characterized by a field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) analysis. The results demonstrated that the extraction of lignin could significantly alter the end properties of the synthesized carbon sample. The carbon spheres derived from LFP showed a higher carbon content than the HC-based carbon. The absence of lignin in the holo-cellulose (HC) made it easy to disintegrate in comparison to the raw, LFP-based carbon samples during the HTC process. The carbonaceous samples (LFP-300 and HC-300) prepared at 300 °C were selected and their adsorption performance for Pb (II) cations was observed using Langmuir, Freundlich, and Temkin linear isotherm models. At 30 °C, the equilibrium data followed the Langmuir isotherm model more than the Freundlich and Temkin model for both the LFP-300 sample and the HC-300 sample. The potential of the synthesized carbon microspheres were further analyzed by thermodynamic characterizations of the adsorption equilibrium system.

Temporal decomposition sampling and chemical characterization of eucalyptus harvest residues using NIR spectroscopy and chemometric methods

Near-infrared (NIR) spectroscopy and chemometric methods were used to predict the chemical properties of decomposing eucalyptus harvest residues to better understand the decomposition process of these materials. Leaves, twigs, branches, and bark from a decomposition experimental set up in commercial plantations were sampled for one year. The contents of carbon (C), nitrogen (N), extractives (EX), acid-soluble lignin (SL), Klason insoluble lignin (KL) and holocellulose (HC) were determined by the reference method in the collected samples. Principal component analysis (PCA) was employed to distinguish the types of harvest residues throughout the decomposition period. Multi-residue regression models were built from the NIR spectra using partial least squares regression (PLS). Two feature selection methods, i.e., ordered predictors selection (OPS) and genetic algorithm (GA), were applied and compared. The OPS and GA did not differ statistically; however, compared with the GA, OPS was more computationally efficient and selected fewer variables. Using the PLS-OPS models, the root mean square errors of prediction (RMSEP) for C, N, EX, SL, KL and HC were 19.70, 0.08, 0.74, 0.39, 28.13 and 33.99, respectively, and the prediction correlations (Rp) for these properties were 0.94, 0.99, 0.99, 0.99, 0.96 and 0.98, respectively. PLS-discriminant analysis (PLS-DA) was used to classify the samples over the decomposition time and provided a good separation. Some mismatches obtained in the modeled classes were explained by the differences in the decomposition rate and changes in the chemical composition of the different harvest residue components that were evaluated. The results showed the feasibility of NIR spectroscopy and chemometric methods to evaluate the chemistry of decomposing eucalyptus harvest residues, indicating that these methods can be used as rapid and inexpensive alternatives to conventional methods to help understand the decomposition process.

Lignin and holocellulose from pecan nutshell as reinforcing fillers in poly (lactic acid) biocomposites

Lignocellulose from agro-food biowaste represents a valuable source of cost-effective structural fillers for wholly renewable polymer composites. In this work, pecan (Carya illinoinensis) nutshell (NS) fiber and its structural components, holocellulose (HC) and acid insoluble lignin (AIL), were isolated, characterized and used as reinforcing fillers to manufacture poly(lactic acid) (PLA) based biocomposites. Thermal, morphological and mechanical properties of the prepared materials were analyzed. NS and HC acted as heterogeneous nucleating agents, potentially able to control PLA physical aging. Moreover, they significantly enhanced the viscoelastic response of PLA, mainly restricting the melt molecular mobility due to hydrodynamic effects and the formation of a three-dimensional particulate network. Flexural tests demonstrated that HC induced a 25% increase in modulus compared to the plain polymer. AIL, conversely, conferred higher ductility to the PLA matrix producing an increase in stress and strain at break of 55% and 65%, respectively. Finally, all the biocomposites showed lower resilience with respect to plain PLA due to the lack of chemical adhesion between filler and matrix. These results emphasize the potential of NS as a source of reinforcing filler in polymer-based biocomposites.

Comparative study of cellulose/Ag nanocomposites using four cellulose types

The purpose of this study was to explore the influences of cellulose types on the cellulose/Ag nanocomposites via a microwave-assisted hydrothermal method. The cellulose/Ag nanocomposites were successfully fabricated using AgNO3 and four types of cellulose (cellulose nanocrystals (CNC), microcrystalline cellulose (MCC), cellulose fibers (CF), and holocellulose (HC)), in which the cellulose simultaneously served as the reducing agent and substrate for silver ions. The effects of different cellulose types on the products were investigated by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and thermogravimetric analysis (TGA). The experimental results revealed that the cellulose types played a vital role on the size, number, and morphology of silver nanoparticles (AgNPs). It is believed that these results could be a guidance for the synthesis of cellulose/Ag nanocomposites in the future.

Acid-insoluble lignin and holocellulose from a lignocellulosic biowaste: Bio-fillers in poly(3-hydroxybutyrate)

This paper deals with the valorization of a lignocellulosic biomass (LC), biowaste from the second generation bioethanol production process. LC was processed in order to isolate its main components: holocellulose (HC) and acid-insoluble lignin (IL). To obtain a biomass free of organic extractives (TE) and low molecular weight polar compounds (W), LC was also subjected to solvent extraction with toluene/ethanol and water. IL, HC and LC were characterized by SEM, FTIR and 13C MAS-NMR. The morphological and structural analysis evidenced successful separation of the two main fractions of the lignocellulosic biomass.LC and its derivatives were used as fillers in poly(3-hydroxybutyrate) (PHB). The blends were characterized through rotational rheometry and DSC. Moreover, the samples were also thermally treated at 190°C, and the effects of the thermal processing on the matrix molecular weight was evaluated by GPC.The addition of IL to PHB affected its rheological properties, significantly enhancing melt stability due to the formation of a percolated filler network within the matrix. Furthermore, SEM analysis demonstrated homogeneous dispersion of the filler and good interfacial adhesion with the matrix. LC and TE acted as pro-degrading agents toward PHB matrix causing a decrease in molecular weight of the polymer during the thermal treatment. The DSC analysis showed that LC, HC, W and TE promoted the polymer melt crystallization, potentially enabling to control physical aging of PHB.To sum up, this study provides an insight on the effect of a lignocellulosic biowaste and its derivatives on the properties of a naturally occurring, biodegradable polyester.

Dynamic vapour sorption of wood and holocellulose modified with thermosetting resins

Micro-veneers of wood and holocellulose (HC) were modified with the thermosetting resins phenol formaldehyde and melamine formaldehyde. The dynamic water vapour sorption of the modified and untreat ...

Biochemical Fractionation of Soil Organic Matter after Incorporation of Organic Residues

Soil organic matter (SOM) is a key factor for building and maintaining soil quality. The SOM quality is commonly assessed using densitometric and sieving separation methods, but such methods do not inform on the biochemical composition of SOM. Our objective was to evaluate the van Soest extraction procedure for soluble (SOL), holocellulose (HOLO) and lignin/cutin (LIC) fractions of SOM after incorporating crop residues and animal wastes into a C-depleted loamy sand. Millet cuttings, oat straw, fresh cattle manure and cattle manure compost were dried, sieved to obtain 53 - 250 and 250 - 2000 μm size fractions and characterized biochemically using a modified NDF-ADF-ADL van Soest method. Soil was also sieved into 53 - 250 and 250 - 2000 μm fractions. On a dry mass basis, crop residues contained 60% - 70% holocellulose while animal wastes contained more than 40% ash. Each soil fraction was combined with three rates of the corresponding organic fraction (2, 4, and 6 Mg&#183ha&#451 millet forage cuttings or oat straw and 5, 10, and 15 Mg&#183ha&#451 of cattle manure or cattle manure compost). Changes in soil biochemical components were analyzed using the balance method of compositional data analysis. Amendment, application rate and size fraction influenced significantly (p < 0.05) the [SOL | HOLO] balance but did not significantly affect the [SOL,HOLO | LIC] balance. The [SOL | HOLO] increased linearly with addition rate of crop residues, and decreased linearly with addition rate of animal wastes. This approach of balancing biochemical SOM components is a promising method to monitor the changes in SOM quality after the incorporation of organic residues and to elaborate beneficial practices for managing crop residues and animal wastes in agro-ecosystems.

Material pocket dynamic mechanical analysis: a novel tool to study thermal transition in wood fibers plasticized by an ionic liquid (IL)

Abstract The investigation of phase transition in powdered materials by dynamic mechanical analysis (DMA) is not straightforward because powders are difficult to prepare in a solid compact form without altering their structure and properties. In this study, a material pocket (MP) method has been applied to provide physical support to powdered samples for DMA testing (MP-DMA). Poplar wood strips and four types of wood particles [native wood flour (WF), α-cellulose (αC), holocellulose (HC), and particles without hemicelluloses (HR)] were treated with an ionic liquid (IL), 1-ethyl-3-methylimidazolium chloride ([Emim]Cl), to a weight percent gain (WPG) of 36%. Results show that all four [Emim]Cl-treated wood particles exhibited three apparent transition peaks over the measured temperature range. Paracrystalline cellulose, hemicelluloses, and lignin all exhibited a glass transition temperature (T g) at approximately 85°C due to the plasticizing effect of [Emim]Cl. The transition peak at a higher temperature may be due to the melting of crystalline cellulose in [Emim]Cl. MP-DMA is an effective tool for direct monitoring the phase transition of powdered lignocellulosics. This provides new insight into the interactions of ILs and cell wall polymers, and the method established can be easily extended to other systems based on powdered samples.

Morphology, mechanical properties, and dimensional stability of wood particle/high density polyethylene composites: Effect of removal of wood cell wall composition

Variation in the chemical composition of wood cell walls has a significant influence on the properties of wood plastic composites (WPCs). This study investigated the effect of removal of hemicellulose and/or lignin on the mechanical properties and dimensional stability of WPCs. Four types of wood particles with various compositions including native wood flour (WF), hemicellulose-removed particle (HR), holocellulose (HC), and α-cellulose (αC) were prepared and compounded with high density polyethylene (HDPE) in an extruder, both with and without maleated polyethylene. Injection molding was used to make test specimens. The HR-based composites exhibited the best water resistance. The HC-based composites obtained a greater tensile modulus but a lower water resistance. The highest values for tensile strength, elongation at brake, toughness, and impact strength were achieved by the composites filled with αC.