Cellulose最新文献

The simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA) is crucial for biomedical and clinical diagnostics. Herein, we present a highly sensitive and selective electrochemical sensor based on a modified glassy carbon electrode (GCE) functionalized with hydroxypropyl methylcellulose (HPMC), polyvinylpyrrolidone (PVP), and 3D reduced graphene oxide/pentaerythritol (3D rGO/PE). The structural and morphological properties of the composite were characterized using Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Electrochemical analysis demonstrated the remarkable electrocatalytic activity of 3D rGO/PE/PVP@HPMC/GCE for the oxidation of AA, DA, and UA, with peak potential separations of 214, 133, and 346 mV for DA-AA, DA-UA, and UA-AA, respectively. Under optimized conditions, the sensor exhibited wide linear detection ranges of 4.0 µM to 1.0 mM (AA), 0.2–100 µM (DA), and 1.0–100 µM (UA), with detection limits of 0.82, 0.002, and 0.025 M, respectively. The sensor demonstrated excellent sensitivity, selectivity, reproducibility, and stability, making it a promising platform for real-sample analysis.

This study applies supervised learning to predict the mechanical properties of biodegradable PLA/wood composites produced by Fused Filament Fabrication (FFF). PLA reinforced with 20 wt% wood fibers was printed under varying process conditions layer height, infill density, infill pattern, and raster orientation following a full factorial design of 81 experiments. Compressive strength, hardness, and tensile strength were experimentally evaluated to assess the influence of these parameters. Statistical analysis using ANOVA and the Taguchi method identified the most significant factors and their optimal combinations for improved performance. A Levenberg–Marquardt (LM)-based supervised learning model was developed to capture the nonlinear relationships between printing parameters and mechanical responses. The LM model showed strong predictive capability and consistent convergence, demonstrating its reliability for modelling the complex behavior of FFF-processed composites. Integrating statistical methods with data-driven modelling enables efficient optimization of process parameters and reduces experimental effort. The proposed approach provides a robust framework for enhancing the mechanical performance of sustainable PLA/wood composites and can be extended to other additive manufacturing systems for the design of high-performance, biodegradable materials.

With industrialization progressing rapidly, the discharge of printing and dyeing wastewater has risen significantly. This wastewater contains organic dyes like methylene blue (MB), posing a significant risk to the environment and human health. This study reports the successful fabrication of a multifunctional magnetic aerogel (ZACPF) with synergistic adsorption and catalytic properties. The aerogel was prepared by incorporating ZnO/Ag₂O heterojunctions into a dual-network hydrogel formed by cross-linking cellulose nanofibers (CNFs) and polyvinyl alcohol (PVA), followed by in-situ loading of magnetic Fe₃O₄. Experimental results showed that the aerogel has excellent adsorption performance for both cationic (416.34–984.52 mg/g) and anionic dyes (993.83–1025.95 mg/g) at 25 °C with pH 6.5. Characterization analyses confirm that the adsorption mechanism involves multi-site interactions, including electrostatic attraction, hydrogen bonding, and pore filling. When combined with H₂O₂, its degradation efficiency for MB at 20 mg/L was significantly enhanced, reaching 85.15% within 120 min at 25 °C with pH 6.5. The band alignment mechanism also facilitated the effective separation of photogenerated carriers, enabling a MB degradation rate of 98.91% under visible light within 60 min. Furthermore, the aerogel exhibited excellent recyclability, maintaining over 79.2% of its initial degradation efficiency after five cycles. In conclusion, this study presents an innovative strategy for developing high-performance aerogel catalysts to treat dye-contaminated water.

Quaternization of cotton enables its dyeing with anionic dyes and thus makes it possible to dye wool/cotton blends fabrics in one bath. However, research on the impact of the structures of EQASs on the dyeing properties of modified cotton fibers remain limited. In this study, three EQASs with varying alkyl chain lengths—EMAC-4, EMAC-8, and EMAC-10—were synthesized and used to modify cotton fibers. The dyeing properties of the modified cotton fibers were then investigated. As the alkyl chain length increased, the K/S values and fixation (F%) of the dyes on modified cotton fibers increased, while the leveling properties were somewhat compromised. When the modifier dosage was the same, EMAC-10 showed the best performance: at 20 g/L, EMAC-10 modified cotton fibers achieved 100% exhaustion (E%) and more than 93.4% fixation. Computational simulations revealed that as the alkyl chain length increased, the mobility of reactive dyes decreased, the reactivity of the newly introduced hydroxy groups increased, and the reaction energy barrier with monochloro-s-triazine reactive dyes was reduced. This study enhanced the understanding of the structure-performance relationship of cationic modifiers and provided a feasible direction for the design of efficient and environmentally friendly modifiers for cotton fibers.

Rice straw can be a valuable fiber raw material as a substitute of wood for the pulp and paper industry. However, rice straw is underutilized due to technical challenges in the pulping processes. In this study, a novel bio-chemi-mechanical pulping combines high-temperature aerobic fermentation pretreatment with alkaline hydrogen peroxide impregnation and two-stage mechanical refining. Firstly, aerobic fermentation destroyed the fiber structure of rice straw, loosened the connecting bond between carbohydrates and lignin and made the surface of rice straw rough and porous through microbial decomposition of lignocellulose. Subsequently, the molecular structure of rice straw was further altered by the synergistic action of NaOH and H₂O₂, and the efficiency of mechanical refining was further improved based on aerobic fermentation pretreatment at high-temperature (max. ~ 65–70 °C). Experimental results show that under the optimal process conditions, the fermentation pre-treatment resulted in about 65% energy saving, 27% water retention value improvement, and 112% increase in tensile strength at a given pulp freeness. The objective of this study is to transform rice straw lignocellulosic biomass into high-quality pulp with improved physical properties, while simultaneously lowering energy consumption.

Global environmental problems are becoming more and more serious, such as water pollution, soil pollution, air pollution and solid waste disposal are prominent, which damage the ecosystem as well as threaten the health and survival of human beings. Therefore, the search for sustainable and environmentally friendly materials has become a research focus in the fields of materials science and environmental science. Bacterial cellulose, as a natural polymer, is a type of sustainable material synthesized by microorganisms, which has unique advantages in structure and performance, such as high purity, high crystallinity, excellent mechanical properties, strong water-holding capacity, and good biocompatibility, degradability. These characteristics make bacterial cellulose show great application potential in the field of environmental remediation. The purpose of this article is to discuss the application of bacterial cellulose in different environmental problems, and analyze its potential and future research direction.

Wood is attracting attention as an environmentally friendly resource that does not burden the environment and is indispensable for the realization of a low-carbon society. In the field of construction, the use of heat-treated wood has been gaining traction in recent years for the purpose of improving dimensional stability and decay resistance. However, there have been few studies on the non-destructive measurement of the strength of heat-treated wood. Only cellulose, which accounts for about half of the major chemical components of wood, has a crystalline form, and changes in the interior of wood due to thermal treatment are thought to result from changes in this crystalline structure. Terahertz time-domain spectroscopy (THz-TDS) is suitable for crystallographic studies as the radiation energy in the THz region (0.1–10 THz; wave number 3.3–333 cm⁻¹) corresponds to lattice vibrations (phonons) of cellulose crystals. In this study, THz-TDS was used to evaluate the crystallinity of heat-treated cellulose and heat-treated wood powder. Wood pellets were measured by THz-TDS and X-ray diffraction (XRD) before and after the thermal treatment. The absorption peaks and XRD patterns were compared, and the effects of varying the temperature and duration of thermal treatment were investigated. Results indicated that crystallinity decreased rapidly at 250 °C, while at 200 °C, the reduction was more gradual, with signs of recrystallization. These findings suggest that factors such as temperature, humidity, and removal of non-crystalline components (e.g., hemicellulose, amorphous cellulose) are key in determining crystallinity during thermal treatment of wood.

Tampons are widely used hygiene products, yet there remains a lack of engineering-focused research on their design and functionality. A critical factor in tampon performance is the pore structure of the material, which directly influences liquid absorption. While micro-computed tomography has provided valuable insights into overall pore volume, it falls short in accurately characterizing individual pore sizes. In this study, we employ the sub-network of an over-segmented watershed (SNOW) algorithm alongside PoreSpy to obtain a detailed pore size distribution within tampon proxy materials. Our findings reveal that tampon proxies made of trilobal cellulose viscose fibres exhibit significantly larger pores, with a  26-32% higher pore equivalent diameter (PED), than their round-fibre counterparts, despite comparable porosity, highlighting the influence of fibre geometry on expansion and liquid uptake. Although trilobal CV tampon proxies exhibit a 41% greater expanded volume and 18.7% higher absorbency compared to round fibres, their porosity increases only moderately, underscoring the need to investigate pore structure beyond bulk metrics. Kolmogorov–Smirnov distance analyses confirm that inter-fibre differences in pore structure exceed intra-sample variations, underlining the dominant role of fibre type on absorbency. While gradients along the tampon proxy length influence local pore formation, trilobal fibre tampon proxies consistently form larger pores, enhancing their liquid absorption properties. Additionally, we observe a systematic increase in pore size from top to bottom, likely influenced by one-sided liquid application and compression effects during production. These results offer a more detailed understanding of the mechanisms governing pore formation in tampon networks and provide a basis for future simulations of liquid imbibition, ultimately contributing to optimized tampon designs

This study presents a model for predicting the tensile modulus of cellulose nanomaterial (CNM)-reinforced composites by accounting for the contributions of both the filler and the interphase network beyond the mechanical percolation onset (ϕ_p). The model links the nanocomposite modulus to the moduli and volume fractions of CNM, the percolated network, and the surrounding interphase network. To test the model, experimentally measured moduli from various nanocomposite systems are compared with predictions from parametric analyses. The results show a strong agreement between experimental and calculated values, which supports the validity of the model. Composites with a higher CNM content and a lower percolation threshold yield significantly stronger materials. For example, no reinforcement occurs when the filler volume fraction is below 0.02 and ϕ_p = 0.08; however, raising the CNM volume fraction to 0.06 and lowering ϕ_p to 0.01 increases the modulus by 300%. An interphase network modulus (E_iN) below 2 GPa does not improve stiffness, while interphase depth of 22 nm and E_iN = 12 GPa lead to a 600% increase in modulus. Therefore, a deeper and stiffer interphase network produces stronger composites. Similarly, no reinforcement is observed for CNM radii greater than 15 nm, but the modulus increases by 700% at R = 5 nm and a CNM length of 3 μm. These results indicate that thinner and longer CNMs produce stiffer nanocomposites.

The production of second-generation bioethanol from non-woody lignocellulosic feedstocks is constrained not only by biomass recalcitrance but also by the substantial energy burden of deconstruction and conversion. In this study, we compile and normalize energy and yield data from recent publications to evaluate process-level performance across pretreatment, saccharification, fermentation, and distillation stages. The overall energy consumption typically ranges between 25 and 130 kWh per kilogram of ethanol. The stage-level contributions are distributed as pretreatment (5–20%), saccharification (10–25%), fermentation (10–20%), and distillation (40–60%). Heating demand accounts for approximately 70–80% of the total, whereas non-heating electricity contributes around 20–30%. This pattern indicates that heat integration and the adoption of low-carbon steam are essential strategies for reducing thermal loads, while improvements in agitation, milling, and mixing efficiency are more effective for reducing electrical demand. Net energy ratio (NER) values remain below unity when heating loads are included, but they increase substantially when only non-heating inputs are considered, which emphasizes the critical role of heat management. The associated CO₂-equivalent emissions further confirm that distillation is the dominant hotspot. Overall, low- to moderate-temperature alkaline and hybrid pretreatments approach the efficiency frontier, while severe high-temperature routes do not necessarily deliver system-level gains. Heat integration could reduce steam demand by 20–40% and thereby improve the sustainability of non-woody lignocellulosic ethanol systems without altering relative performance trends.

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