摘要：
The long-term protection of bamboo against mold fungi remains a challenge in anti-mold technology, primarily due to the abundance of nutrients within bamboo cell lumens and the poor permeability of bamboo. This study aimed to enhance the effectiveness of organic compound biocide in the long-term protection of bamboo against mold fungi through bioincising pretreatment with Trametes versicolor. The results showed that bamboo pretreated with bioincising exhibited long-term mold resistance with an efficacy of 100 % in both 20-week laboratory and 3month outdoor tests. During T. versicolor bioincising, the fungal hyphae invaded the interior of the bamboo, leading to a notable 56.6 % increase in biocide uptake while causing an 8 % reduction in mass loss. Furthermore, bamboo pretreated with T. versicolor exhibited a reduction in both starch and reducing sugar contents, and a slight decrease in lignin and cellulose contents. These findings suggested that the improved long-term mold resistance was primarily due to the consumption of nutrients within the cell lumen and increased absorption of organic biocide by T. versicolor bioincising. This study highlighted the use of bio-pretreatment to improve the long-term mold resistance of bamboo, thus prolonging the durability of bamboo-based products.
摘要：
Transformation of biomass wastes or residues into functional carbon materials is one of the main approaches to improve their added value and utilization rate. In this work, an example of discarded bamboo fibers was used to fabricate trimetallic functionalized 1D carbon composite with excellent electromagnetic wave (EW) absorption performances, via a simple solvothermal-carbonization method. When the thickness is below 2.0 mm, the composite has a minimum reflection loss (RLmin) of -61.6 dB and a specific RL value of -253 dB mg-1 mm-1, as well as an effective absorption band of 5.4 GHz at a low mass loading of 15 wt%. Such good performances are attributed to the synergetic effect of dielectric loss from bamboo fiber carbon and magnetic loss from Fe-Co-Ni interaction that greatly improved the impedance matching. In addition, bamboo fibers with rough surface could endow ample core-shell FeCoNi nanoparticles to uniform embed, which brings large number of interfaces and defects for the composite to enhance the electromagnetic loss capacity. This work provides a trimetallic compositing idea and a sustainable design approach for using biomass wastes to produce stable and efficient EW absorption materials.
期刊：
International Journal of Biological Macromolecules,2024年258(Pt 2):128975 ISSN：0141-8130
通讯作者：
Yang, Xi;Li, XJ
作者机构：
[Fan, Shutong; Yang, Xi; Li, Xianjun; Yang, X; Li, XJ] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;[Gao, Xun] Wenzhou Univ Technol, Coll Architecture & Energy Engn, Wenzhou 325006, Peoples R China.
通讯机构：
[Yang, X; Li, XJ ] C;Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.
关键词：
Chinese fir;Flame retardant;Phytic acid;Thermal stability;Zinc phytate
摘要：
To be suitable for certain construction and furniture applications, wood must be treated with a flame retardant and impregnating flame retardants into the cellulose lumens of wood is an effective flame retardant method. Phytic acid, the main storage form of phosphorus in various plant tissues, is an inexpensive, and non-toxic biomaterial that shows potential applications as an environmentally friendly bio-based flame retardant. In this study, phytic acid and zinc phytate were used to impregnate delignified wood under vacuum and pressure, which greatly enhanced the flame retardancy and smoke suppression properties of Chinese fir, while still maintaining its original texture. Phytic acid and zinc phytate were hydrogen-bonded to cellulose in wood. Phytic acid and zinc phytate were hydrogen-bonded to cellulose in wood. The results showed that the total heat release (THR) of Chinese fir treated with zinc phytate decreased from 55.66MJ/m(2) to 5.90MJ/m(2), and a compact carbonized protective layer was quickly formed on the surface of Chinese fir after ignition. Thermogravimetric analysis (TGA) showed that the char yield of Chinese fir treated by the flame retardant was 177.6% higher than that of untreated wood. This study provides an efficient, sustainable, and economical method to prepare Chinese fir with excellent flame retardancy and thermal insulation performance.
摘要：
Strong, lightweight, and shape-memory cellulose aerogels have great potential in multifunctional applications. However, achieving the integration of these features into a cellulose aerogel without harsh chemical modifications and the addition of mechanical enhancers remains challenging. In this study, a strong, lightweight, and water-stimulated shape-memory all-cellulose aerogel (ACA) is created using a combination strategy of partial dissolution and unidirectional freezing from bamboo. Benefiting from the firm architecture of cellulose microfibers bridging cellulose nanofibers /regenerated cellulose aggregated layers and the bonding of different cellulose crystal components (cellulose I beta and cellulose II), the ACA, with low density (60.74 mg cm-3), possesses high compressive modulus (radial section: 1.2 MPa, axial section: 0.96 MPa). Additionally, when stimulated with water, the ACA exhibits excellent shape-memory features, including highly reversible compression-resilience and instantaneous fold-expansion behaviors. As a versatile scaffold, ACA can be integrated with hydroxyapatite, carboxyl carbon nanotubes, and LiCl, respectively, via a simple impregnation method to yield functionalized cellulose composites for applications in thermal insulation, electromagnetic interference shielding, and piezoresistive sensors. This study provides inspiration and a reliable strategy for the elaborately structural design of functional cellulose aerogels endows application prospects in various multifunction opportunities. A combination strategy of partial dissolution and unidirectional freeze is developed for the fabrication of strong, lightweight, and shape-memory all-cellulose aerogel with the unique anisotropic structure of cellulose microfibers bridging nanofibers/regenerated cellulose aggregated layers. As a versatile scaffold, the aerogel holds great promise for applications in thermal insulation, electromagnetic interference shielding, and piezoresistive sensors.image
期刊：
Wood Material Science & Engineering,2023年18(5):1641-1649 ISSN：1748-0272
通讯作者：
Kang Xu<&wdkj&>Xianjun Li
作者机构：
[Ge, Yanglin; Lu, Tong; Ren, Yiming; He, Mingyun; Xu, Kang; Li, Xianjun; Zhou, Chenfei] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha, Peoples R China.
通讯机构：
[Kang Xu; Xianjun Li] C;College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China<&wdkj&>College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China
关键词：
Moisture content;bamboo slab density;bamboo slab thickness;temperature distribution;vapor pressure distribution
摘要：
Bamboo scrimber was made by "hot in-cold out" hot-pressing with hot parameters of 5 MPa, 150 degrees C and 40-180 min. The variation of temperature and vapor pressure were investigated during hot-pressing of bamboo slabs with various initial moisture content (IMC; 5, 10, 15, and 20%), slab target density (TD; 0.9, 1.0, 1.1, and 1.2 g/cm(3)), slab target thickness (TT; 15, 30, 45, and 60 mm) using thermocouple sensors and a self-made press-monitoring system. The results showed obvious stages in the temperature and vapor pressure behavior of bamboo slabs during hot-pressing. IMC showed a limited effect on temperature but an obvious increase in vapor pressure. TD and target TT exhibited good linear relationships with the time to reach 120 degrees C in the core layer, suggesting this can be used as an indicator of hot-pressing time. However, both TD and TT correlate less well with the vapor pressure, which might reflect differences in the size or fluffing degree of bamboo bundles.
作者机构：
[Fan, Shutong; Li, Xianjun; Li, XJ] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;[Gao, Xun] Wenzhou Univ Technol, Coll Architecture & Energy Engn, Wenzhou 325006, Peoples R China.;[Pang, Jiuyin] Beihua Univ, Key Lab Wooden Mat Sci & Engn Jilin Prov, Jilin 132013, Peoples R China.;[Liu, Guanlin] State Grid Longjing Power Supply Co, Longjing 133400, Peoples R China.
通讯机构：
[Gao, X ] W;[Li, XJ ] C;Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;Wenzhou Univ Technol, Coll Architecture & Energy Engn, Wenzhou 325006, Peoples R China.
关键词：
preservative performance;pine wood;nano-xylan;high temperature and high-pressure steam;vacuum impregnation
摘要：
This study used environmentally friendly nano-xylan to enhance the drug loading and preservative performance (especially against white-rot fungi) of pine wood (Pinus massoniana Lamb), determine the best pretreatment, nano-xylan modification process, and analyze the antibacterial mechanism of nano-xylan. High-temperature, high-pressure steam pretreatment-assisted vacuum impregnation was applied to enhance the nano-xylan loading. The nano-xylan loading generally increased upon increasing the steam pressure and temperature, heat-treatment time, vacuum degree, and vacuum time. The optimal loading of 14.83% was achieved at a steam pressure and temperature of 0.8 MPa and 170 °C, heat treatment time of 50 min, vacuum degree of 0.08 MPa, and vacuum impregnation time of 50 min. Modification with nano-xylan prohibited the formation of hyphae clusters inside the wood cells. The degradation of integrity and mechanical performance were improved. Compared with the untreated sample, the mass loss rate of the sample treated with 10% nano-xylan decreased from 38 to 22%. The treatment with high-temperature, high-pressure steam significantly enhanced the crystallinity of wood.
作者机构：
[He, Xia] College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China;[Deng, Layun] State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha 410004, China;[Li, Xiazhen] College of Mechanical and Electrical Engineering, Hunan City University, Yiyang 413000, China;Author to whom correspondence should be addressed.;[Li, Xianjun] College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>Author to whom correspondence should be addressed.
通讯机构：
[Xianjun Li] C;College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
In this work, a strategy for hybrid treatment was proposed, aiming to present a hybrid impregnation agent including lignin-derived resin (LR) and surface-modified montmorillonite (GMMT) to treat fast-growing poplar wood. The treating agents could penetrate the wood, fill the cavities of the wood interior, and strengthen the cell wall structure. The optimal WPG of 36.2% was obtained upon the response surface methodology (RSM) at the conditions of 34% LR, 1.8% GMMT, 1.2 MPa impregnation pressure, and 99 min impregnation time. The density, water uptake (WU), modulus of rupture (MOR), modulus of elasticity (MOE), and compressive strength (CS) of the samples were tested to evaluate the enhancement of the physical and mechanical properties. In addition, these samples were investigated via cone calorimeter (CONE), Fourier Transform Infrared spectrometer (FTIR), and X-ray diffraction (XRD). The results showed that the density of the treated samples increased significantly up to 0.72 g/cm(3). Compared with 134.8% of the control, the WU of the treated wood sample could decrease to 60.3%. In addition, the MOR and MOE of the resulting samples reached up to 131.8 MPa and 18.14 GPa, respectively, which were 62.3% and 77.7% higher than the control. Notably, the CS was 84.7 MPa with an increase of up to 94.7%. Moreover, the peak heat release rate (HRR) of the treated sample was obviously reduced to 231.33 kW/m(2), a decrease of 17.5% compared to the control (271.71 kW/m(2)).
期刊：
Wood Science and Technology,2023年57(2):345-357 ISSN：0043-7719
通讯作者：
Xianjun Li
作者机构：
[Yang, Xi; Li, Xianjun; Pang, Xiaona] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, 498 Shaoshan South Rd, Changsha 410004, Peoples R China.;[Liu, Xinge; Yang, Shumin] Int Ctr Bamboo & Rattan, Dept Biomat, Key Lab Bamboo & Rattan Sci & Technol State Forest, Beijing 100102, Peoples R China.
通讯机构：
[Xianjun Li] C;College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, China
摘要：
The native pore structure and characteristic are the basis for studying the permeability, pretreatment and further processing of bamboo. Herein, the porosity, surface area, pore volume and pore size distribution of moso bamboo and their radial variabilities were investigated by a combination of mercury intrusion porosimetry (MIP), nitrogen adsorption and scanning electron microscopic image analysis. Bamboo has a wide porosity range (48 similar to 70%) that exhibits a quadratic polynomial relation to the radial position, and parenchyma tissue shows higher surface porosity (around 71%) compared to vascular bundles (50.5 similar to 20.3%). The cell wall pores uncovered by MIP and N-2 adsorption display the meso- to macropores abundant characteristics and the mesopores account for 54.5 similar to 62.4%. Different radial samples demonstrate the similar pore size distributions but variable volumes and surface areas (85.3 similar to 88.2 m(2)/g). The outer part of bamboo has these values smaller than that of middle and inner samples, revealing a more compact structure. The present work gives an in-depth view on bamboo pore structure and radial heterogeneity, which could provide the basis for pretreatment and subsequent development of value-added bamboo products.
作者机构：
[徐康; 张晓萌; 李中昊; 周川玲; 吕建雄; 李贤军; 吴义强] College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha;410004, China;Zhejiang Academy of Forestry, Hangzhou;310023, China;Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing
通讯机构：
College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, China
期刊：
Science of Advanced Materials,2022年14(8):1369-1377 ISSN：1947-2935
作者机构：
[Li, Xian-jun; Wang, Yong] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.;[Deng, La-yun; Li, Yong-jin; Wu, Hong; Wang, Yong] Hunan Acad Forestry, Changsha 410004, Hunan Province, Peoples R China.;[Yang, Shou-lu] Guizhou Acad Forestry, Guiyang 550005, Guizhou Provinc, Peoples R China.
关键词：
Poplar Wood;Mechanical Performance;Synergistic Effect;Water Resistance;Thermal Stability;Delivered by Ingenta
摘要：
This study proposes a green and facile method by combining furfuryl alcohol (FA) and organic montmoril-lonite (OMMT) to solve the undesirable intrinsic properties and improve the performance of fast-growing wood. Wood/FA/OMMT nanocomposites (WPNCs) were fabricated by vacuum-pressure impregnation of FA/OMMT solution into wood cavities with the following in situ polymerization to generate an interpenetrating network structure in cell structures. The FA and OMMT were distributed inside cell walls and transition areas between cell walls and cell lumens through SEM-EDXA and CLSM analyses. The resultant WPNCs had enhanced dimensional stability and water resistance ability. The incorporation of FA and OMMT could further improve the mechanical performance and the thermal stability of WPNCs. Therefore, FA/OMMT could synergistically enhance the performance of fast-growing wood.
摘要：
With the desire of promoting the further development of wood production, Soy protein-based adhesives (SPs) have been modified to overcome the defect of poor water resistance in the existing reports. Herein, the microcrystalline cellulose (MCC) was grafted by 3-Glycidyloxypropyltrimethoxysilane (KH560) to obtain IP: 182 75 148 10 On: Fri 12 Aug 2022 10:57:13 a modified microcrystalline cellulose (MMCC). The soybeaflour wamixed with ethylene glycol diglycidyl Copyright: American Scien ific Publis hers ether/diethylenetriamine (EGDE/DETA) and thMMCC to prpare the modified soy protein-based adhesive. De vered by ngenta The results showed that the adhesive with multiple additives had a better performance due to the interpenetrating network structure of soy protein molecules. The contact angle (CA) increased from 33.97 degrees to 58.88 degrees. The wet bonding strength increased to 0.99 MPa. Consequently, the objective of this study is to provide a new strategy for manufacturing a new environmental adhesive.
作者机构：
[杨喜; 曹敏; 简煜; 庞晓娜; 李贤军] College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha;410004, China;[杨喜; 曹敏; 简煜; 庞晓娜; 李贤军] 410004, China
通讯机构：
[Li, X.] C;College of Materials Science and Engineering, China
摘要：
Biomass porous carbon possessing hierarchical pores and abundant heteroatoms has emerged as a sustainable and cost-effective functional material. Herein, a green cellulose solvent was employed as the activation agent and nitrogen source to obtain this distinctive structure from bamboo cellulose fibers. With the assistance of thermal treatment, the solvent could fully infiltrate into cellulose structure of raw material and result in the cellulosic structure damage, forming ultimately the three-dimensional conductive network, hierarchical pores, as well as high heteroatom doping (8.43 at%). Benefited from the unique structure, the obtained porous carbon as the supercapacitor electrode showed excellent capacitive performance (280 F/g at 0.3 A/g), good rate capability and cyclic stability. Moreover, influences of hydrothermal temperature on cellulose structure, pore formation, and the resultant supercapacitor performance were demonstrated. This green strategy shows potential for producing hierarchical porous carbon with high heteroatoms from biomass resources.
摘要：
Response surface methodology (RSM) was used to optimize the preparation conditions of nano-hybrid wood/polymer composites with montmorillonite (MMT) and furfuryl alcohol (FA). The effects of MMT amount, impregnation pressure and impregnation time on weigh percent gain (WPG) of treated samples were evaluated with Box-Behnken design (BBD) of a 3-level-3-factor from RSM. The predictive model for the response was extremely significant (p < 0.01). The determination coefficient (R-2) and the adjusted determination coefficient (root R-2 ) of this model were 0.9651 and 0.9203, respectively. The optimal preparation conditions obtained by RSM design with the assistance of Design Expert were determined as follows: 4 wt% MMT amount, 0.8 MPa impregnation pressure, and 80 min impregnation time. It could be concluded from the SEM images that MMT and FA coated the cell walls and filled cell lumens. Moreover, the thermal stability was also investigated. The effects of preparation conditions were further validated by analyzing the water uptake ratio (WU), modulus of elasticity (MOE) and modulus of rupture (MOR) of the pristine samples and the treated samples prepared under optimized conditions.
作者机构：
[曹敏; 邓雨希; 全鹏; 徐康; 杨喜; 李贤军] College of Materials Science and Engineering, Central South University of Forestry Technology, Changsha;410004, China;[曹敏; 邓雨希; 全鹏; 徐康; 杨喜; 李贤军] 410004, China
摘要：
Manipulation on pore structure is an effective approach to reinforce electromagnetic wave absorption function of carbon-based materials. Herein, ultralight carbon materials with hierarchical pores are facilely synthesized from the waste reed through one-step calcination process. Through regulating the porous structure and complex permittivity of pure carbon, it can be found that the strongest microwave absorption peaks appear in different frequency range and shift from a high frequency of 17.2 GHz to a low frequency of 5.1 GHz. The unique cellular structure with hollow microchannels contributes to the conduction loss and multiple scattering, while the formation of abundant nanopores enhances the polarization loss, resulting in excellent microwave absorption performance. Under a low filler loading of 10 wt.%, the remarkable reflection loss reaches -63.9 dB at 10.8 GHz, and the effective absorption bandwidth as wide as 7.6 GHz. Moreover, by controlling the thickness (1.8-5.5 mm), the absorption bandwidth less than -20 dB ranges from 4.6 GHz to 18 GHz. This work offers the relevance of porous structure and wave absorption properties of pure carbon materials and provides a feasible strategy to design absorbers with efficient microwave absorption performance.
