作者机构：
[郭鑫; 吴义强; 李贤军] College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China;[郭鑫] College of Sciences, Central South University of Forestry and Technology, Changsha, 410004, China
通讯机构：
College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, China
关键词：
wood;water distribution;existing states
摘要：
Wood-water relationship has been studied since the beginning of wood research. With the development of new technology,vast modern analytical method are emerging,and the study of wood-water relationship is changing from macro to micro scale and from cell to molecular level. The main objective of this paper was to review the modern analytical techniques which have been applied to study the wood-water relationship. This paper was divided into four parts. Firstly, the extremely heterogeneity of the wood cell wall structure and chemical composition and the highly complex states of water were discussed,and then the distribution and existing states of water in wood was summarized as an active field of the research about wood-water relationship. Secondly,the application of four kinds of analytical techniques,such as magnetic resonance imaging(MRI),computed tomography(CT),neutron imaging(NI) and vibrational spectroscopic imaging,in the study of water distribution were summarized. Meanwhile,the advantages and limitations of these four techniques were provided. Some of the latest research progress was: Vibrational spectroscopic imaging techniques such as micro-FTIR and confocal Raman could offer visual examination and spectral information of chemical functional groups in situ,and owned high spatial resolution on the micrometer length scale. The spatial resolution of micro-FTIR imaging technique was 6.25 μm by the instrumental parameters,and the spectral changes indicated that the adsorbed water concentration was nonuniform at the cell structure level. Meanwhile,the spatial resolution of confocal Raman imaging technique was higher than 1 μm,and the spectral changes indicated that the amount of water in the cell corner(CC) was less than that in the middle layer of secondary wall(S2) throughout the entire range of relative humidity(RH) levels. Thirdly,the recent advances in the application of four kinds of analytical techniques,such as near infrared(NIR) spectroscopy,nuclear magnetic resonance(NMR),fourier transform infrared spectroscopy(FTIR) and Raman spectroscopy,were discussed in the study of existing states of water in wood. The advantages and limitations of these four techniques were also provided. Some of the latest research progress was: The micro-FTIR spectroscopy and a specially designed sample cell were used to examine the molecular association of adsorbed water with wood during adsorption process. It was confirmed that carboxyl CO,C—O groups as well as OH groups were active sites for water adsorption. Meanwhile,strongly,moderately and weakly hydrogen-bonded water molecules were identified and assigned. What's more,according to the variation trend of these hydrogen-bonded water molecules,three sections were divided for adsorption process. Furthermore,the existing states of water in each section was demonstrated as CO…(HOH) …OH or OH…(OH_2) …OH、WATER…HOH… WATER,and tetrahedral structure. Finally,some future research subjects in the research about wood-water relationship were proposed,such as applying new approaches with greater accuracy and higher resolution,developing the convincing component band analysis.
作者机构：
[Xiong Feng; Luo Yong-Feng; Liao Chun-Rong] Cent South Univ Forestry & Technol, Coll Sci, Changsha 410018, Peoples R China.;[Xiong Feng; Luo Yong-Feng; Liao Chun-Rong] Fudan Univ, Lab Adv Mat, State Key Lab Mol Engn Polymers, Shanghai 200438, Peoples R China.;[Li Xian-Jun; Wu Yi-Qiang] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410018, Peoples R China.
通讯机构：
[Luo Yong-Feng] C;[Luo Yong-Feng] F;Cent South Univ Forestry & Technol, Coll Sci, Changsha 410018, Peoples R China.;Fudan Univ, Lab Adv Mat, State Key Lab Mol Engn Polymers, Shanghai 200438, Peoples R China.
关键词：
Conductive polymer;Fiber;Supercapacitor;Solar cell;Fibrous energy device
摘要：
Conductive polymers implemented in fibrous energy devices have drawn considerable attention because of their economic importance, good environmental stability, and electrical conductivity. Conductive polymers demonstrate interesting mechanical, electronic, and optical properties, controllable chemical and electrochemical behavior, and facile processability. This review elaborates on the latest research in conductive polymers in fibrous energy devices, such as fibrous supercapacitors, fibrous solar cells, and fibrous integrated energy devices. The performance requirements of these fibrous energy devices, with specific reference to related materials, fabrication techniques, fiber structure, and electronic transport as well as mechanical functionality, are also reviewed in this paper.
作者机构：
[Li, Xingong; Li, Yun; Wu, Yiqiang; He, Xia; Cheng, Xiyi; Li, Xianjun] Cent South Univ Forestry & Technol, Mat Sci & Engn Coll, Changsha 410004, Hunan, Peoples R China.;[Liu, Dandan] Nanjing Forestry Univ, Coll Furniture & Ind Design, Nanjing 210037, Jiangsu, Peoples R China.;[Huang, Qiongtao] Yihua Enterprise Grp Co Ltd, Yihua Timber Ind, Shantou 515834, Guangdong, Peoples R China.
通讯机构：
[Li, Xianjun] C;Cent South Univ Forestry & Technol, Mat Sci & Engn Coll, Changsha 410004, Hunan, Peoples R China.
关键词：
Dimensional stability;Energy storage and saving;Polyethylene glycol (PEG);Thermal properties;Wood
摘要：
Green fir wood (Pseudotsuga menziesii) was modified with polyethylene glycol (PEG) to produce wood composites for energy storage and conversion. The PEG-modified wood composites were evaluated based on their dimensional stability, durability, and thermal properties by various analytical methods. The differential scanning calorimetry (DSC) results showed the melting temperature and the latent heat of the phase change material (PCM) composite were 26.74 °C and 73.59 J/g, respectively. Thermal cycling tests and thermogravimetric analysis confirmed the composite exhibited good thermal stability, reliability, and chemical stability. All treated specimens were free from noticeable defects, and the addition of a surface varnish coating prevented PEG from leaching. The PEG-modified composites exhibited improved dimensional and thermal performance, which makes this material a potential candidate for economical and green, lightweight building materials.
作者机构：
[Quan, Peng; Xie, Jie; He, Xia; Cheng, Xiyi; Xu, Kang; Li, Xianjun] Cent South Univ Forestry & Technol, Mat Sci & Engn Coll, Changsha 410004, Hunan, Peoples R China.;[Cai, Zhiyong] USDA, Forest Serv, Forest Prod Lab, Madison, WI 53726 USA.
通讯机构：
[Li, Xianjun] C;Cent South Univ Forestry & Technol, Mat Sci & Engn Coll, Changsha 410004, Hunan, Peoples R China.
关键词：
Chemical composition;Microstructure;Peanut hull particleboard;Physical and mechanical properties;Polymeric diphenylmethane diisocyanate;Urea-formaldehyde
摘要：
Peanut hull residues were considered for the manufacturing of particleboards. Various concentrations of two types of adhesive-polymeric diphenylmethane diisocyanate (MDI) and urea-formaldehyde (UF)-were separately combined with four types of peanut hull particles (fine, mixed, coarse particles, and peanut hull powder) to manufacture particleboards with a certain target density. The confidence level of the effect of the selected production parameters on the physical and mechanical properties of the panels was evaluated. The results showed that increasing the adhesive mass percentage significantly improved the dimensional stability of the boards. A better mechanical performance was achieved for the MDI-bonded boards compared with the UF-bonded boards. Superior bonding between the MDI adhesive and the peanut hulls with different particle geometries was also observed; the peanut hull powder and coarse particles were unsuitable for the manufacturing of panels, due to the risk of an internal blowout. The water resistance of the panels was poor, whereas the mechanical strength of the peanut hull particleboard met the class M-1 requirement of the ANSI A208.1 (2009) standard for wood particleboard.
作者机构：
[李贤军; 夏燎原; 吴义强] College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China;[胡云楚] College of Science, Central South University of Forestry and Technology, Changsha, 410004, China;[黄琼涛] Guangdong Yihua Timber Industry Corporation Limited, Shantou, 515834, China
通讯机构：
[Li, X.] C;College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, China
期刊：
建筑材料学报,2016年19(5):860-865 and 882 ISSN：1007-9629
通讯作者：
Wu, Yiqiang(wuyq0506@126.com)
作者机构：
[李新功; 吴义强; 张新荔; 朱晓丹; 左迎峰; 李贤军] College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
通讯机构：
College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, China
作者机构：
[龙柯全; 吴义强; 肖俊华; 李贤军; 左迎峰] College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, Hunan 410004, China
通讯机构：
[Wu, Y.] C;College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, Hunan, China
作者机构：
[Qing, Yan; Wu, Yiqiang; Liu, Liu; Tian, Cuihua; Yan, Ning; Li, Xianjun; Li, Lei] Cent South Univ Forestry & Technol, Coll Mat Sci & Technol, Changsha, Hunan, Peoples R China.;[Qing, Yan; Wu, Yiqiang; Li, Xianjun] Cent South Univ Forestry & Technol, Hunan Prov Collaborat Innovat Ctr High Efficiency, Changsha, Hunan, Peoples R China.;[Yan, Ning] Univ Toronto, Fac Forestry, Toronto, ON M5S 1A1, Canada.
通讯机构：
[Qing, Y; Wu, YQ] C;Cent South Univ Forestry & Technol, Coll Mat Sci & Technol, Changsha, Hunan, Peoples R China.;Cent South Univ Forestry & Technol, Hunan Prov Collaborat Innovat Ctr High Efficiency, Changsha, Hunan, Peoples R China.
摘要：
To overcome the poor mechanical strength of thermosensitive hydrogels, cellulose nanofibril (CNF) was used as a reinforcing agent for the preparation of PEG-based thermosensitive hydrogels through radical copolymerization. The maximum bloom and rupture strength of the hydrogel were increased respectively with 37.7% and 52% at CNF content of 0.35 wt%. The dynamic rheological properties further confirmed that CNF played a significant role in the improvement of mechanical strength, especially in elasticity. Due to abundant hydroxyl groups exposed on the surface of CNFs, the obtained hydrogels exhibited a decreasing equilibrium swelling ratio (ESR) and deswelling rate in comparison with untreated hydrogels. However, the water retention ratio (WRR) increased when CNF content increased. In addition, both treated and untreated thermosensitive hydrogels possessed continuous volume phase transition with temperature ranging from 0 to 70 °C. Combined with SEM and ATR-FTIR tests, it was indicated that CNFs contributed to the formation of hydrogen bonding between the copolymer matrix and a tight physical lock by means of an entanglement effect. These composite hydrogels are considered as promising candidates in various potential applications of soft actuators, biosensors, artificial muscles and drug delivery.
作者机构：
[谢力生; 刘佳权; 周先雁; 乔鹭婷; 李贤军] College of Material Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
