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In order to fabricate green composites without the emission of toxic volatile compounds, wood fiber (WF) biocomposites reinforced with polylactic acid (PLA) were prepared utilizing the traditional hot-press manufacturing process. The effect of adding ammonium lignosulfonate (AL) on the mechanical and dimensional properties of the biocomposites was investigated. When the mass ratio of WF to PLA is 7:3 and the AL mass percentage is in the range from 1 to 20 wt%, the modulus of rupture of the WF/PLA/AL composites ranged from 21.95 to 36.96 MPa, the modulus of elasticity ranged from 3078.6 to 4157.8 MPa and the internal bonding strength ranged from 0.69 to 1.71 MPa, which showed a 4.0–75.1% increase in modulus of rupture, a 3.5–39.8% increase in modulus of elasticity and a 21.5–201.2% increase in internal bonding strength compared to the corresponding WF/PLA composites due to the reinforcing effect of AL. However, AL negatively affected the dimensional properties of the biocomposites. The thickness swell of the WF/PLA/AL composites ranged from 18.7 to 43.5% and the water absorption ranged from 47.1 to 78.9%. The thickness swell, water absorption and contact angle of the WF/PLA/AL composites increased with the AL mass percentage due to its high hydrophilicity, resulting in a 1.1–132.6% and a 3.4–67.4% increase in thickness swell and water absorption, respectively. AL had a positive effect on the crystallinity of the biocomposites due to its good surface activity as long as the AL mass percentage was below 20 wt%. The fractured surface of the WF/PL/AL composites clearly showed that a strong bond (mechanical interlocking and/or chemical bonding) exists at the interface resulting in an effective stress transfer.

Modified ammonium lignosulfonate (MAL) and polyethylenimine (PEI) were combined and used as a binder in the manufacture of a wood-based green composite. The effects of hot pressing temperature (150 oC to 190 oC), hot pressing time (3 min to 11 min), binder content (10 wt.% to 30 wt.%), and MAL/PEI weight ratio (1:1 to 1:9) on the physico-mechanical properties of the composites were investigated. The composites met the mechanical property requirements for furniture grade medium density fiberboard (MDF-FN REG) under the following parameters: hot pressing temperature of 170 oC, hot pressing time of 7 min, binder content of 20 wt.%, and MAL/PEI weight ratio of 7:1. Under optimum processing, although the X-ray diffraction analysis showed that the addition of either unmodified ammonium lignosulfonate (UMAL) or MAL did not change the crystalline structure, this addition markedly improved the relative crystallinity of the composites in comparison to that of pure wood fiber. The DMA results indicated that the MAL/PEI composites had higher storage modulus and tanδ values than did the UMAL/PEI composites. Moreover, SEM analysis showed that the MAL/PEI composites had better bonding strength characteristics than did the UMAL/PEI composites.

The paper which based on the idea of “low carbon economy” scanned the wood carbon storage function and analyzed the wood carbon storage from the present research situation of home and abroad. And it put forward the research content and specific research methods of the wood carbon storage. Finally it summarized the expected achievement and development trend of studying the wood carbon storage under the construction of low carbon economy. The research will have the practical directive function about realizing the energy saving and emission reduction of carbon dioxide, transforming the mode of economic development and improving the wood’s carbon storage.

In order to explore the factors of fraxinus mandshurica veneer dye-uptake, the discourse made use of reactive dyes. The result showed that significant effects of fraxinus mandshurica veneer dye uptake are reactive dye concentration, dyeing temperature, dyeing time and sodium chloride concentration. The artificial dyeing technology of fraxinus mandshurica was defined finally. Using reactive dyes, reactive red X-3B 10 g/L, temperature 95 °C, the dyeing time 240 min, sodium chloride 30 g/L. The study provided a theory gist and a practical guidance role for imitation precious wood.

In our research, a commercial poly (lactic acid) (PLA) film was used in combination with wood fiber matrix to generate biodegradable composites by a film stacking technique and hot-press. The results showed the flexural properties and water resistance increased with the increasing of PLA addition. Silane-treated wood fiber composites significantly improved the flexural properties compared to untreated composites. In experiment range, the physical and mechanical properties of composites were better in higher hot-press temperature. The optimal parameters are determined by PLA addition 20%, silane addition 3%, the hot-press temperature 190°C, the hot-press time 10min.Under these parameters, the flexural properties of composites exceeded the requirement of the outdoor boards’ standard, but the water resistance was a little low.

The tests on physical and mechanical properties of fiberboards made of wood fiber with ammonium lignosulphonate/urea as filling material are performed according to requirement of EU standards EN 622-2-2004 "Fibreboard-Specifications Part 2: Requirements for hardboard" reveal the reaction mechanism of formaldehyde-free fiberboards with ammonium lignosulfonate /urea as filling material through analysis of characteristics of chemical reactions on ammonium lignosulfonate and urea by FTIR and the chemical reaction analysis of C atom by ESCA. The results show that physical and mechanical properties of fiberboards with ammonium lignosulphonate/urea as filling material have reached the requirement of EU standards EN 622-2-2004, the forming of furan resin, the results of reaction between urea and furfural substances is main reason for the better physical and mechanical properties of lignin-based formaldehyde-free fiberboard.

The changes of the surface colors and chemical constituents of Mongolian Scotch pine treated by UV light were investigated by spectrophotometer and FTIR followed by acid pretreatment. The results show that the changes of the surface colors are related to carbonyl, aromatic nucleus, arone, Ar-OH, paraquinones, ortho quinine and so on in the course of UV irradiation. Acid promotes photocycloaddition and plays a hyperchromic effect.