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Radiata pine wood (W) was modified with acetic anhydride and glutaraldehyde (GA) resulting in WAc and WGA to various weight percent gains (WPGs), whereas in WAc the effect is due to grafting and in WGA, crosslinking. The heat of vaporization of bound water (BW) of the modified woods was studied by differential scanning calorimetry (DSC) and the mass loss (due to water loss) of the samples by thermogravimetry (TG). The temperature program was in both cases from 25 to 40°C with 10°C min−1. The adsorbed or condensed water in wood were observed via low-field nuclear magnetic resonance (LFNMR). At a comparable WPG level, the LFNMR analysis showed that the interaction of water with WGA was stronger than that with WAc. In both modified woods, a considerable reduction in the vaporization heat of BW was visible due to cell wall hydrophobization and bulking. The reduction of condensed water in micropores was lower for WGA than WAc, probably because BW needs more energy to evaporate from the crosslinked stiff WGA cell walls.

A facile method for the one-pot synthesis of 1,2-diarylindoles under transition-metal-free conditions is described. Cyclohexanones were used as the aryl sources via the dehydrogenative aromatization process. One C-C and two C-N bonds were selectively formed via a domino reaction. This protocol provides a convenient approach for the construction of valuable bioactive 1,2-diarylindoles from readily available cyclohexanones, α-hydroxyketones and anilines.

The effect of composition on the quenching sensitivity of Al-Zn-Mg-Cu-Zr aluminum alloys was investigated through hardness test, microstructure analysis and thermodynamic calculations. The materials involved are 7085, 7050, 7150 and 7055 aluminum alloys. The quenching sensitivity of the alloys has been evaluated by the percentage of hardness reduction after aging process. The results show that the aging hardness reductions for the alloys by air quenching are up to 8.6%, 18.4%, 21%) and 21.7%, respectively, in comparison with that by water quenching. The precipitation of 7050 and 7055 aluminum alloys is much more compared to that of 7085 aluminum alloy during air quenching process, which decreases the capability of aging hardening and causes quenching sensitivity of 7050 and 7055 aluminum alloys. The interrelation of composition, equilibrium phase and quenching sensitivity is investigated from perspective of thermodynamic calculations, and the total mole fraction of equilibrium phase during quenching process is proposed to be a criterion for evaluating the quenching sensitivity of Al-Zn-Mg-Cu-Zr series aluminum alloys.

Scots pine sapwood was treated with various concentrations of glutaraldehyde (GA) and magnesium chloride as a catalyst in aqueous solutions. The weight percent gains (WPGs) attained after leaching were 1.0%, 8.6%, 13.7%, and 21.9%, respectively. The treatments reduced the equilibrium moisture content at 90% RH up to 30% compared with the untreated controls. Capillary water uptake of wood was also restrained by GA treatment (8.6% WPG) resulting in water reduction effectiveness of approximately 50% in both radial and tangential direction after 244 h. Wood blocks treated to the highest WPG (22%) attained 70% anti-swelling efficiency (ASE). High ASE values were caused by cell wall bulking through incorporation of GA in the cell wall and as a result of reduction of the maximum degree of swelling in water, i.e., through crosslinking of cell wall polymers. During 10 water submersion and drying cycles, untreated and GA treated specimens displayed equal weight losses indicating that mainly wood constituents were washed out. These cyclic water submersion tests also caused approximately 10% reduction in ASE in samples treated to higher WPG. Magnesium chloride as a catalyst for the reaction of GA imparts wood similar water related properties as sulphur dioxide catalysis of GA treatment, but the application of MgCl2 is much easier to perform in practice.

Efficient use of timber is a vital concern problem, especially in these regions where the forestry coverage ratio is decreasing. Studies on physical modification of wood have been taken more attention due to the increasing attentions on environmental protection. Thermal modification is emphasized and developed quickly in developing countries, especially in European countries. A large number of researches have been conducted and some industrial production plants have been built. This paper reviewed the history of heat treatment, exemplifies the industrial developments in several European countries, summarized the basic principle of heat treatment and describes the environmental characteristics. The properties of heat-treated wood and its usage are also summed up.