Chemical changes of kenaf core binderless boards during hot pressing (I): influence of the pressing temperature condition

Self-bonding is the main factor of the performance expression of binderless boards, and therefore its clarification is considered to be an important issue. For this purpose, a series of chemical analyses were conducted on kenaf core binderless boards and their chemical changes during the hot-pressing process are discussed in this article. First of all, binderless boards were prepared from kenaf core powder at different pressing temperatures (without steam-explosion process) and were used for chemical analyses after they were reduced into powders and extracted with methanol. To investigate their chemical changes, lignin, holocellulose, and neutral sugar contents were determined, Fourier transform infrared (FTIR) spectra were recorded, and the nitrobenzene oxidation procedure was applied. As a result, it was found that parts of lignin and hemicelullose were decomposed during the hot-pressing process; however, the contribution of the resulting fractions to selfbonding was not observed. In addition, progress of condensation reactions in lignin and the formation of chemical bonds by low molecular weight conjugated carbonyl compounds in methanol extractives were observed. Thermal softening of lignin is also suggested to play an important role in the expression of board performance.     

Behavioural and physiological responses of sheep to 16 h transport and a novel environment post-transport

The effect of a novel lairage environment on the ability of sheep to recover from 16 h of transport was investigated. Sheep were transported from grass paddocks to either novel outside paddocks or inside pens, and housed groups were transported to either familiar or novel inside pens. During transport, sheep from outside paddocks lay down less than those from inside pens. In sheep transported to inside pens, those from outside paddocks spent more time lying and spent less time eating; hay and water intakes during the first 12 h post-transport were lower than those previously kept inside. There was no obvious effect of a novel environment post-transport on blood biochemistry, suggesting that the lower post-transport feed and water intakes in a novel environment did not have a significant effect on the ability of the sheep to recover from the feed and water deprivation associated with transport.