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The Tasmanian sawmilling industry has traditionally been heavily focused on the processing of mature eucalypt timbers. However, the available log supply has contained an increasingly high proportion of younger, smaller regrowth logs. In response to this change, the Tasmanian sawmilling industry carried out an experimental program aimed at determining a means of processing regrowth Eucalyptus obliqua into high quality sawn and dried timber similar to that available from mature logs. Initial investigations revealed that application of conventional processing techniques to the production of dried machined tangentially sawn (“backsawn”) 25 mm and 19 mm thick boards did not produce commercially viable results. Two possible techniques for reducing drying degrade were investigated: storing boards for some time prior to drying and periods of zero airflow applied intermittently during drying. Neither technique proved effective. Quartersawn timber was found to undergo less surface checking and endsplit than did backsawn. Thinner boards showed no decrease in drying degrade when compared to thicker boards.

The problems of making phase-pure (Hg0.7Bi0.3)Sr2(Ca1-xLax)Cu2O6+σ system for 1.0≧x≧0.0 are discussed in detail. This system with the tetragonal HgBa2CaCu2O6-type (1212) structure was found only for x=0.25, 0.5 and 0.75. The a and c lattice parameters increase with the increasing La concentration due to the decreasing in oxidation state of Cu and the replacement of smaller Ca+2 ions (1.12 A) by larger La3+ ions (1.16 A). The transition temperature Tc decreases as the La substitution parameter x increase. We observed the maximal Tc at x=0.25 with 87K and 72K for x=0.5.