Cornelis F. De Hoop

Isolation and characterization of cellulose nanofibers from bamboo using microwave liquefaction combined with chemical treatment and ultrasonication

Cellulose nanofibers were successfully isolated from bamboo using microwave liquefaction combined with chemical treatment and ultrasonic nanofibrillation processes. The microwave liquefaction could eliminate almost all the lignin in bamboo, resulting in high cellulose content residues within 7min, and the cellulose enriched residues could be readily purified by subsequent chemical treatments with lower chemical charging and quickly. The results of wet chemistry analyses, SEM images, and FTIR and X-ray spectra indicated the combination of microwave liquefaction and chemical treatment was significantly efficient in removing non-cellulosic compounds. Ultrasonication was used to separate the nanofibrils from the purified residues to extract nanofibers. The TEM images confirmed the presence of elementary fibrils, nano-sized fibril bundles, and aggregated fibril bundles. As evidenced by the TGA analysis, cellulose nanofibers isolated by this novel technique had high thermal stability indicating that the isolated nanofibers could possibly be applied as reinforcing elements in biomaterials.

Dilute Alkali and Hydrogen Peroxide Treatment of Microwave Liquefied Rape Straw Residue for the Extraction of Cellulose Nanocrystals

Microwave-assisted liquefaction of rape straw in methanol was conducted to collect the liquefied residues for the extraction of cellulose nanocrystals (CNCs). The liquefied residue with content of 23.44% from 180°C/7.5źmin was used to fibrillate CNCs with dilute alkali (2% NaOH) and hydrogen peroxide (5% H2O2) treatments, followed by ultrasonication for 15źmin. The FT-IR spectra and SEM images revealed that the liquefied residue from 180°C/7.5źmin exhibited a relatively homogeneous texture and a huge surface with cellulose as core structure. The retained hemicelluloses and other impurities in the liquefied residue were eliminated by 2% NaOH treatment, and the surface and accessibility of the alkali treated sample were significantly increased by 5% H2O2 treatment. The TEM images confirmed the CNCs had an average diameter of 12.59źnm. The CNCs had good thermal stability with a maximum weight loss temperature of 376.5°C.

Anatomical characteristics and physical–mechanical properties of Neosinocalamus affinis from Southwest China

The anatomical characteristics and physical–mechanical properties of Neosinocalamus affinis culms from three locations in China were investigated. The fiber percentage, length, wall thickness, basic density, and mechanical properties all increased with culm height, while the fiber lumen diameter and volume shrinkage showed an inverse trend. The site had significant influence on the fiber percentage and physical–mechanical properties, while the influence on vascular bundle density and fiber morphology was not significant. Therefore, the influences of site on bamboo properties may be taken into consideration for constructional utilization, and those for pulping may be ignored.

A quarter of a century with the International Journal of Forest Engineering

The 1980s were very active years for the world’s forest harvesting industry. Many new machines and logging systems were being introduced, particularly in North America and Scandinavia. However, the forest engineering community had no dedicated scientific journal in which to report the results of their research, and to disseminate these findings back to the industry. Thanks to the initiative of faculty and staff in the Department of Forest Engineering, University of New Brunswick, Canada, and a dedicated international group of editorial board members, the first issue of the Journal of Forest Engineering was published in July 1989, under the editorship of Jeremy Rickards. Thus, this year is the 25th anniversary of the first international peer-reviewed scientific journal dedicated entirely and solely to forest engineering. The number of contributors and subscribers to the journal expanded rapidly and in 2000 International was added to the title, recognizing subscribers and contributors on all continents. Much has happened during the journal’s first quarter of a century, both in terms of how forest operations are conducted as well as of research focus and the conditions for the researcher’s publishing in the journal. These developments unfold quite clearly when following the happenings of and the publications in the IJFE. Here we, all five of the editor-in-chiefs during the 25 years, summarize these developments, as well as provide behind-the-scene facts. Naturally we also provide a view on the future of IJFE and on forest engineering research in general.