Technical Evaluation of Hybrid Clones of Corymbia spp. to Produce Market Pulp

This study presents hybrid clones of Corymbia spp. developed by Aperam BioEnergia as potential substitutes for Eucalyptus wood in the pulp industry. The biomass of Eucalyptus spp. was compared with that of Corymbia spp. by performing modified kraft pulping and basic density analyses. Comparisons were made by analyzing their respective mean annual increments of cellulose (MAI_cel) and specific wood consumption (SWC), estimated using a kappa number of (19 ± 1). The results showed that one of the hybrid clones (Corymbia citriodora × Corymbia torelliana, ID 4) had higher basic wood density, higher screened yield, better MAI_cel#k19, and lower SWC than the other samples, reaching values of 0.608 t/m³, 54.1%, 24.6 ADt/ha/year (i.e., air dry ton/hectare/year), and 2.74 m³/ADt, respectively. Consequently, clone ID 4 had the highest MAI_cel/SWC ratio score (8.98). Given its high forest productivity and low industrial cost compared with other samples, as well as its advantages over Eucalyptus spp. wood, we concluded that clone ID 4 has great potential as an alternative biomass for pulp production.     

Synthesis,structure and properties of the mixed-ligand tungsten(II) complex [WBr2(CO)3(tmpymt)] (tmpymt = 1,4,6-trimethylpyrimidine-2-thione)

The reaction of [{WBr(CO)₄}₂(μ-Br)₂]₂ 1 with 1,4,6-trimethylpyrimidine-2-thione (tmpymt) affords the air-sensitive complex [WBr₂(CO)₃(tmpymt)] 2. The X-ray structure of 2·C₃H₆O reveals that the geometry surrounding the tungsten(II) atom is best described as a distorted capped trigonal prism with a bromine atom Br(1) in the unique capping position. The other bromine atom Br(2), the (N,S)-chelate and one carbonyl C(41) occupy the capped quadrilateral face. The complex has been additionally characterized by IR and NMR spectroscopy. The optimized molecular structure (RHF/LanL2DZ) supports the experimental data.     

A framework for evaluating and improving requirements specifications based on the developers and testers perspective

Requirements Engineering - Requirements specifications are essential to properly communicate requirements among the software development team members. However, each role in the team has different...