Description of Microstructural Changes in Wheat Flour and Flour Components during Hydration by using Environmental Scanning Electron Microscopy

The initial microstructures of two wheat flours (hard wheat flour and soft wheat flour) and flour components (starch, gluten, soluble pentosans and insoluble pentosans) were observed by scanning electron microscopy (SEM) and the changes in microstructure during hydration were described using environmental SEM (ESEM). SEM images permitted observation of the classical microstructure of wheat flour particles and starch granules. The initial microstructure of the purified fractions of flour components (gluten, soluble pentosans and insoluble pentosans) seemed largely dependent on the purification techniques, and could not thus directly be used to describe their in situ behavior during flour processing. ESEM observations of wheat flours and flour components during hydration first demonstrated slight changes in surface of particles that we associated to apparent swelling effects. The formation of a continuous aqueous phase between particles was observed for long hydration times.     

In Vitro and In Silico Analysis of New n-Butyl and Isobutyl Quinoxaline-7-carboxylate 1,4-di-N-oxide Derivatives against Trypanosoma cruzi as Trypanothione Reductase Inhibitors

American trypanosomiasis is a worldwide health problem that requires attention due to ineffective treatment options. We evaluated n-butyl and isobutyl quinoxaline-7-carboxylate 1,4-di-N-oxide derivatives against trypomastigotes of the Trypanosoma cruzi strains NINOA and INC-5. An in silico analysis of the interactions of 1,4-di-N-oxide on the active site of trypanothione reductase (TR) and an enzyme inhibition study was carried out. The n-butyl series compound identified as T-150 had the best trypanocidal activity against T. cruzi trypomastigotes, with a 13% TR inhibition at 44 μM. The derivative T-147 behaved as a mixed inhibitor with Ki and Ki’ inhibition constants of 11.4 and 60.8 µM, respectively. This finding is comparable to the TR inhibitor mepacrine (Ki = 19 µM).     

A technique for defining agent-oriented engineering processes with tool support

The formalization of engineering processes is necessary for guaranteeing the quality and cost of the products involved. Agent-oriented engineering has already proposed development processes that still need to be further formalized to be applicable by non-researchers. This paper proposes a technique to instantiate processes for specific agent-oriented methodologies. This technique is based on three orthogonal views that are respectively related with lifecycles, disciplines and guidances. In addition, processes are modeled with a tool, which is automatically generated from a process metamodel inspired by the software & systems process engineering metamodel. Accordingly, engineers can choose the methodology–process pair best-suited for the characteristics of their project. The paper illustrates the approach based on the unified development process and the scrum process for the INGENIAS methodology and compares the results with other existing alternatives.     

Improvement of wood properties by impregnation with macromonomeric initiators (macroinimers)

Scotch pine, eastern spruce, and eastern beech samples sawed longitudinally were impregnated with a new type of polymerization mixture (macroinimer and styrene), leading to crosslinked block copolymers of styrene and poly(ethylene glycol). Weight gains of 36.37–91.13% were obtained after polymerization for 2 h. Water uptake of the polymerized wood was found to be 35.13–72.07% after a water soak test of 144 h. While spruce gave the highest uptake (72.07%), beech showed the lowest value (35.13%). The specimens impregnated with the mixture of macroinimer and styrene showed a water-repellent effectiveness of 35.14–58.15% after a water soaking test of 144 h. The highest values of water-repellent effectiveness were found for spruce, while the lowest values were obtained for pine. A maximum antiswell efficiency (ASE) of 42.43% was obtained for spruce, followed in order by beech and pine, respectively. The ASE value increases with an increase in wt % gain. Improvements of 19.12% in longitudinal compression and 25% in bending strength were also achieved for spruce samples with low weight percent gain. IR spectroscopy was used for chemical characterization of the wood–polymer composite. © 1993 John Wiley & Sons, Inc.     

Kinetics of wood phenolysis in the presence of HCL as catalyst

Monarch birch wood (Betula maximowiczina Regel) wastes were phenolated in the presence of HCl as a catalyst at 60–150°C for various reaction times. Typical kinetic parameters along with percent reacted wood and phenol were determined by using kinetic models. In addition, according to the transition‐state theory the activation parameters of wood phenolysis was determined. The percent reacted wood wastes depicted that about 90% of the wood could be liquefied into phenol at a temperature of 150°C. However, about 30% of phenol was found to react with wood components. The kinetic studies showed that wood phenolysis with HCl catalyst at 60–150°C obviously followed a bimolecular type of second‐order reaction. Activation energy was found to be 13.438 kJ mol^?1 from an Arrhenius plot. Furthermore, the findings related with activation enthalpy showed that the wood phenolysis had dominantly endothermic reaction nature. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1098–1103, 2002     

Sorption of copper (II) ions by pine sawdust

The sawdust of Calabrian pine was used as sorbent for the removal of Cu(II) ions from aqueous solution of copper sulfate pentahydrate (CuSO₄.5H₂O) at different concentrations, pHs and temperatures. The results showed that about 65–81% of Cu(II) ions in the solution could be adsorbed on the sawdust. The percentage of adsorped Cu(II) ions onto the sawdust increased with increasing initial concentration. Kinetic studies indicated that the sorption process followed the first order reversible kinetic model. It was also determined that the sorption process obeyed the Freundlich isotherm. Furthermore, the sorption thermodynamic was investigated in detail.