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The objective of the study was to determine the factors affecting post-fermentative nutritional content resulting from soybean fermentation by Bacillus subtilis. Conditions for the nutritionally optimal fermentation of soybeans by B. Subtilis were varied to analyze the overall nutrient content change. The conditions included: (1) pH, (2) fermentation temperature, (3) fermentation time, and (4) bacterial density. Experimental results show the highest concentration of lipids at a pH 6.0, temperature of 33 °C, and 60 h fermentation time. Carbohydrates were highest at pH 7, 28 °C and 48 h, and protein content yielded highest at pH 8, 28 °C, and 60 h of fermentation. Bacterial density had no statistically significant affect on nutritional content (p > 0.05). Optimization of fermentation conditions contributes to increased biomass during fermentation to increase reaction yield of the desired product. Therefore, this research is important at the industrial level to increase production efficiency and reduce energy consumption.

Poplar (Populus adenopoda Maxim.) and radiata pine (Pinus radiata Don.) wood were treated with an aqueous solution containing styrene-acrylic copolymer (SAC) and sodium silicate (SS). The effects of this treatment on the thermal stability and combustion behavior of the wood were determined. Thermogravimetric (TG) analysis showed that treatment in the presence of SS resulted in earlier thermal degradation compared to samples untreated and treated with SAC alone. Cone calorimetry showed that treatment of wood with SAC alone resulted in increased total heat release, total smoke production, and CO and CO2 concentration. Wood treated with SAC/SS was more difficult to ignite as evidenced by longer ignition time and higher limiting oxygen index; however, the treatment did not reduce the production of smoke and carbon oxide. Scanning electron microscopy and energy dispersive X-ray analysis of residual char indicated that SS was mainly deposited in the lumina of vessel or tracheid, and SS distribution in wood was not uniform. These findings demonstrate that incorporation of SS retards the flame of SAC-treated wood; however, the fire risk is not reduced due to dense smoke and CO production.

Poplar (Populus adenopoda Maxim.) and radiata pine (Pinus radiata Don.) woods were treated with an aqueous solution containing styrene-acrylic copolymer (SAC) dispersion and sodium silicate (SS). The modifying effects on the mechanical properties of wood were investigated with 10% SAC and varying concentrations of SS. The SAC and the SS deposition occurred in the cell lumina and condensed under catalysis at elevated temperature, as evidenced by scanning electron microscopy. The wood treated with SAC and SS exhibited a moisture content about 2 times higher than that of the untreated control under 95% relative humidity due to the introduction of hygroscopic silicate. The modulus of rupture (MOR) and modulus of elasticity (MOE) in the bending, compressive strength, surface hardness, tensile strength, and shear strength of the wood were improved up to 83.9, 82.3, 72.7, 48.3, 38.4, and 53.1%, respectively. However, the impact strength decreased by 39.4% due to the treatments. Accordingly, the combined treatment with SAC/SS has a potential application in the improvement of the wood quality, but the reduction in impact strength could limit its utilization in products for which high dynamic strength is required.

To study the weld line formation of colliding flow fronts the filling of a mold cavity was simulated. The thermo-rheological findings were used to investigate the sources of weld line weakness. In this way critical areas of the interface in regard to the lack of interdiffusion and the inappropriate molecular orientation were found to be placed near the surface of the finished parts. The main source for the weld line weakness seems to be the V-notch that arises due to the poorly bonded region near the surface in combination with the large shrinkage as a result of extremely high molecular orientations induced at the end of the filling. Furthermore, the empirical knowledge was confirmed that weld lines are rather more sensitive to the local flow situation than the global processing conditions. Melt and mold temperatures can be considered to be the most important factors which influence the weld line strength.

Canopy transpiration of mature Jeffrey pine was compared in "mesic" and "xeric" microsites differing in topographical position, bole growth, and the level of drought stress experienced. Diurnal and seasonal course of canopy transpiration was monitored with thermal dissipation probes in 1999 and 2000. Mid-canopy measures of diurnal foliar stomatal conductance (gs) were taken in June and August in 1999. In early summer, there was little difference between trees in either microsite with regard to gs (55 mmol H2O m−2s−1), canopy transpiration (4.0 l h−1), and total duration of active transpiration (12 h >0.03 l h−1). In late summer, xeric trees had a lower daily maximum gs (by 30%), a greater reduction in whole canopy transpiration relative to the seasonal maximum (66 vs 79%), and stomata were open 2 h less per day than in mesic trees. Based on leaf-level gas exchange measurements, trees in mesic sites had an estimated 46% decrease in O3 uptake from June to August. Xeric trees had an estimated 72% decrease over the same time period. A multivariate analysis of morphological and tissue chemistry attributes in mid-canopy elucidated differences in mesic and xeric tree response. Mesic trees exhibited more O3 injury than xeric trees based on reduced foliar nitrogen content and needle retention in mid-canopy.

The properties of injection molded products are directly related to the microstructure which in turn strongly depends on the flow kinematics and thermal history of the polymer melt during the filling process. In this study the mold filling process has been analyzed by using an FEM-code (FIDAP) to solve the equation of continuity, momentum, and energy under transient and non-isothermal conditions. As constitutive relation for a purely viscous fluid, the Bird-Carreau and Arrhenius model was chosen. The phenomenon at the flow front, its flow kinematics, and its significant implication on the microstructure of the part have been investigated in detail. Computed particle tracking showed good agreement with experiments under real processing conditions. Furthermore, a rather simple but effective and useful method for predicting the orientation distribution in an injection molded part was proposed. It was found that the local deformation near the solid wall may be considered as the main source for a typical layer of high orientation on the surface of the part.

In polymer processing weld-lines occur when a polymer melt is separated and then reunited. The internal structure of a weld-line region is determined by the rheological state of the reunited melt streams. An experimental investigation of the region of interest within the mold is almost impossible. Thus, computer simulation is necessary to examine weld-lines. This paper presents a detailed analysis of the flow behavior at a weld-line interface which was caused by a flow obstacle. The results show a gradual increase of the velocity within a short distance behind the obstacle which coincides with a short weld-line determined by the advancement of the flow fronts obtained from conventional mold filling studies. However, based on the residence time history of the melt there is a weld-line over the full length of the part. Its formation mechanism was additionally described by experimental filling studies by the sandwich injection molding technique. In conclusion, the formation of the weld-line should be determined not only by the flow fronts, but also by the thermo-rheological history of the reunited melt streams.