Sensory evaluation of a hard white compared to a hard red winter wheat

Traditionally bread wheats grown in the USA have been hard red genotypes. Introduction of hard white genotypes provides an opportunity for the comparison of the products and evaluation of consumer acceptance. MT 7811, a hard white wheat, and ‘Norwin’, a hard red winter wheat, were grown in adjacent plots in each of two years. Grain from each was divided, with half milled into whole wheat flour (wholemeal) and the other half milled into white flour (milled flour). Breads made from wholemeal and milled flour from each wheat genotype were tested by panelists for differences. Color differences were easily detected. The Wilcoxon-Mann Whitney rank sums test was used to evaluate signal detection data. Both crust and crumb differences between the two wheats could be detected by some panelists. Differences could be detected between the two wheat types in either wholemeal or milled flour bread. Crust differences were often greater than crumb differences. Trained panelists commented on some bitterness in red wheat products and a sweetness in white wheat products.     

Extraction replication studies of near-surface microstructures in laser-drilled samples of the powder metallurgy Ni-based superalloy IN100

Hybrid extraction replication has been used to prepare TEM samples from laser-drilled coupons of the Ni-based superalloy IN100. In addition to extracting the inert carbide and boride particles, these carbon replicas reveal the microstructure of the surrounding metallic phases allowing the particle distribution to be studied. It is shown that the IN100 base metal contains large (> 100 nm) MC, M₂₃C₆ and M₃B₂ particles, consistent with previous TEM studies on this alloy. In the recast layers on the interior surfaces of the laser-drilled holes, however, dendritic micro-segregation in the supersaturated γ phase gives a cellular sub-structure, and the inert particles observed are nano-scale Ti-rich MC-type carbides at the cell boundaries. The replicas also reveal that the base metal/recast interface is abrupt. These observations illustrate the power of the hybrid replication technique for revealing variations in nano-scale features over much larger length scales (? 10 μm).     

A Sucrose‐Mediated Sol–Gel Technique for the Synthesis of MgO–Y2O3 Nanocomposites

A sucrose‐mediated aqueous sol–gel procedure was developed to synthesize MgO–Y₂O₃ nanocomposite ceramics for potential optical applications. The synthesis involves the generation of a precursor foam containing Mg²⁺ and Y³⁺ cations via the chemical and thermal degradation of sucrose molecules in aqueous solution. Subsequent calcination and crushing of the foam gave MgO–Y₂O₃ nanocomposites in the form of thin mesoporous flake‐like powder particles with uniform composition and surface areas of 27–85 m² g ^{? 1}, depending on calcination conditions. The flakes exhibited a homogeneous microstructure comprising intimately mixed nanoscale grains of the cubic MgO and Y₂O₃ phases. This microstructure was resistant to grain coarsening with average grain sizes of less than 100 nm for calcination temperatures of up to 1200°C. The results indicate that the sucrose‐mediated sol–gel process is a simple effective method for making nanoscale mixed oxides.