Dendrite coherency during equiaxed solidification in binary aluminum alloys

Dendrite coherency, or dendrite impingement, is important to the formation of the solidification structure and castability of alloys. Dendrite coherency in the systems Al-xMn, Al-xCu, Al-xFe, and Al-xSi(x = 0 to 5 wt pct) has been studied by continuous torque measurement in solidifying samples. The fraction solid at the dendrite coherency point, fs*, varies with the alloy system and the solute concentration in the alloy, from 18 to 56 pct for the present alloys investigated. An increase in solute concentration decreases the coherency fraction solid,fs*. An alloy system with a large slope of the liquidus line has a high coherency fraction solid. A theoretical approach has been developed to account for the effects of the alloy system and solute concentration on the dendrite coherency in the alloy. The grain sizes of the alloys were evaluated using the parameters at coherency point.     

Effects of Drying Method, Packaging, and Storage Temperature and Time on the Quality of Dill (Anethum graveolens L.)

Sorption isotherms, color and sensory quality of the dill herb (Anethum graveolens L.) were determined over a 2-yr period in experiments investigating the effects of packaging and storage temperature and time for air-dried and freeze-dried dill. The intensity scoring of odor and taste was significantly (p < 0.01) poorer for the dried dills than for frozen dill. Drying with heated air and the subsequent deteriorative processes essentially altered the odor and taste. In the case of freeze-dried dill the storage conditions were important; when storage was at room temperature (23°C) the intensity of the odor and taste was better preserved in vacuum packages than in glass jars or paper bags.     

Microwave Heating Uniformity of Ready Meals as Affected by Placement, Composition, and Geometry

The importance of chemical and physical modifications in a ready meal on microwave heating uniformity was investigated. Experimental materials were four-component chilled ready meals which were heated in a domestic microwave oven. The experiment was set up by using 2⁵ factor design and data were evaluated by analysis of variance. Temperatures during and after microwave heating were measured. Heating uniformity could be mainly modified by arrangement and geometry of components and type of tray. In contrast, chemical modifications had no effect or some combined effects with other factors.     

Estimation of mass thickness response of embedded aggregated silica nanospheres from high angle annular dark‐field scanning transmission electron micrographs

In this study, we investigate the functional behaviour of the intensity in high‐angle annular dark field scanning transmission electron micrograph images. The model material is a silica particle (20 nm) gel at 5 wt%. By assuming that the intensity response is monotonically increasing with increasing mass thickness of silica, an estimate of the functional form is calculated using a maximum likelihood approach. We conclude that a linear functional form of the intensity provides a fair estimate but that a power function is significantly better for estimating the amount of silica in the z‐direction. The work adds to the development of quantifying material properties from electron micrographs, especially in the field of tomography methods and three‐dimensional quantitative structural characterization from a scanning transmission electron micrograph. It also provides means for direct three‐dimensional quantitative structural characterization from a scanning transmission electron micrograph.     

Equilibrium Water Content and the State of Water in Dehydrated White Cabbage

The water sorption isotherms for freeze-dried cabbage were determined at 15°C and 23°C, and the state of the water was studied using differential scanning calorimetry (DSC). The water sorption capacity of the freeze-dried cabbage depended on the temperature. The effects of free sugars were clear in both adsorption and desorption. The thermal behavior of freeze-dried cabbage was highly moisture dependent. In the capillary condensation range (>0.9 a_w) solution of low molecular components of the freeze-dried cabbage affected its freezing behavior.