Solvent Detection and Water Monitoring With a Macroporous Silicon Field-Effect Sensor

Integration of electrical and fluidic systems for the design and fabrication of a system-on-chip (SOC) capable of sensing various liquid phase solvents is reported. A monolithic integration strategy makes use of macroporous silicon (MPS) as a gateway to interface the electrical and fluidic domains. In this application, the MPS material, acting as a sensing membrane, is used in a flow-through structure to transport an analyte from fluidic channels on one side of the chip to sensing electrodes on the other. A fluid-oxide-semiconductor interface results in the modulation of a space charge region in the semiconductor where real-time measurements are used to detect and distinguish between the presences of various solvents. The fluidic system has delivered sample volumes as small as 2 mul. Selected test solvents (i.e. acetone, ethanol, isopropyl alcohol, methanol, and toluene) have generated a measured change in capacitance up to 11%. A practical application of this sensor was demonstrated by monitoring various concentrations of isopropyl alcohol in a water supply. Undiluted samples provide characteristic responses that can be used for signature identification. The sensing device has a high degree of reusability and does not require heating or other solvent removal methods often necessitated in other sensing devices     

Experimental characterization of the flow pattern in an annular fluidized bed

The annular fluidized bed combines a long solids residence time and a good heat and mass transfer. To experimentally characterize the flow pattern in the system, pressure drop and capacitance probe measurements have been carried out under ambient conditions in two plants of inner diameters of 0.19 and 0.74 m. Depending on the interaction between gas velocity in the central jet and ratio of bubble to central nozzle diameter, the ratio of internal to external solids circulation can be regulated.     

Meerrettich und Meerrettichkonserven

Ohne Zusammenfassung     

Zur Frage des Vorkommens von Salicyls?ure in Naturweinen

Ohne Zusammenfassung     

The influence of residual stresses implicated via cure volume shrinkage on CF/VEUH—composites

This paper presents a thermal finite element analysis (FEA) of a unidirectional carbon fibre reinforced vinylester urethane hybrid matrix system. The evolution of the thermal residual stresses due to the mismatch in the coefficient of thermal expansion (CTE) of the single components in the cooling phase have been investigated. Additionally, the cure volume shrinkage was implemented into the FE-model. The model allows the transition of the homogeneous unidirectional composite material properties on a microscopic spot, where the properties of the fibres and the matrix can be considered separately. It could be shown, that the cure volume shrinkage (CVS) has a dramatic effect on the fibre/matrix interface region due to radial compression stresses along the fibre. Further, this may lead to microcracking or fibre/matrix debonding before any kind of load is applied to the material.     

The digestibility of fats—A correlation of experimental data

Summary It has been shown by statistical analysis that a positive correlation exists between digestibilities found in human adults and those found for corresponding fats in albino rats. The general limiting factor of digestibility of a fat is the amount of saturated fatty acids present, but the extent of limitation is dependent upon the adaptability of the subject. It is concluded as a general rule that the amount of saturated acids of 18 or more carbons is the chief limiting factor. This fact readily accounts for the lesser degree of correlation which exists between digestibility and melting point, the latter being partially a function of the amount of long chain saturated acids. Presented at the 37th Annual Spring Meeting of the American Oil Chemists' Society in New Orleans, La., on May 15–17, 1946.