Fractionating tower separates a gaseous phase into fractions. The tower operates by condensing the vapor into liquid. Towers are generally filled with packing. The fractionating tower contains horizontal steel trays for separating and collecting the liquids. At each tray, vapors from below enter perforations under the bubble caps. The latter permit the vapors to bubble through the liquid on the tray, causing some condensation at the temperature of that tray. An overflow pipe drains the condensed liquids from each tray back to the tray below, where the higher temperature causes re-evaporation. The evaporation, condensing and scrubbing operation is repeated many times until the desired degree of product purity is reached. Then side streams from certain trays are taken off to obtain the desired fractions. Products ranging from uncondensed fixed gases at the top to heavy fuel oils at the bottom can be taken continuously from a fractionating tower. Steam is often used in towers to lower the vapor pressure and create a partial vacuum.

Fractography is the detailed analysis of a fracture surface to determine the cause of the fracture and the relationship of the fracture mode to the microstructure of the material. Fractography techniques are used to identify the origin of a crack and to determine what type of loading caused the crack to initiate. These techniques are also used to establish the direction of crack propagation and the local loading mode, which drove the crack. Fractography is, perhaps, the most important analytical approach used by materials scientists in attempting to establish structure-property relationships involving strength and failure of materials.

Fracture evaluation is an integrated stress over a highly stressed region near the crack tip, is a material property independent of the loading rate. Fracture toughness can be predicted from the static toughness results. Evaluation of fractured reservoirs traditionally involves the identification and orientation of the fractures. Fractures are newly characterized by scribing only the fracture surface present along the image contact. Correcting the fracture scribe for the percentage of image coverage, a petrophysical log curve can be derived using a standard window size.

Fragment retention films enhance the protective capability of glass in a very unobtrusive manner. These films can be applied quickly and easily over existing windows for bomb blast mitigation. These films use micro thin, cross-woven layers of polyesters that are laminated together to enhance tensile strength and elongation.