Loose wrapping

Spiral-wound loose wrap or full-fit modules (FFM) are used in many pharmaceutical systems because there are no brine seals to prevent the by-pass of feed water. When a brine seal is utilised, a large pocket of water remains stagnant around the RO membrane. Since the water is not chlorinated in the case of PA membrane elements, stagnant water is... 

Air dry in a rack loosely wrapped in foil for 60niin minimum. The slides may be left overnight to dry. 

Another type of reaction control realized by isotonic contraction of a PMAA membrane is shown in Fig. 27 In this case the invertase solution was placed in a glass tube, the lower part of which was loosely wrapped with the PMAA membrane. The contraction of the membrane, bringing about the shrinkage of the pore radius (isotonic contraction cf. Fig. 20 a) interferes with the permeation of the substrate molecules from outside. Fig. 27 shows the effects of pH change and addition of PEG on the rate of hydrolysis. It is seen that the addition of a small amount of PEG impedes the hydrolysis completely, whereas a pH change has no effect on the rate. PEG molecules adsorbed on the PMAA membrane can be removed by rinsing with a dilute NaOH... 

FIGURE 41.17 Artist s concept of thermally insulated electric-vehicle battery module with cutaway showing biploar Li-Al/FeS stack, lightweight loosely wrapped multifoil insulation, and thermally activated getter system for controlling heat transfer from module. (Courtesy of Argonne National Laboratory.)... 

Alternatively, measure the wet bulb temperature as follows Take a small piece of fabric and loosely wrap the bulb of a thermometer, leaving a short tail of the fabric dangling below the thermometer. Dip the tail of fabric into water so that the water soaks all the way up the fabric that is covering the thermometer bulb. Now measure the ambient air temperature using the thermometer with the fabric wrapped around its bulb. This is known as the wet bulb temperature. It will be lower than the dry bulb or ambient air temperature because the water vaporizing off the fabric cools the bulb of the thermometer. 

Thread the needle and make sure that the short end is about 3 to 4 inches long. This end will remain unknotted. Holding the other end of the thread between your thumb and forefinger, loosely wrap the short end around your forefinger two or three times while keeping the thread in place with your thumb. 

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