Vapor boxes applicability

PP films are commercially available with different coatings (acrylic and PVEXT) to improve heat sealing, hanier, and optical characteristics, as well as to lower the coefficient of friction. Also, metallized PP films are available to provide extremely low values of permeability to gases and vapor." PP films are well suited for bag-in-box applications in cereals, crackers, soup mixes, and stand-up pouches. PP is also an excellent material to fabricate injection-molded closures for HDPE, PET, and glass bottles. 

To avoid the loss of vapor-saturated air when applying the sample, a slot in the top of the box should allow the application of the sample without disturbing the atmosphere inside (VI). Only a few designs are satisfactory with respect to this very important point. 

The process is designed as an inexpensive mass-production application of vapor-phase deacidification, and it would be inappropriate to apply it indiscriminately without pretesting items where book components other than the paper were considered to be of artistic or historical value. Packs of loose sheets enclosed in archival storage boxes have also been processed, and all the material in the boxes and the boxes themselves were completely deacidified. In cases where an item to be processed is out of the ordinary, one can either draw on past experience or make a processing test on similar material of no value. 

Because of the need to remove water, most applications for aqueous adhesives are with materials that would allow transmission of water vapor. Hence the major uses are with paper, wood and fabric, either as binders or laminating adhesives. Typical applications of emulsion adhesives include the following remoistenable gummed tape, tube winding, box manufacture, plywood manufacture, woodworking, bookbinding, abrasives manufacture, and as textile adhesives. 

Raoult s law predicts that when we increase the mole fraction of nonvolatile solute particles in a solution, the vapor pressure over the solution will be reduced. In fact, the reduction in vapor pressure depends on the total concentration of solute particles, regardless of whether they are molecules or ions. Remember that vapor-pressure lowering is a colligative property, so it depends on the concentration of solute particles and not on their kind. In our applications of Raoult s law, however, we will limit ourselves to solutes that are not only nonvolatile but nonelectrolytes as well. We consider the effects of volatile substances on vapor pressure in the "Closer Look" box in this section, and we will consider the effects of electrolytes in our discussions of freezing points and boiling points. 

Figure 1 Schematic of the simulation box of a water-organic liquid system in closed (a) and open (b) geometries. Note that the open geometry contains additionally two liquid-vapor interfaces. The boundaries of the simulation cell are in solid, heavy lines and replicas of the cell due to the application of periodic boundary conditions are in dashed lines...

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