Shape of the package

Not only can absorption alter the aroma and flavor of a product, it can also change the mechanical properties of the polymer. Swelling and gas permeability are factors that effect the physical properties of a polymer (Robertson, 2006 Sadler and Braddock, 1991 Safa and Bourelle, 1999). Swelling occurs when compounds are absorbed into the polymer and distort the shape of the package. As absorption increases there is also a subsequent increase in gas permeability. This increase in gas permeability can affect the shelf-life and sensory quality of a food by, for example, increasing oxidation. In very severe cases, absorption can affect package integrity. 

For a given level of S)meretic pressure, syneresis increases with increasing gel surface area to volume ratio. The shape of the package containing the gel may also influence syneresis for example, in a package with sloping... 

Stacking test Unless the shape of the packaging effectively prevents stacking, the specimen shall be subjected, for a period of 24 h, to a compressive load equal to the greater of the following ... 

However, an exact solution to the problem of convective diffusion to a solid surface requires first the solution of the hydrodynamic equations of motion of the fluid (the Navier-Stokes equations) for boundary conditions appropriate to the mainstream velocity of flow and the geometry of the system. This solution specifies the velocity of the flrrid at any point and at any time in both tube and yam assembly. It is then necessary to substitute the appropriate values for the local fluid velocities in the convective diffusion equation, which must be solved for boundary cortditiorts related to the shape of the package, the mainstream concentration of dye and the adsorptions at the solid surface. This is a very difficrrlt procedure even for steady flow through a package of simple shape. " ... 

Thermoforming. Thermoforming is the most common method of fabricating sheet into three-dimensional packaging. In conventional thermoforming, the sheet is heated to its softening point or just below the melting temperature. The softened plastic is forced by differential air pressure into an open-top mold to assume the shape of the female mold. The mold is chilled and the plastic sheet solidifies and is then removed from the mold. 

Materials problems. Components of the packaging material dissolving in the product, changing taste, odor, shape, texture, etc. 

Electrode boilers are manufactured as factory-ready and are therefore examples of packaged boilers. Smaller units are normally housed in square, sheet metal cabinets, but larger units are normally round pressure vessels with the insulation following the shape of the vessel. 

They are then forced through a narrow die to form a hollow tube called a parison. A chilled mold is then clamped around the parison and inflated from the inside by air. The air pressure presses the parison against the mold, and it hardens in the shape of the mold. The mold then opens and ejects the HDPE bottle. The bottle is then trimmed and conveyed to the milk filling station. The waste plastic is ground for reuse. GHG emissions associated with the embodied energy of the packaging machinery may be calculated but typically fall near the 1% cutoff line and can be excluded (Cashman et ah, 2009). 

Shrink wrap is a film that is applied loosely around products, then sealed and shrunk by heating to take the shape of the contained products. It can be used to bind multiple packages, or to secure an entire pallet of packages, to bundle magazines and papers, to protect and display albums, CDs and so on. It is usually made of LLDPE, LDPE or polypropylene. 

The calculations above allowed the positions of atoms to change within a supercell while holding the size and shape of the supercell constant. But in the calculations we introduced in Chapter 2, we varied the size of the supercell to determine the lattice constant of several bulk solids. Hopefully you can see that the numerical optimization methods that allow us to optimize atomic positions can also be extended to optimize the size of a supercell. We will not delve into the details of these calculations—you should read the documentation of the DFT package you are using to find out how to use your package to do these types of calculations accurately. Instead, we will give an example. In Chapter 2 we attempted to find the lattice constant of Cu in the hep crystal structure by doing individual calculations for many different values of the lattice parameters a and c (you should look back at Fig. 2.4). A much easier way to tackle this task is to create an initial supercell of hep Cu with plausible values of a and c and to optimize the supercell volume and shape to minimize... 

Identification by product name, product code (if available), name and address of the manufacturer, and a physical description of the packaging component (e.g., type, size, shape, and color)... 

Orientation Once the particles are dispersed in the polymer, they must be oriented so that the flat surface of the clay is parallel to the surface of the packaging material to maximize the barrier effect. Several models have been developed in order to describe the mass transfer within the nanocomposites. Most models assume that the platelets have a regular and uniform shape (rectangular, sanidic, or circular) and form a regular array in space. They are either parallel to each other or have a distribution of orientations, with the... 

Tovex C is designed for chute blasting or secondary blasting. It is packed in a moldable package and conforms well to the shape of the rock to be blasted... 

A large variety of continuum models have been proposed and many are available in popular quantum chemical modeling packages. They differ in the sophistication of the procedure used to determine the shape of the cavity. In the simplest case, this is just a sphere, but most models nowadays use more tailored cavities (as in Figure 10.3), generated, for example, from the combination of a set of spheres placed around individual solute atoms. In most cases, the models include a relaxation of the electronic structure in response to the electric held created by the solvent around it, and in most cases this is then treated fully self-consistently. This effect can be quite important in some cases, as a polar solute may become considerably more polar due to interactions with a polar solvent. Different models are also parameterized in different ways. 

If a figrrre has been computer generated, many of the above concerrts may have been resolved automatically by the software plotting package. The user shotrld, however, be aware that the default plot scales are often not ideal. Most plot programs allow the user to control the aspect ratio, the scale ranges, and the shape of the symbols. You must also make sure that the plotted variables are correctly specified and their units clearly indicated. 

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