Transmission study experimental design

A Box-Behnken experimental design was conducted on an 80 inch wide commercial vacuum metallizer at a constant line speed using Evaporation chamber pressure, chill roll temperature and final film optical density as the three independent process variables. Table 1 lists the variable range studied and table 2 lists the experimental runs in design order. The experiment consists of 12 treatment combinations with five center points to determine the error in the measurements. During the experiment the order of the treatment combinations was randomized and the random order used to minimize any systematic error in the testing.. The response variables were oxygen transmission rate, optical density transverse variability, metal pick off with Scotch 610 and Scotch 600 tapes. 

The structural anisotropy in crystalline or structurally ordered BPDA-PFMB films was studied in this laboratory with wide-angle X-ray diffraction (WAXD) methods. In brief, WAXD experiments were designed to examine both the reflection and transmission modes of thin-fihn samples. In addition, uniaxially oriented polyimide fiber WAXD patterns were obtained to aid in the identification of the film structure. The film WAXD pattern obtained from the reflection mode corresponded well to the fiber pattern scanned along the equatorial direction (Figure 16.3), " which indicates that the reflection mode pattern represents the (hkQ) diffractions. On the other hand, as shown in Figure 16.4, the (001) diffractions were predominant in the film WAXD pattern obtained via the transmission mode. This pattern corresponded to the fiber pattern scanned along the meridian direction. These experimental observations clearly indicate that the c-axes of the crystals are preferentially oriented parallel to the film surface however, within the film, they are randomly oriented. 4.2 5 j( should be pointed out that the WAXD experiments are only sensitive to crystalline or ordered structures in polyimide films. They do not provide any information on the amorphous regions. 

Hence, in contrast to transmission spectroscopy, where the sample intercepts the path of the IR beam, in ATR the sample is placed on an IR-transparent crystal (IRE, internal reflection element), permitting total internal reflection. In vivo (or in situ) experimentation is permitted by virtue of one of several design arrangements (a) the region of skin under study may be placed directly in contact with the crystal (b) a remote fiber-optic probe (with IRE head) may be used to transfer the IR beam from the source to the sample and ultimately to the detector and (c) samples removed from the subject may be placed directly onto the crystal. 

The first applications were based purely on experience from previous smaller projects. Since recently, more well-documented design criteria are available. Stability criteria for these units were determined based on analytical and experimental studies. For high energetic wave sites the units can be hydraulically anchored with cables to the sea bed. Wave transmission was studied in Canada. Technical design aspects are treated by Harris. ... 

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