Experimental film

The other method is the ASTM cup method (34). In this method a desiccant is placed in a waterproof dish. The dish is covered with the experimental film and placed in an environmental chamber. The temperature and humidity ate set for the conditions of interest, typically 37.8 °C and 90% th. At regular intervals, the dish is removed and weighed. After a few days enough data have been gathered to describe a steady-state rate of weight gain, and the WVTR can be calculated. Typical experiments take about a week to complete. 

Experimental. Films were cast from Manjikian s standard casting solution( acetane formamide 30wt, cellulose acetate... 

One approach to a solution of this problem was put forward by Hansen (14), who derived general equations which express the overall experimental film absorbance in terms of the external reflectance of the substrate. These relations contain within them expressions for the individual anisotropic extinction coefficients in each geometric orientation. Solution of these general equations for the anisotropic extinction coefficients allows for an unambiguous description of the dipole orientation distribution when combined with a defined orientation model. 

Experimental films were prepared from polyamic acid or polyamide-imide solutions in 1-methyl-2-pyrrolidone (NMP) solvent by casting on soda-lime glass plates and curing in a forced air oven for one hour each at 80°C, 200°C, and 300°C. The resulting films were 25-50 microns thick. 

Experimental. Films of B-staged BCB were coated on salt substrates by spray deposition and cured in air at 250°C for one hour. This cure period was determined from the minimum time necessary for the elimination of the reaction exotherm as measured by DSC. After the cure cycle the films were removed by dissolving the substrate in a water bath. The freely standing films so obtained were between 25 mm and 50 mm thick. 

Although our main focus is on the short narrative film, we intend to demonstrate the ways in which each short form has borrowed freely from the others. It is important that less-experienced screenwriters realize that, even when the scripting of a narrative, documentary, or experimental film proceeds in an informal way—using improvisation, for example—the film itself still needs a purpose and shape to make a coherent whole. This is true even of stories that may concern themselves primarily with form, or form as context, as is frequently the case with postmodern films or videos. 

While it is true that there are filmmakers in the experimental and documentary area who continue to work in the short form, more and more filmmakers in these areas are moving to the long form as well (Bruce Elder or Su Friedrich in the experimental film genre, and the work of Ross McKelwee and Barbara Kopple in the documentary, for example). The short, at least in North America, is more and more an economic necessity for the student filmmaker and the novice professional, and while there are still short films produced in the educational corporate sectors, they are far fewer than in the past. 

Experimental narrative should not be confused with the more specifically nonnarrative experimental film or video. The experimental film or video is often entirely taken up with an issue of style. In the extreme (in more than one Norman McLaren film, for example), the film can concern itself with the variations of movements of abstract lines or shapes. In McLaren s films, line or shape give a visual dimension to an abstract musical piece. The narrative intention is at best remote more often in such work, it is not even a factor. In the experimental narrative, in contrast, narrative intention does have a role. However, the form or the style of the piece is as important as—in some cases more important than—the narrative. 

The parallels between the short film and the experimental film and video are even more striking. As in the case of the documentary, the experimental film or video offers cost advantages over the dramatic narrative. In addition, the history of experimental film and video has been marked by a willingness to take creative risks—a quality that affiliates these forms with innovation. The experimental film and video forms are, as a result, as much a center for invention as the documentary. 

Because experimental film and video put a greater emphasis on form or style than content, one can frame the genre as using style and content in a dialectical fashion or simply to see the form obsessed solely with style. The consequences are as follows ... 

Although the experimental film and video embrace style as the central quality of the genre, the short film varies in the degree of that embrace. Although it is true that style is very important in the short film, it needn t be the exclusive defining characteristic that it is in the experimental genres. Style will be less important should the filmmaker opt for a melodrama, but it will become more important if the filmmaker opts for a fable or a docud-rama or indeed an experimental narrative. 

Nevertheless, the parallels between the experimental film and video and the short film remain striking. 

Instrument. The analytical instrument for these experiments is shown schematically in Figure 1. This instrument was designed and built at The Dow Chemical Company for measuring the permeation of flavor and aroma compounds through polymer films. The gas handling section of the instrument contains the plumbing, containers of aroma solutions, and the experimental film. This enclosure is insulated, and the temperature can be controlled, + l C, from subambient to about 150 C. The detector is a Hewlett-Packard 5970 mass spectrometer. More details are available (2). 

Then a permeation experiment was completed by preparing a dilute solution of the permeant in nitrogen in the three liter flask and routing this gaseous solution past the purged, experimental film. 

The value of // is determined by going vertically from the value of Hy at point P up to the equilibrium line to give // at point R, as shown in Fig. 10.5-3. In many cases the experimental film coefficients k a and h a are not available. The few experimental data available indicate that hi a is quite large and the slope of the lines -h[ at kGoMsP) in Eq. (10.5-14) would be very large and the value of Hy would approach that of H y in Fig. 10.5-3. 

These workers stress that high temperatures encountered for limited periods in practice, (e.g. during pasteurisation, sterilisation or preparation of foodstuffs in plastics packs) must be simulated by use of appropriate test temperatures and times. Moreoever, experimental films made only for test purposes should be of the same thicknesses as the article that will actually be used, since the thickness of the film has a definite influence on the amount of additive migrating. The extent of migration also depends on the physico-chemical properties of the test material, including its density, surface quality and crystallinity. Test specimens, both of films and plastics containers should therefore be made under standard production conditions. 

The paper compares the numerical results obtained using a differential deflection point contact transient analysis with the detailed published experimental film thickness measurements presented by Glovnea and Spikes. Differences in the calculated and experimental behaviour are observed, particularly at the highest acceleration rates. An explanatory factor to account for the differences is proposed. 

Reply bv the Authors The cases analysed are in simple sliding as is made clear in the paper, and consequently inlet shear heating will be a factor in determining the initial steady state film thickness. It would be entirely realistic to include a thermal analysis as suggested. This would make the temperature adjustment a calculated value rather than a constant value adjusted to obtain the experimental film thickness. The work reported in... 

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