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Experiencing film

After experiencing films with characters who go through change and identifying with those characters, are we ourselves actually changed For instance ... [Pg.304]

Supported aqueous phase (SAP) catalysts (16) employ an aqueous film of TPPTS or similar ligand, deposited on a soHd support, eg, controlled pore glass. Whereas these supported catalysts overcome some of the principal limitations experienced using heterogeneous catalysts, including rhodium leaching and rapid catalyst deactivation, SAP catalysts have not found commercial appHcation as of this writing. [Pg.469]

Phototypesetting represented an easier way to compose type. Eady phototypesetters used an optical process, whereby a disk of characters, ia different sizes and typefaces, was spun under computer control. Each character was projected ia turn onto photosensitive film or paper. This was followed by systems where characters drawn on a cathode ray tube (CRT) exposed the photosensitive material. In each case, the operator iateracted with the system at a video screen that only showed the characters of the text (the iaformation content) and codes that iadicated how the characters were to look on paper. An experienced operator was required to obtain high quaUty results. [Pg.36]

In general, the requirements of heat resistance limit film thickness and therefore corrosion resistance. This is a particular problem when surfaces fluctuate between hot and cold. Coatings should be selected carefully, depending on the exact maximum temperature that will be experienced. Wherever possible, conventional materials should be used. The majority of air-oxidation coatings will be satisfactory up to 95°C and epoxies up to 175°C continuous dry heat. [Pg.131]

In addition to impurities, other factors such as fluid flow and heat transfer often exert an important influence in practice. Fluid flow accentuates the effects of impurities by increasing their rate of transport to the corroding surface and may in some cases hinder the formation of (or even remove) protective films, e.g. nickel in HF. In conditions of heat transfer the rate of corrosion is more likely to be governed by the effective temperature of the metal surface than by that of the solution. When the metal is hotter than the acidic solution corrosion is likely to be greater than that experienced by a similar combination under isothermal conditions. The increase in corrosion that may arise through the heat transfer effect can be particularly serious with any metal or alloy that owes its corrosion resistance to passivity, since it appears that passivity breaks down rather suddenly above a critical temperature, which, however, in turn depends on the composition and concentration of the acid. If the breakdown of passivity is only partial, pitting may develop or corrosion may become localised at hot spots if, however, passivity fails completely, more or less uniform corrosion is likely to occur. [Pg.790]

The reproducibility of the electrodeposition of conducting polymer films has been a very difficult issue. It has long been realized that each laboratory produces a different material and that results from different laboratories are not directly comparable.82 We have experienced reproducibility problems with almost all of the electrochemically polymerized materials used in our work. [Pg.558]

At the thin film limit, the hydrodynamic pressure will approach a distribution that is consistent with the pressure between the two solid surfaces in dry static contact, while the shear stress experienced by the fluid film will reach a limiting value that is equal to the shear strength of a boundary film. [Pg.82]

We infer the importance of the FeO c/Au interface which occurs for films as well as nanoparticles. However, since we observe FeO c/Au nanoparticles/Si02/Si(l 0 0) to be the most active of all samples we advance the hypothesis of the occurrence of a strong electronic effect at the FeOJ nanoparticle interface coupling through the FeO layer thus producing the high catalytic activity. Au promotion was also experienced in the catalytic activity of Ti02 overlayers [207]. [Pg.102]

Abstract In the last decade, the sonoelectrochemical synthesis of inorganic materials has experienced an important development motivated by the emerging interest in the nanostructures production. However, other traditional sonoelectrochemical synthesis such as gas production, metal deposits and metallic oxide films have also been improved with the simultaneous application of both electric and ultrasound fields. In this chapter, a summary of the fundamental basis, experimental set-up and different applications found in literature are reported, giving the reader a general approach to this branch of Applied Sonoelectrochemistry. [Pg.107]

Polymer Matrix Effects. In order to approximate the environment experienced by the arylcarbamate moieties in coatings based on aromatic diisocyanates, we chose to study the photochemistry of alkyl N-arylcarbamates in polymethacrylate (PMMA) and polypropyl-methacrylate (PPMA) films. First, however, 2a and 3a were irradiated in ethyl propionate (a model solvent for PMMA and PPMA) to determine the effect of the solvent polarity (dielectric) on the photolysis of the carbamates. Upon excitation at 280 nm, where the solvent absorbance was negligible, is 0.006 for 2a and 0j) is 0.005 for 3a. These values are significantly smaller... [Pg.124]

Two other features are notable in Table III. The swelling values for the compression molded samples (CM) run consistently less than those for the solvent-cast films. Apparently there is more "entrapment" of the amorphous portions within the crystallites during and after the molding. Secondly, the degradation experienced by the polymer hydrogenated at 69°C. (see Table II) instead of 52°C. is clearly demonstrated by the higher swelling value. [Pg.116]

One key experimental observation regarding the ZP films is that the films found on the tops of asperities are stiffer and exhibit chemical spectra indicative of longer phosphate chain lengths than films found in the valleys between asperities. These observations that differences in the conditions at the two distinct locations alter the elastic and chemical properties of the films. One of the key differences between the tops of asperities and the valleys is the pressure experienced by the zinc phosphates. Since the highest pressures, and greatest potential for wear, are achieved at the tops of the asperities, determining the response of ZPs to these pressures may aid in developing a clear picture of how the anti-wear films work. [Pg.118]


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See also in sourсe #XX -- [ Pg.97 ]




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