Evaluating films

Table I describes the resins that were evaluated. Films of the resins were applied to topographic substrates by spin coating from concentrated solutions of the resins in volatile spinning solvents using a Headway Research Model EC101 spin coater. After 2 minutes of spinning the coated substrates were transferred to a hot plate for baking. The temperature of the hotplate was measured with a surface thermometer.

Transportation processes upstream of succinic acid and 1,4-butanediol are disregarded, except for sea transport of crude oil. Treatment of wastewater generated in the plant and preparation of catalysts used in production are deemed negligible factors and omitted from this evaluation. Based on data provided from the plant of Showa Denko, auxiliary materials used in production other than succinic acid and 1,4-butanediol account for a mere 0.2% of raw materials by total weight. They are omitted from this evaluation. Additionally, we do not evaluate film processing in this study, since the process is nearly identical for all products. 

For lithographic evaluation, films of P(MM-AMS) were cast from solutions in 2-ethoxyethanol and prebaked one hour at 150°C. Under these prebake conditions, the ester was converted largely back to the anhydride as... 

Lithographic Evaluation. Films were spin-coated onto silicon substrates from 10% solutions in chlorobenzene and prebaked at temperatures between 90 °C and 100°C for 1 hour to ensure solvent removal. The thickness of each film was about 5000 A. Electron beam exposures were performed on the AT T Bell Laboratories electron beam exposure system (EBES-I) operating at 20 kV with a beam adress and spot size both equal to 0.25 . A minimal cure time was required since there is no post-exposure reaction (4,16). 

Lithographic Evaluation. Films of PVTMSK were spin coated on polished silicon wafers by using 5 or 10% solutions in chlorobenzene. The lithographic sen-... 

S.C. Pater, L.A. Felton, Techniques to assess film coatings and evaluate film-coated products. Drug Dev Ind Pharm 36 (2) (2010) 128-142. 

ANSI (1996) Method for evaluation films for monitoring x-rays and ganna rays having energies up to 3 million electron vpolts. ANSI/NAPM standard no. IT2.10-1996, American National Standards Institute, New York... 

The same result has been found by Lagone et al, (1995) who used poly[(ethyl-alanate)-co-(imidazole)phosphazene] derivatives for in umo evaluation. Films of this polymer type were subcutaneously implanted in rats. The animals were killed after 30 days, or 60 days. Biopsy samples of the implant zone were histologically examined. In both cases the animals were healthy. The biological material surrounding the polymer was found to correspond to fibroblast collagen with only a few monocytes in the internal site. 

Evaluate films made from agricultural products with built-in chromophores that absorb light for their ability to protect potatoes against greening, browning, and spoiling (73). 

It is apparent from Eqs. (29) that the R/R spectra of a surface film on an absorbing substrate do not always allow for a straightforward interpretation of the film optical constants. The spectra are by no means transmission-like but are markedly influenced by the optical properties of the substrate. Therefore, it appears to be desirable to evaluate directly the film dielectric function, 2 = 2 f 2, from the experimentally determined quantity R/R rather than attempting a detailed interpretation of the AR/R spectra alone. In the following, we briefly discuss three different methods for evaluating film optical constants. 

Radiographic inspection is performed to reach a decision about the acceptability of the component or product being tested. Before any evaluation can be made, the interpreter must be certain that the images are satisfactory. In addition, the interpreter must have a solid understanding of the following in order to be successful with the interpretation of the radiographic film for welding quality. 

Notea A., Applications of Film Tomography Technique for QNDE , Review of Progress in Quantitative Nondestructive Evaluation, vol. 6A, 1987, pp. 433-440. 

To evaluate the image quality of the processing system, one can determine classical parameters like spatial resolution, contrast resolution, dynamic range, local and global distortion. Guidelines for film digitization procedures have been well described now. Furthermore, a physical standard film for both equipment assessment and digitization calibration and control, will be available in a next future (4). 

The corrosion inspection and wall thickness measurement of pipes was performed in the classical way both on film and on the monitor using simple software measuring tools. Additionally algorithms were developed for an interactive, computer supported evaluation. 

After this calibration step (the effective absorption coefficient is determined from a known wall thickness change and the corresponding variation of the optical film density) the evaluation of local wall thickness changes Aw (corresponding to De,o) from the nominal wall thickness w o , (corresponding to Dnom) can be done according to ... 

For the practical evaluation of the algorithm described previously it is integrated into the NDT Sean Manager system (DBA Systems Inc, Melbourne, FL, U.S.A). This system allows film digitisation, display, evaluation and archiveraent of images /3,4/ and was developed for the needs of computer based industrial NDT film inspection. A snapshot of the user interfaee for wall thickness evaluation is shown in fig. 3. 

Now days the devices operating in the radiowave range are designed and they used for oil film thickness measurements and for the oil spills volume evaluation. The device operating on the frequencies from 37,5 to 10,7 begHz provides the measurements of the film thickness in the range from 100 to 6 — 7 pm. It means that all accident happening on the seas surface may be estimated. 

Equations X-12 and X-13 thus provide a thermodynamic evaluation of the change in interfacial free energy accompanying adsorption. As discussed further in Section X-5C, typical values of v for adsorbed films on solids range up to 100 ergs/cm. ... 

It was shown in Section X-3B that a formal calculation can be made of the film pressure, or reduction in the surface free energy of the solid, by evaluating... 

A more elaborate theoretical approach develops the concept of surface molecular orbitals and proceeds to evaluate various overlap integrals [119]. Calculations for hydrogen on Pt( 111) planes were consistent with flash desorption and LEED data. In general, the greatly increased availability of LEED structures for chemisorbed films has allowed correspondingly detailed theoretical interpretations, as, for example, of the commonly observed (C2 x 2) structure [120] (note also Ref. 121). 

To simplify FECO evaluation, it is conmion practice to experimentally filter out one of the components by the use of a linear polarizer after the interferometer. Mica bireftingence can, however, be useftil to study thin films of birefringent molecules [49] between the surfaces. Rabinowitz [53] has presented an eigenvalue analysis of birefringence in the multiple beam interferometer. 

An interesting example of a large specific surface which is wholly external in nature is provided by a dispersed aerosol composed of fine particles free of cracks and fissures. As soon as the aerosol settles out, of course, its particles come into contact with one another and form aggregates but if the particles are spherical, more particularly if the material is hard, the particle-to-particle contacts will be very small in area the interparticulate junctions will then be so weak that many of them will become broken apart during mechanical handling, or be prized open by the film of adsorbate during an adsorption experiment. In favourable cases the flocculated specimen may have so open a structure that it behaves, as far as its adsorptive properties are concerned, as a completely non-porous material. Solids of this kind are of importance because of their relevance to standard adsorption isotherms (cf. Section 2.12) which play a fundamental role in procedures for the evaluation of specific surface area and pore size distribution by adsorption methods. 

At the junction of the adsorbed film and the liquid meniscus the chemical potential of the adsorbate must be the resultant of the joint action of the wall and the curvature of the meniscus. As Derjaguin pointed out, the conventional treatment involves the tacit assumption that the curvature falls jumpwise from 2/r to zero at the junction, whereas the change must actually be a continuous one. Derjaguin put forward a corrected Kelvin equation to take this state of affairs into account but it contains a term which is difficult to evaluate numerically, and has aroused little practical interest. 

In the pioneer work of Foster the correction due to film thinning had to be neglected, but with the coming of the BET and related methods for the evaluation of specific surface, it became possible to estimate the thickness of the adsorbed film on the walls. A number of procedures have been devised for the calculation of pore size distribution, in which the adsorption contribution is allowed for. All of them are necessarily somewhat tedious and require close attention to detail, and at some stage or another involve the assumption of a pore model. The model-less method of Brunauer and his colleagues represents an attempt to postpone the introduction of a model to a late stage in the calculations. 

GNETICMATERIALS - THIN FILMS AND PARTICLES] (Vol 15) -imaging techniques [NONDESTRUCTIVE EVALUATION] (Vol 17) -useinNDE [NONDESTRUCTIVE EVALUATION] (Vol 17)... 

An interesting material with both electro- and therm ochromism behavior, Li VO2 was evaluated for a "smart window" appHcation (25). Films of Li V02 were prepared by reactive sputtering and annealing an electrolyte of LiClO and propylene carbonate. 

Other Models for Mass Transfer. In contrast to the film theory, other approaches assume that transfer of material does not occur by steady-state diffusion. Rather there are large fluid motions which constantiy bring fresh masses of bulk material into direct contact with the interface. According to the penetration theory (33), diffusion proceeds from the interface into the particular element of fluid in contact with the interface. This is an unsteady state, transient process where the rate decreases with time. After a while, the element is replaced by a fresh one brought to the interface by the relative movements of gas and Uquid, and the process is repeated. In order to evaluate a constant average contact time T for the individual fluid elements is assumed (33). This leads to relations such as... 

---