Film systems classification

A New US Film System Classification and Image Quality Assessment. 

As a first step in the direction outlined here some manufacturers and BAM last year discussed the problems and the possible procedures of such a system of quality assurance. As a result of this meeting round robin tests for the harmonization of the measurements of film system parameters and a possible procedure of surveillance of the quality of film systems were proposed. Closely related to these the BAM offers to perform the classification of film systems. But as during the production of films variations of the properties of the different batches cannot be avoided, the results of measurements of films of a single batch will be restricted to this charge, while only the measurements and mean of several batches of a film type will give representative values of its properties. This fact is taken into account already in section 4 of the standard EN 584-1 which can be interpreted as a kind of continuous surveillance. In accordance with this standard a film system caimot be certified on the base of measurements of a single emulsion only. 

In case of mixed systems the procedure must be varied and it would be restricted to the special film systems of interest, of course. Mixed systems would be used by inspection companies and industrial users who normally do not dispose of the equipment for measurements as mentioned above. In these cases instead of a round robin test only periodical measurements of the properties of these mixed film systems by an independent third party institution can be used for film classification and continuous surveillance. 

Electrode Film Systems. Formation, General Properties, Classification... 

Classification of Film Systems. Processes in Chemical Film Systems... 

The qualitative classification of film systems, both chemical and electrochemical, was proposed in [25]. It is based on the prevailing type and magnitude of conductivity of the film considering the film as a PFC as mentioned above. It is as follows ... 

One can see that the classification scheme (1.11) points out the separate group of chemical film systems where the process does not involve electric current across the interface. Let us briefiy overlook the main features of such systems. 

This chapter analyses some experimental examples, demonstrating qualitatively the concept of electrode film system (EPS). The discussion is based on the classification of EPS considered in Chap. 1. 

According to the developed classification (see Chap. 1), this film system belongs to the category of the ion-semiconductor ones with very low total conductivity— that is, to dielectric type of systems. Its low conductivity constitutes of electronic (semiconductive) and ionic (migrative) parts. The electronic band theory prescribes the exponential temperature dependence of the electronic conductivity. Then, the electronic current can be written as... 

The classification of electrode film systems is proposed based on the above ideas, and main qualitative regularities of the electrolytic processes in the film systems of different kind are envisaged in Chap. 4. In particular, the mechanism of formation of cathode deposits is considered. It is shown that the deposition of metal-salt carrots or compact metal layers depends on the properties of the cathode film system (prevailing type and ratio of the electronic and ionic conductivity of the film). The nature of crisis phenomena at the electrodes is also analysed (anode effect in fluoride melts, complications at the electrolytic production of Al-Si alloys in industrial-scale electrolytic cells), the mechanisms are elaborated and the means to escape the crises situations are developed. 

EN 584-1, Non-destructive testing—Industrial radiographic film—Part 1 Classification of film systems for industrial radit aphy, Comite European de Normalisation, 1994. 

The combination of contrast and granularity produces a signal to noise ratio which allows for direct comparison of various films. The classes have minimum values for eontrast and maximum values for graininess. The ASTM classification system employs the same parameters as the European Standard EN584-1 and ISO CD (see Table 1). 

Note that the original definition has now evolved into a dichotomous classification Truly chiral systems exist in two distinct enantiomorphous states that are interconverted by space inversion but not by time reversal combined with any proper spatial rotation, whereas falsely chiral systems exist in two distinct enantiomorphous states that are interconverted by space inversion or by time reversal combined with any proper spatial rotation.34- 35 The process of time reversal, represented by the operator T, is the same operation as letting a movie film run backward. The act of inversion [i.e., time reversal] is not a physical act, but the study of the opposite chronological order of the same items. 38... 

The first two types of interaction are certainly physical adsorption the fourth is certainly chemisorption the third, which is a postulated mechanism whose actual occurrence has not yet been adequately demonstrated, exists in a twilight zone that defies classification as either physical or chemical adsorption. Previous papers of this series have not been concerned with the source of the adsorptive potential, but have postulated only that the adsorbed film be mobile their considerations could apply, therefore, to all adsorption situations other than No. 4. The present paper is devoted to a consideration of the adsorptive potential arising from 1 and 2—that is, physical adsorption properly so called. This general topic has been discussed by de Boer (5) for a number of specific cases the theory and techniques that we have developed enable us to derive from experimental data a quantity, Pads, the depth of the adsorptive potential well, which can also be calculated a priori from physical properties of the system. We are therefore able to compare theory and observation and so have an independent test of conclusions reached in previous papers. 

Note "Photographic or Cinematographic Goods" refers to HS (Harmonized Commodity Description and Coding System) Code 37. Products in this classification include "photo plates and film, flat, sensitized, unexposed photo film in rolls sensitized, unexposed photo paper, paperboard and textiles, sens, unexposed photo plates, film, paper, etc, exposed, not developed photo plates and still film, exposed developed motion-picture film, exposed and developed photographic chemicals, unmixed products retail packed."... 

Many modern dermatological formulations are washable oil-in-water systems. Simple aqueous lotions are also used as they have a cooling effect on the skin. Ointments are used for the application of insoluble or oil-soluble medicaments and leave a greasy film on the skin, inhibiting loss of moisture and encouraging the hydration of the keratin layer. Aqueous creams combine the characteristics of the lotions and ointments. A classification of semisolid bases is given in Fig. 9.24. 

From the above it is evident that metal surfaces may be utilized as templates if certain conditions are met. If we consider reconstructed surfaces the reconstruction has to be stable during further deposition of material. The same holds for nanopatterns formed by deposition of thin films. Likewise vicinal surfaces may facet during the deposition of further material. This section will therefore be dedicated to the use of metal surfaces as growth templates. We use the classification of the systems that was estabhshed in Sect. 2 and begin with reconstructed metal surfaces. 

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