The principal problems concerning the theory and practice of the acutance measurements of photographic images are considered. The principal correlations are presented and the influence oi the optical density and gradient of the characteristic curve on the acutance is discussed. The method of sample preparation is described and the conditions of border curve measurement are presented.
The title compounds 1 are synthesized starting from the 5-amino-3-methyl-1H-pyrazole 3 in a four step synthesis. By reaction of 3 with phenylsulfenyl bromide to the 4-phenylthio-pyrazole 4, nitrosation to the diazonium salt and reduction to the hydrazine 5, followed by acylation with 4-(4-nitrophenyl)-butyric acid chloride and cyclization of the resulting hydrazide 6 the pyrazolo triazole 7 was obtained. The reduction of the nitro group in 7 led to the substituted aniline 8. The coupler molecule 8 was modified by acylation with technically interesting ballast acid chlorides. By oxidation the phenylmercapto leaving group was converted into a sulfoxide or a sulfone group. The growing acceptor strength of the leaving groups leads to higher acidity of the couplers - characterized by their acid constants-, while the coupling rate decreases. The coupling rate was determined by Bash photolysis of aryl azides. The purple azomethine dyes were prepared and characterized spectroscopically.
In the present paper the influence of some alkaline metal ions, earth alkaline metal ions and earth metal ions on the kinetics of the I-131-mass transfer is investigated in the system AgI-gelatine-I-131(-). From the dependence of the activation parameters of the I-131-mass transfer on the concentration of the Li+-, Mg+-, Ca2+- and Al3+-ions, respectively (as Cl- and NO3-, respectively), statements can be derived for the interaction of these ions with the gelatine in the temperature range of the unfolded and folded gelatine. In this case it could be shown that the Ca2+-ions in low concentrations cause an influence on the folding of the gelatine. Higher Ca2+-concentrations shift the beginning of the formation of the triple helix to lower temperatures. In the temperature range of the unfolded gelatine, Mg2+- and Ca2+-ions cause an association of the gelatine macromolecules which leads to a decrease of the velocity of the I-131-mass transfer. The addition of a larger amount of the lice in the presence of a higher concentration of Ca2+-ions leads to a splitting of the associated gelatine macromolecules. The binding of the Ca2+-ions with gelatine and, therefore, the velocity of the Ostwald ripening and the folding processes during the formation of the triple helices is determined mainly by the concentration of the carboxyl groups in the gelatine. A new method is presented which characterizes the supra-molecular interaction between proteins and inorganic and organic substrates, respectively. The advantages and the disadvantages of this method will be discussed in detail.
In the present paper a report is given about the influence of PdCl2 on the kinetics of the phase interface processes in the course of the Ostwald ripening of the AgBr and AgI crystals. The radiochemical measurements showed, that the velocity of the Br-82(-) and I-131(-) mass transfer respectively in the systems AgBr - PdCl2 - Br-82(-) and AgI - PdCl2 - I-131(-) respectively is decreased with increasing concentration of the PdCl2. It were obtained characteristic points, which are an indication on the change of the mechanism of the phase interface processes. In the presence of higher PdCl2-concentrations it comes to a blocking of the velocity of the mass transfer. The concentration of the PdCl2, which is necessary to the blocking is explained with the blocking of the active centres of the grow on the AgBr- and AgI-crystal surface and the binding of the interstitial lattice silver ions about this centres. From the radiochemical measurements to the kinetics of the Br-82(-)-mass transfer the concentrations of the photographically active substances are obtained which are necessary to the doting of the AgBr crystals. It is interesting to find out that the concentration of the photographically active substance which is present on the characteristic points has the same quantity how was found through other physically and photometrically methods.
In the present paper the kinetics of the mass transfer of the (110)mAg(+)-ions at silver halide crystals was investigated by means of radioactive tracers in dependence of the thermal pretreatment of the crystals. The rate of the (110)mAg(+) mass transfer processes at AgCl- and AgBr-crystals is strongly influenced by the temperature and the duration of thermal pretreatment. The mass transfer at AgBr is retarded linearly, with rising temperature of the pretreatment. However, the rate of mass transfer processes at AgCl decreases rapidly in the temperature range from 180 degrees C to 200 degrees C of the pretreatment. The rate of the mass transfer at the AgBr-layer decreases upon prolonged thermal pretreatment. The influence of the concentration of Ag+ ions in the solution (specific activity) on the rate of the mass transfer was investigated, too. It was found that the specific activity is influencing the rate of the mass transfer. This is due to the increasing solubility of AgBr and AgCl in solutions with higher Ag+ concentrations. The size of the specific surface of the silver halide crystals decreases during thermal pretreatment. Therefore, it is not possible to make any statements on the influence of the thermal pretreatment on the perfection of the crystals, in particular on the concentration of interstitial silver ions. The role of the (110)mAg(+)-mass transfer and the amount of the exchanged Ag+-ions are increasing in the order AgCl, AgBr and AgI.
The commonly used indicators of photographic image quality, (e.g. RMS, MTF, acutance integral quality factor and others) require a number of measurements, calculations and data transformations. Conventional methods of the evaluation of these factors are laborious and material consuming and are not sufficient for the present precision of measurements. These difficulties can be avoided by the use of a very expensive and specialized apparatus. In our case a suitable apparatus has been constructed and specialized computer programs have been developed for the simple evaluation of quality factors of the photographic image. The problems of the recording of the optical density fluctuation, measured by microdensitometric scanning are presented in this work, together with problems related to measurements of the edge spread function. Methods and algorithms of the data processing and the computation of functions and factors of photographic image quality are also presented and discussed.
The microstructure - average size and size dispersity - of the microcrystalites building up AgBr layers is investigated as a function of the deposition rates in the range of 40-950 Angstrom/s on linearly moving substrates and in the range of 20-60 Angstrom/s on static ones. Unexpected results suggesting an independence of the microcrystallite average size on these deposition rates are obtained. It is supposed that at high supersaturations a threshold value of the deposition rate exists, beyond which the average size remains practically unaffected. It is established that this threshold value amounts to 20 Angstrom/s upon deposition on static substrates and that it is below or equal to 40 Angstrom/s in the case of linearly moving ones. Following the theory, the results obtained at the same deposition rate are interpreted assuming that the influence of the kinetic parameters on the average size of the microcrystallites prevails on the thermodynamic ones under the specific conditions of nucleation and crystal growth.
The East chemical reduction of silver ions in aqueous solutions containing protective colloids leads to silver sols whose UV-visible absorption spectra display cluster bands at 300 nm [Ag-9(+),Ag-3],340 nm [Ag-5], 360 nm [Ag-7, big clusters consisting of any tens silver atoms] as well as colloid bands at 390 nm and 410 nm [plasmon absorption band of metallic silver particles with a diameter around 4 nm, complexated by Ag+ ions]. If the cluster growth is restrained (e.g. sodium polyacrylate, lowered temperature) only the 340 nm band exists for a short time and, if exposed to air, it disappears completely. If the cluster growth is accelerated (e.g. raised temperature) in addition to the 340 nm band a weak 410 nm absorption maximum and a broad absorption region peaking at 360 nm, occur. At admission of air at first the region peaking at 360 nm, and finally the 340 nm absorption band disappear. Simultaneously an absorption in the 420 nm to 570 nm range raises. In presence of gelatin only a stable plasmon absorption band at 390 nm occurs, shifting to 410 nm if exposed to air accopanied by raising of an absorption in the 420 nm to > 600 nm range. It is concluded, that Ag-7 clusters and/or bigger clusters with any tens silver atoms are the start point for a further growth to bigger metallic silver particles and-colloids.
UV disinfection of drinking water is accepted as state of the art. The hygienic safety of a WEDECO UV unit 3-LB-10 was tested in practical application for disinfection of drinking water. E.coli ATTC 23716 was suspended in drinking water and irradiated with varying UV transmission (21 to 70%, thickness 10 cm) and constant water flow (108 m(3)/h). Fluorescein was used as transmission reducing substance.
With the development of diazonium salts absorbing in the longwave region a possibility for research work on colored diazotype materials was opened up. We succeeded in deriving not only the known yellow diazonium salts of the monodiazoted 4-phenylendiamine type but also diazonium compounds which absorb green and red light. After discussion of a lot of problems of diazonium salts, questions of the image dyes and the structure of colored diazotype layers are dealt with.
The Kinetics of silver sulfide formation by transformation of thiosulfate within a pure silver chloride emulsion containing cubic crystals is studied by measurement of optical transmission and remission spectra. In addition to reaction parameters such as temperature, free silver ion concentration(pAg), hydrogen ion concentration (pH) and thiosulfate starring concentration the catalytic influence of silver sulfide on further thiosulfate decay is under investigation. An autocatalytic reaction mechanism for the formation of silver sulfide on AgCl cubic crystals is observed, it may be discussed in analogy to the growth of silver halide al (100) crystal faces. A mathematical model for the reaction is derived giving results that are in good correspondence with the experimental observations.
The processe concerning the formation of non-silver photographic images by complexing Cu(II)-ions with alpha-benzoinoxime has been investigated. The kinetic image formation curves D-soild (balck) (inverted) (triangle)=f(D-Ag) in dependence of reagent concentration of processing solution and of toning time have been presented. It has been shown that the non-silver image consists from copper(II) hydroxide Cu(OH)(2) and from Cu(II)-benzoinoxime complex having copper(II)ion/ligand ratio equal to 2:2. It has been noted that the presented process of formation of non-silver photographic image with above-mentioned carriers is suitable to amplification and toning in green colour.
In the present paper a report is given about radiochemical studies to the kinetics of the mass transfer on silver halide crystals in the presence of unfolded and folded gelatin. With the beginning of the building of the triple helix of the gelatin it comes to a change of the velocity of the mass transfer and of the respective activation parameters. The result shows, that the activation parameters for the folded gelatin are important lower than for the unfolded gelatin. The point of intersection of the respective Arrhenius-curves For the unfolded and the folded gelatin is the beginning of the folding of the gelatin. It was found for the gel point a temperature range from 30 to 40 degrees C. The presence of impurities, which can exercise with the gelatin about hydrogen-bonds supramolecular interactions, induces in dependence on the concentration of these substances a shift of the beginning of the triple helical building to lower temperatures. In the present paper it is investigated the influence of alkaline and acid processed bone- and hide gelatins on the kinetics of the I-131(-) -mass transfer and it are derived statements to the folding of the respective gelatin.
