Photographic Developer Research Articles

Exposition à la lumière de plaques cristallines de bromure d'argent, au cours de leur développement électrolytique

AbstractThin polycristalline sheets of pure or doped silver bromide have been developed indirectly at the contact of a platinum wire connecting the crystal with a photographic developer. During the development, the crystals have been exposed several times to an intense flash of white or monochromatic light.

Analytical Methods of the Photographic Developer D-85b for Graphic Arts Films

Analytical Methods of the Photographic Developer D-85b for Graphic Arts Films

Some Aspects of Developer and Fixing Bath Concentrates Based on Potassium and Ammonium Salts Respectively

The limited solubility of some potassium salts in comparison to corresponding sodium salts is known from analytical chemistry; the analytical behaviour of ammonium salts is similar to that of potassium salts.On the other hand, potash and potassium sulphite which are of interest for photographic developers ore several times as soluble as soda and sodium sulphite. Most developer concentrates, therefore, contain potassium salts. However, certain processing conditions may lead to turbidity or precipitation in the developers, due to the formation of sparingly soluble potassium hydroquinone disulphonate.Commercial fixing bath concentrates contain ammonium thiosulphate which is much more soluble than sodium thiosulphate. Potassium thiosulphate is only slightly more soluble than sodium thiosulphate and, moreover, proves useless as a fixing agent. Fixing baths on the basis of ammonium thiosulphate are superior to those based on the corresponding sodium compound in the processing of films containing silver iodide.In practical use the formation of crystalline deposits containing ammonium, silver, iodide and thiosulphate ions may occur.

Skin disease from photographic colour developers.

Skin disease from photographic colour developers.

Application of Gas Chromatography to the Analysis of Developing Agents in a Photographic Developer

Application of Gas Chromatography to the Analysis of Developing Agents in a Photographic Developer

Evaluation of Commercial Photographic Developers Which Intensify Silver Halide Spots on Paper Chromatograms.

Evaluation of Commercial Photographic Developers Which Intensify Silver Halide Spots on Paper Chromatograms.

Autoradiography with tritium.

In autoradiography, a photographic emulsion is placed in contact with a specimen containing radioactivity and stored in the dark. The radiation, passing through the emulsion, sensitizes silver bromide granules so that they can be reduced to metallic silver by a photographic developer. One then sees a pattern of silver grains lying above the specimen. (The technique [1] employed in the present studies made use of stripping film which was floated over a histological preparation. In some cases Feulgen staining was performed before autoradiography; in other cases the specimen was stained through the emulsion after photographic development.)

Identifizierung Organischer Verbindungen : LIV. Mitteilung. Papierchromatographische trennung und identifizierung fotografischer entwicklersubstanzen

A method has been developed for the separation and identification of 16 substances that are used as developing agents in various commercial photographic developers. These substances are separated by chromatography on paper impregranated with formamide using neutral or basic solvent systems, or on untreated paper using acid systems, or on paper impregnated with potassium chloride using a neutral solvent.

X-ray diffraction analysis of industrial dust.

Abstract Procedures used routinely in the laboratories of the Division of Occupational Health for the x-ray diffraction analysis of industrial dust are presented with particular reference to new techniques for the collection and analysis of air-borne dust when the total amount of sample is of the order of 1 milligram. The composition is given of a photographic developer for x-ray diffraction films which has low fogging properties and which provides a wide-range, linear intensity-density relationship. The use of beryl as an internal standard for the quantitative determination of quartz in industrial dust is discussed and results obtained by chemical methods are compared with results obtained by x-ray diffraction methods.

A New Photographic Developer for Astronomical Work.

view Abstract Citations References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A New Photographic Developer for Astronomical Work. Fernie, J. D. Abstract Experiments applying a new, commercially available developer, Acufine, to astronomical spectroscopic plates are described. Sensitometric measurements indicate that this developer effectively increases the emulsion speed by half a magnitude, compared to development in D-19, while simultaneously producing a finer grain. Contrast is moderate, and developing times are about 6 min at 700 F. When used with its replenisher, Acufine appears to be stable and have a long life. Costs, while slightly higher than for D-19, are negligible compared to the saving in telescope time. Publication: The Astronomical Journal Pub Date: March 1962 DOI: 10.1086/108818 Bibcode: 1962AJ.....67Q.272F full text sources ADS |

HISTOCHEMICAL DEMONSTRATION OF UNSATURATED LIPIDS BY A BROMINE-SILVER METHOD

A new method for the histochemical demonstration of unsaturated lipids having a sounder chemical basis than previously reported methods has been developed. Formalin fixed frozen sections are treated with aqueous KBr3; silver bromide is precipitated at the site of bromination by treatment with silver nitrate in dilute nitric acid; free silver is then formed by reduction with a photographic developer. Specificity is shown by the abolition of staining following any of these control reactions: a) elimination of the bromination step; b) prior blockade of double bonds with performic acid; c) extraction of lipids with chloroform-methanol or d) extraction of silver bromide before development with thiosulfate or cyanide solutions. In addition to normal tissues, atherosclerotic tissues and sections of central nervous tissues exhibiting lipid dystrophies have been examined. This technique has been fully demonstrated on pure compounds deposited on filter paper. Hydrogenated or performic acid treated compounds give negative results.

Paper Electrophoresis

The physical developer technique is a means to detect fingerprints on dry and wet, porous items, including paper articles, clay-based products and adhesive tapes. The process involves an oxidation–reduction couple whereby a solution of an iron salt reduces aqueous silver nitrate to finely divided metallic silver. The technique derives its name from the photographic physical developer which, during processing of film rolls, undergoes a similar redox reaction. The physical developer reveals the fingerprints as dark gray or black images due to the adsorption of metallic silver particles on the fatty acid and lipid components of sweat residue.

分光学的方法による現像液中の1-フェニル-3-ピラゾリドンの迅速定量法

分光学的方法による現像液中の1-フェニル-3-ピラゾリドンの迅速定量法

Antioxidants. The Microdetermination of Hydroquinone

A new titrimetric method for the microdetermination of hydroquinone is described. This method is recommended for the assay of fats and oils, photographic developers, and ether anesthetics. The assay is carried out within limits of 0.5 to 2 mg, of hydroquinone. The procedure is quite simple and rapid but yet shows relatively high accuracy over the suggested range. The experimental error does not exceed ±2 per cent.

Application of Photographic Developer for the Histochemical Demonstration of Blood Leucocytes by the Metal Salt Technique

A modified method of the calcium silver technique for demonstration of alkaline phosphatase in blood cells on smear by Takeuchi's method was attempted by application of photographic developer instead of Kossa's reaction in the original procedure.

Leukoderma with Loss of Hair.? Due to Photographic Developer

Leukoderma with Loss of Hair.? Due to Photographic Developer

Electronic-Recording, Time-Resolving Spectrometer*

A photoelectric means for recording an extended spectral region as a function of time has been developed. With this method, the recording procedure imposes no limitations on the time resolution other than that defined by the minimum detectable energy. The optical portion of the device, which includes the time-resolving mechanism, is very similar to a conventional photographic time-resolving spectrograph. However, the photographic plate has been replaced by a television camera which is used in much the same way. In fact, direct analogies can be drawn between the photographic plate and the storage surface of the television camera tube and also between the photographic developer and the scanning electron beam in the camera tube. The method is capable of sensitivities of the order of 103 times those available with Tri-X film in the visible. In addition, the usual cumbersome photographic calibration procedures are avoided since intensities are recorded as vertical deflections, yielding records similar in appearance to those obtained from strip chart recorders.

Demonstration of alkaline phosphatase and periodic acid-Schiff positive material in the same section.

Alkaline phosphatase activity and periodic acid-Schiff (PAS) positive material were demonstrated in the same section by producing a gold-toned silver deposit at the sites of enzyme activity, followed by the PAS reaction. The glycerophosphate incubating mixture was modified by substituting AgNO3 (final concentration about 0.17%) for the magnesium salt, and, after a slightly lengthened incubation, the silver was reduced by means of a fine grain photographic developer. Gold toning was followed by the regular PAS staining procedure. Gold deposits in the sites of enzyme activity were fully resistant to the action of periodic acid.

Idophil components of insect cuticle.

Deparaffinized sections, after hydration, are successively immersed in the following aqueous solutions: 1% iodine in 2% potassium iodide (10 min), 1% silver nitrate (10 min), any fine-grain commercial photographic developer (10 min), 0.1% gold chloride (15 min), 5% sodium thiosulphate (2 min), and 1 % potassium metabisulphite acidified with a little hydrochloric acid (2 min). Thorough washing after each immersion, to ensure removal of all water-soluble material, is essential before proceeding to the next stage. Only chemically-clean staining vessels should be used. After dehydration, the sections may be mounted in any desired medium. Iodophil regions of the cuticle are stained deep purple to black; the remainder of the cuticle is unstained. Since the stain is formed by metallic deposits, the colors are permanent.

A Note on the Estimation of Sodium Carbonate in Photographic Developers

A procedure for the estimation of sodium carbonate in photographic developers to within ± is given. The carbonate is precipitated as barium carbonate and titrated with a standard acid solution.