Colors, views

Quality control on-site, or swatches sent remotely. Color viewing conditions will vary between countries and may vary between different spots in the same office, according to illuminating, shading, and reflecting conditions both inside and from outside through doors and windows. 

A dedicated software package developed to meet the need of colour analysis has been introduced by Bio-Tek Kontron Instruments, UK. Named Color View, it enables the user to define basic parameters, such as observation degree and illuminant. The user can also customize an illuminant definition. Colour analysis is achieved using a choice of evaluation modes from an extensive list of options. The colour comparison function in the equipment determines the difference between two samples, calculated according to the evaluation modes selected by the user,... 

In colored cathode ray tubes (CRTs), such as those used in televisions and computer terminals, three electron gun beams are focused on three different sets of phosphor dots on the front face of the tube. The dots are produced by using a compHcated photoHthography process. The phosphor dots are produced by settling the three different phosphors, each of which emits one of the primary saturated colors, red, green, or blue. Each phosphor is deposited separately and the three dots in each set are closely spaced so that the three primary colors are not resolved at normal viewing distances. Instead the viewer has the impression that there is only one color, the color achieved when the three primary colors are added together. 

Theory and Equipment. Many diseases of the human body can be identified by visual appearance. Tumors in the upper gastrointestinal (GI) tract, for example, possess a characteristic salmon pink color (3). The presence of such a color can be an indication of disease. Endoscopy is the medical imaging tool used to detect such colors in the inside of hoUow internal organs such as the rectum, urethra, urinary bladder, stomach, colon, etc. An endoscope is the instmment used to perform endoscopy. Endoscopic imaging involves the production of a tme color picture of the inside of the human body using lenses and either hoUow pipes, a fiber optic bundle, or a smaU CCD camera. AU three use a large field-of-view, sometimes referred to as a fish eye, lens to aUow a 180° field of view. 

Mercuric Oxide. Mercuric oxide[21908-53-2] HgO, is a red or yellow water-insoluble powder, rhombic in shape when viewed microscopically. The color and shade depend on particle size. The finer particles (< 5 -lm) appear yellow the coarser particles (> 8 -lm) appear redder. The product is soluble in most acids, organic and inorganic, but the yellow form, which has greater surface area, is more reactive and dissolves more readily. Mercuric oxide decomposes at 332°C and has a high (11.1) specific gravity. 

The reduction of molybdate salts in acidic solutions leads to the formation of the molybdenum blues (9). Reductants include dithionite, staimous ion, hydrazine, and ascorbate. The molybdenum blues are mixed-valence compounds where the blue color presumably arises from the intervalence Mo(V) — Mo(VI) electronic transition. These can be viewed as intermediate members of the class of mixed oxy hydroxides the end members of which are Mo(VI)02 and Mo(V)0(OH)2 [27845-91-6]. MoO and Mo(VI) solutions have been used as effective detectors of reductants because formation of the blue color can be monitored spectrophotometrically. The nonprotonic oxides of average oxidation state between V and VI are the molybdenum bronzes, known for their metallic luster and used in the formulation of bronze paints (see Paint). 

Iron Oxide Yellows. From a chemical point of view, synthetic iron oxide yellows, also known as iron gelbs, are based on the iron(III) oxide—hydroxide, a-FeO(OH), known as goethite. Color varies from light yellows to dark buffs and is primarily determined by particle size, which is usually between 0.1 and 0.8 p.m. Because of their resistance to alkahes, these are used by the building industry to color cement. Thermally, iron oxide yellows are stable up to 177°C above this temperature they dehydrate to iron(III) oxide ... 

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