Value, color

To display properties on molecular surfaces, two different approaches are applied. One method assigns color codes to each grid point of the surface. The grid points are connected to lines chicken-wire) or to surfaces (solid sphere) and then the color values are interpolated onto a color gradient [200]. The second method projects colored textures onto the surface [202, 203] and is mostly used to display such properties as electrostatic potentials, polarizability, hydrophobidty, and spin density. 

Lightfastness is measured by exposing pigmented film to an artificial or natural, eg, Florida exposure, light for a predetermined time. It is a relative term where the color of a sample exposed to a known light source is compared to its original color values. To make it meaningful, aH conditions of the exposure have to be weH defined. 

Thus, the presence of a thiamine ring in Cl Sulfur Blue 9 was conclusively proved. The thiamine ring is the fundamental chromophore that accounts for the high color value of both the sulfur dye and Methylene Blue [61-73-4] including their abiUty to form pale yeUow leuco forms on reduction. Methylene Violet (15) is obtained from Methylene Blue (16) by hydrolysis in boiling alkah. 

Liquids. Some Hquid dyes are made directly from the thionation melt by additions of caustic soda and sodium hydrosulfide. Hydrotropic substances are sometimes added, either at the initial thionation stage or after the polysulfide melt is finished in order to keep the reduced dye in solution. Pardy reduced Hquids are also available. They are usually more concentrated than fully reduced Hquids, thus saving packaging and transportation costs. However, they require a further addition of reducing agent to the dyebath in order to obtain full color value. On the other hand, fully reduced Hquids are... 

Typically, grape skin extract has a specific gravity of 1.13 g/mL at 20°C, a solids content of 28—32° Brix (=t3°), a pH of 3.0, and a color strength as anthocyanin of about 1.25% (as measured at 520 nm ia pH 3.0 citrate buffet). Grape skin extract is also available as spray-dried powders with color values three to four times those of the liquid. The properties and uses of grape skin extract ate similar to those of grape color extract. 

Ben2anthrone acridones play an important role in vat dyes, since they give from dark green to oHve green shade and have a high color value and excellent fastness. Examples are given in Table 6. 

Clear, surface-active phosphate ester compositions were prepared by heating 1 mol P4O,0 with 2-4.5 mol of a linear or branched chain C6, 8 saturated alcohol, a C4 20 mono- or dialkylphenol, or a 2- to 14-mol ethylene oxide adduct of one of these alcohols or alkylphenols at 25-110°C, and hydrolyzing the reaction product at 60-110°C with 0.5-3.0% H20. The hydrolyzed mixture had a lower Klett color value than the phosphorylation reaction mixture [21]. 

Colorless phosphate ester surfactants were also prepared by treating P4O,0 with an organic OH-containing compound in the presence of a phosphinic acid color inhibitor, e.g., bis(hydroxymethyl)phosphinic acid color inhibitor. Thus, 558 parts dodecanol containing 2.4 parts of phosphinic acid color inhibitor was treated with 142 parts P4O10 at 100-135°C. The phosphate ester surfactant had a VCS color value of 1, whereas a sample prepared without the color inhibitor had a VCS color value of 5. Twenty-eight similar surfactants were prepared using various alcohols and alcohol-alkylene oxide condensates [22]. 

Tests were carried out as designated in ASTM Method D-925-83 related to staining of surfaces by contact, migration, or by diffusion. Hunter color values were measured on the L-scale. On this scale 100 is white and 0 is black. 

Ameny MA and Wilson PW. 1997. Relationship between hunter color values and 3-carotene contents in white-fleshed African sweetpotatoes (Ipomoea batatas Lam). J Sci Food Agric 73 301—306. 

CIE color system, 7 304. See also Commission Internationale de l clairage (CIE) chromacity diagrams, 7 313-315 standard illuminants, 7 315-316 CIEDE200 color difference equation, 7 322 CIELAB, 7 304 CIELAB Color Space, 7 320 CIELAB color values, of flax fiber, 11 614t Cielab dye nomenclature system, 9 244 CIELAB Metric Color Spaces, 7 320 CIELAB system, 19 428, 451 CIELUV Color Space, 7 319-320 CIE Standard Observer, 7 311-312 Cigarette filters... 

Pumpkin Quick Bread, Previous research yielded legume breads and bread products with decreased flavor, volume, and color values (14,30-31). The present research attempted to overcome these... 

The lightfastness of a material is defined by the inherent ability of a given pigment-vehicle system to retain its initial color value upon exposure to daylight. It is thus a system-related parameter which cannot be determined in connection with pure pigment only. 

This is especially true in industrial and urban areas. Fig. 87 shows a paint containing Chrome Yellow, which was subjected to a test as described in Section 1.6.2.2 treatment with 1 N sulfuric acid for one hour at 70°C. The distinct color change on the circular test area is accompanied by a considerable gloss reduction. In the corresponding lead chromate-free system, it is only the binder that is affected, which reduces the gloss the color value on the other hand is retained. 

P.R.12 textile prints are excellently lightfast 1/1 to 1/6 SD prints equal step 7 and 6-7, respectively, on the Blue Scale. However, the pigment fails dry cleaning tests and migrates considerably in PVC coatings. P.R.12 tolerates dry heat up to 150°C at 180°C, the pigment still largely retains its initial color value. 

As far as heat stability goes, P.R.146 retains its color value for 10 minutes at 200°C or for 30 minutes at 180°C it thus scores 20°C higher than P.R.57 1.1/1 and 1/3 SD letterpress proof prints equal step 5 on the Blue Scale for lightfastness, while 1/25 SD specimens match step 4. P.R.146 is thus 1/2 to 1 step on the Blue Scale more lightfast than P.R.57 1. Prints made from commercially available types are semitransparent. 

Incorporated in finishes, P.Gr.8 is heat stable up to about 180°C. It is not entirely fast to overcoating. Most systems containing P.Gr.8 will fail to maintain their color value if they are exposed to acids there is a shift towards yellower hues, a phenomenon which is attributed to demetallation of the pigment. 

With good fuels (charcoal or active metals), potassium nitrate will burn well. Its use in colored flame compositions is limited, primarily due to low reaction temperatures. Magnesium may be added to these mixtures to raise the temperature (and hence the light intensity), but the color value is diminished by "black body" emission from solid MgO. 

For Duchamp, additionally this primary black-to-white combination symbolically signifies la valeur coloree de matiere of each component which eventually has to disappear. As signalled by Duchamp, one can in fact identify the composition of each significant bit of matter in later, or further developed, stages of their operation by their respective color values white, black, red (blanc, noir, vermiUon). In a slightly different order, these three... 

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