Colour specification

Potassium permanganate and iodine, which are important redox reagents, are both self-indicating, i.e. the colour of the reagent in each case is intense and will impart a perceptible colour to a solution when present in very small excess. One drop of a solution of potassium permanganate (0.02 mol dm 3) can be detected in a titrand solution of 100 cm3, and a similar amount of iodine by shaking the titrand with 5 cm3 of chloroform or carbon tetrachloride to produce an intense purple colour. Specific indicators react in a specific manner with one participant in the reaction. The best examples are starch, which produces an intense blue colour with iodine and potassium thiocyanate, which forms an intense red compound with iron(III). 

Entrainment is kept at a minimum by a wash oil section in the vacuum unit and checked with a colour specification on the FCC feed. The "real" FCC resid cracking seems to start, when the wash oil stream in the vacuum column is also routed to the FCC unit, obviously the colourof the FCC feed will deteriorate strongly. 

Poster 25. Masanori Sakaguchi, Rie Endo and Masahiro Susa (Tokyo Institute of Technology) Synthesis of New Coloured Alloys Based upon Colour Specification and Density of States... 

Plates—Need to be made from the artwork, one per colour specifically designed for the machine on which it is going to be used. 

Introduction colour specification systems and colour appearance models... 

The original CIE system of colorimetry was designed for colour specification and has only limited use as a colour-appearance model. It can be easily shown that the CIE tristimulus values that can be used effectively to specify a surface colour do not correlate well with the appearance of that surface. This chapter introduces the distinction between colour specification and colour appearance and then reviews how simple adaptive processes that pool information at different spatial positions in an image can be used as a basis for colour-appearance models. A typical colour-appearance model, CIECAM97S, is then described. Finally, some further uses of colour-appearance models are discussed. 

Mathematical approaches that make use of concepts associated with colour space for colour measurement and specification based on reflectance spectroscopy have become well-established. Indeed the calculations involved are normally implemented in the software that is provided within an instrument used for colour measurement. The basis of all colour measurement systems is the CIE system of colour specification, which was agreed in 1931. The Commission Internationale de I Eclairage (CIE) is an international organisation promoting cooperation and information exchange on matters relating to the science and art of lighting. An important approach used for the... 

It is essential to cool the ageing vessel and hydrolyser during the manufacture of alkylbenzene sulphonic acids. Although manual control of the cooling water flow-rate to the ageing vessel in particular is often adequate, a flow indicator should be installed in the cooling water line and a temperature indicator in the product outlet line to enable the operator to adjust the cooling water flow-rate effectively. Where strict acid colour specification must be adhered to, the installation of an automatic temperature control system may be justified. 

The XYZ system of colour specification was recommended by the CIE in 1931 and was closely based on the RGB system. The difference lies in the fact that R, G and B were real light sources of known specifications. X, Y and Z are theoretical sources which are more saturated than any real light source, and allow matching of any real colour using positive amounts of the three primary sources. The X, Y and Z stimuli are defined so that ... 

Alternatively, XYZ values may be calculated from reflectance values using similar equations to those for RGB, but using weighting functions jc(2, y(X) and z(2) in place of r(2), (A) and fc(2). The CIE nomenclature is to denote the 10° observer function with a subscripted 10 (Eqn (3)). The XYZ system is an improvement over the RGB system in that it eliminates negative numbers in colour specification. However, it is still based on the mixing of coloured lights and not on the visual appreciation of colour. In particular, the visual colour difference between two samples is not linearly related to the difference in XYZ values ... 

Since L a b values for a sample may change for a different illuminant and observer combination, any colour specification must always include the illuminant and observer for which the values were calculated. 

To illustrate the use of LDA for food authentication, an example involving the classification of honey samples according to their floral origin will be used [15]. In particular, the data set comprises the results of 15 determinations— pH free, lactone, and total acidity diastase water content specific conductivity dextrose, fiructose and DP2 colour specific rotation hydroxymethyl-furfural (HMF) content and (on the whole sample and on the... 

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