Control colours

The optical shutter described above can function as a voltage-controlled colour filter. The PLZT is again of the slim-loop quadratic variety, and the polarizer-PLZT-analyser configuration as for the shutter. 

Multiple choice determination device Eive electronically controlled coloured light pulses (yellow, red, green, blue, white) are activated in alternating sequences. Pressing a button with the same colour indicates that the test person has recognized and registered the colour both instantly and correctly. This device has proved to be a useful instrument in clinical testing environments. (14)... 

Vinyl stabilisers can either be liquids or solids and formulated as single or mixtures into PVC products. They can be combinations of metal salts and organic additives added to improve shelf life, prevent degradation and control colour of finished products. Depending on the application, the stabiliser compositions are based on organometal salts of Sn, Ba, Cd, Pb, P, Ti, etc. Analysis of these salts is often required to provide certification that the metallic composition of the product agrees with established specifications of the products. 

This CVS method uses CIE (L-a-b) colour space. The reason is that CIE space can control colour and intensity information more independently than RGB colour space. This colour space is especially efficient in the measurement of small colour changes, as a result direct colour comparison can be performed based on geometric separation within this colour space [12]. 

Zheng Z, Zhu J, Graee JR, Lim CJ, Brereton CMH. Particle motion in drculating and revolving fluidized beds via microcomputer-controlled colour-stroboscopic photography. In Potter OE, Nicklin DJ, eds. Fluidization VII. New York Engineering Foundation, 1992, pp 781-789. 

A number of controls are provided to enable the user to tailor the colour, scale and orientation of the displayed image to highlight details of interest. Two types of colour map are available. The Default colour map is a cold-to-hot scheme in which with cold colours such as blue used for low amplitudes and hot colours such as red, yellow and white used for high amplitudes. The Mono colour map uses intensities of red, from black upwards, to indicate increasing amplitude. 

The modem era of biochemistry and molecular biology has been shaped not least by the isolation and characterization of individual molecules. Recently, however, more and more polyfunctional macromolecular complexes are being discovered, including nonrandomly codistributed membrane-bound proteins [41], These are made up of several individual proteins, which can assemble spontaneously, possibly in the presence of a lipid membrane or an element of the cytoskeleton [42] which are themselves supramolecular complexes. Some of these complexes, e.g. snail haemocyanin [4o], are merely assembled from a very large number of identical subunits vimses are much larger and more elaborate and we are still some way from understanding the processes controlling the assembly of the wonderfully intricate and beautiful stmctures responsible for the iridescent colours of butterflies and moths [44]. 

Take two test-tubes A and B in A place about 5 ml. of neutralised tartaric acid solution and in B place 5 ml. of distilled water. To each solution add 3-4 drops of ferric chloride solution. Place a piece of white paper under the tubes, look down their length and note that A is definitely yellow compared with the control tube B. This yellow colour is given by a-hydroxy-carboxylic-acids, lactic acid, tartaric acid, citric acid. 

The contents of B, which act as a control, are treated with mercuric chloride in order to inhibit the action of the enzyme, and then 10 ml. of urease solution are added. The solution is diluted with water and ammonium chloride added (in order to balance the ammonium chloride subsequently formed in A). Meth) l-red is then added and the solution is titrated with Mj 10 HCl from a second burette B until a bright red colour is obtained. 

Dissolve 46-5 g. (45-5 ml.) of aniUne in a mixture of 126 ml. of concentrated hydrochloric acid and 126 ml. of water contained in a 1-htre beaker. Cool to 0-5° in a bath of ice and salt, and add a solution of 36-5 g. of sodium nitrite in 75 ml. of water in small portions stir vigorously with a thermometer (1) and maintain the temperature below 10°, but preferably at about 5° by the addition of a httle crushed ice if necessary. The diazotisation is complete when a drop of the solution diluted with 3-4 drops of water gives an immediate blue colouration with potassium iodide - starch paper the test should be performed 3-4 minutes after the last addition of the nitrite solution. Prepare a solution of 76 g. of sodium fluoborate (2) in 150 ml. of water, cool, and add the chilled solution slowly to the diazonium salt solution the latter must be kept well stirred (1) and the temperature controlled so that it is below 10°. Allow to stand for 10 minutes with frequent stirring. Filter... 

C. R. Bamford, Colour Generation and Control in Glass, Elsevier Scientific Publishing Co., New York, 1977, pp. 141—164. 

J. Berry, "Control of Volatile Organic Compound (V OC) Emissions from Painting Operations ia the United States," Polymers Paint Colour J. 181(4281), (Apr. 17,1991). 

J. Houk, M. J. Doa, M. Dezube, and J. M. Rovinski, "Evaluation of Dyes Submitted Under the Toxic Substance Control Act New Chemicals Programme," Colour Chemistry, Elsevier AppHed Science, London and New York, 1991. 

For easy identification and prompt maintenance it is mandatory to segregate all control wires when they are carrying more than one control supply (e.g. at different voltages and both a.c. and d.c.), and run them in separate bunches. The control wires must also be of different colours for different control supplies. The colour codes have been standardized for different control supplies (refer to lEC 60445). 

Unless great care is taken in control of phenol/acetone ratios, reaction conditions and the use of catalysts, a number of undesirable by-products may be obtained such as the o-,p- and o-,o- isomers of bis-phenol A and certain chroman-type structures. Although tolerable when the bis-phenol A is used in epoxy resins, these have adverse effects on both physical properties and the colour of polycarbonate resins. 

The stabilised nitrate may then be bleached with sodium hypochlorite, centrifuged to remove much of the water in which the polymer has been slurried and dehydrated by displacement with alcohol while under pressure in a press. It is interesting to note that in these processes approximately 35 000 gallons (160000 litres) of water are used for every ton of cellulose nitrate produced. Control of purity of the water is important in particular the iron content should be as low as 0.03 parts per million since iron can adversely affect both the colour and heat stability of the polymer. 

Quality control tests on the resins most commonly employed are for specific gravity, viscosity, colour, clarity and gel time under standard conditions,... 

The drying of the curd is completed by passing through a rotary drier such as the Pillet-Bordeaux. In this machine the curd passes down a chute with hot air running counter to the direction of flow of material. Strict temperature control is essential, the maximum discharge temperature being below 65°C. If such control is not made then the resin will be dark in colour. 

Colour (R) Legislation and controls Visual comparison ASTM methods... 

---