Specimen Color

Many one-, two-, and three-dimensional systems have been developed over the years to order colors ia a systematic way and provide specimen colors for visual comparison. Coordination has now been achieved with computet programs between essentially all of these systems and the CIE systems described below and conversions can easily be made between them. 

Three areas of expertise are involved in measurement techniques. First is specifying the specimen color parameters necessary to satisfy the customer (80). Second is taking actions to ensure maximum precision from measuring... 

Selecting a standard illuminant, a standard observer, and the proper expression of results is essential to obtaining color data that correspond to color perception. However, because instruments are simple to operate, many operators are untrained in instrument and color theory. They make bad parameter choices or instrument adjustments and measure specimen colors incorrectly (30). If the operator can define the color task, he or she will probably choose the correct variables and solve his or her color mea-... 

Slow losses of accuracy are particularly insidious when the instrument and specimens are changing. It is a good idea to calculate specimen color along with solar data to rule out instrument variations. For example, cloth... 

The temperature decisive for weathering resistance is not the temperature of ambient air, but the temperature of the specimen, Figure 2.7. Due to the absorption of solar radiation it can be considerably above the temperature of the ambient temperature. The degree of absorption of sunlight radiation and the resulting temperature are dependent on specimen color, i.e., one and the same base material in different colorations - independent of any other influence of coloration on material stability - can lead to different, thermally determined values of weathering resistance, see Table 2.10. 

Determined by comparison of test specimen color in non-exposed state versus test specimen at stated exposure level. 

The tables 5 and 6 give the results of sensitivity tests obtained on the nickel-chromium specimens of 20 and 10 pm for the fluorescent range products, and of 50 and 30 pm for the colored range of products. 

Dry Cleaning. In colorfastness to dry cleaning, ISO 105-D01 a specimen of the textile is placed in a cotton fabric bag together with stainless steel disks and agitated in perchloroethylene (30 min, 20°C) and the effect of the shade and the color of the solvent assessed using the grey scale. 

Golorfastness to Atmospheric Contaminants. The test colorfastness to nitrogen oxides, ISO 105-G01 is to assess the fastness of the color to nitrogen oxides that may be present ia hot air that has been passed over heated filaments or from the burning of gas, coal, etc. Specimens are exposed to nitrogen oxides ia a closed container along with standards until the standards have changed to a predetermined extent. 

With polarizers fidly crossed and the specimen rotated to maximum brightness, the sample thickness is determined with the aid of a calibrated eyepiece micrometer, and the polarization (retardation) color is noted. From these the birefringence may be determined mathematically or graphically with the aid of a Michel-L vy chart. 

Alkalinity. To 25ml of w, add 1 drop of 0.1% methyl red indicator soln (60% ale) and 0.0 IN acid or base until the soln is just pink. Add 25ml of specimen, mix well, then titrate with 0.01N sulfuric acid until the pink color is restored. Calc the % NH3 by wt as follows ... 

DIARRHEA AND DEFICIENT FLUID VOLUME The nurse records the number, character, and color of stools passed. Daily stool specimens may be ordered to be sent to die laboratory for examination. The nurse immediately delivers all stool specimens saved for examination to die laboratory because the organisms die (and therefore cannot be seen microscopically) when die specimen cools. The nurse should inform laboratory personnel diat the patient has amebiasis because die specimen must be kept at or near body temperature until examined under a microscope... 

Bilirubin. The most widely used method for bilirubin continues to be the method which couples bilirubin with the diazo reagent and reads the color formed (38). Unfortunately the sensitivity of this procedure is such that a lower limit of approximately 10 microliters of specimen is a limitation on the use of this procedure. 

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