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This article analyses the effect of industrial fluoride air pollutants on the phenolic contents of Norway spruce needles. Potted Norway spruce trees of two clones were exposed under natural conditions at various distances from an industrial fluoride source. The new needles were analyzed periodically over a year for their phenolic content. Three different quantitative colorimetric tests were used to identify different groups of phenolic compounds. All three methods gave consistent results that the group of trees closest to the fluoride source was found to contain the highest amounts of phenols.

The importance of the discoloration of wool is indicated by the volume of a colour space, which theoretically may be obtained by dyeing the discoloured wool. This obtainable volume (OV) is difficult to calculate, and some simple combinations of the measurements made with a colorimeter are therefore compared with OV. For a range of wool samples from seven countries, several whiteness indices were compared with OV values calculated for the CIE x, y, Y colour space, the Adams-Nickerson space, and the Glasser 'cube-root' space. Reflectance values at single wave-lengths were substituted in the whiteness formulae, and these results were also compared with OV values. Several of the formulae give a near-perfect correlation with OV. [ABSTRACT FROM AUTHOR]

This first of a two-part series on international test methods for colorfastness discusses the necessity and desirability of international standardization, and reviews the role played by the International Organization for Standardization in developing test methods used throughout the world. A comparison is given of ISO and AATCC test methods for colorfastness of textiles. General principles of testing, tolerances and assessment of colorfastness are covered, followed by comparisons of the scope and principles of individual ISO and AATCC test methods for evaluating colorfastness to acids and alkalis, bleaching, carbonizing, light, mercerizing and metals in the dyebath. [ABSTRACT FROM AUTHOR]

A general procedure is detailed for determining dye strength of a sample relative to a standard from measurement of the spectral reflectance factor of dyeings. Relative dye strength is calculated from the ratio of specific absorption function values for sample and standard. The specific absorption function used is the Kubelka-Munk function K/ at a selected wavelength, divided by the amount of dye on a unit weight of substrate. Problems associated with dye application, sample presentation and measurement are discussed. Precision and accuracy of the method are dealt with from the standpoint of both dyeing and spectrophotometric measurement. [ABSTRACT FROM AUTHOR]

Limitations of computer color matching for textiles and the chances to overcome these limitations by improved techniques are discussed. The most serious limitations in the accuracy of the matches are those imposed by variations in dyeing conditions and textile materials. These can hardly be solved by development of general theories, but only by new calibration dyeings or by approximations such as a test dyeing. General improvements in the theory used for the calculations today would have only a minor bearing on the whole process. [ABSTRACT FROM AUTHOR]

This is the second of a two-part review on the measurement of color and color differences. It was written to be part of a technical handbook on AATCC test methods. It presents the theoretical background on color that is needed to understand fully the color evaluations included in the AATCC test methods. The Gray Scale for Color Change and the AATCC Chromatic Transference Scale are discussed in detail. Certain special aspects of color, including whiteness, fluorescence, iridescence, flare, metamerism and color mixing are reviewed. [ABSTRACT FROM AUTHOR]

The tryptophan contents of human serum transferrin and human lactotransferrin have been estimated by colorimetric and spectrophotometric procedures. The nine tryptophan residues of human serum transferrin have been modified by 2-nitrophenylsulphenyl chloride in 30% acetic acid, 2-hydroxy-5-nitrobenzyl bromide at pH 3 and dimethyl-(2-hydroxy-5-nitrobenzyl)-sulphonium bromide at pH 7.6. Upon modification under acidic conditions the iron-binding capacity falls off linearly with degree of modification. At pH 7.6 no fall off in iron-binding capacity was observed with a maximum of 8.4 2-hydroxy-5-nitrobenzyl residues bound per molecule of transferrin. The results have been interpreted as showing that tryptophan residues are not directly involved in the iron-binding sites of transferrin. [ABSTRACT FROM AUTHOR]

This section presents abstracts of studies related to police science. In the article Spectrophotometric Determination of Fluoride, by E. D. Schall and H. G. Williamson, the method described adapts the bleaching of the colored complex of titanium and ascorbic acid by fluorine to quantitatively estimate fluoride. The article Identification of Rodent Fur Hairs, by Dorothy B. Scott described and illustrated the differentiating characteristics of the medullary unit of hairs from rat or mouse, rabbit, squirrel, and muskrat. A scheme of analysis for lipstick is outlined in the article Analysis of Lipstick, by John E. Clement. The article Principles of Precision Colorimetry, Charles N. Reilley and Crayton M. Crawford, discuss the effects of slit width, sensitivity, and dark-current knob setting on spectrophotometric precision.

The article presents a colorimetric method for determining the amylolysis of saliva. Previous studies that have implemented colorimetric approaches for measuring amylolysis activity are discussed. The authors were interested in devising a new method for conducting this measurement of activity. Their findings indicated that variations in the amylolysis of the saliva exist on an individual basis.

Experiments have demonstrated the possibility of analyzing for urea in geologic-type specimens by reflectance from paper-phase enzymatic color reactions. This serves as a plausible system that can be employed in the extraterrestrial search for evidence of biological or prebiological phenomena. [ABSTRACT FROM AUTHOR]

A method of measuring the degree of discoloration of scoured wool is described. The results are related to the basic commercial disadvantage of wool yellowness, namely, the resulting restriction in the shade range that can be produced by dyeing, and hence the maximum volume of the CIE 10° Standard Observer colour space that is theoretically obtainable by subtractive coloration (dyeing) is given as an absolute measure of the level of discoloration. This obtainable volume (OV) is calculated for two Australian wools and a ‘perfect-white’ substrate. [ABSTRACT FROM AUTHOR]

An account is given of the use of tristimulus colorimetry to specify the colours of Australian wools. Greasy wools, scoured wools, scouring liquor, and fabrics were measured, and the results are expressed by means of polar co-ordinates. The radial measure in the Hunter (α, β) colour space, that is, saturation, indicates the degree of discoloration. It is shown that, with the widely used yellowness-index formula, 100 (X-Z)/Y, the results obtained have a linear relationship with saturation. This index may therefore be used as a single-co-ordinate measure of the yellowness of Australian wools and of fabrics that have been bleached or yellowed. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about a research paper entitled "A Pressed-disk Technique for Preparing Wool Samples for Yellowness Measurement," by D. B. Green, A. S. Little and W. Parkin.

Explores the effects of analgesics and tranquilizer-sedatives on the measurement of adrenal hormones in the urine. Methods used in the analysis of urine; Influence of propoxyphene on catecholamine excretion; Information on the acid-fluorescence procedure; Description of the magnitude of urine during the ingestion of propoxyphene.

Complementary tristimulus colorimetry applied to colorants in solution provides quality control parameters applicable to both manufacturer and consumer. Instrument requirements, techniques and solvent systems are described for determining the shade, strength and brightness of many dyes without actually dyeing. Dyeings can be made at a predetermined equal depth regardless of shade, and shade tolerances can be established based on color composition with a minimum of dye testing. [ABSTRACT FROM AUTHOR]

Measuring the color of a fluorescent substance requires a special type of optical arrangement not found in all spectrophotometers or colorimeters. Even with the correct optics, the measurement only holds for the particular light source which was used. This restriction sets fluorescence measurement apart from ordinary color measurement, the results of which can be applied to any light source with the proper calculation. By special techniques it is possible to separate out the fluorescence portion of the color from the reflectance portion. Such a separation is valuable for theoretical studies (for example, quantum efficiency determination) or practical studies (for example, how much detergent whitening is brought about by real cleaning and how much by action of fluorescent whitening agent). An interesting application of fluorescence colorimetry is in the study of fluorescent whitening agents and the explanation of the different modes of action of green-shade and red-shade whiteners. [ABSTRACT FROM AUTHOR]

This general procedure describes in detail the spectrophotometric measurement of dye strength in solution. The method is primarily an analytical technique and does not describe color. Solutions of the dye are prepared with selected solvents and additives to promote solution stability. The solutions are aliquoted and diluted to a measurable concentration and the absorbance (or transmittance) curve is obtained on a spectrophotometer. The absorptivity of the dye measured is then compared (in ratio) to the absorptivity of a standard dye measured in an identical manner. The method points out that the strength of dyes determined by this procedure is usually consistent with strength determined by dyeing but there are notable exceptions. Precision and accuracy of the method is dealt with as well as the solution and instrumental variables encountered. Discussion of sampling and the standard sample is covered as is choice of buffers and solvents. The method details solution preparation techniques, measurement procedures and the calculations necessary to express dye strength numerically. [ABSTRACT FROM AUTHOR]

The use of color difference formulas in the textile industry is somewhat hampered by the relatively low degree of correlation obtained between color differences calculated with a color difference formula and average visual judgment as represented by acceptability judgments of matches around standards. Best results in practical work could be expected from a formula based on ellipses representing the average visual judgment of a group of observers. Not enough data exist presently to make such a formula possible. This investigation adds significantly to existing acceptability data. Acceptabilities for a total of 180 samples around ten standards, located mostly in areas of color space where no such data existed, have been determined. from judgments under artificial day-light by 16 skilled observers. Approximate 50% acceptability contours developed from this data fit in well with contours of previously published data. Two areas of sudden discontinuity in the direction of the major axis of the acceptability ellipses were found at dominant wavelengths of approximately 494 and 570 nm and may be of significance for the theory of color Vision. Sixty-four samples around four standards were also observed and judged Under incandescent light. No significant difference in acceptability judgment Under tungsten light as compared to daylight could be detected. [ABSTRACT FROM AUTHOR]

Spectrophotometric absorption measurements of colored solutions can be related to CIE Colorinietry. The area of an absorption curve is measured with a tristimulus intergrator and used to define the strength of the dye. The tristiinulus values are reduced to co-ordinates that locate the dye at a specific place on a color diagram. These two physical constants (strength and hue) are used to match aye mixtures by graphical methods or by titration. [ABSTRACT FROM AUTHOR]

Instrumental shade sorting of textile samples offers the advantages of consistency and a simple shade order system. A special purpose computer, integral with a unique, four-filter tristimulus colorimeter, has been developed to suit the specific requirements of textile production shade sorting. Samples may be evaluated under llluminant A and/or C conditions, to uniform visual appearance difference tolerances, regardless of hue, saturation or lightness. The human engineering considerations and design concept of the instrument system are briefly discussed, as is the simple procedure for programming the computer for the evaluation task. Mill experience with the instrumental shade sorting system indicates excellent agreement with visual judgment with greatly improved uniformity of classification. Economic advantages gained through reduced customer complaints and improved process feedback information is discussed in detail. [ABSTRACT FROM AUTHOR]

This paper discusses the practical use of a computer for color matching. The author describes his experience with instrumental color measurement and matching since 1954. Problems involved in computerizing a dye system are presented, with an emphasis on practical application. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to predict from optical principles the color of cloth, thickness of cloth and color of background which will permit the smallest amount of mineral oil in a spot to be determined. It is found that the fabric should be opaque for maximum effect but a black background is preferable if the cloth is semi-transparent For colorimeters operating on a linear potentiometer principle, the optimum color is gray with a reflectance of 41.4%, For the General Electric spectrophotometer that operates with a Martens photometer, the optimum color is gray with a reflectance of 33.3%. For visual evaluation a gray should have a reflectance of 19%. A method is described for determining the concentration of any dye formula having a fixed ratio of dyes which will produce the maximum visual effect of an oil stain on opaque fabrics. An SOB index (soil on black) is proposed to give the relative visibility of oil on any particular fabric. An F factor is proposed to give the relative visibility on different fabrics. [ABSTRACT FROM AUTHOR]

The concept of metamerism and its definition is discussed briefly in terms of the spectral reflectance characteristics of colored materials, the spectral power distribution of the illuminant and the color-matching properties of the observer's eyes. Various ways of defining a degree of metamerism are explained and methods outlined that are potentially useful to specify the degree of metamerism. The Colorimetry Committee of the Commission Internationale de l'Eclairage (CIE) is currently studying several methods with the view to arriving at one or more that are suitable for practical applications and can be recommended internationally. [ABSTRACT FROM AUTHOR]

The article reports on the results of research which was conducted in an effort to evaluate a selective colorimetric determination of local anesthetics which contained a tertiary amine. Researchers found that the accuracy of the colorimetric determination was dependent upon complete extraction of the respective tertiary amine anesthetic into a single portion of toluene after the aqueous solution had been made alkaline with ammonia.

A conference paper on a method for quantitative studies on salivary amylase is presented. This method involves incubating starches with a small amount of saliva and using photocolorimetry to study starch-iodine interactions. Human salivary alpha-amylase can then be determined by comparing it with commercial amylase tested in the same way.

A letter to the editor is presented in response to the article about a new chemical syndrome called malvaria.

In an earlier paper (1) the changes in the reflectance spectra of cellulose triacetate samples upon immersion in water were used to deduce an empirical relation between the reflectance of "wet" and "dry" fabrics. From this relationship it follows that upon immersion in water, samples not only become darker, but that color purity increases and in most cases hue also changes. Experimental evidence is presented to substantiate this prediction. [ABSTRACT FROM AUTHOR]