Fastness requirements

In this chapter, it was shown that filterFRET is an easy, intuitive and quantitative alternative to record sensitized emission and FRET efficiency. The major advantages of filterFRET over donor-based FRET detection methods (FLIM) are that it can be carried out with standard wide-held or confocal fluorescence microscopes that are available in most laboratories, and that it yields additional data on the acceptor population. FilterFRET is also fast, requiring just two confocal scans (if need be on a line-by-line basis) which minimizes the risk of artifacts due to, for example, organelle movement in living cells, and acquisition can be optimized for each channel independently. However, quantitative... 

This fastness requirement is of practical significance only for disperse dyes on hydrophobic fibres. Dyes of low fastness are sublimed from the surface of the heated fibre at a rate dependent on the temperature of treatment. The diffusion coefficient of the dye in the dry polymer controls the rate at which loss of dye from the surface by volatilisation is replenished from the interior of the fibre. Dye decomposition during the heat fastness test can be highly significant in determining the overall rating attainable with a given dye structure [185]. 

The light fastness requirements of plastic colorations are met by many organic pigments but are similarly dependent on the ratio of colored pigment to titanium dioxide. The stability of the plastic used should also be taken into consideration here. 

P.R.53 1 may also be used in PUR foam products wherever the fastness requirements, especially regarding water, soap, and solvents, are not too stringent. 

As a class, these pigments are characterized by uncommonly clean and brilliant shades. They provide a number of shades, particularly red and violet ones, that can be duplicated by other organic pigments, but without their brilliance and cleanness. These pigments fail to satisfy more stringent fastness requirements. They are not stable to polar solvents, such as alcohols, ketones, and ethylene glycol. Moreover, they also decompose if exposed to alkali. 

Sedimentation- diffusion Absolute fairly fast Requires 3 separate determinations (diffusion coefficient, sedimentation constant and partial specific volume) <5... 

Liu et al. [27] introduced a new lipoaffinity descriptor to account for the effect of molecular hydrophobicity on BBB penetration. The descriptor was defined based on Kier and Hall s atom-type electrotopological state indices and therefore its evaluation is fast, requires no molecular 3D information, and... 

SPEs offer distinctive advantages over conventional liquid-liquid extractions. They are relatively fast, require small sample size, eliminate emulsification problems, provide the possibility of performing both cleanup and preconcentration of the extract in one analytical step, and offer high precision. Another great advantage of SPEs over liquid-liquid extractions is solvent savings. Unlike liquid-liquid extractions that often require hundreds of milliliters for single or multiple extractions, SPEs require only a few milliliters of solvents for analyte extraction and cleanup. 

Polyester Fiber-Nylon Blends. This fiber blend is used in apparel fabrics as well as in earpels. Disperse dyes dye both fibers, however they possess only marginal fastness properties on nylon. Therefore it is important to select those disperse dyes that dye nylon least under the given circumstances. The nylon is dyed with acid dyes, selected according to the fastness requirements. 

Analytical separation and spectroscopic techniques normally used for petroleum crudes and residues were modified and used to characterize coal liquids, tar sands bitumens, and shale oils. These techniques include solvent extraction, adsorption, ion-exchange, and metal complexing chromatography to provide discrete fractions. The fractions are characterized by various physical and spectroscopic methods such as GLC, MS, NMR, etc. The methods are relatively fast, require only a few grams of sample, provide compound type fractions for detailed characterization, and provide comparative compositional profiles for natural and synthetic fuels. Additional analytical methods are needed in some areas. 

These analysis methods are relatively fast, require only a few grams of sample, provide discrete fractions which can be characterized in as much detail as desired with available techniques, and provide comparative compositional profiles for fuels from various sources, both natural and synthetic. The methods have limitations, as indicated throughout the paper. However, as new procedures are developed to take care of these limitations, they can readily be incorporated. 

Acid Monoazo Dyes. Among the acid monoazo dyes are a number of much used wool dyes that possess no outstanding coloristic properties but that are distinguished by brilliance of shade, very good leveling power, and particularly low cost, while their wash- and lightfastness meet only low to medium requirements. Partly influenced by the introduction of the International Wool Label to label high-quality wool articles, the fastness requirements have risen considerably, and this has necessitated the development and manufacture of particularly fast dyes. 

The main area of application for the acid polyamide dyes of group A is in carpet dyeing, but they are also used in other areas of textile dyeing where the fastness requirements are not too stringent. A few structures are presented below to illustrate the types of azo dyes used C.I. Acid Yellow25, 18835 [6359-85-9] (31), C.I. Acid Red 42, 17070 [6245-60-9] (32), C.I. Acid Red 32, 17065 [6360-10-7] (33). 

The leuco compounds of anthraquinoid dyes have a high affinity for the cellulose fiber and give dyeings that meet the highest fastness requirements in use and processing. 

The two-bath process is applied for deep shades and for stringent fastness requirements. In the first step the PES part is dyed with disperse dyes, followed by reductive intermediate clearing and wool dyeing. However, while dyeing the wool component, disperse dye must always be expected to detach from PES and re tint the wool. 

Although the major part of research on resorcinol dyes was actually completed in the 1930s, an increasing number of patent applications were filed into the 1980s. The more recent work was conducted to enhance the scope of available structures, to optimize synthesizing procedures, and to meet new fastness requirements by minimizing byproducts. 

Hair dyes must meet a number of conditions related to their end use. Color can be assessed by colorimetry [49], The limits of precision are set by the substrate on which the measurement is performed. Studies on test subjects are difficult because of the uneven natural hair color and the background color of the scalp. Tresses are hard to prepare at a constant quality level. Measurements on wool cloth give reproducible results, but for oxidation dyes the shades are not identical to those produced on hair. Colorimetric methods are therefore useful only for comparative measurements on the same object, for example, in lightfastness tests. Because hair must be redyed after four to six weeks due to growth, the fastness required of hair dyes is generally less than that needed for textiles. However, stability is still a problem with many indo dyes (see Section 5.4.3). Some of them... 

Design targets for the application were to have a total system volume < 1 cm3 and to achieve one sample throughput per minute [115]. The reaction time for the Berthelot reaction is about 40 s so that only 20 s are left for all other process steps. This involves the injection of the sample, mixing and an optical absorption measurement. Therefore, mixing has to be fast, requiring only a few seconds. 

Why is an overnight fast required before the lactose tolerance test or the breath hydrogen test is administered ... 

Starch finishes are still used in India. Starch cannot be incorporated into pigment pad-bath formulations since it interferes with the final fastness requirements of pigment dyeings. 

Due to the potential regression in supply and use of disazo directs and vats as well as more strenuous wet fastness requirements, textile firms dyeing cotton-containing fabrics are projected to switch production to reactive dyes in increasing numbers. Reactive dyes are unique in that the dye with the cellulose in cotton or rayon. In the process the material is impregnated with the reactive dye, base is added to the bath to effect the dye/fiber chemical reaction, and the fabric is then carried through an afterscour. Reactive dyes have several severe drawbacks ... 

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