Critical dyeing rate

Critical Micelle Concentration. The rate at which the properties of surfactant solutions vary with concentration changes at the concentration where micelle formation starts. Surface and interfacial tension, equivalent conductance (50), dye solubilization (51), iodine solubilization (52), and refractive index (53) are properties commonly used as the basis for methods of CMC determination. 

Tracer materials are defined as any product included in the test substance that can be recovered analytically for determining the drift from the application. This may be the active ingredient in an actual tank mix, or it may be a material added to the tank mix for subsequent detection. The selection of an appropriate tracer for assessing deposition rates in the field is critical to the success of a field study. Tracer materials such as low-level active ingredient products, colored dyes, fluorescent dyes, metallic salts, rare earth elements and radioactive isotopes have been used with varying degrees of success in the field. An appropriate tracer should have the following characteristics ... 

The morphological structure of the fiber determines the pathway that dyes take during dyeing and is critical for the rate and extent of dye uptake. In some way, the dye has to penetrate the more or less hydrophobic layer on the fiber surface, formed by the epicuticle and the exocuticle. The strong swelling capacity of the intercellular cement is important for the penetration of dyes into the fiber. Only then are the sulfur-rich keratins also penetrated by the dye molecules. In general terms, Fick s law can be applied to the diffusion phenomena [46],... 

The biodistribution of plasmid can be determined by measuring the rate of disappearance of radiolabeled DNA from the bloodstream and its accumulation in tissues or by the use of fluorescence microscopy to trace the leakage of dye-labeled plasmids from the vasculature. Pharmacokinetic analysis of in vivo disposition profiles of radiolabeled plasmid provides useful information on the overall distribution characteristics of systemically administered plasmids, with one critical limitation. The radiolabel represents both intact plasmid and its metabolites. The plasma half-life of plasmid is less than 10 min, and hence tissue distribution and pharmacokinetic parameters of plasmid calculated on the basis of total radioactivity are not valid at longer time points. Thus, polymerase chain reaction and Southern-blot analysis are required to establish the time at which the radiolabel is no longer an index of plasmid distribution. 

In the case of 7-diethylamino-4-(trifluoromethyl)coumarin ( coumarin-35 ), which has an amino group that is free to rotate, another competitive solvent-dependent decay path has been proposed rotation of the amino group of the planar ICT excited-state molecule can lead to a twisted intramolecular charge-iransfer (TICT) excited-state molecule, from which a radiationless decay to the ground-state molecule occurs [341], Solvent-dependent rate constants for both the radiative and nonradiative decay of excited-state coumarin dyes have been determined [341]. For critical discussions concerning the electronic structure of the excited states of 7-(dialkylamino)coumarins and 7-aminocoumarin ( coumarin-151 ), see references [341d, 341e]. 

CINLEVEL PAN gives a unique strike rate with mild retardation of dyes at the critical temp, range of 180 to the boil thereby eliminating costly hold times below the boiling temperature. 

These occurences were first observed by Osborne Reynolds (1842-1912), when he added a dye to the flow along the axis of a glass tube. In laminar flow a thin thread of colour forms in the axis of the tube, which, due to the low rate of molecular diffusion, hardly gets wider. Increasing the velocity so that the critical Reynolds number is sufficiently surpassed, means that the thread is rapidly mixed up into the flow. In tube flow it can be shown that at Reynolds numbers... 

The rate of adsorption of acid dyes is influenced to a great extent by temperature. There is practically no transfer to the fibre with any of them below 39 C (102°F). From this temperature upwards the rate of adsorption increases, but each dye has its own range over which adsorption is at its maximum. In the case of the acid milling d) es there is, as a rule, practically no dyeing below 60 C (140°F), but there is often a critical period at about 70°C (158°F), where the transfer from dye liquor to the fibre is extremely rapid. It is important, in bulk dyeing, that particular care should be taken to ensure that the rate of rise of temperature is slow over the critical phase. 

Judging from the colour removal efficiencies indicated in Table 14, the solubility of the dye molecules was the dominant parameter for the photodecomposition. Anthraquinone dyes were UV intact due to their chemical structure (Leaver I.H., 1980). Nevertheless, the results from samples 3 to 6 suggested that the solubility was another critical factor to hinder their UV decomposition. The sulphonate anthraquinone reactive dye (sample 6 in figure 8), for example, had a much greater colour removal rate in the experiment (36.8%)... 

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