T Turbidity

Abbreviations C, coexistence curve S, static light scattering D, dynamic light scattering T, turbidity N, coherent neutron scattering V, shear viscosity E, electrical conductance I, interfacial phenomena (ellipsometry). d Deuterated 1-octanol. 

Chlorides, Place 10ml of the material in a 30ml test tube. Add 10ml of water and mix. Add 10 drops of coned nitric acid, agitate the mixture, and filter. Add 10 drops of a 3 percent aqueous soln of silver nitrate to the hltrate. No precipitate shall settle out within 30 minutes after the addition of silver nitrate soln. A sli t turbidity will not be cause for rejection... 

I = intensity of transmitted radiation X = thickness of sample T = turbidity of sample... 

STA Stafford, S.G., Ploplis, A.C., and Jacobs, D.T., Turbidity of polystyrene in diethyl malonate in the one-phase region near the critical solution point, Macromolecules, 23, 470, 1990. 

For ethyl alcohol, two volumes of dicycZohexyl are mixed with one volume of the alcohol, a thermometer is introduced, and the mixture heated until it becomes clear. The solution is then slowly cooled, with constant stirring, and the temperature is determined at which the opalescent solution suddenly becomes turbid so that the immersed portion of the mercury thread of the thermometer is no longer clearly visible. This is the C.S.T. The water content may then be evaluated by reference to the following table. 

Ij/Io)sca exp(- Tx) and (lt/Io)net exp[-(e + t)x] for the situations itemized above. The turbidity of a specimen, then, is experimentally equivalent to absorption, except it is a small (t < e), classical effect which is generally ignored in absorption studies. To prevent it from being overshadowed by absorption, we consider nonabsorbing systems for which e = 0. 

As the attenuation of the incident beam per unit path through the solution, the turbidity is larger than the Rayleigh ratio by the factor Ibrr/S, since T is obtained by integrating Rg over a spherical surface. Thus, if Eq. (10.54) is written in terms of Rg rather than r, the proportionality constant H must also be decreased by l6n/3, in which case the constant is represented by the symbol K ... 

The microbial assay is based on the growth of l ctobacillus casei in the natural (72) or modified form. The lactic acid formed is titrated or, preferably, the turbidity measured photometrically. In a more sensitive assay, l euconostoc mesenteroides is employed as the assay organism (73). It is 50 times more sensitive than T. casei for assaying riboflavin and its analogues (0.1 ng/mL vs 20 ng/mL for T. casei). A very useful method for measuring total riboflavin in body fluids and tissues is based on the riboflavin requirement of the proto2oan cHate Tetrahjmenapyriformis which is sensitive and specific for riboflavin. 

A solution of 2,4-dichloro-2,.3-dihydro-1-benzothiepin (0.5 g, 2.16 mmol) in f-BuOH (14 mL) was added in one portion to a solution of f-BuOK (246 mg, 2.20 mmol) in t-BuOH (24 mL). After stirring for 50 min, the turbid orange solution was poured into H20 (150mL) and extracted with CHCl3. The extract was washed with H20 and dried (MgS04). The solvent was removed under reduced pressure to give a yellow oil [yield 330 mg (79%)] which was further purified by chromatography (alumina, petroleum ether). 

This section deals with the experimental determination of the rate of oil solubilization in aqueous solutions of AOS and IOS [70]. The experimental method [71] consists of injecting 25 pi of n-hexadecane (containing 5 wt % Dobanol 45-3 as an emulsifier) into 50 ml water this produces a turbid macroemulsion upon vigorous stirring. At the start of the experiment, a concentrated solution of the surfactant under test is injected and the decrease in turbidity is followed with a photometer. The time elapsed to reach 90% of the initial turbidity is recorded (t ) and the pseudo rate constant of oil solubilization is calculated from... 

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