Medium fraction

The checkers eluted the columns with a slight positive air pressure on the solvent reservoir to prevent formation of gas bubbles and cracks in the chromatographic medium. Fractions were collected in 25-mL test tubes (Note 1), analyzed by TLC on silica gel, eluting with the column solvent, and visualized with a phosphomolybdic acid solution. The checkers observed a nonvolatile hydrocarbon material (not substrate related) which was eluted in the fractions just prior to the products, which are quite nonpolar themselves and are eluted in the early fractions, ahead of any unreacted ester. Colored, metal-containing components usually remain near the top of the column, although some colored material may accompany the... 

In a study of ballistic properties of a three-modal composite rocket propellant, the effect of coarse, medium and fine fractions of ammonium perchlorate on burning rate at 70 bar and 25 °C has been mathematically modeled. Limitations were imposed on the ratios of all three granulations of ammonium perchlorate xrfine fraction AP-7 pm=0.3-0.7 x2-coarse fraction AP-400 pm=0.0-0.40 x3-medium fraction AP-200 pm=0.30-0.70. 

Dendrons attached as side chains on linear polymer chains behave different from free dendrimers and dendrons. Block copolymers, poly(3,5-bis(3,5-bis (benzyloxy)benzyloxy)-benzyl methacrylate-random-methacrylic acid)-block-poly(2-perfluorooctylethyl acrylate), possess poly(benzylether) dendrons and perfluorinated alkyl chains in their side chains (Fig. 4) [85], While an LB film of a copolymer with a medium substitution fraction of poly(benzylether) dendron side chain in poly(methacrylic acid) displays flat surface, a copolymer with high fraction of poly(benzylether) dendron side chains produces the zone texture. Dendron rich blocks are hydrophobic and oleophilic but perfluorinated blocks are solvophobic. Therefore, in this case, the solvophobicity-to-solvophilicity balance must be considered. As a result, copolymers with medium fraction of dendron are laid on solid substrate, but dendron blocks of copolymers with high fraction prefer to arrange at air side of air/ water interface and the fluorocarbon blocks are enforced to exist close to water subphase, resulting in the zone texture [86]. These situations of molecular arrangements at air/water interface are kept even after transfer on solid substrate. By contrast, when perfluorooctadecanoic acids are mixed with block copolymers with high dendron fraction, the flat monolayers are visualized as terrace [87], The monolayers are hierarchized into carboxyl, per-fluoroalkyl, and dendron layers, that is, hydrophilic, solvophobic, and oleophilic layers. In this case, perfluorooctadecanoic acids play a role for ordering of block copolymers. 

The foaming tendency of the liquid can affect the value of kLaL. Figure 7 illustrates the behavior of kLaL for CO and H2 in various fractions of F-T liquid (Deimiing et al., 1985). The results indicate that due to the pronounced foaming tendency of a medium fraction of F-T liquid, the effect of temperature on kLaL for this fraction is the reverse of that for light and heavy fractions. 

Antibodies and related molecule to separate Molecular size" (average) Exclusion limit of GF medium Fractionation range b Example of GF medium... 

Experimental studies of the slow flow of highly-concentrated systems were made on polyfractional filler dispersions in glycerol whose viscosity was 1.1 Pas. The parameters of initial filler fractions are listed in Table 1. Of these fractions, mixtures of different composition were made, which served as the disperse phase of the systems being investigated. The composition of mixtures and the concentrations of dispersions are listed in Table 2. The average size of filler particles of coarse and medium fractions was determined by standard sieve analysis and that of fine fraction from its sedimentation rate in media of different viscosity by the instrument Micronphotosizer. ... 

However, the nature of the adsorbent affects the adsorption-pH profiles (9,10,11,12). Although the difference in the Fe content of the sand fractions used in this study is small, the large change in the mobility of both As (III) and As(V) between the fine and medium fractions may be due to the difference in the nature of the sand i.e. due to a higher amount of discrete iron oxides in the coarse fraction (13). 

However, this situation allows us to suppose that X2 is much larger then xi. Indeed, if we suppose that the medium fraction of covered surface is 0.5, and that the ratio of defects in the oxide is in the order of 1%, then the / Xj ratio is in the order of 20. 

The total A-starch is separated as a concentrate, while the gluten obtains its typical structure and is discharged with the B-starch via the medium fraction. The %htweight constituents of flour such as pentosane form the third phase. Following on from fine fiber screening, three-phase nozzle separators perform the task of separating the A-starch and recovering the A-starch left in the B-starch. The A-starch is washed by hydrocyclones. Two-phase decanters ensure that the two starch fractions are dewatered and process water is treated in a clarifier. 

A. Govender, Determination and statistical evaluation ofthe effect of minerals and mineral associations in specific dense medium fractions on ash fusion temperature, M.Sc. dissertation, NWU, Potchefstroom, 2005, 83 pp. 

One of the oldest methods used the difference in solubility of RE-potassium sulfates. The oxide mixture was dissolved in acid and potassium sulfate was added. Double salts of elements in the cerium group. La, Ce, Pr, Nd and Sm, have a low solubility and were precipitated first. The double sulfates of the elements Eu, Gd and Tb are a little more soluble but precipitated as a medium fraction. Elements of the yttrium group, Y, Dy, Ho, Er, Tm, Yb and Lu, remained in solution. 

Now, let us introduce cells from 1 to m in the objective cross section as shown in Fig. 42a. The cross section is scanned by number of prefix beams i n, and the average passage length for cell j was ly (for those cells where beam i does not pass ly = 0). The first medium fraction in cell j expressed by Sj is the main unknown variable. Then the total absorbance lu/h can be written as... 

The grain size composition of the mix is coarse. The typical grain size composition of raw materials for the production of carbon cathode blocks (calcined anthracite, graphite, or coke) consists of three (and rarely four) grain fractions. The coarse fraction is 10-5 mm, the fine fraction is less than 0.075 mm, and the medium fraction is 5-0.5 mm. 

The rate of hydration of cement also depends on the particle size of cement. The effect of SNF on the hydration of Type III cement has been studied.t l Three fractions of cement, viz., 72-30 pm (coarse), 30-4 pm (medium), and 4 pm (fine) were hydrated in the presence of SNF. Heat evolution occurring at different times is compared in Fig. 14. The reference sample exhibits a hump at about 12 hours, but, in the presence of SNF, it is shifted to about 20 hours. The fine fraction evolving the most heat is the least retarding of all the samples. Only minimal heat is evolved by the coarse fraction. The presence of higher amounts of alkali and SO3 in the finer fraction explains why it shows the least retardation. The alkali content in the medium fraction is 0.86% and that in the fine fraction is 1.01%. The SO3 contents in the fine and medium fractions are 12.3 and 2.6% respectively. 

Procedure Benzaldehyde (50 mg), 5 % NaOH (5 ml), and 3% hydrogen peroxide (1 ml) are heated at 70 °C in a 20-ml test tube for 10 min. Additional 3% peroxide (1 ml) is added to the mixture under stirring and the mixture is heated over a water bath at 70 °C for another 10 min. After acidification with sulfuric acid the mixture is extracted twice with 3-ml portions of chloroform, the extract is evaporated, and the crude product purified by sublimation. The medium fraction is used for determination of the melting point, which is 122 °C. 

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