Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Diluent effects

LAI QUINN Initiator Diluent Effects on Polymerization of HEMA... [Pg.37]

Hoeve.C.A.J., O Brien,M.K. Specific diluent effects on polymer chain dimensions. [Pg.166]

The reference state dimensions unperturbed dimensions, because of the unknown influence of the presence of crosslinks, possibly specific diluent effects, and perhaps at high swelling even an excluded volume effect. We have pointed out that (r2)0 may depend on the concentration of the diluent. Therefore the reference state is in general not a constant. We have also pointed out that, if (r2)0 contains a molecular expansion term due to an excluded volume effect, the use of the Flory-Huggins free enthalpy of dilution is no longer adequate. A difference between the % parameter in a network and the X parameter of the same polymer material but then in solution, may occur because the presence of crosslinks may modify %. [Pg.43]

As pointed out in Chapter III, Section 1 some specific diluent effects, or even remnants of the excluded volume effect on chain dimensions, may be present in swollen networks. Flory and Hoeve (88, 89) have stated never to have found such effects, but especially Rijke s experiments on highly swollen poly(methyl methacrylates) do point in this direction. Fig. 15 shows the relation between q0 in a series of diluents (Rijke assumed A = 1) and the second virial coefficient of the uncrosslinked polymer in those solvents. Apparently a relation, which could be interpreted as pointing to an excluded volume effect in q0, exists. A criticism which could be raised against Rijke s work lies in the fact that he determined % in a separate osmotic experiment on the polymer solutions. This introduces an uncertainty because % in the network may be different. More fundamentally incorrect is the use of the Flory-Huggins free enthalpy expression because it implies constant segment density in the swollen network. We have seen that this means that the reference dimensions excluded volume effect. [Pg.49]

The use of Eq. (II1-35) implies that the unperturbed dimensions are the same in all diluents, i.e. the absence of specific diluent effects is assumed. [Pg.50]

The basic test apparatus consists of a chamber into which a known concentration of vapor (gas) in air is introduced. After thorough mixing, ignition is attempted with a spark or a hot wire. A series of different concentrations are tested to establish the upper and lower concentration limits for flammability. Although normally run with fuel-air mixtures at ambient conditions, other oxidizing atmospheres, diluent effects and temperature and pressure variations can be studied. [Pg.234]

Organic extractants facilitate the transfer of the metal ions from the aqueous phase to the organic phase in solvent extraction. Based on the nature of the organic extractant, the metal ion, and the diluent, effective separation methods can be devised. Uranium extraction into diethyl ether from nitrate medium by salting out is perhaps one of the first uses of solvent extraction for large-scale actinide processing (9). In this case, ether not only acts as the diluent, it also acts as the extractant, which works according to the solvation mechanism (discussed below). [Pg.68]

Jiang Y., Virkar A.V., 2003. Fuel composition and diluent effect on gas transport and performance of anode-supported SOFCs. Journal of the Electrochemical Society 150(7), A942-A951. [Pg.92]

As mentioned earlier, a simple dilution effect may not be achieved by increasing the solution volume. The increase in flow rate on one side of the dialyzing membrane may effect an increased efficiency of dialysis. In this case, part of the diluent effect would be negated by obtaining a larger proportion of the test material in the recipient stream. On the other hand, increased flow rate might decrease the dialysis efficiency and the result obtained would be out of proportion to the simple dilution to be expected. [Pg.357]

Some of the available data on the neutral donor adduct formation of M(TTA)4 chelates are compared against the neutral donor basicities in Fig. 6. The parallel relationships observed between different metal ions suggest that the adducts involved are, most probably, isostructural. A similar relationship showing the diluent effect is given in Fig. 7 and a comparison between the stabilities of the Th(TTA)4 adducts and Th(IPT)4 adducts is shown in Fig. 8. Such correlations are of much practical value in estimating the stabilities of the neutral donor-metal chelate adducts from the data available for similar systems. [Pg.77]

As far as the general shape of the curves is concerned, the presence of maxima indicates that at low concentrations acid soluble oils interact directly with the alkylation reactions and have a beneficial effect toward product quality while at high concentrations the diluent effect on acid strength outweighs any possible benefits. [Pg.254]

Solubility of Components and Diluent Effects (Matrix Effects). Solubility of the analyte is also very important. Solubility of a particular durg... [Pg.362]

Another injection-related effect that can diminish the separation performance is the diluent effect, also known as solvent mismatch. This occurs when the elution strength of the sample solvent is greater than the starting mobile-phase strength. The retention of the analyte on the stationary phase is less in the small plug of sample solvent than it is in the surrounding bulk... [Pg.805]

The first effective synthesis of CgFgAsFfi employed 02AsF as the oxidizer of C F dissolved in liquid WPg. This solvent not only provided the desirable diluent effect for this hot reaction but its relatively high heat capacity also aided in preservation of a lower temperature. These are essential requirements for high-yield syntheses of C5F(AsF and its monocyclic relatives, since all are thermally unstable at ordinary temperatures. In more recent work sulfuryl chloride fluoride has been used as the diluent and moderator and the low working temperatures have resulted in greatly improved yields. Nevertheless, even with SO2CIF, pyrolysis products from the salts are always observed and a quantitative yield has never been obtained for any of the monocyclic cation salts. For these and other reasons the salt composition in each Case has been determined from the stoichiometry of the salt pyrolysis products and other reaction stoichiometries. [Pg.20]

Diluent Effect in the Permeation of through an SLM Containing DMDBTDMA in /i-dodecane as the Carrier... [Pg.901]

Marcus, Y., Diluent effects in solvent extraction. Solv. Extr. Ion Exch., 1989, 7 567-575. [Pg.914]


See other pages where Diluent effects is mentioned: [Pg.334]    [Pg.315]    [Pg.489]    [Pg.41]    [Pg.327]    [Pg.760]    [Pg.40]    [Pg.98]    [Pg.177]    [Pg.35]    [Pg.77]    [Pg.78]    [Pg.79]    [Pg.80]    [Pg.365]    [Pg.177]    [Pg.57]    [Pg.315]    [Pg.760]    [Pg.776]    [Pg.382]   
See also in sourсe #XX -- [ Pg.362 , Pg.363 , Pg.364 , Pg.365 , Pg.366 , Pg.805 ]

See also in sourсe #XX -- [ Pg.221 ]




SEARCH



Americium diluent effects, extraction

Diluent effects, extraction

Diluents

Effect of Diluents on Tg

Effect of diluents

Effects of Counits and Diluents

Flammability limits diluent effect

Inert diluent, effect

Tablet diluents compression speed effect

© 2024 chempedia.info