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N parameters

It is worthwhile to make an additional point on the polymer-solvent interaction parameter Xi3- In reality it may be a function of the reaction temperature thus, isooctane, being a strong precipitating media for polystyrene at room temperature, may represent a better solvent at 70-80°C. Consequently, the start of phase separation and the resulting porous structure may well depend on the reaction conditions [267]. In the case of acrylic-type copolymers, the influence of temperature on the Flory-Hu ns parameter was found to be even more important [268]. [Pg.85]

On the basis of data obtained the possibility of substrates distribution and their D-values prediction using the regressions which consider the hydrophobicity and stmcture of amines was investigated. The hydrophobicity of amines was estimated by the distribution coefficient value in the water-octanole system (Ig P). The molecular structure of aromatic amines was characterized by the first-order molecular connectivity indexes ( x)- H was shown the independent and cooperative influence of the Ig P and parameters of amines on their distribution. Evidently, this fact demonstrates the host-guest phenomenon which is inherent to the organized media. The obtained in the research data were used for optimization of the conditions of micellar-extraction preconcentrating of metal ions with amines into the NS-rich phase with the following determination by atomic-absorption method. [Pg.276]

The Ns is useful in analyzing a problematic pump and in purchasing a new pump. When the parameters of a new pump are determined, the speed, flow, and head can be worked through the Ns formula to give a value indicating a certain type impeller design. Sec Figure 6-22. [Pg.75]

Typical mass resolution values measured on the LIMA 2A range from 250 to 750 at a mass-to-charge ratio M/ Z= 100. The parameter that appears to have the most influence on the measured mass resolving power is the duration of the ionization event, which may be longer than the duration of the laser pulse (5—10 ns), along with probable time broadening effects associated with the l6-ns time resolution of the transient recorder. ... [Pg.590]

Maximumtotal alkalinity consistentwith acceptable steam purity. If necessary, the limitation on total alkalinity should override conductance as the control parameter. If make-up is demineralized waterat 600-1000 Ib/in g, boiler wateralkalinity and conductance should be shown in the table for the 1001 -1500 Ib/in g range. NS (not specified) in these cases refers to free sodium- or potassium-hydroxide alkalinity. Some small variable amount of total alkalinity will be present, and measurable with the assumed congruent control or volatile treatment employed at these high-pressure ranges. [Pg.359]

The kinetic scheme applicable to the Valinomycin carrier system is given in Fig. 18 where S is the carrier and MS+ is the carrier-cation complex. There are five unknown parameters, the four rate constants and Ns, the interfacial concentration of... [Pg.207]

Cook (Ref 21) presents a thermo-hydrodynamic calcn of the detonation parameters and detonation products of two NS expls containing 25/1.5/73.5 NS/A1/AN-SN dope and 27-5/3/ 69.5 NS/A1/AN-SN dope... [Pg.344]

Let us now turn our attention to an interpretation of Ycr particularly to the question of what numerical values might be appropriate under certain conditions. Based on the discussion above, we would expect to find that values in excess of 10 kg/mol-ns would be appropriate for materials below Tg. What we seek is a method of checking this prediction by calculating an approximate value from molecular parameters. To do this we will consider the repulsive interaction as largely a steric one due to the van der Waals repulsions of a pair of chain elements. To the extent that this picture applies, we can calculate an approximate 7c by expanding the van der Waals pair interaction, energy,... [Pg.112]

For a fixed molar ratio (ns/riAh equal to 0.05887, the temperature as applied in experiment E4, and a batch time of 347.8 dimensionless units, the feed rate of B (and thus the feed time) was optimized by computation to find tj = 323.19 dimensionless units. A run was carried out at these conditions. The data collected from this experiment were then used for re-estimation of the kinetic parameters. The new kinetic model was used to evaluate the new optimum feed rate for the same total amount of B. The optimum batch time reduced to 275.36 and the feed time to 242.75 units. Table 5.4-19 summarizes the results for three successive optimizations and re-estimations. Evidently, even a very simplified kinetic model can be successfully used in search for an optimum provided that kinetic parameters are updated based on every subsequent run carried out at the optimum conditions evaluated from the preceding set of kinetic parameters. [Pg.325]

In this fitting procedure the time-dependent diffusion coefficient as discussed above has been taken explicitly into account. As can be seen, with only two parameters both sets of spectra are well described. This holds also for the other two samples. For the model parameters, the fit reveals Nc = 150 and A (0)/ = 0.18 ns. Nc is very close to Nc = 138 as obtained from the NSE experiments on long-chain PE (see next section). [Pg.33]

Q-dependence of the plateau levels. The results for the model parameters are given in Table 3. The crossover time xe = 15 ns (T = 492 K) calculated with Eq. (41b) agrees well with the observed spectral shape in dividing the initial fast decay from the plateau-like behavior at longer times. Figure 25 (lower part) compares the experimental spectra for times longer than xe with the local... [Pg.48]

Figure 36 is a three dimensional representation of the order parameter P at 350 K after 19.2 ns of simulation, where about 25% of the system has transformed into the crystalline state. The black regions near both side surfaces correspond to the crystalline domains with higher P values, while the white regions are in a completely isotropic state of P = 0. Detailed inspection of these data has shown that no appreciable order is present in the melt. A simple interface model between the crystal and the isotropic melt seems to be more plausible at least in this case of short chain Cioo-... [Pg.76]

Lifetime heterogeneity can be analyzed by fitting the fluorescence decays with appropriate model function (e.g., multiexponential, stretched exponential, and power-like models) [39], This, however, always requires the use of additional fitting parameters and a significantly higher number of photons should be collected to obtain meaningful results. For instance, two lifetime decays with time constants of 2 ns, 4 ns and a fractional contribution of the fast component of 10%, requires about 400,000 photons to be resolved at 5% confidence [33],... [Pg.133]


See other pages where N parameters is mentioned: [Pg.199]    [Pg.131]    [Pg.87]    [Pg.242]    [Pg.13]    [Pg.199]    [Pg.131]    [Pg.87]    [Pg.242]    [Pg.13]    [Pg.1433]    [Pg.296]    [Pg.248]    [Pg.617]    [Pg.175]    [Pg.557]    [Pg.131]    [Pg.637]    [Pg.131]    [Pg.373]    [Pg.98]    [Pg.101]    [Pg.103]    [Pg.54]    [Pg.45]    [Pg.86]    [Pg.159]    [Pg.134]    [Pg.213]    [Pg.406]    [Pg.434]    [Pg.258]    [Pg.298]    [Pg.29]    [Pg.45]    [Pg.63]    [Pg.105]    [Pg.32]    [Pg.354]    [Pg.64]    [Pg.64]    [Pg.660]   
See also in sourсe #XX -- [ Pg.537 ]




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