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Population density analysis

Analysis of equation 48 shows that a single sample taken either from inside the crystallizer or from the product stream will allow evaluation of nucleation and growth rates at the system conditions. Figure 12 shows a plot of typical population density data obtained from a crystallizer meeting the stated assumptions. The slope of the plot of such data maybe used to obtain the growth rate, and the product of the intercept and growth rate gives the nucleation rate. [Pg.349]

Classified removal of course material also can be used, as shown in Figure 16. In a crystallizer equipped with idealized classified-product removal, crystals above some size ate removed at a rate Z times the removal rate expected for a perfecdy mixed crystallizer, and crystals smaller than are not removed at all. Larger crystals can be removed selectively through the use of an elutriation leg, hydrocyclones, or screens. Using the analysis of classified-fines removal systems as a guide, it can be shown that the crystal population density within the crystallizer magma is given by the equations... [Pg.352]

The purpose of this analysis was to assess the risk of operating Limerick Station, specifically with regard to its location near a high population density area. These risks were evaluated to determine whether they represent a disproportionately high segment of the total societal risk from postulated nuclear reactor incidents. [Pg.120]

Values of population density T(n,ss) at various degrees of polymerization n are obtained through gel permeation chromatography (GPC) analysis. Experimental... [Pg.378]

Gel Permeation Chromatography. The instrument used for GPC analysis was a Waters Associates Model ALC - 201 gel permeation chromatograph equipped with a R401 differential refractometer. For population density determination, polystyrene powder was dissolved in tetrahydrofuran (THF), 75 mg of polystyrene to SO ml THF. Three y -styragel columns of 10, 10, 10 A were used. Effluent flow rate was set at 2.2 ml/min. Total cumulative molar concentration and population density distribution of polymeric species were obtained from the observed chromatogram using the computer program developed by Timm and Rachow (16). [Pg.382]

A kinetic study for the polymerization of styrene, initiated with n BuLi, was designed to explore the Trommsdorff effect on rate constants of initiation and propagation and polystyryl anion association. Initiator association, initiation rate and propagation rates are essentially independent of solution viscosity, Polystyryl anion association is dependent on media viscosity. Temperature dependency correlates as an Arrhenius relationship. Observations were restricted to viscosities less than 200 centipoise. Population density distribution analysis indicates that rate constants are also independent of degree of polymerization, which is consistent with Flory s principle of equal reactivity. [Pg.392]

The resin system selected to initiate these studies is a step-growth anhydride cured epoxy. The approach to the kinetic analysis is that which is prevalent in the chemical engineering literature on reactor design and analysis. Numerical simulations of oligomeric population density distributions approximate experimental data during the early stages of the cure. Future research will... [Pg.275]

Fenchel T, King G, Blackburn FI (1998) Bacterial biogeochemistry the ecophysiology of mineral cycling. Academic Press, London, UK Francl LJ (1993) Multivariate analysis of selected edaphic factors and their relationship to Heterodera glycines population density. J Nematol 25 270-276 Frostegard A, Tunlid A, Baath E (1993) Phospholipid fatty acid composition, biomass, and activity of microbial comunities from two soil types experimentally exposed to different heavy metals. Appl Environ Microbiol 59 3605-3617... [Pg.340]

Laboratory analysis of site soils should be made to determine the presence and population density of naturally occurring microbes that are capable of degrading the contaminant. At a minimum, these analyses should include plate counts to determine the relative number of microbes of several types, the substrate (food) type that reflects the type of chemicals they are likely to consume, and if toxic substances are present. [Pg.281]

The first moment of the distribution is Pt0T the total, cumulative molar concentration of polymeric material. As the molecular weight of polymeric species increases, branching and crosslinking reactions yield a thermoset resin. Chromatography analysis of epoxy resin extracts confirms the expected population density distribution described by Equation 4, as is shown in Figure 2. Formulations and cure cycles appear in Table II. [Pg.328]

Diamond (1966) has applied a filtering procedure in the refinement of protein structures, in which poorly determined linear combinations are not varied. In charge density analysis, the principal component analysis has been tested in a refinement of theoretical structure factors on diborane, B2H6, with a formalism including both one-center and two-center overlap terms (Jones et al. 1972). Not unexpectedly, it was found that the sum of the populations of the 2s and spherically averaged 2p shells on the boron atoms constitutes a well-determined eigenparameter, while the difference is very poorly determined. Correlation between one- and two-center terms was also evident in the analysis. [Pg.79]

While a kinetic analysis may provide a first approximation to population densities, we clearly need to modify our kinetic descriptions. First, the age distribution of individuals must be considered, at least as juveniles, adults, and aged because the reproduction and death kinetics of living systems depend on the individual s age. For humans and for valves this age distribution might look as shown in Figure 8-21. [Pg.358]

The analysis goes as follows Let V-m> Vcl> and VoUt represent volumetric flow rates of clear liquor fed to the crystallizer, of clear-liquor advance, and of output slurry respectively. The population density function is given by the expression ... [Pg.217]

Nykamp D. Q., Trandrina D. A population density approach that facilitates large-scale modeling of neural networks analysis and an application to orientation tuning. J Comput Neurosci, 2000, 8(1), 19-50. [Pg.370]

Tarter ME, Cooper RC, Freeman WR. 1983. A graphical analysis of the interrelationships among waterborne asbestos, digestive system cancer and population density. Environ Health Perspect 53 79-89. [Pg.334]

Examination of individual parameters provided only a limited and somewhat distorted view of the SAM microcosm response to Jet-A. The univariate data analysis did indeed show that there were some significant responses to the toxicant by individual taxa and chemistry however, the responses were scattered over time and did not present a logical, coherent pattern. Furthermore, the individual responses detected were typified by wild swings in a taxon s population density over time. [Pg.339]

Data analysis methodologies that identify unusual temporal or spatial patterns of illness to identify these patterns, the system must have at least a year of historical data for comparison. The historical data must include models that identify normal temporal (e.g., seasonal) variations as well as changes in population density, hospital market areas and health care referral relationships (11)... [Pg.227]


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See also in sourсe #XX -- [ Pg.96 ]




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