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Solution statistics

The most common states of a pure substance are solid, liquid, or gas (vapor), state property See state function. state symbol A symbol (abbreviation) denoting the state of a species. Examples s (solid) I (liquid) g (gas) aq (aqueous solution), statistical entropy The entropy calculated from statistical thermodynamics S = k In W. statistical thermodynamics The interpretation of the laws of thermodynamics in terms of the behavior of large numbers of atoms and molecules, steady-state approximation The assumption that the net rate of formation of reaction intermediates is 0. Stefan-Boltzmann law The total intensity of radiation emitted by a heated black body is proportional to the fourth power of the absolute temperature, stereoisomers Isomers in which atoms have the same partners arranged differently in space, stereoregular polymer A polymer in which each unit or pair of repeating units has the same relative orientation, steric factor (P) An empirical factor that takes into account the steric requirement of a reaction, steric requirement A constraint on an elementary reaction in which the successful collision of two molecules depends on their relative orientation. [Pg.967]

Fig. 4. A schematic two-dimensional illustration of the idea for an information theory model of hydrophobic hydration. Direct insertion of a solute of substantial size (the larger circle) will be impractical. For smaller solutes (the smaller circles) the situation is tractable a successful insertion is found, for example, in the upper panel on the right. For either the small or the large solute, statistical information can be collected that leads to reasonable but approximate models of the hydration free energy, Eq. (7). An important issue is that the solvent configurations (here, the point sets) are supplied by simulation or X-ray or neutron scattering experiments. Therefore, solvent structural assumptions can be avoided to some degree. The point set for the upper panel is obtained by pseudo-random-number generation so the correct inference would be of a Poisson distribution of points and = kTpv where v is the van der Waals volume of the solute. Quasi-random series were used for the bottom panel so those inferences should be different. See Pratt et al. (1999). Fig. 4. A schematic two-dimensional illustration of the idea for an information theory model of hydrophobic hydration. Direct insertion of a solute of substantial size (the larger circle) will be impractical. For smaller solutes (the smaller circles) the situation is tractable a successful insertion is found, for example, in the upper panel on the right. For either the small or the large solute, statistical information can be collected that leads to reasonable but approximate models of the hydration free energy, Eq. (7). An important issue is that the solvent configurations (here, the point sets) are supplied by simulation or X-ray or neutron scattering experiments. Therefore, solvent structural assumptions can be avoided to some degree. The point set for the upper panel is obtained by pseudo-random-number generation so the correct inference would be of a Poisson distribution of points and = kTpv where v is the van der Waals volume of the solute. Quasi-random series were used for the bottom panel so those inferences should be different. See Pratt et al. (1999).
Machinery now exists to permit, in many cases, very detailed analyses of fibrous structures using the under-appreciated X-ray diffraction data supplied by the polymers themselves. Some of this machinery can be adapted to tackle the problem of providing unique solutions statistical tests can be applied to (least-squares) optimised versions of competing models. However, additional or alternative tests of the creditability of different models should not be ignored. [Pg.26]

The optimal reflux ratio policies together with the switching times and the optimal amount and composition of the recycle obtained by two methods are presented in Table 8.3 and the solution statistics are given in Table 8.4. [Pg.243]

Table 8.4. Solution Statistics Using Two Formulations [Mujtaba, 1989] ... Table 8.4. Solution Statistics Using Two Formulations [Mujtaba, 1989] ...
The minimum batch times for the individual cuts and for the whole multiperiod operation are presented in Table 8.8 together with the optimal amount of recycle and its composition for each cut. The percentage time savings using recycle policies are also shown for the individual cuts and also for the whole operation. Figure 8.18 shows the accumulated distillate and composition profile with and without recycle case for the operation. These also show the optimal reflux ratio profiles. Please see Mujtaba (1989) for the solution statistics for this example problem. [Pg.262]

The osmotic pressure calculation remains simple for all dilute solutions. Statistical mechanics gives the Helmholtz free-energy... [Pg.155]

A standard error may be calculated for purposes of constructing a confidence interval for the odds ratio, but it requires an iterative solution. Statistical software is useful for this purpose. Interested readers will find a wealth of information on the odds ratio in Fleiss et al. (2003). [Pg.137]

Electronics of circuitry to control. potential across I interfaces 1 Electronic e conductor 1 Ionic 1 0 conductor Physical chemistry of solutions Statistical mechanics of particle distribution near interface in field... [Pg.69]

While a quantitative molecular explanation of overcoating in latex polymerization is lacking, a qualitative picture can be synthesized with the aid of the polymer solution statistical mechanics developed by Flory (1953) and the phase separation statistics of Meier (1969, 1970). Let us examine... [Pg.467]

An interesting question, which is closely related to the VPIE, is the deviation of isotopic mixtures from the ideal behavior. Isotopic mixtures, that is, mixtures of isotopic molecules (e.g., benzene and deuterated benzene), have long been considered as textbook examples of ideal solutions statistical theory predicts that mixtures of very similar species, in particular isotopes, will be ideal the only truly ideal solutions would thus involve isotopic species molecules which differ only by isotopic substitution... form ideal solutions except for isotope mixtures, ideal solutions will occur rather rarely we expect binary solutions to have ideal properties when the two components are isotopes of each other. ... [Pg.711]

The foUowing activity coefficients and interaction parameters determined by GLC for solute-statistical copolymers may be found in the literature (a) forty three non-polar and polar solutes on ethylene-vinyl acetate copolymer with 29% weight of vinyl acetate at 150.6 and 160.5°C [105] chloroform, carbon tetrachloride, butyl alcohol, butyl chloride, cyclohexanol, cyclohexane, phenol, chlorobenzene and pentanone-2 on the same copolymer with 18% weight vinyl acetate at 135°0 [102], normal xdkanes (C5, Oj, Og, Ojo), oct-l-ene, chlorinated derivatives, n-butanol, toluene, benzene, methyl-propyl-ketone and n-butyl-cyclohexane on the copolymer mentioned with 40% weight vinyl acetate at 65, 75 and 85°0 [68, 106] (b) n-nonane, benzene, chloroform, methyl-ethyl-ketone and ethanol in methyl methacrylate-butyl methacrylate copolymer with 10% butyl methacrylate [32] (c) hydrocarbons in styrene-alkyl methacrylates copolymers at 140°C [101] (d) the solutes in (b) on butadiene-acrylonitrile copolymer with 34% weight acrylonitrile [68]. [Pg.146]

The amplitude and peak latency of the a- and b-waves and the OPs were expressed as the percentage of the control ERG values during the initial perfusion of the control solution. Statistical analysis of the ERG changes was done with the Student s t -test (paired), with p<0.05 indicating a significant difference. [Pg.86]

Zaharov, M. A. Grid models of multi-component solid solutions statistic thermodynamics and kinetics. Abstract of doctoral thesis. Novgorod State University 2008,36 p. [Pg.76]

Outhwaite, C.W., 1975, Equilibrium theory of electrolyte solutions "Statistical Mechanics Vol. 2", Specialist Periodical Reports, Chemical Society, London. [Pg.141]

The expression SEEM came in use in the early 1980s (Contreras 1980 Baecher and Ingra 1981). Der Kiureghian and Ke (1988) defined SEEM as a finite element method which accounts for uncertainties in the geometry or material properties of a stmcture, as well as the applied loads where the uncertainties are usually spatially distributed over the region of the structure and should be modelled as random or stochastic fields. The distinguishing feature of an SEEM is that it involves the discretization of the random field and the computation of solution statistics. [Pg.3469]

Improve. Here, implementation of creative solutions— ways to do things better, cheaper, and/or faster—that address the problems identified dming the analysis phase takes place. Often, other lean methods such as cellular manufactming, 5S, mistake-proofing, and total productive maintenance are identified as potential solutions. Statistical methods are again used to assess improvement. [Pg.579]


See other pages where Solution statistics is mentioned: [Pg.137]    [Pg.173]    [Pg.215]    [Pg.246]    [Pg.439]    [Pg.235]    [Pg.238]    [Pg.703]    [Pg.98]    [Pg.230]    [Pg.115]    [Pg.119]    [Pg.226]    [Pg.102]    [Pg.35]    [Pg.615]   
See also in sourсe #XX -- [ Pg.231 ]




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