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Analysis of the Solution

First we estimate the values of the coefficients a, ft, c and r/ for realistic physical values of the characteristic parameters (Table 11.1). [Pg.450]

Taking into account the data in Table 11.1 it is possible to simplify significantly the expressions for the coefficients a, and d.  [Pg.450]

For the study of flow stability in a heated capillary tube it is expedient to present the parameters P and q as a function of the Peclet number defined as Pe = (uLd) /ocl. We notice that the Peclet number in capillary flow, which results from liquid evaporation, is an unknown parameter, and is determined by solving the stationary problem (Yarin et al. 2002). Employing the Peclet number as a generalized parameter of the problem allows one to estimate the effect of physical properties of phases, micro-channel geometry, as well as wall heat flux, on the characteristics of the flow, in particular, its stability. [Pg.450]

The form of the solution of the dispersion equation (11.61) depends on the sign of the determinant D = q + Pl, i.e., on the values of the characteristic parameters g and P. The latter are determined by the physical properties of the liquid and its vapor, as well as the values of the Peclet number. This allows us to use g and P as some general characteristics of the problem considered here. [Pg.451]

The dependence of P (PeL) and g (PeL) is shown in Fig. 11.4. The parameter P (PeL) is a parabola with an axis of symmetry left of the line Pcl = 0. Since the Peclet number is positive, for any value of the operating parameters, the physical meaning is that only for the right branch of this parabola, which intersects the axis of the abscissa at some critical value of Peclet number, Pcl = Peer- The vertical line PeL = Peer subdivides the parametrical plane P - Pcl into two domains, corresponding to positive (PeL Peer) or negative (PeL Peer) values of the parameter P . The critical Peclet number is [Pg.451]


Determination of benzene in air samples has been achieved by bubbling contaminated air through various solvents, followed by uv or in analysis of the solution (90). Methods for identifying benzene in soil, water, and biological media are further described in references 84 and 85. [Pg.46]

Specifics on the type of biological attack. This must be done by some other method such as chemical analysis of the solution (plus consideration given to limitations to the use of these several electrochemical techniques for MIC studies, noted previously under Corrosion Testing Laboratoiy Tests and subsequent subsections). [Pg.2441]

The reaction of magnesium metal with aqueous strong acid, which appears in Figure 4-12. illustrates the fundamental principles of oxidation-reduction. When a piece of magnesium is dropped into a solution of hydrochloric acid, a reaction starts almost Immediately. The metal dissolves, and gas bubbles from the solution. The gas is H2, and analysis of the solution reveals the presence of ions. A list of chemical species before and after the reaction... [Pg.248]

To support the analysis of the solutions we will introduce several new predicate types. We have already described the basic state model in Section II, E. Explicitly manipulating parts of this model is an important component of the reasoning required to derive new control conditions. We will introduce the predicate, form , which will enable us to analyze the form of the state update rules, or constraints between variables. Thus, for our flowshop example we have two basic types of constraints ... [Pg.310]

The starting step of the present work is a specific analysis of the solution of the Schrodinger equation for atoms (section 1). The successive steps for the application of this analysis to molecules are presented in the section 2 (description of the optimised orbitals near of the nuclei), 3 (description of the orbitals outside the molecule), and 4 (numerical test in the case of H ). The study of other molecules will be presented elsewhere. [Pg.19]

Such a distinction in composition inhomogeneity of the copolymers may have caused the variation in transparency which was observed experimentally by Sloco-mbe [36]. He examined forty-four three-component systems and established several empirical rules enabling the interpretation of experimental data on the transparency of high-conversion terpolymers. These empirical rules were explained later [37] in terms of the theory of dynamic systems whose methods have been successfully employed for qualitative analysis of the solutions of the set of dynamic... [Pg.179]

Halmann reported in 1978 the first example of the reduction of carbon dioxide at a p-GaP electrode in an aqueous solution (0.05 M phosphate buffer, pH 6.8).95 At -1.0 V versus SCE, the initial photocurrent under C02 was 6 mA/ cm2, decreasing to 1 mA/cm2 after 24 h, while the dark current was 0.1 mA/cm2. In contrast to the electrochemical reduction of C02 on metal electrodes, formic acid, which is a main product at metal electrodes, was further reduced to formaldehyde and methanol at an illuminated p-GaP. Analysis of the solution after photoassisted electrolysis for 18 and 90 h showed that the products were 1.2 x 10-2 and 5 x 10 2 M formic acid, 3.2 x 10 4 and 2.8 x 10-4 M formaldehyde, and 1.1 x 10-4 and 8.1xlO 4M methanol, respectively. The maximum optical conversion efficiency calculated from Eq. (23) for production of formaldehyde and methanol (assuming 100% current efficiency) was 5.6 and 3.6%, respectively, where the bias voltage against a carbon anode was -0.8 to -0.9 V and 365-nm monochromatic light was used. In a later publication,4 these values were given as ca. 1% or less, where actual current efficiencies were taken into account [Eq. (24)]. [Pg.349]

Valand and Heusler29 determined jAX3+ experimentally, by chemical analysis of the solution. Hence, the oxygen ion current could also be estimated from the total current and jA] +. [Pg.413]

By studying the changes in pH during reaction, and by following species from infrared analysis of the solution, Scheme 7 was proposed for the mechanism, using Fe carbonyl as the catalyst ... [Pg.126]

Chemical/Physical. 1,2,4,5-Tetrabromobenzene (150 mg in 250-mL distilled water) was stirred in the dark for 1 day. GC analysis of the solution showed 1,2,4-tribromobenzene as a major transformation product (Kim and Saleh, 1990). [Pg.1018]

If a salt undergo hydrolysis in solution according to the equation M--t-X + H O M-+ OH -P X + H, and the adsorbing agent selectively adsorbs the acid H X the hydrolysis will evidently proceed further until equilibrium is attained. In the case of Fuller s earth it may be considered that the earth selectively adsorbs hydrochloric acid leaving an alkaline solution of caustic soda. This view of promoted hydrolysis by adsorption is at variance with the hypothesis of ionic interchange and can only be tested by careful analysis of the solution to find out whether ionic interchange has taken place or no. [Pg.187]

Accuracy. Sample solutions of known concentration (e.g., spiked placebo) are used for the accuracy determination. Experimental work may be organized so that the same stock solutions are used to prepare both linearity and accuracy solutions. The accuracy solution must be exposed to normal test conditions (e.g., mixing in a heated dissolution vessel). Determine any bias that is caused by the sampling and analysis of the solutions. If a dissolution profile of the drug product is required, accuracy determinations at different concentrations of the required profile will need to be performed (e.g., at 40, 75, and 110% of theoretical release). The results are reported as percent theory. [Pg.61]

The properties of molecules and of intermolecular interactions may be understood by analysis of the solutions of the electronic Schrodinger equation ... [Pg.218]

Oxidation of Bis (l-methyl-2-acetoxypropyl) selenide in the Presence of 2-Methyl-2-butene. The analysis of the solution near the beginning of the reaction showed that 3-acetoxy-l-butene was the only initial product of the oxidation, but after adding 0.5 mole of peracetic acid per mole of selenide, increasing amounts of the oxidation products of 2-methyl-2-butene, such as 2-methyl-3-acetoxy-l-butene, and 3-methyl-3-acetoxy-l-butene were detected. After adding 4 moles of peracetic acid per mole of selenide, the allylic products from the oxidation of 2-methyl-... [Pg.347]

As said above, only a summary of the many reported studies can be given here, and for details the reader is referred to the reviews (49-53) and the papers of the groups mentioned in Section III, B (55). A complete conformational NMR analysis of the solution structure of the adduct with a dinucleotide, i.e. cis-Pt(NH3)2 d(GpG)-N7(l),N7(2) ], has been available for some time (50b). The main features of this structure can be summarized as follows ... [Pg.185]

If the aim is to determine the stability limit of the trickling flow (that is, the limit of existence of a truly stationary flow), one may neglect the effective viscosity terms in Eqn. (5.2-9) and Eqn. (5.2-10). Furthermore, in trickling flow, all derivatives with respect to time or height (z) are equal to zero a stability analysis of the solution of the system of equations against small variations of t or z yields an algebraic equation which permits to calculation of the limit of liquid mass-flow-rate for a given gas flow rate. [Pg.269]

After similar irradiation of a mixture of 20 and ethanol in a mixed matrix of 3-MP and isopentane (4 1) at 77 K, GC-MS analysis of the solution showed the formation of the expected ethanol adduct of the disilene. The regiochemistry of the product will be discussed in the next section. [Pg.832]


See other pages where Analysis of the Solution is mentioned: [Pg.395]    [Pg.402]    [Pg.450]    [Pg.252]    [Pg.297]    [Pg.174]    [Pg.174]    [Pg.180]    [Pg.347]    [Pg.274]    [Pg.217]    [Pg.909]    [Pg.281]    [Pg.238]    [Pg.110]    [Pg.21]    [Pg.821]    [Pg.199]    [Pg.202]    [Pg.215]    [Pg.395]    [Pg.66]    [Pg.315]    [Pg.21]    [Pg.215]    [Pg.37]    [Pg.10]    [Pg.624]    [Pg.240]    [Pg.199]   


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Analysis of solutions

Solutions analysis

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