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Some remarks

Bubble, or Droplet Controlled by Mass or Heat Transfer [Pg.373]

To avoid confusion, in this section we explicitly distinguish concentrations expressed in kg/m, and dimensionless concentration such as weight fraction. The former will be denoted as C, and the latter as w (weight fraction). The relation between C and w is [Pg.375]

There are many subtleties in adopting the reference frame (Brady, 1975a), some of which are discussed here so that the different forms of equations during crystal dissolution or growth and during bubble dissolution or growth can be understood. [Pg.375]

In the case of one-dimensional crystal dissolution with u = Uq, if the reference frame is fixed at the faraway melt (x = oo), the melt does not flow even though the melt is generated at the interface at velocity u. (The interface moves as a rate of u.) Hence, the diffusion equation is Equation 3-9 without a velocity term  [Pg.376]

Still in the case of one-dimensional dissolution, if the reference frame is fixed at the non dissolving part of the crystal x = - oo), the interface moves at a velocity of However, any point in the melt is moving at a velocity of w That is, relative to the reference frame fixed to the nondissolving part of the crystal, the melt flows at a velocity of (w — w ). Hence, the equation to describe diffusion in the melt is the flow-diffusion equation (Equation 3-19b), [Pg.376]

A second effect concerns the overall rate equation. If O and/or R are present in the bulk electrolyte as a complex or a number of complexes, the total concentration cGt of the oxidized species is given by [Pg.290]

The latter formulation is more convenient to account for mass transfer, since in the case that equilibria between the complexes are fast, the diffusion laws have to be applied to their total concentrations. The major consequence for our mathematical expressions is that the quantity exp (f) should be replaced by 1/2 [Pg.290]

In addition, the potential difference that acts on the energy diagram is E — j)x rather than E. Hence, in the exponentials describing kj1, etc., [Pg.291]

In the previous sections we have obtained an expression for the steady state homogeneous gas phase nucleation rate. Two approaches were examined. The first, that of McDonald, yields an anal)dic result in a straightforward way. The second approach, which is less direct, is more suited to numerical solutions to complex nucleation problems. It yields the same result for homogeneous nucleation as obtained with McDonald s approach. We will now examine a few alternative forms of Eq. (13) for the homogeneous gas phase nucleation rate. These forms are often referred to in the literature and it is useful to be familiar with them, even though they will not be discussed in this paper. [Pg.207]

As the critical cluster size is often fairly large, Eq. (13) is sometimes replaced by an integral equation [Pg.207]

This is sometimes referred to as a continuous solution to the nucleation equations. [Pg.207]

As the equilibrium Boltzmann concentration of critical clusters bi is smaller than that of any other cluster size (the free energy is at a maximum at i y Fig. 2) Eq. (13) is often rewritten as [Pg.207]

is expected to vary slowly with i but 6, will depend strongly on i, we can expand Cjhj around /. If we write [Pg.207]


According to some remarks concerning the physical interaction between the incident ultrasonic wavelet and the defects [4-6], we consider that an Ascan signal, may be described as a weighted sum of few delayed and phase-shifted replicas of the ultrasonic incident wavelet j(r). We can express this mathematically as ... [Pg.174]

Franok J and Rabinowitoh E 1934 Some remarks about free radioais and photoohemistry of soiutions Trans. Faraday See. 30 120... [Pg.868]

Heather R and Metiu H 1985 Some remarks concerning the propagation of a Gaussian wave packet trapped in a Morse potential Chem. Phys. Lett. 118 558-63... [Pg.1087]

Franck J and Rabinowitsch E 1934 Some remarks about free radicals and the photochemistry of solutions Trans. Faraday Soc. 30 120-31... [Pg.1618]

Finally, some remarks will be made concerning the monitoring of reactions. [Pg.3]

This section is concluded with some remarks related to a connection between normed spaces. Let V, W be two normed spaces such that V C W, V is dense in W and... [Pg.33]

We omit the proof of the theorem since it is analogous to that of Section 3.3 and restrict ourselves to some remarks. When proving the existence theorem the following estimates are obtained ... [Pg.214]

K. N. Cederquist, Some Remarks on WoodHydrolysyation, Report of a Seminar Held at Eucknow, India, 1952, on Production and Use ofPowerA.lcoholinA.sia andtheParEast, Technical Assistance Administration, United Nations, New York, 1954, pp. 193—198. [Pg.336]

A detailed account of the steps that led to the first transistor, and the steps soon afterwards to improve and miniaturise the device, and to shift from germanium to silicon, would take too much space in this chapter, and the reader must be referred to Riordan and Hoddeson s systematic and rivetting account, though space will be found for a brief account of the subsequent birth of the integrated circuit, the vector of the information age. But before this, some remarks are in order about the crucial interplay of physics and metallurgy in the run-up to the transistor. [Pg.259]

The parameters Ci, t2 were postulated to be dependent only upon the substrate, and d, d2, upon the solvent. A large body of kinetic data, embodying many structural types and leaving groups, was subjected to a statistical analysis. In order to achieve a unique solution, these arbitrary conditions were imposed cj = 3.0 C2 for MeBr Cl = C2 = 1.0 for f-BuCl 3.0 Ci = C2 for PhsCF. Some remarkably successful correlations [calculated vs. experimental log (fc/fco)l were achieved, but the approach appeared to lack physical significance and was not much used. Many years later Peterson et al. - showed a correspondence between Eqs. (8-69) and (8-74) in particular, the very simple result di + d, = T was found. [Pg.434]

A review on this topic was given by Finney in 1979154). As was pointed out by the author, at this time it was likely that at least some deviations of the hydration shell from that in solution would occur because there would probably be some remarkable perturbations of the hydration shell due to the interactions with neighboured molecules. Furthermore, the pH values and the salt concentrations necessary for preparing protein crystals are not identical with those under the usual conditions for native proteins in solution which could give rise to deviations in the hydration shell for crystallized and dissolved proteins. [Pg.28]

Carbonyl condensation reactions are perhaps the most versatile methods available for synthesizing complex molecules. By putting a few fundamental reactions together in the proper sequence, some remarkably useful transformations can be carried out. One such example is the Robinson annulation reaction for tire synthesis of polycyclic molecules. The word annulation comes from the Latin annulus, meaning "ring," so an annulation reaction builds a new ring onto a molecule. [Pg.899]

Some Remarks Concerning the Nature of Charge Carrying Moieties... [Pg.216]

The chapter is organized as follows the second section will discuss the photophysics of conjugated polymer/fullerene composites as a standard model for a charge-generating layer in plastic solar cells. Pristine polymer devices will be discussed in the third section while bilayer and interpenetrating network devices are presented in Sections 4 and 5. Section 6 contains some remarks on large area plastic solar cells and Section 7 conclusions. [Pg.271]

The halogens are a family of elements appearing on the right side of the periodic table, in the column just before the inert gases. The elements in this group—fluorine, chlorine, bromine, iodine, and astatine—show some remarkable similarities and some interesting trends in chemical behavior. The similarities are expected since the... [Pg.352]

Chandrasekhar, S., Astrophys. J. 100, 176, "Some remarks on the negative hydrogen ion and its absorption coefficient."... [Pg.327]

Krisement, O., Phil. Mag. 2, 245, Some remarks about electron correlation. A comparative survey of the theories of Wigner (1934) and of Bohm and Pines by means of modulating factor. [Pg.354]

Ruthenium and osmium form some remarkably stable alkyls and aryls compounds, often in unusually high oxidation states. [Pg.75]

The similar species Ir(PMe3)4 likewise shows tetrahedral distortion from square planar geometry (P-Ir—P 152.6-158.9°). It undergoes some remarkable oxidative addition reactions with species like H2O and H2S (Figure 2.72). [Pg.134]

We conclude this section with some remarks concerning complexvalued random variables. A complex-valued random variable can always be written in the form = r + iff> where T and t are realvalued random variables. This means that all averages involving ... [Pg.144]

We close with some remarks concerning the commutation rules obeyed by the field operators tp(x), and Au(x). As noted in this section, a consistent procedure to obtain these would be to use the equations of motion (11-460) and (11-461), together with the postulated properties of and Ain. The procedure is, however, not without ambiguities because in the equation defining the current operator (a ), the quantity — (e/2)[ (a )y(1, (a )] must be supplemented by a rule for handling the... [Pg.705]

It is well known that the operators so defined possess some remarkable properties ... [Pg.712]

In this chapter, the focus is on how zeohte membranes can be appHed in the field of catalysis and to what extent this is successful. The latter is illustrated by reviewing some commonly studied zeohte membrane applications. Finally, the current hurdles that impede industrial application are discussed and some remarks... [Pg.211]

In addition to the examples discussed above, we add the following other reports on Ni Mossbauer studies where only the reference, the material under study, and some remarks about the study are quoted. [Pg.254]

Macdonald R, Marshall AS, Dawson JB, Hinton RW, Hill PG (2002) Chevkinite-group minerals from salic volcanic rocks of the East African Rift. Mineral Mag 66 287-299 McKenzie D (1989) Some remarks on the movement of small melt fractions in the mantle. Earth Planet Sci Lett 95 53-72... [Pg.122]

Charlier B, Zellmer G (2000) Some remarks on U-Th mineral ages from igneous rocks with prolonged crystallisation histories. Earth Planet Sci Lett 183 457-469 Cherniak DJ, Hanchar JM, Watson EB (1997) Diffusion of tetravalent cations in zircon. Contrib Mineral Petrol 127 383-390... [Pg.170]

McKenzie (1989) Some remarks on the movement of small melt frachons in the manhe. Earth Planet Sci Lett 95 53-72... [Pg.246]


See other pages where Some remarks is mentioned: [Pg.5]    [Pg.852]    [Pg.1295]    [Pg.2570]    [Pg.198]    [Pg.20]    [Pg.98]    [Pg.425]    [Pg.294]    [Pg.14]    [Pg.1]    [Pg.765]    [Pg.674]    [Pg.196]    [Pg.29]    [Pg.74]    [Pg.74]    [Pg.209]    [Pg.14]    [Pg.168]    [Pg.120]    [Pg.627]   


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