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Effect of system size

Note that equation (1.19) has been established assuming the line energy r to be a constant. However it was argued (Marmur 1997) that since this quantity results from the atomic or molecular interactions between the three phases in the vicinity of the triple line, it cannot be independent of the contact angle since the relative inclination of the phases affects the extent of these interactions. Calculations of x [Pg.11]

Until now the L/V surface in the vicinity of TL assumed to have a negligible curvature. Hereafter, this assumption will be removed by minimizing the free energy of the whole S/L/V system in the gravitational field, rather than the free energy of the region of radius r around TL. In this case, the curvature at each point Q of the L/V surface has to satisfy the equation of Laplace (1805) (see Appendix A)  [Pg.12]

The minima of these curves correspond to the equilibrium contact angle of the system. [Pg.15]


Figure 4.45. Aplotof n) C/P)/ n) C) versus log W for reaction pairs interacting via the attractive ion-ion potential. Displayed is the effect of system size on the reaction efficiency the total number of surface sites for the 5-cube, the 7-cube, and the 9-cube is N = 98, N = 218, and N 386, respectively. In each case, u = 4 and surface-only correlations are considered. Figure 4.45. Aplotof n) C/P)/ n) C) versus log W for reaction pairs interacting via the attractive ion-ion potential. Displayed is the effect of system size on the reaction efficiency the total number of surface sites for the 5-cube, the 7-cube, and the 9-cube is N = 98, N = 218, and N 386, respectively. In each case, u = 4 and surface-only correlations are considered.
These assumptions may be inadequate for many engineering situations of contemporary interest however, this does not mean that the thermodynamic laws are invalid or that the basic methodology must be modified. For example, all of the operations in Chapter 3 remain valid, but the specifics wiU need to be adapted to treat complex cases. In particular, extensions must be made to include the effects of system size, additional work modes and their variables, and effects of molecular configuration, especially as density and composition change. [Pg.588]

In short, the thermodynamic information of a system, even at equilibrium, is neither static nor uniform. The principle to illuminate would be the time-dependence, and the related effects of system size and composition. The results would be not simply and Mlxy v, but rather /x v(0, and MIj Y< y(t). To arrive at... [Pg.215]

Structure is consistently higher than the random distribution in silica glass due to europium ion clustering but the probability is consistently lower than the random distribution in sodium silicate glasses. This is a classic example showing the effect of system size on simulated glass properties. [Pg.167]

The systems of interest in chemical technology are usually comprised of fluids not appreciably influenced by surface, gravitational, electrical, or magnetic effects. For such homogeneous fluids, molar or specific volume, V, is observed to be a function of temperature, T, pressure, P, and composition. This observation leads to the basic postulate that macroscopic properties of homogeneous PPIT systems at internal equiUbrium can be expressed as functions of temperature, pressure, and composition only. Thus the internal energy and the entropy are functions of temperature, pressure, and composition. These molar or unit mass properties, represented by the symbols U, and S, are independent of system size and are intensive. Total system properties, J and S do depend on system size and are extensive. Thus, if the system contains n moles of fluid, = nAf, where Af is a molar property. Temperature... [Pg.486]

Perforations are usually 0.32 to 0.64 cm Vh to Vi in) in diameter, set 1.27 to 1.81 cm to Vi in) apart, on square or triangular pitch. There appears to be relatively httle effect of hole size on extraction rate, except that with systems of high interfacial tension smaller holes will... [Pg.1479]

Note that this method enables one to observe variation of electric conductivity of a sample due to adsorption of hydrogen atoms appearing as a result of the spillover effect, no more. In a S3rstem based on this effect it is rather difficult to estimate the flux intensity of active particles between the two phases (an activator and a carrier). The intensity value obtained from such an experiment is always somewhat lower due to the interference of two opposite processes in such a sample, namely, birth of active particles on an activator and their recombination. When using such a complicated system as a semiconductor sensor of molecular hydrogen (in the case under consideration), one should properly choose both the carrier and the activator, and take care of optimal coverage of the carrier surface with metal globules and effect of their size [36]. [Pg.245]

This review will restrict itself to boron-carbon multiple bonding in carbon-rich systems, as encountered in organic chemistry, and leave the clusters of carboranes rich in boron to the proper purview of the inorganic chemist. Insofar as such three-dimensional clusters are considered at all in these review, interest will focus on the carbon-rich carboranes and the effect of ring size and substituents, both on boron and carbon, in determining the point of equilibrium between the cyclic organoborane and the isomeric carborane cluster. A typical significant example would be the potential interconversion of the l,4-dibora-2,5-cyclohexadiene system (7) and the 2,3,4,5-tetracarbahexaborane(6) system (8) as a function of substituents R (Eq. 2). [Pg.357]

Alex CCT, Goh NN, Chia LS (1995) Effects of particle size morphology on ultrasound induced cavitational mechanism in heterogeneous systems. J Chem Soc Chem Commun 2 201-201... [Pg.270]

The effect of crystal size of these zeolites on the resulted toluene conversion can be ruled out as the crystal sizes are rather comparable, which is particularly valid for ZSM-5 vs. SSZ-35 and Beta vs. SSZ-33. The concentrations of aluminum in the framework of ZSM-5 and SSZ-35 are comparable, Si/Al = 37.5 and 39, respectively. However, the differences in toluene conversion after 15 min of time-on-stream (T-O-S) are considerable being 25 and 48.5 %, respectively. On the other hand, SSZ-35 exhibits a substantially higher concentration of strong Lewis acid sites, which can promote a higher rate of the disproportionation reaction. Two mechanisms of xylene isomerization were proposed on the literature [8] and especially the bimolecular one involving the formation of biphenyl methane intermediate was considered to operate in ZSM-5 zeolites. Molecular modeling provided the evidence that the bimolecular transition state of toluene disproportionation reaction fits in the channel intersections of ZSM-5. With respect to that formation of this transition state should be severely limited in one-dimensional (1-D) channel system of medium pore zeolites. This is in contrast to the results obtained as SSZ-35 with 1-D channels system exhibits a substantially higher... [Pg.275]

The effect of particle size, and hence dispersion, on the coloring properties of aluminum lake dyes has been studied through quantitative measurement of color in compressed formulations [47], It was found that reduction in the particle size for the input lake material resulted in an increase in color strength, and that particles of submicron size contributed greatly to the observed effects. Analysis of the formulations using the parameters of the 1931 CIE system could only lead to a qualitative estimation of the effects, but use of the 1976 CIEL m v system provided a superior evaluation of the trends. With the latter system, the effects of dispersion on hue, chroma, lightness, and total color differences were quantitatively related to human visual perception. [Pg.54]

The above demonstration that in a great many cationic polymerisation systems ion-pairs are of no importance as far as the rate of reaction is concerned, raises the question of how it can be explained that in many such systems the nature of the initiator, which determines essentially the nature of the anion, can influence the DP of the polymer formed. In principle, a change of anion, say from a smaller one, e.g., BF4, to a larger one, such as SbF6 could influence the DP in a number of ways. Flowever, probably the most important way is through the effect of ion-size on KD [equation (i)]. [Pg.440]

Effects of particle size and pressure on the reactive sintering were studied by Gobran et al. (2004). The synthesis of RuAl was described it was observed that reactive systems containing low-melting constituents such as aluminium are assisted in densification by the formation of a transient liquid phase. Reactive sintering using... [Pg.571]

Sapsford etal. (2001) examined microarray-based antibody-antigen binding kinetics in real time to determine the effect of spot size. Capture antibodies were immobilized in an array pattern onto silver-clad microscope slides. Antimouse IgG was directly attached to the surface or attached via neutravidin capture of the biotinylated antibody. Cy5-labeled mouse IgG capture was monitored based upon the signal generated from the excitation of an evanescent wave guide (slide) with a 635-nm laser source detection was achieved by a charge-coupled device (CCD) camera system. Both static and flow-through conditions were employed. [Pg.195]


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Effect of size

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