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Regularities in the Experimental Data

In Ref. 6 a graph is presented containing all experimental results on the onset and completion of turbulence in smooth rod bundles. There appears to be a wide spread in the experimental data, attributed to differences between the test sections with which the data were obtained, notably differences in relative wall distance and number of rods. There is no clear correlation between the onset and completion Reynolds numbers and the relative pitch, despite the curves that are suggested in the graph. For regular square arrays the onset Reynolds numbers range from 200 to 2(XX). The completion of turbulence takes place between Re = 3(X)0 and Re = 10. ... [Pg.364]

The LSQ method finds a solution that gives the best fit to the expraimental data. However, it suffers from the problem that the noise in the experimental data are carried through to the final result. To minimize the noise in the deconvoluted distribution, a maximum entropy method (MEM) can be applied [40], Figure 7.9 shows the isotope deconvolution of the experimental spectrum of a deuterated peptide with both LSQ method and MEM method. While LSQ gives a noisy distribution with some negative abundances, MEM produces a smoother and more realistic distribution of the trimodal isotope distribution. Similar performances were also obtained by a fast Fourier transform method [6] and an LI regularization method [8] with significantly improved computation speed. [Pg.118]

However, the B.E.T. and modificated B.E.T as well as isotherm of d Arcy and Watt fit the experimental data only in some range of the relative humidities up to about 80-85%. At the same time the adsorption in the interval 90-100% is of great interest for in this interval the A— B conformational transition, which is of biological importance, takes place [17], [18]. This disagreement can be the result of the fact that the adsorbed water molecules can form a regular lattice, structure of which depends on the conformation of the NA. To take into account this fact we assume that the water binding constants depend on the conformational variables of the model, i.e ... [Pg.121]

The experimental data show that the magnitude of the heat capacity (or similarly of the specific heat) under adiabatic conditions decreases regularly with the increase of filler content. This phenomenon was explained by the fact that the macromolecules, appertaining to the mesophase layers, are totally or partly excluded to participate in the cooperative process, taking place in the glass-transition zone, due to their interactions with the surfaces of the solid inclusions. [Pg.164]

The contribution of this lack of regularity to the entropy of ice is thus R In 3/2 = 0.805 E. U. The observed entropy discrepancy of ice at low temperatures is 0.87 E. U., obtained by subtracting the entropy difference of ice at very low temperatures and water vapor at standard conditions, for which the value 44.23 E. U. has been calculated from thermal data by Giauque and Ashley,7 from the spectroscopic value 45.101 E. U. for the entropy of water vapor given by Gordon.8 The agreement in the experimental and theoretical entropy values provides strong support of the postulated structure of ice.9... [Pg.799]

Fig. 3.17 Average pressure drop reduction as a function of flow rate for a series of different surfaces in a micro-channel having dimensions W = 2.54 mm, H = 127 pm, and L = 50 mm. The experimental data include a series of ultrahydrophobic surfaces with a regular array of square micro-posts with d = 30 pm with a spacing between micro-posts of w = 15 pm represented by triangles (A), <7 = 30 pm and w = 30 pm represented by squares ( ), J = 30 pm and w = 60 pm represented by circles ( ), and d = 30 pm and w = 150 pm represented by diamonds ( ). Reprinted from Ou et al. (2004) with permission... Fig. 3.17 Average pressure drop reduction as a function of flow rate for a series of different surfaces in a micro-channel having dimensions W = 2.54 mm, H = 127 pm, and L = 50 mm. The experimental data include a series of ultrahydrophobic surfaces with a regular array of square micro-posts with d = 30 pm with a spacing between micro-posts of w = 15 pm represented by triangles (A), <7 = 30 pm and w = 30 pm represented by squares ( ), J = 30 pm and w = 60 pm represented by circles ( ), and d = 30 pm and w = 150 pm represented by diamonds ( ). Reprinted from Ou et al. (2004) with permission...
On experimental level the question regarding the centers of adsorption was addressed in numerous papers. For instance, in [66] the experimental data were used to show that in case of adsorption of hydrogen atoms on the surface of zinc oxide the centers of chemisorption can be provided by regular oxygen ions of the lattice, i.e. the process of chemisorption of H-atoms can be shown as the following sequence of reactions ... [Pg.89]

Central E14-C bonds are longer (about 0.1 A) than the E14-CMe bonds, and the E14-C-E15 angles are greater than the ideal tetrahedral angle of 109.4°, which indicates considerable steric strain due to short nonvalent contacts X---E15. For betaines of the tin series, the E14 E15 distance approaches the sum of van der Waals radii of atoms (Table XI). This regularity is distinctly seen in the experimental X-ray data (see Section 3). [Pg.75]

We find, from the models that fit the experimental data, that A j/kgT is most often in the range from -0.3 to 0. It varies quite regularly with variation of species in a manner that is consistent with the conclusion that the important effects of ion size are explicitly accounted for in Eq. (9). ( 33,3 0 The most striking regularity is that if i and j are both species that are all or largely hydrophobic then A j tends to be nearly... [Pg.554]

Owing to their numerous actual and potential applications, several ternary and complex systems of these metals, especially of aluminium, have been investigated a few examples of the systematics of Al-Me-X alloys are presented in 5.18 and in Fig. 5.41. Recent contributions to this subject have been given with the study of the systems R-Al-Cu (Riani et al. 2005, and references there in). These rare earth alloys, characterized by the formation of several intermediate phases, are interesting also as raw materials for the preparation of amorphous alloys. Regularities in the trends of their properties have been underlined. The experimental and calculated data relevant to the binary systems Al-Fe, Al-Ni and Fe-Ni have been examined and discussed in a paper concerning the assessment of the ternary Al-Fe-Ni system (Eleno et al. 2006). [Pg.486]

In this paper we have presented a new model for determining the pore size distribution of microporous and mesoporous materials. The model has been tested using the adsorption isotherms on pure as well as mixtures of MCM-41 materials. The experimental data of adsorption of nitrogen at 77.4 has been inverted using regularization technique. The results of PSD by the present model are compared with the pore size obtained from other classical methods, NLDFT [16] as well as the that obtained by X-ray diffraction methods. [Pg.609]

An analysis of the RDF for the acid solution shows that the In3+ ion is bonded to six water molecules at 2.17 A (Fig. 28). The same In—H20 distance is found for octahedrally coordinated In3+ in crystal structures (223, 224). According to the difference curve this coordination is not changed by the hydrolysis. A possible model for a tetranuclear complex with four octahedrally coordinated In atoms occupying the four corners of a regular tetrahedron and joined by single hydroxo bridges is shown in Fig. 28. It is consistent with the experimental data and seems to be a likely model for the hydrolysis complexes formed in solution, but has not yet been found in crystal structures. [Pg.220]


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In experimentation

The Data

The Experimental Data

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