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Transition area

Internal-pressure design rules and formulas are given for cylindrical and spherical shells and for ellipsoidal, torispherical (often called ASME heads), hemispherical, and conical heads. The formulas given assume membrane-stress failure, although the rules for heads include consideration for buckling failure in the transition area from cylinder to head (knuckle area). [Pg.1024]

In this paper we present results from independent studies on the stage 2 to stage 1 transition area that show some unexpected features (anomalies). The results are obtained by electrochemical impedance spectroscopy (EIS), entropy measurements (AS(x)) and in situ x-ray diffractometry (XRD). The aim is to understand the mechanism of stage transition dealing with the observed anomalies. [Pg.262]

The data from the WS model in some cases deviated slightly from the full-bed models. This could be explained by the slightly different layout of the WS model. Some spheres had to be relocated in the WS model to create a two-layer periodicity from the six-layer periodicity in the full-bed models. The differences in velocity magnitudes were mainly found in the transition area between the wall layers and the center layers. The effect of slightly larger gaps between spheres from the nine-sphere wall layers and the three-sphere central layers, due to the sphere relocations, had a noticeable effect on the velocity profile. Differences were also found in the central layer area where the sphere positions were not identical. [Pg.347]

Figure 2. The dependences of gravitational mass M on central pressure Pc for the sets of EoS with variants HEA(a), Bonn(b) and BJ — V(c). Solid lines correspond to the models of neutron stars without a quark core (the variant of nucleon component is indicated). On an enlarged scale the phase transition area is shown for EoS 3a. Figure 2. The dependences of gravitational mass M on central pressure Pc for the sets of EoS with variants HEA(a), Bonn(b) and BJ — V(c). Solid lines correspond to the models of neutron stars without a quark core (the variant of nucleon component is indicated). On an enlarged scale the phase transition area is shown for EoS 3a.
Figure 3. Mass M versus radius R. On an enlarged scale the new additional local mass maximum is shown for neutron stars with a strange quark core. In the upper left corner of Fig. 3b, the phase transition area is shown for the whole set of EoS. Figure 3. Mass M versus radius R. On an enlarged scale the new additional local mass maximum is shown for neutron stars with a strange quark core. In the upper left corner of Fig. 3b, the phase transition area is shown for the whole set of EoS.
Both sepiolite and palygorskite contain tetrahedral silicate sheets (with a variety of substitutions for the Si " ), but the apicies of the tetrahedra are thought to point up or down with the transition areas containing Ca and Mg ions, and bound or associated H2O. The arrangement produces a continuous basal oxygen plane that is compartmentalized. Laths or ribbons three chains wide in sepiolite and two chains wide in palygorskite are separated by discontinuous octahedral areas (Fig. 2.16A and B). [Pg.66]

The complete Knudsen equation (1.26) will have to be used in the transitional area 10 2 < d p < 6 10 mbar cm. Conductance values for straight pipes of standard nominal diameters are shown in Figure 9.5 (laminar flow) and Figure 9.6 (molecular flow) in Chapter 9. Additional nomograms for conductance determination will also be found in Chapter 9 (Figures 9.8 and 9.9). [Pg.17]

For photocycloaddition, to benzene the following conclusions were drawn from this empirical correlation [124], Olefins with poor electron-donor or poor electron-acceptor abilities yield mainly meta adducts with benzene (i.e., if AG > 1.4-1.6 eV, all other olefins yield mainly ortho adducts). Even ethene, which had seemed to behave exceptionally, fits into this correlation provided that it acts as the acceptor. The transition area from ortho to meta cycloaddition (i.e., the AG region where ortho meta = 1 1) is relatively large ( 0.2 eV). This is considered not to be surprising because the AG correlation is based on many different types of olefins. When only AG values for derivatives of 1,3-dioxole and for 1,4-dioxene were used, the transition area was narrowed to 0.03 eV. Not only ethene but also vinylene carbonate now fit into the correlation. According to the ionization potential rule, this compound should give only ortho photocycloaddition with benzene. Mattay s empirical rule predicts mainly meta addition, which is indeed found experimentally. [Pg.99]

Figure 7 demonstrates on a logarithmic scale the dependence of perimeter P on area A of the pores obtained from the binary TEM image of CAS30 in Figure 6b. The (log P - log A) plots obtained from the carbon specimen displayed two straight lines with different slopes that can be divided into region I and II, indicating multifractal geometiy of the carbon specimen. The individual surface fractal dimensions in regions I and II were determined from Eqs. (26) and (27) to be 2.08 + 0.018 and 2.72 + 0.046, respectively. The transition area Ab from region I to II were determined to be 108 nm2, which corresponds to the pore diameter of 12 nm based upon spherical pore shape. Figure 7 demonstrates on a logarithmic scale the dependence of perimeter P on area A of the pores obtained from the binary TEM image of CAS30 in Figure 6b. The (log P - log A) plots obtained from the carbon specimen displayed two straight lines with different slopes that can be divided into region I and II, indicating multifractal geometiy of the carbon specimen. The individual surface fractal dimensions in regions I and II were determined from Eqs. (26) and (27) to be 2.08 + 0.018 and 2.72 + 0.046, respectively. The transition area Ab from region I to II were determined to be 108 nm2, which corresponds to the pore diameter of 12 nm based upon spherical pore shape.
In order to carry this concept of fluidfoil impellers at a uniform velocity of discharge further, the A312 Impeller (Fig. 4) was developed and is used primarily in paper pulp suspensions. Carrying it further is the A320 Impeller (Fig. 5). The A320 has been studied particularly in the transitional area of traditional Reynolds numbers. This is shown in Fig. 6. This figure shows its performance and Reynolds numbers between 10 and 1,000. [Pg.282]

Taking, for instance, Al, with a melting point of 660 °C and a web substrate temperature of 50 °C, zone I formations will be created (porous structure, pointed crystallites, large voids) and up to 250 °C, formations in the transitional area (densely packed fibers) will appear. Up to 450 °C zone II (pillar-shaped crystallites), and above this temperature zone III (conglomerate-type crystallites) formations will be seen. Because of the relatively low maximum thermal stress that may be applied to polymer webs, the growth in metallized layers on polymer webs mainly occurs in Zone I or in the transitional zone. The different growth is also evident from comparison of cooling drum and free-span coater methods. [Pg.192]

Molecules in the transition area of molecular weight (2000-4000 Da depending on molecular shape, rigidity, and solvent viscosity) show little or no NOE. For these molecules an alternative experiment called ROES Y (rotating-frame Overhauser effect spectroscopy, Chapters 8 and 10) is effective. [Pg.199]

Theoretical and computational methodologies are treated in detail elsewhere in this book. Experimental techniques for studying isolated molecules rely on their observation in the gas phase, where molecules can be studied free of interactions. This is different from single molecule studies in which molecules can interact with their environment, but are studied one by one [2], In the gas phase one may study a large ensemble of molecules or clusters, but each one of those is isolated and does not interact with its environment. Clusters represent a transition area between gas phase and bulk by allowing infra-cluster interactions, while being isolated from inter-cluster interactions. [Pg.324]

In the transition area to a biocidal effect, substances that have a defoliating action and those that suppress pollen formation should also be mentioned (17). [Pg.102]

Additional intense pre-edge features can be observed for other first-row transition metals. In cuprous containing systems, this feature arises from the Is 4p transition. As with the Is 3d transition, the intensity of the Is 4p transition depends on the coordination number and symmetry of the cuprous metal site. " A weak Is 3d transition can also be observed for cupric systems. Our laboratory has successfully applied the methodology of quantitating both Is 3d and the Is 4p transition areas to elucidate the complex mixed valence copper environment in the multicopper active sites in particulate methane monooxygenase. ... [Pg.6394]

Ground Water Geochemistry. Ground water from the lower aquifer in the lower Perch Lake Basin at the Chalk River Nuclear Laboratories, Figure 2, was used for field elution studies to provide water of different redox characteristics. Water from piezometer "0" in the transition area, and from KNEW in the discharge area was used as being representative of "neutral" and... [Pg.83]

Before we put numbers into these equations we note some qualitative predictions. Since v is roughly proportional to the number n of carbon atoms in the hydrocarbon tail, eqn (4.5) shows that (R ci R ) is proportional to n as observed. Further, Oq is independent of n. This is consistent with experiments on monolayers at the oil-water interface where the pressure-area isotherms are found to be insensitive to chain length above the transition area. As r —5- is a linear function of n. In (cmc) is also linear in n, again as observcd. ... [Pg.250]


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See also in sourсe #XX -- [ Pg.6 , Pg.9 , Pg.47 , Pg.212 , Pg.248 , Pg.268 , Pg.277 , Pg.429 , Pg.600 ]




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