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CYLINDRICAL-SURFACE

The linearized Poisson-Boltzmann equation yields the interaction potential between a polyelectrolyte chain and the surface of an infinitely long, uniformly [Pg.23]

As displayed in Fig. 10, reveals a crossover from a planar-like scaling ffc (jca) for Ka 1 to the dependence Tc (ku) fonca 1. The latter relation follows by an asymptotic expansion of the Bessel functions Ti(K a) for small arguments, which yields  [Pg.24]

In the adsorbed state, the eigenfunctions J/ follow from (36). In particular, the asymptotic radial dependence of the eigenfunction in the regime r ro can be determined. Here, is given by  [Pg.24]

The radial polyelectrolyte density profile follows from  [Pg.24]

The reference point p is not essential for the geometric definition of axis cylindrical surface but it is essential for the unique parameteri-sation. [Pg.83]

reference point should be distinct from axis point and should lie approximately in the plane through point normal to a. [Pg.83]


Let us consider the scheme showed in Fig. I to calculate the field scattered by a rough cylindrical surface (i.e. a wire). The wire is illuminated by a monochromatic, linearly polarized plane wave at an angle of incidence a with its axis of symmetry. The surface is described, in a system fixed to the wire, by p = h (cylindrical coordinates. We shall denote the incident wave vector lying on the x-z plane as kj and the emergent wave vector simply as k. [Pg.663]

Now we intend to derive nonpenetration conditions for plates and shells with cracks. Let a domain Q, d B with the smooth boundary T coincide with a mid-surface of a shallow shell. Let L, be an unclosed curve in fl perhaps intersecting L (see Fig.1.2). We assume that F, is described by a smooth function X2 = i ixi). Denoting = fl T we obtain the description of the shell (or the plate) with the crack. This means that the crack surface is a cylindrical surface in R, i.e. it can be described as X2 = i ixi), —h < z < h, where xi,X2,z) is the orthogonal coordinate system, and 2h is the thickness of the shell. Let us choose the unit normal vector V = 1, 2) at F,, ... [Pg.19]

Fiber friction can be deterrnined by physical methods. For rapid evaluation of fiber or yam friction, the capstan method is used, where a yam or fiber is pulled over a cylindrical surface. The frictional coefficient, ]1, can be determined according to the formula... [Pg.454]

Concentric spherical or infinite cylindrical surface zones, Ai inside = 1 f ai = Ai/Aa)... [Pg.585]

Cylindrical Boundary Layer Laminar boundary layers on cylindrical surfaces, with flow parallel to the cylinder axis, are described by Glauert and LighthiU Proc. R. Soc. [London], 230A, 188-203 [1955]), Jaffe and Okamura (Z. Angety. Math. Phys., 19, 564—574 [1968]) and Stewartson ((J. Appl Math., 13, 113-122 [1955]). For a turbulent boundaiy layer, the total drag may be estimated as... [Pg.666]

FIG. 6 48 Continuous surface a) continuous flat surface, (h) continuous cylindrical surface. (From Sakiadis, Am. Inst. CLem. Eng. J., 7, 221, 467 [19611)... [Pg.667]

Continuous Cylindrical Surface The continuous surface shown in Fig. 6-48b is apphcable, for example, for a wire drawn through a stagnant fluid (Sakiadis, AIChE ]., 7, 26-28, 221-225, 467-472 [1961]). The critical-length Reynolds number for transition is Re = 200,000. The laminar boundary laver thickness, total drag, and entrainment flow rate may be obtained from Fig. 6-49 the drag and entrainment rate are obtained from the momentum area 0 and displacement area A evaluated at x = L. [Pg.667]

Tallmadge and Gutfinger Jnd. Eng. Chem., 59[11], 19-34 [1967]) discuss prediction of drainage rates from liquid films on flat and cylindrical surfaces. [Pg.669]

The suction gas which enters from the periphery is trapped by the scrolls. The closed volumes move radially inward until the discharge port is reached, when vapor is pressed out. The orbiting scroll is driven by a short-throw crank mechanism. Similar to screw compressors, internal leakage should be kept low, and is occurring in gaps between cylindrical surfaces and between the tips of the involute and the opposing scroll base plate. [Pg.1112]

Of particular importance to carbon nanotube physics are the many possible symmetries or geometries that can be realized on a cylindrical surface in carbon nanotubes without the introduction of strain. For ID systems on a cylindrical surface, translational symmetry with a screw axis could affect the electronic structure and related properties. The exotic electronic properties of ID carbon nanotubes are seen to arise predominately from intralayer interactions, rather than from interlayer interactions between multilayers within a single carbon nanotube or between two different nanotubes. Since the symmetry of a single nanotube is essential for understanding the basic physics of carbon nanotubes, most of this article focuses on the symmetry properties of single layer nanotubes, with a brief discussion also provided for two-layer nanotubes and an ordered array of similar nanotubes. [Pg.27]

In direct space successive layers are sheared homogeneously along cylindrical surfaces, one relative to the adjacent one, as a consequence of the circumference increase for successive layers. In diffraction space the locus of the corresponding reciprocal lattice node is generated by a point on a straight line which is rolling without sliding on a circle in a plane perpendicular to the tube axis. Such a locus... [Pg.19]

It is known that a metallic ID system is unstable against lattice distortion and turns into an insulator. In CNTs instabilities associated two kinds of distortions are possible, in-plane and out-of-plane distortions as shown in Fig. 8. The inplane or Kekuld distortion has the form that the hexagon network has alternating short and long bonds (-u and 2u, respectively) like in the classical benzene molecule [8,9,10]. Due to the distortion the first Brillouin zone reduees to one-third of the original one and both K and K points are folded onto the F point in a new Brillouin zone. For an out-of-plane distortion the sites A and B are displaced up and down ( 2) with respect to the cylindrical surface [11]. Because of a finite curvature of a CNT the mirror symmetry about its surface are broken and thus the energy of sites A and B shift in the opposite direction. [Pg.69]

The electron wave function becomes localised in the top and bottom part of the cylindrical surface where the effective magnetic field perpendicular to the tube surface is the largest. Thus the boundary condition along the circumference direction becomes less important in high magnetic fields as has been discussed in Sec. 2. Consequently the distinction between metallic and semiconducting... [Pg.71]

The following Stefan-Boltzmann formula applies to both plane and cylindrical surfaces ... [Pg.112]

This type normally has a long cylindrical impeller having a relatively large number of shallow forward-curved blades. Due to the shape of the casing surrounding this impeller, air enters all along one side of the cylindrical surface of the impeller and leaves on another side. Static efficiency is typically 40-50 per cent. [Pg.424]

Can handle most thermoplastics. A big application area is bottles. Flat, concave or cylindrical surfaces. [Pg.705]

For the region of fully developed flow in a pipe of length L, diameter d and radius r, the rate of flow of heat Q through a cylindrical surface in the fluid at a distance y from the wall is given by ... [Pg.422]

Taking area 1 as that of the plate, area 2 as the underside of the hemisphere, area 3 as an imaginary cylindrical surface linking the plate and the underside of the dome which represents the black surroundings and area 4 as an imaginary disc sealing the hemisphere and parallel to the plate, then, from equation 9.134, the net radiation to the surface of the plate 1 is given by ... [Pg.455]

Taking surface 1 as the heater, surface 2 as the heated plate and surface 3 as an imaginary enclosure consisting of a vertical cylindrical surface representing the surroundings, then, for each surface ... [Pg.464]

Powia i. R.W. and Griffiths. F.. Trans. Inst. Client. Eng. 13 (1935) 175. The evaporation of water from plane and cylindrical surfaces. [Pg.656]

The velocity distribution and frictional resistance have been calculated from purely theoretical considerations for the streamline flow of a fluid in a pipe. The boundary layer theory can now be applied in order to calculate, approximately, the conditions when the fluid is turbulent. For this purpose it is assumed that the boundary layer expressions may be applied to flow over a cylindrical surface and that the flow conditions in the region of fully developed flow are the same as those when the boundary layers first join. The thickness of the boundary layer is thus taken to be equal to the radius of the pipe and the velocity at the outer edge of the boundary layer is assumed to be the velocity at the axis. Such assumptions are valid very close to the walls, although significant errors will arise near the centre of the pipe. [Pg.682]

A chemical reactor, 1 m in diameter and 5 m long, operates at a temperature of 1073 K, It is covered with a 500 mm thickness of lagging of thermal conductivity 0.1 W/m K. The heat loss from the cylindrical surface to the surroundings is 3.5 kW. What is the heat transfer coefficient from the surface of the lagging to the surroundings at a temperature of 293 K How would the heat loss be altered if the coefficient were halved... [Pg.850]

Figure 13 illustrates the principle of using FTR to measure the lubricating him thickness. A sapphire prism (AI2O3), the lubricant, and a steel specimen (steel ring, GCrjs) constitute the three media of FTR. The bottom surface of the sapphire prism and the cylindrical surface of the specimen form... [Pg.13]

Fig. 2.6.9 Visualization of gas flow through a cylindrical surface represents the rock, (b) Only porous sandstone rock. A 3D phase encoding a slice through the center of the rock is sequence with a hard encoding pulse was used, displayed, showing the origin of the gas that is (a) 3D representation of an isochronal surface flowing through the detector at different times at different times after the encoding step. The after the tagging [figure taken from 43]. Fig. 2.6.9 Visualization of gas flow through a cylindrical surface represents the rock, (b) Only porous sandstone rock. A 3D phase encoding a slice through the center of the rock is sequence with a hard encoding pulse was used, displayed, showing the origin of the gas that is (a) 3D representation of an isochronal surface flowing through the detector at different times at different times after the encoding step. The after the tagging [figure taken from 43].
The turbine type of helicity in canals is a toroidal turbine, and can occur with proper rotation axes and with 2V 42, 63 screw axes, and depends on the object rotated. It is necessary that a distinctive principal plane or axis of the host molecule or molecular fragment be canted in the cylindrical surface of the canal so that it is neither parallel to or perpendicular to the axis of the canal. No unequivocal instance of this type of helical canal has been reported. The cyclodextrin unimolecular hosts 3 4) might be... [Pg.148]

As the name implies, the cup-and-bob viscometer consists of two concentric cylinders, the outer cup and the inner bob, with the test fluid in the annular gap (see Fig. 3-2). One cylinder (preferably the cup) is rotated at a fixed angular velocity ( 2). The force is transmitted to the sample, causing it to deform, and is then transferred by the fluid to the other cylinder (i.e., the bob). This force results in a torque (I) that can be measured by a torsion spring, for example. Thus, the known quantities are the radii of the inner bob (R ) and the outer cup (Ra), the length of surface in contact with the sample (L), and the measured angular velocity ( 2) and torque (I). From these quantities, we must determine the corresponding shear stress and shear rate to find the fluid viscosity. The shear stress is determined by a balance of moments on a cylindrical surface within the sample (at a distance r from the center), and the torsion spring ... [Pg.60]

The three-dimensional APH display may be conveniently chosen to map onto a simple cylindrical surface (e.g., a coffee cup) by adding blank filling space to each helical turn in order to maintain a constant radius of curvature. Figure B.3 provides a simple planar template that one can cut and paste to form the APH cylindrical display. [Pg.718]

Figure B.3 The ascending periodic helix (APH) of the chemical elements, showing the evident relationship to the LST form (Fig. B.2). The heavy vertical line marks the start of each new turn. The diagram can be pasted onto a smooth cylindrical surface by joining element 88 with element 89 and element 56 with element 57 at the cylindrical seam. Figure B.3 The ascending periodic helix (APH) of the chemical elements, showing the evident relationship to the LST form (Fig. B.2). The heavy vertical line marks the start of each new turn. The diagram can be pasted onto a smooth cylindrical surface by joining element 88 with element 89 and element 56 with element 57 at the cylindrical seam.
Apply the conservation of energy, Equation (3.40). Since the control volume is fixed the pressure work term does not apply. The shear work (v x shear force) is zero because (a) the radius of the control volume was selected so that the velocity and its gradient are zero on the cylindrical face and (b) at the base faces, the velocity is normal to any shear surface force. Similarly, no heat is conducted at the cylindrical surface because the radial temperature gradient is zero, and conduction is ignored at the bases since we assume the axial temperature gradients are small. However, heat is lost by radiation as... [Pg.68]

Kankare, J. and Vinokurov, I. A. (1999). Kinetics of Langmuirian adsorption onto planar, spherical, and cylindrical surfaces, Langmuir, 15, 5591-5599. [Pg.203]


See other pages where CYLINDRICAL-SURFACE is mentioned: [Pg.662]    [Pg.693]    [Pg.696]    [Pg.845]    [Pg.143]    [Pg.355]    [Pg.628]    [Pg.1103]    [Pg.479]    [Pg.532]    [Pg.35]    [Pg.112]    [Pg.113]    [Pg.870]    [Pg.42]    [Pg.122]    [Pg.281]    [Pg.149]    [Pg.60]    [Pg.718]   
See also in sourсe #XX -- [ Pg.36 ]

See also in sourсe #XX -- [ Pg.82 ]




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Adhesion of Cylindrical Particles to Rough Surfaces

Concentric cylindrical surfaces

Cylindrical Shell Surfaces of the Vessel

Film on a Cylindrical Surface

Heat exchangers cylindrical surfaces

Potential distribution around cylindrical surfaces

Surface pressure measurements with a cylindrical rod

Surfaces, charged cylindrical

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