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Films, of uneven thickness

This result shows that the hydrostatic equilibrium in the transition region is ensured by simultaneous variation of a and 11. Equation 5.152 represents a generalization of Equation 5.138 for a film of uneven thickness and axial symmetry. Generalization of Equations 5.150 through 5.152 for the case of more complicated geometry is also available. ... [Pg.188]

The problem for the interactions upon central collisions of two axisymmetric particles (bubbles, droplets, or solid spheres) at small surface-to-surface distances was first solved by Reynolds" and Taylor for solid surfaces and by Ivanov et for films of uneven thickness. Equation 5.255... [Pg.224]

The problem for the interactions upon central collisions of two axisymmetric particles (bubbles, droplets, or solid spheres) at small surface-to-surface distances was first solved by Reynolds [646] and Taylor [653,654] for solid surfaces and by Ivanov et al. [655,656] for films of uneven thickness. Equation 4.266 is referred to as the general equation for films with deformable surfaces [655,656] (see also the more recent reviews [240,657,658]). The asymptotic analysis [659-661] of the dependence of the drag and torque coefficient of a sphere, which is translating and rotating in the neighborhood of a solid plate, is also based on Equation 4.266 applied to the special case of stationary conditions. [Pg.345]

The gap between two particles, like those depicted in Figure 1, can be considered as a liquid film of uneven thickness. The calculation of the particle-particle interaction energy can be reduced to the simpler calculation of the interaction across a plane-parallel film by using the Derjaguin formula see Eq. (182). This is the reason why in this review we will pay much attention to the plane-parallel films. [Pg.303]

The gap between two colliding particles (bubbles, droplets, solid particles, surfactant micelles) in a colloidal dispersion can be treated as a film of uneven thickness. Then, it is possible to utilize the theory of thin films to calculate the energy of interaction between two colloidal particles. Deijaguin [276] has derived an approximate formula which expresses the energy of interaction between two spherical particles of radii and i 2 through integral of the excess surface free energy per unit area, f h), of a plane-parallel film of thickness h [see Eq. (161)] ... [Pg.356]

A. Films of Uneven Thickness Between Colliding Fluid Particles... [Pg.383]

Fig. 3-34. Influences that affect performance of film during windup, (a) Effect of tension, (b) Effect of uneven thickness. Fig. 3-34. Influences that affect performance of film during windup, (a) Effect of tension, (b) Effect of uneven thickness.
The content of boron amounts to about 10 cm, resulting in a specific resistance of less than 0.1 Qcm. UltrananocrystaUine diamond films also suit well to coating electrodes. Even at a low thickness of layers a complete and dense covering of the support is achieved, and the coating of unevenly shaped electrodes is easier. [Pg.447]

The principle of evaporation is relatively simple.PII l The coating material (known as the source) is heated at low pressure (<10 Pa) above its boiling point, sending atoms or molecules, through a cosine distribution of trajectories, in a straight line to the substrate, where these condense to form a thin film. At such low pressure, the mean-free path is large compared to the distance between source and substrate and few collisions occur before the species condense on the substrate. This leads to uneven thickness buildup since the thickest part of the coating will that which is closest to the source. To compensate for that, planetary substrate holders and multiple sources may be used. [Pg.292]

Comparing this with the research history of polyacetylene, both cases are analogously situated since both polyacetylene and polythiophene were intractable, their chemical and stmctural characterization was quite difficult in the conventional powder form [6,9], However, the polymer films of high quality prepared via either the Shirakawa method [7] or the electrochemical routes [10-12] have enabled easier characterization and the systematic research of polyacetylene and polythiophene. That is, the materials both in a thick free-standing form and in a thin on-substrate form are free from uneven particles which cause irregular scattering of light and yield contact resistance between those particles. This allows us to record sharply resolved spectra and to measure the intrinsic conductivity of the materials. [Pg.310]

As a result, the barrier quality of the AlO -layer is improved (see barrier improvement factors for laminates with AlO, Table 21-4 for laminates 4. and 6.). Since the aluminum layers directly sputtered onto the substrate film have a thickness of only 20-50 nm, they replicate the structure of the polymer on their upper side. In general, thin layers of inorganic oxides caimot level out unevenness on the polymer surface, and even in the best case they leave the surfaces rmaltered (Langowski, 2001). [Pg.1659]

The mainstream method at that time of producing a pressure-sensitive adhesive tape was to coat the adhesive directly onto the substrate. However, there was no technology to precisely coat the adhesive material onto the polarizers that had a low scratch threshold and low heat resistance. There were very difficult problems of contamination and air bubbles, limits to the drying process, and the strict demand for small refractive index anisotropy. Slight uneven thickness of the adhesive will lead to defects in the display, even for pressure-sensitive adhesives. AU this was completely different from the demands of customers of electronic adhesive tape so far. The aforementioned problems all led to visible optical distortions in the polarizer film. For this reason, the coating facility to apply the adhesive had to be installed in a clean room, the coating method of the pressure-sensitive adhesive transfer had to be studied, a stacked twist suppression technology had to be established, and the formation of microcrystals in the pressure-sensitive adhesive had to be suppressed, to satisfy customer requirements. [Pg.84]

In thin fiat liquid films (oil and aqueous thin films, thin films of aqueous electrolyte and surfactant solutions, and both free films and films on solid substrates), the disjoining pressure acts alone and determines their thickness. However, if the film surface is curved or uneven, both the disjoining and the capillary pressures act together. In the case of partial wetting, their simultaneous action is expected to yield nonfiat equilibrium shapes. For instance, due to the S-shaped disjoining pressure isotherm, microdrops, microdepressions, and equilibrium periodic films could exist on fiat solid substrates. We shall establish a criteria for both existence and stability of such nonfiat equilibrium liquid shapes. On the other hand, we... [Pg.41]

Two component, positive photoresists (see Section 3.5.b) represent systems with unusual exposure characteristics caused by the standing wave effect (see Section 2.1.f) and "bleaching" or change in optical density during exposure (see Sections 3.5 and 3.9). Both of these phenomena result in nonlinear exposure throughout the thickness of the resist film, and result in uneven developing rates as a function of film thickness, making evaluation of these systems difficult. [Pg.201]


See other pages where Films, of uneven thickness is mentioned: [Pg.636]    [Pg.356]    [Pg.636]    [Pg.356]    [Pg.352]    [Pg.491]    [Pg.474]    [Pg.87]    [Pg.5]    [Pg.412]    [Pg.527]    [Pg.3058]    [Pg.197]    [Pg.172]    [Pg.224]    [Pg.88]    [Pg.244]    [Pg.301]    [Pg.5]    [Pg.135]    [Pg.168]    [Pg.147]    [Pg.1005]    [Pg.153]    [Pg.231]    [Pg.545]    [Pg.259]    [Pg.346]    [Pg.574]    [Pg.684]    [Pg.43]    [Pg.219]    [Pg.370]    [Pg.68]    [Pg.198]    [Pg.151]    [Pg.258]   
See also in sourсe #XX -- [ Pg.356 ]




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Thick films

Unevenness

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