Interface drawing process

The diameter of as-spun fiber decreased from around 20-30 p,m to about 15 pm after drawing, while the size of the polystyrene morphology reduced about 10%. This indicates the drawing process did not effectively deform the solid dispersed phase, because it is difficult for the draw stress to transfer from the matrix to the dispersed phase through the solid interface, and the free space for the polystyrene phase deformation is limited. 

Here, issues in relation to the trickle flow regime—isothermal operation and plug flow for the gas phase—will be dealt with. Also, it is assumed that the flowing liquid completely covers the outer surface particles (/w = 1 or aLS = au) so that the reaction can take place solely by the mass transfer of the reactant through the liquid-particle interface. Generally, the assumption of isothermal conditions and complete liquid coverage in trickle-bed processes is fully justified with the exception of very low liquid rates. Capillary forces normally draw the liquid into the pores of the particles. Therefore, the use of liquid-phase diffusivities is adequate in the evaluation of intraparticle mass transfer effects (effectiveness factors) (Smith, 1981). 

Fig. 6. Image sequence of a growing carbon nanofiber (movies are available as supplementary information to Reference (52) and can be found in Reference (57)). Images (A)-(H) illustrate one cycle in the elongation/contraction process. Drawings are included to guide the eye in locating the positions of mono-atomic nickel step edges at the carbon-nickel interface. The images are acquired in situ with CH4 H2 = 1 1 at a total pressure of 2.1 mbar with the sample heated to 809 K. All images were obtained at a rate of 2 frames/s. Scale bar = 5 nm. Reprinted with permission from Reference (52).

Pneumatic hookups Process connection drawings Instrument/electrical interface Earthing schedule and drawings Cable/tubing routing drawings Cable and termination schedules Cabinet/rack layout Control room layout Operator console/station(s)... 

Figure 3. Streamlines (on right) and isotherms (on left) for growth of Si in a prototype Czochralski system. The volume of the melt, at the bottom in each drawing, changes among the calculations, affecting the qualitative form of the convection cell and the shape of the crystal interface. From Theory of Transport Processes in Single Crystal Growth from the Melt, by R. A. Brown, AIChE Journal, Vol. 34, No. 6, pp. 881 -911, 1988 [29]. Reproduced by permission of the American Institute of Chemical Engineers copyright 1988 AIChE.

Fig. 2 Description of the craze thickening process according to Kramer [31] as drawing in new polymer chains from the craze/bulk interface into the fibrils. The fibrils have a diameter D and spacing of D0...

As discussed in Sect. 3.2, once a mature fibril is created, further thickening occurs by a viscoplastic drawing mechanism which involves intense plastic deformation at the craze/bulk interface [32], Instead of using a non-Newtonian formulation as in [32] or a formulation based on Eyring s model [45], but on the basis of a preliminary study of the process [36], the craze thickening is described with a similar expression as the viscoplastic strain rate for the bulk in Eq. 3 as [20]... 

The solvent extraction process of metal ions inherendy depends on the mass transfer across the interface and the reaction that occurs at the interfacial region. Therefore, the elucidation of the kinetic role of the interface was very important in order to clarify the extraction mechanism and to control the extraction rates. In 1982, Watarai and Preiser invented the high-speed stirring (HSS) method [4,5]. Figure 10.1 shows the schematic drawing of the HSS method [6]. When a two-phase system is vigorously stirred in a... 

Many of the disadvantages of ram extrusion are eliminated in hydrostatic extruaon, where the piston is replaced by high pressure fluid. As shown in Fig. 15, the billet stands clear of the cylinder walls, so that this element of friction is eliminated. The pressure transmitting fluid also lubricates the interface between the die and the billet, so that the deformation is essentially plug-flow (i.e. an extensional deformation, identical to drawing polymer with a free surface). Homogeneous oriented sections are therefore produced. A small haul-off force is applied to provide control of the extrusion process, and this also serves to ensure that the extrudates are straight. 

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