Cross-sectional shape

Slurry or slip casting provides a relatively inexpensive way to fabricate unifonn-thickness, thin-wall, or large cross section shapes [4o, 44, 45, 46, 42 aiid 48]. For slip casting, a slurry is first poured into a porous mould. Capillary suction then draws the liquid from the slurry to fonn a higher solids content, close-packed, leather-hard cast on the inner surface of the mould. In a fixed time, a given wall thickness is fonned, after which the excess slurry is drained. 

Curvature and rotation lenses correct for any imperfections (aberrations) in the cross-sectional shape of the beam before it reaches the collector slit. The curvature lens provides a means of changing any banana-shaped beam cross-section into a rectangular shape (Figure 24.8). The rotation lens rotates the beam such that the sides of the beam become parallel with the long axis of the collector slit (Figure 24.8). 

The geometry of the cylinder is a matter of convenience. Except for numerical coefficients, the results we shall obtain will apply to plates of any cross-sectional shape. 

Cross-linking cotton Cross-linking systems Cross ozomdes Cross-section shapes Crotarbital [1952-67-6]... 

Yarns and Fibers. Many different acetate and triacetate continuous filament yams, staples, and tows are manufactured. The variable properties are tex (wt in g of a 1000-m filament) or denier (wt in g of a 9000-m filament), cross-sectional shape, and number of filaments. Individual filament fineness (tex per filament or denier per filament, dpf) is usually in the range of 0.2—0.4 tex per filament (2—4 dpf). Common continuous filament yams have 6.1, 6.7, 8.3, and 16.7 tex (55, 60, 75, and 150 den, respectively). However, different fabric properties can be obtained by varying the filament count (tex per filament or dpf) to reach the total tex (denier). 

Although the cross-sectional shape of the spinneret hole direcdy affects the cross-sectional shape of the fiber, the shapes are not identical. Round holes produce filaments with an approximately round cross section, but with crenelated edges triangular holes produce filaments in the form of a "Y." Different cross sections are responsible for a variety of properties, eg, hand, luster, or cover, in the finished fabric. Some fibers may contain chemical additives to provide light-fastness and impart fire retardancy. These are usually added to the acetate solution before spinning,... 

Fig. 13. Typical nylon fiber cross-section shapes.

Transverse Dimensions or Fineness. Historically, the quantity used to describe the fineness or coarseness of a fiber was the diameter. Eor fibers that have irregular cross-sections or that taper along their lengths, the term diameter has no useful meaning. Eor cylindrical fibers, however, diameter is an accurate measurement of the transverse dimension. Though textile fibers can be purchased in a variety of cross-sectional shapes, diameter is stiU a useful descriptor of the transverse dimension. Eiber diameter is important in determining not only the ease with which fibers can be twisted in converting them to yams, but also fiber stiffness, ie, fabric stiffness, and, alternatively, fabric softness and drapeabiHty. 

Gross-Sectional Shape. Fibers vary in cross-sectional shape both naturally and by design (1,2,19). Whereas wool fibers are essentially round, cotton fibers are eUiptical or kidney-shaped. In synthetic fibers, the cross-sectional shape is deterrnined by the method of spinning and the shape of the spinnerette hole through which the fiber is extmded (3,22). 

ASTM D629 describes procedures for determining cross-sectional shapes for natural fibers using microscopic analysis. Cross-sectional shape of synthetic fibers also can be verified by using microscopic analysis. 

When the bulk containing the binder is uniform, it is compressed on pneumatic, hydraulic, or ram-type presses. Compression can be carried out in presses provided with suitably designed cavities or in metallic pans. The pans ate filled with the powder mass, and a plunger with a cross-sectional shape similar to that of the pan is used to compress the tablet. The resulting tablets ate commonly used with powder puffs or cosmetic bmshes. 

Mechanical adhesion. Mechanical interlocking between the two substrates can also contribute to adhesion. This mechanism would function most effectively with fibers with rough surfaces and irregular or non-circular cross-sectional shapes. 

Welded or seamless pipe used for structural or load-bearing applications in aboveground installations. Fabricated in nominal wall thicknesses and sizes to ASTM specifications in round, square, rectangular and other cross-sectional shapes. 

Figure 7-27 Nominal Stiffener Cross-Sectional Shapes...

COSSETTES Slender strips of beets, ideally with a V cross-sectional shape, cut by slicing machinery prior to extraction of sucrose by diffusion. 

Monta, N., Whitfill, D.L., and Wahl, H.A. "Stress Intensity Factor and Fracture Cross Sectional Shape Precictions From a 3 0 Model for Hydraulically Induced Fractures," SPE paper 14262, 1985 SPE Annual Technical Conference and Exhibition, Las Vegas, September 22 25. 

In addition to the lengths of polymer molecules, the cross-sectional shapes have a major effect on their hardness and thermal stability. Aliphatics (paraffins, polyethylene, etc.) have the most simple cross-sectional shapes. Their simple and relatively symmetric shapes allow them to slide past on another readily via a process called reptation (de Gennes, 1990). As a result, linear polyethylene is relatively soft (Figure 13.1). 

The cross-sectional shapes of Nylon chains have oxygen and nitrogen atoms protruding so they are less symmetric than polyethylene chains. Along with... 

If the diameter is increased, the pressure drop along the stream decreases rapidly as 1 /If25, where D depends on the cross-sectional shape of the tube. 

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