Stapled design

From 1910 onward waste filament yam had been chopped into short lengths suitable for use on the machinery designed to process cotton and wool staples into spun yams. In the 1930s new plants were built specifically to supply the staple fiber markets. During World War II the production of staple matched that of filament, and by 1950, staple viscose was the most important product. The new spun-yam oudets spawned a series of viscose developments aimed at matching the characteristics of wool and cotton more closely. Viscose rayon was, after all, silk-like. Compared with wool it lacked bulk, residence, and abrasion resistance. Compared to cotton, it was weaker, tended to shrink and crease more easily, and had a rather lean, limp hand. 

Textile technology is used to mechanically or aerodynamicaHy arrange textile fibers into preferentially oriented webs. Fabrics produced by these systems are referred to as dry-laid nonwovens. Dry-laid nonwovens are manufactured with machinery associated with staple fiber processing, such as cards and gametts, which are designed to manipulate preformed fibers in the dry state. Also included in this category are nonwovens made from filaments in the form of tow, and fabrics composed of staple fibers and stitching filaments or yams, ie, stitchbonded nonwovens. 

Because fiber frictional properties are so important in the conversion of staple yams to spun yams, ASTM D2612 has been designed to measure the cohesive force encountered in the drafting or fiber alignment of sHver and top under static conditions. This frictional force is affected by surface lubrication, linear density, surface configuration, fiber length, and fiber crimp. 

The coiling together of textile staple fibres, yams or threads to give the structure the required degree of strength, extensibility, flex resistance, etc. Twist is designated as so many turns per inch and either right hand (Z) or left hand (S). See S-Twist and Z-Twist. 

The manufacturing processes for textile filament, staple and industrial filament yams have become so specialized that it is not possible to make one such class of fibers on the others equipment. Within these classes, there are production machines specialized for certain types of fibers for specific types of consumer products. Large machines designed to produce high volumes of commodity products (e.g. staple for cotton blending) at high efficiency and low cost are not well suited to the efficient production of specialty staple variants (e.g. fibers with special dyeing properties) and vice-versa. 

Modified Cross Sections. Nylon filaments are spun in a variety of cross-section shapes that include the conventional round to irregular solid and hollow shapes (Fig. 13). The cross-section shape is an important variant in designing the functionality and luster of fibers. The round cross section is used for strength in industrial applications and for subdued luster in apparel and upholstery. The multilobal cross sections are used to enhance bulk and for bright luster in both BCF and spun staple yams for carpets and upholstery. The grooves in the multilobal shapes also enhance moisture transport by wicking water through capillary action. Flat-sided ribbon-like cross sections provide cover in apparel applications. 

Fig. 21 (a) Sketch of the basic idea of DNA origami a long strand is stapled by oligonucleotides complementary to specific tracts along its sequence and is folded into designed shapes (b), as complex as a star (c). (d) AFM image of the experimental realization of (c) (edge size is 165 pm). Adapted with permission from [84]... 

From a materials science perspective, the SC is a laminated composite membrane comprised of two distinct domains, specifically, proteins (corneocyte cells with embedded keratin bundles) and lipid bilayers. Corneocyte cells have covalently attached lipids, which makes them compatible with the surrounding lipid matrix. In addition, corneocytes in different layers are held together by protein staples called desmosomes. SC has been designed to exfoliate dead cells in an orderly fashion where the upper layers come off in a layer-by-layer fashion. For this to happen, the desmosomes have to be cleaved by proteolytic enzymes in the SC as the cells approach the outermost layers. 

Scenario Suppose you re designing a small robot that picks up metallic objects (screws, staples, metal shavings, etc.)—and one of the key components for the robot is an electromagnet. DOE can help you determine the electromagnet configuration that will best meet your design criteria. 

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