Fiber show

Fig. 1. Typical longitudinal section of bast fiber showing very long fiber strands composed of many ultimate fibers (see Table 3 for dimensions).

The copolymer fiber shows a high degree of drawabiUty. The spun fibers of the copolymer were highly drawn over a wide range of conditions to produce fibers with tensile properties comparable to PPT fibers spun from Hquid crystalline dopes. There is a strong correlation between draw ratio and tenacity. Typical tenacity and tensile modulus values of 2.2 N/tex (25 gf/den) and 50 N/tex (570 gf/den), respectively, have been reported for Technora fiber (8). 

Fig. 2. Single cotton fibers, showing ratio of length to width.

Fig. 2. Vapour-grown carbon fiber. showing relatively early stage of growth at the tip the seeded Fe catalytic particle is encapsulated.

The heat of fusion of the rotator phase in n-paraffms is 38-40 cal/g, while AHo- m for PE irradiated with 1000 Mrad is about 29 cal/g. The corresponding value of AHo->m for hexagonal PE at high pressure (500 MPa) is only around 15 cal/g. Thermograms of constrained PE fibers showed similarly low heats of fusion of the hexagonal phase. 

In recent years, prices for natural fibers were not stable, especially for flax fibers. Flax fibers, showing the highest values for strength (Table 2), are about 30% more expensive than glass fibers. Additionally, is price depends on the fiber preparation. Usually, glass fibers are delivered pretreated, i.e., treated with different sizes... 

When used as substitutes for asbestos fibers, plant fibers and manmade cellulose fibers show comparable characteristic values in a cement matrix, but at lower costs. As with plastic composites, these values are essentially dependent on the properties of the fiber and the adhesion between fiber and matrix. Distinctly higher values for strength and. stiffness of the composites can be achieved by a chemical modification of the fiber surface (acrylic and polystyrene treatment [74]), usually produced by the Hatschek-process 75-77J. Tests by Coutts et al. [76] and Coutts [77,78] on wood fiber cement (soft-, and hardwood fibers) show that already at a fiber content of 8-10 wt%, a maximum of strengthening is achieved (Fig. 22). 

We have found that high molecular weight poly (p-PIN)s readily yields fibers by manual drawing from the melt. X-ray analysis of melt-drawn fibers showed a characteristic amorphous halo with a d spacing at 6.2 A. 

Figure 1. Immunofluorescent labeling of dystrophin in the Xp21 muscular dystrophies. In normal muscle, clear uniform labeling is present at the membrane of each muscle fiber. In Becker muscular dystrophy (BMD), there is inter- and intrafiber variation in labeling intensity. In Duchenne muscular dystrophy (DMD), most fibers are devoid of labeling (note, however, that in most biopsies occasional fibers exhibit weak labeling). In the biopsy from a manifesting carrier, some fibers show normal labeling and others are negative. In the former, the normal X-chromosome is active while in the latter the abnormal X-chromosome is active.

In severe neonatal nemaline myopathy virtually every muscle fiber shows multiple rods and all muscle fiber types are affected. However in juvenile cases, two different patterns of fiber type involvement are seen. In one there is a clear size difference between type 1 fibers, which are abnormally small (hypotrophic or atrophic) and which contain numerous nemaline rods, and type 2 fibers, which are either of normal diameter or hypertrophic and contain few, if any, nemaline rods. Other patients show a gross predominance of type 1 muscle fibers, again with rods virtually confined to this fiber type. These findings may be explicable in terms of the involvement of isoforms of a-actinin specific to slow and fast muscle fiber types. 

Fatal infantile cytochrome c oxidase (CCO) deficiency is characterized by total absence of catalytic activity in skeletal muscle. This often occurs within the context of the Fanconi syndrome, or less commonly in association with a cardiomyopathy. Although the deficiency is global in skeletal muscle, with all fibers affected, only isolated scattered fibers show abnormal aggregations of mitochondria (ragged-red fibers). Multiple affected siblings within one family are frequently encountered and suggest autosomal recessive inheritance. The condition normally proves fatal before the age of six months and is characterized by worsening intractable lactic acidemia. 

Figure 16. Werdnig-Hoffman disease most muscle fibers show severe atrophy with some type 1 (dark) fibers showing hypertrophy.

Figure 23. Steroid-induced atrophy affecting type 2B fibers selectively these fibers show intermediate ATPase reactivity after pH 4.6 preincubation.

A comparison of bromine and phosphorus compounds on the flammability of PET fiber shows phosphorus (as phosphine oxide) to be 3.7 times more effective than bromine (Table 1). No synergy was observed. Nevertheless, phosphorus was shown to be more effective than antimony normally used as a synergist, resulting in a higher oxygen index at a lower concentration (Table 2). 

High temperature tensile tests of the C/SiC coated C-fiber showed very good oxidation resistance up to 650°C. The filaments of the fiber bundle were coated homogeneously. 

Figure 8. (a) Schematic structure of carbon fibers and (b) an SEMof a Melblon 3100 fiber showing the fiber and internal structure of a fracture. 

The HRTEM observation of the cross section of a coated fiber showed that the core is constituted of aromatic layers highly misoriented, whereas they are preferentially oriented in parallel for the thin coating pairs of stacked layers form mainly Basic Structural Units (BSUs) in which the average interlayer distance is smaller than between the aromatic layers in the bulk of the fiber. Since the nanotexture is more dense for the pyrolytic carbon than for the fiber itself, it acts as a barrier which prevents the diffusion of the large solvated lithium ions to the core of the fiber, allowing the passivation layer to be less developed after this treatment. Hence, the major amount of lithium inserted is involved in the reversible contribution therefore this composite material is extremely interesting for the in-situ 7Li NMR study of the reversible insertion. 

Partially graphitized cokes produced by means of thermal decomposition of organic raw materials, polymers and graphitized carbon fibers show a good performance [1,2,6-17]. The properties of carbon materials are often improved due to large amounts of dopants (H, O, S, N, P, Si, etc.) [9,18],... 

FTIR is also an effective way to assess the orientation or alignment of CNTs since the absorption is much stronger when the electric field of the incident light wave is parallel to the axis of aligned CNTs. The anisotropic feature has been found in SWNT-PAN composite [164], The infrared spectra of PAN fibers for the two polarization directions (parallel and perpendicular) are comparable, while the composite fibers show significant differences in the two polarization directions. 

SA fiber showed high tensile strength and modulus of over 2.5 GPa and over 300 GPa, respectively. The initial strength was preserved after heat-treatment... 

The calculation result using these values is presented in Fig. 31. As can be seen from this figure, the felt material of the titania/silica fiber showed an extremely... 

Silk fibers or monolayers of silk proteins have a number of potential biomedical applications. Biocompatibility tests have been carried out with scaffolds of fibers or solubilized silk proteins from the silkworm Bombyx mori (for review see Ref. [38]). Some biocompatibility problems have been reported, but this was probably due to contamination with residual sericin. More recent studies with well-defined silkworm silk fibers and films suggest that the core fibroin fibers show in vivo and in vivo biocompatibility that is comparable to other biomaterials, such as polyactic acid and collagen. Altmann et al. [39] showed that a silk-fiber matrix obtained from properly processed natural silkworm fibers is a suitable material for the attachment, expansion and differentiation of adult human progenitor bone marrow stromal cells. Also, the direct inflammatory potential of silkworm silk was studied using an in vitro system [40]. The authors claimed that their silk fibers were mostly immunologically inert in short and long term culture with murine macrophage cells. 

Pineapple fiber showed higher (86.7%) antioxidant activity than orange peel fiber (34.6%), and myricetin was the major polyphenol identified in pineapple fiber (Larrauri and others 1997). 

Dry heat treatment (Figure 13.12), hydrothermal treatment (Figure 13.13), dependent on temperature, as well as swelling the fibers in tetrachloroethane (Figure 13.14), produces a fiber morphology resembling that of known pictures of fracture. Swollen fibers show the typical shapes which cause the breaks in the manufacturing process. 

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