Fibrils shape

As shown in Fig. IIB, dispersion morphology for the nylon 6/Vectra B/SA-g-EPDM blend was totally different from that of the PBT-Vectra A-SA-g-EPDM blend. TLCP phases were very uniformly and finely dispersed in the nylon 6-Vectra B-SA-g-EPDM blend and a large fibril shape observed in the PBT-Vectra A-SA-g-EPDM blend could not be seen under polarized microscope. It should be noted that the size of the dispersed TLCP phase is very small (submicron size). This small size of the TLCP phase in the nylon 6/elastomer matrix was not observed by any others [4,54,55,58]. A closer look by SEM more clearly revealed the dispersion of Vectra B in the matrix (Fig. 12B). TLCP phases are very... 

Figure 32 serves to illustrate diagrammatically how the present model would account for the changes in fibril shape under the two different... 

In synthetic fibers, the micelles are different from those in many other polymer products. The micelles in synthetic fibers often have the fibril shape, with diameters ranging from several nm to 100 nm. The lengths of fibrils depend on the polymer type and the processing conditions. This leads to a fringed fibril model. Figure 3.14 shows a basic fringed fibril model. The bonding between fibrils is relatively weak, and hence fibrils actually can be observed in fracture studies of some synthetic fibers. 

The paste-extmsion process includes the incorporation of ca 16—25 wt % of the lubricant (usually a petroleum fraction) the mixture is roUed to obtain uniform lubricant distribution. This wetted powder is shaped into a preform at low pressure (2.0—7.8 MPa or 19—77 atm) which is pushed through a die mounted in the extmder at ambient temperature. The shear stress exerted on the powder during extmsion confers longitudinal strength to the polymer by fibrillation. The lubricant is evaporated and the extmdate is sintered at ca 380°C. 

The body temperature limits for health in terms of internal or core temperature are fairly limited. The limits are basically related to the function of nervous tissue. Body temperatures around 28 °C or less can result in cardiac fibrillation and arrest. Temperatures of 43 °C and greater can result in heat stroke, brain damage, and death. Often, too high a temperature causes irreversible shape changes to the protein molecules of nervous tissue. That is, cooling overheated tissue to normal temperatures may not restore its original function. 

In order to supplement micro-mechanical investigations and advance knowledge of the fracture process, micro-mechanical measurements in the deformation zone are required to determine local stresses and strains. In TPs, craze zones can develop that are important microscopic features around a crack tip governing strength behavior. For certain plastics fracture is preceded by the formation of a craze zone that is a wedge shaped region spanned by oriented micro-fibrils. Methods of craze zone measurements include optical emission spectroscopy, diffraction... 

Frequency-selective REDOR (fsREDOR) is a very powerful technique developed for the study of 13C and 15N uniformly labeled peptides or proteins [92]. The basic idea of this technique is to combine REDOR and soft n pulses to recouple a selected 13C-15N dipole-dipole interaction in a multiple-spin system. Usually one could use Gaussian shaped pulses to achieve the required selective n inversions. Other band selective shaped pulses have been developed for a more uniform excitation profile [93]. In its original implementation, fsREDOR was used to extract the intemuclear distances of several model crystalline compounds [92], In the past few years, this technique has proven to be very useful for the study of amyloid fibrils as well. For the Ure2p10 39 fibril samples containing 13C and 15N uniformly... 

Alternatively, a fiber can be one member of a group or aggregate, as a fibril is one part of a fiber. Spherulites (Fig. 1. IH), fan-shaped fibrous crusts or rosettes, and the veins depicted in Fig. 1.1A are examples of aggregates created when many crystalline fibers grow in close proximity. During fibrous growth, lateral interference may produce planar but irregular bound-... 

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