Long-line fibers

Pache JC, Janssen YMW, Walsh ES, et al. 1998. Increased epidermal growth factor-receptor protein in a human mesothelial cell line in response to long asbestos fibers. Am J Pathol 152 333-340. 

Figure 6-10. Results of statistical analysis of the weight (mg) of a 15.2 cm long coated fiber. A multiple regression model limited to linear terms for temperature, MTS flow rate, and hydrogen flow rate was used to predict the fiber weight, (a) Predicted contour lines show the strong effect of MTS flow rate and temperature on fiber weight for a constant H2 flow rate of 2.5 L/min. (b) Plot of observed vs. predicted fiber weight shows reasonably good agreement.

CASE 8.6 DIRECT IN-LINE COMPOUNDING OF LONG-GLASS-FIBER PP [8-4, 8-5]... 

The major elements required for fiber-optics transmission include long flexible fibers made of transparent materials such as glass, plastic, or plastic-clad silica a light-transmittal source such as a laser of light-emitting diode (LED) cables or rods lined with a reflective core medium to direct light and a receiver to capture the signal. Many systems... 

Vetron composites of polypropylene reinforced with up to 75 percent Twintex long glass fibers (LGF) are produced by LNP Engineering, a business unit of G.E. Plastics, for exterior and underhood applications, and RTP compounds a line of LGF reinforced com-... 

With reference to Fig. 9-1, we assume that a diffuse source excites a sufficiently long straight fiber to enable the spatial steady state to be reached at the beginning of the bend. The analysis of ray paths around the bend depends on the profile. If the profile is a step, the trajectory is a straight line between successive reflections, involving the solution of cubic and quartic polynomial equations, whereas, if the profile is a clad parabola, a paraxial approximation is used [2]. 

In the early 1990s, there were more than 9 x 10 km of fiber-optical telecommunication links in practical use in the United States. In addition, many other countries, notably Canada, Japan, and western Europe, have installed extensive fiber-optic communication systems. There are several transoceanic fiber-based telephone cables. Fibers are in use for intracity telephone links, where bulky copper [7440-50-8] wine is replaced by thin optical fibers. This allows crowded conduits in large cities to carry more messages than if copper wine were used. Fiber optics are used for intercity long-haul telephone links, for interoffice tmnk lines, and have replaced many microwave communication links. 

However, optical fiber communications are not useful only for long-distance communication links. Fiber-optic data links are also used in a variety of short-distance systems, for example in computer—computer links and for internal communications on ships and aircraft. Figure 16 shows some possible appHcations for fiber-optic communications, with respect to length and bit rate. The common carrier appHcations, like telephone links. He to the upper right of the dashed line labeled 100 MHzkm. However, a wide variety of other lower performance appHcations, illustrated to the lower left of the dashed line, are in use or under development. 

At one extreme, one has the structural models of perfect crystals, which have long-range positional order for all the atoms (apart thermal motion). A diffraction experiment on a set of such crystals oriented in one direction (corresponding, in most real cases of polymeric materials, to an oriented fiber) would result in a pattern of sharp reflections organized in layer lines. 

In the first case, there is only partial instead of complete long-range three-dimensional order. Fiber spectrum features are diffuse haloes (besides sharp reflections) on the layer lines. 

As an example of the second case, we may have conformationally disordered chains, but long-range order in the positions of the chain axes (condis crystals [5]). Fiber spectrum features are the occurrence of sharp reflections on the equator only and diffuse reflections on the other layer lines. 

The third category, shown in Fig. 2d, results when all of the long molecules or microcrystallites are aligned along the fiber axis, but they aggregate with little lateral ordering. This assembly, called an oriented fiber, diffracts to produce a series of layer lines that are perpendicular to the fiber axis. The intensity is nonuni-... 

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