FP fiber

Figure 25. SEM of vessel pitting in hardwoods. (A) Vessel vessel pitting (VP) and vessel ray parenchyma pitting (RP) as seen from a transverse radial perspective in cottonwood (F = fibers). (B) Individual vessel element of cottonwood isolated by chemical pulping. (C) Isolated earlywood vessel element of white oak (FP = fiber vessel pitting).

Figure 2 (a) SEM photographs of cross-sections of PP fibers with a linear density of 27 dtex. (b) SEM photograph of hollow-additivated FP fibers with linear density of 30 dtex. 

Figure 31 Schematic illustration of RSNOM instrument constructed by the authors. E = exciting light, FP = fiber probe, DP = dithering piezo, DD = dither detection, LD = laser diode, PD = photodiode, SS = piezo XYZ scanning stage, TCO = transmission collection objective, RCO = reflection collection objective, M = mirror, RIMM = Raman imaging microprobe/microscope. The various movable mirrors allow the instrument to be operated in reflection or transmission modes and allow the operator to observe the probe-sample region through the collection optics this aids the coarse approach of the tip to the sample and helps optical alignment of the system.

In order to make a FPI chemical sensor, the FP cavity needs to be made accessible by the analyte molecules. One way to achieve this is to use a holey sleeve to host the cavity. Xiao et al.7 reported such a fiber FPI gas sensor formed by bonding two endface-polished fibers in a holey sleeve using epoxy. The holey sleeve allows gas to freely enter and leave the cavity. A resolution of 10 5 was estimated in monitoring the changes in the refractive index caused by varying the gas composition. However, the sensor assembly was complicated and required the use of epoxy. In addition, the various components used in sensor construction were made of different materials. As a result, the device had a strong dependence on temperature. 

Fig. 7.11 Fiber inline FP device in response to temperature change. Reprinted from Ref. 18 with permission. 2008 Optical Society of America...

The temperature dependence of the fabricated open cavity FP device was evaluated experimentally. The sensor was placed in a programmable electric tubular furnace. The temperature of the furnace was increased from room temperature to 1,100°C at a step of 50°C. The cavity length as a function of the temperature is plotted in Fig. 7.11, where it increased nearly linearly following the increase of temperature. The temperature sensitivity of the particular FP device under test was estimated to be 0.074 nm °C 1 based on the linear fit of the measurement data. The equivalent coefficient of thermal expansion (CTE) of the fiber FP device was 2.4x10 6oC. ... 

Table 1 summarizes a few properties of the resulting fibers used in studies on their metal ion adsorption abilities. Hereafter, bifucntional fibers derived from PPPE-c and PPPE-f are denoted by symbols FPS-c and FPS-f, respectively, and respective symbols FP-c and FP-f denote monofunctional... 

Figure 3. Time course for uptake of Pb(II) by FPS-c, FP-c, and CRP200. Resin or fibers 0.3 g solution 150 ml of 5 x 10-3 M lead nitrate solution temperature 30 oC.

Since the batchwise study clarified that the bifunctional fiber FPS-c adsorb Pb(II) more rapidly than monofunctional fiber FP-c, of interest is the... 

Figure 4. Breakthrough curves of Pb(II) in the adsorption of Pb(II) by FPS-f and FP-f packed columns. Column 1.5 ml of wet fiber (0.4 g in dry state), feeding solution 0.01 M lead nitrate. Flow rates in space velocity (h-1) are denoted on the figure.

As conclusion, bifunctional fibers having both phosphonic acid and sulfonic acid groups exhibit the characteristic metal ion selectivity and high breakthrough capacities in addition to the extremely fast adsorption rates. Studies on behavior of FPS-f in adsorption of other heavy metals like Fe(III) are now in progress. The bifunctional fiber developed in this work is attractive to application to the protection of the environment because of its extremely rapid adsorption rates and characteristic metal ion selectivity. 

Properties Fiber FP PRD-166 Saffil RF Saffil HA Safimax Fiberfrax Nextel 312 Nextel 440... 

At equilibrium, when the single fiber is immersed in the two liquids, the net increase in force is contributed by three different forces the apparent weight of liquid raised at the air-hydrocarbon-fiber interface, Fha, the apparent weight of liquid raised at the hydrocarbon-formamide-fiber interface, Ffh, and the buoyancy acting on the length of the fiber immersed, Fp, as seen in Fig. 4. When the diameter of the fiber is very small, the buoyancy contribution will be too small to be neglected (being of the order of 10-8N compared to the other two contributions, which have an order of 10 6N). 

Komorowski TE, Shepard B, Okland S, Carlson BM (1990) An electron microscopic study of local anesthetic-induced skeletal muscle fiber degeneration and regeneration in the monkey. J Orthop Res 8 495-503 Luduena FP, Hoppe JO, Coulston F, Drobeck HP (1960) The pharmacology and toxicology of mepivacaine, a new local anesthetic. Toxicol Appl Pharmacol 2 295-315 Okland S, Komorowski TE, Carlson BM (1989) Ultrastructure of mepivacaine-induced damage and regeneration of rat extraocular muscle. Invest Ophthalmol Vis Sci 30 1643-1651... 

---