COATED FIBRE

Nassehi, V., Kinsella, M. and Mascia, 1.., 1993b. Finite element modelling of the stress distribution in polymer composites with coated fibre interlayers. J. Compos. Mater. 27, 195-214. 

Figure 11.15 Cation-exchange mia O-LC analysis of a mixture of model proteins (a) the original sample consisting of myoglobin (M), cytochrome C (C) and lysozyme (L) (b) and (c) proteins adsorbed on to and then released from the polyaaylic acid coated fibre with exti ac-tion times of 5 and 240 s, respectively. Reprinted from Journal of Microcolumn Separations, 8, J.-L. Liao et al., Solid phase mia O exti action of biopolymers, exemplified with adsorption of basic proteins onto a fiber coated with polyaaylic acid, pp. 1-4, 1996, with permission from Jolm Wiley Sons, New York.

HPLC solvents (PDMS-coated fibres are incompatible with hexane). PDMS fibres are more selective towards nonpolar compounds and polyacrylate fibres towards polar compounds such as acids, alcohols, phenols and aldehydes. Another feature of SPME fibre selectivity is discrimination towards high-MW volatiles. SPME has successfully been applied to the analysis of both polar and nonpolar analytes from solid, liquid or gas phases. Li and Weber [533] have addressed the issue of selectivity in SPME. 

Zalvidea, D., Diez, A., Cruz, J.L. and Andres, M.V., A wavelength multiplexed hydrogen sensor based on a palladium-coated fibre taper and a Bragg grating, Electron, 40, 301, 2004. 

Hua et al. [595] have described an automated flow system for the constant-current reduction of uranium (VI) onto a mercury film-coated fibre electrode. Interference from iron (III) was eliminated by addition of sulfite. The results obtained for uranium (VI) in two reference seawater samples, NASS-1 and CASS-1, were 2.90 and 2.68 g/1, with standard deviations of 0.57 and 0.75 g/1, respectively. 

For films, sheets, tubes, wire and cable coatings, fibres, mass production of household requisites, bottle racks, bins, containers, pallets, tubes, prostheses, antifriction parts. .. 

This method is based on the partitioning of compounds between a sample and a coated fibre immersed in it [16-18]. The volatiles and other compounds are first adsorbed onto the fibre immersed in a liquid sample, an extract, or in the headspace above a sample for a certain period of time. After adsorption is complete, the compounds are thermally desorbed into a GC injector block for further analysis. Particularly in food applications, headspace SPME is preferred to avoid possible contamination of the headspace system by non-volatile food components [16]. 

Optics und hence guided wave velocity can be controlled with great precision acceptable attenuation loss. Possible uses in conventional optics and optical data storage, pboiochromic and ablative systems. Optical sensors e g. based on coated fibres. 

Modification of textile fibres to obtain gold-coated fibres... 

Synthetic biodegradable polyesters are used mainly as specialty materials for paper coating, fibres, and garbage bags and sacks. They are also showing up in thermoformed packaging as functional adjuncts to lower-cost biodegradable materials. 

Nodax has the benefit of degradation in septic systems, which offer possibilities for application in feminine hygiene products such as wipes and tampon applicators. These flushable products may exist in the form of paper coatings, fibres, films and foams. 

Fisher CE, Brown DM, Shae J, et al. 1998. Respirable fibres Surfactant coated fibres release more Fe3+ than native fibres at both pH 4.5 and 7.2. Arm Occup Hyg 42 337-345. 

The effect of coating thickness on the response time of the sensor was also evaluated. The time dependent response of a sensor coated with a 100 micron layer and that of a sensor coated with a 200 micron layer to a 10 ppm PMP solution at pH = 13 was measured. The fibre with a 200 micron coating reached a maximum response within 14 min. The response time of the 100 micron coated fibre was decreased to 8 min. For an on-line monitor, the time for initial response is the most important factor. Using pH = 13, a distinct response occurred within 1 min. 

A solid-phase microextraction process involves two steps, namely partitioning of the analytes between the coating and the sample, and desorption of the concentrated species into an analytical instrument. In the first step, the coated fibre is exposed and the target analytes are extracted from the sample matrix into the coating. In the second step, the fibre with the concentrated analytes is transferred to an instrument for desorption. A third, clean-up step can also be incorporated by using selective solvents, as in SPE. 

Fig. 7.15. Coupled SFE-SFC system with dual detector for the total and individual analysis of a coating fibre extract. (Reproduced with permission of Springer-Verlag.)...

It must be noted that the chromatographic method leads to values of Ys that are more precise than the ones obtained by wetting, although they agree well. TTie untreated and oxidized carbon fibres have high values of Ys whereas the coated fibres exhibit somewhat lower values, close to the ones for the polymer matrices. 

The value for the coated fibre is in agreement with the fact that the coating is usually made of either epoxy or polyester. 

Specific interactions. As demonstrated in the previous section, the tensiometric method also provides values of the surface polarity of the solids (Table I). The surface polarity of the untreated fibre is low whereas that of the oxidized or coated fibres is high. Furthermore, Ys is different for the two matrices. 

Figure 5 Determination of 7 and 7 of the coated fibre 3 by the wetting technique.

The fibre yam is fed and collected by two spools which should have a large diameter to prevent damage to the coated fibres. After a fibre yam is drawn from the feeding spool it is uniformly spread by Teflon pulleys with the help of tension indicators. The movement of the fibre yam is driven by a motor connected with the collecting spool at the upper position. In order to minimise and eliminate oxygen contamination from the air the reactor and two spools are placed within an enclosure which can be evacuated. In the system the heating temperature can reach a maximum temperature of 2000°C and the pressure is evacuated to 0.05 to 0.1 Torr during the CVD process by vacuum pumps. 

As the deposition advances the fibre becomes thicker and thicker. The radius of the coated fibre is then expressed as... 

The partitioning of analytes between an aqueous sample and a stationary phase is the main principle of operation of SPME. A mathematical relationship for the dynamics of the absorption process was developed by Louch et al. [3], In this situation, the amount of analyte absorbed by the silica-coated fibre at equilibrium is directly related to its concentration in the sample, as follows ... 

Bleaches are used in the chemical processing of textiles, paper pulp, oils, foodstuffs, coatings, fibres, and other materials to remove or decolourize impurities. They are also used as cleaners and disinfectants. There are two broad classes of bleach, the first of which are the oxidizing bleaches (those that contain chlorine or active oxygen) ... 

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