Niche Applications

In Section 13.2, we mentioned that whisker reinforcement aids in increasing the flexural strength and fracture toughness of CBPCs. Acicular crystals of wollastonite act like whiskers. In this section, the effect of hber reinforcement is discussed. 

These studies by Wagh and coworkers with glass hbers are only an indication of how hber-reinforced composites may be developed using CBPCs. Because of neutrality of the CBPC matrix and its formation at room temperature, a range of hbers may be added in the matrix that include natural hber (such as wood, cellulose, and cotton) and artihcial hbers (such as nylon). The greatest potential is in wood composites. Unlike the case of glass hbers, a bond should form between the natural hber surface and the CBPC matrix. This bond should produce superior hber-reinforced composites (cements). These areas are shll open for research, and hardly any work has been reported in the literature. 

Wide-ranging applications of CBPCs are possible, because, as mentioned in the preceding section, CBPC matrix composites can be made with very high loading of either waste 

Flexural strength as a function of glass fibers in ash containing Ceramicrete. 

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In summary, heat-driven cycles for cooling or heat pumping can have energy saving and environmental benefits. There are also niche applications in developing countries or remote areas. Adsorption cycles using active carbons are one of a number of approaches that might be economically viable. 

In certain niche applications, aliphatic isocyanates, such as isophorone diisocyanate (IPDI), hexamethylene diisoeyanate (HDI), methylene 4,4 -biscyclo-hexylisocyanate (H12MDI), and polymeric versions of these diisocyanates, are used, e.g., in instances where light stability or reduced reactivity is needed. These isocyanates usually cost more than the aromatic diisocyanates. Thus, they are used in adhesive areas that can Justify the higher costs. 

There are a variety of specialty dryers tailored to different process applications. Airknife drying is one example of a simple system that has found numerous niche applications. Designs are engineered profile plenum assemblies in lengths typically... 

The major uses of lead in the UK are in batteries, and in sheet and pipe of which the vast majority is sheet for building purposes. These applications account for about one third each of lead used. This situation is unique, since in all other countries batteries account for most of the lead market. A small but very important application is sheet and pipe for the chemical industry. Lead is no longer installed for water services. Lead cable sheathing which accounts for 5% is in general decline, but is valued in niche applications such as on oil rigs where resistance to hydrocarbons is important. The use of lead for anodes accounts for a very small tonnage, but is still of great importance to the industries which use them. 

Although it is attractive to directly convert chemical energy to electricity, PEM fuel cells face significant practical obstacles. Expensive heavy metals like platinum are typically used as catalysts to reduce energy barriers associated with the half-cell reactions. PEM fuel cells also cannot use practical hydrocarbon fuels like diesel without complicated preprocessing steps. Those significantly increase the complexity of the overall system. At this time, it appears likely that PEM fuel cells will be confined to niche applications where high cost and special fuel requirements are tolerable. 

Poly(l,4-cyclohexylenedimethylene terephthalate) (PCT) finds some niche applications in the packaging market as amorphous, clear, extrusion, or injectionmolding material for films and bottles. 

Whilst the acids and many of their derivatives currently find niche applications in the market sectors identified above, factors related to price, volume of supply and consistency have all limited commercial viability. In the longer term, reduced costs and improved consistency through improved growing and harvesting techniques, coupled with an increased requirement for biodegradability, will increase demand for fatty acids. 

Natural fatty aeid-based lubricants fall between mineral oil and the synthetic acid diester lubricants in both performance and price (Figure 6.8) as such they find niche applications. Compared to mineral oils vegetable oil-based lubricants offer several advantages, notably ... 

Like many of the topics discussed in this book, photochemical reactions are most likely to be used in niche applications for commercial and environmental reasons. Unless there is a major breakthrough in reactor and lamp design, widespread use of this technology is unlikely. Perhaps the best hope of producing high-intensity monochromatic sources of radiation rests with lasers, but currently equipment costs are too high to justify their use for commercial chemical production. 

The large molecular size and ambient operation of enzymes means that they are likely to be more suited to niche applications rather than to high-power devices, but there are important lessons to be leamt from biological catalysis that occurs in conditions under which conventional metal catalysts would fail. Development of synthetic catalysts inspired by the chemistry (although not necessarily the stmctures) of enzyme active sites may lead to future catalysts with new and improved properties. 

GARField has found a niche application area in the characterization of drying and film forming from aqueous dispersions and in skin-care. As a bench-top perma-... 

From the characteristics of the methods, it would appear that FD-MS can profitably be applied to poly-mer/additive dissolutions (without precipitation of the polymer or separation of the additive components). The FD approach was considered to be too difficult and fraught with inherent complications to be of routine use in the characterisation of anionic surfactants. The technique does, however, have a niche application in the area of nonpolar compound classes such as hydrocarbons and lubricants, compounds which are difficult to study using other mass-spectrometry ionisation techniques. 

Applications Sector instruments are applied for niche applications such as high-resolution measurements and fundamental ion chemistry studies. Magnetic sector mass spectrometers remain the instrument of choice in areas of target compound trace analysis, accurate mass measurement and isotope ratio measurement. 

The ideal interface is rare. Table 7.3 lists the qualities required for an ideal interface from a chromatographic point of view [3]. Nowadays, hyphenation goes a long way towards total analysis systems (e.g. HPLC-UV-NMR-MS), especially in the pharmaceutical industry. Such magic-wand systems are by no means a panacea for all analytical problems they are more likely to be confined to niche applications. Multihyphenation and multidetector monitoring set their own... 

Linking TLC with a tandem instrument differs from combining GC or LC with an appropriate spectrometer. Hyphenation of planar chromatographic techniques represents a niche application compared to HPLC-based methods. Due to the nature of the development process in TLC, the combination is often considered as an off-line in situ procedure rather than a truly hyphenated system. True in-line TLC tandem systems are not actually possible, as the TLC separation must be developed before the spots can be monitored. It follows that all TLC tandem instruments operate as either fraction collectors or off-line monitoring devices. Various elaborate plate extraction procedures have been developed. In all cases, TLC serves as a cleanup method. 

A specific case of mobile sources, where nearly the same conventional system used for stationary sources (SCR-NH3) can be applied, regards the reduction of NO in the exhaust gas from marine engines and gas turbines. The first marine installation was in 1989 on a 37 000tdw deep-sea bulk carrier [61]. Many more installations exist today, but this still remains a niche application. 

Transistors have replaced amplifier valves in niche applications. The function of this element is to bind traces of oxygen in the vacuum tube. 

Generation of hydrogen from H2S using cadmium sulfide with waste products as sacrificial agents to avoid photocorrosion of the semiconductor is expected to grow as a niche application. 

The major potential application of active carbon fibers is as an adsorbent in environmental control, as outlined in the previous section. However, there is a number of smaller scale, niche applications that seem to be particularly suited to ACF. These emerging applications include the use of ACF in medicine [111 (see also 59,60),112], as capacitors [113-119] and vapor sensors [120], and in refrigeration [121]. The first two of these applications are summarized below. However, there are not many detailed, publicly-available sources describing any of these applications, partly for commercial reasons and partly because the technology is emerging, so any summary is necessarily limited in scope. 

In Section II.3 we have seen that a specific chemical species existing in a given physicochemical environment is characterized by specific values of 7) and T2, and that this fact is important both in the implementation of imaging pulse sequences to obtain quantitative information and in the modification of the pulse sequences to image selectively one species and/or phase within the sample. While exploitation of relaxation time contrast is not likely to become a routine approach for chemical mapping in reactors, there will be niche applications in which it will continue to have use—three of these are identified below. The limitations of the approach derive from that fact that the relaxation times characterizing a system will not only be influenced by chemical composition but also by temperature and the proximity of the molecules to a solid surface or interface. The three case studies illustrated below in which relaxation time contrast has been used with considerable success are (i) an... 

The oldest monoazo yellow pigment is Pigment Yellow 1, which continues to be produced and shipped on a large scale. Its discovery and introduction in 1910 was followed by the development of a variety of related pigments of this type, not all of which have turned into a commercial success. A few, such as pyrazolone-based Pigment Yellow 10, are still produced by some regional companies and are targeted for smaller niche applications. 

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