Near-term applications

The advances in hydrogen research are mostly at an early stage with further progress in nnderstanding and in material performance expected in the near term. Applications to indnstrial products are expected to follow. 

DMFCs have potential near-term applications mainly in the portable power source market, as they are smaller, lighter, simpler, and cleaner than conventional batteries. Liquid methanol is consumed directly in a DMFC, which implies a higher energy density of the fuel cell system. But the power densities achievable with state-of-the-art DMFCs are still smaller in comparison... 

Effective utilization of biomass for value-added chemical product synthesis will require development of new applications of important unit operations. Carbohydrate recovery from the biomass is the key near-term application for production of commodity chemicals. Protein recovery will continue to have an important niche market in tlie purified form as food and a larger low-value market in the crude form as animal feed. Important processing information for carbohydrate depolymerization can be found in the literature from biochemical conversion of biomass. New process applications of separation technologies are just now being developed and refined for use with biomass-derived carbohydrate and protein streams. The use of an aqueous processing environment for carbohydrates will require careful consideration of the differences that type of environment entails, such as the effect on catalyst formulations. 

Particularly promising near-term applications of nanomaterials that may yield order-of-magnitude improvements over current generation technologies include (1) membrane separations, (2) catalysis, (3) contaminant sensing, (4) energy production and storage, and (5) contaminant immobilization. 

Three-phase catalytic membrane reactor systems, in our opinion, show significant promise, for near term application to hydrogenation reactions for fine chemicals synthesis. These reactions generally require mild operating conditions which will place less stringent requirements on the available and future commercial membranes. 

The possibilities of extremely rapid processing and the production of useful new products stimulates interest in the development of plasma reactors for the chemical process industries. Categories for potential near-term application of the discharge reactor include (8) ... 

Continue work with industrial partners to investigate near-term applications for the biological water gas shift process. 

Recently, bottom-up processes utilizing self-assembly have been developed that could become the next generation of nanostructure processing, as they overcome the problems listed above. In particular, self-assembling copolymers have attracted much attention as potential nanostructuring agents over the past decades and are still subject to ongoing research [3]. The most important near-term application is their use in the microelectronics industry as etch mask with pattern dimensions far below the optical diffraction limit [4]. 

Even though exhaust nozzles in aircraft engines represent a lower temperature, near-term application, the requirements for successful implementation are demanding because unprotected exposure to the atmosphere results in ingress/egress of atmospheric moisture (the same problem that plagued the early deployment of PMCs). The presence of matrix cracks in CMCs makes moisture flow possible. In military aircraft, there is an added requirement for low observability (e.g., low dielectric constant). 

Bond [23] and Poirier [24] have presented valuable data and analyses of steam drying of handsheets in static laboratory test rigs. No pilot-scale data exist at this time on steam drying of paper or tissue. Application to tissue drying (impingement and through drying) appears to be the more imminent industrial-scale operation. Another potential near-term application is as a booster dryer to increase the productivity of a dryer-limited mill. 

DMFCs have potential near-term applications mainly in the portable power source market, as they are smaller, lighter, simpler, and cleaner than conventional batteries. Liquid methanol is consumed directly in a DMFC, which implies a higher energy density of the fuel cell system. But the power densities achievable with state-of-the-art DMFCs are still very small in comparison to hydrogen-fuelled PEMFCs. One of the major problems lies in the use of liquid methanol solution on the anode of the DMFC, which, on the one hand, keeps the ionomeric membrane water saturated (and thus no humidification is needed) but, on the other hand, does not keep fuel (methanol or any other organic fuel, e.g., formic acid, ethanol) and water from permeating to the cathode side, since the basic PFSA membranes are permeable to both methanol and water. - The fuel and water crossover from anode to cathode hampers the performance of the air cathode. 

At present, most researchers hold more realistic views of the promise and difficulties in the development of fuel cells, as well as in the development of electrocatalysis. We have concluded in Section 24.5 that an important near-term application is in portable power supply. This is a realistic expectation. It is based on need and on available solutions. 

Stryer, L. Biochemistry W.H. Freeman and Company San Francisco, 1981. Wyman, CJE. Goodman, B.J. Near Term Application of Biotechnology to Fuel Ethanol Production from Lignocellulosic Biomass NIST GCR 93-63 U.S. Department of Commerce Washington, D.C., 1993. 

Because of the anion complexation observed in the solid state, it was proposed that cyclo[8]pyrrole could function as an anion extractant, specifically for sulfate. Sulfate receptors that can act as extractants of this ion are highly desirable because sulfate is a problematic species in the vitrification process that is proposed for the disposal of certain radioactive wastes. The original reported short-chained forms of cyclo[8]pyrrole presented solubility issues, but a newer derivative, octamethyl-octaundecylcyclo[8]pyrrole, 2b, originally developed as a precursor for liquid crystals, proved to be amenable to extraction studies. It was found that 2b was able to selectively extract sulfate in the presence of high levels of nitrate. This cyclo[8]pyrrole was thus able to overcome the so-called Hofmeister bias or the inherent propensity for nitrate to partition before sulfate. While the kinetics are slow—reducing utility in the context of near-term applications—this is the first example where this level of selectivity is seen in a sulfate versus nitrate extraction experiment. ... 

McLean, C., Mustafl, S., Walls, L., Pitchford, B., Wollen, M., Schmidt, J., 2011. Simple, robust cryogenic propellant depot for near term applications. In IEEE-2011-1044. 

As structural ceramics find more applications in high temperature systems, oxidation and corrosion at high temperatures becomes an important field of study. In this chapter, the critical issues in this field have been surveyed. Ceramics have been classified according to the type of protective oxide they form. These include silica formers, alumina formers, boria formers, and transition metal oxide formers. Most of the literature covers silica formers since there are a number of near-term applications for these materials. Basic oxidation mechanisms, water vapor interactions, volatilization routes, and salt-induced corrosion were discussed for these materials. Less information is available on alumina-forming ceramics. However the rapid oxidation rate in water vapor appears to be a major problem. Boria formers show rapid oxidation rates due to the formation of a liquid oxide film and are volatile in the presence of water vapor due to highly stable Hx-By-Oz(g) species formation. Transition metal carbides and nitrides also show rapid oxidation rates due to rapid transport in the oxide scale and cracking of that scale. 

With continuous developments in the synthesis and production of CNTs, CNT/polymer composite materials are a near-term application and will see innovations that take full advantage of their special properties. 

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