Progress in Performance

Gamburzev, S., and Appleby, A. J. Recent progress in performance improvement of the proton exchange membrane fuel cell (PEMFC). Journal of Power Sources 2002 107 5-12. 

Gamburzev, S. and Appleby A.J. (2002) Recent Progress in Performance Improvement of Proton Exchange Membrane Fuel Cell (PEMFC), J. Power Sources, 107, 5-12. 

In case of a metal-supported cell concept, some new important challenges appear that must be overcome primarily concerning materials compatibility, materials processing and interaction, inter-diffusion and vaporisation of metallic alloy elements and finally hot corrosion/oxidation and high temperature creep of the metallic parts. Due to hot corrosion of the metallic layers in the cell the operation temperature has to be lowered to around 600-750 °C, which, on the other hand, leads to new challenges in the development of more active electrode materials. Recently, the METSOFC project has led to a significant progress in performance and durability of the metal-supported cells. 

Chromatographic Method. Progress in the development of chromatographic techniques (55), especially, in high performance Hquid chromatography, or hplc, is remarkable (56). Today, chiral separations are mainly carried out by three hplc methods chiral hplc columns, achiral hplc columns together with chiral mobile phases, and derivatization with optical reagents and separation on achiral columns. All three methods are usehil but none provides universal appHcation. 

Early [1, 2] it was reported about RP-HPLC the separation of amino derivatives of 3-chloro-l,4-naphtoquinone with methanol mobile phase. In some cases changing organic modificator in eluent leads to the progress in effectiveness of sepai ation. In present work the compaiison was performed for separation of some amino derivatives of 3-chloro-I,4-naphtoquinone by RP-HPLC with methanol and acetonitrile eluent. It has been shown that certain differences exist for vaiious derivatives mentioned above. 

The last two problems have been realized only recently, and additional progress in these research directions may be expected in the near future. At present it is clear that with the standard geometry approximation all time step limitations below 10 fs can be overcome rather easily. This time step increase gives a substantial net increase in performance compared to conventional MD. The possibility of larger step sizes now looks problematic, although it has been demonstrated for small molecules. Larger steps should be possible, however, with constraints beyond the standard geometry approximation. 

Progress in research and development in the wood-based industry and in the adhesive industry has shown many successes during the last decades. On the other hand, many industrial requirements still require considerable and important developments in this area. The main driving forces today are cheaper , quicker and more complex . The first two are caused by the heightened competition in the above-mentioned industries and the attempt to minimize costs while maintaining a certain level of product quality and performance. The key word more complex stands for new and specialized products and processes. Adhesives play a central role in wood-based panel production. The quality of bonding, and hence the properties of the wood-based panels, are determined mainly by the type and quality of the adhesive. Development in wood-based panels, therefore, is always linked to development in adhesives and resins. 

It is worth pointing out, however, that personality traits which do not provide people with adequate resources to maintain performance under stress, may compensate by supporting other activities during normal operations. For instance, "externals" may be more cautious than "internals" and take no chances to risk plant safety, while type A personalities may have a greater motivation to progress in their jobs and perfect their skills than type B personalities. Depending on the type of task, some personality traits will produce better performance than others. More research would be needed to develop a better understanding of the relationships between types of task and preferable personality styles. 

Billet, R., Development of Progress in the Design and Performance of Valve Trays, British Chem. Eng. Apr. (1969). 

Conducting interim progress reviews Interim progress reviews typically occur on a fixed time schedule, such as daily or weekly. They may also occur when some problem in performance is observed or at the completion of a significant step toward the accomplishment of the project. 

The enormous progress in the field of electroluminescent conjugated polymers has led to performances of oiganic light-emitting devices (LEDs) that are comparable and in some aspects superior to their inorganic counterparts 11). Quantum efficiencies in excess of 5% have been demonstrated [2] and show that a high fraction of the injected carriers in a polymeric electroluminescence (EL) device form electronic excitations which recombine radiatively. 

Many studies have been undertaken with a view to improving lithium anode performance to obtain a practical cell. This section will describe recent progress in the study of lithium-metal anodes and the cells. Sections 3.2 to 3.7 describe studies on the surface of uncycled lithium and of lithium coupled with electrolytes, methods for measuring the cycling efficiency of lithium, the morphology of deposited lithium, the mechanism of lithium deposition and dissolution, the amount of dead lithium, the improvement of cycling efficiency, and alternatives to the lithium-metal anode. Section 3.8 describes the safety of rechargeable lithium-metal cells. 

---