Cell reversal transportation applications

MEAs in PEM fuel cells require sufficient lifetimes for applications in transportation and/or stationary power generation. During lifetime testing, the PEMFC performance should be stable and the operation behavior reliable. However, PEM fuel cells at present cannot guarantee lifetimes of 5,000 hours for mobile or transportation applications and 40,000 hours for stationary applications. The durability of the fuel cell, strictly related to the lifetime, is defined as the ability of a cell to resist permanent change in performance over time. Normally, lifetime degradation is not a catastrophic failure. However, it does indicate that the MEA degradation is not recoverable or reversible. 

Niacin (vitamin B3) has broad applications in the treatment of lipid disorders when used at higher doses than those used as a nutritional supplement. Niacin inhibits fatty acid release from adipose tissue and inhibits fatty acid and triglyceride production in liver cells. This results in an increased intracellular degradation of apolipoprotein B, and in turn, a reduction in the number of VLDL particles secreted (Fig. 9-4). The lower VLDL levels and the lower triglyceride content in these particles leads to an overall reduction in LDL cholesterol as well as a decrease in the number of small, dense LDL particles. Niacin also reduces the uptake of HDL-apolipoprotein A1 particles and increases uptake of cholesterol esters by the liver, thus improving the efficiency of reverse cholesterol transport between HDL particles and vascular tissue (Fig. 9-4). Niacin is indicated for patients with elevated triglycerides, low HDL cholesterol, and elevated LDL cholesterol.3... 

Stack, and a potential difference sufficient to force current through the stack is applied between the two electrodes placed at each end of the stack. For current to pass between the electrodes, ions must be transported through each of the membranes. By arranging the feeds to the various intermembrane compartments, it is possible to force ionic salts to pass from the dilute stream to the concentrated stream. In this way, a salt can also be split into its acid and base components. By combination of several cell pairs that comprise an anion- and a cation-selective membrane sheets in parallel, a stream concentrated in the original salts may be prepared. This configuration is the common method for industrial use, in which electrodialysis gives broadly the same result as reverse osmosis and has found very similar applications to general water treatment. 

---