A model for performance of the cathode side of a direct methanol fuel cell at small currents is developed.
The results show that, at small currents, constant property model developed by this work can predict accurately the dynamic characteristics, however, with the increase in current, the temperature-dependence of properties have more and more remarkable effect on the dynamic temperature variations, especially for high cooling loads.
Instead of sweep air, pure oxygen production is preferred only at small current density, which delivers the highest system efficiency but the lowest methane yield.
The results reveal that although 3D-O2-Cat-2 can retain their catalytic activity at small current densities (Supplementary Fig. 20), this material undergoes serious deactivation over 50 h at large current densities (Fig. 5c).
A correction for the contribution of the oxygen layer formation to the anodic charge has to be applied in the determination of the COad coverage even at small current densities.
The main one is the long-time operational stability: most of recently developed oxygen evolution electrodes are shown to only work well for a few to several tens of hours at small current densities (e.g., 10 mA cm−2), and very few can last for several hundreds of hours6, 8.
With the increase in temperature difference, the optimal N increases at smaller currents of I ≤ 1.0 A, however, it is almost invariable at larger currents of I ≥ 1.5 A.
Thanks to the reduced density of states, the QD medium always achieves early gain saturation at smaller current density compared with its bulk and quantum well counterparts, which means that the differential gain of this medium decreases rapidly when increasing the injection current, as shown in Figure 4.
Due to a smaller cavity-gain detuning at 85 °C for small currents, the modulation efficiency here is higher.
It is found that the AC loss in the strip superconductor of the ripple current becomes larger than that without DC current at small ripple current amplitude, since the penetration depth of magnetic field becomes large.
As seen in Figure 6A, in WT-hSGLT3 expressing oocytes there is a current when the pH is lowered from 6 to 5, and 10 mM glucose induces small currents at pH 6, but much larger currents at pH 5. It is possible that small currents mediated by WT-hSGLT3 on standard plates (pH 6) result in repulsion and that larger currents that occur on pH 5 plates result in attraction.
