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Excessive soot concentration in the lubricant promotes excessive wear on timing chains. The relationship between chain wear and soot concentration, morphology, and nanostructure, however, remains inconclusive. In this work, a chain wear test rig is used to motor a 1.3 L diesel engine following the speed profile of a Worldwide Harmonized Light Vehicle Test Cycle (WLTC). The lubricant oil was loaded with 3% carbon black of known morphology. The chain length is measured at regular intervals of 20 WLTC cycles (i.e. 10 hours) and the wear is expressed as a percentage of total elongation. Oil samples were collected and analysed with the same frequency as the chain measurements. Carbon black morphology and nanostructure were investigated using Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM).

The determination of the hydrogen pressure equivalent to one amp hour of stored capacity has been conducted at various rates of charge and discharge and at different temperatures. Cell temperature control in this determination contrasts isothermal versus cold plate conditions. Selected regions of the hydrogen pressure plots are evaluated in terms of consistent cell pressure factors. Pressure factors determined on charge suggest a maximum coulombic efficiency of 96% to that obtained on discharge.

Hydrogen gas pressure has been utilized to determine state of charge, efficiency on charge, establish voltage/current relationships and to derive an equivalent cell level DC resistance. In response to a fixed measurement cycle, the studied cell design is able to store more charge at lower temperatures. This is accomplished by more efficient charging to a higher cell voltage. However, as higher states of charge (pressure) are attained, the discharge profile depresses. This corresponds to an increased cell DC resistance. Furthermore, this cell level DC resistance increases with the depth of discharge and the rate of this increase is greater at lower temperatures.