The character of residential cooktop fires

A series of experiments was conducted to investigate the global preignition and combustion characteristics of corn oil heated in 9.7 to 26 cm diameter pans by a residential electric-coil element cooktop. For comparison, torch-ignited gasoline, heptane, and corn oil experiments were conducted in the same configuration except without the heating element energized. Heating oil on a typical electric cooktop leads to vaporization and generation of an aerosol cloud followed by autoignition. The evolution of the light-extinction coefficient before autoignition is measured and shown to be related to the pan diameter and initial fuel mass. Continued heating leads to enhanced vaporization of the burning oil and growing fires with the peak heat release rate, radiative heat flux, radiative fraction, and peak flame height larger than the gasoline fires regardless of pan diameter. CO and soot yields, and the CO/CO2 ratio are measured to decrease with pan diameter.

A metamaterial based dual-resonant coil element for combined sodium/hydrogen MRI at 7 Tesla

A single coil element based on a composite right/left-handed (CRLH) metamaterial transmission line for combined sodium and hydrogen MRI is presented. It provides the particular feature of equal quarter-wavelength current and electromagnetic (EM) field distributions at the two distinct Larmor frequencies of