Heartburn is often triggered by foods. This is because certain substances irritate the esophagus or weaken the lower esophageal sphincter (LES), which prevents the backward flow of stomach contents that causes reflux. Triggers can include: 1  alcohol. 2  caffeinated products, such as coffee, soda, and tea. 3  chocolate. 4  citrus fruits. 5  garlic. 6  fatty foods. 7  onions.
Testing specific gravity of fuel. Specific gravity is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.
Specific gravity has no units because itâs a ratio of density divided by density, so all units cancel out. Therefore, the specific gravity of gold is simply 19.3. Anything with a density greater than 1,000 sinks in pure water at 4 degrees Celsius, and anything with a density less than 1,000 floats. As youâd expect, gold, with a density of 19,300 kg/m3, sinks. Ice, on the other hand, with a density of 917 kg/m3, floats.