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 is defined as the comparison of a liquidâs weight with the weight of an equal volume of water. In other words it is the weight per unit of volume of the slip. In metric it is simple: water weighs one gram per cc (ccs and milliliters are the same). If a slurry weighs 1.8 grams per cc, then it has a specific gravity of 1.8; it is 1.8 times heavier than water.