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.
Because the density is directly related to the mass, the specific gravity can also be determined from the ratios of the mass of the object to the mass of water, or the weight of the object to the weight of water. The specific gravity has no units and its value determines if the object will float or sink in water.esson Summary. The specific gravity of an object is the ratio between the density of an object to a reference object. Usually, our reference object is water, which has a density of 1 g/mL or 1 g/cm^3.