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 the ratio of density of a substance compared to the density of fresh water at 4Â°C (39Â° F). At this temperature the density of water is at its greatest value and equal 1 g/mL. Since specific gravity is a ratio, so it has no units.An object will float in water if its density is less than the density of water and sink if its density is greater that that of water. Similarly, an object with specific gravity less than 1 will float and those with a specific gravity greater than one will sink.pecific gravity is the ratio of density of a substance compared to the density of fresh water at 4Â°C (39Â° F). At this temperature the density of water is at its greatest value and equal 1 g/mL. Since specific gravity is a ratio, so it has no units.