Enemy or foe is an individual or a group that is seen as forcefully adverse or threatening. The concept of an enemy has been observed to be basic for both individuals and communities.
A diffractometer (pronunciation: di-frak-'tÃ¤-m&-t&r) is a measuring instrument for analyzing the structure of a material from the scattering pattern produced when a beam of radiation or particles (such as X-rays or neutrons) interacts with it. Principle
1 Note: Salt refractometers are used to measure sodium chloride dissolved in water. 2  Seawater refractometers are used to measure the mixture of salts typically found in seawater or saltwater aquariums. 3  Using the wrong one may result in a reading approximately 5% off, which may be acceptable for non-laboratory purposes. Note: Salt refractometers are used to measure sodium chloride dissolved in water. 2  Seawater refractometers are used to measure the mixture of salts typically found in seawater or saltwater aquariums. 3  Using the wrong one may result in a reading approximately 5% off, which may be acceptable for non-laboratory purposes.