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Instead, the Rydberg constant is inferred from measurements of atomic transition frequencies in three different atoms (hydrogen, deuterium, and antiprotonic helium). Detailed theoretical calculations in the framework of quantum electrodynamics are used to account for the effects of finite nuclear mass, fine structure, hyperfine splitting, and ...
Rydberg constant: 10 973 731.568 157 ... and is strongly dependent on how those units are defined. For example, the atomic mass constant is exactly known ...
Since one in about every 6,400 hydrogen atoms is deuterium, a 50-kilogram (110 lb) human containing 32 kilograms (71 lb) of body water would normally contain enough deuterium (about 1.1 grams or 0.039 ounces) to make 5.5 grams (0.19 oz) of pure heavy water, so roughly this dose is required to double the amount of deuterium in the body.
Thus, deuterium accounts for about 0.0156% by number (0.0312% by mass) of all hydrogen in the ocean: 4.85 × 10 13 tonnes of deuterium – mainly as HOD (or 1 HO 2 H or 1 H 2 HO) and only rarely as D 2 O (or 2 H 2 O) (deuterium oxide, also known as heavy water) – in 1.4 × 10 18 tonnes of water.
An individual’s total body water can be determined using flowing-afterglow mass spectrometry (FA-MS) to measure the abundance of deuterium in breath samples. A known dose of deuterated water (heavy water, D 2 O) is ingested and allowed to equilibrate within the body water.
atomic mass constant: m u = 1.660 539 068 92 (52) × 10 −27 kg: u r (m u) = 3.1 × 10 −10 [68] muc2: atomic mass constant energy equivalent m u c 2 = 1.492 418 087 68 (46) × 10 −10 J: u r (m u c 2) = 3.1 × 10 −10 [69] muc2_MeV: atomic mass constant energy equivalent in MeV: m u c 2 = 931.494 103 72 (29) MeV: u r (m u c 2) = 3. ...
Parts-per-million cube of relative abundance by mass of elements in an average adult human body down to 1 ppm. About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium ...
Water 220.64 bar, 373.8 °C [citation needed] [clarification needed] 1.968: 0.708: Kinetic energy penetrator [clarification needed] 1.9: 30: battery, Lithium–Sulfur [15] 1.80 [16] 1.26: battery, Fluoride-ion [citation needed] 1.7: 2.8: battery, Hydrogen closed cycle H fuel cell [17] 1.62: Hydrazine decomposition (as monopropellant) 1.6: 1.6