Search results
Results from the WOW.Com Content Network
Deuterium-depleted water has less deuterium (2 H) than occurs in nature at sea level. [1] Deuterium is a naturally-occurring, stable (non-radioactive) isotope of hydrogen with a nucleus consisting of one proton and one neutron. A nucleus of normal hydrogen (protium, 1 H) consists of one proton only, and no neutron.
Semiheavy water is the result of replacing one of the protium (normal hydrogen, 1 H) in normal water with deuterium (2 H; or less correctly, [1] D). [2] It exists whenever there is water with 1 H and 2 H in the mix. This is because hydrogen atoms (1,2 H) are rapidly exchanged between water molecules.
Thus heavy water as defined by the Gold Book includes semiheavy water (hydrogen-deuterium oxide, HDO) and other mixtures of D 2 O, H 2 O, and HDO in which the proportion of deuterium is greater than usual. For instance, the heavy water used in CANDU reactors is a highly enriched water mixture that is mostly deuterium oxide D
For water, the condensed phase is more enriched while the vapor is more depleted. For example, rain condensing from a cloud, is heavier than the vapor starting point. Generally, the large variations in deuterium concentration in water are from fractionations between liquid, vapor, and solid reservoirs.
Deuterium occurs in trace amounts naturally as deuterium gas (2 H 2 or D 2), but most deuterium atoms in the Universe are bonded with 1 H to form a gas called hydrogen deuteride (HD or 1 H 2 H). [12] Similarly, natural water contains deuterated molecules, almost all as semiheavy water HDO with only one deuterium.
An example is water, whose hydrogen-related isotopologues are: "light water" (HOH or H 2 O), "semi-heavy water" with the deuterium isotope in equal proportion to protium (HDO or 1 H 2 HO), "heavy water" with two deuterium atoms (D 2 O or 2 H 2 O); and "super-heavy water" or tritiated water (T 2 O or 3 H 2 O, as well as HTO [1 H 3 HO] and DTO [2 ...
In 1964, the concept of deuterium excess d (d = δ 2 H - 8δ 18 O) [3] was proposed. Later, a parameter of deuterium excess as a function of humidity has been established, as such the isotopic composition in local meteoric water can be applied to trace local relative humidity, [10] study local climate and used as a tracer of climate change. [6]
Normal water is fed to the hot tower where deuterium transfer takes place from the liquid water to the hydrogen sulfide gas. In cascade systems, the same water is used for both inputs. The mechanism for this is the difference in the equilibrium constant; in the cold tower, deuterium concentration in the hydrogen sulfide is lowered, and the ...