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Hydrogen isotopic composition

Cormie, A.B., Schwartz, H.P., Gray, J. (1994b). Determination of the hydrogen isotopic composition of bone collagen and correction for hydrogen exchange. Geochimica et Cosmochimica Acta, Vol. 58, pp. 365-375. [Pg.158]

Wassenaar, L.l. Hobson, K.A. (2000). Improved method for determining the stable-hydrogen isotopic composition (8D) of complex organic materials of environmental interest. Environmental Science and Technology, Vol. 34, pp. 2354-2360. [Pg.162]

Organic Mass Spectrometry in Art and Archaeology 14.9.7 The Hydrogen Isotopic Composition of Fatty Acids... [Pg.420]

The bulk hydrogen isotopic composition of amino acids has been shown to depend on animal trophic level (Birchall et al. 2005). Furthermore, compound-specific hydrogen isotopic analyses of amino acids may help elucidate the mechanism behind this enrichment, by determining the differences in 8D value between essential and non-essential amino acids, and may also provide a further palaeodietary indicator (e.g. Corr et al. 2005). However, amino acids are highly functional, with both amino and carboxyl extremely... [Pg.423]

Chikaraishi Y (2006) Carbon and hydrogen isotopic composition of sterols in natural marine brown and red macroalgae and associated shellfish. Org Geochem 37 428 136 Cimino G, Crispino A, Dimarzo V, Gavagnin M, Ros JD (1990) Oxytoxins, bioactive molecules produced by the marine opisthobranch mollusk Oxynoe olivacea from a diet-derived precursor. Experientia 46 767-770... [Pg.139]

The ranges of hydrogen isotope compositions of some geologically important reservoirs are given in Fig. 2.1. It is noteworthy that aU rocks on Earth have somewhat similar hydrogen isotope compositions, which is a characteristic feature of hydrogen, but not of the other elements. The reason for this overlap in isotope composition for rocks is likely due to the enormous amounts of water that have been cycled through the outer shell of the Earth. [Pg.36]

The D/H ratio of the sun is essentially zero all the primordial deuterium originally present has been converted into He dnring thermonuclear reactions. Analysis of primitive meteorites is the next best approach of estimating the hydrogen isotope composition of the solar system. [Pg.96]

EUer and Kitchen (2004) have re-evaluated the hydrogen isotope composition of water-rich carbonaceous chondrites by stepped-heating analysis of very small amounts of separated water-rich materials. Their special aim has been to deduce the origin of the water with which the meteorites have reacted. They observed a decrease in 5D with increasing extent of aqueous alteration from 0%c (least altered, most volatile rich) to —200%c (most altered, least volatile rich). [Pg.97]

In the marine environment oxygen and hydrogen isotope compositions of pore waters may be inherited from ocean water or inflnenced by diagenetic reactions in the sediment or nnderlying basement. Knowledge of the chemical composition of sedimentary pore waters has increased considerably since the beginning of the Deep-Sea-Drilling-Project. From numerous drill sites, similar depth-dependent trends in the isotopic composition have been observed. [Pg.146]

Atmospheric methane has a mean 5 C-value of around —47%c (Stevens 1988). Quay et al. (1999) presented global time series records between 1988 and 1995 on the carbon and hydrogen isotope composition of atmospheric methane. They measured spatial and temporal variation in and D with a slight emichment observed for the southern hemisphere (—47.2%c) relative to the northern hemisphere (—47.4%o). The mean 5D was —86 3%c with a 10%o depletion in the northern relative to the southern hemisphere. [Pg.173]

Hydrogen isotopic compositions, expressed as molar D/H ratios, of solar system bodies. The relatively low D/H values in the atmospheres of Jupiter and Saturn are similar to those in the early Sun, whereas D/H ratios for Uranus and Neptune are intermediate between the Jupiter-Saturn values and those of comets and chondrites. The Earth s oceans have D/H shown by the horizontal line. Mars values are from SNC meteorites. Modified from Righter et al. (2006) and Lunine (2004). [Pg.504]

Various isotope standards are used for reporting isotopic compositions the composition of each of the standards has been defined as 0 per mil. Oxygen and hydrogen isotopic compositions are commonly reported relative to standard mean ocean water (SMOW or V-SMOW) (17). [Pg.77]

Leaney, F.W., Osmond, C.B., Allison, G.B., and Ziegler, H. (1985) Hydrogen-isotope composition of leaf water in C3 and C4 plants its relationship to the hydrogen-isotope composition of dry matter. Planta 164, 215-220. [Pg.616]


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See also in sourсe #XX -- [ Pg.779 ]

See also in sourсe #XX -- [ Pg.216 , Pg.236 , Pg.240 , Pg.242 , Pg.243 , Pg.244 ]

See also in sourсe #XX -- [ Pg.344 , Pg.346 ]




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