Isotopes diamond

C isotope Diamond entries Graphite entries 1H- and 13C-nmr spectroscopy Low carbon silicomanganese ... 

Amato, I. "GE Achieves Dial-an Isotope Diamonds. Science, 653 iNovember I. 

Figure 3 Some horizontal mixing estimates as a function of space scale. Results are from a small-scale float deployment (triangles, Stommel, 1949), the tracer release experiment (squares, Ledwell et al., 1998), and some larger-scale advection-diffusion balances (circles, see later sections) and estimates from radium isotopes (diamonds,...

The isotope boron-10 is used as a control for nuclear reactors, as a shield for nuclear radiation, and in instruments used for detecting neutrons. Boron nitride has remarkable properties and can be used to make a material as hard as diamond. The nitride also behaves like an electrical insulator but conducts heat like a metal. 

Fig. 18-23 Observed correlation of isotopic composition of precipitation with ground temperature (gray diamonds Jouzel et ah, 1987), and predictions of simple isotopic models. A, prediction with constant a B, prediction with temperature-dependent a.

Figure All.l. A plot of the difference (residuals) between observed collagen 5 C values and values calculated from the DIFF for dp = +5, dn = +2, and f(F) = F , as a function of the dietary protein carbon content. Due to the eombination of eomposition and manipulated isotopic compositions of the different diets, some diets test the predictions of the DIFF more precisely than others. These are represented as squares (the remainder are represented as diamonds). Although the differenee has been minimized, it is not zero. Nevertheless, and especially for the more reliable reetangular points, the differenee is small, for a wide range of diets and collagen 8 values. Other combinations of dp, ds. and 1(F) give greater residuals.

Fig. 2.57. Pb isotopic compositions in volcanogenic Cu sulfide deposits in Japan. Diamond shape K], K2 and K3 indicate average values of Kuroko-type deposits Ki Taro (Cretaceous) K2 Northeast Japan (Miocene) K3 southwest Japan (Miocene). Note that the Shimokawa ores (solid square, Besshi subtype) and Yanahara ores (open square, Hitachi subtype), closely associated with sediments, tend to have slightly more radiogenic values than the others (solid circles) (Sato and Kase, 1996).

A. M. Friedman, H. Diamond and J. R. Huizenga Berkelium and Californium isotopes produced in neutron irradiation of Plutonium. Physic, Rev. 96, 1576 (1954). 

The semiconductors that have been the subject of numerous investigations in bulk, alloyed, or nanocrystalline form include Si, Ge, doped diamond, SiC, (B, Al, Ga, In)(N, P, As, Sb), and (Zn, Cd, Hg, Pb)(0, S, Se, Te). Nature has been exceptionally benign in providing NMR-active isotopes at natural abundances exceeding 4% for all of the preceding elements except in the cases of 13C, 33S, and 170, and enrichment with isotopic-labels has become more common. 

Fig. 4.6 Chromatographic separation factors for various uranium isotopes vs. 238U as a function of mass at 433 K. s = ln[(238U/1U)iv,aq/(238U/1U)vi,resin]- The field shift (FS) and vibrational (BM) contributions are of opposite sign. Triangles = calculated vibrational (Bigeleisen-Mayer) contribution, diamonds = calculated FS contribution, circles = measured effects, open squares = calculated effects. Note that agreement between calculation and experiment is quantitative. The correlation lines are drawn through even/even data points only (Data from Bigeleisen, J., J. Am. Chem. Soc., 118, 3676 (1996))...

Figure 1. Number of stable isotopes relative to atomic number (Z) for the elements. Mono-isotopic elements shown in gray diamonds. Elements discussed in this volume are shown as large gray circles. Other elements that have been the major focus of prior isotopic studies are shown in small white circles, and include H, C, O, and S. Nuclides that are radioactive but have very long half-lives are also shown in the diagram.

Figure 12. Extent of dissolution and re-precipitation between aqueous Fe(III) and hematite at 98°C calculated using Fe-enriched tracers. A. Percent Fe exchanged (F values) as calculated for the two enriched- Fe tracer experiments in parts B and C. Large diamonds reflect F values calculated from isotopic compositions of the solution. Small circles reflect F values calculated from isotopic compositions of hematite, which have larger errors due to the relatively small shifts in isotopic composition of the solid (see parts B and C). Curves show third-order rate laws that are fit to the data from the solutions. B. Tracer experiment using Fe-enriched hematite, and isotopically normal Fe(lll). C. Identical experiment as in part B, except that solution Fe(lll) is enriched in Te, and initial hematite had normal isotope compositions. Data from Skulan et al. (2002).

Figure 5. Relative abundances of the Kr, Xe isotopes (Huss and Lewis 1994) in presolar diamonds have been measured in bulk samples (= many grains) and are plotted relative to solar wind abundances. The terrestrial atmosphere is shown for comparison and displays a pattern close to mass dependent fractionation relative to the solar wind. The primary nucleosynthetic processes at the origin of the different nuclei are also listed. Both Kr and Xe are elevated in the r-process isotopes, whereas only Xe is also enriched in the p-isotopes. These patterns are a strong argument in favor of a supernova origin for the diamonds. Ne isotopes in presolar diamond is within the field of bulk meteorite data.

Clayton DD (1989) Origin of heavy xenon in meteoritic diamonds. Astrophys J 340 613-619 Clayton DD, Dwek E, Woosley SE (1977a) Isotopic anomalies and proton irradiation in the early solar system. Astrophys J 214 300-315... 

Nittler LR, Alexander CMOD (2003) Automated isotopic measurements of micron-sized dust application to meteoritic presolar silicon carbide. Geochim Cosmochim Acta 67 4961-4980 Nuth JA(1987) Small-particle physics and interstellar diamond. Nature 329 589... 

Ott U (1993) Physical and isotopic properties of surviving interstellar carbon phases. In Protostars Planets III. Levy Hand Lunine JI (eds) University of Arizona Press, Tucson, p 883-902 Ott U (1996) Interstellar diamond xenon and timescales of supernova ejecta. Astrophys J 463 344-348 Ott U, Begemann F, Yang J, Epstein S (1988) S-process krypton of variable isotopic composition in the Murchison meteorite. Nature 332 700-702... 

Virag A, Zinner E, Lewis RS, Tang M (1989) Isotopic compositions of H, C, and N in C8 diamonds from the Allende and Murray carbonaceous chondrites. Lunar Planet Sci XX 1158-1159 Volkening J, Papanastassiou DA (1989) Iron isotope anomalies. Astrophys J 347 L43-L46 Volkening J, Papanastassiou DA (1990) Zinc isotope anomalies. Astrophys J 358 L29-L32 Wadhwa M, Zinner EK, Crozaz G (1997) Manganese-chromium systematics in sulfides of unequilibrated enstatite chondrites. Meteorit Planet Sci 32 281-292... 

Figure 19. Plot of Li isotopic composition vs. inverse Li concentration for lakes and basinal/oilfield brines. Lakes open circle = major global lakes (Chan and Edmond 1988 Falkner et al. 1997) semi-open circle = western U.S. closed basin lakes (Tomascak et al. 2003). Oilfield brines inverted triangle = Williston basin, Saskatchewan (Bottomley et al. 2003) diamond = Israeli oilfields (Chan et al. 2002d). Mine waters (Canadian Shield basinal brines) square = Yellowknife, NWT (Bottomley et al. 1999) triangle = Sudbury, Ontario, area (Bottomley et al. 2003) star = Thompson, Manitoba, area (Bottomley et al. 2003). Average composition of seawater is included for reference.

Figure 15. Illustration of possible variations in isotopic fractionation between Fe(III),q and ferric oxide/ hydroxide precipitate (Aje(,n),q.Fenicppt) and precipitation rate. Skulan et al. (2002) noted that the kinetic AF (ni)aq-Feiricppt fractionation produced during precipitation of hematite from Fe(III), was linearly related to precipitation rate, which is shown in the dashed curve (precipitation rate plotted on log scale). The most rapid precipitation rate measured by Skulan et al. (2002) is shown in the black circle. The equilibrium Fe(III),-hematite fractionation is near zero at 98°C, and this is plotted (black square) to the left of the break in scale for precipitation rate. Also shown for comparison is the calculated Fe(III),q-ferrihydrite fractionation from the experiments of Bullen et al. (2001) (grey diamond), as discussed in the previous chapter (Chapter lOA Beard and Johnson 2004). The average oxidation-precipitation rates for the APIO experiments of Croal et al. (2004) are also noted, where the overall process is limited by the rate constant ki. As discussed in the text, if the proportion of Fe(III),q is small relative to total aqueous Fe, the rate constant for the precipitation of ferrihydrite from Fe(III), (Ai) will be higher, assuming first-order rate laws, although its value is unknown.

Bottinga Y. (1969b). Carbon isotope fractionation between graphite, diamond and carbon dioxide. Earth Planet. Sci. Letters, 5 301-307. 

Carbon and oxygen isotope analyses were carried out on marbles occurring in the epidote amphibolite masses from the Iratsu and Tonaru areas of the Sanbagawa metamorphic belt, central Shikoku, Japan and on diamond-bearing dolomitic marbles from the Kumdy-Kol site of the Kokchetav Massif, to compare them and to elucidate their origin. 

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