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Journal articles on the topic '18O'

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Published: 4 June 2021

Last updated: 27 April 2022

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1

Pan, Jian-Jung, Boris A. Kashemirov, Joanne Lee, Charles E. McKenna, Frank J. Devlin, and Philip J. Stephens. "Electronic circular dichroism of monomethyl [16O,17O,18O]-phosphate and [16O,17O,18O]-thiophosphate revisited." Bioorganic Chemistry 38, no. 1 (2010): 7–16. http://dx.doi.org/10.1016/j.bioorg.2009.02.001.

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2

Barbe, Alain, Marie-Renée De Backer-Barilly, Vladimir G. Tyuterev, and Serguei A. Tashkun. "Observations of infrared bands of asymmetrical ozone isotopologues ^16O^16O^18O and ^16O^18O^18O." Applied Optics 42, no. 25 (2003): 5136. http://dx.doi.org/10.1364/ao.42.005136.

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3

Herwartz, Daniel, Andreas Pack, Dmitri Krylov та ін. "Revealing the climate of snowball Earth from Δ17O systematics of hydrothermal rocks". Proceedings of the National Academy of Sciences 112, № 17 (2015): 5337–41. http://dx.doi.org/10.1073/pnas.1422887112.

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The oxygen isotopic composition of hydrothermally altered rocks partly originates from the interacting fluid. We use the triple oxygen isotope composition (17O/16O, 18O/16O) of Proterozoic rocks to reconstruct the 18O/16O ratio of ancient meteoric waters. Some of these waters have originated from snowball Earth glaciers and thus give insight into the climate and hydrology of these critical intervals in Earth history. For a Paleoproterozoic [∼2.3–2.4 gigayears ago (Ga)] snowball Earth, δ18O = −43 ± 3‰ is estimated for pristine meteoric waters that precipitated at low paleo-latitudes (≤35°N). To

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4

Luz, Boaz, and Eugeni Barkan. "Variations of 17O/16O and 18O/16O in meteoric waters." Geochimica et Cosmochimica Acta 74, no. 22 (2010): 6276–86. http://dx.doi.org/10.1016/j.gca.2010.08.016.

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5

Lowe, Gordon, and Barry V. L. Potter. "Synthesis of inorganic P1-[(S)-16O, 17O, 18O]pyrophosphate." Journal of Labelled Compounds and Radiopharmaceuticals 27, no. 1 (1989): 63–73. http://dx.doi.org/10.1002/jlcr.2580270110.

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6

Bechtel, C., and A. Zahn. "The isotope composition of water vapour: A powerful tool to study transport and chemistry of middle atmospheric water vapour." Atmospheric Chemistry and Physics Discussions 3, no. 4 (2003): 3991–4036. http://dx.doi.org/10.5194/acpd-3-3991-2003.

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Abstract. A one-dimensional chemistry model is applied to study the stable hydrogen (D) and stable oxygen isotope (17O, 18O) composition of water vapour in stratosphere and mesosphere. The stable isotope ratios of tropospheric H2O are determined by "physical'' fractionation effects, i.e. phase changes, diffusion processes, and mixing of air masses. Due to these processes water vapour entering the stratosphere (i) is mass-dependently fractionated (MDF), i.e. shifts in the isotope ratio 17O/16O are ~0.52 times of those of 18O/16O and (ii) shows isotope shifts in D/H, which are ~5 times of those

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7

Arnold, John R. P., Richard C. Bethell, and Gordon Lowe. "Chiral inorganic [16O, 17O, 18O]thiophosphate: Synthesis and stereochemical analysis." Bioorganic Chemistry 15, no. 3 (1987): 250–61. http://dx.doi.org/10.1016/0045-2068(87)90023-x.

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8

Zahn, A., P. Franz, C. Bechtel, J. U. Grooß, and T. Röckmann. "Modelling the budget of middle atmospheric water vapour isotopes." Atmospheric Chemistry and Physics 6, no. 8 (2006): 2073–90. http://dx.doi.org/10.5194/acp-6-2073-2006.

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Abstract. A one-dimensional chemistry model is applied to study the stable hydrogen (D) and stable oxygen isotope (17O, 18O) composition of water vapour in stratosphere and mesosphere. In the troposphere, this isotope composition is determined by "physical'' fractionation effects, that are phase changes (e.g. during cloud formation), diffusion processes (e.g. during evaporation from the ocean), and mixing of air masses. Due to these processes water vapour entering the stratosphere first shows isotope depletions in D/H relative to ocean water, which are ~5 times of those in 18O/16O, and secondl

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9

Malová Križková, Petra, Susanne Prechelmacher, Alexander Roller, and Friedrich Hammerschmidt. "Chemical Synthesis of (RP)- and (SP)-[16O,17O,18O]Phosphoenol Pyruvate." Journal of Organic Chemistry 82, no. 19 (2017): 10310–18. http://dx.doi.org/10.1021/acs.joc.7b01783.

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10

Arnold, John R. P., and Gordon Lowe. "Synthesis and stereochemical analysis of chiral inorganic [16O, 17O, 18O]thiophosphate." Journal of the Chemical Society, Chemical Communications, no. 11 (1986): 865. http://dx.doi.org/10.1039/c39860000865.

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11

LOWE, GORDON, and MARTIN J. PARRATT. "Synthesis and Stereochemical Analysis of Chiral [16O,17O,18O]Sulfate Esters." Annals of the New York Academy of Sciences 471, no. 1 International (1986): 310–13. http://dx.doi.org/10.1111/j.1749-6632.1986.tb48051.x.

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12

Itano, H. A., and T. Hirota. "A two-molecule mechanism of haem degradation." Biochemical Journal 226, no. 3 (1985): 767–71. http://dx.doi.org/10.1042/bj2260767.

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Coupled oxidation of octaethylhaemin and phenylhydrazine hydrochloride with 16,16O2 and 18,18O2 produced octaethyl[16O]verdohaemochrome and octaethyl[18O]-verdohaemochrome respectively. Reactions of these products with 16,16O2 in the presence of phenylhydrazine hydrochloride yielded octaethyl[16O, 16O]biliverdin and octaethyl[18O, 16O]biliverdin. The same reactions with 18,18O2 yielded octaethyl[16O, 18O]biliverdin and octaethyl[18O, 18O]biliverdin. Accordingly, the two oxygen atoms of biliverdin are incorporated from different O2 molecules in separate reactions, namely the formation of verdoh

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13

Krylov, D. P., and A. B. Kuznetsov. "Oxygen isotopic fractionation in TiO2 polymorphs (rutile, anatase, brookite) estimated from “first principles”." Доклады Академии наук 489, no. 1 (2019): 62–64. http://dx.doi.org/10.31857/s0869-5652489162-64.

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Temperature relations of b-factors for 18O/16O substitutions in TiO2 polymorphs have been determined using the density functional theory (DFT): 1000lnbrt(18O/16O) = 6,93039x - 0,08158x2 + 0,00116x3 + 0,08305*P, 1000lnbant(18O/16O) = 7,34275x - 0,09906x2 + 0,00153x3 + 0,08027*P, 1000lnbbrk(18O/16O) = 7,19088x - 009157x2 + 0,00139x3 + 0,07601*P, x = 106/T(K)2, P - pressure (GPa). The relations can be applied for isotope thermometry if combined with -factors of coexisting phases.

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14

Rudchik, Adam T., Stanislaw Kliczewski, Kostyantyn A. Chercas, et al. "Elastic and inelastic scattering of 6Li + 18O versus 7Li + 18O and 6Li + 16O." Nuclear Physics A 922 (February 2014): 71–83. http://dx.doi.org/10.1016/j.nuclphysa.2013.10.013.

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15

Rudchik, A. T., Yu O. Shyrma, K. W. Kemper, et al. "Elastic and inelastic scattering of 13C + 18O versus 12C + 18O and 13C + 16O." Nuclear Physics A 852, no. 1 (2011): 1–14. http://dx.doi.org/10.1016/j.nuclphysa.2011.01.004.

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16

Bleasdale, Christine, Martin K. Ellis, Peter B. Farmer, et al. "Synthesis and spectroscopic characterisation of 3-chloroperbenzoic acid-17O,18O, nitrosobenzene-17O,18O and nitrosobenzene-15N." Journal of Labelled Compounds and Radiopharmaceuticals 33, no. 8 (1993): 739–46. http://dx.doi.org/10.1002/jlcr.2580330810.

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17

Luz, B., and E. Barkan. "Net and gross oxygen production from O2/Ar, 17O/16O and 18O/16O ratios." Aquatic Microbial Ecology 56 (September 3, 2009): 133–45. http://dx.doi.org/10.3354/ame01296.

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18

Fedorova, O. M., Anatoly Yakovlevich Fishman, Tatiana Eugenievna Kurennykh, Vladimir Borisovich Vykhodets та V. B. Vykhodets. "Isotope Exchange between ¹⁸O₂ Gas and Mechanoactivated Oxide NdMnO_3+δ". Defect and Diffusion Forum 333 (січень 2013): 193–98. http://dx.doi.org/10.4028/www.scientific.net/ddf.333.193.

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sotope exchange of oxygen 18О2 with oxides NdMnO3+δ was investigated. The oxide was obtained from oxides Nd2O3 and Mn2O3 using a ceramic technology with annealing in air at 1400°C for 90 hours followed by cooling in a furnace. A planetary mill AGO-2 with a centrifugal factor of g = 60 was used for mechanical treatment of oxides. The study of isotope exchange was carried out by nuclear microanalysis. The concentration of the isotopes 18O and 16O in oxides was determined using a Van de Graaff accelerator and 18O(p, α)15N and 16O(d, p)17O* reactions at the energies of incident beams 762 and 900 k

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19

Rudchik, A. T., K. A. Chercas, K. W. Kemper, et al. "6Li(18O, 17O)7Li reaction and comparison of 6, 7Li+16, 17, 18O potentials." Nuclear Physics A 927 (July 2014): 209–19. http://dx.doi.org/10.1016/j.nuclphysa.2014.04.018.

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20

Kawashima, Koichiro, Ren Iwata, Kyuya Kogure, Hitoshi Ohtomo, Hikonojo Orihara, and Tatsuo Ido. "Activation Autoradiography: Imaging and Quantitative Determination of Endogenous and Exogenous Oxygen in the Rat Brain." Journal of Cerebral Blood Flow & Metabolism 7, no. 3 (1987): 272–79. http://dx.doi.org/10.1038/jcbfm.1987.63.

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Endogenous and exogenous oxygen in the rat brain were quantitatively determined using an autoradiographic technique. The oxygen images of frozen and dried rat brain sections were obtained as 18F images by using the 16O (3He,p)18F reaction for endogenous 16O images and the 18O(p,n)18F reaction for endogenous and exogenous 18O images. These autoradiograms demonstrated the different distribution of oxygen between gray and white matter. These images also allowed differentiation of the individual structures of hippocampal formation, owing to the differing water content of the various structures. Lo

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21

Savarino, Joel, and Mark H. Thiemens. "Mass-Independent Oxygen Isotope (16O,17O,18O) Fractionation Found in Hx, OxReactions." Journal of Physical Chemistry A 103, no. 46 (1999): 9221–29. http://dx.doi.org/10.1021/jp991221y.

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22

Bondì, M., F. Cappuzzello, C. Agodi, et al. "Selectivity of the12C(18O,16O)14C reaction." Известия Российской академии наук. Серия физическая 78, no. 7 (2014): 820–21. http://dx.doi.org/10.7868/s0367676514070059.

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23

Potter, Barry V. L. "Synthesis of [17O]- and [18O]-labelled hypophosphate." Journal of Labelled Compounds and Radiopharmaceuticals 27, no. 8 (1989): 955–63. http://dx.doi.org/10.1002/jlcr.2580270812.

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24

Gray, John, and Alan Guest. "17O and 18O analysis of heavy water." International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes 37, no. 9 (1986): 969–71. http://dx.doi.org/10.1016/0883-2889(86)90248-0.

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25

Brand, Willi A., Sergey S. Assonov та Tyler B. Coplen. "Correction for the 17O interference in δ(13C) measurements when analyzing CO2 with stable isotope mass spectrometry (IUPAC Technical Report)". Pure and Applied Chemistry 82, № 8 (2010): 1719–33. http://dx.doi.org/10.1351/pac-rep-09-01-05.

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Measurements of δ(13C) determined on CO2 with an isotope-ratio mass spectrometer (IRMS) must be corrected for the amount of 17O in the CO2. For data consistency, this must be done using identical methods by different laboratories. This report aims at unifying data treatment for CO2 IRMS by proposing (i) a unified set of numerical values, and (ii) a unified correction algorithm, based on a simple, linear approximation formula. Because the oxygen of natural CO2 is derived mostly from the global water pool, it is recommended that a value of 0.528 be employed for the factor λ, which relates differ

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26

Rollinson, Veronica R., Julie Granger, Sydney C. Clark, et al. "Seasonality of nitrogen sources, cycling, and loading in a New England river discerned from nitrate isotope ratios." Biogeosciences 18, no. 11 (2021): 3421–44. http://dx.doi.org/10.5194/bg-18-3421-2021.

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Abstract. Coastal waters globally are increasingly impacted due to the anthropogenic loading of nitrogen (N) from the watershed. To assess dominant sources contributing to the eutrophication of the Little Narragansett Bay estuary in New England, we carried out an annual study of N loading from the Pawcatuck River. We conducted weekly monitoring of nutrients and nitrate (NO3-) isotope ratios (15N / 14N, 18O / 16O, and 17O / 16O) at the mouth of the river and from the larger of two wastewater treatment facilities (WWTFs) along the estuary, as well as seasonal along-river surveys. Our observation

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27

Palmerini, Sara, Sergio Cristallo, Luciano Piersanti, Diego Vescovi, and Maurizio Busso. "Group II Oxide Grains: How Massive Are Their AGB Star Progenitors?" Universe 7, no. 6 (2021): 175. http://dx.doi.org/10.3390/universe7060175.

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Presolar grains and their isotopic compositions provide valuable constraints to AGB star nucleosynthesis. However, there is a sample of O- and Al-rich dust, known as group 2 oxide grains, whose origin is difficult to address. On the one hand, the 17O/16O isotopic ratios shown by those grains are similar to the ones observed in low-mass red giant stars. On the other hand, their large 18O depletion and 26Al enrichment are challenging to account for. Two different classes of AGB stars have been proposed as progenitors of this kind of stellar dust: intermediate mass AGBs with hot bottom burning, o

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28

Cliff, Steven S., and Mark H. Thiemens. "High-Precision Isotopic Determination of the 18O/16O and 17O/16O Ratios in Nitrous Oxide." Analytical Chemistry 66, no. 17 (1994): 2791–93. http://dx.doi.org/10.1021/ac00089a031.

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29

Naka, Sadahiro, Toshimitsu Watanabe, Yasukazu Kanai, et al. "Improved Stability and Practicality for Synthesis of 4-Borono-2-[18F]fluoro-l-phenylalanine by Combination of [18O]O2 Single-Use and [18F]CH3COOF Labeling Agents." Nuclear Medicine and Molecular Imaging 56, no. 2 (2022): 86–95. http://dx.doi.org/10.1007/s13139-021-00719-1.

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Abstract Purpose 4-Borono-2-[18F]fluoro-l-phenylalanine ([18F]FBPA) synthesized with [18F]F2, produced using the 18O(p, n)18F reaction, has been reported for increasing radioactivity. However, a dedicated system and complex procedure is required to reuse the costly [18O]O2 gas; also, the use of [18F]F2 as a labeling agent reduces the labeling rate and radiochemical purity. We developed a stable and practical method for [18F]FBPA synthesis by combining [18F]F2, produced using a [18O]O2 single-use system, and a [18F]CH3COOF labeling agent. Methods The produced [18F]F2 was optimized, and then [18

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30

Wang, Luohuan, Jun Su, Yangping Shen та ін. "Measurement of the ¹⁸O(α, γ)²²Ne resonances at JUNA". EPJ Web of Conferences 260 (2022): 11015. http://dx.doi.org/10.1051/epjconf/202226011015.

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22Ne(α,n)25Mg is one of the main neutron sources of the s process. 22Ne is produced by the 14N(α, γ)18F(β+)18O(α, γ)22Ne reaction chain in the helium burning, thus, the production rate of 22Ne is dominated by 14N(α,γ)18F and 18O(α,γ)22Ne. At the astrophysical relevant temperatures, the 18O(α,γ)22Ne reaction rates are determined by several low-energy resonances. In this work, the 18O(α,γ)22Ne reaction was measured at the 400 kV accelerator of Jinping Underground Nuclear Astrophysics experiment (JUNA). The γ-ray yields of the resonances between 470 to 770 keV were obtained.

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31

Gorbenko, O. Yu, A. R. Kaul, N. A. Babushkina, L. M. Belova, and B. Guettler. "Colossal Isotope Shift of the Metal-Insulator Transition Temperature in Epitaxial Thin Films of (La1-y Pry)0·7Ca0·3MnO3." Australian Journal of Physics 52, no. 2 (1999): 269. http://dx.doi.org/10.1071/p98066.

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A colossal shift of the maximum resistivity temperature induced by oxygen isotope exchange was registered for 60 nm thick films of the solid solution La0·35Pr0·35Ca0·3MnO3 on perovskite substrates. The magnitude of the effect depends on lattice strain resulting in the largest shift for the film on LaAlO3: the 16O sample showed a metal-insulator transition at 182 K, whereas the 18O sample was insulating down to 4·2 K, which is the highest difference ever reported for CMR manganites. An XRD and Raman spectrometry study indicates no difference in chemical composition or structure for the 18O and

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32

Young, Edward D., Marilyn L. Fogel, Douglas Rumble, and Thomas C. Hoering. "Isotope-ratio-monitoring of O2 for microanalysis of 18O/16O and 17O/16O in geological materials." Geochimica et Cosmochimica Acta 62, no. 18 (1998): 3087–94. http://dx.doi.org/10.1016/s0016-7037(98)00215-4.

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33

Luz, Boaz, and Eugeni Barkan. "The isotopic ratios 17O/16O and 18O/16O in molecular oxygen and their significance in biogeochemistry." Geochimica et Cosmochimica Acta 69, no. 5 (2005): 1099–110. http://dx.doi.org/10.1016/j.gca.2004.09.001.

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34

Bondì, M., F. Cappuzzello, C. Agodi, et al. "Selectivity of the 12C(18O, 16O)14C reaction." Bulletin of the Russian Academy of Sciences: Physics 78, no. 7 (2014): 605–6. http://dx.doi.org/10.3103/s1062873814070053.

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35

Werner, Roland. "The Online 18O/ 16O Analysis: Development and application." Isotopes in Environmental and Health Studies 39, no. 2 (2003): 85–104. http://dx.doi.org/10.1080/1025601031000108642.

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36

Han, Sung Y., Ellen M. Shulman-Roskes, Konrad Misiura, et al. "Synthesis of 17O (and 18O) labelled isophosphoramide mustard." Journal of Labelled Compounds and Radiopharmaceuticals 34, no. 3 (1994): 247–54. http://dx.doi.org/10.1002/jlcr.2580340307.

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37

Rich, Tyvin, Dongfeng Pan, Mahendra Chordia, et al. "18Oxygen Substituted Nucleosides Combined with Proton Beam Therapy: Therapeutic Transmutation In Vitro." International Journal of Particle Therapy 7, no. 4 (2021): 11–18. http://dx.doi.org/10.14338/ijpt-d-20-00036.1.

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Abstract Purpose Proton therapy precisely delivers radiation to cancers to cause damaging strand breaks to cellular DNA, kill malignant cells, and stop tumor growth. Therapeutic protons also generate short-lived activated nuclei of carbon, oxygen, and nitrogen atoms in patients as a result of atomic transmutations that are imaged by positron emission tomography (PET). We hypothesized that the transition of 18O to 18F in an 18O-substituted nucleoside irradiated with therapeutic protons may result in the potential for combined diagnosis and treatment for cancer with proton therapy. Materials and

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38

Heikkilä, Arto, Lars E. B. Johansson, and Hans Olofsson. "On the Star-formation History in the LMC: Observations of the Interstellar C18O/C17O Ratio." Symposium - International Astronomical Union 190 (1999): 275–76. http://dx.doi.org/10.1017/s0074180900118029.

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The re-cycling of gas between stars and the interstellar medium (ISM) leads to a gradual metal-enrichment of a galaxy. Accordingly, information on the chemical evolution of a galaxy, e.g., its star-formation history (SFH), is contained in the chemical composition of the ISM. In this context, the abundance ratio of the rare oxygen isotopes, 18O/17O (usually taken as the C18O/C17O column density ratio), appears to be a particularly promising probe of the SFH. According to present understanding of stellar nucleosynthesis, 17O is mainly produced in intermediate-mass stars (say a few to ten M⊙) whi

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39

Hamblin, M. R., J. H. Cummins, and B. V. L. Potter. "Mung bean (Phaseolus aureus) nuclease. A mechanistic investigation of the DNA-cleavage reaction using a dinucleoside phosphorothioate." Biochemical Journal 241, no. 3 (1987): 827–33. http://dx.doi.org/10.1042/bj2410827.

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Mung-bean (Phaseolus aureus) nuclease has been found to cleave the Sp diastereoisomer of 5′-O-thymidyl 3′-O-(2′-deoxyadenosyl)phosphorothioate, (Sp)-d[Ap(S)T], in 18O-labelled water with inversion of configuration at phosphorus to give (Sp)-thymidine 5′-[16O, 18O]phosphorothioate, the stereochemistry of which was deduced by methylation to (Rp, Sp)-thymidine 5′-S-methyl-O-methyl-[16O,18O]phosphorothioate and 31P-n.m.r. analysis. This result is consistent with a mechanism involving a direct ‘in-line’ attack of water on DNA for the nuclease-catalysed reaction without the involvement of a covalent

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40

Ham, William K., Steven W. Keller, James N. Michaels, et al. "Partial substitution of 18O in YBa2Cu3O7: Investigations of inhomogeneities and their effect on Tc." Journal of Materials Research 4, no. 3 (1989): 504–14. http://dx.doi.org/10.1557/jmr.1989.0504.

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The possibility of site-selective substitution of 18O into YBa2Cu3O7 was explored. Samples containing various quantities of 18O were prepared by processing in 18O2 both at 950 °C and at 400 °C. The samples were characterized by secondary ion mass spectroscopy (SIMS), temperature programmed desorption (TPD) and reduction (TPR), Raman spectroscopy, and magnetization measurements. Measurements of the shifts in the Raman active modes with 18O substitution and of the ratios of 18O to 16O by TPD, TPR, and SIMS show that even for temperatures as low as 400 °C and times as short as 2 h. 18O is not sub

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41

van Wijk, R., C. H. M. Marée, O. L. J. Gijzeman, F. H. P. M. Habraken, and J. W. Geus. "18O-exchange with the substrate during 18O oxidation of Cu particles supported on 16O-oxidised Si(100)." Applied Surface Science 99, no. 3 (1996): 197–204. http://dx.doi.org/10.1016/0169-4332(96)00104-3.

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42

Köhler, Th, P. Blüm, G. Büche, et al. "Precision measurement of strong interaction isotope effects in antiprotonic 16O, 17O, and 18O atoms." Physics Letters B 176, no. 3-4 (1986): 327–33. http://dx.doi.org/10.1016/0370-2693(86)90173-5.

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43

Okruszek, Andrzej, Piotr Guga, and Wojciech J. Stec. "Novel approach to the synthesis of isotopomeric monoalkyl [16O,17O,18O]phosphates. The stereospecific one-pot conversion of (RP)-thymidine 3′-(4-nitrophenyl)phosphorothioate into (RP)-thymidine 3′-[16O,17O,18O]phosphate." J. Chem. Soc., Chem. Commun., no. 8 (1987): 594–95. http://dx.doi.org/10.1039/c39870000594.

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44

Klemm, A., A. Banerjee, and S. Hoernes. "A New Intracrystalline Isotope Effect: 18O under the Faces of Amethyst." Zeitschrift für Naturforschung A 45, no. 11-12 (1990): 1374–76. http://dx.doi.org/10.1515/zna-1990-11-1225.

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AbstractThe concentration of 18O within well formed crystals of amethyst was found to vary beneath the different growth faces, increasing in the order z→ r→m. The 18O/16O fractionation factor between the faces m and z was measured as 1.0007.

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45

Chai, C. L. L., W. A. Loughlin, and G. Lowe. "The stereochemical course of sulphuryl transfer catalysed by arylsulphatase II from Aspergillus oryzae." Biochemical Journal 287, no. 3 (1992): 805–12. http://dx.doi.org/10.1042/bj2870805.

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Phenyl [(R)-16O,17O,18O]sulphate was synthesized and used to study the stereochemical course of sulphuryl transfer to p-cresol catalysed by arylsulphatase II from Aspergillus oryzae. The reaction was shown to proceed with retention of configuration at the sulphur atom, providing evidence for the involvement of a sulpho-enzyme intermediate on the reaction pathway.

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Webster, C. R. "Water Isotope Ratios D/H, 18O/16O, 17O/16O in and out of Clouds Map Dehydration Pathways." Science 302, no. 5651 (2003): 1742–45. http://dx.doi.org/10.1126/science.1089496.

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Braaz, Reinhard, Wolfgang Armbruster, and Dieter Jendrossek. "Heme-Dependent Rubber Oxygenase RoxA of Xanthomonas sp. Cleaves the Carbon Backbone of Poly(cis-1,4-Isoprene) by a Dioxygenase Mechanism." Applied and Environmental Microbiology 71, no. 5 (2005): 2473–78. http://dx.doi.org/10.1128/aem.71.5.2473-2478.2005.

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ABSTRACT Oxidative cleavage of poly(cis-1,4-isoprene) by rubber oxygenase RoxA purified from Xanthomonas sp. was investigated in the presence of different combinations of 16O2, 18O2, H2 16O, and H2 18O. 12-Oxo-4,8-dimethyl-trideca-4,8-diene-1-al (ODTD; m/z 236) was the main cleavage product in the absence of 18O-compounds. Incorporation of one 18O atom in ODTD was found if the cleavage reaction was performed in the presence of 18O2 and H2 16O. Incubation of poly(cis-1,4-isoprene) (with RoxA) or of isolated unlabeled ODTD (without RoxA) with H2 18O in the presence of 16O2 indicated that the car

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Ito, Shigeki, Takuya Saze, Hitoshi Sakane, Satoshi Ito, Shinichi Ito, and Kunihide Nishizawa. "Tritium in [18O]water containing [18F]fluoride for [18F]FDG synthesis." Applied Radiation and Isotopes 61, no. 6 (2004): 1179–83. http://dx.doi.org/10.1016/j.apradiso.2004.04.002.

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Koehler, P. E., H. D. Knox, D. A. Resler, R. O. Lane та G. F. Auchampaugh. "Structure of 19O from measurement and R-matrix analysis of σ(θ) for 18O(n, n)18O and 18O(n, n′)18O∗(1.98 MeV)". Nuclear Physics A 453, № 3 (1986): 429–62. http://dx.doi.org/10.1016/0375-9474(86)90446-x.

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Saitoh, Hiroaki, Akira Manabe, and Tsunenobu Kimoto. "Epitaxial Growth of 4H-SiC {0001} with Large Off-Angles by Chemical Vapor Deposition." Materials Science Forum 527-529 (October 2006): 223–26. http://dx.doi.org/10.4028/www.scientific.net/msf.527-529.223.

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We have investigated the morphology and doping characteristics of 4H-SiC epilayers grown on 13o-22o off-axis (0001) substrates by horizontal hot-wall CVD. Step bunching is not observed on 18o off-axis substrates as well as on other substrates with large off-angles. The rms roughness is a minimum (as small as 0.10 nm) on 18o off-axis (0001). Under C-rich condition (C/Si >1.0), the donor concentration increases by increasing the off-angle, when the off-angle is larger than 15o. This trend in doping characteristic is enhanced in CVD growth at 1450-1500oC. At a high temperature of 1600oC, howev

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