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Journal articles on the topic 'Cobalt isotope'

Author: Grafiati

Published: 4 June 2021

Last updated: 2 February 2022

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1

Takami, Yuta, Satoshi Yanase, and Takao Oi. "Observation of Lithium Isotope Effects Accompanying Electrochemical Release from Lithium Cobalt Oxide." Zeitschrift für Naturforschung A 68, no. 1-2 (February 1, 2013): 73–78. http://dx.doi.org/10.5560/zna.2012-0080.

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Change in the lithium isotope composition in a lithium cobalt oxide (LiCoO2) cathode for lithium ion secondary batteries accompanying the electrochemical lithium release from the cathode into an organic electrolyte solution was observed. The 7Li/6Li isotopic ratios of the electrodes after the release of 37.2 to 55:4% lithium were 1.018 to 1.033 times smaller than that before the release. This means that the heavier isotope, 7Li, is preferentially transferred to the electrolyte solution.

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2

Barrett, Kendall E., Hailey A. Houson, Wilson Lin, Suzanne E. Lapi, and Jonathan W. Engle. "Production, Purification, and Applications of a Potential Theranostic Pair: Cobalt-55 and Cobalt-58m." Diagnostics 11, no. 7 (July 9, 2021): 1235. http://dx.doi.org/10.3390/diagnostics11071235.

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The emerging success of [68Ga/177Lu]Ga/Lu-DOTATATE as a theranostic pair has spurred interest in other isotopes as potential theranostic combinations. Here, we review cobalt-55 and cobalt-58m as a potential theranostic pair. Radionuclidically pure cobalt-55 and cobalt-58m have been produced on small cyclotrons with high molar activity. In vitro, DOTATOC labeled with cobalt has shown greater affinity for SSTR2 than DOTATOC labeled with gallium and yttrium. Similarly, [58mCo]Co-DOTATATE has shown improved cell-killing capabilities as compared to DOTATATE labeled with either indium-111 or lutetium-177. Finally, PET imaging with an isotope such as cobalt-55 allows for image acquisition at much later timepoints than gallium, allowing for an increased degree of biological clearance of non-bound radiotracer. We discuss the accelerator targetry and radiochemistry used to produce cobalt-55,58m, emphasizing the implications of these techniques to downstream radiotracers being developed for imaging and therapy.

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3

Goodz, M. D., D. H. Watkinson, V. Smejkal, and Z. Pertold. "Sulphur-isotope geochemistry of silver–selpnarsenide vein mineralization, Cobalt, Ontario." Canadian Journal of Earth Sciences 23, no. 10 (October 1, 1986): 1551–67. http://dx.doi.org/10.1139/e86-146.

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The silver–sulpharsenide vein deposits of Cobalt, Ontario, crosscut basement Archean metavolcanic rocks, Proterozoic strata, and younger Proterozoic diabase sills. A petrographic and sulphur-isotope study of the metallic minerals was initiated to assess possible genetic models of vein formation. Discrete differences exist between the sulphur-isotope compositions of basement sulphides (δ34S = + 4.0‰), brecciated wall-rock sulphides (+ 3.5‰), and vein sulphides (+ 2.3‰). The δ34S values consistently increase with distance from the vein centres. Sulphur-isotope fractionation trends are similar for all the vein deposits studied. Sulphur-isotope data suggest that sulphides were deposited between 130 and 254 °C. Based on the assumption of equilibrium between chalcopyrite and galena, the initial δ34S of the fluid was between + 5.0 and + 11.0‰. The release of sulphur during the reaction of Archean pyrite with Proterozoic formational brines to form pyrrhotite is proposed to explain the heavy sulphur isotopic composition of the fluid. This process could also have provided the Ni, Co, and As, known to be concentrated in some pyrite, that was deposited in the silver veins. Interpretation of mineral paragenesis and geothermometry indicate that temperature decreased and aS2 increased as deposition proceeded.

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4

Takami, Yuta, Satoshi Yanase, and Takao Oi. "Lithium Isotope Effects upon Electrochemical Release from Lithium Cobalt Oxide to Non-Lithium Electrolyte Solution." Zeitschrift für Naturforschung A 69, no. 1-2 (February 1, 2014): 97–103. http://dx.doi.org/10.5560/zna.2013-0080.

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Lithium was electrochemically released from a lithium cobalt oxide (LiCoO2) cathode to an ethylene carbonate-based organic electrolyte solution containing no lithium ions, and the change in the lithium isotope composition of the cathode was measured. The 7Li/6Li isotopic ratio of the electrode was practically unchanged before and after the 45% - 62% lithium release, which meant that the lithium release accompanied no isotope preference. This result is quite contrastive to the previous one; when lithium was released to an organic electrolyte solution containing lithium ions, the 7Li/6Li ratio of the cathode became 1.018 to 1.033 times smaller than that before the release. It was induced that the kind of electrolyte solution controlled the attainment of the lithium isotope exchange equilibrium between the cathode and the electrolyte solution.

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5

Banerjee, Ruma, Agnieszka Dybala-Defratyka, and Piotr Paneth. "Quantum catalysis in B 12 -dependent methylmalonyl-CoA mutase: experimental and computational insights." Philosophical Transactions of the Royal Society B: Biological Sciences 361, no. 1472 (July 12, 2006): 1333–39. http://dx.doi.org/10.1098/rstb.2006.1866.

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B 12 -dependent methylmalonyl-CoA mutase catalyses the interchange of a hydrogen atom and the carbonyl-CoA group on adjacent carbons of methylmalonyl-CoA to give the rearranged product, succinyl-CoA. The first step in this reaction involves the transient generation of cofactor radicals by homolytic rupture of the cobalt–carbon bond to generate the deoxyadenosyl radical and cob(II)alamin. This step exhibits a curious sensitivity to isotopic substitution in the substrate, methylmalonyl-CoA, which has been interpreted as evidence for kinetic coupling. The magnitude of the isotopic discrimination is large and a deuterium isotope effect ranging from 35.6 at 20 °C to 49.9 at 5 °C has been recorded. Arrhenius analysis of the temperature dependence of this isotope effect provides evidence for quantum tunnelling in this hydrogen transfer step. The mechanistic complexity of the observed rate constant for cobalt–carbon bond homolysis together with the spectroscopically silent nature of many of the component steps limits the insights that can be derived by experimental approaches alone. Computational studies using a newly developed geometry optimization scheme that allows determination of the transition state in the full quantum mechanical/molecular mechanical coordinate space have yielded novel insights into the strategy deployed for labilizing the cobalt–carbon bond and poising the resulting deoxyadenosyl radical for subsequent hydrogen atom abstraction.

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6

Lee, Chan Gyu, Yoshiaki Iijima, and Ken-Ichi Hirano. "Isotope Effect for Diffusion of Cobalt in an Iron-12 at.% Cobalt Alloy." Defect and Diffusion Forum 66-69 (January 1991): 433–38. http://dx.doi.org/10.4028/www.scientific.net/ddf.66-69.433.

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7

Thorpe, R. I., M. D. Goodz, I. R. Jonasson, and J. Blenkinsop. "Lead-isotope study of mineralization in the Cobalt district, Ontario." Canadian Journal of Earth Sciences 23, no. 10 (October 1, 1986): 1568–75. http://dx.doi.org/10.1139/e86-147.

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Twenty-seven lead-isotope analyses for galena specimens from 14 localities in the Cobalt district represent sulphide-rich interflow sedimentary units in the Archean volcanic sequence, mineralized zones, fracture fillings, and local sulphide concentrations in the Cobalt Group (Proterozoic) sedimentary rocks, and vein-filling and breccia-cementing sulphides from within and near silver–arsenide veins. The analyses define a very homogeneous composition, averaging 206Pb/204Pb = 14.732, 2O7Pb/204Pb = 15.114, and 208Pb/204Pb = 34.301, for lead from these different geological settings. This result is in agreement with textural observations indicating a late paragenetic position for galena in the different settings mentioned. The model age for this lead is in general accord with the U–Pb age obtained in a study by Andrews et al. for a Nipissing diabase sheet at Gowganda.About one third of the galena specimens are interpreted by a two-stage evolution model to have formed or been remobilized during an event in the time range 1650–1945 Ma. The timing and character of this event are not clearly defined. The radiogenic composition of a specimen from the Pan Silver property is comparable to radiogenic values reported by Thorpe and suggests a young galena-forming event in the area.The lead-isotope data are permissive evidence for a genetic link between the Nipissing diabase sheets and mineralization of a variety of types in the Cobalt district. The metal source is not clearly indicated, but one analysis for Archean interflow sulphides suggests than an Archean source is unlikely for the lead in the silver–arsenide veins and other mineralized zones.

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8

Ratzke, K., A. Heesemann, and F. Faupel. "The vanishing isotope effect of cobalt diffusion in Fe39Ni40B21glass." Journal of Physics: Condensed Matter 7, no. 39 (September 25, 1995): 7663–68. http://dx.doi.org/10.1088/0953-8984/7/39/008.

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9

Lee, Chan Gyu, Yoshiaki Iijima, and K. Hirano. "Self-Diffusion and Isotope Effect in Face-Centred Cubic Cobalt." Defect and Diffusion Forum 95-98 (January 1993): 723–28. http://dx.doi.org/10.4028/www.scientific.net/ddf.95-98.723.

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10

Iijima, Yoshiaki, Kazuhiro Kimura, Chan-Gyu Lee, and Ken-ichi Hirano. "Impurity Diffusion and Isotope Effect of Cobalt in α-Iron." Materials Transactions, JIM 34, no. 1 (1993): 20–26. http://dx.doi.org/10.2320/matertrans1989.34.20.

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11

Hashiguchi, Minako, Isao Sakaguchi, Reona Miyazaki, Kazunori Takada, and Naoki Ohashi. "Cobalt Doping as the Controlling Factor of Oxygen Diffusivity in ZnO by More than Four Orders of Magnitude." Defect and Diffusion Forum 363 (May 2015): 85–90. http://dx.doi.org/10.4028/www.scientific.net/ddf.363.85.

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Oxygen diffusivity in ZnO ceramics doped with cobalt was investigated using an isotope tracer method. The oxygen isotope (18O) was introduced by 18O/16O exchange annealing in an 18O2 atmosphere, and the depth profile of the 18O concentration was analyzed by secondary ion mass spectrometry. The results show that oxygen diffusivity in ZnO steeply increases with increasing Co concentration. In fact, the bulk oxygen diffusivity in 15 mol% Co-doped ZnO was four orders of magnitude greater than that of nominally non-doped ZnO. Oxygen diffusivity at grain boundaries was also enhanced by Co-doping.

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12

Qi, Yanying, Jia Yang, Anders Holmen, and De Chen. "Investigation of C1 + C1 Coupling Reactions in Cobalt-Catalyzed Fischer-Tropsch Synthesis by a Combined DFT and Kinetic Isotope Study." Catalysts 9, no. 6 (June 19, 2019): 551. http://dx.doi.org/10.3390/catal9060551.

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Understanding the chain growth mechanism is of vital importance for the development of catalysts with enhanced selectivity towards long-chain products in cobalt-catalyzed Fischer-Tropsch synthesis. Herein, we discriminate various C1 + C1 coupling reactions by theoretical calculations and kinetic isotope experiments. CHx(x=0−3), CO, HCO, COH, and HCOH are considered as the chain growth monomer respectively, and 24 possible coupling reactions are first investigated by theoretical calculations. Eight possible C1 + C1 coupling reactions are suggested to be energetically favorable because of the relative low reaction barriers. Moreover, five pathways are excluded where the C1 monomers show low thermodynamic stability. Effective chain propagation rates are calculated by deconvoluting from reaction rates of products, and an inverse kinetic isotope effect of the C1 + C1 coupling reaction is observed. The theoretical kinetic isotope effect of CO + CH2 is inverse, which is consistent with the experimental observation. Thus, the CO + CH2 pathway, owing to the relatively lower barrier, the high thermodynamic stability, and the inverse kinetic isotope effect, is suggested to be a favorable pathway.

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13

Kamenev, Dmitry Yurievich, Ivan Petrovich Moshurov, Bronislava Borisovna Kravets, and Nataliya Viktorovna Korotkikh. "Brachytherapy is a Promising Treatment for Prostate Cancer." Vestnik of Experimental and Clinical Surgery 10, no. 1 (August 8, 2017): 79–85. http://dx.doi.org/10.18499/2070-478x-2017-10-1-79-85.

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Abstract – prostate Cancer is one of the most common cancers among men. Incidence is second only to tumors of the broncho- pulmonary system. In recent years significantly increased the interest in contact radiation methods of treatment of this disease (brachytherapy). In the treatment of prostate cancer there is experience of application of different source of dose-rate used sources of low dose (isotopes of iodine (125I), palladium (103Pd) and cesium (131Cs) and sources used for high dose rate (iridium Ir192 or cobalt 60 Co). In Russia the greatest popularity is the use of isotope Ir192 andI125 for brachytherapy. Given indentichnost the indications for treatment, equivalent figures cancerspecifically and relapse-free survival, the question of the choice of treatment is very important. A brief review of the literature on the use of brachytherapy for prostate cancer sources of different dose. Presents comparative characteristics of treatment results, complications, early and late toxic reactions when used brachytherapy isotopes different dose.

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14

Palmer, W. Neil, and Paul J. Chirik. "Cobalt-Catalyzed Stereoretentive Hydrogen Isotope Exchange of C(sp3)–H Bonds." ACS Catalysis 7, no. 9 (August 2, 2017): 5674–78. http://dx.doi.org/10.1021/acscatal.7b02051.

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15

Nakajima, Hideo, Shunya Ishioka, and Masahiro Koiwa. "Isotope effect for diffusion of cobalt in single-crystal α-titanium." Philosophical Magazine A 52, no. 6 (December 1985): 743–51. http://dx.doi.org/10.1080/01418618508242139.

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16

Bleaney, B., and O. V. Lounasmaa. "Nuclear orientation and nuclear cooling experiements in Oxford and Helsinki Part 2. Progress from 1945 to 1970." Notes and Records of the Royal Society of London 57, no. 3 (September 22, 2003): 323–30. http://dx.doi.org/10.1098/rsnr.2003.0218.

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The development of electron magnetic resonance by E. Zavoisky in 1945–46, and the discovery of hyperfine structure in paramagnetic compounds, soon found applications in cryogenics. Methods suggested for nuclear orientation were followed by experiments on magnetic alignment with the use of the radioactive isotope cobalt–60. These showed that the principles of both parity and charge conjugation are violated. Nuclear cooling reached microkelvin temperatures. † Deceased.

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17

Johnson, C. A., A. A. Bookstrom, and J. F. Slack. "Sulfur, Carbon, Hydrogen, and Oxygen Isotope Geochemistry of the Idaho Cobalt Belt." Economic Geology 107, no. 6 (September 1, 2012): 1207–21. http://dx.doi.org/10.2113/econgeo.107.6.1207.

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18

Wendling, Laura A., Jason K. Kirby, and Michael J. McLaughlin. "A Novel Technique to Determine Cobalt Exchangeability in Soils Using Isotope Dilution." Environmental Science & Technology 42, no. 1 (January 2008): 140–46. http://dx.doi.org/10.1021/es071526n.

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19

Hossain, M. Khalid, Hajime Tamura, and Kenichi Hashizume. "Visualization of hydrogen isotope distribution in yttrium and cobalt doped barium zirconates." Journal of Nuclear Materials 538 (September 2020): 152207. http://dx.doi.org/10.1016/j.jnucmat.2020.152207.

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20

Tannenbaum, Rina, and György Bor. "Isotope Effects in the Hydroformylation of Olefins with Cobalt Carbonyls as Catalysts." Journal of Physical Chemistry A 108, no. 34 (August 2004): 7105–11. http://dx.doi.org/10.1021/jp048353y.

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21

Bakkaus, Estelle, Richard N. Collins, Jean-Louis Morel, and Barbara Gouget. "Potential phytoavailability of anthropogenic cobalt in soils as measured by isotope dilution techniques." Science of The Total Environment 406, no. 1-2 (November 2008): 108–15. http://dx.doi.org/10.1016/j.scitotenv.2008.07.042.

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22

Qi, Yanying, Jia Yang, Xuezhi Duan, Yi-An Zhu, De Chen, and Anders Holmen. "Discrimination of the mechanism of CH4 formation in Fischer–Tropsch synthesis on Co catalysts: a combined approach of DFT, kinetic isotope effects and kinetic analysis." Catal. Sci. Technol. 4, no. 10 (2014): 3534–43. http://dx.doi.org/10.1039/c4cy00566j.

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23

Tombers, Matthias, Lars Barzen, and Gereon Niedner-Schatteburg. "Inverse H/D Isotope Effects in Benzene Activation by Cationic and Anionic Cobalt Clusters." Journal of Physical Chemistry A 117, no. 6 (January 23, 2013): 1197–203. http://dx.doi.org/10.1021/jp305281m.

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24

Beer, Bernhard, and Klaus G. Heumann. "Isotope dilution mass spectrometry of microelectronically relevant heavy metal traces in high-purity cobalt." Fresenius' Journal of Analytical Chemistry 347, no. 8-9 (1993): 351–55. http://dx.doi.org/10.1007/bf00323819.

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25

Zhong, Ming, Dai Tang, Bryan A. Webler, and Petrus C. Pistorius. "Interfacial Reaction Rate Constant of Nitrogen with Liquid Cobalt Measured by Nitrogen Isotope Exchange." Metallurgical and Materials Transactions B 52, no. 2 (February 23, 2021): 594–97. http://dx.doi.org/10.1007/s11663-021-02100-1.

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26

Itoh, Toshio, Hideo Nakajima, Y. Nakamura, M. Koiwa, and S. Yamaguchi. "Self-Diffusion and Isotope Effect of Cobalt in Intermetallic Compound Co₃Ti." Defect and Diffusion Forum 66-69 (January 1991): 509–14. http://dx.doi.org/10.4028/www.scientific.net/ddf.66-69.509.

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27

Evilia, Ronald F., and Martin Saunders. "An NMR Spectroscopic Determination of an Equilibrium Isotope Effect on the Hydration of Cobalt(II)." Spectroscopy Letters 18, no. 2 (March 1985): 105–14. http://dx.doi.org/10.1080/00387018508062215.

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28

Colter, Allan K., A. Gregg Parsons, and Karen Foohey. "Hydride transfer reactions. A kinetic study of oxidation of 10-methyl-9-phenylacridan by some π acceptors and a one-electron oxidant." Canadian Journal of Chemistry 63, no. 8 (August 1, 1985): 2237–40. http://dx.doi.org/10.1139/v85-368.

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The kinetics of oxidation of 10-methyl-9-phenylacridan (1(H)) and 9-deuterio-10-methyl-9-phenylacridan (1(D)) to 10-methyl-9-phenylacridinium ion (3) by eight oxidants have been investigated. The oxidants included the π-acceptors 1,4-benzoquinone (BQ), 7,7,8,8-tetracyanoquinodimethane (TCNQ), p-bromanil (BA), p-chloranil (CA), tetracyanoethylene (TCNE), 2,3-dicyano-1,4-benzoquinone (DCBQ) and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in acetonitrile (AN), BQ in 50:50 (v/v) AN-water, and the one-electron oxidant tris(2,2′-bipyridyl)cobalt(III), [Formula: see text] in AN. The seven π acceptors cover a 109-fold range of reactivity from BQ to DDQ and the deuterium kinetic isotope effect varies from 11.9 (BQ in AN) to 5.8 (DDQ). For π acceptors (BQ, TCNQ, CA, TCNE, and DCBQ) previously investigated with 10-methylacridan (NMA), 1(H) is less reactive than NMA by factors ranging from 9.1 (BQ) to 1.7 × 102 (TCNE). The isotope effects and relative reactivities for the π acceptor oxidations are most simply explained by a one-step hydride transfer mechanism.

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29

Diac, Madalina, Anton Knieling, Simona Irina Damian, Diana Bulgaru Iliescu, Ion Sandu, Cristina Furnica, Catalin Jan Iov, and Sofia David. "Forensic Aspects in Polonium-210 Poisoning." Revista de Chimie 68, no. 11 (December 15, 2017): 2646–49. http://dx.doi.org/10.37358/rc.17.11.5946.

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The human body is exposed to radiation resulting from the presence and degradation in the environment of natural radionuclides like uranium and thorium. In laboratories, several radioactive isotopes are being used: uranium-235, iodine-131, cobalt-60, and carbon-14. These radioactive isotopes are useful in scientific (dating human skeletal remains) and medical purposes (radiotherapy/radiodiagnosis), but they are also used in criminal context. Polonium 210 (Po-210) is a natural radioisotope occurring in the natural environment as consequence of uraniu-238 decay chain. The current paper presents a less known subject of lethal poisoning with Po-210 radioisotope, in order to underline the methods used for Po-210 identification in forensic samples. The authors performed a literature review of the scientific researchers published in the last years concerning polonium sources and its use as a poison. Polonium�s effectiveness as a poison relies on its chemical characteristics only to the extent that they determine the isotope�s distribution and retention in organs and tissues; the alpha particles are responsible for the lethal effect. Po-210 poisoning is particular, as it doesn�t leave traces, it can be easily transported, and is not detected by airport scanners. Identifying this compound during a medico-legal autopsy is very difficult, as the post-mortem examination will not yield characteristic aspects, the forensic pathologist being forced to consider this as a potential cause of a rapid death, with significant visceral damage.

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30

Allen, Lindsay Helen. "Bioavailability of Vitamin B12." International Journal for Vitamin and Nutrition Research 80, no. 45 (October 1, 2010): 330–35. http://dx.doi.org/10.1024/0300-9831/a000041.

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Vitamin B12 deficiency is common in people of all ages who consume a low intake of animal-source foods, including populations in developing countries. It is also prevalent among the elderly, even in wealthier countries, due to their malabsorption of B12 from food. Several methods have been applied to diagnose vitamin B12 malabsorption, including Schillings test, which is now used rarely, but these do not quantify percent bioavailability. Most of the information on B12 bioavailability from foods was collected 40 to 50 years ago, using radioactive isotopes of cobalt to label the corrinoid ring. The data are sparse, and the level of radioactivity required for in vivo labeling of animal tissues can be prohibitive. A newer method under development uses a low dose of radioactivity as 14C-labeled B12, with measurement of the isotope excreted in urine and feces by accelerator mass spectrometry. This test has revealed that the unabsorbed vitamin is degraded in the intestine. The percent bioavailability is inversely proportional to the dose consumed due to saturation of the active absorption process, even within the range of usual intake from foods. This has important implications for the assessment and interpretation of bioavailability values, setting dietary requirements, and interpreting relationships between intake and status of the vitamin.

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31

Andersen, Tom, and Hans-Fredrik Grorud. "Age and lead isotope systematics of uranium-enriched cobalt mineralization in the Modum complex, South Norway." Precambrian Research 91, no. 3-4 (August 1998): 419–32. http://dx.doi.org/10.1016/s0301-9268(98)00061-8.

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32

Klein, Hans-F., Herbert Beck, Birgit Hammerschmitt, Udo Koch, Susanne Koppert, Gerhard Cordier, and Helmut Paulus. "Synthesis, Properties, and Structure of a Dinitrogen Bridged Dinuclear Hydridocobalt Complex and its Reactions with 1-Alkynes." Zeitschrift für Naturforschung B 46, no. 2 (February 1, 1991): 147–56. http://dx.doi.org/10.1515/znb-1991-0204.

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Dinitrogen bridged cobalt(I) hydride compounds (L3CoH)2 N 2 (1: L = PMe3, 2: 3L = CH3C(CH2PMe2)3 have been synthesized by protonation of dinitrogen cobaltates. 1 crystallizes in the monoclinic space group C 2/m . a = 965, b = 1653, c = 1148 pm ,β = 106.88°, Z = 2. In solution 1 takes up N 2 reversibly forming CoH(N2)(PMe3)3 (1 a) . Infrared data including isotope labeling (15N , 2H) and assignment of vN = N and vCoH bands are presented. 1 reacts with aryl alkynes to give dialkynylcobalt(III) complexes CoH(C2,R1)(C2,R2)(PMe3)3 (5: R 1 = R 2 = C6H5; 6 : R 1 = R 2 = 4 -CH3C6H4; 7: R 1 = R 2 = 4-C lC 6 H 4; 8 : R 1 = C 6 H 5, R 2 = 4-ClC6H4) that are also obtained in a more convenient synthesis involving cobalt(I) intermediates Co(C2R1)(PMe3)4 (10: R 1 = 4 -CH3C6H4, 11: R 1 = 4-ClC6H4). Three metastable isomers of 5 have been characterized, the stable configuration is mer-trans as shown by a crystal structure determination: Space group P 21, a = 933.5(5), b = 1636.7(6), c = 901.1(3) pm, β = 97.4(1)°, Z = 2.

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33

Panneerselvam, K., A. W. Macfarlane, and V. J. M. Salters. "Reconnaissance Lead Isotope Characteristics of the Blackbird Deposit: Implications for the Age and Origin of Cobalt-Copper Mineralization in the Idaho Cobalt Belt, United States." Economic Geology 107, no. 6 (September 1, 2012): 1177–88. http://dx.doi.org/10.2113/econgeo.107.6.1177.

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34

Gnanamani, Muthu Kumaran, Gary Jacobs, Wilson D. Shafer, Dennis Sparks, and Burtron H. Davis. "Fischer–Tropsch Synthesis: Deuterium Kinetic Isotope Study for Hydrogenation of Carbon Oxides Over Cobalt and Iron Catalysts." Catalysis Letters 141, no. 10 (August 9, 2011): 1420–28. http://dx.doi.org/10.1007/s10562-011-0673-4.

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35

Meija, Juris, Tyler B. Coplen, Michael Berglund, Willi A. Brand, Paul De Bièvre, Manfred Gröning, Norman E. Holden, et al. "Atomic weights of the elements 2013 (IUPAC Technical Report)." Pure and Applied Chemistry 88, no. 3 (March 1, 2016): 265–91. http://dx.doi.org/10.1515/pac-2015-0305.

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AbstractThe biennial review of atomic-weight determinations and other cognate data has resulted in changes for the standard atomic weights of 19 elements. The standard atomic weights of four elements have been revised based on recent determinations of isotopic abundances in natural terrestrial materials: cadmium to 112.414(4) from 112.411(8),molybdenum to 95.95(1) from 95.96(2),selenium to 78.971(8) from 78.96(3), andthorium to 232.0377(4) from 232.038 06(2).The Commission on Isotopic Abundances and Atomic Weights (ciaaw.org) also revised the standard atomic weights of fifteen elements based on the 2012 Atomic Mass Evaluation: aluminium (aluminum) to 26.981 5385(7) from 26.981 5386(8),arsenic to 74.921 595(6) from 74.921 60(2),beryllium to 9.012 1831(5) from 9.012 182(3),caesium (cesium) to 132.905 451 96(6) from 132.905 4519(2),cobalt to 58.933 194(4) from 58.933 195(5),fluorine to 18.998 403 163(6) from 18.998 4032(5),gold to 196.966 569(5) from 196.966 569(4),holmium to 164.930 33(2) from 164.930 32(2),manganese to 54.938 044(3) from 54.938 045(5),niobium to 92.906 37(2) from 92.906 38(2),phosphorus to 30.973 761 998(5) from 30.973 762(2),praseodymium to 140.907 66(2) from 140.907 65(2),scandium to 44.955 908(5) from 44.955 912(6),thulium to 168.934 22(2) from 168.934 21(2), andyttrium to 88.905 84(2) from 88.905 85(2).The Commission also recommends the standard value for the natural terrestrial uranium isotope ratio, N(238U)/N(235U)=137.8(1).

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Landis, G. P., and A. H. Hofstra. "Ore Genesis Constraints on the Idaho Cobalt Belt from Fluid Inclusion Gas, Noble Gas Isotope, and Ion Ratio Analyses." Economic Geology 107, no. 6 (September 1, 2012): 1189–205. http://dx.doi.org/10.2113/econgeo.107.6.1189.

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Barge, T., P. Gas, and F. M. d'Heurle. "Analysis of the diffusion controlled growth of cobalt silicides in bulk and thin film couples." Journal of Materials Research 10, no. 5 (May 1995): 1134–45. http://dx.doi.org/10.1557/jmr.1995.1134.

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The solid state reaction between Co and Si has been studied in bulk diffusion couples between 850 and 1100 °C. At the scale of the observations made, the three phases Co2Si, CoSi, and CoSi2 are found to grow simultaneously, according to diffusion controlled kinetics. The results are analyzed in term of the Nernst-Einstein equation that directly relates diffusion fluxes to the free energy changes driving the formation. The growth rates obtained for CoSi2 at high temperatures, in the present bulk samples, are compared with those determined by others in thin films, at much lower temperatures. The comparison requires that attention should be paid to two factors. The first one is that the laws of growth are slightly different for a phase growing simultaneously with two other ones (bulk) and one phase growing alone (thin films). The second factor is the grain size of the various samples, which varies with the temperature of reaction. Once this is done, excellent agreement is obtained between the two sets of measurements. Moreover it is shown that knowing the grain size, it is possible to calculate quite accurately the growth rate from the respective isotope diffusion coefficients both for lattice and grain boundaries of Co and Si in CoSi2.

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Kerrich, R., D. F. Strong, A. J. Andrews, and L. Owsiacki. "The silver deposits at Cobalt and Gowganda, Ontario. III: Hydrothermal regimes and source reservoirs–evidence from H, O, C, and Sr isotopes and fluid inclusions." Canadian Journal of Earth Sciences 23, no. 10 (October 1, 1986): 1519–50. http://dx.doi.org/10.1139/e86-145.

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The Ag–, Co–Ni–sulpharsenide deposits of the Cobalt–Gowganda district are characterized by relatively uniform light-stable-isotope systematics, where δ18O in quartz spans 11.1–16.0‰; in K-feldspar, 10.1–12.3‰; in albite, 8.1–14.4‰; in actinolite, 6.0–7.6‰; in chlorite, 3.2–5.6‰; and δD in chlorite = −42 to −35‰. The temperature of hydrothermal silicate deposition was 150–230 °C, as calculated from Δquartz–chlorite, and triple to quadruple isotopic concordancy is locally preserved amongst quartz, chlorite, actinolite, and K-feldspar or albite. Filling temperature modes at 230 and 330 °C exist for primary inclusions in quartz and carbonates. Ore-forming hydrothermal fluids were isotopically characterized by δ18O = −2.5 to + 5‰, δD = −40 to + 5‰, interpreted to reflect isotopically and chemically evolved formation brines from Huronian aquifers, ultimately derived from marine pore fluids, and Proterozoic meteoric water recharge of the sedimentary basin. The restricted range of δ18Oquartz, Δquartz−chlorite, and δDchlorite from a large population of veins implies that the ore-forming fluids were tapped from a large reservoir, or reservoirs, relatively uniform with respect to temperature, δ18O, and δD.Quartzes in silicate selvages, wall rocks, and carbonate-dominated gangue are isotopically comparable, signifying fluid-dominated conditions and the initial precipitation of carbonates from fluids isotopically similar to those involved in the silicate stage and at comparable temperatures. Vein dolomites (δ18O = 21 to 23.1‰) continued to exchange down to temperatures of 110–140 °C in the presence of fluids where δ18O = 3 ± 2‰, during thermal attenuation of the ore-forming reservoir. Vein calcites (δ18O = 1.7 to 15.7‰) record late incursion of meteoric waters where δ18O = −8 to −22‰ at temperatures of ~50 °C. The population of vein carbonates clusters at δ13C = −3.1 to −5.3‰, and this is probably also close to the carbon-isotope signature of the hydrothermal fluid. The source of carbon is uncertain.Actinolites possess age-corrected 87Sr/86Sr = 0.715 to 0.729, for 2200 Ma, close to estimates for the contemporaneous Huronian ratio (0.7053–0.714) but more radiogenic than contemporaneous Archean volcanics (0.7017–0.7021) or the Nipissing diabase (0.7060–0.7061). On this basis, Sr is interpreted to have been derived principally from the Huronian sedimentary reservoir.Fluid inclusions in quartz and calcite of both mineralized and barren veins in the Cobalt and Gowganda mining camps and environs show five different types type I (L), type II (L + halite), type III (L + V), type IV (L + V + H), and type V (V), with types III and IV being most abundant. A histogram of all mine data shows modes around 100, 230, and 330 °C, with a range from > 560 to < 100 °C. No carbon dioxide was observed in the inclusions, although the dominance of calcite and dolomite in the veins attests to its presence during mineralization. Several samples show evidence of aqueous boiling, allowing a direct pressure determination of about 600 bar (60 MPa). The fluids were highly saline NaCl–CaCl2 brines, with up to 54 wt.% NaCl equivalent and highly variable Na/Ca ratios. Fluid inclusions in samples of barren veins from Lundy Township, outside the areas of known mineralization, do not appear to be significantly different from those of the mineralized veins, indicating that the hydrothermal fluids were active throughout a large area of the Huronian basin; this is corroborated by the disturbance of Pb- and Sr-isotope systems in the Nipissing, Huronian, and Archean.The Nipissing diabase likely served as a heat source to mobilize metals and advect formation brines, which may have derived the metals from either or all of the Huronian sediments or the Archean volcanics Nipissing diabase and sedimentary rocks. We suggest a genetic scheme for the veins involving CO2 effervescence and aqueous boiling inducing pH increase and thereby mediating rapid precipitation of ore minerals coeval with and followed by carbonates. This process explains most of the presently known major and minor characteristics of the vein systems and their host rocks, including the chloritic and sodic metasomatism of the Archean and Huronian rocks, abundant calcite, the compositional and mineralogical variability of the ore minerals, the textural variability of both the carbonates and ore minerals, the paragenetic sequence of alteration and mineralization, the distribution of ore minerals with respect to the diabase and other rocks, the relatively narrow vertical extent of mineralization, variations in ore grade and tonnage, and the distribution of economic deposits on the periphery of the Huronian basin.

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Burlinson, K. "ORE GENESIS CONSTRAINTS ON THE IDAHO COBALT BELT FROM FLUID INCLUSION GAS, NOBLE GAS ISOTOPE, AND ION RATIO ANALYSES--A DISCUSSION." Economic Geology 108, no. 5 (June 7, 2013): 1211–12. http://dx.doi.org/10.2113/econgeo.108.5.1211.

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Hofstra, A. H., and G. P. Landis. "ORE GENESIS CONSTRAINTS ON THE IDAHO COBALT BELT FROM FLUID INCLUSION GAS, NOBLE GAS ISOTOPE, AND ION RATIO ANALYSES--A REPLY." Economic Geology 108, no. 5 (June 7, 2013): 1213–14. http://dx.doi.org/10.2113/econgeo.108.5.1213.

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41

Acosta-Góngora, P., S. A. Gleeson, I. M. Samson, L. Corriveau, L. Ootes, B. E. Taylor, R. A. Creaser, and K. Muehlenbachs. "Genesis of the Paleoproterozoic NICO iron oxide–cobalt–gold–bismuth deposit, Northwest Territories, Canada: Evidence from isotope geochemistry and fluid inclusions." Precambrian Research 268 (October 2015): 168–93. http://dx.doi.org/10.1016/j.precamres.2015.06.007.

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Barzen, Lars, Matthias Tombers, Christine Merkert, Joachim Hewer, and Gereon Niedner-Schatteburg. "Benzene activation and H/D isotope effects in reactions of mixed cobalt platinum clusters: The influence of charge and of composition." International Journal of Mass Spectrometry 330-332 (December 2012): 271–76. http://dx.doi.org/10.1016/j.ijms.2012.09.008.

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43

Long, Pham Van, Gaston Giuliani, Anthony E. Fallick, Andrian J. Boyce, and Vincent Pardieu. "Trace elements and oxygen isotopes of gem spinels in marble from the Luc Yen - An Phu areas, Yen Bai province, North Vietnam." VIETNAM JOURNAL OF EARTH SCIENCES 40, no. 2 (May 19, 2018): 165–77. http://dx.doi.org/10.15625/0866-7187/40/2/12241.

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Trace elements investigated by electron microprobe analysis (EMPA) have been combined with oxygen isotopic composition of pink, red and other colored spinels (blue, purple, brown, orange, lavender) hosted by marbles and found in placers from Luc Yen and An Phu deposits, Yen Bai province, North Vietnam. The deposits are those from Nuoc Ngap, Cong Troi, Bai Son and different placers from the An Phu area. Trace elements such as Fe-Zn-Cr-V in red and pink gem spinels permit to separate those from Cong Troi and those from the others deposits of the An Phu area. Spinels from Cong Troi have low to extremely low Zn (< 500 ppm) and high Fe contents (3,000 to 16,000 ppm) while those from An Phu area are Zn-rich (up to 11,000 ppm). Iron is the dominant element for the other colored spinels whereas Zn, Cr and V contents are extremely variable. The Bai Son blue spinel is Fe-rich (5,000 to 7,200 ppm) with some V (950 to 1,830 ppm), Cr (270 to 480 ppm), Co (240 to 400 ppm) and Ni (550 to 950 ppm). The O-isotope composition of the whole spinels ranges between 12.1 and 24.2‰ (n = 25). Within each deposit, the range of δ18O values for red, pink and colored spinels is usually similar. However, the red and pink spinels from An Phu present two distinct sets of δ18O values, respectively between 13.2 to 17.0‰ (n = 7) and 22.5< δ18O < 24.2 (n = 5). Those from Cong Troi are from 14.8 to 17.7‰ (n = 3) and their range overlaps that of An Phu. The use of O-isotopes is not useful for distinguishing between the deposits, but the low to extremely low Zn content of the Cong Trois spinels is a discriminant. The variation of δ18O values (12.1 <δ18O < 24.2‰) of the whole spinels indicates that the oxygen isotopic compositions of the metamorphic fluids were probably buffered by the local δ18O values of the impure host marbles.ReferencesChauviré B., Rondeau B., Fritsch E., Ressigeac Ph., Devidal J.-L., 2015. Blue spinel from the Luc Yen district of Vietnam. Gems & Gemology, 51, 2-17.D'Ippolito V., Andreozzi G.B., Hålenius H., Skogby H., Hametner K., Günther D., 2015. Colour mechanisms in spinel: cobalt and iron interplay for the blue colour. Physics and Chemistry of Minerals, 42, 431-439.Garnier V., 2003. Les gisements de rubis associés aux marbres de l’Asie Centrale et du Sud-est: genèse et caractérisation isotopique. PhD thesis INPL, Nancy, France, 373p.Garnier, V., Ohnenstetter, D., Giuliani, G., Maluski, H., Deloule, E., Phan Trong Trinh, Pham Van Long, Hoang Quang Vinh, 2005. Age and significance of ruby-bearing marbles from the Red River shear zone, northern Vietnam. The Canadian Mineralogist, 43, 1315-1329.Garnier V., Giuliani G., Ohnenstetter D., Fallick A.E., Dubessy J., Banks D., Hoang Quang Vinh, Lhomme Th., Maluski H., Pêcher A., Bakhsh K.A., Pham Van Long, Phan Trong Trinh, Schwarz D., 2008. Marble-hosted ruby deposits from central and Southeast Asia: towards a new genetic model. Ore Geology Reviews, 34, 169-191.Giuliani G., Fallick A.E., Garnier V., France-Lanord Ch., Ohnenstetter D., Schwarz D., 2005. Oxygen isotope composition as a tracer for the origins of rubies and sapphires. Geology, 33(4), 249-252.Giuliani G., Fallick A.E., Boyce A.J., Pardieu V., Pham Van Long, 2017. Pink and red spinels in marble: trace elements, oxygen isotopes, and sources. The Canadian Mineralogist, 55, 743-761.Hauzenberger C.A., Häeger T., Baumgartner L.P., Hofmeister W., 2001. High-grade metamorphism and stable isotope geochemistry of N-Vietnamese gem-bearing rocks. In: Proceedings of the Workshop on gems and minerals of Vietnam, Hanoi, 124-138.Hauzenberger C.A., Bagola C., Häeger T., Muellen C., Nguyen Ngoc Khoi, Le Thi Thu Huong, 2014. Mineralogy and petrology of the An Phu marble hosted spinel and corundum deposit, Luc Yen, N-Vietnam. In Proceedings of the 4th International Gem and Jewelry Conference, Chiang Mai, Thailand, 76-78.Kleišmantas A., Daukšyte A., 2016. The influence of Vietnam and Sri Lanka spinel mineral chemical elements on colour. Chemija, 27, 45-51.Kretz R., 1983. Symbols for rock-forming minerals. American Mineralogist, 68, 277-279.Le Thi Thu Huong, Häeger T., Hofmeister W., Hauzenberger C., Schwarz D., Pham Van Long, Wehmeister U., Nguyen Ngoc Khoi, Nguy Tuyet Nhung, 2012. Gemstones from Vietnam: An update. Gems & Gemology, 48, 158-176.Malsy A., Klemm L., 2010. Distinction of gem spinels from the Himalayan mountain belt. Chimia, 64(10), 741-746.Malsy A., Karampelas S., Schwarz D., Klemm L., Armbruster T., Tuan Do Anh, 2012. Orangey-red to orangey-pink gem spinels from a new deposit at Lang Chap (Tan Huong - Truc Lau), Vietnam. The Journal of Gemmology, 33, 19-27.Pham Van Long, Hoang Quang Vinh, Garnier V., Giuliani G., Ohnenstetter D., Lhomme,T., Schwarz D., Fallick A.E., Dubessy J., Phan Trong Trinh, 2004. Gem corundum deposits in Vietnam. Journal of Gemmology, 29, 129-147.Pham Van Long, Pardieu V., Giuliani G., Nguy Tuyet Nhung, Pham Thi Thanh Hien, Pham Duc Anh, Nguyen Ngoc Khoi, Hoang Quang Vinh, 2014. Gemmological characteristics of spinel from Luc Yen, Yen Bai. Journal of Geology, 340, 29-36.Pham Van Long, Pardieu V., Giuliani G., 2014. Update on gemstone mining in Luc Yen, Vietnam. Gems & Gemology, 49, 233-245.Pouchou J.L., Pichoir F., 1991. Quantitative analysis of homogeneous or stratified microvolumes applying "PAP" In Electron Probe Quantification (K.F.J. Heinrich & D.E. Newbury eds.). Plenum Press, New York, USA, 31-75.Valley J.W., 1986. Stable isotope geochemistry of metamorphic rocks. Reviews in Mineralogy, 16, 445-481.Yui T.F., Khin Zaw, Wu C.-M., 2008. A preliminary stable isotope study on Mogok ruby, Myanmar. Ore Geology Reviews, 34, 182-199.

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Rinne, Sara S., Charles Dahlsson Leitao, Zahra Saleh-nihad, Bogdan Mitran, Vladimir Tolmachev, Stefan Ståhl, John Löfblom, and Anna Orlova. "Benefit of Later-Time-Point PET Imaging of HER3 Expression Using Optimized Radiocobalt-Labeled Affibody Molecules." International Journal of Molecular Sciences 21, no. 6 (March 13, 2020): 1972. http://dx.doi.org/10.3390/ijms21061972.

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HER3-binding affibody molecules are a promising format for visualization of HER3 expression. Cobalt-55, a positron-emitting isotope, with a half-life of 17.5 h, allows for next-day imaging. We investigated the influence of the charge of the radiocobalt–chelator complex on the biodistribution of anti-HER3 affibody molecule (HE)3-ZHER3 and compared the best radiocobalt-labeled variant with a recently optimized gallium-labeled variant. Affibody conjugates (HE)3-ZHER3-X (X = NOTA, NODAGA, DOTA, DOTAGA) were labeled with [57Co]Co (surrogate for 55Co). Affinity measurements, binding specificity and cellular processing were studied in two HER3-expressing cancer cell lines. Biodistribution was studied 3 and 24 h post-injection (pi) in mice with HER3-expressing BxPC-3 xenografts and compared to [68Ga]Ga-(HE)3-ZHER3-NODAGA. Micro-single-photon emission tomography/computed tomography (microSPECT/CT) and micro-positron emission tomography/computed tomography (microPET/CT) imaging was performed 3 and 24 h pi. Stably labeled conjugates bound to HER3 with subnanomolar affinity. [57Co]Co-(HE)3-ZHER3-DOTA had the best tumor retention and a significantly lower concentration in blood than other conjugates, leading to superior tumor-to-blood and tumor-to-liver ratios 24 h pi. Compared to [68Ga]Ga-(HE)3-ZHER3-NODAGA 3 h pi, [57Co]Co-(HE)3-ZHER3-DOTA provided superior imaging contrast in liver 24 h pi. Concluding, the composition and charge of the [57Co]Co–chelator complex influenced the uptake in tumors and normal tissue. [57Co]Co-(HE)3-ZHER3-DOTA provided the best imaging properties among the cobalt-labeled conjugates. Delayed imaging of HER3 expression with [57Co]Co-(HE)3-ZHER3-DOTA improved imaging contrast compared to early-time-point imaging with [68Ga]Ga-(HE)3-ZHER3-NODAGA.

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Yashiro, Morio, Shigenobu Yano, and Sadao Yoshikawa. "Isotopic multiplets in the carbon-13 NMR spectra of cobalt(III) complexes with partially deuterated coordinated amino or imino groups. Dihedral angular dependence of the three-bond isotope effects." Journal of the American Chemical Society 108, no. 5 (March 1986): 1096–97. http://dx.doi.org/10.1021/ja00265a049.

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Potter, E. G., and R. P. Taylor. "THE LEAD ISOTOPE COMPOSITION OF ORE MINERALS FROM PRECIOUS METAL-BEARING, POLYMETALLIC VEIN SYSTEMS IN THE COBALT EMBAYMENT, NORTHERN ONTARIO: METALLOGENETIC IMPLICATIONS." Economic Geology 104, no. 6 (September 1, 2009): 869–79. http://dx.doi.org/10.2113/gsecongeo.104.6.869.

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Yang, Jia, Erik Z. Tveten, De Chen, and Anders Holmen. "Understanding the Effect of Cobalt Particle Size on Fischer−Tropsch Synthesis: Surface Species and Mechanistic Studies by SSITKA and Kinetic Isotope Effect†." Langmuir 26, no. 21 (November 2, 2010): 16558–67. http://dx.doi.org/10.1021/la101555u.

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48

Weststrate, C. J., and J. W. Niemantsverdriet. "Understanding FTS selectivity: the crucial role of surface hydrogen." Faraday Discussions 197 (2017): 101–16. http://dx.doi.org/10.1039/c6fd00191b.

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Monomeric forms of carbon play a central role in the synthesis of long chain hydrocarbons via the Fischer–Tropsch synthesis (FTS). We explored the chemistry of C₁H_xad species on the close-packed surface of cobalt. Our findings on this simple model catalyst highlight the important role of surface hydrogen and vacant sites for product selectivity. We furthermore find that CO_ad affects hydrogen in multiple ways. It limits the adsorption capacity for H_ad, lowers its adsorption energy and inhibits dissociative H₂ adsorption. We discuss how these findings, extrapolated to pressures and temperatures used in applied FTS, can provide insights into the correlation between partial pressure of reactants and product selectivity. By combining the C₁H_x stability differences found in the present work with literature reports of the reactivity of C₁H_x species measured by steady state isotope transient kinetic analysis, we aim to shed light on the nature of the atomic carbon reservoir found in these studies.

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Machi, Sueo. "Trends for Electron Beam Accelerator Applications in Industry." Reviews of Accelerator Science and Technology 04, no. 01 (January 2011): 1–10. http://dx.doi.org/10.1142/s1793626811000562.

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Electron beam (EB) accelerators are major pieces of industrial equipment used for many commercial radiation processing applications. The industrial use of EB accelerators has a history of more than 50 years and is still growing in terms of both its economic scale and new applications. Major applications involve the modification of polymeric materials to create value-added products, such as heat-resistant wires, heat-shrinkable sheets, automobile tires, foamed plastics, battery separators and hydrogel wound dressing. The surface curing of coatings and printing inks is a growing application for low energy electron accelerators, resulting in an environmentally friendly and an energy-saving process. Recently there has been the acceptance of the use of EB accelerators in lieu of the radioactive isotope cobalt-60 as a source for sterilizing disposable medical products. Environmental protection by the use of EB accelerators is a new and important field of application. A commercial plant for the cleaning flue gases from a coal-burning power plant is in operation in Poland, employing high power EB accelerators. In Korea, a commercial plant uses EB to clean waste water from a dye factory.

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Mukherjee, Indrani, Ross R. Large, Stuart Bull, Daniel G. Gregory, Aleksandr S. Stepanov, Janaína Ávila, Trevor R. Ireland, and Ross Corkrey. "Pyrite trace-element and sulfur isotope geochemistry of paleo-mesoproterozoic McArthur Basin: Proxy for oxidative weathering." American Mineralogist 104, no. 9 (September 1, 2019): 1256–72. http://dx.doi.org/10.2138/am-2019-6873.

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Abstract Redox-sensitive trace elements and sulfur isotope compositions obtained via in situ analyses of sedimentary pyrites from marine black shales are used to track atmosphere-ocean redox conditions between ∼1730 and ∼1360 Ma in the McArthur Basin, northern Australia. Three black shale formations within the basin (Wollogorang Formation 1730 ± 3 Ma, Barney Creek Formation 1640 ± 3 Ma, and Upper Velkerri Formation 1361 ± 21 Ma) display systematic stratigraphic variations in pyrite trace-element compositions obtained using LA-ICP-MS. The concentrations of several trace elements and their ratios, such as Se, Zn, Se/Co, Ni/Co, Zn/Co, Mo/Co, Se/Bi, Zn/Bi, Ni/Bi, increase from the stratigraphically lower Wollogorang Formation to the Upper Velkerri Formation. Cobalt, Bi, Mo, Cu, and Tl show a consistent decrease in abundance while Ni, As, and Pb show no obvious trends. We interpret these trace element trends as a response to the gradual increase of oxygen in the atmosphere-ocean system from ∼1730 to 1360 Ma. Elements more mobile during erosion under rising atmospheric oxygen show an increase up stratigraphy (e.g., Zn, Se), whereas elements that are less mobile show a decrease (e.g., Co, Bi). We also propose the increase of elemental ratios (Se/Co, Ni/Co, Zn/Co, Mo/Co, Ni/Bi, and Zn/Bi) up stratigraphy are strong indicators of atmospheric oxygenation. Sulfur isotopic compositions of marine pyrite (δ34Spyrite) from these formations, obtained using SHRIMP-SI, are highly variable, with the Wollogorang Formation exhibiting less variation (δ34S = –29.4 to +9.5‰; mean –5.03‰) in comparison to the Barney Creek (δ34S = –13.8 to +41.8‰; mean +19.88‰) and Velkerri Formations (δ34S = –14.2 to +52.8‰; mean +26.9‰). We propose that the shift in mean δ34S to heavier values up-section corresponds to increasing deep water oxygenation from ∼1730 to 1360 Ma. Incursion of oxygenated waters possibly caused a decrease in the areal extent of anoxic areas, at the same time, creating a possibly efficient reducing system. A stronger reducing system caused the δ34S of the sedimentary pyrites to become progressively heavier. Interestingly, heavy δ34S in pyrites overlaps with the increase in the concentration of certain trace elements (and their ratios) in sedimentary pyrites (Se, Zn, Se/Co, Ni/Co, Zn/Co, Mo/Co, Ni/Bi, and Zn/Bi). This study concludes that there was a gradual increase of atmospheric oxygen accompanied by ocean oxygenation through the first ∼400 million years of the Boring Billion (1800–1400 Ma) in the McArthur Basin.

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