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Showing 1 to 20 of 160 for “"Carbon Isotope"”.
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Carbon Isotope Effects: Malonic Acid Decarboxylation
Made available in DSpace on 2014-12-05T19:37:01Z (GMT). No. of bitstreams: 1 5900526.pdf: 3674148 bytes, checksum: 7b4988e9c0a6f505ce9e8dd72b26b4bd (MD5) Previous issue date: 1958
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Carbon Isotope Effect Studies of the Decarbonylation of Formic Acid
Made available in DSpace on 2014-12-05T19:36:44Z (GMT). No. of bitstreams: 1 0025225.pdf: 3702059 bytes, checksum: 40c1692e40197262edcb196e97f17941 (MD5) Previous issue date: 1957
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Carbon Isotope Effects in the Decarboxylation of Malonic Acid Vapor
Made available in DSpace on 2014-12-05T19:37:22Z (GMT). No. of bitstreams: 1 6001646.pdf: 3487741 bytes, checksum: bc4ce7161774b52e90b76ebaacd3b38f (MD5) Previous issue date: 1960
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Carbonatites as a record of the carbon isotope composition of large igneous province outgassing
… in some cases to major perturbations of Earth’s carbon cycle. However, few observations directly constrain the isotopic composition of carbon released by LIP magmas because carbon isotopes fractionate during degassing, which hampers understanding of the relative roles of mantle versus crustal …
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Carbon Cycling Dynamics Inferred from Carbon Isotope Sourcing in a Mid-Latitude Karst-Influenced River
<p>As ever-increasing levels of carbon dioxide alter the chemistry of the Earth’s atmosphere, understanding the global carbon cycle becomes increasingly important. A particularly important component is the riverine carbon cycle, as rivers are the primary conduits for dissolved inorganic carbon from …
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Precision measurement of carbon isotope ratio in exhaled breath for the detection of helicobacter pylori
… and this is conventionally done by using anIsotope Ratio Mass Spectrometer. However, the huge cost and complexity involved in operating these instruments has restricted their widespread use. A viable and low cost alternative is offered by instruments employing non-dispersive infrared …
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Evolution and ecology of C4 grasses: insights from carbon isotope analysis of grass pollen grains
… this limitation by utilizing Single Pollen Isotope Ratio AnaLysis (SPIRAL), a technique that reliably distinguishes C4 from C3 grasses in the fossil record via δ13C values of individual pollen grains. Before applying the technique to fossil samples, I refined the original SPIRAL method by …
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Carbon Isotope Effects in Malonic Acid Decarboxylation. I. Influence of Perdeuteration. Ii. The Ionization Effect
Made available in DSpace on 2014-12-09T17:34:48Z (GMT). No. of bitstreams: 1 6406093.pdf: 7747900 bytes, checksum: e5faf38c5cf92af6b31842662693a576 (MD5) Previous issue date: 1963
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Carbon isotope stratigraphy of the interglacial Umberatana Group, Adelaide, Fold Belt, South Australia / by Jamie M. Burgess.
… interbasin stratigraphic correlation based on C-isotope geochemistry. High data resolution is desirable and correlation should take into account lithostratigraphy and sequence stratigraphy rather than soley relying on data trends or absolute [delta]13C values.
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Western South Atlantic holocene and glacial deepwater hydrography derived from benthic foraminiferal Cd/Ca and stable carbon isotope data
Today, deep waters produced in the North Atlantic are exported through the western South Atlantic. Antarctic intermediate water AAJW also enters the Atlantic in this region. Circumpolar deep water (CDW) fills the depths below AAIW and above and below northern source waters. A depth transect of …
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Western South Atlantic holocene and glacial deepwater hydrography derived from benthic foraminiferal Cd/Ca and stable carbon isotope data
Today, deep waters produced in the North Atlantic are exported through the western South Atlantic. Antarctic intermediate water (AAIW) also enters the Atlantic in this region. Circumpolar deep water (CDW) fills the depths below AAIW and above and below northern source waters. A depth transect of …
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Carbonate Carbon Isotope Chemostratigraphy from the Ruby Ranch Member of the Cedar Mountain Formation in the Western San Rafael Swell
… gray silty-sandy mudstones with abundant carbonate nodules suggestive of paleosol development. For this study samples were collected approximately every 25 cm and were used to construct a C-isotope curve using carbonate carbon. These were used to compare to existing bulk sedimentary …
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Water-use efficiency, photosynthetic characteristics, and high through-put phenotyping methods for soybean (glycine max) genotypes contrasting in carbon isotope discrimination
… is for plants to use water more efficiently. Carbon isotope discrimination (CID) is a measured trait that is related to water-use efficiency (WUE), and can be used to screen genotypes for higher WUE. Several genotypes were studied in multiple greenhouse and field experiments with varying …
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The Application of Pedology, Stable Carbon Isotope Analyses and Geographic Information Systems to Ancient Soil Resource Investigations at Piedras Negras, Guatemala
… Maya mystery. Pedological studies and stable carbon isotope analysis of soil organic matter, combined with Geographic Information Systems (GIS) are three tools that can be used to answer crucial questions as to how the Maya managed their soil resources.</p> <p>GIS maps that indicated areas of …
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Use of carbon isotope and C/N geochemistry in reconstructing vegetation communities: a mid- to late- Holocene palaeoenvironmental investigation from Romney Marsh, Kent, UK
The use of stable carbon isotope geochemistry and C/N ratios for coastal palaeoenvironmental reconstructions is a relatively new and under-researched field. This research seeks to understand the processes which govern the carbon isotope and C/N ratios of past and present vegetation communities, …
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Terrestrial Impacts of the Central Atlantic Magmatic Province on western Pangea
… been associated with a disruption to the global carbon cycle due the emplacement of the Central Atlantic Magmatic Province (CAMP). Evidence has shown that this global carbon cycle perturbation may be the culprit for the end-Triassic extinction. The Whitmore Point Member of the Moenave Formation …
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The Biogeochemistry of Carbon Isotopes in Local Lakes
… of organic matter all involve the transfer of carbon among the carbon-bearing species in the systems. These biogeochemical processes also fractionate the carbon isotope composition, which results in changes to the carbon isotope composition of the dissolved inorganic carbon (DIC) pool. This …
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Differential Utilization of Allochthonous and Autochthonous Carbon By Aquatic Insects of Two Shrub-Steppe Desert Spring-Streams: A Stable Carbon Isotope Analysis and Critique of the Method
<p>Stable carbon isotope analysis, a technique that measures the ratio of stable carbon-12 to stable carbon-13 in abiotic and biotic components of ecosystems, was used to assess the differential utilization of autochthonous and allochthonous carbon by aquatic insects of two cold desert …
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