Academic literature on the topic 'Isotopes of carbon'

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Journal articles on the topic "Isotopes of carbon"

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Sare, David T. J., John S. Millar, and Frederick J. Longstaffe. "Tracing dietary protein in red-backed voles (Clethrionomys gapperi) using stable isotopes of nitrogen and carbon." Canadian Journal of Zoology 83, no. 5 (May 1, 2005): 717–25. http://dx.doi.org/10.1139/z05-064.

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We examined the stable isotopes of nitrogen and carbon in a small mammal, the red-backed vole (Clethroinomys gapperi (Vigors, 1830)), to determine if isotope signatures reflect diet composition. Nitrogen- and carbon-isotope ratios in tissues from voles maintained on different protein levels in the laboratory were compared with wild-trapped voles. The isotopic fractionation of dietary nitrogen and carbon was also examined as food was digested in the stomach, incorporated into bone collagen, bioapatite, and hair, and excreted as feces. Nitrogen and carbon isotopes were fractionated differently depending on the isotopic composition and protein content of the diet. δ15N and δ13C values appear to be influenced by factors in addition to diet, such as macronutrients metabolized for respiration, metabolic rate, and periods of protein shortage.
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Meister, Patrick, and Carolina Reyes. "The Carbon-Isotope Record of the Sub-Seafloor Biosphere." Geosciences 9, no. 12 (December 5, 2019): 507. http://dx.doi.org/10.3390/geosciences9120507.

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Sub-seafloor microbial environments exhibit large carbon-isotope fractionation effects as a result of microbial enzymatic reactions. Isotopically light, dissolved inorganic carbon (DIC) derived from organic carbon is commonly released into the interstitial water due to microbial dissimilatory processes prevailing in the sub-surface biosphere. Much stronger carbon-isotope fractionation occurs, however, during methanogenesis, whereby methane is depleted in 13C and, by mass balance, DIC is enriched in 13C, such that isotopic distributions are predominantly influenced by microbial metabolisms involving methane. Methane metabolisms are essentially mediated through a single enzymatic pathway in both Archaea and Bacteria, the Wood–Ljungdahl (WL) pathway, but it remains unclear where in the pathway carbon-isotope fractionation occurs. While it is generally assumed that fractionation arises from kinetic effects of enzymatic reactions, it has recently been suggested that partial carbon-isotope equilibration occurs within the pathway of anaerobic methane oxidation. Equilibrium fractionation might also occur during methanogenesis, as the isotopic difference between DIC and methane is commonly on the order of 75‰, which is near the thermodynamic equilibrium. The isotopic signature in DIC and methane highly varies in marine porewaters, reflecting the distribution of different microbial metabolisms contributing to DIC. If carbon isotopes are preserved in diagenetic carbonates, they may provide a powerful biosignature for the conditions in the deep biosphere, specifically in proximity to the sulphate–methane transition zone. Large variations in isotopic signatures in diagenetic archives have been found that document dramatic changes in sub-seafloor biosphere activity over geological time scales. We present a brief overview on carbon isotopes, including microbial fractionation mechanisms, transport effects, preservation in diagenetic carbonate archives, and their implications for the past sub-seafloor biosphere and its role in the global carbon cycle. We discuss open questions and future potentials of carbon isotopes as archives to trace the deep biosphere through time.
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Pollard, A. M. "Isotopes and impact: a cautionary tale." Antiquity 85, no. 328 (May 2011): 631–38. http://dx.doi.org/10.1017/s0003598x00068034.

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There can be no doubt that isotopic studies have made a huge contribution to archaeology in recent years, so much so that isotope archaeology is now seen as an essential subdiscipline of archaeology in much the same way as isotope geochemistry is a key subdiscipline of geochemistry. Ignoring for current purposes the contribution made by the measurement of a particular radioactive isotope of carbon (14C) since 1950, we can date the beginnings of isotope archaeology to the mid 1960s with the first measurements of lead isotopes in archaeological metals and slags by Brill and Wampler (1965, 1967). This was followed by carbon stable isotopes in human bone collagen in the late 1970s, building on previous work measuring σ13C in archaeological bone for radiocarbon determinations (Vogel & Van der Merwe 1977; Van der Merwe & Vogel 1978). Other isotopes followed rapidly, such as nitrogen, oxygen, sulphur and hydrogen for archaeological, palaeoecological or palaeoclimatological purposes and, more recently, the heavier radiogenic isotopes of strontium and neodymium for determining the provenance of organic and inorganic materials (Pollard & Heron 2008).
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Passey, Benjamin H. "Reconstructing Terrestrial Environments Using Stable Isotopes in Fossil Teeth and Paleosol Carbonates." Paleontological Society Papers 18 (November 2012): 167–94. http://dx.doi.org/10.1017/s1089332600002606.

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Carbon isotopes in Neogene-age fossil teeth and paleosol carbonates are commonly interpreted in the context of past distributions of C3 and C4 vegetation. These two plant types have very different distributions in relation to climate and ecology, and provide a robust basis for reconstructing terrestrial paleoclimates and paleoenvironments during the Neogene. Carbon isotopes in pre-Neogene fossil teeth are usually interpreted in the context of changes in the δ13C value of atmospheric CO2, and variable climate-dependent carbon-isotope discrimination in C3 plants. Carbon isotopes in pre-Neogene soil carbonates can be used to estimate past levels of atmospheric CO2. Oxygen isotopes in fossil teeth and paleosol carbonates primarily are influenced by the oxygen isotopic compositions of ancient rainfall and surface waters. The oxygen isotopic composition of rainfall is has a complex, but tractable, relationship with climate, and variably relates to temperature, elevation, precipitation amount, and other factors. Mammal species that rely on moisture in dietary plant tissues to satisfy their water requirements (rather than surface drinking water) may have oxygen isotopic compositions that track aridity. Thus, oxygen isotopes of fossil mammals can place broad constraints on paleoaridity. Carbonate clumped isotope thermometry allows for reconstruction of soil temperatures at the time of pedogenic carbonate mineralization. The method is unique because it is the only thermodynamically based isotopic paleothermometer that does not require assumptions about the isotopic composition of the fluid in which the archive mineral formed. Soil temperature reflects a complex interplay of air temperature, solar radiative heating, latent heat effects, soil thermal diffusivity, and seasonal variations of these parameters. Because plants and most animals live in and/or near the soil, soil temperature is an important aspect of terrestrial (paleo)climate.
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Arneson, Lynne S., Stephen MacAvoy, and Ethan Basset. "Metabolic protein replacement drives tissue turnover in adult mice." Canadian Journal of Zoology 84, no. 7 (July 1, 2006): 992–1002. http://dx.doi.org/10.1139/z06-081.

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Stable isotopes are increasingly being used to examine ecological and physiological questions, such as dietary choices, migration routes and timing, and physiological condition. To address these questions in the field, laboratory experiments must be done to determine diet–tissue discrimination values and turnover rates for stable isotopes in tissues. In this study, we examined the carbon and nitrogen turnover rates of whole blood, skeletal muscle, liver, kidney, heart, and brain, as well as the sulfur turnover rate of whole blood, skeletal muscle, and liver in Mus musculus L., 1758 following a diet change. By examining tissue isotope change in two groups of mice fed different diets, we found that tissues turnover at different rates (in order of fastest to slowest — liver, kidney, heart, brain, whole blood, skeletal muscle), but that carbon, nitrogen, and sulfur isotopes turned over with similar half-lives within a single tissue. By using a diet with different nutrient isotopic values, we also calculated that up to approximately 90%–95% of carbon in newly synthesized tissue was contributed by dietary protein. These results will provide field researchers with additional tissue isotopic half-lives to elucidate dietary history with a greater degree of certainty. The tissue sulfur half-lives provide an extra stable isotope that may be used in situations where carbon and nitrogen values do not differ between old and new nutrient sources.
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Erez, Jonathan, Anne Bouevitch, and Aaron Kaplan. "Carbon isotope fractionation by photosynthetic aquatic microorganisms: experiments with Synechococcus PCC7942, and a simple carbon flux model." Canadian Journal of Botany 76, no. 6 (June 1, 1998): 1109–18. http://dx.doi.org/10.1139/b98-067.

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Stable carbon isotopes (12C and 13C) are widely used to trace biogeochemical processes in the global carbon cycle. Natural fractionation of carbon isotopes is mainly due to the discrimination of ribulose-1,5-bisphosphate carboxylase-oxygenase (Rubisco) against 13C during photosynthesis. In marine and other aquatic microorganisms, this fractionation is lowered when the dissolved CO2 (CO2(aq)) is decreasing, but the underlying mechanisms are poorly understood. Cultured Synechococcus PCC7942 showed maximum isotopic fractionations of -33omicron (in delta 13C units) relative to the total inorganic carbon (Ci) when CO2(aq) is above 30 m M. As the culture grew, pH increased, CO2(aq) was lower than 1 m M, and the Ci concentrating mechanism was induced although the Ci was above 3 mM. The isotopic fractionation was drastically reduced to values of -1 to -3 omicron relative to Ci. A simple carbon isotope flux model suggests that during the first stages of the experiment the total uptake (F1) was roughly three- to four-fold greater than the photosynthetic net accumulation (F2). When the Ci concentrating mechanism was induced, the leakage of CO2 from the cells declined, the cells started to utilize HCO3- and the F1/F2 ratio decreased to values close to 1. Based on this model the isotopic variability of oceanic phytoplankton suggests that the F1/F2 ratio may be above 3 in high latitudes and ~1.1 in equatorial waters, where the Ci concentrating mechanism is probably induced. Attempts to reconstruct past atmospheric CO2 levels and paleoproductivity should take into account the effects of the Ci concentrating mechanism on the isotopic fractionation of aquatic primary producers.Key words: carbon concentrating mechanism, carbon isotope fractionation, CO2, photosynthesis.
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Bühler, Janica C., Josefine Axelsson, Franziska A. Lechleitner, Jens Fohlmeister, Allegra N. LeGrande, Madhavan Midhun, Jesper Sjolte, Martin Werner, Kei Yoshimura, and Kira Rehfeld. "Investigating stable oxygen and carbon isotopic variability in speleothem records over the last millennium using multiple isotope-enabled climate models." Climate of the Past 18, no. 7 (July 13, 2022): 1625–54. http://dx.doi.org/10.5194/cp-18-1625-2022.

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Abstract. The incorporation of water isotopologues into the hydrology of general circulation models (GCMs) facilitates the comparison between modeled and measured proxy data in paleoclimate archives. However, the variability and drivers of measured and modeled water isotopologues, as well as the diversity of their representation in different models, are not well constrained. Improving our understanding of this variability in past and present climates will help to better constrain future climate change projections and decrease their range of uncertainty. Speleothems are a precisely datable terrestrial paleoclimate archives and provide well-preserved (semi-)continuous multivariate isotope time series in the lower latitudes and mid-latitudes and are therefore well suited to assess climate and isotope variability on decadal and longer timescales. However, the relationships of speleothem oxygen and carbon isotopes to climate variables are influenced by site-specific parameters, and their comparison to GCMs is not always straightforward. Here we compare speleothem oxygen and carbon isotopic signatures from the Speleothem Isotopes Synthesis and Analysis database version 2 (SISALv2) to the output of five different water-isotope-enabled GCMs (ECHAM5-wiso, GISS-E2-R, iCESM, iHadCM3, and isoGSM) over the last millennium (850–1850 CE). We systematically evaluate differences and commonalities between the standardized model simulation outputs. The goal is to distinguish climatic drivers of variability for modeled isotopes and compare them to those of measured isotopes. We find strong regional differences in the oxygen isotope signatures between models that can partly be attributed to differences in modeled surface temperature. At low latitudes, precipitation amount is the dominant driver for stable water isotope variability; however, at cave locations the agreement between modeled temperature variability is higher than for precipitation variability. While modeled isotopic signatures at cave locations exhibited extreme events coinciding with changes in volcanic and solar forcing, such fingerprints are not apparent in the speleothem isotopes. This may be attributed to the lower temporal resolution of speleothem records compared to the events that are to be detected. Using spectral analysis, we can show that all models underestimate decadal and longer variability compared to speleothems (albeit to varying extents). We found that no model excels in all analyzed comparisons, although some perform better than the others in either mean or variability. Therefore, we advise a multi-model approach whenever comparing proxy data to modeled data. Considering karst and cave internal processes, e.g., through isotope-enabled karst models, may alter the variability in speleothem isotopes and play an important role in determining the most appropriate model. By exploring new ways of analyzing the relationship between the oxygen and carbon isotopes, their variability, and co-variability across timescales, we provide methods that may serve as a baseline for future studies with different models using, e.g., different isotopes, different climate archives, or different time periods.
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Miljević, Nada, and Dušan Golobočanin. "Potential Use of Environmental Isotopes in Pollutant Migration Studies." Archives of Industrial Hygiene and Toxicology 58, no. 2 (June 1, 2007): 251–62. http://dx.doi.org/10.2478/v10004-007-0015-5.

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Potential Use of Environmental Isotopes in Pollutant Migration StudiesThis article presents the use of natural abundance stable isotope (hydrogen, carbon, nitrogen, oxygen, chlorine) analysis data as a tool for providing important information about the origin of contaminants, the contribution of different sources to a multi-source plume, characterisation of their complex transport (rate and mechanisms) and for evaluating the success of contaminated site remediation. Isotopic signatures of contaminants are useful tracers of their sources, while isotopic fractionation can be used to quantitatively assess the progress of an environmental process such as biodegradation. This new isotopic approach is reliable and can offer more information than traditional techniques in pollutant migration studies, particularly after waste disposal. During biological degradation of any organic compound, molecules containing lighter isotopes are degraded, and the portion of heavier isotopes in the substrate is increased, identifying specific microbial roles in biogeochemical cycling. Since isotopic fractionation is proportional to degradation, depending on the type of contamination, a microbial degradation of 50% to 99% of the initial concentration can be quantified using isotope ratio measurements.
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Aravena, Ramon, S. L. Schiff, S. E. Trumbore, P. J. Dillon, and Richard Elgood. "Evaluating Dissolved Inorganic Carbon Cycling in a Forested Lake Watershed Using Carbon Isotopes." Radiocarbon 34, no. 3 (1992): 636–45. http://dx.doi.org/10.1017/s003382220006392x.

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Dissolved inorganic carbon (DIC) is the main acid buffer in forested lake watersheds in Canada. We used carbon isotopes (13C, 14C) to evaluate the production and cycling of DIC in an acid-sensitive lake watershed of the Precambrian Shield. Soil CO2, groundwater and stream DIC were characterized chemically and isotopically. Soil CO2 concentration profiles reflect both changes in production and in losses due to diffusion. δ13C soil CO2 profiles (δ13C values of −23‰ in summer, slightly enriched during the fall and −25%‰ during the winter) are a reflection of the isotopic composition of the sources and changes in isotopic fractionation due to diffusion. Carbon isotopic composition (13C, 14C) of the groundwater and stream DIC clearly indicate that weathering of silicates by soil CO2 is the main source of DIC in these watersheds. 14C data show that, in addition to recent groundwater, an older groundwater component with depleted 14C activity is also present in the bedrock. The carbon isotope pattern in the groundwater also implies that, besides the main springtime recharge events, contributions to the groundwater may also occur during late winter/early spring.
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Swart, Peter K., and Jim J. Leder. "The utility of stable isotopic signatures in coral skeletons." Paleontological Society Papers 1 (October 1996): 249–91. http://dx.doi.org/10.1017/s1089332600000127.

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There is a fundamental ecologic differentiation between zooxanthellate and non-zooxanthellate corals. This paper reviews factors which govern the stable carbon and oxygen isotopic composition of these groups of corals. Although the stable carbon and oxygen isotope compositions of coral skeletons are strongly influenced by environmental and physiological factors, the precise mechanisms remain a matter of debate. In particular the oxygen isotopic composition is known to be governed by the temperature and the oxygen isotopic composition of the water and perhaps also by kinetic factors. In contrast the carbon isotopic composition is controlled by a combination of photosynthesis, respiration, autotrophy, heterotrophy, and the isotopic composition of dissolved inorganic carbon. Using a combination of carbon and oxygen isotopes it is possible to distinguish zooxanthellate from non-zooxanthellate corals.
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Dissertations / Theses on the topic "Isotopes of carbon"

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Móri, Cleusa [UNESP]. "Rastreabilidade de farinhas de origem animal em tecidos de codornas de corte pela técnica dos isótopos estáveis de carbono ('intpot.13C'/'intpot.12C') e nitrogênio ('intpot.15N'/'intpot.14N')." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/104988.

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Made available in DSpace on 2014-06-11T19:33:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-05Bitstream added on 2014-06-13T18:45:25Z : No. of bitstreams: 1 mori_c_dr_botfmvz.pdf: 326000 bytes, checksum: 0ec30e51a3d43636409c064480add1c6 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
Estudos para detecção de subprodutos de origem animal em carne de aves são escassos e, em se tratando de codornas são inexistentes. O trabalho teve por objetivo a detecção de farinha de vísceras de aves (FVA) em dietas de codornas de corte no músculo peitoral quilha e tíbia pela técnica dos isótopos estáveis de carbono (13C/12C) e nitrogênio (15N/14N). Foram utilizadas 64 codornas de corte macho de um dia de idade advindas de granja comercial. As aves foram divididas em sete grupos distintos distribuídos aleatoriamente em relação às dietas experimentais que continham diferentes percentagens de FVA: 0; 1,5; 3,0; 4,5; 6,0; 7,5 e 15. As dietas foram formuladas de forma a serem isoenergéticas, isoprotéicas e isoaminoacídicas. Quatro aves de cada tratamento foram abatidas aos 42 dias de idade para colheita do músculo peitoral (Pectoralis major), quilha e tíbia para posteriormente serem analisadas. Observou-se enriquecimento isotópico de d13C e d15N nos três tecidos analisados. Em codornas de corte com 42 dias de idade, o nível de inclusão de farinha de vísceras de aves detectado compreende o intervalo de 3,0 a 4,5%.
Detection of animal origin by-products studies in poultry meat are rare and inexistent when related to quail meat. This paper aims the detection of increasing levels of poultry visceral meal (FVA) in quail meat, using carbon (13C/12C) and nitrogen (15N/14N) stable isotopes technique. Sixty four male quails aging one day originally from a commercial producer were divided in seven different groups in a random distribution. Those groups received different experimental diets containing 0; 1,5; 3,0; 4,5; 6,0; 7,5 e 15% of FVA. Those diets were formulated to be isoenergetic, isoproteic and to have the same level of amino-acids. Four individuals per treatment were sacrificed at the 42nd day for breast muscle (Pectoralis major), keel and tibia collection to later analysis. Isotopic enrichment of d13C and d15N were observed in all analyzed tissues. In 42 day old quail were detect a 3,0 and 4,5% poultry visceral meal inclusion in its diet.
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Móri, Cleusa 1974. "Rastreabilidade de farinhas de origem animal em tecidos de codornas de corte pela técnica dos isótopos estáveis de carbono ('intpot.13C'/'intpot.12C') e nitrogênio ('intpot.15N'/'intpot.14N') /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/104988.

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Orientador: Edivaldo Antônio Garcia
Banca: Ricardo de Albuquerque
Banca: Carla Cachoni Pizzolante
Banca: Carlos Ducatti
Banca: Ariel Antonio Mendes
Resumo: Estudos para detecção de subprodutos de origem animal em carne de aves são escassos e, em se tratando de codornas são inexistentes. O trabalho teve por objetivo a detecção de farinha de vísceras de aves (FVA) em dietas de codornas de corte no músculo peitoral quilha e tíbia pela técnica dos isótopos estáveis de carbono (13C/12C) e nitrogênio (15N/14N). Foram utilizadas 64 codornas de corte macho de um dia de idade advindas de granja comercial. As aves foram divididas em sete grupos distintos distribuídos aleatoriamente em relação às dietas experimentais que continham diferentes percentagens de FVA: 0; 1,5; 3,0; 4,5; 6,0; 7,5 e 15. As dietas foram formuladas de forma a serem isoenergéticas, isoprotéicas e isoaminoacídicas. Quatro aves de cada tratamento foram abatidas aos 42 dias de idade para colheita do músculo peitoral (Pectoralis major), quilha e tíbia para posteriormente serem analisadas. Observou-se enriquecimento isotópico de d13C e d15N nos três tecidos analisados. Em codornas de corte com 42 dias de idade, o nível de inclusão de farinha de vísceras de aves detectado compreende o intervalo de 3,0 a 4,5%.
Abstract: Detection of animal origin by-products studies in poultry meat are rare and inexistent when related to quail meat. This paper aims the detection of increasing levels of poultry visceral meal (FVA) in quail meat, using carbon (13C/12C) and nitrogen (15N/14N) stable isotopes technique. Sixty four male quails aging one day originally from a commercial producer were divided in seven different groups in a random distribution. Those groups received different experimental diets containing 0; 1,5; 3,0; 4,5; 6,0; 7,5 e 15% of FVA. Those diets were formulated to be isoenergetic, isoproteic and to have the same level of amino-acids. Four individuals per treatment were sacrificed at the 42nd day for breast muscle (Pectoralis major), keel and tibia collection to later analysis. Isotopic enrichment of d13C and d15N were observed in all analyzed tissues. In 42 day old quail were detect a 3,0 and 4,5% poultry visceral meal inclusion in its diet.
Doutor
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Bordinhon, André Moreira [UNESP]. "Autobalanceamento da energia e da proteína da dieta pela tilápia do Nilo por meio de isótopos estáveis de carbono e do consumo de matéria seca." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/104115.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
O objetivo deste trabalho foi avaliar a capacidade da tilápia do Nilo em 5 balancear sua dieta, quando fornecidas duas misturas de ingredientes, utilizando os 6 isótopos estáveis de carbono. Foram utilizados 225 juvenis de tilápia (peso: 5,0 ± 0,5 g), 7 distribuídos em cinco tanques. Os indivíduos alocados em um dos tanques eram 8 alimentados com uma mistura de alta proteína (MAP; δ13C = -22,62‰), os alocados em 9 um segundo tanque eram alimentados com uma mistura de baixa proteína (MBP; δ13C = 10 -14,34‰) e os animais dos outros tanques tinham acesso livre a ambas, quatro vezes ao 11 dia. Foram realizadas coletas de músculo, fígado e sangue a cada cinco dias por 86 dias, 12 exceto para o grupo alimentado com MBP (alimentado por 120 dias). As amostras 13 foram analisadas em espectrômetro de massa e as proporções consumidas das misturas 14 foram estimadas a partir do enriquecimento isotópico do carbono (δ13C). O 15 balanceamento realizado indicou redução no consumo relativo de proteína. Contudo, 16 esta relação não apresentou padrão definido em relação ao peso dos indivíduos, ou seja: 17 o balanceamento de proteína e energia para tilápia do Nilo está relacionado 18 principalmente à idade dos animais e não é claro se este processo está relacionado 19 também ao seu peso. As estimativas de consumo de um grupo animais desta espécie por 20 meio dos isótopos estáveis de carbono são semelhantes aos obtidos por outras técnicas, 21 portanto este método permite observação da diversidade deste comportamento no 22 autobalanceamento entre os indivíduos que compõe tal grupo.
This study aimed to assess the Nile tilapia ability to balance its own diet, 6 when two ingredient mixes were offered, using carbon stable isotopes. In order to 7 accomplish that, 225 Nile tilapia juveniles (average initial weight 5.0g ± 0.5g) were 8 distributed in five tanks, each containing a group of 45 fish. One group of fish were fed 9 exclusively a high protein mix (HPM; δ13C = -22.62‰), a second one fed only a low 10 protein mix (LPM; δ13C = -14.34‰). The other groups had free access to both mixes 11 (free choice system). The fish from all tanks were fed four times a day. Muscle, liver 12 and blood samples were collected at each five days (from 2 fish/tank/collection) for 86 13 days, except for the fish fed with MBP (fed for a 120 days period). The samples were 14 analyzed in a mass spectrometer and proportions of the mixes consumed were estimated 15 through its carbon isotope enrichment (δ13C). The fish diminished their protein intake 16 along the time. However, consumption did not present a clear pattern in relation to the 17 individual weight, i.e.: protein consumption patterns are mainly related to the age of the 18 individuals and it is not clear if it is also correlated to their weight. The consumption 19 estimative through stable isotopes of carbon did not conflict other studies reported in the 20 literature. Additionally this technique allowed observation of consumption among the 21 individuals from an experimental group 22.
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Bordinhon, André Moreira 1978. "Autobalanceamento da energia e da proteína da dieta pela tilápia do Nilo por meio de isótopos estáveis de carbono e do consumo de matéria seca /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/104115.

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Orientador: Luiz Edivaldo Pezzato
Banca: Wilson Massamitu Furuya
Banca: José Fernando Machado Menten
Banca: Carlos Ducatti
Banca: José Roberto Sartori
Resumo: O objetivo deste trabalho foi avaliar a capacidade da tilápia do Nilo em 5 balancear sua dieta, quando fornecidas duas misturas de ingredientes, utilizando os 6 isótopos estáveis de carbono. Foram utilizados 225 juvenis de tilápia (peso: 5,0 ± 0,5 g), 7 distribuídos em cinco tanques. Os indivíduos alocados em um dos tanques eram 8 alimentados com uma mistura de alta proteína (MAP; δ13C = -22,62‰), os alocados em 9 um segundo tanque eram alimentados com uma mistura de baixa proteína (MBP; δ13C = 10 -14,34‰) e os animais dos outros tanques tinham acesso livre a ambas, quatro vezes ao 11 dia. Foram realizadas coletas de músculo, fígado e sangue a cada cinco dias por 86 dias, 12 exceto para o grupo alimentado com MBP (alimentado por 120 dias). As amostras 13 foram analisadas em espectrômetro de massa e as proporções consumidas das misturas 14 foram estimadas a partir do enriquecimento isotópico do carbono (δ13C). O 15 balanceamento realizado indicou redução no consumo relativo de proteína. Contudo, 16 esta relação não apresentou padrão definido em relação ao peso dos indivíduos, ou seja: 17 o balanceamento de proteína e energia para tilápia do Nilo está relacionado 18 principalmente à idade dos animais e não é claro se este processo está relacionado 19 também ao seu peso. As estimativas de consumo de um grupo animais desta espécie por 20 meio dos isótopos estáveis de carbono são semelhantes aos obtidos por outras técnicas, 21 portanto este método permite observação da diversidade deste comportamento no 22 autobalanceamento entre os indivíduos que compõe tal grupo.
Abstract: This study aimed to assess the Nile tilapia ability to balance its own diet, 6 when two ingredient mixes were offered, using carbon stable isotopes. In order to 7 accomplish that, 225 Nile tilapia juveniles (average initial weight 5.0g ± 0.5g) were 8 distributed in five tanks, each containing a group of 45 fish. One group of fish were fed 9 exclusively a high protein mix (HPM; δ13C = -22.62‰), a second one fed only a low 10 protein mix (LPM; δ13C = -14.34‰). The other groups had free access to both mixes 11 (free choice system). The fish from all tanks were fed four times a day. Muscle, liver 12 and blood samples were collected at each five days (from 2 fish/tank/collection) for 86 13 days, except for the fish fed with MBP (fed for a 120 days period). The samples were 14 analyzed in a mass spectrometer and proportions of the mixes consumed were estimated 15 through its carbon isotope enrichment (δ13C). The fish diminished their protein intake 16 along the time. However, consumption did not present a clear pattern in relation to the 17 individual weight, i.e.: protein consumption patterns are mainly related to the age of the 18 individuals and it is not clear if it is also correlated to their weight. The consumption 19 estimative through stable isotopes of carbon did not conflict other studies reported in the 20 literature. Additionally this technique allowed observation of consumption among the 21 individuals from an experimental group 22.
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Linebaugh, Donald W. "Carbon cycling in the York River Estuary: an isotopic and mass balance approach using natural Carbon-14 and Carbon-18 isotopes." W&M ScholarWorks, 1999. https://scholarworks.wm.edu/etd/1539791832.

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Österlin, Carl. "STABLE CARBON ISOTOPES IN SPELEOTHEMS FROM TEMPERATE AREAS." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-55353.

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Speleothems are considered a reliable proxy for paleoclimatic reconstructions and analysis of stable carbon isotopes in speleothems is used for paleoclimatic reconstructions. However, in temperate areas that lacks C4 vegetation there are uncertainties in how to interpret changes in the δ13C signal. The aim of this study is toincrease the understanding of how the δ13C signal in speleothems from temperateareas can be interpreted. The study was divided in two parts, first a literature studythat focused on interpretations of the δ13C signal in speleothems from temperate areasand a case study in which a comparison of seven 13C records from similarenvironments in the Scandes Mountains and the Alps are made. The results from the literature study were used in the case study to draw conclusions on tree line and vegetation changes during Holocene in central northern Scandinavia. The study showed that trends in interpretation of the δ13C signal in speleothems from temperateareas are that low δ13C values are interpreted as wetter, warmer conditions with higherbio productivity, and high δ13C values are interpreted as colder, drier conditions withlower bio productivity. Further it was found in the study that vegetation changes seen in Holocene pollen data are also seen in δ13C records from Scandinavia. The δ13Csignal in temperate speleothems therefore appears to be related to changes invegetation density and to tree-line changes.
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Curtis-Summers, Shirley. "Stable Isotopes of Carbon and Nitrogen and Diet." Society of Antiquaries of Scotland, 2016. http://hdl.handle.net/10454/17856.

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Sadurski, Stephen Edward. "The Biogeochemistry of Carbon Isotopes in Local Lakes." Wright State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=wright1357745315.

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Schlanser, Kristen M. "Advancing Leaf Carbon Isotopes as a Paleo Proxy." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin159584747503534.

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McNichol, Ann P. "A study of remineralization of organic carbon in nearshore sediments using carbon isotopes /." Woods Hole, Mass. : Woods Hole Oceanographic Institution, 1986. http://hdl.handle.net/1912/3228.

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Books on the topic "Isotopes of carbon"

1

1938-, Coleman David C., and Fry Brian, eds. Carbon isotope techniques. San Diego: Academic Press, 1991.

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Isoscapes: Understanding movement, pattern, and process on earth through isotope mapping. Dordrecht: Springer, 2010.

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McNichol, Ann P. A study of remineralization of organic carbon in nearshore sediments using carbon isotopes. Woods Hole, Mass: Woods Hole Oceanographic Institution, 1986.

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Pihlaja, Kalevi. Carbon-13 NMR chemical shifts in structural and stereochemical analysis. New York: VCH, 1994.

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Introduction to isotope hydrology: Stable and radioactive isotopes of hydrogen, oxygen and carbon. London: Taylor & Francis, 2006.

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Kenkyūkai, Kyōto Daigaku Genshiro Jikkenjo Senmon. "Tanso 14 no kankyōchū ikō kyodō hyōka" Kyōto Daigaku Genshiro Jikkenjo Senmon Kenkyūkai hōkokusho. Ōsaka-fu Sennan-gun Kumatori-chō: Kyōto Daigaku Genshiro Jikkenjo, 2010.

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Tian ran qi tan qing tong wei su fen liu dong li xue ji qi ying yong. Beijing: Shi you gong ye chu ban she, 2010.

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Levy, George C. Carbon-13 nuclear magnetic resonance spectroscopy. 2nd ed. Malabar, Fla: Krieger, 1993.

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Levy, George C. Carbon-13 nuclear magnetic resonance spectroscopy. Malabar, Fla: Krieger Pub. Co., 1992.

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Breitmaier, E. Carbon-13 NMR spectroscopy: High-resolution methods and applications in organic chemistry and biochemistry. 3rd ed. New York: VCH Publishers, 1987.

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Book chapters on the topic "Isotopes of carbon"

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Wagner, Thomas, Clayton R. Magill, and Jens O. Herrle. "Carbon Isotopes." In Encyclopedia of Earth Sciences Series, 1–11. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-39193-9_176-1.

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Wagner, Thomas, Clayton R. Magill, and Jens O. Herrle. "Carbon Isotopes." In Encyclopedia of Earth Sciences Series, 194–204. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-39312-4_176.

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Wagner, Thomas, and Jens O. Herrle. "Carbon Isotopes." In Encyclopedia of Marine Geosciences, 73–78. Dordrecht: Springer Netherlands, 2016. http://dx.doi.org/10.1007/978-94-007-6238-1_44.

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Reitner, Joachim, and Volker Thiel. "Carbon Isotopes." In Encyclopedia of Geobiology, 238. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-1-4020-9212-1_123.

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Andreu-Hayles, Laia, Mathieu Lévesque, Rossella Guerrieri, Rolf T. W. Siegwolf, and Christian Körner. "Limits and Strengths of Tree-Ring Stable Isotopes." In Stable Isotopes in Tree Rings, 399–428. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92698-4_14.

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AbstractThis chapter aims at summarizing strengths and caveats on the suitability of stable carbon and oxygen isotopes in tree rings as recorders for fingerprints of environmental influences. First, environmental constraints limiting tree growth and shaping tree species distribution worldwide are discussed. Second, examples are presented for environmental conditions under which tree-ring isotopes record environmental signals particularly well, but also cases where physiological processes can mask climate signals. Third, the link between leaf-level carbon assimilation and the investment of assimilates in the stem during the annual ring formation are discussed in light of the resulting deviations of the isotopic values between leaves and tree rings. Finally, difficulties and pitfalls in the interpretation of stable isotope signals in tree rings are reviewed. These problems often result from a poor understanding of when and how the tree canopy, stems and roots are physiologically interconnected. Current literature suggests that photosynthesis and radial growth are only loosely coupled, if at all, challenging the interpretation of environmental signals recorded in tree-ring isotopes. Harsh environmental conditions (e.g. low temperatures, drought) often result in a decoupling of carbon assimilation and growth. The chapter closes by providing possible solutions on how to improve the detection of environmental information from stable isotope signals by integrating scales and different methodological approaches.
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Wei, Liang, John D. Marshall, and J. Renée Brooks. "Process-Based Ecophysiological Models of Tree-Ring Stable Isotopes." In Stable Isotopes in Tree Rings, 737–56. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92698-4_26.

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AbstractTree-ring stable isotopes can be used to parameterizeprocess-based models by providing long-term data on tree physiological processes on annual or finer time steps. They can also be used to test process-based ecophysiological models for the assumptions, hypotheses, and simplifications embedded within them. However, numerous physiological and biophysical processes influence the stable carbon (δ13C) and oxygen (δ18O) isotopes in tree rings, so the models must simplify how they represent some of these processes to be useful. Which simplifications are appropriate depends on the application to which the model is applied. Fortunately, water and carbon fluxes represented in process-based models often have strong isotopic effects that are recorded in tree-ring signals. In this chapter, we review the status of several tree-ring δ13C and δ18O models simulating processes for trees, stands, catchments, and ecosystems. This review is intended to highlight the structural differences among models with varied objectives and to provide examples of the valuable insights that can come from combining process modeling with tree-ring stable isotope data. We urge that simple stable isotope algorithms be added to any forest model with a process representation of photosynthesis and transpiration as a strict test of model structure and an effective means to constrain the models.
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Kagawa, Akira, and Giovanna Battipaglia. "Post-photosynthetic Carbon, Oxygen and Hydrogen Isotope Signal Transfer to Tree Rings—How Timing of Cell Formations and Turnover of Stored Carbohydrates Affect Intra-annual Isotope Variations." In Stable Isotopes in Tree Rings, 429–62. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92698-4_15.

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AbstractIn this chapter, we discuss post-photosynthetic processes that affect intra-annual variation in the stable isotopes of tree rings, such as timing of cell formations and turnover of stored carbohydrates, by combining research findings gained by using either natural-abundance or artificially-enriched carbon, oxygenand hydrogen isotopes. We focus on within-ring variation in stable isotope ratios, with an emphasis on aligning observed ratios in whole wood or extracted cellulose to seasonal dynamics in climate and phenology. We also present a discussion of isotopic fractionation that operates within the scope of observed variations across individual rings. We then introduce a model that traces the seasonal partitioning of photosynthate into tree rings via storage pool, which is based on experimental data gained from labeling studies using artificially enriched 13CO2 gas. Finally, we will describe our current understanding of post-photosynthetic signal transfer processes of oxygenand hydrogen isotopes from leaves to tree rings, such as exchange of oxygen and hydrogen between storage carbohydrates and local cambial water, and possible causes of difference in oxygen and hydrogen isotope fractionations. Finally, we discuss mechanisms behind how oxygen and hydrogen from foliar-absorbed liquid water is then incorporated into wood biomass, by introducing results gained from recent H218O and HDO pulse-labeling experiments.
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Kagawa, Akira, and Giovanna Battipaglia. "Post-photosynthetic Carbon, Oxygen and Hydrogen Isotope Signal Transfer to Tree Rings—How Timing of Cell Formations and Turnover of Stored Carbohydrates Affect Intra-annual Isotope Variations." In Stable Isotopes in Tree Rings, 429–62. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92698-4_15.

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AbstractIn this chapter, we discuss post-photosynthetic processes that affect intra-annual variation in the stable isotopes of tree rings, such as timing of cell formations and turnover of stored carbohydrates, by combining research findings gained by using either natural-abundance or artificially-enriched carbon, oxygenand hydrogen isotopes. We focus on within-ring variation in stable isotope ratios, with an emphasis on aligning observed ratios in whole wood or extracted cellulose to seasonal dynamics in climate and phenology. We also present a discussion of isotopic fractionation that operates within the scope of observed variations across individual rings. We then introduce a model that traces the seasonal partitioning of photosynthate into tree rings via storage pool, which is based on experimental data gained from labeling studies using artificially enriched 13CO2 gas. Finally, we will describe our current understanding of post-photosynthetic signal transfer processes of oxygenand hydrogen isotopes from leaves to tree rings, such as exchange of oxygen and hydrogen between storage carbohydrates and local cambial water, and possible causes of difference in oxygen and hydrogen isotope fractionations. Finally, we discuss mechanisms behind how oxygen and hydrogen from foliar-absorbed liquid water is then incorporated into wood biomass, by introducing results gained from recent H218O and HDO pulse-labeling experiments.
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Bowen, Robert. "Carbon-14 Dating." In Isotopes in the Earth Sciences, 247–63. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-009-2611-0_6.

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Belmecheri, Soumaya, William E. Wright, and Paul Szejner. "Sample Collection and Preparation for Annual and Intra-annual Tree-Ring Isotope Chronologies." In Stable Isotopes in Tree Rings, 103–34. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92698-4_4.

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AbstractThis chapter provides guidance for conducting studies based on stable isotope measurements in tree rings to infer past and present climate variability and ecophysiology. Balancing theoretical perspectives of stable isotope variations recorded in tree rings, intended research applications (paleoclimate or ecophysiology) and resource limitations, this chapter describes key aspects of field sampling strategies and laboratory sample processing. It presents an overview of factors influencing variations and thus interpretations of carbon and oxygen isotopes, including juvenile/age effects, canopy status and stand characteristicsto inform sampling strategies that optimize a robust paleoenvironmental and physiological signal with statistically defined confidence limits. Fieldwork considerations include the selection of a study site and trees, field equipment, and sample requirements to recover sufficient material for isotopic measurements, and the desired environmental signal. Aspects of laboratory sample processing include choosing a sampling resolution (e.g. whole ring, earlywood/latewood, thin section, etc.), sample pooling within and between trees, and particle size requirements for chemical extraction and analytical repeatability. Finally, this chapter provides a case study highlighting the potential benefits and limitations of high-resolution sub-seasonal sampling.
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Conference papers on the topic "Isotopes of carbon"

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Popov, Evgeny, Anton Polishchuk, Konstantin Grigorenko, Ian Chubchenko, and Vladimir Vitkin. "Raman detector of carbon isotopes." In Optical Sensing and Detection VI, edited by Francis Berghmans and Anna G. Mignani. SPIE, 2020. http://dx.doi.org/10.1117/12.2556262.

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SUZUKI, TOSHIO, HIROYUKI SAGAWA, and KOUICHI HAGINO. "EXOTIC STRUCTURE OF CARBON ISOTOPES." In Proceedings of the International Symposium. WORLD SCIENTIFIC, 2003. http://dx.doi.org/10.1142/9789812703972_0028.

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Almubarak, Zainab, Mohammad Alrowaie, Feng Lu, and Ranya Algeer. "Gas Chemical and Carbon Isotope Composition as a Diagnostic Tool for Energy." In SPE Annual Technical Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/209992-ms.

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Abstract As the world is moving toward a low-carbon energy structure, natural gas has become critical in the supply of global energy. The genetic identification of different types of natural gas is important for the assessment of their source and exploration potential. Chemical and carbon isotopic compositions of produced gas are useful tools to assess their origin, thermal maturity, migration and to monitor gas production. In this study, we present different geochemical approaches to assess the origin of the gases and thermal maturity as well as to evaluate the effect of adsorption on shale gas during production. Thirteen gas samples from different conventional reservoirs were analyzed for their isotopic compositions to assess gas origin and thermal maturity. To assess gas production, seven gas samples were collected periodically from the same unconventional shale interval and were analyzed for their isotopic signatures. The results demonstrate that carbon isotopic composition of methane to pentane can be used as fingerprinting tool to identify different sources of gas. The studied gases are all of a thermogenic origin and were generated from Type-II marine source rocks. Mixing of gases generated from different source rocks were observed. The mixed gases are characterized by similar isotopic profiles in methane and ethane and they differ in C3+ hydrocarbons. Thermal maturity trends were identified on the studied samples using the relationship between methane, ethane, and propane isotopes versus the wetness index (total HC/methane concentration). To study the effect of gas adsorption during production, samples produced from the same hydrocarbon source rock were assessed at different time intervals (one-year period of production). The results show small variations between isotope compositions; thus, the impact of adsorption is still uncertain and a longer-term monitoring plan is designed. The results of this study shed insight into using isotope geochemistry as an important diagnostic tool for natural gas exploration and production.
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Pyrayev, A. N., and A. A. Maksimova. "ISOTOPIC COMPOSITION OF GROUNDWATER IN OIL AND GAS DEPOSITS IN THE CENTRAL PART OF THE TRANS-URAL MEGAMONOCLISE." In All-Russian Youth Scientific Conference with the Participation of Foreign Scientists Trofimuk Readings - 2021. Novosibirsk State University, 2021. http://dx.doi.org/10.25205/978-5-4437-1251-2-117-120.

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The article presents the first results of complex isotope-hydrogeochemical studies of reservoir waters of the Upper Jurassic deposits of the central regions of the Zaural megamonoclysis. It was shown that most waters have a narrow distribution of oxygen and hy-drogen isotopes (δD from 103,2 to –85,6 % and δ18O from –15,4 to –12,9 %). Some of them have pronounced excursions on the isotopic composition, which indicates a difference in their genesis: from condensate to mixed with ancient infiltrogenic. The isotopic composition of car-bon of water-dissolved carbon dioxide (δ13СDIC from –41,6 to –16,3 %) indicates its biogenic origin and the possibility of interstratal flows from overlying horizons.
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SAGAWA, H., X. R. ZHOU, X. Z. ZHANG, and TOSHIO SUZUKI. "NEW STRUCTURE PROBLEMS IN CARBON ISOTOPES." In Proceedings of the International Symposium. WORLD SCIENTIFIC, 2004. http://dx.doi.org/10.1142/9789812702401_0033.

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Hoogakker, Babette, Caroline Anderson, Helen Grant, Claire Mahaffey, Sabena Blackbird, Erin McClymont, Rosalind Rickaby, Alex Poulton, and Victoria Peck. "Organic carbon isotopes of planktic foraminifera." In Goldschmidt2021. France: European Association of Geochemistry, 2021. http://dx.doi.org/10.7185/gold2021.7047.

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Wang, Ruixue, Alexander Piotrowski, Josephine Clegg, and Gideon Henderson. "Behaviors of Neodymium Isotopes and Carbon Isotopes in the South Atlantic Ocean." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.2756.

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Baranov, Vladimir Y., A. P. Dyad'kin, D. D. Maluta, V. A. Kuzmenko, S. V. Pigulskiy, Vladimir S. Mezhevov, Vladilen S. Letokhov, et al. "Production of carbon isotopes by laser separation." In Progress in Research and Development of High-Power Industrial CO2 Lasers, edited by Vladislav Y. Panchenko and Vladimir S. Golubev. SPIE, 2000. http://dx.doi.org/10.1117/12.394137.

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Lu, Feng Hu. "Using Isotope Technology to Identify Oil and Gas Reservoir Sweet Spots." In SPE Reservoir Characterisation and Simulation Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/212642-ms.

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Abstract Porosity and permeability of rocks are crucial parameters utilized to assess the quality of oil and gas reservoirs. Diagenesis in carbonate reservoirs commonly results in dissolution, and creates secondary porosity and permeability. At the same time, geochemical records (e.g., isotopes and elements) in the carbonate rocks are diagenetically altered. This study is to utilize the isotope technology to evaluate diagenesis and its impact on oil and gas reservoirs. Micro-samples were collected from marine carbonate rocks in a studied reservoir for carbon and oxygen isotope analyses, plus analyses of Sr isotopes and element concentrations. The analytical results show outstanding negative shifts of oxygen isotopes in some intervals, whereas carbon and strontium isotopes have a minor or little change. These intervals also contain lower element contents including strontium. It is believed that these intervals experienced diagenetic dissolution with abundant secondary porosity, and are the best potential for oil and gas reservoirs. Petrographic study indicates minor cements but higher porosity developed within these intervals. This is confirmed by high porosity measured within these intervals by using other methods including gas injection and well logging. Furthermore, the degrees of water-rock interaction were quantitively assessed by modeling covariations of isotope pairs, which can help evaluate the quality of reservoirs relating to the intensity of diagenesis. Intensive diagenesis with a high water-rock ratio particularly in a closed system may result in additional cementation, alteration of most geochemical parameters, and also reduce porosity and permeability. Thus, the isotope technology can be utilized as an effective method to assess reservoir potential and determine reservoir sweet spots. Note that carbonate cementation and recrystallization commonly occur during diagenesis, and commonly show negative oxygen isotope values. If sampling happens to contain a certain amount of cements and recrystallized carbonate minerals, the analytical results will show lower oxygen isotopes and trace elements than their primary values in the studied marine carbonates. Petrographic study was conducted to help micro-sampling, and verify that cements were not collected in the studied carbonate rocks for isotope analysis. The implementation of this study is that the isotope results obtained from one studied well can be applied in the whole field or/and the region, as diagenesis rarely occurs only around one well. This will save cost for repeatedly measurements from different wells and fields by using other methods.
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Atekwana, Eliot, Krystal Heibel, Christopher Laviolette, Georgina Lukoczki, Charles Missi, and Aaron Prock. "RESEARCH IN INTRODUCTORY STABLE ISOTOPES: DETERMINING THE SOURCE OF CARBON DIOXIDE AND ORGANIC CARBON IN SELECT CARBONATED BEVERAGES USING STABLE CARBON ISOTOPES." In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-287493.

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Reports on the topic "Isotopes of carbon"

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Heath, Jeff. Using Stable Isotopes of Carbon to Monitor Biodegradation of Pollutant Compounds,. Fort Belvoir, VA: Defense Technical Information Center, April 1995. http://dx.doi.org/10.21236/ada302216.

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Jahren, A. Hope, and Brian A. Schubert. Final Report: Fundamental Research on the Fractionation of Carbon Isotopes during Photosynthesis, New Interpretations of Terrestrial Organic Carbon within Geologic Substrates. Office of Scientific and Technical Information (OSTI), August 2017. http://dx.doi.org/10.2172/1373486.

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Schubert, Brian, and A. Hope Jahren. Final Technical Report: Fundamental Research on the Fractionation of Carbon Isotopes during Photosynthesis, New Interpretations of Terrestrial Organic Carbon within Geologic Substrates. Office of Scientific and Technical Information (OSTI), November 2017. http://dx.doi.org/10.2172/1410654.

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Keeling, Ralph F. Measurements and modeling of CO2 concentration and isotopes to improve process-level understanding of Arctic and boreal carbon cycling. Final Report. Office of Scientific and Technical Information (OSTI), September 2017. http://dx.doi.org/10.2172/1395576.

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Boreham, C. J., L. Wang, J. Sohn, N. Jinadasa, Z. Hong, J. Chen, E. Grosjean, and A. Jarrett. Exploring for the Future - NDI Carrara 1 gas geochemistry: molecular composition, carbon and hydrogen isotopes of hydrocarbon gases, and the sources of molecular hydrogen and helium. Geoscience Australia, 2022. http://dx.doi.org/10.11636/record.2022.014.

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O'Leary, M. H. (Carbon isotope fractionation inplants). Office of Scientific and Technical Information (OSTI), January 1990. http://dx.doi.org/10.2172/7206375.

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Peng, T. (Modeling the distribution of carbon isotopes in the ocean, CO sub 2 uptake, and CO sub 2 exchange and radon measurements, Bern, Switzerland and Heidelberg, W. Germany, June 23--August 31, 1989). Office of Scientific and Technical Information (OSTI), September 1989. http://dx.doi.org/10.2172/5651266.

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O`Leary, M. H. [Carbon isotope fractionation inplants]. Final report. Office of Scientific and Technical Information (OSTI), December 1990. http://dx.doi.org/10.2172/10153604.

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Burke, F. P., R. A. Winschel, and M. S. Lancet. Stable carbon isotope analysis of coprocessing materials. Office of Scientific and Technical Information (OSTI), June 1989. http://dx.doi.org/10.2172/5717939.

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Davisson, M. L. Isotope tracers of organic carbon during artificial recharge. Office of Scientific and Technical Information (OSTI), February 1998. http://dx.doi.org/10.2172/645065.

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