Stable Isotope Of C And N
Mostrando 1-12 de 51 artigos, teses e dissertações.
-
1. SOIL CHEMICAL CHANGES AND RESEMBLANCES IN A CHRONOSEQUENCE RAINFOREST-SUGARCANE-PASTURELAND IN THE ATLANTIC FOREST BIOME
ABSTRACT This study evaluated soil chemical and isotopic changes in soils of a chronosequence rainforest-sugarcane-pasture in the Atlantic Forest biome, Brazil. Soil samples were collected (0-20 cm) in areas of native Brazilian Atlantic rainforest, sugarcane plantation and pastures of Brachiaria decumbens. The soil analyses performed were: pH (water 1:2.5),
CERNE. Publicado em: 2020-12
-
2. Geochemical Investigation of Tar Balls Collected in a Brazilian Beach Using Biomarkers, Ni/V, δ13C Ratios and Ultra-High Resolution FT-ICR Mass Spectrometry
Representative tar balls collected in two distinct years (2012 and 2014) in a beach along the State of Bahia, northeastern Brazil, were geochemically characterized in order to identify correlations between them and investigate potential sources. Terpanes and steranes biomarkers (detected by gas chromatography coupled to mass spectrometry, GC-MS), carbon stab
J. Braz. Chem. Soc.. Publicado em: 2020-04
-
3. Vegetation and climate changes in the forest of Campinas, São Paulo State, Brazil, during the last 25,000 cal yr BP
Abstract A paleoenvironmental reconstruction was performed in a Riparian Forest near Campinas to improve knowledge of paleoclimate and paleoenvironment in the State of São Paulo, Brazil. A sediment core of 182 cm depth was collected in a swamp located within a Cerrado/Seasonal Semi-deciduous ecotone forest. The chronological frame is given by eight radiocar
Braz. J. Geol.. Publicado em: 10/10/2019
-
4. Changes in trophic characteristics of two fish species of Astyanax (Teleostei: Characidae) in response to aquatic pollution
ABSTRACT The trophic plasticity of most fish species of Astyanax Baird & Girard, 1854 in response to environmental changes and resource availability is high. This work evaluates the differences in the trophic characteristics of two congeneric species, Astyanax taeniatus (Jenyns, 1842) and Astyanax lacustris (Lütken, 1875), in Rio das Velhas Basin, which is
Zoologia (Curitiba). Publicado em: 22/07/2019
-
5. Traceability of animal protein byproducts in ruminants by multivariate analysis of isotope ratio mass spectrometry to prevent transmission of prion diseases
Abstract Background: Ruminant feed containing animal byproduct proteins (ABPs) is prohibited in many countries due to its risk of transmitting prion diseases (PD). In most cases the entire herd is sacrificed, which causes great harm to the producer countries by preventing their exportation of ruminant derived-products. Methods: We used stable isotope ratio
J. Venom. Anim. Toxins incl. Trop. Dis. Publicado em: 13/05/2019
-
6. Standardization of A Sample-Processing Methodology for Stable Isotope Studies in Poultry
ABSTRACT The objective of this study was to determine if lipid extraction processes alter the isotopic value of δ13C and δ15N of tissues (pectoral muscle, thigh and liver) and eggs and if the use of anticoagulants interferes with blood and plasma δ13C and δ15N isotopic values. Samples were acquired from the same flock of birds. The 32 egg samples were ra
Braz. J. Poult. Sci.. Publicado em: 18/04/2019
-
7. Trophic ecology of citrus pests based on stable isotope analysis
ABSTRACT: Macrodactylus pumilio Burm. (Coleoptera: Scarabeidae) and Naupactus cervinus (Boh.) (Coleoptera: Curculionidae) are considered primary pests in citrus crops in Brazil, causing damage to plants and decreasing productivity. However, few studies investigate the ecology of these insects. In this context, the use of stable isotopes analysis (SIA) emerge
Sci. agric. (Piracicaba, Braz.). Publicado em: 2018-12
-
8. The trophic niche of Mesoclemmys vanderhaegei (Testudines: Chelidae): evidence from stable isotopes
ABSTRACT Ecological niche is the multidimensional space comprising the resources used by an organism. Intraspecific variation in resource exploitation is common in reptile populations to maximize coexistence of individuals. The use of stable isotope analysis is an effective tool when there are variations in resource exploitation, since it can provide quantit
Zoologia (Curitiba). Publicado em: 23/10/2017
-
9. Stable isotope evidence for trophic overlap of sympatric Mexican Lake Chapala silversides (Teleostei: Atherinopsidae: Chirostoma spp.)
We explore the trophic role that a diverse sympatric group of fishes in the genus Chirostoma play in a large, shallow lake in central Mexico, Lake Chapala. We use δ13C and δ15N stable isotope - based food web analyses to explore how they relate to other components of the Lake Chapala ecosystem. We find five Chirostoma species in top trophic levels of the C
Neotrop. ichthyol.. Publicado em: 02/06/2015
-
10. Synthesis of 15N-enriched urea (CO(15NH2)2) from 15NH3, CO, and S in a discontinuous process
CO(15NH2)2 enriched with the stable isotope 15N was synthesized based on a reaction involving CO, 15NH3, and S in the presence of CH3OH. The method differs from the industrial method; a stainless steel reactor internally lined with polytetrafluoroethylene (PTFE) was used in a discontinuous process under low pressure and temperature. The yield of the synthesi
Braz. J. Chem. Eng.. Publicado em: 2012-12
-
11. DEPLOYMENT OF METHOD FOR ANALYSIS OF STABLE CARBON ISOTOPES (N-ALKANES C1-C5) IN GAS SAMPLES AT LOW CONCENTRATIONS / IMPLANTAÇÃO DE MÉTODO PARA ANÁLISE DE ISÓTOPOS ESTÁVEIS DE CARBONO (N-ALCANOS C1-C5) EM GASES A BAIXAS CONCENTRAÇÕES
The concentration and isotopic composition of n-alkanes C1-C5 has revealed as a powerful tool for interpretation of interesting processes in the oil exploration industry, studies of global climate change, oil biodegradation and carbon cycle elucidation. In this context, studies about methane analysis have been distinguished and multiplied due to the importan
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 06/10/2011
-
12. Síntese de uréia enriquecida com o isótopo 13C e/ou 15N / Synthesis of 13C- and/or 15N-enriched urea
No presente trabalho foi sintetizada a 13CO(15NH2)2, enriquecida em 13C e/ou 15N, a partir da reação entre 13CO, 15NH3, S e CH3OH (meio líquido), sob baixa pressão e temperatura, com simultânea produção de H2S. A reação ocorreu em reator de aço inoxidável, revestido internamente com politetrafluoretileno. Inicialmente, adicionou-se S no interior d
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/02/2011