Isotopic
Mostrando 1-12 de 719 artigos, teses e dissertações.
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1. Breast carcinoma metastasis and Wolf’s isotopic response
Abstract Wolf’s isotopic phenomenon occurs when a new dermatosis appears on a site that has already healed from a previous dermatological disease of another etiology. This report describes the case of a 44-year-old female patient undergoing treatment for breast carcinoma who recently had brownish erythematous lesions appearing on the scar region of previou
Anais Brasileiros de Dermatologia. Publicado em: 2022
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2. Isotopic Analysis of Sugarcane/Petroleum Polyethylene Blends: A Perspective on the Application of Stable Isotope Method (δ13C)
In the present work, we propose the application of stable isotope analysis (δ13C) as an auxiliary tool for the inspection of sugarcane/petroleum polyethylene blends. Our results are supported from the analysis of selected samples by accelerator mass spectrometry (14C-AMS). From the results, it was concluded that the δ13C method is suitable to discriminate
J. Braz. Chem. Soc.. Publicado em: 2021-01
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3. 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
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4. Structural Study of Phenolic Acids by Triple Quadrupole Mass Spectrometry with Electrospray Ionization in Negative Mode and H/D Isotopic Exchange
This work reports the theoretical and experimental study of fragmentation reactions in the gas phase of five phenolic acids using triple quadrupole mass spectrometry by electrospray ionization in negative ionic mode, as well as the isotope exchange experiments. MS/MS spectra were analyzed to suggest the fragmentation mechanisms, while theoretical calculation
J. Braz. Chem. Soc.. Publicado em: 2020-02
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5. Sugarcane inoculated with endophytic diazotrophic bacteria: effects on yield, biological nitrogen fixation and industrial characteristics
Abstract: The growing need for the use of clean energy has led society to seek alternatives to fossil fuels in order to less pollute the environment. Sugarcane has been known to produce enough biomass and to have associative microorganisms, such as plant growth-promoting bacteria (PGPB), which have the potential to improve the yield of crops. The objective
An. Acad. Bras. Ciênc.. Publicado em: 25/11/2019
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6. Natural abundance of 15N of N derived from the atmosphere by different strains of Bradyrhizobium in symbiosis with soybean plants
RESUMO: Para quantificar a FBN em leguminosas, através da técnica de abundância natural de 15N, é importante conhecer a abundância de 15N da planta leguminosa crescida inteiramente dependente da FBN (valor ‘B’). O objetivo deste estudo foi determinar a abundância natural de 15N do N2 fixado por diferentes estirpes de Bradyrhizobium em simbiose com
Cienc. Rural. Publicado em: 25/11/2019
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7. Salinity and stable oxygen isotope relationship in the Southwestern Atlantic: constraints to paleoclimate reconstructions
Abstract: Stable isotopes have been widely used in the literature both to discuss current ocean circulation processes, as well as to reconstitute paleoceanographic parameters. The distribution of oxygen and deuterium stable isotopes in seawater (δ18Osw and δDsw) at the Western Tropical South Atlantic border was investigated to better understand the main fr
An. Acad. Bras. Ciênc.. Publicado em: 30/09/2019
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8. Geochemistry, Sm-Nd isotopes and SHRIMP U-Pb geochronology of the Morro do Coco Granite (RJ, Brazil): another piece of the post-collisional magmatism of the Ribeira Belt
Abstract The Morro do Coco granite (MC) is a post-collisional intrusive body that was emplaced at Ribeira Belt, in the Cambro-Ordovician, succeeding the final stages of the Gondwana supercontinent amalgamation. This unit requires more studies, contrasting with similar best investigated occurrences of the central Ribeira Belt. This work presents a detailed in
Braz. J. Geol.. Publicado em: 12/09/2019
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9. Impactos da mudança de vegetação local no aporte de matéria orgânica para um estuário tropical preservado (Estuário do Rio Itapicuru – BA)
Estuaries are major areas of organic matter (OM) deposition, playing an important role in the global carbon cycle. The Itapicuru's river estuary (IRE) is in the North Coast of Bahia (Brazil), in na Environmental Protected Area. Although it presents preserved conditions, some environmental changes caused by human activities can be observed. This study evaluat
Quím. Nova. Publicado em: 15/08/2019
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10. 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
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11. Mercury and methylmercury in carapace of the marine turtle Caretta caretta, in northeastern Brazil and its potential for environmental monitoring
Abstract: The present work tests the use of carapace fragments of the marine turtle Caretta caretta as a tool for environmental biomonitoring of mercury (Hg) and to evaluate the influence of biological and ecological factors in Hg concentrations. Samples of carapace fragments were obtained during the nesting season of 2012 and 2016 and were analyzed for thei
An. Acad. Bras. Ciênc.. Publicado em: 10/07/2019
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12. Geochronological systematics of the Huayna Potosí, Zongo and Taquesi plutons, Cordillera Real of Bolivia, by the K/Ar, Rb/Sr and U/Pb methods
Abstract The Huayna Potosi, Zongo and Taquesi are Triassic plutons located at the core of the Real Cordillera of Bolivia. In this paper, several Rb-Sr and K-Ar ages obtained in the past at the São Paulo Geochronology Laboratory, yet unpublished, will be presented, along with newer U-Pb Sensitive High-Resolution Ion Microprobe (SHRIMP) determinations made in
Braz. J. Geol.. Publicado em: 01/07/2019