Stable Isotopic
Mostrando 1-12 de 122 artigos, teses e dissertações.
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1. 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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2. 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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3. 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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4. 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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5. 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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6. 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
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7. Use of stable isotopes of carbon to detect coconut water adulteration
ABSTRACT: Industrialized coconut water may have been adulterated by adding sugar above the limit permitted by law. According to Brazilian law, industrialized coconut water can receive the maximum addition of 1 g of sugar per 100 mL of the drink. This work aimed to detect adulteration in industrialized coconut water produced in Brazil and measure the relative
Sci. agric. (Piracicaba, Braz.). Publicado em: 2019-05
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8. 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
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9. Paleoenvironmental Characterization of a High-Mountain Environment in the Atlantic Forest in Southeastern Brazil
ABSTRACT: Records of changes in the phytosociological structure of vegetation can be observed more clearly in soils that have more significant accumulation of organic matter, like those occurring in high-mountain environments. The aim of this study was to characterize soils formed in high-mountain environments in the Itatiaia National Park (INP), state of Ri
Rev. Bras. Ciênc. Solo. Publicado em: 14/11/2018
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10. Simultaneous determination of candesartan and hydrochlorothiazide in human plasma by LC-MS/MS
Abstract A simple, sensitive, rapid and highly efficient LC-MS/MS method was developed for the determination of Candesartan and Hydrochlorothiazide simultaneously in human plasma. The method employed Zorbax eclipse C18 (150 X 4.6 mm, 5µ) column using acetate buffer: acetonitrile (25:75%, v/v) as the mobile phase. The mobile phase flow rate is 1 mL/min which
Braz. J. Pharm. Sci.. Publicado em: 07/06/2018
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11. Relationships of stable isotopes, water-rock interaction and salinization in fractured aquifers, Petrolina region, Pernambuco State, Brazil
Abstract The Petrolina County, Pernambuco State, Brazil, presents specificities that make it unique from a hydrogeological point of view. Water resource scarcity is both a quantitative and qualitative issue. The climate is classified as semiarid, having low precipitation, along with high temperatures and evapotranspiration rates. Aquifer zones are related to
REM, Int. Eng. J.. Publicado em: 2018-03
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12. Contribution of Eucalyptus Harvest Residues and Nitrogen Fertilization to Carbon Stabilization in Ultisols of Southern Bahia
ABSTRACT: Eucalyptus forests in southern Bahia (BA) are planted in soils with a sandy surface layer and humid tropical climate, conditions that lead to soil carbon (C) decomposition. Recent studies have shown that nitrogen (N) may be important for soil C stabilization. The aim of this study was to evaluate the contribution of Eucalyptus harvest residues and
Rev. Bras. Ciênc. Solo. Publicado em: 01/02/2018