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Determination Methods and Distribution Characteristics of Nitrogen Isotopes in Different Nitrogenous Components of Crude Oil

open access: yesYankuang ceshi, 2023
BACKGROUNDThe distribution of nitrogen isotopes has important significance in paleoclimate, paleo-sedimentary and evolutionary characteristics. Nitrogen is one of the important heteroatomic elements in crude oil.
Min LI   +5 more
doaj   +1 more source

Presenting the Compendium Isotoporum Medii Aevi, a Multi-Isotope Database for Medieval Europe

open access: yesScientific Data, 2022
Measurement(s) Isotopes Technology Type(s) Mass Spectrometry Factor Type(s) Carbon isotopes • nitrogen isotopes • sulfur isotopes • oxygen isotopes • strontium isotopes Sample Characteristic - Organism Humans • Animals • Plants Sample Characteristic ...
Carlo Cocozza   +4 more
doaj   +1 more source

Inter-Laboratory Comparison of Measuring Organic Carbon and Stable Nitrogen Isotopes in Marine Sediments by Elemental Analysis-Isotope Ratio Mass Spectrometry

open access: yesYankuang ceshi, 2020
BACKGROUND Organic carbon and nitrogen stable isotopes (δ13C, δ15N) in marine sediments are used as effective indicators to trace the changes of air, temperature, precipitation and other parameters in different geological time. Elemental analysis-isotope
CHANG Wen-bo   +3 more
doaj   +1 more source

Sedimentary pyrite sulfur isotopes track the local dynamics of the Peruvian oxygen minimum zone

open access: yesNature Communications, 2021
To explore the importance of local vs. global sulfur-cycle controls on variations in pyrite sulfur isotopes, the authors couple carbon-nitrogen-sulfur concentrations and stable isotopes of sediments from the Peruvian oxygen minimum zone, identifying a ...
Virgil Pasquier   +2 more
doaj   +1 more source

Isotopic Fingerprinting: A Promising Tool for Coffee Authenticity Checks

open access: yesProceedings, 2023
Almost every physical or chemical process in nature favors certain light stable isotopes over others, and thereby leaves an isotopic “fingerprint” on the substances involved.
Johannes Wintel   +4 more
doaj   +1 more source

A pilot study of stable isotope fractionation in Bombyx mori rearing

open access: yesScientific Reports, 2023
Hydrogen, oxygen, carbon, and nitrogen isotopes derived from three different strains of silkworms at different life stages involved in silkworm rearing, were measured to understand the fractionation characteristics of stable isotopes at different stages ...
Hao Li   +11 more
doaj   +1 more source

Effects of Upwelling Intensity on Nitrogen and Carbon Fluxes through the Planktonic Food Web off A Coruña (Galicia, NW Spain) assessed with Stable Isotopes

open access: yesDiversity, 2020
The input of new nutrients by upwelling in shelf waters, and the associated carbon and nitrogen fluxes, can be traced by their stable isotope signatures in organic matter.
Antonio Bode   +2 more
doaj   +1 more source

LIBS plasma in atmospheric pressure argon, nitrogen and helium: Spatio-temporal distribution of plume emission and Hα linewidth

open access: yesNuclear Materials and Energy, 2023
Laser Induced Breakdown Spectroscopy (LIBS) method is considered for assessing the retention of hydrogen isotopes in the ITER plasma-facing components during the maintenance breaks when the reactor is filled with near atmospheric pressure nitrogen or ...
Indrek Jõgi   +4 more
doaj   +1 more source

Sources of nitrate in a heavily nitrogen pollution bay in Beibu Gulf, as identified using stable isotopes

open access: yesFrontiers in Marine Science, 2022
Eutrophication, mainly caused by the oversupply of inorganic nitrogen and phosphate, has increased and become a serious environmental problem in the coastal bays of Beibu Gulf, a newly developing industry and port in South China.
Shangjun Cai   +13 more
doaj   +1 more source

Amino Acid δ15N Can Detect Diet Effects on Pollution Risks for Yellow-Legged Gulls Overlooked by Trophic Position

open access: yesFrontiers in Marine Science, 2021
The use of top-consumers as bioindicators of the health of food webs is hampered by uncertainties in their effective use of resources. In this study, the abundance of stable nitrogen isotopes in amino acids from homogenised eggs of the Yellow-legged Gull
Antonio Bode   +3 more
doaj   +1 more source

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