Results 21 to 30 of about 65,167,055 (305)
The role of the artificial ponds for the conservation of mammals in the state of Santa Catarina
Man has profoundly modified the upper valley of the Uruguay River and its basin. The plains of these valleys and the lower areas of the hills have been modified for agricultural production, leaving small patches of wild forest on the tops of the hills ...
Mirian Carbonera +2 more
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Glacier melt provides an important source of freshwater, particularly during dry years and late in the summer, after most of the seasonal snow has melted.
Kristina Penn +3 more
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Applicability study of deuterium excess in bottled water life cycle analyses
Paper explores the possible use of d‑excess in the investigation of bottled water. Based on the data set from Brencic and Vreca’s paper (2006). Identification of sources and production processes of bottled waters by stable hydrogen and oxygen isotope ...
Mihael Brenčič, Polona Vreča
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A collection of 514 stable isotope water samples from the Atacama Desert is being reassessed geostatistically. The evaluation reveals that adjacent Andean catchments can exhibit distinct δ18O and δ2H value ranges in meteoric waters, despite similar ...
Konstantin W. Scheihing +4 more
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Isotopic characterization of all identified hydrological units in Lake Toba such as precipitation, inflows, outflows, and lake water, as a first assessment of lake water balance study, has been conducted.
P. Sidauruk +2 more
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The synthesis of dimethyl carbonate (DMC) from carbon dioxide and methanol was studied over a ceria- zirconia mixed metal oxide. When using oxygen-18 labeled ceria-zirconia, no oxygen-18 labeled DMC or water was observed.
Cécile Daniel +2 more
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Incorporation of oxygen-18 into nucleosides and bases
Extensive incorporation of oxygen-18 at position O4 of the pyrimidine nucleus results from exchange between H218O and nucleosides or bases in 1N HC1 at 100 degrees. The reaction is hindered by substitution at C-5 with the greatest effect shown in pseudouridine (R = ribosy1) and the least in uridine (R = H).
G, Puzo, K H, Schram, J A, McCloskey
openaire +3 more sources
The measurement of naturally occurring stable hydrogen (δ2H) and carbon (δ13C) isotopes in wings of the eastern North American monarch butterflies (Danaus plexippus) have proven useful to infer natal origins of individuals overwintering in Mexico.
Keith A. Hobson +3 more
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The origin and formation of the groundwater in the Mekong Delta are the complex problem, which has not one solution nowadays. So the exploitation scheme still has many limitations.
Viet Lam Hoang Quoc +2 more
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An underlying assumption when estimating total energy expenditure (TEE) using doubly labelled water (DLW) is that the injected isotopes (lsO and 2H) leave the body only in the form of CO, and H20. However, both isotopes have additional routes of loss. We
Geir Gotaas +3 more
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