scholarly journals Thallium isotope fractionation during magma degassing: Evidence from experiments and Kamchatka arc lavas

2021 ◽  
Author(s):  
Sune G. Nielsen ◽  
Yunchao Shu ◽  
Bernard J. Wood ◽  
Jerzy Blusztajn ◽  
Maureen Auro ◽  
...  
Keyword(s):  
Isotope Fractionation ◽  
Magma Degassing

scholarly journals Thallium isotope fractionation during magma degassing: evidence from experiments and Kamchatka arc lavas

2021 ◽  
Author(s):  
Sune Nielsen ◽  
Maureen Auro ◽  
Yunchao Shu ◽  
Bernard Wood ◽  
Gerhard Wörner ◽  
...  
Keyword(s):  
Isotope Fractionation ◽  
Magma Degassing

Isotopic Characterization (2H, 13C, 37Cl, 81Br) of the Abiotic Sinks of Methyl Bromide and Methyl Chloride in Water and Implications for Future Studies.

2018 ◽  
Author(s):  
Axel Horst ◽  
Magali Bonifacie ◽  
Gérard Bardoux ◽  
Hans-Hermann Richnow
Keyword(s):  
Methyl Bromide ◽  
Isotope Fractionation ◽  
Methyl Chloride ◽  
Methyl Halides ◽  
Future Studies ◽  
Halide Exchange ◽  
Isotopic Characterization

In this study we investigated the isotope fractionation of the abiotic sink (hydrolysis, halide exchange) of methyl halides in water.<br>

Temperature and its measurement

2017 ◽  
Author(s):  
Andrew Clarke
Keyword(s):  
Thermal Equilibrium ◽  
Isotope Fractionation ◽  
Thermodynamic Temperature ◽  
The Other ◽  
Deterministic Models ◽  
Triple Point Of Water ◽  
Temperature Scales ◽  
Classical Thermodynamics ◽  
The Relationship ◽  
Unit Of Temperature

Temperature is that property of a body which determines whether it gains or loses energy in a particular environment. In classical thermodynamics temperature is defined by the relationship between energy and entropy. Temperature can be defined only for a body that is in thermodynamic and thermal equilibrium; whilst organisms do not conform to these criteria, the errors in assuming that they do are generally small. The Celsius and Fahrenheit temperature scales are arbitrary because they require two fixed points, one to define the zero and the other to set the scale. The thermodynamic (absolute) scale of temperature has a natural zero (absolute zero) and is defined by the triple point of water. Its unit of temperature is the Kelvin. The Celsius scale is convenient for much ecological and physiological work, but where temperature is included in statistical or deterministic models, only thermodynamic temperature should be used. Past temperatures can only be reconstructed with the use of proxies, the most important of which are based on isotope fractionation.

scholarly journals Unravelling the process of petroleum hydrocarbon biodegradation in different filter materials of constructed wetlands by stable isotope fractionation and labelling studies

2021 ◽  
Author(s):  
Andrea Watzinger ◽  
Melanie Hager ◽  
Thomas Reichenauer ◽  
Gerhard Soja ◽  
Paul Kinner
Keyword(s):  
Stable Isotope ◽  
Constructed Wetlands ◽  
Hydrogen Isotope ◽  
Petroleum Hydrocarbon ◽  
Isotope Fractionation ◽  
Isotope Effects ◽  
Filter Material ◽  
Hydrocarbon Biodegradation ◽  
Stable Isotope Fractionation ◽  
Filter Materials

AbstractMaintaining and supporting complete biodegradation during remediation of petroleum hydrocarbon contaminated groundwater in constructed wetlands is vital for the final destruction and removal of contaminants. We aimed to compare and gain insight into biodegradation and explore possible limitations in different filter materials (sand, sand amended with biochar, expanded clay). These filters were collected from constructed wetlands after two years of operation and batch experiments were conducted using two stable isotope techniques; (i) carbon isotope labelling of hexadecane and (ii) hydrogen isotope fractionation of decane. Both hydrocarbon compounds hexadecane and decane were biodegraded. The mineralization rate of hexadecane was higher in the sandy filter material (3.6 µg CO2 g−1 day−1) than in the expanded clay (1.0 µg CO2 g−1 day−1). The microbial community of the constructed wetland microcosms was dominated by Gram negative bacteria and fungi and was specific for the different filter materials while hexadecane was primarily anabolized by bacteria. Adsorption / desorption of petroleum hydrocarbons in expanded clay was observed, which might not hinder but delay biodegradation. Very few cases of hydrogen isotope fractionation were recorded in expanded clay and sand & biochar filters during decane biodegradation. In sand filters, decane was biodegraded more slowly and hydrogen isotope fractionation was visible. Still, the range of observed apparent kinetic hydrogen isotope effects (AKIEH = 1.072–1.500) and apparent decane biodegradation rates (k = − 0.017 to − 0.067 day−1) of the sand filter were low. To conclude, low biodegradation rates, small hydrogen isotope fractionation, zero order mineralization kinetics and lack of microbial biomass growth indicated that mass transfer controlled biodegradation.

Equilibrium Cu isotope fractionation in copper minerals: a first-principles study

2021 ◽  
Vol 564 ◽  
pp. 120060
Author(s):  
Shanqi Liu ◽  
Yongbing Li ◽  
Jie Liu ◽  
Zhiming Yang ◽  
Jianming Liu ◽  
...  
Keyword(s):  
First Principles ◽  
Isotope Fractionation ◽  
First Principles Study ◽  
Cu Isotope
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