Results 1 to 10 of about 288,749 (288)

Adsorption-induced negative carbon isotope sequence in over-mature coal-type gas from the southwest Ordos Basin [PDF]

Scientific Reports
The carbon isotope sequence of alkanes is a key indicator used to distinguish organic from inorganic gas. A negative carbon isotope sequence (i.e., δ 13C1 > δ 13C2 > δ 13C3 > δ 13C4) is a characteristic feature of inorganic gas. Some gas samples from the
Xiaoming Wu, Qiang Meng, Haiwei Zhu, Heng Zhao, Yu Xiao, Zhuo Guo, Mengting Zhang, Liyu Liu, Luxing Dou, Zhigang Wen   +9 more
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Efficient palladium-catalyzed electrocarboxylation enables late-stage carbon isotope labelling [PDF]

Nature Communications
Carbon isotope labelling of bioactive molecules is essential for accessing the pharmacokinetic and pharmacodynamic properties of new drug entities. Aryl carboxylic acids represent an important class of structural motifs ubiquitous in pharmaceutically ...
Gabriel M. F. Batista, Ruth Ebenbauer, Craig Day, Jonas Bergare, Karoline T. Neumann, Kathrin H. Hopmann, Charles S. Elmore, Alonso Rosas-Hernández, Troels Skrydstrup   +8 more
doaj   +2 more sources

Benthic alkalinity fluxes from coastal sediments of the Baltic and North seas: comparing approaches and identifying knowledge gaps [PDF]

Biogeosciences, 2022
Benthic alkalinity production is often suggested as a major driver of net carbon sequestration in continental shelf ecosystems. However, information on and direct measurements of benthic alkalinity fluxes are limited and are especially challenging when ...
B. Van Dam, N. Lehmann, N. Lehmann, N. Lehmann, M. A. Zeller, A. Neumann, D. Pröfrock, M. Lipka, H. Thomas, H. Thomas, M. E. Böttcher, M. E. Böttcher, M. E. Böttcher   +12 more
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Research Progress on Spatiotemporal Distribution Characteristics of Carbon Stable Isotopes in Wines from New and Old World Countries [PDF]

Shipin Kexue, 2023
With the continuous development of economic globalization, the production and consumption of wine in New and Old World countries have shown a steady growth trend. Wines of different grades and styles have been developed, which are related to geographical
MA Yanfei, SU Yingyue, WANG Lishan, QI Pengyu, KANG Tianhao, WANG Li, MA Haiyan, XU Guoqian, ZHANG Ang
doaj   +1 more source

Study on Specific Carbon Isotope Fractionation of n-Alkanes during Column Chromatography Separation-Molecular Sieve Complexation Adsorption

Yankuang ceshi, 2021
BACKGROUND Before analyzing the carbon isotopes of n-alkanes by gas chromatography-gas isotope mass spectrometry (GC-IRMS), it is necessary to pre-separate and enrich n-alkanes and isoparaffins in saturated hydrocarbon samples. Whether the carbon isotope
DONG Hao-wei, ZHAO Jia-yu, ZENG Fan-gang, XIE Man-man, SHANG Wen-yu, WANG Shu-xian, SUN Qing   +6 more
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Carbon isotopic evolution of hydrocarbon gases generated from carbonate source rocks via different thermal simulation methods

Shiyou shiyan dizhi, 2022
Chinese marine source rocks are generally at the stage of high- to over-mature, there are still some uncertainties about whether the existing hydrocarbon isotopic indexes can be directly employed to distinguish the genetic types of marine carbonate ...
Lei CHEN, Lunju ZHENG, Haiping HUANG, Chuanxiang NING   +3 more
doaj   +1 more source

Application of Carbon Isotope Abundance Measurement by Mass Spectrometry in the Separation of Ethanol by Gas Diffusion Method

Journal of Isotopes, 2022
Ethanol is a feasible medium for diffusion separation of carbon isotopes. In order to obtain the separation coefficient of gas diffusion separation of ethanol, the application of elemental analysis isotope ratio mass spectrometry (EA-IRMS) to measure the
WANG Fei;PAN Jianxiong;ZHOU Mingsheng;JIANG Dongjun;LI Junjie
doaj   +1 more source

The potential of stable carbon and nitrogen isotope analysis of foxtail and broomcorn millets for investigating ancient farming systems

Frontiers in Plant Science, 2022
Foxtail and broomcorn millets are the most important crops in northern China since the early Neolithic. However, little evidence is available on how people managed these two crops in the past, especially in prehistory. Previous research on major C3 crops
Yu Dong, Yu Dong, Xiaoguang Bi, Rubi Wu, Eric J. Belfield, Nicholas P. Harberd, Bent T. Christensen, Mike Charles, Amy Bogaard   +8 more
doaj   +1 more source

Compound-Specific Stable Isotope Analysis of Amino Acids in Pelagic Shark Vertebrae Reveals Baseline, Trophic, and Physiological Effects on Bulk Protein Isotope Records

Frontiers in Marine Science, 2021
Variations in stable carbon and nitrogen isotope compositions in incremental tissues of pelagic sharks can be used to infer aspects of their spatial and trophic ecology across life-histories.
Sarah Magozzi, Sarah Magozzi, Simon R. Thorrold, Leah Houghton, Victoria A. Bendall, Stuart Hetherington, Gonzalo Mucientes, Gonzalo Mucientes, Lisa J. Natanson, Nuno Queiroz, Miguel N. Santos, Miguel N. Santos, Clive N. Trueman   +12 more
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A view of the European carbon flux landscape through the lens of the ICOS atmospheric observation network [PDF]

Atmospheric Chemistry and Physics, 2023
The ICOS (Integrated Carbon Observation System) network of atmospheric measurement stations produces standardized data on greenhouse gas concentrations at 46 stations in 16 different European countries (March 2023).
I. Storm, U. Karstens, C. D'Onofrio, A. Vermeulen, A. Vermeulen, W. Peters, W. Peters   +6 more
doaj   +1 more source