Simultaneous measurement stable and radiogenic Nd isotopic compositions by MC-ICP-MS with a single-step chromatographic extraction technique

Author(s):  
Jianghao Bai ◽  
Fang Liu ◽  
Zhaofeng Zhang ◽  
Jinlong Ma ◽  
Le Zhang ◽  
...  

Removing the interferences such as Ce on Nd isotopes during column chemistry is hardly achieved due to their similar properties. In this study, we established a simple but efficient Nd...

Author(s):  
Ferrari Colin ◽  
Resongles Eléonore ◽  
Freydier Rémi ◽  
Casiot Corinne

Thiol-functionalized silica powder allowed single-step purification of antimony for exploring stable Sb isotope signatures in the environment.


2021 ◽  
Vol 17 ◽  
Author(s):  
Bambang Susilo ◽  
Abd. Rohim ◽  
Midia Lestari W. H.

Background: S. cristaefolium is the brown seaweed extracted using the serial technique with different solvents. Methods: S. cristaefolium powder (50 mesh) was extracted with hexane, ethyl acetate, and methanol respectively. The S. cristaefolium powder residue had been dried before being re-extracted with the next different solvents. Three serial extracts were obtained and named as the 1-stage extract, 2-stage extract, and 3-stage extract. Besides, a single-step extract (extraction using only methanol) was also produced to compare with three serial extracts in antibacterial activity tests (against E. coli and S. aureus). The three serial extracts were detected their antibacterial compounds using GC-MS, LC-HRMS, and FT-IR. Results: The 3-stage extract had the highest extraction yield. On S. aureus, the inhibition zone in all extracts was not significantly different. On E.coli, the highest inhibition zone (5.42±0.14 mm) was the 3-stage extract, indeed it is higher than both antibiotic and a single-step extract. Phenol, 9-Tricosene(Z)-, palmitic acid, and oleamide were contained in all extracts. Other antibacterial compound types, both the 1-stage and 2-stage extracts contained 8 types whilst the 3-stage extract contained the most types (12 types). Particularly, hexyl cinnamic aldehyde and betaine were detected only in the 3-stage extract with the dominant area. The carboxylic acid groups were detected in all extracts to confirm the fatty acid structure. Several cinnamic aldehyde groups were detected only in the 3-stage extract. Conclusions: Thus, the extraction technique serially could produce the 3-stage extract which has the strongest antibacterial activity and the richest antibacterial compounds.


2020 ◽  
Author(s):  
Veronica Peverelli ◽  
Tanya Ewing ◽  
Daniela Rubatto ◽  
Martin Wille ◽  
Alfons Berger ◽  
...  

Abstract. Monoclinic epidote is a low-µ (µ = 283U / 204Pb) mineral occurring in a variety of geological environments, participating in many metamorphic reactions and stable throughout a wide range of pressure–temperature conditions. Despite containing fair amounts of U, its use as a U–Pb geochronometer has been hindered by the commonly high contents of initial Pb with isotopic compositions that cannot be assumed a priori. We present U–Pb geochronology of hydrothermal-vein epidote spanning a wide range of Pb (3.9–190 µg g−1), Th (0.009–38 µg g−1) and U (2.6–530 µg g−1) contents and with µ values between 7–510 from the Albula area (eastern Swiss Alps), from the Grimsel area (central Swiss Alps) and from the Heyuan fault (Guangdong province, China). The investigated epidote samples show appreciable fractions of initial Pb that vary to different extents. A protocol has been developed for in situ U–Pb dating of epidote by spot-analysis laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) with a magmatic allanite as primary reference material. The suitability of the protocol and the reliability of the measured isotopic ratios have been ascertained by independent measurements of 238U / 206Pb and 207Pb / 206Pb ratios respectively by quadrupole and multicollector ICP–MS applied to epidote micro-separates digested and diluted in acids. For age calculation, we used the Tera–Wasserburg (207Pb / 206Pb–238U / 206Pb) diagram, which does not require corrections for initial Pb and provides the initial 207Pb / 206Pb ratio if all intra-sample analyses are co-genetic. Petrographic and microstructural data indicate that the calculated ages date the crystallization of vein epidote from a hydrothermal fluid and that the U–Pb system was not reset to younger ages by later events. Vein epidote from the Albula area formed in the Paleocene (62.7 ± 3.0 Ma) and is related to Alpine greenschist-facies metamorphism. The Miocene (19.1 ± 4.0 Ma and 16.9 ± 3.7 Ma) epidote veins from the Grimsel area formed during the Handegg phase (22–17 Ma) of the Alpine evolution of the Aar Massif. Identical initial 207Pb / 206Pb ratios reveal homogeneity in Pb isotopic compositions of the fluid across ca. 200 m. Vein epidote from the Heyuan fault is Cretaceous in age (108.1 ± 8.4 Ma) and formed during the early movements of the fault. In situ U–Pb analyses of epidote returned reliable ages of otherwise undatable epidote-quartz veins. The Tera–Wasserburg approach has proven pivotal for in situ U–Pb dating of epidote and the decisive aspect for low age uncertainties is the variability in intra-sample initial Pb fractions.


Author(s):  
Colin Ferrari ◽  
Eléonore Resongles ◽  
Rémi Freydier ◽  
Corinne Casiot

Correction for ‘A single-step purification method for the precise determination of the antimony isotopic composition of environmental, geological and biological samples by HG-MC-ICP-MS’ by Colin Ferrari et al., J. Anal. At. Spectrom., 2021, 36, 776–785, DOI: "https://doi.org/10.1039/D0JA00452A">10.1039/D0JA00452A.


2018 ◽  
Vol 33 (2) ◽  
pp. 175-186 ◽  
Author(s):  
Leah E. Morgan ◽  
Danielle P. Santiago Ramos ◽  
Brett Davidheiser-Kroll ◽  
John Faithfull ◽  
Nicholas S. Lloyd ◽  
...  

Potassium isotopic compositions measured by MC-ICP-MS in cold-plasma, high-resolution mode indicate terrestrial variability in 41K/39K ratios.


2018 ◽  
Vol 33 (11) ◽  
pp. 1932-1940 ◽  
Author(s):  
Hongyan Geng ◽  
Runsheng Yin ◽  
Xiangdong Li

Optimized gas flows achieved the direct determination of Hg isotopic compositions of 0.1 ng mL−1 solutions.


Author(s):  
Shiho Asai ◽  
Keisuke Okumura ◽  
Yukiko Hanzawa ◽  
Hideya Suzuki ◽  
Masaaki Toshimitsu ◽  
...  

Correlations between Nd isotopes and difficult-to-measure (DTM) nuclides, such as Se-79, Tc-99, Sn-126, and Cs-135, predicted using a calculation code have been validated by postirradiation examination (PIE). The calculation was performed with a burnup calculation code, MVP-BURN, using the updated nuclear data library JENDL-4.0. An irradiated PWR fuel with a burnup of 44.9 GWd/t and a cooling time of 7458 days was used as a standard sample. The concentrations of Nd isotopes in the sample solutions were determined by inductively coupled plasma mass spectrometry (ICP-MS) after purification by two consecutive anion-exchange separations. The ratios of Se-79 and Cs-135 to Nd isotopes (Nd-145, Nd-146, and Nd-145+Nd-146) calculated using MVP-BURN were in good agreement with PIE values within the deviations of 8% and 6%, respectively. This indicates that these calculated ratios are applicable to the scaling factors of Se-79 and Cs-135. For Tc-99 and Sn-126, the calculated values were respectively about 50% and 20% higher than the PIE values. These overestimations were mainly caused by the lack of the contribution of an insoluble residue to the measured concentrations.


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