“Stat” methods in continuous flow analysis

1981 ◽  
Vol 123 ◽  
pp. 239-246 ◽  
Author(s):  
Herbert Weisz ◽  
Günter Fritz
2020 ◽  
Vol 155 ◽  
pp. 104731 ◽  
Author(s):  
Marcos Almeida Bezerra ◽  
Valfredo Azevedo Lemos ◽  
Djalma Menezes de Oliveira ◽  
Cleber Galvão Novaes ◽  
Jeferson Alves Barreto ◽  
...  

2021 ◽  
Author(s):  
Margaret Harlan ◽  
Helle Astrid Kjær ◽  
Tessa Vance ◽  
Paul Vallelonga ◽  
Vasileios Gkinis ◽  
...  

<p>The Mount Brown South (MBS) ice core is an approximately 300-meter-long ice core, drilled in 2016-2017 to the south of Mount Brown, Wilhelm II Land, East Antarctica. This location in East Antarctica was chosen as it produces an ice core with well-preserved sub-annual records of both chemistry and isotope concentrations, spanning back over 1000 years. MBS is particularly well suited to represent climate variations of the Indian Ocean sector of Antarctica, and to provide information about regional volcanism in the Southern Indian Ocean region.</p><p>A section of ice spanning the length of the MBS core was melted as part of the autumn 2019 continuous flow analysis (CFA) campaign at the Physics of Ice, Climate, and Earth (PICE) group at the University of Copenhagen. During this campaign, measurements were conducted for chemistry and impurities contained in the ice, in addition to water isotopes. The data measured in Copenhagen include measurements of H<sub>2</sub>O<sub>2,</sub> pH, electrolytic conductivity, and NH<sub>4</sub><sup>+</sup>, Ca<sup>2+</sup>, and Na<sup>+</sup> ions, in addition to insoluble particulate concentrations and size distribution measured using an Abakus laser particle counter.</p><p>Here, we present an overview of the CFA chemistry and impurity data, as well as preliminary investigations into the size distribution of insoluble particles and the presence of volcanic material within the ice. These initial chemistry and particulate size distribution data sets are useful in order to identify sections of the MBS core to subject to further analysis to increase our understanding of volcanic activity in the Southern Indian Ocean region.</p>


Transfusion ◽  
2017 ◽  
Vol 58 (2) ◽  
pp. 294-305 ◽  
Author(s):  
Cécile Toly-Ndour ◽  
Haifa Mourtada ◽  
Stéphanie Huguet-Jacquot ◽  
Emeline Maisonneuve ◽  
Stéphanie Friszer ◽  
...  

2018 ◽  
Vol 11 (8) ◽  
pp. 4725-4736 ◽  
Author(s):  
Elizabeth D. Keller ◽  
W. Troy Baisden ◽  
Nancy A. N. Bertler ◽  
B. Daniel Emanuelsson ◽  
Silvia Canessa ◽  
...  

Abstract. We describe a systematic approach to the calibration and uncertainty estimation of a high-resolution continuous flow analysis (CFA) water isotope (δ2H, δ18O) record from the Roosevelt Island Climate Evolution (RICE) Antarctic ice core. Our method establishes robust uncertainty estimates for CFA δ2H and δ18O measurements, comparable to those reported for discrete sample δ2H and δ18O analysis. Data were calibrated using a time-weighted two-point linear calibration with two standards measured both before and after continuously melting 3 or 4 m of ice core. The error at each data point was calculated as the quadrature sum of three factors: Allan variance error, scatter over our averaging interval (error of the variance) and calibration error (error of the mean). Final mean total uncertainty for the entire record is δ2H=0.74 ‰ and δ18O=0.21 ‰. Uncertainties vary through the data set and were exacerbated by a range of factors, which typically could not be isolated due to the requirements of the multi-instrument CFA campaign. These factors likely occurred in combination and included ice quality, ice breaks, upstream equipment failure, contamination with drill fluid and leaks or valve degradation. We demonstrate that our methodology for documenting uncertainty was effective across periods of uneven system performance and delivered a significant achievement in the precision of high-resolution CFA water isotope measurements.


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