A continuous stream flash evaporator for the calibration of an IR cavity ring-down spectrometer for the isotopic analysis water

TY - JOUR

T1 - A continuous stream flash evaporator for the calibration of an IR cavity ring-down spectrometer for the isotopic analysis water

AU - Gkinis, Vasileios

AU - Popp, Trevor James

AU - Johnsen, Sigfus Johann

AU - Blunier, Thomas

PY - 2010/12

Y1 - 2010/12

N2 - A new technique for high-resolution simultaneous isotopic analysis of δ18O and δD in liquid water is presented.Acontinuous stream flash evaporator has been designed that is able to vapourise a stream of liquid water in a continuous mode and deliver a stable and finely controlledwater vapour sample to a commercially available infrared cavity ring-down spectrometer. Injection of sub-microlitre amounts of the liquid water is achieved by pumping liquid water sample through a fused silica capillary and instantaneously vapourising it with 100% efficiency in a home-made oven at a temperature of 170 °C. The system's simplicity, low power consumption and low dead volume together with the possibility for automated unattended operation provides a solution for the calibration of laser instruments performing isotopic analysis of water vapour. Our work is mainly driven by the possibility to perform high-resolution online water isotopic analysis on continuous-flow analysis (CFA) systems typically used to analyse the chemical composition of ice cores drilled in polar regions. In the following, we describe the system's precision and stability and sensitivity to varying levels of sample size and we assess the observed memory effects. A test run with standard waters of different isotopic compositions is presented, demonstrating the ability to calibrate the spectrometer's measurements on a VSMOW scale with a relatively simple and fast procedure.

AB - A new technique for high-resolution simultaneous isotopic analysis of δ18O and δD in liquid water is presented.Acontinuous stream flash evaporator has been designed that is able to vapourise a stream of liquid water in a continuous mode and deliver a stable and finely controlledwater vapour sample to a commercially available infrared cavity ring-down spectrometer. Injection of sub-microlitre amounts of the liquid water is achieved by pumping liquid water sample through a fused silica capillary and instantaneously vapourising it with 100% efficiency in a home-made oven at a temperature of 170 °C. The system's simplicity, low power consumption and low dead volume together with the possibility for automated unattended operation provides a solution for the calibration of laser instruments performing isotopic analysis of water vapour. Our work is mainly driven by the possibility to perform high-resolution online water isotopic analysis on continuous-flow analysis (CFA) systems typically used to analyse the chemical composition of ice cores drilled in polar regions. In the following, we describe the system's precision and stability and sensitivity to varying levels of sample size and we assess the observed memory effects. A test run with standard waters of different isotopic compositions is presented, demonstrating the ability to calibrate the spectrometer's measurements on a VSMOW scale with a relatively simple and fast procedure.

U2 - 10.1080/10256016.2010.538052

DO - 10.1080/10256016.2010.538052

M3 - Journal article

SN - 1025-6016

VL - 46

SP - 463

EP - 475

JO - Isotopes in Environmental and Health Studies

JF - Isotopes in Environmental and Health Studies

IS - 4

ER -