| Title: | A multi-thermal-lens approach to evaluation of multi-pass probe beam configuration in thermal lens spectrometry |
|---|
| Authors: | ID Cabrera, Humberto, ICTP-Trieste, Italy (Author)
ID Goljat, Leja, UNG (Author)
ID Korte, Dorota, UNG (Author)
ID Marin, Ernesto, IPN-Mexico City, Mexico (Author)
ID Franko, Mladen, UNG (Author) |
|---|
| Files: |
This document has no files that are freely available to the public. This document may have a physical copy in the library of the organization, check the status via COBISS.  |
|---|
| Language: | English |
|---|
| Work type: | Not categorized |
|---|
| Typology: | 1.01 - Original Scientific Article |
|---|
| Organization: | UNG - University of Nova Gorica
|
|---|
| Abstract: | In this work, a recently proposed thermal lens instrument based on multi-pass probe beam concept is investigated and described as a multi-thermal-lens equivalent system. A simulation of the photothermal lens signal formation in a multi-thermal-lens equivalent configuration of the system is performed and validated by comparing the experimental signals of single, dual and ten-pass configurations to theoretically calculated values. The theoretically predicted enhancement of the signal is 9 to 10-fold for a weak thermal lens when comparing the ten-pass configuration with the conventional single-pass thermal lens system. Experimentally achieved signal enhancement in the ten-pass system is 8.3 for pure ethanol sample and between 8 and 9 for solutions with different concentrations of the Fe(II) - 1,10-Phenanthroline complex. Additionally, a value of 9.1 was calculated as the ratio of the slopes of the calibration lines obtained using the ten-pass and single-pass configurations. The achieved limit of detection for determination of Fe(II), in the ten-pass configuration, was 0.4 µgL-1, with a relative standard deviation around 4.5%, which compares favorably with previously reported results for TLS determination of Fe(II) in thin samples using low excitation power. For the multi-pass configuration the linear range of measurement is reduced when compared to the single-pass configuration. This is explained by the theoretical analysis of the photothermal signal under multi-pass condition, which shows the important contribution of the nonlinear term in the theoretical expression for the photothermal signal. The ten-pass configuration, which is presented and validated experimentally for the first time, offers important signal enhancement needed in recently developed TLS instruments with tunable, low power excitation sources. |
|---|
| Keywords: | Thermal lens spectrometry, Photothermal detection, Trace determination, Chemical sensor |
|---|
| Publication version: | Author Accepted Manuscript |
|---|
| Number of pages: | 9 |
|---|
| Numbering: | xxx |
|---|
| PID: | 20.500.12556/RUNG-4919-a6b11a1a-a026-4281-8d44-e3b4558510f3 |
|---|
| COBISS.SI-ID: | 5499131 |
|---|
| DOI: | https://doi.org/10.1016/j.aca.2019.12.009 |
|---|
| NUK URN: | URN:SI:UNG:REP:1EBGFAQJ |
|---|
| Publication date in RUNG: | 10.12.2019 |
|---|
| Views: | 4186 |
|---|
| Downloads: | 0 |
|---|
| Metadata: |    |
|---|
|
:
|
Copy citation |
|---|
| | | | Average score: | (0 votes) |
|---|
| Your score: | Voting is allowed only for logged in users. |
|---|
| Share: |  |
|---|
Hover the mouse pointer over a document title to show the abstract or click
on the title to get all document metadata. |
