Next Article in Journal
A Novel Hard Decision Based Simultaneous Target Tracking and Classification Approach
Next Article in Special Issue
Using a Mobile Device “App” and Proximal Remote Sensing Technologies to Assess Soil Cover Fractions on Agricultural Fields
Previous Article in Journal
Characterization of the Body-to-Body Propagation Channel for Subjects during Sports Activities
Previous Article in Special Issue
Two Solutions of Soil Moisture Sensing with RFID for Landslide Monitoring
Article Menu
Issue 2 (February) cover image

Export Article

Open AccessArticle
Sensors 2018, 18(2), 621; https://doi.org/10.3390/s18020621

Comparative Study of the Detection of Chromium Content in Rice Leaves by 532 nm and 1064 nm Laser-Induced Breakdown Spectroscopy

1,2,†
,
1,2,†
,
1
,
1
,
3
,
1
,
1
and
1,2,*
1
College of Biosystems Engineering and Food science, Zhejiang University, Hangzhou 310058, China
2
Key Laboratory of Spectroscopy Sensing, Ministry of Agriculture, Hangzhou 310058, China
3
School of Information Engineering, Zhejiang A & F University, Linan 311300, China
These authors contribute equally to this work.
*
Author to whom correspondence should be addressed.
Received: 13 December 2017 / Revised: 4 February 2018 / Accepted: 13 February 2018 / Published: 18 February 2018
(This article belongs to the Special Issue Sensors in Agriculture)
Full-Text   |   PDF [4540 KB, uploaded 24 February 2018]   |  

Abstract

Fast detection of toxic metals in crops is important for monitoring pollution and ensuring food safety. In this study, laser-induced breakdown spectroscopy (LIBS) was used to detect the chromium content in rice leaves. We investigated the influence of laser wavelength (532 nm and 1064 nm excitation), along with the variations of delay time, pulse energy, and lens-to-sample distance (LTSD), on the signal (sensitivity and stability) and plasma features (temperature and electron density). With the optimized experimental parameters, univariate analysis was used for quantifying the chromium content, and several preprocessing methods (including background normalization, area normalization, multiplicative scatter correction (MSC) transformation and standardized normal variate (SNV) transformation were used to further improve the analytical performance. The results indicated that 532 nm excitation showed better sensitivity than 1064 nm excitation, with a detection limit around two times lower. However, the prediction accuracy for both excitation wavelengths was similar. The best result, with a correlation coefficient of 0.9849, root-mean-square error of 3.89 mg/kg and detection limit of 2.72 mg/kg, was obtained using the SNV transformed signal (Cr I 425.43 nm) induced by 532 nm excitation. The results indicate the inspiring capability of LIBS for toxic metals detection in plant materials. View Full-Text
Keywords: rice leaves; chromium content; laser-induced breakdown spectroscopy; laser wavelength; preprocessing methods rice leaves; chromium content; laser-induced breakdown spectroscopy; laser wavelength; preprocessing methods
Figures

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Peng, J.; Liu, F.; Shen, T.; Ye, L.; Kong, W.; Wang, W.; Liu, X.; He, Y. Comparative Study of the Detection of Chromium Content in Rice Leaves by 532 nm and 1064 nm Laser-Induced Breakdown Spectroscopy. Sensors 2018, 18, 621.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top