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Liu R, Guo Y, Li M, Li J, Yang D, Hou K. Development and Application of a Chemical Ionization Focusing Integrated Ionization Source TOFMS for Online Detection of OVOCs in the Atmosphere. Molecules 2023; 28:6600. [PMID: 37764379 PMCID: PMC10535867 DOI: 10.3390/molecules28186600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/11/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Single photon ionization (SPI) based on vacuum ultraviolet (VUV) lamps has been extensively investigated and applied due to its clean mass spectra as a soft ionization method. However, the photon energy of 10.6 eV and photon flux of 1011 photons s-1 of a commercial VUV lamp limits its range of ionizable analytes as well as its sensitivity. This work designs a chemical ionization focusing integrated (CIFI) ionization source time-of-flight mass spectrometry (TOFMS) based on a VUV lamp for the detection of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs). The photoelectrons obtained from the VUV lamp via the photoelectric effect ionized the oxygen and water in the air to obtain the reagent ions. The ion-molecule-reaction region (IMR) is constituted by a segmented quadrupole that radially focuses the ions using a radio-frequency electric field. This significantly enhances the yield and transport efficiency of the product ions leading to a great improvement in sensitivity. As a result, a 44-fold and 1154-fold increase in the signal response for benzene and pentanal were achieved, respectively. To verify the reliability of the ionization source, the linear correspondence and repeatability of benzene and pentanal were investigated. Satisfactory dynamic linearity was obtained in the mixing ratio range of 5-50 ppbv, and the relative standard deviation (RSD) of inter-day reached 3.91% and 6.26%, respectively. Finally, the CIFI-TOFMS was applied to the determination of OVOCs, and the LOD of 12 types of OVOCs reached the pptv level, indicating that the ionization source has the potential for accurate and sensitive online monitoring of atmospheric OVOCs.
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Affiliation(s)
- Ruidong Liu
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Yingzhe Guo
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Mei Li
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Jing Li
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Dong Yang
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Keyong Hou
- Environment Research Institute, Shandong University, Qingdao 266237, China
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Yan Z, Shan L, Cheng S, Yu Z, Wei Z, Wang H, Sun H, Yang B, Shu J, Li Z. A Simple High-Flux Switchable VUV Lamp Based on an Electrodeless Fluorescent Lamp for SPI/PAI Mass Spectrometry. Anal Chem 2023; 95:11859-11867. [PMID: 37474253 DOI: 10.1021/acs.analchem.3c01021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
Single-photon ionization (SPI) is a unique soft ionization technique for organic analysis. A convenient high-flux vacuum ultraviolet (VUV) light source is a key precondition for wide application of SPI techniques. In this study, we present a novel VUV lamp by simply modifying an ordinary electrodeless fluorescent lamp. By replacing the glass bulb with a stainless steel bulb and introducing 5% Kr/He (v/v) as the excitation gas, an excellent VUV photon flux over 4.0 × 1014 photons s-1 was obtained. Due to its rapid glow characteristics, the VUV lamp can be switched on and off instantly as required by detection, ensuring the stability and service life of the lamp. To demonstrate the performance of the new lamp, the switchable VUV lamp was coupled with an SPI-mass spectrometer, which could be changed to photoinduced associative ionization (PAI) mode by doping gaseous CH2Cl2 to initiate an associative ionization reaction. Two types of volatile organic compounds sensitive to SPI and PAI, typically benzene series and oxygenated organics, respectively, were selected as samples. The instrument exhibited a high detection sensitivity for the tested compounds. With a measurement time of 11 s, the 3σ limits of detection ranged from 0.33 to 0.75 pptv in SPI mode and from 0.03 to 0.12 pptv in PAI mode. This study provides an extremely simple method to assemble a VUV lamp with many merits, e.g., portability, robustness, durability, low cost, and high flux. The VUV lamp may contribute to the development of SPI-related highly sensitive detection technologies.
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Affiliation(s)
- Zitao Yan
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Lixin Shan
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Shiyu Cheng
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Zhangqi Yu
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Zhiyang Wei
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Haijie Wang
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Haohang Sun
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Bo Yang
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Jinian Shu
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
| | - Zhen Li
- Research Center for Environmental Material and Pollution Control Technology, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, Beijing 101408, People's Republic of China
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Abstract
Combustion is a reactive oxidation process that releases energy bound in chemical compounds used as fuels─energy that is needed for power generation, transportation, heating, and industrial purposes. Because of greenhouse gas and local pollutant emissions associated with fossil fuels, combustion science and applications are challenged to abandon conventional pathways and to adapt toward the demand of future carbon neutrality. For the design of efficient, low-emission processes, understanding the details of the relevant chemical transformations is essential. Comprehensive knowledge gained from decades of fossil-fuel combustion research includes general principles for establishing and validating reaction mechanisms and process models, relying on both theory and experiments with a suite of analytic monitoring and sensing techniques. Such knowledge can be advantageously applied and extended to configure, analyze, and control new systems using different, nonfossil, potentially zero-carbon fuels. Understanding the impact of combustion and its links with chemistry needs some background. The introduction therefore combines information on exemplary cultural and technological achievements using combustion and on nature and effects of combustion emissions. Subsequently, the methodology of combustion chemistry research is described. A major part is devoted to fuels, followed by a discussion of selected combustion applications, illustrating the chemical information needed for the future.
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Guo Y, Wang H, Yang B, Shu J, Jiang K, Yu Z, Zhang Z, Li Z, Huang J, Wei Z. An ultrasensitive SPI/PAI ion source based on a high-flux VUV lamp and its applications for the online mass spectrometric detection of sub-pptv sulfur ethers. Talanta 2022; 247:123558. [DOI: 10.1016/j.talanta.2022.123558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 04/29/2022] [Accepted: 05/14/2022] [Indexed: 10/18/2022]
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Dang M, Liu R, Dong F, Liu B, Hou K. Vacuum ultraviolet photoionization on-line mass spectrometry: instrumentation developments and applications. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Jiang L, Fu X, Zhou Z, Zhang C, Li J, Qi F, Fan X, Zhang G. Study of the thermal decomposition mechanism of FOX-7 by molecular dynamics simulation and online photoionization mass spectrometry. RSC Adv 2020; 10:21147-21157. [PMID: 35518768 PMCID: PMC9054391 DOI: 10.1039/d0ra03443f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 05/15/2020] [Indexed: 11/25/2022] Open
Abstract
The thermal decomposition mechanism of energetic materials is important for analyzing the combustion mechanisms of propellants and evaluating the safety of propellants during transport and storage. 1,1-Diamino-2,2-dinitroethylene (FOX-7) is an important insensitive energetic material that can be used as an oxidizer in propellants. However, the initial decomposition mechanism of FOX-7 is not clear to date. The ReaxFF molecular dynamics method is widely used in the investigation of the thermal decomposition mechanisms of energetic materials. Meanwhile, the combination of thermogravimetry with online photoionization time-of-flight mass spectrometry (TG-PI-TOF-MS) and online single-photon ionization time-of-flight mass spectrometry (SPI-TOF-MS) can reveal the decomposition products, which may be integrated with the results of the simulation. In this study, the primary thermal decomposition mechanism of 1,1-diamino-2,2-dinitroethylene (FOX-7) was studied by the ReaxFF molecular dynamics simulations and online photoionization mass spectrometry. The results of the molecular dynamics simulations showed that the primary decomposition step of FOX-7 is C–NO2 cleavage; after this, C
Created by potrace 1.16, written by Peter Selinger 2001-2019
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O formation occurs via a three-membered ring transition state, followed by NO elimination. The remaining structure loses NH2 and H, resulting in the formation of the NHCCO structure, which finally breaks down into HNC and CO. NH2 reacts with an H atom to produce NH3. A reversible intramolecular hydrogen transfer was also observed at 2500 K; however, it failed to dominate the decomposition reaction. During the decomposition of FOX-7, the major products are N2, NH3, CO2, and H2N2 and the minor products are H2O, HN2, and H2. The TG-PI-TOF-MS spectrum shows three signals, i.e., m/z = 18, 28, and 30, which can be assigned to H2O, CO, and NO, respectively. Moreover, four signals at m/z = 72.72, 55.81, 45.79, and 29.88 corresponding to the products (NH2)2CCO, (NH2)CCO, NO2, and NO have been obtained in the SPI-TOF-MS spectrum. The experimental data obtained via online photoionization mass spectrometry further validated the results of the molecular dynamics simulations. In this work, the primary thermal decomposition mechanism of 1,1-diamino-2,2-dinitroethylene (FOX-7) was studied by ReaxFF molecular dynamics simulations and online photoionization mass spectrometry.![]()
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Affiliation(s)
- Liping Jiang
- Xi'an Modern Chemistry Research Institute Xi'an 710065 PR China
| | - Xiaolong Fu
- Xi'an Modern Chemistry Research Institute Xi'an 710065 PR China
| | - Zhongyue Zhou
- Key Laboratory for Power Machinery and Engineering of Ministry of Education (MOE), Shanghai Jiao Tong University Shanghai 200240 PR China
| | - Chongmin Zhang
- Xi'an Modern Chemistry Research Institute Xi'an 710065 PR China
| | - Jizhen Li
- Xi'an Modern Chemistry Research Institute Xi'an 710065 PR China
| | - Fei Qi
- Key Laboratory for Power Machinery and Engineering of Ministry of Education (MOE), Shanghai Jiao Tong University Shanghai 200240 PR China
| | - Xuezhong Fan
- Xi'an Modern Chemistry Research Institute Xi'an 710065 PR China
| | - Guofang Zhang
- Key Laboratory of Applied Surface and Colloid Chemistry, MOE, School of Chemistry and Chemical Engineering, Shaanxi Normal University Xi'an 710062 PR China
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Wu H, Yuan C, Zhang H, Yang G, Cui C, Yang M, Bian W, Fu H, Luo Z, Yao J. Ultrafast Deep-Ultraviolet Laser Ionization Mass Spectrometry Applicable To Identify Phenylenediamine Isomers. Anal Chem 2018; 90:10635-10640. [DOI: 10.1021/acs.analchem.8b03167] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Haiming Wu
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chengqian Yuan
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hanyu Zhang
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Guanhua Yang
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chaonan Cui
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Mengzhou Yang
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Wensheng Bian
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hongbing Fu
- Department of Chemistry, Capital Normal University, Beijing 100048, P. R. China
| | - Zhixun Luo
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jiannian Yao
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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Huang Q, Liu C, Wei R, Wang J. Experimental study of polyethylene pyrolysis and combustion over HZSM-5, HUSY, and MCM-41. JOURNAL OF HAZARDOUS MATERIALS 2017; 333:10-22. [PMID: 28340385 DOI: 10.1016/j.jhazmat.2017.03.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 02/07/2017] [Accepted: 03/12/2017] [Indexed: 06/06/2023]
Abstract
The effects of temperatures, catalysts, and catalyst contents on polyethylene (PE) pyrolysis were investigated by using single-photon ionization time-of-flight mass spectrometry (SPI-TOFMS). The mass spectra of pyrolyzed PE and PE/catalysts from 300°C to 800°C illustrate that the pyrolysis reactions were apparently promoted and varied by introducing HZSM-5, HUSY, and MCM-41. As microporous catalysts, HZSM-5 and HUSY were found to accelerate the BTX formation at 400°C, which could not be observed for pure PE until 800°C. With the existence of MCM-41, only alkenes were produced below 600°C. The pyrolysis processes could to be accelerated by adding catalysts. Principal components analysis (PCA) was finally employed to identify the main factors with influence on the products distribution. Analytical results showed that the yield of the majority of products could be affected by different experimental conditions, that the type of catalysts makes the most significant influence. The impact of different types of catalysts on fire hazard of PE was studied by using the cone calorimeter. The results indicated that the time to ignition (TTI) and the peak heat release rate (pHRR) were changed remarkably. It is worth noting that with the addition of MCM-41, the pHRR is the minimum.
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Affiliation(s)
- Que Huang
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, China
| | - Changcheng Liu
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, China.
| | - Ruichao Wei
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, China
| | - Jian Wang
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, China.
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9
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Luo Z. Deep Ultraviolet Single‐Photon Ionization Mass Spectrometry. Mass Spectrom (Tokyo) 2017. [DOI: 10.5772/68072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Wang YZ, Yang JZ, Pan Y, Ma H, Li YY, Qi F. On-Line Photoionization Mass Spectrometric Study on Behavior of Ammonia Poisoning on H-Form Ultra Stable Y Zeolite for Catalytic Pyrolysis of Polypropylene. CHINESE J CHEM PHYS 2016. [DOI: 10.1063/1674-0068/29/cjcp1604081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Yuan C, Liu X, Zeng C, Zhang H, Jia M, Wu Y, Luo Z, Fu H, Yao J. All-solid-state deep ultraviolet laser for single-photon ionization mass spectrometry. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:024102. [PMID: 26931868 DOI: 10.1063/1.4941841] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report here the development of a reflectron time-of-flight mass spectrometer utilizing single-photon ionization based on an all-solid-state deep ultraviolet (DUV) laser system. The DUV laser was achieved from the second harmonic generation using a novel nonlinear optical crystal KBe2BO3F2 under the condition of high-purity N2 purging. The unique property of this laser system (177.3-nm wavelength, 15.5-ps pulse duration, and small pulse energy at ∼15 μJ) bears a transient low power density but a high single-photon energy up to 7 eV, allowing for ionization of chemicals, especially organic compounds free of fragmentation. Taking this advantage, we have designed both pulsed nanospray and thermal evaporation sources to form supersonic expansion molecular beams for DUV single-photon ionization mass spectrometry (DUV-SPI-MS). Several aromatic amine compounds have been tested revealing the fragmentation-free performance of the DUV-SPI-MS instrument, enabling applications to identify chemicals from an unknown mixture.
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Affiliation(s)
- Chengqian Yuan
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Xianhu Liu
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Chenghui Zeng
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Hanyu Zhang
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Meiye Jia
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Yishi Wu
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhixun Luo
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Hongbing Fu
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Jiannian Yao
- Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
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Liu C, Zhu Y, Zhou Z, Yang J, Qi F, Pan Y. Ultrasonic nebulization extraction/low pressure photoionization mass spectrometry for direct analysis of chemicals in matrices. Anal Chim Acta 2015; 891:203-10. [PMID: 26388379 DOI: 10.1016/j.aca.2015.08.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 08/09/2015] [Indexed: 01/30/2023]
Abstract
A novel ultrasonic nebulization extraction/low-pressure photoionization (UNE-LPPI) system has been designed and employed for the rapid mass spectrometric analysis of chemicals in matrices. An ultrasonic nebulizer was used to extract the chemicals in solid sample and nebulize the solvent in the nebulization cell. Aerosols formed by ultrasonic were evaporated by passing through a transferring tube, and desolvated chemicals were ionized by the emitted light (10.6 eV) from a Krypton discharge lamp at low pressure (∼68 Pa). First, a series of semi/non-volatile compounds with different polarities, such as polycyclic aromatic hydrocarbons (PAHs), amino acids, dipeptides, drugs, nucleic acids, alkaloids, and steroids were used to test the system. Then, the quantification capability of UNE-LPPI was checked with: 1) pure chemicals, such as 9,10-phenanthrenequinone and 1,4-naphthoquinone dissolved in solvent; 2) soil powder spiked with different amounts of phenanthrene and pyrene. For pure chemicals, the correlation coefficient (R(2)) for the standard curve of 9,10-phenanthrenequinone in the range of 3 ng-20 μg mL(-1) was 0.9922, and the measured limits of detection (LOD) was 1 ng ml(-1). In the case of soil powder, linear relationships for phenanthrene and pyrene from 10 to 400 ng mg(-1) were obtained with correlation coefficients of 0.9889 and 0.9893, respectively. At last, the feasibility of UNE-LPPI for the detection of chemicals in real matrices such as tablets and biological tissues (tea, Citrus aurantium peel and sage (Salvia officinalis) leaf) were successfully demonstrated.
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Affiliation(s)
- Chengyuan Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Yanan Zhu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Zhongyue Zhou
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China; Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Jiuzhong Yang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China; Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Fei Qi
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China; Power Machinery and Engineering of Ministry of Education, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Yang Pan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China.
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