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Lv XJ, Wang Y, Cai C, Pang SF, Ma JB, Zhang YH. Investigation of gel formation and volatilization of acetate acid in magnesium acetate droplets by the optical tweezers. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 200:179-185. [PMID: 29680496 DOI: 10.1016/j.saa.2018.04.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 04/06/2018] [Accepted: 04/13/2018] [Indexed: 06/08/2023]
Abstract
Hygroscopicity and volatility of single magnesium acetate (MgAc2) aerosol particles at various relative humidities (RHs) are studied by a single-beam optical tweezers, and refractive indices (RIs) and morphology are characterized by cavity enhanced Raman spectroscopy. Gel formation and volatilization of acetate acid (HAc) in MgAc2 droplets are observed. Due to the formation of amorphous gel structure, water transposition in droplets at RH < 50% is significantly impeded on a time scale of 140,000 s. Different phase transition at RH < 10% is proposed to explain the distinct water loss after the gel formation. To compare volatilization of HAc in different systems, MgAc2 and sodium acetate (NaAc) droplets are maintained at several different stable RHs during up to 86,000 s. At RH ≈ 74%, magnesium hydroxide (Mg(OH)2) inclusions are formed in MgAc2 droplets due to the volatilization of HAc, and whispering gallery modes (WGMs) of MgAc2 droplets in the Raman spectrum quench after 50,000 s. In sharp contrast, after 86,000 s at RH ≈ 70%, NaAc droplets are in well-mixed liquid states, containing soluble sodium hydroxide (NaOH). At this state, the RI of NaAc droplet is increased, and the quenching of WGMs is not observable.
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Affiliation(s)
- Xi-Juan Lv
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Yang Wang
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Chen Cai
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Shu-Feng Pang
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Jia-Bi Ma
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
| | - Yun-Hong Zhang
- The Institute of Chemical Physics, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
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Fong BN, Kennon JT, Ali HM. Mole Ratio Dependence of the Mutual Deliquescence Relative Humidity of Aqueous Salts of Atmospheric Importance. J Phys Chem A 2016; 120:3596-601. [DOI: 10.1021/acs.jpca.6b02706] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bryant N. Fong
- Department
of Chemistry and
Physics, Arkansas State University, Jonesboro, Arkansas 72404, United States
| | - James T. Kennon
- Department
of Chemistry and
Physics, Arkansas State University, Jonesboro, Arkansas 72404, United States
| | - Hashim M. Ali
- Department
of Chemistry and
Physics, Arkansas State University, Jonesboro, Arkansas 72404, United States
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Schindelholz E, Tsui LK, Kelly RG. Hygroscopic Particle Behavior Studied by Interdigitated Array Microelectrode Impedance Sensors. J Phys Chem A 2013; 118:167-77. [DOI: 10.1021/jp4098149] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eric Schindelholz
- University of Virginia, 395 McCormick Road, P.O. Box 400745, Charlottesville, Virginia 22904, United States
| | - Lok-kun Tsui
- University of Virginia, 395 McCormick Road, P.O. Box 400745, Charlottesville, Virginia 22904, United States
| | - Robert G. Kelly
- University of Virginia, 395 McCormick Road, P.O. Box 400745, Charlottesville, Virginia 22904, United States
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Goswami N, Sahai A. Structural Evolution of Nickel Doped Zinc Oxide Nanostructures. ACTA ACUST UNITED AC 2013. [DOI: 10.1557/opl.2013.960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTIn this article, structural evolution in nickel doped zinc oxide nanostructures is reported. The ZnO nanostructures are synthesized with 1-10% of Ni doping adopting a chemical precipitation method. The undoped and doped nanostructures thus prepared, were systematically investigated employing X-ray diffraction (XRD), transmission and scanning electron microscopy (TEM/SEM), Fourier transform infrared (FTIR) and micro-Raman spectroscopy (μRS). The identification of wurtzite phase and determination of lattice parameters of Ni doped ZnO nanocrystallites is ascertained through XRD analysis. TEM/SEM images reveal the structural alteration of ZnO with variation of Ni doping concentrations. The study of vibrational modes of nanostructures at different stages of structural transformation, as performed through FTIR and Raman spectroscopy, assist in deciphering the crucial role of Ni doping concentration in gradual evolution of nickel doped ZnO structure from nanoparticles to nanorods.
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Ofner J, Krüger HU, Zetzsch C. Time Resolved Infrared Spectroscopy of Formation and Processing of Secondary Organic Aerosol. ACTA ACUST UNITED AC 2010. [DOI: 10.1524/zpch.2010.6146] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
An aerosol flow reactor was coupled to an infrared absorption cell to study aerosol formation processes with high temporal resolution. The recorded infrared spectra were referenced using aerosol smog chamber experiments. Evaluation was done by studying the formation of secondary organic aerosol from α-pinene and catechol as precursors and ozone as oxidant. Three main infrared absorptions: ν(O-H), ν(C-H) and ν(C=O) were considered, and humic like properties of the secondary organic aerosol are mainly interpreted according to the formation and variations of carbonyl bands in the region between 1850 and 1600 cm−1, especially the ν(C=O) of aryl carbonyls from catechol oxidation products below 1700 cm−1. The relative intensities of two major ν(C=O) stretching vibrations at 1690 cm−1 and 1755 cm−1 were observed to depend strongly on the available ozone concentration. At high precursor/ozone ratios (2:1 or 1:1) the vibration at 1690 cm−1 predominates, indicating aryl carbonyl vibrations. With increasing ozone concentrations this vibration is replaced by the higher carbonyl vibration at 1755 cm−1 indicating unsaturated carbonyl-containing compounds. This is a strong hint at ring opening processes leading to unsaturated aliphatic compounds in the resulting particle. Aryl carbonyls and aromatic or olefinic ν(C=C) at 1620 cm−1 in aged particles remain visible, as aerosol smog chamber studies exhibit – thus a strong hint at humic like properties of the SOA from the spectroscopic point of view.
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Affiliation(s)
- J. Ofner
- University of Bayreuth, Atmospheric Chemistry Research Laboratory, Bayreuth, Deutschland
| | - H.-U. Krüger
- University of Bayreuth, Atmospheric Chemistry Research Laboratory, Bayreuth, Deutschland
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Wang LY, Ding F, Zhang YH, Zhao LJ, Hu YA. Anomalous hygroscopic growth of fine particles of MgSO4 aerosols investigated by FTIR/ATR spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 71:682-687. [PMID: 18321774 DOI: 10.1016/j.saa.2008.01.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 01/06/2008] [Accepted: 01/12/2008] [Indexed: 05/26/2023]
Abstract
This paper demonstrates an approach for investigating the hygroscopic growth of MgSO4 aerosols deposited on ZnSe substrate by using attenuated total reflection Fourier transform infrared (FTIR/ATR) spectroscopy. The experimental setup based upon a refitted standard FTIR/ATR accessory was adopted for the hygroscopic study of aerosols. It has been found that the "predeliquescence" of fine MgSO4 aerosol particles with the mean spreading diameter around 500 nm occurred before roughly 15% RH. In contrast, the abrupt water absorption of coarse MgSO4 particles with the mean diameter larger than about 10 microm was reported to occur at roughly 42% RH, which was reproduced in this study. Up to now, both theoretical and experimental investigations were rare and immature for fine particles, but the method we used in this study worked very well for the fine particles of MgSO4 aerosols. It has been found that the possible reason for the "predeliquescence" fine particles of MgSO4 aerosols is that the initial state or phase of fine particles is different from coarse ones after desiccation. This research demonstrates that the approach based on the ATR technique is very convenient, accurate and requires only a little amount of lab supplies.
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Affiliation(s)
- Liang-Yu Wang
- The Institute for Chemical Physics, Beijing Institute of Technology, Beijing 100081, PR China
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Wang F, Zhao L, Zhang Y. Crystallization dynamics of supersaturated NaClO4 aerosols studied by high-speed photography. Sci Bull (Beijing) 2008. [DOI: 10.1007/s11434-008-0284-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Atmospheric heterogeneous reaction of acetone: Adsorption and desorption kinetics and mechanisms on SiO2 particles. Sci Bull (Beijing) 2008. [DOI: 10.1007/s11434-007-0489-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Zhao LJ, Wang F, Zhang K, Zeng QX, Zhang YH. Deliquescence and Efflorescence Processes of Aerosol Particles Studied byin situFTIR and Raman Spectroscopy. CHINESE J CHEM PHYS 2008. [DOI: 10.1088/1674-0068/21/01/1-11] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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10
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FTIR-ATR in situ observation on the efflorescence and deliquescence processes of Mg(NO3)2 aerosols. ACTA ACUST UNITED AC 2008. [DOI: 10.1007/s11426-007-0059-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Schuttlefield J, Al-Hosney H, Zachariah A, Grassian VH. Attenuated total reflection fourier transform infrared spectroscopy to investigate water uptake and phase transitions in atmospherically relevant particles. APPLIED SPECTROSCOPY 2007; 61:283-92. [PMID: 17389068 DOI: 10.1366/000370207780220868] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
In this study, attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopy is used to investigate water uptake and phase transitions for atmospherically relevant particles. Changes in the ATR-FT-IR spectra of NaCl, NH(4) NO(3), (NH(4))(2)SO(4), Ca(NO(3))(2), and SiO(2) as a function of relative humidity (RH) are presented and discussed. For these various particles, water can (1) become adsorbed on the particle surface; and/or (2) become absorbed in the particle structure to form a hydrate salt; and/or (3) become absorbed by the particle to form a liquid solution. Spectral features and analyses that distinguish these various processes are discussed. For the salts that do undergo a solid to liquid phase transition (deliquescence), excellent agreement is found between the measurements made here with ATR-FT-IR spectroscopy, a relatively simple, inexpensive, and readily available analytical tool, compared to more expensive, elaborate aerosol flow reactor systems using tandem differential mobility analyzers. In addition, for particles that adsorb water, we show here the utility of coupling ATR-FT-IR measurements with simultaneous quartz crystal microbalance (QCM) measurements. This coupling allows for the quantification of the amount of water associated with the particle as a function of relative humidity (f(RH)) along with the spectroscopic data.
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