Article
Chemistry, Physical
Paul E. Ohno, Lilliana Brandao, Elizabeth M. Rainone, Eleonora Aruffo, Junfeng Wang, Yiming Qin, Scot T. . Martin
Summary: This study investigated the size dependence of the relative humidity for liquid-liquid phase separation (LLPS) of aerosol particles. The results showed that the SRH values decreased by approximately 5% for submicron particles compared to supermicron particles. These observations help predict size-dependent LLPS in the atmosphere.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Engineering, Environmental
Fabian Mahrt, Elli Newman, Yuanzhou Huang, Markus Ammann, Allan K. Bertram
Summary: The research found that internal mixtures of POA and SOA in the atmosphere almost always formed two phases when the O/C ratio of the POA was less than 0.11. When the O/C ratio of the POA was between 0.11 and 0.29, the mixtures mostly resulted in particles with one liquid phase. However, depending on the types of SOA and POA surrogates, two liquid phases were also observed in some cases, and an increase in phase-separated particles was observed when increasing the relative humidity within this O/C range.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Environmental Sciences
Xiuli Wei, Haosheng Dai, Huaqiao Gui, Jiaoshi Zhang, Yin Cheng, Jie Wang, Yixin Yang, Youwen Sun, Jianguo Liu
Summary: This study utilizes Fourier transform infrared spectroscopy to characterize the hygroscopic growth properties and phase transition microdynamics of nanoparticles in real time. A novel real-time calculation method for aerosol liquid water content is developed using reconstructed absorption spectra of liquid water. The study also explores the phenomenon of lower deliquescence points in mixed nanoparticles compared to pure nanoparticles.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Environmental Sciences
Joseph Lilek, Andreas Zuend
Summary: Aerosol viscosity is influenced by mixture composition, temperature, and relative humidity. A new model, AIOMFAC-VISC, extends the group-contribution model to predict viscosity for aqueous electrolyte solutions and aqueous organic-inorganic mixtures. The model considers ion-specific expressions for electrolyte solutions and tested different mixing approaches for organic-inorganic mixtures. The predictions showed high accuracy and physical meaningfulness.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2022)
Article
Multidisciplinary Sciences
Zhe Xu, Theodore Hueckel, William T. M. Irvine, Stefano Sacanna
Summary: The research team has created non-biological capsules that can capture, concentrate, store, and release microscopic payloads as needed. This design uses hollow colloids as cell-membrane mimics with a well-defined single pore, allowing for mass production and offering a blueprint for developing smart materials, micro-machinery, and artificial cell mimics.
Article
Chemistry, Physical
Yeny A. Tobon, Danielle El Hajj, Samantha Seng, Ferdaous Bengrad, Myriam Moreau, Nicolas Visez, Isabelle Chiapello, Suzanne Crumeyrolle, Marie Choel
Summary: This study investigated the deliquescence relative humidity of internally mixed sodium chloride-ammonium sulfate coarse particles using an acoustic levitation system and a confocal Raman microscope. It was found that NH4Cl, Na2SO4 and NH4NaSO4 center dot 2H(2)O were formed in recrystallized particles and coexisted with NaCl and (NH4)(2)SO4. Significant discrepancies between the thermodynamic model E-AIM and the laboratory experiments were observed for certain NaCl mole fractions.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Environmental Sciences
Yu Wang, Aristeidis Voliotis, Yunqi Shao, Taomou Zong, Xiangxinyue Meng, Mao Du, Dawei Hu, Ying Chen, Zhijun Wu, M. Rami Alfarra, Gordon McFiggans
Summary: The phase behaviour of aerosol particles is influenced by relative humidity and chemical composition, showing a transition between liquid and nonliquid states as humidity and the organic-inorganic mass ratio increase. Real atmospheric consequences include the influence of changes in ambient humidity and organic-inorganic mass ratio on aerosol phase state.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Engineering, Environmental
Min Yao, Yue Zhao, Chongxuan Chang, Shunyao Wang, Ziyue Li, Chenxi Li, Arthur W. H. Chan, Huayun Xiao
Summary: This study investigates the reactions between SO2 and POs in monoterpene-derived secondary organic aerosol. The results show that the reactivity of PO-S(IV) is consistent with pure SOA when the particles are phase-separated, but varies substantially when the organic and inorganic phases are miscible. The measured kinetics suggest that the PO-S(IV) reaction is an important sulfate formation pathway in aerosols, with the reaction kinetics dominated by general acid catalysis.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Shoji Ishizaka, Chihiro Yamamoto, Himeka Yamagishi
Summary: This study investigated the equilibrium morphology of liquid-liquid phase-separated droplets in air using a temperature-responsive ionic liquid. The phase separation was induced by controlling the air relative humidity, leading to the formation of liquid-liquid phase-separated droplets of partially engulfed morphology. Comparison with a thermodynamic model showed that the observed configurations matched the calculated results.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Biochemical Research Methods
Christof Barth, Klaus-Peter Hinz, Bernhard Spengler
Summary: This article presents a method based on high-resolution atmospheric pressure laser desorption ionization mass spectrometry imaging and statistical analysis to analyze and characterize very small sample quantities without any sample preparation. The method was successfully demonstrated using filter samples from heavily polluted mega cities in Iran and China, and was able to distinguish between the two cities based on characteristic compounds.
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Bernadette Rosati, Sigurd Christiansen, Anders Dinesen, Pontus Roldin, Andreas Massling, E. Douglas Nilsson, Merete Bilde
Summary: The study found that ageing of liquid NaCl and artificial sea salt aerosol by exposure to ozone and UV light leads to a substantial decrease in hygroscopicity and cloud activation potential of the dried particles of the same size. Surface reactions on the liquid aerosols and the formation of salt structures with water bound within the dried aerosols, termed hydrates, are crucial for small particles during ageing.
SCIENTIFIC REPORTS
(2021)
Article
Meteorology & Atmospheric Sciences
Jiaoshi Zhang, Steven Spielman, Yang Wang, Guangjie Zheng, Xianda Gong, Susanne Hering, Jian Wang
Summary: This study introduces a prototype HFIMS that allows for fast measurements of aerosol hygroscopic growth at various RH levels, providing comprehensive characterizations of aerosol properties. By using a dual-channel humidifier and optimized measurement sequence, HFIMS can rapidly measure aerosol hygroscopic growth for six particle diameters under five RH levels, demonstrating its capability to capture the rapid evolution of aerosol properties.
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2021)
Article
Environmental Sciences
Minli Wang, Yiqun Chen, Heyun Fu, Xiaolei Qu, Guofeng Shen, Bengang Li, Dongqiang Zhu
Summary: The study found that the hygroscopicity of BC samples is largely determined by their composition, with the inorganic component significantly influencing the hygroscopicity of BC, while organic carbon and elemental carbon make smaller contributions to the hygroscopicity. By analyzing the hygroscopicity of different components at various relative humidity levels, the study revealed the hygroscopic mechanism of BC.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Chemistry, Physical
Shuichi B. Ushijima, Erik Huynh, Ryan D. Davis, Margaret A. Tolbert
Summary: Atmospheric aerosols are complex mixtures of inorganic and organic components. This study focused on the efflorescence of (NH4)2SO4/organic particles and found that poly(ethylene glycol) 400 did not inhibit seeded crystal growth, while raffinose inhibited heterogeneous efflorescence at lower humidities. Lower humidity led to increased viscosity, preventing the diffusion of water and ions, and thus inhibiting efflorescence of aerosols. The observed efflorescence at higher humidity suggests that collisions can induce efflorescence of mixed aerosols.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Meteorology & Atmospheric Sciences
Lekhendra Tripathee, Shichang Kang, Pengfei Chen, Hemraj Bhattarai, Junming Guo, Kundan Lal Shrestha, Chhatra Mani Sharma, Prakriti Sharma Ghimire, Jie Huang
Summary: The study collected aerosol samples in Dhulikhel in the Himalayas and found that ammonium nitrogen was the main component of water-soluble total nitrogen, with water-soluble organic nitrogen also contributing to the total. There were strong seasonal variations in aerosol and water-soluble nitrogen species concentrations, with higher levels during dry periods and lower levels during wet periods, mainly originating from the Indo-Gangetic Plain region.
ATMOSPHERIC RESEARCH
(2021)
