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Abstract. The volatility of organic aerosols remains poorly understood due to the complexity of speciation and multiphase processes. In this study, we extracted humic-like substances (HULIS) from four atmospheric aerosol samples collected at the SORPES station in Nanjing, eastern China, and investigated the volatility behavior of particles at different sizes using a Volatility Tandem Differential Mobility Analyzer (VTDMA). In spite of the large differences in particle mass concentrations, the extracted HULIS from the four samples all revealed very high-oxidation states (O : C > 0.95), indicating secondary formation as the major source of HULIS in Yangtze River Delta (YRD). An overall low volatility was identified for the extracted HULIS, with the volume fraction remaining (VFR) higher than 55 % for all the regenerated HULIS particles at the temperature of 280 °C. A kinetic mass transfer model was applied to the thermodenuder (TD) data to interpret the observed evaporation pattern of HULIS, and to derive the mass fractions of semi-volatile (SVOC), low-volatility (LVOC) and extremely low-volatility components (ELVOC). The results showed that LVOC and ELVOC dominated (more than 80 %) the total volume of HULIS. Atomizing processes led to a size-dependent evaporation of regenerated HULIS particles, and resulted in more ELVOC in smaller particles. In order to understand the role of interaction between inorganic salts and atmospheric organic mixtures in the volatility of an organic aerosol, the evaporation of mixed samples of ammonium sulfate (AS) and HULIS was measured. The results showed a significant but nonlinear influence of ammonium sulfate on the volatility of HULIS. The estimated fraction of ELVOC in the organic part of the largest particles (145 nm) increased from 26 %, in pure HULIS samples, to 93 % in 1 : 3 (mass ratio of HULIS : AS) mixed samples, to 45 % in 2 : 2 mixed samples, and to 70 % in 3 : 1 mixed samples, suggesting that the interaction with ammonium sulfate tends to decrease the volatility of atmospheric organic compounds. Our results demonstrate that HULIS are important low-volatility, or even extremely low-volatility, compounds in the organic-aerosol phase. As important formation pathways of atmospheric HULIS, multiphase processes, including oxidation, oligomerization, polymerization and interaction with inorganic salts, are indicated to be important sources of low-volatility and extremely low-volatility species of organic aerosols.

This study was funded in part by the Sichuan Provincial Department of Education (No. 17ZB0169) Background: In this study, we evaluated the advantages and disadvantages of angioembolization in patients with Grade III-V blunt renal trauma compared with other treatments. Material/Methods: We prospectively collected data on patients hospitalized for Grade III-V blunt renal trauma. Organ damage was graded according to the American Association for the Surgery of Trauma (AAST) criteria. Initial grouping was then performed according to the hemodynamics and "initial treatment". The eligible patients were divided into 3 groups: conservative treatment group (Group A), arterial embolization group (Group B), and surgical group (Group C). The success rate, significance, and follow-up renal function were evaluated. Results: In Group B of Grade IV, estimated glomerular filtration rate (eGFR) and serum creatinine (Scr) levels were slightly decreased and increased, respectively, after embolization compared with before embolization (P=0.002, P=0.039). In Grade V, the eGFR of Group B after embolization was lower than before embolization (P=0.041); The levels of serum urea (Urea) and Scr in Group B after treatment were higher than those before treatment (P=0.042, P=0.024). Conservative treatment and angioembolization were better than exploration in protecting renal function of Grade IV (P=0.035 and P=0.047, respectively). Conclusions: The success rate of angioembolization was high and protected renal function to the greatest extent, and there were no differences in renal function at long-term follow-up. However, it is difficult to manage renal vessel laceration or avulsion by embolization alone, and various endovascular therapies are required to protect the function of residual kidneys.