PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7645
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Article Citation - WoS: 6Citation - Scopus: 6First-Principles Study of Dissociation Processes for the Synthesis of Fe and Co Oxide Nanoparticles(American Chemical Society, 2018) Özdamar, Burak; Bouzid, Assil; Ori, Guido; Massobrio, Carlo; Boero, MauroThermal decomposition is a practical and reliable tool to synthesize nanoparticles with monodisperse size distribution and reproducible accuracy. The nature of the precursor molecules and their interaction with the environment during the synthesis process have a direct impact on the resulting nanoparticles. Our study focuses on widely used transition-metal (Co, Fe) stearates precursors and their thermal decomposition reaction pathway. We show how the nature of the metal and the presence or absence of water molecules, directly related to the humidity conditions during the synthesis process, affect the decomposition mechanism and the resulting transition-metal oxide building blocks. This, in turn, has a direct effect on the physical and chemical properties of the produced nanoparticles and deeply influences their composition and morphology.Article Citation - WoS: 49Citation - Scopus: 52Evaluation of a Conceptual Model for Gas-Particle Partitioning of Polycyclic Aromatic Hydrocarbons Using Polyparameter Linear Free Energy Relationships(American Chemical Society, 2016) Shahpoury, Pourya; Lammel, Gerhard; Albinet, Alexandre; Sofuoglu, Aysun; Dumanoğlu, Yetkin; Sofuoğlu, Sait Cemil; Wagner, Zdenek; Zdimal, VladimírA model for gas-particle partitioning of polycyclic aromatic hydrocarbons (PAHs) was evaluated using polyparameter linear free energy relationships (ppLFERs) following a multiphase aerosol scenario. The model differentiates between various organic (i.e., liquid water-soluble (WS)/organic soluble (OS) organic matter (OM), and solid/semisolid organic polymers) and inorganic phases of the particulate matter (PM). Dimethyl sulfoxide and polyurethane were assigned as surrogates to simulate absorption into the above-mentioned organic phases, respectively, whereas soot, ammonium sulfate, and ammonium chloride simulated adsorption processes onto PM. The model was tested for gas and PM samples collected from urban and nonurban sites in Europe and the Mediterranean, and the output was compared with those calculated using single-parameter linear free energy relationship (spLFER) models, namely Junge-Pankow, Finizio, and Dachs-Eisenreich. The ppLFER model on average predicted 96 ± 3% of the observed partitioning constants for semivolatile PAHs, fluoranthene, and pyrene, within 1 order of magnitude accuracy with root-mean-square errors (RMSE) of 0.35-0.59 across the sites. This was a substantial improvement compared to Finizio and Dachs-Eisenreich models (37 ± 17 and 46 ± 18% and RMSE of 1.03-1.40 and 0.94-1.36, respectively). The Junge-Pankow model performed better among spLFERs but at the same time showed an overall tendency for overestimating the partitioning constants. The ppLFER model demonstrated the best overall performance without indicating a substantial intersite variability. The ppLFER analysis with the parametrization applied in this study suggests that the absorption into WSOSOM could dominate the overall partitioning process, while adsorption onto salts could be neglected. (Figure Presented).
