Statistical Thermodynamic Description of Heteroaggregation between Anthropogenic Particulate Matter and Natural Particles in Aquatic Environments

2021 ◽  
Vol 5 (4) ◽  
pp. 980-989
Author(s):  
Robert M. Wheeler ◽  
Steven K. Lower
Keyword(s):  
Particulate Matter ◽  
Thermodynamic Description ◽  
Statistical Thermodynamic ◽  
Aquatic Environments

Thermodynamics of Defect Formation and Hydration of Y2O3

2012 ◽  
Vol 326-328 ◽  
pp. 126-131 ◽  
Author(s):  
L.P. Putilov ◽  
V.I. Tsidilkovski ◽  
A.N. Varaksin ◽  
Anatoly Yakovlevich Fishman
Keyword(s):  
Electronic Structure ◽  
Gas Phase ◽  
Defect Formation ◽  
Thermodynamic Description ◽  
Statistical Thermodynamic ◽  
Wide Range ◽  
F Center ◽  
Mechanical Approach ◽  
Quantum Mechanical Approach ◽  
F Centers

Defect formation in yttria with a small content of acceptor impurities in equilibrium with a hydrogen-containing gas phase is studied theoretically. A statistical-thermodynamic description of the yttriagas equilibrium is based on the approach developed for compounds with a complex electronic structure [Phys. Stat. Sol. B (1991) Vol. 168, p. 233]. The considered model of electronic structure for Y2O3 includes, besides valence and conduction bands, acceptor and F-center states. The energy of F-centers was calculated in the framework of the variational quantum-mechanical approach combined with the molecular statics method. It is shown that acceptor states appreciably affect the thermodynamics of defect formation, while the F-centers contribution in a wide range of external parameters is small. The concentrations of defects (protons, oxygen vacancies, electronic defects) and the Fermi level position are determined as functions of temperature and gas phase parameters.

scholarly journals Thermodynamic Formulations of Excess and Absolute Values of Adsorption on Solid Surfaces: A Comparison of One- and Two-Phase Approaches

1986 ◽  
Vol 3 (4) ◽  
pp. 271-291 ◽  
Author(s):  
H. Wittkopf ◽  
P. Bräuer
Keyword(s):  
High Pressures ◽  
Thermodynamic Description ◽  
Solid Surfaces ◽  
Statistical Thermodynamic ◽  
Two Phase ◽  
Phase Approach ◽  
Adsorption Analysis ◽  
Basic Concepts ◽  
The Difference ◽  
The One

The generally used methods of thermodynamic adsorption analysis are summarized in two basic concepts: the two-phase approach (which is an adequate picture of volume phase thermodynamics in adsorption) and the one-phase approach (which uses excess values for the thermodynamic description of adsorption). Differential and integral molar values of adsorption Δ a X̄ and Δ a X in the two-phase approach are not identical with the corresponding excess values Δ a X̄s and Δ a Xs in the one-phase approach. Especially at high temperatures and high pressures they may be entirely different. It is shown that the experimental methods most usually in adsorption thermodynamics (as adsorption volumetry and gravimetry) give excess data which are to be used in the one-phase approach but which can be transformed to the two-phase approach. Using statistical thermodynamic calculations the difference between these basic concepts is shown over a wide temperature range for the first virial coefficient, the internal energy and the heat capacity of adsorption.

Statistical thermodynamic description of H2 molecules in normal ortho/para mixture

2012 ◽  
Vol 37 (12) ◽  
pp. 9656-9668 ◽  
Author(s):  
Gianpiero Colonna ◽  
Antonio D'Angola ◽  
Mario Capitelli
Keyword(s):  
Thermodynamic Description ◽  
Statistical Thermodynamic

scholarly journals Strategies for determining heteroaggregation attachment efficiencies of engineered nanoparticles in aquatic environments

2020 ◽  
Vol 7 (2) ◽  
pp. 351-367 ◽  
Author(s):  
Antonia Praetorius ◽  
Elena Badetti ◽  
Andrea Brunelli ◽  
Arnaud Clavier ◽  
Julián Alberto Gallego-Urrea ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Suspended Particulate Matter ◽  
Engineered Nanoparticles ◽  
Theory And Practice ◽  
Aquatic Environments ◽  
Suspended Particulate

Heteroaggregation of engineered nanoparticles with suspended particulate matter in theory and practice: a roadmap for understanding and determining attachment efficiencies.

scholarly journals TlI and TlIII presence in suspended particulate matter: speciation analysis of thallium in wastewater

2015 ◽  
Vol 12 (3) ◽  
pp. 374 ◽  
Author(s):  
Natalia Ospina-Alvarez ◽  
Pawel Burakiewicz ◽  
Monika Sadowska ◽  
Beata Krasnodebska-Ostrega
Keyword(s):  
Particulate Matter ◽  
Suspended Particulate Matter ◽  
Speciation Analysis ◽  
Mining Area ◽  
Aquatic Environments ◽  
Dominant Form ◽  
Suspended Particulate ◽  
Speciation Study ◽  
Wastewater Samples ◽  
Polluted Wastewater

Environmental context Thallium occurs in the environment in two oxidation states, with TlIII being 1000-fold more toxic than TlI. We present a fractionation and speciation study of thallium in suspended particulate matter from highly polluted wastewater samples, and elucidate the dominant forms of thallium. Abstract Thallium (Tl) is a toxic element, whose toxicity is affected by its redox state. Compared with TlIII, TlI is thermodynamically more stable and less reactive; therefore in aquatic environments, dissolved thallium is mostly present as TlI. However, TlIII could be 1000 times more toxic than TlI. A combination of a fractionation and a speciation study carried out in highly polluted wastewater samples from a mining area in southern Poland in order to characterise chemical speciation of Tl in physically defined fractions is presented here. Total, particulate and dissolved thallium was determined. A leaching experiment based on forming TlIII complexed with diethylene triamine penta-acetic acid – a TlIII–DTPA complex – was performed in filters containing suspended particulate matter after single (0.45µm) and sequential filtration (15 + 0.45µm) of wastewater samples. This is the first speciation study of Tl carried out in suspended particulate matter. The results obtained indicate that the dominant form of Tl in suspended particulate matter is TlI, but TlIII could be found in suspended particulate matter fractions larger than 0.45µm.

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