ABSTRACT
The prediction of the thermodynamic properties of lactones is an important challenge in the flavor, fragrance, and pharmaceutical industries. Here, we develop a predictive model of the phase behavior of binary mixtures of lactones with hydrocarbons, alcohols, ketones, esters, aromatic compounds, water, and carbon dioxide. We extend the group-parameter matrix of the statistical associating fluid theory SAFT-γ Mie group-contribution method by defining a new cyclic ester group, denoted cCOO. The group is composed of two spherical Mie segments and two association electron-donating sites of type e1 that can interact with association electron-accepting sites of type H in other molecules. The model parameters of the new cCOO group interactions (1 like interaction and 17 unlike interactions) are characterized to represent target experimental data of physical properties of pure fluids (vapor pressure, single-phase density, and vaporization enthalpy) and mixtures (vapor-liquid equilibria, liquid-liquid equilibria, solid-liquid equilibria, density, and excess enthalpy). The robustness of the model is assessed by comparing theoretical predictions with experimental data, mainly for oxolan-2-one, 5-methyloxolan-2-one, and oxepan-2-one (also referred to as γ-butyrolactone, γ-valerolactone, and ε-caprolactone, respectively). The calculations are found to be in very good quantitative agreement with experiments. The proposed model allows for accurate predictions of the thermodynamic properties and highly nonideal phase behavior of the systems of interest, such as azeotrope compositions. It can be used to support the development of novel molecules and manufacturing processes.
ABSTRACT
Gougerot and Carteaud confluent and reticulated papillomatosis (CARP) is an uncommon dermatosis characterized by hyperpigmented scaly macules or papillomatous papules coalescing into confluent patches or plaques centrally with a reticular pattern peripherally. We report a 28-year-old woman presenting at 16 weeks of gestation with an itchy rash that was biopsied and turned out to be consistent with CARP. Options for treatment were discussed but the woman refused to take any systemic therapy and used only moisturizers throughout her pregnancy. The rash subsided spontaneously after delivery.
Subject(s)
Humans , Female , Pregnancy , Adult , Papilloma/pathology , Pregnancy Complications, Neoplastic/pathology , Skin Neoplasms/pathology , Remission, Spontaneous , Biopsy , Exanthema/pathologyABSTRACT
Gougerot and Carteaud confluent and reticulated papillomatosis (CARP) is an uncommon dermatosis characterized by hyperpigmented scaly macules or papillomatous papules coalescing into confluent patches or plaques centrally with a reticular pattern peripherally. We report a 28-year-old woman presenting at 16 weeks of gestation with an itchy rash that was biopsied and turned out to be consistent with CARP. Options for treatment were discussed but the woman refused to take any systemic therapy and used only moisturizers throughout her pregnancy. The rash subsided spontaneously after delivery.
