The solubility of paracetamol in water-isopropanol mixtures at 30 °C using the regular-solution theory, the UNIFAC model, and the UNIQUAC model is predicted and compared with the corresponding experimental values reported in part A of this study. The results of the ideal solubility show that ∆c p should be integrated with respect to differential molar heat capacity changes with temperature, if sub-cooled liquid heat capacity is approximated by liquid heat capacity. The modified regularsolution theory underestimates the solubility, whereas the UNIFAC model overestimates it. The UNIQUAC model results in the best predictions. However, various vapor-liquid equilibrium data sets to calculate the UNIQUAC solvent-solvent adjustable parameters result in different accuracies.

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A fuzzy logic control approach is developed for the control of a seeded semibatch crystallizer. Crystallization of paracetamol (PA) in 2-propanol-water mixtures was used as the model system. The concentration and cord length counts were measured using an in situ attenuated total reflection Fourier transform infrared probe and an in situ focused beam reflectance measurement probe, respectively. Three open-loop feeding policies, concave (CCFP, similar to natural cooling), linear (LFP), and convex (CVFP, near controlled cooling), were employed to investigate the process dynamic behavior to construct the fuzzy controller structure for the control of supersaturation within a predefined zone close to the solubility curve. It is found that the fuzzy controller can ensure tracking of the concentration within the zone, leading to substantial improvement of the end product size distribution compared to the open-loop results. Selecting the initial PA concentration above the upper limit of the concentration results in longer process times. The open-loop results show that the feeding policy (addition of water) does not prevent nucleation and agglomeration; however, both phenomena can be minimized by the LFP.

The kinetic parameters of ferrous iron oxidation, covering both lag and growth phases at low pH, were determined using a free suspended culture of the bacterium Leptospirillum ferriphilum. A mathematical model was developed to simulate the dynamics of a continuous bioreactor used for operation of a novel hybrid Fe(II)/Fe(III) redox flow fuel cell system. By changing the current load within a predefined range, three runs were performed to predict time-varying ferrous iron concentration, bacterial cell concentration, and pH as the major output variables of simulation program. The model was experimentally validated through three runs. It was found out that the key variable in dynamic analysis of the bioreactor was the current load applied. To optimize the bioreactor and the fuel cell conditions for a normalsteady-state operation, the optimal current profile for a transient phase was determined. A selected optimal policy was also implemented and validated during the mini-pilot-scale system experiments.

In the neck or face, there are different causes for subcutaneous emphysema such as injury to the sinuses, the hypopharynx, the laryngotracheal complex, the pulmonary parenchyma, the esophagus or the presence of gas-forming organisms. However, factitious subcutaneous emphysema, a rare cause, must be considered in the differential diagnosis. In this clinical report, we discuss a 20-year-old girl who was under follow-up because of recurrent subcutaneous emphysema of the face and periorbital area. After 2 years of work-ups, including a period of close observation in the intensive care unit, self air injection by syringe was found as the cause of recurrent subcutaneous emphysema of the face, and the patient was labeled as having factitious recurrent subcutaneous emphysema. Therefore, when a patient presents with unexplained recurrent subcutaneous emphysema, one should suspect self-infliction and examine for puncture marks.