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This paper presents research on hydrodynamics and mass transfer in a packed absorption column. Experimental data on dry column pressure drop, flooding point, and efficiency of absorption of CO2 in water is obtained on a lab-scale absorption column packed with Raschig rings. Auxiliary parts of equipment together with chemical analyses provide simple monitoring and collecting the data. All obtained data were used to test different mathematical models for a given problem, i.e. for determination of the dry column pressure drop, flooding point and the overall gas transfer unit height. For dry column pressure drop, models developed primarily for packed columns described the data the best, with the Billet model generating a 6.54 % mean error, followed by Mackowiak and Stichlmair models. In flooding point calculations, empirical models were tested and models of Lobo, Leva and Takahshi gave the best results. Mass transfer (absorption) experiments gave expected results, since absorption efficiency increased with the increase in the liquid/gas flow rate ratio, i.e. with approaching the flooding point. The Onda’s model was used to calculate partial mass transfer coefficients in liquid and gas phases based on which the height of the overall gas transfer unit was estimated and subsequently compared with the experimental data. Deviation of calculated and experimental results for the height of the overall gas transfer unit is in the expected range of 0-20 %, with mean value of 15.5 %. In conclusion, the available models for determination of the investigated hydrodynamics and mass transfer parameters in packed absorption columns gave adequate results in comparison to the experimental values.

Background/Aim: The chemical nature of soft drinks is acidic, so they possess the capacity to cause hard tissue erosion. The aim of this study is to assess the potentially erosive effect linked to pH and titratable acidity of some common soft drinks on dental hard tissues in prolonged time exposure.

Obesity is a growing health burden worldwide, increasing the risk for several diseases featuring the metabolic syndrome – type 2 diabetes mellitus, dyslipidemia, non-alcoholic fatty liver disease and cardiovascular diseases. With the increasing epidemic of obesity, a new pathologic condition has emerged as a component of the metabolic syndrome – that of non-alcoholic fatty pancreas disease (NAFPD). Similar to non-alcoholic fatty liver disease (NAFLD), NAFPD comprises a wide spectrum of disease – from deposition of fat in the pancreas – fatty pancreas, to pancreatic inflammation and possibly pancreatic fibrosis. In contrast with NAFLD, diagnostic evaluation of NAFPD is less standardized, consisting mostly in imaging methods. Also the natural evolution of NAFPD and its association with pancreatic cancer is much less studied. Not least, the clinical consequences of NAFPD remain largely presumptions and knowledge about its metabolic impact is limited. This review will cover epidemiology, pathogenesis, diagnostic evaluation tools and treatment options for NAFPD, with focus on practices for clinicians.

Background. Celiac disease (CD) is significantly underdiagnosed, despite significant efforts made in the last decades to increase its diagnostic rate. This has lead to a high need for developing new diagnostic strategies. Our aim was to evaluate the diagnostic performance of two routine hematologic indices for CD. Methods. In a prospective observational study, 34 newly diagnosed CD patients, 34 age-sex matched controls with irritable bowel syndrome (IBS) and 16 treated CD patients were assessed regarding the differences in mean lymphocyte count (LY), red blood cell distribution width (RDW) and their ratio (RDW/LY). Results. Elevated RDW (>14) and lymphopenia (