caa a22 4500 469050381 CHVBK 20180323132829.0 cr unu---uuuuu 170328e19920301xx s 000 0 eng 10.1007/BF02493417 doi (NATIONALLICENCE)springer-10.1007/BF02493417 Viscosity measurements of barium sulfate mixtures for use in motility studies of the pharynx and esophagus [Elektronische Daten] [Meijing Li, James Brasseur, Mark Kern, Wylie Dodds] Detailed viscosity measurements have been made of barium sulfate mixtures over a wide range of viscosities for use in radiography of the esophagus, stomach, and duodenum. A new methodology was developed for more accurate estimation of viscosity in non-Newtonian fluids in conventional cylinder-type viscometers. As base cases, the variation of viscosity with shear rate was measured for standard commercial mixes of e·z·hd (250% w/v) and a diluted mixture of liquid e·z·paque (40% w/v). These suspensions are strongly shear thinning at low shear rates. Above about 3s−1 the viscosity is nearly constant, but relatively low. To increase the viscosity of the barium sulfate mixture, Knott's strawberry syrup was mixed to different proportions with e·z·hd powder. In this way viscosity was systematically increased to values 130,000 times that of water. For these mixtures the variation of viscosity with temperature, and the change in mixture density with powder-syrup ratio are documented. From least-square fits through the data, simple mathematical formulas are derived for approximate calculation of viscosity as a function of mixture ratio and temperature. These empirical formulas should be useful in the design of "test kits” for systematic study for pharyngeal and esophageal motility, and clinical analysis of motility disorders as they relate to bolus consistency. Springer-Verlag New York Inc, 1992 Viscosity nationallicence Bolus viscosity nationallicence Rheology nationallicence Shear rate nationallicence Viscometer nationallicence Viscometry nationallicence Deglutition nationallicence Deglutition disorders nationallicence Li Meijing Department of Mechanical Engineering, Pennsylvania State University, 208 Mechanical Engineering Building, 16802, University Park, Pennsylvania, USA aut Brasseur James Department of Mechanical Engineering, Pennsylvania State University, 208 Mechanical Engineering Building, 16802, University Park, Pennsylvania, USA aut Kern Mark Departments of Medicine, Radiology, and Surgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA aut Dodds Wylie Departments of Medicine, Radiology, and Surgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA aut Dysphagia Springer-Verlag 7/1(1992-03-01), 17-30 0179-051X 7:1<17 1992 7 455 https://doi.org/10.1007/BF02493417 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02493417 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Li Meijing Department of Mechanical Engineering, Pennsylvania State University, 208 Mechanical Engineering Building, 16802, University Park, Pennsylvania, USA aut NATIONALLICENCE 700 1- Brasseur James Department of Mechanical Engineering, Pennsylvania State University, 208 Mechanical Engineering Building, 16802, University Park, Pennsylvania, USA aut NATIONALLICENCE 700 1- Kern Mark Departments of Medicine, Radiology, and Surgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA aut NATIONALLICENCE 700 1- Dodds Wylie Departments of Medicine, Radiology, and Surgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA aut NATIONALLICENCE 773 0- Dysphagia Springer-Verlag 7/1(1992-03-01), 17-30 0179-051X 7:1<17 1992 7 455 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer