The influences of several operating factors on the viscosity of the Isfahan refinery waxy crude oil sample are studied through conducting some rheological shear rotational tests. The Taguchi design method is adopted to determine the impact of factors such as shear rate, temperature, cooling rate, wax content, and asphaltene content on the viscosity of the waxy crude oil. The results show that t...

We report theoretical and numerical results on thermal convection of a magnetic fluid in a viscoelastic carrier liquid. The viscoelastic properties are described by a general nonlinear viscoelastic model that contains as special cases the standard phenomenological constitutive equations for the stress tensor. In order to explore numerically the system we perform a truncated Galerkin expansion o...

Cell adhesive and rheological properties play a very important role in cell transmigration through the endothelial barrier, in particular in the case of inflammation (leukocytes) or cancer metastasis (cancer cells). In order to characterize cell viscoelastic properties, we have designed a force spectrometer (AFM) which can stretch cells thereby allowing measurement of their rheological properti...

The mechanical testing of thin layers of soft materials is an important but difficult task. Spherical indentation provides a convenient method to ascertain material properties whilst minimising damage to the material by allowing testing to take place in situ. However, measurement of the viscoelastic properties of these soft materials is hindered by the absence of a convenient yet accurate model...

fruit yoghurt is frequently made with fermented milk products; however, the use of fruit and its products may cause changes in the viscoelastic properties, syneresis and sensory properties of fruit yoghurt. one approach to improve these properties in fruit yoghurt is the use of thickening agents. this study investigated the effect of carboxymethyl cellulose and guar thickening agents on the pro...

OBJECTIVE To characterize the viscoelastic properties of cervical mucus plugs(CMPs) shed during labor at term. DESIGN Experimental research. SETTING Department of Obstetrics and Gynecology, Aarhus University Hospital, Denmark. POPULATION/SAMPLE Spontaneously shed CMPs from 18 healthy women in active labor. METHODS Viscoelastic properties of CMPs were investigated with a dynamic oscillat...

Ultrasound Contrast Agents (UCAs) composed ofgaseous microbubbles exhibit acoustic properties that differ fromthose surrounding tissue. In order to increase the contrast totissue ratio, it is necessary to propose methods that characterizeoptimally the ultrasonic properties of UCAs. The aim of thisstudy is to measure the viscoelastic properties of UCAs using adynamic acou...

Cartilage material properties provide important insights into joint health, and cartilage material models are used in whole-joint finite element models. Although the biphasic model representing experimental creep indentation tests is commonly used to characterize cartilage, cartilage short-term response to loading is generally not characterized using the biphasic model. The purpose of this stud...

The viscoelastic properties of new experimental tissue conditioners which consist of synthesized poly (butyl methacrylate) PBMA and a liquid of aromatic-ester plasticizer, without alcohol, were investigated to evaluate the effects of the molecular weight of polymer. The master curves of storage modulus G', dynamic viscosity eta' and loss tangent tan delta were constructed from the viscoelastic ...

We used a novel atomic force microscopy (AFM)-based technique to compare the local viscoelastic properties of individual gram-negative (Escherichia coli) and gram-positive (Bacillus subtilis) bacterial cells. We found that the viscoelastic properties of the bacterial cells are well described by a three-component mechanical model that combines an instantaneous elastic response and a delayed elas...