Quasi-Linear Viscoelastic Characterization of Soft Tissue-Mimicking Materials

Abstract We present a novel method based on the quasi-linear viscoelastic (QLV) theory to describe the time-dependent behavior of soft materials. Unlike previous methods for deriving QLV parameters, we characterize the elastic and viscous behavior of materials separately by using two different sets of experiments. To model the nonlinear elastic behavior, we fit the elastic stress response with a one-term Ogden model. Then, we model the relaxation behavior with a Prony series to compare the stress relaxation of the material at different timescales. This new method allows us to characterize materials with narrow confidence intervals (high accuracy), independently from the loading conditions. We validate our model using samples made of phantom materials that mimic normal and cancerous prostate tissues in terms of Young's modulus. Our model is shown to distinguish materials with similar elastic (viscous) properties but different viscous (elastic) properties. Drawing a precise distinction between the phantoms, this method could be useful for prostate cancer (PCa) diagnosis; but significant clinical studies will be needed in the future.

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Characterization of the Nonlinear Elastic Behavior of Chinchilla Tympanic Membrane Using Micro-fringe Projection

Conference Proceedings of the Society for Experimental Mechanics Series - Mechanics of Composite and Multi-functional Materials, Volume 7 ◽

10.1007/978-3-319-21762-8_26 ◽

2016 ◽

pp. 219-224

Author(s):

Junfeng Liang ◽

Huiyang Luo ◽

Don Nakmali ◽

Rong Zhu Gan ◽

Hongbing Lu

Keyword(s):

Tympanic Membrane ◽

Fringe Projection ◽

Elastic Behavior ◽

Nonlinear Elastic

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Characterization of the nonlinear elastic behavior of chinchilla tympanic membrane using micro-fringe projection

Hearing Research ◽

10.1016/j.heares.2016.05.012 ◽

2016 ◽

Vol 339 ◽

pp. 1-11 ◽

Cited By ~ 13

Author(s):

Junfeng Liang ◽

Huiyang Luo ◽

Zachary Yokell ◽

Don U. Nakmali ◽

Rong Zhu Gan ◽

...

Keyword(s):

Tympanic Membrane ◽

Fringe Projection ◽

Elastic Behavior ◽

Nonlinear Elastic

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Thermoelastic characterization of carbon nanotube reinforced PDMS elastomer

Journal of Polymer Engineering ◽

10.1515/polyeng-2020-0118 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Jinu Paul

Keyword(s):

Carbon Nanotube ◽

Internal Energy ◽

Elastic Stress ◽

Entropy Change ◽

Elastic Behavior ◽

Entropy Contribution ◽

Pdms Elastomer ◽

Directional Preference ◽

Low Entropy

AbstractInternal energy and entropy contribution to the elasticity of carbon nanotube reinforced polydimethylsiloxane (PDMS) is evaluated using statistical theory of rubber elasticity. Stress–temperature measurements were performed and the data was used to calculate the internal energy contribution to elastic stress. Interesting aspects such as increase in energy and low entropy contribution to the elasticity of carbon nanotube reinforced PDMS is observed. This can be related t o the deformation behavior of the network chains of pristine elastomers and the directional reorientation of nanotube entanglements. While the entropy change is associated with reorientation or directional preference of the carbon nanotube entanglements, the internal energy change is associated with structural bending or stretching of the nanotubes. A reversible deformation of nanotube entanglements complements rubber like elasticity and the present study gives insights into the thermoelasticity of reinforced elastomers as well as the elastic behavior of carbon nanotube entanglements inside a polymer matrix.

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Adsorption Studies on Magnetic Nanoparticles Functionalized with Silver to Remove Nitrates from Waters

Water ◽

10.3390/w13131757 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1757

Author(s):

Yesica Vicente-Martínez ◽

Manuel Caravaca ◽

Antonio Soto-Meca ◽

Miguel Ángel Martín-Pereira ◽

María del Carmen García-Onsurbe

Keyword(s):

Magnetic Nanoparticles ◽

Nitrate Content ◽

Adsorption Efficiency ◽

Experimental Conditions ◽

Dependent Behavior ◽

Before And After ◽

Naoh Solution ◽

High Concentrations ◽

Interference Studies

This paper presents a novel procedure for the treatment of contaminated water with high concentrations of nitrates, which are considered as one of the main causes of the eutrophication phenomena. For this purpose, magnetic nanoparticles functionalized with silver (Fe3O4@AgNPs) were synthesized and used as an adsorbent of nitrates. Experimental conditions, including the pH, adsorbent and adsorbate dose, temperature and contact time, were analyzed to obtain the highest adsorption efficiency for different concentration of nitrates in water. A maximum removal efficiency of 100% was reached for 2, 5, 10 and 50 mg/L of nitrate at pH = 5, room temperature, and 50, 100, 250 and 500 µL of Fe3O4@AgNPs, respectively. The characterization of the adsorbent, before and after adsorption, was performed by energy dispersive X-ray spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. Nitrates can be desorbed, and the adsorbent can be reused using 500 µL of NaOH solution 0.01 M, remaining unchanged for the first three cycles, and exhibiting 90% adsorption efficiency after three regenerations. A deep study on equilibrium isotherms reveals a pH-dependent behavior, characterized by Langmuir and Freundlich models at pH = 5 and pH = 1, respectively. Thermodynamic studies were consistent with physicochemical adsorption for all experiments but showed a change from endothermic to exothermic behavior as the temperature increases. Interference studies of other ions commonly present in water were carried out, enabling this procedure as very selective for nitrate ions. In addition, the method was applied to real samples of seawater, showing its ability to eliminate the total nitrate content in eutrophized waters.

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A novel method for the quantitative characterization of the simultaneous plasticizing and filling performance in ultrasonic plasticization micro injection molding

Materials & Design ◽

10.1016/j.matdes.2021.109680 ◽

2021 ◽

pp. 109680

Author(s):

Yang Zou ◽

Wangqing Wu ◽

Xiaotian Zhou ◽

Guomeng Wei ◽

Bingyan Jiang

Keyword(s):

Injection Molding ◽

Quantitative Characterization ◽

Micro Injection Molding ◽

Novel Method

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Material parametrization of natural rubber based compound and characterization of crack propagation under consideration of dissipative effects

Journal of Rubber Research ◽

10.1007/s42464-021-00094-8 ◽

2021 ◽

Author(s):

Dan Pornhagen ◽

Konrad Schneider ◽

Markus Stommel

Keyword(s):

Energy Dissipation ◽

Crack Propagation ◽

Natural Rubber ◽

Experimental Tests ◽

Material Behavior ◽

Prony Series ◽

Material Forces ◽

Cracking Behavior ◽

Dissipative Effects

AbstractMost concepts to characterize crack propagation were developed for elastic materials. When applying these methods to elastomers, the question is how the inherent energy dissipation of the material affects the cracking behavior. This contribution presents a numerical analysis of crack growth in natural rubber taking energy dissipation due to the visco-elastic material behavior into account. For this purpose, experimental tests were first carried out under different load conditions to parameterize a Prony series as well as a Bergström–Boyce model with the results. The parameterized Prony series was then used to perform numerical investigations with respect to the cracking behavior. Using the FE-software system ANSYS and the concept of material forces, the influence and proportion of the dissipative components were discussed.

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Visco-Hyperelastic Characterization of the Equine Immature Zona Pellucida

Materials ◽

10.3390/ma14051223 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1223

Author(s):

Elisa Ficarella ◽

Mohammad Minooei ◽

Lorenzo Santoro ◽

Elisabetta Toma ◽

Bartolomeo Trentadue ◽

...

Keyword(s):

Zona Pellucida ◽

Soft Matter ◽

Mechanical Response ◽

Mechanical Characterization ◽

Nonlinear Material ◽

Prony Series ◽

Critical Comparison ◽

Highly Nonlinear ◽

Good Agreement

This article presents a very detailed study on the mechanical characterization of a highly nonlinear material, the immature equine zona pellucida (ZP) membrane. The ZP is modeled as a visco-hyperelastic soft matter. The Arruda–Boyce constitutive equation and the two-term Prony series are identified as the most suitable models for describing the hyperelastic and viscous components, respectively, of the ZP’s mechanical response. Material properties are identified via inverse analysis based on nonlinear optimization which fits nanoindentation curves recorded at different rates. The suitability of the proposed approach is fully demonstrated by the very good agreement between AFM data and numerically reconstructed force–indentation curves. A critical comparison of mechanical behavior of two immature ZP membranes (i.e., equine and porcine ZPs) is also carried out considering the information on the structure of these materials available from electron microscopy investigations documented in the literature.

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Creation of Ionically Crosslinked Tri-Layered Chitosan Membranes to Simulate Different Human Skin Properties

Materials ◽

10.3390/ma14071807 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1807

Author(s):

Rocío Guerle-Cavero ◽

Blanca Lleal-Fontàs ◽

Albert Balfagón-Costa

Keyword(s):

Elastic Modulus ◽

Human Skin ◽

Sodium Tripolyphosphate ◽

Snow Crab ◽

Suitable Material ◽

Cosmetic Industry ◽

Novel Method ◽

Current Article ◽

Chitosan Membranes

In 2023, new legislation will ban the use of animals in the cosmetic industry worldwide. This fact, together with ethical considerations concerning the use of animals or humans in scientific research, highlights the need to propose new alternatives for replacing their use. The aim of this study is to create a tri-layered chitosan membrane ionically crosslinked with sodium tripolyphosphate (TPP) in order to simulate the number of layers in human skin. The current article highlights the creation of a membrane where pores were induced by a novel method. Swelling index, pore creation, and mechanical property measurements revealed that the swelling index of chitosan membranes decreased and, their pore formation and elasticity increased with an increase in the Deacetylation Grade (DDA). Additionally, the results demonstrate that chitosan’s origin can influence the elastic modulus value and reproducibility, with higher values being obtained with seashell than snow crab or shrimp shells. Furthermore, the data show that the addition of each layer, until reaching three layers, increases the elastic modulus. Moreover, if layers are crosslinked, the elastic modulus increases to a much greater extent. The characterization of three kinds of chitosan membranes was performed to find the most suitable material for studying different human skin properties.

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