scholarly journals A microfluidic methodology to identify the mechanical properties of capsules: comparison with a microrheometric approach

Flow ◽  
2021 ◽  
Vol 1 ◽  
Author(s):  
Xing-Yi Wang ◽  
Adlan Merlo ◽  
Claire Dupont ◽  
Anne-Virginie Salsac ◽  
Dominique Barthès-Biesel
Keyword(s):  
Elastic Properties ◽  
Capillary Tube ◽  
Ease Of Use ◽  
Constitutive Law ◽  
Small Samples ◽  
Wall Material ◽  
Capsule Wall ◽  
Elastic Parameters ◽  
Liquid Drops ◽  
Spherical Capsule

We present a microfluidic method to measure the elastic properties of a population of microcapsules (liquid drops enclosed by a thin hyperelastic membrane). The method is based on the observation of flowing capsules in a cylindrical capillary tube and an automatic inverse analysis of the deformed profiles. The latter requires results from a full numerical model of the fluid–structure interaction accounting for nonlinear membrane elastic properties. For ease of use, we provide them under the form of databases, when the initially spherical capsule has a membrane governed by a neo-Hookean or a general Hooke's law with different surface Poisson ratios. Ultimately, the microfluidic method yields information on the type of elastic constitutive law that governs the capsule wall material together with the value of the elastic parameters. The method is applied to a population of ovalbumin microcapsules and is validated by means of independent experiments of the same capsules subjected to a different flow in a microrheological device. This is of great interest for quality control purposes, as small samples of capsule suspensions can be diverted to a measuring test section and mechanically tested with a 10 % precision using an automated process.

Microencapsulated Antidegradants for Extending Rubber Lifetime

1992 ◽  
Vol 65 (1) ◽  
pp. 201-210 ◽  
Author(s):  
Larry R. Evans ◽  
David A. Benko ◽  
James G. Gillick ◽  
Walter H. Waddell
Keyword(s):  
Cellulose Acetate ◽  
Migration Rate ◽  
Wall Material ◽  
Drying Process ◽  
Capsule Wall ◽  
Rubber Compounds ◽  
Process Studies ◽  
Lifetime Testing ◽  
Processing Properties ◽  
Rubber Article

Abstract Microcapsules containing rubber antidegradants were formed in a spray-drying process. Studies were carried out to select the proper wall material based on the processing properties, migration rate of the antidegradant through the capsule wall, thickness of the capsule wall, and overall capsule diameter. The resulting capsules were incorporated into a rubber article, providing a reservoir of antidegradant during the exposure lifetime. Testing of the rubber compounds with microcapsules having diameters less than 50 µm containing AN-(l,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine in a matrix of cellulose acetate showed a significant increase in the crack-free lifetime of the rubber when flexed in exposure to ozone.

Modeling of elastic properties of cell-wall material in nanoclay-reinforced foams

2015 ◽  
Vol 52 (1) ◽  
pp. 107-130 ◽  
Author(s):  
Oksana Shishkina ◽  
Stepan V Lomov ◽  
Ignaas Verpoest ◽  
Larissa Gorbatikh
Keyword(s):  
Cell Wall ◽  
Elastic Properties ◽  
Wall Material ◽  
Cell Wall Material

Seismic inversion for reservoir properties combining statistical rock physics and geostatistics: A review

Geophysics ◽  
2010 ◽  
Vol 75 (5) ◽  
pp. 75A165-75A176 ◽  
Author(s):  
Miguel Bosch ◽  
Tapan Mukerji ◽  
Ezequiel F. Gonzalez
Keyword(s):  
Elastic Properties ◽  
Quantitative Estimation ◽  
Rock Physics ◽  
Seismic Inversion ◽  
Elastic Parameters ◽  
Reservoir Properties ◽  
Sequential Approach ◽  
Geostatistical Methods ◽  
Bayesian Formulation ◽  
Statistical Rock Physics

There are various approaches for quantitative estimation of reservoir properties from seismic inversion. A general Bayesian formulation for the inverse problem can be implemented in two different work flows. In the sequential approach, first seismic data are inverted, deterministically or stochastically, into elastic properties; then rock-physics models transform those elastic properties to the reservoir property of interest. The joint or simultaneous work flow accounts for the elastic parameters and the reservoir properties, often in a Bayesian formulation, guaranteeing consistency between the elastic and reservoir properties. Rock physics plays the important role of linking elastic parameters such as impedances and velocities to reservoir properties of interest such as lithologies, porosity, and pore fluids. Geostatistical methods help add constraints of spatial correlation, conditioning to different kinds of data and incorporating subseismic scales of heterogeneities.

Prediction of Equilibrium and Stability of Molten Solder Geometries by Finite Element Analysis

2005 ◽  
Author(s):  
Takahiro Nagata ◽  
Takaya Kobayashi
Keyword(s):  
Surface Tension ◽  
Liquid Drop ◽  
Dynamic Effect ◽  
Shell Element ◽  
Molten Solder ◽  
Constitutive Laws ◽  
Constitutive Law ◽  
Creep Model ◽  
Element Analysis ◽  
Liquid Drops

Improving the reliability on solder joints is one of the major tasks to achieve downsizing of electronics products. Taking the molten solder profile as an object of study, a new procedure to model solder liquid with a structural FEM has been developed, which enables us to solve an issue of predefining the geometrical profile of solder liquid drops in a state of static equilibrium taking the surface tension into account, and also a problem concerning dynamic stability of the liquid drops. Molten solder liquid is treated as viscous fluid. Deformation of the material due to its viscosity can be represented by the structural analysis using rheological approach. Two types of the constitutive laws, creep model or viscoelasticity model, can be applied. Such a simple case as the Newtonian fluid, either constitutive law may be employed. Using these types of the constitutive laws in the analysis with time incremental steps, it becomes possible not only to obtain the stabilized shape of liquid drops, but also to analyze problems involved with transient (including dynamic effect) stability. As the size of a liquid drop is microscopic in a range of 100 to 1000 μm, the effect of the surface tension must become so predominant in the loading conditions. In most of the conventional theoretical researches, it is found that the surface tension is treated as the pressure difference varying according to the surface curvature. However, this method is not only so complicated, but also may lead to numerical instability particularly in the transient analysis subjected to large deformations. In this study, an effective method has been developed in which the surface tension can be represented with good accuracy through simplified input data with allocating the shell element generating a constant membrane force over the surface of a liquid drop.

scholarly journals Microencapsulation: concepts, mechanisms, methods and some applications in food technology

2014 ◽  
Vol 44 (7) ◽  
pp. 1304-1311 ◽  
Author(s):  
Pablo Teixeira da Silva ◽  
Leadir Lucy Martins Fries ◽  
Cristiano Ragagnin de Menezes ◽  
Augusto Tasch Holkem ◽  
Carla Luisa Schwan ◽  
...  
Keyword(s):  
New Technology ◽  
Correct Choice ◽  
Wall Material ◽  
Food Technology ◽  
Capsule Wall ◽  
Food Industries ◽  
Encapsulation Method ◽  
Encapsulation Methods ◽  
Release Form ◽  
Active Substances

Microencapsulation is a process in which active substances are coated by extremely small capsules. It is a new technology that has been used in the cosmetics industry as well as in the pharmaceutical, agrochemical and food industries, being used in flavors, acids, oils, vitamins, microorganisms, among others. The success of this technology is due to the correct choice of the wall material, the core release form and the encapsulation method. Therefore, in this review, some relevant microencapsulation aspects, such as the capsule, wall material, core release forms, encapsulation methods and their use in food technology will be briefly discussed.

Elastic Properties of Solid Solutions with Intermediate Valence Sm1-xYxS

2015 ◽  
Vol 770 ◽  
pp. 137-143
Author(s):  
E.G. Soboleva ◽  
A.L. Igisheva ◽  
T.B. Krit
Keyword(s):  
Elasticity Theory ◽  
Elastic Properties ◽  
Solid Solutions ◽  
Elastic Moduli ◽  
Intermediate Valence ◽  
Elastic Parameters ◽  
Valence Transition ◽  
The Given ◽  
Poisson's Ratios ◽  
Poisson’S Ratios

The given article considers acoustic analogues of elasticity theory ratios determining Poisson’s ratios of Sm1-xYxS alloy by their elastic parameters. The article discusses behavior of sound velocities, elastic moduli, Poisson’s ratios, Grüneisen parameter and brittleness-plasticity criterion ratios depending on the concentration of alloy components including valence transition from semiconductors into the metal phase.

Geomechanical properties of carbonate reservoir rocks and middle carbon cap rocks of the Ivinskoe oilfield

2021 ◽  
pp. 104-109
Author(s):  
V. Е. Kosarev ◽  
◽  
E. R. Ziganshin ◽  
I. P. Novikov ◽  
A. N. Dautov ◽  
...  
Keyword(s):  
Elastic Properties ◽  
Carbonate Reservoir ◽  
Textural Features ◽  
Laboratory Studies ◽  
Elastic Parameters ◽  
Geomechanical Model ◽  
Geomechanical Properties ◽  
Reservoir Rocks ◽  
Rock Laboratory ◽  
Middle Carboniferous

Laboratory studies of the geomechanical properties of rocks are an important and integral part in building a geomechanical model. This study resulted in a set of data on geomechanical and elastic properties of the rocks that compose the lower part of the Middle Carboniferous section of the Ivinskoye oilfield (Russia). Relationships between various elastic parameters were also established. The distribution of geomechanical properties correlates with structural/textural features of the rocks under study and their lithological type. This information can be used as a basis for geomechanical modeling and in preparation for hydraulic fracturing. Keywords: geomechanics; elastic properties; carbonate rock; laboratory core studies.

scholarly journals Likely equilibria of the stochastic Rivlin cube

2019 ◽  
Vol 377 (2144) ◽  
pp. 20180068 ◽  
Author(s):  
L. Angela Mihai ◽  
Thomas E. Woolley ◽  
Alain Goriely
Keyword(s):  
Applied Mathematics ◽  
Experimental Tests ◽  
Constitutive Law ◽  
Elastic Parameters ◽  
Theme Issue ◽  
Stochastic Version ◽  
The Stability ◽  
Material Constitutive Law ◽  
Standard Probability ◽  
Data Variation

The problem of the Rivlin cube is to determine the stability of all homogeneous equilibria of an isotropic incompressible hyperelastic body under equitriaxial dead loads. Here, we consider the stochastic version of this problem where the elastic parameters are random variables following standard probability laws. Uncertainties in these parameters may arise, for example, from inherent data variation between different batches of homogeneous samples, or from different experimental tests. As for the deterministic elastic problem, we consider the following questions: what are the likely equilibria and how does their stability depend on the material constitutive law? In addition, for the stochastic model, the problem is to derive the probability distribution of deformations, given the variability of the parameters. This article is part of the theme issue ‘Rivlin's legacy in continuum mechanics and applied mathematics’.

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